丹蛭降糖胶囊通过mTOR/S6K1信号通路对糖尿病肾病大鼠的干预作用研究

目的研究丹蛭降糖胶囊对糖尿病肾病大鼠的肾脏病理改变和足细胞自噬水平的影响,初步探讨其相应的作用机制。方法选取GK大鼠40只,采用醋酸脱氧皮质酮-盐皮下注射联合高脂饲料喂养诱导糖尿病肾病模型。造模成功后随机分为模型组、丹蛭降糖胶囊低剂量组[0.54 g/(kg·d)]、高剂量组[1.08 g/(kg·d)]、缬沙坦组[10 mg/(kg·d)],每组10只。另选取10只同周龄正常Wistar大鼠作为正常组。模型组和正常组给予等容积生理盐水。连续灌胃10周后检测空腹血糖(FBG)、血肌酐(SCr)、尿素氮(BUN)和尿微量蛋白(U-mAlb)。Western Blot检测肾小球p-mTOR、p-S6K1、Beclin-1、LC3和Nephrin蛋白的表达,HE染色和PAS染色后于光镜下观察肾脏病理变化,电镜下观察各组亚细胞形态结构变化。结果与正常组比较,模型组FBG、SCr、BUN、U-mAlb水平升高(P<0.01);与模型组比较,丹蛭降糖胶囊低、高剂量组和缬沙坦组U-mAlb水平降低(P<0.01)。模型组可见肾小球基底膜增厚,系膜基质沉积,足细胞损伤,各用药组均有不同程度改善,丹蛭降糖胶囊高剂量组足细胞内有较多自噬体形成。与正常组比较,模型组p-mTOR、p-S6K1的表达增高,Nephrin、Beclin-1和LC3的表达水平降低(P<0.01);与模型组比较,各用药组p-mTOR、p-S6K1的表达下降,Nephrin、Beclin-1和LC3的表达增高(P<0.01)。丹蛭降糖胶囊高剂量组和缬沙坦组Beclin1、LC3Ⅱ/LC3Ⅰ水平较丹蛭降糖胶囊低剂量组升高(P<0.05)。结论丹蛭降糖胶囊具有减轻糖尿病肾病大鼠U-mAIb、足细胞损伤及相关肾脏病理改变的作用,其机制可能与抑制mTOR/S6K1信号通路进而提高足细胞的自噬活性有关。     

加减下瘀血汤对低密度及氧化型低密度脂蛋白诱导小鼠肾足细胞血管内皮生长因子分泌的干预作用

目的：观察脂质低密度（LDL）及氧化型低密度脂蛋白（OX-LDL）对体外培养小鼠足细胞分泌血管内皮生长因子（VEGF）的影响及加减下瘀血汤的保护作用.方法：观察不同浓度下LDL和OX-LDL对小鼠肾足细胞分泌VEGF的影响,再用不同浓度加减下瘀血汤含药血清进行干预,分别用RT-PCR及ELISA检测足细胞分泌VEGF的变化.结果：LDL和OX-LDL可使肾足细胞分泌VEGF明显增高,且有浓度依赖性.中药加减下瘀血汤含药血清的干预可以明显抑制脂质诱导肾足细胞VEGF的高表达.结论：LDL和OX-LDL可以通过促进足细胞分泌VEGF增加而加重脂质肾毒性,而中药加减下瘀血汤可能通过抑制脂质诱导足细胞分泌过多VEGF,从而保护足细胞的脂质损伤.     

Kinetic study of glomerular epithelial cells associated with segmental glomerular sclerotic lesions with adhesion in spontaneously diabetic WBN/Kob rats

Background We previously found that glomerular epithelial cells play an important role in the formation of adhesive lesions. Glomerular sclerotic lesions develop after the inital adhesive lesions. Methods Two series of experiments were done with spontaneously diabetic WBN/Kob rats. These rats develop segmental glomerular sclerotic lesions with aging. The first series of experiments was intended to clarify the kinetics of glomerular cells on progressive glomerular damage in these rats. The second series of experiments was designed to study the relationship between proliferation (judged by % bromodeoxyuridine-positive cells) of glomerlar epithelial cells and sclerotic lesions with adhesions. Results In the first series, rats having increased proteinuria showed segmental glomerular sclerotic lesions with adhesions. At the same time, increased labeling indices of tuft cells and epithelial cells of Bowman's capsule were observed. In the second series, no significant increase in the labeling indices of tuft cells with sclerotic lesions was observed, compared to tuft cells without sclerotic lesions. In sclerotic lesions with adhesion, bromodeoxyurdine-positive cells were observed that were not distinguishable as podocytes or epithelial cells of Bowman's capsule. The highest labelling index was noted in the epithelial cells of Bowman's capsules with sclerosis. Conclusion This study shows that the proliferation of glomerular epithelial cells (mainly epithelial cells of Bowman's capsule) occurs in glomerular sclerotic lesions with adhesions.     

TrkC Is Essential for Nephron Function and Trans-Activates Igf1R Signaling

BackgroundInjury to kidney podocytes often results in chronic glomerular disease and consecutive nephron malfunction. For most glomerular diseases, targeted therapies are lacking. Thus, it is important to identify novel signaling pathways contributing to glomerular disease. Neurotrophic tyrosine kinase receptor 3 (TrkC) is expressed in podocytes and the protein transmits signals to the podocyte actin cytoskeleton.MethodsNephron-specific TrkC knockout (TrkC-KO) and nephron-specific TrkC-overexpressing (TrkC-OE) mice were generated to dissect the role of TrkC in nephron development and maintenance.ResultsBoth TrkC-KO and TrkC-OE mice exhibited enlarged glomeruli, mesangial proliferation, basement membrane thickening, albuminuria, podocyte loss, and aspects of FSGS during aging. Igf1 receptor (Igf1R)–associated gene expression was dysregulated in TrkC-KO mouse glomeruli. Phosphoproteins associated with insulin, erb-b2 receptor tyrosine kinase (Erbb), and Toll-like receptor signaling were enriched in lysates of podocytes treated with the TrkC ligand neurotrophin-3 (Nt-3). Activation of TrkC by Nt-3 resulted in phosphorylation of the Igf1R on activating tyrosine residues in podocytes. Igf1R phosphorylation was increased in TrkC-OE mouse kidneys while it was decreased in TrkC-KO kidneys. Furthermore, TrkC expression was elevated in glomerular tissue of patients with diabetic kidney disease compared with control glomerular tissue.ConclusionsOur results show that TrkC is essential for maintaining glomerular integrity. Furthermore, TrkC modulates Igf-related signaling in podocytes.     

Targeting tissue-resident memory CD8+ T cells in the kidney is a potential therapeutic strategy to ameliorate podocyte injury and glomerulosclerosis

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Corticosteroid treatment exacerbates nephrotic syndrome in a zebrafish model of magi2a knockout

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复方血栓通胶囊改善肾功能机制研究

[目的] 研究复方血栓通胶囊对糖尿病肾病(DN)大鼠24 h尿白蛋白、尿肌酐、血肌酐和血尿素氮等相关代谢指标的影响,及应用基因芯片探讨复方血栓通胶囊改善DN 大鼠肾功能的机制。[方法] 选用SD 大鼠45 只,高脂喂养/ 链尿佐菌素(STZ)注射法制备DN 模型,将DN 成模大鼠40 只随机分为小剂量、中剂量、大剂量血栓通组[ 分别给予0.3、0.6、1.2 g/(kg·d)的血栓通粉末悬浊液]、DN 模型组(给予生理盐水)。另外选用SD 大鼠10 只为正常对照组(给予生理盐水),均连续灌胃12 周。每月末测定大鼠空腹血糖(FBG)和体质量。3 个月末测定大鼠24 h尿白蛋白、尿肌酐、血肌酐和血清尿素氮水平。取大鼠肾脏组织进行Illumina基因芯片实验以期从整体基因角度揭示复方血栓通胶囊改善肾功能的机制。实时定量PCR 实验验证基因芯片的结果。[结果] 复方血栓通胶囊能以剂量依赖的方式降低24 h尿白蛋白、血肌酐和血清尿素氮,升高尿肌酐(P<0.05或P<0.01)。基因芯片显示大剂量血栓通组较模型组有67 个基因显著改变,其中34 个上调,33 个下调。实时定量PCR 实验发现大剂量血栓通组胶原蛋白1 型1(Col1a1)、结缔组织生长因子(Ctgf)和转化生长因子1(Tgfb1)基因较模型组显著下调,细胞色素P450 家族2 亚族C 肽23(Cyp2c23)和Nephrin-1(Nphs1)显著上调。[结论] 复方血栓通胶囊能有效改善DN 大鼠肾脏功能,其机制可能涉及Bmp2-Tgfβ-Ctgf通路,Cyp2c23 和足细胞损伤修复。     

儿童原发性肾病综合征肾组织CD2AP表达与足细胞损伤相关性的初步探讨

目的观察原发性肾病综合征(PNS)患儿肾组织CD2AP蛋白和mRNA的表达,探讨其与足细胞损伤的关系。方法以2012年1月至2013年6月上海市儿童医院收治的PNS且行肾活检的病例为PNS组,以同期我院行泌尿系统肿瘤切除患儿为对照组,取远离肿瘤并病理确认为正常肾组织。PNS组和对照组均行常规切片染色,光镜观察肾脏组织病理改变,电镜观察足细胞的结构变化,分别采用q PCR和免疫组化测定肾组织CD2AP mRNA和蛋白的表达。PNS组CD2AP mRNA表达与血清白蛋白(ALB)、SCr、三酰甘油(TG)、胆固醇(TC)、补体C3、24 h尿蛋白定量和肾小球滤过率(e GFR)行相关性分析。结果 PNS组18例、对照组11例进入分析,两组性别和年龄差异无统计学意义。1PNS组肾组织CD2AP蛋白的表达较对照组降低,(1.302±0.885)vs(2.24±1.18),P0.05,且病理表现为局灶节段性硬化(FSGS)的PNS患儿CD2AP蛋白表达最低。2PNS组肾组织CD2AP mRNA的表达较对照组下调,(0.008 58±0.006 12)vs(0.019±0.012),P0.05。3PNS组肾组织CD2AP mRNA表达与血清TG(r=-0.527,P0.05)、24 h尿蛋白定量(r=-0.602,P0.01)呈负相关,与肾组织CD2AP的蛋白表达呈正相关(r=0.788,P0.01),而与血清Alb、TC、补体C3、GFR和SCr无显著相关性。结论 PNS患儿肾小球足细胞中CD2AP的蛋白和mRNA表达降低,特别是病理表现为FSGS的患儿,可能对足细胞病变的诊断有一定帮助。CD2AP的表达量可能与PNS临床指标相关。