Carpolobia lutea G. Don (Polygalaceae) Inhibits Inflammation and Oxidative Stress in an Acetic Acid Induced Model of Rat Colitis.

Carpolobia lutea G. Don (CL) is used in folk medicine for the treatment of inflammatory disorders. Effort in this study is to evaluate the beneficial effect of the aqueous-methanol extract of leaf of CL in a rat model of acetic acid induced colitis. Male Wistar rats were distributed into 6 groups of 7 rats each; non colitic, untreated colitic and colitic rats treated with graded doses of CL (100-800 mg/kg). Rats were pre-treated for 2 days before colitis induction and thereafter for 7 days post colitic induction. 24 h after the last treatment, animals were sacrificed and colonic inflammation was evaluated both macroscopically and biochemically. Macroscopic damage score, weight/length ratio, myeloperoxidase (MPO) activity and tumor necrotic factor alpha (TNF-α) levels, were significantly higher in untreated colitic rats in comparison with non colitic rats (P<0.05). Treatment with CL significantly reduced the macroscopic damage scores, neutrophil infiltration (MPO activity) and TNF-α level (P<0.05). In addition, C. lutea significantly prevented depletion of colonic GSH and (SOD) levels (P<0.05). It appears that the beneficial effect of methanol extract of C. lutea leaf observed in this study is dose dependent and is related to its antioxidant and anti-inflammatory activity.

In vivo Antimalarial Activities of Russelia Equisetiformis in Plasmodium Berghei Infected Mice.

The rising problem of resistance to most commonly used antimalarials remains a major challenge in the control of malaria suggesting the need for new antimalarial agents. This work explores the antiplasmodial potential of ethanol extract of Russelia equisetiformis in chloroquine Plasmodium berghei infected mice. Swiss albino mice were intraperitoneally infected with chloroquine-resistant P. berghei (ANKA). Experimental mice were treated for four days consecutively with graded doses of plant extracts and standard antimalarial drugs (artesunate and chloroquine) at a dose of 10 mg/kg body weight used as control. The extract showed a dose-dependent activity in the chemosuppression of P. berghei parasites by 31.6, 44.7, 48.4 and 86.5% at doses of 100, 200, 400 and 800 mg/kg, while chloroquine (10 mg/kg) and artesunate produced 59.4 and 68.4%, respectively. The extract showed a significant decrease in parasitaemia (P<0.05). The level of parasitemia and decrease in weight in all the treated groups was significantly lower (P<0.05) compared with the infected but untreated mice. The plant extract was devoid of toxicity at the highest dose tested (5000 mg/kg). The study concluded that the ethanol extract of R. equisetiformis possesses antimalarial effect, which supports the folk medicine claim of its use in the treatment of malaria.

In vitro antimicrobial activity of crude ethanol extracts and fractions of Terminalia catappa and Vitex doniana.

BACKGROUND: The spread of microorganisms resistant to some antimicrobial agents necessitates the need to search for novel and effective antimicrobial agents. In this study, the antimicrobial activity of Terminalid catappa Linn. (Combretaceae) and Vitex doniana Sweet. (Verbenaceae), two Nigerian medicinal plants used in folk medicines for the management of various ailments related to microbial infections were evaluated. OBJECTIVES: To evaluate the antimicrobial activity of the crude ethanol extracts and fractions of the leaves and stem bark of T. catappa and V. doniana. METHODOLOGY: Four crude ethanol extracts and 16 (n-hexane, ethylacetate, n-butanol and aqueous) fractions of leaves and stem bark of T. catappa and V doniana were evaluated for in vitro antimicrobial activity against fifteen (15) strains of bacteria and fungi. The antimicrobial activity was determined in a 96-well plate using a resazurin based broth microdilution method. Two standard antimicrobial drugs ampicillin and nystatin were included as positive control. RESULTS: The butanoL fraction of stem bark of T. catappa and ethanol crude extract of leaf of V don iana displayed the highest antibacterial activity with similar minimum inhibitory concentration (MIC) value of 93.75 microg/mL against S. aureus and B. subtilis. Furthermore, the ethyl acetate fraction of stem bark of T. catappa showed the highest antifungal activity with MIC of 187.5 microg/mL against A. sydowi. Amp icillin had MIC of 15.6 and 31.3 microg/mL against S. aureus and B. subtili, respectively while nystatin produced MIC of 3.9 microg/mL against A. sydowi. CONCLUSION: Termninalia catappa and Vitex doniana may serve as useful sources of plant derived antimicrobial agents.

Amodiaquine-Ciprofloxacin: a potential combination therapy against drug resistant malaria.

Emergence of malaria parasites resistant to artemisinin necessitates the need for development of new antimalarial therapies. Ciprofloxacin (CFX) a second generation quinolone antibiotic possesses some antimalarial activities. We investigated the in vivo antimalarial activities of CFX in combination with amodiaquine in mice infected with chloroquine-resistant Plasmodium berghei ANKA. Animals were treated orally with 80 or 160 mg kg-1 body weight of CFX alone given twice daily or in combination with amodiaquine (AQ) 10 mg kg-1 body weight. Parasitological activity and survival of the animals were assessed over 21 days. Peak parasitaemia in the untreated control group was 72.51%. Treatment with AQ alone resulted in clearance of parasitaemia by day 4 while treatment with CFX 80 and 160 mg kg-1 alone suppressed parasitaemia by 13.94-54.64% and 35.6-92.7%, respectively. However, the combination of CFX with AQ significantly enhanced response of infection in the animals to treatment (P < 0.05) resulting in complete resolution of parasitaemia throughout follow up period with CFX 160 mg kg-1, delayed recrudescence time with CFX 80 mg kg-1 and significant increase in survival rate of the animals. The results demonstrate beneficial interaction between AQ and CFX which may provide a clinically relevant antimalarial/antibiotic therapeutic option in the management of malaria.

Cajachalcone: An Antimalarial Compound from Cajanus cajan Leaf Extract.

Cajanus cajan L, a member of the family Fabaceae, was identified from the Nigerian antimalarial ethnobotany as possessing antimalarial properties. The bioassay-guided fractionation of the crude methanol extract of C. cajan leaves was done in vitro using the multiresistant strain of Plasmodium falciparum (K1) in the parasite lactate dehydrogenase assay. Isolation of compound was achieved by a combination of chromatographic techniques, while the structure of the compound was elucidated by spectroscopy. This led to the identification of a cajachalcone, 2',6'-dihydroxy-4-methoxy chalcone, as the biologically active constituent from the ethyl acetate fraction. Cajachalcone had an IC50 value of 2.0 µ g/mL (7.4 µ M) and could be a lead for anti-malarial drug discovery.

In vitro cytotoxicity studies of 20 plants used in Nigerian antimalarial ethnomedicine.

Twenty plants identified and selected from Southwest and Middle belt Nigerian antimalarial ethnopharmacology were evaluated for in vitro cytotoxicity using the brine shrimp lethality assay. The methanol extracts of 20 plant samples from 11 plant families were subjected to the assay. Of the studied plants, Lippia multiflora and Morinda lucida bark were found to be cytotoxic, with LC(50) values of 1.1 and 2.6 microg/ml, respectively. The least toxic plant extract was Bridelia micrantha (LC(50) value >9.0 x 10(6) microg/ml). Most of the plants were found to be relatively non-toxic.

Efficacy of herbal remedies used by herbalists in Oyo State Nigeria for treatment of Plasmodium falciparum infections--a survey and an observation.

In the course of evaluating the contribution of phytomedicine to possible drug discovery of antimalarial drugs, an ethnomedical survey of specialized children traditional clinics was done. In the observational multi center study, efficacy of eight different herbal remedies, each consisting of 3-8 ingredients and administered by herbalists were investigated in clients enrolled in the six traditional clinics in Oyo (urban center) and Otu (rural center) of Oyo State, Nigeria. The clients, aged between six months and fifteen years with clinical symptoms of malaria were enrolled in the clinics of the herbalists, as their usual practice. Oral informed consents were obtained from their parents or guardians. Microscopic diagnosis of malaria infection was used to evaluate parasitaemia and validate efficacy of herbal remedies. Results of the analysis showed that, of the 163 clients of the herbalists, only 62 (30 from Oyo, 32 from Otu) had microscopically confirmed P. falciparum infection. Only results from 54 clients (29/30 (Oyo) and 25/32 (Otu) with P. falciparum infection could be evaluated. Plasmodium falciparum infection in 88% (23/29) of clients from Oyo responded to treatment with the herbal remedies while cure rate in clients from Otu was 42% (13/25). Parasite densities ranged from 171 to 53,613 parasites/microl blood and 87 to 36,209 parasites/microl blood in patients from Oyo and Otu respectively. The herbalists administered the remedies and Gossypium arboreum, Anarcadium occidentalis, Citrus medica, Phyllanthus amarus and Lippia multiflora were the main ingredients in the efficacious remedies. The herbalists gave detailed descriptions of each of the 8 herbal remedies proffered. The results confirm the efficacy of two of the eight herbal remedies, thereby validating the role of ethnomedicine as a possible source for the discovery of new chemotherapeutic agents in the treatment of P. falciparum malaria.