Transcriptome analysis of chicken fibroblast following transforming growth factor β1-mediated activation.

Wooden Breast (WB) myopathy is one of the most challenging problems facing the broiler industry. Fibrosis characterized by extracellular matrix (ECM) proteins has been recorded as the prominent pathological feature within the pectoralis major muscles affected by WB. During the process of fibrosis, fibroblasts are the key players. Transforming growth factor-β1 (TGF-β1) serves as the principal cytokine inducing fibroblast to myofibroblast Transition (FMT). The mechanism of TGF-β in regulating fibroblast activation remains unclear despite growing evidence of its involvement. The objective of this study was to establish an in vitro chicken fibroblast activation model using TGF-β1 stimulation, and to explore the transcriptomic changes during this process. Results indicated that TGF-β1 upregulated the expression levels of FMT markers α-SMA, Collagen I, ACTA2, COL1A1, and FN1 in a dose-dependent and time-dependent manner (P < 0.05). Subsequently, RNA-seq analysis showed that a total of 1532 differentially expressed mRNAs (DEmRNAs) were identified between TGF-β1-induced chicken fibroblasts and the control group. We screened crucial biological processes and core DEmRNAs enriched in functional pathways, and established the protein-protein interaction network. Upregulated DEmRNAs including AMPD3, PDE10A and PDE4D, as well as downregulated DEmRNAs including NT5C1B, NT5M, ENTPD1, PDE1A, ADSL, DGUOK and PDE7B were identified as hub genes. Collectively, our current study provides a model framework for investigating the pathogenesis of WB myopathy and advances the mechanistic understanding of TGF-β1-induced fibrosis development in broiler chickens.