CRISPR-Mediated POSTN Editing Modulates Proliferation, Apoptosis, and Molecular Profiles of Primary Rabbit Hair Follicle Stem Cells via the cAMP/PKA/CREB Signaling Pathway.

Hair follicle stem cells (HFSCs) are critical for hair follicle (HF) morphogenesis and cyclic hair regeneration. Periostin (POSTN), an extracellular matrix protein involved in tissue development and skin cell regulation, remains poorly characterized in HFSCs. In this study, we constructed CRISPR/Cas9 vectors targeting POSTN and validated their editing efficiency in primary HFSCs. POSTN editing significantly suppressed cell proliferation and promoted apoptosis. Transcriptomic analysis identified 988 differentially expressed genes (DEGs) enriched in immune responses and MAPK, PI3K-Akt, and cAMP pathways. Metabolomic analysis revealed 98 differential metabolites (DMs) associated with nucleotide metabolism and FoxO, AMPK, and cAMP pathways. Integrated multi-omics analysis showed extensive correlations between DEGs and DMs, and highlighted the cAMP pathway as the core regulatory axis. Western blot (WB) validation confirmed that POSTN editing reduced PKA and CREB phosphorylation, indicating inhibition of the cAMP/PKA/CREB signaling. These findings demonstrate that POSTN regulates HFSCs' proliferation and apoptosis partially via the cAMP/PKA/CREB pathway, providing novel insights into the functional regulation of HFSCs.