curcumin and artemisinin

The formation of blood capillaries to sustain development and growth of new tissues is referred to as angiogenesis. Angiogenesis is pivotal in both carcinogenesis and metastasis since capillaries are the sole source of supplying nutrients and oxygen to the proliferating tumor cells; therefore, this dependency of tumor growth on angiogenesis challenges researchers to halt tumor growth by targeting angiogenesis with the help of either synthetic or natural inhibitors. Many synthetic inhibitors of angiogenesis have not only come into force but also resulted in some severe adverse effects. Natural compounds may effectively fit into this condition and possibly decrease the time of treatment. In the recent past, literature is replete with evidences advocating the usefulness of natural compounds that target multiple biochemical pathways. The additional advantage of natural compounds is that their active principles interact with one another and work synergistically to give more meaningful and reliable effects than individual principle. Hence, if we are somehow able to combine more than two natural compounds, then it may be possible to enhance their potential by many folds, which shall prove to be very effective in combating tumor angiogenesis. This review shall discuss the concept of angiogenesis, molecular pathways, and angiogenic inhibitors and their specific targets and potential of natural compounds to greatly enhance the current knowledge of angiogenesis-inhibiting factors.

Topics: Angiogenesis Inducing Agents; Angiogenesis Inhibitors; Artemisinins; Catechin; Cell Proliferation; Curcumin; Humans; Neoplasms; Neovascularization, Pathologic; Plant Extracts; Resveratrol; Stilbenes; Triterpenes

During the past several years, our laboratory has been investigating the anticoccidial activities of various natural products that have potential use as dietary supplements for coccidiosis control. Sources of fats containing high concentrations of n-3 fatty acids such as menhaden oil and flaxseed oil and flaxseed, when added to starter rations and fed to chicks from one day of age, effectively reduce lesions caused by the caecal parasite Eimeria tenella, but not lesions caused by Eimeria maxima. Our results are consistent with reports of effects of diets high in n-3 fatty acids on other protozoan parasites which suggest that the state of oxidative stress induced by these diets in the cells of both host and parasites is responsible for their parasitic actions. Artemisinin, a naturally occurring (Artemisia annua) endoperoxide and effective antimalarial significantly lowers lesions from E. tenella when given at low levels as a feed additive. The mechanism of its action is also considered to involve induction of oxidative stress. Diets supplemented with 8 p.p.m. gamma-tocopherol (abundant in flaxseeds) or with 1% of the spice tumeric, reduce mid-small intestinal lesion scores and improve weight gains during E. maxima infections. These compounds may exert their anticoccidial activity because they are effective antioxidants. Betaine, a choline analogue found in high concentrations in sugar beets, improves nutrient utilisation by animals under stress. When provided as a dietary supplement at a level of 0.15% it has enhanced the anticoccidial activity of the ionophore, salinomycin. Betaine may act as an osmoprotectant whereby it improves the integrity and function of the infected intestinal mucosa. In in vivo studies, betaine plus salinomycin significantly inhibit invasion of both E. tenella and E. acervulina. However, subsequent development of E. acervulina is inhibited more effectively with this combination treatment than development of E. tenella.

Topics: Animals; Antiprotozoal Agents; Artemisinins; Betaine; Chickens; Coccidiosis; Curcumin; Eimeria; Enzyme Inhibitors; Fatty Acids, Omega-3; Gastrointestinal Agents; Poultry Diseases; Sesquiterpenes; Vitamin E

Natural products have emerged as "rising stars" for treating viral diseases and useful chemical scaffolds for developing effective therapeutic agents. The nonstructural protein NS5B (RNA-dependent RNA polymerase) of NADL strain BVDV was used as the action target based on a molecular docking technique to screen herbal monomers for anti-BVDV viral activity. The in vivo and in vitro anti-BVDV virus activity studies screened the Chinese herbal monomers with significant anti-BVDV virus effects, and their antiviral mechanisms were initially explored. The molecular docking screening showed that daidzein, curcumin, artemisinine, and apigenin could interact with BVDV-NADL-NS5B with the best binding energy fraction. In vitro and in vivo tests demonstrated that none of the four herbal monomers significantly affected MDBK cell activity. Daidzein and apigenin affected BVDV virus replication mainly in the attachment and internalization phases, artemisinine mainly in the replication phase, and curcumin was active in the attachment, internalization, replication, and release phases. In vivo tests demonstrated that daidzein was the most effective in preventing and protecting BALB/C mice from BVDV infection, and artemisinine was the most effective in treating BVDV infection. This study lays the foundation for developing targeted Chinese pharmaceutical formulations against the BVDV virus.

Topics: Animals; Apigenin; Cell Line; Curcumin; Diarrhea Viruses, Bovine Viral; Medicine, Chinese Traditional; Mice; Mice, Inbred BALB C; Molecular Docking Simulation; RNA-Dependent RNA Polymerase; RNA, Viral; Viral Nonstructural Proteins; Virus Replication

Artemisinin, curcumin or quercetin, alone or in combination, were loaded in nutriosomes, special phospholipid vesicles enriched with Nutriose FM06®, a soluble dextrin with prebiotic activity, that makes these vesicles suitable for oral delivery. The resulting nutriosomes were sized between 93 and 146 nm, homogeneously dispersed, and had slightly negative zeta potential (around -8 mV). To improve their shelf life and storability over time, vesicle dispersions were freeze-dried and stored at 25 °C. Results confirmed that their main physico-chemical characteristics remained unchanged over a period of 12 months. Additionally, their size and polydispersity index did not undergo any significant variation after dilution with solutions at different pHs (1.2 and 7.0) and high ionic strength, mimicking the harsh conditions of the stomach and intestine. An in vitro study disclosed the delayed release of curcumin and quercetin from nutriosomes (∼53% at 48 h) while artemisinin was quickly released (∼100% at 48 h). Cytotoxicity assays using human colon adenocarcinoma cells (Caco-2) and human umbilical vein endothelial cells (HUVECs) proved the high biocompatibility of the prepared formulations. Finally, in vitro antimalarial activity tests, assessed against the 3D7 strain of Plasmodium falciparum, confirmed the effectiveness of nutriosomes in the delivery of curcumin and quercetin, which can be used as adjuvants in the antimalaria treatment. The efficacy of artemisinin was also confirmed but not improved. Overall results proved the possible use of these formulations as an accompanying treatment of malaria infections.

Topics: Adenocarcinoma; Adjuvants, Immunologic; Adjuvants, Pharmaceutic; Antimalarials; Artemisinins; Caco-2 Cells; Colonic Neoplasms; Curcumin; Endothelial Cells; Humans; Liposomes; Malaria; Quercetin

Deletion of tumor suppressor gene, lethal(2)giant larvae [l(2)gl], leads to brain tumor in Drosophila melanogaster at larval stage of development and severe brain dysplasia in mice. We have studied the effect of two potential antitumor drugs artemisinin and curcumin in the perspective of inhibiting l(2)gl brain tumor. Efficacies of these drugs are characterized morphologically by measuring brain sizes of untreated and treated larvae on the basis of tumor inhibition and anatomically by looking at the cellular patterning via antibody staining of the third instar Drosophila larval brains. Behavioral experiments were done in form of locomotion to correlate tumor inhibition with the revival of brain function and longevity assays to assess general health span. It was observed that both drugs show antitumor properties individually and in combination when larvae were treated with these drugs. We also found evidence for reactive oxygen species-mediated action of these drugs. Both the drugs when treated individually or together show better median life span and locomotory response. Although the efficacies of various treatments varied, overall, the positive effects of artemisinin and curcumin demonstrate a potential applicability of these drugs against brain tumor in higher organisms. It also paves a way for a simpler model system for screening such natural products for antitumor property.

Topics: Animals; Antineoplastic Agents; Artemisinins; Brain Neoplasms; Curcumin; Drosophila melanogaster; Drug Screening Assays, Antitumor; Longevity; Motor Activity; Reactive Oxygen Species

The therapeutic efficacies of novel liposomal delivery systems based on artemisinin or artemisinin-based combination therapy with curcumin have been investigated and reported in this study. The developed liposomal formulations had proper characteristics as drug carriers for parental administration in terms of particle size, polydispersity, encapsulation efficacy and ζ-potential. Their physical and chemical stabilities were also evaluated. Furthermore, the in vivo antimalarial activity of artemisinin-based liposomal formulations was tested in Plasmodium berghei NK-65 infected mice, a suitable model for studying malaria because the infection presents structural, physiological and life cycle analogies with the human disease. Artemisinin, alone or in combination with curcumin, was encapsulated in conventional and PEGylated liposomes and its in vivo performance was assessed by comparison with the free drug. Mice were treated with artemisinin at the dosage of 50 mg/kg/days alone or plus curcumin as partner drug, administered at the dosage of 100 mg/kg/days. Artemisinin alone began to decrease parasitaemia levels only 7 days after the start of the treatment and it appeared to have a fluctuant trend in blood concentration which is reflected in the antimalarial effectiveness. By contrast, treatments with artemisinin-loaded conventional liposomes (A-CL), artemisinin-curcumin-loaded conventional liposomes (AC-CL), artemisinin-loaded PEGylated liposomes (A-PL), artemisinin-curcumin-loaded PEGylated liposomes (AC-PL) appeared to have an immediate antimalarial effect. Both nanoencapsulated artemisinin and artemisinin plus curcumin formulations cured all malaria-infected mice within the same post-inoculation period of time. Additionally, all formulations showed less variability in artemisinin plasma concentrations which suggested that A-CL, AC-CL, A-PL and AC-PL give a modified release of drug(s) and, as a consequence, a constant antimalarial effect during time. In particular, A-PL seems to give the most pronounced and statistically significant therapeutic effect in this murine model of malaria. The enhanced permanency in blood of A-PL suggests the use of these nanosystems as suitable passive targeted carriers for parasitic infections; this strong effect of formulation is added up to the mechanism of action of artemisinin which acts in the erythrocyte cycle stage of human host as a blood schizonticide.

Topics: Animals; Antimalarials; Artemisinins; Chemistry, Pharmaceutical; Curcumin; Drug Carriers; Drug Stability; Drug Therapy, Combination; Female; Liposomes; Malaria; Mice; Mice, Inbred BALB C; Nanoparticles; Particle Size; Plasmodium berghei; Polyethylene Glycols

Artemisinin, a potent antimalarial drug derived from Artemisia annua L., and curcumin, a polyphenol extracted from the roots of Curcuma longa L., are reported to exert a synergistic antimalarial action, albeit manifesting a low bioavailability. In fact, both these molecules are poorly soluble in aqueous environments. In this study, we report a DOSY investigation of the solubilisation capacity of micelles of sodium dodecyl sulphate (SDS) for artemisinin and curcumin, individually and in combination. The aqueous solubility of artemisinin was enhanced approximately 25-fold by 40 mM SDS, and 50-fold by 81 mM SDS, while that of curcumin was increased to 2 mM by 81 mM SDS. In addition, we performed model studies on the use of the surface-active radical scavenger octanoyl-6-O-ascorbic acid (ASC8) to combine solubilisation with protection against oxidation for the chemically labile artemisinin. A 16-fold enhancement of artemisinin solubility was measured in a solution containing 40 mM SDS and 60 mM ASC8. Even after treatment with 60 mM hydrogen peroxide, more than a 30-fold excess, almost half the artemisinin remained, suggesting a potentially useful combination of the surface activity and antioxidant properties of the novel binary SDS:ASC8 system.

Topics: Antimalarials; Antioxidants; Artemisinins; Chemistry, Pharmaceutical; Curcumin; Diffusion; Hydrogen Peroxide; Magnetic Resonance Spectroscopy; Micelles; Oxidants; Oxidation-Reduction; Solubility; Surface-Active Agents

Recent studies have proposed curcumin as a potential partner for artemisinin in artemisinin combination therapies to treat malaria infections. The efficacy of curcumin alone and in combination with artemisinin was evaluated on a clone of Plasmodium chabaudi selected for artemisinin resistance in vivo. The addition of piperine as an enhancer of curcumin activity was also tested. Results indicated that curcumin, both alone and in combination with piperine had only a modest antimalarial effect and was not able to reverse the artemisinin-resistant phenotype or significantly affect growth of the tested clone when used in combination with artemisinin. This is in contrast with previous in vivo work and calls for further experimental evaluation of the antimalarial potential of curcumin.

Topics: Administration, Oral; Alkaloids; Animals; Anti-Infective Agents; Artemisinins; Benzodioxoles; Biological Availability; Curcumin; Drug Resistance; Drug Therapy, Combination; Malaria; Male; Mice; Parasitemia; Piperidines; Plasmodium chabaudi; Polyunsaturated Alkamides

Traditional medicines provide fertile ground for modern drug development, but first they must pass along a pathway of discovery, isolation, and mechanistic studies before eventual deployment in the clinic. Here, we highlight the challenges along this route, focusing on the compounds artemisinin, triptolide, celastrol, capsaicin, and curcumin.

Topics: Animals; Artemisinins; Capsaicin; Curcumin; Diterpenes; Drug Approval; Drug Evaluation, Preclinical; Epoxy Compounds; Humans; Medicine, Traditional; Pentacyclic Triterpenes; Phenanthrenes; Plant Preparations; Technology, Pharmaceutical; Triterpenes

Artemisinin and curcumin show an additive interaction in killing Plasmodium falciparum in culture. In vivo, 3 oral doses of curcumin following a single injection of alpha,beta-arteether to Plasmodium berghei-infected mice are able to prevent recrudescence due to alpha,beta-arteether monotherapy and ensure almost 100% survival of the animals.

Topics: Animals; Antimalarials; Artemisinins; Curcumin; Drug Therapy, Combination; Inhibitory Concentration 50; Malaria; Mice; Parasitemia; Plasmodium berghei; Plasmodium falciparum; Sesquiterpenes; Survival Analysis; Treatment Outcome