外感清热解毒方对脂多糖诱导大鼠急性肺损伤的影响

目的：探讨外感清热解毒方对脂多糖（LPS）诱导急性肺损伤（ALI）大鼠的影响及作用机制。方法：20只雄性Wistar大鼠随机分为对照组、模型组、外感清热解毒方组、miR-495抑制剂组。气管滴注LSP（5 mg/kg）成功复制ALI大鼠模型,给予相应干预。定量PCR检测大鼠肺组织miR-495水平;苏木精-伊红（HE）染色观察肺组织病理改变;酶联免疫吸附试验检测肺泡灌洗液（BALF）中白细胞介素-6（IL-6）、肿瘤坏死因子-α（TNF-α）、IL-1β、IL-18、IL-10炎症介质和髓过氧化物酶（MPO）活性;蛋白质免疫印迹法检测肺组织核苷酸结合寡聚化结构域样受体蛋白3（NLRP3）、凋亡相关微粒蛋白（ASC）、胱天蛋白酶-1（Caspase-1）、GSDMD蛋白表达。结果：与对照组比较,模型组大鼠肺组织miR-495表达下调（P<0.05）,出现病理损伤,BALF中IL-6、TNF-α、IL-1β、IL-18含量升高,IL-10含量下降,MPO活性增强;肺组织NLRP3、ASC、Caspase-1蛋白表达增加（均P<0.05）。与模型组和miR-495抑制剂组比较,外感清热解毒方组大鼠肺组织miR-495表达上调（P<0.05）,病理损伤减轻,BALF中IL-6、TNF-α、IL-1β、IL-18含量下降,IL-10含量升高,MPO活性减弱;NLRP3、ASC表达下调（均P<0.05）,Caspase-1表达差异无统计学意义（P>0.05）。除对照组外,均可见GSDMD蛋白切割,外感清热解毒方组蛋白切割表达水平明显低于模型组和miR-495抑制剂组。结论：外感清热解毒方对ALI大鼠具有保护作用,其机制可能与调控miR-495/NLRP3/GSDMD信号通路,减轻炎症反应,抑制细胞焦亡有关。     

HMGB1/Caspase-1/GSDMD信号轴介导肝细胞焦亡在肝脏缺血-再灌注损伤中的作用

目的  探讨高迁移率族蛋白1（HMGB1）/半胱氨酸天冬氨酸蛋白酶（Caspase）-1/Gasdermin D（GSDMD）信号轴介导肝细胞焦亡在肝脏缺血-再灌注损伤（IRI）中的作用。方法  将C57BL/6小鼠随机分为假手术组（Sham组）、IRI 2 h组、IRI 6 h组、IRI 12 h组、甘草酸（GA）+Sham组和GA+IRI 12 h组（每组8只）;将AML12细胞大致均匀地分为Sham组、IRI 12 h组、GA+Sham组和GA+IRI 12 h组。采用酶联免疫吸附试验（ELISA）检测各组小鼠血清丙氨酸转氨酶（ALT）、天冬氨酸转氨酶（AST）、白细胞介素（IL）-1β和IL-6的水平;采用逆转录聚合酶链反应（RT-PCR）检测肝组织中IL-1β和IL-6信使核糖核酸（mRNA）水平;比较各组小鼠肝脏缺血病理学评分和细胞凋亡情况;采用免疫组织化学（免疫组化）法检测各组小鼠肝组织中HMGB1的表达情况;采用蛋白质印迹法检测小鼠肝组织和AML12细胞中HMGB1、Caspase-1、GSDMD蛋白的表达水平。结果  与Sham组比较,IRI后各组小鼠血清中ALT、AST、IL-1β、IL-6水平,以及小鼠肝组织中的IL-1β、IL-6 mRNA相对表达量均升高（均为P < 0.05）,且随着再灌注时间的延长呈明显的时间依赖性。与Sham组比较,IRI后各组小鼠肝脏缺血病理学评分和肝细胞凋亡率均升高（均为P < 0.05）。免疫组化结果显示,IRI后HMGB1在肝组织中的表达明显增多,且在2~12 h内随着时间延长而增多。蛋白质印迹法结果显示,在体内和在体外,与Sham组比较,IRI 12 h组HMGB1、Caspase-1和GSDMD蛋白相对表达量均升高;与IRI 12 h组比较,GA+IRI 12 h组HMGB1蛋白相对表达量升高,Caspase-1和GSDMD蛋白相对表达量均降低,差异均有统计学意义（均为P < 0.05）。结论  肝细胞可能通过释放HMGB1激活Caspase-1/GSDMD通路,从而触发肝细胞发生焦亡,导致肝脏IRI,而通过GA抑制HMGB1的胞外释放可减轻肝脏IRI。     

MicroRNA与细胞焦亡在动脉粥样硬化中的作用研究

心血管疾病是危害人类健康的首要原因,而动脉粥样硬化是多种心脑血管疾病的病理基础,近年来针对动脉粥样硬化斑块稳定性诊断和治疗的研究层出不穷。斑块内细胞焦亡的发生直接关系着斑块的稳定性,因此对细胞焦亡的调控对稳定斑块尤为重要。现总结在动脉粥样硬化中新发现的发挥调节作用的microRNAs和一些microRNAs通过调节细胞焦亡在动脉粥样硬化中的作用。     

Pyroptosis modulation by bacterial effector proteins

Pyroptosis is a proinflammatory form of programmed cell death featured with membrane pore formation that causes cellular swelling and allows the release of intracellular inflammatory mediators. This cell death process is elicited by the activation of the pore-forming proteins named gasdermins, and is intricately orchestrated by diverse regulatory factors in mammalian hosts to exert a prompt immune response against infections. However, growing evidence suggests that bacterial pathogens have evolved to regulate host pyroptosis for evading immune clearance and establishing progressive infection. In this review, we highlight current understandings of the functional role and regulatory network of pyroptosis in host antibacterial immunity. Thereafter, we further discuss the latest advances elucidating the mechanisms by which bacterial pathogens modulate pyroptosis through adopting their effector proteins to drive infections. A better understanding of regulatory mechanisms underlying pyroptosis at the interface of host-bacterial interactions will shed new light on the pathogenesis of infectious diseases and contribute to the development of promising therapeutic strategies against bacterial pathogens.     

肿瘤细胞死亡对细胞增殖的双重调控★

细胞增殖和细胞死亡是控制整个生命体生长和发育的基本过程。癌症的特征是两者的异常调节导致细胞不受控制地持续增殖。最初，人们认为细胞死亡是一种常见的肿瘤抑制机制，这一特性被用于癌症治疗。然而，随着对细胞死亡越来越深入的了解，人们发现，死亡细胞可以促进肿瘤细胞增殖，进而导致肿瘤进展。因此，本文就几种不同的调节性细胞死亡（RCD）在肿瘤细胞增殖方面的研究现状进行简要综述，包括细胞凋亡、细胞焦亡以及自噬，并深入了解这些细胞死亡方式作为“双刃剑”如何通过细胞周期影响细胞增殖，以期为癌症的预防和治疗提供理论基础及新的思路。     

Pyroptosis in cardiovascular diseases: Pumping gasdermin on the fire

Pyroptosis is a form of programmed cell death associated with activation of inflammasomes and inflammatory caspases, proteolytic cleavage of gasdermin proteins (forming pores in the plasma membrane), and selective release of proinflammatory mediators. Induction of pyroptosis results in amplification of inflammation, contributing to the pathogenesis of chronic cardiovascular diseases such as atherosclerosis and diabetic cardiomyopathy, and acute cardiovascular events, such as thrombosis and myocardial infarction. While engagement of pyroptosis during sepsis-induced cardiomyopathy and septic shock is expected and well documented, we are just beginning to understand pyroptosis involvement in the pathogenesis of cardiovascular diseases with less defined inflammatory components, such as atrial fibrillation. Due to the danger that pyroptosis represents to cells within the cardiovascular system and the whole organism, multiple levels of pyroptosis regulation have evolved. Those include regulation of inflammasome priming, post-translational modifications of gasdermins, and cellular mechanisms for pore removal. While pyroptosis in macrophages is well characterized as a dramatic pro-inflammatory process, pyroptosis in other cell types within the cardiovascular system displays variable pathways and consequences. Furthermore, different cells and organs engage in local and distant crosstalk and exchange of pyroptosis triggers (oxidized mitochondrial DNA), mediators (IL-1β, S100A8/A9) and antagonists (IL-9). Development of genetic tools, such as Gasdermin D knockout animals, and small molecule inhibitors of pyroptosis will not only help us fully understand the role of pyroptosis in cardiovascular diseases but may result in novel therapeutic approaches inhibiting inflammation and progression of chronic cardiovascular diseases to reduce morbidity and mortality from acute cardiovascular events.     

细胞焦亡与非酒精性脂肪性肝炎“痰湿瘀”病机的微观联系与治疗

细胞焦亡是一种促炎性细胞程序性死亡，在非酒精性脂肪性肝炎发展中扮演重要角色。“痰湿瘀”互结于肝络是非酒精性脂肪性肝炎的核心病机，与细胞焦亡之间可能存在一定的内在联系。因此，通过细胞焦亡与“痰湿瘀”病机的微观联系，探讨中药治疗非酒精性脂肪性肝炎的作用机制，为中药治疗非酒精性脂肪性肝炎的作用机制研究提供新思路。     

Microbial gasdermins: More than a billion years of pyroptotic-like cell death

In the recent past, the concept of immunity has been extended to eukaryotic and prokaryotic microorganisms, like fungi and bacteria. The latest findings have drawn remarkable evolutionary parallels between metazoan and microbial defense-related genes, unveiling a growing number of shared transkingdom components of immune systems. One such component is the gasdermin family of pore-forming proteins – executioners of a highly inflammatory immune cell death program in mammals, termed pyroptosis. Pyroptotic cell death limits the spread of intracellular pathogens by eliminating infected cells and coordinates the broader inflammatory response to infection. The microbial gasdermins have similarly been implicated in defense-related cell death reactions in fungi, bacteria and archaea. Moreover, the discovery of the molecular regulators of gasdermin cytotoxicity in fungi and bacteria, has established additional evolutionary links to mammalian pyroptotic pathways. Here, we focus on the gasdermin proteins in microorganisms and their role in organismal defense and provide perspective on this remarkable case study in comparative immunology.     

Pyroptosis and the cellular consequences of gasdermin pores

The family of gasdermin proteins plays a key role in the host response against external and internal pathogenic signals by mediating the form of inflammatory regulated cell death known as pyroptosis. One of the most well-studied gasdermins within innate immunity is gasdermin D, which is cleaved, oligomerizes, and forms plasma membrane pores. Gasdermin D pores lead to a number of downstream cellular consequences including plasma membrane rupture, or cell lysis. In this review, we describe mechanisms of activation for each of the gasdermins, their cell type specificity and some disease associations. We then discuss downstream consequences of gasdermin pore formation, including cellular mechanisms of membrane repair. Finally, we present some important next steps to better understand pyroptosis and the cellular consequences of gasdermin pore formation.