The overlap between regeneration and fibrosis in injured skeletal muscle is regulated by phosphatidylinositol 3-kinase/Akt signaling pathway - A bioinformatic analysis based on lncRNA microarray

Injured skeletal muscle would go through a sequence of the pathological phases of degeneration, myogenesis and fibrosis. Growing evidence indicated that fibrotic and myogenic phases might overlap within the injured skeletal muscle in the early time after injury. However, the mechanism underlying this overlapping remains unclear. Here, we performed an lncRNA microarray to identify the activated pathways in mice muscle seven days after contusion. KEGG analysis indicated that phosphatidylinositol 3-kinase/Akt (PI3K/Akt) signaling cascade was predicted to be activated by lncRNAs. The top genes targeted by lncRNAs in PI3K/Akt signaling were subunits of laminin, collagen 5, and collagen 6, which participated in either myogenic or fibrotic process. Reverse transcriptase-polymerase chain reaction analysis and immunohistochemical stain further confirmed the prediction in silico. These results suggested that the overlap might be related to an activated PI3K/Akt pathway by lncRNA regulation.