Concomitant L-Carnitine Supplementation and Exercise Training Affects Apoptosis in Male Rats

Background: Apoptosis is a defensive measure that removes dysfunctional cells. Exercise training has a broad spectrum of benefits that influence apoptosis and cell viability. L-carnitine (LCAR), a supplement nowadays, has shown beneficial effects against cell death. We investigated the simultaneous effect of exercise training (acute exercise [AE] and high-intensity interval training [HIIT]) and LCAR supplementation on the proteins involved in apoptosis. The animals were anesthetized twenty-four hours after the conclusion of the final training session. Methods: Forty-eight male Wistar rats (210±10 g) were assigned to six groups (n=8) as follows: Control, LCAR (200 mg/kg/d LCAR, IP), AE, HIIT, LCAR+AE, and LCAR+HIIT. The animals were anesthetized and sacrificed twenty-four hours after the last training session; the rats’ blood sample was collected, and the serum was separated. The serum Bcl-2 levels, as an anti-apoptotic factor, and caspase-3 and BAX, as proapoptotic factors, were measured using specific ELISA kits. Results: AE increased apoptosis, but HIIT’s effects were almost neutral. LCAR administration in groups that performed either AE or HIIT significantly attenuated apoptosis. However, in group 6 (LCAR+HIIT), the anti-apoptotic effects were noteworthy because LCAR+HIIT significantly increased Bcl-2 and reduced caspase-3 levels compared to the control group. Conclusion: HIIT improved cell viability through increasing Bcl-2 levels, and LCAR strengthened HIIT’s anti-apoptotic properties. AE increased proapoptotic proteins, and LCAR modified the elevated proapoptotic markers in the AE group. Therefore, LCAR may be considered a promising supplement against exercise-mediated injury. This study can be extended to humans to evaluate the beneficial effects of LCAR+HIIT and LCAR+AE.