Implication of MicroRNA Regulation in Para-Phenylenediamine-Induced Cell Death and Senescence in Normal Human Hair Dermal Papilla Cells

The study investigated the effects of para-phenylenediamine (PPD) on normal human hair dermal papilla cells, revealing that PPD induced cell death and senescence through the alteration of specific microRNAs (miRNAs). Key findings included G2 phase arrest, increased reactive oxygen species (ROS) production, and senescence-associated β-galactosidase activity. PPD treatment led to significant downregulation of miR-146b-5p and miR-378, which are involved in cell survival and anti-senescence. The study identified 74 miRNAs with altered expression due to PPD, implicating the Wnt and MAPK signaling pathways in hair growth and cell proliferation regulation. These results suggested potential miRNA targets for treating PPD-induced cellular dysfunction.