中文摘要：

目的探讨高糖作用下低密度脂蛋白（LDL）对人腹膜间皮细胞（HPMC）转分化及细胞外基质（ECM）蓄积的影响。方法（1）将HPMC随机分为对照组、LDL组（100mg／L）和LDL（100mg／L）＋LDL受体阻断剂乳铁蛋白（100mg／L）组，共培养24h。细胞免疫荧光法观察HPMC细胞上LDL受体的表达；油红O染色法观察HPMC对LDL的摄取情况。（2）将HPMC分别加入不同浓度LDL（0、25、50、100mg／L）培养24h，倒置相差显微镜下观察细胞形态的改变，细胞免疫荧光法观察细胞内OL平滑肌肌动蛋白（α-SMA）表达。（3）将静止细胞分为对照组（5．6mmol／L葡萄糖）、甘露醇组（M，2．18％甘露醇）、低糖组（LG，30mmol／L葡萄糖）、高糖组（HG，120mmol／L葡萄糖）和高糖＋LDL组（HG＋LDL，120mmol／L葡萄糖＋100mg／LLDL），共培养48h。实时定量PCR法检测d．SMA、E，cadherin和1型纤溶酶原激活物抑制物（PA1-1）mRNA的表达；Western印迹法检测α-SMA蛋白表达；ELISA法检测细胞培养上清中I型胶原（Col I）和PA1-1蛋白含量。结果（1）免疫荧光观察到LDL可以刺激HPMC细胞表达LDL受体。油红O染色法观察到HPMC能摄取LDL进入细胞内，加入乳铁蛋白能抑制LDL进入细胞内。（2）倒置相差显微镜下观察到，随LDL浓度增高，细胞问连接逐渐趋于松散，细胞呈现明显梭形成纤维细胞样形态；胞质内α-SMA荧光强度逐渐增强。与对照组相比，HG＋LDL组α-SMAmRNA和蛋白表达显著上调（均P〈0．05），E-cadherinmRNA表达显著下调（P〈0．05）。上述指标在HG组与HG＋LDL组、HG组与对照组之间表达量差异无统计学意义。（3）ELISA法检测结果显示，与HG组和对照组相比，HG＋LDL组细胞上清中Col I蛋白含量[（19．27±0．17）μg/L比（14．09±0．30）μg／L、（14．81±0．91）μg／L，均P〈0．05]及PAI-1含量[（498．24±76．91）ng／L比（342．19±30．43）μg／L、?

英文摘要：

Objective To investingate the effect of low-density lipoprotein （LDL） on epithelial -mesenchymal transition and extracellular matrix （ECM） accumulation in human peritoneal mesothelial cells （HPMCs）. Methods （1）HPMCs were randomly divided into control group, LDL group （100mg/L）and LDL （100 mg/L） ＋ lactoferrin （100 mg/L, LDL receptor blocking agent） group. After co-cultured for 24 h, the expression of LDL receptor in HPMCs was examined by immunofluorescenee staining, and the LDL uptake by HPMCs was observed with oil red O staining. （2）HPMCs were cultured with different concentrations of LDL （0, 25, 50, 100 mg/L）. After co-cultured for 24 h, the change of cell morphology was observed by inverted phase contrast microscope, and the expression of α-smooth muscle actin （α- SMA） was examined by immunofluorescenee. （3） HPMCs were randomly divided into control group （5.6 mmol/L glucose）, mannitol group （M, 2.18% mannitol）, low glucose group （LG, 30 mmol/L）, high glucose group （HG, 120 mmol/L） and HG ＋ LDL group （120 mmol/L glucose ＋ 100 mg/L LDL）. Co- cultured for 48 h, the mRNA expression of α-SMA, E-cadherin and type 1 plasminogen activator inhibitor （PA1-1） was detected by real-time quantitative PCR, the protein expression of α-SMA was detected by Western blotting, the content of type I collagen （Col I ） and PAl- 1 in superrlatant was detected by ELISA. Results （1） After co-cultured with LDL for 24 h, the expressin of LDL receptor was found on the cell membrane of HPMCs. Oil red staining showed that LDL could be uptaken into the cells and abolished by LDL receptor blocker. （2） HPMCs tended to be loosely intercellular connected to each ofher, and prsesnted significant formation of fibroblast-like spindle morphology. The cytoplasm immunofluorescence intensity of α- SMA gradually increased with the increase of LDL concentration. Compared to the control group, the expressions of α- SMA mRNA and protein were significantly increased, a