naphthoquinones and Disease-Models--Animal

Napabucasin (BBI608) is an orally administered small molecule that blocks stem cell activity in cancer cells by targeting the signal transducer and activator of transcription 3 pathway. The signal transducer and activator of transcription 3 pathway is over-activated in many types of cancer and has been shown to be an important pathway in cancer stem cell-mediated propagation of cancer. Cancer stem cells are a subpopulation of cancer cells considered to be the primary source of tumor growth, metastasis, and resistance to conventional therapies, and thus, responsible for cancer relapse. This review describes the clinical development program of this first-in-class cancer stemness inhibitor, including preclinical discovery, early clinical trials, current phase III clinical trial evaluation, and future therapeutic combinations. The therapeutic potential of napabucasin was first reported in a preclinical study that demonstrated the potent anti-tumor and anti-metastatic activity of napabucasin in several different cancer types, both in vitro and in vivo. In mouse models, napabucasin was effective both as a monotherapy and in combination with other agents; in particular, synergy was observed with paclitaxel in vivo. Napabucasin clinical trials have demonstrated encouraging anti-tumor activity as monotherapy and in combination with conventional therapeutics, with no significant pharmacokinetic interactions when used in combination therapies. Adverse events attributed to napabucasin have been predominantly mild, although some patients have experienced grade 3 gastrointestinal adverse events. More severe adverse events required reduced or discontinued dosing of napabucasin or medication to reverse or manage symptoms. In conclusion, napabucasin may prove useful in targeting cancer stem cells, with the potential to suppress metastasis and prevent relapse in patients with varying cancer types.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Benzofurans; Clinical Trials as Topic; Disease Models, Animal; Humans; Naphthoquinones; Neoplasms; Neoplastic Stem Cells; STAT3 Transcription Factor

Poly (ADP-ribose) polymerases (PARPs) are a family of related enzymes that share the ability to catalyze the transfer of ADP-ribose to target proteins. PARPs play an important role in various cellular processes, including modulation of chromatin structure, transcription, replication, recombination, and DNA repair. The role of PARP proteins in DNA repair is of particular interest, in view of the finding that certain tumors defective in homologous recombination mechanisms, may rely on PARP-mediated DNA repair for survival, and are sensitive to its inhibition. PARP inhibitors may also increase tumor sensitivity to DNA-damaging agents. Clinical trials of PARP inhibitors are investigating the utility of these approaches in cancer. The hyperactivation of PARP has also been shown to result in a specific programmed cell death pathway involving NAD+/ATP depletion, mu-calpain activation, loss of mitochondrial membrane potential, and the release of apoptosis inducing factor. Hyperactivation of the PARP pathway may be exploited to selectively kill cancer cells. Other PARP forms, including tankyrase 1 (PARP 5a), which plays an important role in enhancing telomere elongation by telomerase, have been found to be potential targets in cancer therapy. The PARP pathway and its inhibition thus offers a number of opportunities for therapeutic intervention in both cancer and other disease states.

Topics: Animals; Disease Models, Animal; DNA Repair; Enzyme Inhibitors; Epigenesis, Genetic; Humans; Molecular Targeted Therapy; Nanomedicine; Naphthoquinones; Necrosis; Neoplasms; Poly(ADP-ribose) Polymerase Inhibitors; Poly(ADP-ribose) Polymerases; Transcription Factors

Human infections with Babesia species, in particular Babesia microti, are tick-borne illnesses that are being recognised with increased frequency. Coinfection with ehrlichiosis and Lyme disease is also being recognised as an important feature of these tick-borne illnesses. Despite the superficial resemblance of Babesia to malaria, these piroplasms do not respond to chloroquine or other similar drugs. However, the treatment of babesiosis using a clindamycin-quinine combination has been successful. Data in animal models and case-reports in humans have suggested that an atovaquone-azithromycin combination is also effective. This was confirmed in a recent prospective, open, randomised trial of clindamycin-quinine versus azithromycin-atovaquone. This paper reviews the literature on the treatment of human babesiosis and the animal models of these human pathogens.

Topics: Animals; Anti-Bacterial Agents; Atovaquone; Azithromycin; Babesia microti; Babesiosis; Clindamycin; Disease Models, Animal; Drug Administration Schedule; Drug Therapy, Combination; Humans; Naphthoquinones; Randomized Controlled Trials as Topic

Dihydroxyacetone (DHA) chemically induces long ultraviolet (UV) and/or visible photoprotection into the stratum corneum as demonstrated by (a) long UV protection of albino rats which were psoralen-photosensitized to black fluorescent light and (b) sunlight protection of five patients with long UV and/or visible photosensitivity. Previously, DHA treatment of skin was considered to provide no protection against UV. For clinical use, the combination of DHA and lawsone (2-hydroxy-1,4-naphthoquinone) is preferred to DHA alone, because it provides rapid, positive protection over a range extending from short UV into the visible region of sunlight.

Topics: Administration, Topical; Adolescent; Adult; Animals; Child; Dihydroxyacetone; Disease Models, Animal; Drug Combinations; Female; Humans; Light; Male; Middle Aged; Naphthoquinones; Photosensitivity Disorders; Rats; Sunscreening Agents; Trioses; Ultraviolet Rays

β-lapachone (β-lap) is a naphthoquinone widely found in species of vegetables. However, its poor aqueous solubility limits its systemic administration and clinical applications in vivo. To overcome this limitation, several studies have been carried out in order to investigate techniques that can enhance the solubility and dissolution rate of β-lap, such as the use of inclusion complexes with cyclodextrin.. To evaluate the in vivo effect of β-lap complexed in methyl-β-cyclodextrin (MβCD) on the evolutionary stages of Schistosoma mansoni in a murine model.. The development and characterization of the physicochemical properties of the inclusion complex of β-lap in β-lap:MβCD was prepared by solubility and dissolution tests, FTIR, DSC, X-RD and SEM. The mice were infected and subsequently treated with β-lap:MβCD orally with 50 mg/kg/day and 100 mg/kg/day for 5 consecutive days, starting therapy on the 1. The loss of the crystalline form of β-lap in the β-lap:MβCD complex obtained by spray drying was proven through physical-chemical characterization analyses. β-lap:MβCD caused reduction in the number of worms of the 33.56%, 35.7%, 35.45% and 36.45%, when the dose was at 50 mg/kg, and 65.00%, 60.34%, 52.72% and 65.01%, in the dose 100 mg/kg; when treatment was started in the 1. The dissolved content of β-lap:MβCD by spray drying reached almost 100%, serving for future formulations and delineation of the mechanisms of action of β-lap against S. mansoni.

Topics: Animals; Disease Models, Animal; Mice; Naphthoquinones; Schistosoma mansoni; Spray Drying

Allergic rhinitis (AR) is a disease in the nasal mucosa related with Th2 lymphocyte inflammatory action. Dendritic cells (DCs) have been proved that they played a significant role in the development and maintenance of AR. However, there is still a lack of specific therapies for DCs in clinical practice. Shikonin (SHI) is a natural naphthoquinone compound isolated from the Chinese herb Radix Arnebiae. It is reported that SHI can interference the phenotype and function of dendritic cells, so we speculate that SHI may be an effective drug for the treatment of AR. However, the clinical usage of SHI has been limited by the bioactive properties of poor solubility, short retention time and low bioavailability. Therefore, in order to better exert the anti-inflammatory effect of SHI, an efficient SHI delivery system is urgently needed.. We prepared and characterized SHI-PM and NGR-SHI-PM with the thin-film hydration method. We used retrodialysis method to explore the release behavior. We took immunofluorescence to investigate the expression of CD13 in vitro. Then we tested BM-DCs mature cell detection by flow cytometry. An allergic rhinosinusitis murine model, hematoxylin and eosin stain and flow cytometry were established to test the efficiency of anti-inflammation in vivo. At last, western blot analysis and plasmid construction and transfection assay were taken to reveal the molecular mechanisms.. In the present study, we revealed that NGR-modifified could strengthen the intracellular uptake of PM (p < 0.001) and CD13 was high expressed on mature BM-DCs (p < 0.001). NGR-modified could enhance the inhibition of SHI in vitro (p < 0.05). NGR-modifified could increase the distribution of PM in vivo by DiI fluorescently (p < 0.01). NGR-modified could enhance SHI anti-allergic activity in OVA-sensitized mice and enhance the inhibition of SHI on DC maturation in lymph node (p < 0.001). Our findings also suggest that SHI may have the inhibitory effect on AR through NF-κB pathway by targeting PARP.. In summary, we have shown that NGR-PM-SHI could be a novel strategy for targeted treating allergic rhinitis through the NF-κB pathway by targeting PARP.

Topics: Animals; Dendritic Cells; Disease Models, Animal; Mice; Mice, Inbred BALB C; Micelles; Naphthoquinones; Nasal Mucosa; NF-kappa B; Ovalbumin; Poly(ADP-ribose) Polymerase Inhibitors; Polyesters; Polyethylene Glycols; Rhinitis, Allergic

Shikonin is an ointment produced from Lithospermun erythrorhizon which has been used in traditional medicine both in Europe and Asia for wound healing and is associated with anti-inflammatory properties. The goal of this work is to assess the analgesic properties of Shikonin in the CFA-induced inflammation model of pain. Rats were subjected to inflammation of the hind paw by CFA injection with a preventive injection of Shikonin and compared to either a control group or to a CFA-inflamed group with the vehicle drug solution. Inflammation of the hind paw by CFA was assessed by measurement of the dorsal to plantar diameter. Mechanical thresholds were established by means of the Von Frey filaments which are calibrated filaments that exert a defined force. Finally, the spinal cord of the studied animals was extracted to analyse the microglia population through immunohistochemistry using the specific marker Iba-1. Our results show that Shikonin reduces the paw oedema caused by CFA inflammation. Subsequently, there is a concomitant restoration of the mechanical thresholds reduced by CFA hind paw injection. Additionally, spinal microglia is activated after CFA-induced inflammation. Our results show that microglia is inhibited by Shikonin and has concomitant restoration of the mechanical thresholds. Our findings demonstrate for the first time that Shikonin inhibits microglia morphological changes and thereby ameliorates pain-like behaviour elicited by mechanical stimulation.

Topics: Animals; Disease Models, Animal; Hyperalgesia; Inflammation; Microglia; Naphthoquinones; Pain; Rats; Spinal Cord

Inflammatory bowel disease (IBD) represents a chronic inflammation of the gastrointestinal tract characterized by an overreaction of immune responses and damage at the intestinal mucosal barrier. P-glycoprotein (P-gp) plays a key role to protect the intestinal barrier from xenobiotic accumulation and suppressing excessive immune responses. Therefore, induction/activation of P-gp function could serve as a novel therapeutic target to treat IBD. This study aimed to evaluate the potential therapeutic values of naphthoquinone derivatives (NQ-1 - NQ-8) as P-gp modulators to counterbalance intestinal inflammation. The data indicate that NQ-2, NQ-3, and NQ-4 act as P-gp inducers/activators and are recognized as substrates for P-gp. The three derivatives possess anti-inflammatory effects mediated by suppression of NF-κB and HDAC6 activity in Caco2 monolayer cells. Besides, they reversed LPS-induced intestinal barrier dysfunction by enhancing the expression of P-gp and ZO-1 tight junction proteins in a Caco-2 spheroid model. NQ-2, NQ-3, and NQ-4 showed a robust inhibitory effect on IL-1β maturation in LPS-primed THP-1 cells. This effect may contribute to alleviate the inflammatory cascades associated with IBD. Distinctively, NQ-2 and NQ-3 exerted anti-NLRP3 inflammasome activity evidenced by the inhibition of CASP-1 activity and the promotion of autophagy. Both compounds induced disruptions of the microtubule network in transfected U2OS-GFP-α-tubulin cells. Treatment with NQ-2 remarkably attenuated dextran sulfate sodium (DSS)-induced colitis in rats by suppressing changes in colon length, colon mass index, and intestinal histopathology scores. Thus, 1,4-naphthoquinone derivatives such as NQ-2 may provide potential therapeutic anti-inflammatory effects for IBD patients and for other NLRP3-associated inflammatory diseases.

Topics: Animals; Anti-Inflammatory Agents; ATP Binding Cassette Transporter, Subfamily B; Caco-2 Cells; Colitis; Colon; Dextran Sulfate; Disease Models, Animal; Humans; Inflammation; Inflammatory Bowel Diseases; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Naphthoquinones; Rats

Plumbagin, a natural bicyclic naphthoquinone, has diverse pharmacological properties and biological benefits against a number of disorders, including liver disease. Though plumbagin's hepatoprotective potential attracts attention, currently no experimental evidence exists on its effectiveness against cholestatic liver injury. The present study investigated its hepatoprotection in the rat model of extrahepatic cholestasis using Bile Duct Ligation (BDL). We found that daily plumbagin supplementation protected the liver from cholestatic damage. Hepatoprotective actions of plumbagin were accompanied by reduction of Transforming Growth Factor β1 (TGF-β1)/Smad, High Mobility Group Box-1 (HMGB1)/Toll-Like Receptor-4 (TLR4), Hypoxia-Inducible Factor-1α (HIF-1α), Aryl Hydrocarbon Receptor (AhR), Heat Shock Protein 90 (HSP90), caveolin-1, NF-κB/AP-1, Dynamin Related Protein-1 (Drp1), malondialdehyde level, Interleukin-1β (IL-1β), p62/SQSTM1, and caspase 3 as well as increase of Farnesoid X Receptor (FXR), bile acid efflux transporters, glutathione, LC3-II, Beclin1, and nuclear NF-E2-Related Factor-2 (Nrf2) and Transcription Factor EB (TFEB). The activation of nuclear Nrf2 caused by plumbagin correlated well with the improvement in bile acid retention, liver histology, serum biochemical, ductular reaction, mitochondrial dysfunction, oxidative stress, inflammation, apoptosis, impaired autophagy, and fibrosis, involving interplay of multiple intracellular signaling pathways. Plumbagin is likely a candidate drug to protect the liver from cholestatic damages. Despite the promising findings from this study, translational implication of plumbagin on cholestatic liver injury warrants further investigation.

Topics: Animals; Bile Acids and Salts; Bile Ducts; Cholestasis; Disease Models, Animal; Ligation; Liver; Naphthoquinones; NF-E2-Related Factor 2; Rats

Colorectal cancer (CRC) and inflammatory bowel disease (IBD) are the most common diseases of human digestive system. Nowadays, the influence of the inflammatory microenvironment on tumorigenesis has become a new direction, and the exploration of relative molecular mechanism will facilitate the discovery and identification of novel potential anti-cancer molecules.. Natural shikonin (SK) and acetyl-shikonin (acetyl-SK) was administered to azoxymethane (AOM)/dextran sodium sulphate (DSS)-induced colitis-associated colorectal cancer (CAC) mice model by gavage to investigate their therapeutic effects. Moreover, fresh feces and colon tissues were collected for determining the function of SK and acetyl-SK on the gut microbes and protein expression, respectively.. Both SK and acetyl-SK decreased AOM/DSS-induced CAC, and regulated the intestinal flora structure in CAC mouse model. They, especially SK, improved species richness, evenness and diversity of intestinal flora, recovered the upregulated ratio of Firmicutes to Bacteroidota (F/B ratio) which symbolizes gut microbiota dysbiosis. SK and its derivative increased the beneficial bacteria g__norank_f__Muribaculaceae, Lactobacillus, Lachnospiraceae_NK4A136_Group, and reduced those harmful ones including Ileibacterium and Coriobacteriaceae UCG-002. Notably, AOM/DSS caused significant increase in the abundance of Ileibaterium valens and g__norank_f__norank_o__Clostridia_UCG-014, which were not previously reported in studies of colonic inflammation or cancer, and the disorder was reversed by 20 mg/kg of SK. In our current study, the action of SK and acetyl-SK is dose-dependent, and 20 mg/kg SK exhibited the most effective functions, even better than the positive drug mesalazine. Moreover, differential proteomics and ELISA results showed that SK could recover the increase of pro-inflammatory cytokines (including IL-1β, IL-6 and TNF-α), the upregulation of pyruvate kinase isozyme type M2 (PKM2) and some other proteins (mainly concentrated in transcriptional mis-regulation in cancer and IL-17 signaling pathways), and the downregulation of Aldh1b1-Acc3-Maoa and Μgt2b34-Aldh1a1-Aldh1a7 involved in Wnt/β-catenin signaling pathway.. Our study identified SK and acetyl-SK, especially SK, as potential preventive agents for CAC through regulating both gut microbes and pathways involved in inflammation and cancer such as Wnt/β-catenin signaling pathway.

Topics: Animals; Azoxymethane; Bacteroidetes; Colitis; Colitis-Associated Neoplasms; Colorectal Neoplasms; Dextran Sulfate; Disease Models, Animal; Firmicutes; Humans; Inflammation; Mice; Mice, Inbred C57BL; Naphthoquinones; Tumor Microenvironment

Parkinson's disease (PD) is the second most common neurodegenerative disorder. Shikonin plays protective roles in age-associated diseases. Therefore, we investigate the biological functions of shikonin and its mechanisms involved in PD pathogenesis. The neurotoxin, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) was used to mimic PD-like conditions in animal models. The learning and memory capacities were assessed by Morris water-maze test, pole test, locomotor activity test and rotarod test. Neuroinflammation was determined by measuring the levels of tumour necrosis factor α (TNF-α), interleukin (IL)-1β, IL-6, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). The quantification of superoxide dismutase, malondialdehyde and glutathione in substantia nigra was performed to estimate oxidative damage. Histopathologic changes were examined by haematoxylin and eosin staining. Immunofluorescence staining was conducted to determine the activation of astrocytes, tyrosine hydroxylase (TH)-positive neurons, and nuclear translocation of p65. Immunohistochemistry was performed to evaluate dopamine transporter (DAT)-positive neurons. Protein levels were measured by western blotting. Shikonin alleviates the cognitive and behavioural impairments. The death of dopaminergic neurons in nigra was attenuated by shikonin. The MPTP-induced neuroinflammation and oxidative stress in substantia nigra were alleviated by shikonin administration. Shikonin ameliorated the neuronal damage in nigra and inhibited the activation of astrocyte. Shikonin modulated the protein kinase B (Akt)/extracellular regulated kinase (ERK)/c-Jun N-terminal kinase (JNK)/nuclear factor κB (NF-κB) pathways. Shikonin ameliorates dopaminergic neuronal apoptosis by inhibiting oxidative stress and neuroinflammation via the Akt/ERK/JNK/NF-κB pathways in PD. The study has several limitations. First, in a previous study, levels of phosphorylated ERK were increased by MPTP. In our current study, we observed decreased p-ERK in nigra following MPTP treatment. Therefore, further investigation in the mechanisms of shikonin against PD progression is required. Second, the biological functions of shikonin need more exploration, including mitochondrial function and autophagy. Moreover, specific molecular targets for shikonin remain uncertain.

Topics: 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine; Animals; Cyclooxygenase 2; Disease Models, Animal; Dopamine Plasma Membrane Transport Proteins; Glutathione; Interleukin-6; JNK Mitogen-Activated Protein Kinases; Malondialdehyde; Mice; Mice, Inbred C57BL; Naphthoquinones; Neuroinflammatory Diseases; Neurotoxins; NF-kappa B; Nitric Oxide Synthase Type II; Oxidative Stress; Parkinson Disease; Proto-Oncogene Proteins c-akt; Superoxide Dismutase; Tumor Necrosis Factor-alpha; Tyrosine 3-Monooxygenase

Shikonin is the main component of the traditional Chinese medicine comfrey, which can inhibit the activity of PKM2 by regulating glycolysis and ATP production. Rheumatoid arthritis synovial cells (RA-FLSs) have been reported to increase glycolytic activity and have other similar hallmarks of metabolic activity. In this study, we investigated the effects of shikonin on glycolysis, mitochondrial function, and cell death in RA-FLSs. The results showed that shikonin induced apoptosis and autophagy in RA-FLSs by activating the production of reactive oxygen species (ROS) and inhibiting intracellular ATP levels, glycolysis-related proteins, and the PI3K-AKT-mTOR signaling pathway. Shikonin can significantly reduce the expression of apoptosis-related proteins, paw swelling in rat arthritic tissues, and the levels of inflammatory factors in peripheral blood, such as TNF-α, IL-6, IL-8, IL-10, IL-17A, and IL-1β while showing less toxicity to the liver and kidney.

Topics: Adenosine Triphosphate; Animals; Anti-Inflammatory Agents; Apoptosis; Arthritis, Rheumatoid; Autophagy; Cell Line; Disease Models, Animal; Energy Metabolism; Humans; Interleukins; Male; Naphthoquinones; Phosphatidylinositol 3-Kinase; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Signal Transduction; Synoviocytes; TOR Serine-Threonine Kinases

Echinochrome A (Ech A, 7-ethyl-2,3,5,6,8-pentahydroxy-1,4-naphthoquinone) has been known to exhibit anti-oxidative and anti-inflammatory effects. However, no study has been carried out on the efficacy of Ech A against skin photoaging; this process is largely mediated by oxidative stress. Six-week-old male SKH-1 hairless mice (

Topics: Animals; Aquatic Organisms; Collagen; Disease Models, Animal; Male; Mast Cells; Mice; Mice, Hairless; Naphthoquinones; Protective Agents; Skin Aging; Ultraviolet Rays; Water Loss, Insensible

Choroidal neovascularization (CNV), a feature of neovasular age-related macular degeneration (AMD), acts as a leading cause of vision loss in the elderly. Shikonin (SHI), a natural bioactive compound extracted from Chinese herb radix arnebiae, exerts anti-inflammatory and anti-angiogenic roles and also acts as a potential pyruvate kinase M2 (PKM2) inhibitor in macrophages. The major immune cells macrophages infiltrate the CNV lesions, where the production of pro-angiognic cytokines from macrophage facilitates the development of CNV. PKM2 contributes to the neovascular diseases. In this study, we found that SHI oral gavage alleviated the leakage, area and volume of mouse laser-induced CNV lesion and inhibited macrophage infiltration without ocular cytotoxicity. Moreover, SHI inhibited the secretion of pro-angiogenic cytokine, including basic fibroblast growth factor (FGF2), insulin-like growth factor-1 (IGF1), chemokine (C-C motif) ligand 2 (CCL2), placental growth factor and vascular endothelial growth factor (VEGF), from primary human macrophages by down-regulating PKM2/STAT3/CD163 pathway, indicating a novel potential therapy strategy for CNV.

Topics: Angiogenesis Inducing Agents; Angiogenesis Inhibitors; Animals; Anti-Inflammatory Agents, Non-Steroidal; Antigens, CD; Antigens, Differentiation, Myelomonocytic; Blotting, Western; Cells, Cultured; Choroidal Neovascularization; Chromatography, High Pressure Liquid; Coloring Agents; Cytokines; Disease Models, Animal; Drugs, Chinese Herbal; Enzyme-Linked Immunosorbent Assay; Fluorescein Angiography; Humans; In Situ Nick-End Labeling; Indocyanine Green; Macrophages; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; Phosphorylation; Pyruvate Kinase; Receptors, Cell Surface; STAT3 Transcription Factor

Cancer-associated thrombosis is the second-leading cause of mortality in patients with cancer and presents a poor prognosis, with a lack of effective treatment strategies. NAD(P)H quinone oxidoreductase 1 (NQO1) increases the cellular nicotinamide adenine dinucleotide (NAD

Topics: Animals; Breast Neoplasms; Cell Line, Tumor; Disease Models, Animal; Extracellular Traps; Female; Mice; Mice, Inbred BALB C; NAD; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Sirtuin 1; Thrombophilia; Thromboplastin; Thrombosis

Atopic dermatitis (AD) is a chronic inflammatory skin disease in which skin barrier dysfunction leads to dryness, pruritus, and erythematous lesions. AD is triggered by immune imbalance and oxidative stress. Echinochrome A (Ech A), a natural pigment isolated from sea urchins, exerts antioxidant and beneficial effects in various inflammatory disease models. In the present study, we tested whether Ech A treatment alleviated AD-like skin lesions. We examined the anti-inflammatory effect of Ech A on 2,4-dinitrochlorobenzene (DNCB)-induced AD-like lesions in an NC/Nga mouse model. AD-like skin symptoms were induced by treatment with 1% DNCB for 1 week and 0.4% DNCB for 5 weeks in NC/Nga mice. The results showed that Ech A alleviated AD clinical symptoms, such as edema, erythema, and dryness. Treatment with Ech A induced the recovery of epidermis skin lesions as observed histologically. Tewameter

Topics: Animals; Anti-Inflammatory Agents; Aquatic Organisms; Dermatitis, Atopic; Disease Models, Animal; Interleukin-3; Male; Mice; Mice, Inbred Strains; Naphthoquinones; Sea Urchins; Skin; Water Loss, Insensible

Shikonin is the major active component in

Topics: Acute Lung Injury; Animals; Anti-Inflammatory Agents, Non-Steroidal; Apoptosis; Bronchoalveolar Lavage Fluid; Caspase 3; Cytokines; Disease Models, Animal; DNA Fragmentation; Inflammation; Lipopolysaccharides; Male; Mice, Inbred C57BL; Myeloid Cell Leukemia Sequence 1 Protein; Naphthoquinones; Neutrophil Infiltration; Neutrophils; Poly(ADP-ribose) Polymerases; Teichoic Acids; Tumor Suppressor Protein p53

Topics: Animals; Anti-Bacterial Agents; Bacterial Proteins; beta-Lactamase Inhibitors; beta-Lactamases; Disease Models, Animal; Humans; Kinetics; Molecular Docking Simulation; Naphthoquinones; Staphylococcal Infections; Staphylococcus aureus; Streptomyces

The role and significance of liver-derived cytokines in cancer-associated cachexia syndrome remain elusive. Here we report that combinatorial counterbalances of the leptin and Igf1 signaling pathways in hepatocellular carcinoma (HCC) models significantly relieves cachexia. Double transgenic zebrafish models of HCC that stably displayed focal lesions, anorexia, and wasting of adipose and muscle tissues were first generated. Knockout of lepr or mc4r from these zebrafish partially restored appetite and exerted moderate or no effect on tissue wasting. However, genetic replenishment of Igf1 in a lepr-mutant background effectively relieved the cachexia-like phenotype without affecting tumor growth. Similarly, administration of napabucasin, a Stat3/Socs3 inhibitor, on the zebrafish HCC model, mammalian cell lines with exogenous IGF1, and two mouse xenograft models restored insulin sensitivity and rescued the wasting of nontumor tissues. Together, these results describe the synergistic impact of leptin and Igf1 normalization in treating certain HCC-associated cachexia as a practical strategy. SIGNIFICANCE: Disruption of leptin signaling with normalized Igf1 expression significantly rescues anorexia, muscle wasting, and adipose wasting in Ras- and Myc-driven zebrafish models of HCC.

Topics: 3T3-L1 Cells; Adipose Tissue; Animals; Animals, Genetically Modified; Benzofurans; Cachexia; Carcinoma, Hepatocellular; Cells, Cultured; Cytokines; Disease Models, Animal; Drug Synergism; HEK293 Cells; Hep G2 Cells; Humans; Insulin Resistance; Insulin-Like Growth Factor I; Leptin; Liver; Liver Neoplasms; Mice; Muscular Atrophy; Naphthoquinones; Receptors, Leptin; Signal Transduction; Wasting Syndrome; Xenograft Model Antitumor Assays; Zebrafish

Gestational diabetes mellitus is a risk factor for congenital heart defects. The article aimed to investigate the expression and roles of MST1, YAP1, Last1/2 and Survivin in modulating HG-induced cardiomyocyte apoptosis and maternal diabetes-induced heart abnormality.. Diabetes mellitus was induced in rats using streptozotocin. The protein expression and phosphorylation analysis in fetal heart tissue was assessed by western blot and immunohistochemical staining. Hoechst 33342 staining assay was performed to explore H9C2 apoptosis. The gene and protein expression in H9C2 cells was assessed by quantitative PCR and western blot. Knockdown of gene expression was assessed by RNA interference.. Our results revealed that increased MST1 protein levels in the heart tissues of the offspring of diabetic rats in vivo and in H9C2 cardiomyocytes under HG treatment in vitro, respectively. Knockdown and overexpression experiments showed that MST1 played a key role in mediating HG-induced apoptosis in cardiomyocytes. Downregulation of YAP1 was associated with HG-induced, MST1-mediated cardiomyocyte apoptosis. Further study showed that MST1 downregulated the protein level of YAP1 through mediation of YAP1 phosphorylation on Ser127 and Ser397; this process also required LATS1/2 participation. MST1 overexpression increased the phosphorylation levels of LATS1/2, which were also shown to be increased in the heart tissues of diabetic offspring. We also found that YAP1 mediated the expression of Survivin during HG-induced apoptosis, and the Survivin-inhibitor YM155 partially inhibited the role of YAP1 in suppressing apoptosis induced by HG in cardiomyocytes.. These findings reveal a regulatory mechanism of MST1/YAP1/Survivin signaling in modulating cardiomyocyte apoptosis in vitro and maternal diabetes-induced congenital heart defects in vivo.

Topics: Animals; Apoptosis; Cell Line; Diabetes Mellitus, Experimental; Disease Models, Animal; Down-Regulation; Glucose; Imidazoles; Intracellular Signaling Peptides and Proteins; Myocytes, Cardiac; Naphthoquinones; Phosphorylation; Protein Serine-Threonine Kinases; Rats; Streptozocin; Survivin; YAP-Signaling Proteins

Depression and anxiety disorders contribute to the global disease burden. Ursolic acid (UA), a natural compound present in many vegetables, fruits and medicinal plants, was tested in vivo for its effect on (1) enhancing resistance to stress and (2) its effect on life span.. The compound was tested for its antioxidant activity in C. elegans. Stress resistance was tested in the heat and osmotic stress assay. Additionally, the influence on normal life span was examined. RT-PCR was used to assess possible serotonin targets.. UA prolonged the life span of C. elegans. Additionally, UA significantly lowered reactive oxygen species (ROS). Molecular docking studies, PCR analysis and microscale thermophoresis (MST) supported the results that UA acts through serotonin receptors to enhance stress resistance.. Considering the urgent need for new and safe medications in the treatment of depression and anxiety disorders, our results indicate that UA may be a promising new drug candidate.

Topics: Animals; Antioxidants; Caenorhabditis elegans; Depression; Disease Models, Animal; Hot Temperature; Longevity; Models, Molecular; Molecular Docking Simulation; Mutation; Naphthoquinones; Osmotic Pressure; Reactive Oxygen Species; Receptors, Serotonin; Serotonin; Stress, Physiological; Triterpenes; Ursolic Acid

Juglone, mainly isolates from the green walnut husks of Juglans mandshurica, exhibits anti-cancer and anti-inflammaroty activities. But its protection on ulcerative colitis (UC) has never been explored. In this study, we first evaluated whether juglone ameliorated UC, and investigated its effects on gut microbiota and Th17/Treg balance in DSS-induced UC mice model. The model was established by administrating 2.7% DSS for seven days. Juglone was given daily by gavage for ten days, once a day. The disease activity index (DAI) decrease and pathological characteristics improvement demonstrated that the UC in mice was alleviated by juglone. Juglone treatment significantly inhibited the protein levels of IL-6, TNF-α and IL-1β, improved the protein expression of IL-10. In addition, juglone altered microbial diversity and gut microbiota composition, including the enhancement of the ratio of Firmicutes to Bacteroidota and the abundance of Actinobacteriota, and decrease of the abundance of Verrucomicrobiota. Juglone treatment also inhibited the protein expressions of IL-6, STAT3 and RORγt, meanwhile improved the protein level of FOXP3. Furthermore, juglone inhibited Th17 development and increased Treg generation, beneficial to Th17/Treg balance. Together, we herein provided the first evidence to support that juglone, especially the high dose, possibly protected mice against UC by modulating gut microbiota and restoring Th17/Treg homeostasis.

Topics: Animals; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Drug Evaluation, Preclinical; Gastrointestinal Microbiome; Humans; Intestinal Mucosa; Male; Mice; Naphthoquinones; T-Lymphocytes, Regulatory; Th17 Cells

Scleroderma is an autoimmune disease caused by the abnormal regulation of extracellular matrix synthesis and is activated by non-regulated inflammatory cells and cytokines. Echinochrome A (EchA), a natural pigment isolated from sea urchins, has been demonstrated to have antioxidant activities and beneficial effects in various disease models. The present study demonstrates for the first time that EchA treatment alleviates bleomycin-induced scleroderma by normalizing dermal thickness and suppressing collagen deposition in vivo. EchA treatment reduces the number of activated myofibroblasts expressing α-SMA, vimentin, and phosphorylated Smad3 in bleomycin-induced scleroderma. In addition, it decreased the number of macrophages, including M1 and M2 types in the affected skin, suggesting the induction of an anti-inflammatory effect. Furthermore, EchA treatment markedly attenuated serum levels of inflammatory cytokines, such as tumor necrosis factor-α and interferon-γ, in a murine scleroderma model. Taken together, these results suggest that EchA is highly useful for the treatment of scleroderma, exerting anti-fibrosis and anti-inflammatory effects.

Topics: Actins; Animals; Anti-Inflammatory Agents; Bleomycin; Collagen; Cytokines; Disease Models, Animal; Fibrosis; Humans; Inflammation Mediators; Macrophages; Male; Mice; Mice, Inbred C57BL; Myofibroblasts; Naphthoquinones; Phosphorylation; RAW 264.7 Cells; Scleroderma, Systemic; Skin; Smad3 Protein; Vimentin

Inflammatory bowel diseases (IBDs) are serious disorders of which the etiologies are not, as yet, fully understood. In this study, Peptidyl-prolyl cis-trans isomerase NIMA-interacting 1 (Pin1) protein was shown to be dramatically upregulated in the colons of dextran sodium sulfate (DSS)-induced ulcerative colitis model mice. Interestingly,

Topics: Animals; Anti-Inflammatory Agents; Colitis; Colon; Cytokines; Dextran Sulfate; Disease Models, Animal; Enzyme Inhibitors; Inflammation Mediators; Intestinal Mucosa; Macrophages; Mice, Inbred C57BL; Mice, Knockout; Naphthoquinones; NIMA-Interacting Peptidylprolyl Isomerase

Alkannin-based pharmaceutical formulations for improving wound healing have been on the market for several years. However, detailed molecular mechanisms of their action have yet to be elucidated. Here, we investigated the potential roles of AAN-II in improving the healing of pressure-induced venous ulcers using a rabbit model generated by combining deep vein thrombosis with a local skin defect/local skin defect. The extent of healing was evaluated using hematoxylin and eosin (HE) or vimentin staining. Rabbit skin fibroblasts were cultured for AAN-II treatment or TGFB1-sgRNA lentivirus transfection. ELISA was used to evaluate the levels of various cytokines, including IL-1β, IL-4, IL-6, TNF-α, VEGF, bFGF, TGF-β and PDGF. The protein levels of TGF-β sensors, including TGF-β, Smad7 and phosphor-Smad3, and total Smad3, were assayed via western blotting after TGF-β knockout or AAN-II treatment. The results show that, for this model, AAN-II facilitates ulcer healing by suppressing the development of inflammation and promoting fibroblast proliferation and secretion of proangiogenic factors. AAN-II enhances the activation of the TGF-β1-Smad3 signaling pathway during skin ulcer healing. In addition, the results demonstrate that AAN-II and TGF-β have synergistic effects on ulcer healing. Our findings indicate that AAN-II can promote healing of pressure-induced venous skin ulcers via activation of TGF-β-Smad3 signaling in fibroblast cells and provide evidence that could be used in the development of more effective treatments.

Topics: Animals; Boraginaceae; Disease Models, Animal; Female; Naphthoquinones; Pressure; Rabbits; Signal Transduction; Smad3 Protein; Transforming Growth Factor beta1; Varicose Ulcer; Wound Healing

Benzoxepane derivatives were designed and synthesized, and one hit compound emerged as being effective in vitro with low toxicity. In vivo, this hit compound ameliorated both sickness behavior through anti-inflammation in LPS-induced neuroinflammatory mice model and cerebral ischemic injury through anti-neuroinflammation in rats subjected to transient middle cerebral artery occlusion. Target fishing for the hit compound using photoaffinity probes led to identification of PKM2 as the target protein responsible for anti-inflammatory effect of the hit compound. Furthermore, the hit exhibited an anti-neuroinflammatory effect in vitro and in vivo by inhibiting PKM2-mediated glycolysis and NLRP3 activation, indicating PKM2 as a novel target for neuroinflammation and its related brain disorders. This hit compound has a better safety profile compared to shikonin, a reported PKM2 inhibitor, identifying it as a lead compound in targeting PKM2 for the treatment of inflammation-related diseases.

Topics: Animals; Anti-Inflammatory Agents; Dibenzoxepins; Disease Models, Animal; Infarction, Middle Cerebral Artery; Interleukin-1beta; Ischemic Stroke; Lipopolysaccharides; Macrophages; Mice; Microglia; Naphthoquinones; NLR Family, Pyrin Domain-Containing 3 Protein; Pyruvate Kinase; Rats; RAW 264.7 Cells; Structure-Activity Relationship; Tumor Necrosis Factor-alpha

Topics: Animals; Disease Models, Animal; Estradiol; Extracellular Matrix; Female; Humans; Naphthoquinones; Ovariectomy; Rats; Rats, Sprague-Dawley; Vocal Cords; Vocalization, Animal

Chagas disease, which is caused by the protozoan Trypanosoma cruzi, is endemic to Latin America and mainly affects low-income populations. Chemotherapy is based on two nitrocompounds, but their reduced efficacy encourages the continuous search for alternative drugs. Our group has characterised the trypanocidal effect of naphthoquinones and their derivatives, with naphthoimidazoles derived from β-lapachone (N1, N2 and N3) being the most active in vitro.. In the present work, the effects of N1, N2 and N3 on acutely infected mice were investigated.. in vivo activity of the compounds was assessed by parasitological, biochemical, histopathological, immunophenotypical, electrocardiographic (ECG) and behavioral analyses.. Naphthoimidazoles led to a decrease in parasitaemia (8 dpi) by reducing the number of bloodstream trypomastigotes by 25-50% but not by reducing mortality. N1 protected mice from heart injury (15 dpi) by decreasing inflammation. Bradycardia was also partially reversed after treatment with N1 and N2. Furthermore, the three compounds did not reverse hepatic and renal lesions or promote the improvement of other evaluated parameters.. N1 showed moderate trypanocidal and promising immunomodulatory activities, and its use in combination with benznidazole and/or anti-arrhythmic drugs as well as the efficacy of its alternative formulations must be investigated in the near future.

Topics: Acute Disease; Animals; Anti-Inflammatory Agents; Chagas Disease; Disease Models, Animal; Electrocardiography; Male; Mice; Naphthoquinones; Nitroimidazoles; Parasitemia; Time Factors; Trypanocidal Agents

LQB 118, a hydride molecule, has been described as an antineoplastic and antiparasitic drug. Recently, LQB118 was also shown to display anti-inflammatory properties using an LPS-induced lung inflammation model. However, LQB 118 effects on the inflammatory response induced by zymosan has not been demonstrated. In this study, swiss mice were LQB 118 intraperitoneally (i.p.) treated and zymosan was used to induce peritoneal inflammation. Peritoneal fluid was collected and used for cell counting and proinflammatory cytokines quantification (IL-1β, IL-6, and TNF-α) by immunoenzymatic assay (ELISA). For in vitro studies, peritoneal macrophages zymosan-stimulated were used. Results demonstrated that LQB 118 treatment reduced polymorphonuclear cell migration and TNF-α, IL-1β, and IL-6 levels in the peritoneal cavity. In macrophages, LQB 118 treatment display no cytotoxic effect and is also able to reduce cytokines levels. To investigate LQB 118 putative mechanism of action, TLR2, CD69, and P-p38 MAPK expression were evaluated. LQB 118 treatment reduced CD69 expression and p38 phosphorylation induced by zymosan. Furthermore, LQB 118 was able to negatively modulate TLR2 expression in the presence of inflammatory stimulus. Thus, our study provide new evidences for the mechanisms related to the anti-inflammatory effect of LQB 118 in vivo and in vitro.

Topics: Animals; Anti-Inflammatory Agents; Antineoplastic Agents; Cells, Cultured; Cytokines; Disease Models, Animal; Female; Humans; Inflammation; Inflammation Mediators; Macrophages; Mice; Naphthoquinones; Peritoneum; Peritonitis; Pterocarpans; Zymosan

Postmenopausal osteoporosis results from estrogen withdrawal and is characterized mainly by bone resorption. Shikonin is a bioactive constitute of Chinese traditional herb which plays a role in antimicrobial and antitumor activities. The study was designed to investigate the role of shikonin on postmenopausal osteoporosis and explore its underlying mechanisms.. Immunofluorescence staining was performed to evaluate the effects of shikonin on actin ring formation. The expression levels of the nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) pathway were determined by Western blot analysis. To determine whether shikonin influences the receptor activator of nuclear factor-κB ligand (RANKL)-induced association between receptor activator of NF-κB (RANK) and tumor necrosis factor receptor associated factor 6 (TRAF6), immunofluorescence staining and immunoprecipitation experiments were performed. During our validation model, histomorphometric examination and micro-computed tomography (CT) were conducted to assess the morphology of osteoporosis.. Shikonin prevented bone loss by inhibiting osteoclastogenesis in vitro and improving bone loss in ovariectomized mice in vivo. At the molecular level, Western blot analysis indicated that shikonin inhibited the phosphorylation of inhibitor of NF-κB (IκB), P50, P65, extracellular regulated protein kinases (ERK), c-Jun N-terminal kinase (JNK), and P38. Interaction of TRAF6 and RANK was prevented, and downstream MAPK and NF-κB signaling pathways were downregulated.. Osteoclastic bone resorption was reduced in the presence of shikonin in vitro and in vivo. Shikonin is a promising candidate for treatment of postmenopausal osteoporosis.

Topics: Animals; Biomarkers; Bone Resorption; Cell Differentiation; Cell Survival; Disease Models, Animal; Disease Susceptibility; Female; Fluorescent Antibody Technique; Gene Expression Regulation; Humans; Immunohistochemistry; Mice; Mitogen-Activated Protein Kinases; Models, Biological; Naphthoquinones; NF-kappa B; Osteoclasts; Osteogenesis; Osteoporosis, Postmenopausal; Ovariectomy; Protein Binding; RANK Ligand; Receptor Activator of Nuclear Factor-kappa B; Signal Transduction; TNF Receptor-Associated Factor 6; X-Ray Microtomography

Shikonin, a natural plant pigment, is known to have anti-obesity activity and to improve insulin sensitivity. This study aimed to examine the effect of shikonin on hepatic steatosis, focusing on the AMP-activated protein kinase (AMPK) and energy expenditure in Hepa 1-6 cells and in high-fat fed mice. Shikonin increased AMPK phosphorylation in a dose- and time-dependent manner, and inhibition of AMPK with compound C inhibited this activation. In an oleic acid-induced steatosis model in hepatocytes, shikonin suppressed oleic acid-induced lipid accumulation, increased AMPK phosphorylation, suppressed the expression of lipogenic genes, and stimulated fatty acid oxidation-related genes. Shikonin administration for four weeks decreased body weight gain and the accumulation of lipid droplets in the liver of high-fat fed mice. Furthermore, shikonin promoted energy expenditure by activating fatty acid oxidation. In addition, shikonin increased the expression of PPARγ coactivator-1α (PGC-1α), carnitine palmitoyltransferase-1 (CPT1) and other mitochondrial function-related genes. These results suggest that shikonin attenuated a high fat diet-induced nonalcoholic fatty liver disease by stimulating fatty acid oxidation and energy expenditure via AMPK activation.

Topics: AMP-Activated Protein Kinases; Animals; Anti-Inflammatory Agents, Non-Steroidal; Carnitine O-Palmitoyltransferase; Cells, Cultured; Diet, High-Fat; Disease Models, Animal; Dose-Response Relationship, Drug; Energy Metabolism; Fatty Liver; Gene Expression; Lipid Metabolism; Mice; Naphthoquinones; Oxidation-Reduction; Peroxisome Proliferator-Activated Receptor Gamma Coactivator 1-alpha; Phosphorylation; Phytotherapy

Psoriasis is a chronic inflammatory skin disease characterized by well‑defined scaly papules and plaques. Interleukin (IL)‑17 is involved in its pathogenesis and promotes the proliferation of epidermal keratinocytes through signal transducer and activator of transcription 3 (STAT3) activation. Shikonin, a natural naphthoquinone isolated from Lithospermum erythrorhizon, possesses anti‑inflammatory and immunosuppressive properties and can suppress IL‑17‑induced vascular endothelial growth factor expression by inhibiting the JAK/STAT3 pathway. In the present study, MTS, iCELLigence and RT‑qPCR were used to determine the optimal concentration and duration of IL‑17 or shikonin acting on HaCaT cells. The changes in the expression levels of genes associated with the IL‑6/STAT3 pathway in differentially treated cells were analyzed via RT2Profiler™ PCR Array. Small interfering RNA was used to silence the expression levels of the target gene CCAAT/enhancer‑binding protein δ (CEBPD). Western blotting and immunohistochemistry were used to evaluate the effect of shikonin on imiquimod‑induced psoriasis in mice and the expression levels of CEBPD. Shikonin reversed IL‑17‑mediated downregulation of the tumor suppressor CEBPD in HaCaT cells. Moreover, low levels of CEBPD in the imiquimod‑induced mouse model of psoriasis were restored by shikonin treatment, which ameliorated excessive keratinocyte proliferation. Taken together, these findings suggest that CEBPD plays a key role in the pathogenesis of psoriasis and can be targeted by shikonin as a potential therapeutic strategy.

Topics: Animals; CCAAT-Enhancer-Binding Protein-delta; Cell Proliferation; Disease Models, Animal; Down-Regulation; HaCaT Cells; Humans; Imiquimod; Interleukin-17; Interleukin-6; Mice; Naphthoquinones; Psoriasis; Signal Transduction; STAT3 Transcription Factor

The purpose of the present study was to clarify whether treatment with YM155, a novel small-molecule inhibitor of survivin, reversed cabazitaxel resistance in castration-resistant prostate cancer (CRPC).. Cabazitaxel resistance was induced in the castration-resistant prostate cancer cell line, 22Rv1-CR. In vitro and in vivo models were used to test the efficacy of YM155 and cabazitaxel.. Survivin gene expression was significantly higher in 22Rv1-CR than its parent cells (22Rv1). In 22Rv1-CR cells, YM155 significantly reduced expression of the survivin gene in a concentration-dependent manner. YM155 alone was poorly effective; however, it significantly enhanced the anticancer effects of cabazitaxel on 22Rv1-CR in vitro and in vivo.. Inhibition of survivin by YM155 overcomes cabazitaxel resistance in CRPC cells.

Topics: Animals; Apoptosis; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Drug Resistance, Neoplasm; Gene Expression Regulation, Neoplastic; Humans; Imidazoles; Male; Mice; Naphthoquinones; Prostatic Neoplasms, Castration-Resistant; RNA, Messenger; Survivin; Taxoids; Xenograft Model Antitumor Assays

Multiple sclerosis is a common autoimmune inflammatory disease of the central nervous system. There are several underlying mechanisms for the pathogenesis of the disease, including inflammation, oligodendrocyte apoptosis and oxidative stress.. The mechanism of action of shikonin was investigated in the C57BL/6 experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis.. The results revealed that EAE induction significantly increased the extent of demyelination in the corpus callosum tissues of the animals, while treatment of the mice with shikonin significantly decreased the extent of demyelination. Real-time polymerase chain reaction-based analysis of the brain samples from the EAE mice revealed significant enhancement in the expression levels of tumour necrosis factor-α (TNF-α), interferon-γ (IFN-γ) and Bax genes as well as a reduction in the expression levels of transforming growth factor-ß (TGF-β) and Bcl2. But, shikonin treatment significantly reduced the expression levels of TNF-α, IFN-γ and Bax. On the other hand, the expression levels of TGF-β and Bcl2 as well as the activity of glutathione peroxidase-1 (GPX-1) enzyme were significantly increased following the shikonin treatment.. This study emphasized the immune-modulatory and antioxidative effects of shikonin, which may have an important healing effect on the severity of EAE.

Topics: Animals; Antioxidants; Apoptosis; bcl-2-Associated X Protein; Corpus Callosum; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Female; Glutathione Peroxidase; Glutathione Peroxidase GPX1; Immunologic Factors; Interferon-gamma; Mice, Inbred C57BL; Naphthoquinones; Oxidative Stress; Proto-Oncogene Proteins c-bcl-2; Transforming Growth Factor beta; Tumor Necrosis Factor-alpha

Sepsis is characterized by a dysregulated immune response to infection characterized by an early hyperinflammatory and oxidative response followed by a subsequent immunosuppression phase. Although there have been some advances in the treatment of sepsis, mortality rates remain high, urging for the search of new therapies.

Topics: Animals; Anti-Inflammatory Agents; Chemoprevention; Cytokines; Disease Models, Animal; Immunosuppression Therapy; Inflammation; Inflammation Mediators; Male; Mice; Naphthoquinones; Oxidative Stress; Sepsis; Survival Rate

Of late, researchers have taken interest in alternative medicines for the treatment of brain ischemic stroke, where full recovery is rarely seen despite advanced medical technologies. Due to its antioxidant activity, Echinochrome A (Ech A), a natural compound found in sea urchins, has acquired attention as an alternative clinical trial source for the treatment of ischemic stroke. The current study demonstrates considerable potential of Ech A as a medication for cerebral ischemic injury. To confirm the effects of Ech A on the recovery of the injured region and behavioral decline, Ech A was administered through the external carotid artery in a rat middle cerebral artery occlusion model after reperfusion. The expression level of cell viability-related factors was also examined to confirm the mechanism of brain physiological restoration. Based on the results obtained, we propose that Ech A ameliorates the physiological deterioration by its antioxidant effect which plays a protective role against cell death, subsequent to post cerebral ischemic stroke.

Topics: Animals; Antioxidants; Apoptosis; Behavior Observation Techniques; Behavior, Animal; Brain; Cell Survival; Disease Models, Animal; Humans; Infarction, Middle Cerebral Artery; Male; Middle Cerebral Artery; Naphthoquinones; Neuroprotective Agents; Oxidative Stress; Rats; Reperfusion Injury; Sea Urchins; Treatment Outcome

Topics: Animals; Antimalarials; Disease Models, Animal; HeLa Cells; Humans; Mice; Molecular Structure; Naphthoquinones; Quinone Reductases; Reactive Oxygen Species; Structure-Activity Relationship; Substrate Specificity

Liver fibrosis is a worldwide clinical challenge during the progression of chronic liver disease to liver cirrhosis. Shikonin is extracted from the root of Lithospermum erythrorhizon with antioxidant, anti-inflammatory, anticancer, and wound-healing properties. The study aims to investigate the protective effect of shikonin on liver fibrosis and its underlying mechanism.. Shikonin significantly inhibited activation of hepatic stellate cells and extracellular matrix formation by downregulating the transforming growth factor-β1 expression and maintaining the normal balance between metalloproteinase-2 and tissue inhibitor of metalloproteinase-1. Shikonin also decreased hepatic stellate cell energy production by inhibiting autophagy.. The results confirmed that shikonin attenuated liver fibrosis by downregulating the transforming growth factor-β1/Smads pathway and inhibiting autophagy.

Topics: Alanine Transaminase; Animals; Anti-Inflammatory Agents, Non-Steroidal; Aspartate Aminotransferases; Autophagy; Disease Models, Animal; Down-Regulation; Extracellular Matrix; Hepatic Stellate Cells; Liver Cirrhosis; Male; Matrix Metalloproteinase 2; Mice; Mice, Inbred C57BL; Naphthoquinones; Signal Transduction; Smad Proteins, Receptor-Regulated; Tissue Inhibitor of Metalloproteinase-1; Transforming Growth Factor beta1

A straightforward method for synthesizing ortho-naphthoquinones was identified using an easily available cobalt-Schiff base complex. Efficient oxidation of phenols to ortho-naphthoquinones was useful in obtaining compounds with potent biological activity for the treatment of acute myeloid leukemia (AML). Among these compounds, the compound 4h effectively inhibited the proliferation of different AML cell lines in vitro. Further in vivo antitumor studies indicated that 4h at 40 mg/kg/d led to tumor regression in led to tumor regression in an MV4-11 xenograft model without evident toxicity. The cobalt-Schiff base complex was found to be an efficient catalyst in the transformation of phenols to ortho-quinones, and the compound 4h represents a potential scaffold to optimize the production of a treatment for AML.

Topics: Animals; Antineoplastic Agents; Cell Line, Tumor; Cell Proliferation; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Humans; Leukemia, Myeloid, Acute; Mice; Molecular Structure; Naphthoquinones; Oxidation-Reduction; Phenols; Structure-Activity Relationship

Topics: Amphotericin B; Animals; Antiprotozoal Agents; Disease Models, Animal; Female; Flow Cytometry; Hep G2 Cells; Humans; Inhibitory Concentration 50; Leishmania infantum; Leishmania mexicana; Leishmaniasis, Cutaneous; Leishmaniasis, Visceral; Liver; Mice; Mice, Inbred BALB C; Naphthoquinones; Parasite Load; Plant Extracts; Random Allocation; RAW 264.7 Cells; Skin; Spleen; Tabebuia

Renal interstitial fibrosis is a common pathological feature of chronic kidney disease that may involve changes of metabolism in kidney cells. In the present study, we first showed that blockade of glycolysis with either dichloroacetate (DCA) or shikonin to target different glycolytic enzymes reduced renal fibrosis in a mouse model of unilateral ureteral obstruction (UUO). Both inhibitors evidently suppressed the induction of fibronectin and collagen type I in obstructed kidneys, with DCA also showing inhibitory effects on collagen type IV and α-smooth muscle actin (α-SMA). Histological examination also confirmed less collagen deposition in DCA-treated kidneys. Both DCA and shikonin significantly inhibited renal tubular apoptosis but not interstitial apoptosis in UUO. Macrophage infiltration after UUO injury was also suppressed. Shikonin, but not DCA, caused obvious animal weight loss during UUO. To determine whether shikonin and DCA worked on tubular cells and/or fibroblasts, we tested their effects on cultured renal proximal tubular BUMPT cells and renal NRK-49F fibroblasts during hypoxia or transforming growth factor-β

Topics: Animals; Apoptosis; Cell Line; Dichloroacetic Acid; Disease Models, Animal; Enzyme Inhibitors; Epithelial Cells; Extracellular Matrix; Fibroblasts; Fibrosis; Glycolysis; Kidney Diseases; Kidney Tubules; Macrophages; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; Signal Transduction; Ureteral Obstruction

This study was performed to evaluate the antidiabetic and wound healing activity of plumbagin in diabetic rats by macroscopical, biochemical, histological, immunohistochemical and molecular methods. Percentage of wound closure and contraction was delayed in diabetic rats when compared to non-diabetic group. There was significant reduction in period of epithelialization, collagen and protein content. Serum insulin level was significantly lowered together with increase in glucose level in diabetic rats. Lipid levels were increased significantly with concomitant decrease in HDL level. The mRNA levels of Nrf2, collagen-1, TGF-β and α-SMA were significantly lowered whereas Keap-1 levels were increased in diabetic rats. The level of lipid peroxides was increased while the levels of antioxidants were lowered significantly. ELISA results reveal upregulated levels of inflammatory markers. Western blot result shows upregulated levels of CD68 and CD163 proteins in wound area of diabetic rats. Histopathological observation revealed increased inflammatory cells infiltration in diabetic control. Immunofluorescent staining and immunohistochemical analysis also displayed delayed wound healing in diabetic groups. Diabetic rats treated with 10% and 20% plumbagin showed increased epithelialization, collagen deposition, increased serum insulin level and increased antioxidant status. Lipid peroxides and lipid levels were lowered significantly with increase in HDL level. Inflammatory markers were lowered, and growth factors expressions were increased markedly. Thus, the results of the study indicated that plumbagin administration could improve wound healing activity and could serve as a potent antidiabetic and anti-inflammatory agent.

Topics: Animals; Antioxidants; Collagen; Collagen Type I; Diabetes Mellitus, Experimental; Disease Models, Animal; Insulin; Male; Naphthoquinones; Rats; Rats, Wistar; Skin; Wound Healing

Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs) accompanying increased production of inflammatory factors and adaptation of the mitochondrial metabolism to a hyperproliferative state. However, all the drugs in clinical use target pulmonary vascular dilatation, which may not be effective for patients with advanced PAH.. We aimed to discover a novel drug for PAH that inhibits PASMC proliferation.. We screened 5562 compounds from original library using high-throughput screening system to discover compounds which inhibit proliferation of PASMCs from patients with PAH (PAH-PASMCs). We found that celastramycin, a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PAH-PASMCs in a dose-dependent manner with relatively small effects on PASMCs from healthy donors. Then, we made 25 analogs of celastramycin and selected the lead compound, which significantly inhibited cell proliferation of PAH-PASMCs and reduced cytosolic reactive oxygen species levels. Mechanistic analysis demonstrated that celastramycin reduced the protein levels of HIF-1α (hypoxia-inducible factor 1α), which impairs aerobic metabolism, and κB (nuclear factor-κB), which induces proinflammatory signals, in PAH-PASMCs, leading to reduced secretion of inflammatory cytokine. Importantly, celastramycin treatment reduced reactive oxygen species levels in PAH-PASMCs with increased protein levels of Nrf2 (nuclear factor erythroid 2-related factor 2), a master regulator of cellular response against oxidative stress. Furthermore, celastramycin treatment improved mitochondrial energy metabolism with recovered mitochondrial network formation in PAH-PASMCs. Moreover, these celastramycin-mediated effects were regulated by ZFC3H1 (zinc finger C3H1 domain-containing protein), a binding partner of celastramycin. Finally, celastramycin treatment ameliorated pulmonary hypertension in 3 experimental animal models, accompanied by reduced inflammatory changes in the lungs.. These results indicate that celastramycin ameliorates pulmonary hypertension, reducing excessive proliferation of PAH-PASMCs with less inflammation and reactive oxygen species levels, and recovered mitochondrial energy metabolism. Thus, celastramycin is a novel drug for PAH that targets antiproliferative effects on PAH-PASMCs.

Topics: Animals; Cells, Cultured; Cytokines; Disease Models, Animal; Drug Evaluation, Preclinical; Energy Metabolism; High-Throughput Screening Assays; Humans; Hypoxia; Hypoxia-Inducible Factor 1, alpha Subunit; Indoles; Male; Metabolome; Mice; Mitochondria; Monocrotaline; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; Naphthoquinones; NF-E2-Related Factor 2; NF-kappa B; Oxidative Stress; Pulmonary Arterial Hypertension; Pulmonary Artery; Pyrroles; Rats; Reactive Oxygen Species; Resorcinols; Transcription Factors

External beam radiotherapy increases the risk of Candida vaginitis in cervical cancer patients, which brings a lot of insufferable influence to their life. Here, we explored the efficacy of alkannin in the treatment of Candida vaginitis after external beam radiotherapy. We exploit thermosensitive hydrogel-mediated alkannin as the topical formulation in a rat model established in our work. Periodic acid-Schiff of vaginas indicated little Candida albicans adhered to the vaginal tissue in treatment group. Additionally, hematoxylin and eosin stain revealed that inflammatory response of high dose alkannin was reduced. Above all, the animal model was first established in our work for the clinical desire. Our results suggested the promising application of alkannin for the disease with satisfying fungicidal activity and anti-inflammatory activity.

Topics: Administration, Topical; Animals; Anti-Infective Agents, Local; Candida albicans; Candidiasis, Vulvovaginal; Disease Models, Animal; Drug Carriers; Female; Hydrogels; Naphthoquinones; Radiotherapy; Rats; Treatment Outcome; Uterine Cervical Neoplasms

The targeted induction of reactive oxygen species (ROS) is a developing mechanism for cancer therapy. LQB-118 is a pterocarpanquinone and ROS-inducing agent with proven antineoplastic activity. Here, LQB-118 efficacy and mechanism of activity, were examined in Prostate Cancer (PCa) cell and tumor models.. LQB-118 treatment triggered PCa cell death and apoptosis. Therapeutic activity was at least partially dependent upon quinone reduction and ROS generation. LQB-118 treatment caused an increase in cellular ROS and lipid peroxidation. Treated cells exhibited elevated levels of NQO1, Nrf2, and SOD1. The miRNAs miR-206, miR-1, and miR-101 targeted and reduced SOD1 expression. The knockdown of SOD1, by siRNA or miRNA, enhanced LQB-118 cytotoxicity. Orally administered LQB-118 treatment significantly reduced the growth of established PCa xenograft tumors.. LQB-118 is a developing and orally active pterocarpanquinone agent that effectively kills PCa cells through quinone reduction and ROS generation. The inhibition SOD1 expression enhances LQB-118 activity, presumably by impairing the cellular antioxidant response.

Topics: Administration, Oral; Animals; Antineoplastic Agents; Cell Line, Tumor; Disease Models, Animal; Humans; Male; Mice; Mice, Nude; Naphthoquinones; Prostate; Prostatic Neoplasms; Pterocarpans; Reactive Oxygen Species; Treatment Outcome

Topics: Animals; Antineoplastic Agents; Carcinoma, Pancreatic Ductal; Cell Transformation, Neoplastic; Ceruletide; Disease Models, Animal; Disease Progression; Gene Knockdown Techniques; Heterografts; Humans; Metaplasia; Mice; Mice, Inbred C57BL; Mice, Nude; Mice, Transgenic; Naphthoquinones; Pancreas; Pancreatic Neoplasms; Precancerous Conditions; Snail Family Transcription Factors; Tumor Cells, Cultured

As important secondary plant metabolites, naphthoquinones exhibit a wide range of biological activities. However, their potential as sustainable alternatives to synthetic acaricides has not been studied. This study for the first time investigates the acaricidal activity of naphthoquinones against Psoroptes cuniculi in vitro. Furthermore, the in vivo activity, the skin irritation effects, the cytotoxicity and the inhibitory activities against mite acetylcholinesterase (AChE) and glutathione S-transferase (GST) of the two compounds that displayed the best insecticidal activity in vitro were evaluated. Among fourteen naphthoquinones and their analogs, juglone and plumbagin were observed to possess the strongest acaricidal activities against P. cuniculi with LC

Topics: Acaricides; Agriculture; Animals; Biological Assay; Cell Survival; Cholinesterase Inhibitors; Disease Models, Animal; Glutathione Transferase; Mite Infestations; Naphthoquinones; Phytochemicals; Psoroptidae; Rabbits; Skin; Survival Analysis; Treatment Outcome

Although plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone) protects against cerebral ischemia and spinal cord injury-induced oxidative stress and inflammation by activating the nuclear factor-erythroid 2-related factor-2 /antioxidant response element (Nrf2/ARE) pathway, its role in the amelioration of neurodegenerative diseases remains unexplored. In the present study, we investigated the effect of plumbagin on Alzheimer's disease (AD)-like condition in mice. The animals were treated intracerebroventricularly with streptozotocin (STZ; 3 mg/kg) twice, on day 1 and 3, to induce AD-like condition, and the symptoms were evaluated after 14 days. While the loss of learning and memory performance was evident in the mice subjected to Morris water maze (MWM), there was a striking increase in the population of astrocytes labelled with glial fibrillary acidic protein (GFAP) in the hippocampus. Daily intraperitoneal (i.p.) treatment with plumbagin (0.5 and 1 mg/kg), starting from 1 h prior to first dose of STZ, significantly prevented the cognitive deficits in MWM. On the other hand, administration of Nrf2/ARE pathway inhibitor, trigonelline (10 and 15 mg/kg, i.p.) enhanced the effects of STZ. Pre-treatment with subeffective dose of trigonelline (5 mg/kg) significantly attenuated the effects of plumbagin in MWM. While plumbagin prevented the STZ induced GFAP expression, this effect of plumbagin was attenuated by trigonelline. Moreover, the in silico docking study revealed potent inhibitory effect of plumbagin on β-secretase enzyme. The results of the present study suggest that plumbagin improves cognitive function in STZ induced mouse model of AD possibly via Nrf2/ARE mediated suppression of astrogliosis and inhibition of β-secretase enzyme.

Topics: Alzheimer Disease; Amyloid Precursor Protein Secretases; Animals; Antioxidant Response Elements; Cerebral Cortex; Cognition Disorders; Cognitive Dysfunction; Disease Models, Animal; Hippocampus; Male; Maze Learning; Memory; Mice; Naphthoquinones; Neuroprotective Agents; NF-E2-Related Factor 2; Oxidative Stress; Streptozocin

Plumbagin, a vitamin K3 analogue is the major active constituent in several plants including root of Plumbago indica Linn. This compound has been shown to exhibit a wide spectrum of pharmacological activities. The present investigation was to evaluate the ameliorative effects of plumbagin (PL) against severe malaria pathogenesis due to involvement of oxidative stress and inflammatory response in Plasmodium berghei infected malaria in mice. Malaria pathogenesis was induced by intra-peritoneal injection of P. berghei infected red blood cells into the Swiss albino mice. PL was administered orally at doses of 3, 10 and 30 mg/kg/day following Peter's 4 day suppression test. Oral administration of PL showed significant reduction of parasitaemia and increase in mean survival time. PL treatment is also attributed to significant increase in the blood glucose and haemoglobin level when compared with vehicle-treated infected mice. Significant inhibition in level of oxidative stress and pro-inflammation related markers were observed in PL treated group. The trend of inhibition in oxidative stress markers level after oral treatment of PL was MPO > LPO > ROS in organ injury in P. berghei infected mice. This study showed that plumbagin is able to ameliorate malaria pathogenesis by augmenting anti-oxidative and anti-inflammatory mechanism apart from its effect on reducing parasitaemia and increasing mean survival time of malaria-induced mice.

Topics: Administration, Oral; Animals; Anti-Inflammatory Agents; Antimalarials; Disease Models, Animal; Dose-Response Relationship, Drug; Inflammation; Malaria; Male; Mice; Naphthoquinones; Oxidative Stress; Plasmodium berghei; Plumbaginaceae

Nanoenabled lipid-based drug delivery systems offer a platform to overcome challenges encountered with current failed leads in the treatment of parasitic and infectious diseases. When prepared with FDA or EMA approved excipients, they can be readily translated without the need for further toxicological studies, while they remain affordable and amenable to scale-up. Buparvaquone (BPQ), a hydroxynapthoquinone with in vitro activity in the nanomolar range, failed to clinically translate as a viable treatment for visceral leishmaniasis due to its poor oral bioavailability limited by its poor aqueous solubility (BCS Class II drug). Here we describe a self-nanoemulsifying system (SNEDDS) with high loading and thermal stability up to 6 months in tropical conditions and the ability to enhance the solubilization capacity of BPQ in gastrointestinal media as demonstrated by flow-through cell and dynamic in vitro lipolysis studies. BPQ SNEDDS demonstrated an enhanced oral bioavailability compared to aqueous BPQ dispersions (probe-sonicated), resulting in an increased plasma AUC

Topics: Administration, Oral; Animals; Antiprotozoal Agents; Biological Availability; Cell Line; Disease Models, Animal; Drug Carriers; Drug Compounding; Drug Liberation; Drug Stability; Emulsions; Excipients; Feasibility Studies; Humans; Leishmania infantum; Leishmaniasis, Visceral; Lipids; Male; Mice; Mice, Inbred BALB C; Nanoparticles; Naphthoquinones; Solubility; Treatment Outcome

Ischemia-reperfusion (I/R) injury is a pathological process which magnifies with the ensuing inflammatory response and endures with the increase of oxidants especially during reperfusion. The present study was conducted to assess the possible modulatory effects of plumbagin, the active constituent extracted from the roots of traditional medicinal plant Plumbago zeylanica L., on the dire role of high mobility group box 1 (HMGB1) as well as the associated inflammation, oxidative stress and apoptotic cell death following hepatic I/R. Four groups of rats were included: sham-operated, sham-operated treated with plumbagin, I/R (30 min ischemia and 1 h reperfusion) and I/R treated with plumbagin. Pretreatment with plumbagin markedly improved hepatic function and structural integrity compared to the I/R group, as manifested by depressed plasma transaminases and lactate dehydrogenase (LDH) activities as well as alleviated tissue pathological lesions. Plumbagin prominently hampered HMGB1 expression and subsequently quelled inflammatory cascades, as nuclear factor κB (NF-κB), tumor necrosis factor-alpha (TNF-α) and myeloperoxidase (MPO) activity. It also interrupted reactive oxygen species (ROS)-HMGB1loop as evident by restored liver reduced glutathione (GSH), elevated glutathione peroxidase (GPx) activity, along with decreased liver lipid peroxidation. Simultaneously, plumbagin significantly ameliorated apoptosis by amending the mRNA expressions of both anti-apoptotic (Bcl-2) and pro-apoptotic (Bax). The present results revealed that plumbagin is endowed with hepatoprotective activity ascribed to its antioxidant, anti-inflammatory and anti-apoptotic properties which are partially mediated through dampening of HMGB1 expression.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Apoptosis; Biomarkers; Cytoprotection; Disease Models, Animal; Enzymes; Glutathione; Glutathione Peroxidase; Hepatitis; HMGB1 Protein; Inflammation Mediators; Lipid Peroxidation; Liver; Male; Naphthoquinones; Oxidative Stress; Rats, Wistar; Reactive Oxygen Species; Reperfusion Injury; Signal Transduction

The effects of therapeutic or preventive-therapeutic administration of water-soluble echinochrome analog U-441 on arrhythmia severity assessed by a set of myocardial spatio-temporal depolarization and repolarization parameters were examined on the model of acute myocardial ischemia in cats. Coronary occlusion increased activation time and decreased repolarization time in the ischemic zone; in addition, it increased both global and borderline (local) dispersions of repolarization. The linear regression model showed that only activation time values measured at the initial state and at termination of occlusion were associated with total arrhythmia score during ischemia (regression coefficient β=0.338, 95%CI=0.074-0.602, p=0.015 and β=0.720, 95%CI=0.323-1.117, p=0.001, respectively). The study revealed no association between administration of echinochrome analog U-441 and arrhythmia severity.

Topics: Animals; Anti-Arrhythmia Agents; Arrhythmias, Cardiac; Cats; Coronary Occlusion; Disease Models, Animal; Electrocardiography; Heart Conduction System; Myocardial Ischemia; Myocardium; Naphthoquinones; Sea Urchins; Severity of Illness Index; Solubility; Treatment Failure; Water

Gain-of-function mutations in fibroblast growth factor receptors (FGFRs) cause congenital skeletal anomalies, including craniosynostosis (CS), which is characterized by the premature closure of craniofacial sutures. Apert syndrome (AS) is one of the severest forms of CS, and the only treatment is surgical expansion of prematurely fused sutures in infants. Previously, we demonstrated that the prolyl isomerase peptidyl-prolyl cis-trans isomerase interacting 1 (PIN1) plays a critical role in mediating FGFR signaling and that Pin1+/- mice exhibit delayed closure of cranial sutures. In this study, using both genetic and pharmacological approaches, we tested whether PIN1 modulation could be used as a therapeutic regimen against AS. In the genetic approach, we crossbred Fgfr2S252W/+, a mouse model of AS, and Pin1+/- mice. Downregulation of Pin1 gene dosage attenuated premature cranial suture closure and other phenotypes of AS in Fgfr2S252W/+ mutant mice. In the pharmacological approach, we intraperitoneally administered juglone, a PIN1 enzyme inhibitor, to pregnant Fgfr2S252W/+ mutant mice and found that this treatment successfully interrupted fetal development of AS phenotypes. Primary cultured osteoblasts from Fgfr2S252W/+ mutant mice expressed high levels of FGFR2 downstream target genes, but this phenotype was attenuated by PIN1 inhibition. Post-translational stabilization and activation of Runt-related transcription factor 2 (RUNX2) in Fgfr2S252W/+ osteoblasts were also attenuated by PIN1 inhibition. Based on these observations, we conclude that PIN1 enzyme activity is important for FGFR2-induced RUNX2 activation and craniofacial suture morphogenesis. Moreover, these findings highlight that juglone or other PIN1 inhibitors represent viable alternatives to surgical intervention for treatment of CS and other hyperostotic diseases.

Topics: Acrocephalosyndactylia; Animals; Core Binding Factor Alpha 1 Subunit; Cranial Sutures; Craniosynostoses; Disease Models, Animal; Female; Gain of Function Mutation; Gene Expression Regulation; Humans; Mice; Morphogenesis; Naphthoquinones; NIMA-Interacting Peptidylprolyl Isomerase; Osteoblasts; Pregnancy; Primary Cell Culture; Receptor, Fibroblast Growth Factor, Type 2; Signal Transduction

Shiunko ointment is composed of five ingredients including Lithospermi Radix (LR), Angelicae Gigantis Radix, sesame seed oil, beeswax, and swine oil. It is externally applied as a treatment for a wide range of skin conditions such as eczema, psoriasis, hair loss, burns, topical wounds, and atopic dermatitis. Deoxyshikonin is the major angiogenic compound extracted from LR. In this study, we investigated the efficacy of LR extract and deoxyshikonin on impaired wound healing in streptozotocin (STZ)-induced diabetic mice. Treatment with LR extract elevated tube formation in human umbilical vein endothelial cells (HUVECs) and exerted antioxidant activity. An open skin wound was produced on the backs of diabetic mice and was then topically treated with deoxyshikonin or vehicle. In addition, deoxyshikonin promoted tube formation in high glucose conditions exposed to HUVECs, and which may be regulated by increased VEGFR2 expression and phosphorylation of Akt and p38. Our results demonstrate that deoxyshikonin application promoted wound repair in STZ-induced diabetic mice. Collectively, these data suggest that deoxyshikonin is an active ingredient of LR, thereby contributing to wound healing in patients with diabetes.

Topics: Animals; Cell Proliferation; Diabetes Mellitus, Experimental; Disease Models, Animal; Extracellular Signal-Regulated MAP Kinases; Human Umbilical Vein Endothelial Cells; Humans; Lithospermum; Male; Mice; Mice, Inbred ICR; Naphthoquinones; Neovascularization, Physiologic; Oxidative Stress; p38 Mitogen-Activated Protein Kinases; Plant Extracts; RNA, Messenger; Vascular Endothelial Growth Factor A; Vascular Endothelial Growth Factor Receptor-2; Wound Healing

Establishment of a mouse model for congenital toxoplasmosis based on oral infection with oocysts from Toxoplasma gondii ME49 and its application for investigating chemotherapeutic options against congenital toxoplasmosis.. CD1 mice were mated, orally infected with 5, 25, 100, 500 or 2000 oocysts and monitored for clinical signs and survival of dams and pups until 4 weeks post partum . The parasite burden in infected mice was quantified by real-time PCR in lungs, brains and, in the case of surviving pups, also in eyes. Seroconversion was assessed by ELISA. T. gondii cysts in brain were identified by immunofluorescence. In a second experiment, pregnant CD1 mice challenged with 20 oocysts/mouse were treated with buparvaquone or the calcium-dependent protein kinase 1 inhibitor bumped kinase inhibitor (BKI)-1294 and the outcome of infection was analysed.. T. gondii DNA was detected in the brain of all infected animals, irrespective of the infection dose. Seroconversion occurred at 3 weeks post-infection. Most pups born to infected dams died within 1 week post partum , but a small fraction survived until the end of the experiment. T. gondii DNA was detected in the brain of all survivors and half of them exhibited ocular infection. Chemotherapy with both compounds led to dramatically increased numbers of surviving pups and reduced cerebral infection. Most efficient were treatments with BKI-1294, with 100% survivors and only 7% brain-positive pups.. BKI-1294 and buparvaquone exert excellent activities against transplacental transmission in pregnant mice.

Topics: Animals; Antiprotozoal Agents; Disease Models, Animal; Female; Infectious Disease Transmission, Vertical; Male; Mice; Naphthalenes; Naphthoquinones; Piperidines; Pyrazoles; Toxoplasmosis, Animal; Toxoplasmosis, Congenital; Treatment Outcome

NQO1 is a FAD-binding protein that can form homodimers and reduce quinones to hydroquinones, and a growing body of evidence currently suggests that NQO1 is dramatically elevated in solid cancers. Here, we demonstrated that NQO1 was elevated in breast cancer and that its expression level was positively correlated with invasion and reduced disease free survival (DFS) and overall survival (OS) rates. Next, we found that β-lapachone exerted significant anti-proliferation and anti-metastasis effects in breast cancer cell lines due to its effects on NQO1 expression. Moreover, we revealed that the anti-cancer effects of β-lapachone were mediated by the inactivation of the Akt/mTOR pathway. In conclusion, these results demonstrated that NQO1 could be a useful prognostic biomarker for patients with breast cancer, and its bioactivatable drug, β-lapachone represented a promising new development and an effective strategy for indicating the progression of NQO1-positive breast cancers.

Topics: Animals; Biomarkers, Tumor; Breast Neoplasms; Cell Line, Tumor; Cell Movement; Cell Proliferation; Disease Models, Animal; Disease Progression; Dose-Response Relationship, Drug; Epithelial-Mesenchymal Transition; Female; Gene Expression; Humans; Mice; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Neoplasm Grading; Neoplasm Staging; Prognosis; Xenograft Model Antitumor Assays

Fusarium oxysporum is an ascomycete facultative fungus which generally affects to plants. However, it is recently known as a serious emerging opportunistic pathogen of human and other animals. F. oxysporum shows broad resistance to commonly used antifungal agents and therefore development of alternative therapeutic agents is required. In this study, we investigated the antifungal efficacy of plant based natural lawsone against pathogenic F. oxysporum. Antifungal susceptibility test determined the concentration dependent growth inhibition of lawsone against F. oxysporum with minimum inhibitory concentration (MIC) at 100μg/mL. Ultra-structural analysis indicates the prominent damage on cell wall of the mycelium after lawsone treatment, and suggests that it could increase the membrane permeability and disintegration of cells leading to cellular death. Propidium iodide (PI) uptake assay results showed the higher level of cell death in lawsone treated F. oxysporum which further confirms the loss of plasma membrane integrity. Also, detection of reactive oxygen species (ROS) using DCFH-DA has clearly indicated that lawsone (100μg/mL) can induce the ROS level in the filaments of F. oxysporum. MTT assay results showed the loss of viability and germination capacity of F. oxysporum spores by lawsone in concentration dependent manner. Moreover, lawsone treatment induced the mRNA expression of two autophagy related genes (ATG1 and ATG8) indicating that lawsone may activate the autophagy related pathways in F. oxysporum due to the oxidative stress generated by ROS. F. oxysporum infected zebrafish has recovered after lawsone therapy as a topical treatment suggesting that lawsone is a potential natural antifusariosis agent.

Topics: Animals; Antifungal Agents; Autophagy; Cell Membrane; Cell Membrane Permeability; Cell Wall; Disease Models, Animal; Fish Diseases; Fluoresceins; Fusarium; Gene Expression Regulation, Fungal; Genes, Fungal; Hyphae; In Vitro Techniques; Microbial Sensitivity Tests; Microbial Viability; Microscopy, Confocal; Microscopy, Electron, Scanning; Muscles; Naphthoquinones; Pest Control, Biological; Plant Diseases; Plant Extracts; Propidium; Reactive Oxygen Species; RNA, Messenger; Spores, Fungal; Zebrafish

Follicular thyroid carcinoma's (FTC) overall good prognosis deteriorates if the tumour fails to retain radioactive iodine. Therefore, new druggable targets are in high demand for this subset of patients. Here, we investigated the prognostic and biological role of survivin and XIAP in FTC. Survivin and XIAP expression was investigated in 44 FTC and corresponding non-neoplastic thyroid specimens using tissue microarrays. Inhibition of both inhibitor of apoptosis proteins (IAP) was induced by shRNAs or specific small molecule antagonists and functional changes were investigated in vitro and in vivo. Survivin and XIAP were solely expressed in FTC tissue. Survivin expression correlated with an advanced tumour stage and recurrent disease. In addition, survivin proved to be an independent negative prognostic marker. Survivin or XIAP knockdown caused a significant reduction in cell viability and proliferation, activated caspase3/7 and was associated with a reduced tumour growth in vivo. IAP-targeting compounds induced a decrease of cell viability, proliferation and cell cycle activity accompanied by an increase in apoptosis. Additionally, YM155 a small molecule inhibitor of survivin expression significantly inhibited tumour growth in vivo. Both IAPs demonstrate significant functional implications in the oncogenesis of FTCs and thus prove to be viable targets in patients with advanced FTC.

Topics: Adenocarcinoma, Follicular; Animals; Biomarkers, Tumor; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Female; Gene Expression; Gene Knockout Techniques; Humans; Imidazoles; Immunohistochemistry; Male; Mice; Naphthoquinones; Neoplasm Staging; Prognosis; Survivin; Thyroid Neoplasms; X-Linked Inhibitor of Apoptosis Protein; Xenograft Model Antitumor Assays

Human Chronic Myelogenous Leukemia (CML) is a hematological stem cell disorder which is associated with activation of Bcr-Abl-Stat5 oncogenic pathway. Direct Bcr-Abl inhibitors are initially successful for the treatment of CML but over time many patients develop drug resistance. In the present study, the effects of CM363, a novel naphthoquinone (NPQ) derivative, were evaluated on human CML-derived K562 cells. CM363 revealed an effective cell growth inhibition (IC50 = 0.7 ± 0.5 μM) by inducing cancer cells to undergo cell cycle arrest and apoptosis. CM363 caused a dose- and time-dependent reduction of cells in G0/G1 and G2/M phases. This cell cycle arrest was associated with increased levels of cyclin E, pChk1 and pChk2 whereas CM363 downregulated cyclin B, cyclin D3, p27, pRB, Wee1, and BUBR1. CM363 increased the double-strand DNA break marker γH2AX. CM363 caused a time-dependent increase of annexin V-positive cells, DNA fragmentation and increased number of apoptotic nuclei. CM363 triggered the mitochondrial apoptotic pathway as reflected by a release of cytochrome C from mitochondria and induction of the cleavage of caspase-3 and -9, and PARP. CM363 showed multikinase modulatory effects through an early increased JNK phosphorylation followed by inhibition of pY-Bcrl-Abl and pY-Stat5. CM363 worked synergistically with imatinib to inhibit cell viability and maintained its activity in imatinib-resistant cells. Finally, CM363 (10 mg/Kg) suppressed the growth of K562 xenograft tumors in athymic mice. In summary, CM363 is a novel multikinase modulator that offers advantages to circumvent imanitib resistance and might be therapeutically effective in Bcrl-Abl-Stat5 related malignancies.

Topics: Animals; Antineoplastic Agents; Apoptosis; Cell Cycle; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Drug Resistance, Neoplasm; Female; Fusion Proteins, bcr-abl; Humans; Imatinib Mesylate; JNK Mitogen-Activated Protein Kinases; K562 Cells; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Mice; Naphthoquinones; Protein Kinase Inhibitors; Signal Transduction; STAT5 Transcription Factor; Xenograft Model Antitumor Assays

Deregulation of glutamate homeostasis is associated with degenerative neurological disorders. Glutamate dehydrogenase (GDH) is important for glutamate metabolism and plays a central role in expanding the pool of tricarboxylic acid (TCA) cycle intermediate alpha-ketoglutarate (α-KG), which improves overall bioenergetics. Under high energy demand, maintenance of ATP production results in functionally active mitochondria. Here, we tested whether the modulation of GDH activity can rescue ischemia/reperfusion-induced neuronal death in an in vivo mouse model of middle artery occlusion and an in vitro oxygen/glucose depletion model. Iodoacetate, an inhibitor of glycolysis, was also used in a model of energy failure, remarkably depleting ATP and α-KG. To stimulate GDH activity, the GDH activator 2-aminobicyclo-(2,2,1)-heptane-2-carboxylic acid and potential activator beta-lapachone were used. The GDH activators restored α-KG and ATP levels in the injury models and provided potent neuroprotection. We also found that beta-lapachone increased glutamate utilization, accompanied by a reduction in extracellular glutamate. Thus, our hypothesis that mitochondrial GDH activators increase α-KG production as an alternative energy source for use in the TCA cycle under energy-depleted conditions was confirmed. Our results suggest that increasing GDH-mediated glutamate oxidation represents a new therapeutic intervention for neurodegenerative disorders, including stoke.

Topics: Animals; Astrocytes; Brain; Brain Ischemia; Cell Death; Cells, Cultured; Coculture Techniques; Disease Models, Animal; Glutamate Dehydrogenase; Infarction, Middle Cerebral Artery; Male; Mice, Inbred ICR; Mitochondria; Naphthoquinones; Neurons; Neuroprotective Agents; Random Allocation; Reperfusion Injury

Using multiple drugs to kill cancer cells can decrease drug resistance development. However, this approach is frequently limited by the bioavailability and toxicity of the combined agents and delivery at ratios to specific locations that synergistically kill cancer cells. Loading the individual agents into a nanoparticle that releases the drugs at synergizing ratios at a single location is one approach to resolve this concern. Celecoxib and plumbagin are two drugs that were identified from a screen to synergistically kill melanoma cells compared with normal cells. Combined use of these agents by traditional approaches was not possible due to poor bioavailability and toxicologic concerns. This study details the development of a nanoliposomal-based agent containing celecoxib and plumbagin, called CelePlum-777, which is stable and releases these drugs at an optimal ratio for maximal synergistic killing efficacy. CelePlum-777 was more effective at killing melanoma than normal cells and inhibited xenograft melanoma tumor growth by up to 72% without apparent toxicity. Mechanistically, the drug combination in CelePlum-777 led to enhanced inhibition of melanoma cell proliferation mediated by decreasing levels of key cyclins important for cancer cell proliferation and survival, which was not observed with the individual agents. Thus, a novel nanoparticle-based drug has been developed containing celecoxib and plumbagin that lacks toxicity and delivers the agents at a synergistically killing drug ratio to kill cancer cells.

Topics: Animals; Antineoplastic Agents, Phytogenic; Celecoxib; Cell Line, Tumor; Cell Survival; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; Drug Compounding; Drug Stability; Drug Synergism; Female; Humans; Liposomes; Melanoma; Mice; Nanoparticles; Naphthoquinones; STAT3 Transcription Factor; Tumor Burden; Xenograft Model Antitumor Assays

Shikonin has been reported to induce glioma cell death via necroptosis, a type of programmed necrosis primarily mediated by RIP1 and RIP3. Although RIP1 and RIP3 are found to regulate some features of necrosis such as energy depletion and cellular membrane disruption, it remains unclear whether RIP1 and RIP3 could modulate DNA double strand breaks (DSBs), which is a crucial event leading to chromatinolysis. In this study, we used glioma cell lines and mice model of xenograft glioma to investigate the roles of RIP1 and RIP3 in shikonin-induced DNA DSBs. We found that shikonin induced upregulation of RIP1 and RIP3, necrosome formation and DNA DSBs in vitro and in vivo. In vitro investigation showed that the DNA DSBs and the reduction of cellular viabilities induced by shikonin were both prevented when RIP1 or RIP3 was pharmacologically inhibited by specific inhibitor or genetically knocked down with siRNA. Then, we proved that suppression of intracellular ROS with antioxidant NAC inhibited DNA DSBs caused by either hydrogen peroxide or shikonin, suggesting that ROS played a crucial role in regulation of DNA DSBs of glioma cells induced by shikonin. Further, we found that RIP1 and RIP3 regulated shikonin-induced overproduction of ROS via causing excessive generation of mitochondrial superoxide and depletion of GSH, indicating that ROS was the downstream signal of RIP1 and RIP3. Taken together, we demonstrated that RIP1 and RIP3 contributed to shikonin-induced DNA DSBs in glioma cells via increase of intracellular ROS levels.

Topics: Animals; Cell Line, Tumor; Disease Models, Animal; DNA Breaks, Double-Stranded; Glioma; Heterografts; Mice; Naphthoquinones; Nuclear Pore Complex Proteins; Reactive Oxygen Species; Receptor-Interacting Protein Serine-Threonine Kinases; RNA-Binding Proteins; Up-Regulation

Chronic kidney diseases generally lead to renal fibrosis. Despite great progress having been made in identifying molecular mediators of fibrosis, the mechanism that governs renal fibrosis remains unclear, and so far no effective therapeutic antifibrosis strategy is available. Here we demonstrated that a switch of metabolism from oxidative phosphorylation to aerobic glycolysis (Warburg effect) in renal fibroblasts was the primary feature of fibroblast activation during renal fibrosis and that suppressing renal fibroblast aerobic glycolysis could significantly reduce renal fibrosis. Both gene and protein assay showed that the expression of glycolysis enzymes was upregulated in mouse kidneys with unilateral ureter obstruction (UUO) surgery or in transforming growth factor-β1 (TGF-β1)-treated renal interstitial fibroblasts. Aerobic glycolysis flux, indicated by glucose uptake and lactate production, was increased in mouse kidney with UUO nephropathy or TGF-β1-treated renal interstitial fibroblasts and positively correlated with fibrosis process. In line with this, we found that increasing aerobic glycolysis can remarkably induce myofibroblast activation while aerobic glycolysis inhibitors shikonin and 2-deoxyglucose attenuate UUO-induced mouse renal fibrosis and TGF-β1-stimulated myofibroblast activation. Furthermore, mechanistic study indicated that shikonin inhibits renal aerobic glycolysis via reducing phosphorylation of pyruvate kinase type M2, a rate-limiting glycolytic enzyme associated with cell reliance on aerobic glycolysis. In conclusion, our findings demonstrate the critical role of aerobic glycolysis in renal fibrosis and support treatment with aerobic glycolysis inhibitors as a potential antifibrotic strategy.

Topics: Animals; Carrier Proteins; Cell Line; Deoxyglucose; Disease Models, Animal; Fibrosis; Glycolysis; Kidney; Male; Membrane Proteins; Mice; Myofibroblasts; Naphthoquinones; Phosphorylation; Pyruvate Kinase; Rats; Renal Insufficiency, Chronic; Thyroid Hormone-Binding Proteins; Thyroid Hormones; Time Factors; Transforming Growth Factor beta1; Ureteral Obstruction

Ototoxicity is an important issue in patients receiving cisplatin chemotherapy. Numerous studies have demonstrated that cisplatin-induced ototoxicity is related to oxidative stress and DNA damage. However, the precise mechanism underlying cisplatin-associated ototoxicity is still unclear. The cofactor nicotinamide adenine dinucleotide (NAD(+)) has emerged as an important regulator of energy metabolism and cellular homeostasis. Here, we demonstrate that the levels and activities of sirtuin-1 (SIRT1) are suppressed by the reduction of intracellular NAD(+) levels in cisplatin-mediated ototoxicity. We provide evidence that the decreases in SIRT1 activity and expression facilitated by increasing poly(ADP-ribose) polymerase-1 (PARP-1) activation and microRNA-34a levels through cisplatin-mediated p53 activation aggravate the associated ototoxicity. Furthermore, we show that the induction of cellular NAD(+) levels using dunnione, which targets intracellular NQO1, prevents the toxic effects of cisplatin through the regulation of PARP-1 and SIRT1 activity. These results suggest that direct modulation of cellular NAD(+) levels by pharmacological agents could be a promising therapeutic approach for protection from cisplatin-induced ototoxicity.

Topics: Acetylation; Animals; Cisplatin; Cochlea; Cytoprotection; Disease Models, Animal; Hearing; Hearing Loss; Male; Mice, Inbred C57BL; Mice, Knockout; MicroRNAs; NAD; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Poly (ADP-Ribose) Polymerase-1; Protective Agents; Signal Transduction; Sirtuin 1; Transcription Factor RelA; Tumor Necrosis Factor-alpha; Tumor Suppressor Protein p53

Tauopathies, such as Alzheimer's disease (AD), are a group of disorders characterized neuropathologically by intracellular toxic accumulations of abnormal protein aggregates formed by misfolding of the microtubule-associated protein tau. Since protein self-assembly appears to be an initial key step in the pathology of this group of diseases, intervening in this process can be both a prophylactic measure and a means for modifying the course of the disease for therapeutic purposes. We and others have shown that aromatic small molecules can be effective inhibitors of aggregation of various protein assemblies, by binding to the aromatic core in aggregation-prone motifs and preventing their self-assembly. Specifically, we have designed a series of small aromatic naphthoquinone-tryptophan hybrid molecules as candidate aggregation inhibitors of β -sheet based assembly and demonstrated their efficacy toward inhibiting aggregation of the amyloid-β peptide, another culprit of AD, as well as of various other aggregative proteins involved in other protein misfolding diseases. Here we tested whether a leading naphthoquinone-tryptophan hybrid molecule, namely NQTrp, can be repurposed as an inhibitor of the aggregation of the tau protein in vitro and in vivo. We show that the molecule inhibits the in vitro assembly of PHF6, the aggregation-prone fragment of tau protein, reduces hyperphosphorylated tau deposits and ameliorates tauopathy-related behavioral defect in an established transgenic Drosophila model expressing human tau. We suggest that NQTrp, or optimized versions of it, could act as novel disease modifying drugs for AD and other tauopathies.

Topics: Animals; Carrier Proteins; Disease Models, Animal; Drosophila; Drosophila Proteins; Eye; Female; Humans; Immunoprecipitation; In Vitro Techniques; Larva; Locomotion; Mice, Transgenic; Microscopy, Electron, Scanning; Naphthoquinones; Neurotoxicity Syndromes; Oligopeptides; Protein Aggregates; Retinal Pigments; tau Proteins; Tryptophan

Amyloid-β, one of the hallmarks of Alzheimer's disease, is toxic to neurons and causes cell death in the brain. Oxidative stress is known to play an important role in Alzheimer's disease, and there is strong evidence linking oxidative stress to amyloid-β. The herbal plant "Tiew kon" (Cratoxylum formosum ssp. pruniflorum) is an indigenous vegetable that is grown in Southeast Asia. Many reports suggested that the twig extract from C. formosum possesses an antioxidant property. The purpose of this study was to investigate the protective effect of the twig extract from C. formosum against amyloid-β toxicity using the transgenic Caenorhabditis elegans model. This study demonstrated that the extract significantly delayed amyloid-β-induced paralysis in the C. elegans model of Alzheimer's disease. Using a genetic approach, we found that DAF-16/FOXO transcription factor, heat shock factor 1, and SKN-1 (Nrf2 in mammals) were required for the extract-mediated delayed paralysis. The extract ameliorated oxidative stress by reducing the level of H2O2, which appeared to account for the protective action of the extract. The extract possesses antioxidant activity against juglone-induced oxidative stress as it was shown to increase survival of the stressed worms. In addition, C. formosum decreased the expression of the heat shock protein-16.2 gene which was induced by thermal stress, indicating its ability to reduce cellular stress. The results from this study support the C. elegans model in the search for disease-modifying agents to treat Alzheimer's disease and indicate the potential of the extract from C. formosum ssp. pruniflorum as a source for the development of anti-Alzheimer's drugs.

Topics: Alzheimer Disease; Amyloid beta-Peptides; Animals; Animals, Genetically Modified; Antioxidants; Caenorhabditis elegans; Caenorhabditis elegans Proteins; Clusiaceae; Disease Models, Animal; DNA-Binding Proteins; Forkhead Transcription Factors; Naphthoquinones; Oxidative Stress; Paralysis; Plant Extracts; Protective Agents; Transcription Factors

The treatment of breast cancer-induced osteolysis remains a challenge in clinical settings. Here, we explored the effect and mechanism of combined treatment with zoledronic acid (ZA) and plumbagin (PL), a widely investigated component derived from Plumbago zeylanica, against breast cancer-induced osteoclastogenesis. We found that the combined treatment with PL and ZA suppressed cell viability of precursor osteoclasts and synergistically inhibited MDA-MB-231-induced osteoclast formation (combination index=0.28) with the abrogation of recombinant mouse receptor activator of nuclear factor-κB ligand (RANKL)-induced activation of NF-κB/MAPK (nuclear factor-κB/mitogen-activated protein kinase) pathways. Molecular docking suggested a putative binding area within c-Jun N-terminal kinase/extracellular signal-regulated kinase (JNK/Erk) protease active sites through the structural mimicking of adenosine phosphate (ANP) by the spatial combination of PL with ZA. A homogeneous time-resolved fluorescence assay further illustrated the direct competitiveness of the dual drugs against ANP docking to phosphorylated JNK/Erk, contributing to the inhibited downstream expression of c-Jun/c-Fos/NFATc-1 (nuclear factor of activated T cells, cytoplasmic, calcineurin-dependent 1). Then, in vivo testing demonstrated that the combined administration of PL and ZA attenuated breast cancer growth in the bone microenvironment. Additionally, these molecules prevented the destruction of proximal tibia, with significant reduction of tartrate-resistant acid phosphatase (TRAcP)-positive osteoclast cells and potentiation of apoptotic cancer cells, to a greater extent when combined than when the drugs were applied independently. Altogether, the combination treatment with PL and ZA could significantly and synergistically suppress osteoclastogenesis and inhibit tumorigenesis both in vitro and in vivo by simulating the spatial structure of ANP to inhibit competitively phosphorylation of c-Jun N-terminal kinase/extracellular signal-regulated kinase (JNK/Erk).

Topics: Adenine Nucleotides; Animals; Antineoplastic Combined Chemotherapy Protocols; Breast Neoplasms; Cell Line, Tumor; Diphosphonates; Disease Models, Animal; Drug Synergism; Female; Humans; Imidazoles; JNK Mitogen-Activated Protein Kinases; MAP Kinase Signaling System; Mice; Mice, Inbred BALB C; Mice, Nude; Naphthoquinones; Osteoclasts; Osteolysis; Phosphorylation; Random Allocation; Signal Transduction; Zoledronic Acid

Two chromone C-glucosides, biflorin (1) and isobiflorin (2), were isolated from the flower buds of Syzygium aromaticum L. (Myrtaceae). Here, inhibitory effects of 1 and 2 on lipopolysaccharide (LPS)-induced production of nitric oxide (NO) and prostaglandin E2 (PGE2) in RAW 264.7 macrophages were evaluated, and 1 (IC50 = 51.7 and 37.1 μM, respectively) was more potent than 2 (IC50 > 60 and 46.0 μM). The suppression of NO and PGE2 production by 1 correlated with inhibition of iNOS and COX-2 protein expression. Compound 1 reduced inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) mRNA expression via inhibition of their promoter activities. Compound 1 inhibited the LPS-induced production and mRNA expression of tumor necrosis factor-α (TNF-α) and interleukin (IL)-6. Furthermore, 1 reduced p-STAT1 and p-p38 expression but did not affect the activity of nuclear factor κ light-chain enhancer of activated B cells (NF-κB) or activator protein 1 (AP-1). In a mouse model of LPS-induced endotoxemia, 1 reduced the mRNA levels of iNOS, COX-2, and TNF-α, and the phosphorylation-mediated activation of the signal transducer and activator of transcription 1 (STAT1), consequently improving the survival rates of mice. Compound 1 showed a significant anti-inflammatory effect on carrageenan-induced paw edema and croton-oil-induced ear edema in rats. The collective data indicate that the suppression of pro-inflammatory gene expression via p38 mitogen-activated protein kinase and STAT1 inactivation may be a mechanism for the anti-inflammatory activity of 1.

Topics: Animals; Anti-Inflammatory Agents; Carrageenan; Cyclooxygenase 2; Dinoprostone; Disease Models, Animal; Edema; Endotoxemia; Flowers; Inflammation Mediators; Interleukin-6; Lipopolysaccharides; Macrophages; Male; Mice; Molecular Structure; Naphthoquinones; NF-kappa B; Nitric Oxide; p38 Mitogen-Activated Protein Kinases; Rats; STAT1 Transcription Factor; Syzygium; Transcription Factor AP-1; Tumor Necrosis Factor-alpha

Visceral leishmaniasis (VL) is the most severe form of leishmaniasis and is the second major cause of death by parasites, after malaria. The arsenal of drugs against leishmaniasis is small, and each has a disadvantage in terms of toxicity, efficacy, price, or treatment regimen. Our group has focused on studying new drug candidates as alternatives to current treatments. The pterocarpanquinone LQB-118 was designed and synthesized based on molecular hybridization, and it exhibited antiprotozoal and anti-leukemic cell line activities. Our previous work demonstrated that LQB-118 was an effective treatment for experimental cutaneous leishmaniasis. In this study, we observed that treatment with 10 mg/kg of body weight/day LQB-118 orally inhibited the development of hepatosplenomegaly with a 99% reduction in parasite load. An in vivo toxicological analysis showed no change in the clinical, biochemical, or hematological parameters. Histologically, all of the analyzed organs were normal, with the exception of the liver, where focal points of necrosis with leukocytic infiltration were observed at treatment doses 5 times higher than the therapeutic dose; however, these changes were not accompanied by an increase in transaminases. Our findings indicate that LQB-118 is effective at treating different clinical forms of leishmaniasis and presents no relevant signs of toxicity at therapeutic doses; thus, this framework is demonstrated suitable for developing promising drug candidates for the oral treatment of leishmaniasis.

Topics: Animals; Antiprotozoal Agents; Disease Models, Animal; Drug Evaluation, Preclinical; Female; Gastric Absorption; Hepatomegaly; Humans; Inhibitory Concentration 50; Intubation, Gastrointestinal; Leishmania infantum; Leishmaniasis, Visceral; Mice; Mice, Inbred BALB C; Naphthoquinones; Organ Specificity; Parasitemia; Pterocarpans; Splenomegaly; Toxicity Tests, Subacute

Autophagy, a lysosome-mediated self-degradation process of eukaryotic cells, serves as a main route for the elimination of cellular damage [1-3]. Such damages include aggregated, oxidized or misfolded proteins whose accumulation can cause various neurodegenerative pathologies, including Huntington's disease (HD).. Here we examined whether enhanced autophagic activity can alleviate neurophatological features in a Drosophila model of HD (the transgenic animals express a human mutant Huntingtin protein with a long polyglutamine repeat, 128Q).. We have recently identified an autophagy-enhancing small molecule, AUTEN-67 (autophagy enhancer 67), with potent neuroprotective effects [4]. AUTEN-67 was applied to induce autophagic activity in the HD model used in this study.. We showed that AUTEN-67 treatment interferes with the progressive accumulation of ubiquitinated proteins in the brain of Drosophila transgenic for the pathological 128Q form of human Huntingtin protein. The compound significantly improved the climbing ability and moderately extended the mean life span of these flies. Furthermore, brain tissue samples from human patients diagnosed for HD displayed increased levels of the autophagy substrate SQSTM1/p62 protein, as compared with controls.. These results imply that AUTEN-67 impedes the progression of neurodegenerative symptoms characterizing HD, and that autophagy is a promising therapeutic target for treating this pathology. In humans, AUTEN-67 may have the potential to delay the onset and decrease the severity of HD.

Topics: Animals; Animals, Genetically Modified; Autophagy; Brain; Disease Models, Animal; Disease Progression; Drosophila; Drosophila Proteins; Humans; Huntingtin Protein; Huntington Disease; Naphthoquinones; Neurodegenerative Diseases; Neuroprotective Agents; Peptides; Statistics, Nonparametric; Sulfonamides

Ionizing radiation (IR) is a key therapeutic regimen for many head and neck cancers (HNC). However, the 5-year overall survival rate for locally advanced HNCs is approximately 50% and better therapeutic efficacy is needed.. quinone oxidoreductase 1 (NQO1) is overexpressed in many cancers, and β-lapachone (β-lap), a unique NQO1 bioactivatable drug, exploits this enzyme to release massive reactive oxygen species (ROS) that synergize with IR to kill by programmed necrosis. β-Lap represents a novel therapeutic opportunity in HNC leading to tumor-selective lethality that will enhance the efficacy of IR. Immunohistochemical staining and Western blot assays were used to assess the expression levels of NQO1 in HNC cells and tumors. Forty-five percent of endogenous HNCs expressed elevated NQO1 levels. In addition, multiple HNC cell lines and tumors demonstrated elevated levels of NQO1 expression and activity and were tested for anticancer lethality and radiosensitization by β-lap using long-term survival assays. The combination of nontoxic β-lap doses and IR significantly enhanced NQO1-dependent tumor cell lethality, increased ROS, TUNEL-positive cells, DNA damage, NAD(+), and ATP consumption, and resulted in significant antitumor efficacy and prolonged survival in two xenograft murine HNC models, demonstrating β-lap radiosensitization of HNCs through a NQO1-dependent mechanism. This translational study offers a potential biomarker-driven strategy using NQO1 expression to select tumors susceptible to β-lap-induced radiosensitization. Mol Cancer Ther; 15(7); 1757-67. ©2016 AACR.

Topics: Adenosine Triphosphate; Animals; Catalase; Cell Death; Cell Line, Tumor; Cell Survival; Disease Models, Animal; Enzyme Activation; Gene Expression; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms; Humans; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Radiation Tolerance; Radiation-Sensitizing Agents; Radiation, Ionizing; Reactive Oxygen Species; Survival Analysis; Xenograft Model Antitumor Assays

Candida albicans and Staphylococcus aureus are opportunistic pathogens. Despite causing a number of independent infections, both pathogens can co-infect to cause urinary tract infections, skin infections, biofilm associated infections, sepsis and pneumonia. Infections of these two pathogens especially their biofilm associated infections are often difficult to treat using currently available anti-bacterial and anti-fungal agents. In order to identify a common anti-microbial agent which could confer a broad range of protection against their infections, we screened several phytochemicals and identified plumbagin (5-hydroxy-2-methyl-1,4-naphthoquinone), a phytochemical from Plumbago species as a potent antimicrobial agent against S. aureus and C. albicans, with a minimum inhibitory concentration of 5μg/ml. Antimicrobial activity of plumbagin was validated using an ex-vivo porcine skin model. For better understanding of the antimicrobial activity of plumbagin, a Drosophila melanogaster infection model was used, where D. melanogaster was infected using S. aureus and C. albicans, or with both organisms. The fly's survival rate was dramatically increased when infected flies were treated using plumbagin. Further, plumbagin was effective in preventing and dispersing catheter associated biofilms formed by these pathogens. The overall results of this work provides evidence that plumbagin, possesses an excellent antimicrobial activity which should be explored further for the treatment of S. aureus and C. albicans infections.

Topics: Animals; Anti-Infective Agents; Biofilms; Candida albicans; Candidiasis; Disease Models, Animal; Drosophila melanogaster; Female; Microbial Sensitivity Tests; Naphthoquinones; Phytochemicals; Plumbaginaceae; Staphylococcal Infections; Staphylococcus aureus; Survival Analysis; Treatment Outcome

Stimulation of transient receptor potential ankyrin 1 (TRPA1), which abundantly expressed in enterochromaffin cells (ECC), has been reported to exert apparently contradictory results in in vitro contractility and in vivo gastrointestinal (GI) transit evaluations. The pharmaceutical-grade Japanese traditional medicine daikenchuto (TU-100) has been reported to be beneficial for postoperative ileus (POI) and accelerate GI transit in animals and humans. TU-100 was recently shown to increase intestinal blood flow via stimulation of TRPA1 in the epithelial cells of the small intestine (SI).. The effects of various TRPA1 agonists on motility were examined in a manipulation-induced murine POI model, in vitro culture of SI segments and an ECC model cell line, RIN-14B.. Orally administered TRPA1 agonists, aryl isothiocyanate (AITC) and cinnamaldehyde (CA), TU-100 ingredients, [6]-shogaol (6S) and γ-sanshool (GS), improved SI transit in a POI model. The effects of AITC, 6S and GS but not CA were abrogated in TRPA1-deficient mice. SI segments show periodic peristaltic motor activity whose periodicity disappeared in TRPA1-deficient mice. TU-100 augmented the motility. AITC, CA and 6S increased 5-HT release from isolated SI segments and the effects of all these compounds except for CA were lost in TRPA1-deficient mice. 6S and GS induced a release of 5-HT from RIN-14B cells in a dose- and TRPA1-dependent manner.. Intraluminal TRPA1 stimulation is a potential therapeutic strategy for GI motility disorders. Further investigation is required to determine whether 5-HT and/or ECC are involved in the effect of TRPA1 on motility.

Topics: Acrolein; Amides; Animals; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Gastrointestinal Transit; Ileus; Male; Mice; Mice, 129 Strain; Mice, Inbred C57BL; Naphthoquinones; Organ Culture Techniques; TRPA1 Cation Channel

Plasminogen activator inhibitor-1 (PAI-1) is a key negative regulator of the fibrinolytic system. Elevated levels of PAI-1 are associated with thrombosis and cardiovascular and metabolic diseases. Inhibition of PAI-1 activity represents a new strategy for antithrombotic and antifibrinolysis therapies. In this study, we systematically investigated the inhibitory effect of shikonin on PAI-1 activity. In the chromogenic substrate-based urokinase (uPA)/PAI-1 assay, we found that shikonin inhibited human PAI-1 activity with IC50 values of 30.68±2.32μM. This result was further confirmed by urokinase-type plasminogen activator (uPA)-mediated clot lysis assay. Mechanistic studies indicated that shikonin directly could bind to PAI-1 and prevent the binding of PAI-1 to uPA in a dose-dependent manner. Shikonin also blocked the formation of PAI-1/uPA complex, as shown by SDS/PAGE analysis. In the mouse arterial thrombosis model, intraperitoneal injection of shikonin at 1mgkg(-1) dose significantly prolonged tail bleeding time from 12.956±4.457min to 26.576±2.443min. It also reduced arterial thrombus weight from 0.01±0.001g to 0.006±0.001g (p<0.05). In a liver fibrosis treatment model, when shikonin was continuously injected intraperitoneally at a dose of 1mgkg(-1) over a two-week period, the hydroxyproline content in the mice plasma was significantly reduced and the degree of liver fibrosis was decreased significantly. Thus, shikonin may represent a novel small molecule inhibitor of PAI-1 that could have become a lead drug the treatment of thrombus and fibrosis.

Topics: Animals; Disease Models, Animal; Humans; Liver Cirrhosis; Mice; Naphthoquinones; Plasminogen Activator Inhibitor 1; Thrombosis; Urokinase-Type Plasminogen Activator

Pterocarpanquinone (+/-)-LQB-118 presents antineoplastic and antiparasitic properties and also shows great inhibitory effect on TNF-α release in vitro. Here, its anti-inflammatory activity was evaluated in a lipopolysaccharide (LPS)-induced lung inflammation model in C57BL/6 mice. LPS inhalation induced a marked neutrophil infiltration to the lungs which was reduced by intraperitoneal treatment with (+/-)-LQB-118 in a similar manner to that of dexamethasone and even better than that of acetylsalicylic acid. Moreover, (+/-)-LQB-118 administration resulted in decrease of NF-κB activation and KC level in lungs, with a pronounced inhibitory effect on TNF-α release, measured in bronchoalveolar lavage fluid. Trying to understand the anti-inflammatory mechanism by which (+/-)-LQB-118 acts, we performed a molecular modeling analysis, including docking to estrogen receptors α and β. Results suggested that (+/-)-LQB-118 may bind to both receptors, with a similar orientation to 17-β-estradiol. Together, these results showed that (+/-)-LQB-118 exhibits an anti-inflammatory effect, most likely by inhibiting TNF-α release and NF-κB activation, which may be related to the estrogen receptor binding.

Topics: Animals; Anti-Inflammatory Agents; Disease Models, Animal; Hydrogen Bonding; Inflammation; Lung Diseases; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; NF-kappa B; Pterocarpans; Receptors, Estrogen; Thermodynamics

Mycobacterium tuberculosis remains a global health threat largely due to the lengthy duration of curative antibiotic treatment, contributing to medical nonadherence and the emergence of drug resistance. This prolonged therapy is likely due to the presence of M. tuberculosis persisters, which exhibit antibiotic tolerance. Inorganic polyphosphate [poly(P)] is a key regulatory molecule in the M. tuberculosis stringent response mediating antibiotic tolerance. The polyphosphate kinase PPK1 is responsible for poly(P) synthesis in M. tuberculosis, while the exopolyphosphatases PPX1 and PPX2 and the GTP synthase PPK2 are responsible for poly(P) hydrolysis. In the present study, we show by liquid chromatography-tandem mass spectrometry that poly(P)-accumulating M. tuberculosis mutant strains deficient in ppx1 or ppk2 had significantly lower intracellular levels of glycerol-3-phosphate (G3P) and 1-deoxy-xylulose-5-phosphate. Real-time PCR revealed decreased expression of genes in the G3P synthesis pathway in each mutant. The ppx1-deficient mutant also showed a significant accumulation of metabolites in the tricarboxylic acid cycle, as well as altered arginine and NADH metabolism. Each poly(P)-accumulating strain showed defective biofilm formation, while deficiency of ppk2 was associated with increased sensitivity to plumbagin and meropenem and deficiency of ppx1 led to enhanced susceptibility to clofazimine. A DNA vaccine expressing ppx1 and ppk2, together with two other members of the M. tuberculosis stringent response, M. tuberculosis rel and sigE, did not show protective activity against aerosol challenge with M. tuberculosis, but vaccine-induced immunity enhanced the killing activity of isoniazid in a murine model of chronic tuberculosis. In summary, poly(P)-regulating factors of the M. tuberculosis stringent response play an important role in M. tuberculosis metabolism, biofilm formation, and antibiotic sensitivity in vivo.

Topics: Acid Anhydride Hydrolases; Animals; Antitubercular Agents; Biofilms; Citric Acid Cycle; Clofazimine; Disease Models, Animal; Drug Resistance, Bacterial; Gene Expression; Glycerophosphates; Isoenzymes; Isoniazid; Meropenem; Mice; Mycobacterium tuberculosis; Naphthoquinones; Phosphotransferases (Phosphate Group Acceptor); Polyphosphates; Thienamycins; Tuberculosis Vaccines; Tuberculosis, Multidrug-Resistant; Vaccines, DNA; Xylose

β,β-dimethylacryloyl alkannin (DMA) is a key component of Lithospermum and possesses good efficacy for treating psoriasis. DMA inhibits activated dendritic cells (DCs), but the mechanism is unknown. Therefore, this study aimed to explore the modulation of the TLR7/8 pathway by DMA in psoriasis-activated DCs. Models of psoriasis-like skin lesions were established using BALB/c mice; 8 mice were treated with DMA (2.5mg/kg). Bone marrow cells were isolated and induced into DCs using R848, a TLR7/8 agonist. Splenic CD11c+ cells were detected by flow cytometry. Skin CD11c+ cells were detected by immunofluorescence. TLR7, TLR8, MYD88, and IRAKM proteins were detected by Western blot. The effects of DMA on surface molecules of DCs were observed by flow cytometry. mRNA expression of inflammatory factors was detected by qRT-PCR. Secreted cytokines were detected by cytometric bead array. Compared with the model group, psoriasis-like skin lesions were alleviated by DMA, the splenic CD11c+ cells were significantly decreased (P<0.01), and CD11c+ cell numbers in skin lesions were decreased (P<0.01). Expression levels of TLR7, MYD88, and IRAKM were significantly decreased (P<0.05). R848-stimulated DCs showed increased expression of I-A/I-E, CD80, and CD86 (P<0.01), increased IL-23 and IL-1β mRNA and secretion (P<0.05), and increased TLR7, TLR8, MYD88, and IRAKM expression (P<0.01); DMA inhibited all of these effects of the TLR7/8 pathway activation by R848 (P<0.05). In conclusion, DMA could inhibit psoriasis-activated DCs via the TLR7/8 pathway.

Topics: Animals; Cell Differentiation; Cells, Cultured; Dendritic Cells; Disease Models, Animal; Humans; Imidazoles; Interleukin-1 Receptor-Associated Kinases; Interleukin-1beta; Interleukin-23; Lithospermum; Male; Membrane Glycoproteins; Mice; Mice, Inbred BALB C; Myeloid Differentiation Factor 88; Naphthoquinones; Psoriasis; Skin; Toll-Like Receptor 7; Toll-Like Receptor 8

Sepsis, severe sepsis and septic shock are the main cause of mortality in non-cardiac intensive care units. Immunometabolism has been linked to sepsis; however, the precise mechanism by which metabolic reprogramming regulates the inflammatory response is unclear. Here we show that aerobic glycolysis contributes to sepsis by modulating inflammasome activation in macrophages. PKM2-mediated glycolysis promotes inflammasome activation by modulating EIF2AK2 phosphorylation in macrophages. Pharmacological and genetic inhibition of PKM2 or EIF2AK2 attenuates NLRP3 and AIM2 inflammasomes activation, and consequently suppresses the release of IL-1β, IL-18 and HMGB1 by macrophages. Pharmacological inhibition of the PKM2-EIF2AK2 pathway protects mice from lethal endotoxemia and polymicrobial sepsis. Moreover, conditional knockout of PKM2 in myeloid cells protects mice from septic death induced by NLRP3 and AIM2 inflammasome activation. These findings define an important role of PKM2 in immunometabolism and guide future development of therapeutic strategies to treat sepsis.

Topics: Animals; Carrier Proteins; Coinfection; Disease Models, Animal; DNA-Binding Proteins; eIF-2 Kinase; Female; Glycolysis; HMGB1 Protein; Humans; Inflammasomes; Interleukin-18; Interleukin-1beta; Macrophages; Male; Membrane Proteins; Mice; Mice, Inbred BALB C; Mice, Knockout; Myeloid Cells; Naphthoquinones; NLR Family, Pyrin Domain-Containing 3 Protein; Phosphorylation; Pyruvate Kinase; Sepsis; Signal Transduction; Thyroid Hormone-Binding Proteins; Thyroid Hormones

The ability of flavonoids to affect multiple key pathways of glucose toxicity, as well as to attenuate inflammation has been well documented. In this study, the inhibition of rat lens aldose reductase by 3,7-di-hydroxy-2-[4-(2-chloro-1,4-naphthoquinone-3-yloxy)-3-hydroxy-phenyl]-5-hydroxy-chromen-4-one (compound 1), was studied in greater detail in comparison with the parent quercetin (compound 2). The inhibition activity of 1, characterized by IC50 in low micromolar range, surpassed that of 2. Selectivity in relation to the closely related rat kidney aldehyde reductase was evaluated. At organ level in isolated rat lenses incubated in the presence of high glucose, compound 1 significantly inhibited accumulation of sorbitol in a concentration-dependent manner, which indicated that 1 was readily taken up by the eye lens cells and interfered with cytosolic aldose reductase. In addition, compound 1 provided macroscopic protection of colonic mucosa in experimental colitis in rats. At pharmacologically active concentrations, compound 1 and one of its potential metabolite 2-chloro-3-hydroxy-[1,4]-naphthoquinone (compound 3) did not affect osmotic fragility of red blood cells.

Topics: Aldehyde Reductase; Animals; Anti-Inflammatory Agents; Colitis; Disease Models, Animal; Erythrocytes; Glucose; Intestinal Mucosa; Kidney; Kinetics; Lens, Crystalline; Male; Naphthoquinones; Osmotic Fragility; Quercetin; Rats; Rats, Wistar; Sorbitol; Tissue Culture Techniques

Endothelial nitric oxide synthase (eNOS) is involved in blood pressure (BP) regulation through the production of nitric oxide. Sirtuin I (SIRT1), an NAD-dependent protein deacetylase, promotes vascular relaxation through deacetylation and activation of eNOS. β-Lapachone (βL) increases the cellular NAD(+)/NADH ratio by activating. quinone oxidoreductase 1 (NQO1). In this study, we verified whether activation of NQO1 by βL modulates BP through regulation of eNOS acetylation in a hypertensive animal model.. Spontaneously hypertensive rats (SHRs) and an endothelial cell line (bEnd.3 cells) were used to investigate the hypotensive effect of βL and its mechanism of action.. βL treatment significantly lowered the BP in SHRs, but this hypotensive effect was completely blocked by eNOS inhibition with ω-nitro-l-arginine methyl ester. In vitro studies revealed that βL activated eNOS, which was accompanied by an increased NAD(+)/NADH ratio. Moreover, βL significantly decreased acetylation of eNOS; however, this reduced eNOS acetylation was completely precluded by inhibition of SIRT1 in the bEnd.3 cells and in the aorta of the SHRs. Consistent with these effects, βL-induced reduction in BP was also abolished by SIRT1 inhibition in the SHRs.. To the best of our knowledge, this is the first study to demonstrate that eNOS acetylation can be regulated by NQO1 activation in an SIRT1-dependent manner, which is correlated with the relief of hypertension. These findings provide strong evidence that NQO1 might be a new therapeutic target for hypertension.

Topics: Acetylation; Animals; Antihypertensive Agents; Blood Pressure; Cell Line; Disease Models, Animal; Endothelial Cells; Enzyme Activation; Enzyme Activators; Enzyme Inhibitors; Humans; Hypertension; Male; Mice; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Nitric Oxide Synthase Type III; Protein Processing, Post-Translational; Rats, Inbred SHR; Sirtuin 1; Time Factors

Maintaining cellular redox homeostasis is imperative for the survival and normal functioning of cells. This study describes the role and regulation of MAPKinases in oxidative stress mediated apoptosis. Plumbagin, a vitamin K3 analog and a pro-oxidant, was employed and it induced apoptosis in both mouse and human T-cell lymphoma cell lines via increased oxidative stress, caspase activity and loss of mitochondrial membrane potential. The pro-oxidant and cytotoxic effects of plumbagin were sensitive to antioxidants indicating a decisive role of cellular redox balance. Plumbagin induced persistent activation of JNK and pharmacological inhibition as well as shRNA-mediated JNK knock-down rescued cells from plumbagin-induced apoptosis. Further, plumbagin induced cytochrome c release, FasL expression and Bax levels via activation of JNK pathway. Exposure of lymphoma cells to plumbagin led to inhibition of total and specific phosphatase activity, increased total protein S-glutathionylation and induced glutathionylation of dual specific phosphatase- 1 and 4 (MKP-1 and MKP-2). The in vivo anti-tumor efficacy of plumbagin was demonstrated using a mouse model. In conclusion, oxidative stress mediated tumor cytotoxicity operates through sustained JNK activation via a novel redox-mediated regulation of MKP-1 and MKP-2.

Topics: Animals; Antineoplastic Agents, Phytogenic; Apoptosis; Disease Models, Animal; Dual Specificity Phosphatase 1; Dual-Specificity Phosphatases; Enzyme Activation; Glutathione; Humans; Jurkat Cells; Lymphoma, T-Cell; Male; MAP Kinase Signaling System; Mice; Mice, Inbred C57BL; Mitogen-Activated Protein Kinase Phosphatases; Models, Molecular; Naphthoquinones; Oxidative Stress; Phosphorylation; Random Allocation

To test the hypothesis that chronic hypoxic pulmonary hypertension (CH-PH) is associated with increased survivin and decreased voltage-gated potassium (KV) channels expression in pulmonary arteries, rats were randomized as: normoxia (N); normoxia + YM155, survivin suppressor (NY); hypoxia (H); hypoxia + YM155 (HY). HY group had significantly reduced pulmonary arterial pressure, right ventricular weight and right ventricular hypertrophy compared with H group. Survivin mRNA and protein were detected in pulmonary arteries of rats with CH-PH, but not rats without CH-PH. YM155 downregulated survivin protein and mRNA. KV channel expression and activity were upregulated after YM155 treatment. Survivin may play a role in the pathogenesis of CH-PH.

Topics: Animals; Chronic Disease; Disease Models, Animal; Gene Expression Regulation; Hypertension, Pulmonary; Hypoxia; Imidazoles; Male; Microtubule-Associated Proteins; Muscle, Smooth, Vascular; Naphthoquinones; Patch-Clamp Techniques; Potassium Channels, Voltage-Gated; Pulmonary Wedge Pressure; Rats; Rats, Wistar; Real-Time Polymerase Chain Reaction; RNA; Survivin

YM155, a small molecule inhibitor of the antiapoptotic protein survivin, has been developed as a potential anti-cancer drug. We investigated a combination therapy of YM155 and interleukin-2 (IL-2) in a mouse model of renal cell carcinoma (RCC). YM155 caused cell cycle arrest and apoptosis in renal cancer (RENCA) cells. Next, luciferase-expressing RENCA cells were implanted in the left kidney and the lung of BALB/c mice to develop RCC metastatic model. In this orthotopic renal and metastatic lung tumors models, YM155 and IL-2 additively decreased tumor weight, lung metastasis, and luciferin-stained tumor images. Also, the combination significantly suppressed regulatory T cells and myeloid-derived suppressor cells compared with single agent treatment. We suggest that a combination of YM155 and IL-2 can be tested as a potential therapeutic modality in patients with RCC.

Topics: Animals; Antineoplastic Agents; Antineoplastic Combined Chemotherapy Protocols; Carcinoma, Renal Cell; CD4-Positive T-Lymphocytes; Cell Line, Tumor; Cell Proliferation; Cell Separation; Disease Models, Animal; Female; Flow Cytometry; Gene Expression Regulation, Neoplastic; Humans; Imidazoles; Inhibitor of Apoptosis Proteins; Interleukin-2; Kidney Neoplasms; Mice; Mice, Inbred BALB C; Naphthoquinones; Neoplasm Metastasis; Neoplasm Transplantation; Survivin; T-Lymphocytes, Regulatory

β-Lapachone (β-LAP) is a natural naphthoquinone compound isolated from the lapacho tree (Tabebuia sp.), and it has been used for treatment of rheumatoid arthritis, infection, and cancer. In the present study, we investigated whether β-LAP has anti-inflammatory effects under in vitro and in vivo neuroinflammatory conditions.. The effects of β-LAP on the expression of inducible nitric oxide synthase (iNOS), cytokines, and matrix metalloproteinases (MMPs) were examined in lipopolysaccharide (LPS)-stimulated BV2 microglial cells and rat primary microglia by ELISA, reverse transcription polymerase chain reaction (RT-PCR), and Western blot analysis. Microglial activation and the expression levels of proinflammatory molecules were measured in the LPS-injected mouse brain by immunohistochemistry and RT-PCR analysis. The detailed molecular mechanism underlying the anti-inflammatory effects of β-LAP was analyzed by electrophoretic mobility shift assay, reporter gene assay, Western blot, and RT-PCR analysis.. β-LAP inhibited the expression of iNOS, proinflammatory cytokines, and MMPs (MMP-3, MMP-8, MMP-9) at mRNA and protein levels in LPS-stimulated microglia. On the other hand, β-LAP upregulated the expressions of anti-inflammatory molecules such as IL-10, heme oxygenase-1 (HO-1), and the tissue inhibitor of metalloproteinase-2 (TIMP-2). The anti-inflammatory effect of β-LAP was confirmed in an LPS-induced systemic inflammation mouse model. Thus, β-LAP inhibited microglial activation and the expressions of iNOS, proinflammatory cytokines, and MMPs in the LPS-injected mouse brain. Further mechanistic studies revealed that β-LAP exerts anti-inflammatory effects by inhibiting MAPKs, PI3K/AKT, and NF-κB/AP-1 signaling pathways in LPS-stimulated microglia. β-LAP also inhibited reactive oxygen species (ROS) production by suppressing the expression and/or phosphorylation of NADPH oxidase subunit proteins, such as p47(phox) and gp91(phox). The anti-oxidant effects of β-LAP appeared to be related with the increase of HO-1 and NQO1 via the Nrf2/anti-oxidant response element (ARE) pathway and/or the PKA pathway.. The strong anti-inflammatory/anti-oxidant effects of β-LAP may provide preventive therapeutic potential for various neuroinflammatory disorders.

Topics: Animals; Anti-Inflammatory Agents; Cell Line; Cells, Cultured; Cytokines; Disease Models, Animal; Encephalitis; Heme Oxygenase-1; In Vitro Techniques; Interleukin-10; Lipopolysaccharides; Matrix Metalloproteinases; Mice; Microglia; Naphthoquinones; Nitric Oxide Synthase Type II; Nitrites; Rats; Rats, Sprague-Dawley; Reactive Oxygen Species; Signal Transduction; Tissue Inhibitor of Metalloproteinase-2

To investigate the effect of β, β-dimethylacryloyl alkannin, a main component of Lithospermum erythrorhizon, on activated dendritic cells (DCs) in a psoriasis mouse model.. BALB/c mice were used to establish the animal model for psoriasis-like skin lesion; alkannin at 10 mg/kg (high), 5 mg/kg (medium), 2.5 mg/kg (low), respectively, were intragastrically administered. Psoriasis area and severity index (PASI) was used to evaluate the skin lesions. Histological changes, the thickness of epidermis, and the quantity of interleukin (IL)-23 in skin lesion were measured. In in vitro experiments, mononuclear cells in peripheral blood from healthy people were isolated, and monocytes were obtained. DCs with a mature state in differentiation and function were obtained through in vitro induction with several cytokines, and identified by flow cytometry. The influence of DCs on proliferation of allogenic lymphocytes was analyzed. The influence of alkannin on messenger ribonucleic acid (mRNA) expression of pro-inflammatory factors by mature DCs was evaluated using reverse transcriptase polymerase chain reaction.. Mice treated with alkannin at varying concentration showed obvious remission in psoriasis-like skin lesion compared to control group, with decreased PASI score, obviously reduced vertical thickness of epidermis. Besides, alkannin treatment decreased the expression of IL-23 in skin lesion. Alkannin (12.5 μg/mL) suppressed the ability of DCs to stimulate the proliferation of allogenic lymphocytes, and suppressed the expression and secretion of IL-6, IL-12 p40, IL-23, IL-1β, tumor necrosis factor-α mRNA and proteins, respectively.. β, β-dimethylacryloyl alkannin could suppress the function of activated DCs in imiquimod-induced psoriasis mouse model.

Topics: Aminoquinolines; Animals; Cell Proliferation; Cells, Cultured; Coculture Techniques; Cytokines; Dendritic Cells; Dermatologic Agents; Disease Models, Animal; Humans; Imiquimod; Inflammation Mediators; Lymphocyte Activation; Lymphocytes; Male; Mice, Inbred BALB C; Naphthoquinones; Psoriasis; Severity of Illness Index; Skin; Time Factors

Plumbagin has been reported to modulate cellular redox status and suppress NF-κB. In the present study, we investigated the effect of plumbagin on lipopolysaccharide (LPS)-induced endotoxic shock, oxidative stress and inflammatory parameters in vitro and in vivo. Plumbagin inhibited LPS-induced nitric oxide, TNF-α, IL-6 and prostaglandin-E2 production in a concentration-dependent manner in RAW 264.7 cells without inducing any cell death. Plumbagin modulated cellular redox status in RAW cells. Plumbagin treatment significantly reduced MAPkinase and NF-κB activation in macrophages. Plumbagin prevented mice from endotoxic shock-associated mortality and decreased serum levels of pro-inflammatory markers. Plumbagin administration ameliorated LPS-induced oxidative stress in peritoneal macrophages and splenocytes. Plumbagin also attenuated endotoxic shock-associated changes in liver and lung histopathology and decreased the activation of ERK and NF-κB in liver. These findings demonstrate the efficacy of plumbagin in preventing LPS-induced endotoxemia and also provide mechanistic insights into the anti-inflammatory effects of plumbagin.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Cell Line; Dinoprostone; Disease Models, Animal; Dose-Response Relationship, Drug; Down-Regulation; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Inflammation Mediators; Interleukin-6; Lipopolysaccharides; Liver; Lung; Macrophages; Male; Mice; Naphthoquinones; NF-kappa B; Nitric Oxide; Oxidative Stress; Shock, Septic; Signal Transduction; Spleen; Time Factors; Tumor Necrosis Factor-alpha

Alcohol-induced liver injury is the most common liver disease in which fatty acid metabolism is altered. It is thought that altered NAD(+)/NADH redox potential by alcohol in the liver causes fatty liver by inhibiting fatty acid oxidation and the activity of tricarboxylic acid cycle reactions. β-Lapachone (βL), a naturally occurring quinone, has been shown to stimulate fatty acid oxidation in an obese mouse model by activating adenosine monophosphate-activated protein kinase (AMPK). In this report, we clearly show that βL reduced alcohol-induced hepatic steatosis and induced fatty acid oxidizing capacity in ethanol-fed rats. βL treatment markedly decreased hepatic lipids while serum levels of lipids and lipoproteins were increased in rats fed ethanol-containing liquid diets with βL administration. Furthermore, inhibition of lipolysis, enhancement of lipid mobilization to mitochondria and upregulation of mitochondrial β-oxidation activity in the soleus muscle were observed in ethanol/βL-treated animals compared to the ethanol-fed rats. In addition, the activity of alcohol dehydrogenase, but not aldehyde dehydrogenase, was significantly increased in rats fed βL diets. βL-mediated modulation of NAD(+)/NADH ratio led to the activation of AMPK signaling in these animals.. Our results suggest that improvement of fatty liver by βL administration is mediated by the upregulation of apoB100 synthesis and lipid mobilization from the liver as well as the direct involvement of βL on NAD(+)/NADH ratio changes, resulting in the activation of AMPK signaling and PPARα-mediated β-oxidation. Therefore, βL-mediated alteration of NAD(+)/NADH redox potential may be of potential therapeutic benefit in the clinical setting.

Topics: Alcohol Dehydrogenase; Aldehyde Dehydrogenase; AMP-Activated Protein Kinases; Animals; Cells, Cultured; Diet, High-Fat; Disease Models, Animal; Ethanol; Fatty Acids; Fatty Liver, Alcoholic; Hepatocytes; Lipid Metabolism; Lipid Peroxidation; Male; Naphthoquinones; Rats; Rats, Sprague-Dawley; Reverse Transcriptase Inhibitors; Signal Transduction

Epilepsy is a debilitating disease affecting 1-2% of the world's population. Despite this high prevalence, 30% of patients suffering from epilepsy are not successfully managed by current medication suggesting a critical need for new anti-epileptic drugs (AEDs). In an effort to discover new therapeutics for the management of epilepsy, we began our study by screening drugs that, like some currently used AEDs, inhibit histone deacetylases (HDACs) using a well-established larval zebrafish model. In this model, 7-day post fertilization (dpf) larvae are treated with the widely used seizure-inducing compound pentylenetetrazol (PTZ) which stimulates a rapid increase in swimming behavior previously determined to be a measurable manifestation of seizures. In our first screen, we tested a number of different HDAC inhibitors and found that one, 2-benzamido-1 4-naphthoquinone (NQN1), significantly decreased swim activity to levels equal to that of valproic acid, 2-n-propylpentanoic acid (VPA). We continued to screen structurally related compounds including Vitamin K3 (VK3) and a number of novel Vitamin K (VK) analogs. We found that VK3 was a robust inhibitor of the PTZ-induced swim activity, as were several of our novel compounds. Three of these compounds were subsequently tested on mouse seizure models at the National Institute of Neurological Disorders and Stroke (NINDS) Anticonvulsant Screening Program. Compound 2h reduced seizures particularly well in the minimal clonic seizure (6Hz) and corneal-kindled mouse models of epilepsy, with no observable toxicity. As VK3 affects mitochondrial function, we tested the effects of our compounds on mitochondrial respiration and ATP production in a mouse hippocampal cell line. We demonstrate that these compounds affect ATP metabolism and increase total cellular ATP. Our data indicate the potential utility of these and other VK analogs for the prevention of seizures and suggest the potential mechanism for this protection may lie in the ability of these compounds to affect energy production.

Topics: Adenosine Triphosphate; Animals; Anticonvulsants; Cell Line; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Interactions; Enzyme Inhibitors; Epilepsy; Mice; Naphthoquinones; Oxygen Consumption; Pentylenetetrazole; Proto-Oncogene Proteins c-fos; Swimming; Time Factors; Vitamin K 3; Zebrafish

This study reports the in vivo anti-inflammatory and antioxidative effects of the methanolic extract of the aerial parts of Mitracarpus frigidus (MFM) and its chemical fingerprint.. The acute anti-inflammatory activity was performed using the carrageenan-induced paw oedema and peritonitis, ear oedema induced by croton oil and ethyl phenylpropiolate methods. Total COX, COX-1 and COX-2 expression was also evaluated. Chronic activity was determined by cotton pellet granuloma model. The antioxidative activity was assessed using liver tissue malondialdehyde, catalase and myeloperoxidase activities.. M. frigidus showed an intense acute anti-inflammatory action (100 and 300 mg/kg) in a nondose-dependent manner with selective inhibition of COX-2 expression. This activity may be also related to the strong antioxidative effect observed. By the other side, the chronic anti-inflammatory activity of MFM was not expressive. Kaempferol, kaempferol-O-rutenoside, rutin, ursolic acid and psychorubrin were identified in MFM.. The anti-inflammatory activity of MFM was probably due to inhibition of COX expression in a selective manner for COX-2. Other mechanisms, such as inhibition of inflammatory mediators and of the oxidative stress were possibly involved in the effects observed. To the best of our knowledge, it is the first time those activities are reported for M. frigidus.

Topics: Animals; Antioxidants; Cyclooxygenase 2; Cyclooxygenase 2 Inhibitors; Disease Models, Animal; Edema; Female; Inflammation; Inflammation Mediators; Kaempferols; Male; Mice; Naphthoquinones; Oxidative Stress; Phytotherapy; Plant Components, Aerial; Plant Extracts; Rats, Wistar; Rubiaceae; Rutin; Triterpenes; Ursolic Acid

Research into novel therapeutic strategies for schizophrenia with high efficacy and low side effects has been progressed in recent years. In the present study, anti-schizophrenia activities of 2-(dimethylamino)- and 2-(methylamino)- 7H-naphtho[1,2,3-de]quinolin-7-one derivatives (D1-D10) have been evaluated in ketamine-induced experimental schizophrenia model in mice. For this aim, experimental animals was submitted to ketamine intraperitoneal injection at 100 mg/kg/day. Then, D1-D10 were administrated intra-cerebroventricularly to mice and in next step, animals depressive-like behaviors have been examined by despair swimming test. The obtained results demonstrate that 7H-naphtho[1,2,3- de]quinolin-7-one derivatives, specifically D9, reduced depressive-like behaviors via the decrease of the immobility time and the increase of the swim and climb times. Overall, these results showed that these alkaloids have anti-schizophrenia efficacy and due to their low side effects, they can be used as a new strategy for the treatment of depressive symptoms of schizophrenia patients.

Topics: Animals; Antipsychotic Agents; Aporphines; Disease Models, Animal; Ketamine; Male; Mice; Naphthoquinones; Psychotic Disorders; Schizophrenia; Swimming

The available treatment for the prevention and cure of Chagas disease, caused by the protozoan Trypanosoma cruzi, is still unsatisfactory. Thus, there is an urgent need to develop new drugs. In the last few years, our research group has focused on finding a new chemical entity able to target the infectious bloodstream trypomastigotes. In this study, we assayed 16 β-lapachone analogous with modifications in the pyran and aromatic ring to find a new prototype with high trypanocidal activity. Interestingly, two ortho-naphthoquinones presented the best trypanocidal profile (8c and 8d with an IC50/24 h of 26.9 ± 1.3 and 23.5 ± 2.5 μM, respectively), which were 4 to 17 times more effective than β-lapachone (391.5 ± 16.5 μM) and the standard drug benznidazole (103.6 ± 0.6 μM). The introduction of a hydroxyl group on the compounds' aromatic ring modulated their biological profile by increasing their activity not only for cancer cells (MDAMB435), as previously described in literature, but also against T. cruzi. The Structure-Activity Relationship (SAR) study indicated that this introduction modulated HOMO and MEP parameters, improving the trypanocidal activity.

Topics: Animals; Chagas Disease; Disease Models, Animal; Inhibitory Concentration 50; Mice; Models, Biological; Models, Molecular; Molecular Structure; Naphthoquinones; Parasitic Sensitivity Tests; Pyrans; Structure-Activity Relationship; Trypanocidal Agents; Trypanosoma cruzi

Plumbagin is the major active constituent in several plants including Plumbago indica Linn. (root). This compound has been shown to exhibit a wide spectrum of biological and pharmacological activities. The present study aimed to evaluate the in vitro and in vivo antimalarial activity of plumbagin including its acute and subacute toxicity in mice.. In vitro antimalarial activity of plumbagin against K1 and 3D7 Plasmodium falciparum clones were assessed using SYBR Green I based assay. In vivo antimalarial activity was investigated in Plasmodium berghei-infected mouse model (a 4-day suppressive test).. Plumbagin exhibited promising antimalarial activity with in vitro IC50 (concentration that inhibits parasite growth to 50%) against 3D7 chloroquine-sensitive P. falciparum and K1 chloroquine-resistant P. falciparum clones of 580 (270-640) and 370 (270-490) nM, respectively. Toxicity testing indicated relatively low toxicity at the dose levels up to 100 (single oral dose) and 25 (daily doses for 14 days) mg/kg body weight for acute and subacute toxicity, respectively. Chloroquine exhibited the most potent antimalarial activity in mice infected with P. berghei ANKA strain with respect to its activity on the reduction of parasitaemia on day 4 and the prolongation of survival time.. Plumbagin at the dose of 25 mg/kg body weight given for 4 days was safe and produced weak antimalarial activity. Chemical derivatization of the parent compound or preparation of modified formulation is required to improve its systemic bioavailability.

Topics: Animals; Antimalarials; Biological Availability; Body Weight; Chloroquine; Disease Models, Animal; Female; In Vitro Techniques; Malaria; Male; Mice; Mice, Inbred ICR; Naphthoquinones; Plasmodium berghei; Plasmodium falciparum; Toxicity Tests

Zicao is a traditional wound healing herbal medicine that has been used for several hundred years in China. A survey of the published literatures revealed that arnebin-1, one of the naphthoquinone derivatives, played the most important role in wound healing property of this plant. However, whether arnebin-1 affects angiogenesis in vitro and has an effect on wound healing process in diabetic rats remains enigmatic. To investigate the effect of arnebin-1 with or without VEGF on proliferation, migration and tube formation of HUVECs in vitro and the effect of its topical application in the form of ointment on wound healing in a cutaneous punch wound model of alloxan-induced diabetic rats in vivo.. The pro-angiogenic functions of arnebin-1 on HUVECs including proliferation, migration and angiogenesis were evaluated through MTT assay, wound healing assay, transwell assay and tube formation assay in vitro. Male Sprague-Dawley rats were injected intraperitoneally with alloxan to induce type І diabetic rats. Three wounds were created in each rat on the dorsal surface, and then divided to be basement treated, arnebin-1 ointment treated and untreated group correspondingly. The indicators including wound closure rate and histological evaluation were investigated on day 4 and 7 post-wounding.. Without VEGF, arnebin-1 did not affect the proliferation of HUVECs significantly, but had a positive effect on cell migration and tube formation. However, in the presence of minimal VEGF, Arnebin-1 could increase the proliferation, enhance the migration and promote the tube formation of HUVECs significantly. The wound closure rate was increased significantly in arnebin-1 treated group compared to that of untreated and basement treated groups in diabetic rats, and the histological evaluation also showed well organized dermal layer, reduced number of macrophages, increased number of fibroblasts, remarkable degree of neovascularization and epithelization in arnebin-1 treated group.. These findings suggest that arnebin-1 has a pro-angiogenic effect, and a synergetic effect with VEGF promotes the wound healing process in diabetic rats.

Topics: Alloxan; Animals; Cell Proliferation; Cells, Cultured; Diabetes Mellitus, Experimental; Disease Models, Animal; Human Umbilical Vein Endothelial Cells; Humans; Male; Naphthoquinones; Neovascularization, Physiologic; Rats; Rats, Sprague-Dawley; Wound Healing

Plumbagin (PL, 5-hydroxy-2-methyl-1,4-naphthoquinone) is a herbal compound derived from medicinal plants of the Droseraceae, Plumbaginaceae, Dioncophyllaceae, and Ancistrocladaceae families. Reports have shown that PL exerts immunomodulatory activity and may be a novel drug candidate for immune-related disease therapy. However, its effects on dendritic cells (DCs), the most potent antigen-presenting cells (APCs), remain unclear. In this study, we demonstrate that PL inhibits the differentiation, maturation, and function of human monocyte-derived DCs. PL can also restrict the expression of Th1- and Th17-polarizing cytokines in mDC. In addition, PL suppresses DCs both in vitro and in vivo, as demonstrated by its effects on the mouse DC line DC2.4 and mice with experimental autoimmune encephalomyelitis (EAE), respectively. Notably, PL ameliorated the clinical symptoms of EAE, including central nervous system (CNS) inflammation and demyelination. Our results demonstrate the immune suppressive and anti-inflammatory properties of PL via its effects on DCs and suggest that PL could be a potential treatment for DC-related autoimmune and inflammatory diseases.

Topics: Adjuvants, Immunologic; Animals; Antigens, CD; Apoptosis; CD4-Positive T-Lymphocytes; Cell Differentiation; Cell Proliferation; Cytokines; Dendritic Cells; Disease Models, Animal; Encephalomyelitis, Autoimmune, Experimental; Endocytosis; Female; Lipopolysaccharides; Mice; Mice, Inbred C57BL; Naphthoquinones; Spinal Cord

The potential benefit of vitamin K as a therapeutic in osteoporosis is controversial and the vitamin K regimen being used clinically (45 mg/day) employs doses that are many times higher than required to ensure maximal gamma-carboxylation of the vitamin K-dependent bone proteins. We therefore tested the hypothesis that vitamin K catabolites, 5-carbon (CAN5C) and 7-carbon carboxylic acid (CAN7C) aliphatic side-chain derivatives of the naphthoquinone moiety exert an osteotrophic role consistent with the treatment of osteoporosis.. Osteoblast-like MG63 cell cultures were challenged with lipopolysaccharide and the levels of interleukin-6, an osteoclastogenic cytokine, measured with and without catabolites; low concentrations of CAN7C significantly inhibited interleukin-6 release, but CAN5C did not. In models of bone loss induced by ovariectomy or sciatic neurectomy in C57BL/6 mice, we found that the rarer CAN7C catabolite markedly restricted ovariectomy-induced bone loss and possibly limited sciatic neurectomy-induced bone loss. CAN7C activity depends on a free carboxylic acid and its particular side-chain structure.. These in vivo data indicate for the first time that the clinical utility of vitamin K for osteoporosis may reside in an unusual catabolite.

Topics: Animals; Bone Density Conservation Agents; Carboxylic Acids; Cell Line; Cell Proliferation; Denervation; Disease Models, Animal; Female; Humans; Injections, Intraperitoneal; Interleukin-6; Methylation; Mice, Inbred C57BL; Molecular Structure; Naphthoquinones; Osteoblasts; Osteoporosis, Postmenopausal; Ovariectomy; Random Allocation; Sciatic Nerve; Structure-Activity Relationship; Vitamin K

Due to the recent advances of atovaquone, a naphthoquinone, through clinical trials as treatment for malarial infection, 19 quinone derivatives with previously reported structures were also evaluated for blood schizonticide activity against the malaria parasite Plasmodium falciparum. These compounds include 2-hydroxy-3-methylamino naphthoquinones (2-9), lapachol (10), nor-lapachol (11), iso-lapachol (12), phthiocol (13) and phenazines (12-20). Their cytotoxicities were also evaluated against human hepatoma and normal monkey kidney cell lines. Compounds 2 and 5 showed the highest activity against P. falciparum chloroquine-resistant blood-stage parasites (clone W2), indicated by their low inhibitory concentration for 50% (IC50) of parasite growth. The therapeutic potential of the active compounds was evaluated according to the selectivity index, which is a ratio of the cytotoxicity minimum lethal dose which eliminates 50% of cells and the in vitro IC50. Naphthoquinones 2 and 5, with activities similar to the reference antimalarial chloroquine, were also active against malaria in mice and suppressed parasitaemia by more than 60% in contrast to compound 11 which was inactive. Based on their in vitro and in vivo activities, compounds 2 and 5 are considered promising molecules for antimalarial treatment and warrant further study.

Topics: Animals; Antimalarials; Cell Line; Disease Models, Animal; Humans; Inhibitory Concentration 50; Malaria; Mice; Naphthoquinones; Parasitemia; Parasitic Sensitivity Tests; Phenazines; Plasmodium berghei; Plasmodium falciparum

To evaluate the therapeutic effect of hydroxynaphthoquinone mixture (HM) on dextran sulfate sodium (DSS)-induced colitis and explore the underlying mechanisms.. BALB/c mice received 3.5% DSS for 6 d to induce ulcerative colitis. Groups of mice were orally administered HM 3.5, 7 and 14 mg/kg and mesalazine 200 mg/kg per day for 7 d. During the experiment, clinical signs and body weight, stool consistency and visible fecal blood were monitored and recorded daily. A disease activity index score was calculated for each animal. At the conclusion of the experiment, the colonic histopathological lesions were evaluated. Myeloperoxidase (MPO) activity and tumor necrosis factor-α (TNF-α) levels were determined. Protein expression levels of TNF-α, nuclear factor-κB (NF-κB) p65, inhibitor of κB (IκB) and phosphorylation of IκB (p-IκB) were analyzed by Western blot analysis.. Administration of 3.5% DSS for 6 d successfully induced acute colitis associated with soft stool, diarrhea, rectal bleeding, and colon shortening, as well as a loss of body weight. Administration of HM effectively attenuated the severity of colonic mucosa injury. For histopathological analysis, HM treatment improved histological alterations and lowered pathological scores compared with the DSS only group. This manifested as a reduction in the extent of colon injury and inflammatory cell infiltration, as well as the degree of mucosal destruction. In addition, HM at doses of 7 and 14 mg/kg significantly decreased MPO activity in colonic tissue (0.98 ± 0.22 U/g vs 1.32 ± 0.24 U/g, 0.89 ± 0.37 U/g vs 1.32 ± 0.24 U/g tissue, P < 0.05) and serum TNF-α levels (68.78 ± 7.34 ng/L vs 88.98 ± 17.79 ng/L, 64.13 ± 14.13 ng/L vs 88.98 ± 17.79 ng/L, P < 0.05). Furthermore, HM down-regulated the expression of TNF-α, NF-κB p65 and p-IκBα in colonic tissue while up-regulating IκBα protein expression. These results suggest that the significant anti-inflammatory effect of HM may be attributable to its inhibition of TNF-α production and NF-κB activation.. HM had a favorable therapeutic effect on DSS-induced ulcerative colitis, supporting its further development and clinical application in inflammatory bowel disease.

Topics: Animals; Anti-Inflammatory Agents; Boraginaceae; Colitis, Ulcerative; Colon; Dextran Sulfate; Disease Models, Animal; Dose-Response Relationship, Drug; Gastrointestinal Agents; Inflammation Mediators; Mice, Inbred BALB C; Naphthoquinones; Phytotherapy; Plant Extracts; Plant Roots; Plants, Medicinal; Signal Transduction; Time Factors

Acyl-coenzyme A: cholesterol O-Acyltransferase (ACAT) and Acyl-coenzyme A: diacylglycerol O-acyltransferase (DGAT) enzymes play important roles in synthesizing neutral lipids, and inhibitors of these enzymes have been investigated as potential treatments for diabetes and other metabolic diseases. Administration of a Acyl-coenzyme A: diacylglycerol O-acyltransferase 1 (DGAT1) inhibitor with very limited cellular selectivity over ACAT resulted in significant adrenocortical degenerative changes in dogs. These changes included macrosteatotic vacuolation associated with adrenocyte cell death in the zonae glomerulosa and fasciculata and minimal to substantial mixed inflammatory cell infiltration and were similar to those described previously for some ACAT inhibitors in dogs. In the mouse, similar but only transient adrenocortical degenerative changes were seen as well as a distinctive nondegenerative reduction in cortical fine vacuolation. In the marmoset, only the distinctive nondegenerative reduction in cortical fine vacuolation was observed, suggesting that the dog, followed by the mouse, is the most sensitive species for cortical degeneration. Biochemical analysis of adrenal cholesterol and cholesteryl ester indicated that the distinctive reduction in cortical fine vacuolation correlated with a significant reduction in cholesteryl ester in the mouse and marmoset, whereas no significant reduction in cholestryl ester, but an increase in free cholesterol was observed in dogs. Administration of a DGAT1 inhibitor with markedly improved selectivity over ACAT to the marmoset and the mouse resulted in no adrenal pathology at exposures sufficient to cause substantial DGAT1 but not ACAT inhibition, thereby implicating ACAT rather than DGAT1 inhibition as the probable cause of the observed adrenal changes. Recognizing that the distinctive nondegenerative reduction in cortical fine vacuolation in the mouse could be used as a histopathological biomarker for an in vivo model of the more severe changes observed in dogs, the mouse has subsequently been used as a model to select DGAT1 inhibitors free of adrenocortical toxicity.

Topics: Adrenal Cortex; Animals; Callithrix; Cholesterol; Cholesterol Esters; Diacylglycerol O-Acyltransferase; Disease Models, Animal; Dogs; Female; Mice; Mice, Inbred C57BL; Naphthoquinones; Oxadiazoles; Photomicrography; Random Allocation; Sterol O-Acyltransferase

Praziquantel is the current drug of choice against schistosomiasis. The dependency on praziquantel exclusively is problematic, given the spread of the disease and the threat of drug resistance. This study investigates an alternative antischistosomal drug using the compound naphthoquine phosphate tablet, which is a novel single oral dose antimalarial drug, containing a combination of naphthoquine phosphate and artemisinin. In the present study, the therapeutic efficacies of different artemisinin-naphthoquine phosphate combination-dosing protocols were evaluated in experimentally infected mice harbouring juvenile or adult stages of Schistosoma mansoni (Egyptian strain). The study shows that the oral administration of artemisinin-naphthoquine phosphate combination in a single dose of 400 mg/kg on day 7 p.i. resulted in a significant worm burden reduction of 95.07%. When used at a dose of 600 mg/kg on day 21 p.i., all female worms were killed before depositing eggs, resulting in complete absence of eggs in hepatic and intestinal tissues. The same dose given on day 42 p.i. reduced total and female worm burdens by 93.36% and 94.17%, respectively. In addition, artemisinin-naphthoquine phosphate combination induced significant reductions of 80.18% and 76.73% in the hepatic and intestinal tissue egg loads, respectively. Artemisinin-naphthoquine phosphate combination also induced significant alterations in the oogram pattern with elevated levels of dead eggs. Antipathological activities were evident in the amelioration of hepatic granulomata. Our findings hold promise for the development of a novel antischistosomal drug using an artemisinin-naphthoquine phosphate combination. Further in vitro and in vivo studies should be launched to elucidate the possible mechanism/s of action and to study the effect of artemisinin-naphthoquine phosphate combination on other human schistosomes.

Topics: Administration, Oral; Animals; Anthelmintics; Artemisinins; Disease Models, Animal; Female; Histocytochemistry; Intestines; Liver; Mice; Mice, Inbred BALB C; Naphthoquinones; Parasite Egg Count; Parasite Load; Schistosoma mansoni; Schistosomiasis mansoni; Treatment Outcome

Shikonin, an analog of naphthoquinone pigments isolated from the root of Lithospermum erythrorhyzon, was recently reported to exert beneficial anti-inflammatory effects both in vivo and in vitro. The present study aimed to investigate the potential therapeutic effect of shikonin in a murine model of lipopolysaccharide (LPS)-induced acute lung injury (ALI). Dexamethasone was used as a positive control to evaluate the anti-inflammatory effect of shikonin in the study. Pretreatment with shikonin (intraperitoneal injection) significantly inhibited LPS-induced increases in the macrophage and neutrophil infiltration of lung tissues and markedly attenuated myeloperoxidase activity. Furthermore, shikonin significantly reduced the concentrations of TNF-α, IL-6 and IL-1β in bronchoalveolar lavage fluid induced by LPS. Compared with the LPS group, lung histopathologic changes were less pronounced in the shikonin-pretreated mice. Additionally, Western blotting results showed that shikonin efficiently decreased nuclear factor-kappaB (NF-κB) activation by inhibiting the degradation and phosphorylation of IκBα. These results suggest that shikonin exerts anti-inflammatory properties in LPS-mediated ALI, possibly through inhibition of the NF-κB signaling pathway, which mediates the expression of pro-inflammatory cytokines. Shikonin may be a potential agent for the prophylaxis of ALI.

Topics: Acute Lung Injury; Animals; Anti-Inflammatory Agents, Non-Steroidal; Bronchoalveolar Lavage Fluid; Cytokines; Disease Models, Animal; Lipopolysaccharides; Lithospermum; Lung; Male; Mice; Mice, Inbred BALB C; Naphthoquinones; NF-kappa B; Organ Size; Plant Roots; Signal Transduction

Plumbagin (1) is a naphthoquinone constituent of plants that have been used in traditional systems of medicine since ancient times. In the present study, the role of 1 was examined on the amelioration of ulcerative colitis, an inflammatory bowel disease that is not curable currently. Plumbagin was tested at a dose of 6-10 mg/kg body weight in acute and chronic disease models. Diseased mice receiving 1 at 8-10 mg/kg demonstrated a significant suppression of disease symptoms in both models. However, body weight loss was not restored in either of the models. Levels of proinflammatory cytokines (TNF-α, IFN-γ, and IL-17) were reduced significantly by 1 in mice suffering from chronic disease, while cytokine levels remained unaffected in mice with acute disease. However, the percentage of inflammatory (CD14+/CD16+) monocytes present in peripheral blood was significantly reduced by >3-fold (p < 0.05) in treatment groups relative to controls in the acute model. Histological evaluations exhibited the restoration of goblet cells, crypts, and the submucosa along with a significant reduction in monocyte aggregation in colon sections from mice receiving treatment with 1. Restoration in colon size was also observed in the treatment groups.

Topics: Animals; Colitis, Ulcerative; Colon; Cytokines; Disease Models, Animal; Interleukin-17; Male; Mice; Molecular Structure; Naphthoquinones; Tumor Necrosis Factor-alpha

Cellular immunotherapy frequently fails to induce sustained remissions in patients with multiple myeloma, indicating the ability of multiple myeloma cells to evade cellular immunity. Toward a better understanding and effective therapeutic modulation of multiple myeloma immune evasion mechanisms, we here investigated the role of the tumor microenvironment in rendering multiple myeloma cells resistant to the cytotoxic machinery of T cells.. Using a compartment-specific, bioluminescence imaging-based assay system, we measured the lysis of luciferase-transduced multiple myeloma cells by CD4(+) or CD8(+) CTLs in the presence versus absence of adherent accessory cells of the bone marrow microenvironment. We simultaneously determined the level of CTL activation by measuring the granzyme B release in culture supernatants.. Bone marrow stromal cells from patients with multiple myeloma and healthy individuals, as well as vascular endothelial cells, significantly inhibited the lysis of multiple myeloma cells in a cell-cell contact-dependent manner and without substantial T-cell suppression, thus showing the induction of a cell adhesion-mediated immune resistance (CAM-IR) against CTL lysis. Further analyses revealed that adhesion to accessory cells downregulated Fas and upregulated the caspase-3 inhibitor survivin in multiple myeloma cells. Reconstitution of Fas expression with bortezomib enhanced the CTL-mediated lysis of multiple myeloma cells. Repressing survivin with the small-molecule YM155 synergized with CTLs and abrogated CAM-IR in vitro and in vivo.. These results reveal the cell adhesion-mediated induction of apoptosis resistance as a novel immune escape mechanism and provide a rationale to improve the efficacy of cellular therapies by pharmacologic modulation of CAM-IR.

Topics: Animals; Antineoplastic Agents; Cell Adhesion; Cell Communication; Cell Line, Tumor; Combined Modality Therapy; Cytotoxicity, Immunologic; Disease Models, Animal; fas Receptor; Humans; Imidazoles; Immunomodulation; Immunotherapy, Adoptive; Mice; Multiple Myeloma; Naphthoquinones; T-Lymphocytes, Cytotoxic; Tumor Microenvironment; Xenograft Model Antitumor Assays

Merkel cell carcinoma (MCC) is a neuroendocrine skin cancer associated with high mortality. Merkel cell polyomavirus (MCV), discovered in 2008, is associated with ~80% of MCC. The MCV large tumor (LT) oncoprotein upregulates the cellular oncoprotein survivin through its conserved retinoblastoma protein-binding motif. We confirm here that YM155, a survivin suppressor, is cytotoxic to MCV-positive MCC cells in vitro at nanomolar levels. Mouse survival was significantly improved for NOD-Scid-Gamma mice treated with YM155 in a dose and duration dependent manner for 3 of 4 MCV-positive MCC xenografts. One MCV-positive MCC xenograft (MS-1) failed to significantly respond to YM155, which corresponds with in vitro dose-response activity. Combination treatment of YM155 with other chemotherapeutics resulted in additive but not synergistic cell killing of MCC cell lines in vitro. These results suggest that survivin targeting is a promising therapeutic approach for most but not all MCV-positive MCCs.

Topics: Animals; Antineoplastic Agents; Carcinoma, Merkel Cell; Cell Line, Tumor; Cell Survival; Cell Transformation, Viral; Disease Models, Animal; Female; Humans; Imidazoles; Inhibitor of Apoptosis Proteins; Merkel cell polyomavirus; Mice; Naphthoquinones; Neoplasm Metastasis; Polyomavirus Infections; Survivin; Tumor Burden; Tumor Virus Infections; Xenograft Model Antitumor Assays

This study was undertaken to evaluate possible antiallergic effects of an extract of pigments from green sea urchin (Strongylocentrotus droebachiensis) shells. Effects were studied on animal models - guinea pig ileum contraction, rabbit eyes allergic conjunctivitis, and rabbit local skin irritation. The extract significantly reduced, in a dose-dependent manner, the histamine-induced contractions of the isolated guinea pig ileum with ID50 =1.2 µg/mL (in equivalents of spinochrome B), had an inhibitory effect on the model of ocular allergic inflammation surpassing the reference drug olopatadine, and did not show any irritating effect in rabbits. The extract predominantly contained polyhydroxy-1,4-naphthoquinone which would be responsible for the pharmacological activity. The active compounds of the extract were evaluated in silico with molecular docking. Molecular docking into H1R receptor structures obtained from molecular dynamic simulations showed that all spinochrome derivatives bind to the receptor active site, but spinochrome monomers fit better to it. The results of the present study suggest possibilities for the development of new agents for treating allergic diseases on the base of pigments from sea urchins shells.

Topics: Animal Shells; Animals; Anti-Allergic Agents; Conjunctivitis, Allergic; Dibenzoxepins; Disease Models, Animal; Dose-Response Relationship, Drug; Guinea Pigs; Histamine; Ileum; Male; Molecular Docking Simulation; Naphthoquinones; Olopatadine Hydrochloride; Pigments, Biological; Rabbits; Skin; Strongylocentrotus

To evaluate the potential effectiveness of hydroxynaphthoquinone mixture (HM) in rats with 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis.. Colitis was induced by intracolonic administration of TNBS (80 mg/kg, dissolved in 50% ethanol). Rats were treated daily for 7 d with HM (2.5, 5, 10 mg/kg) and mesalazine 100 mg/kg 24 h after TNBS instillation. Disease progression was monitored daily by observation of clinical signs and body weight change. At the end of the experiment, macroscopic and histopathologic lesions of rats were scored, and myeloperoxidase (MPO) activity was determined. We also determined inflammatory cytokine tumor necrosis factor (TNF)-α level by ELISA, Western blotting and immunochemistry to explore the potential mechanisms of HM.. After intracolonic instillation of TNBS, animals developed colitis associated with soft stool, diarrhea and marked colonic destruction. Administration of HM significantly attenuated clinical and histopathologic severity of TNBS-induced colitis in a dose-dependent manner. It abrogated body weight loss, diarrhea and inflammation, decreased macroscopic damage score, and improved histological signs, with a significant reduction of inflammatory infiltration, ulcer size and the severity of goblet cell depletion (all P < 0.05 vs TNBS alone group). HM could reduce MPO activity. In addition, it also decreased serum TNF-α level and down-regulated TNF-α expression in colonic tissue. This reduction was statistically significant when the dose of HM was 10 mg/kg (P < 0.05 vs TNBS alone group), and the effect was comparable to that of mesalazine and showed no apparent adverse effect. The underlying mechanism may be associated with TNF-α inhibition.. These findings suggest that HM possesses favourable therapeutic action in TNBS-induced colitis, which provides direct pharmacological evidence for its clinical application.

Topics: Animals; Anti-Inflammatory Agents; Boraginaceae; Colitis, Ulcerative; Colon; Disease Models, Animal; Disease Progression; Dose-Response Relationship, Drug; Gastrointestinal Agents; Goblet Cells; Inflammation Mediators; Male; Mesalamine; Naphthoquinones; Peroxidase; Phytotherapy; Plant Extracts; Plants, Medicinal; Rats; Rats, Sprague-Dawley; Time Factors; Trinitrobenzenesulfonic Acid; Tumor Necrosis Factor-alpha

β-Lapachone is a naturally occurring quinine, originally isolated from the bark of the lapacho tree (Tabebuia avellanedae) which is currently being evaluated in clinical trials for the treatment of cancer. In addition, recent investigations suggest its potential application for treatment of inflammatory diseases. Multiple sclerosis (MS) is an autoimmune disorder characterized by CNS inflammation and demyelination. Reactive T cells including IL-17 and IFN-γ-secreting T cells are believed to initiate MS and the associated animal model system experimental autoimmune encephalomyelitis (EAE). IL-12 family cytokines secreted by peripheral dendritic cells (DCs) and CNS microglia are capable of modulating T-cell phenotypes. The present studies demonstrated that β-lapachone selectively inhibited the expression of IL-12 family cytokines including IL-12 and IL-23 by DCs and microglia, and reduced IL-17 production by CD4(+) T-cells indirectly through suppressing IL-23 expression by microglia. Importantly, our studies also demonstrated that β-lapachone ameliorated the development on EAE. β-Lapachone suppression of EAE was associated with decreased expression of mRNAs encoding IL-12 family cytokines, IL-23R and IL-17RA, and molecules important in Toll-like receptor signaling. Collectively, these studies suggest mechanisms by which β-lapachone suppresses EAE and suggest that β-lapachone may be effective in the treatment of inflammatory diseases such as MS.

Topics: Analysis of Variance; Animals; Animals, Newborn; Anti-Inflammatory Agents, Non-Steroidal; Bone Marrow Cells; CD4-Positive T-Lymphocytes; Cell Survival; Cells, Cultured; Cerebral Cortex; Cytokines; Dendritic Cells; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Interactions; Encephalomyelitis, Autoimmune, Experimental; Enzyme-Linked Immunosorbent Assay; Freund's Adjuvant; Mice; Mice, Inbred C57BL; Microglia; Myelin-Oligodendrocyte Glycoprotein; Naphthoquinones; Peptide Fragments; Polysaccharides; Severity of Illness Index; Spleen; Statistics, Nonparametric; Time Factors

Systemic sclerosis (SSc) is a connective tissue disorder characterized by skin and visceral fibrosis, microvascular damage, and autoimmunity. HOCl-induced mouse SSc is a murine model that mimics the main features of the human disease, especially the activation and hyperproliferation rate of skin fibroblasts. We demonstrate here the efficiency of a tellurium-based catalyst 2,3-bis(phenyltellanyl)naphthoquinone ((PHTE)(2)NQ) in the treatment of murine SSc, through its selective cytotoxic effects on activated SSc skin fibroblasts. SSc mice treated with (PHTE)(2)NQ displayed a significant decrease in lung and skin fibrosis and in alpha-smooth muscle actin (α-SMA) expression in the skin compared with untreated mouse SSc animals. Serum concentrations of advanced oxidation protein products, nitrate, and anti-DNA topoisomerase I autoantibodies were increased in SSc mice, but were significantly reduced in SSc mice treated with (PHTE)(2)NQ. To assess the mechanism of action of (PHTE)(2)NQ, the cytotoxic effect of (PHTE)(2)NQ was compared in normal fibroblasts and in mouse SSc skin fibroblasts. ROS production is higher in mouse SSc fibroblasts than in normal fibroblasts, and was still increased by (PHTE)(2)NQ to reach a lethal threshold and kill mouse SSc fibroblasts. Therefore, the effectiveness of (PHTE)(2)NQ in the treatment of mouse SSc seems to be linked to the selective pro-oxidative and cytotoxic effects of (PHTE)(2)NQ on hyperproliferative fibroblasts.

Topics: Actins; Animals; Autoantibodies; Cells, Cultured; Disease Models, Animal; DNA Topoisomerases, Type I; Female; Fibroblasts; Fibrosis; Glutathione; Hydrogen Peroxide; Hypochlorous Acid; In Vitro Techniques; Mice; Mice, Inbred BALB C; Naphthoquinones; Nitric Oxide; Organometallic Compounds; Reactive Oxygen Species; Scleroderma, Systemic; Skin; Tellurium

The objective of this study was to develop a novel liposomal formulation, containing phosphatidylserine (PS), of buparvaquone (BPQ) and to evaluate its in vivo effectiveness in Leishmania (L.) infantum chagasi-infected hamsters. The activity of BPQ was evaluated against both the promastigote forms of different Leishmania species and the intracellular amastigotes of L. (L.) infantum chagasi. Buparvaquone was entrapped in PS-liposomes (BPQ-PS-LP), and the drug was quantified by ultra-high-performance liquid chromatography. The treatment was quantified by detecting the RNA of the living amastigotes in the spleen and the liver by real-time PCR. In vitro assays with L. (L.) infantum chagasi intracellular amastigotes were performed in peritoneal macrophages for the evaluation of the 50% inhibitory concentration (IC(50)). BPQ-PS-LP at 0.33 mg/kg/day for eight consecutive days reduced the number of amastigotes by 89.4% (P<0.05) in the spleen and by 67.2% (P>0.05) in the liver, compared to 84.3% (P<0.05) and 99.7% (P<0.05), respectively, following Glucantime® treatment at 50 mg/kg/day. Free BPQ at 20 mg/kg/day failed to treat the hamsters when compared to the untreated group. BPQ was significantly (P<0.05) selective against L. (L.) infantum chagasi intracellular amastigotes, with an IC(50) value of 1.5 μM; no in vitro mammalian cytotoxicity could be detected. Other cutaneous species were also susceptible to BPQ, with IC(50) values in the range 1-4 μM. BPQ-PS-LP caused a significant reduction in the parasite burden at a 60-fold lower dose than did the free BPQ. These results show the potential of PS-liposome formulations for the successful targeted delivery of BPQ in visceral leishmaniasis.

Topics: Animals; Antiprotozoal Agents; Cell Line; Cells, Cultured; Cricetinae; Disease Models, Animal; Humans; Inhibitory Concentration 50; Leishmania infantum; Leishmaniasis, Visceral; Liposomes; Macaca mulatta; Macrophages, Peritoneal; Male; Mesocricetus; Mice; Mice, Inbred BALB C; Naphthoquinones; Phosphatidylserines

"Neurohormesis" refers to a response to a moderate level of stress that enhances the ability of the nervous systems to resist more severe stress that might be lethal or cause dysfunction or disease. Neurohormetic phytochemicals, such as, resveratrol, sulforaphane, curcumin, and catechins, protect neurons against injury and disease. Naphthoquinones, such as, juglone and plumbagin, induce robust hormetic stress responses. However, the possibility that subtoxic dose of 5,8-dihydroxy-1,4-naphthoquinone (naphthazarin) may protect against brain diseases via the activation of an adaptive stress response pathway in the brain has not been investigated. In this study, we examined the neurohormetic effect of a subtoxic dose of naphthazarin in a Parkinson's disease model. It was found that, under these conditions, naphthazarin enhanced movement ability, prevented loss of dopaminergic neurons, and attenuated neuroinflammation in a 1-methyl-4-phenyl-1,2,3,4-tetrahydropyridine-induced Parkinson's disease model. Furthermore, it was found that the neuroprotective effect of naphthazarin was mediated by the suppression of astroglial activation in response to 1-methyl-4-phenylpyridine treatment. In conclusion, we suggest that naphthazarin, in view of its hormetic effect on neuroprotection, be viewed as a potential treatment for Parkinson's disease and other neurodegenerative diseases associated with neuroinflammation.

Topics: Animals; Astrocytes; Blotting, Western; Cell Survival; Disease Models, Animal; Immunohistochemistry; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; Neurons; Neuroprotective Agents; Parkinsonian Disorders

Plumbagin (PL), 5-hydroxy-2-methyl-1,4-naphthoquinone, is a quinoid constituent isolated from the roots of the medicinal plant Plumbago zeylanica L. (also known as chitrak). PL has also been found in Juglans regia (English Walnut), Juglans cinerea (whitenut) and Juglans nigra (blacknut). The roots of P. zeylanica have been used in Indian and Chinese systems of medicine for more than 2500 years for the treatment of various types of ailments. We were the first to report that PL inhibits the growth and invasion of hormone refractory prostate cancer (PCa) cells [Aziz,M.H. et al. (2008) Plumbagin, a medicinal plant-derived naphthoquinone, is a novel inhibitor of the growth and invasion of hormone-refractory prostate cancer. Cancer Res., 68, 9024-9032.]. Now, we present that PL inhibits in vivo PCa development in the transgenic adenocarcinoma of mouse prostate (TRAMP). PL treatment (2 mg/kg body weight i.p. in 0.2 ml phosphate-buffered saline, 5 days a week) to FVB-TRAMP resulted in a significant (P < 0.01) decrease in prostate tumor size and urogenital apparatus weights at 13 and 20 weeks. Histopathological analysis revealed that PL treatment inhibited progression of prostatic intraepithelial neoplasia (PIN) to poorly differentiated carcinoma (PDC). No animal exhibited diffuse tumor formation in PL-treated group at 13 weeks, whereas 75% of the vehicle-treated mice elicited diffuse PIN and large PDC at this stage. At 20 weeks, 25% of the PL-treated animals demonstrated diffuse PIN and 75% developed small PDC, whereas 100% of the vehicle-treated mice showed large PDC. PL treatment inhibited expression of protein kinase C epsilon (PKCε), signal transducers and activators of transcription 3 phosphorylation, proliferating cell nuclear antigen and neuroendocrine markers (synaptophysin and chromogranin-A) in excised prostate tumor tissues. Taken together, these results further suggest PL could be a novel chemopreventive agent against PCa.

Topics: Adenocarcinoma; Animals; Anticarcinogenic Agents; Antigens, Polyomavirus Transforming; Chromogranin A; Disease Models, Animal; Male; Mice; Mice, Transgenic; Naphthoquinones; Phosphorylation; Proliferating Cell Nuclear Antigen; Prostatic Neoplasms; Protein Kinase C-epsilon; STAT3 Transcription Factor; Synaptophysin

Hypertension is one of the most common human diseases worldwide, and extensive research efforts are focused upon the identification and utilizing of novel therapeutic drug targets. Nitric oxide (NO) produced by endothelial NO synthase (eNOS) is an important regulator of blood pressure (BP). β-Lapachone (βL), a well-known substrate of NAD(P)H:quinone oxidoreductase (NQO1), increases the cellular NAD(+)/NADH ratio via the activation of NQO1. In this study, we evaluated whether βL-induced activation of NQO1 modulates BP in an animal model of hypertension.. Spontaneously hypertensive rats (SHR), primary human aortic endothelial cells (HAEC), and endothelial cell lines were used to investigate the hypotensive effect of βL and its mode of action. βL treatment stimulated endothelium-dependent vascular relaxation in response to acetylcholine in aorta of SHR and dramatically lowered BP in SHR, but the hypotensive effect was completely blocked by eNOS inhibition with ω-nitro-l-arginine methyl ester. Aortic eNOS phosphorylation and eNOS protein expression were significantly increased in βL-treated SHR. In vitro studies revealed that βL treatment elevated the intracellular NAD(+)/NADH ratio and concentration of free Ca(2+) ([Ca(2+)]i), and resulted in Akt/AMP-activated protein kinase/eNOS activation. These effects were abolished by NQO1 siRNA and [Ca(2+)]i inhibition through a ryanodine receptor blockade.. This study is the first to demonstrate that NQO1 activation has a hypotensive effect mediated by eNOS activation via cellular NAD(+)/NADH ratio modulation in an animal model. These results provide strong evidence suggesting NQO1 might be a new therapeutic target for hypertension.

Topics: Acetylcholine; AMP-Activated Protein Kinases; Animals; Antihypertensive Agents; Blood Pressure; Calcium; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Endothelial Cells; Enzyme Activation; Enzyme Activators; Enzyme Inhibitors; Humans; Hypertension; Male; Mice; NAD; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; NG-Nitroarginine Methyl Ester; Nitric Oxide Synthase Type III; Phosphatidylinositol 3-Kinase; Proto-Oncogene Proteins c-akt; Rats; Rats, Inbred SHR; RNA Interference; Time Factors; Transfection; Vasodilation; Vasodilator Agents

This paper describes the antileishmanial properties of LQB-118, a new compound designed by molecular hybridization, orally active in Leishmania amazonensis-infected BALB/c mice.. In vitro antileishmanial activity was determined in L. amazonensis-infected macrophages. For in vivo studies, LQB-118 was administered intralesionally (15 μg/kg/day, five times a week), intraperitoneally (4.5 mg/kg/day, five times a week) or orally (4.5 mg/kg/day, five times a week) to L. amazonensis-infected BALB/c mice throughout experiments lasting 85 or 105 days. At the end of the experiments, serum levels of alanine aminotransferase, aspartate aminotransferase and creatinine were measured as toxicological parameters.. LQB-118 was active against intracellular amastigotes of L. amazonensis [50% inhibitory concentration (IC(50)) 1.4 μM] and significantly less so against macrophages (IC(50) 18.5 μM). LQB-118 administered intralesionally, intraperitoneally or orally was found to control both lesion and parasite growth in L. amazonensis-infected BALB/c mice, without altering serological markers of toxicity.. These results demonstrate that the molecular hybridization of a naphthoquinone core to pterocarpan yielded a novel antileishmanial compound that was locally and orally active in an experimental cutaneous leishmaniasis model.

Topics: Administration, Oral; Administration, Topical; Alanine Transaminase; Animals; Antiprotozoal Agents; Aspartate Aminotransferases; Chemical and Drug Induced Liver Injury; Creatinine; Disease Models, Animal; Inhibitory Concentration 50; Leishmania mexicana; Leishmaniasis, Cutaneous; Liver; Mice; Mice, Inbred BALB C; Naphthoquinones; Pterocarpans; Rodent Diseases; Serum; Treatment Outcome

Organotellurides are newly described redox-catalyst molecules with original pro-oxidative properties. We have investigated the in vitro and in vivo antitumoral effects of the organotelluride catalyst LAB027 in a mouse model of colon cancer and determined its profile of toxicity in vivo. LAB027 induced an overproduction of H(2)O(2) by both human HT29 and murine CT26 colon cancer cell lines in vitro. This oxidative stress was associated with a decrease in proliferation and survival rates of the two cell lines. LAB027 triggered a caspase-independent, ROS-mediated cell death by necrosis associated with mitochondrial damages and autophagy. LAB027 also synergized with the cytotoxic drug oxaliplatin to augment its cytostatic and cytotoxic effects on colon cancer cell lines but not on normal fibroblasts. The opposite effects of LAB027 on tumor and on non-transformed cells were linked to differences in the modulation of reduced glutathione metabolism between the two types of cells. In mice grafted with CT26 tumor cells, LAB027 alone decreased tumor growth compared with untreated mice, and synergized with oxaliplatin to further decrease tumor development compared with mice treated with oxaliplatin alone. LAB027 an organotelluride catalyst compound synergized with oxaliplatin to prevent both in vitro and in vivo colon cancer cell proliferation while decreasing the in vivo toxicity of oxaliplatin. No in vivo adverse effect of LAB027 was observed in this model.

Topics: Animals; Antineoplastic Agents; Apoptosis; Caspases; Catalysis; Cell Line, Tumor; Cell Proliferation; Colonic Neoplasms; Disease Models, Animal; Glutathione; Humans; Hydrogen Peroxide; Mice; Naphthoquinones; Organometallic Compounds; Organoplatinum Compounds; Oxaliplatin; Oxidation-Reduction; Oxidative Stress; Tellurium; Transplantation, Heterologous

Many phytochemicals function as noxious agents that protect plants against insects and other damaging organisms. However, at subtoxic doses, the same phytochemicals may activate adaptive cellular stress response pathways that can protect cells against a variety of adverse conditions. We screened a panel of botanical pesticides using cultured human and rodent neuronal cell models, and identified plumbagin as a novel potent activator of the nuclear factor E2-related factor 2 (Nrf2)/antioxidant response element (ARE) pathway. In vitro, plumbagin increases nuclear localization and transcriptional activity of Nrf2, and induces the expression of the Nrf2/ARE-dependent genes, such as heme oxygenase 1 in human neuroblastoma cells. Plumbagin specifically activates the Nrf2/ARE pathway in primary mixed cultures from ARE-human placental alkaline phosphatase reporter mice. Exposure of neuroblastoma cells and primary cortical neurons to plumbagin provides protection against subsequent oxidative and metabolic insults. The neuroprotective effects of plumbagin are abolished by RNA interference-mediated knockdown of Nrf2 expression. In vivo, administration of plumbagin significantly reduces the amount of brain damage and ameliorates-associated neurological deficits in a mouse model of focal ischemic stroke. Our findings establish precedence for the identification and characterization of neuroprotective phytochemicals based upon their ability to activate adaptive cellular stress response pathways.

Topics: Animals; Cell Line, Tumor; Cell Survival; Cells, Cultured; Cerebral Cortex; Cerebral Infarction; Disease Models, Animal; Embryo, Mammalian; Gene Expression Regulation; Glucose; Heme Oxygenase-1; Humans; Hypoxia; Infarction, Middle Cerebral Artery; Mice; Mice, Inbred C57BL; Naphthoquinones; Neuroblastoma; Neurologic Examination; Neurons; Neuroprotective Agents; NF-E2-Related Factor 2; Oxidative Stress; Rats; Rats, Sprague-Dawley; Transcription Factor AP-1; Transfection

In the present paper we studied the effect of shikonin on ear oedema induced by 12-O-tetradecanoylphorbol-13-acetate (TPA), and determined the mechanisms through which shikonin might exert its topical anti-inflammatory action.. Acute ear oedema was induced in mice by topical application of TPA. The in vitro assays used macrophages RAW 264.7 cells stimulated with lipopolysaccharide. Cyclooxygenase-2, inducible nitric oxide synthase, protein kinase Calpha, extracellular signal-regulated protein kinase (ERK), phosphorylated ERK (pERK), c-Jun N-terminal kinase (JNK), pJNK, p38, p-p38, p65, p-p65, inhibitor protein of nuclear factor-kappaB (NF-kappaB) (IkappaBalpha) and pIkappaBalpha were measured by Western blotting, activation and binding of NF-kappaB to DNA was detected by reporter gene and electrophoretic mobility shift assay, respectively, and NF-kappaB p65 localization was detected by immunocytochemistry.. Shikonin reduced the oedema (inhibitory dose 50 = 1.0 mg per ear), the expression of cyclooxygenase-2 (70%) and of inducible nitric oxide synthase (100%) in vivo. It significantly decreased TPA-induced translocation of protein kinase Calpha, the phosphorylation and activation of ERK, the nuclear translocation of NF-kappaB and the TPA-induced NF-kappaB-DNA-binding activity in mouse skin. Moreover, in RAW 264.7 cells, shikonin significantly inhibited the binding of NF-kappaB to DNA in a dose-dependent manner and the nuclear translocation of p65.. Shikonin exerted its topical anti-inflammatory action by interfering with the degradation of IkappaBalpha, thus inhibiting the activation of NF-kappaB.

Topics: Administration, Topical; Animals; Anti-Inflammatory Agents, Non-Steroidal; Cell Line; Cell Nucleus; Disease Models, Animal; Dose-Response Relationship, Drug; Edema; Female; I-kappa B Proteins; Inflammation; Inhibitory Concentration 50; Macrophages; Mice; Naphthoquinones; NF-kappa B; NF-KappaB Inhibitor alpha; Phosphorylation; Protein Transport; Tetradecanoylphorbol Acetate

Chagas disease, caused by Trypanosoma cruzi, is a widespread infection in Latin America. Currently, only 2 partially effective and highly toxic drugs, i.e., benznidazole and nifurtimox, are available for the treatment of this disease, and several efforts are underway in the search for better chemotherapeutic agents. Here, we have determined the trypanocidal activity of 2,3-diphenyl-1 ,4-naphthoquinone (DPNQ), a novel quinone derivative. In vitro, DPNQ was highly cytotoxic at a low, micromolar concentration (LD50 = 2.5 microM) against epimastigote, cell-derived trypomastigote, and intracellular amastigote forms of T. cruzi, but not against mammalian cells (LD50 = 130 microM). In vivo studies on the murine model of Chagas disease revealed that DPNQ-treated animals (3 doses of 10 mg/kg/day) showed a significant delay in parasitemia peak and higher (up to 60%) survival rate 70 days post-infection, when compared with the control group (infected, untreated). We also observed a 2-fold decrease in parasitemia between the control group (infected, untreated) and the treated group (infected, treated). No apparent drug toxicity effects were noticed in the control group (uninfected, treated). In addition, we determined that DPNQ is the first competitive inhibitor of T. cruzi lipoamide dehydrogenase (TcLipDH) thus far described. Our results indicate that DPNQ is a promising chemotherapeutic agent against T. cruzi.

Topics: Animals; Cell Line; Chagas Disease; Dihydrolipoamide Dehydrogenase; Disease Models, Animal; Enzyme Inhibitors; Female; Lethal Dose 50; Mice; Mice, Inbred C3H; Naphthoquinones; Trypanocidal Agents; Trypanosoma cruzi

Nicotinamide adenine dinucleotides (NAD+ and NADH) play a crucial role in cellular energy metabolism, and a dysregulated NAD+-to-NADH ratio is implicated in metabolic syndrome. However, it is still unknown whether a modulating intracellular NAD+-to-NADH ratio is beneficial in treating metabolic syndrome. We tried to determine whether pharmacological stimulation of NADH oxidation provides therapeutic effects in rodent models of metabolic syndrome.. We used beta-lapachone (betaL), a natural substrate of NADH:quinone oxidoreductase 1 (NQO1), to stimulate NADH oxidation. The betaL-induced pharmacological effect on cellular energy metabolism was evaluated in cells derived from NQO1-deficient mice. In vivo therapeutic effects of betaL on metabolic syndrome were examined in diet-induced obesity (DIO) and ob/ob mice.. NQO1-dependent NADH oxidation by betaL strongly provoked mitochondrial fatty acid oxidation in vitro and in vivo. These effects were accompanied by activation of AMP-activated protein kinase and carnitine palmitoyltransferase and suppression of acetyl-coenzyme A (CoA) carboxylase activity. Consistently, systemic betaL administration in rodent models of metabolic syndrome dramatically ameliorated their key symptoms such as increased adiposity, glucose intolerance, dyslipidemia, and fatty liver. The treated mice also showed higher expressions of the genes related to mitochondrial energy metabolism (PPARgamma coactivator-1alpha, nuclear respiratory factor-1) and caloric restriction (Sirt1) consistent with the increased mitochondrial biogenesis and energy expenditure.. Pharmacological activation of NADH oxidation by NQO1 resolves obesity and related phenotypes in mice, opening the possibility that it may provide the basis for a new therapy for the treatment of metabolic syndrome.

Topics: Adenylate Kinase; Animals; Disease Models, Animal; Energy Metabolism; Metabolic Syndrome; Mice; Mice, Knockout; NAD; NAD(P)H Dehydrogenase (Quinone); NADPH Dehydrogenase; Naphthoquinones; Obesity; Oxidation-Reduction; Phenotype; Signal Transduction

Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are important pathogenic mechanisms in atherosclerosis and restenosis after vascular injury. In this study, we investigated the effects of beta-lapachone (betaL) (3,4-Dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione), which is a potent antitumor agent that stimulates NAD(P)H:quinone oxidoreductase (NQO)1 activity, on neointimal formation in animals given vascular injury and on the proliferation of VSMCs cultured in vitro. betaL significantly reduced the neointimal formation induced by balloon injury. betaL also dose-dependently inhibited the FCS- or platelet-derived growth factor-induced proliferation of VSMCs by inhibiting G(1)/S phase transition. betaL increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase 1 in rat and human VSMCs. Chemical inhibitors of AMPK or dominant-negative AMPK blocked the betaL-induced suppression of cell proliferation and the G(1) cell cycle arrest, in vitro and in vivo. The activation of AMPK in VSMCs by betaL is mediated by LKB1 in the presence of NQO1. Taken together, these results show that betaL inhibits VSMCs proliferation via the NQO1 and LKB1-dependent activation of AMPK. These observations provide the molecular basis that pharmacological stimulation of NQO1 activity is a new therapy for the treatment of vascular restenosis and/or atherosclerosis which are caused by proliferation of VSMCs.

Topics: Acetyl-CoA Carboxylase; AMP-Activated Protein Kinase Kinases; AMP-Activated Protein Kinases; Animals; Carotid Artery Injuries; Carotid Stenosis; Cell Cycle; Cell Proliferation; Cyclin-Dependent Kinase Inhibitor p21; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme Activation; Enzyme Activators; Enzyme Inhibitors; HeLa Cells; Humans; Hyperplasia; Male; Muscle, Smooth, Vascular; Myocytes, Smooth Muscle; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Phosphorylation; Platelet-Derived Growth Factor; Protein Serine-Threonine Kinases; Rats; Rats, Sprague-Dawley; Retinoblastoma Protein; RNA Interference; RNA, Small Interfering; Secondary Prevention; Time Factors; Tumor Suppressor Protein p53; Tunica Intima

Human tissue transglutaminase (TGM2) is a calcium-dependent crosslinking enzyme involved in the posttranslational modification of intra- and extracellular proteins and implicated in several neurodegenerative diseases. To find specific inhibitors to TGM2, two structurally diverse chemical libraries (LOPAC and Prestwick) were screened. We found that ZM39923, a Janus kinase inhibitor, and its metabolite ZM449829 were the most potent inhibitors with IC(50) of 10 and 5 nM, respectively. In addition, two other inhibitors, including tyrphostin 47 and vitamin K(3), were found to have an IC(50) in the micromolar range. These agents used in part a thiol-dependent mechanism to inhibit TGM2, consistent with the activation of TGM2 by reduction of an intramolecular disulfide bond. These inhibitors were tested in a polyglutamine-expressing Drosophila model of neurodegeneration and found to improve survival. The TGM2 inhibitors we discovered may serve as valuable lead compounds for the development of orally active TGM2 inhibitors to treat human diseases.

Topics: Animals; Calcium; Combinatorial Chemistry Techniques; Disease Models, Animal; Drosophila melanogaster; Drug Evaluation, Preclinical; Enzyme Inhibitors; Factor XIIIa; GTP-Binding Proteins; Guanosine Triphosphate; Humans; Machado-Joseph Disease; Molecular Structure; Naphthoquinones; Octoxynol; Protein Glutamine gamma Glutamyltransferase 2; Transglutaminases; Tyrphostins

Indoleamine 2,3-dioxygenase (IDO) is emerging as an important new therapeutic target for the treatment of cancer, chronic viral infections, and other diseases characterized by pathological immune suppression. While small molecule inhibitors of IDO exist, there remains a dearth of high-potency compounds offering in vivo efficacy and clinical translational potential. In this study, we address this gap by defining a new class of naphthoquinone-based IDO inhibitors exemplified by the natural product menadione, which is shown in mouse tumor models to have similar antitumor activity to previously characterized IDO inhibitors. Genetic validation that IDO is the critical in vivo target is demonstrated using IDO-null mice. Elaboration of menadione to a pyranonaphthoquinone has yielded low nanomolar potency inhibitors, including new compounds which are the most potent reported to date (K(i) = 61-70 nM). Synthetic accessibility of this class will facilitate preclinical chemical-genetic studies as well as further optimization of pharmacological parameters for clinical translation.

Topics: Animals; Antineoplastic Agents; Binding Sites; Cell Proliferation; Cell Survival; Computer Simulation; Crystallography, X-Ray; Disease Models, Animal; Dose-Response Relationship, Drug; Drug Screening Assays, Antitumor; Enzyme Inhibitors; Indoleamine-Pyrrole 2,3,-Dioxygenase; Mice; Mice, Knockout; Mice, Nude; Models, Molecular; Molecular Structure; Naphthoquinones; Pyrones; Stereoisomerism; Structure-Activity Relationship; Vitamin K 3

Allergen-induced airways oedema in actively sensitized rats has been studied earlier by magnetic resonance imaging (MRI). We used MRI to follow the consequences of non-immunological mast cell activation induced by compound 48/80 in the rat lungs in vivo.. Male naïve rats were scanned by MRI prior to and at several time points following intratracheal administration of the mast cell secretagogue, compound 48/80. The effects of a range of drugs on the response induced by compound 48/80 were studied.. Strong fluid signals were detected by MRI in the lungs at 24 h after compound 48/80, correlating with increased protein concentration and inflammatory cell infiltration in bronchoalveolar lavage, and with perivascular oedema observed histologically. Pharmacological intervention demonstrated that the increase in MRI signal volume induced by compound 48/80 24 h after challenge was blocked by disodium cromoglycate and the glucocorticoid, budesonide. Pretreatment with wortmannin, capsazepine, DNK333 (a dual neurokinin (NK) 1 and NK2 antagonist) or the anti-allergy drug CGS8515, but not indomethacin, resulted in partial inhibition.. Compound 48/80 induced a complex inflammatory reaction which did not solely involve mast cell degranulation but also activation of sensory nerves and was qualitatively similar to allergen challenge. Changes observed by MRI correlated with decreases in protein concentration in BAL fluid. However, the magnitude of the changes detected was greater using MRI. Our results demonstrate that MRI is a sensitive and efficient tool to assess the effects of drugs on lung inflammation.

Topics: Androstadienes; Animals; Anti-Inflammatory Agents; Aza Compounds; Benzamides; Bronchoalveolar Lavage Fluid; Budesonide; Capsaicin; Cell Degranulation; Cromolyn Sodium; Disease Models, Animal; Drug Evaluation, Preclinical; Indomethacin; Lung; Magnetic Resonance Imaging; Male; Mast Cells; Naphthoquinones; ortho-Aminobenzoates; p-Methoxy-N-methylphenethylamine; Proteins; Pulmonary Edema; Rats; Rats, Inbred BN; Respiratory System Agents; Time Factors; Wortmannin

Derivatisation of diospyrin, a bisnaphthoquinonoid isolated from Diospyros montana Roxb., led to the modification of its inhibitory activity, in vitro, towards a murine tumour model, Ehrlich ascites carcinoma (EAC), and two human cancer cell lines, viz., malignant skin melanoma (A375) and epidermoid laryngeal carcinoma (Hep2). Among the novel derivatives, an epoxide exhibited the maximum antiproliferative activity (IC(50) values in the range of 0.03-0.21 microM) and a comparatively lower toxicity (IC(50) approximately 98 microM) in normal human peripheral blood mononuclear cells (PBMC). This compound might provide a novel 'lead' for the development of clinically effective antiproliferative agents against cancer.

Topics: Animals; Antineoplastic Agents; Cell Proliferation; Diospyros; Disease Models, Animal; Humans; Inhibitory Concentration 50; Leukocytes, Mononuclear; Mice; Naphthoquinones; Plant Bark; Tumor Cells, Cultured

The mouse-virulent RH strain of Toxoplasma gondii is generally considered to have lost its cyst-forming capacity, and conversion of RH tachyzoites into cysts in non-immune mice has previously been shown exclusively following early treatment with sulfadiazine (SDZ). We here describe the development of tissue cysts in mice infected with RH strain parasites and treated with atovaquone (ATO) combined with pyrrolidine dithiocarbamate (PDTC). Groups of Swiss-Webster mice infected intraperitoneally (i.p.) with 10(2) RH tachyzoites were treated with 5, 25 and 100 mg of ATO/kg per day alone or combined with PDTC at 250 mg/kg per day from day 1 postinfection (p.i.) for 14 days. A total of 19 mice survived the 6-week observation period. Of these, brain cysts were recovered in nine (47%), with burdens ranging from 50 to 3120 (mean +/- S.D. = 622 +/- 963). All cyst-harboring mice had high specific IgG antibody levels (1:10,240-1:40,960, corresponding to 500-2000 IU/ml), as did one mouse in which cysts were not demonstrated, which was therefore included in the group of mice with residual infection. Bioassay performed to test the infectivity of these cysts produced acute lethal toxoplasmosis following i.p. inoculation in all instances (100%), and importantly, following peroral inoculation in four (29%). The recovered tachyzoites were highly infectious. In addition, significantly elevated interferon gamma (IFN-gamma) in the treated mice which developed residual infection compared with any group of infection-free (treated or subinoculated) mice, indicates immunological control of the parasite in the latent form. In conclusion, early treatment of mice infected with T. gondii RH tachyzoites with ATO and PDTC induces conversion into tissue cysts, thus providing a new model for studying the mechanism(s) of T. gondii stage conversion.

Topics: Animals; Antiprotozoal Agents; Atovaquone; Brain; Disease Models, Animal; Drug Administration Schedule; Drug Therapy, Combination; Female; Mice; Naphthoquinones; Oocysts; Pyrrolidines; Thiocarbamates; Toxoplasma; Toxoplasmosis

Presented are the results of the use of histochrome in animals with experimental hemorrhagic stroke. An influence of the compound on cerebral edema and the dynamics of hemoglobulin converting as well as a role of MRT in diagnostic of experimental hemorrhagic stroke in different periods of the disease are discussed.

Topics: Animals; Cerebral Hemorrhage; Disease Models, Animal; Follow-Up Studies; Magnetic Resonance Imaging; Male; Motor Activity; Naphthoquinones; Rats; Rats, Wistar; Severity of Illness Index; Treatment Outcome

DA-11004 is a synthetic, potent NADP-dependent isocitrate dehydrogenase (IDPc) inhibitor where IC50 for IDPc is 1.49 microM. The purpose of this study was to evaluate the effects of DA-11004 on the high fat high sucrose (HF)-induced obesity in male C57BL/6J mice. After completing a 8-week period of experimentation, the mice were sacrificed 1 hr after the last DA-11004 treatment and their blood, liver, and adipose tissues (epididymal and retroperitoneal fat) were collected. There was a significant difference in the pattern of increasing body weight between the HF control and the DA-11004 group. In the DA-11004 (100 mg/kg) treated group the increase in body weight significantly declined and a content of epididymal fat and retroperitoneal fat was also significantly decreased as opposed to the HF control. DA-11004 (100 mg/ kg) inhibited the IDPc activity, and thus, NADPH levels in plasma and the levels of free fatty acid (FFA) or glucose in plasma were less than the levels of the HF control group. In conclusion, DA-11004 inhibited the fatty acid synthesis in adipose tissues via IDPc inhibition, and it decreased the plasma glucose levels and FFA in HF diet-induced obesity of C57BL/6J mice.

Topics: Adipose Tissue; Animals; Blood Glucose; Body Weight; Diabetes Mellitus, Experimental; Dietary Fats; Dietary Sucrose; Disease Models, Animal; Drug Evaluation, Preclinical; Epididymis; Fatty Acids, Nonesterified; Hypoglycemic Agents; Isocitrate Dehydrogenase; Liver; Male; Mice; Mice, Inbred C57BL; Mice, Obese; Naphthoquinones; Peritoneum; Time Factors; Triglycerides

The indolequinone compound EO9 has good pharmacodynamic properties in terms of bioreductive activation and selectivity for either NAD(P)H:quinone oxidoreductase-1 (NQO1)-rich aerobic or NQO1-deficient hypoxic cells. However, its pharmacokinetic properties are poor and this fact is believed to be a major reason for EO9's lack of clinical efficacy. The purpose of this study was to develop quinone-based bioreductive drugs that retained EO9's good properties, in terms of bioreductive activation, but have improved pharmacokinetic properties. Out of 11 naphthoquinone compounds evaluated, 2-aziridinyl-5-hydroxy-1,4-naphthoquinone (compound 2), 2,3-bis(aziridinyl)-5-hydroxy-1,4-naphthoquinone (compound 3), and 2-aziridinyl-6-hydroxymethyl-1,4-naphthoquinone (compound 11) were selected for further evaluation based on good substrate specificity for NQO1 and selectivity towards NQO1-rich cells in vitro. Compound 3 was of particular interest as it also demonstrated selectivity for NQO1-rich cells under hypoxic conditions. Compound 3 was not metabolised by murine whole blood in vitro (in contrast to compounds 2, 11 and EO9) and pharmacokinetic studies in non-tumour-bearing mice in vivo (at the maximum soluble dose of 60 mg kg(-1) administered intraperitoneally) demonstrated significant improvements in plasma half-life (16.2 min) and AUC values (22.5 microM h) compared to EO9 (T(1/2) = 1.8 min, AUC = 0.184 microM h). Compound 3 also demonstrated significant anti-tumour activity against H460 and HCT-116 human tumour xenografts in vivo, whereas EO9 was inactive against these tumours. In conclusion, compound 3 is a promising lead compound that may target both aerobic and hypoxic fractions of NQO1-rich tumours and further studies to elucidate its mechanism of action and improve solubility are warranted.

Topics: Animals; Antineoplastic Agents; Aziridines; Disease Models, Animal; Drug Screening Assays, Antitumor; Drug Stability; Female; Humans; Hypoxia; Indolequinones; Mice; NAD(P)H Dehydrogenase (Quinone); Naphthoquinones; Neoplasm Transplantation; Neoplasms, Experimental; Substrate Specificity; Tumor Cells, Cultured; Xenograft Model Antitumor Assays

beta-Lapachone, a 1,2-naphthoquinone, is a novel chemotherapeutic agent. It has been shown to be capable of suppressing inducible nitric oxide synthase expression and function in rat alveolar macrophages. The authors further performed experiments to examine the molecular mechanism of beta-lapachone on LPS-induced responses in rat alveolar macrophages and to evaluate its in vivo antiinflammatory effect. A significant increase in nitrite production and inducible nitric oxide synthase expression was elicited in macrophages treated with LPS that was inhibited by coincubation with beta-lapachone. beta-Lapachone could also inhibit the production of tumor necrosis factor-alpha induced by LPS. LPS induces protein tyrosine phosphorylation and nuclear factor-kappaB binding activity by gel mobility shift assay in macrophages. These events were significantly inhibited by beta-lapachone. Furthermore, beta-lapachone in vivo protected against the induction of lung edema, lung-inducible nitric oxide synthase protein expression and nuclear factor-kappaB activation, lethality, and increased plasma nitrite and serum tumor necrosis factor-alpha levels induced by LPS. These results indicate that beta-lapachone suppresses inducible nitric oxide synthase induction and tumor necrosis factor-alpha production mediated by the inhibition of protein tyrosine phosphorylation and nuclear factor-kappaB activation caused by LPS. This results in a beneficial effect in an animal model of sepsis.

Topics: Animals; Anti-Infective Agents; Cells, Cultured; Disease Models, Animal; Drug Evaluation, Preclinical; Endotoxins; Inflammation; Lipopolysaccharides; Macrophage Activation; Macrophages, Alveolar; Mice; Mice, Inbred BALB C; Mitogen-Activated Protein Kinases; Naphthoquinones; NF-kappa B; Nitric Oxide Synthase; Phosphorylation; Pulmonary Edema; Rats; Sepsis; Signal Transduction; Tumor Necrosis Factor-alpha

The effect of 14 natural and synthetic naphthoquinones in the replication of Toxoplasma gondii was evaluated. In vitro studies were accomplished in cultures of 2C4 fibroblasts infected with RH-strain. Enzyme-linked immunosorbent assay was used to quantify parasite growth. For the studies in vivo, mice were infected with tachyzoites of the RH strain or cysts of the T. gondii EGS strain. In vitro, seven naphthoquinones demonstrated significant inhibition of intracellular T. gondii growth at concentrations of 1 and 5 micrograms/ml. Only three compounds were significantly protective when tested in animals: 2-hydroxy-3'-(3'-pentenyl)-1,4-naphthoquinone (PHNQ4), 2-hydroxy-3-(1'-vinylphenyl)-1,4-naphthoquinone (PHNQ5), and 2-hydroxy-3-(1'-propen-3'-phenyl)-1,4-naphthoquinone (PHNQ6). In animals infected with the EGS strain and treated with PHNQ4 (50 mg/kg/day orally), a 7-day prolongation of the time to death was observed. Treatment with 100 mg/kg/day orally or 50 mg/kg/day i.p. of PHNQ5 resulted in a 5-day and 16-day prolongation of the time to death, respectively. Treatment with 50 mg/kg/day orally or 50 mg/kg/day i.p. of PHNQ6 resulted in a 4-day prolongation of the time to death or up to 30 days after treatment, respectively. Our results suggest that the naphthoquinones may be important therapeutic agents for the treatment of toxoplasmosis.

Topics: Animals; Antiprotozoal Agents; Disease Models, Animal; Dose-Response Relationship, Drug; Enzyme-Linked Immunosorbent Assay; Female; Fibroblasts; Humans; Mice; Naphthoquinones; Toxoplasma; Toxoplasmosis, Animal

The efficacy of atovaquone (ATO) combined with clindamycin (CLI) against Toxoplasma gondii was examined in murine models of infection with a mouse-non-virulent (Me49) strain. Swiss-Webster mice inoculated by mouth with 10 or 20 cysts were treated with ATO and CLI alone or combined at dosages of ATO 5-100 and CLI 25-400 mg/kg/day for 2-4 weeks. Drug treatment was initiated (i) day 4 post-infection (acute infection), (ii) 3 months post-infection (chronic infection) and (iii) following a 2-3 week course of treatment with dexamethasone (DXM) alone or combined with cortisone-acetate (CA) introduced 3 months post-infection (reactivated toxoplasmosis). In acute infection, whereas treatment with any drug or drug combination significantly enhanced survival and reduced the brain cyst burden, in mice treated with ATO alone or combined with CLI, the cyst counts were significantly lower than in mice treated with CLI alone. In chronic infection, the decrease in the cyst burden observed 2 weeks after treatment with either drug alone was significant only in mice treated with the combined drugs. Most importantly, in reactivated toxoplasmosis, whereas an effect for the combined drugs was shown in mice suppressed with both DXM alone and combined with CA, in mice pre-treated with DXM a 3 week course of ATO > or = 25 and CLI 50 mg/kg/day significantly increased survival and markedly decreased the cyst burden. The latter effect was long-term, since the cyst burdens in treated mice continued to decrease up to 3 months later, whereas they increased in the untreated mice. The results warrant clinical evaluation of the combination of ATO and CLI in the treatment of toxoplasmosis in both immunocompetent and, more importantly, immunosuppressed patients.

Topics: Acute Disease; Animals; Atovaquone; Brain; Clindamycin; Cysts; Disease Models, Animal; Drug Therapy, Combination; Female; Mice; Naphthoquinones; Toxoplasma; Toxoplasmosis, Animal

The hollow fiber test has been developed for the preliminary in vivo assessment of cancer chemotherapeutic efficacy of selected natural products. Using this model, we have established growth conditions for HL-60, HUVEC, Ishikawa, KB, KB-V1, LNCaP, Lu1, MCF-7, Mel2, P-388, and SW626 cells implanted at the intraperitoneal (i.p.) and subcutaneous (s.c.) compartments of athymic mice. Five cytotoxic natural product isolates (2-6) were tested in this model, along with paclitaxel (taxol) (1). Among the compounds tested, dioscin (2) and 13-methoxy-15-oxozoapatlin (3) were found to be active, indicating their potential to function as cancer chemotherapeutic agents. On the other hand, ochraceolide A (4), alpha-lapachone (5), and 2-(1-hydroxyethyl)naphtha[2,3-b]furan-4,9-quinone (6), all of which were significantly cytotoxic to cultured mammalian cells, did not mediate significant responses with the hollow fiber model. In further xenograft studies using KB cells implanted at the subcutaneous site, compound 3 mediated a statistically significant response which was consistent with the response observed at the subcutaneous compartment in the hollow fiber tests. In sum, these studies illustrate the usefulness of the hollow fiber model in natural product drug discovery programs. Preliminary indications of potential therapeutic efficacy can be provided quickly at relatively low expense. Agents capable of mediating a response at the subcutaneous site would appear to warrant greatest attention.

Topics: Animals; Biological Factors; Colonic Neoplasms; Diosgenin; Disease Models, Animal; Diterpenes; Drug Screening Assays, Antitumor; Female; Heterocyclic Compounds, 3-Ring; HL-60 Cells; Humans; Inhibitory Concentration 50; KB Cells; Leukemia P388; Male; Melanoma; Mice; Molecular Structure; Naphthoquinones; Ovarian Neoplasms; Paclitaxel; Polymers; Prostatic Neoplasms; Triterpenes; Tumor Cells, Cultured

This study aims to evaluate the in vitro and in vivo leishmanicidal activity of lapachol, a naphthoquinone found in the seeds and heartwood of certain tropical plants, and to compare its efficacy with a reference drug, sodium stibogluconate (Pentostam(R)). These compounds (0.0125-4.0 mg/mL) were evaluated in vitro against intracellular amastigotes of Leishmania (Viannia) braziliensis (LVb), then tested in an animal model (hamster) to try to reproduce the leishmanicidal activity. In vitro, lapachol exhibited an anti-amastigote effect, whereas in vivo it did not prevent the development of LVb-induced lesions at an oral dose of 300 mg/kg/day for 42 days. Pentostam(R) demonstrated a significant anti-amastigote effect in vitro for LVb and apparent clinical cure in vivo (60 mg/kg/day). However, it could not completely eradicate parasites from the tissues of infected animals. The observation that lapachol exerts leishmanicidal activity in vitro without offering significant protection against LVb-infected lesions in hamsters suggests that lapachol in vivo might possibly inhibit the microbicidal functioning of macrophages. Alternatively, it might be transformed into an inactive metabolite(s) or neutralized, losing its leishmanicidal activity. It is also possible that an optimal and sustained plasma level of the drug could not be achieved at the dose used in this study.

Topics: Animals; Antimony Sodium Gluconate; Antiprotozoal Agents; Cricetinae; Disease Models, Animal; Female; Leishmania braziliensis; Leishmaniasis, Cutaneous; Macrophages, Peritoneal; Male; Mesocricetus; Mice; Naphthoquinones; Plants, Medicinal

Epidemiological evidence suggests a lower incidence of Parkinson's disease in smokers than in nonsmokers. This evidence, together with the lower levels of brain monoamine oxidase (MAO) activity in smokers and the potential neuroprotective properties of MAO inhibitors, prompted studies which led to the isolation and characterization of 2,3,6-trimethyl-1,4-naphthoquinone (TMN), an MAO-A and MAO-B inhibitor which is present in tobacco and tobacco smoke. Results of experiments reported here provide evidence that this compound protects against the MPTP-mediated depletion of neostriatal dopamine levels in the C57BL/6 mouse. These results support the hypothesis that the inhibition of MAO by constituents of tobacco smoke may be related to the decreased incidence of Parkinson's disease in smokers.

Topics: Animals; Brain; Disease Models, Animal; Dopamine; Mice; Mice, Inbred C57BL; Monoamine Oxidase; Monoamine Oxidase Inhibitors; Naphthoquinones; Neostriatum; Neuroprotective Agents; Nicotiana; Parkinsonian Disorders; Plant Extracts; Plants, Toxic

We examined the effects of a 35% ethanol extract (IB) from the petals of Impatiens balsamina L. and the principal active compounds from IB on chronic and serious pruritus and the development of dermatitis using NC mice, a model of atopic dermatitis. IB at 100 mg/kg significantly inhibited serious scratching behaviour in the NC mouse with established dermatitis when administered i.v. 1 h before, or p.o. 24 h before the measurement. A 10 microg/kg dose of kaempferol 3-rutinoside and 2-hydroxy-1,4-naphthoquinone (lawsone) isolated from IB also inhibited scratching behaviour in the NC mouse with established dermatitis. When 4-week-old NC mice with no symptoms were administered orally 100 mg/kg/day of IB until 13 weeks of age, protection was also noted against scratching behaviour during the development of dermatitis. IB was effective for the prevention and treatment of atopic dermatitis.

Topics: Animals; Antipruritics; Behavior, Animal; China; Dermatitis, Atopic; Disease Models, Animal; Drugs, Chinese Herbal; Glucosides; Impatiens; Male; Mice; Mice, Inbred Strains; Naphthoquinones; Phytotherapy; Plant Extracts; Plant Structures; Plants, Medicinal; Pruritus; Quercetin

Mice were infected intraperitoneally with 10,000 tachyzoites of Toxoplasma gondii (RH) strain and, 24 h later, were treated orally for 10 days with atovaquone and azithromycin, either alone or in combination. Evaluation of the efficacy of the drugs was performed by microscopic examination of smears prepared from the organs of the mice, and by subinoculation of visceral and brain suspensions from surviving mice into healthy mice at the end of the experiments. It was found that 58%, 83% and 100% of the mice survived after administration of 75, 150 or 200 mg/kg per day of azithromycin, respectively. Moreover, 8%, 17% and 25% of the mice survived after treatment with atovaquone at 20, 50 or 100 mg/kg per day, respectively. No synergistic or additive effects of combinations of atovaquone and azithromycin were observed. However, azithromycin did not eradicate the parasite from the brain and viscera of the infected mice, whereas atovaquone at 20, 50 and 100 mg/kg per day removed the parasite from viscera and at 100 mg/kg per day eradicated the parasite from the brain of infected mice. The combinations of atovaquone and azithromycin failed to completely eradicate the parasite from the brain and viscera of infected mice.

Topics: Animals; Anti-Bacterial Agents; Antiprotozoal Agents; Atovaquone; Azithromycin; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Female; Mice; Naphthoquinones; Random Allocation; Toxoplasma; Toxoplasmosis, Animal

The oxidation of naphthalene-1,2-dihydrodiol (ND) to o-naphthoquinone (NQ) in the lens is believed to be responsible for the formation of cataracts in naphthalene-fed rats. Studies using either recombinant rat lens (RLAR) or human muscle aldose reductase (HMAR) incubated in vitro with ND in the presence of NAD(P) verified that aldose reductase (EC 1.1.1.21) is the dihydrodiol dehydrogenase that catalyzes the oxidation of ND to NQ. Kinetic studies of Vmax/Km indicated that RLAR catalyzes the NAD-dependent oxidation of ND with an optimal pH of 9.0. The corresponding activity of HMAR was lower than that of rat enzyme. The metabolite produced by the incubation of RLAR with ND in the presence of 2-mercaptoethanol and NAD in 20 mM phosphate buffer, pH 7.5, was isolated by C18 reversed-phase high-performance liquid chromatography. The elution profile showed the formation of a new peak that was identical with a peak generated when NQ was incubated under the same condition. The metabolite in both peaks was identified as 4-(2-hydroxyethylsulfanyl)-1, 2-dihydro-1,2-naphthalenedione (HNQ) by 1H and 13C NMR analyses using homonuclear correlation spectroscopy, heteronuclear multiple quantum coherence, and heteronuclear shift correlations via multiple bond connectivities as well as infrared analysis. HNQ is readily autoxidized to 2,3-dihydro-1-oxa-4-thia-9,10-phenanthrenedione. The stoichiometry of 1:1 between the consumption of ND and the formation of NADH for the formation of HNQ implies that rat lens aldose reductase catalyzes a 2e- oxidation of ND to yield the corresponding ketol, which is autoxidized to NQ.

Topics: Aldehyde Reductase; Animals; Cataract; Cells, Cultured; Disease Models, Animal; Humans; Lens, Crystalline; Naphthols; Naphthoquinones; Oxidation-Reduction; Rats

Using an ethnomedical-based drug discovery program, two previously unknown compounds (SP-18904 and SP-18905) from Pycnanthus angolensis were isolated that lower glucose concentrations in mouse models of type 2 diabetes. SP-18904 and SP-18905 are terpenoid-type quinones that significantly lowered plasma glucose concentration (p <.05) when given orally to either ob/ob or db/db mice, both of which are hyperglycemic and hyperinsulinemic. The antihyperglycemic actions of SP-18904 and SP-18905 were associated with significant decreases in plasma insulin concentrations (p <.05), suggesting that both compounds lowered glucose by enhancing insulin-mediated glucose uptake. This was supported by the insulin suppression test in ob/ob mice. Studies in hyperglycemic, insulin-deficient mice and in vitro experiments on 3T3-L1 adipocytes further supported this conclusion. As such, these two terpenoid-type quinones represent a new class of compounds of potential use in the treatment of type 2 diabetes.

Topics: Adipocytes; Animals; Blood Glucose; Cells, Cultured; Diabetes Mellitus, Experimental; Diabetes Mellitus, Type 2; Disease Models, Animal; Eating; Hypoglycemic Agents; Insulin; Male; Mice; Mice, Inbred C57BL; Naphthoquinones; Plant Extracts; Plants, Medicinal; Trees

Topics: Animals; Carbamates; Cryptosporidiosis; Cryptosporidium parvum; Dexamethasone; Disease Models, Animal; Female; Ileum; Immunocompromised Host; Lung; Naphthoquinones; Pneumocystis; Pneumonia, Pneumocystis; Prodrugs; Rats; Rats, Sprague-Dawley

Terbinafine is a synthetic antifungal agent which has recently been found to be highly effective against Pneumocystis carinii. This study evaluated the efficacy of terbinafine on rat P. carinii antigenic profile and the immune response by Western blot analysis, in comparison with atovaquone and co-trimoxazole in rats with pneumocystosis. Terbinafine was shown to target two specific major antigens, particularly those of 116 and 35-40 kDa. Antibodies reactive against these moieties were found in all rats treated with atovaquone and co-trimoxazole, but not in those treated with terbinafine. These surface antigen modifications could be related to disease severity and could provide additional information for monitoring the efficacy of this treatment.

Topics: Animals; Antifungal Agents; Antigens, Fungal; Atovaquone; Blood; Blotting, Western; Bronchoalveolar Lavage Fluid; Disease Models, Animal; Electrophoresis; Immunosuppression Therapy; Male; Naphthalenes; Naphthoquinones; Pneumocystis; Pneumonia, Pneumocystis; Rats; Rats, Sprague-Dawley; Survival Rate; Terbinafine; Trimethoprim, Sulfamethoxazole Drug Combination

To evaluate the effects of drug therapy on the clinical course of acute acquired Toxoplasma retinochoroiditis and on the number of Toxoplasma cysts present in the brain and ocular tissues in the hamster animal model.. The Syrian golden hamster animal model of Toxoplasma retinochoroiditis was used. In acute disease, systemically administered atovaquone was compared with conventional therapies (pyrimethamine combined with sulfadiazine; clindamycin; and spiramycin). The clinical course of the ocular disease was determined with retinal examination and photography of the fundus. The number of Toxoplasma cysts remaining after treatment was evaluated in aliquots of brain homogenate and in retinal tissue. The effect of atovaquone on cerebral Toxoplasma cyst count was also studied in chronic disease.. None of the drugs administered altered the course of the acute disease, judged by clinical examination. Atovaquone alone significantly reduced the number of cerebral Toxoplasma cysts after acute disease. Atovaquone also significantly reduced the cerebral Toxoplasma cyst count in chronic disease.. Tissue cysts are believed to be responsible for reactivation of Toxoplasma retinochoroiditis. Atovaquone has the potential to reduce the risk of recurrent disease.

Topics: Acute Disease; Animals; Anti-Bacterial Agents; Antiprotozoal Agents; Atovaquone; Brain; Chorioretinitis; Chronic Disease; Cricetinae; Disease Models, Animal; Drug Therapy, Combination; Female; Mesocricetus; Naphthoquinones; Retina; Toxoplasma; Toxoplasmosis, Cerebral; Toxoplasmosis, Ocular

The aim of this work was to develop a new pharmaceutical form of atovaquone and to study its activity against Toxoplasma gondii in vitro and in vivo. Nanocapsules were chosen as the oral dosage form of administration. An analytical method was developed to determine the drug content in nanocapsules. The stability of these nanocapsules were assessed by following drug content, size, pH and osmolarity for a period of six months. The in vitro activity of atovaquone-loaded nanocapsules against tachyzoites of T. gondii (RH stain) was comparable to its suspension form. In vivo studies were carried out in murine models of acute and chronic toxoplasmosis. Mice acutely infected with the virulent RH strain were orally treated with a dose regimen of 15 mg/kg/day for 10 days, starting from day 1 post-infection. 75% of the mice receiving atovaquone-loaded nanocapsules survived 30 days post-infection, compared to none of untreated controls and none of mice treated with the suspension with the same dose regimen. In mice chronically infected by the COUL or the ME49 strain (Type II strains), then treated for six weeks, treatment with atovaquone (15 mg/kg/d, nanoparticles or suspension) resulted in a decrease of brain parasitic burden, which was significantly more pronounced in ME49-infected mice and in those treated with drug-loaded nanocapsules. These results show that the sensibility of T. gondii to atovaquone is different according to the strains and that the activity of atovaquone in the treatment of toxoplasmosis is enhanced when administered in nanoparticular form.

Topics: Acute Disease; Administration, Oral; Animals; Antiprotozoal Agents; Atovaquone; Brain; Capsules; Chronic Disease; Colloids; Disease Models, Animal; Drug Carriers; Drug Stability; Female; Lung; Mice; Naphthoquinones; Parasitemia; Solubility; Survival Rate; Suspensions; Temperature; Toxoplasma; Toxoplasmosis, Animal

This study demonstrates the activity of the hydroxynaphthoquinone (HNQ), atovaquone, against Babesia divergens, the cause of a rare but lethal form of human babesiosis. In vitro studies showed that unlike other anti-malarial drugs, the HNQs studied have a high level of anti-babesial activity and atovaquone was more active than imidocarb, the most effective compound used so far for human B. divergens babesiosis and also used routinely for the treatment of bovine babesiosis. Atovaquone also proved to be extremely active against B. divergens in gerbils (Meriones unguiculatus). Acute fulminating infections were effectively treated with as little as 1.0 mg/kg with increasing effectiveness up to 10 mg/kg, which compares well with the activity of imidocarb. Although immunosuppression with dexamethasone slowed the decline of parasitemias after treatment with atovaquone, gerbil survival was unaffected. Pretreatment of gerbils with 4 daily low doses of atovaquone did not have any effect on the development of subsequent infections. However, if treatment was continued after infection, daily doses as low as 0.5 mg/kg effectively suppressed the parasites.

Topics: Acute Disease; Animals; Antiprotozoal Agents; Atovaquone; Babesia; Babesiosis; Cattle; Cells, Cultured; Disease Models, Animal; Dose-Response Relationship, Drug; Erythrocytes; Gerbillinae; Hemoglobinuria; Humans; Naphthoquinones; Parasitemia; Regression Analysis

Sixteen Saimiri sciureus monkeys were administered PS-15-atovaquone, PS-15-sulfamethoxazole, PS-15-dapsone, PS-15 alone, and atovaquone alone. The in vitro antimalarial activity of serum against Plasmodium falciparum obtained from these monkeys at 3, 6, and 12 hr after the administration of drug(s) were measured by bioassay and analyzed by Duncan's and Newman-Keul's tests. PS-15-atovaquone was found to be the most effective antimalarial combination, followed by PS-15-sulfamethoxazole, PS-15-dapsone, PS-15 alone, and atovaquone alone. These dual PS-15 combinations are effective combinations and, in-particular, PS-15-atovaquone is worthy of further evaluation.

Topics: Animals; Antimalarials; Atovaquone; Biological Assay; Dapsone; Disease Models, Animal; Drug Synergism; Drug Therapy, Combination; Humans; Malaria, Falciparum; Naphthoquinones; Proguanil; Regression Analysis; Saimiri; Sulfamethoxazole

The traditional therapy for the treatment of human Babesia microti infections has been the combination of clindamycin and quinine. However, in recent years, it has become apparent that some patients have not responded to this regimen. We became involved in the treatment of several cases of babesiosis in which atovaquone was used to treat this infection. Therefore, using the hamster model, we determined the efficacy of atovaquone alone as well as atovaquone plus azithromycin for the treatment of experimental babesiosis. Atovaquone (100 mg/kg/day) and atovaquone (100 mg/kg/day) with azithromycin (150 mg/kg/day) were effective agents for the treatment of experimental babesiosis in hamsters. When atovaquone was used as monotherapy recrudescences occurred. Organisms obtained from recrudescent animals, when inoculated into uninfected animals, proved to be unresponsive to atovaquone therapy, suggesting the emergence of drug resistance. Resistant organisms did not emerge in hamsters treated with the combination of atovaquone and azithromycin. Atovaquone should be considered in the therapeutic regimen of patients with babesiosis who have either failed standard therapy or have become intolerant to such therapy.

Topics: Animals; Anti-Bacterial Agents; Antimalarials; Antiprotozoal Agents; Artemisinins; Atovaquone; Azithromycin; Babesiosis; Cricetinae; Disease Models, Animal; Drug Therapy, Combination; Naphthoquinones; Parasitemia; Recurrence; Sesquiterpenes

The effectiveness of combinations of rifabutin with atovaquone, clindamycin, pyrimethamine, or sulfadiazine in the treatment of toxoplasmic encephalitis in a murine model was investigated. Doses of each drug that were not effective in reducing inflammation in the brain of mice with toxoplasmic encephalitis when used alone were used in combination with a dose of rifabutin which was minimally effective. At the end of each period of therapy (15 or 30 days), brains of mice were examined histopathologically and the severity of the inflammatory lesions scored. Treatment with rifabutin in combination with pyrimethamine or sulfadiazine did not reduce brain inflammation significantly when compared to treatment with each drug alone. In contrast, treatment with rifabutin plus atovaquone for 15 or 30 days or with rifabutin plus clindamycin for 15 days resulted in statistically significant reduction in the inflammation. These results suggest that combining rifabutin with certain drugs that are active against Toxoplasma gondii may be useful for the treatment of toxoplasmic encephalitis in humans and may allow for a reduction in dosage of either or both drugs with a resulting reduction in untoward side effects.

Topics: Animals; Anti-Bacterial Agents; Anti-Infective Agents; Antiprotozoal Agents; Atovaquone; Brain; Clindamycin; Disease Models, Animal; Drug Therapy, Combination; Encephalitis; Female; Mice; Mice, Inbred CBA; Naphthoquinones; Pyrimethamine; Rifabutin; Sulfadiazine; Toxoplasmosis, Cerebral; Treatment Outcome

Several drugs have been shown to have anti-Pneumocystis carinii activity in clinical trials. Because of the large number of patients required, no more than 3 drugs can be compared for efficacy in human studies. However, the experimental animal model for P. carinii pneumonitis is remarkably similar to the human disease and was used to compare 10 drugs for the relative potency against this infection. All drugs were compared at doses known to prevent the pneumonitis in > 80% of animals and at one-tenth of this dose. Drugs effective at the lowest dose were further tested at one-hundredth the original doses, and drugs ineffective were retested at 10 and 100 times the original dose. Trimethoprim-sulfamethoxazole was the most effective drug, with azithromycin-sulfamethoxazole and clarithromycin-sulfamethoxazole next most effective. Intravenous pentamidine and clindamycin-primaquine were the least effective. Atovaquone, sulfadoxine-pyrimethamine, erythromycin-sulfisoxazole, PS-15, and dapsone-trimethoprim had intermediate activity.

Topics: Animals; Anti-Infective Agents; Atovaquone; Azithromycin; Clarithromycin; Clindamycin; Clinical Trials as Topic; Dapsone; Disease Models, Animal; Drug Evaluation, Preclinical; Drug Therapy, Combination; Humans; Naphthoquinones; Pentamidine; Pneumocystis Infections; Proguanil; Pyrimethamine; Rats; Sulfadoxine; Sulfamethoxazole; Trimethoprim; Trimethoprim, Sulfamethoxazole Drug Combination

Plumbagin, 3,3'-biplumbagin and 8,8'-biplumbagin are naphthoquinones isolated by activity-directed fractionation from a Bolivian plant, Pera benensis, used in folk medicine as treatment of cutaneous leishmaniasis caused by Leishmania braziliensis. BALB/c mice were infected with L. mexicana or L. venezuelensis and treated 24 h after the parasitic infection with plumbagin (5 or 2.5 mg/kg/day), 3,3'-biplumbagin, 8,8'-biplumbagin (25 mg/kg/d) or Glucantime (200 mg/kg/d). Lesion development was the criteria employed to evaluate the inhibitory effect. The bis-naphthoquinones were less potent than Glucantime against L. amazonensis and L. venezuelensis. Plubagin and Glucantime delayed the development of L. amazonensis and L. venezuelensis. Assays of a single local treatment on foot-pad infection two weeks after the parasitic inoculation with L. amazonensis showed that 8,8'-biplumbagin (50 mg/kg/d) was as potent as Glucantime (400 mg/kg/d).

Topics: Animals; Antiprotozoal Agents; Disease Models, Animal; Female; Leishmaniasis, Cutaneous; Leishmaniasis, Mucocutaneous; Male; Meglumine; Meglumine Antimoniate; Mice; Mice, Inbred BALB C; Naphthoquinones; Organometallic Compounds; Plant Extracts

1. The radical cure of human malaria caused by Plasmodium vivax requires two drugs, i.e., a blood schizontocide such as chloroquine to clear the circulating parasites, and primaquine aimed at the liver stages (hyponozoites) responsible for the late relapses of this parasite. Primaquine is unique as a radical curative drug but is highly toxic. The only useful model currently available for screening drugs to replace primaquine is Plasmodium cynomolgi-induced malaria in Rhesus monkeys. Because of the limited availability and cost of these animals, the development of non-primate models for such screening would be of considerable value. 2. We used a drug-screening assay for the liver stage malaria parasite based on the ability of such drugs to stop development of gametocytes in the mosquito vector. The inhibition of the sporogonic cycle of malaria in the mosquito by primaquine (15 mg/kg) was confirmed here and used for re-evaluation of the gametocyte method. 3. We observed that the level of parasitemia in the untreated control chicken used to infect mosquitos was a crucial factor affecting the subsequent development of sporogony. Thus, parasitemia was carefully controlled in the studies involving oocyst development. Parasitemias lower than 6% at the beginning of the experiment and increasing were found to be most appropriate for the production of the infectious gametocytes during a period of 8 h.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Aedes; Animals; Brazil; Chickens; Disease Models, Animal; Drug Evaluation, Preclinical; Liver; Malaria, Vivax; Naphthoquinones; Plant Extracts; Plants, Medicinal; Plasmodium gallinaceum

Toxoplasmosis is a frequent opportunistic infection in patients with AIDS. In these patients the major immune deficiencies are a severe depletion of CD4+ T lymphocytes and an impaired capacity to produce IFN-gamma. A mouse model was developed and used to study the effects that depletion of CD4+ T cells and/or inhibition of the protective activity of IFN-gamma have on the effectiveness of the drug therapy for toxoplasmosis. Infection of mice with a lethal inoculum of Toxoplasma gondii cysts followed by treatment with the hydroxynaphthoquinone 566C80 or with sulfadiazine resulted in 100% survival whereas untreated controls had 100% mortality within 15 days of infection. Administration of antiserum to IFN-gamma resulted in early death of untreated mice and in 30% mortality in those treated. Administration of mAb to CD4+ T cells followed by infection with T. gondii prevented the development of both antibody and cell-mediated immune responses against the parasite. These mice resisted the acute infection while undergoing specific treatment. Discontinuation of the treatment, however, resulted in reactivation of the infection and the majority of the animals died within 17 days of suspension of the treatment. Administration of antiserum to IFN-gamma or to CD4+ T cells 24 h but not 15 days after conclusion of the treatment also resulted in mortality. These results indicate that successful treatment of toxoplasmosis depends on the status of the immune system, particularly of CD4+ T cells. Although it is speculative to compare results obtained in mice to the situation in humans, our work suggests that restoration of a competent immune response is of crucial importance for a successful treatment of toxoplasmosis in immunocompromised individuals.

Topics: Animals; Antibodies, Protozoan; Antiprotozoal Agents; Atovaquone; CD4-Positive T-Lymphocytes; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Female; Hypersensitivity, Delayed; Immunity, Cellular; Interferon-gamma; Lymphocyte Depletion; Mice; Naphthoquinones; Toxoplasmosis, Animal; Treatment Failure

Topics: Animals; Cattle; Disease Models, Animal; Female; Naphthoquinones; Theileriasis

Topics: Acetone; Animals; Coumarins; Disease Models, Animal; Naphthoquinones; Photosensitivity Disorders; Radiation Effects; Rats; Skin; Sunscreening Agents; Time Factors; Trioses; Ultraviolet Rays