Necrostatin-1对大鼠慢性心肌缺血损伤的保护作用

目的观察Necrostatin-1（Nec-1）对大鼠慢性心肌缺血后心功能和心肌反应性纤维化的影响。方法成年雄性SD大鼠被随机分为Nec-1处理组（7例）、溶剂对照组（例）和伪手术组（5例）。通过结扎冠状动脉左前降支建立心肌缺血模型，并于结扎的同时，给予大鼠尾静脉Nec-1（0．6mg／kg）或相应溶剂对照。在缺血2周后，观察左心室功能的改变，并用Masson氏染色法观察心肌反应性纤维化后心肌反应性纤维化的程度并测定相应的心肌梗死面积。结果应用Nec-1后与溶剂对照组比较，各项心功能指标如左心室收缩压（LVSP）、左心室舒张末压（LVEDP）、最大收缩速率（＋dp／dtmax）以及最大舒张速率（-dp／dtmax）均有明显改善；心肌反应性纤维化及心梗面积也显著减少[（3．5±1．0）％比（13．2±0．5）％，P〈0．01）]。结论Nec—1可以明显地抑制慢性心肌缺血大鼠的心肌反应性纤维化并改善心功能，具有显著的心肌保护作用。     

吡咯列酮对雨蛙肽诱导急性胰腺炎氧化应激过程的作用

目的 探讨过氧化物酶体增殖物激活受体(PPAR)γ激动剂吡咯列酮在雨蛙肽诱导大鼠急性胰腺炎中对氧化应激产物的影响及保护作用.方法 30只雄性SD大鼠随机分为对照组、雨蛙肽+不同剂量吡咯列酮组、雨蛙肽组、雨蛙肽+吡咯列酮+GW9662组.每组6只.急性胰腺炎造模30 min后处死大鼠,光镜下观察胰腺组织病理学变化,测定各组大鼠胰腺组织质量与体重比,比色法检测胰腺组织髓过氧化物酶(MPO)活性、丙二醛(MDA)和一氧化氮合酶(NOS)及组织诱导型一氧化氮合酶(iNOS)含量.结果 与对照组比较,雨蛙肽组胰腺组织水肿严重胰腺净重/体重(0.0072比0.0042)],MPO活性、MDA、NOS及iNOS含量升高(P＜0.01).与雨蛙肽组比较,吡咯列酮20 mg/kg及40 mg/kg组胰腺损伤减轻,胰腺净重/体重、MPO活性、MDA和NOS及iNOS含量降低(P＜0.05);与吡咯列酮40 mg/kg组比较,PPARγ拮抗剂GW9662逆转了吡咯列酮的保护作用(P＜0.05).结论 在雨蛙肽诱导的大鼠急性胰腺炎发病中,胰腺腺泡细胞的氧化应激损伤起了重要的作用,PPARγ激动剂吡咯列酮预先干预,通过降低氧化应激过程,对雨蛙肽诱导的大鼠急性胰腺炎有一定的保护作用.     

表皮生长因子对雨蛙肽联合应激诱导的大鼠急性出血性胰腺炎的保护作用

表皮生长因子(EGF)是参与细胞增殖、成熟和再生的主要因子。目前已证实其对胃肠道黏膜具有保护作用,能促进溃疡愈合,但是罕见关于EGF在急性出血性胰腺炎中作用的报道。目的:观察外源性EGF对雨蛙肽联合应激诱导的大鼠急性出血性胰腺炎的保护作用。方法:予雄性Sprague鄄Dawley大鼠腹腔内注射雨蛙肽(40μg/kg,两次注射间隔1h)联合水浸束缚应激(第一次注射雨蛙肽后开始,持续5h)诱导急性出血性胰腺炎。EGF治疗组第一次注射雨蛙肽之前0.5h和之后2.5h,分别皮下注射EGF1、10或30μg/kg。观察各组动物胰腺炎生化、病理学等指标的变化。结果:制模开始后12h,对照组的胰腺湿重为4.24g/kg±0.68g/kg,血清淀粉酶含量为4325U/L±822U/L,胰腺组织DNA和淀粉酶含量分别为1577μg/g±433μg/g和21.39U/mg蛋白±6.83U/mg蛋白,各病理学指标评分均为0。胰腺炎组的胰腺湿重(10.49g/kg±1.87g/kg)和血清淀粉酶含量(24433U/L±16751U/L)较对照组显著增高(P<0.01),胰腺组织DNA(561μg/g±278μg/g)和淀粉酶含量(16.95U/mg蛋白±5.01U/mg蛋白)则降低,病理学评分显著增高(P<0.01)。10μg/kgEGF能显著降低胰腺湿重(6.47g/kg±2.64g/kg,P<0.01)和血清淀粉酶含量(9010U/L±3983U/L,P<0.05),提高胰腺组织淀粉酶含量(23.92U/mg蛋白±8.58U     

miR-181a-5p靶向PIAS1对雨蛙肽诱导的急性胰腺炎腺泡细胞损伤的影响

背景急性胰腺炎(acute pancreatitis, AP)引起的急性炎症对人们健康的危害性极大,严重时会危及生命.其发病机制复杂,尚未完全清楚,研究发现miRNA参与了AP的发病过程.研究发现miR-181a-5p可抑制癌细胞迁移、侵袭和血管生成; miR-181a-5p还能抑制胃癌细胞增殖、侵袭,转移和上皮间充质转化.抑制miR-181a-5p表达可通过负向靶向INPP5A抑制细胞增殖和侵袭,增强宫颈癌细胞凋亡. miR-181a可抑制胰腺癌细胞系的生长、减少迁移,增加凋亡.但miR-181a-5p在AP的增殖凋亡中的影响及作用机制尚不清楚.目的研究miR-181a-5p对AP腺泡细胞损伤的影响及潜在的作用机制.方法用100nmol/L的雨蛙肽处理大鼠胰腺腺泡AR42J和MPC-83构建AP模型,设置Con组、Caerulein组、miR-NC组(转染miR-NC)、miR-181a-5p组(转染miR-181a-5p mimics)、anti-miR-NC组(转染antimiR-NC)、anti-miR-181a-5p组(转染anti-miR-181a-5p)、Caerulein+anti-miR-NC组(转染anti-miR-NC后进行Caerulein处理)、Caerulein+anti-miR-181a-5p组(转染anti-miR-181a-5p后进行Caerulein处)、Caerulein+pcDNA组(转染pcDNA后进行Caerulein处理)、Caerulein+pcDNA-PIAS1组(转染pcDNA-PIAS1后进行Caerulein处理)、Caerulein+anti-miR-181a-5p+si-NC组(anti-miR-181a-5p和si-NC共转染后进行Caerulein处理)、Caerulein+anti-miR-181a-5p+siPIAS1组(anti-miR-181a-5p和si-PIAS1共转染后进行Caerulein处理),用脂质体法转染至AR42J和MPC-83细胞.酶联免疫吸附试验法检测雨蛙肽处理AR42J和MPC-83细胞的TNF-α和IL-6的表达;qRT-PCR检测AR42J和MPC-83细胞中miR-181a-5p、PIAS1mRNA的表达水平; Western Blot检测蛋白表达;流式细胞术检测细胞凋亡;双荧光素酶报告基因检测实验检测荧光活性.结果雨蛙肽处理AR42J和MPC-83细胞后, TNF-α和IL-6的表达显著升高; miR-181a-5p的表达水平显著升高;PIAS1 mRNA和蛋白的表达水平显著降低. miR-181a-5p抑制表达和PIAS1过表达抑制TNF-α和IL-6的表达,抑制细胞凋亡. miR-181a-5p靶向负调控PIAS1;抑制PIAS1表达逆转了抑制miR-181a-5p对雨蛙肽处理AR42J和MPC-83细胞的凋亡抑制作用.结论抑制miR-181a-5p表达可以抑制雨蛙肽诱导的AP腺泡细胞损伤,其机制可能与靶向调控PIAS1有关.可为AP诊断和治疗提供新靶点和新思路.     

酪酪肽对实验性急性胰腺炎的治疗作用

目的探讨酪酪肽(Peptide YY,PYY)对实验性急性胰腺炎大鼠(AP)的治疗效果,并对其机制进行探讨。方法取40只SD大鼠,雌雄不限,随机分为胰腺炎组(n=20)和酪酪肽治疗组(n=20),急性胰腺炎模型采用经腹腔注射精氨酸完成,测定48 h后大鼠血清及胰腺组织匀浆中的丙二醛(MDA)含量,血清中肿瘤坏死因子-α含量,光镜下观察胰腺组织的病理变化。结果 PYY能有效减轻AP大鼠胰腺的病理损伤,与胰腺炎组相比,PYY组血清中及胰腺组织匀浆中的MDA含量下降,血清中肿瘤坏死因子-α的含量下降。结论 PYY可能通过抗氧自由基的生成,减轻组织的过氧化损伤,以及通过抑制某些细胞因子的作用而对急性胰腺炎发挥保护作用。     

程序性坏死在急性胰腺炎中的研究进展

腺泡细胞的死亡是重症急性胰腺炎发病过程中的核心环节,腺泡细胞的死亡方式主要包括凋亡和坏死两种。迄今为止,关于细胞凋亡的信号通路已被研究得较为透彻。相对而言,对另一种细胞死亡机制坏死的研究却知之甚少。新近发现的RIP激酶家族RIP1、RIP3参与并调控了程序性坏死,RIP1-RIP3复合体的形成及其互相磷酸化可作为程序性坏死的特异性指标,因此,对程序性坏死相关蛋白的进一步鉴定及确切分子机制的研究,将对急性胰腺炎发病机制的阐明及新的治疗靶点的提出产生深远影响。     

RIP3介导的程序性坏死通路在LPS诱导的小鼠急性肺损伤模型中的作用

目的研究受体相互作用蛋白(RIP3)介导的程序性坏死通路在脂多糖(LPS)诱导的小鼠急性肺损伤模型(ALI)中的作用。方法将野生小鼠和RIP3敲除小鼠各30只分为四组:(a)Control RIP3-KO,(b)LPS RIP3-KO,(c)Control RIP3-WT,(d)LPS RIP3-WT。每组各15只,脂多糖组(LPS组)经小鼠气管套管滴入30mg/kg LPS,对照组经气管套管滴入等体积磷酸盐缓冲液(PBS),然后观察比较四组小鼠肺部病理损伤,小鼠直肠温度和生存率,并检测小鼠肺组织冰冻切片中坏死细胞计数和肺泡灌洗液中高迁移率族蛋白B1(HMGB1)水平。结果 RIP3敲除后,小鼠肺部病理损伤减轻,低体温症状得到明显改善,且死亡率降低。冰冻切片显示的肺组织坏死细胞计数减少,且支气管肺泡灌洗液中HMGB1表达水平也降低。结论 RIP3敲除能一定程度保护小鼠免受LPS诱导的急性肺损伤,并能减少肺组织细胞坏死的发生。     

JAM—C单抗对小鼠急性坏死性胰腺炎急性肺损伤的保护作用

急性肺损伤是重症急性胰腺炎（SAP）的主要并发症,是造成SAP高病死率的一个重要原因。目前研究认为,SAP导致的炎症细胞过度激活和肺部浸润是急性肺损伤甚至急性肺功能衰减的中心环节[1]。连接黏附分子C（junctional adhesion molecule—C,JAM．C）是近年新发现的在血管内皮细胞上分布的细胞黏附分子。     

基于SIRT1/FOXO1通路探讨茶多酚对急性胰腺炎肺损伤大鼠的保护作用

目的:基于SIRT1/FOXO1通路探讨茶多酚(TP)对急性胰腺炎(AP)肺损伤大鼠的保护作用。方法:选取60只SD大鼠,随机分为假手术组、模型组、TP(100 mg/kg)组、SIRT1抑制剂尼克酰胺(NA组,100 mg/kg)组、TP+尼克酰胺组(TP+NA组,TP、NA均为100 mg/kg),每组12只。采用逆行胆胰管注射5%牛磺胆酸钠(1 m L/kg)建立AP肺损伤大鼠模型,给药5 d后处死大鼠,测量腹水量,肺组织干、湿质量,计算干湿重比值(W/D)。苏木精-伊红染色(HE)观察各组大鼠肺组织病理情况,进行Holfbauer评分。采用全自动血气分析仪检测血氧分压(Pa O2)、二氧化碳分压(Pa CO2)、氧合指数(OI)等指标。用酶联免疫吸附法(ELISA)试剂盒检测大鼠血清肿瘤坏死因子α(TNF-α)、白介素6(IL-6)及淀粉酶水平,蛋白免疫印迹法检测SIRT1、FOXO1及acely-FOXO1蛋白表达。结果:与假手术组比较,模型组大鼠腹水量、肺组织W/D、Holfbauer评分、血Pa CO2、TNF-α、IL-6、淀粉酶水平及acely-FOXO1蛋白表达显著升高,Pa O2、OI及SIRT1蛋白表达显著降低(均P 0. 05)。与模型组比较,TP组大鼠腹水量、肺组织W/D、Holfbauer评分、血Pa CO2、TNF-α、IL-6、淀粉酶水平及acely-FOXO1蛋白表达降低,Pa O2、OI及SIRT1蛋白表达升高(均P 0. 05),而NA组大鼠腹水量、肺组织W/D、Holfbauer评分、血Pa CO2、TNF-α、IL-6、淀粉酶水平及acely-FOXO1蛋白表达升高,Pa O2、OI、SIRT1蛋白表达降低(均P 0. 05)。与TP+NA组比较,NA组大鼠腹水量、肺组织W/D、Holfbauer评分、血Pa CO2、TNF-α、IL-6、淀粉酶水平及acely-FOXO1蛋白表达升高,Pa O2、OI、SIRT1蛋白表达降低(均P 0. 05),而TP组大鼠腹水量、肺组织W/D、Holfbauer评分、血Pa CO2、TNF-α、IL-6、淀粉酶水平及acely-FOXO1蛋白表达降低,Pa O2、OI、SIRT1蛋白表达升高(均P 0. 05)。各组大鼠FOXO1蛋白表达差异无统计学意义(P0. 05)。结论:TP可能通过上调SIRT1/FOXO1信号,改善AP肺损伤大鼠的肺组织损伤。     

Role of endogenous platelet-activating factor in caerulein-induced acute pancreatitis in rats: Protective effects of a PAF-antagonist

The role of endogenous platelet-activating factor (PAF) in the pathogenesis of acute pancreatitis was investigated by determining whether CV-6209, a selective PAF antagonist, confers protection against caerulein-induced acute pancreatitis in rats. Continuous intravenous infusion of caerulein (5 micrograms/kg x h) induced time-dependent increase in serum pancreatic enzymes, pancreatic weight, and protein content of the pancreas, and produced histologic evidence of acute pancreatitis. Pretreatment with CV-6209 (1 mg/kg) significantly inhibited the elevation of serum pancreatic enzymes, pancreatic weight, and protein content of the pancreas. Caerulein-induced tissue oedema and recruitment of leucocytic cells were markedly ameliorated with CV-6209. Platelet-activating factor may be released endogenously and may play a role during acute pancreatitis.     

Exocrine function of caerulein-induced acute pancreatitis in anesthetized rats

Exocrine function was studied in anesthetized rats that had received two specific doses of caerulein (maximal stimulation and supramaximal stimulation). Male Wistar rats (body weight, 200–250 g) were divided into three groups: the control group (4-h saline infusion), the maximal stimulation group (0.25 g/kg per h caerulein for 4 h), and the caerulein pancreatitis group (10g/kg per h for 4 h). Histologically, inter-stitial edema and cytoplasmic vacuolization were observed only in the caerulein pancreatitis group, with no abnormal findings in the other groups. The volume of pancreatic juice was significantly increased in both the maximal stimulation group and the caerulein pancreatitis group. The protein ouput and the amylase output in the 1st h of caerulein infusion were also significantly increased, to 459% and 338% in the maximal stimulation group, and to 925% and 1430% respectively, in the caerulein pancreatitis compared to the baseline values. We also found that the pancreatic juice of the caerulein pancreatitis group contained precipitated protein, and high trypsin activity, and protein degradation was confirmed by electrophoresis. These findings were not observed in the other groups. These results strongly suggest that hypersecretion and the appearance of trypsin activity in pancreatic juice plays an important role in the induction of histological changes in this pancreatitis model in anesthetized rats.     

Effect of endothelin-1 receptor antagonists on histological and ultrastructural changes in the pancreas and trypsinogen activation in the early course of caerulein-induced acute pancreatitis in rats

AIM: To assess the effect of non-selective ETA/B (LU 302872) and selective ETA (LU 302146) antagonist on pancreatic histology and ultrastructure of acinar cells in connection with trypsinogen activation in early caerulein-induced AP. METHODS: Male Wistar rats with caerulein-induced AP, lasting 4 h, were treated i.p. with 10 and 20 mg/kg b.w. of each antagonist. Edema, inflammatory infiltration, necrosis and vacuolization of acinar cells in the pancreas were scored at 0-3 scale. Free active trypsin (FAT), total potential trypsin (TPT) after activation with enterokinase, and index of trypsinogen activation (%FAT/TPT) were assayed in pancreatic homogenates. RESULTS: In untreated AP, the edema, inflammatory infiltration, necrosis and vacuolization increased as compared to control healthy rats (P<0.01). None of the treatment exerted any meaningful effect on the edema and inflammatory infiltration. The selective antagonist increased slightly the necrosis score to 0.82±0.06 at higher dose (P<0.05) vs 0.58±0.06 in untreated AP. The non selective antagonist increased slightly the vacuolization score to 2.41±0.07 at higher dose (P<0.01) vs 1.88±0.08 in untreated AP. The decrease in the number of zymogen granules, disorganization of endoplasmic reticulum, autophagosomes and cytoplasmic vacuoles were more prominent in treated AP than in untreated AP groups. %FAT/TPT in untreated AP increased about four times (18.4±3.8 vs 4.8±1.3 in control group without AP, P<0.001). Treatment of AP with both antagonists did not affect significantly augmented trypsinogen activation. CONCLUSION: The treatment with endothelin-1 receptors (non-selective ETA/Band selective ETA) antagonists has essential effect neither on the edema and inflammatory infiltration nor on trypsinogen activation observed in the early course of caerulein-induced AP. Nevertheless a slight increase of the necrosis and vacuolization score and some of the ultrastructural data could suggest the possibility of their undesired effects in caerulein-induced AP at investigated doses.     

硫氧还蛋白-1在急性坏死性胰腺炎并急性胃黏膜损伤中的作用

目的探讨硫氧还蛋白-1（TRX-1）在实验性急性坏死性胰腺炎（ANP）并急性胃黏膜损伤发病机制中的作用以及抗氧化剂褪黑素对其的影响。方法72只大鼠随机分为对照组（C组,n=24）、ANP组（A组,n=24）和褪黑素干预组（M组,n=24）。A组分3次腹腔内注射6％L-精氨酸（L—Arg）1．5g／kg建立ANP模型;C组同法注射等量生理盐水;M组于首次注射L—Arg前0．5h腹腔内注射1％褪黑素50μg／kg。各实验组大鼠于末次腹腔内注射后6h、12h和24h分批处死。光镜下观察胰腺和胃组织并进行病理学评分,采用免疫组化检测TRX-1在胃黏膜的表达,并检测胃黏膜中MDA、MPO的含量。结果A组各时点胃黏膜TRX-1的染色积分及MDA、MPO的含量明显高于C组（P均〈0．05）;M组各时点胃黏膜中TRX一1的染色积分及MDA、MPO的含量明显低于A组（P均〈0．05）,胰腺和胃组织病理改变较A组明显减轻（P均〈0．05）。结论内源性的TRX-1可能是胃黏膜组织抵御氧化应激损伤的重要因子之一,TRX-1的表达量可能与组织氧化应激损伤的严重程度有关。外源性的褪黑素在ANP时可能通过其抗氧化作用,减轻胃黏膜氧化应激损伤的程度,对胃黏膜有一定的保护作用。     

Protective effects of endothelin-1 on acute pancreatitis in rats

Endothelin-1, a 21-residue peptide isolated from vascular endothelial cells, has a broad spectrum of actions. To clarify the involvement of endothelin-1 in acute pancreatitis, we examined the effects of endothelin-1 and its receptor antagonist BQ-123 on cerulein-induced pancreatitis in rats. Rats were infused intravenously with heparin-saline (control), endothelin-1 (100 pmol/kg/hr), cerulein (5 µg/kg/hr), or cerulein plus endothelin-1 for 3.5 hr. In another experiment, cerulein or cerulein plus BQ-123 (3 mg/kg/hr) was infused. Infusion of cerulein caused hyperamylasemia and pancreatic edema. Endothelin-1, when infused with cerulein, decreased the extent of pancreatic edema with a significant increase in the pancreatic dry- to wet-weight ratio. Histological changes induced by cerulein were markedly attenuated when endothelin-1 was given with cerulein. In contrast, endothelin-receptor blockade with BQ-123 further augmented pancreatic edema caused by cerulein. The extent of inflammatory cell infiltration was greater when BQ-123 was given with cerulein. Endothelin-1 or BQ-123 had no influence on hyperamylasemia. This study suggests that endothelin-1 has protective effects on experimental acute pancreatitis.Supported by a grant from the Ministry of Education, Japan (No. B-04454330).     

高脂血症性急性胰腺炎与胆源性胰腺炎的临床对比分析

目的对比分析高脂血症性急性胰腺炎（hyperlipidemic acute pancreatitis,HLAP）与急性胆源性胰腺炎（acute biliary pancreatitis,ABP）的临床特点。方法回顾性对比分析我院2005年8月～2010年8月间收治的28例HLAP和64例ABP患者的临床资料。结果 HLAP组BMI、重症患者比例、Ranson评分≥3、CT分级为D、E及APACHEII≥8分者均较ABP组高（P〈0.05）。HLAP组血清TG、GLU、UA均显著高于ABP组,而ALT、AKP、TBIL、DBIL及血AMY均显著低于ABP组（P〈0.05）。两组患者平均住院时间无统计学差异（P〉0.05）。HLAP组患者死亡率为14.3%）,显著高于ABP组的1.5%（P〈0.05）。结论与ABP组相比,HLAP组通常病情较重,多为SAP且常不伴有血淀粉酶的显著升高,且死亡率高。