灵芝多糖肽对ECV304细胞氧化损伤的保护作用

目的研究灵芝多糖肽对ECV304氧化损伤的保护作用。方法培养ECV304细胞,以叔丁基氢过氧化物(tBOOH)为氧化剂损伤细胞,造成氧化损伤模型,培养液中加入不同浓度灵芝多糖(12.5、25、50、100mg.L-1),以MTT法测细胞存活率;以光镜、电镜检测细胞形态学改变及线粒体损伤;用AnnexinV/PI双标记细胞,流式细胞检测细胞凋亡的百分率。结果灵芝多糖(12.5、25、50、100mg.L-1)可减少叔丁基氢过氧化物对ECV304的氧化损伤,MTT检测灵芝多糖给药组,ECV304细胞存活率增加。光镜下可见细胞损伤减少,电镜可见灵芝多糖(50mg.L-1,温育24h)减轻细胞器如线粒体氧化损伤,减少细胞凋亡。细胞流式检测表明:对照组、给药组、损伤组总凋亡百分率分别2.24%±0.43%、24%±6.4%(P<0.01)、82.1%±7.9%。结论灵芝多糖肽(GLPP)对ECV304细胞氧化损伤具有保护作用。     

大鼠急性肾缺血再灌注时心肌细胞氧化损伤及瑞芬太尼的干预作用

目的观察大鼠急性肾缺血再灌注时心肌细胞氧化损伤以及瑞芬太尼预处理对氧化损伤的干预作用。方法建立大鼠肾缺血再灌注损伤模型。将54只Wistar大鼠随机分为假手术组(Sham组)、缺血再灌注组(I/R组)、瑞芬太尼预处理组(R组)。Sham组只结扎单侧肾脏,另一侧只穿线不结扎;I/R组结扎右侧肾脏,动脉夹夹闭左侧肾蒂45min后开放,于再灌注30min、1、2、3h处死大鼠;R组为缺血前以1μg·kg-1·min-1微泵输注瑞芬太尼30min进行预处理,余同I/R组。分别检测各组大鼠心肌组织超氧化物歧化酶(SOD)活力、丙二醛(MDA)含量及谷胱甘肽过氧物酶(GSH-Px)活力变化。结果I/R组、R组与Sham组相比,心肌组织MDA含量升高,SOD、GSH-Px活力降低,且在1、2、3h时间点,差异均有统计学意义(P<0.05)。R组与I/R组比较,心肌组织MDA含量降低,SOD、GSH-Px的表达增高,且差异有统计学意义(P<0.05)。结论大鼠急性肾缺血再灌注可造成心肌细胞氧化损伤,而瑞芬太尼预处理可起到一定的保护作用。     

三七总皂苷预处理对急性期缺血再灌注肾脏的保护作用

目的 探索三七总皂苷预处理对急性期肾缺血再灌注损伤的作用.方法 取75只SD雄性大鼠,随机分为3组,每组25只,分为:假手术组(C组)、缺血再灌注损伤组(RIRI组)、三七总皂苷组(PNS组).实验干预:(1)C组:实验前尾静脉注射与PNS组等量生理盐水,1次/d,共3d,麻醉后右肾切除,左肾暴露30 min后关腹;(2)RIRI组:切除右侧肾脏,左侧肾动脉夹闭30 min后恢复血流;(3)PNS组:实验前尾静脉注射PNS(150 mg/kg),其余同RIRI组.在缺血再灌注前1h及再灌注后1,6,12,24 h等5个时间点分别取5只大鼠,取血清测肌酐、尿素氮,肾组织匀浆检测肾组织超氧化物歧化酶活性(SOD)、丙二醛(MDA)含量,光镜下观察肾组织的病理变化,并分别进行比较.结果 与C组比较,RIRI组的肌酐、尿素氮、MDA水平在再灌注24 h内随着时间的延长逐渐升高,SOD活性则明显降低.PNS组的肌酐、尿素氮、MDA水平在再灌注6h后各组与RIRI组比较降低,SOD活性明显增强.结论 PNS对肾缺血再灌注损伤具有保护作用,其保护作用机制与增强SOD活性、清除自由基等有关.     

L-精氨酸对大鼠肾缺血再灌注损伤细胞凋亡的影响

目的探讨左旋精氨酸(L-arginine,L-arg)对大鼠肾缺血再灌注损伤(RIRI)细胞凋亡的影响.方法采用夹闭双侧肾动、静脉45 min后松夹再灌的方法制作RIRI模型,测定血清肌酐(Scr)、丙二醛(MDA)、一氧化氮(NO)及尿NAG酶(UNAG)含量,观察肾组织形态学改变和肾皮质细胞凋亡率.结果缺血再灌注后6和24 h,大鼠肾功能和肾小管上皮细胞明显受损,Scr、MDA和UNAG含量均明显高于假手术组(P＜0.01),肾皮质细胞凋亡率明显增加.尾静脉注射L-arg可明显改善RIRI大鼠肾功能,减轻肾损伤,并明显降低肾皮质细胞凋亡率(P＜0.05).结论 L-arg可通过增加体内NO水平,抑制肾小管上皮细胞凋亡对大鼠RIRI起到一定的保护作用.     

C1q/TNF-related protein 6 (CTRP6) attenuates renal ischaemia-reperfusion injury through the activation of PI3K/Akt signalling pathway

C1q/TNF-related protein 6 (CTRP6) is a member of the CTRP family that has been reported to exhibit a nephroprotective effect. However, the role of CTRP6 in renal ischaemia/reperfusion (I/R) injury (IRI) remains unclear. In the present study, we aimed to explore the protective effect of CTRP6 in renal IRI and the potential mechanism. We found that CTRP6 expression was markedly decreased in the kidneys of mice subjected to I/R and HK-2 cells in response to hypoxia/reoxygenation (H/R) stimulation. Recombinant CTRP6 protein protected against renal I/R injury by the reduction of blood urea nitrogen (BUN) and creatinine levels. The increased production of ROS and malondialdehyde (MDA), as well the decreased activities of glutathione peroxidase (GPx) and superoxide dismutase (SOD) caused by H/R induction were mitigated by CTRP6 in HK-2 cells. The caspase-3 activity and apoptotic rate were both decreased in CTRP6-overexpressing HK-2 cells. In addition, we also found that knockdown of CTRP6 aggravated H/R-caused oxidative stress and cell apoptosis in HK-2 cells. Moreover, CTRP6 overexpression enhanced the H/R-stimulated activation of PI3K/Akt pathway in HK-2 cells. Inhibition of PI3K reversed the nephroprotective effects of CTRP6 in HK-2 cells. Taken together, CTRP6 exerted protective effects against H/R-caused oxidative injury in HK-2 cells via activating the PI3K/Akt pathway.     

Berberine protects HK-2 cells from hypoxia/reoxygenation induced apoptosis via inhibiting SPHK1 expression

Renal ischemia reperfusion injury (RIRI) refers to the irreversible damage for renal function when blood perfusion is recovered after ischemia for an extended period, which is common in clinical surgeries and has been regarded as a major risk for acute renal failures (ARF) that is accompanied with unimaginably high morbidity and mortality. Hypoxia during ischemia followed by reoxygenation via reperfusion serves as a major event contributing to cell apoptosis, which has been widely accepted as the vital pathogenesis in RIRI. Preventing apoptosis in renal tubular epithelial cell has been considered as effective method for blocking RIRI. In this paper, we established a hypoxia/reoxygenation (H/R) injury model in human proximal tubular epithelial HK-2 cells. Here, we found increased SPHK1 levels in H/R injured HK-2 cells, which could be significantly down regulated after berberine treatment. Berberine has been reported to exert a protective effect on H/R-induced apoptosis of HK-2 cells. So, in our present study, we planned to investigate whether SPHK1 participated in the anti-apoptosis process of berberine in H/R injured HK-2 cells. Our study confirmed the protective effect of berberine against H/R-induced apoptosis in HK-2 cells through promoting cells viability, inhibiting cells apoptosis, and down-regulating p-P38, caspase-3, caspase-9 as well as SPHK1, while up regulating the ratio of Bcl-2/Bax. However, SPHK1 overexpression in HK-2 cells induced severe apoptosis, which can be significantly ameliorated with additional berberine treatment. We concluded that berberine could remarkably prevent H/R-induced apoptosis in HK-2 cells through down-regulating SPHK1 expression levels, and the mechanisms included the suppression of p38 MAPK activation and mitochondrial stress pathways.     

Berberine protects renal tubular cells against hypoxia/reoxygenation injury via the Sirt1/p53 pathway

Berberine (BBR) has been demonstrated to protect against renal ischemia/reperfusion injury; however, the underlying molecular mechanism is largely unknown. In the present study, we examined the role of silent information regulator 1 (Sirt1)/p53 in the protective effect of BBR on hypoxia/reoxygenation (H/R)-mediated mitochondrial dysfunction in rat renal tubular epithelial cells (NRK-52E cells). NRK-52E cells were preconditioned with small interfering RNA targeting Sirt1 (Sirt1-siRNA) and BBR before subjected to H/R. Cell damage was assessed by CCK8 assay and detection of oxidative parameters. The apoptotic rate was determined by flow cytometry and Hoechst 33258 staining. The expression of apoptotic markers, Sirt1, p53 and the translocation of p53 were examined by Western blotting assay. Nuclear p53 deacetylation by Sirt1 was detected using immunoprecipitation. Compared with the H/R group, BBR pretreatment increased cell viability and inhibited mitochondrial oxidative stress and apoptosis. Protein expression of Sirt1 was also enhanced along with a reduction of p53. Furthermore, both nuclear translocation of p53 and its acetylation were inhibited in NRK-52E cells pretreated with BBR. However, the knockdown of Sirt1 counteracted the renoprotection of BBR. BBR preconditioning protects rat renal tubular epithelial cells against H/R-induced mitochondrial dysfunction via regulating the Sirt1/p53 pathway.     

Sulforaphane protects kidneys against ischemia-reperfusion injury through induction of the Nrf2-dependent phase 2 enzyme

Reactive oxygen species are important mediators that exert a toxic effect during ischemia-reperfusion injury of various organs. Sulforaphane, which is a naturally occurring isothiocyanate that is present in cruciferous vegetables such as broccoli, is known to be an indirect antioxidant that acts by inducing Nrf2-dependent phase 2 enzymes. Phase 2 enzymes such as heme oxygenase-1, NAD(P)H: quinone oxidoreductase 1, glutathione reductase, and glutathione peroxidase participate in adaptive and protective responses to oxidative stress and various inflammatory stimuli. Therefore, we evaluated the preactivation of Nrf2 by sulforaphane to determine if it could inhibit ischemia-reperfusion-induced kidney damage. Treatment of HK2 renal tubular epithelial cells with sulforaphane effectively protected cells against cytotoxicity induced by hypoxia-reoxygenation, and sulforaphane dramatically induced phase 2 enzymes by decreasing the Keap1 protein levels and increasing Nrf2 nuclear translocation. Additionally, a second set of experiments using a renal ischemia-reperfusion model produced results that were essentially the same as those observed when HK2 cells were used; namely, that sulforaphane induced Nrf2-dependent phase 2 enzymes and thereby improved ischemia-reperfusion-induced changes in the lipid hydroperoxides, glutathione, creatinine clearance, kidney weight, and histologic abnormalities. Collectively, these results suggest that sulforaphane can be used as an effective adjunct for the prevention of renal oxidative insults during ischemia-reperfusion injury.     

葡萄籽原花青素对大鼠肾缺血再灌注损伤的保护作用

目的探讨葡萄籽原花青素(Grape seed proanthocyanidin extract,GSPE)对大鼠急性肾缺血再灌注损伤的保护作用及其机制。方法32只SD大鼠随机分为4组,每组8只,分别为假实验组(SG),缺血再灌注组(I/RG),急性GSPE(450mg/kg灌胃1次)治疗+I/R组(ATG),慢性GSPE(150mg/kg灌胃喂养1周)治疗+I/R组(CTG)。采用一侧肾蒂结扎、另一侧肾动脉夹闭的肾缺血再灌注损伤模型,测定肾组织丙二醛(MDA)水平和超氧化物歧化酶(SOD)的活性,同时测定血清尿素氮(BUN)和肌酐(Cr)水平。结果I/RG与SG相比,MDA、BUN和Cr含量明显升高(P<0.05),SOD活性下降(P<0.05)。与I/RG相比,ATG的MDA和Cr含量下降(P<0.01,P<0.05),CTG的MDA、BUN和Cr含量明显下降(P<0.05,P<0.01),SOD活力显著升高(P<0.05)。结论葡萄籽原花青素对肾缺血再灌注损伤具有保护作用,其机制可能与抗自由基损伤有关。     

依达拉奉对肾缺血再灌注损伤的保护作用

目的探讨依达拉奉对肾脏缺血再灌注损伤的保护作用。方法将40只雄性Wistar大鼠随机分为假手术组(S组)、缺血再灌注组(I组)、EA组、EB组和EC组,其中除了S组外,其余大鼠均夹闭双侧肾蒂45min、再灌注24h制成肾缺血再灌注损伤动物模型。缺血前和再灌注即刻,EA组、EB组、EC组分别经尾静脉给予依达拉奉1mg/kg、3mg/kg、6mg/kg,S组和I组经尾静脉给予等量生理盐水。于再灌注24 h取股动脉血检测丙二醇(MDA)、超氧化物歧化酶(SOD)、尿素氮(BUN)、肌酐(Cre),取左肾免疫组织化学观察肾脏细胞凋亡。结果(1)EA组、EB组的MDA随依达拉奉剂量增大而降低(P<0.05),但EC组的MDA高于EB组(P<0.05);上述三组的MDA均低于I组(P<0.05)。(2)在SOD活力方面,EA组和I组之间、EB组和EC组之间无显著性差异(P>0.05),但EB组和EC组均高于EA组和I组(P<0.05)。(3)EA组、EB组的BUN、Cre之间比较无显著性差异(P>0.05),但均明显低于I组(P<0.05);而EC组的BUN、Cre与I组比较差异无显著性;(P>0.05)。(4)免疫组织化学显示,I组中肾脏细胞凋亡指数较S组上升,EB组则较I组下降(P<0.05)。结论大鼠肾脏缺血再灌注损伤时,依达拉奉能清除氧自由基、减少肾脏细胞凋亡,对肾脏缺血再灌注损伤具有保护作用。     

Urantide对缺血/再灌注损伤诱导的心肌细胞凋亡的影响(英文)

目的探讨urantide对大鼠心肌缺血/再灌注(I/R)或缺氧/复氧损伤(H/R)诱导的心肌细胞凋亡的影响及其相关机制。方法①在体实验采用冠状动脉左前降支缺血30 min/灌注60 min法建立大鼠在体心肌I/R模型。Urantide 3,10和30μg.kg-1分别于缺血前10 min经舌下静脉给药。TUNEL法检测心肌细胞凋亡,免疫组织化学方法检测心肌细胞内Bcl-2和Bax蛋白的表达水平。②离体实验乳大鼠心肌细胞行缺氧3 h/复氧3 h处理制备H/R模型。Urantide 0.1,1和10 nmol.L-1分别于缺氧前加入。Ho-echst33258染色和流式细胞术检测心肌细胞凋亡。结果①在体实验与假手术组相比,I/R组TUNEL阳性细胞数量明显升高(P<0.01);Bcl-2蛋白表达量轻度升高,但无统计学差异,Bax蛋白表达量显著升高(P<0.01),Bcl-2/Bax比值明显降低(P<0.01)。与I/R组相比,urantide 10,30μg.kg-1组心肌凋亡细胞显著降低,分别较模型组降低36.6%和57.2%(P<0.05);Bax蛋白表达量显著降低(P<0.05),Bcl-2/Bax比值明显升高(P<0.05);同时,urantide 30μg.kg-1组Bcl-2蛋白表达量也明显升高(P<0.05)。②离体实验与正常对照组相比,H/R组细胞凋亡率明显升高(P<0.01);Hoechst33258结果显示,与模型组相比,uran-tide 0.1,1和10 nmol.L-1组细胞凋亡率分别显著降低了27.9%,59.0%和75.4%(P<0.05)。流式细胞术结果显示,urantide 1和10 nmol.L-1组细胞凋亡率显著降低,分别较H/R模型组降低32.8%和64.7%(P<0.01)。结论 Urantide可减轻I/R或H/R损伤诱导的心肌细胞凋亡,其机制可能与增加Bcl-2蛋白表达,降低Bax蛋白表达有关。     

Salvianolic acid A ameliorates AGEs-induced glomerular endothelial dysfunction and protects against diabetic nephropathy

OBJECTIVE Diabetic nephropathy(DN)has been one of the most common complications of diabetes and the leading cause of end-stage renal disease.Glomerular hyperfiltrationis central in earlystage of DN and leads to the progression of renal architectonic and functional abnormalities.Salvianolic acid A(SalA)has been proved to protect diabetic complications such as hepatic fibrosis and neuropathy.The present study was designed to investigate the effects of SalA on glomerular endothelial dysfunctionand diabetic nephropathy.METHODS Primary glomerular endothelial cells were subjected to assess permeability under injury of advanced glycation end-products(AGEs).AGEs-induced changes of Rho A/ROCK pathway and cytoskeleton rearrangement were assessed bywestern blotandimmunofluorescence.The beneficial effects of SalA on diabetic nephropathy were investigated in a rat model induced by high-fat and high-glucose diet combined with low dose of streptozocin(35 mg·kg~(-1),ip).Renal function and architectonic changes were evaluated by biochemical assay and PAS staining.RESULTS SalA 3μMameliorated AGEs-induced glomerular endothelial permeability(P<0.05)and suppressed rearrangement of cytoskeleton through inhibiting AGE-RAGE-Rho A/ROCK pathway.SalA1 mg·kg~(-1)markedly reduced endothelium loss(P<0.01)and glomerular hyperfiltration(P<0.05)in diabetic kidney.Subsequently,SalA 1 mg·kg~(-1) suppressed glomerular hypertrophy and mesangial matrix expansion,eventually reduced 24 h-urinary albumin and ameliorated renal function by decreasing blood urine nitrogen(BUN),serum creatinine(Scr)and serum n-acetyl-β-d-glucosaminidase(NAG).AGEs-RAGE-Nox4-induced oxidative stress was suppressed by the treatment of SalA 1 mg·kg~(-1).CONCLUSION SalA ameliorated AGEs-induced glomerular endothelial hyperpermeability,and effectively protected against early-stage diabetic nephropathy by reducing hyperfiltration and alleviating renal structural deterioration through inhibiting AGEs and its downstream pathway.Thus,SalA might be a promising therapeutic agent for the treatment of diabetic nephropathy.     

马来酸罗格列酮对肾缺血再灌注损伤模型小鼠的保护作用及其机制研究

目的:探讨马来酸罗格列酮对肾缺血再灌注损伤模型小鼠的保护作用及其机制。方法:小鼠30只随机分为假手术组(生理盐水)、模型组(生理盐水)和马来酸罗格列酮组(5 mg.kg-1.d-1),灌胃给予相应药物,连续10 d,末次给药40 min后除假手术组外建立肾缺血再灌注损伤模型,术后检测肾脏指数,血清尿素氮(BUN)、肌酐(Cr)、肾组织中丙二醛(MDA)的含量及超氧化物歧化酶(SOD)、谷胱甘肽过氧化物酶(GSH-Px)活力,常规HE染色观察肾组织病理变化。结果:与模型组比较,马来酸罗格列酮组小鼠肾脏指数降低(P<0.01),血清BUN、Cr、肾组织中MDA含量均减少(P<0.01),SOD和GSH-Px活力增加(P<0.01或P<0.05)。结论:马来酸罗格列酮对小鼠肾缺血再灌注损伤具有保护作用,其机制可能与减轻自由基引起的肾组织脂质过氧化反应有关。     

沙棘油和亚硒酸钠对汞诱导的大鼠肝肾氧化损伤的影响

目的通过汞诱导大鼠肝肾氧化损伤,观察沙棘油(Sea Buckthorn Oil,SBO)和亚硒酸钠(Na2SeO3)干预效应。方法Wister大鼠随机分成对照组、单纯染汞组、SBO和Na2SeO3处理组。测定肝、肾及尿中汞含量,肝、肾中GSH、MDA、蛋白含量和SOD、GSH-PX活力。结果与单纯染汞组相比,SBO处理组尿汞含量增加(P<0.05),肝GSH-PX活力升高(P<0.01);Na2SeO3处理组肝汞增加,肾和尿汞含量下降,肝GSH-PX活力、GSH含量均升高(P<0.01),肝SOD活力和肾GSH-PX活力均增加(P<0.05),肾MDA含量下降(P<0.05)。结论沙棘油具有促进汞从肾脏排出的作用,对汞诱导的肝氧化损伤具有一定保护作用,对肾氧化损伤未表现出明显的保护作用。Na2SeO3可有效拮抗汞诱导的肝肾氧化损伤作用。     

Fibroblast growth factor 10 ameliorates renal ischaemia–reperfusion injury by attenuating mitochondrial damage

Ischaemia–reperfusion (I/R) injury is one of the leading causes of acute kidney injury (AKI). Its pathologic mechanism is quite complex, involving oxidative stress, inflammatory response, autophagy, and apoptosis. Fibroblast growth factor 10 (FGF10) and 5-hydroxydecanoate (5-HD) play essential roles in kidney injury. Rats were divided into four groups: (i) sham group, sham-operated animals with an unconstructed renal artery; (ii) I/R group, kidneys were subjected to 50 min of ischaemia followed by reperfusion for 2 days; (iii) I/R + FGF10 group, animals treated with 0.5 mg/kg FGF10 (i.p.) 1 h before ischaemia; and (iv) 5-HD group, animals treated with 5 mg/kg 5-HD (i.m.) 30 min before FGF10 treatment. Renal injury, apoptosis damage, mitochondrial oxidative damage, mitochondrial membrane potential (MMP), and expression of the ATP-sensitive K+ (KATP) channel subunit Kir6.2 were evaluated. FGF10 treatment significantly alleviated I/R-induced elevation in the serum creatinine level and the number of terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling–positive tubular cells in the kidney. In addition, FGF10 dramatically ameliorated renal mitochondrial-related damage, including reducing mitochondrial-dependent apoptosis, alleviating oxidative stress, maintaining the mitochondrial membrane potential, and opening the mitochondrial KATP channels. The protective effect of FGF10 was significantly compromised by the ATP-dependent potassium channel blocker 5-HD. Our data suggest that FGF10 offers effective protection against I/R and improves animal survival by attenuating mitochondrial damage.     

丹参大鼠肢体缺血再灌注后多器官水肿的预防作用

【摘要】 目的：探讨氧化应激（oxidative stress）在大鼠肢体缺血再灌注（LIR）致多器官水肿中的作用及丹参的影响。方法：Wistar大鼠24只随机分为三组（n=8）:对照组（C组）、缺血再灌注组（I/R组）和丹参预处理组(SM组)。以止血带法制作大鼠肢体缺血再灌注模型,SM组在再灌注前30min经尾静脉推注丹参注射液5ml／kg。手术准确留取每只动物的心、肝、肾、肺、脑、肠及骨骼肌组织各1g,恒温烘干后称其干重并计算各标本的湿干重比值(W/D)。采用生物化学方法测定血浆SOD、XOD活性及MDA含量。光镜下观察各组织的形态学变化。结果：LIR后各组织W/D均增加（P<0.01或P<0.05）,血浆SOD活性降低而XOD活性和MDA含量增加（P<0.01或P<0.05）,各组织镜下可见不同程度的结构紊乱、组织间隙增宽和炎细胞浸润等病理改变。而SM组与单纯再灌注组比较,血浆SOD活性回升而XOD活性和MDA含量降低（P<0.01或P<0.05）,镜下组织病理学变化有所减轻。结论：大鼠肢体缺血再灌注可导致多器官水肿,氧化应激是其重要机制之一。丹参可通过抗氧化在此过程中发挥抗水肿作用。     

Inhibitors of calpain activation (PD150606 and E-64) and renal ischemia-reperfusion injury

Calpain activation has been implicated in the development of ischemia-reperfusion (I-R) injury. Here we investigate the effects of two inhibitors of calpain activity, PD150606 and E-64, on the renal dysfunction and injury caused by I-R of rat kidneys in vivo. Male Wistar rats were administered PD150606 or E-64 (3mg/kg i.p.) or vehicle (10%, v/v, DMSO) 30min prior to I-R. Rats were subjected to bilateral renal ischemia (45min) followed by reperfusion (6h). Serum and urinary biochemical indicators of renal dysfunction and injury were measured; serum creatinine (for glomerular dysfunction), fractional excretion of Na(+) (FE(Na), for tubular dysfunction) and urinary N-acetyl-beta-d-glucosaminidase (NAG, for tubular injury). Additionally, kidney tissues were used for histological analysis of renal injury, immunohistochemical analysis of intercellular adhesion molecule-1 (ICAM-1) expression and nitrotyrosine formation. Renal myeloperoxidase (MPO) activity (for polymorphonuclear leukocyte infiltration) and malondialdehyde (MDA) levels (for tissue lipid peroxidation) were determined. Both PD150606 and E-64 significantly reduced the increases in serum creatinine, FE(Na) and NAG caused by renal I-R, indicating attenuation of renal dysfunction and injury and reduced histological evidence of renal damage caused by I-R. Both PD150606 and E-64 markedly reduced the evidence of oxidative stress (ICAM-1 expression, MPO activity, MDA levels) and nitrosative stress (nitrotyrosine formation) in rat kidneys subjected to I-R. These findings provide the first evidence that calpain inhibitors can reduce the renal dysfunction and injury caused by I-R of the kidney and may be useful in enhancing the tolerance of the kidney against renal injury associated with aortovascular surgery or renal transplantation.     

FK506对肾脏缺血再灌注损伤预防与治疗作用的实验研究

目的探讨FK506对Wistar大鼠肾脏缺血再灌注损伤的预防与治疗作用。方法建立30只Wistar大鼠肾脏缺血再灌注模型,随机分为预防组、治疗组和对照组,前两组经肠系膜上静脉给予FK506,剂量为0.1mg/kg,对照组给予等量生理盐水,分别检测各组大鼠血液中尿素氮(BUN)、肌酐(Cr)浓度,检测肾脏组织中MDA、SOD含量,观察肾脏组织学变化并进行改良Miller's评分。结果预防组与治疗组血BUN、Cr值和Miller's评分之间的差异无显著性意义(P>0.05),但均明显低于对照组(P<0.01);组织学观察显示前两组大鼠肾小管上皮细胞坏死程度明显减轻;预防组与治疗组MDA含量明显低于对照组(P<0.01),SOD含量明显高于对照组(P<0.01),但两组间差别无显著性意义(P>0.05)。结论FK506能够有效地保护缺血再灌注肾脏的结构和功能,为临床应用提供了可靠的理论基础。     

Differential effects of caspase inhibitors on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney

Caspase activation has been implicated in the development of ischemia-reperfusion injury. Here, we investigate the effects of different caspase inhibitors on the renal dysfunction and injury caused by ischemia-reperfusion of the rat kidney. Bilateral clamping of renal pedicles (45 min) followed by reperfusion (6 h) caused significant renal dysfunction and marked renal injury. Caspase-1 inhibitor II (N-acetyl-L-tyrosyl-L-valyl-N-[(1S)-1-(carboxymethyl)-3-chloro-2-oxo-propyl]-L-alaninamide, Ac-YVAD-CMK, 3 mg/kg, administered i.p.) significantly reduced biochemical and histological evidence of renal dysfunction and injury. However, although caspase-3 inhibitor I (N-acetyl-L-aspartyl-L-glutamyl-N-(2-carboxyl-1-formylethyl]-L-valinamide, Ac-DEVD-CHO, 3 mg/kg, administered i.p.) produced a significant improvement of renal (glomerular) dysfunction (reduction of serum creatinine levels), it was not able to reduce tubular dysfunction and injury. Furthermore, the pan-caspase inhibitor caspase inhibitor III (N-tert-butoxycarbonyl-aspartyl(OMe)-fluoromethylketone, Boc-D-FMK, 3 mg/kg, administered i.p.) did not reduce renal dysfunction and injury. Both caspase-1 and -3 inhibitors markedly reduced the evidence of oxidative and nitrosative stress in rat kidneys subjected to ischemia-reperfusion. Overall, these results demonstrate that inhibition of caspase-1 reduces renal ischemia-reperfusion injury to a greater extent than caspase-3 inhibition, supporting the notion that the mode of acute cell death in our model of renal ischemia-reperfusion is primarily via necrosis. Furthermore, our finding that a pan-caspase inhibitor did not reduce the renal dysfunction and injury suggests that activation of some caspases during ischemia-reperfusion could provide protection against acute ischemic renal injury. Overall, these results demonstrate that inhibition of caspase-1 activity reduces renal ischemia-reperfusion injury and that this therapeutic strategy may be of benefit against ischemic acute renal failure.