AP2-microRNA-26a overexpression reduces visceral fat mass and blood lipids. (15th May 2021)

• Record Type: Journal Article
• Authors: Zeng, Hailuan; Sun, Weihong; Ren, Xinping; Xia, Nan; Zheng, Sheng; Xu, Haixia; Tian, Yan; Fu, Xianghui; Tian, Jingyan
• Is Part Of: Molecular and cellular endocrinology. Volume 528(2021)
• Publication Date: 2021-05-15
• Subjects: Adipose tissue -- MicroRNA-26a -- Fat expansion -- Lipids; miR-26a microRNA-26a -- eWAT epididymal white adipose tissue -- Ap2-miR-26a Mir26aloxP/loxP, Ap2-Cre+ -- WT wild-type -- HFD high-fat diet -- IPGTT intraperitoneal glucose tolerance test -- ITT insulin tolerance test -- CD chow diet -- iWAT inguinal white adipose tissue -- eWAT epididymal adipose tissue -- BAT brown adipose tissue -- H&E hematoxylin-eosin -- BW body weight -- APC adipose progenitor cell; Endocrinology -- Periodicals; Molecular biology -- Periodicals; Cytology -- Periodicals; Endocrinology -- Periodicals; Hormones -- Periodicals; Endocrinologie -- Périodiques; Cytology; Endocrinology; Molecular biology; Periodicals; 573.4
• DOI: 10.1016/j.mce.2021.111217
• Languages: English
• ISSNs: 0303-7207

Abstract

Abstract: Background: MicroRNA-26a (miR-26a) is a key player in tumor suppression and plays important roles in glucose and lipid metabolism. However, its function in adipose tissue is not well defined. Objective: The study aimed to examine the effect on fat expansion and function of miR-26a in adipose tissue. Methods: Adipose-specific miR-26a transgenic mice (Ap2-miR-26a) were firstly generated by breeding miR-26a floxed (Mir26a loxP / loxP ) mice with Ap2-Cre recombinase transgenic mice. The effects of miR-26a adipose-specific overexpression on body weight, body fat composition, fat pad weight, adipocyte size, blood lipid levels, glucose metabolism, and adipogenesis were investigated in mice on a chow diet and a high fat diet. White adipose tissue browning was evaluated by energy expenditure, adipocyte morphology and browning related genes expression levels both at room temperature and after cold exposure. Gene expression was determined by Real-Time quantitative PCR and western blotting. Results: MiR-26a was specifically overexpressed in adipose by ~4 folds. Ap2-miR-26a mice had a moderate decrease in body weight, body fat composition, epididymal white adipose (eWAT) weight and blood lipid levels, along with smaller adipocytes in eWAT. The favorable phenotype was not due to white adipose tissue browning (even after cold exposure) or adipogenesis or lipolysis. Ap2-miR-26a mice exhibited no significant metabolic phenotype under high-fat-diet feeding. Conclusion: This study suggests that adipose-specific overexpression of miR-26a could moderately reduce visceral fat pad mass and lipid levels independent of white adipose tissue browning, adipogenesis and adipose lipolysis based on the gene expression level. Highlights: Ap2-miR-26a mice had a moderate decrease in body weight, body fat composition, epididymal white adipose weight and blood lipid levels. Ap2-miR-26a and WT controls had comparable glucose metabolism on a chow diet. The favorable phenotype was not due to white adipose browning (even after cold exposure) or adipogenesis or lipolysis. Ap2-miR-26a mice exhibited no significant metabolic phenotype under high-fat-diet feeding.