氮氧化物对中波紫外线照射下包皮成纤维细胞的保护作用

Protective effects of tempol on ultraviolet-B exposed human foreskin fibroblasts

目的研究中波紫外线(UVB)照射引起人包皮成纤维细胞氧化性损伤和对细胞增殖率、基质金属蛋白酶(MMP)表达的影响以及氮氧化物tempol的保护作用。方法体外原代培养的人包皮成纤维细胞接受UVB照射,同时加入或不加tempol,以生化方法检测细胞超氧化物歧化酶(SOD)活性和丙二醛(MDA)含量,以半定量RTPCR测定MMP1、MMP3mRNA表达水平。结果与未照射组比较,UVB使细胞增殖率下降至(84±8)%(P<0.05),使SOD活性降至(209.70±3.38)U/mg细胞蛋白(P<0.05),MDA堆积至(0.217±0.043)μmol/mg细胞蛋白(P<0.01),并上调了MMP1、MMP3mRNA的表达(P<0.01)。0.030～8.000mmol/Ltempol可部分甚至完全逆转上述效应,0.500mmol/Ltempol作用最强,细胞增殖率恢复至(107±15)%,SOD活性可达(287.04±8.45)U/mg细胞蛋白,MDA下降至(0.129±0.008)μmol/mg细胞蛋白,同时抑制了MMP1、MMP3mRNA的表达。结论tempol在体外对UVB引起的氧化性损伤以及成纤维细胞外基质成分过度降解有保护作用,因而有可能成为防治光老化的一种成分。

Objective To determine the effects of tempol（a nitroxide）, in the exposure of ultraviolet-B （UVB）, on cell proliferation, superoxide enzyme （SOD） activity, lipid peroxidation, and expression of matrix metalloproteinases （ MMP）-1, MMP-3 in human foreskin fibroblasts in vitro. Methods Fibroblasts were irradiated by a single exposure of 36 seconds to 40 mJ/cm^2 UVB and at the same time incubated with, or without, tempoland detected twenty-four hours later. SOD activity and lipid peroxidation,as shown by accumulation malondialdehyde （MDA） were detected by biochemical assay. Expression of MMP-1 and MMP-3 （mRNA level） were examined by Semi-quantitative RT-PCR. Results 40 mJ/cm^2 UVB significantly inhibited cell proliferation rate to （84±8）% （P〈 0.05） and SOD activity to （209.70±3.38） U/mg cell protein （P〈0.05）, significantly increased MDA level to （0. 217±0. 043） μmol/mg cell protein （P〈0.01） and stimulated MMP-1 and MMP 3 mRNA expression （P〈0.01）. Tempolat concentrations of 0.030 mmol/L to 8.000 mmol/L reversed these effects caused by UVB partly or completely and in proper concentration, the results had statistic significance compared with untreated control irradiated group （P〈0.05）. Tempol at concentration of 0. 500 mmol/l, had the strongest protective effect （ P 〈 0.01 ） . Conclusions Tempol has photoprotective properties against UVB irradiation in vitro. With antioxidant ability, tempol protects extracellular matrix of cutaneous fibroblasts and may be used as an anti-photoageing agent.