Long noncoding RNA ACART knockdown decreases 3T3-L1 preadipocyte proliferation and differentiation

Obesity is a main risk factor for diabetes and cardiovascular disorders and is closely linked to preadipocyte differentiation or adipogenesis. Peroxisome proliferator-activated receptor γ (PPARγ) is an indispensable transcription factor in adipogenesis. A newly identified long noncoding RNA, Acart, exerts a protective effect against cardiomyocyte injury by transactivating PPARγ signaling. However, the function of Acart in preadipocyte differentiation is unclear. To investigate the function of Acart in adipogenesis, a well-established preadipocyte, the 3T3-L1 cell line, was induced to differentiate, and Acart level was assessed during differentiation using quantitative real-time PCR. The biological role of Acart in adipogenesis was analyzed by assessing lipid droplet accumulation, PPARγ and CCAAT/enhancer-binding protein α (C/EBPα) expression, and 3T3-L1 cell proliferation and apoptosis after Acart silencing. We found that Acart level was promptly increased during preadipocyte differentiation in vitro. Acart was also significantly upregulated in obese mouse-derived subcutaneous, perirenal, and epididymal fat tissues compared with nonobese mouse-derived adipose tissues. Functionally, Acart depletion inhibited preadipocyte differentiation, as evidenced by a significant decrease in lipid accumulation and PPARγ and C/EBPα expression levels. Acart silencing also inhibited 3T3-L1 cell proliferation, whereas Acart overexpression accelerated 3T3-L1 cell proliferation and decreased cell apoptosis. Taken together, the current results reveal a novel function of Acart in regulating preadipocyte proliferation and differentiation.