红细胞生成素对慢性肾衰竭大鼠残肾组织归巢因子表达的影响

目的 观察红细胞生成素(EPO)对慢性肾衰竭(CRF)大鼠肾组织归巢因子表达的影响.方法 采用分阶段5/6肾切除制备大鼠CRF模型.实验动物随机分为3组:假手术组、CRF模型组和EPO治疗组.从第3周开始,治疗组大鼠每次皮下注射重组人EPO 50 IU/kg,每周3次,共6周.8周后检测各组大鼠血肌酐(Scr)、血尿素氮(BUN)、尿蛋白、血红蛋白(Hb)；采用实时荧光定量PCR、Western印迹和免疫组化方法检测残肾组织EPO及其受体(EPOR)、归巢因子及其受体(SDF-1、CXCR4、Ang-1、Tie2、SCF、c-Kit)的表达.结果 与模型组比较,EPO治疗可上调残肾组织归巢因子及其受体(SDF-1、CXCR4、Ang-1、Tie2、SCF、c-Kit)mRNA和蛋白的表达(均P＜0.05)；同时,EPO治疗还可上调残肾组织EPO及EPOR的mRNA和蛋白的表达(均P＜ 0.05).此外,EPO治疗还能下调大鼠Scr、BUN和尿蛋白水平(均P＜0.05),上调Hb水平(P＜0.05).结论 EPO能改善慢性肾衰竭大鼠的肾功能,这种作用可能与其激活残肾组织归巢因子而参与损伤肾脏的修复有关.     

慢性马兜铃酸肾病大鼠肾组织微血管损伤机制及温阳活血方的干预作用

目的:研究慢性马兜铃酸肾病大鼠肾组织微血管损伤机制及温阳活血方对其干预作用,探讨温阳活血方对慢性马兜铃酸肾病的保护作用机制.方法:将48只雄性SD大鼠随机分为5组.(1)正常对照组(n=8):予生理盐水灌胃;(2)模型组(n=10):按关木通水煎液10 ml·kg-1·d-1(相当于关木通40 g·kg-1·d-1,马兜铃酸A 2.6 mg·kg-1·d-1)给大鼠灌胃;(3)中药组(n=10):在模型组基础上,再予温阳活血方30 g·kg-1·d-1灌胃;(4)西药组(n=10):在模型组基础上,再予科素亚33.3 mg·kg-1·d-1灌胃;(5)中西药结合组(n=10):在模型组基础上,再予温阳活血方30 g·kg-1·d-1 科素亚33.3 mg·kg-1·d-1灌胃.20周末,光镜观察肾脏病理,采用CD 34免疫组化染色来反映肾组织微血管的损伤情况,实时PCR检测肾组织中Ang-1、Ang-2、Tie-2和VEGF mRNA的表达.结果:(1)与正常对照组比较,模型组大鼠肾组织CD34表达明显降低(P＜0.01);而治疗组大鼠肾组织CD34表达较模型组明显升高(P＜0.05),其中尤以中药组明显(P＜0.01);(2)与正常对照组比较,模型组大鼠肾组织Ang-1、Tie-2、VEGF mRNA表达明显降低(P＜0.05,P＜0.01),Ang-2表达明显升高(P＜0.01);而治疗组大鼠肾组织Ang-1、Tie-2、VEGF mRNA表达较模型组明显升高(P＜0.05,P＜0.01),中西药结合组Ang-2表达明显减少(P＜0.01).结论:慢性马兜铃酸肾病大鼠肾组织存在微血管的损伤,其损伤机制可能与Ang-1、Tie-2和VEGF mRNA的下调,Ang-2 mRNA上调有关,温阳活血方能明显改善微血管的损伤,对慢性马兜铃酸肾病大鼠肾脏具有保护作用.     

肥大细胞和干细胞因子在糖尿病肾病患者肾组织中的浸润表达及其意义

目的:探讨肥大细胞(MC)和干细胞因子(SCF)在糖尿病肾病(DN)患者肾组织中的浸润表达情况及其与肾间质损害和肾功能的关系。方法:选取经皮肾活检病理确诊的糖尿病肾病患者52例,按照肾间质病变严重程度将其分为轻度(n=21)、中度(n=20)和重度(n=11)3组,选取5例因肾脏外伤行肾脏切除患者的正常肾组织作为对照组。免疫组化法检测各组患者肾组织中MC、巨噬细胞的浸润和SCF、TGF-β_1的表达,原位杂交技术检测SCF基因的表达,并进行相关性分析。结果:(1)与对照组相比,轻、中、重度病变组肾间质中MC[(11.32±3.69)、(27.58±3.94)、(39.96±5.05)比(0.25±0.16),均P0.01]、巨噬细胞[(131.39±41.25)、(232.98±33.62)、(314.92±33.76)比(15.14±2.46),均P0.01]、SCF[(0.222±0.055)、(0.324±0.056)、(0.399±0.067)比(0.037±0.027),均P0.01]、TGF-β_1[(0.112±0.049)、(0.267±0.086)、(0.405±0.085)比(0.038±0.023),均P0.01]的浸润表达及MC脱颗粒水平[(13.38±4.64)%、(32.15±5.58)%、(52.55±5.64)%比(0.00±0.00)%,均P0.01]均显著增加,且随着间质损害的加重,上述细胞及因子的浸润表达逐渐增加,轻、中、重3组上述各检测指标两组间比较差异均有统计学意义(均P0.01)。(2)MC计数与血肌酐、尿NAG、RBP、β_2-微球蛋白和肾间质巨噬细胞、TGF-β_1的浸润表达呈显著正相关(r=0.729、r=0.799、r=0.786、r=0.681、r=0.889、r=0.906,均P0.001),与eGFR呈显著负相关(r=-0.665,P0.001)。SCF蛋白与MC计数、MC脱颗粒百分比、巨噬细胞和TGF-β_1的浸润表达也呈显著正相关(r=0.827、r=0.811、r=0.780、r=0.792,均P0.001)。结论:MC、SCF的浸润表达与DN患者肾间质损害程度密切相关,可能是DN患者肾功能不可逆进展的重要参与者。     

三七总苷对慢性肾衰竭大鼠肾损害防治作用的实验研究

目的:探讨三七总苷(PNS)对慢性肾衰竭(CRF)大鼠肾损害的防治作用.方法:单侧肾切除加重复阿霉素注射的方法建立CRF大鼠模型,PNS对照组和PNS治疗组随即给予PNS 400 mg·kg-1·d-1灌胃,正常对照组和模型对照组每日给予生理盐水灌胃.4周后处死大鼠,采用日本岛津CL-7200全自动生化分析仪检测Scr、BUN、SUA;采用瑞典AC100三分类血细胞分析仪检测Hb、RBC、HCT;肾组织HE染色后行光镜病理检查.结果:PNS对照组与正常对照组相比,大鼠的一般情况、肾功能、贫血指标及肾组织病理均无统计学差异.模型对照组与正常对照组相比,体重、生存率、RBC、Hb及HCT均显著降低(P＜0.01),肾重量、24 h尿量、Scr、BUN及SUA均显著增高(P＜0.01),肾小球及肾小管间质损害程度较重.PNS治疗组与模型对照组相比,生存率、RBC、Hb及HCT均显著提高(P＜0.01),体重、肾重量及24 h尿量无统计学差异,Scr、BUN及SUA均显著降低(P＜0.01),肾组织病理损害程度明显减轻.结论:PNS可减轻肾小球及肾小管间质损害,改善贫血,提高生存率,有望成为一种能够有效延缓慢性肾衰竭进展的中药.     

羟苯磺酸钙对慢性马兜铃酸肾病大鼠肾组织CD34和血管性血友病因子表达的影响

目的 观察羟苯磺酸钙对慢性马兜铃酸肾病(CAAN)大鼠肾小管周毛细血管内皮细胞特异抗原CD34和血管性血友病因子(vWF)表达的影响,探讨羟苯磺酸钙改善CAAN大鼠模型肾脏微循环障碍的作用和机制.方法 关木通水煎剂灌胃12周制作马兜铃酸肾病大鼠模型,随机分成未治疗组和治疗组.未治疗组(n=8)予饮用水灌胃4周;治疗组(n=8)予羟苯磺酸钙灌胃4周.另设健康对照组(n=8).实验第16周处死所有大鼠,留取血、尿、肾组织标本行生化、病理及免疫组织化学检查.结果 与未治疗组比较,治疗组肾功能明显改善,肾间质纤维化程度减轻[(38.22±5.17)×103比(69.97±17.69)×103,P＜0.01],CD34阳性表达显著增加[(16.72±4.17)×103比(3.19±1.40)X103,P＜0.01];vWF阳性表达显著减少[(10.16±1.67)×103比(18.66±4.65)×103,P＜0.01)].结论 羟苯磺酸钙能增加CAAN大鼠肾组织CD34的阳性表达,增加肾小管周围毛细血管密度;减少CAAN大鼠肾组织vWF的阳性表达,减少微血栓形成.     

高压氧对大鼠缺血再灌注损伤肾FasL和半胱氨酸蛋白酶3表达的影响

目的 研究高压氧(HBO)对大鼠缺血再灌注损伤(IRI)肾细胞凋亡相关基因(FasL)和细胞凋亡执行蛋白半胱氨酸蛋白酶3(caspase-3)表达的影响,并探讨其作用机制.方法 健康SD雄性大鼠随机分为假手术组(n=8)、IRI组(n=8)和IRI+HBO组(n=8).采用夹闭双侧肾动脉方法建立IRI模型.IRI+HBO组分别在再灌注后lh、24 h、48 h给予HBO处理,末次HBO后取双肾组织测定各组大鼠肾组织匀浆超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量 ;采用实时荧光定量PCR和免疫组织化学染色方法分别测定肾组织FasL mRNA、caspase-3蛋白表达.结果 与假手术组比较,IRI组SOD活性下降(P＜0.05),MDA含量升高(P＜0.05),经HBO治疗后SOD活性升高(P＜0.05),MDA含量降低(P＜0.05).FasL mRNA、caspase-3蛋白在假手术组呈低水平表达,而在IRI组表达显著上调(P＜0.01),IRI+HBO组表达较IRI组显著下调(P＜0.01).结论 大鼠肾缺血损伤后随着再灌注时间延长FasL mRNA 、caspase-3蛋白表达显著上调.早期HBO治疗后可以使FasL mRNA、caspase-3蛋白表达明显下调,抑制细胞凋亡,保护肾脏.     

诱导体内产生一氧化碳对小鼠心脏移植排斥反应的抑制作用

目的 探讨用二氯甲烷(MC)诱导同种心脏移植受鼠体内产生CO以减轻排斥反应及延长受鼠存活时间的作用,并探讨其机制.方法 以C57BL/6小鼠为供者,Balb/c小鼠为受者,建立小鼠颈部异位心脏移植模型.实验分3组,MC 1组和MC 2组受鼠分别于术前1d至术后6d和至13 d,用含MC的橄榄油100 mg/kg灌胃,移植对照组受鼠术前1d至术后6d用等体积不含MC的橄榄油灌胃.术后监测移植心存活时间;检测受鼠肿瘤坏死因子α(TNF-α)、白细胞介素10(IL-10)及叉状头螺旋转录因子(Foxp3)mRNA及蛋白的表达;检测移植心脏细胞间黏附分子-1(ICAM 1)及胱天蛋白酶3的表达;观察移植心组织病理学变化.结果 受鼠碳氧血红蛋白(COHb)浓度在MC灌胃前为(0.85±0.28)％,灌胃后3h达到峰值(5.24±0.45)％(P＜0.01).移植对照组、MC 1组、MC2组移植心脏的平均存活时间分别为6.3、12.1和19.4d,两MC组移植心存活时间较移植对照组明显延长(P＜0.01).与移植对照组相比,两MC组TNF-a和TNF-α mRNA、ICAM-1及胱天蛋白酶3的表达均得到明显抑制(P＜0.01);移植心肌淋巴细胞和单核细胞浸润的程度得到明显减轻,尤以MC2组最为明显.各组间血清IL-10和IL-10 mRNA及Foxp3蛋白和Foxp3 mRNA表达的差异均无统计学意义(P＞0.05).结论 诱导同种心脏移植受鼠体内产生CO能明显减轻排斥反应,延长移植心存活时间,其主要机制可能与CO的抗炎症和抗凋亡功能密切相关,而并不依赖于Foxp3表达的上调.     

急性重症胆管炎大鼠肝组织高迁移率族蛋白-1对肿瘤坏死因子-表达的影响

目的 探讨急性重症胆管炎(ACST)大鼠肝组织高迁移率族蛋白1(HMG-1)改变及其对肿瘤坏死因子(TNF-α)表达的调节作用.方法 通过制作ACST大鼠模型,正丁酸钠干预,不同时相点检测肝组织HMG-1及TNF-α表达,同时观察肝功能及结构改变.结果 AGST组12～24 h肝组织HMG-1和TNF-a mRNA表达均显著增强(P＜0.05或0.01).正丁酸钠处理可显著抑制ACST后12～24 h肝组织HMG-1 mRNA表达(P＜0.01),并明显下调肝组织TNF-α mRNA表达及TNF-α水平(P＜0.05或0.01),同时血清谷丙转氨酶(ALT)水平显著降低(P＜0.05或0.01),肝脏的病理形态得到明显改善.结论 ACST大鼠肝组织HMG-1表达可促进局部TNF-α的合成与释放,从而诱导ACST大鼠急性肝功能损害.     

δ阿片受体激动剂对脓毒症大鼠肝细胞凋亡及肝组织bcl-2和caspase-3表达的影响

目的 观察δ阿片受体激动剂D-丙2 ,D-亮5脑啡肽(D-Ala2 ,D-Leu5-enkephali,DADLE)对脓毒症大鼠肝细胞凋亡及肝组织bcl-2和caspase-3表达的影响,探讨DADLE对肝脏保护作用的可能机理.方法 采用盲肠结扎加穿孔(CLP)法制作大鼠脓毒症模型,SD大鼠54只(雌雄不限),采用随机数字表法随机分为CLP组(n=18)、DADLE组(n=18)和假手术组(n=18).在不同时间点(2、4及6 h)处死大鼠,原位末端标记法检测肝细胞凋亡情况,免疫组化法检测肝组织中bcl-2及caspase-3蛋白表达的动态变化并观察肝脏的病理改变.结果 CLP组大鼠肝组织病理损害明显较假手术组严重,DADLE组肝脏的病理变化明显改善; CLP组大鼠肝组织细胞凋亡指数明显较假手术组升高(P＜0.01),以4 h最显著(P＜0.01),DADLE 组各时相肝细胞凋亡指数均明显降低(P＜0.01); CLP组大鼠肝组织caspase-3蛋白的表达强度比假手术组明显增强(P＜0.01),而bcl-2蛋白的表达则明显减弱(P＜0.05); DADLE组肝组织caspase-3蛋白的表达强度较CLP组明显减弱(P＜0.01),而bcl-2蛋白的表达则明显增强(P＜0.05).肝组织caspase-3的表达与肝细胞凋亡指数呈正相关(r=0.83,P＜0.01),bcl-2的表达与肝细胞凋亡指数呈负相关(r=-0.65,P＜0.01).结论 DADLE能明显改善脓毒症大鼠肝脏的病理变化,其作用机理可能与DADLE下调caspase-3表达、上调bcl-2表达,从而抑制肝细胞凋亡有关.     

肥大细胞参与蛋白负荷肾病大鼠肾间质的纤维化

目的 观察肥大细胞（MC）在蛋白负荷肾病肾间质纤维化大鼠模型肾脏的分布并探讨其与蛋白尿所致肾间质纤维化、肾间质转化生长因子β1（TGF-β1）及干细胞因子（SCF）表达的关系。 方法 60只SD大鼠行右肾全切术后，模型组腹腔注射牛血清白蛋白（BSA）复制蛋白负荷肾病大鼠的模型（n=30），对照组腹腔注射生理盐水（n=30），分别于模型成功后第3、7和11周，随机处死10只大鼠，检测尿蛋白和血生化指标。采用甲苯胺蓝组织化学和糜蛋白酶（chymase）免疫组化的方法观察肥大细胞在肾脏的浸润。采用免疫组化法检测TGF-β1、SCF在肾组织的表达，并分析它们之间及与蛋白尿所致肾间质纤维化的相关性。 结果 模型组大鼠随着BSA注射量的增加, 尿蛋白量（24 h）增加，第7周达到高峰[(199.1±98.4) mg], 以后开始下降，第11周为(133.7±67.8) mg。在模型组大鼠的肾皮质、髓质均可见甲苯胺蓝染色阳性及chymase阳性的肥大细胞, 以间质纤维化区域最为多见。随着肾间质纤维化的加重, 肥大细胞数目增多，各时间点模型组大鼠与对照组差异均有统计学意义（P < 0.05）。TGF-β1及SCF主要在肾小管、间质、部分系膜细胞及壁层上皮细胞表达，随时间的延长表达量增加，各时间点模型组大鼠与对照组差异均有统计学意义（P < 0.05）。肥大细胞的数量与肾间质纤维化的程度、TGF-β1和SCF的表达均呈正相关(r分别为0.722、0.521、0.916, 均P < 0.01)。 结论 肥大细胞浸润与蛋白负荷肾病大鼠肾间质纤维化程度密切相关。蛋白尿可能通过SCF介导肥大细胞到肾脏，释放chymase，促进肾组织TGF-β1表达，介导蛋白尿所致的肾间质纤维化。     

Role of stem cell factor and mast cells in the progression of chronic glomerulonephritides.

BACKGROUND: Mast cells (MCs) have been implicated in the pathogenesis of atherosclerosis and tissue fibrosis. However, the role of MC in the development of renal fibrosis has not been fully elucidated. Stem cell factor (SCF; the ligand for MC c-kit receptor) is thought to attract and activate MCs. METHODS: The intensity of MC infiltration and SCF expression in renal biopsies from 56 patients with different forms of primary and secondary glomerulonephritis and five controls were investigated by immunohistochemistry, using a monoclonal anti-human MC tryptase antibody and a polyclonal antihuman SCF antibody. RESULTS: A large number of MCs were detected in the renal interstitium of the diseased kidneys. Immunostainable SCF was detected in tubular as well as interstitial cells. MC infiltration was significantly higher in glomerulonephritis (16.9 +/- 10.2 cells/field) compared with controls (2.8 +/- 2.1 cells/field, P = 0.03). Similarly, immunostainable SCF was 0.6 +/- 0.3% for controls and 3.3 +/- 2.1% in the glomerulonephritis group (P = 0.02). MC infiltration was highly correlated with SCF expression in diseased kidneys (r = 0.93, P = 0.0001). Double immunostain showed them to colocalize in some interstitial cells. Analysis of MC proliferation [proliferating cell nuclear antigen (PCNA) positivity] and apoptosis (in situ end labeling of DNA) showed these cells to be terminally differentiated. Both MCs and SCF were correlated with interstitial fibrosis (R = 0.71 for MC and R = 0.62 for SCF, P = 0.0001) and interstitial alpha-smooth muscle actin (R = 0.69 for MC and R = 0.60 for SCF P = 0.0001). Using regression analysis, the number of MC infiltration was found to be a very powerful determinant of interstitial fibrosis in the glomerulonephritis group (R2 = 91.4%). CONCLUSION: MCs as an infiltrating hematopoietic cell and its growth factor (SCF) seem to be up-regulated in glomerulonephritis, and may play a role in the development of renal fibrosis.     

Effects of 1,25-dihydroxyvitamin D3 on macrophage chemo taxis inhibitory factor and nuclear factor-κB/P65 in obstructive nephropathy rats

Objective To investigate the expression of macrophage migration inhibitory factor(MIF) and nuclear factor-κB/P65 (NF-κB/P65) in the kidneys of unilateral ureteral occlusion (UUO) model rats and the effect of 1,25-dihydroxyvitamin D3 on the expression. Method The cell model of obstructive nephropathy was established by renal tubular epithelial cells treated with TGF- beta 1. Thirty healthy adult male SD rats were randomly divided into 3 groups: sham operation group (n=10), UUO group (n=10) and 1,25-dihydroxyvitamin D3 group (n=10, UUO rats treated with 1,25-dihydroxyvitamin D3 by lavage 2 days before operation)．The rats in sham group and UUO group were treated with equal normal saline by lavage. Serum creatinine (Scr) and histopathological changes were tested at week 2. The expressions of collagen Ⅳ (ColⅣ), macrophage marker antigen ED-1, MIF and NF-κB/P65 in renal issue were measured by immunohistochemistry. The MIF mRNA was detected by real-time PCR and the protein expressions of MIF, NF-κB inhibitor α (IKBα) and p-IKBα were measured by Western blotting. In renal tubular epithelial cells (NRK52E) the expressions of MIF and NF-κB were detected by immunocytochemistry, and the the protein expression of MIF and the activation of IKBα were teasted by Western blotting. Results Compared with those in sham group, in model group rats had increaced Scr, tubulointerstitial damage area and expressions of ED-1 and ColⅣ, and up-regulated mRNA and protein expressions of MIF (all P＜0.05). Moreover, the amount of NF-κB/P65 nuclear positive cells and p-IKBα expression were significantly increased while the expression of IKBα decreased in model group (all P＜0.05). NRK52E cells had higher expressions of MIF, NF-κB and p-IKBα, and lower IKBα in model group than those in control group (all P＜0.05). After the application of 1,25-dihydroxyvitamin D3, those above effects were inhibited (all P＜0.05). The results of cell model and animal model were in agreement. Conclusions The expressions of MIF and the activation of NF-κB/P65 in UUO rats increased significantly. 1,25-dihydroxyvitamin D3 may ameliorate the progression of renal tubulointerstitial inflammation and renal fibrosis by intervening the expression of MIF, inducing phosphorylation of IKBα and decreasing the activation of NF-κB/P65.     

Role of 12 ? lipoxygenase in the process of diabetic mesangial hypertrophy

Objective To explore the role of 12 - lipoxygenase (12 - LO) in the pathogenesis of diabetic renal mesangial cells (MC) hypertrophy and its related mechanisms. MethodsWT and 12-LO knockout mice were induced as type 1 diabetes to investigate the renal hypertrophy and expression of p21, p27 in glomeruli. The ratio of total protein to cell number was detected as cellular hypertrophy diagnosis to explore the role of 12-LO in hyperglycemia induced mesangial cellular hypertrophy. Real-time PCR and Western blotting were used to detect the changes of p21 as well as p27 induced by 12(S)-HETE which was 12 - LO metabolic product. Results12(S) - HETE promoted p21 gene expression (P＜0.05), increased p21 and p27 protein levels in MC (all P＜0.05), therefore induced cellular hypertrophy (P＜0.05). MC from 12-LO knockout mouse showed less hypertrophy and decreased expression of p21 and p27 compared with WT MC under high glucose condition (all P＜0.05). On the contrary, over - expression of 12 - LO significantly enhanced p21 and p27 protein expression in MC (P＜0.01). Compared to WT mice, 12-LO knockout mice showed less renal hypertrophy and decreased expression of p21 and p27 in glomeruli induced by hyperglycemia (all P＜0.05). Conclusion12-LO involves in the process of diabetic renal hypertrophy through regulating the expression of p21 and p27.     

Effects of irbesartan on the expression of hypoxia-induced factor 1α and connective tissue growth factor in the kidney of unilateral ureteral ligation operation model rats

Objective To investigate the expression of hypoxia-induced factor 1α (HIF-1α)and connective tissue growth factor (CTGF) in the kidneys of unilateral ureteral ligation operation (UUO)model rats and the effect of irbesartan on the expression. Methods Thirty healthy adult male SD rats were randomly divided into 3 groups: sham operation group (n＝10), UUO group (n＝10) and irbesartan group (n＝10, UUO rats treated with irbesartan by lavage 2 days before operation). The rats in sham group and UUO group were treated with equal normal saline by lavage. Renal function, histopathological changes, urinary protein of 24 hours in rats at week 2 were measured. In situ hybridization and Western blotting were applied to measure the expression of HIF-1α and CTGF. Results At week 2, the levels of BUN, Scr and the expressions of HIF-1α and CTGF were significantly increased in UUO group compared with those in sham group (all P＜0.01). There was significant positive correlation between HIF-1α mRNA and CTGF mRNA (r＝0.697, P＜0.01). Compared with UUO group, the levels of urine protein and Scr were significantly decreased [(103.44±8.76) mg/24 h vs (278.23±26.15) mg/24 h, P＜0.01; (109.15±3.93) μmol/L vs (185.04±13.45) μmol/L P＜0.01], and renal tubulointerstitial lesion area became smaller (0.28±0.02 vs 0.51±0.05, P＜0.01) in irbesartan group. The expression of HIF-1α mRNA and protein was also significantly decreased after the treatment of irbesartan (all P＜0.01). Conclusions The expressions of HIF-1α and CTGF in UUO rats increase significantly. Irbesartan can improve renal fibrosis through down-regulating the expression of HIF-1α and CTGF.     

单侧输尿管梗阻大鼠肾脏转化生长因子β受体亚型表达的变化

目的 探讨转化生长因子β（TGF-β）Ⅰ型受体（RⅠ）、Ⅱ型（RⅡ）受体以及下游Smad蛋白在单侧输尿管梗阻（UUO）大鼠模型肾脏中表达及意义。 方法 90只雌性Wistar大鼠随机分为正常对照组（CON组）、假手术组（SOR组）和单侧输尿管梗阻组（UUO组）,分别于术后1、3、7、14、21 d处死,检测各组大鼠肾功能;PAS与Masson染色观察大鼠肾间质病理形态改变;实时定量PCR基因芯片分析正常大鼠和肾间质纤维化大鼠肾组织TGF-βⅠ、Ⅱ、Ⅲ型受体及Smad蛋白家族表达。筛选出差异表达的受体亚型,进一步应用实时荧光定量PCR、蛋白免疫印迹法、免疫荧光法检测和验证筛选出的差异受体亚型在不同分期肾间质纤维化大鼠肾组织的分布和表达。 结果 与CON组相比,UUO组大鼠的Scr及BUN于术后3 d开始升高（P < 0.05）,第21天达峰值（P < 0.01）;UUO组术后3 d肾间质可见明显炎性细胞浸润;14 d后出现明显肾小管萎缩;21 d可见明显肾间质纤维化。UUO组肾组织TGF-βⅠ型受体ALK-5、ALK-7和TGF-βRⅡ的mRNA表达于术后3 d上升并随梗阻时间延长逐渐增加（P < 0.05）,于14 d达到峰值（均P < 0.01）;ALK-6的mRNA表达于术后3 d下降（P < 0.05）并随梗阻时间延长逐渐减少,于14 d达谷值（P < 0.01）。ALK-5、ALK-6、ALK-7和TGF-βRⅡ蛋白表达与基因表达一致。Smad2/3及磷酸化（p）-Smad2/3的蛋白表达于术后3 d上升（均P < 0.05）并随梗阻时间延长逐渐增加,于14 d达到峰值（均P < 0.01）。 结论 在肾间质纤维化进展中不同TGF-β受体亚型存在不同的变化规律并与肾间质纤维化进展密切关联。     

氧化应激介导糖尿病大鼠肾小管上皮细胞转分化及普罗布考的干预作用

目的 研究氧化应激在糖尿病肾病（DN）大鼠肾小管上皮细胞转分化中的作用,探讨抗氧化剂普罗布考对大鼠DN的肾脏保护作用。 方法 30只雄性SD大鼠随机分为正常对照组、DN组和普罗布考干预组（1％普罗布考饮食）,每组10只。分别于第3周、第8周及第12周检测24 h尿蛋白（UTP）;12周末检测各组大鼠血糖、血脂（胆固醇、三酰甘油）、Scr、肌酐清除率（Ccr）、肾脏组织匀浆液丙二醛（MDA）含量及谷胱甘肽过氧化物酶（GSH-Px）活性。肾组织病理切片行 HE和Masson染色;采用免疫组化和Western印迹检测肾组织核转录因子Sp1、α平滑肌肌动蛋白（α-SMA）及E钙黏蛋白（E-cadherin）表达。 结果 与正常对照组比较,DN组血糖、Scr、肾组织匀浆MDA和24 h UTP水平显著增高（均P < 0.01）,Ccr显著降低（P < 0.01）;肾组织肾小管损伤分数、α-SMA和 Sp1蛋白表达水平明显增高（均P < 0.01）;肾组织E-cadherin蛋白表达明显下调。肾组织MDA含量分别与α-SMA及Sp1蛋白表达呈正相关（r ＝ 0.896,P < 0.01;r ＝ 0.862,P < 0.01）,与E-cadherin蛋白表达呈负相关（r = -0.673, P < 0.01）。普罗布考干预组Scr、24 h UTP、肾组织MDA、肾小管损伤分数及肾组织α-SMA、 Sp1蛋白表达水平较DN组均明显降低（均P < 0.01）;Ccr和肾组织E-cadherin蛋白表达水平较DN组均明显增加（均P < 0.01）。 结论 氧化应激在DN大鼠肾小管上皮细胞转分化中起重要作用。普罗布考可能通过抗氧化、下调肾组织Sp1蛋白表达及抑制肾小管上皮细胞转分化延缓DN大鼠肾脏病变进展。     

JAK-STAT通路在小鼠单侧输尿管梗阻模型肾间质纤维化中的作用

目的 探讨Janus蛋白酪氨酸激酶-信号转导子和转录激活子(JAK-STAT)通路在小鼠单侧输尿管梗阻(UUO)模型.肾间质纤维化过程中的作用.方法 选用30只雄性Balb/c小鼠建立小鼠UUO模型(n=24)和假手术小鼠(n=6),术后第1、4、7和14天检测JAK-STAT磷酸化情况.另把18只雄性Balb/c小鼠随机分为假手术组、UUO模型组和治疗组,每组各6只.治疗组在建模前2 h开始给予选择性JAK2抑制剂AG490治疗,每天1次;模型组仅注射溶媒.术后第14天处死动物.组织学评估肾小管损伤和.肾间质纤维化程度;免疫组化检测肾脏巨噬细胞浸润和α-SMA表达;RT-PCR检测Ⅲ型胶原和单核细胞趋化蛋白(MCP)1 mRNA表达;Western印迹检测JAK2和STATl磷酸化.结果 JAK2-STAT1在UUO模型中被激活,其磷酸化水平与病情、肾小管组织学损害以及.肾间质纤维化相一致.AG490能显著抑制JAK2和STAT1的磷酸化(P＜0.01).AG490治疗显著减轻肾小管损害[(21.7±1.7)%比(49.4±1.0)%]和肾间质纤维化(1.0±0.1比2.3±0.2)、α-SMA表达(0.9±0.1比2.1±0.2)和巨噬细胞积聚[(13.3±1.6)细胞/HPF比(34.4±1.0)细胞/HPF](均P＜0.01).AG490治疗显著抑制Ⅲ型胶原和MCP-1 mRNA表达.结论 JAK-STAT信号通路在肾小管间质炎性反应和纤维化中发挥重要作用.     

Effect of thymosin β4 on transforming growth factor-β/connective tissue growth factor of renal tubular interstitial fibrosis rats

Objective To investigate the influence of thymosin beta 4 (Tβ4) with two different dosages on the expression of transforming growth factor beta (TGF-β) and connective tissue growth factor (CTGF) in rats with renal tubular interstitial fibrosis, and to further estimate the changes of renal tubular interstitial lesions. Methods Rat models of renal tubular interstitial fibrosis were established by unilateral ureteral occlusion (UUO). The male SD rats were randomly divided into 4 groups and 15 rats in each group: sham group, model group, treatment group with 1 mg/L Tβ4 and treatment group with 5 mg/L Tβ4. Rats in sham group and model group were poured into the same amount of saline. The renal function and renal pathological changes were observed after the second week. The mRNA and protein expression of TGF-β and CTGF in renal tissues was tested by in-situ hybridization and Western blotting. Results Compared with that in sham group, the expression of TGF-β mRNA and its protein, CTGF mRNA and its protein was significantly higher in model group (all P＜0.01). Compared with rats of model group, Tβ4 treatment rats had lower mRNA and protein expression of TGF-β and CTGF (all P＜0.01), and the expression in treatment group with 5 mg/L Tβ4 was lower than that in treatment group with 1 mg/L Tβ4 (P＜0.05). And the expression of TGF-β mRNA was positively correlated with CTGF mRNA expression (r=0.697, P＜0.01). The 24 h total urinary protein and the area of renal tubular interstitial lesion in model group were significantly more than those in sham group, and also more than those in Tβ4 treatment group (all P＜0.05). Tβ4 treatment attenuated kidney damage, and the effects in treatment group with 5 mg/L Tβ4 were better than those in treatment group with 1 mg/L Tβ4. No difference in serum creatinine and blood urea nitrogen was observed among 4 groups (all P＞0.05). Conclusions Tβ4 treatment can inhibit the renal TGF-β and CTGF expression of rats with tubular interstitial fibrosis in a dose-dependent manner, and play a protective role in kidney.