Expression of microRNA-26b, an obesity-related microRNA, is regulated by free fatty acids, glucose, dexamethasone and growth hormone in human adipocytes

Abstract

Abstract. MicroRNAs (miRNAs) are short non-coding RNAs that are involved in numerous biological processes, including obesity and insulin resistance. miR-26b is an obesity-related intronic miRNA located in the intron of the carboxy-terminal domain, RNA polymerase II, polypeptide A, small phosphatase 1 gene. miR-26b is abundantly expressed in mice and mature human adipocytes, and is associated with the expression of adipokines. In the present study, the effects of energy-source materials and hormones associated with obesity, on miR-26b expression were investigated. It was demonstrated that free fatty acids (FFAs), glucose, glucocorticoids and growth hormone (GH) downregulate the expression of miR-26b in human adipocytes. The results indicate that the expression of miR-26b is affected by a variety of factors that are correlated with obesity and insulin sensitivity. Therefore, miR-26b may be an important mediator in the development of obesity-associated insulin resistance.

Extracellular NAMPT/Visfatin induces proliferation through ERK1/2 and AKT and inhibits apoptosis in breast cancer cells

“…Additionally, visfatin inhibits palmitate-induced apoptosis in pancreatic β-cells [49]. Another finding of the current study was increased survivin levels in response to visfatin which has not been previously investigated.…”

Decreased miR‐146 expression in peripheral blood mononuclear cells is correlated with ongoing islet autoimmunity in type 1 diabetes patients 1型糖尿病患者外周血单个核细胞miR‐146表达下调与胰岛持续免疫失衡相关

“…Six genes were identified as target genes of miR‐146a and miR‐146b‐5p by overlapping the differentially expressed gene list and predicted target genes using the Targetscan database, namely BCL11A , NUMB , STX3 , KLF7 ), GRID1 , and PBX2 . We examined the expression of these six genes together with tumor necrosis factor receptor‐associated factor 6 ( TRAF6 ) and interleukin‐1 receptor‐associated kinase 1 ( IRAK1 ), two known target genes of miR‐146a, using real‐time quantitative PCR. We confirmed that NUMB , STX3 , BCL11A , and TRAF6 expression was significantly upregulated in patients with newly diagnosed T1D and in those on short‐course (6 months) insulin therapy ( P < 0.05).…”

“…Whether the association between miRNA dysregulation and T1D is dependent on disease duration remains unclear. In addition, interference of hyperglycemia should be excluded because high glucose levels are associated with miRNA dysregulation …”

Regulation of MicroRNA-378 expression in mature human adipose tissue cells by adiponectin, free fatty acids and dexamethasone

“…Three durations of exposure were used i.e. 4h, 8h and 24 h. After each period of exposure, the cells were harvested and used for further investigations [10,11].…”