Induction of caspase-3 activated DNase mediated apoptosis by hexane fraction of Tinospora cordifolia in EAT cells

Tinospora cordifolia (Guduchi) has been used for centuries for treating various ailments including cancer in Ayurvedic system of medicine. In this study, we report the mechanism of cell death exhibited by the hexane extract fraction of T. cordifolia (TcHf) against Ehrlich ascites tumor (EAT) in mice. Treatment of EAT bearing animals with TcHf resulted in growth inhibition and induction of apoptosis in a dose-dependent manner. TcHf induced the formation of apoptotic bodies, nuclear condensation, typical DNA ladder, activation of caspase-3, decreased cell number and ascites volume. We examined TcHf for its effect on proliferation and cell cycle progression in EAT cells. The results showed that TcHf inhibited the proliferation of EAT cells by blocking cell cycle progression in the G1 phase. In Western blot analysis, apoptosis in the EAT cells was associated with the constitutive expression of caspase activated DNase (CAD) in both nucleus and cytoplasm after TcHf treatment. Further more the expression of pro-apoptotic gene, Bax, was increased and the expression of anti-apoptotic gene, Bcl-2, was decreased in a time dependent manner by TcHf treatment. All results indicate that the hexane fraction of T. cordifolia is capable of inducing apoptosis in EAT cells in vivo.