Effects of rhPTH (1-34) on the proliferation and cell cycle of human keratinocyte HaCaT cells induced by tumor necrosis factor-α

Abstract

Objective To investigate the influence of recombinant human parathyroid hormone [rhPTH (1-34)]on the proliferation of HaCaT cells induced by tumor necrosis factor-α (TNF-α) in vitro.Methods Cultured HaCaT cells were treated with various concentrations of rhPTH (1-34) for different durations after incubation with recombinant human TNF-α of 10 g/L for 24 hours.MTT assay and flow cytometry were performed to detect the proliferation and cell cycle of HaCaT cells,respectively.Results As contrast phase microscopy showed,the growth of HaCaT cells was inhibited by rhPTH (1-34) along with a decrease in the growth speed.MTT assay showed a suppressed proliferation of HaCaT cells after being treated with rhPTH (1-34) of 0.05,0.2,0.8,3.2 and 12.8 pmol/L for 36 and 48 hours (P＜ 0.01 or 0.05).The percentage of cells at G1 phase in HaCaT cells markedly increased (all P ＜ 0.01 ),while that at S phase declined (all P ＜ 0.01 )after 48-hour treatment with rhPTH(1-34) of 0.2,0.8,3.2 and 12.8 μ mol/L.Conclusions rhPTH(1-34) has an obvious inhibitive effect on the proliferation of HaCaT cells induced by TNF-α in vitro,and the effect is in a dose-dependent manner. Key words: Keratinocytes; Parathyroid hormone; Psoriasis; Cell proliferation; Cell cycle