Azadirachta indica extract-artesunic acid combination produces an increased cure rate of Plasmodium berghei-infected mice.

CONTEXT: Available artemisinin-combination therapies (ACTs) are expensive. Various traditional herbal remedies for malaria involve plants, proven scientifically to have antiplasmodial effects, e.g., Azadirachta indica A. Juss. (Meliaceae).

OBJECTIVE

Combination of an artemisinin-based compound and a medicinal herb extract will provide an indigenous alternative/herb-based ACT.

MATERIALS AND

METHODS

The in vivo schizontocidal activity of the crude aqueous extract of 100, 500, and 1000 mg/kg of A. indica fresh leaves (NCE) and 6, 15, and 20 mg/kg of artesunic acid were determined, alone and in combination, while keeping the dose of artesunic acid constant at 15 mg/kg, using the Peter's 4-day suppressive test and Swiss albino mice. The ED50 was calculated from the dose-response relationships. Percentage survival and cure were also determined.

RESULTS

The average yield of two extractions of NCE was 8.33 ± 1.67%. Combination of 1000 mg/kg of NCE and 15 mg/kg of artesunic acid, produced a significant reduction of parasitemia (96.87%), compared to 20 mg/kg of artesunic acid alone (68.14%). The combination had an ED50 of 0.58 mg/kg while that of artesunic acid alone was 8.814 mg/kg. The combinations of NCE with artesunic acid produced a cure, although the artesunic acid did not produce a cure in 30 d.

DISCUSSION: NCE increased the activity of artesunic acid in terms of reduction in parasitemia, and increased survival time and cure rate.

CONCLUSION

The combination of an artemisinin and aqueous extract of neem leaf is possible, providing a potentiated reduction of parasitemia, and increased cure rate.