Transcriptome Reveals the Promoting Effect of Beta-Sitosterol on the Differentiation of Bovine Preadipocytes

Abstract

Natural small molecule compounds play crucial roles in regulating fat deposition. Beta-sitosterol exhibits multiple biological activities such as cholesterol reduction and anticancer effects. However, its regulatory mechanism in the differentiation of bovine preadipocytes remains unclear. We identified potential associations of Beta-sitosterol with biological processes such as cholesterol regulation and lipid metabolism through the prediction of its targets. We utilized techniques such as Oil Red O staining, Western blotting, RNA-seq, and others to elucidate the promoting effect of Beta-sitosterol on the differentiation of bovine preadipocytes. Furthermore, reducing the expression of the most downregulated gene among differential expressed genes (DEGs), MGP, promotes the differentiation of bovine preadipocytes. After interfering with MGP, RNA-seq analysis on the sixth day of differentiation revealed that DEGs were most significantly enriched in the PPAR signaling pathway. In this pathway, the expression levels of genes related to adipocyte differentiation, including CD36, RXRα, RXRγ, FABP4, PLIN1, ADIPO, and CAP, were significantly upregulated (P < 0.01). Western blot and ELISA analysis on genes related to the PPAR signaling pathway showed that interfering with MGP increased the expression of proteins such as RXRα, indicating the possible activation of the PPAR signaling pathway. In summary, Beta-sitosterol may promote the differentiation of bovine preadipocytes by reducing the expression of MGP, thereby activating the PPAR signaling pathway.