Type I collagen alleviates tBHP-induced senescence in murine hippocampal neuronal HT22 cells through an F-actin/ferroptosis pathway.

PURPOSE: Neuronal senescence contributes to several age-related neurodegenerative diseases occurring with aging. Meanwhile, aging of our bodies is accompanied by the systemic dysregulation of type I collagen, the major component in the extracellular matrix. This study investigates whether type I collagen plays a protective role in neuronal senescence. METHODS: Cellular senescence was assessed by evaluating senescence-associated β-galactosidase staining, cell area, senescence-associated proteins, and senescence-associated secretory phenotypes (SASPs); ferroptosis was evaluated using C11-BODIPY 581/591 fluorescent probe, GSH, MDA, and total iron assay kits; fluorescently labeled phalloidin staining was employed to examine the changes in F-actin levels. RESULTS: Coating the cell plates with type I collagen attenuates the senescence of murine hippocampal neuronal HT22 cells and alleviates ferroptosis induced by tert-butyl hydroperoxide (tBHP), a donor of reactive oxygen species. Enhancing ferroptosis-associated signaling by inhibiting GPX4 or FSP1 pathways promotes senescence of HT22 cells, suggesting that the ferroptosis signaling accelerates senescence. Integrin β1, a major component of receptors for collagen, is downregulated in tBHP-treated cells but rescued by collagen. F-actin was markedly disrupted in tBHP-treated cells, while restored by collagen, it protects cells against tBHP-induced ferroptosis and senescence. CONCLUSIONS: Our study reveals an F-actin/ferroptosis axis for regulating senescence of HT22 neuronal cells by extracellular type I collagen. The findings here suggest new anti-senescent strategies targeting the F-actin and ferroptosis pathways.