人工虫草对糖尿病大鼠足细胞上皮间质转分化影响的研究

目的 探讨人工虫草(金水宝)对糖尿病大鼠肾脏足细胞数目及转分化的影响.方法 利用链脲佐菌素诱导建立糖尿病大鼠模型,SD大鼠按随机数字表法分为3组:对照组、糖尿病模型组和人工虫草治疗组.干预8周后检测各组大鼠肾小球足细胞数目、nephrin、desmin及单核细胞趋化蛋白-1(MCP-1)水平.结果 与对照组比较,糖尿病模型组大鼠足细胞数目、nephrin水平明显下降(P＜0.05),desmin及MCP-1均明显升高(均P＜0.05).与糖尿病模型组相比,人工虫草治疗组足细胞数目、nephrin表达水平均明显增加,desmin和MCP-1的含量明显下降(均P＜0.05).结论 人[虫草对糖尿病大鼠足细胞转分化有明显的改善作用,并且能显著增加足细胞数目.     

肾缺血再灌注损伤大鼠模型足细胞损伤及机制研究

目的探讨肾缺血再灌注损伤(renal ischemia reperfusion injury,IRI)大鼠模型足细胞的损伤,并对其损伤机制进行初步研究。方法雄性SD大鼠42只,随机分为正常组(n=5)、假手术组(n=5)和模型组(n=32),模型组下设IRI后1h、6h、12h、24h4个时间点,每个时间点8只大鼠。通过阻断大鼠双侧肾脏血流构建肾IRI模型。采用全自动生化分析仪检测各组大鼠的肾功能,流式细胞仪检测血活性氧(reactive oxygen species,ROS)的变化,糖原染色(periodic Acid Schiff,PAS)了解肾脏病理损害,通过透射电镜观察足细胞损伤情况。结果在IRI大鼠模型中,我们发现了明显的足细胞损伤现象,即足细胞减少,足突消失,基底膜增厚。同时观察到,随着缺血再灌注后时间的延长,大鼠肌酐、尿素氮水平逐渐升高,红细胞中ROS荧光强度阳性率逐渐升高,肾小管出现不同程度的管腔扩张、变性与坏死,间质炎性细胞浸润、充血水肿等。相关性分析发现,红细胞ROS荧光强度阳性率与肾小管损伤评分、肌酐、尿素氮水平成正相关,与足细胞计数呈负相关。结论肾IRI早期足细胞就可出现明显的损伤,同时伴有血ROS荧光强度阳性率明显上升;血ROS的变化可能参与了肾IRI足细胞损伤及病理损害的过程。     

二维平面足细胞相对密度测量法

目的：探索一种简便且临床实用的足细胞丢失评估方法。方法：应用免疫组化法对正常和阿霉素肾病大鼠的肾组织,以及正常肾组织和3种不同病理类型肾小球疾病患者肾组织进行Wilms′瘤蛋白免疫染色,采用手工计数和病理图像分析技术相结合的方法分别对单个肾小球内足细胞的绝对数以及单位面积肾小球内足细胞的相对密度进行测定,找出结果可靠的最低肾小球数目并检验不同测量人员所获结果的一致性。结果：在统计10个和15个大鼠肾小球时,阿霉素肾病组肾小球足细胞相对密度显著低于正常大鼠;无论统计的肾小球数目多少,两组大鼠肾小球足细胞绝对数差异无统计学意义。在统计5个和10个人类肾小球时,局灶节段性肾小球硬化组和膜性肾病组肾小球足细胞相对密度均显著低于正常组和微小病变组;局灶节段性肾小球硬化组肾小球足细胞绝对数显著低于正常组和微小病变组。人类肾小球足细胞相对密度与血肌酐（Scr）水平呈低度负相关,但与24h尿蛋白含量（24hUPQ）无相关关系;阿霉素肾病大鼠肾小球足细胞相对密度与Scr、24hUPQ无相关关系。两名检测者所获结果有高度一致性。结论：这种足细胞相对密度评估法简便、快捷和可靠,且所需肾小球数目少,有望在临床实践中推广。     

表没食子儿茶素没食子酸醋对高糖环境下小鼠足细胞增殖和凋亡作用

目的 观察作为绿茶主要活性成分的表没食子儿茶素没食子酸醋(EGCG)对高糖环境下足细胞增殖和凋亡的作用并探讨其机制.方法 将足细胞分为9组.组1:正常糖(5.6 mmol/L).组2:正常糖(5.6 mmol/L)+0.1 mmol/L H2O2.组3:DMEM高糖(25 mmol/L).组4:20 μmol/L EGCG+DMEM高糖(25 mmol/L).组5:2.0 μmol/LEGCG+DMEM高糖(25 mmol/L).组6:0.2 μmol/LEGCG+DMEM高糖(25 mmol/L).组7:0.2 mmol/L维生素E+DMEM高糖(25 mmol/L).组8:0.1 μmol/L EGCG+0.1 mmol/L维生紊E+DMEM高糖(25 mmol/L).组9:24.4 mmol/L甘露醇+5.6 mmol/L葡萄糖.采用溴脱氧核苷尿嘧啶(BrdU)酶联免疫吸附试验(ELISA)检测细胞增殖,在Hoechst染色共聚焦激光显微镜下观察不同浓度EGCG作用24 h对足细胞凋亡的影响,采用Annexin V-FITC法检测足细胞凋亡,CM-H2DCFDA荧光探针检测足细胞内活性氧(ROS)生成.结果 ①足细胞增殖:与组1比较,组2在刺激24 h时的足细胞增殖的光密度(D)450值无显著变化(P＞0.05),48和72 h时D450值均显著降低(P值均＜0.05).与组2比较,组7和组8高糖刺激24 h时的D450值显著升高(P值均＜0.05),组4、组5和组6无显著变化(P值均＞0.05);组4、组7和组8在刺激48、72 h时的Dm值显著升高(P值均＜0.01).②激光共聚焦显微镜下,凋亡细胞表现为较多的核固缩,DNA浓缩并向核膜靠拢,核质比减小,以及胞膜皱缩等早期凋亡形态学变化.组2、组3的足细胞凋亡较组1增加,组7明显少于组4、组5,组9较组2无明显增加.③不同浓度EGCG作用后,组4、组5、组8的早期凋亡细胞膜联蛋白V(+)PI(-)比例和坏死细胞膜联蛋白V(+)PI(+)V(+)比例均显著低于组2(P值均＜0.05);组4、组8的早期凋亡细胞膜联蛋白V(+)PI(-)比例均显著低于组7(P值均＜0.05).④与组2比较,组4 24 h时的ROS显著减少(P＜0.05),但组6无显著改变(P＞0.05);与组7比较,组4 24 h时的ROS显著减少(P＜0.05),6、12 h时无显著变化(P值均＞0.05).结论 EGCG(20 μmol/L)作用72 h促进高糖环境下足细胞增殖,EGCG降低高糖刺激下小鼠足细胞凋亡的作用可能是通过减少足细胞ROS的生成实现的.     

Invagination and infolding of podocytes in glomerular basement membrane in the cases of primary membranous nephropathy

Background  The ultrastructural findings of membranous nephropathy (MN) are well described. Recently, podocyte infolding in the glomerular basement membrane (GBM) has been observed to be a unique ultrastructural finding formed from diffuse spherical microparticles and microtubules in the GBM. However, these alterations of glomerular epithelial cells have not been well characterized in MN. Methods  We selected 126 renal biopsies of primary MN that were diagnosed by light microscopy and immunofluorescence. In these biopsies, we investigated the ultrastructural alterations of GBM and podocytes, especially the presence of podocyte invagination, podocyte infolding, and spherical microparticles in the GBM. Results  In 98 cases (77.8%) we ultrastructurally detected occasional invagination of podocytes in the GBM within or around electron-dense or lucent deposits in mainly stage II–III of MN. In 40 cases (31.7%), we found spherical microparticles in addition to the podocyte invaginations in the GBM. In our cases, spherical microparticles were divided into three types; podocyte infolding, cell debris and virus-like particle types. Only one case displayed numerous spherical microparticles (microspheres) that were probably caused by infolding of podocytes. These microspheres, about 80 nm in diameter, were covered by unit membrane, and were accompanied by similar-sized microtubules and protrusions of podocytes. The spherical microparticles in the other cases were associated with cell debris (n = 23) or virus-like particles (n = 16) and were not connected with podocytes. Conclusion  Podocyte invagination associated with subepithelial deposits was a common pathological finding of primary MN, especially stage II–III of MN. The spherical microparticles in GBM in the case of MN may be associated with not only podocyte infolding but also cell debris and virus-like particles. The spherical microparticles in GBM due to diffuse podocyte infolding was considered as a new pathology finding of the GBM and may appear to be a new glomerular disease entity termed podocytic infolding glomerulopathy.     

A case report of glomerulopathy-associated podocytic infolding in a patient with tumor lysis syndrome

A 59-year-old man underwent total gastrectomy and splenectomy for gastric cancer 14 months before admission. The pathological diagnosis was neuroendocrine carcinoma of the stomach. Eight months after the operation, systemic chemotherapy with irinotecan and cisplatin was started because of multiple metastases to lymph nodes. After two courses of chemotherapy, renal function continued to decline. Renal biopsy showed acute tubular necrosis with cast formation, where needle crystallization was found. These clinicopathological findings suggested that tumor lysis syndrome was the cause of acute renal insufficiency. Moreover, diffuse, global bubbling and focal segmental spike formation were revealed by periodic acid-silver methenamine stain in the glomerular basement membrane. Electron microscopy showed an infolding of the cytoplasm of podocytes into the basal basement membrane and spotty electron-lucent areas. These ultrastructural findings, but not epimembranous deposits, corresponded with the bubbling on PAM staining. The present case was a rare case of glomerulopathy associated with podocytic infolding, which was not associated with collagen disease but with tumor lysis syndrome.     

A nephropathy presenting the microparticles in the glomerular basement membrane in a patient of hepatitis B viral infection

We report here unique electron microscopy findings showing clusters of deposition of spherical and tubular microparticles in a glomerular basement membrane (GBM) of a 46-year-old Japanese male with membranous nephropathy. Another distinct feature was the deep infolding of podocyte membranes into the GBM. Light microscopy showed the ladder formation of the GBM suggesting membranous nephropathy, while the immunofluorescent examination was atypical for the absence of the global capillary deposition of IgG and C3. He had mild liver dysfunction with positive hepatitis B antigen. Antibodies to hepatitis B surface antigen reacted weakly on the GBM in the immunohistochemistry. We suspected the unique findings of this case might be related to the hepatitis B viral infection.     

贝那普利对阿霉素肾病大鼠肾脏保护作用的研究

目的：观察贝那普利对阿霉素肾病大鼠形态学和肾皮质结蛋白表达改变的影响,探讨其对足细胞损伤的保护作用。方法：SD大鼠随机分为正常对照组、阿霉素肾病组和贝那普利治疗组。分别于给药4、7周后留取标本,检测24h蛋白尿、血肌酐,肾组织行形态学检查,应用免疫组化法检测肾皮质中结蛋白表达。结果：肾病组大鼠尿蛋白排泄明显高于对照组（P〈0．05）,且有明显的肾小球足细胞损伤的病理学改变。肾皮质结蛋白表达增加（P〈0．05）。贝那普利治疗后肾脏病理明显减轻,结蛋白表达降低（P〈0．05）。结论：在阿霉素肾病中,贝那普利可改善肾小球足细胞的损伤程度,降低结蛋白表达,对肾小球起保护作用。