CEBPD REGULATES OXIDATIVE STRESS AND INFLAMMATORY RESPONSES IN HYPERTENSIVE CARDIAC REMODELING

Abstract

ABSTRACT Hypertension seems to inevitably cause cardiac remodeling, increasing the mortality of patients. This study aimed to explore the molecular mechanism of CCAAT/enhancer-binding protein delta (CEBPD)–mediated oxidative stress and inflammation in hypertensive cardiac remodeling. The hypertensive murine model was established through angiotensin-II injection, and hypertensive mice underwent overexpressed CEBPD vector injection, cardiac function evaluation, and observation of histological changes. The cell model was established by angiotensin-II treatment and transfected with overexpressed CEBPD vector. Cell viability and surface area and oxidative stress (reactive oxygen species/superoxide dismutase/lactate dehydrogenase/malondialdehyde) were assessed, and inflammatory factors (TNF-α/IL-1β/IL-6/IL-10) were determined both in vivo and in vitro. The levels of CEBPD, miR-96-5p, inositol 1,4,5-trisphosphate receptor 1 (IP3R), natriuretic peptide B, and natriuretic peptide A, collagen I, and collagen III in tissues and cells were determined. The binding relationships of CEBPD/miR-96-5p/IP3R 3′ untranslated region were validated. CEBPD was reduced in cardiac tissue of hypertensive mice, and CEBPD upregulation improved cardiac function and attenuated fibrosis and hypertrophy, along with reductions of reactive oxygen species/lactate dehydrogenase/malondialdehyde/TNF-α/IL-1β/IL-6 and increases in superoxide dismutase/IL-10. CEBPD enriched on the miR-96-5p promoter to promote miR-96-5p expression, whereas CEBPD and miR-96-5p negatively regulated IP3R. miR-96-5p silencing/IP3R overexpression reversed the alleviative role of CEBPD overexpression in hypertensive mice. In summary, CEBPD promoted miR-96-5p to negatively regulate IP3R expression to inhibit oxidative stress and inflammation, thereby alleviating hypertensive cardiac remodeling.