含pyrin结构域NOD样受体家族3炎性小体的翻译后修饰及其在脓毒症发生发展中的作用

翻译后修饰(post-translational modification, PTM)主要包括磷酸化、泛素化、烷基化、S-亚硝基化和ADP-核糖基化等,能够通过多分子多位点调控含pyrin结构域NOD样受体家族3(NOD-like receptors family pyrin domain containing 3, NLRP3)炎性小体。NLRP3炎性小体激活将造成炎症级联反应不断扩大。而这种炎症反应紊乱是推动脓毒症进展的重要因素。文章详细阐述了NLRP3炎性小体的PTM,并介绍了NLRP3的PTM在脓毒症中的作用,以期干预NLRP3炎性小体的活化,进而调控炎症,为未来脓毒症治疗提供新思路。     

炎性小体的研究进展

炎性小体是由多种蛋白质组成的复合体,分子量约700 kD,此概念由Tschopp研究小组于2002年首次提出[1].炎性小体能够调节胱冬肽酶-1(caspase-1)的活化进而在天然免疫防御的过程中促进细胞因子前体pro-IL-1β和pro-IL-18的切割成熟[2];还能调节caspase-1依赖的形式编程性细胞死亡(pyroptosis)[3],诱导细胞在炎性和应激的病理条件下死亡.目前已发现的炎性小体主要有4种,即NLRP1、NLRP3、IPAF和AIM2炎性小体.已发现的炎性小体一般均含有凋亡相关微粒蛋白(apoptosis-associated speck-like protein containing CARD,ASC)、caspase蛋白酶及一种NOD样受体(NOD-like receptor,NLR)家族蛋白(如NLRP1)或HIN200家族蛋白(如AIM2).炎性小体活性异常与人类的多种遗传疾病或后天疾病发生相关,如遗传性周期发热综合征等[4].     

淀粉样蛋白A在人下肢闭塞性动脉硬化的表达及其激活Nod样受体家族包含pyrin结构域蛋白3炎性体的机制

目的 观察血清淀粉样蛋白A( SAA)、Nod样受体家族包含pyrin结构域蛋白3( NLRP3)、白细胞介素-1β(IL-1β)在人下肢闭塞性动脉硬化症(ASO)中的表达,并通过SAA激活NLRP3炎性体的体外实验分析在ASO中NLRP3炎性体激活的可能机制.方法 免疫组织化学方法检测SAA、NLRP3、IL-1β在ASO血管壁中的表达.SAA处理巨噬细胞,Western blot检测成熟型IL-1β和裂解型Caspase-1,检测细胞中IL-1β前体蛋白、Caspase-1前体蛋白的表达.RNA干扰技术下调单核细胞(THP-1)细胞中NLRP3的表达.免疫荧光技术检测SAA对人巨噬细胞中核因子(NF) -κB p65入核的影响.结果 ASO下肢血管壁中SAA、NLRP3、IL-1β的表达较正常动脉壁上调倍数分别为10.19 ±0.29、7.11 ±0.14、5.06 ±0.15,与正常动脉比较差异有统计学意义(P＜0.01),各蛋白表达呈现出共区域化;SAA处理巨噬细胞,SAA各剂量组(1、2、5、10 mg/L)较对照组比较,NLRP3上调倍数相应为(2.49±0.34、3.19 ±0.22、3.61 ±0.29、4.46±0.20,P＜0.01),Caspase-1p20上调倍数相应为(1.32 ±0.11、4.59±0.28、17.55±1.40、25.69±1.71,P＜0.01),IL-1β p17上调倍数相应为(1.24±0.09、2.48 ±0.22、15.59±0.96、23.57±0.80,P＜0.01),下调THP-1巨噬细胞中的NLRP3表达后,SAA诱导的IL-1β分泌明显减低.SAA可以上调人巨噬细胞中IL-1β前体蛋白的表达,而且被NF-κB特异性阻滞剂Bay1 1-7082所抑制,上调倍数分别为17.64 ±2.07、6.45±1.78,两组比较差异有统计学意义(P＜0.01).免疫荧光显示SAA促进巨噬细胞中NF-κB p65入核.结论 SAA在ASO血管壁中广泛沉积,并上调了NLRP3和IL-1β的表达.SAA可以激活NLRP3炎性体,引起IL-1β的分泌.SAA可以上调IL-1β前体蛋白的表达,从而起到NLRP3炎性体激活致IL-1β分泌的预启动功能.因此在ASO中SAA可能通过激活NLRP3炎性体而促进动脉硬化炎症的发生、发展.     

异氟醚通过NLRP3炎性小体调控炎症微环境的研究

目的探讨异氟醚处理对小胶质细胞NLR家族热蛋白结构域包含蛋白3(NLR family pyrin domain containing 3,NLRP3)炎性小体通路相关炎症微环境的调控作用。方法脂多糖(LPS;1μg·m L-1)预活化小胶质细胞株(BV2)30 min,分别采用异氟醚单独处理和LPS预活化后异氟醚处理6小时。实时荧光定量聚合酶链反应(q RT-PCR)检测NLRP3的m RNA表达量;蛋白免疫印迹(Western-blot)分析NLPR3蛋白表达变化;酶联免疫吸附试验(ELISA)检测炎症因子白介素-1β(interleukin-1β,IL-1β)的分泌情况;CCK8细胞活性试验评估异氟醚处理的毒性作用。结果q RT-PCR及Western-blot结果表明异氟醚单独处理不引起BV2细胞的NLRP3表达变化,LPS预活化后异氟醚处理上调预活化BV2细胞的NLRP3表达;ELISA结果表明异氟醚单独处理不引起BV2细胞IL-1β分泌,LPS预活化后异氟醚处理促进活BV2细胞IL-1β分泌;各组实验条件下BV2细胞活性均无显著改变。结论异氟醚可通过激活NLRP3炎性小体调控小胶质细胞IL-1β的表达。     

NLRP3炎症小体在不孕不育相关生殖疾病中的作用研究进展

NOD样受体家族热蛋白结构域相关蛋白3(NLRP3)炎症小体是一种多聚蛋白质复合体，可被多种信号激活，其激活与体内诸多的免疫和代谢紊乱疾病密切相关。目前已知多囊卵巢综合征(PCOS)、子宫内膜异位症(EMs)以及卵巢早衰(POF)等多种不孕不育相关的生殖疾病均与NLRP3炎症小体的激活有着密切的联系。本文对近年来NLRP3炎症小体在PCOS、EMs、POF中的作用进行综述，并对NLRP3炎症小体在各种生殖疾病中的活化及作用机理进行探讨，以期为不孕不育相关生殖疾病的发病机制研究及临床诊疗提供理论依据。     

乙型肝炎病毒X蛋白通过下调微RNA-223靶向NLRP3炎症小体促进乙型肝炎病毒相关性肾炎足细胞焦亡

目的探讨微RNA(microRNA, miRNA)-223在乙型肝炎病毒(hepatitis B virus, HBV)X蛋白(HBV X protein, HBx)诱导的HBV相关性肾炎(HBV-associated glomerulonephritis, HBV-GN)足细胞焦亡中的潜在功能及相关机制。方法采用人肾足细胞中过表达HBx基因来模拟HBV-GN的发病机制。实时荧光定量PCR和Western印迹分别检测焦亡相关蛋白[核苷酸结合寡聚化结构域样受体蛋白3(nucleotide-binding oligomerization domain-like receptor protein 3, NLRP3)、胱天蛋白酶1(Caspase-1)、凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing a CARD, ASC)]及炎性因子[白细胞介素1β、白细胞介素18]mRNA和蛋白的表达水平;双荧光素酶报告基因实验验证miRNA-223的下游靶标;TUNEL染色和流式细胞术检测细胞焦亡情况;免疫荧光检测足细胞损伤标志物...     

HMGB1促进RSV感染的THP-1单核细胞中NLRP3炎症小体的活化

目的探讨高迁移率族蛋白B1(high-mobility group box 1, HMGB1)对呼吸道合胞病毒(respiratory syncytial virus, RSV)感染的THP-1单核细胞中核苷酸结合域样受体蛋白3(nucleotide-binding oligomerization domain-like receptor protein 3, NLRP3)炎症小体活化的影响。方法常规培养THP-1细胞用于RSV病毒的感染实验, 将培养的THP-1单核细胞分为4组:未感染RSV组、RSV感染组、RSV感染+人重组HMGB1(rHMGB1)组、RSV感染+甘草素组, RSV感染6 h后继续培养48 h, 提取4组细胞总蛋白, Western blot法检测4组THP-1单核细胞的NLRP3、凋亡相关斑点样蛋白(apoptosis-associated speck-like protein containing CARD, ASC)、胱天蛋白酶-1(cysteine aspartate specific protease-1, caspase-1)、IL-1β水平。结果 R...     

NOD样受体蛋白1炎性小体在创伤性中枢神经损伤中的作用

NOD样受体蛋白1（NOD-like receptor protein 1,NLRP1）炎性小体在人体固有免疫反应中发挥着重要作用,可促进半胱氨酸蛋白水解酶（cysteinyl aspartate specific proteinases,Caspases）的活化,进一步激活白介素-18和白介素-1β,同时介导细胞焦亡,NLRP1炎性小体在创伤性中枢神经损伤中发挥着作用,本文就NLRP1炎性小体的结构、NLRP1炎性小体在创伤性中枢神经损伤中的激活以及以NLRP1炎性小体为靶点的治疗等方面进行了综述。     

线粒体-NOD样受体热蛋白结构域相关蛋白3炎症小体通路在急性肺损伤中的作用

NOD样受体热蛋白结构域相关蛋白3(NOD like receptor thermal protein domain associated protein 3, NLRP3)炎症小体是参与炎症反应的一种复合物, 已被证实参与了急性肺损伤(acute lung injury, ALI)的发生、发展, 其激活机制非常复杂, 线粒体活性氧(reactive oxygen species, ROS)以及线粒体DNA(mitochondria DNA, mtDNA)的积累会激活NLRP3炎症小体, 但线粒体在NLRP3炎症小体介导ALI过程中所发挥的作用远不止如此, 阐明临床上各种类型的肺损伤激活线粒体-NLRP3炎症小体通路的完整机制可能为未来治疗相关疾病提供新的思路。文章就NLRP3炎症小体的结构、线粒体-NLRP3炎症小体通路的激活机制及其在ALI中的作用展开综述, 为ALI的临床治疗提供新的思路与策略。     

核苷酸结合寡聚化结构域样受体蛋白3炎性小体在心肺转流大鼠围术期神经认知障碍中的作用

目的探讨核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)炎性小体在心肺转流(CPB)大鼠围术期神经认知障碍(PND)中的作用。方法成年雄性SD大鼠30只,体重350～450 g,进行Morris水迷宫训练5 d后随机分为三组,每组10只:假手术组(S组)、CPB组(C组)和CPB+NLRP3炎性小体抑制剂Ac-YVAD-cmk组(Y组)。S组进行双侧隐动脉、右大隐静脉和右颈内静脉穿刺置管,但不进行CPB;C组穿刺置管后行CPB 60 min;Y组在CPB前30 min给予Ac-YVAD-cmk 8 mg/kg腹腔注射,穿刺置管后行CPB 60 min。术后第3天采用Morris水迷宫实验评估大鼠认知功能,ELISA法检测血浆和海马组织IL-1β和IL-18浓度,Western blot法检测海马组织NLRP3、凋亡相关点样蛋白(ASC)和半胱氨酸蛋白水解酶-1前体(pro-caspase-1)蛋白含量,TUNEL法检测海马组织凋亡情况,计算凋亡指数。结果与S组比较,C组和Y组逃避潜伏期明显延长(P0.05),120 s穿越原平台次数明显减少(P0.05),血浆和海马组织IL-1β和IL-18浓度、NLRP3、ASC和pro-caspase-1蛋白含量以及凋亡指数明显升高(P0.05)。与C组比较,Y组逃避潜伏期明显缩短(P0.05),120 s穿越原平台次数明显增多(P0.05),血浆和海马组织IL-1β和IL-18浓度、NLRP3、ASC和pro-caspase-1蛋白含量以及凋亡指数明显降低(P0.05)。结论 CPB后大鼠PND可能与NLRP3炎性小体的激活有关,使用NLRP3炎性小体抑制剂可减轻大鼠PND的发生。     

Contrast induces kidney epithelial cell apoptosis through NRLP3 inflammasome pathway

Objective To investigate the effect of pyrin domain 3 (NLRP3) inflammasome in the process of contrast induced human kidney cell apoptosis. Methods Human kidney 2 (HK-2) cells were cultured in DMEM-F12 medium with 5% FBS. Cells were divided into control group, Contrast group (O group), NLRP3-siRNA+Iohexol group (si-NLRP3+O group), ASC-siRNA+Iohexol group (si-ASC+O group), and mannitol group (M group). Different concentrations of hypotonic contrast agent were added to HK-2 cell culture plates for 24, 48 and 72 h. Flow cytometry was used to detect apoptosis. NLRP3 and ASC mRNA expressions were detected by RT-PCR. The expressions of NLRP3, ASC, caspase-8/cleaved caspase-8, Bcl-2/Bax, caspase-1/cleaved caspase-1, and caspase-3/cleaved caspase-3 protein were detected by Western blot. The levels of interleukin (IL) 1β and IL-18 in supernatant were detected by ELISA. Results Compared with the control group, the rate of apoptotic cells, as well as the expressions of NLRP3, ASC and cleaved caspase-1 proteins were increased in HK-2 cells of contrast group. The expressions of NLRP3 and ASC mRNA in the contrast group also increased, so did IL-1β and IL-18 levels (all P＜0.05), suggesting that NLRP3 inflammasome in HK-2 cells was activated by contrast. Compared with the control group, the expressions of cleaved caspase-8, Bax and cleaved caspase-3 protein were increased, and the expression of anti-apoptotic protein Bcl-2 was decreased (all P＜0.05). Compared with the contrast group, the rate of apoptotic cells in the si-NLRP3+contrast group and si-ASC+contrast group was significantly decreased; the expression of cleaved caspase-1 was decreased; the expressions of Bax and cleaved caspase-3 were decreased, and Bcl-2 level was increased. The expressions of IL-1β and IL-18 in the supernatant of cells were decreased (all P＜0.05). Conclusion Contrast agent can activate the NLRP3 pathway in HK-2 cells and induce apoptosis, which could be reduced by blocking the NLRP3 pathway.     

NLRP3 inflammasome: A potential therapeutic target to minimize renal ischemia/reperfusion injury during transplantation

Renal transplantation is currently the best treatment option for patients with end-stage kidney disease. Ischemia/reperfusion injury (IRI), which is an inevitable event during renal transplantation, has a profound impact on the function of transplanted kidneys. It has been well demonstrated that innate immune system plays an important role in the process of renal IRI. As a critical component of innate immune system, Nod-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome has received great attention from scientific community over the past decade. The main function of NLRP3 inflammasome is mediating activation of caspase-1 and maturation of interleukin (IL)-1β and IL-18. In this review, we summarize the associated molecular signaling events about NLRP3 inflammasome in renal IRI, and highlight the possibility of targeting NLRP3 inflammasome to minimize renal IRI during transplantation.     

缺氧复氧对H9C2心肌细胞凋亡、自噬和焦亡的影响

目的:探讨缺氧复氧(hypoxia reoxygenation,HR)对H9C2心肌细胞凋亡、自噬和焦亡3种细胞死亡方式的影响。方法:将培养的H9C2心肌细胞按随机数字表法分为正常对照组(Ctrl组)和HR组,其中HR组H9C2心肌细胞在缺氧培养箱中进行氧糖剥夺8h,然后复氧12 h。通过检测细胞培养液中的乳酸脱氢酶(lactate dehydrogenase,LDH)含量及四甲基偶氮唑盐[3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyl tetrazolium bromide,MTT]比色法检测细胞活力来评估细胞损伤情况(每组6孔),Western blot检测(每组9孔)细胞凋亡相关蛋白[天门冬氨酸特异性半胱氨酸蛋白酶(cysteinyl aspartate-specific proteinase,caspase)-3、B细胞淋巴瘤/白血病-2(B-cell lymphoma/leukemia 2,Bcl-2)、Bcl相关蛋白(bcl-associate x protein,Bax)]、自噬相关蛋白[(轻链蛋白3(light chain 3,LC3)Ⅱ/Ⅰ、p62、Beclin-1、磷酸化哺乳动物雷帕霉素靶蛋白(phosphorylated mammalian target of ra-pamycin,p-mTOR)]、焦亡相关蛋白[Nod样受体蛋白-3(nod-like receptor pyrin domain3,NLRP3)、凋亡相关斑点样蛋白(apopto-sis associated speck-like protein,ASC)、caspase-1p20、IL-1β、IL-18]。通过免疫荧光染色进一步评估细胞凋亡、自噬及焦亡情况(每组6孔)。结果:与Ctrl组比较,HR组H9C2心肌细胞HR后细胞活力降低(P<0.05),LDH释放增加(P<0.05),活化的cas-pase-3及Bax的表达上调(P<0.05),Bcl-2表达下降(P<0.05),TUNEL染色显示HR后细胞凋亡显著增加(P<0.05),提示HR后细胞凋亡及损伤增加;而p-mTOR、p62均表达增加(P<0.05),但LC3Ⅱ/Ⅰ和Beclin-1蛋白降低(P<0.05),LC3Ⅱ/Ⅰ免疫荧光染色显示HR后细胞内的自噬小体增加(P<0.05),表明HR后H9C2心肌细胞自噬受到明显抑制;同时炎性小体NLRP3、ASC、cas-pase-1p20蛋白均显著上调(P<0.05),活化的炎症细胞因子IL-1β、IL-18表达增加(P<0.05),提示HR后NLRP3炎性小体活化,细胞焦亡增加。结论:H9C2心肌细胞在HR损伤过程中自噬被抑制,细胞焦亡及凋亡增加。     

Research progress on related mechanisms of uric acid activating NLRP3 inflammasome in chronic kidney disease

Hyperuricemia is an independent risk factor for the progression of chronic kidney disease. High levels of uric acid can lead to a series of pathological conditions, such as gout, urinary stones, inflammation, and uric acid nephropathy. There is a close relationship between uric acid and the NLRP3 inflammasome. NLRP3 inflammasome activation can cause cell damage and even death through endoplasmic reticulum stress, lysosome destruction, mitochondrial dysfunction, and the interaction between the Golgi apparatus and extracellular vesicles. In addition, the NLRP3 inflammasome acts as a molecular platform, triggering the activation of caspase-1 and the lysis of IL-1β, IL-18 and Gasdermin D (GSDMD) through different molecular mechanisms. Cleaved NT-GSDMD forms pores in the cell membrane and triggers pyrophosphorylation, thereby inducing cell death and releasing many intracellular proinflammatory molecules. In recent years, studies have found that hyperuricemia or uric acid crystals can activate NLRP3 inflammasomes, and the activation of NLRP3 inflammasomes plays an important role in kidney disease. This article reviews the possible pathophysiological mechanisms by which uric acid activates inflammasomes and induces kidney damage at the cellular and molecular levels.     

The concept of the inflammasome and its rheumatologic implications

The inflammasome is a proteolytic complex that regulates IL1β and IL-18 secretion in macrophages and dendritic cells. Its plays a vital role in the control of the inflammatory and cellular responses to infectious and danger signals and is an essential part of the innate immune system. Four different inflammasomes have been identified so far, and the NLRP3-inflammasome has been the best-studied in relation to human disease. Activation of the NLRP3-inflammasome by microcrystals, such as monosodium urate (MSU) and basic calcium phosphate (BCP) crystals, leads to IL1β release, which in turn triggers local inflammation. Dysfunction of the NLRP3-inflammasome due to mutations of the NLRP3 gene is the cause of the auto-inflammatory syndrome CAPS. The symptoms and signs of inflammation in both conditions respond to IL1 blockade. IL1 inhibitors have also been used successfully in other idiopathic inflammatory diseases, suggesting that dysregulated inflammasome activity contributes to the pathogenesis of multiple diseases, but the precise underlying mechanisms remain to be identified.     

A Role of the Inflammasome in the Low Storage Capacity of the Abdominal Subcutaneous Adipose Tissue in Obese Adolescents

The innate immune cell sensor leucine-rich–containing family, pyrin domain containing 3 (NLRP3) inflammasome controls the activation of caspase-1, and the release of proinflammatory cytokines interleukin (IL)-1β and IL-18. The NLRP3 inflammasome is implicated in adipose tissue inflammation and the pathogenesis of insulin resistance. Herein, we tested the hypothesis that adipose tissue inflammation and NLRP3 inflammasome are linked to the downregulation of subcutaneous adipose tissue (SAT) adipogenesis/lipogenesis in obese adolescents with altered abdominal fat partitioning. We performed abdominal SAT biopsies on 58 obese adolescents and grouped them by MRI-derived visceral fat to visceral adipose tissue (VAT) plus SAT (VAT/VAT+SAT) ratio (cutoff 0.11). Adolescents with a high VAT/VAT+SAT ratio showed higher SAT macrophage infiltration and higher expression of the NLRP3 inflammasome–related genes (i.e., TLR4, NLRP3, IL1B, and CASP1). The increase in inflammation markers was paralleled by a decrease in genes related to insulin sensitivity (ADIPOQ, GLUT4, PPARG2, and SIRT1) and lipogenesis (SREBP1c, ACC, LPL, and FASN). Furthermore, SAT ceramide concentrations correlated with the expression of CASP1 and IL1B. Infiltration of macrophages and upregulation of the NLRP3 inflammasome together with the associated high ceramide content in the plasma and SAT of obese adolescents with a high VAT/VAT+SAT may contribute to the limited expansion of the subcutaneous abdominal adipose depot and the development of insulin resistance.     

Influence of albumin on expression of NLRP3 inflammasome in renal tubular epithelial cells

Objective To investigate the effect of albumin on expression of NLRP3 inflammasome and its downstream cytokines IL-1β and IL-18 in tubular epithelial cells. Methods Thirty mesangioproliferative glomerulonephritis (MsPGN) patients with different levels of proteinuria were selected, and their renal biopsy samples were stained by PAS and Masson to observe tubular epithelial cells injury and inflammatory cells infiltration. NLRP3, caspase-1, IL-1β and IL-18, as well as different inflammatory cells, were detected by immunohistostaining. In vitro, Western blotting and real-time PCR were employed to detect NLRP3, caspase-1, IL-1β and IL-18 protein and mRNA in HK-2 cells stimulated by bovine serum albumin (BSA) (20 g/L). Results In MsPGN patients with high levels of proteinuria, there were obvious renal tubular epithelial cell injury and inflammatory cells infiltration (all P＜0.05), and the expressions of NLRP3, caspase-1, IL-1β and IL-18 were up-regulated compared to patients with low levels of proteinuria (all P＜0.05). Furthermore, IL-1β and IL-18 expressions were positively correlated with the degree of proteinuria (r=0.836, P＜0.05; r=0.901, P＜0.05). NLRP3, caspase-1, IL-1β and IL-18 protein and mRNA were significantly increased in HK-2 cells stimulated by BSA compared to the control group (all P＜0.05). Conclusions Albumin is able to induce NLRP3 inflammasome activation in tubular epithelial cells, which may be the mechanism of tubulointerstitial injury and inflammation caused by proteinuria.     

青蒿琥酯通过NLRP3炎症小体抑制细胞焦亡减轻大鼠肾缺血-再灌注损伤

目的  探究青蒿琥酯对大鼠肾缺血-再灌注损伤（IRI）的作用及机制。 方法  将25只SD大鼠随机分为假手术组（Sham组）、模型组（IRI组）、低剂量青蒿琥组（ART-L组）、高剂量青蒿琥酯组（ART-H组）和NLRP3炎症小体抑制剂组（INF39组）,每组5只。分析各组大鼠血清肌酐（Scr）、血尿素氮（BUN）水平及肾组织病理损伤情况;检测各组大鼠血清肿瘤坏死因子（TNF）-α、白细胞介素（IL）-6水平;用免疫组织化学染色法检测各组大鼠肾组织IL-1β的表达;免疫荧光染色和蛋白质免疫印迹法检测焦亡相关蛋白的表达。 结果  与Sham组比较,IRI组Scr和BUN水平升高,肾组织损伤较重,炎症因子TNF-α、IL-6、IL-1β表达水平升高,肾损伤分子（KIM）-1及焦亡相关蛋白NOD样受体蛋白3（NLRP3）、半胱氨酸天冬氨酸蛋白酶（Caspase）-1、Gasdermin D（GSDMD）、IL-1β蛋白表达水平均升高;与IRI组比较,ART-L组、ART-H组和INF39组Scr和BUN水平均下降,肾组织损伤均较轻,TNF-α、IL-6、IL-1β表达水平均降低,KIM-1、NLRP3、Caspase-1、GSDMD、IL-1β蛋白表达水平均下降。 结论  青蒿琥酯可抑制NLRP3炎症小体诱导的细胞焦亡,减少肾IRI后焦亡相关蛋白的表达及炎症因子的释放,减轻肾IRI。     

A pan caspase inhibitor decreases caspase-1, IL-1α and IL-1β, and protects against necrosis of cisplatin-treated freshly isolated proximal tubules

Abstract

Caspase-1, IL-1α, and IL-1β are known to be activated in the NLRP3 inflammasome. The inflammasome is activated mostly in inflammatory cells. The presence of inflammasome proteins in proximal tubules (PTs) and the effect of cisplatin-treatment or caspase inhibition on inflammasome proteins in PTs are not known. The aim of this study was to investigate the effect of cisplatin on inflammasome proteins in freshly isolated PTs and also to determine the effect of caspase inhibition on inflammasome proteins and PT injury. PTs were isolated using collagenase digestion and Percoll centrifugation. After recovery period, freshly isolated PTs were incubated with vehicle, 50?µM cisplatin or 50?µM cisplatin plus 50?µM pan caspase inhibitor, QVD-OPH. PTs treated with 50?µM cisplatin showed Propidium Iodide staining indicative of necrosis. Necrotic cells (%) were 2.2 in Vehicle-treated, 37.7 in Cisplatin-treated (p?<?0.05 vs. Vehicle), and 3.3 in QVD-treated (p?<?0.05 vs. Cisplatin). LDH release (%), a marker of cell membrane damage seen in necrosis was 7.1 in Vehicle-treated, 39.7 in Cisplatin-treated (p?<?0.05 vs. Vehicle), and 13.5 in QVD-treated (p?<?0.05 vs. Cisplatin). Caspase-1 activity and active caspase-1 protein (10?kDa) were significantly increased in Cisplatin-treated PTs. NLRP3 was strongly expressed in PTs, but there were no significant changes between groups. Pro-apoptotic BID (22?kDa) was unchanged between groups. IL-1α and IL-1β activity was increased in Cisplatin-treated PTs. QVD-OPH co-treatment decreased caspase-1, IL-1α, and IL-1β. In summary, caspase inhibition decreases caspase-1, IL-1α, and IL-1β but not NLRP3 or BID protein and protects against necrosis in cisplatin-treated freshly isolated PTs.