Luc Van Puyvelde

Comparison of health conditions treated with traditional and biomedical health care in a Quechua community in rural Bolivia

BackgroundThe 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.MethodsA secondary analysis of plant use data from semi-structured interviews with eight healers was conducted and diagnostic data was collected from 324 patients in the community PHC service. Health conditions were ranked according to: (A) the percentage of patients in the PHC service diagnosed with these conditions; and (B) the citation frequency of plant use reports to treat these conditions by healers. Healers were also queried about the payment modalities they offer to their patients.ResultsPlant use reports from healers yielded 1166 responses about 181 medicinal plant species, which are used to treat 67 different health conditions, ranging from general symptoms (e.g. fever and body pain), to more specific ailments, such as arthritis, biliary colic and pneumonia. The results show that treatment offered by traditional medicine overlaps with biomedical health care in the case of respiratory infections, wounds and bruises, fever and biliary colic/cholecystitis. Furthermore, traditional health care appears to be complementary to biomedical health care for chronic illnesses, especially arthritis, and for folk illnesses that are particularly relevant within the local cultural context. Payment from patients to healers included flexible, outcome contingent and non-monetary options.ConclusionTraditional medicine in the study area is adaptive because it corresponds well with local patterns of morbidity, health care needs in relation to chronic illnesses, cultural perceptions of health conditions and socio-economic aspects of health care. The quantitative analysis of plant use reports and patient data represents a novel approach to compare the contribution of traditional and biomedical health care to treatment of particular health conditions.

In Vitro and In Vivo Activities of a Triterpenoid Saponin Extract (PX-6518) from the Plant Maesa balansae against Visceral Leishmania Species

ABSTRACT 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 (IC50) against intracellular Leishmania infantum amastigotes was 0.04 μg/ml. The cytotoxic concentrations causing 50% cell death (CC50s) were about 1 μg/ml in murine macrophage host cells and >32 μg/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.

Comparative Activities of the Triterpene Saponin Maesabalide III and Liposomal Amphotericin B (AmBisome) against Leishmania donovani in Hamsters

ABSTRACT Maesabalide III (MB-III), an oleane triterpene saponin isolated from the Vietnamese plant Maesa balansae, is a new antileishmanial lead compound whose activity against Leishmania donovani (MHOM/ET/67/L82) in groups of five golden hamsters was evaluated after administration of a single subcutaneous dose on either day 1 (prophylactic treatment) or day 28 (curative treatment) after infection. Liposomal amphotericin B (AmBisome), administered intravenously at 5 mg/kg of body weight, was used as the reference drug. Amastigote burdens in liver, spleen, and bone marrow were determined either 7 days (early effects) or 56 days (late effects) after treatment. Prophylactic administration of MB-III at 0.2 mg/kg reduced liver amastigote burdens by 99.8 and 83% within 7 and 56 days after treatment, respectively. In the latter group, however, all animals became ill and some died. Both MB-III at 0.8 mg/kg and liposomal amphotericin B were 100% effective against liver stages, but clearance from the spleen and bone marrow was not achieved. Curative administration of MB-III at 0.2 and 0.4 mg/kg was not protective, as no survivors were left at the termination of the experiment on day 84. Despite the high level of reduction of the liver amastigote burden after treatment with MB-III at 0.8 mg/kg (94.2%) or liposomal amphotericin B (99.4%), clinical protection could not be obtained in either group, with two deaths occurring and the residual liver burdens persisting. It is concluded that administration of a single dose of MB-III at 0.8 mg/kg has efficacy potential comparable to that of a single dose of liposomal amphotericin B at 5 mg/kg and is therefore considered a promising new antileishmanial lead compound. However, multiple-dose pharmacological, toxicological, and pharmacokinetic studies are still needed before it can become a valid drug candidate for development.

Daphnane-Type Diterpene Orthoesters and their Biological Activities.

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.

New α-pyrones from Iboza riparia

Abstract The structures for umuravumbolide, 5,6-dihydro-6-(3-acetoxy-1-heptenyl)-2-pyrone, a new α-pyrone from Iboza riparia (Labiatae) and its corresponding deacylated product have been established. Deacetylboronolide was also isolated and identified by different spectroscopic techniques.

Active principles of Tetradenia riparia. I. Antimicrobial activity of 8(14),15-sandaracopimaradiene-7α,18-diol

Tetradenia riparia is one of the most popular medicinal plants in Rwanda. Previously, several new substances have been isolated from the leaves of this plant, including a new diterpene diol, i.e. 8(14),15-sandaracopimaradiene-7 alpha,18-diol. This new diterpene diol exhibits significant antimicrobial activity against several bacteria and fungi. The minimum inhibitory concentration (MIC) of the substance for microorganisms which were inhibited ranged from 6.25 to 100 micrograms/ml.

Screening of medicinal plants of rwanda for acaricidal activity

A series of 108 samples from 42 medicinal plants of Rwanda have been screened for acaricidal activity against the female tick Rhipicephalus appendiculatus. Two plants, Solanum dasyphyllum (fruits) and Neorautanenia mitis (roots) showed apparent acaricidal activity in the petroleum ether fraction.

Screening of Rwandese medicinal plants for anti-trichomonas activity

A series of 30 medicinal plants used in Rwandese traditional medicine has been screened for anti-trichomonas activity against the protozoan Trichomonas vaginalis. Seventeen plants showed anti-trichomonas activity.

1′,2′-Dideacetylboronolide, an α-pyrone from Iboza riparia

The structural elucidation of 1′,2′-dideacetylboronolide, 5,6-dihydro-6-(3′-acetoxy-1′,2′-dihydroxyheptyl)2-pyrone, a new α-pyrone isolated from the leaves of Iboza riparia has been performed. Additionally, three sterols, sitosterol, stigmasterol and campesterol, have been identified in this species.

Neurotrophic and Antileukemic Daphnane Diterpenoids from Synaptolepis kirkii

Biological assay guided fractionation of a dichloromethane extract of Synaptolepis kirkii led to the isolation of four new and five known daphnane-type diterpene orthoesters, whose structure was established by spectroscopic data. Full spectroscopic data of the new and known natural products are reported here for the first time. Pronounced neurotrophic and substantial antileukaemia activities of these compounds were found in in vitro assays.