Background: The objective of the present study was to reveal patterns in the treatment of health conditions in a Quechua-speaking community in the Bolivian Andes based on plant use data from traditional healers and patient data from a primary health care (PHC) service, and to demonstrate similarities and differences between the type of illnesses treated with traditional and biomedical health care, respectively.

The in vitro and in vivo activities of a mixture of six oleane triterpene saponins, recovered from the methanolic extract of the leaves of the Vietnamese plant Maesa balansae (PX-6518), were evaluated against drug-sensitive visceral Leishmania strains. The in vitro 50% inhibitory concentration (IC 50 ) against intracellular Leishmania infantum amastigotes was 0.04 g/ml. The cytotoxic concentrations causing 50% cell death (CC 50 s) were about 1 g/ml in murine macrophage host cells and >32 g/ml in human fibroblasts (MRC-5 cell line). Evaluation in the Leishmania donovani BALB/c mouse model indicated that a single subcutaneous administration of 0.4 mg/kg at 1 day after infection reduced liver amastigote burdens by about 95% in all treated animals. If treatment was delayed until 14 days after infection, a dose of 1.6 mg/kg of body weight was required to maintain the same level of activity. Single 250-mg/kg doses of sodium stibogluconate (Pentostam) 1 and 14 days after infection produced comparable efficacies. A single dose of PX-6518 at 2.5 mg/kg administered 5 days before infection was still 100% effective in preventing liver infection, suggesting a particularly long residual action. Spleen and bone marrow could not be cleared by PX-6518 nor sodium stibogluconate. PX-6518 did not show activity after oral dosing at up to 200 mg/kg for 5 days. This study concludes that triterpenoid saponins from M. balansae show promising in vitro and in vivo antileishmanial potential and can be considered as new lead structures in the search for novel antileishmanial drugs.Leishmaniasis is a growing health problem in many parts of the world, with about 350 million people living in areas of disease endemicity and about 2 million new cases each year (10). As for the other neglected diseases of poverty (28), treatment options for leishmaniases are limited and rely on pentavalent antimonials as first-line and amphotericin B and pentamidine as second-line drugs (8, 13). However, the excessively high cost of liposomal amphotericin B precludes any practical use (41). An important step forward was the recent approval of miltefosine as the first oral treatment for visceral leishmaniasis (37).Given the prospect that antileishmanial vaccines may not become available in the near future (14), the search for better drugs should be continued, whereby natural products may offer an unlimited source of chemical diversity for identification of new drug templates (1, 5, 11).During a random drug screening program, the methanolic extract of the leaves of the Vietnamese plant Maesa balansae Mez. (Myrsinaceae) was found to possess strong antileishmanial potential (23), and pentacyclic triterpene saponins were identified as the active constituents (12). Saponins have been demonstrated in a large number of plant species, and very different biological activities have been described (16). Antileishmanial activity has been reported for Hedera (9, 31), Dracaena (26), and Yucca (29) saponins, but their value as drug candidates cannot be fully assessed, since in v...

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Daphnane orthoesters are the active ingredients of plant remedies from the Western, Chinese and African traditional medicine, and have provided important tools to investigate medicinally relevant processes like tumour promotion, apoptosis, neurotrophism, and VR1 activation. The occurrence, biological activity, and molecular pharmacology of these compounds will be reviewed.

Bioactivity-guided fractionation has led to the successful isolation of antiosteoporotic components, i. e., osthole, imperatorin and bergapten from an ethanolic extract of the fruits of Cnidium monnieri (L.) Cusson. Among them, osthole was determined as the major compound possessing antiosteoporotic activity. Further study showed that osthole not only promoted the proliferation and activity of alkaline phosphatase of osteoblasts in neonatal calvaria cultures, but also inhibited the bone resorption by decreasing the formation, differentiation and TRAP activity of osteoclasts derived from rat marrow cells.