A research team led by Shan Zhu, with corresponding author Yan Y Sanders from the Department of Biomedical and Translational Sciences at Eastern Virginia Medical School, published findings on Mar. 3 that identify a role for the kinase p38 MAPK in activating fibrotic genes through epigenetic mechanisms in human lung fibroblasts.
The study is significant because it connects persistent activation of fibroblasts—a hallmark of idiopathic pulmonary fibrosis (IPF) and other age-related fibrotic diseases—to a specific molecular pathway involving p38 MAPK. This insight could inform new therapeutic strategies for conditions where excessive tissue scarring impairs organ function.
Researchers used IMR90 lung fibroblasts at different stages of cellular aging and primary cells from IPF patients to show that TGF-β1 increases expression of profibrotic genes α-SMA and Col3A1 in both young and near-senescent cells. However, near-senescent cells displayed a delayed but prolonged response via p38 MAPK when exposed to TGF-β1. Inhibiting p38 MAPK reduced both the transcription of these genes and the enrichment of H4K16 acetylation at their promoters, suggesting an epigenetic link between this signaling pathway and gene activation.
"These findings suggest that a p38 MAPK–dependent epigenetic mechanism is involved in fibroblast activation, supporting the therapeutic potential of p38 MAPK inhibition for treating age-related fibrotic diseases such as IPF," said the authors.
The paper emphasizes that persistent fibroblast activation and senescence are features common to IPF and similar disorders. The use of multiple experimental approaches—including western blotting, RT-qPCR, chromatin immunoprecipitation for H4K16ac, and primary patient-derived cells—adds translational relevance to the results. The authors note that further studies are needed to assess safety and efficacy in living organisms.
Next steps outlined by the researchers include identifying what sustains p38 signaling in aging fibroblasts, mapping chromatin changes downstream from this pathway, testing inhibitors in animal models, and exploring whether drugs targeting H4K16 acetylation can work together with kinase inhibitors to restore tissue repair without harming normal healing.
