MicroRNAs (miRNAs) play pivotal roles in intramuscular fat (IMF) deposition and determine animal meat quality. The study aimed to investigate the effect of miR-130b on adipogenesis in porcine intramuscular preadipocytes (PIMPA). In the study, PIMPA were isolated from longissimus dorsi muscle and cultured until 85%-90% confluence. The cells then subjected to adipogenic induction and transient transfections with miR-130b mimic, miR-130b inhibitor, and their corresponding controls (mNC and iNC). Oil red O staining was performed to detect lipid accumulation. Differentially expressed (DE) mRNAs were screened by transcriptome sequencing, and enriched functional pathways were identified through GO and KEGG analysis. The results demonstrated that numerous DE mRNAs were identified between the miR-130b mimic and mNC groups, which were mainly enriched in apoptosis, autophagy, and AMPK signaling pathways. Mechanistically, miR-130b overexpression significantly increased Bax expression, while reducing caspase-3 and Bcl-2 expression as well as Bcl-2/Bax ratio. It also, and tended to increase cleaved caspase-3/caspase-3 ratio, thereby activating apoptosis and suppressing lipid accumulation. Furthermore, these above results can be significantly reversed by miR-130b inhibition. In conclusion, our findings highlight that miR-130b inhibits lipid accumulation by activating apoptosis via Bcl-2/Bax/caspase-3 signaling pathway in PIMPA, providing a reliable molecular target for improving animal meat quality and ameliorating human obesity.
Li et al. (2026) studied this question.