Objective: To explore whether hydrogen sulphide (H2S) could protect human periodontal ligament stem cells (PDLSCs) from senescence and the possible underlying mechanisms.
Methods: Cell cycle assay and Ki-67 assay were used to measure proliferation of PDLSCs. Real-time polymerase chain reaction (PCR) was used to measure cellular senescence-related p16 and p21. Calcium influx was detected by measurement of Ca2+ imaging. In addition, we analysed the possible mechanisms underlying H2S acting on PDLSCs by microarray.
Results: The cell proliferation rate of aging PDLSCs decreased significantly. The expression of cellular senescence-related p16 and p21 significantly increased in aging PDLSCs. H2S donor (GYY4137) treatment increased the proliferation rate of senescence PDLSCs. Furthermore, the donor of H2S treatment effectively prevented cell cycle arrest of PDLSCs during the aging process and inhibited the expression of cellular senescence-related markers. Mechanically, H2S donor treatment could activate the calcium influx in PDLSCs. Moreover, pretreatment with TRPV4 inhibitors significantly attenuated the calcium influx induced by H2S donor treatment in PDLSCs. It also alleviated the protective effect of H2S on the senescence of PDLSCs.
Conclusion: H2S alleviated the senescence of human PDLSCs by TRPV4 channel mediated calcium flux. These results provide a potential strategy to deal with cell aging and may facilitate cell therapy for oral diseases.
Keywords: calcium flux; cell senescence; hydrogen sulphide; periodontal ligament stem cells; transient receptor potential cation channel subfamily V member 4.