Single cell analysis reveals the heterogeneity of fibroblasts in the diabetic heart
Ontology highlight
ABSTRACT: Diabetes mellitus is one of the most chronic diseases, of which diabetic cardiomyopathy is the major cause of morbidity and involves in multiple processes such as inflammation, oxidative stress, fibrosis, extracellular collagen deposition, apoptosis, mitochondria dysfunction. However, the exact mechanisms of fibroblasts concerning type Ⅰ diabetes remain unclear. To further understand the functional roles of fibroblasts of STZ-induced diabetic mice, we lead the single cell RNA sequence. Cells were comprised of endothelial, fibroblast, cardiomyocyte, smooth muscle cells, macrophage and other type cells. Single cell sequence illustrates novel fibroblast sub-clusters and highlight the role of Lox. Real-time quantitative PCR, western blotting, immunofluorescence was used to verify the sequence data. We validate the dysfunctions of diabetic cardiomyopathy by echocardiogram. Our study supports novel insights into the pathogenesis of diabetic cardiomyopathy.
Project description:Diabetic cardiomyopathy (DCM) is an important complication of chronic diabetes mellitus (DM). However, its pathogenesis and pathologic process have not been fully elucidated. This study was aimed to investigate the role of ferroptosis in the pathogenesis of DCM and clarify the effect of HMOX1 on DCM by targeting ferroptosis. DCM mouse model was constructed by high fat diet (HFD) feeding and streptozotocin (STZ). injection.
Project description:The targeted muscle insulin receptor knockout (MIRKO) model was used, in which there is a complete absence of the insulin-receptor signaling in skeletal muscle but normal insulin and glucose levels. By comparing skeletal muscle gene-expression profiles from MIRKO mice and their controls (lox/lox) under three different metabolic conditions (namely, in the basal state, after streptozotocin (STZ)-induced diabetes, and after STZ-induced diabetes rendered euglycemic with insulin treatment), we can address the following three important questions. (i) What is the direct effect of the loss of insulin signaling on gene expression in skeletal muscle? (ii) What is the contribution of the metabolic and other changes that accompany diabetes to induce indirect changes in gene expression? (iii) How are these pathways regulated and implicated in the pathophysiology of diabetes?
Project description:Our study provides the first direct evidence supporting a fibroblast-mediated mechanism of dysfunction and adverse remodeling in the diabetic heart, highlighting the importance of interstitial cells in the pathogenesis of diabetic cardiomyopathy. Diabetes-associated activation of the TGF-b/Smad3 cascade may promote dysfunction not only by accentuating ECM deposition and crosslinking, but also by modulating cardiomyocyte phenotype and function. Thus, the TGF-b system may be a promising therapeutic target in patients with diabetes-associated heart failure.
Project description:Our study provides the first direct evidence supporting a fibroblast-mediated mechanism of dysfunction and adverse remodeling in the diabetic heart, highlighting the importance of interstitial cells in the pathogenesis of diabetic cardiomyopathy. Diabetes-associated activation of the TGF-b/Smad3 cascade may promote dysfunction not only by accentuating ECM deposition and crosslinking, but also by modulating cardiomyocyte phenotype and function. Thus, the TGF-b system may be a promising therapeutic target in patients with diabetes-associated heart failure.
Project description:Our study provides the first direct evidence supporting a fibroblast-mediated mechanism of dysfunction and adverse remodeling in the diabetic heart, highlighting the importance of interstitial cells in the pathogenesis of diabetic cardiomyopathy. Diabetes-associated activation of the TGF-b/Smad3 cascade may promote dysfunction not only by accentuating ECM deposition and crosslinking, but also by modulating cardiomyocyte phenotype and function. Thus, the TGF-b system may be a promising therapeutic target in patients with diabetes-associated heart failure.
Project description:to gain a better understanding on the genomic mechanisms involved in defective healing in diabetes, we characterized here the gene expression profile and gene-gene interaction network of cultured fibroblasts derived from chronic diabetic leg ulcers comparatively to fibroblast obtained from control donors. Comparative transcriptomic analysis of cultured fibroblasts derived from six diabetic leg ulcers and five control fibroblasts using DNA microarrays and bioinformatics tools for studying gene-gene interaction networks.
Project description:The main cause of morbidity and mortality in diabetes mellitus (DM) are cardiovascular complications. Diabetic cardiomyopathy (DCM) remains incompletely understood. Animal models have been crucial in exploring DCM pathophysiology while identifying potential therapeutic targets. Streptozotocin (STZ) has been widely used to produce experimental models of both type 1 and type 2 DM (T1DM and T2DM). Here we compared these two models for their effects on cardiac structure, function, and transcriptome. Different doses of STZ and different diet chows were used to generate T1DM and T2DM in C57BL/6J mice. Normal euglycemic and non-obese sex and age-matched mice served as controls (CTRL). Immunohistochemistry, RT-PCR, and RNA-Seq were employed to compare hearts from the three animal groups. STZ-induced T1DM and T2DM differently affect left ventricular function and myocardial performance. T1DM displays an exaggerated apoptotic cardiomyocyte (CM) death and reactive hypertrophy and fibrosis along with increased cardiac oxidative stress, CM DNA damage and senescence when compared to T2DM mice. T1DM and T2DM differently affect whole cardiac transcriptome. In conclusion, STZ-induced T1DM and T2DM mouse models show significant differences in cardiac remodeling, function and whole transcriptome. These differences could be of key relevance when choosing an animal model to study specific features of DCM.
Project description:Cardiomyopathy in type 1 diabetic patients is characterized by early onset diastolic and late onset systolic dysfunction. The mechanism underlying development of diastolic and systolic dysfunction in diabetes remains unknown. We used microarrays to detail the ventricle gene expression changes that underly development of diabetic cardiomyopathy. We identified distinct classes of up-regulated genes during this process. Experiment Overall Design: 150g male Wistar rats (Harlan) we injected with 65 mg/kg streptozotocin to induce Type 1 diabetes. Four replicates of Control and Diabetic rat ventricles were removed and frozen at Three time points for total RNA isolation and hybridization on the Affymetrix RG-U34A microarray. The 3 day samples show a baseline for initial diabetic changes in the ventricle. The 28 day samples show changes associated with diastolic dysfunction in diabetes. The 42 day samples show changes associated with both diastolic and systolic dysfunction in type 1 diabetic rat ventricles.
Project description:Quercetin is a food component that may ameliorate the diabetic symptoms. We examined hepatic gene expression of BALB/c mice with streptozotocin (STZ)-induced diabetes to elucidate the mechanism of the protective effect of dietary quercetin on diabetes-associated liver injury. We fed STZ-induced diabetic mice with diets containing 0.1% or 0.5% quercetin for 2 weeks and compared the patterns of hepatic gene expression in these groups of mice using a DNA microarray. Diets containing 0.1% or 0.5% quercetin lowered the STZ-induced increase in blood glucose levels and improved plasma insulin levels. A cluster analysis of the hepatic gene expressions showed that 0.5% quercetin diet suppressed STZ-induced alteration of gene expression. Gene set enrichment analysis (GSEA) and quantitative RT-PCR analysis showed that the quercetin diets had their greatest suppressive effect on the STZ-induced elevation of expression of cyclin dependent kinase inhibitor p21(WAF1/Cip1) (Cdkn1a).
Project description:Patients with long-duration diabetes develop cardiovascular complications resulting in highly increased mortality and complications which affect the kidneys, eyes and peripheral nerves associated with high morbidity. Among the diabetic complications, damage in the eye, diabetic retinopathy, is the most common microvascular complication of diabetes. Diabetic retinopathy is a leading cause of vision-loss globally. It is characterized by a number of different patho-mechanisms including changes in vascular permeability, capillary degeneration, and finally at a late stage overshooting formation of new blood vessels. This expression analysis focused on the use of different experimental models for Diabetes Mellitus and its complications (for a review see 1: Al-Awar et al: Experimental Diabetes Mellitus in Different Animal Models. J Diabetes Res. 2016; doi: 10.1155/2016/9051426). By that, we wanted to uncover the relative contributions of systemic hyperinsulinaemia and/or hyperglycemia to molecular regulations. The following models have been used: As insulinopenic, hyperglycemic model reflecting Type 1 diabetes, male STZ-Wistar rats (60mg/kg BW; i.p.) were used. Wistar rats without STZ injection served as non-diabetic controls. Male obese ZDF rats (Fa/Fa) were used as type-2 diabetes model characterized by persisting hyperglycemia and transient hyperinsulinemia. Male lean ZDF rats (Fa/-) served as non-diabetic controls. Male obese ZF rats (Fa/Fa) hyperglycemia were used reflecting euglycemia and severe insulin resistance. Male lean ZF rats (Fa/-) served as controls. ZDF and ZF rats were obtained in two genotypes, obese (genotype fa/fa) and lean littermates (genotype Fa/?). All rats were housed in standard cages under a normal light-dark cycle for 16 weeks. All animals had free access to food and water. ZF and Wistar rats received a standard chow (Ssniff R/M) and ZDF rats received Purina 5008 chow. A group size of n=8 were used for all study groups. Wistar rats were rendered type-1 like hyperglycemic and hypoinsulinemic via a single injection of streptocotocin (STZ, 60mg/kg; i.p.) at 7 weeks of age. Obese ZDF rats (fa/fa) develop spontaneously a type-2 diabetes phenotype with persisting hyperglycemia and transient hyperinsulinemia (hyperglycemic, hypoinsulinemic). Obese ZF rats (fa/fa) develop insulin resistance with permanent hyperinsulinemia without concomitant hyperglycemia and no overt diabetes phenotype. Non STZ treated Wistar rats, lean ZDF littermates (Fa/?), and lean ZF littermates (Fa/?) served as controls. All groups were kept for 12 weeks on respective conditions together with appropriate age-matched controls. Unbiased gene expression analysis was performed per group using Affymetrix gene arrays.