Senna plant generates reactive oxygen species (ROS) and induces apoptosis in Hymenolepis diminuta.

Like mammalian cells, helminth parasites are equipped with an array of enzymatic anti-oxidant system which has an adaptive strategy to cope up with several conditions of stress that arise from host immune response or drug treatment. Earlier, we had reported that three species of Senna, viz. S. alata, S. alexandrina and S. occidentalis leaf extracts caused severe morphological and biochemical alterations in the zoonotic parasite Hymenolepis diminuta. To understand whether the leaf extracts of the three species of Senna have any effect on the enzymatic anti-oxidant system in H.diminuta or not, the present study was investigated on the mechanism of action of these leaf extracts on the anti-oxidant system of the parasite. The viability of the parasite was assessed by MTT reduction assay, chromatin condensation through Hoechst staining of tissue and DNA fragmentation assay, and the oxidative enzymes of the parasite were estimated biochemically. Activity of superoxide dismutase, catalase, glutathione S- transferase and glutathione peroxidase were found to be increased in all the treated parasites from that of the control, with S. alata showed the highest increased amongst the three plant species in all the enzymes, at 331.0 %, 215.4 %, 85.4 % and 65.5 % respectively. Upliftment of apoptotic protein CED-3, CED-4 and EGL-1 and down regulation of anti-apototic protein CED-9 was visualised in all treated paraites. The redox imbalance triggered by these leaf extracts resulted in the activation of apoptotic pathway that led to death of the parasite. Our results demonstrated that the leaf extracts of the three Senna plant species could open new insight for an affordable natural anthelmintic with high efficacy and less toxicity.