Salvianolic acid A protects against vascular endothelial dysfunction in high-fat diet fed and streptozotocin-induced diabetic rats

Salvianolic acid A (SalA) is one of the main active ingredients of Salvia miltiorrhizae. The objective of this study was to evaluate the effect of SalA on the diabetic vascular endothelial dysfunction (VED). The rats were given a high-fat and high-sucrose diet for 1 month followed by intraperitoneal injection of streptozotocin (30 mg/kg). The diabetic rats were treated with SalA (1 mg/kg, 90% purity) orally for 10 weeks after modeling, and were given a high-fat diet. Contractile and relaxant responses of aorta rings as well as the serum indications were measured. Our results indicated that SalA treatment decreased the level of serum Von Willebrand factor and ameliorated acetylcholine-induced relaxation and KCl-induced contraction in aorta rings of the diabetic rats. SalA treatment also reduced the serum malondialdehyde, the content of aortic advanced glycation end products (AGEs), and the nitric oxide synthase (NOS) activity as well as the expression of endothelial NOS protein in the rat aorta. Exposure of EA.hy926 cells to AGEs decreased the cell viability and changed the cell morphology, whereas SalA had protective effect on AGEs-induced cellular vitality. Our data suggested that SalA could protect against vascular VED in diabetes, which might attribute to its suppressive effect on oxidative stress and AGEs-induced endothelial dysfunction.     

Salvianolic acid A protects against vascular endothelial dysfunction in high-fat diet fed and streptozotocin-induced diabetic rats

Salvianolic acid A (SalA) is one of the main active ingredients of Salvia miltiorrhizae. The objective of this study was to evaluate the effect of SalA on the diabetic vascular endothelial dysfunction (VED). The rats were given a high-fat and high-sucrose diet for 1 month followed by intraperitoneal injection of streptozotocin (30 mg/kg). The diabetic rats were treated with SalA (1 mg/kg, 90% purity) orally for 10 weeks after modeling, and were given a high-fat diet. Contractile and relaxant responses of aorta rings as well as the serum indications were measured. Our results indicated that SalA treatment decreased the level of serum Von Willebrand factor and ameliorated acetylcholine-induced relaxation and KCl-induced contraction in aorta rings of the diabetic rats. SalA treatment also reduced the serum malondialdehyde, the content of aortic advanced glycation end products (AGEs), and the nitric oxide synthase (NOS) activity as well as the expression of endothelial NOS protein in the rat aorta. Exposure of EA.hy926 cells to AGEs decreased the cell viability and changed the cell morphology, whereas SalA had protective effect on AGEs-induced cellular vitality. Our data suggested that SalA could protect against vascular VED in diabetes, which might attribute to its suppressive effect on oxidative stress and AGEs-induced endothelial dysfunction.     

氨基胍、牛蒡对糖尿病大鼠肾脏组织非酶糖化和细胞凋亡的影响

目的探讨非酶糖化与糖尿病肾病(DN)的关系,以及非酶糖化抑制剂氨基胍和具有非酶糖化抑制作用的牛蒡干预治疗对DN的治疗作用。方法雄性Wistar大鼠40只,随机分为4组,正常对照组、糖尿病组、糖尿病氨基胍(100mg·kg-1·d-1)治疗组(氨基胍组)、糖尿病牛蒡(150mg·kg-1·d-1)治疗组(牛蒡组),除正常对照组外,其他3组腹腔注射链脲佐菌素诱发糖尿病。16周后,处死大鼠,分离肾脏,测定组织非酶糖化,取部分肾脏皮质电镜观察细胞凋亡的形态学变化。结果治疗16周结束时,糖尿病各组大鼠体质量低于正常对照组(P<0.01),糖尿病各组间体质量比较差异无统计学意义(P>0.05);血糖水平均高于正常对照组(P<0.01);氨基胍组和牛蒡组血糖与治疗前比较,差异无统计学意义(P>0.05);糖尿病组大鼠肾组织肾皮质糖化终产物(AGEs)含量高于正常对照组(P<0.01),氨基胍组和牛蒡组AGEs含量低于糖尿病组(P<0.01),氨基胍组和牛蒡组比较差异无统计学意义(P>0.05)。透射电镜下见糖尿病组肾脏肾小管上皮细胞呈典型的凋亡形态学改变,氨基胍组和牛蒡组大鼠肾组织细胞凋亡改变明显减轻。糖尿病组肾小球基底膜增厚,系膜区域扩大。结论非酶糖化抑制剂氨基胍、牛蒡通过抑制非酶糖化、抑制细胞凋亡,明显改善糖尿病大鼠肾脏结构与功能,延缓DN的发展。     

Petroleum ether extract of Derris eriocarpa How.(PEEDEH) investigate antidiabetic nephropathy effect and mechanism through TLR4/NF-κB/caspase-3 pathways

OBJECTIVE To investigate anti-diabetic nephropathy effect and mechanism through Toll-like receptor 4(TLR4)/NF-κB/Caspase-3 pathway of petroleum ether extract of Derris eriocarpa How.(PEEDEH).METHODS Type 2 diabetes was induced in male Kunming(KM) mice through a combination of high-sugar and highfat diet for 2 months, after that, which was injected with streptozotocin(STZ, 80 mg·kg-1) via tail vein. After 3 d,mice with a fasting blood glucose(FBG)≥ 11.1 mmol·L~(-1) were considered diabetic. The mice were randomly assigned to normal control group, model group, metformin positive group(320 mg · kg~(-1)) and once that received low-, middle-, high-dose(200, 400, 800 mg · kg~(-1)) of PEEDEH for 21 days. RESULTS The intraperitoneal administration of PEEDEH reduced the levels of FBG,blood urine nitrogen(BUN), serum creatinine(Scr), kidney index, interleukin-6(IL-6) and tumor necrosis factor-α(TNF-α). Pathological changes of kidney observed by HE staining revealed that the pathology was improved. The expression of TLR-4, NF-κB, caspase-3 and COX-2 detected using immunohistochemical analysis indicated that their expressions were reduced after PEEDEH administration. PEEDEH also significantly reduced m RNA and protein expression levels of TLR-4/NF-κB/caspase-3 pathway in kidney compared to the diabetic group. CONCLUSION PEEDEH ameliorated DN through TLR-4/NF-κB/Caspase-3 signaling pathways.     

芝麻素与维生素E联用对代谢综合征

目的:观察芝麻素与维生素E联用对代谢综合征大鼠肾脏的保护作用并探讨两药联用的协同关系.方法:采用高脂高糖饮食24周诱导大鼠代谢综合征,第9周(57 d)口服含芝麻素(30 mg·kg~(-1)·d~(-1))、芝麻素+维生素E[(30+20)、(15+20)mg·kg~(-1)·d~(-1)]和维生素E(20mg·kg~(-1)·d~(-1))饲料16周.24周末称体重和左肾湿重;测血糖、血脂、血压、肾功能、肾皮质氧化和抗氧化指标;HE和Masson染色观察肾脏形态及胶原沉积;免疫组化法表达诱导型一氧化氮合酶和硝基酪氨酸.结果:(1)模型组肾功能明显损害,肾小球发生硬化和肾间质纤维化,并出现大量炎症细胞浸润,肾小球和肾间质胶原沉积,脂质过氧化物损伤因子MDA、NO_2~-/NO_3~-和OH~-含量升高,iNOS蛋白和硝基酪氨酸表达明显上调,抗氧化酶保护因子T-SOD、CAT、GSH-Px活性显著降低;(2)芝麻素+维生素E[(30+20mg/kg)]组能明显降低血糖、血脂和血压,提高肾皮质总超氧化物歧化酶、过氧化氢酶、谷胱甘肽过氧化酶活性,减少丙二醛、NO_2~-/NO_3~-和羟自由基含量,下调诱导型一氧化氮合酶和硝基酪氨酸,减轻肾小球与肾间质胶原沉积,逆转肾小球硬化和肾间质纤维化,改善肾功能,并且优于单用芝麻素组和维生素E组(P＜0.01或P＜0.05).结论:芝麻素(30 mg/kg)与维生素E(20 mg/kg)联用具有协同抗氧化和抗代谢综合征大鼠肾脏损伤作用.     

Effects of systemic inhibition of Rho kinase on blood pressure and renal haemodynamics in diabetic rats

BACKGROUND AND PURPOSE

The RhoA/Rho associated kinases (ROCK) pathway has been implicated in the pathophysiology of diabetic nephropathy (DN). Early stages of diabetes are associated with renal haemodynamic changes, contributing to later development of DN. However, the role of RhoA/ROCK, known regulators of vascular tone, in this process has not been studied.

EXPERIMENTAL APPROACH

Blood pressure (BP), glomerular filtration (GFR), effective renal plasma flow and filtration fraction (FF) in response to the ROCK inhibitors Y27632 (0.1 and 0.5 mg·kg⁻¹) and fasudil (0.3 and 1.5 mg·kg⁻¹) were examined in streptozotocin-diabetic rats and non-diabetic controls.

KEY RESULTS

Diabetic rats demonstrated baseline increases in GFR and FF. In contrast to similar decreases in BP in diabetic and control rats, renal vasodilator effects and a decrease in FF, following ROCK inhibition were observed only in diabetic rats. The vasodilator effects of Y27632 and a further decrease in FF, were also detected in diabetic rats pretreated with the angiotensin antagonist losartan. The effects of ROCK inhibitors in diabetic rats were modulated by prior protein kinase C (PKC)β inhibition with ruboxistaurin, which abolished their effects on FF. Consistent with the renal vasodilator effects, the ROCK inhibitors reduced phosphorylation of myosin light chain in diabetic kidneys.

CONCLUSIONS AND IMPLICATIONS

The results indicate greater dependence of renal haemodynamics on RhoA/ROCK and beneficial haemodynamic effects of ROCK inhibitors in diabetes, which were additive to the effects of losartan. In this process, the RhoA/ROCK pathway operated downstream of or interacted with, PKCβ in some segments of the renal vascular tree.     

Role of AGEs in diabetic nephropathy

Diabetic nephropathy is the most common cause of end-stage renal disease in the world, and accounts for a significant increase in morbidity and mortality in patients with diabetes. Therapeutic options such as strict blood pressure and/or glycemic control are effective for preventing the development and progression of diabetic nephropathy, but the number of diabetic patients on hemodialysis is still increasing. Therefore, a novel therapeutic strategy that could halt the progression of diabetic nephropathy should be developed. Advanced glycation end products (AGEs) are heterogeneous cross-linked sugar-derived proteins which could accumulate in glomerular basement membrane, mesangial cells, endothelial cells, and podocytes in patients with diabetes and/or end-stage renal failure. AGEs are thought to be involved in the pathogenesis of diabetic nephropathy via multifactorial mechanisms such as oxidative stress generation and overproduction of various growth factors and cytokines. Further, recently, the cross-talk between AGEs and the renin-angiotensin system (RAS) has been proposed to participate in diabetic nephropathy. In addition, activation of the RAS elicits ROS generation and subsequently stimulates growth factor and cytokine production by kidney cells as well. These observations suggest that combination therapy with inhibitors of the RAS and blockers of the AGEs formation and/or their downstream pathway may be a novel therapeutic option for preventing diabetic nephropathy. In this paper, we review the role of AGEs and their receptor system in the pathogenesis of diabetic nephropathy. We further discuss here the cross-talk between AGEs and the RAS in the development and progression of diabetic nephropathy.     

ROCK1 inhibitor fasudil improves diabetic wound healing via AMPK/Drp1/eNOS pathway

OBJECTIVE Refractory wounds in diabetic patients constitute a serious complication that often leads to amputation and has limited treatment regimens.As the first approved Rho-associated protein kinase 1(ROCK1) inhibitor, fasudil has positive effects on cardiovascular system. The present study was designed to determine the protective effect of fasudilon diabetic wound healing and investigate underlying mechanisms.METHODS In vivo, streptozotocin(STZ)-induced type 1 diabetic mice with full-thickness excisional wounds were intraperitoneally administered with 1, 3 or 10 mg·kg~(-1)·d~(-1) of fasudil. Wound closure, blood perfusion(doppler flow imaging), histomorphology(hematoxylin and eosin stain),angiogenesis(immunochemistry of CD31), reactive oxygen species(ROS)(Mito Sox and DHE) and NO production(Nitrite) were detected. In vitro, human umbilical vein endothelial cells(HUVECs) were exposed to high concen-trations of glucose(HG), treated with fasudil or si RNA of ROCK1. Endothelial function(tube formation assay),ROS(Mito Sox and DHE, Flow cytometry) were detected in HUVECs. The expression of key proteins was detected by Western blotting and quantitative real time polymerase chain reaction(q PCR). Histomorphology and key protein production of diabetics were also detected.RESULTS The protein levels of ROCK1 were increased both in diabetics, diabetic mice, and HUVECs. Fasudil dose-dependently rescued the delay of wound closure and increased the mean perfusion rate around the wound in diabetic mice. Diabetic conditions markedly increased mitochondrial oxygen superoxide anion(O_2·-)production and nitrotyrosine formation, decreased NO production and angiogenesis in wound tissues, which were normalized with 10 mg · kg~(-1) fasudil treatment. In HUVECs, treatment with fasudil and si RNA of ROCK1 significantly attenuated ROS production, increased expression of angiogenesis-associated genes and improved endothelial function under HG. Fasudil increased the ratio of p-AMPK/AMPK and p-e NOS/e NOS, decreased the expression and phosphorylation of Drp1 under HG in vivo and in vitro. Administration of compound C inverted the in vitro effects of fasudil or si RNA of ROCK1. CONCLUSION Fasudil rescued the delayed wound healing and improved wound angiogenesis in STZ-induced type 1 diabetic mice, at least in part, via AMPK/Drp1/e NOS pathway.     

Identification of bioactive anti-angiogenic constitutes targeting tumor endothelial cells in Shenmai Injection using multidimensional pharmacokinetics

OBJECTIVE To identify the bioactive anti-angiogenic constitutes targeting tumor endothelial cells(TECs) in Shenmai Injection(SMI). METHEODS For pharmacokinetic(PK) studies, Balb/c mice harboring human colorectal cancer(Lo Vo) xenografts were treated with SMI 10 m L·kg~(-1) daily for 1 or 8 d. Multidimensional PK profiles of ginsenosides in plasma, subcutaneous tumors, and TECs were investigated. For PD studies, the tumor-bearing micewere treated with SMI 10 mL ·kg~(-1) daily, Rd 0.5 and 5 mg·kg~(-1) daily, Rb1 5 mg·kg~(-1) daily and Rg1 5 mg·kg~(-1) daily for 14 d.Intravital multi-photon imaging and CD31 immunofluorescence staining were used to evaluate the number of microvessels and braches. Double staining of CD31 and α-SMA was performed to evaluate pericytes coverage ratios around vessels.ELISA was performed to determine the concentrations of VEGF and FGF in tumor tissues. For synergistic anti-tumor study, the tumor-bearing mice were treated with SMI 10 mL ·kg~(-1) daily, Rd 5 mg·kg~(-1) daily with or without 5-FU 15 mg·kg~(-1) every 3 d for 20 d. HPLC-MS/MS was used to determine the concentrations of 5-FU in plasma and tumor tissues.RESULTS SMI decreased the number of microvessels(P<0.05) and vessel branches(P<0.05) and improved vascular pericytes coverage(P<0.05). PK studies showed that the concentrations of protopanaxadiol-type(PPD) ginsenosides(Rb1, Rb2/Rb3, Rc, and Rd) in both, plasma and tumors, were higher than those of protopanaxatriol-type(Rg1 and Re)and oleanane-type(Ro) ginsenosides. Among PPD ginsenosides, Rd exhibited the greatest concentrations in tumors and TECs after repeated injection. In fact, the proportion of Rd in the detectable components of SMI gradually increased in the following order: SMI formula(2.8%), plasma(16.0%), tumor tissues(34.3%), and TECs(40.3%). In vivo bioactivity results showed that Rd 5 mg·kg~(-1) daily significantly decreased the number of microvessels(P<0.05) and vessel branches(P<0.05) and increased pericytes coverage(P<0.05) while Rd 0.5 mg·kg~(-1) daily, Rb1 and Rg1 had no significant effect on them. Rd 5 mg·kg~(-1) suppressed the expression of VEGF and FGF simultaneously. Rd 5 mg·kg~(-1) enhanced the antitumor effect of 5-FU via increasing the distribution of 5-FU in tumor tissues(P<0.05) in xenograft mice. CONCLUSION Ginsenoside Rd may be the major bioactive anti-angiogenic constituent targeting TECs after SMI treatment.     

Effect of rosmarinic acid on experimental diabetic nephropathy

Connective tissue growth factor (CTGF) plays a pathogenic role in diabetic nephropathy (DN). Rosmarinic acid (RA) is a naturally occurring phenolic acid. This study was conducted to investigate the efficacy of RA on DN and to elucidate the potential mechanism. High glucose (HG)-stimulated cultured human renal proximal tubular epithelial cells (HK-2) analysed CTGF expression by western blotting, and it was investigated whether extracellular signal-regulated kinase (ERK) signalling pathway was involved. Using streptozotocin (STZ)-induced rat animal models, diabetic rats were randomized to receive intragastric (i.g.) doses of RA. Renal tissue, blood and urine samples were collected to determine biochemical index and analyse protein expression. In vitro study, RA reduced CTGF excretion in HG-induced HK-2 cells through the ERK signalling pathway. In an in vivo study, I.g. of RA 7.5 or 15 mg/kg significantly ameliorated renal function and increased body-weight. Meanwhile, RA reduced renal CTGF expression by immunohistochemical staining and reduced serum levels of CTGF. Besides, there were no significant differences in glycaemia levels between the RA groups compared with the STZ-treated group. Furthermore, RA ameliorated renal pathology. These results suggest that RA exerts an early renal protective role to DN. Inhibition of CTGF may be a potential target in DN therapy, which highlights the possibility of using RA in the treatment of DN.     

Fungal metabolite nigerloxin ameliorates diabetic nephropathy and gentamicin-induced renal oxidative stress in experimental rats

Elevated polyol pathway enzyme activities and oxidative stress play an important role in the development and progression of diabetic nephropathy. Here, we investigated the beneficial influence of nigerloxin, a fungal metabolite and a potent aldose reductase inhibitor and free radical scavenger in the kidney of streptozotocin-induced diabetic rats. A group of diabetic rats was orally administered with nigerloxin for 30 days (100 mg/kg). Diabetic rats showed increased lipid peroxides, advanced glycation end products (AGEs), elevated activities of polyol pathway enzymes, and lowered antioxidant defense system in kidney. Administration of nigerloxin decreased kidney lipid peroxides and AGEs. Activities of polyol pathway enzymes were reduced while activities of all antioxidant enzymes, glutathione, and ascorbic acid were elevated in the kidney of nigerloxin-treated diabetic rats. We also investigated antioxidant potential of nigerloxin in gentamicin-induced nephrotoxicity in Wistar rats. Groups of rats were orally administered with nigerloxin for 8 days (25 mg or 100 mg kg^?1 body weight day^?1) along with gentamicin (80 mg/kg, i.p., for 8 days). Gentamicin induced increase in lipid peroxides, decrease in glutathione and activities of antioxidant enzymes in the kidney, and increase in blood creatinine, and urea concentrations were significantly countered by nigerloxin treatment. Thus, the results indicated the beneficial influence of nigerloxin on polyol pathway and oxidative stress associated with diabetes, which are implicated in ameliorating the development of diabetic nephropathy. Nigerloxin also ameliorated oxidative stress induced by gentamicin in the renal tissue.     

Rosiglitazone prevents advanced glycation end products-induced renal toxicity likely through suppression of plasminogen activator inhibitor-1.

In the development of diabetic nephropathy, advanced glycation end products (AGEs) play a causative role via induction of extracellular matrix (ECM) accumulation. Plasminogen activator inhibitor-1 (PAI-1), as a major inhibitor of plasminogen activator that plays an important role in degrading ECM, was found to significantly increase in renal fibrotic diseases. Activation of peroxisome proliferator-activated receptor (PPAR)-gamma prevented diabetic nephropathy. The present study, therefore, was to define whether or not AGE-induced renal ECM accumulation and renal dysfunction are mediated by upregulation of PAI-1 expression and whether or not PPAR-gamma agonist can attenuate these AGE effects via suppressing PAI-1 expression. Rats were given AGEs alone by iv injection at 100 mg/kg daily with or without oral supplementation of PPAR-gamma agonist rosiglitazone (RGZ) at 2 mg/kg daily for 6 weeks. Results showed that AGEs induced a renal ECM accumulation, as shown by increases in periodic acid-Schiff-positive materials, fibronectin, and type IV collagen (Col IV) contents in glomeruli, and a mild renal dysfunction, as shown by an increase in urinary proteins. AGEs also caused an increase in PAI-1 expression and a decrease in plasminogen activator bioactivity in the kidney. Treatment with RGZ significantly ameliorated AGE-induced renal ECM accumulation, proteinuria, and PAI-1 upregulation. Direct exposure of rat mesangial cells to AGEs in vitro induced increases in fibronectin and Col IV syntheses along with an increase in PAI-1 expression, effects significantly attenuated by RGZ. Preincubation of PAI-1 antibody to AGE-treated mesangial cells completely prevented AGE-induced fibronectin and Col IV production. These results suggest that upregulation of PAI-1 expression plays a critical role in AGE-induced renal ECM accumulation. Renal protection of RGZ from AGEs may be associated with the suppression of PAI-1 expression through PPAR-dependent and independent mechanisms.     

Protective effects of bendazac lysine on early experimental diabetic nephropathy in rats

Aim: To investigate the preventive and protective effects of bendazac lysine (BDL) on experimental early diabetic nephropathy (DN) rats. Methods: After an early DN model was induced by streptozotocin, rats were administered BDL at doses of 100, 200, and 400 mg/kg for 8 weeks. Blood glucose, microalbuminuria,kidney index, total antioxidative capacity, laminin, advanced glycation end products (AGE), aldose reductase (AR) activity, and the relative quantity of transforming growth factor β1 (TGF-β1) mRNA were measured by different methods.The ultrastructural morphology was observed by transmission electron microscope. Results: The physical behaviors of early DN rats were hypopraxia,cachexia, and polyuria, while those treated with high doses of BDL were vibrant and vigorous. For BDL-treated DN rats, when compared with vehicle-treated DN rats, the blood glucose level and the intensity of oxidative stress were ameliorated.Also, the microalbuminuria level, AGE either in serum or in renal, and AR activity were significantly reduced. Furthermore, the expression of TGF-β1 mRNA in the kidney cortex was declined and the thickness of glomerular base membrane was decreased significantly. The ultrastructure of glomerulus and mesangial matrix of BDL-treated DN rats were ameliorated. Conclusion: BDL has protective effects on several pharmacological targets in the progress of DN and is a potential drug for the prevention of early DN.     

The favorable effect of style of Zea mays L. on streptozotocin induced diabetic nephropathy

The effectivity of water extract from the style of Zea mays on diabetic nephropathy was investigated in the development of new natural medicinal resources. Streptozotocin (STZ) induced diabetic rats were used to evaluate the therapeutic effect of the style. Urinary albumin excretion and creatinine clearance were examined for diagnosis of diabetic nephropathy. From these results it was learned that the style of Z. mays prevented glomerular hyperfiltration. The present findings indicated that the water extract of the title material suppressed the progression of diabetic glomerular sclerosis in STZ-induced diabetic rat.     

白皮杉醇对糖尿病肾病大鼠ERK1/2通路及CTGF蛋白表达的影响

目的：探究白皮杉醇（PIC）对糖尿病肾病（DN）大鼠细胞外调节蛋白激酶（ERK1/2）通路及其调控的结缔组织生长因子（CTGF）蛋白表达的影响。方法：取健康雄性SD大鼠,采用高脂高糖喂养+腹腔注射链脲霉素建立大鼠DN模型,并将造模成功的50只SD大鼠随机分为模型组（DN组）、PIC低（50 mg·kg^-1）、中（100 mg·kg^-1）、高（200 mg·kg^-1）剂量组,阳性对照组（厄贝沙坦25 mg·kg^-1）,每组10只;另取10只大鼠,正常饲养,作为正常对照组。各组均于造模成功后开始给药,PIC低、中、高剂量组及阳性对照组分别灌胃给予相应剂量的PIC及厄贝沙坦溶液,正常对照组和DN组灌胃给予10 mL·kg^-1生理盐水,各组大鼠连续给药4周,每天1次。给药期间观察大鼠饮食状况,于末次给药12 h后,称重、收集大鼠尿液,麻醉处死大鼠,取腹主动脉血和肾脏组织;用酶联免疫吸附（ELISA）试剂盒检测血液肾功能指标血清肌酐（Scr）、血清尿素氮（BUN）、空腹血糖及尿液中24 h尿蛋白量及空腹血糖（FBG）含量;取肾脏组织,称重,并用苏木精-伊红染色法检测大鼠肾脏组织病理形态;用黄嘌呤氧化酶法、硫代巴比妥酸缩合法检测肾组织氧化指标超氧化物歧化酶（SOD）活性、丙二醛（MDA）含量;用蛋白免疫印迹法（Western Blot）检测肾脏组织缺氧诱导因子-1α（HIF-1α）、血红素加氧酶-1（HO-1）、ERK1/2、CTGF蛋白相对表达水平。结果：与正常对照组相比,DN组大鼠精神萎靡、形体消瘦及肾小球基底膜增厚、肾小管扩张、肾间质炎性浸润等病理损伤严重,肾脏/体质指数、FBG、血清Scr和BUN、尿液中24 h尿蛋白量、肾脏组织中MDA含量、HIF-1α、HO-1、p-ERK1/2、CTGF蛋白表达升高（P<0.05）,SOD活性明显降低（P<0.05）;与DN组相比,PIC低、中、高剂量组及阳性对照组大鼠精神萎靡、形体消瘦及肾小球基底膜增厚、肾小管扩张、肾间质炎性浸润等病理损伤现象缓解,肾脏/体质指数、FBG、血清Scr和BUN、尿液中24 h尿蛋白量、肾脏组织中MDA含量、HIF-1α、p-ERK1/2、CTGF蛋白表达降低（P<0.05）,HO-1、SOD活性明显升高（P<0.05）,且PIC各剂量组上述指标呈剂量依赖性。阳性对照组上述指标变化与PIC组相比差异无统计学意义。结论：PIC可抑制ERK1/2-CTGF信号通路激活,升高HO-1表达、降低HIF-1α表达,抑制肾脏氧化应激损伤,改善DN大鼠肾脏损伤     

糖尿病大鼠肾组织AGEs、MDA等生化指标变化与糖尿病肾病的关系研究

目的探讨糖尿病大鼠血糖及肾组织中糖基化终末产物（AGEs）、丙二醛（MDA）、超氧化物歧化酶（SOD）等生化指标的变化与糖尿病肾病（DN）的发生关系。方法采用腹腔注射链脲佐茵素建立糖尿病大鼠模型,观察其血糖、肾功能和肾组织中AGEs、MDA、SOD等的变化。结果糖尿病大鼠空腹血糖、尿蛋白、血肌酐、尿素氮及AGEs、MDA明显增高,而体重、肌酐清除率、肾组织SOD活力显著下降。结论糖尿病大鼠的持续高血糖,引起肾脏的氧化应激和非酶糖基化反应增强,与DN的发生和发展密切相关。     

Diabetic nephropathy,renal hemodynamics,and aldose reductase inhibitors

Diabetic kidney disease or diabetic nephropathy is the leading cause of renal failure in the United States today. This review presents a brief overview of diabetic nephropathy—its current statistics, histopathology, natural history, and main risk factors, including hyperglycemia, hyperfiltration, and hypertension. Pathogenic mechanisms by which hyperglycemia, severe hyperfiltration, and capillary hypertension might cause renal injury are discussed. Evidence is reviewed indicating a potentially useful role for aldose reducatase inhibitors (ARIs) to normalize or reduce the impact of two possible risk factors for diabetic nephropathy, namely, elevated polyol pathway metabolism and severe hyperfiltration. Measurements in experimental models of whole kidney blood flow (⁵⁷Co-microspheres, clearance methods), superficial cortical blood flow (laser Doppler flowmetry), and single nephron hemodynamic parameters (renal micropuncture) concordantly indicate that the beneficial effect of ARIs on hyperfiltration is based on protection or restoration of normal renal microvascular resistance. Since ARIs affect neither blood sugar levels nor mean arterial pressure, ARIs have no increased risk attributable to hypoglycemia or hypotension. It is concluded that ARIs warrant further experimental and clinical research in early diabetic nephropathy.     

Inhibitory effects of two major isoflavonoids in Radix Astragali on high glucose-induced mesangial cells proliferation and AGEs-induced endothelial cells apoptosis

Radix Astragali, the dried roots of Astragalus membranaceus var. mongholicus, is well known to have a protective effect on diabetic nephropathy. However, the effects of isoflavonoids in Radix Astragali on glomerular cells, which play a key role in the development of diabetic vascular complications, remain largely unknown. Thus, the purpose of this study was to investigate in vitro the effect of calycosin and calycosin-7-O-β-D-glucoside, two major isoflavonoids in Radix Astragali, on high glucose-induced rat mesangial cells proliferation and AGEs-induced human glomerular endothelial cell apoptosis. The results indicated that both calycosin and calycosin-7-O-β-D-glucoside (10-100 μM) could inhibit high glucose-induced mesangial cell early proliferation. Additionally, AGEs-mediated cell apoptosis was also attenuated by treatment of glomerular endothelial cells with either calycosin or calycosin-7-O-β-D-glucoside (1-100 μM). Therefore, the results obtained in this study suggest that both calycosin and calycosin-7-O-β-D-glucoside have a significant therapeutic potential to modulate the development and/or progression of diabetic nephropathy.     

Effects of dopamine prodrugs and fenoldopam on glomerular hyperfiltration in streptozotocin-induced diabetes in rats.

The effects of dopamine (DA) prodrugs (L-dopa and gludopa) and of a D1-selective agonist (fenoldopam) on glomerular hyperfiltration were studied in the early stage of diabetes in rats. Wistar rats received one injection of streptozotocin (STZ) and were treated 1 week later with L-dopa (2 x 10 mg/kg/day, s.c.), gludopa (2 x 3 or 2 x 10 mg/kg/day, s.c.), or fenoldopam (2 x 0.3 or 2 x 1 mg/kg/day, s.c.). Their renal functions were compared with those of untreated diabetic and nondiabetic control rats. STZ injection led to hyperglycemia that was kept moderate (20-25 mmol/L) by daily insulin therapy (2-4 U of NPH insulin). Within 2 weeks, glomerular hyperfiltration (polyfructosan clearance) developed in diabetic rats (30% increase vs. nondiabetic control). A rise in renal plasma flow (PAH clearance) was sometimes observed. One week of treatment with either L-dopa, gludopa, or fenoldopam normalized the glomerular filtration rate and decreased filtration fraction. These corrections occurred despite similar metabolic disturbance and kidney hypertrophy. Gludopa was less well tolerated by diabetic rats than L-dopa. Results with L-dopa showed that the normalization of glomerular hyperfiltration was linked to DA synthesis and stimulation of D1 receptors, since it was reversed by carbidopa, a dopa decarboxylase inhibitor, and by SCH 23390, a D1-selective antagonist. These data show that DA prodrugs and a D1 agonist can suppress diabetic glomerular hyperfiltration in the very early course of the disease in rats.     

替米沙坦对冠心病合并糖尿病肾病肾功能、心功能、炎症反应及血管内皮功能的影响分析

目的 探讨替米沙坦治疗冠心病(CHD)合并糖尿病肾病(DN)患者的临床效果.方法 选取88例CHD合并DN患者,采用随机数字表法分为观察组和对照组,各44例,两组患者的基础治疗均保持一致,观察组给予替米沙坦80 mg·d-1,对照组给予依那普利10 mg·d-1,疗程3个月.结果 治疗前,两组患者的血浆内皮素-1(ET-1)、一氧化氮(NO)、白细胞介素-6(IL-6)、基质金属蛋白酶-9(MMP-9)检测值均差异无统计学意义(P>0.05);治疗后,观察组患者的ET-1、IL-6、MMP-9检测值均显著的低于对照组(P<0.05),NO检测值显著的高于对照组(P<0.05);治疗前,两组患者的左室射血分数(LVEF)、左室舒张末期内径(LVEDd)均差异无统计学意义(P>0.05);治疗后,观察组患者的LVEDd值显著的低于对照组(P<0.05),LVEF值显著的高于对照组(P<0.05);治疗前,两组患者的血肌酐(Scr)、24 h尿蛋白值均差异无统计学意义(P>0.05);治疗后,观察组患者的Scr、24 h尿蛋白值均显著的低于对照组(P<0.05).结论 替米沙坦治疗CHD合并DN患者的效果优于依那普利,能够更显著的改善内皮功能、心功能及肾功能.