慢性胰腺炎胰腺纤维化发病机制研究新进展

慢性胰腺炎(chronic pancreatitis, CP)是由多种因素引起的胰腺内外分泌功能紊乱,可导致胰腺结构和功能发生不可逆性损伤,是临床常见的消化系统疾病。CP的病理特点是腺泡细胞损伤导致巨噬细胞等多种炎症细胞浸润,从而分泌大量促炎细胞因子,在胰腺组织微环境中引起胰腺星状细胞活化,进而产生大量的细胞外基质,表现为胰腺纤维化。而新近的研究提示:胰腺纤维化是一种动态病理现象,需要由多种自分泌和旁分泌的细胞因子组成复杂的网络,作用于相应的信号通路,最终导致纤维化形成。现以CP胰腺组织微环境中出现的主要细胞,如胰腺星状细胞、巨噬细胞、腺泡细胞及其在CP胰腺纤维化进展中的变化和作用为切入点,对CP胰腺纤维化的发病机制研究进展做一综述。     

胰腺星状细胞活化相关的信号转导通路

胰腺纤维化是慢性胰腺炎（chronic pancreatitis,CP）和胰腺癌主要的病理学特征,活化的胰腺星状细胞（pancreatic stellate cells,PSCs）是公认的致胰腺纤维化的主要效应细胞。PSCs的活化涉及到几个重要的信号转导通路：有丝分裂原活化蛋白激酶（mitogen-activated protein kinases,MAPK）、磷酯酰肌醇3激酶（phosphatidylinositol 3-kinase,PI3K）=、Smad信号转导蛋白、过氧化物酶体增生物激活受体-γ（PPAR-γ）、Rho-ROCK等细胞内信号途径。探讨这些信号通路在胰腺纤维化中所起的作用对慢性胰腺炎、胰腺癌及糖尿病的治疗有重要意义。现就与PSCs激活有关的信号通路的研究结合最新进展作一综述。     

大柴胡汤调控TGF-β/Smad信号通路对DBTC联合乙醇诱发小鼠胰腺纤维化的防治作用

目的:探讨大柴胡汤对二丁基二氯化锡(DBTC)联合乙醇所致小鼠慢性胰腺炎胰腺纤维化中TGF-β/Smad信号通路的影响及大柴胡汤防治胰腺纤维化的作用机制。方法:昆明小鼠96只,随机分成空白组(Con组)、慢性胰腺炎组(CP组)、大柴胡汤治疗组(DCHD组)(n=32)。一次性尾静脉注射DBTC(8 mg/kg)联合10%乙醇饲喂代替正常饮水复制小鼠CP模型。注射DBTC 3 d后小鼠又随机分为CP组和DCHD组,DCHD组予大柴胡汤(1 g/ml,6 g/kg·d)灌胃,并伴随10%乙醇饲喂代替正常饮水。各组在1、2、4、8周分批处死小鼠(n=8),观察胰腺组织的形态学变化及血清淀粉酶、透明质酸的变化;检测胰腺组织MMP-1/TIMP-1 mRNA的表达以及胰腺组织Ⅰ型胶原、TGF-βRⅠ、p-Smad 2/3、Smad 7蛋白的表达。结果:与空白组相比,CP组2周、4周血清淀粉酶及透明质酸处于较高水平,8周时淀粉酶明显降低,而透明质酸水平进一步升高(P0.05);DCHD组血清淀粉酶及透明质酸含量明显低于CP组(P0.01)。与空白组相比,CP组胰腺组织COLA1、TGF-βRⅠ、p-Smad 2/3表达持续升高,Smad7蛋白表达明显减少;DCHD治疗组可降低COLA1的表达水平有效抑制CP小鼠胰腺TGF-βRⅠ、p-Smad 2/3表达,使Smad7蛋白表达升高。与空白组相比,CP 2周、4周胰腺MMP-1 mRNA表达持续降低,TIMP-1 mRNA表达随造模时间延长明显升高(P0.01);DCHD组各时间点胰腺MMP-1表达明显增多,TIMP-1表达减少(P0.05)。结论:大柴胡汤通过抑制TGF-β/Smad信号通路活化,调节MMP-1/TIMP-1的平衡,发挥防治慢性胰腺炎胰腺纤维化的作用。     

抗胰腺星状细胞药物研究进展

慢性胰腺炎传统治疗方法效果不确定,需要寻找新型有效药物。活化的胰腺星状细胞在胰腺纤维化过程中起了重要的作用,使之成为新的治疗靶点。活化PSC的物质分为三类,即炎症介质、氧化应激和毒素。本文就近年来针对以上不同活化PSC的介质和相关通路的抗星状细胞药物进行综述。     

胃癌患者血清IL-17、IL-6和TGF-β1水平及其临床意义

目的:探讨胃癌患者外周血中白介素17(IL-17)、白介素6(IL-6)和转化生长因子-β1(TGF-β1)的表达水平及其临床意义。方法:选择2009年1月~2010年1月我院收治的50例胃癌患者(观察组)及同期50例健康对照者(对照组)为研究对象,采用ELISA法检测和比较其外周血中IL-17、IL-6和TGF-β1的水平,并分析胃癌患者外周血中IL-17、IL-6和TGF-β1水平与其临床病理特征之间的相关性。结果:观察组患者外周血中IL-17、IL-6和TGF-β1的水平分别为(8.51±2.68)pg/ml、(7.81±5.41)pg/ml和(1093.42±831.21)pg/ml,均明显高于健康对照组(P0.01)。胃癌患者的血清IL-17、TGF-β1的水平与其年龄、性别、临床分期、有无淋巴结转移、分化程度、肿瘤部位及大小均无明显相关性(P0.05);而血清IL-6的水平与肿瘤的大小相关(P0.05),但与其他临床病理特征无关(P0.05);血清IL-17水平与IL-6、TGF-β1的水平均无明显相关性(P0.05)。结论:血清IL-17、IL-6和TGF-β1水平的升高与胃癌的发生有关,但IL-6和TGF-β1可能不是血清中IL-17生成的诱导因子。     

白细胞介素-6在急性胰腺炎中的作用及其机制研究

目的:明确白细胞介素-6(IL-6)在小鼠急性胰腺炎中的作用及其机制研究。方法:通过胰胆管结扎的方法诱导小鼠急性胰腺炎;分离小鼠胰腺腺泡细胞。采用ELISA方法检测胰腺组织或腺泡细胞裂解物中的细胞因子;通过western blot分析检测组织或细胞中IL-6或ERK表达。结果:IL-6浓度在胰腺组织和腺泡细胞中显著增加(P0.05)。在离体原代小鼠腺泡细胞,TNF-α刺激增加IL-6释放(P0.05);与此同时,IL-6刺激可增加其它促炎性细胞因子的释放,两者都涉及ERK MAP激酶通路。黄酮类化合物木犀草素抑制IL-6刺激引起白细胞介素-6(IL-6)和人巨嗜细胞激活蛋白-1(CCL2/MCP-1)释放。最后进一步证实,IL-6激活人胰腺组织中的ERK。结论:IL-6在急性胰腺炎中增加,激活炎症通路并加重急性胰腺炎。     

胰腺星状细胞的调控及转归

活化的胰腺星状细胞(pancreatic stellate cells,PSCs)是胰腺炎致胰腺纤维化的主要效应细胞。近年来,学者普遍认为,胰腺纤维化早期阶段是动态可逆的,因此,若在胰腺损伤的早期阶段,抑制PSCs的增殖、迁移,减少损伤部位PSCs的数目,降低细胞外基质(extracellular matrix,ECM)的生成,将可能逆转胰腺纤维化。该文以PSCs为靶点阐述了抗胰腺纤维化的新策略。     

胰腺星状细胞在胰腺内外分泌疾病中的作用

胰腺纤维化是胰腺炎、胰腺癌主要的病理学特征。活化的胰腺星状细胞(pancreatic stellate cell,PSC)是胰腺炎致胰腺纤维化的主要效应细胞,在胰腺炎与胰腺癌的纤维化进程中发挥重要作用。近期研究发现,PSC也存在于糖尿病动物胰岛中,可能参与糖尿病胰岛纤维化及β细胞衰竭的发展进程。现就PSC与胰腺炎、胰腺癌及糖尿病关系的研究进展作一综述。     

HSC的活化、增殖与TGF-β1及其Ⅰ型受体在中晚期纤维化肝组织中的改变及护杆片对其的影响

目的 探讨护肝片对中、晚期纤维化大鼠肝组织肝星状细胞(HSC)的活化与增殖及转化生长因子-β1(TGF-β1)及其Ⅰ型受体(TβRⅠ)表达的影响.方法 采用12.5% CCl4诱导的大鼠肝纤维化模型,自造模之日起,大鼠分组灌胃给药(护肝片921mg·kg-1)或溶媒,每日一次,直至8或13周末,分别处死动物,取左叶肝组织石蜡包埋,制作组织芯片,免疫组化S-P法检测大鼠肝组织α-平滑肌肌动蛋白(α-SMA)、TGF-β1及TβRⅠ蛋白的表达,并用MetaMorph图像分析系统计数α-SMA阳性细胞数、对TGF-β1及TβRⅠ蛋白表达量进行定量分析.结果 1.模型复制8周和13周,模型组的肝损伤及其纤维化分级均明显高于正常组(P＜0.01),护肝片组的肝损伤及其纤维化分级均轻于模型组.2.模型复制8周和13周,模型组活化的HSC(即α-SMA阳性细胞)数量较正常组明显增多、TGF-β1及TβRⅠ蛋白的表达较正常组明显增强(P＜0.01);3.护肝片显著抑制8、13周纤维化肝组织HSC的活化与增殖和TGF-β1及TβRⅠ蛋白的表达(P＜0.01).结论 抑制HSC的活化与增殖和TGF-β1及TβRⅠ的表达可能是护肝片抗肝纤维化作用的靶点之一.     

胰腺微环境外泌体miRNA参与胰腺炎症和纤维化的发病机制研究进展

慢性胰腺炎(chronic pancreatitis, CP)发病率逐年上升，目前尚无明确根治性治疗方法且后期有进展为胰腺癌的风险。CP的典型病理学特征是胰腺慢性炎症和纤维化，CP进展与胰腺微环境中三种主要细胞(腺泡细胞、巨噬细胞以及胰腺星状细胞)间的相互作用密切相关，然而它们具体是如何进行细胞间联系的目前尚不清楚。新近研究表明外泌体作为细胞间重要的通讯介质，其携带的miRNA可通过调控主要细胞内基因表达和信号通路等影响CP的发生发展。本文围绕胰腺微环境中外泌体来源miRNA与三种主要细胞相互作用的机制，对其最新研究进展进行归纳和总结分析，以期为CP发病机制的深入认识提供参考。     

Effect of pancreatic polypeptide-antiserum on bombesin-stimulated pancreatic exocrine secretion in dogs

Bombesin is a potent stimulus of both pancreatic protein secretion and plasma pancreatic polypeptide (PP) release in dogs. Physiological plasma levels of PP have been shown to inhibit pancreatic exocrine secretion in dogs. We examined the question whether the concomitant release of PP exerts a suppressive action on the pancreatic exocrine response to bombesin in dogs by measuring pancreatic exocrine secretion with and without in vivo immunoneutralization of PP with a high affinity PP-antiserum. Bombesin was infused in a dose of 150 ng/kg·hr, resulting in a rise of plasma PP from 24±5 to 224±25 pM (p<0.01). Before this bombesin infusion, 7 ml of normal rabbit serum had been administered to the dogs (n=8). At a later stage, the study was repeated after administration of 7 ml of PP-antiserum to the same animals. The bombesin induced increase in pancreatic exocrine secretion during administration of PP-antiserum (flow rate 24±10 ml/hr, protein output 1.35±0.43 g/hr, and bicarbonate output 3.25±1.42 mmol/hr) was not significantly different from that during control rabbit serum (flow rate 21±7 ml/hr, protein output 1.26±0.38 g/hr, and bicarbonate output 3.18±1.10 mmol/hr). It is therefore concluded that the pancreatic exocrine response to bombesin is not affected by the concomitant secretion of PP.     

24-Hour plasma secretin level and pancreatic secretion in dog

Plasma secretin concentrations were determined and duodenal pH was recorded continuously for a period of 24 hours after ingestion of a meal in 3 dogs with gastric cannula and duodenal cannula and in 4 dogs with pancreatic fistulae. The mean plasma secretin concentration increased significantly after a meal and it remained elevated for the first 12-hour period (peak at 30 min). Duodenal pH frequently decreased below 4.5 during the first 12-hour postprandial period, but it remained above 5.0 during the second 12 hours. Pancreatic secretion peaked during the first hour of meal ingestion and remained elevated until the end of 12 hours. The increased plasma secretin level in pancreatic fistula dog during the postprandial period was significantly greater than that of duodenal cannula dog, but the trends of increase in the secretin levels were quite identical. The present study indicates that: (1) plasma secretin concentration increases significantly within 30 min after a meal and remains increased during the first 12-hour period, (2) duodenal pH frequently decreased below 4.5 during the same 12 hours but more frequently during the first 6 hours, and (3) a significant increase in pancreatic water, HCO₃^? and protein occurred during the same time period.     

干细胞在胰腺癌中的研究进展

胰腺癌是预后程度极差的恶性肿瘤,已初步证实胰腺干细胞可转化为胰腺癌细胞。成功分离和鉴定了胰腺癌干细胞并对其与转移、耐药的关系和信号通路异常的关系进行了初步研究。深入理解干细胞在胰腺癌中的作用,可能根本改变临床胰腺癌防治的方式。     

改良单层胰肠吻合术在胰十二指肠切除术带蒂大网膜包埋中的应用

目的:探讨带蒂大网膜包埋的改良单层胰肠吻合法重建消化道的胰十二指肠术的临床疗效。方法:回顾性分析2012年9月-2014年12月在我院行胰十二指肠切除术带蒂大网膜包埋改良单层胰肠吻合术的34例患者的临床资料。统计患者的手术时间、胰肠吻合时间、术后出血量、住院时间以及并发症的发生情况。结果:(1)手术平均时间(2.9±1.4)h,胰肠吻合平均时间(14±2.1)min,术后平均出血量(380±60)m L。所有患者经治疗后均治愈出院,住院时间平均(13.0±2.4)天。(2)术后并发症发生率为8例(23.5%),其中胰瘘2例(5.8%),为A级胰瘘;腹部感染3例(8.8%);腹腔出血2例(5.8%);胃排空延迟1例(2.9%)。无手术死亡者,无因严重并发症需要再次手术者。术后病理学诊断胰头癌18例,胆总管下癌8例,壶腹部癌5例,十二指肠乳头癌3例。结论:带蒂大网膜包埋的改良单层胰肠吻合能够减少术后胰瘘、出血、感染等并发症,提高手术成功率,值得临床进一步推广。     

Hexose metabolism in pancreatic islets: Succinate dehydrogenase activity in islet homogenates

Succinate dehydrogenase activity was measured in rat pancreatic islet homogenates incubated in the presence of [1,4-¹⁴C]succinate, the reaction velocity being judged through the generation of ¹⁴CO₂ in the auxiliary reactions catalysed by pig heart fumarase and chicken liver NADP-malate dehydrogenase. In the presence of 1·0 mM succinate, the reaction velocity averaged 5·53 ± 0·44 pmol min^?1 μg^?1 islet protein. The K_m for succinate was close to 0·4 mM and the enzymic activity was restricted to mitochondria. These kinetic results indicate that, under the present experimental conditions, the activity of succinate dehydrogenase does not vastly exceed that of either NAD-isocitrate dehydrogenase or the 2-ketoglutarate dehydrogenase complex, at least when the latter enzymes are activated by ADP and/or Ca²⁺. Nevertheless, the activity of succinate dehydrogenase is sufficient to account for the increase in O₂ uptake evoked in intact islets by the monomethyl ester of succinic acid. It could become a rate-limiting step of the Krebs cycle in models of B-cell dysfunction.     

细胞外基质金属蛋白酶诱导分子(CD147)在胰腺癌细胞及胰腺星状细胞中的表达(英文)

目的:探讨细胞外基质金属蛋白酶诱导分子(CD147)在胰腺癌细胞(Panc-1)及胰腺星状细胞(PSCs)的表达。方法:应用QRT-PCR,免疫细胞化学和免疫印迹分析方法检测Panc-1和PSCs细胞中EMMRPIN的表达,应用脱糖基化试剂N-glycosidase F及Endoglycosidase H鉴定CD147糖基化形式。结果:CD147在Panc-1和PSCs细胞质膜及细胞质中高表达,通过脱糖基化法首次鉴定出胰腺癌细胞及胰腺星状细胞中CD147不同的糖基化修饰。结论:CD147的糖基化修饰具有细胞特异性,可能与细胞恶性程度相关。     

Effect of proton pump inhibitor on amylase release from isolated pancreatic acini

Proton pump inhibitors (PPIs) could inhibit the secretion of gastric acid. Meanwhile, it could also decrease the secretion of other digestive glands besides gastric parietal cell. As we know, PPIs have been widely used to treat acute pancreatitis, and it is effective in clinical practice. However, research showed the side effect of PPIs on acute pancreatitis. The direct effect of PPI on pancreatic secretion is still unknown. Our experiment investigated the direct effect of PPIs on pancreatic exocrine by isolated pancreatic acini. In our study, isolated pancreatic acini were prepared as previously described by Williams, and cerulein was added to stimulate its secretion. The amylase release in the suspension was determined after the administration of different concentrations of omeprazole and Sandostatin; and its activity was also observed in different time phases. In our in vitro study, all results suggest that omeprazole has no direct repression on amylase release from isolated pancreatic acini.     

Pancreatic Cancer: Current Progress and Future Challenges

Pancreatic ductal adenocarcinoma (PDAC), the most common form of pancreatic cancer, remains one of the highly lethal malignancies. The highly refractory nature of clinically advanced disease and lack of a reliable biomarker for early detection are major obstructions in improving patient outcome. The recent efforts, however, in understanding the pancreatic tumor biology have resulted in the recognition of novel addictions as well as vulnerabilities of tumor cells and are being assessed for their clinical potential. This special issue highlights some of the recent progress, complexity and challenges towards improving disease outcome in patients with this lethal malignancy.     

Localization of pancreatic polypeptide (PP)-like immunoreactivity in the pancreatic islets of some teleost fishes

Summary Immunocytochemical staining has revealed that the pancreatic islets of various teleost fishes contain a pancreatic polypeptide (PP)-like substance which cross-reacts with antibodies to mammalian and avian PP. The PP cells were frequently found at the periphery of the islets, as in mammals, and were of irregular shape.Dr. J.R. Kimmel kindly provided antibody to APP and the APP antigen, while anti-BPP and BPP were the gift of Dr. R.E. Chance.Blocks of pancreas from the pike were supplied by Dr. A. Thorpe, from the swordtail by Dr. C. Klein and from the garpike, catfish and eel by Dr. A. Epple. We are most grateful to all these people.This research was partly supported by a grant to one of us (GJP) from the National Institutes of Health, USA (Grant No. AM 17161) and by a grant from the Medical Research Council of Great Britain.     

L364718, a new CCK antagonist, inhibits biological actions of CCK in conscious dogs

The effects of L364718, a new CCK receptor antagonist, on CCK-8 stimulated pancreatic secretion and PP release were examined in three conscious dogs with pancreatic fistulas. L364718 (20 nmol/kg) caused a potent inhibition of CCK-8 stimulated pancreatic protein, amylase and trypsin secretion but not of volume and bicarbonate secretion. Release of PP by CCK was also significantly suppressed by L364718. The degree of inhibition by L364718 was dependent upon the amount of CCK-8 infused. This study demonstrates that L364718 acts as a potent antagonist of CCK's action on pancreatic enzyme secretion and PP release in dogs and suggests that this agent might be a useful tool for studying the physiological role of CCK in conscious animals.