Anti-inflammatory activity of selected plants used by the Ilkisonko Maasai, Kenya

Background: The Ilkisonko Maasai are a Kenyan pastoralist community that uses indigenous plants for the management of pain and inflammatory conditions such as arthritis. Objectives: The purpose of this study was to validate the use of plants for medicinal purposes by the Ilkisonko Maasai through testing for anti-inflammatory activity using the carrageenan-induced rat paw oedema assay. Methodology: The methanol extracts (400 mg/kg body weight) of Rhus natalensis (bark), Acacia drepanolobium (bark), Acacia nilotica (bark), Acacia reficiens (bark), Acacia robusta (bark), Grewia villosa (bark), Ximenia americana (bark and leaves) and Rhus vulgaris (leaves) were evaluated for in vivo anti-inflammatory efficacy using the carrageenan-induced rat paw oedema assay. Diclofenac (20 mg/kg body weight) was used as the positive control and paw volume was measured by a plethysmometer. Results: The maximum percentage inhibition (PI) of the extracts was observed as Grewia villosa (58.6% at 24 h), Rhus vulgaris (57.8% at 24 h), Acacia nilotica (55.5% at 1 h), Ximenia americana (54.5% at 1 h), Acacia drepanolobium (50.9% at 24 h), Acacia reficiens (47.6% at 1 h), Rhus natalensis (43.8% at 24 h) and Acacia robusta (37.4% at 24 h) (p < 0.05 for all PI). Diclofenac (20 mg/kg) showed a steady increase in PI from 1 h to 4 h with a maximum PI of 66.2% (p < 0.05) at 4 h and the lowest PI of 14.3% at 24 h. Conclusion: All extracts of the plants assessed exhibited anti-inflammatory activity at early phase of inflammation. Additionally, extracts of five plants, namely Rhus natalensis, Acacia drepanolobium, Acacia robusta, Grewia villosa and Rhus vulgaris showed anti-inflammatory activity at both early and late phases of inflammation. There is need for further studies to identify phytochemicals with active anti-inflammatory activity. Key words- Ilkisonko Maasai, carrageenan, inflammation, Rhus, Acacia, Grewia and Ximeni

Antioxidant and anti-inflammatory activities of selected medicinal plants from western Kenya

Background: Globally, the increase in the burden of diseases related to oxidative damage and inflammation, coupled with the high cost of medication and the side effects of these therapies necessitates a need for more effective, affordable and safer remedies. Thus there still exists a demand for new antioxidant and anti-inflammatory agents. Objectives: To screen selected medicinal plants from Kakamega County for their antioxidant and anti-inflammatory activities. Methodology: Seven medicinal plants used to treat ailments related to oxidative damage and inflammation were selected and extraction was carried out using methanol. Antioxidant activity was screened using 2, 2-diphenyl-1-picrylhydrazyl assay while carrageenan induced rat paw edema assay was used to screen for their anti-inflammatory activity. Results: The methanolic leaf extracts of Rhus vulgaris and Phyllanthus fischeri displayed good antioxidant activity with percentage inhibition of 71.4% and 66.7 % respectively. Furthermore, the methanolic leaf extract of Rhus vulgaris displayed significant anti-inflammatory activity while Phyllanthus fischeri had mild activity. Results were considered to be statistically significant when (P<0.05). Conclusion: These results support the use of Rhus vulgaris and Phyllanthus fischeri in traditional medicine to remedy oxidative damage and inflammatory related diseases. These two plants are potential sources of natural antioxidant and anti-inflammatory agents. Key words: Medicinal plants, Kakamega County, Antioxidant, Anti-inflammator

The Role of Natural Products in Drug Discovery and Development against Neglected Tropical Diseases

Endemic in 149 tropical and subtropical countries, neglected tropical diseases (NTDs) affect more than 1 billion people annually, including 875 million children in developing economies. These diseases are also responsible for over 500,000 deaths per year and are characterized by long-term disability and severe pain. The impact of the combined NTDs closely rivals that of malaria and tuberculosis. Current treatment options are associated with various limitations including widespread drug resistance, severe adverse effects, lengthy treatment duration, unfavorable toxicity profiles, and complicated drug administration procedures. Natural products have been a valuable source of drug regimens that form the cornerstone of modern pharmaceutical care. In this review, we highlight the potential that remains untapped in natural products as drug leads for NTDs. We cover natural products from plant, marine, and microbial sources including natural-product-inspired semi-synthetic derivatives which have been evaluated against the various causative agents of NTDs. Our coverage is limited to four major NTDs which include human African trypanosomiasis (sleeping sickness), leishmaniasis, schistosomiasis and lymphatic filariasis

Synthesis and biological evaluation of 4 arylcoumarin analogues as tubulin-targeting antitumor agents

International audienceThe synthesis of twenty-six 4-arylcoumarin analogues of combretastatin A-4 (CA-4) led to the identification of two new compounds (25 and 26) with strong cytotoxic activity. Both compounds had a high cytotoxic effect on a CA-4-resistant colon adenocarcinoma cell line (HT29D4). The compounds affected cell cycle progression characterized by a mitotic block. The activity of these compounds against microtubules both in vitro and in cells was examined and both compounds were found to potently inhibit in vitro microtubule formation via a sub-stoichiometric mode like CA-4. By immunofluorescence, it was observed that both compounds induced strong microtubule network disruption. Our results provide a strong experimental basis to develop new potent anti-tubulin molecules targeting CA-4-resistant cancer cells