Effects of apple extract on the mechanism of apoptosis during acetic acid-induced colitis in Wistar rats

Purpose The aim of this study was to evaluate the immunoreactivity of Fas-L, Fas, FADD (Fas-associated protein with death domain), Smac/DIABLO, apoptosis-inducing factor (AIF), cytochrome c, and cleaved caspase 3 in the colon of rats with colitis and treated with apple extract. Methods For this purpose, Wistar rats were submitted to the following experimental design: Group 1 (Sh) was kept as normal and received 1.0 mL of saline solution by intra-colonic injection. Group 2 (AE) only received the concentrated apple extract (CAE) treatment. Groups 3 (AA), 4 (CT), and 5 (PT) were subjected to the induction of experimental colitis by intra-colonic injection of 1 mL acetic acid (7%). Group 3 (AA) simulated as AA-colitis control. Group 4 (CT) was treated with CAE after AA-colitis induction for 7 days, and group 5 (PT) was treated 7 days before colitis induction and followed CAE treatment after colitis induction. The AE, CT, and PT groups received the CAE (1 mL) orally by gavage. All rats were euthanized on day 8 following the experiment. Results There were no significant statistical differences in the immunoreactivity of Fas-L, Fas, Smac/DIABLO, AIF, and cytochrome c. The expression of FADD in the PT group was similar to that of the AE group and three times greater than in the CT group. For this preventive group (PT), the expression of FADD was restored by apple extract. Conclusion Our results demonstrated that concentrated apple extract was able to interfere with either intrinsic or extrinsic apoptotic pathways in the colon of rats with colitis.