Diabetic cardiomyopathy:Importance of direct evidence to support the roles of NOD-like receptor protein 3 inflammasome and pyroptosis

Recently,the roles of pyroptosis,a form of cell death induced by activated NODlike receptor protein 3(NLRP3)inflammasome,in the pathogenesis of diabetic cardiomyopathy(DCM)have been extensively investigated.However,most studies have focused mainly on whether diabetes increases the NLRP3 inflammasome and associated pyroptosis in the heart of type 1 or type 2 diabetic rodent models,and whether various medications and natural products prevent the development of DCM,associated with decreased levels of cardiac NLRP3 inflammasome and pyroptosis.The direct link of NLRP3 inflammasome and associated pyroptosis to the pathogenesis of DCM remains unclear based on the limited evidence derived from the available studies,with the approaches of NLRP3 gene silencing or pharmaceutical application of NLRP3 specific inhibitors.We thus emphasize the requirement for more systematic studies that are designed to provide direct evidence to support the link,given that several studies have provided both direct and indirect evidence under specific conditions.This editorial emphasizes that the current investigation should be circumspect in its conclusion,i.e.,not overemphasizing its role in the pathogenesis of DCM with the fact of only significantly increased expression or activation of NLRP3 inflammasome and pyroptosis in the heart of diabetic rodent models.Only clear-cut evidence-based causative roles of NLRP3 inflammasome and pyroptosis in the pathogenesis of DCM can help to develop effective and safe medications for the clinical management of DCM,targeting these biomarkers.

Dietary saturated fatty acid and polyunsaturated fatty acid oppositely affect hepatic NOD-like receptor protein 3 inflammasome through regulating nuclear factor-kappa B activation

AIM: To investigate the effect of different dietary fatty acids on hepatic inflammasome activation.METHODS: Wild-type C57BL/6 mice were fed either a high-fat diet or polyunsaturated fatty acid (PUFA)-enriched diet. Primary hepatocytes were treated with either saturated fatty acids (SFAs) or PUFAs as well as combined with lipopolysaccharide (LPS). The expression of NOD-like receptor protein 3 (NLRP3) inflammasome, peroxisome proliferator-activated receptor-γ and nuclear factor-kappa B (NF-κB) was determined by real-time PCR and Western blot. The activity of Caspase-1 and interleukine-1β production were measured.RESULTS: High-fat diet-induced hepatic steatosis was sufficient to induce and activate hepatic NLRP3 inflammasome. SFA palmitic acid (PA) directly activated NLRP3 inflammasome and increased sensitization to LPS-induced inflammasome activation in hepatocytes. In contrast, PUFA docosahexaenoic acid (DHA) had the potential to inhibit NLRP3 inflammasome expression in hepatocytes and partly abolished LPS-induced NLRP3 inflammasome activation. Furthermore, a high-fat diet increased but PUFA-enriched diet decreased sensitization to LPS-induced hepatic NLRP3 inflammasome activation in vivo. Moreover, PA increased but DHA decreased phosphorylated NF-κB p65 protein expression in hepatocytes.CONCLUSION: Hepatic NLRP3 inflammasome activation played an important role in the development of non-alcoholic fatty liver disease. Dietary SFAs and PUFAs oppositely regulated the activity of NLRP3 inflammasome through direct activation or inhibition of NF-κB.

3'-Deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome

Methamphetamine addiction is a brain disorder characterized by persistent drug-seeking behavior, which has been linked with aberrant synaptic plasticity. An increasing body of evidence suggests that aberrant synaptic plasticity is associated with the activation of the NOD-like receptor family pyrin domain containing-3(NLRP3) inflammasome. 3′-Deoxyadenosin, an active component of the Chinese fungus Cordyceps militaris, has strong anti-inflammatory effects. However, whether 3′-deoxyadenosin attenuates methamphetamine-induced aberrant synaptic plasticity via an NLRP3-mediated inflammatory mechanism remains unclear. We first observed that 3′-deoxyadenosin attenuated conditioned place preference scores in methamphetamine-treated mice and decreased the expression of c-fos in hippocampal neurons. Furthermore, we found that 3′-deoxyadenosin reduced the aberrant potentiation of glutamatergic transmission and restored the methamphetamine-induced impairment of synaptic plasticity. We also found that 3′-deoxyadenosin decreased the expression of NLRP3 and neuronal injury. Importantly, a direct NLRP3 deficiency reduced methamphetamine-induced seeking behavior, attenuated the impaired synaptic plasticity, and prevented neuronal damage. Finally, NLRP3 activation reversed the effect of 3′-deoxyadenosin on behavior and synaptic plasticity, suggesting that the anti-neuroinflammatory mechanism of 3′-deoxyadenosin on aberrant synaptic plasticity reduces methamphetamine-induced seeking behavior. Taken together, 3′-deoxyadenosin alleviates methamphetamine-induced aberrant synaptic plasticity and seeking behavior by inhibiting the NLRP3 inflammasome.

Compatibility with Fructus Ligustri Lucidi Effectively Mitigates Idiosyncratic Liver Injury of Epimedii Folium by Modulating NOD-like Receptor Family Pyrin Domain Containing 3 Inflammasome Activation

Background: Idiosyncratic drug-induced liver injury(IDILI) is a serious side effect of drugs, Epimedii Folium(EF) is unequivocally implicated in idiosyncratic liver injury onset, potentially due to its ability to perturb the NOD-like receptor family pyrin domain containing 3(NLRP3) inflammasome. Fructus Ligustri Lucidi(FLL), a frequently used medicinal combination with EF, has not yet been investigated for its ability to ameliorate EF-associated hepatotoxicity. Aims and Objectives: Study on the mechanism of compatibility of FLL to alleviate liver injury caused by EF. Materials and Methods: Western blot was used to determine the expression of related proteins, ELISA was used to detect the secretion of related inflammatory factors IL-1β, IL-18, IL-6 and TNF-α, liver injury indexes were detected and liver pathological tissue staining was used to evaluate the liver injury. Results: Our results demonstrated that EF exerted a particular augmenting effect on the stimulation of the NLRP3 inflammasome mediated by nigericin or ATP, whereas FLL suppressed the NLRP3 inflammasome stimulation. Furthermore, an equal EF to FLL ratio significantly reduced the stimulatory effects of EF. Moreover, EF has the potential to induce hepatic injury and augment pro-inflammatory cytokine synthesis in rats subjected to LPS. However, when combined with FLL, the detrimental effects of EF were mitigated. Conclusions: FLL possesses the capacity to attenuate EF-associated hepatotoxicity by suppressing EF-triggered NLRP3 inflammasome activation. Thus, FLL holds promise for improving the clinical safety profile of EF, shedding light on the potential of compatibility and detoxification theories in traditional Chinese medicine.

Puerariae Radix protects against ulcerative colitis in mice by inhibiting NLRP3 inflammasome activation

Ulcerative colitis(UC)is a common inflammatory disease of the gastrointestinal tract.Traditional Chinese medicine(TCM)has long been used in Asia as a treatment for UC and Puerariae Radix(PR)is a reliable anti-diarrheal therapy.The aims of this study were to investigate the protective effect of PR using the dextran sulfate sodium salt(DSS)-induced UC model in mice and identify molecular mechanisms of PR action.The chemical constituents of PR via ultra-performance liquid chromatography/tandem mass spectrometry and identified potential PR and UC targets using a network pharmacology(NP)approach were obtained to guide mouse experiments.A total of 180 peaks were identified from PR including 48 flavonoids,46 organic acids,14 amino acids,8 phenols,8 carbohydrates,7 alkaloids,6 coumarins and 43 other constituents.NP results showed that caspase-1 was the most dysregulated of the core genes associated with UC.A PR dose of 0.136 mg/g administered to DSS treated mice reversed weight loss and decreased colon lengths found in UC mice.PR also alleviated intestinal mucosal shedding,inflammatory cell infiltration and mucin loss.PR treatment suppressed upregulation of NOD-like receptor protein 3(NLRP3),cysteinyl aspartate-specific proteases-1(caspase-1),apoptosis-associated speck-like(ASC)and gasdermin D(GSDMD)at both the protein and m RNA expression levels.The addition of a small molecule dual-specificity phosphatase inhibitor NSC 95397 inhibited the positive effects of PR.These results indicated that PR exerts a protective effect on DSS-induced colitis by inhibiting NLRP3 inflammasome activation in mice.

含NOD样受体家族Pyrin域蛋白3/白介素-1β信号通路在脓毒症相关肾损伤中的研究进展

脓毒症相关急性肾损伤(SA-AKI)发病机制复杂,有研究显示,在SA-AKI的发病过程中,NOD样受体家族的NLRP3(NLRP3)被激活,进而增加白细胞介素1β (IL-1β)的产生,介导炎症反应的发展。因此,针对近年NLRP3/IL-1β信号通路在SA-AKI中的研究进展进行了综述,以期为阐述SA-AKI的发病机制提供新的思路,同时也为SA-AKI的诊断和治疗提供了新的策略。

Increased Expression of the NOD-like Receptor Family, Pyrin Domain Containing 3 Inflammasome in Dermatomyositis and Polymyositis is a Potential Contributor to Their Pathogenesis

Background： Dermatomyositis （DM） and polymyositis （PM） are common inflammatory myopathies whose immunopathogenic mechanisms remain poorly understood. The NOD-like receptor family, pyrin domain containing 3 （NLRP3） inflammasome is a type of cytoplasmic multiprotein inflammasome and is responsible for the activation of inflammatory reactivations. Responding to a wide range of exogenous and endogenous microbial or sterile stimuli, NLRP3 inflammasomes can cleave pro-caspase- 1 into active caspase- 1, which processes the pro-infammatory cytokines pro-interleukin （IL）-1 β and pro-IL-18 into active and secreted IL-1β and I L-18. The NLRP3 inflammasome is implicated in infectious and sterile inflammatory diseases. However, it remains unclear whether it is involved in the pathogenesis of DM/PM, which we aim to address in our research. Methods： In this study, 22 DM/PM patients and 24 controls were recruited. The protein and RNA expression of IL-113, IL-18, NLRP3, and caspase-1 in serum and muscle samples were tested and compared between the two groups. Results： The serum IL-1 β and IL-18 levels were significantly higher in DM/PM patients than those in the controls by enzyme linked immunosorbent assay （EL1SA, DM vs. control, 25.02 ± 8.29 ng/ml vs. 16.49 ± 3.30 ng/ml, P 〈 0.001 ; PM vs. control, 26.49±7.79 ng/ml vs. 16.49 ± 3.30 ng/ml, P 〈 0.001）. Moreover, the real-time quantitative reverse transcription-polymerase chain reaction （qRT-PCR） showed that DM/PM patients exhibited higher RNA expression of IL-lβ, IL-18, and NLRP3 in the muscle （for IL-1 β, DM vs. control, P 0.0012, PM vs. control, P = 0.0021 ; for IL- 18, DM vs. control, P = 0.0045, PM vs. control, P 0.0031 ; for NLRP3, DM vs. control, P = 0.0017, PM vs. control, P 0.0006）. Moreover, the protein expression of NLRP3 and caspase- 1 in muscle samples of DM/PM patients were also significantly elevated compared to that in the muscles of the controls. Conclusions： Our findings demonstrate that the NLRP3 inflammasome is implicated in the pathogenesis of DM/PM. High NLRP3 expression led to elevated levels of IL-l13 and IL-18 and could be one of the factors promoting disease progress.

Involvement of NLRP3-inflammasome pathway in noise-induced hearing loss

The inflammasome is a multiprotein oligomer in the cell cytoplasm and is part of the innate immune system.It plays a crucial role in the pathological process of noise-induced hearing loss(NIHL).However,the mechanisms of NLR family pyrin domain containing 3(NLRP3)inflammasome activation in NIHL have not been clearly demonstrated.In this study,miniature pigs were exposed to white noise at 120 dB(A)and auditory brainstem response measurements were used to measure their hearing function.Immunofluorescence staining,confocal laser scanning microscopy,western blot assay,and quantitative reverse transcription-polymerase chain reaction were used to analyze inflammasome-related protein distribution and expression.NLRP3,interleukin-1β,interleukin-18,and cleaved-caspase-1 were highly expressed in the cochlea after 120 dB(A)white noise exposure.Our findings suggest that NLRP3-inflammasomes in the cochlea may be activated after acoustic trauma,which may be an important mechanism of noise-induced hearing loss.

Yemazhui(Herba Eupatorii Lindleyani)ameliorates lipopolysaccharide-induced acute lung injury via modulation of the toll-like receptor 4/nuclear factor kappa-B/nod-like receptor family pyrin domain-containing 3 protein signaling pathway and intestinal flor

OBJECTIVE:To investigate the impact of Yemazhui(Herba Eupatorii Lindleyani,HEL)against lipopolysaccharide(LPS)-induced acute lung injury(ALI)and explore its underlying mechanism in vivo.METHODS:The chemical constituents of HEL were analyzed by ultra-high performance liquid chromatographyquadrupole time-of-flight mass spectrometry method.Then,HEL was found to suppress LPS-induced ALI in vivo.Six-week-old male Sprague-Dawley rats were randomly divided into 6 groups:control,LPS,Dexamethasone(Dex),HEL low dose 6 g/kg(HEL-L),HEL medium dose 18 g/kg(HEL-M)and HEL high dose 54 g/kg(HEL-H)groups.The model rats were intratracheally injected with 3 mg/kg LPS to establish an ALI model.Leukocyte counts,lung wet/dry weight ratio,as well as myeloperoxidase(MPO)activity were determined followed by the detection with hematoxylin and eosin staining,enzyme linked immunosorbent assay,quantitative real time polymerase chain reaction,western blotting,immunohistochemistry,and immunofluorescence.Besides,to explore the effect of HEL on ALI-mediated intestinal flora,we performed 16s rRNA sequencing analysis of intestinal contents.RESULTS:HEL attenuated LPS-induced inflammation in lung tissue and intestinal flora disturbance.Mechanism study indicated that HEL suppressed the lung coefficient and wet/dry weight ratio of LPS-induced ALI in rats,inhibited leukocytes exudation and MPO activity,and improved the pathological injury of lung tissue.In addition,HEL reduced the expression of tumor necrosis factoralpha,interleukin-1beta(IL-1β)and interleukin-6(IL-6)in bronchoalveolar lavage fluid and serum,and inhibited nuclear displacement of nuclear factor kappa-B p65(NF-κBp65).And 18 g/kg HEL also reduced the expression levels of toll-like receptor 4(TLR4),myeloid differentiation factor 88,NF-κBp65,phosphorylated inhibitor kappa B alpha(phospho-IκBα),nod-like receptor family pyrin domain-containing 3 protein(NLRP3),IL-1β,and interleukin-18(IL-18)in lung tissue,and regulated intestinal flora disturbance.CONCLUSIONS:In summary,our findings revealed that HEL has a protective effect on LPS-induced ALI in rats,and its mechanism may be related to inhibiting TLR4/NF-κB/NLRP3 signaling pathway and improving intestinal flora disturbance.

Long noncoding RNA X-inactive specific transcript regulates NLR family pyrin domain containing 3/caspase-1-mediated pyroptosis in diabetic nephropathy

BACKGROUND NLRP3-mediated pyroptosis is recognized as an essential modulator of renal disease pathology.Long noncoding RNAs(lncRNAs)are active participators of diabetic nephropathy(DN).X inactive specific transcript(XIST)expression has been reported to be elevated in the serum of DN patients.AIM To evaluate the mechanism of lncRNA XIST in renal tubular epithelial cell(RTEC)pyroptosis in DN.METHODS A DN rat model was established through streptozotocin injection,and XIST was knocked down by tail vein injection of the lentivirus LV sh-XIST.Renal metabolic and biochemical indices were detected,and pathological changes in the renal tissue were assessed.The expression of indicators related to inflammation and pyroptosis was also detected.High glucose(HG)was used to treat HK2 cells,and cell viability and lactate dehydrogenase(LDH)activity were detected after silencing XIST.The subcellular localization and downstream mechanism of XIST were investigated.Finally,a rescue experiment was carried out to verify that XIST regulates NLR family pyrin domain containing 3(NLRP3)/caspase-1-mediated RTEC pyroptosis through the microRNA-15-5p(miR-15b-5p)/Toll-like receptor 4(TLR4)axis.RESULTS XIST was highly expressed in the DN models.XIST silencing improved renal metabolism and biochemical indices and mitigated renal injury.The expression of inflammation and pyroptosis indicators was significantly increased in DN rats and HG-treated HK2 cells;cell viability was decreased and LDH activity was increased after HGtreatment. Silencing XIST inhibited RTEC pyroptosis by inhibiting NLRP3/caspase-1. Mechanistically,XIST sponged miR-15b-5p to regulate TLR4. Silencing XIST inhibited TLR4 by promotingmiR-15b-5p. miR-15b-5p inhibition or TLR4 overexpression averted the inhibitory effect ofsilencing XIST on HG-induced RTEC pyroptosis.CONCLUSIONSilencing XIST inhibits TLR4 by upregulating miR-15b-5p and ultimately inhibits renal injury inDN by inhibiting NLRP3/caspase-1-mediated RTEC pyroptosis.

Therapeutic interventions target the NLRP3 inflammasome in ulcerative colitis:Comprehensive study

One of the significant health issues in the world is the prevalence of ulcerative colitis(UC).UC is a chronic disorder that mainly affects the colon,beginning with the rectum,and can progress from asymptomatic mild inflammation to extensive inflammation of the entire colon.Understanding the underlying molecular mechanisms of UC pathogenesis emphasizes the need for innovative therapeutic approaches based on identifying molecular targets.Interestingly,in response to cellular injury,the NLR family pyrin domain containing 3(NLRP3)inflammasome is a crucial part of the inflammation and immunological reaction by promoting caspase-1 activation and the release of interleukin-1β.This review discusses the mechanisms of NLRP3 inflammasome activation by various signals and its regulation and impact on UC.

Tranylcypromine upregulates Sestrin 2 expression to ameliorate NLRP3-related noise-induced hearing loss

Noise-induced hearing loss is the primary non-genetic factor contributing to auditory dysfunction.However,there are currently no effective pharmacological interventions for patients with noise-induced hearing loss.Here,we present evidence suggesting that the lysine-specific demethylase 1 inhibitor–tranylcypromine is an otoprotective agent that could be used to treat noise-induced hearing loss,and elucidate its underlying regulatory mechanisms.We established a mouse model of permanent threshold shift hearing loss by exposing the mice to white broadband noise at a sound pressure level of 120 d B for 4 hours.We found that tranylcypromine treatment led to the upregulation of Sestrin2(SESN2)and activation of the autophagy markers light chain 3B and lysosome-associated membrane glycoprotein 1 in the cochleae of mice treated with tranylcypromine.The noise exposure group treated with tranylcypromine showed significantly lower average auditory brainstem response hearing thresholds at click,4,8,and 16 k Hz frequencies compared with the noise exposure group treated with saline.These findings indicate that tranylcypromine treatment resulted in increased SESN2,light chain 3B,and lysosome-associated membrane glycoprotein 1 expression after noise exposure,leading to a reduction in levels of 4-hydroxynonenal and cleaved caspase-3,thereby reducing noise-induced hair cell loss.Additionally,immunoblot analysis demonstrated that treatment with tranylcypromine upregulated SESN2 expression via the autophagy pathway.Tranylcypromine treatment also reduced the production of NOD-like receptor family pyrin domaincontaining 3(NLRP3)production.In conclusion,our results showed that tranylcypromine treatment ameliorated cochlear inflammation by promoting the expression of SESN2,which induced autophagy,thereby restricting NLRP3-related inflammasome signaling,alleviating cochlear hair cell loss,and protecting hearing function.These findings suggest that inhibiting lysine-specific demethylase 1 is a potential therapeutic strategy for preventing hair cell loss and noise-induced hearing loss.

Correlation of NLRP3 polymorphism with inflammasome activity and endothelial damage in patients with acute coronary syndrome

Objective:To study the correlation of Nod-like receptor protein 3 (NLRP3) polymorphism with inflammasome activity and endothelial damage in patients with acute coronary syndrome. Methods:Patients diagnosed with acute coronary syndrome and stable angina pectoris in Mianyang Central Hospital between May 2013 and August 2016 were selected and included in ACS group and SAP group respectively, and healthy volunteers who received physical examination during the same period were selected as control group. Peripheral blood was collected to detect NLRP3 gene rs10754558 loci polymorphism, and serum was separated to determine inflammasome activity indexes and endothelial injury indexes.Results:NLRP3 gene GG genotype and GC genotype constituent ratio of ACS group were significantly higher than those of SAP group and control group while CC genotype constituent ratio was significantly lower than that of SAP group and control group, and serum IL-1β, IL-18, E-selectin, vWF and ET-1 levels were significantly higher than those of SAP group and control group while serum NO level was significantly lower than that of SAP group and control group;serum IL-1β, IL-18, E-selectin, vWF and ET-1 levels in ACS patients with GG genotype and GC genotype were significantly higher than those in patients with CC genotype while NO levels were significantly lower than those in patients with CC genotype, and serum IL-1β, IL-18, E-selectin, vWF and ET-1 levels in ACS patients with GG genotype were significantly higher than those in patients with GC genotype while NO level was significantly lower than that in patients with GC genotype.Conclusions: The increased NLRP3 gene rs10754558 loci alleles G in patients with ACS will increase inflammasome activity and endothelial injury.

Effect of Curcumol on NOD-Like Receptor Thermoprotein Domain 3 Inflammasomes in Liver Fibrosis of Mice

Objective:To investigate the effect of curcumol on NOD-like receptor thermoprotein domain 3(NLRP3)inflammasomes,and analyze the mechanism underlying curcumol against liver fibrosis.Methods:Thirty Kunming mice were divided into a control group,a model group and a curcumol group according to a random number table,10 mice in each group.Mice were intraperitoneally injected with 40% carbon tetrachloride(CCl4:peanut oil,2:3 preparation)at 5 m L/kg for 6 weeks,twice a week,for developing a liver fibrosis model.The mice in the control group were given the same amount of peanut oil,twice a week for 6 weeks.The mice in the curcumol group were given curcumol(30 m L/kg)intragastrically,and the mice in the model and control groups were given the same amount of normal saline,once a day for 6 weeks.Changes in liver structure were observed by hematoxylin and eosin(HE)and Masson staining.Liver function,liver fiber indices,and the expression of interleukin(IL)-10 and tumor necrosis factor-α(TNF-α)levels were determined by automatic biochemical analyzer and enzyme linked immunosorbent assay kit.Immunoblotting and reverse transcription-quantitative PCR(RT-qPCR)were performed to detect the expression of NLRP3 inflammasome-related molecules,TGF-β and collagen.Results:HE and Masson staining results showed that the hepatocytes of the model group were arranged irregularly with pseudo-lobular structure and a large amount of collagen deposition.The mice in the curcumol group had a significant decrease in liver function and liver fibers indices compared with the model group(P<0.05);RT-qPCR and Western blot results reveal that,in the curcumol group,the mRNA and protein expression levels of NLRP3,IL-1β,Caspase 1 and gasdermin D decreased significantly compared with the model group(P<0.05);immunohistochemical results showed that in the curcumol group,the protein expression levels of NLRP3 and IL-1β decreased significantly compared with the model group(P<0.05).Conclusion:A potential anti-liver fibrosis mechanism of curcumol may be associated with the inhibition of NLRP3 inflammasomes and decreasing the downstream inflammatory response.

NLR家族Pyrin域蛋白3炎症小体与妊娠的研究进展

炎症小体是人类天然免疫系统的重要组成部分,参与包括妊娠在内的多种炎症反应,其中NLR家族Pyrin域蛋白3(NLRP3)炎症小体是目前研究最广泛的炎症小体,是宿主防御反应的重要因素,其能够对固有免疫进行调控,各种环境剌激物、多种微生物、内源性或外源性危险信号、病原体和不同的病原相关分子模式(PAMPs)/损伤相关分子模式(DAMPs)都可以激活NLRP3炎症小体释放细胞因子,诱导半胱氨酸天冬氨酸蛋白酶1(caspase-1)依赖的程序性细胞死亡(细胞焦亡),参与多种炎性疾病过程,但对其调控机制尚不明确。近年研究发现NLRP3炎症小体与分娩的发动机制有关,妊娠期间启动了NLRP3炎症小体介导的免疫反应,并且NLRP3炎症小体表达异常与复发性流产、早产、子痫前期和妊娠期糖尿病等妊娠期疾病的发生、发展有关。现就NLRP3炎症小体与妊娠的研究进展进行综述。

维生素D_(3)对小鼠支气管哮喘气道炎症和氧化应激反应的作用及其分子机制

目的探究维生素D_(3)(VitD_(3))在小鼠支气管哮喘气道炎症和氧化应激反应中的作用和相关分子机制。方法将28只雌性C57BL/6小鼠随机分为对照组(Ctrl)和模型组。模型组小鼠采用卵清蛋白(OVA)致敏法建立哮喘模型后,将其分为哮喘(Asthma)组、VitD_(3)处理(Asthma+VitD_(3))组和叉头盒O1(FOXO1)抑制剂AS1842856处理(Asthma+AS)组。测定各组小鼠肺阻力(LR)变化。采用ELISA法检测肺泡灌洗液(BALF)中炎症因子肿瘤坏死因子-α(TNF-α)、白细胞介素(IL)-1β和IL-18的含量。Western blot检测肺组织中FOXO1和NOD样受体热蛋白结构域相关蛋白3(NLRP3)、半胱氨酸天冬氨酸酶-1(Caspase-1)和凋亡斑点蛋白(ASC)的表达水平。结果与Ctrl组相比,Asthma组小鼠的LR升高(P<0.01)。与Asthma组相比,Asthma+VitD_(3)组和Asthma+AS组小鼠的LR降低(P<0.05),Asthma+VitD_(3)组与Asthma+AS组小鼠的LR变化差异无统计学意义。与Ctrl组相比,Asthma组、Asthma+VitD_(3)组和Asthma+AS组小鼠BALF中TNF-α、IL-1β与IL-18含量均增加(P<0.01),肺组织中NLRP3、Caspase-1和ASC蛋白表达水平均升高(P<0.01);与Asthma组相比,Asthma+VitD_(3)组和Asthma+AS组小鼠BALF中上述炎症因子含量均减少(P<0.05),肺组织中NLRP3、FOXO1、Caspase-1和ASC蛋白表达均降低(P<0.05);与Asthma+VitD_(3)组相比,Asthma+AS组中除FOXO1蛋白表达水平升高外(P<0.05),上述其他检测指标差异均无统计学意义。结论VitD_(3)可减轻OVA诱导的小鼠哮喘症状,改善气道炎症程度和降低氧化应激水平,且其机制可能与FOXO1/NLRP3轴的下调有关。

褪黑素通过NF-κB/NLRP3信号抑制子宫内膜异位症的进展机制研究

目的:探讨褪黑素(MEL)对子宫内膜异位症(EMT)进展的抑制作用,以及其对核转录因子κB(NF-κB)/核苷酸结合寡聚化结构域样受体蛋白3(NLRP3)信号的调控机制。方法:通过自体子宫内膜皮下种植法构建EMT大鼠。动物实验模型分假手术组(Sham组,大鼠在造模过程中仅进行子宫片段剪取)和实验处理4组,分别为:模型组(EMT组,大鼠进行自体子宫内膜皮下种植)、褪黑素组(EMT+MEL组,以50 mg/kg的MEL灌胃处理)、EMT+NF-κB信号通路激活剂佛波酯(PMA)组(EMT+PMA组,以5 mg/kg的PMA腹腔注射)、EMT+MEL+PMA组(以50 mg/kg的MEL灌胃处理和5 mg/kg的PMA腹腔注射)。检测各组大鼠子宫内膜异位的质量、血清和腹腔液中肿瘤坏死因子-α(TNF-α)和白细胞介素-6(IL-6)的含量;免疫组化、免疫荧光检测各组样本中髓过氧化物酶(MPO)、血管内皮生长因子(VEGF)的表达;Western blot实验检测各组样本中NF-κB/NLRP3信号通路相关蛋白的表达。结果:与Sham组相比,实验处理4组大鼠中动情周期紊乱的比例、异位子宫内膜的质量、血清以及腹腔液中TNF-α和IL-6的含量、MPO和VEGF的表达及NF-κB/NLRP3信号通路相关蛋白的表达均明显升高,差异均有统计学意义(P<0.05)。与EMT组相比,EMT+MEL组和EMT+MEL+PAM组以上各项指标明显下降,而EMT+PAM组各项指标明显升高;与EMT+MEL组相比,EMT+MEL+PAM组、EMT+PAM组以上各项指标明显升高,以上差异均有统计学意义(P<0.05)。结论:MEL能明显抑制EMT中的炎症反应,抑制EMT的进展,这可能通过抑制NF-κB/NLRP3信号的激活实现的。

衔接蛋白失能同源物2通过抑制NOD样受体热蛋白结构域相关蛋白3对结核性胸膜炎大鼠炎症和氧化应激的影响

目的:探讨衔接蛋白失能同源物2(DAB2)抑制NOD样受体热蛋白结构域相关蛋白3(NLRP3)对结核性胸膜炎大鼠炎症和氧化应激的影响。方法:按照随机数字法将60只SPF级雄性SD大鼠分为四组,每组40只。除正常对照组外,结核性胸膜炎组、DAB2组和pcDNA-NLRP3组进行建模处理,以第2天是否抽出胸腔积液为模型建立成功。正常对照组不注射结核分枝杆菌H37RV悬液,DAB2组建模后第2天静脉注射AAV9-DAB2质粒,每天1次,连续注射7 d,DAB2+pcDNA-NLRP3组在注射AAV9-DAB2质粒500μg/L的同时注射pcDNA-NLRP380μl,正常对照组和结核性胸膜炎组的大鼠尾静脉注射0.9%氯化钠溶液。进行各组呼吸功能指标测定,收集胸腔积液,记录积液量,观察3、5、7 d的胸腔积液粘连性情况,HE染色观察胸膜组织病理学情况,Western blot检测胸膜组织中肿瘤坏死因子-α(TNF-α)、白细胞介素-8(IL-8)、基质金属蛋白酶1(MMP-1)和MMP-9蛋白表达,荧光探针DCFH-DA分析检测活性氧(ROS)的水平。结果:与正常组相比,结核性胸膜炎组的大鼠的胸腔积液和胸膜厚度明显增加,用力肺活量(FVC)、最大呼气流量(PEF)、用力呼气容积(FEV)0.3和FEV0.3/FVC显著降低,TNF-α、IL-8、MMP-1和MMP-9蛋白表达显著升高,基质金属蛋白酶抑制剂(TIMP-1)蛋白表达显著降低,丙二醛(MDA)水平升高,超氧化物歧化酶(SOD)水平降低,ROS累积量明显升高(均P<0.001);与结核性胸膜炎组相比,DAB2组大鼠胸腔积液和胸膜厚度显著降低,FVC、PEF、FEV0.3和FEV0.3/FVC明显升高,DAB2组大鼠胸膜组织中的TNF-α、IL-8、MMP-1和MMP-9蛋白表达明显降低,TIMP-1水平明显升高,MDA水平降低,SOD水平升高,ROS累积量明显降低(均P<0.001);与DAB2组相比,DAB2+pcDNA-NLRP3组大鼠胸腔积液和胸膜厚度明显升高,FVC、PEF、FEV0.3和FEV0.3/FVC明显降低,DAB2+pcDNA-NLRP3组的TNF-α、IL-8、MMP-1和MMP-9蛋白表达明显升高,TIMP-1蛋白表达显著降低,MDA水平明显升高,SOD水平显著降低,ROS累积量显著升高(均P<0.001),各组大鼠在3、5、7 d的胸腔积液粘连性评分比较采用重复测量设计的方差分析,结果显示,不同时间点的胸腔积液粘连性评分比较差异具有统计学意义(均P<0.001);各组胸腔积液粘连性评分比较差异具有统计学意义(均P<0.001);各组胸腔积液粘连性评分变化趋势比较差异有统计学意义(均P<0.001);与模型组相比,DAB2组大鼠的胸膜内和肺间质内血管充血症状减轻,有少量的纤维组织增生,上皮样细胞团以及凝固型坏死也明显减少,淋巴细胞和中性粒细胞浸润也明显减少;与DAB2组相比,DAB2+pcDNA-NLRP3组大鼠的胸膜内和肺间质内血管充血症状加重,出现的纤维组织增生,上皮样细胞团以及凝固型坏死也明显增多,淋巴细胞和中性粒细胞浸润也明显增加。结论:DAB2通过抑制NLRP3的活性促进胸腔积液的吸收,降低胸膜厚度和粘连发生率,降低炎症反应和氧化应激水平,缓解结核性胸膜炎的进展。

A Novel Mutation in the Pyrin Domain of the NOD-like Receptor Family Pyrin Domain Containing Protein 3 in Muckle-Wells Syndrome

Background： Cryopyrin-associated periodic syndrome （CAPS） is a group of rare, heterogeneous autoinflammatory disease characterized by interleukin （IL）-1β-mediated systemic inflammation and clinical symptoms involving skin, joints, central nervous system, and eyes. It encompasses a spectrum of three clinically overlapping autoinflammatory syndromes including familial cold autoinflammatory syndrome, Muckle-Wells syndrome （MWS）, and neonatal-onset multisystem inflammatory disease. CAPS is associated with gain-of-function missense mutations in NOD-like receptor family pyrin domain-containing protein 3 （NLRP3）, the gene encoding NLRP3. Moreover, most mutations leading to MWS occurred in exon 3 ofNLRP3 gene. Here, we reported a novel mutation occurred in exon 1 ofNLRP3 gene in an MWS patient and attempted to explore the pathogenic mechanism. Methods： Genetic sequence analysis of NLRP3 was performed in an MWS patient who presented with periodic lever, arthralgia, and multiform skin lesions. NLRP3 was also analyzed in this patient＇s parents and 50 healthy individuals. Clinical examinations including X-ray examination, skin biopsy, bone marrow aspiration smear, and blood test of C-reactive protein （CRP）, erythrocyte sedimentation rate （ESR）, serum levels oflL-1β, immunoglobulin E （lgE）, antineutrophil cytoplasmic antibodies, antinuclear antibodies, and extractable nuclear antigen were also analyzed. The protein structure of mutant NLRP3 inflammasome was calculated by SWISS-MODEL software. Proteins of wild type and mutant components ofNLRP3 inflammasome were expressed and purified, and the interaction abilities between these proteins were tested by surface plasmon resonance （SPR） assay. Results： X-ray examination showed no abnormality in the patient＇s knees. Laboratory tests indicated an elevation of CRP （233.24 nag/L） and ESR （67 mm/h） when the patient had fever. Serum IL-1β increased to 24.37 pg/ml, and serum lgE was higher than 2500.00 IU/ml. Other blood tests were normal. Bone marrow aspiration smear was normal. A novel point mutation c.92A〉T in exon 1 of NLRP3 gene was identified, which caused a p.D31V mutation in pyrin domain （PYD） of NLRP3. SPR assay showed that this point mutation may strengthen the interaction between the PYD of NLRP3 and the PYD of the apoptosis-associated speck-like protein. The mutation c.92A〉T in exon 1 of the NLRP3 gene was not lbund in the patient＇s parents and 50 healthy individuals. Conclusions： The rnutation c.92A〉T in exon 1 of the NLRP3 gene is a novel mutation associated with MWS. The p.D31V mutation might promote the activation ofNLRP3 inflammasome and induce MWS in this patient.

NLRP3炎症小体在阿尔兹海默症中的作用及潜在治疗靶点

阿尔兹海默症(Alzheimer’s disease,AD)是常见的神经退行性疾病,严重影响患者的生存质量。目前尚无有效的针对性治疗措施。AD发病机制复杂,是环境、遗传和年龄影响因素共同作用的结果。大脑中β-淀粉样蛋白(β-amyloid,Aβ)沉积、微管相关蛋白tau过度磷酸化形成的神经纤维缠结及神经元丢失是AD典型病理特征,大量研究证明,Aβ、tau蛋白聚集诱导核苷酸结合寡聚化结构域样受体含pyrin结构域蛋白3(nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3,NLRP3)炎症小体活化是AD炎性机制的核心环节,且以其和上下游分子为靶点的抑制剂和化合物治疗在细胞和动物模型中均发挥神经保护作用,改善空间记忆功能障碍,但临床疗效和安全性仍待研究。因此,抑制NLRP3炎症小体的活化可能是AD的潜在治疗靶点。本文以NLRP3炎症小体的活化机制和影响因素及与AD关系进行综述,并总结以NLRP3炎症小体为靶点的AD治疗药物,以期为AD等NLRP3炎症小体相关疾病提供新的治疗方向。