Thymoquinone and aerobic exercise mitigate HFpEF-induced cardiac injury via Apaf1/Cycs axis regulation

Zuowei Pei^*Shan GaoJin YangChang LiuYanyan Pan

• Dalian Municipal Central Hospital, Dalian, China

Heart failure with preserved ejection fraction (HFpEF) is a common clinical syndrome associated with substantial morbidity and mortality. This study explores the synergistic cardioprotective effects of thymoquinone (TQ) and aerobic exercise in HFpEF models, with a particular emphasis on the Apaf1/Cycs-mediated apoptotic pathway. Male C57BL/6J mice were randomly divided into five groups: Control, HFpEF, HFpEF + TQ, HFpEF + exercise, and HFpEF combined with TQ and exercise. HFpEF was induced over a 10-week period using a high-fat diet in conjunction with Nω-Nitro-L-arginine methyl ester (L-NAME) administration. TQ was administered at a dosage of 50 mg/kg daily, while exercise regimens consisted of training at 60% of maximal velocity (V-max) five days per week for 12 weeks. In vitro HFpEF models were established using H9c2 cardiomyoblast cells treated with L-NAME. Analytical methods included immunofluorescence, co-immunoprecipitation, and TUNEL assays to assess cellular and molecular changes. The combination of TQ and aerobic exercise significantly attenuated myocardial fibrosis, apoptosis, and oxidative stress more effectively than either intervention alone. Mechanistically, the combined treatment downregulated the interaction between Apaf1 and Cycs, thereby inhibiting cardiomyocyte apoptosis. These results suggest that the adjunctive use of TQ and aerobic exercise may confer therapeutic benefits in HFpEF by alleviating cardiac damage through modulation of the Apaf1/Cycs apoptotic pathway.