Hepatoprotective and Antiplasmodial Effects of Ethanolic Leaf Extracts of Azadirachta indica and Cymbopogon citratus in Plasmodium berghei-Infected Mice

Abstract

Malaria remains a major public health concern in sub-Saharan Africa, with Nigeria among the most affected countries. This study evaluated the hepatoprotective and antiplasmodial effects of ethanolic leaf extracts of Azadirachta indica (EAI) and Cymbopogon citratus (ECC) in Plasmodium berghei-infected male Swiss albino mice. Forty mice were randomly assigned into eight groups (n=5). Group A served as uninfected control, Group B was infected but untreated, while Groups C-H were infected and subsequently treated with respective extracts. Groups C– H received varying doses of EAI, ECC, their combination, or a standard drug. Groups C and D received 100 mg/kg and 500 mg/kg EAI; Groups E and F received 100 mg/kg and 500 mg/kg ECC. Group G received Lonart® (standard antimalarial), and Group H received a combination of 500 mg/kg of both extracts. Treatments lasted 14 days. Infected groups showed minimal weight gain, while the uninfected control had significant increases. Relative liver weights were elevated in the untreated group but normalized in most treated groups. Serum AST and ALP levels were elevated in the malaria control group, while ALT levels were paradoxically reduced—possibly reflecting hepatic functional suppression. Extract-treated groups, especially the combination group, showed marked improvement in liver enzyme profiles. Parasitemia significantly declined by Days 7 and 14 in all treated groups, with the combination therapy yielding effects comparable to the standard drug. Histological analysis revealed lymphocytic infiltration and sinusoidal congestion in the malaria control group, which were ameliorated in extract-treated groups. These findings suggest dose-dependent hepatoprotective and antiplasmodial activities of EAI and ECC, likely due to their antioxidant and anti-inflammatory constituents.