Spleen protective role, Antiplasmodial and Antioxidant activity of Polyalthia longifolia in mice infected with Plasmodium berghei parasite

• Reduced parasitaemia was observed after treatment of malaria mice with ethanol extract of P. longifolia (EEPL). • EEPL reduces oxidative stress in the spleens of malaria mice when compared to standard drug (Lonart). • There was significant increase in antioxidant indices malaria infected mice treated with EEPL. • Degenerated spleens cells were regenerated in malaria mice treated with EEPL. Malaria is a potentially fatal illness that is mostly prevalent in tropical regions. Finding new compounds with antimalarial action can be facilitated through investigating medicinal plants. This study is aimed at determining the antioxidant properties, antimalaria and spleen protective role of Polyalthia longifolia in mice infected with Plasmodium berghei . Total of thirty six (36) Swiss albino BALB/c mice were used for the study and 30 were inoculated with P. berghei (NK 65 strain) malarial parasite. Graded doses (100,200 and 400mg/kg/day) of ethanol extract of P. longifolia (EEPL) leaves and standard drug, Artemether and Lumefantrine (lonart) (2 mg/kg/day) were used for the treatment of malaria mice. One-way ANOVA was used for statistical analysis, and values were presented as percentage change ± SD. The results of this study showed that treatment of malaria with 100, 200 and 400 mg/kg/day of EEPL, and Artemether and Lumefantrine (lonart) (2 mg/kg/day), steadily reduced parasitaemia of malaria mice. There was significant increase in GSH, GPx, CAT, SOD, TAC and ferritin in the spleen across treatment groups when compared with control. The spleens of malaria mice exhibited structural disorganization and remodelling which were regularised after treatment with the EEPL and lonart. However, treatment with the standard drug (Lonart) had the highest survival rate, followed by the 400 mg/kg/day EEPL. In conclusion, EEPL treatment was able to control the macrophage response of mice erythrocytes infected with P. berghei . To pinpoint the exact mechanism causing these alterations, more research, such as characterizing the bioactive chemicals, might be required.