gambogic-acid and Disease-Models--Animal

Mastitis is one of the most common diseases among dairy cows. There is still much debate worldwide as to whether antibiotic therapy should be given to dairy cows, or if natural products should be taken as a substitute for antibacterial therapy. As the antibiotic treatment leads to the bacterial resistance and drug residue in milk, introducing natural products for mastitis is becoming a trend. This study investigates the mechanisms of the protective effects of the natural product gambogic acid (GA) in lipopolysaccharide (LPS)-induced mastitis. For in vitro treatments, it was found that GA reduced IL-6, TNF-α, and IL-1β levels by inhibiting the phosphorylation of proteins in the nuclear factor κB (NF-κB) and the mitogen-activated protein kinase (MAPK) pathway. GA also maintained a stable membrane mitochondrial potential and inhibited the overproduction of reactive oxygen species, which protected the cells from apoptosis. On the other hand, in vivo treatments with GA were found to reduce pathological symptoms markedly, and protected the blood-milk barrier from damage induced by LPS. The results demonstrate that GA plays a vital role in suppressing inflammation, alleviating the apoptosis effect, and protecting the blood-milk barrier in mastitis induced by LPS. Thus, these results suggest that the natural product GA plays a potential role in mastitis treatment.

Topics: Animals; Anti-Inflammatory Agents; Apoptosis; Caspase 3; Caspase 9; Cell Line; Cytokines; Disease Models, Animal; Epithelial Cells; Female; Inflammation; Lipopolysaccharides; Mammary Glands, Animal; MAP Kinase Signaling System; Mastitis; Membrane Potential, Mitochondrial; Mice; NF-kappa B p50 Subunit; Phosphorylation; Pregnancy; Proto-Oncogene Proteins c-bcl-2; Reactive Oxygen Species; Xanthones

Neurotrophic factors and their corresponding receptors play key roles in the maintenance of different phenotypic dorsal root ganglion (DRG) neurons, the axons of which degenerate in small fiber neuropathy, leading to various neuropathic manifestations. Mechanisms underlying positive and negative symptoms of small fiber neuropathy have not been systematically explored. This study investigated the molecular basis of these seemingly paradoxical neuropathic behaviors according to the profiles of TrkA and Ret with immunohistochemical and pharmacological interventions in a mouse model of resiniferatoxin (RTX)-induced small fiber neuropathy. Mice with RTX neuropathy exhibited thermal hypoalgesia and mechanical allodynia, reduced skin innervation, and altered DRG expression profiles with decreased TrkA(+) neurons and increased Ret(+) neurons. RTX neuropathy induced the expression of activating transcription factor 3 (ATF3), and ATF3(+) neurons were colocalized with Ret but not with TrkA (P<0.001). As a neuroprotectant, 4-Methylcatechol (4MC) promoted skin reinnervation partially with correlated reversal of the neuropathic behaviors and altered neurochemical expression. Gambogic amide, a selective TrkA agonist, normalized thermal hypoalgesia, and GW441756, a TrkA kinase inhibitor, induced thermal hypoalgesia, which was already reversed by 4MC. Mechanical allodynia was reversed by a Ret kinase inhibitor, AST487, which induced thermal hyperalgesia in naïve mice. The activation of Ret signaling by XIB4035 induced mechanical allodynia and thermal hypoalgesia in RTX neuropathy mice in which the neuropathic behaviors were previously normalized by 4MC. Distinct neurotrophic factor receptors, TrkA and Ret, accounted for negative and positive neuropathic behaviors in RTX-induced small fiber neuropathy, respectively: TrkA for thermal hypoalgesia and Ret for mechanical allodynia and thermal hypoalgesia.

Topics: Animals; Disease Models, Animal; Diterpenes; Mice; Pain Measurement; Proto-Oncogene Proteins c-ret; Quinolines; Receptor, trkA; Small Fiber Neuropathy; Xanthones

The epithelial-to-mesenchymal transition (EMT) contributes to the disruption of cell-cell junctions and imbues cancer cells with invasive and migratory properties. In this study, we investigated the effect of gambogic acid, a xanthone extracted from the resin of Garciania hanburyi, on transforming growth factor β1 (TGFβ1)-induced EMT. Gambogic acid inhibited the invasion and migration of TGFβ1-induced A549 cells in vitro. Gambogic acid also increased the mRNA and protein expression of E-cadherin, but repressed the mRNA and protein expression of N-cadherin, vimentin, and transcription factor TWIST1. Further examination of the mechanism revealed that the nuclear factor κB (NF-κB) pathway is involved in this regulation of EMT-related biomarkers. Gambogic acid inhibited NF-κB p65 nuclear translocation and the phosphorylation of the inhibitor of NF-κB (IκBα) and IκBα kinase (IKKα). Gambogic acid also suppressed the EMT induced by TGFβ1 and tumor necrosis factor α by inhibiting the NF-κB pathway. Our data also indicate that gambogic acid inhibited the primary lesion and lung metastasis of orthotopic model of A549 cells in vivo. We propose that gambogic acid might be developed as a candidate drug with therapeutic potential for the treatment of cancer invasion and migration.

Topics: Animals; Antineoplastic Agents, Phytogenic; Cell Line, Tumor; Cell Movement; Cell Survival; Disease Models, Animal; Epithelial-Mesenchymal Transition; Gene Expression; Humans; Male; MAP Kinase Signaling System; Mice; NF-kappa B; RNA, Messenger; Signal Transduction; Smad Proteins; Snail Family Transcription Factors; Transforming Growth Factor beta1; Tumor Necrosis Factor-alpha; Xanthones; Xenograft Model Antitumor Assays

Gamboge is the dried resin secreted by the Garcinia maingayi gambogic tree and is a substance that may be used to treat a variety of diseases, exhibits anti‑tumor and detoxification effects and prevents bleeding. The primary active constituent is gambogic acid. The present study aimed to investigate the anti‑inflammatory effects of gambogic acid in rheumatoid arthritis (RA) rats and to elucidate the mechanisms by which these effects occur. The swelling degree, the clinical arthritic scoring and pain threshold measurements were used to evaluate the effects of gambogic acid on RA. ELISA kits and western blot analysis were used to investigate inflammatory processes and the expression of RA‑associated proteins, respectively. The present results demonstrated that gambogic acid significantly inhibited the degree of right foot swelling, increased pain thresholds and reduced clinical arthritic scores of RA rats. Treatment with gambogic acid suppressed the activities of interleukin (IL)‑1β and IL‑6, promoted the protein expression of phosphorylated (p)‑Akt serine/threonine kinase (Akt), p‑mammalian target protein of rapamycin (mTOR) and inhibited hypoxia‑inducible factor‑1α and vascular endothelial growth factor expression in RA rats. The results of the present study therefore suggest that the anti‑inflammatory effects of gambogic acid in RA rats occur via regulation of the phosphoinositide 3‑kinase/Akt/mTOR signaling pathway.

Topics: Animals; Arthritis, Rheumatoid; Disease Models, Animal; Hypoxia-Inducible Factor 1, alpha Subunit; Inflammation; Interleukin-1beta; Interleukin-6; Male; Pain Threshold; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Rats; Rats, Sprague-Dawley; Signal Transduction; TOR Serine-Threonine Kinases; Vascular Endothelial Growth Factor A; Xanthones

Resistance to chemotherapy is a great challenge to improving the survival of patients with diffuse large B-cell lymphoma (DLBCL), especially those with activated B-cell-like DLBCL (ABC-DLBCL). Therefore it is urgent to search for novel agents for the treatment of DLBCL. Gambogic acid (GA), a small molecule derived from Chinese herb gamboges, has been approved for Phase II clinical trial for cancer therapy by Chinese FDA. In the present study, we investigated the effect of GA on cell survival and apoptosis in DLBCL cells including both GCB- and ABC-DLBCL cells. We found that GA induced growth inhibition and apoptosis of both GCB- and ABC-DLBCL cells in vitro and in vivo, which is associated with proteasome malfunction. These findings provide significant pre-clinical evidence for potential usage of GA in DLBCL therapy particularly in ABC-DLBCL treatment.

Topics: Animals; Apoptosis; Caspases; Cell Line, Tumor; Cell Proliferation; Cell Survival; Disease Models, Animal; Enzyme Activation; Gene Expression Regulation, Neoplastic; Humans; Lymphoma, Large B-Cell, Diffuse; Male; Mice; Mice, Nude; NF-kappa B; Proteasome Endopeptidase Complex; Proteasome Inhibitors; Signal Transduction; Xanthones; Xenograft Model Antitumor Assays

We have previously reported a continuous activation of caspase-1 and increased interleukin (IL)-1β levels in early rheumatoid arthritis (RA). These observations raised the hypothesis that drugs targeting the IL-1β pathway, in addition to tumour necrosis factor (TNF), may be particularly effective for early RA treatment. We have recently identified gambogic acid as a promising therapeutic candidate to simultaneously block IL-1β and TNF secretion. Our main goal here was to investigate whether gambogic acid administration was able to attenuate inflammation in antigen-induced arthritis (AIA) rats.. Gambogic acid was administered to AIA rats in the early and late phases of arthritis. The inflammatory score, ankle perimeter, and body weight were evaluated during the period of treatment. Rats were sacrificed after 19 days of disease progression and paw samples were collected for histological and immunohistochemical evaluation.. We found that inflammation in joints was significantly suppressed following gambogic acid administration. Histological and immunohistochemical evaluation of treated rats revealed normal joint structures with complete abrogation of the inflammatory infiltrate and cellular proliferation.. Our results suggest that gambogic acid has significant anti-inflammatory properties and can possibly constitute a prototype anti-inflammatory drug with therapeutic efficacy in the treatment of inflammatory diseases such as RA.

Topics: Animals; Anti-Inflammatory Agents; Antigens; Arthritis, Experimental; Caspase 1; Cell Proliferation; Disease Models, Animal; Disease Progression; Female; Inflammation; Interleukin-1beta; Rats; Rats, Wistar; Tumor Necrosis Factor-alpha; Xanthones

Psoriasis is a chronic T cell-mediated inflammatory skin disease. Studies have shown that angiogenesis plays an important role in the pathogenesis of psoriasis. Studies have also indicated that Gambogic acid (GA) inhibits angiogenesis and may be a viable drug candidate in anti-angiogenesis therapies.. The aim of this study was to investigate the anti-psoriatic effect of GA and the possible mechanisms.. MTT test on HaCaT cells and immunofluorescence on HUVEC cells were processed. An O/W cream of GA was prepared and topically applied to the ears of K14-VEGF transgenic mice and psoriasis-like guinea-pigs, and the tail skin of Balb/C mice independently. Furthermore, hematoxylin-eosin staining of tissues from three models and immunohistochemistry staining of ear samples from K14-VEGF mice were performed.. In vitro, GA inhibited proliferation of HaCaTs and TNF-α-induced activation of NF-κB in HUVECs. In vivo, animals treated with GA showed significant morphological and histological improvements. Immunohistochemical analysis of K14-VEGF transgenic mice revealed that hyperplastic and inflamed vessels were suppressed with GA treatment. The expression of adhesion molecules such as ICAM-1 and E-selectin was significantly decreased. GA inhibited angiogenesis and the expression of VEGFR2 and p-VEGFR2. T lymphocyte infiltration and the expression of IL-17 and IL-22 were also reduced by GA treatment.. Our results suggest that GA has anti-psoriatic efficacy through inhibition of angiogenesis and inflammation. Therefore, GA is attractive and offers future potential for application in patients with psoriasis.

Topics: Animals; Cell Line; Disease Models, Animal; Drug Evaluation, Preclinical; Garcinia; Guinea Pigs; Human Umbilical Vein Endothelial Cells; Humans; Hyperplasia; Inflammation; Mice, Transgenic; Neovascularization, Pathologic; NF-kappa B; Phytotherapy; Plant Extracts; Plants, Medicinal; Psoriasis; Random Allocation; Skin; T-Lymphocytes; Tumor Necrosis Factor-alpha; Vascular Endothelial Growth Factor A; Xanthones

In multiple myeloma (MM), the hypoxic environment is an important factor causing tumor angiogenesis, which is strongly correlated to disease progression and unfavorable outcome by activating the key transcription factor, hypoxia-inducible factor-1α (HIF-1α). Gambogic acid (GA) is the major active ingredient of gamboge, which has been shown to possess antitumor effect by in vitro and in vivo study. However, the underlying molecular mechanism of whether GA inhibits tumor angiogenesis remains poorly understood. In this study, we investigated the effects of GA on expression of HIF-1α, and its downstream target gene vascular endothelial growth factor (VEGF) in human MM U266 cells. We found that hypoxia induced increase in the level of HIF-1α subunit protein and activated the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target protein of rapamycin (mTOR) pathway. Moreover, the treatment with GA markedly decreased HIF-1α and VEGF expression under hypoxic conditions. Mechanistic studies exhibited that GA inhibited the production of HIF-1α by reducing phosphorylation of Akt and mTOR in U266 cells. Furthermore, in vivo study revealed that intravenous injection of GA once every other day for 2 weeks could suppress tumor volumes by antiangiogenesis activity. Taken together, our results identify that GA suppresses hypoxia-activated pathways that are linked to MM progression, at least partly, by the inhibition of the PI3K/Akt/mTOR signaling pathway. Therefore, GA may be a new potent therapeutic agent against human MM cells.

Topics: Animals; Antineoplastic Agents; Blotting, Western; Cell Hypoxia; Cell Line, Tumor; Disease Models, Animal; Enzyme-Linked Immunosorbent Assay; Fluorescent Antibody Technique; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Male; Mice; Mice, Inbred BALB C; Multiple Myeloma; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; Real-Time Polymerase Chain Reaction; Signal Transduction; Vascular Endothelial Growth Factor A; Xanthones; Xenograft Model Antitumor Assays

Ovarian cancer is one human malignancy which has response portly to doxorubicin. The anti-cancer activity of gambogic acid has been tested in in vitro and in vivo studies. In this study, we showed that gambogic acid, a natural compound, could potentiate the anticancer activity of doxorubicin in ovarian cancer through ROS-mediated apoptosis. Platinum-resistant human ovarian cancer cell line (SKOV-3) was treated with gambogic acid, doxorubicin, or the combination of both to investigate cell proliferation and apoptosis. We found that the combination of gambogic acid and doxorubicin causes synergistic loss of cell viability in SKOV-3 cells and this synergistic effect correlated with increased cellular ROS accumulation. Moreover, in vivo results showed that gambogic acid and doxorubicin combination resulted in a synergistic suppressing effect on tumor growth in ovarian cancer mice model. Taken together, the results suggested that doxorubicin in combination with gambogic acid might provide a promising therapeutic strategy to enhance chemosensitivity of ovarian cancer to doxorubicin.

Topics: Animals; Antineoplastic Agents; Apoptosis; Caspase 3; Cell Line, Tumor; Disease Models, Animal; Doxorubicin; Drug Resistance, Neoplasm; Drug Synergism; Female; Humans; JNK Mitogen-Activated Protein Kinases; Mice; Ovarian Neoplasms; p38 Mitogen-Activated Protein Kinases; Reactive Oxygen Species; Transplantation, Heterologous; Xanthones