Fibroblast growth factor 21 regulates lipid accumulation and adipogenesis in goat intramuscular adipocyte

Fibroblast growth factor 21 (FGF21) plays a critical role in the regulation of lipid metabolism; however, its function in goat intramuscular fat (IMF) deposition remains unknown. To explore the role of FGF21 for goat IMF deposition, we performed gain and loss function of FGF21 in intramuscular adipocyte. Our results showed that overexpression of FGF21 mediated by adenovirus inhibits lipid accumulation of goat intramuscular adipocyte, accompanied by down-regulating the mRNA levels of peroxisome proliferator activated receptor γ (PPARγ), adipocyte fatty acid-binding protein 2 (aP2) and sterol regulatory element-binding protein 1 (SREBP1), but up-regulating counterpart of preadipocyte factor1 (Pref1). Conversely, siRNAs knocking down FGF21 promotes the expression of PPARγ and CCAAT/enhancer binding protein-α (C/EBPα) but suppressed that of lipoprotein lipase (LPL) and Pref1. Meanwhile, we found that FGF21 regulates the expression of many KLFs transcription factors, such as KLF3, 7, 9, 11, 14, and 16. These findings demonstrate a key role of FGF21 as a negative factor in the regulation of adipogenic differentiation in goat intramuscular preadipocyte.