Antiplasmodial and Hepatoprotective Potentials of Certain Traditional Antimalarial Remedies Used in Nigeria

This study was performed to evaluate the antiplasmodial and hepatoprotective activities of aqueous leaves and stem bark extract of selected medicinal plants (Azadirachta indica, Khaya senegalensis, Parquetina nigrescens, and Citrus paradisi) in Plasmodium berghei infected mice and to document the components of these plants. The selected plants were marcerated in distilled water. Mice were inoculated with chloroquine sensitive NK 65 P. berghei for each test. Mice were treated with 100 mg/kg of extracts and 5 mg/kg chloroquine (positive control) and distilled water only. Blood films were prepared on slides, stained in Giemsa and examined for number of parasiteamia using microscope. Alkaline phosphatase (ALP), Gamma-glutamyltransferase (GGT), and Alanine aminotransferase (ALT) in serum were determined using standard laboratory procedure. Photomicrographs of liver sections were also determined to examine the histoarchitecture of this organ of biotransformation. Gas Chromatography system was used to determine the chemical profile of the extracts. The aqueous crude extracts of A. indica, K. senegalensis, C. paradisi leaves and stem bark at 100 mg/kg significantly (p< 0.05) inhibited the parasite with varying percentage in the curative, suppressive, and prophylactic tests. However there was no significant (p< 0.05) reduction in parasitaemia load in the prophylactic test for P. nigrescens. The histopathological studies of the liver sections showed that some of the extracts had significant (p< 0.05) hepatoprotective activity which was in close correlation with the activities of the liver enzymes results. The Gas Chromatographical analyses also revealed many phytochemicals, lipids and essential oils which could be responsible for the hepatoprotective effect of the extracts. These findings provide some justification for the use of the selected plants in the treatment of malaria in Nigeria. Therefore, further studies are ongoing to study the mechanism of action of some of the identified components.