Inhibition effect of PPARγ agonist on proliferation of human pterygium fibroblasts / 中华实验眼科杂志

ABSTRACT

Background Recurrence of pterygium is a common complication after the surgical excision of pterygium,and this procedure is related to cell proliferation,inflammation and neovascularization.Researches determined that rosiglitazone can suppress inflammation and neovaseularization and inhibit proliferation,hut few studies concerning the effect of rosiglitazone on pterygium were performed. Objective The aim of this study was to investigate the effect of peroxisome proliferator-activated receptor γ agonist on the proliferation and apoptosis of human pterygium fibroblasts(HPFs)in culture and search for a new drug to prevent and cure the recurrence after pterygium surgery. Methods Human pterygium samples were obtained during surgery and HPFs were cultured and purified using an explant method and 0.25%trypsin digestion,respectively.The identity of cultured HPFs was confirmed by immunohistochemistry using anti-vimentin and keratin antibodies.Rosiglitazone with the concentrations of 0(control),5,10,25,50,75,100,150,200,400μmol/L was then added in the culture medium for 12,24 or 72 hours.1%DMSO was used as blank control.The MTT method was used to assay the biologic effects of rosiglitazone on HPFs.Cell cycle distribution and apoptosis of HPFs after rosiglitazone treatment were studied by flow cytometic analysis.The expression of proliferating cell nuclear antigen(PCNA)mRNA in HPFs was detected by real-time PCR. Result Cultured HPFs radially migrated outward from the pterygium block,and then grew in long fusiform shape,showing positive response for vimentin and negative for keratin.The HPFs became round and thin with loose distribution after the addition of rosiglitazone.Following 25-125 μmol/L rosiglitazone administration for 12,48 or 72 hours,the A490 value of HPFs significantly declined with the increase of dosage(F=158.312,P=0.006)and lapse of time(F=1.924,P=0.135).Following the treatment of 25,75 or 125 μmol/L rosiglitazone for 24 hours,the number of HPFs in G0/G1 phase was markedly elevated;while the cell numbers in S phase decreased significantly in comparison with the control group(P＜0.05).The apoptotic rate of HPFs in the 25,75 and 125 μmol/L rosiglitazone groups significantly increased with the increase of rosiglitazone concentration(P＜0.05).Real-time PCR revealed that after 24 hours of rosiglitazone treatment,the expression of PCNA mRNA in HPFs was suppressed in a dose-dependent manner(F=3244.329,P＜0.05). Conclusion Rosiglitazone inhibits HPFs proliferation,arrests their cell cycle progression in G0/G1 phase,induces apoptosis of HPFs and depresses the synthesis of PCNA in a dose-and time-dependent manner.