PKCβ抑制剂LY333531对大鼠糖尿病模型肾脏巨噬细胞浸润的影响

探讨PKCβ抑制剂LY3335 31对大鼠糖尿病模型肾组织巨噬细胞浸润的影响。建立STZ诱导的大鼠糖尿病模型 ,随机分对照组、模型组与LY3335 31给药组 ,每组 1 0只。 8周后检测 2 4h尿白蛋白排泄率 (AER )及肾组织PKC活性 ;PAS染色观察肾小球病理形态学指标 ;应用免疫组化方法检测肾组织ED 1及MCP 1、ICAM 1表达。结果 :(1 )模型组大鼠肾重、肾重/体重、AER及肾小球面积、肾小球容量、系膜区面积明显高于对照组 (P <0 0 5 ,P <0 0 1 ) ,LY3335 31给药组这些改变明显减轻 (P <0 0 5 ) ;(2 )LY3335 31给药组肾组织细胞膜、细胞浆PKC活性明显低于模型组 (P <0 0 5 ) ;(3)模型组肾小球ED 1阳性细胞数及MCP 1、ICAM 1表达明显高于对照组 ,LY3335 31给药组肾小球ED 1阳性细胞数及MCP 1、ICAM 1表达明显低于模型组 (P <0 0 5 )。表明LY3335 31对糖尿病大鼠肾脏有明显保护作用 ,其机制可能部分与抑制肾组织巨噬细胞浸润有关。     

依那普利对大鼠糖尿病模型肾内炎症的干预作用及可能机制

目的：探讨依那普利对大鼠糖尿病模型肾内炎症的干预作用及可能机制。 方法： 建立STZ诱导的单侧肾切除大鼠糖尿病模型，随机分：对照组、糖尿病组与依那普利给药组，每组 10只。8周末检测24 h尿白蛋白排泄率(AER)、肾组织与尿丙二醛(MDA)含量及肾组织超氧化物歧化酶(SOD)、过氧化氢酶(CAT)与谷胱甘肽过氧化物酶(GSH-PX)活性。应用PAS染色观察肾小球病理组织学指标；免疫组织化学方法检测肾组织ED-1(巨噬细胞表面标志)及单核细胞趋化蛋白-1(MCP-1) 与细胞间粘附分子-1 (ICAM-1)表达。 结果： 依那普利给药组大鼠肾重、肾重/体重、AER与肾小球面积、肾小球容积及系膜区面积明显低于模型组(P<0.05, P＜0.01)；模型组肾组织和尿MDA含量明显高于对照组（P＜0.01），肾组织超氧化物歧化酶（SOD）、过氧化氢酶（CAT）与谷胱甘肽过氧化物酶（GSH-PX）活性明显低于对照组(P＜0.05,P＜0.01)，依那普利可明显缓解这些变化（P＜0.05）；模型组肾小球ED-1阳性细胞数及 MCP-1、ICAM-1表达明显高于对照组(P＜0.01)，依那普利给药组肾小球巨噬细胞浸润及MCP-1表达明显低于模型组(P＜0.05)， ICAM-1表达无明显差异。 结论： 依那普利对糖尿病大鼠肾脏保护作用机制部分可能与抑制肾内炎症有关。     

单核细胞趋化蛋白-1与糖尿病肾病

单核细胞趋化蛋白-1(MCP-1)是一种特异性趋化因子，在糖尿病肾病 (diabetic nephropathy，DN)的发生发展中起重要作用。代谢性因素如高糖（HG）、糖基化白蛋白（glycated albumin， Gly-Alb）、氧化应激，蛋白激酶C(protein kinase C，PKC)等和血流动力学因素如肾素-血管紧张素系统（RAS）等均可上调肾小球内皮细胞、系膜细胞 (mesangial cell，MC)、小管上皮细胞（tubulus epithelial cells，TECs）中MCP-1基因和蛋白的表达，使单核/巨噬细胞在肾组织中聚集，通过多种机制引起肾脏损伤。     

Association of TGFβ1, TNFα, CCR2 and CCR5 gene polymorphisms in type-2 diabetes and renal insufficiency among Asian Indians

Background  

Cytokines play an important role in the development of diabetic chronic renal insufficiency (CRI). Transforming growth factor β1 (TGF β1) induces renal hypertrophy and fibrosis, and cytokines like tumor necrosis factor-alpha (TNFα), chemoattractant protein-1 (MCP-1), and regulated upon activation and normal T cell expressed and secreted (RANTES) mediate macrophage infiltration into kidney. Over expression of these chemokines leads to glomerulosclerosis and interstitial fibrosis. The effect of MCP-1 and RANTES on kidney is conferred by their receptors i.e., chemokine receptor (CCR)-2 and CCR-5 respectively. We tested association of nine single nucleotide polymorphisms (SNPs) from TGFβ1, TNFα, CCR2 and CCR5 genes among individuals with type-2 diabetes with and without renal insufficiency.     

霉酚酸酯对糖尿病大鼠肾小管-间质损伤的保护作用及机制

研究霉酚酸酯(MMF)对糖尿病大鼠肾小管-间质损伤的保护作用,并探讨其可能机制。应用链脲佐菌素诱导大鼠糖尿病模型,随机分三组:对照组、模型组与MMF给药组。8周后观察尿白蛋白排泄率(AER)、肾小管-间质病理形态学变化,应用免疫组化方法检测肾小管-间质骨桥蛋白(OPN)与α-平滑肌肌动蛋白(-αSMA)蛋白表达,Western印迹检测肾组织IL-1与TNF-α蛋白表达。结果表明,糖尿病大鼠AER与肾小管-间质损伤指数(TII)明显高于对照组(P<0.01),MMF给药组AER与TII明显低于模型组(P<0.05);免疫组化显示模型组肾小管-间质OPN与-αSMA表达阳性面积明显高于对照组(P<0.01),MMF给药组肾小管OPN与与-αSMA表达阳性面积明显低于模型组(P<0.01);Western印迹显示模型组肾组织IL-1与TNF-α表达较对照组分别增加2.8倍与3.8倍,MMF给药组IL-1与TNF-α表达分别下降73%与70%(P<0.01)。研究显示MMF对糖尿病肾小管-间质损伤有明显保护作用,其机制可能部分与抑制肾小管-间质OPN与-αSMA表达有关。     

Dual therapy of rosiglitazone/pioglitazone with glimepiride on diabetic nephropathy in experimentally induced type 2 diabetes rats

Diabetic nephropathy is a major cause of end-stage renal disease (ESRD) in the general population. It is estimated that diabetic nephropathy will eventually develop in about 40% of all patients with diabetes; therefore, prevention is critical for delaying the development and progression of diabetic kidney disease. Despite extensive efforts, medical advances are still not successful enough to prevent the progression of the disease. In the present study, we focused on the comparison of combination therapies and whether they offered additional renoprotection. Type 2 diabetes mellitus was induced by intraperitoneally administering streptozotocin (90 mg/kg) in neonatal rats and then these rats were treated with rosiglitazone (1.0 mg/kg) in combination with glimepiride (0.5 mg/kg) or with pioglitazone (2.5 mg/kg) in combination with glimepiride (0.5 mg/kg). Diabetic nephropathy markers were evaluated by biochemical and ELISA kits and renal structural changes were examined by light microscopy and transmission electron microscopy. Results show that the combination of pioglitazone with glimepiride is more effective in amelioration of diabetic nephropathy than rosiglitazone with glimepiride drug therapy due to glycemic control, suppressing albumin excretion rate, total protein excretion rate and augmented TNF-a signaling during the development of streptozotocin induced type 2 diabetic nephropathy.     

伊贝沙坦联合舒洛地特对糖尿病大鼠肾脏协同保护作用的研究

目的： 探讨伊贝沙坦联合舒洛地特对大鼠糖尿病肾脏协同保护作用及其机制。 方法：将雄性SD大鼠随机分为5组:正常对照组（C）、糖尿病模型组(D)、伊贝沙坦组(I)、舒洛地特组（S）及伊贝沙坦与舒洛地特联合给药组（I+S）,糖尿病大鼠模型用STZ诱导。 12周后观察尿白蛋白的排泄率(UAER),做肾组织病理检查,测定肾组织中MDA含量与SOD、CAT、GSH-PX的活性变化。RT-PCR法检测肾组织中ICAM-1 mRNA的表达。EMSA 检测NF-κB的活性。结果：各给药组均可抑制糖尿病大鼠UAER的增加及肾组织病理结构损害,联合组优于单独给药组。对肾组织MDA含量增加及抗氧化应激的SOD、CAT、GSH-PX活性降低的改善作用,联合组优于单给药组。各给药组均可抑制肾组织NF-κB活性,以联合组最明显;糖尿病大鼠肾组织ICAM-1 mRNA表达明显高于对照组,各给药组肾组织ICAM-1 mRNA表达明显低于模型组,其中以联合组最明显。 结论：伊贝沙坦与舒洛地特联合用药对糖尿病肾脏保护作用优于任一单种用药,其机制可能部分是通过对糖尿病肾组织氧化应激、NF-κB 活性及 ICAM-1 mRNA表达协同抑制而实现的。     

Renoprotective effects of valsartan and enalapril in STZ-induced diabetes in rats

Effects of the angiotensin II type 1 (AT1) receptor antagonist valsartan and the angiotensin-converting enzyme (ACE) inhibitor enalapril were studied in streptozotocine (STZ)-induced diabetes in rats on the basis of microalbuminuria (Ma) and renal morphology. Five groups of Wistar rats were used, one group was the non-diabetic control, one group consisted of untreated STZ-diabetics and 3 groups of STZ-diabetics were treated with either enalapril and/or valsartan for 30 days. Blood glucose (BG) and Ma levels, body and kidney weight and glomerular size were measured. Immunohistochemical staining with an anti-transforming growth factor-beta1 (TGF-beta1) antibody was performed as well. In STZ-diabetics, BG and Ma levels were significantly increased when compared with the non-diabetic group. Although Ma levels in the valsartan-treated group was found to be higher than those in the non-diabetics group after 15 days of treatment, in all treated diabetic groups Ma levels were significantly decreased as compared with STZ-diabetics at the end of the experiment. Thickening of the glomerular and tubular basement membranes, increased mesangial matrix and glomerular size were found in the untreated diabetic group. All these changes were less in the treated groups. A significant increase in TGF-beta1 immunoreactivity was found in glomeruli of untreated STZ-diabetics as compared with non-diabetics. Again, TGF-beta1 expression was decreased in the treated groups as compared with untreated STZ-diabetics. We conclude that valsartan and enalapril have renoprotective effects in diabetic nephropathy. A combined therapy has an advantage because lower dosages of these drugs can be used. Their beneficial effects are related to a blockade of the renin-angiotensin system (RAS) and a decrease in TGF-beta1 expression in glomeruli.     

骨调素和巨噬细胞集落刺激因子在糖尿病大鼠肾组织中的表达及霉酚酸酯的干预作用

目的： 研究骨调素(OPN)和巨噬细胞集落刺激因子（M-CSF)在糖尿病大鼠肾组织中的表达及免疫抑制剂霉酚酸酯（MMF）的干预作用，旨在探讨MMF对糖尿病肾病(DN)的保护作用及机制。方法: Wistar大鼠行右肾切除术2周后,随机分为右肾切除对照组(NC)、糖尿病组(DM)、霉酚酸酯治疗组(DM+MMF)。腹腔注射链脲佐菌素(STZ,65 mg/kg ) 诱发糖尿病模型,MMF15 mg·kg^-1·d^-1灌胃。检测各组8周末的左肾重/体重比值、24 h尿蛋白（Upro）、血糖(BG) 、血肌酐( Scr)，观察肾脏形态学变化，免疫组化检测肾组织中OPN、M-CSF及CD68表达，荧光实时定量PCR测定肾组织中OPN mRNA表达。结果: 与对照组相比，DM组大鼠血糖、Upro、肾重/体重比值均显著上升(P<0.01);肾间质纤维化面积扩大(P<0.01);肾组织内OPN、M-CSF、CD68表达及OPN mRNA的表达均显著上调(P<0.01)。MMF干预后，上述指标除血糖外均被明显抑制(P<0.05或P<0.01)。结论: MMF减少糖尿病大鼠肾组织中OPN、M-CSF、CD68及OPN mRNA的表达，降低蛋白尿，预防肾损伤。MMF明显抑制DN肾小管－间质损害，可能与其抑制巨噬细胞的趋化与增殖有关。     

Exendin-4 attenuates renal tubular injury by decreasing oxidative stress and inflammation in streptozotocin-induced diabetic mice

Abstract

In this study, we aimed to research the restorative effects of exendin-4, a GLP-1 analog, on renal tubular injury in streptozotocin-induced diabetes model. BALB/c male mice were divided into four groups: non-diabetic, non-diabetic?+?exendin-4 (3?μg/kg), diabetic and diabetic?+?exendin-4. In our diabetic model, we observed renal injury mainly in tubular area rather than glomeruli and exendin-4 decreased tubular injury with its glucose lowering effect. Besides, PCNA positive tubular cells, activities of LDH and Na⁺-K⁺-ATPase were also significantly declined by the administration of exendin-4. Furthermore, exendin-4 attenuated the levels of ROS, MDA, 8-OHdG, proinflammatory cytokines (TNF-α, IL-1β), chemokine MCP-1, ICAM-1, and fibrosis-related molecules (transforming growth factor β1 and fibronectin). In consistent with reducing tubular injury, macrophage infiltration and both MCP-1 and ICAM-1 production in tubular cells were decreased. These results indicate that exendin-4 may decrease renal tubular injury seen in the beginning of diabetic nephropathy by decreasing ROS production and inflammation.     

安体舒通联合西拉普利对糖尿病大鼠肾脏保护作用的研究

目的: 探讨安体舒通和西拉普利联合使用对糖尿病大鼠肾脏的保护机制。方法: Wistar 大鼠随机分为5组:对照组(N组);模型组(D组);安体舒通组(S组);西拉普利组(C组);联合给药组(S+C组)。采用链脲佐菌素(STZ)注射于单肾切除大鼠的腹腔中建立糖尿病肾脏损害大鼠模型。4周后观察大鼠的24 h尿微量白蛋白及血清肌酐清除率。免疫组化法检测肾切片中核因子-κB(NF-κB)及纤溶酶原激活物抑制剂-1(PAI-1)的表达。用逆转录聚合酶链式反应(RT-PCR)方法检测肾组织中血管紧张素Ⅱ-1型受体(AT-1R)的表达。结果: 各给药组均可抑制糖尿病大鼠24 h尿微量白蛋白的增加、血清肌酐清除率的降低及肾组织病理结构损害,联合组优于单独给药组。各给药组均可抑制肾组织NF-κB及PAI-1的表达,以联合组最明显。各给药组均可使AT-1R mRNA的表达减少,以联合组最明显。结论: 安体舒通与西拉普利联合用药对糖尿病肾脏保护作用优于单独用药,其部分机制可能是通过抑制NF-κB 及PAI-1的活化、减少AT-1R表达而实现的。     

氯沙坦钾对2型糖尿病肾病大鼠肾脏TGF-β1、CD68和MCP-1 表达的影响

目的: 探讨氯沙坦钾对2型糖尿病肾病大鼠转化生长因子β₁ (transforming growth factor beta 1, TGF-β₁)、CD68(巨噬细胞标记物)和单核细胞趋化蛋白-1(monocyte chemoattractant protein-1,MCP-1)表达的影响,进一步说明氯沙坦钾对2型糖尿病大鼠肾脏的保护作用。方法: 雄性SD大鼠30只,按随机数字表法分为正常对照组、模型组和治疗组,每组10只。15周后, 观测肾组织形态学、肾功能和24 h尿蛋白定量等指标的变化, 用免疫组化法检测肾脏TGF-β₁、CD68和MCP-1表达水平的变化。结果: (1)与正常对照组相比,模型组及治疗组大鼠体重均降低,血糖、甘油三酯、胆固醇及MCP-1、CD68、TGF-β₁的阳性细胞数升高,模型组24 h尿蛋白和肌酐升高;(2)与模型组相比,治疗组血肌酐、24 h尿蛋白、甘油三酯及MCP-1、CD68、TGF-β₁的阳性细胞数明显降低。结论: 在2型糖尿病肾病大鼠中氯沙坦钾可以通过减少肾组织MCP-1表达,阻止巨噬细胞的浸润,下调TGF-β₁表达,对糖尿病肾病病变起到保护作用。     

Contraction of tubulointerstitial fibrosis tissue in diabetic nephropathy,as demonstrated in an in vitro fibrosis model

Tubulointerstitial fibrosis in diabetic nephropathy (DN) was investigated using an in vitro tissue model of remodeling, to determine the pathogenic mechanism of fibrosis that leads to renal atrophy, i.e., renal failure. The remodeling model consisted of a renal fibroblast-populated collagen lattice (FPCL). The overexpression of transforming growth factor (TGF)-β1 in the diabetic kidney gave rise to FPCL contraction. FPCL relaxation was induced by the subsequent addition of cytochalasin D. The FPCL failed to contract when exposed to TGF-β1 plus Y27632, a Rho kinase inhibitor. TGF-β1 induced the phosphorylation of myosin light chains, and Y27632 blocked this activity. TGF-β1-induced FPCL contraction was suppressed by the addition of 2,3-butanedione monoxime, a myosin ATPase inhibitor. As shown in the video, the contraction rate of the projections of the cells in the FPCL was significantly greater in the TGF-β1 group than in the control group. Collectively, these results indicate that TGF-β1-induced FPCL contraction is attributable to actin–myosin interactions in the fibroblasts through the activation of Rho kinase, the phosphorylation of myosin light chains, and the subsequent activation of myosin ATPase. We propose that via these mechanisms, tubulointerstitial fibrosis generates tissue contraction that leads to renal atrophy and renal failure in DN.     

Monocyte chemoattractant protein 1, macrophage inflammatory protein 1 alpha, and RANTES recruit macrophages to the kidney in a mouse model of hemolytic-uremic syndrome

The macrophage has previously been implicated in contributing to the renal inflammation associated with hemolytic-uremic syndrome (HUS). However, there is currently no in vivo model detailing the contribution of the renal macrophage to the kidney disease associated with HUS. Therefore, renal macrophage recruitment and inhibition of infiltrating renal macrophages were evaluated in an established HUS mouse model. Macrophage recruitment to the kidney was evident by immunohistochemistry 2 h after administration of purified Stx2 and peaked at 48 h postinjection. Mice administered a combination of Stx2 and lipopolysaccharide (LPS) showed increased macrophage recruitment to the kidney compared to mice treated with Stx2 or LPS alone. Monocyte chemoattractants were induced in the kidney, including monocyte chemoattractant protein 1 (MCP-1/CCL2), macrophage inflammatory protein 1alpha (MIP-1alpha/CCL3), and RANTES (CCL5), in a pattern that was coincident with macrophage infiltration as indicated by immunohistochemistry, protein, and RNA analyses. MCP-1 was the most abundant chemokine, MIP-1alpha was the least abundant, and RANTES levels were intermediate. Mice treated with MCP-1, MIP-1alpha, and RANTES neutralizing antibodies had a significant decrease in Stx2 plus LPS-induced macrophage accumulation in the kidney, indicating that these chemokines are required for macrophage recruitment. Furthermore, mice exposed to these three neutralizing antibodies had decreased fibrin deposition in their kidneys, implying that macrophages contribute to the renal damage associated with HUS.     

Effects of vitamin D on renal fibrosis in diabetic nephropathy model rats

This study is to investigate the effects of vitamin D on renal fibrosis in rat diabetic nephropathy models, as well as the changes and interactions in the expressions of renal fibrogenesis- and inflammation-related genes. Rat diabetic nephropathy models were established by high-fat diets, which were subjected to TGF-β1 manipulation, as well as vitamin D treatment. H&E staining, Masson staining, and TEM detection were performed to assess the effects of vitamin D treatment and/or TGF-β1 manipulation on pathological changes in the renal tissues in these rat diabetic nephropathy models. Immunohistology and real-time PCR were used to evaluate the expressions of TGF-β1, MCP-1, CTGF, and VDR. Histological staining and TEM detection showed that, in both TGF-β1 over-expressed and interfered groups, vitamin D administration alleviated the renal fibrosis, compared with the vehicle treatment. Similar results were observed with the immunohistological staining. Real-time PCR analysis indicated that, when TGF-β1 was over-expressed in diabetic nephropathy, the expressions of MCP-1 and CTGF were also up-regulated, which would be decreased by the treatment of vitamin D. On the other hand, when TGF-β1 was interfered in DN, the expressions of MCP-1 and CTGF were relatively down-regulated, which would be further lowered by vitamin D administration. The mRNA expression of VDR was elevated by vitamin D treatment in these diabetic nephropathy models. Active vitamin D₃ and lentivirus-mediated TGF-β1 interference could effectively reduce the renal fibrosis and protect the renal function in diabetic nephropathy rat models, which makes a promising therapeutic strategy for the disease.     

兔后肢缺血诱导的侧枝血管MCP-1的表达及其与巨噬细胞的关系

目的:检测单核细胞趋化蛋白-1(MCP-1)在侧枝血管生长过程中的表达及其与巨噬细胞浸润的关系。方法:单侧结扎兔股动脉并将股动脉远侧端吻合到伴行的股静脉上,7d后处死动物,用特异性抗MCP-1抗体和抗RAM11抗体(巨噬细胞标记物)结合共聚焦免疫荧光术,进行MCP-1和巨噬细胞的检测。结果:在正常血管MCP-1的表达非常弱,仅在中膜和外膜有微量表达,内皮细胞几乎不表达。在生长的侧枝血管MCP-1在血管各层都高水平表达,免疫荧光强阳性,是正常血管的7.8倍,和正常血管比较有显著差异性(P<0.05)。连续切片显示MCP-1的上调表达和巨噬细胞的浸润分布呈正相关。结论:在生长的侧枝血管MCP-1的表达显著上调,提示MCP-1在巨噬细胞的聚集和侧枝血管的生长过程中具有十分重要的作用。     

Coordinate Up-Regulation of the β-Chemokine Subfamily in Autoimmune Sialoadenitis of MRL/lpr Mice

Mononuclear cell (MNC) infiltration of the salivary and lacrimal glands is a major feature in Sjogren's syndrome (SS) and its animal model, murine autoimmune sialoadenitis (MAS). To investigate factors that influence selective infiltration by MNC of submandibular glands in young and adult MRL/lpr mice with MAS, expression of mRNA encoding the β-chemokines monocyte chemoattractant protein (MCP)-1, macrophage inflammatory protein (MIP)-1α, MIP-1β and regulated upon activation, normal T-cell expressed and secreted (RANTES) was investigated by in situ hybridization. MCP-1 protein production was also evaluated by immunohistochemistry. Young mice with MAS showed an early up-regulation of mRNA expression for MCP-1, MIP-1β and RANTES, while MIP-1α mRNA expression was not affected. Adult mice with MAS showed a further up-regulation of mRNA expression for MCP-1, MIP-1β and RANTES, and a remarkably strong up-regulation for MIP-1α. Immunohistochemistry revealed that MCP-1 protein production paralleled MCP-1 mRNA expression in both young and adult mice. These observations implicate MCP-1, MIP-1β and RANTES as potential chemokines in induction of MAS, and MCP-1, MIP-1β, RANTES and prominently MIP-1α in progression and perturbation of MAS.     

Renal injury induced in alloxan diabetic rats. Role of Mycophenolate Mofetil as therapeutic agent

BackgroundRenal injury may develop in uncontrolled chronic hyperglycemia due to increased oxidative stress and release of pro-inflammatory mediators, leading to diabetic complications.MethodsMycophenolate Mofetil (MMF) is an immunosuppressant drug, an inhibitor of inosine monophosphate dehydrogenase (IMPDH), relevant to inflammation processes. MMF effect was tested in alloxan-diabetic rats on selected parameters like oxidative stress, gene expression of tumor necrosis factor-α (TNF-α) and transforming growth factor-β1 (TGF-β1), in relation to microalbuminuria and renal function.ResultsWe found that the onset of microalbuminuria preceded the increase in serum glucose after alloxan treatment. Gene expression of TNF-α and TGF-β1 showed gradual increase after one and two weeks of alloxan administration as compared to the normal group. MMF administration decreased the gene expression of TNF-α and TGF-β1 in kidney tissues, serum glucose, fructosamine, urea, creatinine, C-reactive protein, malondialdehyde, urinary microalbumin and total protein. Histological examination of kidney tissues showed significant improvement in MMF treated rats as compared to diabetic control.ConclusionsMMF modulated renal injury of alloxan diabetic rats. Collective data may support its therapeutic effect but further clinical trials may be requested.     

左卡尼汀对糖尿病肾病大鼠的肾脏保护机制研究

目的:探讨左卡尼汀(L-carnitine,LC)对链脲佐菌素(streptozotocin,STZ)诱导的糖尿病肾病(diabetic nephropathy,DN)大鼠肾脏保护的分子机制。方法:对雄性Sprague-Dawley大鼠腹腔注射STZ(65 mg/kg)建立糖尿病模型,造模成功大鼠给予LC(50 mg·kg~(-1)·d~(-1)或200 mg·kg~(-1)·d~(-1))12周治疗,检测各组大鼠的肾功能、24 h尿蛋白排泄率和肾小球硬化程度;免疫组化和Western blot法分别检测炎性因子、致纤因子、核因子κB和细胞凋亡调控基因的表达。结果:LC治疗可明显减轻糖尿病大鼠肾小球硬化,保持足细胞数量,这些改变伴随着尿蛋白排泄率的减少和肾功能的改善。在分子水平上,LC可下调炎性介质和致纤因子的表达,调节细胞凋亡调控基因的表达,此作用可能与干预核因子κB信号通路有关。结论:LC对STZ诱导的DN大鼠具有抗炎、抗肾小球硬化的肾脏保护作用。     

Transforming growth factor-β stimulates IL-1β-induced monocyte chemoattractant protein-1 expression in human synovial cells via the ERK/AP-1 pathway

Objective and Design: Transforming growth factor- β (TGF-β) has not only a fibrogenic role, but also monocyte/ macrophage chemotactic properties in a synovial joint. However, little is known about the effects of TGF-β on monocyte chemoattractant protein-1 (MCP-1) expression in human synovial cells under inflammatory status. The aim of this study was to determine whether TGF-modulates MCP-1 production under the chronic inflammation, and to elucidate the cell signaling mechanism involved. Materials and methods: Human synovial cells were exposed to IL-1β, which mimics the environment of chronic inflammation. Production of MCP-1 protein and expression of MCP-1 mRNA were determined by ELISA and real-time PCR. Results: TGF-β upregulated the expression of MCP-1 mRNA and protein with or without IL-1β. TGF-β and IL-1β synergistically enhanced MCP-1 gene expression, and an AP-1 binding site was involved in the signal transduction. In addition, MEK inhibitor completely suppressed TGF-β-induced MCP-1 production. Conclusions: TGF-β and IL-1β synergistically enhance MCP-1 gene expression through the activation of the MEK/ERK1/2 pathways, which leads to AP-1 activation. The impairment of MCP-1 regulation by TGF-β in resident synovial cells might represent an important mechanism of chronic inflammation and tissue fibrosis in a synovial joint. MCP-1 should be considered a valid target for therapeutic intervention. Received 22 September 2005; returned for revision 3 February 2006; accepted by J. Skotnicki 29 May 2006