Inhibitory effect of curcumin on proliferation of human pterygium fibroblasts

Abstract

In order to investigate the effect of curcumin on proliferation and apoptosis of human pterygium fibroblasts (HPF) in culture and search for a new method to prevent the recurrence after pterygium surgery, HPF was incubated with 0–160 μmol/L curcumin for 24–96 h. The MTT method was used to assay the biologic activities of curcumin at different time points and different doses. The expression of proliferating cell nuclear antigen (PCNA) in each group was detected by immunohistochemistry. The cell cycle distribution was detected by flow cytometry (FCM). Administration of 20–80 μmol/L curcumin for 24–72 h could significantly inhibit HPF proliferation in a dose-and time-dependent manner (P<0.05). After treatment with curcumin at different concentrations of 20, 40, 80 and 160 μmol/L for 24 h, FCM revealed there was a significant sub-G1 peak at each concentration. The number of HPF in G₀/G₁ phase was increased, while in S phase, it was decreased (P<0.05). At the concentration of 20–80 μmol/L, curcumin, in a dose-dependent manner (P<0.05), could inhibit the expression of PCNA in HPF. It was suggesterd that curcumin could significantly inhibit the proliferation of HPF, make HPF arrest in G₀/G₁ phase and induce the apoptosis of HPF in a dose-and time-dependent manner.

Keywords

curcumin / pterygium / human pterygium fibroblasts / proliferation inhibition

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