A novel system-level approach using RNA-sequencing data identifies miR-30-5p and miR-142a-5p as key regulators of apoptosis in myocardial infarction
SCIENTIFIC REPORTS
Authors: Kim, Jin Ock; Park, Jei Hyoung; Kim, Taeyong; Hong, Seong Eui; Lee, Ji Young; Nho, Kyoung Jin; Cho, Chunghee; Kim, Yong Sook; Kang, Wan Seok; Ahn, Youngkeun; Kim, Do Han
Abstract
This study identified microRNAs involved in myocardial infarction (MI) through a novel system-level approach using RNA sequencing data in an MI mouse model. This approach involved the extraction of DEGs and DEmiRs from RNA-seq data in sham and MI samples and the subsequent selection of two miRNAs: miR-30-5p (family) and miR-142a-5p, which were downregulated and upregulated in MI, respectively. Gene Set Enrichment Analysis (GSEA) using the predicted targets of the two miRNAs suggested that apoptosis is an essential gene ontology (GO)-associated term. In vitro functional assays using neonatal rat ventricular myocytes (NRVMs) demonstrated that miR-30-5p is anti-apoptotic and miR-142a-5p is pro-apoptotic. Luciferase assays showed that the apoptotic genes, Picalm and Skil, and the anti-apoptotic genes, Ghr and Kitl, are direct targets of miR-30-5p and miR-142a-5p, respectively. siRNA studies verified the results of the luciferase assays for target validation. The results of the system-level high throughput approach identified a pair of functionally antagonistic miRNAs and their targets in MI. This study provides an in-depth analysis of the role of miRNAs in the pathogenesis of MI which could lead to the development of therapeutic tools. The system-level approach could be used to identify miRNAs involved in variety of other diseases.
The role of growth hormone receptor in beta cell function
GROWTH HORMONE & IGF RESEARCH
Authors: Wang, Shuang; Wu, Jin; Wang, Ning; Zeng, Li; Wu, Yingjie
Abstract
Growth hormone (GH) exerts numerous effects on tissues through binding to its receptor, GHR, which resides on cell membranes in many different organs and tissues. Endocrine pancreatic beta cells are the only source of insulin secretion in response to metabolic demand, thereby regulating blood glucose and maintaining metabolic homeostasis. beta cell dysfunction is the main composition of diabetes mellitus. Numerous studies have provided strong evidence that GHR signaling plays an independent role in beta cell function. In this review, we focus on the role of GHR signaling in beta cell actions and the underlying molecular mechanisms.