Publication:

Dose and time-dependent effect of orange juice on the antimalarial efficacy of artemether-lumefantrine, haematological, and antioxidant parameters

Background Orange juice (OJ) contains ascorbic acid, which has antioxidant properties that would be expected to protect against haemolytic effects and possibly interfere with the antimalarial mechanism of the artemisinin-based combination therapy. This study was designed to investigate the dose and time-dependent effect of OJ on the anti-malarial efficacy of artemether-lumefantrine (AL).

Methods Malaria was induced by inoculating plasmodium berghei parasite through the intraperitoneal route to albino mice. The infection was allowed to establish for 3 days, followed by treatment with AL alone, and its combination with graded doses of OJ. Separate doses of OJ were also administered to different groups.

Results Treatment with AL alone produced total parasite clearance (100%) in days 3 and 4 post-treatment. Co-administration of AL with graded doses of OJ showed significant (p<0.05) increase in parasitemia at OJ combination doses of 10, 8, and 6 ml/kg. Unlike antagonistic combination interaction exhibited by higher combination doses of OJ, lower combination doses of 4 and 2 ml/kg potentiated the antiplasmodial activity of AL. Compared to vehicle (malaria) control group, a significant (p<0.05) increase in PCV was achieved at combination OJ doses of 10, 8, 6, and 4 ml/kg. Combination doses of OJ at 10, 8, 6 ml/kg restored the catalase enzyme activity to the level that exist in uninfected naïve control group.

Conclusions OJ showed both antagonistic and beneficial interactions with AL at higher and lower doses, respectively. Combination of OJ with AL also has a beneficial effect in reducing both parasite and AL-induced oxidative stress.