title: Glucose-independent persistence of PAI-1 gene expression and H3K4 tri-methylation in type 1 diabetic mouse endothelium: implication in metabolic memory.
abstract: Clinical trials with type 1 and type 2 diabetes have identified a phenomenon known as "metabolic memory" in which previous periods of hyperglycemia result in the long-lasting deleterious impact on cardiovascular events. Emerging evidence shows that transient hyperglycemic exposure of human endothelial cells induces histone 3 lysine 4 mono-methylation (H3K4me1) on the promoter and persistent mRNA expression of RelA and IL-8 genes, suggesting that epigenetic histone modification and chromatin structure remodeling is a key event underlying metabolic memory. This burgeoning hypothesis, however, critically remains to be tested for relevance in the disease process of diabetes in vivo, and for broader applicability to an array of genes involved in endothelial dysfunction. To address this, we used type 1 diabetes mouse model induced by streptozocin to be hyperglycemic for 8 weeks, and isolated endothelial cells that were used either freshly after isolation or after 2 to 3-week cell culture in normoglycemic conditions. mRNA expression profiling in diabetic mouse endothelial cells revealed significant and persistent up-regulation of Serpine1 encoding PAI-1, the hypo-fibrinolytic mediator leading to thrombotic diseases in diabetes, along with Rock2, Fn1 and Ccl2, whereas only Serpine 1 was persistently elevated in high glucose-treated mouse endothelial cells. Chromosome immunoprecipitation assay in type 1 diabetic mouse endothelial cells showed predominant enrichment of H3K4 tri-methylation on Serpine1 promoter, suggesting a unique epigenetic regulation in diabetic mice as opposed to high glucose-treated human ECs. Our study demonstrates the importance of combining in vivo models of diabetes with high glucose-treated cell culture to better assess the epigenetic mechanisms relevant to disease.
authors: Department of Pediatrics and Developmental Biology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Tokyo 113-8510, Japan.
authors: Fumihiko
authors: F
authors: Takizawa
authors: Shuki
authors: S
authors: Mizutani
authors: Yoshihiro
authors: Y
authors: Ogawa
authors: Naoki
authors: N
authors: Sawada
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D042002:Chromatin Assembly and Disassembly; D003921:Diabetes Mellitus, Experimental / Q000235:genetics / Q000378:metabolism; D003922:Diabetes Mellitus, Type 1 / Q000235:genetics* / Q000378:metabolism*; D042783:Endothelial Cells / Q000187:drug effects / Q000378:metabolism; D044127:Epigenesis, Genetic; D015870:Gene Expression / Q000187:drug effects; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D006657:Histones / Q000737:chemistry / Q000378:metabolism*; D006801:Humans; D008297:Male; D008745:Methylation; D051379:Mice; D008810:Mice, Inbred C57BL; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D058258:Serpin E2 / Q000235:genetics*
chemical_list: D006657:Histones; D012333:RNA, Messenger; D058258:Serpin E2; C511869:Serpine2 protein, mouse; D005947:Glucose