Adipocyte-specific SETD2 knockout impaired post-ischemic arteriogenesis and blood flow perfusion in mice by reducing FGF18 expression, leading to endothelial cell dysfunction.
SETD2-dependent epigenetic regulation in adipocytes promotes post-ischemic arteriogenesis by targeting vascular endothelial cells via FGF18 expression.
Abstract Introduction To date, several clinical trials aimed at inducing neovascularization in patients with occlusion artery disease did not achieve the expected success. Adipose tissue is the body's largest endocrine organ and plays an important role in regulating cardiovascular disease . SET-domain containing 2 (SETD2) is a histonemethyltransferase. However, little is known about the role of SETD2 mediated adipocyte dysfunction in inhibiting arteriogenesis. Objective To elucidate the role and mechanism of SETD2 mediated adipocyte dysfunction in the inhibition of arteriogenesis after ischemia. Methods 1. Single cell sequencing of adipose tissue in GEO database were analyzed to establish the correlation between adipocytes SETD2 and arteriogenesis.2. Induce hindlimb ischemia (HLI) models by ligating the femoral artery in mice . Assess blood flow signals using laser Doppler detection and visualize the lumen of arteries through colored dye vascular perfusion. Assess newborn muscle cells formation and vessel luminal size using HE, and evaluate tissue fibrosis using Masson's staining. Employ immunofluorescence staining to evaluate tissue neovascularization and cell death.3.The subcutaneous adipose tissue (SAT) and vascular matrix components (SVF) were extracted for RNA-Seq.4.Extract SVF, collect conditioned medium, and co-culture it with human umbilical vein endothelial cells (HUVEC).5.Assess changes in HUVEC functions by evaluating budding, tube formation, migration , and proliferation capabilities .6Co-culture conditioned medium with HUVEC and simultaneously add recombinant FGF18 protein (Re-FGF18) .7.Assess activity of promoter by double luciferase reporter gene assay. Results 1. Single-cell sequencing from healthy adult adipose tissue reveal that the epigenetic regulatory molecule SETD2 exhibits higher transcription levels in adipocyte subpopulations with good neovascularization.2.After HLI modeling, Ad-Setd2-CKO mice display impaired blood flow perfusion and smaller arterial vessel luminal diameter .Additionally, there is a reduction in the number of newly formed skeletal muscle cells, increased tissue fibrosis, enhanced cell apoptosis, and increased pathological capillary neovascularization .3. Following stimulation with conditioned medium from Ad-Setd2-CKO adipocytes, HUVECs exhibit reduced budding quantity, shortened bud length, significantly decreased tube length and branch crossing points.4. Multiple genes were obtained from the intersection of significantly different genes in adipose tissue and SVF in RNA-Seq. FGF18 is one of those genes.5. Re-FGF18 partially rescues the reduced functions of HUVECs.6. Luciferase experiments showed SETD2 could promote the transcriptional activity of the promoter of Fgf18. Conclusion This study is the first to identify SETD2 mediated adipocyte dysfunction that inhibits post-ischemic Arteriogenesis by targeting vascular endothelial cells through regulation of FGF18 expression.
Gong et al. (Sat,) conducted a other in Post-ischemic arterial formation. Adipocyte-specific SETD2 knockout (Ad-Setd2-CKO) vs. Control was evaluated on Blood flow perfusion and arterial vessel luminal diameter. Adipocyte-specific SETD2 knockout impaired post-ischemic arteriogenesis and blood flow perfusion in mice by reducing FGF18 expression, leading to endothelial cell dysfunction.