Zinc Finger Protein ZBTB20 protects against cardiac remodelling post-myocardial infarction via ROS-TNFα/ASK1/JNK pathway regulation.

This study aims to determine the efficacy of Zinc finger protein ZBTB20 in treatment of post-infarction cardiac remodelling. For this purpose, left anterior descending (LAD) ligation was operated on mice to induce myocardial infarction (MI) with sham control group as contrast and adeno-associated virus (AAV9) system was used to deliver ZBTB20 to mouse heart by myocardial injection with vehicle-injected control group as contrast two weeks before MI surgery. Then four weeks after MI, vehicle-treated mice with left ventricular (LV) remodelling underwent deterioration of cardiac function, with symptoms of hypertrophy, interstitial fibrosis, inflammation and apoptosis. The vehicle-injected mice also showed increase of infarct size and decrease of survival rate. Meanwhile, the ZBTB20-overexpressed mice displayed improvement after MI. Moreover, the anti-apoptosis effect of ZBTB20 was further confirmed in H9c2 cells subjected to hypoxia in vitro. Further study suggested that ZBTB20 exerts cardioprotection by inhibiting tumour necrosis factor α/apoptosis signal-regulating kinase 1 (ASK1)/c-Jun N-terminal kinase 1/2 (JNK1/2) signalling, which was confirmed by shRNA-JNK adenoviruses transfection or a JNK activator in vitro as well as ASK1 overexpression in vivo. In summary, our data suggest that ZBTB20 could alleviate cardiac remodelling post-MI. Thus, administration of ZBTB20 can be considered as a promising treatment strategy for heart failure post-MI. Significance Statement: ZBTB20 could alleviate cardiac remodelling post-MI via inhibition of ASK1/JNK1/2 signalling.

NLRP3 deficiency accelerates pressure overload-induced cardiac remodeling via increased TLR4 expression.

NLRP3, a member of the nucleotide-binding oligomerization domain (NOD)-like receptor family, is involved in cardiac inflammation. However, the functional role of NLRP3 in cardiac remodeling is not clear. To investigate the roles of NLRP3 in pressure overload-induced cardiac remodeling, NLRP3 knockout and wild-type mice were subjected to aortic banding to induce cardiac remodeling. The data showed that NLRP3 expression was downregulated in the remodeling process. NLRP3 deficiency accelerated cardiac hypertrophy, fibrosis, and inflammation responses with deteriorating cardiac dysfunction in the pressure overload-induced cardiac remodeling mouse model. Neonatal rat cardiomyocytes were isolated and stimulated with phenylephrine (PE). We identified NLRP3 as a negative regulator of cardiomyocyte remodeling in PE-stimulated cardiomyocyte remodeling using adenovirus-NLRP3 and NLRP3 siRNA. Mechanistically, we found that the expression of Toll-like receptor (TLR) 4 was upregulated in NLRP3-deficient mouse hearts and PE-stimulated cardiomyocytes. NLRP3 knockout mice subjected to a TLR4 inhibitor revealed a relieved cardiac remodeling response with improved cardiac dysfunction. Our data suggested that NLRP3 could be a therapeutic target for cardiac remodeling and heart failure. KEY MESSAGES: NLRP3 expression was downregulated in the remodeling process. NLRP3 deficiency accelerated pressure overload-induced cardiac remodeling. NLRP3 acted as a negative regulator of cardiomyocyte remodeling via downregulating TLR4.