Anti-atherogenic and anti-ischemic potentials of Croton membranaceus observed during sub-chronic toxicity studies.

BACKGROUND: Croton membranaceus (CM) is used for benign prostate hyperplasia treatment. OBJECTIVE: Sub-chronic toxicity studies are non-existent and provided the basis for this study. MATERIALS AND METHODS: 90 days oral administration of a low dose (LD) (30 mg/kg b. wt.), medium dose (MD) (150 mg/kg b. wt.), and high dose (HD) (300 mg/kg b. wt.) CM aqueous root extract to 3 groups (n=6 each) of male Sprague-Dawley rats, alongside a control group, was undertaken. Urinalysis, hepato-renal function tests, lipid profile, cardiac enzymes, and routine hematology tests were performed. RESULTS: Triglyceride levels (C=1.05±0.19, LD=0.64±0.08, MD=0.55±0.04, HD=0.50±0.02 mmol/L) were significantly reduced (P<0.05). Very low density lipoprotein (C=0.48±0.09, LD=0.29±0.04, MD=0.25±0.02, HD=0.23±0.01 mmol/L) decreased significantly (P<0.05). Cardiac enzymes-creatinine kinase (C=568±172, LD=315±79, MD=441±209, HD=286±81 IU/L) decreased markedly (P<0.05) alongside lactate dehydrogenase (C=2675±875, LD=1667±1229, MD=1186±442, HD=855±239 IU/L) (P<0.05). CONCLUSION: C. membranaceus aqueous root extract is non-toxic but demonstrates anti-atherogenic and anti-ischemic potentials.

Extracts of Euphorbia hirta Linn. (Euphorbiaceae) and Rauvolfia vomitoria Afzel (Apocynaceae) demonstrate activities against Onchocerca volvulus microfilariae in vitro.

BACKGROUND: Onchocerciasis transmitted by Onchocerca volvulus is the second major cause of blindness in the world and it impacts negatively on the socio-economic development of the communities affected. Currently, ivermectin, a microfilaricidal drug is the only drug recommended for treating this disease. There have been speculations, of late, concerning O. volvulus resistance to ivermectin. Owing to this, it has become imperative to search for new drugs. World-wide, ethnomedicines including extracts of Euphorbia hirta and Rauvolfia vomitoria are used for treating various diseases, both infectious and non-infectious. METHOD: In this study extracts of the two plants were evaluated in vitro in order to determine their effect against O. volvulus microfilariae. The toxicity of the E. hirta extracts on monkey kidney cell (LLCMK2) lines was also determined. RESULTS: The investigations showed that extracts of both plants immobilised microfilariae at different levels in vitro and, therefore, possess antifilarial properties. It was found that all the E. hirta extracts with the exception of the hexane extracts were more effective than those of R. vomitoria. Among the extracts of E. hirta the ethyl acetate fraction was most effective, and comparable to that of dimethanesulphonate salt but higher than that of Melarsoprol (Mel B). However, the crude ethanolic extract of E. hirta was found to be the least toxic to the LLCMK2 compared to the fractionated forms. CONCLUSIONS: Extracts from both plants possess antifilarial properties; however, the crude extract of E. hirta was found to be least toxic to LLCMK2.

Effectiveness and safety assessment of Mist Tonica, a herbal haematinic.

Anaemia is a widespread public health problem, and in Ghana it is the fourth leading cause of hospital admissions and the second factor contributing to death. Mist Tonica, an herbal haematinic produced by the Centre for Scientific Research into Plant Medicine (CSRPM), Ghana, was assessed for its effectiveness and safety in humans after Ethics Committee approval. Clinically established anaemic-patients aged, 13 years and above, with haemoglobin levels less than 11.5 g/dl and 13.5 g/dl for females and males respectively were treated with Mist Tonica, 8.96 g/40 mls three times daily for two weeks. The mean haemoglobin rise per week caused by Mist Tonica was 1.92 (0.76) g/dl, range (1.66-2.55) g/dl/week and over 88% of the patients on Mist Tonica had their appetite for food improved. Haematological profile, liver and kidney functions were not adversely affected by Mist Tonica. Results of the study suggest that Mist Tonica is an effective and safe herbal haematinic.

New dammarane and malabaricane triterpenes from Caloncoba echinata.

Three novel triterpenes, (11R,20R)-11,20-dihydroxy-24-dammaren-3-one (1), (17S,20R,24R)-17,25-dihydroxy-20,24-epoxy-14(18)-malabaricen-3-one (2), and (17R,20S,24R)-17,25-dihydroxy-20,24-epoxy-14(18)-malabaricen-3-one (3), were isolated from leaves of Caloncoba echinata. The structures were established using mainly 800 MHz NOESY and HMBC connectivities. The absolute stereochemistry of C-11 in 1 and that of C-17 in 2 were established by the Mosher method. The stereochemistry of the side chains of the malabaricanes is compatible with their biosynthesis by a cascade opening of diepoxides. The isolated triterpenes inhibited growth of Plasmodium falciparum parasites in vitro apparently via incorporation into erythrocyte membrane, as suggested by transformation of erythrocytes into stomatocytes at a concentration level at which the growth inhibition was observed.

Antiplasmodial compounds from Cochlospermum tinctorium.

Fractionation of an ethanol extract of roots of Cochlospermum tinctorium afforded five compounds: 3-O-E-p-coumaroylalphitolic acid (1), cochloxanthin (2), dihydrocochloxanthin (3), alphitolic acid (4), and 1-hydroxytetradecan-3-one (5). This is the first example of a 1-hydroxyalkan-3-one obtained from plant material after gentle workup. The antiplasmodial activities of the compounds were determined, and the IC(50) value of 3-O-E-p-coumaroylalphitolic acid was 2.3 microM.

Possible artefacts in the in vitro determination of antimalarial activity of natural products that incorporate into lipid bilayer: apparent antiplasmodial activity of dehydroabietinol, a constituent of Hyptis suaveolens.

Dehydroabietinol isolated from Hyptis suaveolens (L.) Poit. was found to inhibit growth of chloroquine-sensitive as well as chloroquine-resistant strains of Plasmodium falciparum cultivated in erythrocytes in vitro (IC 50 26-27 microM). However, erythrocytes exposed to dehydroabietinol were transformed in a dose-dependent manner towards spherostomatocytic forms with concomitant formation of endovesicles, as disclosed by transmission electron microscopy. The erythrocyte shape alterations caused by dehydroabietinol correlated well with its apparent IC 50 value. Thus, dehydroabietinol incorporates into the erythrocyte membrane, and since invasion and survival of Plasmodium parasites is known to depend on the function of the erythrocyte membrane, the observed antiplasmodial effect of dehydroabietinol is presumably an indirect effect on the host cell. Because of these findings, microscopic investigations should be generally used to support claims of antimalarial effects of apolar natural products.