Loss of angiotensin-converting enzyme 2 enhances TGF-β/Smad-mediated renal fibrosis and NF-κB-driven renal inflammation in a mouse model of obstructive nephropathy

It is known that angiotensin (Ang)-converting enzyme (ACE) 2 catalyzes Ang II to Ang 1-7 to prevent the detrimental effect of Ang II on blood pressure, renal fibrosis, and inflammation. However, mechanisms of renoprotective role of Ace2 remain largely unclear. The present study tested the hypothesis that deficiency of Ace2 may accelerate intrarenal Ang II-mediated fibrosis and inflammation independent of blood pressure in a model of unilateral ureteral obstructive (UUO) nephropathy induced in Ace2(+/y) and Ace2(-/y) mice. Results showed that both Ace2(+/y) and Ace2(-/y) mice had normal levels of blood pressure and plasma Ang II/Ang 1-7. In contrast, deletion of ACE2 resulted in a fourfold increase in the ratio of intrarenal Ang II/Ang 1-7 in the UUO nephropathy. These changes were associated with the development of more intensive tubulointerstitial fibrosis (α-SMA, collagen I) and inflammation (TNF-α, IL-1β, MCP-1, F4/80(+) cells, and CD3(+)T cells) in Ace2(-/y) mice at day 3 (all P<0.05) after UUO, becoming more profound at day 7 (all P<0.01). Enhanced renal fibrosis and inflammation in the UUO kidney of Ace2(-/y) mice were largely attributed to a marked increase in the intrarenal Ang II signaling (AT1-ERK1/2 mitogen-activated protein kinase), TGF-β/Smad2/3, and NF-κB signaling pathways. Further studies revealed that enhanced TGF-β/Smad and NF-κB signaling in the UUO kidney of Ace2(-/y) mice was associated with upregulation of an E3 ligase Smurf2 and a loss of renal Smad7. In conclusion, enhanced Ang II-mediated TGF-β/Smad and NF-κB signaling may be the mechanisms by which loss of Ace2 enhances renal fibrosis and inflammation. Smad7 ubiquitin degradation mediated by Smurf2 may be a central mechanism by which Ace2(-/y) mice promote TGF-β/Smad2/3-mediated renal fibrosis and NF-κB-driven renal inflammation in a mouse model of UUO nephropathy.     

C-reactive protein promotes acute renal inflammation and fibrosis in unilateral ureteral obstructive nephropathy in mice

Elevated blood level of C-reactive protein (CRP) is associated with increased risk of chronic kidney disease. However, whether this association reflects functional importance of CRP in the pathogenesis of kidney disease remains unclear. In this study, we examined the biological role of CRP in a well-characterized model of progressive kidney disease, unilateral ureteral obstruction (UUO), in mice that express the human CRP gene (CRPtg). Compared with wild-type (Wt) mice at 3 days after UUO, CRPtg mice developed more severe renal inflammation with a significant increase in tubulointerstitial T cells and macrophages, upregulation of proinflammatory cytokines (IL-1β and TNF-α), chemokines (MCP-1), and adhesion molecules (ICAM-1). Renal fibrosis was also significantly enhanced in CRPtg mice as demonstrated by increased expression of tubulointerstitial α-smooth muscle actin and collagen types I and III compared with Wt mice. Interestingly, on days 7 and 14 after UUO, an equal severity of renal inflammation and fibrosis were observed in CRPtg and Wt mice. These findings suggested that CRP may have a role in the initiation of renal inflammation and fibrosis. Further study revealed that enhanced early renal inflammation and fibrosis on day 3 in CRPtg mice was associated with a significant upregulation of endogenous mouse CRP and FcγRI mRNA and increased activation of both NF-κB/p65 and TGF-β/Smad2/3 signaling, while equal severity of progressive renal injury at day 7 and day 14 between CRPtg and Wt mice were attributed to equivalent levels of CRP, FcγRI, phospho-NF-κB/p65, and TGF-β/Smad2/3 signaling. Based on these findings, we conclude that CRP may not only be a biomarker, but also a mediator in the early development of renal inflammation and fibrosis in a mouse model of UUO. Enhanced activation of both NF-κB and TGF-β/Smad signaling pathways may be mechanisms by which CRP promotes early renal inflammation and fibrosis.     

Diverse roles of TGF-β receptor II in renal fibrosis and inflammation in vivo and in vitro

TGF-β1 binds receptor II (TβRII) to exert its biological activities but its functional importance in kidney diseases remains largely unclear. In the present study, we hypothesized that TβRII may function to initiate the downstream TGF-β signalling and determine the diverse role of TGF-β1 in kidney injury. The hypothesis was examined in a model of unilateral ureteral obstructive (UUO) nephropathy and in kidney fibroblasts and tubular epithelial cells in which the TβRII was deleted conditionally. We found that disruption of TβRII inhibited severe tubulointerstitial fibrosis in the UUO kidney, which was associated with the impairment of TGF-β/Smad3 signalling, but not with the ERK/p38 MAP kinase pathway. In contrast, deletion of TβRII enhanced NF-κB signalling and renal inflammation including up-regulation of Il-1β and Tnfα in the UUO kidney. Similarly, in vitro disruption of TβRII from kidney fibroblasts or tubular epithelial cells inhibited TGF-β1-induced Smad signalling and fibrosis but impaired the anti-inflammatory effect of TGF-β1 on IL-1β-stimulated NF-κB activation and pro-inflammatory cytokine expression. In conclusion, TβRII plays an important but diverse role in regulating renal fibrosis and inflammation. Impaired TGF-β/Smad3, but not the non-canonical TGF-β signalling pathway, may be a key mechanism by which disruption of TβRII protects against renal fibrosis. In addition, deletion of TβRII also enhances NF-κB signalling along with up-regulation of renal pro-inflammatory cytokines, which may be associated with the impairment of anti-inflammatory properties of TGF-β1.     

结缔组织生长因子在单侧输尿管梗阻大鼠肾组织中的表达

目的：检测大鼠单侧输尿管梗阻（UUO）模型不同时期，肾组织中结缔组织生长因子（CTGF）、转化生长因子β1（TGF-β1）和α-平滑肌肌动蛋白（α-SMA）的表达，观察比较在间质纤维化不同阶段，3者的动态变化及关系。 方法： 采用雄性SD大鼠36只，分为假手术组和模型组，模型组行左侧输尿管结扎术，再分3、7、14、21和28 d共6组，每组6只，于各时点处死大鼠，取肾组织，常规HE、Masson染色，按小管间质损害的特征进行半定量评分。免疫组化检测CTGF、TGF-β1和α-SMA表达。 结果： 随梗阻时间的延长，小管间质纤维化加重，28 d间质已基本被纤维化组织所代替。随间质纤维化程度的加重，CTGF和α-SMA表达逐渐增加，两者与小管间质损害积分呈正相关，CTGF与α-SMA的表达之间也呈正相关。TGF-β1表达在7-14 d达高峰后，逐渐减少，但仍高于对照组。 结论： UUO致CTGF表达增加可能与TGF-β升高有关，CTGF可能通过促进间质中肌成纤维细胞的形成而参与肾间质纤维化。     

IL-17在肾间质纤维化中的作用初探

探讨白细胞介素17(IL-17)在肾间质纤维化发生发展中的作用。采用的体内实验为,以单侧输尿管梗阻(unilateral ureteric obstruction,UUO)启动纤维化病理过程。将C57BL/6小鼠分为假手术组(Sham)和单侧输尿管梗阻(unilateral ureteric obstruction,UUO)组,分别于术后第1、3、7天处死,留取手术侧肾组织。采用HE、PAS、PASM、Masson染色评价肾间质组织病理变化。以免疫组化、实时荧光定量PCR(qRT-PCR)法检测α平滑肌肌动蛋白(α-SMA)表达水平;酶联免疫吸附试验(ELISA)检测IL-17在肾组织中的表达情况。体外实验为,分离培养C57BL/6小鼠肾成纤维细胞,转化生长因子β1(TGF-β1)刺激使其转化为肌成纤维细胞,继而用蛋白免疫印迹法(western blotting)检测IL-17的刺激下α-SMA表达水平。结果显示,组织病理学检查显示随着梗阻时间延长,炎性细胞浸润明显,肾小管萎缩,间质面积增大,Ⅰ型胶原和α-SMA增多。PCR检测显示α-SMA mRNA表达增多。但ELISA结果显示肾组织中IL-17含量呈下降趋势。Western blot结果表明肌成纤维细胞在IL-17的刺激下,α-SMA蛋白水平显著下降。实验说明,单侧输尿管梗阻手术可导致相应侧肾组织发生纤维化病变,但肾组织中IL-17含量与纤维化病变并不一致,在体外实验中IL-17可下调肌成纤维细胞表达的α-SMA。     

IKKα aggravates renal fibrogenesis by positively regulating the Wnt/β-catenin pathway

AKI (acute kidney injury) with maladaptive repair plays exacerbated role in renal fibrosis characterized by tubulointerstitial fibrosis. Previously, we reported that IKKα contributed to kidney regeneration and inhibited inflammation. Here, we first identified the role and mechanism of IKKα on TGF-β1-induced fibrosis in human tubular epithelial cells and fibrotic kidneys. IKKα was up-regulated in kidney tubular epithelium in unilateral ureteral obstruction (UUO) and unilateral ischemic reperfusion injury (UIRI) mice. Immunohistochemical staining showed that IKKα was positively correlated with the extent of kidney fibrosis in tissue biopsies from chronic kidney disease (CKD) patients. Compared with wild-type controls, Ksp-IKKα^−/− mice exhibited inactivated Wnt/β-catenin pathway, decreased serum creatinine and interstitial fibrosis in the kidney after IRI. In TGF-β1-stimulated human tubular epithelial cells, IKKα overexpression enhanced β-catenin nuclear translocation. Blocking IKKα by siRNA specifically suppressed β-catenin activation and downstream profibrotic genes such as fibronectin and α-smooth muscle actin (α-SMA). Taken together, our study demonstrated that IKKα aggravated renal fibrogenesis by activating Wnt/β-catenin signalling pathway, providing a new target for the treatment of kidney fibrosis.     

Smad2/3信号蛋白在大鼠梗阻性肾病肾组织中的表达

目的:探讨Smad2/3信号蛋白在大鼠梗阻性肾病模型肾组织中的表达及可能作用。 方法:采用单侧输尿管结扎（UUO）模型，分别于造模后1、3、7、14、21和28 d取肾组织，用免疫组化法检测TGFβ₁、磷酸化Smad2/3和α-SMA在梗阻肾肾组织中的表达；用原位杂交方法检测梗阻肾组织TGFβ₁ mRNA的表达。结果:正常大鼠肾组织具有基础的TGFβ₁(4.32%±1.72%)和磷酸化Smad2/3［(19.31±5.37）个/mm2］的表达，α-SMA只表达于血管平滑肌，肾小管-间质无表达。UUO术后1 d，TGFβ1的表达无明显增加(5.15%±2.08% vs对照组，P>0.05)，第3 d明显增加(13.55%±6.33% vs 对照组，P<0.01)，第7 d达高峰(26.78%±8.77% vs 对照组，P<0.01)，此后表达减少；磷酸化Smad2/3的表达在UUO术后3 d明显增加［(67.95±13.87）个/mm2 vs 对照组，P<0.01］，并持续增加到第7 d［（150.61±27.34）个/mm² vs 对照组，P<0.01］，此后表达减少；而UUO术后3 d肾组织α-SMA表达亦明显升高（5.58％±1.23％ vs 对照组，P<0.01），7 d达到高峰（13.43％±3.32％ vs 对照组，P<0.01），14 d表达开始下调；UUO术后肾间质细胞外基质的沉积随着疾病的进展而进行性增加，第28 d达到最高峰。梗阻肾肾组织中TGFβ₁、磷酸化Smad2/3以及α-SMA的表达时相一致并呈明显正相关（r₁=0.932, P<0.01；r₂=0.946, P<0.01），并与肾间质区域细胞外基质的积聚密切相关。 结论:磷酸化Smad2/3信号蛋白在大鼠梗阻性肾病肾组织中的表达明显增高，可能在肾间质纤维化的过程中起重要作用。     

结缔组织生长因子在单侧输尿管梗阻大鼠肾脏中的表达及其意义

目的： 观察结缔组织生长因子（CTGF）在单侧输尿管梗阻（UUO）大鼠模型中的动态表达，探讨CTGF在肾小管间质纤维化中的作用机制。方法： 将48 只Wistar大鼠随机分为UUO组和假手术（SO）组，采用左输尿管结扎术复制UUO模型，于术后1、3、7、14 d分别处死2组大鼠取左肾。采用Masson染色评定肾小管间质损伤程度；逆转录-聚合酶链式反应(RT-PCR) 方法检测肾组织转化生长因子-β₁（TGF-β₁）、CTGF、Ⅰ型胶原（ColⅠ）和纤溶酶原激活物抑制物-1（PAI-1）mRNA表达；免疫组织化学方法测定TGF-β₁、CTGF、ColⅠ、PAI-1表达；Western blotting方法检测CTGF蛋白表达量的变化。结果: UUO术后1d，梗阻肾TGF-β₁ mRNA表达开始升高，第3-14d时升高更显著（P<0.01），CTGF、ColⅠ、PAI-1 mRNA水平随之逐渐升高。免疫组织化学染色发现，UUO大鼠肾小管和间质区域CTGF表达随病程进展逐渐增强；相关分析显示，UUO术后第7d，CTGF表达量与肾小管间质损伤指数、肾小管间质TGF-β₁、ColⅠ、PAI-1表达强度均呈正相关，相关系数（r）分别为0.62、0.85、0.78和0.76（均P<0.01）。Western blotting结果显示，CTGF蛋白水平在术后第3d开始上升，随病程进展更显著。结论: CTGF可通过促进细胞外基质产生和抑制细胞外基质降解双重途径诱导肾小管间质纤维化的发生和进展。     

黄芩苷通过调控TGF-β1/TAK-NF-κB通路对胰腺纤维化的防治作用

目的:观察黄芩苷对慢性胰腺炎(CP)小鼠胰腺组织转化生长因子β1(TGF-β1)/TGF-β活化激酶(TAK)-核因子κB(NF-κB)信号通路的影响,探讨黄芩苷防治胰腺纤维化的作用机制。方法:健康雄性昆明小鼠58只,随机分为空白对照组、CP模型组和黄芩苷治疗组。除空白对照组外,其余小鼠均给予腹腔注射20%L-精氨酸诱发CP,治疗组于造模后2周开始腹腔注射黄芩苷(100 mg/kg,每天1次)。造模后2周、4周和6周分别处死动物,下腔静脉采血,摘取小鼠胰腺组织,HE及Masson染色检测各组小鼠胰腺组织形态学改变及纤维化程度;ELISA检测血清TGF-β1的表达;免疫组织化学法观察胰腺组织纤维连接蛋白(FN)和NF-κB的表达;Western blot检测胰腺组织FN、转化生长因子βⅠ型受体(TGF-βRⅠ)、磷酸化TAK1(p-TAK1)及NF-κB蛋白的表达;real-time PCR检测胰腺组织基质金属蛋白酶1(MMP-1)及金属蛋白酶组织抑制物1(TIMP-1)的mRNA表达。结果:腹腔注射20%L-精氨酸2周、4周和6周后,HE及Masson染色显示胰腺组织有纤维沉积,FN表...     

Attenuation of renal fibrosis by proteasome inhibition in rat obstructive nephropathy: possible role of nuclear factor kappaB

We previously reported that pyrrolidine dithiocarbamate blocked nuclear factor-kappaB (NF-kappaB) activation and attenuated interstitial inflammation and tubulointerstitial fibrosis in the rat obstructive nephropathy. Since pyrrolidine dithiocarbamate is an anti-oxidant and possesses additional biological properties, present experiment was conducted to clarify further the role of NF-kappaB in the development of tubulointerstitial fibrosis in obstructed kidney using a proteasome inhibitor that blocks NF-kappaB through stabilizing IkappaB, an endogenous inhibitor of NF-kappaB. At 5 days following unilateral ureteral obstruction (UUO) in rats, obstructed kidney exhibited tubulointerstitial fibrosis that was associated with macrophage infiltration. UUO decreased renal cortical IkappaB protein contents with concomitant increases in NF-kappaB DNA-binding activity and gene expression of monocyte chemoattractant protein-1. Administration of PSI, N-benzyloxy-carbonyl-Ile-Glu (O-t-Bu)-Ala-leucinal, a proteasome inhibitor, (3 mg/kg/day, s.c., b.i.d) to UUO rats inhibited proteasome activity and attenuated the changes in IkappaB content, NF-kappaB activity and MCP-1 mRNA expression observed in UUO rats. PSI also decreased macrophage influx and attenuated the development of fibrosis. Furthermore, up-regulated gene expression of pro-fibrogenic molecules observed in the obstructed kidney was attenuated by PSI. These results further support the notion that NF-kappaB plays an important role in the development of renal fibrosis in the obstructive nephropathy.     

Ac-SDKP suppresses epithelial–mesenchymal transition in A549 cells via HSP27 signaling

The synthetic tetrapeptide N-acetyl-seryl-aspartyl-lysyl-proline (Ac-SDKP) has been shown to be a modulator of molecular aspects of the fibrosis pathway. This study reveals that Ac-SDKP exerts an anti-fibrotic effect on human type II alveolar epithelial cells (A549), which are a source of myofibroblasts once exposed to TGF-β1, by decreasing the expression of heat shock protein 27 (HSP27). We used A549 cells in vitro to detect morphological evidence of epithelial–mesenchymal transition (EMT) by phase-contrast microscopy. Immunocytochemical and western blot analysis determined the distributions of cytokeratin 8 (CK8), α-smooth muscle actin (α-SMA), and SNAI1. Confocal laser scanning microscopy revealed a colocalization of HSP27 and SNAI1 on TGF-β1-induced A549 cells. These results also demonstrated that A549 cells became spindle-like when exposed to TGF-β1. Coincident with these morphological changes, expression levels of CK8 and E-cad decreased, while those of vimentin and α-SMA increased. This process was accompanied by increases in levels of HSP27, SNAI1, and type I and type III collagen. In vitro transfection experiments demonstrated that the inhibition of HSP27 in cultured A549 cells could decrease the expression of SNAI1 and α-SMA while increasing the expression of E-cad. A noticeable reduction in collagen types I and III was also evident. Our results found that Ac-SDKP inhibited the transition of cultured A549 cells to myofibroblasts and attenuated collagen synthesis through modulating the expression of HSP27.     

不同预缺血时间对肾小管间质纤维化的影响

目的：在建立缺血所诱发的肾小管间质纤维化大鼠模型基础上，探讨不同预缺血时间对肾脏纤维化的影响。方法:双侧肾蒂夹闭40 min后恢复灌注，制作缺血再灌注损伤模型，8 d前用同样方法分别造成肾脏预缺血10 min、20 min和30 min。预缺血后1 d、4 d、8 d和第2次缺血后5 周收集血样和肾脏标本。Masson特殊染色法观察小管间质纤维化程度；Western blotting法测定α-平滑肌肌动蛋白(α-SMA)、TGF-β1和磷酸化Smad2蛋白表达；免疫组织化学法观察肾脏α-SMA 和TGF-β1的分布。结果:术后5周单纯缺血再灌注组（I/R）和10 min 缺血预处理组（I-10/I）出现了相似程度的小管间质纤维化病变；30 min缺血预处理组（I-30/I）的肾脏纤维化明显加重，并伴有肾脏重量的增加、肾功能的减退和α-SMA、TGF-β1、phospho-Smad2蛋白表达进一步上调；相反，20 min缺血预处理组（I-20/I）的肾脏纤维化显著减轻甚至消失，与假手术对照组（sham）相比上述蛋白的表达无显著差异。结论:长时间的肾脏缺血可以引起小管间质纤维化，提前进行缺血预处理影响此病理改变，其作用结果与预缺血的时间长短密切相关，时间适中的预缺血能保护肾脏免于纤维化结局，其保护机制有待进一步研究。另外，肌成纤维细胞增多（α-SMA阳性）和TGF-β1/Smad信号通路激活可能参与缺血性小管间质纤维化病变过程。     

慢性肾功能衰竭促进小鼠动静脉瘘内膜增生

目的观察慢性肾功能衰竭对小鼠动静脉内瘘术后血管内膜增生的影响及单核细胞趋化蛋白-1(MCP-1)在内膜增生中的作用。方法将24只C57小鼠分为对照组(n=12)与实验组(n=12),实验组行左肾全切及右肾上极动脉结扎,对照组行假手术,术后6周行左侧颈总动脉-颈外静脉端吻合建立动静脉瘘(AVF)模型,AVF术后3周取瘘口静脉端血管组织。观察各组小鼠AVF内膜组织的病理改变及小鼠血液尿素氮(BUN)水平与内膜增生程度的关系;免疫组化法、RT-PCR及Western blot检测各组静脉组织α平滑肌肌动蛋白(α-SMA)、Ki-67、NF-κB及MCP-1的蛋白及mRNA的表达。结果 1)实验组较对照组小鼠血BUN水平明显上升(P0.05),静脉端内膜增生更显著,管腔更狭窄(P0.05)。2)实验组血管增生内膜α-SMA表达明显增加,血管平滑肌细胞(VSMC)增殖显著,NF-κB及MCP-1表达明显上升(均P0.05)。3)MCP-1促进体外培养VSMC增殖。结论慢性肾功能衰竭可明显增高NF-κB及MCP-1表达,从而促进动静脉瘘内膜增生及VSMC增殖。     

糖尿病大鼠肾组织中miR-21和SnoN表达的变化

目的探讨糖尿病(DM)大鼠肾组织中微小核糖核酸-21(miR-21)和核转录共抑制因子(SnoN)在肾纤维化过程中的表达变化及其可能机制。方法用链脲佐菌素复制DM大鼠模型,并设对照组(NC),每组n=8。10周后处死大鼠,观察肾组织形态变化;免疫组织化学染色、Western blot及RT-q PCR检测miR-21、SnoN、转化生长因子-β1(TGF-β1)、Smad3、p-Smad3(Ser423/425)、E钙黏蛋白(E-cadherin)、α-平滑肌肌动蛋白(α-SMA)、纤维连接蛋白(FN)、胶原蛋白Ⅰ(collagenⅠ)和胶原蛋白Ⅲ(collagenⅢ)的表达。结果与对照组相比,DM组肾组织p-Smad3(Ser423/425)、TGF-β1和α-SMA蛋白表达增加(P0.05),SnoN、E-cadherin蛋白表达减少(P0.05),但SnoN mRNA和miR-21表达明显上调(P0.05),并伴有collagenⅠ、collagenⅢ和FN在间质沉积增多。结论 TGF-β1可能上调miR-21表达,抑制SnoN翻译水平的表达,促进DN的纤维化病变。     

Liver-type fatty acid-binding protein attenuates renal injury induced by unilateral ureteral obstruction

Liver-type fatty-acid-binding protein (L-FABP), which has high affinity for long-chain fatty acid oxidation products, may be an effective endogenous antioxidant. To examine the role of L-FABP in tubulointerstitial damage, we used a unilateral ureteral obstruction (UUO) model. We established human L-FABP (hL-FABP) gene transgenic (Tg) mice and compared the tubulointerstitial pathology of the Tg mice (n = 23) with that of the wild-type (WT) mice (n = 23). Mice were sacrificed on days 2, 4, 5, or 7 after UUO. Although mouse L-FABP was not expressed in WT mice, hL-FABP was expressed in the proximal tubules of the Tg mice with UUO (UUO-Tg) and in sham-operated Tg mice. The expression of renal hL-FABP was significantly increased in UUO-Tg compared with sham-operated Tg mice. The number of macrophages (F4/80) infiltrating the interstitium and the level of expression of MCP-1 and MCP-3 were significantly lower in UUO-Tg kidneys compared with UUO-WT kidneys. In UUO-Tg kidneys, the degree of the tubulointerstitial injury and the deposition of type I collagen were significantly lower than that of UUO-WT kidneys. On day 7, lipid peroxidation product accumulated in the UUO-WT kidneys but not in that of UUO-Tg kidneys. In conclusion, renal L-FABP may reduce the oxidative stress in the UUO model, ameliorating tubulointerstitial damage.     

罗格列酮对阿霉素肾病大鼠肾组织中PPARγ、TGF-β1表达的影响

目的：探讨阿霉素肾病大鼠肾组织中过氧化物酶体增殖物激活受体（PPARγ）、转化生长因子β₁（TGF-β₁）表达和罗格列酮对阿霉素肾病大鼠的肾脏保护作用及其可能机制。方法: 将大鼠随机分成3组，正常对照组（n=6）、阿霉素肾病组（n=7）、罗格列酮治疗组（n=7），12周后测大鼠尿蛋白、血浆白蛋白、血脂和血肌酐、尿素氮，用免疫组化检测肾组织NF-κB p65的核转位及ELISA（夹心法）检测肾组织NF-κB p65的活性，RT-PCR测肾皮质PPARγ mRNA及TGF-β₁ mRNA的表达及免疫印迹检测肾皮质PPARγ、TGF-β₁蛋白表达，并进行相关分析。 结果: 与阿霉素肾病组相比，罗格列酮治疗组大鼠24 h尿蛋白排泄减少，血清白蛋白升高，血甘油三酯和胆固醇下降,差异显著(P＜0.01),肾脏病理损害减轻；肾组织NF-κB p65活化和TGF-β₁ mRNA和蛋白的表达均明显受抑制，而肾皮质PPARγ mRNA和蛋白表达显著增强，差异显著（P＜0.01)；阿霉素肾病组和罗格列酮治疗组大鼠肾组织中NF-κBp65活性与PPARγ mRNA表达呈直线负相关（r=－0.8305, P＜0.01）；肾组织中PPARγ mRNA与TGF-β₁ mRNA表达呈直线负相关（r=－0.7938, P＜0.01 ）。结论:罗格列酮作用于阿霉素肾病大鼠后，可能通过上调PPARγ表达，部分抑制肾组织NF-κB p65活性，进而抑制肾组织中TGF-β₁ 表达，从而使系膜基质沉积减少，肾组织病变减轻。     

丹参酮ⅡA对压力负荷增加大鼠心肌纤维化的改善作用

目的:观察丹参酮ⅡA(TanⅡA)对压力负荷增加大鼠心肌纤维化的改善作用。方法:60只SD大鼠随机分为假手术组(Sham组,n=8)和手术组(n=52),手术组均行腹主动脉缩窄术制备压力负荷增加心肌纤维化模型,术后4周,存活的32只成模大鼠中8只留作模型组(Model组),余24只分为TanⅡA低剂量组(L-TanⅡA组,10mg/Kg/天)、TanⅡA高剂量组(H-TanⅡA组,20mg/Kg/天)及阳性对照药物卡托普利组(Captopril组,100mg/Kg/天),每组8例。给药4周后,检测5组大鼠心肌肥厚指数和心肌组织形态、心肌羟脯氨酸(HYP)含量、心肌组织Rho相关卷曲螺旋蛋白激酶1(ROCK1)、转化生长因子-β1(TGF-β1)和核转录因子-κBp65(NF-κBp65)蛋白含量。结果:与Sham组比较,Model组大鼠的心肌肥厚指数、心肌HYP含量及心肌组织中ROCK1、TGF-β1和NF-κBp65蛋白含量均显著升高(P均<0.01),组织病理学改变明显;与Model组比较,L-TanⅡA和H-TanⅡA组心肌肥厚指数、心肌HYP含量及心肌组织中ROCK1、TGF-β1和NF-κBp65蛋白含量均降低(P<0.05或P<0.01),组织病理学改变明显。结论:TanⅡA能改善压力负荷增加大鼠心肌纤维化,此作用可能与其抑制ROCK1表达,下调TGF-β1和NF-κBp65水平有关。