硫化氢通过抑制坏死性凋亡对抗高糖引起的H9c2心肌细胞损伤

 目的: 探讨硫化氢(hydrogen sulfide,H₂S)能否通过调控坏死性凋亡(necroptosis)对抗高糖(HG)引起的H9c2心肌细胞损伤。方法: 应用Western blot法检测心肌细胞内能反映坏死性凋亡的RIP3蛋白和cleaved caspase-3蛋白的水平;细胞计数盒测定心肌细胞存活率;双氯荧光素染色荧光显微镜照相法检测细胞内活性氧簇(reactive oxygen species,ROS)水平;罗丹明123染色荧光显微镜照相法测定线粒体膜电位(mitochondrial membrane potential,MMP);Hoechst 33258核染色荧光显微镜照相法测定凋亡细胞的数量。结果: 应用HG(35 mmol/L葡萄糖)处理H9c2心肌细胞3 h、6 h、9 h、12 h和24 h均能明显地上调RIP3蛋白的表达水平,其中24 h时RIP3蛋白水平增加最明显。400μmol/L硫氢化钠(NaHS;为H₂S的供体)预处理或坏死性凋亡的特异性阻断剂necrostatin-1(Nec-1;100μmol/L)共处理心肌细胞均能明显地抑制HG对RIP3蛋白表达的上调作用。此外,NaHS预处理或Nec-1共处理心肌细胞均显著地抑制HG引起的心肌细胞损伤,使细胞存活率升高,ROS生成及MMP丢失减少。另一方面,400μmol/L NaHS预处理心肌细胞能使凋亡细胞数量及cleaved caspase-3表达明显减少。结论: H₂S可通过抑制坏死性凋亡保护心肌细胞,对抗高糖引起的损伤。     

小胶质细胞极化与坏死性凋亡在中枢神经系统疾病中的研究进展

小胶质细胞是中枢神经系统重要的免疫细胞,它可以活化形成两种不同的表型,参与各种病理生理过程。坏死性凋亡是一种近年新发现的细胞程序性死亡方式,兼具凋亡和坏死的部分特性。本文基于小胶质细胞极化和坏死性凋亡的机制,对二者在中枢神经系统疾病中的作用进行综述,以探索疾病可能的治疗思路。     

IL-6促进小鼠小胶质细胞系BV2坏死性凋亡

目的 探究在神经炎性反应中小胶质细胞凋亡的调控机制。方法 脂多糖(lipopolysaccharide, LPS)诱导小鼠小胶质细胞系BV2,构建神经炎性反应细胞模型,使用白介素-6(IL-6)拮抗剂塞妥昔单抗(siltuximab)处理LPS诱导的BV2细胞。CCK-8法检测细胞增殖;流式细胞测量术检测细胞凋亡;ELISA检测IL-6与TNF-α含量;RT-qPCR检测BV2细胞M1极化标志物IL-1β、IFN-γ与M2极化标志物CD206、Arg-1表达;Western blot检测JAK-STAT3信号通路关键蛋白及坏死性凋亡相关蛋白(RIP1)和RIP3表达。结果 LPS诱导后BV2细胞的增殖活力下降,凋亡增加,炎性因子IL-6与TNF-α含量增加(P<0.01)。M1极化标志物IL-1β、IFN-γ表达增加(P<0.01),M2极化标志物CD206、Arg-1表达减少(P<0.01)。JAK-STAT3通路关键蛋白磷酸化增加(P<0.01),RIP1、RIP3蛋白表达增加(P<0.01)。IL-6拮抗剂siltuximab处理细胞后,JAK-ST...     

Necroptosis的调控机制及其在组织及细胞缺血损伤中的作用和意义

Necroptosis不同于坏死和凋亡,具有坏死的细胞形态特点和自噬的活化,并且是主动耗能的,是被一系列信号传导通路所调控的细胞死亡机制.Necroptosis的发现和确认为细胞死亡的逆转和治疗开创了一个新的研究和应用途经.RIP1激酶是调控Necroptosis 形成的关键酶,Necrostatins则是一类小分子化合物,它通过特异性地抑制细胞RIP1激酶而抑制Necroptosis 的形成.     

坏死性凋亡介导高糖引起的人脐静脉内皮细胞损伤

目的:研究坏死性凋亡是否介导高糖(HG)诱导的人脐静脉内皮细胞(human umbilical vein endothelial cells,HUVECs)损伤。方法:CCK-8法检测细胞存活率;Western blot法测定受体相互作用蛋白3(RIP3)、cleaved caspase-3的蛋白水平;罗丹明123染色荧光显微镜照相法检测线粒体膜电位(mitochondrial membrane potential,MMP);双氯荧光素(DCFH-DA)染色荧光显微镜照相法测定胞内活性氧簇(reactive oxygen species,ROS)的水平。结果:应用不同浓度葡萄糖(10、20和40 mmol/L)处理HUVECs 24 h,RIP3的蛋白水平随葡萄糖剂量增加而升高,40 mmol/L时达高峰;应用40 mmol/L葡萄糖处理HUVECs 3 h、6 h、9 h、12 h和24 h能上调RIP3的蛋白水平,于9 h达最高峰;应用20μmol/L凋亡蛋白酶抑制剂Z-VAD-FMK预处理HUVECs 30 min促进RIP3表达;应用100μmol/L坏死性凋亡抑制剂necrostatin-1预处理HUVECs 1 h能抑制HG诱导HUVECs的细胞存活率降低,ROS过度生成及MMP丢失,但能升高cleaved caspase-3的蛋白水平。结论:坏死性凋亡介导高糖引起的人脐静脉内皮细胞损伤,但与内皮细胞凋亡存在负相关。     

巨噬细胞程序性坏死的研究进展北大核心CSCD

程序性坏死是具有独特信号通路并受信号分子调控的有序坏死。巨噬细胞的程序性坏死和其他细胞一样,为胱天蛋白酶(caspase)非依赖性,由受体相互作用蛋白激酶1 (RIP1)和RIP3介导形成死亡诱导信号复合体,进而被诱导产生。巨噬细胞的程序性坏死在多种炎症性疾病中作用显著,阐明巨噬细胞程序性坏死的调控机制及其在炎症相关性疾病发病中的作用,对研究炎症相关性疾病的发病机制及治疗策略具有非常重要的作用。我们主要总结了巨噬细胞程序性坏死的信号通路及其在感染性疾病、动脉粥样硬化、肿瘤和自身免疫性疾病中的作用。     

巨噬细胞程序性坏死的研究进展

程序性坏死是具有独特信号通路并受信号分子调控的有序坏死。巨噬细胞的程序性坏死和其他细胞一样,为胱天蛋白酶(caspase)非依赖性,由受体相互作用蛋白激酶1 (RIP1)和RIP3介导形成死亡诱导信号复合体,进而被诱导产生。巨噬细胞的程序性坏死在多种炎症性疾病中作用显著,阐明巨噬细胞程序性坏死的调控机制及其在炎症相关性疾病发病中的作用,对研究炎症相关性疾病的发病机制及治疗策略具有非常重要的作用。我们主要总结了巨噬细胞程序性坏死的信号通路及其在感染性疾病、动脉粥样硬化、肿瘤和自身免疫性疾病中的作用。     

抑制SHARPIN激活Rip1促进LNCaP-AI细胞坏死性凋亡

目的:探讨SHARPIN对去势抵抗性前列腺癌细胞LNCaP-AI坏死性凋亡关键因子Rip1的调控作用,以及对细胞坏死性凋亡的影响。方法:将LNCaP-AI细胞分为TNF-α+Z-VAD(caspase抑制剂)处理组与TNF-α+Z-VAD+Nec-1(Rip1抑制剂)处理组,应用MTS检测各组细胞的活力,研究坏死性凋亡机制在诱导LNCaP-AI细胞死亡中的作用。将LNCaP-AI细胞分为阴性对照组和SHARPIN干扰(si-SHARPIN)组,RT-qPCR验证抑制效率,通过免疫荧光等技术进一步探讨SHARPIN调控坏死性凋亡的具体分子机制。结果:与对照组相比,TNF-α+Z-VAD处理组的LNCaP-AI细胞活力下降28%(P0.05),而TNF-α+Z-VAD+Nec-1处理组的细胞在Rip1被抑制后,细胞活力无明显改变。在LNCaP-AI细胞中,通过siRNA抑制SHARPIN表达后,Rip1表达水平上调,同时,LNCaP-AI细胞坏死性凋亡比例升高。结论:LNCaP-AI细胞可通过坏死性凋亡机制诱导死亡,下调SHARPIN可能通过激活Rip1增强LNCaP-AI细胞坏死性凋亡。     

坏死性凋亡与肿瘤

坏死性凋亡是不依赖于caspase激活的一种细胞程序性死亡方式,其激活主要依赖于坏死性小体的形成。坏死性凋亡的调控受到多种因素响,RIPK1既可启动坏死性凋亡,也可抑制坏死性凋亡;caspase-8是坏死性凋亡的重要负反馈调节蛋白;CHIP是新发现的坏死性凋亡调控蛋白。坏死性凋亡的触发为对经典凋亡途径抵抗的肿瘤提供了新的治疗策略。     

m6A RNA甲基化修饰在颅脑损伤模型大鼠坏死性凋亡中的作用

背景:哺乳动物中枢神经系统损伤依赖N6-甲基腺苷(m⁶A)的调节,并与坏死性凋亡密切相关。目前在大鼠创伤性颅脑损伤中,m⁶A RNA甲基化修饰与创伤性颅脑损伤坏死性凋亡的关系尚未被研究。目的:探讨m⁶A RNA甲基化修饰与创伤性颅脑损伤大鼠坏死性凋亡的关系,为颅脑损伤坏死性凋亡的发生发展及预后的分子机制提供实验依据。方法:选取SPF级SD雄性大鼠30只,随机分为假手术组、创伤性颅脑损伤组和NSC118218(STAT1抑制剂)组,各10只。后2组通过改良Feeney法建立颅脑损伤模型,假手术组仅暴露脑硬膜,不进行颅脑打击。颅脑损伤6 h后检测各组大鼠大脑皮质炎症因子肿瘤坏死因子ɑ、白细胞介素6、白细胞介素1β、白细胞介素10和高迁移率族蛋白B1表达水平以及脑含水量,检测YTH结构域家族蛋白2、总m⁶A RNA甲基化修饰水平、STAT1和JAK1的表达水平。结果与结论:(1)创伤性颅脑损伤组和NSC118218组炎症因子水平和脑含水量明显高于假手术组,m⁶A RNA甲基化修饰比例...     

RSK3 mediates necroptosis by regulating phosphorylation of RIP3 in rat retinal ganglion cells

Receptor-interacting protein 3 (RIP3) plays an important role in the necroptosis signaling pathway. Our previous studies have shown that the RIP3/mixed lineage kinase domain-like protein (MLKL)-mediated necroptosis occurs in retinal ganglion cell line 5 (RGC-5) following oxygen-glucose deprivation (OGD). However, upstream regulatory pathways of RIP3 are yet to be uncovered. The purpose of the present study was to investigate the role of p90 ribosomal protein S6 kinase 3 (RSK3) in the phosphorylation of RIP3 in RGC-5 cell necroptosis following OGD. Our results showed that expression of RSK3, RIP3, and MLKL was upregulated in necroptosis of RGC-5 after OGD. A computer simulation based on our preliminary results indicated that RSK3 might interact with RIP3, which was subsequently confirmed by co-immunoprecipitation. Further, we found that the application of a specific RSK inhibitor, LJH685, or rsk3 small interfering RNA (siRNA), downregulated the phosphorylation of RIP3. However, the overexpression of rip3 did not affect the expression of RSK3, thereby indicating that RSK3 could be a possible upstream regulator of RIP3 phosphorylation in OGD-induced necroptosis of RGC-5 cells. Moreover, our in vivo results showed that pretreatment with LJH685 before acute high intraocular pressure episodes could reduce the necroptosis of retinal neurons and improve recovery of impaired visual function. Taken together, our findings suggested that RSK3 might work as an upstream regulator of RIP3 phosphorylation during RGC-5 necroptosis.     

Necrostatin-1 Protects Against <Emphasis Type="SmallCaps">d</Emphasis>-Galactosamine and Lipopolysaccharide-Induced Hepatic Injury by Preventing TLR4 and RAGE Signaling

Fulminant hepatic failure (FHF) is a life-threatening clinical syndrome results in massive inflammation and hepatocyte death. Necroptosis is a regulated form of necrotic cell death that is emerging as a crucial control point for inflammatory diseases. The kinases receptor interacting protein (RIP) 1 and RIP3 are known as key modulators of necroptosis. In this study, we investigated the impact of necroptosis in the pathogenesis of FHF and molecular mechanisms, particularly its linkage to damage-associated molecular pattern (DAMP)-mediated pattern recognition receptor (PRR) signaling pathways. Male C57BL/6 mice were given an intraperitoneal injection of necrostatin-1 (Nec-1, RIP1 inhibitor; 1.8 mg/kg; dissolved in 2% dimethyl sulfoxide in phosphate-buffered saline) 1 h before receiving d-galactosamine (GalN; 800 mg/kg)/lipopolysaccharide (LPS; 40 μg/kg). Hepatic RIP1, RIP3 protein expression, their phosphorylation, and RIP1/RIP3 complex formation upregulated in the GalN/LPS group were attenuated by Nec-1. Nec-1 markedly reduced the increases in mortality and serum alanine aminotransferase activity induced by GalN/LPS. Increased serum high mobility group box 1 (HMGB1) and interleukin (IL)-33 release, HMGB1-toll-like receptor 4 and HMGB1-receptor for advanced glycation end products (RAGE) interaction, and nuclear protein expressions of NF-κB and early growth response protein-1 (egr-1) were attenuated by Nec-1. Our finding suggests that necroptosis is responsible for GalN/LPS-induced liver injury through DAMP-activated PRR signaling.     

RIP1-mediated regulation of lymphocyte survival and death responses

RIP1 is an adaptor serine/threonine kinase associated with the signaling complex of death receptors (DRs) including Fas, TNFR1, and TRAIL-Rs which can initiate apoptosis. While DRs are dispensable throughout development, RIP1 deletion results in perinatal lethality. The developmental defect caused by absence of RIP1 remains unexplained. In previous studies, RIP1-deficient hematopoietic progenitors failed to reconstitute the T cell compartment and our recent data indicate a new role for RIP1 in TCR-induced activation of the pro-survival NF-κB pathway. Here, we show that RIP1 is also critical for B cell development. In addition, RIP1(-/-) B cells stimulated through LPS/TLR4 are impaired in NF-κB activation but have no major defect in the Akt pathway. Recently, RIP1 has also emerged as a critical player in necrosis-like death, necroptosis, in various cell lines. We have demonstrated that RIP1 deficiency can reverse the embryonic and T cell proliferation defects in mice lacking FADD, a caspase adaptor protein, which indicates a potential role for RIP1 in mediating in vivo necroptosis. We provide an overview and discussion of the accumulating data revealing insights into the diverse functions of RIP1 in survival and death signaling in lymphocytes.     

RIP1在细胞程序性死亡中作用的研究进展

近期研究发现受体相互作用蛋白（receptor—interacting protein,RIP）是细胞生存和死亡的重要交叉点,在细胞的凋亡与存活、程序性坏死等过程中发挥着关键性的作用。RIP1为RIP家族中的第一个成员,是一种重要的细胞信号转导调控分子。RIP1的结构与生物学功能及在细胞程序性死亡中的作用具有重要意义。     

Manipulation of necroptosis by Porphyromonas gingivalis in periodontitis development

To eliminate invading pathogens and keep homeostasis, host employs multiple approaches such as the non-inflammation associated-apoptosis, inflammation associated-necroptosis and pyroptosis, etc. Necroptosis is known as a highly pro-inflammatory form of cell death due to the release of massive damage-associated molecular patterns (DAMPs). For the first time, we reported that Porphyromonas gingivalis induced cellular necroptosis through receptor-interacting protein 1 (RIP1)/RIP3/mixed lineage kinase domain-like (MLKL) signaling pathway in monocytes. Necroptosis in THP-1 cells was induced by MLKL phosphorylation in vitro. P. gingivalis treated-THP-1 cells exhibited lower cell death rate with pretreatment of inhibitors RIP1 and MLKL, accompanied with attenuated TNF-α and IL-6 expressions. Moreover, the necroptosis risk was also reduced via gene silencing by RIP3 or MLKL in the P. gingivalis treated-THP-1 cell lines. We further explored P. gingivalis-induced necroptosis in animal models in vivo. Firstly, C57BL/6 mice were injected with P. gingivalis in the subcutaneous chamber model. Animals pretreated with MLKL inhibitor exhibited significantly enhanced P. gingivalis clearance; in addition, levels of TNF-α and IL-6 were notably decreased by 60% via MLKL inhibition. Secondly, P. gingivalis-induced periodontitis was utilized to investigate necroptosis related-periodontopathogensis. Positive staining of phosphorylated MLKL in mice periodontitis biopsies was detected to a higher degree, while larger amount of alveolar bone loss was observed in MLKL (−) group comparing to those in the MLKL (+) group. These findings may suggest that P. gingivalis play essential roles in necroptosis process during periodontitis, and our research may shed light on the further work on the related periodontopathogenesis investigation.     

The adaptor protein FADD protects epidermal keratinocytes from necroptosis in vivo and prevents skin inflammation

Epidermal keratinocytes provide an essential structural and immunological barrier forming the first line of defense against potentially pathogenic microorganisms. Mechanisms regulating barrier integrity and innate immune responses in the epidermis are important for the maintenance of skin immune homeostasis and the pathogenesis of inflammatory skin diseases. Here, we show that epidermal keratinocyte-restricted deficiency of the adaptor protein FADD (FADD(E-KO)) induced severe inflammatory skin lesions in mice. The development of skin inflammation in FADD(E-KO) mice was triggered by RIP kinase 3 (RIP3)-mediated programmed necrosis (termed necroptosis) of FADD-deficient keratinocytes, which was partly dependent on the deubiquitinating enzyme CYLD and tumor necrosis factor (TNF)-TNF receptor 1 signaling. Collectively, our findings provide an in?vivo experimental paradigm that regulation of necroptosis in keratinocytes is important for the maintenance of immune homeostasis and the prevention of chronic inflammation in the skin.     

Programmed necrosis: backup to and competitor with apoptosis in the immune system

Programmed cell death is essential for the development and maintenance of the immune system and its responses to exogenous and endogenous stimuli. Studies have demonstrated that in addition to caspase-dependent apoptosis, necrosis dependent on the kinases RIP1 and RIP3 (also called necroptosis) is a major programmed cell-death pathway in development and immunity. These two programmed cell-death pathways may suppress each other, and necroptosis also serves as an alternative when caspase-dependent apoptosis is inhibited or absent. Here we summarize recent advancements that have identified the molecular mechanisms that underlie necroptosis and explore the mechanisms that regulate the interplay between apoptosis and necroptosis.     

RIP3: a molecular switch for necrosis and inflammation

The receptor-interacting protein kinase 3 (RIP3/RIPK3) has emerged as a critical regulator of programmed necrosis/necroptosis, an inflammatory form of cell death with important functions in pathogen-induced and sterile inflammation. RIP3 activation is tightly regulated by phosphorylation, ubiquitination, and caspase-mediated cleavage. These post-translational modifications coordinately regulate the assembly of a macromolecular signaling complex termed the necrosome. Recently, several reports indicate that RIP3 can promote inflammation independent of its pronecrotic activity. Here, we review our current understanding of the mechanisms that drive RIP3-dependent necrosis and its role in different inflammatory diseases.