Cell-Specific Dysregulation of MicroRNA Expression in Obese White Adipose Tissue

Context: Obesity is characterized by the excessive accumulation of dysfunctional white adipose tissue (WAT), leading to a strong perturbation of metabolic regulations. However, the molecular events underlying this process are not fully understood. Objective: MicroRNAs (miRNAs) are small noncoding RNAs acting as posttranscriptional regulators of gene expression in multiple tissues and organs. However, their expression and roles in WAT cell subtypes, which include not only adipocytes but also immune, endothelial, and mesenchymal stem cells as well as preadipocytes, have not been characterized. Design/Results: By applying differential miRNome analysis, we demonstrate that the expression of several miRNAs is dysregulated in epididymal WAT from ob/ob and high-fat diet-fed mice. Adipose tissue-specific down-regulation of miR-200a and miR-200b and the up-regulation of miR-342–3p, miR-335–5p, and miR-335–3p were observed. Importantly, a similarly altered expression of miR-200a and miR-200b was observed in obese d...