A randomized,placebo-controlled trial of emricasan in patients with NASH and F1-F3 fibrosis

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犬急性心肌缺血后左室功能变化与心肌细胞凋亡

目的观察犬急性心肌缺血后左心室壁动度、射血功能、细胞凋亡与心肌组织中caspase3活性的变化。方法犬30只随机分为实验组15只及对照组15只,实验组结扎左冠状动脉前降支近端,结扎时间分别为10min、30min、60min,每一时间点5只,对照组游离左冠状动脉前降支近端,不结扎。心肌组织行三苯四氮唑(TTC)染色,梗死区为黄白色,非梗死区为砖红色。超声心动图测定左室前壁增厚率及左心室射血分数,原位末端脱氧核苷酸转移酶介导的生物素脱氧尿嘧啶核苷酸缺口末端标记法(TUNEL)检测梗死区心肌组织凋亡细胞数,行caspase3活性测定。结果TTC染色示左室前壁及部分前间隔染色为黄白色,其余区域为砖红色。实验组冠脉结扎后10min,左室前壁增厚率降低,与对照组比较有显著性差异(P<0.05)。左心室射血分数未发生明显改变,与对照组比较无显著性差异(P>0.05)。冠脉结扎后30min至60min,前壁增厚率降低与左心室射血分数进一步下降,与对照组比较有非常显著性差异(P<0.01)。实验组冠脉结扎后10min,梗死区心肌TUNEL阳性细胞数与对照组比较无显著性差异;冠脉结扎后30min至60min,梗死区心肌TUNEL阳性细胞数明显增加,与对照组比较有非常显著性差异(P<0.01)。实验组冠脉结扎后10min,梗死区心肌caspase3荧光值升高,与对照组比较有显著性差异(P<0.05)。30min至60min梗死区心肌caspase3荧光值明显升高,与对照组比较有非常显著性差异(P<0.01)。结论急性心肌缺血后早期,促凋亡基因caspase3激活,缺血心肌细胞凋亡可能为急性心肌缺血的早期病理改变,并且与心肌室壁动度与左室收缩功能降低有一定关系。     

肝豆汤改良方对Wilson''s病模型TX乳鼠神经元内Cyt C/Caspase信号通路的分子调控机制

目的:探讨肝豆汤改良方调控TX乳鼠神经元内细胞色素C(Cyt C)/半胱氨酸天冬氨酸蛋白酶(Caspase)信号通路的分子靶点并观察其相应的调控机制。方法:本实验乳鼠神经元通过原代方法分离培养所得,分为正常组、模型组、肝豆汤改良方组、丁苯酞组,正常组为正常DL乳鼠神经元,用完全培养基培养,模型组为TX乳鼠神经元,用10%空白兔血清培养,肝豆汤改良方组为TX乳鼠神经元,加入含体积浓度(5%,10%,15%,20%)肝豆汤改良方兔血清的培养基继续培养,丁苯酞组为TX乳鼠神经元,用10%含丁苯酞兔血清培养。采用原子吸收分光光度法检测不同浓度含肝豆汤改良方兔血清作用24 h后,对TX乳鼠神经元内微量元素的影响;流式细胞仪检测经肝豆汤改良方兔血清作用后活性氧(ROS)释放量的变化;蛋白质免疫印迹(Western blot)法检测经含肝豆汤改良方兔血清作用后Cyt C,Caspase-9,Caspase-3蛋白的表达。结果:与模型组比较,含肝豆汤改良方兔血清可显著降低TX乳鼠神经元内铜、铁含量,增加锌含量(P0.01)。流式细胞仪检测发现,含肝豆汤改良方兔血清较模型组可显著降低TX乳鼠神经元内ROS的释放量(P0.01)。Western blot检测结果显示与模型组比较,含肝豆汤改良方兔血清可显著降低TX乳鼠神经元内Cyt C,Caspase-9,Caspase-3蛋白表达(P0.01)。结论:肝豆汤改良方可能是通过促进过量铜排出而抑制神经元内Cyt C,Caspase-9,Caspase-3表达,从而减轻高铜对神经元的损伤作用。肝豆汤改良方可通过减少脑内铜含量,进而调控Cyt C/Caspase信号通路达到减轻高铜诱导的神经元损伤的治疗效果。     

Gestational lead exposure induces developmental abnormalities and up-regulates apoptosis of fetal cerebellar cells in rats

Lead (Pb), a known environmental toxicant, adversely affects almost all organ systems. In this study, we investigated the effects of maternal lead exposure on fetal rat cerebellum. Female Sprague–Dawley rats were given lead nitrate in drinking water (0, 0.5, and 1%) for two weeks before conception, and during pregnancy. Fetuses were collected by caesarian section on gestational day 21 and observed for developmental abnormalities. The fetal cerebellar sections from control and 1% lead group were stained with cresyl violet. Immunohistochemical expressions of p53, Bax, Bcl-2, and caspase 3 were quantified by AnalySIS image analyzer (Life Science, Germany). Lead exposure induced developmental abnormalities of eyes, ear, limbs, neck and ventral abdominal wall; however, these abnormalities were commonly seen in the 1% lead-treated group. In addition, lead also caused fetal mortality and reduced body growth in both dose groups and reduced brain weight in the 1% lead-treated group. The fetal cerebella from the 1% lead-treated group showed unorganized cerebellar cortical layers, and degenerative changes in granule and Purkinje cells such as the formation of clumps of Nissl granules. An increase in Bax and caspase 3, and a decrease in Bcl-2 (p?相似文献   

脂氧素 A4预处理对糖尿病大鼠心肌缺血再灌注时Caspase －3、Bcl －2和 Bax 表达的影响

目的：观察脂氧素 A4预处理对链尿佐菌素诱导的糖尿病大鼠心肌缺血再灌注时 Caspase －3、Bcl －2和 Bax 表达的影响。方法雄性 SD 大鼠60只,随机分为 CS、CI／R、CLX、DS、DI／R、DLX 组共6组（n ＝10）。 CS、CI／R、CLX组采用腹腔注射链尿佐菌素55 mg／kg 制备糖尿病模型。 CI／R、DI／R组建立大鼠心肌缺血再灌注模型,结扎冠脉左前降支30 min,CS 组和 DS 组仅穿线不结扎,CI／R组和 DI／R组缺血前5 min 经股静脉注射2 mL／kg 生理盐水,CLX组和 DLX组缺血前5 min 经股静脉注射脂氧素 A42.5μg／kg。再灌注4 h 时处死大鼠,取心肌组织,采用 HE 染色法光镜下观察缺血心肌组织形态学改变,通过 RT －PCR 和 Western blot 法检测缺血心肌 Caspase －3、Bcl －2和 Bax的表达水平,并计算 Bcl －2与 Bax 表达的比值（Bcl －2／Bax）。结果CLX组和 DLX组心肌组织病理学损伤较 CI／R组和 DI／R组减轻,Caspase －3和 Bax 的表达量减少,Bcl －2的表达量增加,Bcl －2／Bax 比值升高（P ＜0.05）。结论脂氧素 A4预处理能够下调糖尿病大鼠心肌缺血再灌注时 Caspase －3和 Bax 的表达,上调 Bcl －2的表达,使 Bcl －2／Bax 比值升高。     

Resveratrol pretreatment protects rat hearts from ischemia/reperfusion injury partly via a NALP3 inflammasome pathway

Inflammatory responses are key players in myocardial ischemia/reperfusion (I/R) injury. Our previous studies showed that resveratrol alleviated I/R injury in myocardial I/R animal models, but whether the NALP3 inflammasome pathway contributes to the mechanisms remains to be elucidated. In this study, we explored the modulation effect of resveratrol on myocardial I/R-induced inflammatory responses in rats. Myocardial I/R rat animal models were induced by occlusion of the left anterior descending coronary arteries (LADs) for 30 min, followed by 2 h of reperfusion. Resveratrol was administered in different doses (2.5, 5, and 10 mg/kg) at the same time as the onset of reperfusion. The serum concentrations of the trinitrotoluene (TnT) and MB isoenzyme creatine kinase (CK-MB) were detected using an automatic biochemical analyzer. Myocardial ultrastructure and morphology were observed with an electron microscope and a light microscope. Myocardial ischemia and infarct sizes were evaluated using Evans blue and tetrazolium chloride (TTC) staining. The NALP3, Caspase1, interleukin 1β (IL-1β) and interleukin 18 (IL-18) mRNA levels were evaluated using RT-PCR. The NALP3 and Caspase1 protein expression levels were detected by western blotting. The IL-1β and IL-18 content in peripheral blood was measured by enzyme-linked immunosorbent assay (ELISA). The myocardial structure in myocardial ischemia reperfusion injury (MI/RI) rats was extensively damaged. After preconditioning with different concentrations of resveratrol (2.5, 5 and 10 mg/kg), the pathology and morphology were significantly improved in a dose-dependent manner. Our results showed that resveratrol treatment significantly reduced the infarct volume and myocardial fibrosis, resulting in myocardial cells that lined up in a more orderly fashion and dose-dependent decreases in TnT and CK-MB levels in the serum of the I/R rats. Resveratrol also significantly modulated mRNA and protein levels by down-regulating NALP3 and Caspase1 expression and IL-1β and IL-18 activation. These results suggest that the NALP3 inflammasome is activated during the myocardial I/R injury process and that the secretion of the inflammatory cytokines IL-1β and IL-18 mediates the cascade inflammatory response. Resveratrol may play an important role in protecting the myocardium against I/R injury in rats by inhibiting the expression and activation of the NALP3 inflammatory body. Therefore, the attenuation of the inflammatory response may be involved in the cardioprotective mechanisms of resveratrol in response to myocardial I/R injury.     

Potassium efflux fires the canon: Potassium efflux as a common trigger for canonical and noncanonical NLRP3 pathways

Murine caspase‐11 and its human orthologues, caspase‐4 and caspase‐5, activate an inflammatory response following cytoplasmic recognition of cell wall constituents from Gram‐negative bacteria, such as LPS. This inflammatory response involves pyroptotic cell death and the concomitant release of IL‐1α, as well as the production of IL‐1β and IL‐18 through the noncanonical NLR family, pyrin domain containing 3 (NLRP3) pathway. This commentary discusses three papers in this issue of the European Journal of Immunology that advance our understanding of the roles of caspase‐11, ‐4, and ‐5 in the noncanonical pathway. By utilizing the new gene editing technique, clustered regularly interspaced short palindromic repeats (CRISPR), as well as sensitive cell imaging techniques, these papers establish that cytoplasmic LPS‐dependent IL‐1β production requires the NLRP3 inflammasome and that its activation is dependent on K⁺ efflux, whereas IL‐1α release and pyroptotic cell death pathways are NLRP3‐independent. These findings expand on previous research implicating K⁺ efflux as the principal trigger for NLRP3 activation and suggest that canonical and noncanonical NLRP3 pathways are not as dissimilar as first thought.     

Mitochondria in Neutrophil Apoptosis

Central in the regulation of the short life span of neutrophils are their mitochondria. These organelles hardly contribute to the energy status of neutrophils but play a vital role in the apoptotic process. Not only do the mitochondria contain cytotoxic proteins that are released during apoptosis and contribute to caspase activation, but they also act as sensors of the metabolic and redox state of the cell and as scavengers of free Ca2+. The balance of the expression and activity of the proapoptotic and antiapoptotic members of the Bcl-2 family of proteins determines the life span of neutrophils, because these proteins are essential for the formation of a permeability transition pore in the mitochondria and also seem to control the release of Ca2+ from the endoplasmic reticulum and thereby mitochondrial energy metabolism.