Curcumin protects against ischemia/reperfusion injury in rat kidneys

OBJECTIVES: Renal ischemia followed by reperfusion leads to acute renal failure in both native kidneys and renal allograft. We investigated the effect of curcumin on ischemia-reperfusion (I/R) injury and the antioxidant effects of curcumin in rats. METHODS: Thirty rats were randomly divided into five experimental groups (control, sham, curcumin, I/R and I/R+curcumin, n=6 each). Curcumin was administered (200 mg kg(-1)) orally to curcumin and I/R+curcumin groups for 7 days. Then, the rats were subjected to bilateral renal ischemia for 45 min and followed by reperfusion for 24 h. All rats were killed and kidney function tests, serum and tissue nitric oxide (NO), protein carbonyl (PC), malondialdehyde (MDA), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels were determined. Histopathological examinations were also performed. RESULTS: Curcumin significantly improved the urea and cystatin C levels in I/R+curcumin group compared to I/R group (p<0.05). Reduction of serum GSH-Px was significantly improved by curcumin (p<0.001), but SOD enzyme activity did not alter (p>0.05). Treatment with curcumin also resulted in significant reduction in serum and tissue MDA, NO and PC and for tissue that were increased by renal I/R injury (p<0.001 for serum and p<0.05 for tissue, respectively). In histological examination, the rats treated with curcumin had nearly normal morphology of the kidney. CONCLUSIONS: Based on our results, it can be concluded that curcumin protects the kidneys against I/R injury via its antioxidant effects.     

氯胺酮对大鼠全肝缺血/再灌注后肺损伤的保护作用及机制

目的 观察10 mg/kg氯胺酮对于大鼠全肝缺血/再灌注诱发的急性肺损伤保护作用及其机制.方法 30只9～10周龄雌性SD大鼠以区组随机法随机分为3组(每组10只),假手术组(Sham组),全肝缺血/再灌注组(IR组)以pringle's法阻断门静脉和肝动脉30 min后再灌注1h.全肝缺血/再灌注氯胺酮预处理组(Ket组),以10 mg/kg氯胺酮于全肝血流阻断前20 min经尾静脉注射预处理.测定各组肺组织干湿重比值(W/D比值);血清中天冬氨酸氨基转移酶(AST)、血清丙氨酸氨基转移酶(ALT)含量;逆转录/实时聚合酶链式反应( RT-PCR)法测定肺组织中血清肿瘤坏死因子-α(TNF-α)mRNA、细胞间黏附分子-1( ICAM-1 )mRNA含量;Western blot法测定肺组织中核因子-kb( NF-kJ )/P65含量;各组肺组织HE染色后病理评分.结果 血清AST、ALT含量:IR组[AST:(91±25)U/ml,ALT:(67.0±19.4) U/ml]和Ket组[AST:(85±12) U/ml,ALT:(51.3±9.9) U/ml]均高于Sham组[AST:(29±9) U/ml,ALT:(7.8±2.7) U/ml] (P＜0.05).血清TNF-α、ICAM-1含量:IR组[TNF.α:(23.1±4.8) μg/L,ICAM-1:(34±9)μg/L]和Ket组[TNF-α:(19.1+5.8)μg/L,ICAM-1:(41±7) μg/L]均高于Sham组[TNF-α:(8.7±2.4) μg/L,ICAM-1:(13±5)μg/L](P＜0.05).而Ket组和IR组之间无统计学差异(P＞0.05).W/D比值:IR组(6.9±1.7)和Ket组(5.1±1.1)高于Sham组(3.7±0.7)(P＜0.05),IR组高于Ket组(P＜0.05).肺组织中TNF-α mRNA、ICAM-1 mRNA和NF-kb/P65含量:IR组[TNF-α mRNA:(2.91±0.49)μg/L,ICAM-1 mRNA:(2.39±0.58) μg/L,NF-kb/P65:(1.97±0.17) μg/L]高于Sham组[TNF-αmRNA:(1.75±0.29) μg/L,ICAM-1 mRNA:( 1.63±0.33) μg/L,NF-kb/P65:(1.06±0.24) μg/L]和Ket组[TNF-α mRNA:(2.19±0.52) μg/L,ICAM-1 mRNA:(1.78±0.28)μg/L,NF-kb/P65:(1.33±0.30μg/L](P＜0.05).Sham组和Ket组之间无统计学差异(p＞0.05).肺组织病理评分:Sham组低于IR组和Ket组(P＜0.05),Ket组低于IR组(P＜0.05).相关性:TNF-α mRNA与NF-kb/P65正相关,R=0.849(P＜0.05),ICAM-1 mRNA与NF-kb/P65正相关,R=0.639(P＜0.05).结论 10 mg/kg氯胺酮20 min前预处理对于全肝缺血/再灌注肺损伤有保护作用.     

Renal ischemia/reperfusion against nephrectomy for induction of acute lung injury in rats

Purpose: Acute kidney injury (AKI) induces acute lung injury (ALI) through releasing injurious mediators or impairing clearance of systemic factors. To determine the links between AKI and ALI, pulmonary and blood variables were evaluated following induction of AKI via different experimental models of bilateral renal ischemia/reperfusion (BIR: renal ischemia with uremia), unilateral renal ischemia/reperfusion (UIR: renal ischemia without uremia), bilateral nephrectomy (BNX: uremia without renal ischemia), and unilateral nephrectomy (UNX: without uremia and renal ischemia).

Methods: Ninety male Sprague–Dawley rats were divided into six groups. Animals had 1-h bilateral or 2-h unilateral renal ischemia followed by 24-h reperfusion in the BIR and UIR groups, respectively, and 24-h period following bilateral or unilateral nephrectomy in the BNX and UNX groups, respectively. There were also sham and control groups with and without sham-operation, respectively.

Results: Plasma malondialdehyde and nitric oxide were elevated by BIR more than UIR, but not changed by UNX and BNX. UIR slightly increased plasma creatinine, whereas BIR and BNX largely increased plasma creatinine, urea, K^+?and osmolality and decreased arterial HCO₃^?, pH, and CO₂. UNX and UIR did not affect lung, but BIR and BNX induced ALI with equal capillary leak and macrophages infiltration. However, there were more prominent lung edema and vascular congestion following BNX and more severe neutrophils infiltration and P_aO₂/F_iO₂ reduction following BIR.

Conclusion: Acutely accumulated systemic mediators following renal failure in the absence of kidneys vary from those due to combined renal failure with ischemic-reperfused kidneys and consequently they induce ALI with distinct characteristics.     

阿片类药物减轻急性缺血/再灌注损伤及相关机制

背景 缺血预处理对于器官缺血/再灌注损伤（ischemia/reperfusion injury,I/RI）具有强大的保护作用,但其临床应用受到时机以及伦理学的限制.近年来有研究发现阿片类药物预处理以及后处理对组织器官I/RI同样具有保护作用,其既不损伤器官又能产生与缺血预处理相同的效果,是更为可行的治疗措施. 目的 在将阿片类药物处理推广至临床应用前,仍需进行更多大规模的临床研究.拟就阿片类处理减轻I/RI的发展过程及其作用机制进行探讨. 内容 阿片类药物处理I/RI的几种方式及其机制. 趋向 阿片类药物处理比较其他损伤性处理方式更易操作,且对I/RI同样具有保护作用,有望成为日后治疗的热点之一.     

七氟醚对心肌缺血/再灌注损伤的临床研究进展

背景 七氟醚的心肌保护作用得到广泛关注,大量基础研究表明七氟醚对心肌缺血/再灌注损伤(myocardial ischemia/reperfusion injury,MI/RI)具有确切的保护作用.然而,临床中关于七氟醚具有心肌保护作用的结论尚未完全统一.目的 通过总结近年的研究进展对七氟醚的心肌保护作用进行阐述.内容 不同心脏手术及非心脏手术中七氟醚药物处理的心肌保护效果.趋向 今后仍需加强对七氟醚心肌保护作用的临床研究,为围手术期患者的心肌保护提供更为可靠的理论依据.     

针刺预处理对脑缺血/再灌注损伤的保护作用

针刺预处理的脑保护可能机制如下:减轻脑水肿和微血管损伤,增加脑血流量,影响缺血脑组织在病理形态学及超微结构改变,有利于维持细胞内外离子的稳态,对抗自由基损伤及脂质过氧化反应.并影响细胞因子、神经递质及脑细胞信号转导、凋亡调节基因等;针刺预处理对脑缺血/再灌注的保护效果表现为其穴位、刺激频率和刺激持续时间上的特异性.     

七氟醚对肺缺血／再灌注损伤的保护机制

背景七氟醚作为一种较理想的吸入麻醉药,被广泛应用于临床,实验表明七氟醚对肺缺血／再灌注损伤（ischemia／reperfusion injury,I／RI）具有保护作用。目的通过分析近年的研究总结七氟醚对肺I／RI的保护机制。内容七氟醚通过减轻肺通透性、抑制炎症反应、减轻脂质过氧化反应、抑制细胞凋亡、减轻细胞内钙离子超载等发挥肺I／RI的保护作用。趋势应进一步探讨七氟醚对肺的保护作用,加强对七氟醚的临床应用研究,为实际临床工作提供可靠的依据。     

甘氨酸和丙酮酸对于局部缺血再灌注后的全身性保护作用

目的 肠系膜上动脉缺血/再灌注可引起小肠局部损伤,甚至休克和心肺功能障碍。丙酮酸和甘氨酸已被证实对缺血再灌注损伤的局部组织器官有保护作用。本文研究其对小肠缺血再灌注之后全身血流动力学以及心肺功能等的影响。方法 采用雄性SD大鼠,麻醉后建立血流动力学监测,建立肠系膜上动脉缺血90 min、再灌注120 min的模型。24只大鼠随机分为4组：丙酮酸组（再灌注前给予丙酮酸50 mg/kg,n=6）;甘氨酸组（再灌注前给予甘氨酸20 mg/kg,n=6）;林格组（再灌注前给予林格氏液1 mL,n=6）;假手术对照组（n=6）。术中记录平均动脉压、心脏指数、肺动脉压等,并估计循环血管阻力。采集动脉血进行血气分析和心肌标志物检测。观察结束后处死大鼠,取小肠、心脏、肺脏、肝脏进行组织学观察。结果 丙酮酸和甘氨酸均能有效稳定血流动力学参数,维持较好的心功能。其中甘氨酸组复苏所需晶体体积显著少于对照组。丙酮酸、甘氨酸对代谢性酸中毒的抑制作用明显优于林格氏液（P<0.01）。甘氨酸组的小肠、肺、心、肝病理评分和中性粒细胞浸润明显低于林格组（P<0.01）,但仍高于假手术组（P<0.01）。丙酮酸组、甘氨酸组CKMB、肌钙蛋白I水平低于林格组,但仍高于假手术组（P<0.01）。结论 丙酮酸和甘氨酸能在严重的局部缺血再灌注之后稳定全身循环状态,改善休克的复苏效果,既可减轻局部组织器官的缺血再灌注损伤,又可保护心肺等器官的功能。     

电针对脑缺血/再灌注损伤的神经保护的研究进展

背景 中国针灸用于中风等神经系统疾病的治疗有悠久的历史和丰富的临床经验.电针是传统针灸与现代电学技术相结合的治疗方式,它对脑缺血/再灌注损伤(ischemia/reperfusion injury,I/RI)的病理演变有重要影响.目的 探讨电针的神经保护及其机制.内容 依照脑I/RI的病理生理机制,分析与总结电针对脑I/RI的保护作用及其机制. 趋向 电针在运用补充与替代疗法预防、治疗或辅助治疗脑I/RI方面有良好的发展前景.     

Hypoxia-inducible factor prolyl hydroxylase inhibitor roxadustat (FG-4592) protects against renal ischemia/reperfusion injury by inhibiting inflammation

Hypoxia-induced inflammation is the critical pathological feature of acute kidney injury (AKI). Activation of hypoxia-inducible factor (HIF) signaling is considered as a central mechanism of body adapting to hypoxia. Hypoxia-inducible factor prolyl hydroxylase inhibitor FG-4592 (Roxadustat) is a first-in-class HIF stabilizer for the treatment of patients with renal anemia. The current study aimed to investigate whether FG-4592 could protect against ischemia/reperfusion (I/R)-induced kidney injury via inhibiting inflammation. Here, efficacy of FG-4592 was evaluated in a mice model of I/R-induced AKI. Interestingly, improved renal function and renal tubular injuries, combined with reduced kidney injury molecule-1 were observed in the mice with FG-4592 administration. Meanwhile, inflammation responses in FG-4592-treated mice were also strikingly attenuated, as evidenced by the decreased infiltration of macrophages and neutrophils and down-regulated expression of inflammatory cytokines. In vitro, FG-4592 treatment significantly protected the tubular epithelial cells against hypoxia-induced injury, with suppressed inflammation and cell injuries. In summary, FG-4592 treatment could protect against the I/R-induced kidney injury possibly through diminishing tubular cells injuries and suppression of sequence inflammatory responses. Thus, our findings definitely offered a clinical potential approach in treating AKI.     

丙泊酚对全脑缺血/再灌注损伤大鼠保护作用研究

目的探讨丙白酚对大鼠全脑缺血/再灌注损伤（ischemia/reperfusion injury,I/RI）的保护作用。方法65只Wistar雄性大鼠采用完全随机法分为5组：假手术组（S组）、缺血/再灌注(ischemia/reperfusion,I/R)组(I/R)组、丙泊酚组1(P1)、丙泊酚组2(P2)、丙泊酚组...     

不同浓度左旋卡尼汀对离体兔缺血/再灌注心脏功能的保护作用

目的 观察不同浓度左旋卡尼汀(L-carnitine,L-CN)预处理对高钾停跳离体兔缺血/再灌注心脏功能的保护作用.方法 采用离体兔心Langendorff灌注实验模型,离体兔心24只随机等分成缺血/再灌注组、L-CN 2.5 mmol/L、L-CN 5.0 mmol/L、L-CN 10mmol/L 4组(n=6).缺血/再灌注损伤组:灌注K-H液25 min,(兔心)4℃标准St.Thomas停搏液(K~+16 mmol/L)至心脏停跳,45 min后恢复K-H液灌注20 min;不同浓度L-CN组:灌注K-H液10 min,再予不同浓度的L-CN续灌15 min,余步骤同缺血/再權注组.观察灌注过程中各组的血流动力学指标.心肌TTC染色测定缺血面积和梗死面积百分比.结果 再灌注后浓度5.0mmol/L和10.0 mmol/L的L-CN预处理的离体兔心心功能的恢复率均明显高于对照组(P＜0.05);其心肌存活面积百分比高于对照组(P＜0.05).结论 L-CN预处理对高钾停跳离体兔缺血/再灌注心脏具有较好的心功能保护作用.     

Inhibition of nitric oxide synthase reduces renal ischemia/reperfusion injury

BACKGROUND: The role of nitric oxide (NO) production because of inducible nitric oxide synthase (iNOS) in the pathogenesis of renal ischemia/reperfusion (I/R) injury is unclear. In this study the roles of both iNOS and NO were characterized in a rat model of renal I/R injury. In addition, the effect of iNOS inhibition on renal function was evaluated. METHODS: Sprague-Dawley rats underwent 45 min of left renal ischemia and contralateral nephrectomy followed by various periods of reperfusion and renal function analysis [plasma creatinine, fractional excretion of sodium (FENa), creatinine clearance (CrCl), and measurement of plasma and urine NO levels]. In addition, the effect of treatment with 1400W, a highly selective iNOS inhibitor, was evaluated. RESULTS: Renal dysfunction peaked at 48 h after reperfusion and immunohistochemistry studies revealed iNOS expression in the vasculature (3 h) and renal tubules (48 h) after reperfusion. Renal function improved significantly in treated animals compared to controls [creatinine of 1.1 v. 1.9 mg/dl (P < 0.05) and CrCl of 0.54 v. 0.31 ml/min (P < 0.05), respectively]. In addition, FENa was decreased by 50%, plasma NO levels were significantly lower (32.7 v. 45.7 micromol/L, P < 0.01), and deposition of nitrotyosine in the tubules of treated rats was less than in control animals. CONCLUSIONS: These data support the hypothesis that iNOS and NO are involved in the pathogenesis of renal I/R injury and suggests that use of iNOS inhibitors may be a valuable therapeutic strategy clinical situations where renal I/R may be prevalent.     

心磷脂与缺血/再灌注损伤

心磷脂（CL）是维持线粒体能量代谢所必需的一种磷脂，参与了众多重要生理过程。此文对CL的结构、合成和转化；在维持线粒体正常功能中的作用；缺血／再灌注（I／R）损伤中的改变以及和线粒体功能的关系等作了逐一阐述，说明CL与I／R损伤导致的细胞死亡关系密切，CL量或性质的改变在细胞凋亡中处于中心地位。     

异丙酚预处理对大鼠离体心脏缺血-再灌注损伤的影响

目的 探讨异丙酚预处理对心肌缺血-再灌注(I-R)损伤的作用及其机制。方法 成年雄性 SD 大鼠18只，随机分为对照组(C组)、I-R 组、50μmol/L 异丙酚预处理组(P组)，每组6只。建立Langendorff 离体心脏灌流模型，平衡35min 后 I-R 组和 P 组均停灌30min，然后复灌120min。其中 P 组停灌前用含50μmol/L 异丙酚的 K-H 液灌流10min，并用无异丙酚的 K-H 液冲洗10min。C 组不停灌，也不用异丙酚处理。灌流结束后，制备心肌组织匀浆，测定 NO 含量、总 NOS 及超氧化物歧化酶(SOD)活性，用免疫组化 SABC 染色检测诱导型 NOS(iNOS)蛋白与血红素氧化酶-1(HO-1)蛋白表达水平，同时行光镜及透射电镜观察。结果病理学显示 C 组正常，I-R 组心肌组织严重损伤，P 组轻度损伤；与C 组相比，I-R 组和 P 组 iNOS、HO-1蛋白表达量和 iNOS 活性均升高，cNOS 活性均降低(P<0.05或0.01)；I-R 组总 NOS 活性和 NO 含量、Cu.Zn-SOD、Mn-SOD 和总 SOD 活性均降低(P<0.05或0.01)，但P 组无变化(P>0.05)。与 I-R 组比较，P 组除 iNOS 活性不变外，其余指标均升高(P<0.05或0.01)。结论 异丙酚预处理对心肌 I-R 损伤具有保护作用，其机制在于抑制或清除氧自由基以降低氧化应激水平，并通过恢复 cNOS 活性而增加 NO 的含量。     

Role of leukotrienes on hepatic ischemia/reperfusion injury in rats

BACKGROUND: Leukotrienes (LT), composed of cysteinyl LT (cLT; LTC(4), LTD(4), and LTE(4)) and LTB(4), are potent lipid mediators enhancing the vascular permeability and recruitment of neutrophils, which are common features of hepatic ischemia/reperfusion (I/R) injury. The aim of this study was to investigate whether LT can mediate the liver and lung injuries following hepatic I/R. MATERIALS AND METHODS: Sprague-Dawley rats were subjected to 90 min of partial hepatic ischemia followed by 3, 12, and 24 h of reperfusion. In the hepatic and pulmonary tissues, LT content and the mRNA expression of LT-synthesis enzymes, 5-lypoxygenase (5-LO), LTC(4) synthase (LTC(4)-S), and LTA(4) hydrolase (LTA(4)-H) were measured. Tissue injuries were assessed by plasma ALT, histological examination, and wet-to-dry tissue weight ratios. RESULTS: The cLT content in the hepatic tissue after 12 and 24 h reperfusion was increased 4- to 5-fold compared to controls and this was accompanied by the enhancement of hepatic edema and plasma ALT elevation. There were no significant changes in the mRNA expression of LT-synthesis enzymes in both tissues. LTB(4) levels were not increased despite a significant neutrophil infiltration in both tissues. CONCLUSIONS: These data suggest that cLT are generated in the liver during the reperfusion period and may contribute to the development of hepatic edema and exert cytotoxicity. Factors other than LTB(4) may contribute to neutrophil infiltration.     

肢体缺血预处理减轻肝缺血/再灌注损伤的研究进展

背景 肝缺血/再灌注损伤(hepatic ischemia/reperfusion injury,HI/RI)是肝外科手术及肝移植中常见的病理生理现象,是术后肝功能衰竭和移植物无功能的主要原因.研究表明肢体缺血预处理(limb ischemia preconditioning,LIPC)可减轻HI/RI,具体机制仍不清楚.目的 通过综述LIPC减轻HI/R1的可能机制,为临床减轻HI/RI提供新的思路.内容 介绍HI/RI机制及LIPC减轻HI/RI的可能作用机制.趋向 LIPC作为减轻HI/RI的措施具有重大的临床应用价值.     

异丙酚对大鼠离体心脏缺血/再灌注损伤的保护作用

目的 观察异丙酚对大鼠离体心脏缺血／再灌注损伤时左右心室功能的影响。方法 雄性SD大鼠16只分成对照组和实验组,行Langendorff灌注后,刺激器控制心率在348次／min,均经历平衡期25min、全心缺血期30min和再灌注期40min。实验组在平衡的后半期持续灌注含有异丙酚6μg/ml的灌注液10min。灌注期间通过心室内的乳胶水囊经换能器连于MacLab Instrument和计算机,观察两组左右心室等容收缩时压力和速度指标的变化。定时测量冠脉流量。再灌注末取左室心肌组织测定心肌SOD活性。结果 再灌注后,实验组的LVDP和RVDP明显上升,而LVEDP昨RVEDP显著降低;同时左右心室dp/dtmax较对照组显著增高,而dp/dtmin显著降低。再灌注期实验组的冠脉流量增加。再灌期末实验组心肌组织SOD活性较对照组显著升高。结论 缺血前灌注6μg/ml异丙酚对大鼠离体心脏缺血再灌注损伤时左右室的舒缩功能和心肌的内在收缩性具有一定的保护作用。异丙酚增加了再灌注期的冠脉流量,提高了心肌组织的SOD活性。     

瘦素在肝缺血/再灌注致肾损伤中作用的研究

目的：研究瘦素（Leptin）在肝缺血/再灌注（I/R）后肾组织中的表达变化,探讨其与肝I/R介导的肾损伤的关系。方法：建立大鼠70%肝I/R模型,设立假手术和缺血60min后再灌注60、150、240、360min组,观察肾脏的病理学变化,检测各组血清尿酸、总抗氧化能力,肾Leptin蛋白及其mRNA表达的变化。结果：与假手术组比较,缺血60min/再灌注150min及再灌注240min组血清尿酸显著升高,以再灌注240min升高最为显著;再灌注240min和360min组血清总抗氧化能力显著升高,以再灌注240min升高最为显著;再灌注150、240和360min组肾Leptin蛋白表达显著升高,再灌注60、240、360min组肾LeptinmRNA表达显著升高,而再灌注150min组LeptinmRNA显著降低。病理学观察提示肝I/R早期的肾损伤较重而后期显著减轻。结论：Leptin在肝I/R后肾组织内的表达变化与肾损伤密切相关,提示它可能作为一种保护因子对抗肝I/R介导的肾损伤。     

Protective effects of vitamin E against liver damage caused by renal ischemia reperfusion

Abstract

Recent studies have reported that remote organs are affected by renal ischemia reperfusion (IR). The present study investigates the role of vitamin E on the liver damage after renal IR. First, male mice were subjected to three groups (n?=?9): 1) sham-operated, (2) renal IR (45?min ischemia), (3) renal IR?+?Vitamin E (150?mg/kg trough feeding tube for 28?d). After 24?h of reperfusion, animal were anesthetized for sample collections. Liver tissues malondialdehyde (MDA) increased and total glutathione (GSH) concentration decreased in the IR group compared to the sham group. Vitamin E consumption diminished the IR-induced increase in plasma AST and ALT. In addition, Vitamin E inhibited the IR-induced decrease in GSH activity and diminished IR-induced increase in MDA concentration. These findings showed that vitamin E consumption partly inhibited the IR-induced liver damage.