BBR can directly enter the cytoplasm of fibroblasts and act as a PPAR-γ agonist, up-regulating the nuclear translocation, DNA-binding activity, and transcriptional activity of PPAR-γ, and reversing PM2.5-induced collagen deposition, the expression of fibroblast markers (TGF-β1, FN, α-SMA, COI, and COIII), and the expression of E cadherin expression upregulation, promotes CD36 and AP2 mRNA expression, HGF and PTEN protein levels, and attenuates oxidative and inflammatory factor-mediated PF in BLM-induecd female ICR mice (Guan et al., 2018; Zhao et al., 2023). The gene discussed is ACTA1; the disease is pemphigus foliaceus.