Renal (pro)renin receptor contributes to development of diabetic kidney disease through transforming growth factor-β1-connective tissue growth factor signalling cascade

1. Transforming growth factor-β1 (TGF-β1) and connective tissue growth factor (CTGF) are expressed in renal glomeruli, and contribute to the development of diabetic nephropathy. Recently, we showed that (pro)renin receptor (PRR) is upregulated in the kidneys of the streptozocin (STZ)-induced diabetes rat model. We hypothesized that in the presence of hyperglycaemia, increased renal PRR expression contributes to enhanced TGF-β1-CTGF signalling activity, leading to the development of diabetic kidney disease. 2. In vivo and in vitro studies were carried out in Sprague-Dawley rats and rat mesangial cells (RMC). PRR blockade was achieved in vivo by treating STZ induced diabetes rats with the handle region peptide (HRP) of prorenin and in vitro by HRP or PRR siRNA in RMC. Angiotensin AT1 receptor blockade was achieved by valsartan treatment. 3. Results showed that expression of PRR, TGF-β1 and CTGF were upregulated in diabetic kidneys and RMC exposed to high glucose. Glucose exposure also induced PRR phosphorylation, a process that was inhibited by HRP, valsartan or PRR siRNA. HRP and valsartan significantly attenuated renal TGF-β1 and CTGF expression in diabetic animals and high glucose treated RMC. Similar results were observed in high glucose exposed RMC in response to PRR siRNA. TGF-β receptor blockade decreased CTGF expression in RMC. Combined administration of valsartan and PRR siRNA showed further reduction of TGF-β1 and CTGF expression in RMC. 4. In conclusion, PRR contributes to kidney disease in diabetes through an enhanced TGF-β1-CTGF signalling cascade.     

N-acetylcysteine prevents nitrosative stress-associated depression of blood pressure and heart rate in streptozotocin diabetic rats

Previous studies have indicated that cardiovascular abnormalities such as depressed blood pressure and heart rate occur in streptozotocin (STZ) diabetic rats. Chronic diabetes, which is associated with increased expression of inducible nitric oxide synthase (iNOS) and oxidative stress, may produce peroxynitrite/nitrotyrosine and cause nitrosative stress. We hypothesized that nitrosative stress causes cardiovascular depression in STZ diabetic rats and therefore can be corrected by reducing its formation. Control and STZ diabetic rats were treated orally for 9 weeks with N-acetylcysteine (NAC), an antioxidant and inhibitor of iNOS. At termination, the mean arterial blood pressure (MABP) and heart rate (HR) were measured in conscious rats. Nitrotyrosine and endothelial nitric oxide synthase (eNOS) and iNOS expression were assessed in the heart and mesenteric arteries by immunohistochemistry and Western blot experiments. Untreated diabetic rats showed depressed MABP and HR that was prevented by treatment with NAC. In untreated diabetic rats, levels of 15-F(2t)-isoprostane, an indicator of lipid peroxidation increased, whereas plasma nitric oxide and antioxidant concentrations decreased. Furthermore, decreased eNOS and increased iNOS expression were associated with elevated nitrosative stress in blood vessel and heart tissue of untreated diabetic rats. N-acetylcysteine treatment of diabetic rats not only restored the antioxidant capacity but also reduced the expression of iNOS and nitrotyrosine and normalized the expression of eNOS to that of control rats in heart and superior mesenteric arteries. The results suggest that nitrosative stress depress MABP and HR following diabetes. Further studies are required to elucidate the mechanisms involved in nitrosative stress mediated depression of blood pressure and heart rate.     

Tetrahydrobiopterin prevents endothelial dysfunction and restores adiponectin levels in rats

Oxidative stress induces endothelial dysfunction and hypoadiponectinemia. We previously reported that supplementation with tetrahydrobiopterin (BH4), one of the most potent naturally occurring reducing agents and an essential cofactor of enzymatic NO synthase (NOS), ameliorates endothelial dysfunction and reverses hypoadiponectinemia as a result of oxidative stress in rats. To further confirm this hypothesis, we investigated the effects of treatment with BH4 on endothelium-dependent relaxation and adiponectin levels during oxidative stress in fructose-fed rats, which provide an animal model for the metabolic syndrome. Ingestion of a fructose diet for 8 weeks significantly impaired endothelium-dependent arterial relaxation in aortic strips and decreased plasma adiponectin levels, as well as adiponectin mRNA levels within adipose tissue. However, oral supplementation with BH4 (10 mg/kg day) over the final 4 weeks leads to a significant partial reversal of impaired endothelium-dependent arterial relaxation, as well as normalization of plasma adiponectin and fat adiponectin mRNA levels. Moreover, BH4 treatment of the fructose-fed rats significantly reduced the lipid peroxidation content of aorta, heart, liver, and kidney tissues, which were increased in fructose-fed rats. This effect of BH4 treatment may be due to its function as a cofactor for eNOS, as well as its anti-oxidative effects. Thus, BH4 might show promise for the treatment of oxidative stress-induced disorders, including the metabolic syndrome.     

Polydatin attenuates renal fibrosis in diabetic mice through regulating the Cx32-Nox4 signaling pathway

We previously found that polydatin could attenuate renal oxidative stress in diabetic mice and improve renal fibrosis. Recent evidence shows that NADPH oxidase 4 (Nox4)-derived reactive oxygen species (ROS) contribute to inflammatory and fibrotic processes in diabetic kidneys. In this study we investigated whether polydatin attenuated renal fibrosis by regulating Nox4 in vitro and in vivo. In high glucose-treated rat glomerular mesangial cells, polydatin significantly decreased the protein levels of Nox4 by promoting its K48-linked polyubiquitination, thus inhibited the production of ROS, and eventually decreasing the expression of fibronectin (FN) and intercellular adhesion molecule-1 (ICAM-1), the main factors that exacerbate diabetic renal fibrosis. Overexpression of Nox4 abolished the inhibitory effects of polydatin on FN and ICAM-1 expression. In addition, the expression of Connexin32 (Cx32) was significantly decreased, which was restored by polydatin treatment. Cx32 interacted with Nox4 and reduced its protein levels. Knockdown of Cx32 abolished the inhibitory effects of polydatin on the expression of FN and ICAM-1. In the kidneys of streptozocin-induced diabetic mice, administration of polydatin (100 mg·kg⁻¹·d⁻¹, ig, 6 days a week for 12 weeks) increased Cx32 expression and reduced Nox4 expression, decreased renal oxidative stress levels and the expression of fibrotic factors, eventually attenuating renal injury and fibrosis. In conclusion, polydatin promotes K48-linked polyubiquitination and degradation of Nox4 by restoring Cx32 expression, thereby decreasing renal oxidative stress levels and ultimately ameliorating the pathological progress of diabetic renal fibrosis. Thus, polydatin reduces renal oxidative stress levels and attenuates diabetic renal fibrosis through regulating the Cx32-Nox4 signaling pathway.     

灯盏花素对大鼠糖尿病模型肾组织TGF-β1与CTGF表达影响的实验研究

目的　探讨灯盏花素对大鼠糖尿病模型肾组织转化生长因子 β1(TGF β1)与结缔组织生长因子 (CTGF)表达的影响。方法　建立STZ诱导的单侧肾切除糖尿病模型 ,随机分 :对照组、模型组、灯盏花素给药组 (2 0mg·kg-1·d-1,灌胃 )。观察 8wk后大鼠体重、肾重、肾重 /体重、2 4h尿白蛋白排泄率 (AER)、肾小球面积 (AG)和容量 (VG)及系膜区面积 (AM)的变化 ,并检测肾组织与尿MDA含量及肾组织SOD、CAT、GSH PX活性 ,通过免疫组化检测肾小球TGF β1与CTGF蛋白表达。结果　灯盏花素给药对大鼠糖尿病模型血糖、体重无明显影响 ,可明显抑制肾重、肾重 /体重、AER、AG、VG 及AM 的增加 (P <0 0 5 ) ;对肾组织及尿MDA含量的增加有明显抑制作用 (P <0 0 5 ) ,并明显提高肾组织SOD、CAT及GSH PX活性 (P <0 0 5 ,P <0 0 1)。免疫组化半定量分析显示 ,与对照组相比糖尿病大鼠肾小球TGF β1及CTGF表达明显增加 (P <0 0 1) ,灯盏花素给药对其有明显抑制作用 (P <0 0 5 )。结论　灯盏花素对大鼠糖尿病模型肾脏有明显保护作用 ,其机制部分与抑制肾组织TGF β1与CTGF过高表达有关     

罗格列酮对2型糖尿病大鼠心脏组织脂联素受体2单核趋化蛋白-1表达的影响

目的探讨罗格列酮对2型糖尿病大鼠心脏组织中脂联素受体2(AdipoR2)、单核趋化蛋白(MCP)-1表达影响。方法 36只雄性Wistar大鼠,随机分为3组:健康对照组(A组,10只),糖尿病组(B组,13只)和罗格列酮治疗组(C组,13只),采用高糖高脂饮食加小剂量链脲佐菌素(STZ)的方法诱导糖尿病模型。用反转录-聚合酶链反应(RT-PCR)的方法测定大鼠心肌AdipoR2mRNA、MCP-1mRNA的表达,用免疫组织化学法检测心脏组织中AdipoR2蛋白的表达。结果与A组比较,B组糖尿病大鼠心质量/体质量增加,MCP-1表达增加,血浆脂联素水平、心肌AdipoR2mRNA和蛋白表达显著降低。经罗格列酮治疗后,C组大鼠心质量/体质量、MCP-1mRNA降低,血浆脂联素水平、心肌AdipoR2mRNA和蛋白表达增加。结论 2型糖尿病大鼠心肌Adi-poR2表达水平降低,MCP-1的表达水平升高,罗格列酮上调2型糖尿病大鼠心肌AdipoR2的表达,并抑制MCP-1的过度表达从而延缓糖尿病心肌病的进展,可能是其心脏保护作用机制之一。     

罗格列酮对糖尿病大鼠肾脏结缔组织生长因子表达和排泄的影响

目的探讨罗格列酮对糖尿病大鼠肾脏结缔组织生长因子(CTGF)表达和排泄的影响。方法Wistar大鼠分为正常对照组、糖尿病模型组、糖尿病罗格列酮(4mg.kg-1.d-1)治疗组,每组8只,检测各组第1、4、6、8周尿CTGF排泄率(ELISA法),进行组间差异比较;于第8周处死大鼠,每组各5只,应用免疫组化检测肾皮质CTGF蛋白表达。结果第4、6、8周糖尿病大鼠治疗组及糖尿病模型组尿CTGF排泄率及第8周肾皮质CTGF蛋白表达水平较正常组明显升高,治疗组上述指标均较模型组低(P<0.01)。结论罗格列酮可抑制肾脏CTGF表达和排泄,这可能与其保护肾脏有关。     

2型糖尿病大鼠脂联素受体基因表达的相关性研究

目的研究2型糖尿病大鼠骨骼肌和肝脏脂联素受体的表达变化。方法将20只健康雄性SD大鼠随机分为糖尿病组(DM组)和对照组(NC组),每组10只,分别饲以高脂饲料和普通饲料。第13周末DM组大鼠一次性腹腔注射2%链脲佐菌素(STZ)溶液(STZ 25mg/kg,以0.1mol/L柠檬酸-柠檬酸钠缓冲液配制,pH=4.4),NC组腹腔注射等体积的无菌柠檬酸-柠檬酸钠缓冲液。第14周末进行葡萄糖耐量试验(OGTT)筛选成模大鼠,第25周末处死所有大鼠,取血检测空腹血糖、甘油三酯、胆固醇、脂联素、胰岛素水平,并计算胰岛素敏感指数(ISI),使用半定量反转录聚合酶链反应(RT-PCR)的方法分别检测2组大鼠骨骼肌和肝脏组织中脂联素受体(AR)mRNA表达水平。结果 DM组大鼠空腹血糖、甘油三酯、胆固醇、胰岛素水平高于NC组,脂联素水平和ISI低于NC组(P<0.05);DM组大鼠骨骼肌中AR1mRNA和肝脏组织中AR2mRNA的表达水平低于NC组(0.64±0.25与1.36±0.30,0.93±0.18与1.52±0.21;P<0.05),AR1和AR2表达水平分别与空腹血糖、甘油三酯、胆固醇、胰岛素、脂联素、ISI相关。结论 2型糖尿病大鼠AR mRNA的表达水平显著降低,与胰岛素敏感性密切相关。     

海藻溴酚化合物对糖尿病大鼠肾超微结构及结缔组织生长因子蛋白表达的影响

目的研究海藻溴酚化合物对糖尿病肾损伤大鼠结缔组织生长因子(CTGF)蛋白表达的影响。方法采用STZ注射制作糖尿病大鼠模型,随机分为对照组、模型组、化合物A和化合物B剂量组(0.5,10mg.kg-1),灌胃给药12周。处死大鼠,测血浆及肾组织中谷胱甘肽过氧物酶(GSH-Px)的活力及丙二醛(MDA)的含量;透射电镜法观察大鼠肾组织的病理改变;免疫组化法检测CTGF蛋白的表达。结果与对照组相比,模型组血浆及肾组织匀浆中GSH-Px活力下降,MDA含量升高。各干预组中GSH-Px的活力较模型组有升高的趋势,MDA含量有下降趋势。各干预组的CTGF平均吸光度值低于模型组。电镜下各干预组肾小球及肾小管病变较模型组减轻。结论海藻溴酚化合物A、B能提高糖尿病大鼠机体抗氧化水平,并能一定程度改善肾脏的病理变化,但其具体机制有待进一步探讨。     

Salviolone protects against high glucose-induced proliferation,oxidative stress,inflammation, and fibrosis of human renal mesangial cells by upregulating membrane metalloendopeptidase expression

As one of complications of diabetes mellitus, diabetic nephropathy is related to renal dysfunction. Membrane metalloendopeptidase (MME) is associated with the pathogenesis of diabetic nephropathy and exerts a protective function in high glucose (HG)-treated podocytes. Salviolone, one of important bioactive components from Salvia miltiorrhiza, possesses an anti-inflammatory activity. However, the roles of salviolone in renal mesangial cell dysfunction under HG condition remain unknown. The targets of salviolone in diabetic nephropathy were predicted by bioinformatics analysis. Relative mRNA level of MME was detected by qPCR in HG-treated human renal mesangial cells (HRMCs). Cell viability was analyzed using CCK-8 assay. Cell proliferation was investigated by EdU staining. Oxidative stress was evaluated by detection of ROS generation and levels of oxidative stress-related biomarkers. The inflammatory cytokines and fibrosis-related biomarkers were examined by ELISA. Our results showed that MME expression was decreased in diabetic nephropathy and HG-treated HRMCs. Salviolone increased MME level in HG-treated HRMCs. Salviolone mitigated HG-induced HRMC proliferation by increasing MME expression. Salviolone attenuated HG-induced ROS generation, MDA level increase, and SOD activity decrease through upregulating MME expression. Moreover, salviolone suppressed HG-induced increase of levels of TNF-α, IL-1β, IL-6, fibronectin, and collagen IV through upregulating MME expression. In conclusion, s alviolone attenuates proliferation, oxidative stress, inflammation, and fibrosis in HG-treated HRMCs through upregulating MME expression.     

脂联素对高糖环境下人肾小球系膜细胞增殖及氧化应激水平的影响

目的 探讨脂联素(Adiponectin,ADPN)对高糖环境下人肾小球系膜细胞(HMCs,human Mesangial Cells) 增殖及氧化应激水平的影响,揭示脂联素在糖尿病肾病中的保护作用.方法 ①体外培养HMCs:①将HMCs随机分为正常对照组(5.5 mmol/L 葡萄糖)、高糖组(30.0 mmol/L葡萄糖)、脂联素组(30.0 mmol/L葡萄糖+2.5 μg/ml脂联素),分别培养24、48、72 h后,运用四甲基偶氮唑蓝(MTT)法测定3组不同时间点HMCs的增殖情况.②将HMCs随机分为上述3组细胞,分别培养24、48、72 后运用硫代巴比妥酸法(TBA法)测定细胞上清液中MDA及SOD的含量.③再将HMCs随机分为上述3组细胞,分别培养24、48、72 h,运用实时荧光定量PCR(RT-PCR)测定HO-1 mRNA的表达,观察细胞氧化应激指标变化.结果 ①24 h高糖组与正常对照组比较细胞增殖无统计学差异(P>0.05),48、72 h两组比较,高糖组细胞增殖明显受抑制(P<0.05).加入脂联素促进细胞增殖,与高糖组比较差异有统计学意义(P<0.05);②24、48、72 h高糖组MDA含量均升高,SOD含量及HO-1 mRNA的表达均下降,与正常组比较差异有统计学意义(P<0.05).加入脂联素后,观察上述氧化应激指标均得到明显改善,差异有统计学意义(P<0.05).结论长期高糖刺激抑制人肾小球系膜细胞增殖,外源性加入脂联素可促进细胞增殖.高糖组均引起氧化应激指标升高,加入脂联素可降低系膜细胞氧化应激水平,提示其对细胞起保护作用.     

结缔组织生长因子在糖尿病肾病发生发展中的作用

目的 动态观察大鼠糖尿病肾病(DN)的不同阶段肾皮质结缔组织生长因子(CTGF)表达的变化及其与肾功能及肾组织形态学变化的相关性,探讨尿液中CTGF含量的检测作为DN诊断指标的意义.方法 以链脲佐菌素(STZ)诱导糖尿病大鼠为研究对象.63只大鼠分为糖尿病组33只和对照组30只.应用逆转录聚合酶链反应、免疫组织化学及蛋白质印迹法研究在糖尿病的不同时期肾皮质CTGF表达的动态变化,并研究其与DN早期肾肥大、ECM的聚积及后期肾小球硬化及肾间质纤维化之间的关系,同时以ELISA法检测糖尿病大鼠尿液中CTGF含量.结果 糖尿病大鼠肾皮质mRNA及CTGF蛋白质表达2周时开始增加,12周时达高峰,分别为(0.905±0.028)、(0.802±0.028),为正常对照组的4.38倍和9.97倍(均P＜0.05);其表达早期出现在肾小球,而后随着病程的发展出现于肾小管间质区域.相关性分析显示CTGF的表达与肾指数、肾小球体积、系膜基质指数、肾小管间质纤维化程度呈正相关(均P＜0.01);糖尿病大鼠尿液中CTGF的含量随着病程的发展逐渐升高,最高为(277.679±10.372)ng/L,与24h尿微量白蛋白、BUN、Cr呈正相关(均P＜0.01).结论 CTGF表达的增加贯穿了DN发病的整个过程,早期介导了肾肥大,肾小球ECM的积聚,晚期又介导了肾小球硬化及肾小管间质纤维化的发生;尿液CTGF的检测可以作为DN诊断的一个指标.     

TGF-β1、CTGF基因的过表达与早期糖尿病肾病关系的研究

目的:探讨转化生长因子(TGF)-β1、结缔组织生长因子(CTGF)在早期糖尿病肾病(DN)中的作用。方法:建立链脲佐菌素(STZ)诱导的糖尿病大鼠模型,随机分为正常对照组(NC)和糖尿病组(DM)。每周测量体质量,每2周测定血糖,于实验第8周末处死大鼠后测定相关的生化指标及肾功能指标,同时留取肾皮质液氮冻存,应用实时定量PCR方法检测肾皮质TGF-β1、CTGF的mRNA水平,用免疫组化法检测肾小球中TGF-β1和CTGF的蛋白表达情况,并进行半定量分析。结果:与NC组相比,DM组血尿素氮、24h尿量及尿微量蛋白、肾脏肥大指数明显升高(P<0.01),但血肌酐明显下降(P<0.01)。实时定量PCR及免疫组化结果显示,DM组较NC组TGF-β1、CTGFmRNA及蛋白表达量均明显增高。结论:TGF-β1与CTGF在肾病早期表达明显升高,对于评价DN进程具有重要意义。     

Protective effect of sun ginseng against diabetic renal damage

The effect of sun ginseng (SG, heat-processed Panax ginseng C. A. MEYER at 120 degrees C) on diabetic renal damage was investigated using streptozotocin-induced diabetic rats. The diabetic rats showed loss of body weight gain, and increases in food and water intake and urine volume, while the oral administration of SG at a dose of 50 or 100 mg/kg body weight/d for 15 d attenuated water intake and urine excretion induced by diabetes. In addition, the diabetic rats given SG at a dose of 100 mg/kg body weight showed significant decreases in serum glucose, serum glycosylated protein and urinary protein levels, suggesting that SG improves the abnormal conditions that lead to oxidative stress. Furthermore, SG significantly reduced advanced glycation endproduct (AGE) formation and thiobarbituric acid-reactive substance levels elevated in the kidneys of diabetic rats. This implies that SG would alleviate the oxidative stress under diabetes through the inhibition of lipid peroxidation. SG also reduced the overexpression of cyclooxygenase-2 and inducible nitric oxide synthase in the kidney induced by hyperglycemia via deactivation the activation of nuclear factor-kappa B. Furthermore, treatment with SG decreased the levels of 3-nitrotyrosine, carboxymethyllysine and receptors for AGE which increase under diabetes. These findings indicate that oxidative stress is increased in the diabetic rat kidney and that SG can prevent renal damage associated with diabetes by attenuating the oxidative stress.     

Long-term angiotensin II AT1 receptor inhibition produces adipose tissue hypotrophy accompanied by increased expression of adiponectin and PPARgamma

To clarify the mechanism of the effects of angiotensin II AT(1) receptor antagonists on adipose tissue, we treated 8 week-old male Wistar Kyoto rats with the angiotensin II AT(1) receptor antagonist Candesartan cilexetil (10 mg/kg/day) for 18 weeks. Candesartan cilexetil reduced body weight gain, decreased fat tissue mass due to hypotrophy of epididymal and retroperitoneal adipose tissue and decreased adipocyte size without changing the number of adipocytes. Candesartan cilexetil decreased serum leptin levels and epididymal leptin mRNA, increased serum adiponectin levels and epididymal adiponectin mRNA, decreased epididymal tumor necrosis factor alpha (TNFalpha) mRNA, and increased fatty acid synthase mRNA. Considered free of peroxisome proliferator-activated receptor gamma (PPARgamma) agonist activity, Candesartan cilexetil increased epididymal expression of PPARgamma mRNA. The effects of Candesartan cilexetil on adipokine production and release may be attributable to PPARgamma activation and/or decrease in adipocyte cell size. In addition, Candesartan cilexetil treatment increased the expression of epididymal angiotensin II AT(2) receptor mRNA and protein and decreased the expression of renin receptor mRNA. These results suggest that Candesartan cilexetil influences lipid metabolism in adipose tissue by promoting adipose tissue rearrangement and modulating adipokine expression and release. These effects are probably consequences of local angiotensin II AT(1) receptor inhibition, angiotensin II AT(2) receptor stimulation, and perhaps additional angiotensin II-independent mechanisms. Our results indicate that the activity of local renin-angiotensin system plays an important role in adipose tissue metabolism. The decrease in the pro-inflammatory cytokine TNFalpha and the increase in the anti-inflammatory adipokine adiponectin indicate that Candesartan cilexetil may exert significant anti-inflammatory properties.     

yy大黄酸对糖尿病大鼠肾脏还原型辅酶Ⅱ基因表达的影响

目的 观察大黄酸对糖尿病大鼠肾脏氧化应激的影响.方法链脲佐菌素(STZ)诱导的糖尿病肾病大鼠模型随机分为模型组与治疗组,治疗6周后,比较各组大鼠肾组织中丙二醛(MDA)含量和超氧化物歧化酶(SOD)活性,同时检测各组大鼠血糖、血肌酐、尿素氮、24 h尿蛋白定量等.采用逆转录-聚合酶链反应(RT-PCR)方法检测p22phox及p47phox的表达.结果治疗组较模型组明显改善尿清蛋白、尿素氮水平和肾脏肥大指数.肾脏MDA含量明显下降(P<0.05),SOD活性显著上升(P<0.05).与对照组比较,模型组p47phox和p22phox mRNA表达明显增多,大黄酸干预使其表达明显降低.结论大黄酸对2型糖尿病肾脏病变有一定的保护作用,其机制可能是通过抑制氧化应激反应,下调糖尿病大鼠p22phox及p47phox的表达对2型糖尿病模型大鼠肾脏产生保护作用.     

脂联素对高糖环境下RPE细胞氧化应激及凋亡的影响

目的 通过高糖环境下培养人RPE细胞建立RPE细胞的氧化应激模型,观察脂联素对RPE细胞各氧化应激指标及凋亡的影响,从而揭示脂联素对RPE细胞可能的保护机制.方法 将体外培养的人RPE细胞分为3组:正常对照组、高糖组、高糖+脂联素组,分别干预24、48、72 h.在倒置显微镜下观察RPE细胞形态变化,采用硫代巴比妥酸法测定MDA含量,用黄嘌呤氧化酶法检测SOD含量和活性,用荧光定量RT-PCR法测定p66Shc、Ho-1在各个时间点上的表达,通过流式细胞术检测RPE细胞的凋亡率.结果 与正常对照组相比,高糖组MDA含量显著上升,SOD含量显著下降(P<0.05),与高糖组相比,脂联素组MDA含量显著下降,SOD含量显著上升(P<0.05),并且呈时间依赖性.与正常对照组相比,高糖组Ho-1 mRNA表达增高;脂联素组较高糖组表达亦增高(P<0.05).与正常对照组相比,高糖组p66Shc mRNA表达增高;脂联素组较高糖组表达降低(P<0.05),呈时间依赖性.流式细胞术RPE细胞凋亡高糖组细胞凋亡率较正常对照组明显增加,而脂联素组细胞凋亡率较高糖组显著下降.结论 脂联素可通过减少p66Shc表达,从而减少线粒体ROS产生、增加Ho-1表达,增加抗氧化能力,减少氧化应激反应,减少细胞凋亡,对糖尿病RPE细胞起保护作用.