The antimalarial compound qinghaosu (artemisinin) was tested in vitro for the ability to inhibit plaque formation by Toxoplasma gondii in fibroblasts. Qinghaosu at 0.4 microgram/ml for 5 days eliminated all plaques and microscopic foci of T. gondii. At 1.3 micrograms/ml for 14 days, qinghaosu completely eliminated T. gondii. Pretreatment of host cells or T. gondii with qinghaosu had no effect on T. gondii growth. There was no apparent toxicity to human fibroblasts in long-term studies.
Proceedings of the National Academy of Sciences of the United States of America
With >1 million deaths annually, mostly among children in sub-Saharan Africa, malaria poses one of the most critical challenges in medicine today. Although introduction of the artemisinin class of antimalarial drugs has offered a temporary solution to the problem of drug resistance, new antimalarial drugs are needed to ensure effective control of the disease in the future. Herein, we have investigated members of the methionine aminopeptidase family as potential antimalarial targets.
Toxoplasmosis, caused by the protozoan Toxoplasma gondii, is medically important and distributed worldwide. Currently available medications are limited in terms of efficacy and side effects. We synthesized novel, nonacetal, hydrolytically stable derivatives of artemisinin and showed that they inhibit the replication of Toxoplasma gondii in cell culture.
OBJECTIVES: Recent studies indicate that the anti-malarial agent artemisinin and its derivatives may exert an anti-inflammatory effect. In this study, we explored the effect of artesunate, an artemisinin derivative, on tumour necrosis factor (TNF)-alpha-induced production of interleukins, IL-1beta, IL-6 and IL-8, in human rheumatoid arthritis (RA) fibroblast-like synoviocytes (FLS), and further investigated the signal mechanism by which this compound modulates those cytokines' production.
OBJECTIVES: We sought to improve upon the usefulness of artemisinins as anti-Toxoplasma agents by synthesizing new unsaturated, carba derivatives and then testing them for in vitro efficacy against three steps of the lytic cycle of Toxoplasma gondii tachyzoites. METHODS: Novel derivatives of ART were synthesized and then tested for in vitro antiparasitic activity using T. gondii tachyzoites constitutively expressing beta-galactosidase and human fibroblast host cells.
BACKGROUND: Artesunate, an artemisinin-derived monomer, was reported to inhibit Cytomegalovirus (CMV) replication. We aimed to compare the in-vitro anti-CMV activity of several artemisinin-derived monomers and newly synthesized artemisinin dimers. METHODS: Four artemisinin monomers and two novel artemisinin-derived dimers were tested for anti-CMV activity in human fibroblasts infected with luciferase-tagged highly-passaged laboratory adapted strain (Towne), and a clinical CMV isolate. Compounds were evaluated for CMV inhibition and cytotoxicity.
We report that the artemisinin-derived dimer diphenyl phosphate (DPP; dimer 838) is the most selective inhibitor of human cytomegalovirus (CMV) replication among a series of artemisinin-derived monomers and dimers. Dimer 838 was also unique in being an irreversible CMV inhibitor. The peroxide unit within artemisinins' chemical structures is critical to their activities, and its absence results in loss of anti-CMV activities. Surprisingly, the deoxy dimer of 838 retained modest anti-CMV activity, suggesting that the DPP moiety of dimer 838 contributes to its anti-CMV activities.
The present study was undertaken to gain insights into the molecular mechanism of cell death (apoptosis) by guggulsterone, a constituent of Ayurvedic medicinal plant Commiphora mukul, using PC-3 human prostate cancer cells as a model. The viability of PC-3 cells, but not a normal prostate epithelial cell line (PrEC), was reduced significantly on treatment with guggulsterone in a concentration-dependent manner.
The present day lifestyle heavily depends on industrial chemicals in the form of agriculture, cosmetics, textiles and medical products. Since the toxicity of the industrial chemicals has been a concern to human health, the need for alternative non-toxic natural products or adjuvants that serve as antidotes are in high demand. We have investigated the effects of Ayurvedic herb Ashwagandha (Withania somnifera) leaf extract on methoxyacetic acid (MAA) induced toxicity.
Bacopa monniera L. (family Scrophulariaceae) (BM) is an Ayurvedic medicine, clinically used for memory enhancing, epilepsy, insomnia and as a mild sedative. In this work, the free radical scavenging capacity of a methanol extract of BM and the effect on DNA cleavage induced by H2O2 UV-photolysis was investigated. In addition, we examined whether this plant extract is capable of reducing the hydrogen peroxide-induced cytotoxicity and DNA damage in human non-immortalized fibroblasts. It showed a dose-dependent free radical scavenging capacity and a protective effect on DNA cleavage.
