粉防已碱对急性缺血性肾损伤细胞凋亡的影响

目的：探讨粉防已碱在急性缺血性肾损伤中的作用及与细胞凋亡的关系。方法：在钳夹册侧肾蒂４５ｍｉｎ致大鼠急性缺生肾损伤模型的基础上，采用肾组切片ＨＥ染色、肾ＤＮＡ片分析及原位末端转移酶标记法等技术，定性、定量分析了急性缺血性肾损伤时肾小管上皮细胞的凋亡现象。结果：急性缺血性肾损伤时，肾小管皮皮细胞的凋亡现象明显啬粉防已碱对急性缺血性肾损伤具有保护作用，能够明显降低受损肾小雕恨水平。结论急性缺血性肾损伤     

粉防己碱用于大鼠急性缺血性肾损伤的实验研究

目的 探讨粉防己碱在急性缺血性肾损伤中的保护性作用机制。方法 采用动脉夹钳夹大鼠双侧肾蒂，造成双肾完全缺血４５分钟的动物模型，地粉防己碱用药已未用药组大鼠不同再灌注时间以及肾组织不同部位的肾小管上皮细胞损伤情况进行观察。结果 在肾组织皮质区与外髓区缺血再灌注后的各时相内，用药组肾小管的损伤程度均明显低于未用药组；两组肾小管损伤程度在内髓区任何血再灌注时相内均无显著性差异     

粉防己碱用于大鼠急性缺血性肾损伤的实验观察

目的探讨粉防己碱在急性缺血性肾损伤中的保护性作用机制。方法采用动脉夹钳夹大鼠双侧肾蒂,造成双肾完全缺血４５分钟的动物模型,对粉防己碱用药及未用药组大鼠不同再灌注时间以及肾组织不同部位的肾小管上皮细胞损伤情况进行观察。结果在肾组织皮质区与外髓区缺血再灌注后的各时相内,用药组肾小管的损伤程度均明显低于未用药组（Ｐ＜０００１）;两组肾小管损伤程度在内髓区任何血再灌注时相内均无显著性差异（Ｐ＞００５）;两组均以外髓处肾小管形态学变化最为明显,其次为皮质、内髓的肾小管形态学变化最不明显。结论粉防己碱可减轻缺血再灌注后肾小管的损伤程度,它的主要作用部位可能在肾脏的皮质与外髓区域。     

黄芪当归合剂对大鼠缺血性急性肾损伤的保护研究

目的:探讨黄芪当归合剂对实验性缺血性肾损伤大鼠肾小管上皮细胞凋亡的保护作用.方法:建立大鼠实验性缺血性急性肾损伤模型,在缺血30 min再灌注不同时间点检测血尿素氮(BUN)、血肌酐(SCr)和尿液中N-乙酰-β-D-氨基葡萄糖酐酶(NAG).同时取肾组织,苏木素-伊红(HE)染色,光镜下观察细胞形态学变化.免疫组织化学方法检测Bcl-2和Bax基因的蛋白表达,观察黄芪当归合剂对上述表达的影响.结果:缺血性急性肾损伤时肾脏存在明显的细胞凋亡;Bcl-2和Bax基因的蛋白表达主要在近曲肾小管和远曲肾小管,肾小球很少;肾脏缺血性损伤时Bcl-2基因表达增加,Bax基因表达中量增加,Bcl-2/Bax比率升高.与缺血/再灌注组比较,黄芪当归合剂组Bax表达明显增加,Bcl-2/Bax比率降低,肾脏损伤亦减轻.结论:黄芪当归合剂对急性肾损伤具有显著的保护作用,其机制可能与其降低Bcl-2/Bax比率有关.     

小剂量环孢霉素A抑制大鼠缺血性急性肾衰竭中肾小管上皮细胞线粒体通透性转运

目的研究小剂最环孢霉素A(CsA)对大鼠缺血性急性肾衰竭诱导的肾小管上皮细胞线粒体通透性转运的影响,探讨其抑制肾小管上皮细胞凋亡的作用机制。方法Wistar大鼠双侧肾动脉夹闭30min诱导缺血性急性肾衰竭。再灌注18h后留取肾组织及血液标本。比色法测定血清肌酐(SCr)浓度,原位末端标记(TUNEL)法检测肾小管上皮细胞凋亡情况,Westernblot测定肾组织中胞浆细胞色素C、caspase-3、9蛋白质表达。结果肾脏缺血30min／再灌注18h后大鼠SCr明显升高[(106．9±19．4)μmol／Lvs(56．5±7．1)μmol／L,P<0．05],肾小管上皮细胞凋亡数目显著增加[(20．14±3．70)％vs(0．99±0．17)％,P<0．05],肾组织胞浆细胞色素c、caspase-3、9表达增加(P<0．05);CsA能显著降低SCr[(87．5±18．5)μmol／L],减轻肾小管上皮细胞凋亡[(14．61±3．39)％],下调胞浆细胞色素C、caspase-3、9表达(P<0．05)。结论小剂量CsA能抑制大鼠缺血性急性肾衰竭引起的线粒体通透性转运,从而减轻肾小管上皮细胞凋亡,保护肾功能。     

骨髓干细胞移植对急性缺血性肾损伤大鼠肾小管细胞活性的影响

目的观察和分析骨髓干细胞(BMSCs)移植对大鼠急性缺血性肾损伤后肾小管上皮细胞坏死、变性及增殖的影响。方法 Percoll密度梯度离心法分离获取BMSCs。制作大鼠急性缺血性肾损伤模型,通过下腔静脉进行BMSCs移植。分别于缺血再灌注后24h、48h、7d、14d获取肾脏标本,HE染色作肾组织学观察,免疫组织化学染色检测增殖细胞核抗原(PCNA)的表达。结果缺血再灌注后24h、48h,BMSCs移植组肾小管上皮细胞未见坏死及明显变性,而对照组细胞坏死及变性明显;缺血再灌注后7d、14d,BMSCs移植组和对照组肾小管上皮均无细胞坏死,但对照组可见部分细胞胞浆肿胀及间质内少许红细胞;BMSCs移植组较对照组肾小管上皮PCNA阳性细胞数增多,组间差异具统计学意义。结论 BMSCs移植可减少急性缺血性肾损伤的肾小管上皮细胞变性、坏死,而促进肾小管上皮细胞的增殖。     

甘油致大鼠急性肾功能衰竭肾小管细胞凋亡的动态实验观察

目的：观察肾小管上皮细胞凋亡在甘油致急性肾功能衰竭大鼠中的变化。方法：采用肌注甘油法复制急性肾功能衰竭大鼠模型，分12、72h与8d时点取材检测检测血浆BUN、SCr、肾组织脂质过氧化物（LPO）以及进行肾组织凋亡细胞TUNEL染色。结果：急性肾功能衰竭大鼠12、72h两时点BUN、SCr、肾组织LPO水平均明显升高，第8d基本恢复正常，但肾小管上皮细胞凋亡持续存在。结论：细胞凋亡以角色转换的方式存在于急性肾衰的损伤功能障碍与修复各个阶段，发挥不同意义的生物学作用。     

低氧诱导因子1α基因修饰脂肪干细胞修复小鼠急性肾损伤

背景：干细胞移植为肾损伤的治疗提供了一个新的途径,治疗基因转染干细胞可增强对疾病的治疗效果。目的：探讨低氧诱导因子1α基因修饰的脂肪源性干细胞移植对急性肾损伤小鼠肾脏结构和功能的影响。方法：连续2d向BALB/C裸鼠腹腔注射10mg/kg顺铂诱导急性肾损伤小鼠模型。造模24h后经小鼠尾静脉注射含1×105个脂肪源性干细胞或转染低氧诱导因子1α的脂肪源性干细胞的细胞悬液,3d后留取小鼠血液及肾组织标本进行实验。以注射200μL生理盐水的急性肾损伤小鼠作为模型对照,以正常小鼠作为正常对照。结果与结论：脂肪源性干细胞干预后急性肾损伤小鼠血清肌酐、尿素氮水平降低,肾组织病理改变及肾小管上皮细胞的凋亡病变减轻,肾组织炎症因子RANTES、肿瘤坏死因子α表达降低,白细胞介素10表达升高;其中低氧诱导因子1α基因修饰的脂肪源性干细胞对肾组织细胞凋亡及炎症因子表达作用更明显。免疫荧光染色可见移植的脂肪源性干细胞的存活,但未见其向肾小管上皮细胞转化。结果表明脂肪源性干细胞移植可改善急性肾损伤小鼠的肾脏结构和功能,经低氧诱导因子1α基因修饰后的脂肪源性干细胞作用更显著。     

TNFα-在小鼠叶酸诱导肾病中的致病作用及其机理研究

目的研究TNF-α在小鼠叶酸诱导肾病中的致病作用及其机制。方法建立小鼠叶酸诱导肾病模型,运用抗TNF-α多克隆抗体及对照抗体干预治疗,检测小鼠血清以及肾组织中TNF-α水平,肾小管上皮细胞凋亡情况以及凋亡相关蛋白的表达水平。结果在CD1小鼠叶酸诱导肾病模型中,尿素氮水平显著升高,肾小管上皮细胞坏死和凋亡增加,小鼠血清以及肾组织中TNF-α水平显著升高,肾皮质组织中Bcl-xL表达水平显著下降,运用抗TNF-α多克隆抗体干预治疗可保持Bcl-xL在肾组织中的表达水平,减少肾小管上皮细胞凋亡,有效减轻小鼠肾功能损害。结论TNF-α在小鼠叶酸诱导肾病发病机制中具有重要作用,阻断TNF-α是治疗急性肾衰的一种潜在有效手段。     

骨髓间充质干细胞在肾缺血-再灌注损伤早期的抗凋亡作用

目的 观察骨髓间充质干细胞(mesenchymal stem cells,MSCs)自体移植对兔肾缺血-再灌注(ischemia reperfusion,I/R)损伤早期的治疗作用及其对肾小管上皮细胞凋亡的影响.方法 骨穿刺抽取新西兰大耳白兔股骨骨髓,分离、培养、扩增MSCs.30只新西兰大耳白兔随机分为移植组、对照组和假手术组,每组10只.移植组夹闭双肾动脉90 min,再灌注后经颈静脉移植BrdU标记的自体MSC8.对照组夹闭双肾动脉90 min,再灌注后经颈静脉注入等量生理盐水.假手术组假手术后经颈静脉移植Brdu标记的自体MSCs.肾I/R后48 h处死兔,比较兔肾功能和肾组织损伤,免疫组化法检测肾组织MSCs来源细胞,TUNEL法检测肾小管上皮细胞凋亡.用SPSS 13.0统计软件进行统计学分析,肾功能和肾小管细胞凋亡比较用ANOVA单因素方差分析;肾损伤指数比较用非参数的Kruskalwallis检验,以P<0.05为差异有统计学意义.结果 移植组较对照组肾功能明显改善(24 h,BUN:F=7.483,Scr:F=15.091;48 h,BUN:F=17.741,Scr:F=61.865;P<0.05),肾损伤明显减轻(F=12.658,P<0.01).移植组肾小管上皮细胞凋亡明显减少(F=135.495,P<0.01),且差异均具有统计学意义(P<0.05).I/R后48 h,移植组肾组织内可见少量BrdU阳性细胞.结论 MSCs自体移植对急性肾I/R损伤有治疗作用,其可能机制是通过减少肾小管上皮细胞凋亡来减轻肾I/R损伤早期的肾损害.     

Pathophysiology of acute renal failure at the cellular level

The influence of inflammation on post-ischemic acute renal failure (ARF) has only recently be appreciated. In this review we therefore discuss the cellular events occurring in ARF with special emphasis on the impact of inflammatory processes on the pathogenesis of ARF. Furthermore, the spectrum of injury leading to sublethal or lethal cell damage and the time course, occurrence and regulation of the two distinct forms of cell death, necrosis and apoptosis will be described extensively. Especially apoptosis and its regulation has been studied only marginally in the setting of ischemic ARF. This overview is mainly focused on tubular cell injury since tubular epithelial cells are the major victims of ischemia whereas cells inside the glomerular tuft show only little pathology. The models of tubular injury described in this paper are ranging from primary cultures of isolated human tubular epithelial cells to experimental ischemic renal failure in rats, and to clinical settings of human ischemic ARF. The cellular events highlighted in this review are the influence of the expression of cellular adhesion molecules on the pathophysiology of ARF, and the regulation and time course of apoptosis. Examples of these processes are being illustrated by figures exhibiting morphology and immunohistochemistry of cell proliferation and cell death regulatory proteins.     

Lésions d’ischémie-reperfusion rénale

Ischemia-reperfusion-induced renal injury due to profound decrease of renal blood flow followed by restoration of renal perfusion is frequent in critically ill patients. Ischemic-induced microcirculatory dysfunction and perfusion defects persist after reperfusion leading to extension of initial renal damage, renal fibrosis, and acute or chronic renal failure. Renal ischemia-reperfusion should not be regarded as a sole ischemic injury with acute tubular necrosis but involves renal inflammation with infiltration of immune cells with tubular necrosis and apoptosis. Despite numerous promising pre-clinical therapeutic interventions protecting the kidney from ischemic injury, such strategies have been mostly unsuccessful in the clinical setting. Multiplicity of factors involved with complexes mechanisms of injury in most clinical scenarios may explain such discrepancy.     

急性肾缺血再灌注大鼠肾细胞游离钙水平与细胞凋亡的研究

目的观察缺血再灌注损伤对肾细胞游离钙([Ca2+]i)水平和细胞凋亡的影响。方法采用摘除左肾,钳夹大鼠右侧肾蒂,建立急性缺血再灌注肾损伤模型,应用Fura-2/AM荧光指示剂测定缺血再灌注大鼠肾细胞[Ca2+]i水平,流式细胞术检测肾细胞凋亡率。结果缺血再灌注不同时期肾细胞呈现不同程度Ca2+超载,与对照组相比差异显著(P0.01);肾细胞凋亡率增高,与对照组相比差异显著(P0.05、P0.01),有正相关趋势。结论缺血再灌注不同时期肾细胞游离钙([Ca2+]i)水平增高,并与肾细胞凋亡率有正相关趋势,再灌注时间与肾细胞Ca2+超载呈正相关,提示再灌注损伤在加重细胞钙超载同时增加了肾组织细胞凋亡,可能是再灌注损伤肾功能障碍的重要原因。     

CSF-1 signals directly to renal tubular epithelial cells to mediate repair in mice

Tubular damage following ischemic renal injury is often reversible, and tubular epithelial cell (TEC) proliferation is a hallmark of tubular repair. Macrophages have been implicated in tissue repair, and CSF-1, the principal macrophage growth factor, is expressed by TECs. We therefore tested the hypothesis that CSF-1 is central to tubular repair using an acute renal injury and repair model, ischemia/reperfusion (I/R). Mice injected with CSF-1 following I/R exhibited hastened healing, as evidenced by decreased tubular pathology, reduced fibrosis, and improved renal function. Notably, CSF-1 treatment increased TEC proliferation and reduced TEC apoptosis. Moreover, administration of a CSF-1 receptor–specific (CSF-1R–specific) antibody after I/R increased tubular pathology and fibrosis, suppressed TEC proliferation, and heightened TEC apoptosis. To determine the contribution of macrophages to CSF-1–dependent renal repair, we assessed the effect of CSF-1 on I/R in mice in which CD11b⁺ cells were genetically ablated and determined that macrophages only partially accounted for CSF-1–dependent tubular repair. We found that TECs expressed the CSF-1R and that this receptor was upregulated and coexpressed with CSF-1 in TECs following renal injury in mice and humans. Furthermore, signaling via the CSF-1R stimulated proliferation and reduced apoptosis in human and mouse TECs. Taken together, these data suggest that CSF-1 mediates renal repair by both a macrophage-dependent mechanism and direct autocrine/paracrine action on TECs.     

粉防己碱对人结肠癌细胞株HT-29增殖与凋亡的影响

目的:通过观察粉防己碱对人结肠癌细胞株HT-29增殖与凋亡的影响,初步探讨粉防己碱对结肠癌的体外抗肿瘤效应。方法:采用MTT比色法观察粉防己碱对HT-29细胞的增殖抑制效应,利用细胞DNA琼脂糖凝胶电泳及细胞凋亡荧光染色法检测粉防己碱诱导肿瘤细胞凋亡的作用,以免疫细胞化学法检测粉防己碱对Bcl-2和BAX表达水平的影响。结果:MTT比色法显示粉防己碱对人结肠癌细胞株HT-29增殖有抑制作用,其抑制效应具有剂量依赖的特点,细胞凋亡荧光染色法、琼脂糖凝胶电泳表明粉防己碱可诱导HT-29细胞凋亡,免疫细胞化学法显示粉防己碱上调BAX基因表达,下调Bcl-2基因表达。结论:粉防己碱对人结肠癌细胞株HT-29增殖的抑制效应具有剂量依赖性,并可诱导细胞凋亡,其抗肿瘤效应可能与凋亡相关基因表达的调控有关。     

Regulation of renal tubular cell apoptosis and proliferation after ischemic injury to a solitary kidney.

The time course and regulation of apoptosis and cellular regeneration after 30 minutes of acute ischemic injury to a single kidney was elucidated in rats at five time points over 20 weeks. The fraction of apoptotic cells was most prominent at 1 day after the insult in the distal tubule (8% +/- 4% vs 0% +/- 0%, acute renal failure [ARF] vs sham, respectively) and was still elevated at 7 days (2% +/- 2% vs 0% +/- 0%). At that time, the whole kidney mRNA expression of the apoptosis inhibitory genes bcl-xL and bcl-2, as well as that of the apoptosis promotor bax, was significantly reduced. Immunohistochemistry of kidney specimen showed suppression of bcl-2 in the distal tubule but up-regulation in the proximal tubule, whereas bax protein was more strongly expressed in the distal tubule. Cellular proliferation started at day 1 and continued over the following 20 weeks, leading to severe tubular dilation and kidney failure. These data indicate that differential regulation of bcl-2 family members contributes to the early apoptotic clearance of lethally injured tubular epithelial cells after ischemic injury to a solitary kidney.