Antioxidant and Anti-Inflammatory Activities of Extracts from Cassia alata, Eleusine indica, Eremomastax speciosa, Carica papaya and Polyscias fulva Medicinal Plants Collected in Cameroon

Background: The vast majority of the population around the world has always used medicinal plants as first source of health care to fight infectious and non infectious diseases. Most of these medicinal plants may have scientific evidence to be considered in general practice. Objective: The aim of this work was to investigate the antioxidant capacities and anti-inflammatory activities of ethanol extracts of leaves of Cassia alata, Eleusine indica, Carica papaya, Eremomastax speciosa and the stem bark of Polyscias fulva, collected in Cameroon. Methods: Chemiluminescence was used to analyze the antioxidant activities of plant extracts against hydrogen peroxide or superoxide anion. Comet assays were used to analyze the protection against antioxidant-induced DNA damage induced in white blood cells after treating with hydrogen peroxide. Flow cytometry was used to measure cd T cells proliferation and anti-inflammatory activity of cd T cells and of immature dendritic cells (imDC) in the presence of different concentrations of plant extracts. Results: Ethanol extracts showed strong antioxidant properties against both hydrogen peroxide and superoxide anion. Cassia alata showed the highest antioxidant activity. The effect of plant extracts on cd T cells and imDC was evidenced by the dose dependent reduction in TNF-a production in the presence of Cassia alata, Carica papaya, Eremomastax specios