title: A selective cyclooxygenase-2 inhibitor decreases transforming growth factor-beta1 synthesis and matrix production in human peritoneal mesothelial cells.
abstract: High glucose concentration, which provides the chief driving force in peritoneal dialysis, has been considered to be an important initial factor that contributes to peritoneal thickening and fibrosis. Human peritoneal mesothelial cells (HPMCs) and the expansion of extracellular matrix (ECM) play important roles in the pathological process of peritoneal fibrosis. Peritoneal matrix accumulation is a characteristic of peritoneal fibrosis (PF). Continuous ambulatory peritoneal dialysis (CAPD) patients with upregulation of transforming growth factor-beta1 (TGF-beta1) in their drained effluent show an increased risk of PF. Inhibition of TGF-beta1 expression in human peritoneal mesothelial cells (HPMCs) may provide a potential treatment for PF. sc58236, a highly selective cyclooxygenase-2 (COX-2) inhibitor, reduces proteinuria and mRNA expression of TGF-beta1 and collagen III and IV in the remnant kidney, but their effects on ECM turnover in HPMCs are unknown. The aims of this study were to investigate the effects of sc58236 on TGF-beta1 expression and matrix production in HPMCs. HPMCs were cultured from human omentum by an enzyme digestion method. To examine the effect of sc58236 on TGF-beta1 and ECM secretion, HPMC were incubated in medium F12 with high concentration of D-glucose (4.25%) in the presence and absence of 20 microM sc58236. The mRNA expression of COX-2, TGF-beta1 and collagen I (Col I) were determined by semi-quantification reverse transcription PCR (RT-PCR). Prostaglandin E2 (PGE2) concentration in the culture medium was measured by enzyme-linked immunosorbent assay (ELISA). The protein of TGF-beta1 was determined by ELISA and the activity of TGF-beta1 present in the conditioned media was measured using the mink lung epithelial cell (MLEC) growth inhibition assay. Proteins of COX-2 and Col were determined by Western blot. The results showed that primary cultures of HPMCs do express the mRNA for COX-2 and stimulation of these cells with 4.25% D-glucose induced a marked increase in COX-2 mRNA expression and protein. PGE2 expression was obviously up-regulated with stimulation by 4.25% D-glucose. Addition of 20 microM sc58236 significantly inhibited PGE2 release into the culture medium. mRNA expression and bioactive and total protein of TGF-beta1 and Col I were significantly increased in HPMCs stimulated with 4.25% D-glucose compared to the control group with F12 media, which was reversed in the presence of sc58236 (20 microM). An obvious decrease in TGF-beta1 mRNA expression and bioactive and total protein were found in sc58236 treated groups compared to the group stimulated with 4.25% D-glucose. Exposure of HPMCs to sc58236 reduced Col I secretion. Sc58236 reduces the expression of TGF-beta1 in HPMCs stimulated by 4.25% D-glucose and reduces ECM production through PGE2 production. These studies suggest that sc58236, a highly selective cyclooxygenase-2 (COX-2) inhibitor, may have a specific role in ameliorating the course of progressive peritoneal fibrosis under long-term peritoneal dialysis states.
authors.affiliation: Department of Nephrology, Nephrology Institute of Central South University, 2nd Xiangya Hospital, Central South University, 139 Renmin Road, Changsha 410011, Hunan Province, P.R. China.
authors.forename: Hong
authors.initials: H
authors.lastname: Liu
authors.forename: Youming
authors.initials: Y
authors.lastname: Peng
authors.forename: Fuyou
authors.initials: F
authors.lastname: Liu
authors.forename: Jun
authors.initials: J
authors.lastname: Li
authors.forename: Xing
authors.initials: X
authors.lastname: Chen
authors.forename: Yinghong
authors.initials: Y
authors.lastname: Liu
authors.forename: Hao
authors.initials: H
authors.lastname: Zhang
mesh_terms: D002455:Cell Division / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D024042:Collagen Type I / Q000235:genetics*; D051546:Cyclooxygenase 2 / Q000235:genetics; D052246:Cyclooxygenase 2 Inhibitors / Q000494:pharmacology*; D004848:Epithelium / Q000187:drug effects; D005109:Extracellular Matrix / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D007770:L-Lactate Dehydrogenase / Q000032:analysis; D010529:Peritoneal Cavity / Q000166:cytology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D053773:Transforming Growth Factor beta1 / Q000235:genetics*
chemical_list: D024042:Collagen Type I; D052246:Cyclooxygenase 2 Inhibitors; D053773:Transforming Growth Factor beta1; D007770:L-Lactate Dehydrogenase; D051546:Cyclooxygenase 2