Antimalarial and safety evaluation of Pluchea lanceolata (DC.) Oliv. & Hiern: In-vitro and in-vivo study

Ethnopharmacological relevance: Many of the effective therapeutic strategies have been derived from ethnopharmacologically used natural products. Pluchea lanceolata is an herb employed in Indian folk medicine for malaria like fever but it lacks proper pharmacological intervention. Aim of the study: To evaluate antimalarial and safety profile of Pluchea lanceolata: an in-vitro, in-vivo for its ethnopharmacological validation. Materials and methods: Methanol, butanol, ethyl acetate, chloroform, hexane extracts and its isolate, taraxasterol acetate (TxAc) were obtained from air dried aerial part of Pluchea lanceolata. These were tested in-vitro against chloroquine-sensitive strain of Plasmodium falciparum NF54 by measuring the parasite specific lactate dehydrogenase activity. The most potent hexane extract and TxAc were further validated for in-vivo antimalarial and safety evaluation. TxAc, a pentacyclic-triterpene isolated from the most active fraction was further evaluated with special emphasis on inflammatory mediators involved in malaria pathogenesis. Murine malaria was induced by intra-peritoneal injection of Plasmodium berghei infected red blood cells to the male Swiss inbred mice. Mice were orally treated following Peters 4-Day suppression test. In-vivo antimalarial efficacy was examined by evaluating the parasitaemia, percent survival, mean survival time, blood glucose, haemoglobin and pro-inflammatory mediators involved in malaria pathogenesis. Results: Hexane extract and TxAc showed promising antimalarial activity in-vitro and in-vivo condition. TxAc attributed in inhibition of the pro-inflammatory cytokines as well as afford to significant increase in the blood glucose and haemoglobin level when compared with vehicle treated infected mice. We have not observed the synergistic action of combinations of chloroquine and TxAc from our experimental results. In-vitro and in-vivo safety evaluation study revealed that hexane extract is non toxic at higher concentration. Conclusion: Present study further validates the ancient Indian traditional knowledge and use of Pluchea lanceolata as an antimalarial agent. Study confirms the suitability of Pluchea lanceolata as a candidate for further studies to obtain a prototype for antimalarial medicine. (C) 2013 Elsevier Ireland Ltd. All rights reserved.