OBJECTIVE To explore the anti-aging effects and possible regulatory mechanisms of Thermus thermophilus fermentation product(TTFP) by using the bleomycin-induced senescence model in human skin fibroblasts(HFF-1).

METHODS Cellular senescence in HFF-1 cells was induced using bleomycin. The optimal concentrations of TTFP for subsequent experiments were identified through the CCK-8 assay, which assessed cell viability. A range of experimental methodologies, including biochemical staining, flow cytometry, enzyme-linked immunosorbent assay(ELISA), real-time quantitative PCR, and Western blotting, were utilized to evaluate the impact of TTFP on several parameters. These included the expression of the senescence-associated marker β-galactosidase(SA-β-gal), the secretion of type I procollagen, apoptosis, levels of reactive oxygen species(ROS), mitochondrial membrane potential(MMP), cell cycle regulation, mRNA expression of cell cycle-related factors(P16, P21, TP53), the pro-inflammatory factor tumor necrosis factor-α(TNF-α), and the expression of proteins associated with the nuclear factor kappa-B(NF-κB) signaling pathway.

RESULTS Compared to the model group, the number of SA-β-gal-positive cells was significantly reduced and the secretion of procollagen type I was notably increased following TTFP intervention. Flow cytometry results indicated that the proportions of apoptotic cells and ROS-positive cells were significantly decreased, while the expression of inflammation-associated TNF-α and NF-κB pathway-associated proteins was markedly down-regulated.

CONCLUSION The TTFP can interfere with several cellular senescence markers, including reducing the activity of SA-β-gal, and promoting collagen secretion, inhibiting cellular ROS, and anti apoptosis. These effects may be associated with the modulation of anti-inflammatory signaling pathway.