Project description:Vascular calcification is a hallmark of atherosclerosis and end-stage renal disease (ESRD). However, the molecular mechanism of vascular calcification is poorly understood. Diabetes mellitus is increasingly recognized as the most important cause for atherosclerosis and ESRD. Emerging evidence supports the concept that vascular calcification resembles the process of osteogenesis, in which the vascular smooth muscle cells (VSMC) undergo osteochondrogenic differentiation. Recently, we have established an in vitro calcification system with primary mouse VSMC. With the use of osteogenic stimuli, we induced trans-differentiation of primary mouse VSMC into bone-like cells. Interestingly stroptozotocin (STZ), O-GlcNAcase inhibitor and a drug that has been used to induce diabetes in mice, was able to induce calcification of VSMC and the expression of the osteogenic transcription factor Runx2, suggesting glycosylation may be involved in regulation of Runx2. We have reported an essential role of Runx2 in oxidative stress-induce VSMC calcification and have recently generated a tissue specific mouse with Runx2 ablation in smooth muscle cells. Therefore, we will use STZ and other relevant reagents in the glucose synthesis/metabolism pathways as stimuli for VSMC calcification to characterize the glycogene profiles during VSMC calcification. Results from VSMC of Runx2 knockout mice will be compared with those from control mice to determine the regulation of calcification-associated glycogenes by Runx2 in response to STZ. These studies will provide foundation for further mechanistic studies and may lead to identification of novel strategies and targets for diabetes-induced vascular calcification. To examine vascular smooth muscle cells (VSMC) under two conditions: 1) wild-type VSMC differentiated into bone-like cells with osteogenic media, 2) wild-type VSMC treated with STZ and osteogenic media
Project description:Vascular calcification is a complex process and has been associated with aging, diabetes, chronic kidney disease (CKD). Although there have been several studies studying the role of miRNAs (miRs) in bone osteogenesis, little is known about the role of miRs in vascular calcification and their role in the pathogenesis of vascular abnormalities. Matrix vesicles (MV) are known to play an important role in initiating vascular smooth muscle cell (VSMC) calcification. In the present study, we performed miRNA microarray analysis to identify the dysregulated miRs between MV and VSMC derived from CKD rats to understand the role of post-transcriptional regulatory networks governed by these miRNAs in vascular calcification and to uncover the differential miRNA content of MV. The percentage of miRNA to total RNA was increased in MV compared to VSMC. Comparison of expression profiles of miRNA by microarray demonstrated 33 miRs to be differentially expressed with the majority (~ 57%) of them down-regulated. Target genes controlled by differentially expressed miRNAs were identified utilizing two different complementary computational approaches Miranda and Targetscan to understand the functions and pathways that may be affected due to the production of MV from calcifying VSMC thereby contributing to the regulation of genes by miRs. We found several processes including vascular smooth muscle contraction, response to hypoxia and regulation of muscle cell differentiation to be enriched. Signaling pathways identified included MAP-kinase and wnt signaling that have previously been shown to be important in vascular calcification. In conclusion, our results demonstrate that miRs are concentrated in MV from calcifying VSMC, and that important functions and pathways are affected by the miRs dysregulation between calcifying VSMC and the MV they produce. This suggests that miRs may play a very important regulatory role in vascular calcification in CKD by controlling an extensive network of post-transcriptional targets. Compare miRNA from matrix vesicles to miRNA from vascular smooth muscle cells that gave rise to the matrix vesicles from 3 sets of MV and VSMC derived from 3 normal and 3 CKD rats
Project description:The heterogeneity of endothelial cells (ECs), lining blood vessels, across tissues remains incompletely inventoried. We constructed an atlas of >32,000 single-EC transcriptomic data from 11 tissues of the model organism Mus musculus. We propose a new classification of EC phenotypes based on transcriptome signatures and inferred putative biological features. We identified top-ranking markers for ECs from each tissue. ECs from different vascular beds (arteries, capillaries, veins, lymphatics) resembled each other across tissues, but only arterial, venous and lymphatic (not capillary) ECs shared markers, illustrating a greater heterogeneity of capillary ECs. We identified high-endothelial-venule and lacteal-like ECs in the intestines, and angiogenic ECs in healthy tissues. Metabolic transcriptomes of ECs differed amongst spleen, lung, liver, brain and testis, while being similar for kidney, heart, muscle and intestines. Within tissues, metabolic gene expression was heterogeneous amongst ECs from different vascular beds, altogether highlighting large EC heterogeneity.
Project description:Vascular calcification is a hallmark of atherosclerosis and end-stage renal disease (ESRD). However, the molecular mechanism of vascular calcification is poorly understood. Diabetes mellitus is increasingly recognized as the most important cause for atherosclerosis and ESRD. Emerging evidence supports the concept that vascular calcification resembles the process of osteogenesis, in which the vascular smooth muscle cells (VSMC) undergo osteochondrogenic differentiation. Recently, we have established an in vitro calcification system with primary mouse VSMC. With the use of osteogenic stimuli, we induced trans-differentiation of primary mouse VSMC into bone-like cells. Interestingly stroptozotocin (STZ), O-GlcNAcase inhibitor and a drug that has been used to induce diabetes in mice, was able to induce calcification of VSMC and the expression of the osteogenic transcription factor Runx2, suggesting glycosylation may be involved in regulation of Runx2. We have reported an essential role of Runx2 in oxidative stress-induce VSMC calcification and have recently generated a tissue specific mouse with Runx2 ablation in smooth muscle cells.
Project description:Vascular smooth muscle cells (VSMCs) show pronounced heterogeneity across and within vascular beds, with direct implications for their function in injury response and atherosclerosis. Here we combine single-cell transcriptomics with lineage tracing to examine VSMC heterogeneity in healthy mouse vessels. The transcriptional profiles of single VSMCs consistently reflect their region-specific developmental history and show heterogeneous expression of vascular disease-associated genes involved in inflammation, adhesion and migration. We detect a rare population of VSMC-lineage cells that express the multipotent progenitor marker Sca1, progressively downregulate contractile VSMC genes and upregulate genes associated with VSMC response to inflammation and growth factors. We find that Sca1 upregulation is a hallmark of VSMCs undergoing phenotypic switching in vitro and in vivo, and reveal an equivalent population of Sca1-positive VSMC-lineage cells in atherosclerotic plaques. Together, our analyses identify disease-relevant transcriptional signatures in VSMC-lineage cells in healthy blood vessels, with implications for disease susceptibility, diagnosis and prevention.
Project description:Vascular calcification is a complex process and has been associated with aging, diabetes, chronic kidney disease (CKD). Although there have been several studies studying the role of miRNAs (miRs) in bone osteogenesis, little is known about the role of miRs in vascular calcification and their role in the pathogenesis of vascular abnormalities. Matrix vesicles (MV) are known to play an important role in initiating vascular smooth muscle cell (VSMC) calcification. In the present study, we performed miRNA microarray analysis to identify the dysregulated miRs between MV and VSMC derived from CKD rats to understand the role of post-transcriptional regulatory networks governed by these miRNAs in vascular calcification and to uncover the differential miRNA content of MV. The percentage of miRNA to total RNA was increased in MV compared to VSMC. Comparison of expression profiles of miRNA by microarray demonstrated 33 miRs to be differentially expressed with the majority (~ 57%) of them down-regulated. Target genes controlled by differentially expressed miRNAs were identified utilizing two different complementary computational approaches Miranda and Targetscan to understand the functions and pathways that may be affected due to the production of MV from calcifying VSMC thereby contributing to the regulation of genes by miRs. We found several processes including vascular smooth muscle contraction, response to hypoxia and regulation of muscle cell differentiation to be enriched. Signaling pathways identified included MAP-kinase and wnt signaling that have previously been shown to be important in vascular calcification. In conclusion, our results demonstrate that miRs are concentrated in MV from calcifying VSMC, and that important functions and pathways are affected by the miRs dysregulation between calcifying VSMC and the MV they produce. This suggests that miRs may play a very important regulatory role in vascular calcification in CKD by controlling an extensive network of post-transcriptional targets.
Project description:Vascular calcification is the ectopic deposition of calcium hydroxyapatite minerals in arterial wall. However, the underlying molecular mechanisms regulating vascular calcification remain incompletely understood. In this study, we applied RNA sequencing to explore the mechanism of vascular calcificaiton in both medial and atherosclerotic vascular calcification models.
Project description:Hyperglycemia accelerates calcification of atherosclerotic plaques in diabetic patients, and the prolonged accumulation of advanced glycation end products (AGEs) induced by hyperglycemia may be closely related to the pathogenesis of aortic calcification. However, the mechanisms underlying this association remain unclear. In the current study, we investigated the role of vascular smooth muscle cell nuclear factor 90/110 (NF90/110) in mediating AGEs accumulation and accelerating diabetic atherosclerotic calcification. Using vascular smooth muscle cells (VSMCs), human samples, and mouse models, we found that hyperglycemia-mediated AGEs markedly increased VSMC NF90/110 activation both in human and mouse atherosclerotic calcified tissues with diabetes. Silencing of NF90/110 in vitro and genetic deletion of VSMC NF90/110 in mice decreased obviously AGEs-induced arteriosclerotic calcification. Mechanistically, AGEs increased the activity of NF90, which then enhanced ubiquitination and degradation of AGE receptor 1 (AGER1) by stabilizing the mRNA of E3 ubiquitin ligase, F-box, and WD repeat domain 7 (FBXW7), thus causing the accumulation of more AGEs. Furthermore, AGEs accumulation accelerated diabetic atherosclerotic calcification by inducing VSMC phenotypic changes to osteoblast-like cells, apoptosis, and matrix vesicle release. Collectively, our study demonstrated the effects of VSMC NF90 in mediating the metabolic imbalance of AGEs to accelerate diabetic arteriosclerotic calcification. These novel findings elucidate a pivotal mechanism underlying AGE-induced diabetic atherosclerotic calcification and provide a framework for potential interventions against diabetic vascular complications.
Project description:Arterial media calcification caused by diabetes is an important cause of vascular calcification. Dipeptidyl peptidase-4 (DPP4) is associated with diabetic arterial media calcification. At the same time, long non-coding RNA(lncRNA) is closely related to the evolution of a variety of cardiovascular diseases, but the involvement of lncRNA in vascular calcification induced by DPP4 has not been reported in details. In this study, we established a model of human aortic smooth muscle cells (HASMCs) calcification induced by DPP4. There was a significant difference in the expression of lncRNAs and mRNAs between normal and calcified vascular smooth muscle cells detected by gene chip technology. Based on the results of microarray detection, we found that lncRNA may be involved in vascular calcification induced by DPP4 through regulating target genes.