Effects on the Phagocytosis Modulation of Stems Extract and Triterpenes from Gouania longipetala (Hemsl.), A Plant of The Cameroonian Pharmacopeia

Article history: Received 23 December 2018 Accepted 07 March 2019 Available online 17 April 2019 Immunomodulatory therapy is now being recognized as an alternative to conventional chemotherapy for a variety of disease conditions, involving the impaired immune response of the host. The goal of this study is to valorize Gouania longipetala (Hemsl.) like potential source of drugs against immune system dysfunction. This medicinal plant is commonly used in the Cameroonian pharmacopeia to cure a lot of diseases including inflammatory diseases. In this work, we evaluated the immunomodulation properties of infused stems extract (GLE) and triterpenes from G. longipetala (Hemsl.), with respect to the phagocytosis. GLE was obtained by infusion of dry bark powder in water and the triterpenes were isolated after fractionation of GLE in solvent systems following by column chromatography. The structure elucidation of isolated compounds was based on analysis of spectroscopic data including 1Dand 2D-NMR. The immunomodulation activity was evaluated by two methods. Firstly, the capacity of GLE and triterpenes to modulate phagocytic activity of polymorphonuclear (PMNs) cells was assessed in vitro against Candida albicans. Secondly, the ability of GLE to modulate reticuloendothelial system was investigated in vivo on wistar rats by carbon clearance test. Two triterpenes were isolated, alphitolic and epigouanic acids. The stimulation percentage of PMNs by plant extracts was ranged between 4.25 and 42.55% with GLE and between 14.89 and 46.80% with alphitolic acid. Epigouanic acid show biphasic activity profile, with stimulation of phagocytic activity of PMNs cells at lower concentrations and suppression effects at higher concentrations. In vivo test showed that GLE liberates the glutathione particles from animal’s liver and enhance the phagocytic activity by stimulating the reticuloendothelial system. The phagocytic index obtained was ranged between 0.020 ± 0.004 and 0.074 ± 0.006. The results obtained from this study show that extract from G. longipetala (Hemsl.) modulate phagocytic activity and would be therefore the potential sources of drugs against immunological disorders.