Sodium butyrate inhibits the proliferation of human pterygium fibroblasts

Objective To investigate the effects of sodium butyrate (NaB) on the proliferation of human pterygium fibroblasts (HPFs) in vitro. Methods Primary cultures and subcultures of pterygium fibroblasts were established in vitro. Cultured HPFs at the third to fifth passage were used in the experiment. HPFs were incubated with NaB at concentrations of 0mmol/l,1.25 mmol/l,2.5 mmol/l,5.0 mmol/l and 10.0 mmol/l for 12~72 h. MTT assay at 492nm was used to evaluate the biological activities of NaB at different concentrations and times. HPFs were incubated with NaB at concentrations of 0 mmol/l,1.25 mmol/l,2.5 mmol/l,5.0 mmol/l and 10.0mmol/l for 48 h. The apoptosis rate was detected by POD (In situ all Apoptosis Detection kit 1) assay. The cell cycle and apoptosis of HPFs exposed to different concentrations of NaB for 48 h were detected by flow cytometry (FCM). Results The proliferation of HPFs was inhibited when incubated with NaB (≥2.5mmol/l) for 12 h(P0.05). The inhibitory rate (IR) of 10.0mmol/l reached 41.35%. After 72 h,the IR of the different doses increased to 7.69%、31.67 %、47.96% and 63.20% in a dose-and time-dependent manner. The difference was significant when compared to the control group(P0.05). After being treated with NaB (≥2.5mmol/l) for 48 h,HPFs manifested typical apoptotic morphological features that were determined by POD assay. After being treated with NaB (≥2.5mmol/l) for 48 h,a significant Sub-G1 peak was detected by FCM. The cell percentage in the G0/G1 phase increased while that of the S phase decreased (P0.05). Conclusion The inhibition effect of NaB (≥2.5mmol/l) on HPFs was significant,and was dose-and time-dependent. The apoptosis of HPFs could be induced effectively and the cell cycle could be arrested by NaB in the G0/G1 phase.