Abstract

Myocardial ischemia–reperfusion injury (MIRI) remains a major clinical challenge due to limited therapeutic options and the risk of complications such as hemorrhage. Dihydromyricetin (DMY), a flavonoid derived from Vine tea, has shown cardioprotective effects, but its mechanism of action in MIRI is not fully understood. This study aimed to investigate the therapeutic effects of DMY on MIRI and elucidate the underlying molecular mechanisms. A rat model of MIRI was established by left anterior descending coronary artery ligation. Rats received DMY or the positive control diltiazem (DIL) for 7 days post-injury. Cardiac damage was assessed by measuring cardiac troponin levels and histopathological analysis. The expression of chemokine-like factor 1 (CKLF1) and its downstream signaling pathways was examined using molecular and biochemical approaches. The interaction between DMY and CKLF1 was further validated using a CKLF1 agonist (C27) and CKLF1-knockout rats. CKLF1 expression was significantly upregulated in MIRI, correlating with inflammatory infiltration, tissue disorganization, and elevated cardiac troponin levels. Mechanistically, CKLF1 activation promoted phosphorylation of nuclear factor kappa-B (NF-κB) and subsequent assembly of the NLR family pyrin domain-containing 3 (NLRP3) inflammasome, leading to caspase-1-dependent pyroptosis. DMY treatment attenuated these effects by downregulating CKLF1 expression and disrupting its interaction with C-C chemokine receptor type 5 (CCR5) and NLRP3, thereby suppressing pyroptosis. Notably, activation of CKLF1 signaling by its agonist C27 reversed the protective effects of DMY. Moreover, while CKLF1 knockout modestly reduced pyroptosis-related protein expression, the anti-pyroptotic effect of DMY was abolished in knockout rats, indicating its dependence on CKLF1. These findings demonstrate that DMY alleviates MIRI by targeting the CKLF1/NF-κB/NLRP3 axis, thereby inhibiting pyroptosis and preserving cardiomyocyte integrity.