Hyperglycemia Induces Myocardial Dysfunction via Epigenetic Regulation of JunD. Issue 10 (23rd October 2020)

• Record Type: Journal Article
• Authors: Hussain, Shafaat; Khan, Abdul Waheed; Akhmedov, Alexander; Suades, Rosa; Costantino, Sarah; Paneni, Francesco; Caidahl, Kenneth; Mohammed, Shafeeq A.; Hage, Camilla; Gkolfos, Christos; Björck, Hanna; Pernow, John; Lund, Lars H.; Lüscher, Thomas F.; Cosentino, Francesco
• Is Part Of: Circulation research. Volume 127:Issue 10(2020)
• Publication Date: 2020-10-23
• Subjects: diabetes mellitus -- heart failure -- microRNA -- reactive oxygen species -- transcription factors; Cardiovascular system -- Periodicals; Blood -- Circulation -- Periodicals; Blood Circulation; Cardiovascular System; Vascular Diseases; Sang -- Circulation -- Périodiques; Appareil cardiovasculaire -- Périodiques; 612.1
• DOI: 10.1161/CIRCRESAHA.120.317132
• Languages: English
• ISSNs: 0009-7330

Abstract

Abstract : Rationale: Hyperglycemia -induced reactive oxygen species are key mediators of cardiac dysfunction. JunD (Jund proto-oncogene subunit), a member of the AP-1 (activator protein-1) family of transcription factors, is emerging as a major gatekeeper against oxidative stress. However, its contribution to redox state and inflammation in the diabetic heart remains to be elucidated. Objective: The present study investigates the role of JunD in hyperglycemia-induced and reactive oxygen species–driven myocardial dysfunction. Methods and Results: JunD mRNA and protein expression were reduced in the myocardium of mice with streptozotocin-induced diabetes mellitus as compared to controls. JunD downregulation was associated with oxidative stress and left ventricular dysfunction assessed by electron spin resonance spectroscopy as well as conventional and 2-dimensional speckle-tracking echocardiography. Furthermore, myocardial expression of free radical scavenger superoxide dismutase 1 and aldehyde dehydrogenase 2 was reduced, whereas the NOX2 (NADPH [nicotinamide adenine dinucleotide phosphatase] oxidase subunit 2) and NOX4 (NADPH [nicotinamide adenine dinucleotide phosphatase] oxidase subunit 4) were upregulated. The redox changes were associated with increased NF-κB (nuclear factor kappa B) binding activity and expression of inflammatory mediators. Interestingly, mice with cardiac-specific overexpression of JunD via the α MHC (α- myosin heavy chain) promoter (α MHC JunD tg ) were protected against hyperglycemia-induced cardiac dysfunction. We also showed that JunD was epigenetically regulated by promoter hypermethylation, post-translational modification of histone marks, and translational repression by miRNA (microRNA)-673/menin. Reduced JunD mRNA and protein expression were confirmed in left ventricular specimens obtained from patients with type 2 diabetes mellitus as compared to nondiabetic subjects. Conclusions: Here, we show that a complex epigenetic machinery involving DNA methylation, histone modifications, and microRNAs mediates hyperglycemia-induced JunD downregulation and myocardial dysfunction in experimental and human diabetes mellitus. Our results pave the way for tissue-specific therapeutic modulation of JunD to prevent diabetic cardiomyopathy. Abstract : Supplemental Digital Content is available in the text.