Triptolide attenuates renal interstitial fibrosis in rats with unilateral ureteral obstruction

Aim: Extracts of Tripterygium wilfordii Hook F. have been used to treat glomerulonephritis for more than 30 years in China. Most of the anti‐inflammatory and immunosuppressive activities of these extracts can be attributed to triptolide (Trip). The present study was to investigate the effect of Trip on renal interstitial fibrosis in a model of unilateral ureteral obstruction (UUO). Methods: UUO or sham‐operated rats were randomly assigned to receive mycophenolate mofetil (MMF), Trip or vehicle and were killed on days 7 and 14 after UUO or sham operation. Kidney specimens were fixed for immunohistochemistry for myofibroblasts (α‐smooth muscle actin, α‐SMA), macrophages (ED‐1), monocyte chemoattractant protein‐1 (MCP‐1) and osteopontin. Interstitial collagen deposition and amounts of transforming growth factor‐β1 (TGF‐β1) were determined by Sirius red staining and enzyme‐linked immunosorbent assay, respectively. The mRNA expression of TGF‐β1, connective tissue growth factor (CTGF), MCP‐1 and osteopontin were measured by real‐time polymerase chain reaction analysis. Results: The scores for the density of α‐SMA‐ and ED‐1‐positive cells, the staining of MCP‐1 and osteopontin, interstitial collagen deposition and amounts of TGF‐β1 were significantly reduced by MMF or Trip. MMF or Trip significantly reduced the mRNA expression of TGF‐β1, CTGF, MCP‐1 and osteopontin. Conclusion: Trip significantly attenuated tubulointerstitial fibrosis in a rat UUO model and the effect of Trip on renal fibrosis was similar to that of MMF. Trip may be useful as a potential candidate in the treatment of renal fibrosis.     

intermedin对单侧输尿管梗阻大鼠肾间质纤维化的影响

目的 观察intermedin( IMD)对单侧输尿管梗阻(UUO)大鼠肾间质纤维化的影响.方法 雄性Wistar大鼠40只,按随机数字表法分为假手术组(n=10,行左输尿管分离术)、模型组(UUO,n=10)、氯沙坦组(n=10)和IMD组(n=10),后3组行左输尿管结扎术.各组大鼠分别于术后第14、21天随机选取5只,腹主动脉采血并留取梗阻侧肾组织之后处死.HE、Masson染色观察肾组织病理变化;比色法测定血尿素氮(BUN)、血肌酐(Scr)及新鲜肾组织羟脯氨酸(Pro)含量;免疫组化方法检测肾组织中转化生长因子β1 (TGF-β1)、IMD的表达水平,并进行半定量分析.结果 与假手术组相比,不同时间点UUO组血BUN、Scr、肾组织Pro含量及TGF-β1、IMD的阳性表达均显著升高(P＜0.05);与UUO组相比,氯沙坦组血BUN、Scr、肾组织Pro含量及TGF-β1、IMD表达均降低(P＜0.05),IMD组除IMD表达增加外,其余均降低(P＜0.05).结论 IMD可减轻UUO肾间质纤维化,改善肾功能,其机制可能与拮抗纤维化炎性介质TGF-β1有关.     

姜黄素对单侧输尿管梗阻大鼠肾间质纤维化的影响

目的 探讨姜黄素对单侧输尿管梗阻(UUO)大鼠模型的影响及其可能机制.方法 将30只大鼠随机分为3组,每组10只:假手术组、模型组、姜黄素组.模型组和姜黄素组行右侧输尿管接扎术,假手术组只游离不接扎.术后第14天处死各组中的大鼠,股动脉取血,检测血清肌酐、尿素氮;留取梗阻侧肾脏,Maason染色观察肾间质纤维化程度,免疫组织化学方法测定TGF-β1、CTGF的表达情况,RT-PCR技术榆测肾组织TGF-β1 mRNA、CTGF mRNA表达.结果 姜黄素降低了BUN、Scr的含量,同时姜黄素显著减少了大鼠肾间质TGF-β1、CTGF的表达,并有效改善了肾脏的病理学损伤.结论 姜黄素对单侧输尿管梗阻大鼠有较明显的保护作用,这可能与其能减少大鼠肾间质TGF-β1、CTGF的表达有关.     

Effects of renal sympathetic denervation on renal interstitial fibrosis in rats with unilateral ureteral obstruction

Objective To observe the influence of renal sympathetic denervation (RSD) on renal interstitial fibrosis and transforming growth factor beta 1(TGF-β1) and microRNA-21 (miR-21) in rats with unilateral ureteral obstruction(UUO). Methods 40 male Wistar rats were randomly divided into UUO group (A group, n=10), sham UUO group (B group, n=10), RSD+UUO group (C group, n=10) and RSD+sham UUO group (D group, n=10). Rats in A group and C group underwent unilateral ureteral ligation, while those in B group and D group underwent sham operation. Rats in C group and D group were followed by RSD. Rats were sacrificed at 21 days after the operation to evaluate the fibrosis by Masson staining. Immunohistochemical staining and Western blotting were used to detect the expressions of collagen I (COL-I), collagen Ⅲ(COL-Ⅲ) and TGF-β1 in four groups. The expression of miR-21 was detected by fluorescence in situ hybridization (FISH) and quantitative real-time PCR (RT-qPCR). Results A large amount of collagen deposition was observed in the renal interstitial area in A and C group compared to either B or D group (P＜0.05), but the change in C group was decreased significantly than that in A group (P＜0.05). Similarly, the expressions of COL-I, COL-Ⅲ, TGF-β1 and miR-21 were obviously higher in A and C group compared to either B or D group (P＜0.05), but those change in C group were decreased significantly than those in A group (P＜0.05). The above indexes were not significantly different between B group and D group (P＞0.05). Conclusion RSD may relieve the renal interstitial fibrosis in UUO rats, and down-regulate the expression of TGF-β1 and miR-21.     

红细胞生成素对单侧输尿管梗阻大鼠肾间质纤维化的保护作用

肾间质纤维化是各种肾脏疾病进展到终末期肾病过程的共同途径.转化生长因子β1(TGF-β1)-Smads信号传导通路在肾间质纤维化的发生发展过程中起重要作用[1].     

Inhibition of Src kinase can ameliorate renal interstitial fibrosis in unilateral ureteral obstruction mice

Objective To investigate the effect and mechanism of Src kinase in renal interstitial fibrosis of unilateral ureteral obstruction (UUO) mice. Methods Male C57BL/6J mice were randomly divided into 4 groups, including sham operation group (n=8), sham operation+PP2 group (n=8), UUO operation group (n=8) and UUO operation+PP2 group (n=8). The mice were injected 2 mg/kg PP2 by intraperitoneal everyday after surgery in sham+PP2 group and UUO+PP2 group. PP2 dissolved in 1% DMSO (formulated with normal saline). Sham and UUO group were given equal 1% DMSO. The mice were sacrificed at 7th day. Renal collagen was observed with Sirius red stain. The activities of Src, protein kinase B (PKB, AKT), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK) and the protein expressions of α-smooth muscle actin (α-SMA) and fibronectin (FN) were detected by Western blotting. The expression of collagen I (COLⅠ) was detected by immunohistochemistry and the expressions of matrix metalloprotein 9 (MMP-9), tissue inhibitor of metalloproteinase 1 (TIMP-1), transforming growth factor-β1 (TGF-β1), monocyte chemotactic protein-1 (MCP-1), interleukin-6 (IL-6) were measured by ELISA. Results Compared with sham mice, UUO mice on 7th day displayed obvious renal fibrosis. Meanwhile, UUO mice had increased expressions of COLⅠ and FN, and activities of AKT, ERK and p38 MAPK (all P＜0.05). Their renal expressions of α-SMA, TGF-β1, MMP-9, TIMP-1, MCP-1 and IL-6 were also raised (all P＜0.05). Compared with those in UUO group, in UUO+PP2 group the activities of Src, AKT, p38 MAPK and ERK, and expressions of TGF-β1, MCP-1 and IL-6 decreased (all P＜0.05). Additionally, expressions of COLⅠ, FN and α-SMA, collagen deposition and renal fibrosis receded in UUO+PP2 group (all P＜0.05). However, the expressions of MMP-9 and TIMP-1 were not influenced by PP2 treatment. Conclusions Src kinase promotes myofibroblasts accumulation and inflammatory reaction through activating its downstream signaling pathway in the progressing of renal interstitial fibrosis.     

雌激素对单侧输尿管梗阻大鼠肾间质纤维化的保护作用

目的探讨雌激素对单侧输尿管梗阻（UUO）大鼠肾间质纤维化的作用。方法雌性SD大鼠30只，随机分为4组：Ⅰ组对照组；Ⅱ组生理雌激素组；Ⅲ组低雌激素组；Ⅳ组高雌激素组。UUO术后21d处死各组大鼠，光镜观察梗阻肾组织病理变化，并分别用免疫组化和RT-PCR方法检测各组肾组织α-平滑肌肌动蛋白（α-SMA）和金属蛋白酶1组织抑制剂（TIMP-1）的表达。结果低雌激素组间质纤维化病变最明显，高雌激素组病变显著减轻（P〈0．01）。与生理雌激素组相比，低雌激素组α—SMA和TIMP-1蛋白和基因的表达增加（P〈0．05）；高雌激素组上述物质表达则减少（P〈0．05）。结论雌激素可能通过抑制α-SMA和TIMP-1的表达进而减少细胞外基质的沉积而发挥肾保护作用。     

上调肾组织intermedin表达抑制单侧输尿管梗阻大鼠肾间质纤维化

目的观察上调肾组织intermedin(IMD)表达对单侧输尿管梗阻(UUO)大鼠肾间质纤维化的影响。 方法健康雄性Wistar大鼠随机分为假手术组、UUO组、IMD＋UUO组、空质粒＋UUO组。IMD＋UUO组和空质粒＋UUO组在输尿管结扎前分别将IMD-pcDNA3.1真核表达质粒和空质粒转入肾组织,real-time RT-PCR及免疫组化法检测转染效率。各组分别于术后7 d、14 d留取梗阻侧肾组织。HE、Masson染色观察肾组织病理变化;real-time RT-PCR检测肾组织中转化生长因子-β1(TGF-β1)、纤连蛋白(Fn1)的mRNA表达;Western印迹法检测Fn1的蛋白表达;免疫组化法检测TGF-β1的蛋白表达。 结果与假手术组相比,UUO组肾脏出现明显的病理改变,肾间质纤维化程度随梗阻时间延长加重(与假手术组比较,7 d, t＝11.927,P＝0.0003;14 d, t＝8.891,P＝0.0009);IMD＋UUO组肾脏病理改变及肾间质纤维化程度较同时间点UUO组明显减轻(7 d, t＝3.892,P＝0.018;14 d, t＝4.047,P＝0.016),而空质粒＋UUO组与UUO组无显著差别(7 d, t＝0.562,P＝0.604;14 d, t＝0.035,P＝0.974)。与同时间点假手术组相比,UUO组TGF-β1、Fn1的表达明显升高(TGF-β1 mRNA水平7 d, t＝4.432,P＝0.011;14 d, t＝4.873,P＝0.006;蛋白质水平7 d, t＝5.312,P＝0.006;14 d, t＝4.482,P＝0.011;Fn1 mRNA水平7 d, t＝6.053,P＝0.004;14 d, t＝7.345,P＝0.002;蛋白质水平7 d, t＝8.791,P＝0.009;14 d t＝8.027,P＝0.001);转染IMD质粒后Fn1的表达较同时间点UUO组明显下降(mRNA水平7 d, t＝3.103,P＝0.036;14 d, t＝2.913,P＝0.044;蛋白质水平7 d, t＝2.955,P＝0.042;14 d, t＝2.991,P＝0.040);而转染空质粒后Fn1的表达无明显变化(mRNA水平7 d, t＝0.095,P＝0.929;14 d, t＝0.158,P＝0.882;蛋白质水平7 d, t＝0.159,P＝0.881;14 d, t＝0.170,P＝0.874)。转染IMD和空质粒对TGF-β1的表达均无明显影响(转染IMD质粒mRNA水平7 d, t＝0.176,P＝0.869;14 d, t＝0.126,P＝0.906;蛋白质水平7 d, t＝0.198,P＝0.853;14 d, t＝0.196,P＝0.854;转染空质粒mRNA水平7 d, t＝0.100,P＝0.925;14 d, t＝0.097,P＝0.928;蛋白质水平7 d, t＝0.042,P＝0.968; 14 d, t＝0.060,P＝0.955)。 结论上调肾组织IMD的表达能明显减轻肾间质纤维化,但其作用不是通过直接抑制TGF-β1的表达实现的。     

Smad3 deficiency attenuates renal fibrosis, inflammation,and apoptosis after unilateral ureteral obstruction

BACKGROUND: Transforming growth factor-beta (TGF-beta) has been implicated in the development of renal fibrosis induced by unilateral ureteral obstruction (UUO). However, there is little information on signaling pathways mediating TGF-beta activity involved in molecular and cellular events leading to renal fibrosis induced by UUO. In this study, we sought to determine whether Smad3, a major signaling component of TGF-beta, mediated renal fibrosis induced by UUO. METHODS: Renal fibrosis, inflammation, and apoptosis induced by UUO were macroscopically and histologically compared between wild-type mice and Smad3 null mice. RESULTS: Gross appearance of the kidney after UUO showed relatively intact kidney in Smad3 null mice [Smad3(-/-) mice] when compared with that of wild-type mice [Smad3(+/+) mice]. Renal interstitial fibrosis based on the interstitial area stained with Aniline-blue or Sirius red solution was significantly attenuated in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Deposition of type I and type III collagens were also significantly reduced in the obstructed kidney of Smad3(-/-) mice. In addition, the numbers of myofibroblasts, macrophages, and CD4/CD8 T cells infiltrated into the kidney after UUO were significantly attenuated in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Furthermore, terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL) staining after UUO showed significantly reduced number of tubular apoptotic cells in the obstructed kidney of Smad3(-/-) mice when compared with that of Smad3(+/+) mice. Endogenous Smad pathway was activated in the obstructed kidney after UUO in wild-type mice as judged by the increase of phosphorylated Smad2 or phosphorylated Smad2/3-positive cells in renal interstitial area. CONCLUSION: Smad3 deficiency attenuated renal fibrosis, inflammation, and apoptosis after UUO, suggesting that Smad3 was a key molecule mediating TGF-beta activity leading to real fibrosis after UUO.     

内质网应激相关凋亡途径参与单侧输尿管梗阻大鼠肾间质纤维化

Objective To investigate the effect of endoplasmic reticulum stress (ERS)-associated apoptosis on renal interstitial fibrosis induced by unilateral ureteral obstruction (UUO) in rats. Methods Eighteen healthy male Wistar rats undergoing UUO were sacrificed at 3,7,14 days after operation. Additional seven rats underwent sham operation. Histological changes were observed by HE and Masson staining. Immunohistochemistry was performed on renal tissue for α-smooth muscle actin (α-SMA). Chromatometry was used to detect the content of hydroxyproline. Apoptosis cells were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and the electrophoresis analysis of genome DNA. The mRNA expression of glucose-regulated protein 78 (GRP78), which are important markers of ERS, were detected by RT-PCR. Western blotting was used to assess the protein level of GRP78 and cysteinyl aspartate specific proteinase-3 (caspase-3). Results Compared with sham operation group, the degree of renal interstitial and the level of hydroxyproline content of UUO group increased significantly (P<0.05). Immunohistochemistry staining indicated that a-SMA extensively expressed in renal tubular and interstitial cells. The apoptotic cells in the renal tubular and interstitium were continuously increased from day 3 to the end of experiment of UUO group. As early as 3 days after surgery, the mRNA level of GRP78 in UUO group increased compared with sham operation group (P<0.01), while the protein expression increased on day 7 after surgery (P<0.01). Prolonged ERS triggered apoptosis, the protein expression of caspase-3 increased significantly on day 3 after surgery (P< 0.05), and the expression sustained high level during the experiment afterwards. There was a positive correlation between GRP78 protein expression and hydroxyproline content (r =0.657, P< 0.01) as well as caspase-3 protein expression (r=0.714, P<0.01). Conclusions UUO induces a significant up-regulation in endoplasmic reticulum molecular chaperones at early stage, indicating that ERS response is activated in the rat kidney. Prolonged ERS can lead to renal tubular and interstitial cell apoptosis, and caspase-3-mediated ERS associated apoptosis may contribute to the fibrosis.     

细胞增殖与凋亡在单侧输尿管梗阻大鼠肾间质纤维化发病中的意义

目的 了解细胞增殖与凋亡在肾小管间质纤维化中的意义。方法 动态观察单侧输尿管梗阻（ＵＵＯ）大鼠模型中梗阻侧肾脏及假手术组肾脏肾小管细胞及间质细胞的增殖细胞核抗原（ＰＣＮＡ）表达及细胞凋亡情况,以及间质α平滑肌肌动蛋白（α－ＳＭＡ）表达水平。结果 ＵＵＯ大鼠梗阻肾从第３天至第１１天,均可见较大量的细胞凋亡,以肾小管上皮细胞居多,其中亦有间质细胞。无论肾小管或间质细胞,ＰＣＮＡ的表达在第３天已达高峰,     

内质网应激相关凋亡途径参与单侧输尿管梗阻大鼠肾间质纤维化

Objective To investigate the effect of endoplasmic reticulum stress (ERS)-associated apoptosis on renal interstitial fibrosis induced by unilateral ureteral obstruction (UUO) in rats. Methods Eighteen healthy male Wistar rats undergoing UUO were sacrificed at 3,7,14 days after operation. Additional seven rats underwent sham operation. Histological changes were observed by HE and Masson staining. Immunohistochemistry was performed on renal tissue for α-smooth muscle actin (α-SMA). Chromatometry was used to detect the content of hydroxyproline. Apoptosis cells were determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) and the electrophoresis analysis of genome DNA. The mRNA expression of glucose-regulated protein 78 (GRP78), which are important markers of ERS, were detected by RT-PCR. Western blotting was used to assess the protein level of GRP78 and cysteinyl aspartate specific proteinase-3 (caspase-3). Results Compared with sham operation group, the degree of renal interstitial and the level of hydroxyproline content of UUO group increased significantly (P<0.05). Immunohistochemistry staining indicated that a-SMA extensively expressed in renal tubular and interstitial cells. The apoptotic cells in the renal tubular and interstitium were continuously increased from day 3 to the end of experiment of UUO group. As early as 3 days after surgery, the mRNA level of GRP78 in UUO group increased compared with sham operation group (P<0.01), while the protein expression increased on day 7 after surgery (P<0.01). Prolonged ERS triggered apoptosis, the protein expression of caspase-3 increased significantly on day 3 after surgery (P< 0.05), and the expression sustained high level during the experiment afterwards. There was a positive correlation between GRP78 protein expression and hydroxyproline content (r =0.657, P< 0.01) as well as caspase-3 protein expression (r=0.714, P<0.01). Conclusions UUO induces a significant up-regulation in endoplasmic reticulum molecular chaperones at early stage, indicating that ERS response is activated in the rat kidney. Prolonged ERS can lead to renal tubular and interstitial cell apoptosis, and caspase-3-mediated ERS associated apoptosis may contribute to the fibrosis.     

内质网应激相关凋亡途径参与单侧输尿管梗阻大鼠肾间质纤维化

目的 探讨内质网应激（ERS）相关凋亡途径在单侧输尿管梗阻（UUO）大鼠肾间质纤维化发生、发展中的作用。 方法 健康雄性Wistar大鼠25只,按随机数字表法分为UUO模型组（n=18）和假手术组（n=7）,UUO模型组行左侧输尿管结扎术,假手术组仅分离输尿管不结扎,分别于术后3 d、7 d、14 d处死各组大鼠,行HE和Masson染色,观察肾脏病理变化;比色法测定肾组织羟脯氨酸（HYP）含量;免疫组化法检测α平滑肌肌动蛋白（α-SMA）;原位末端标记法（TUNEL）与DNA电泳观察肾小管间质细胞凋亡情况;RT-PCR法检测梗阻侧肾组织ERS相关分子葡萄糖调节蛋白78（GRP78）mRNA表达变化;Western印迹法分析凋亡相关蛋白半胱氨酸天门冬氨酸蛋白酶3（caspase-3）和GRP78的蛋白表达变化。 结果 与假手术组比较,UUO模型组肾脏病理改变加重,肾间质纤维化程度随梗阻时间延长逐渐加重,肾组织HYP含量显著升高（P < 0.05）,肾组织α-SMA也在肾小管间质细胞广泛表达,TUNEL染色及DNA琼脂糖凝胶电泳提示大量的肾小管间质细胞凋亡。UUO模型组GRP78 mRNA表达于术后3 d即发生显著上调,而蛋白表达在术后7 d开始出现显著变化,与假手术组差异均有统计学意义（均P < 0.01）;在此后观察期间内GRP78 mRNA和蛋白均持续高水平表达。模型组大鼠肾组织caspase-3的蛋白表达在UUO术后3 d即有显著上调（P < 0.05）,且随着梗阻时间延长进行性升高,于术后7 d、14 d增多更为显著,与假手术组差异均有统计学意义（P < 0.05）。相关分析显示GRP78蛋白表达与肾组织HYP含量和caspase-3蛋白表达均呈正相关（r = 0.657,P < 0.01;r = 0.714,P < 0.01）。 结论 UUO早期即可诱导ERS标志蛋白表达变化,触发ERS。长期ERS可诱导肾小管间质细胞凋亡;caspase-3介导的ERS相关凋亡途径可能参与了肾间质纤维化过程。     

COMP-angiopoietin-1 ameliorates renal fibrosis in a unilateral ureteral obstruction model

Injury to the renal microvasculature may be a major factor in the progression of renal disease; therefore, protection of endothelial cells (EC) in renal vasculature may have a therapeutic role in renal fibrosis. Recently, a soluble, stable, and potent angiopoietin-1 (Ang1) variant, cartilage oligomeric matrix protein (COMP)-Ang1, was developed. The contribution of COMP-Ang1 in renal interstitial fibrosis, however, remains to be clarified. This study investigated the effects of COMP-Ang1 on peritubular capillary EC in the renal cortex and the renal fibrogenic process that is triggered by unilateral ureteral obstruction. COMP-Ang1 preserved renal platelet-EC adhesion molecule-1-and Tie2-positive EC. Morphologic examination indicated less tubular injury and tubulointerstitial fibrosis in mice that received COMP-Ang1 than vehicle-treated mice. Interstitial type I collagen and myofibroblast accumulation were significantly suppressed by COMP-Ang1 treatment. COMP-Ang1 increased Tie2 and Akt phosphorylation in ureteral obstructed kidneys. Renal surface microvasculature and renal blood flow were higher after treatment with COMP-Ang1 than with vehicle. COMP-Ang1 treatment decreased monocyte/macrophage infiltration, tissue levels of TGF-beta1, and Smad 2/3 phosphorylation and increased Smad 7 in the obstructed kidney. These results demonstrate that COMP-Ang1 treatment can decrease the progression of renal fibrosis in unilateral ureteral obstruction. COMP-Ang1 may be an endothelium-specific therapeutic modality in fibrotic renal disease.     

Atorvastatin preserves renal function in chronic complete unilateral ureteral obstruction

PURPOSE: The pleiotropic effects of hMG-CoA (3-hydroxy-3-metylglutaryl coenzyme A) reductase inhibitors may provide renal protection in chronic kidney disease. We examined whether atorvastatin administration preserved renal function in rats with chronic unilateral ureteral obstruction. MATERIALS AND METHODS: Renal clearance experiments were performed in sham operated rats and rats subjected to 3 or 12-day unilateral ureteral obstruction. Hemodynamics parameters and urinary microalbumin levels from the obstructed kidney were also measured. The rats were maintained on a regular diet or the same diet but supplemented with atorvastatin (50 mg/kg daily). RESULTS: Atorvastatin administration did not alter plasma total cholesterol but it significantly decreased triglyceride levels. In sham operated and 3-day unilateral ureteral obstruction rats atorvastatin treatment did not have effects on the glomerular filtration rate or effective renal plasma flow and it also did not affect urinary microalbumin levels. In rats with 12-day unilateral ureteral obstruction the glomerular filtration rate but not effective renal plasma flow was significantly higher and urinary microalbumin was significantly lower in atorvastatin treated rats than in those without atorvastatin treatment. CONCLUSIONS: Atorvastatin treatment decreased microalbuminuria and helped preserve filtration function in chronic unilateral ureteral obstruction without altering plasma cholesterol levels, suggesting that pleiotropic renal protection is offered by this statin.     

Transforming growth factor-beta 1 antisense oligodeoxynucleotides block interstitial fibrosis in unilateral ureteral obstruction

BACKGROUND: Interstitial expression of transforming growth factor-beta1 (TGF-beta1) is important in tubulointerstitial fibrosis, a common process in most progressive renal diseases. However, no effective therapy for progressive interstitial fibrosis is known. Recently, we developed an artificial viral envelope (AVE)-type hemagglutinating virus of Japan (HVJ) liposome-mediated retrograde ureteral gene transfer method, which allowed us to introduce the genetic material selectively into renal interstitial fibroblasts. METHOD: We introduced antisense or scrambled oligodeoxynucleotides (ODNs) for TGF-beta 1 into interstitial fibroblasts in rats with unilateral ureteral obstruction, a model of interstitial fibrosis, to block interstitial fibrosis by retrograde ureteral injection of AVE-type HVJ liposomes. RESULTS: TGF-beta 1 and type I collagen mRNA increased markedly in the interstitium of untreated obstructed kidneys, and those were not affected by scrambled ODN transfection. Northern analysis and in situ hybridization revealed that the levels of TGF-beta 1 and type I collagen mRNA were dramatically decreased in antisense ODN-transfected obstructed kidneys. Consequently, the interstitial fibrotic area of the obstructed kidneys treated with antisense ODN was significantly less than that of the obstructed kidneys untreated or treated with scrambled ODN. CONCLUSION: The introduction of TGF-beta 1 antisense ODN into interstitial fibroblasts may be a potential therapeutic maneuver for interstitial fibrosis.     

Effect of macrophage polarization on interstitial fibrosis in mouse unilateral ureteral obstruction model

Objective To investigate the effect of macrophage polarization on tubulointerstitial fibrosis of mouse unilateral ureteral obstruction(UUO) model. Methods Twelve male C57BL/6J mice were employed, each of which with an age of 8 to 10 weeks. UUO model was established with these mice with the method of unilateral ureteral ligation. Mice were then sacrificed on the 7th and 14th day respectively after operation, and renal tissue specimens were obtained. The authors detected collagen deposition by Masson staining, and alpha smooth muscle actin (alpha SMA) as well as collagen type I (Coll-1) mRNA by real-time quantitative PCR. The authors also detected the degree of renal interstitial macrophages infiltration and expression changes of polarization by immunofluorescence staining. Results Compared with the mice that were observed on the 7th day after operation, the degree of renal interstitial fibrosis in mice observed on the 14th day after operation was comparatively serious, the difference shown by semi-quantitative results was statistically significant (P＜0.05). Moreover, mice observed on the 14th day after operation have more M2 macrophages, the difference between two groups of mice was statistically significant (P＜0.05). On the contrary, there was no statistically significant difference in the degree of M1 macrophages infiltration between these two groups of mice. Conclusions In the renal interstitial fibrosis model induced by UUO, the degree of macrophage infiltration increased significantly, mainly resulted from M2 macrophage infiltration, suggesting that M2 macrophages were involved in the formation of renal fibrosis.     

γ-干扰素对梗阻性积水肾间质纤维化的治疗作用

目的 探讨γ干扰素(IFN-γ)对梗阻性肾积水肾间质纤维化的抑制作用及其可能的机制.方法 将65只雄性SD大鼠随机分成4组:治疗组(20只)、模型组(20只)、药物对照组(20只)、假手术组(5只).在建模和给药后的第3、7、14、21、28天,每组各随机处死动物4只(假手术组1只).采用苏木素-伊红(HE)和Masson染色观察病变肾脏间质纤维化的情况;采用聚合酶链反应(RT-PCR)技术检测肾组织中转化生长因子-β1(TGF-β1)、α-平滑肌肌动蛋白(α-SMA)和Ⅰ型胶原(Col-Ⅰ)的mRNA表达情况;免疫组织化学法观察以上三种蛋白的变化.结果 模型组大鼠术后肾间质逐渐出现纤维化改变,并随梗阻时间的延长逐渐加重,TGF-β1、α-SMA和Col-Ⅰ的mRNA和蛋白表达亦逐渐升高.第14天,模型组TGF-β1和α-SMA的表达量达到高峰,28 d时各指标的表达均达到最高,TGF-β1、α-SMA和Col-Ⅰ分别为51.84%、72.59%和68.73%.治疗组各指标在不同时间点均低于模型组,第28天时,三项指标依次为33.84%、32.59%和48.73%,与模型组比较P＜0.05.Banff评分显示治疗组间质纤维化程度明显减轻(P＜0.01).其余两组未见肾间质纤维化改变.结论 IFN-γ具有减轻积水后肾间质纤维化程度的作用,该作用与其下调TGF-β1的表达、抑制肌成纤维细胞(MyoF)激活和减少Col-Ⅰ生成有关.