Subcellular microRNAs in diabetic cardiomyopathy

Role of mitochondrial DNA in diabetes Mellitus Type I and Type II

Morbidity and mortality from diabetes mellitus and associated illnesses is a major problem across the globe. Anti-diabetic medicines must be improved despite existing breakthroughs in treatment approaches. Diabetes has been linked to mitochondrial dysfunction. As a result, particular mitochondrial diabetes kinds like MIDD (maternally inherited diabetes & deafness) and DAD (diabetic autonomic dysfunction) have been identified and studied (diabetes and Deafness). Some mutations as in mitochondrial DNA (mtDNA), that encodes for a significant portion of mitochondrial proteins as well as mitochondrial tRNA essential for mitochondrial protein biosynthesis, are responsible for hereditary mitochondrial diseases. Tissue-specificity and heteroplasmy have a role in the harmful phenotype of mtDNA mutations, making it difficult to generalise findings from one study to another. There are a huge increase in the number for mtDNA mutations related with human illnesses that have been identified using current sequencing technologies. In this study, we make a list on mtDNA mutations linked with diseases and diabetic illnesses and explore the methods by which they contribute to the pathology's emergence.

Biological Functions and Clinical Prospects of Extracellular Non-Coding RNAs in Diabetic Cardiomyopathy: an Updated Review

Diabetic cardiomyopathy (DCM) is one of the major causes of heart failure in diabetic patients. However, the pathogenesis of diabetic cardiomyopathy has not been fully elucidated. Diagnosis and therapeutic strategy of DCM is still challenging. Various non-coding RNAs (ncRNA) are implicated in the onset and progression of DCM. Interestingly, ncRNAs not only are regulators intracellularly, but also can exist and function in extracellular space. Recent evidences have demonstrated that extracellular ncRNAs play emerging roles in both intracardiac and inter-organ communication during the pathogenesis of DCM; thus, extracellular ncRNAs are attractive diagnostic biomarkers and potential therapeutic targets for DCM. This article will review the current knowledge of the roles of extracellular ncRNAs in DCM, especially focusing on their physio-pathological properties and perspectives of potential clinical translation for biomarkers and therapies. Recent evidences have demonstrated that extracellular ncRNA play emerging roles in both intracardiac and inter-organ communication involved in the pathogenesis of diabetic cardiomyopathy (DCM), thus shown as attractive diagnostic biomarkers and potential therapeutics for DCM. In the current review, we first summarize the progress regarding the paracrine role of extracellular ncRNA in DCM. miRNAs and circRNAs have been shown to mediate the communication among cardiomyocytes, endothelial cells, and vascular smooth muscle cells in the diabetic heart. Subsequently, we systematically describe that extracellular ncRNAs contribute to the crosstalk between the heart and other organs in the context of diabetes. Researches have indicated that miRNAs acted as hepatokines and adipokines to mediates the injure effect of distal organs on hearts. As for clinical application, extracellular ncRNAs are promising biomarker and have therapeutic potential. (Created with BioRender.com).

Susceptibility Modules and Genes in Hypertrophic Cardiomyopathy by WGCNA and ceRNA Network Analysis

Background: We attempted to identify a regulatory competing endogenous RNA (ceRNA) network and a hub gene of Hypertrophic Cardiomyopathy (HCM). Methods: Microarray datasets of HCM tissue were obtained from NCBI Gene Expression Omnibus (GEO) database. The R package "limma" was used to identify differentially expressed genes. Online search databases were utilized to match the relation among differentially expressed long non-coding RNAs (lncRNAs), microRNAs (miRNAs) and mRNAs. Weighted correlation network analysis (WGCNA) was used to identify the correlations between key modules and HCM. STRING database was applied to construct PPI networks. Gene Set Enrichment Analysis (GSEA) was used to perform functional annotations and verified the hub genes. Results: A total of 269 DE-lncRNAs, 63 DE-miRNAs and 879 DE-mRNAs were identified in myocardial tissues from microarray datasets GSE130036, GSE36946 and GSE36961, respectively. According to online databases, we found 1 upregulated miRNA hsa-miR-184 that was targeted by 2 downregulated lncRNAs (SNHG9, AC010980.2), potentially targeted 2 downregulated mRNAs (LRRC8A, SLC7A5). 3 downregulated miRNAs (hsa-miR-17-5p, hsa-miR-876-3p, hsa-miR-139-5p) that were targeted by 9 upregulated lncRNAs, potentially targeted 21 upregulated mRNAs. Black and blue modules significantly related to HCM were identified by WGCNA. Hub gene IGFBP5 regulated by hsa-miR-17-5p, AC007389.5, AC104667.1, and AC002511.2 was identified. GSEA indicated that IGFBP5 might involve in the synthesis of myosin complex, participate in kinesin binding, motor activity and function via the regulation of actin cytoskeleton. Conclusion: The results provide a potential molecular regulatory mechanism for the diagnosis and treatment of HCM. IGFBP5 might play an important role in the progression of HCM.

Hyperglycemic memory in diabetic cardiomyopathy

Cardiovascular diseases account for approximately 80% of deaths among individuals with diabetes mellitus, with diabetic cardiomyopathy as the major diabetic cardiovascular complication. Hyperglycemia is a symptom that abnormally activates multiple downstream pathways and contributes to cardiac hypertrophy, fibrosis, apoptosis, and other pathophysiological changes. Although glycemic control has long been at the center of diabetes therapy, multicenter randomized clinical studies have revealed that intensive glycemic control fails to reduce heart failure-associated hospitalization and mortality in patients with diabetes. This finding indicates that hyperglycemic stress persists in the cardiovascular system of patients with diabetes even if blood glucose level is tightly controlled to the normal level. This process is now referred to as hyperglycemic memory (HGM) phenomenon. We briefly reviewed herein the current advances that have been achieved in research on the underlying mechanisms of HGM in diabetic cardiomyopathy.

The Role of Mitochondrial Mutations and Chronic Inflammation in Diabetes

Diabetes mellitus and related disorders significantly contribute to morbidity and mortality worldwide. Despite the advances in the current therapeutic methods, further development of anti-diabetic therapies is necessary. Mitochondrial dysfunction is known to be implicated in diabetes development. Moreover, specific types of mitochondrial diabetes have been discovered, such as MIDD (maternally inherited diabetes and deafness) and DAD (diabetes and Deafness). Hereditary mitochondrial disorders are caused by certain mutations in the mitochondrial DNA (mtDNA), which encodes for a substantial part of mitochondrial proteins and mitochondrial tRNA necessary for mitochondrial protein synthesis. Study of mtDNA mutations is challenging because the pathogenic phenotype associated with such mutations depends on the level of its heteroplasmy (proportion of mtDNA copies carrying the mutation) and can be tissue-specific. Nevertheless, modern sequencing methods have allowed describing and characterizing a number of mtDNA mutations associated with human disorders, and the list is constantly growing. In this review, we provide a list of mtDNA mutations associated with diabetes and related disorders and discuss the mechanisms of their involvement in the pathology development.