依达拉奉对大鼠坐骨神经损伤后脊髓脂质过氧化的影响

目的:探讨自由基清除剂依达拉奉对坐骨神经损伤后神经功能及脊髓脂质过氧化反应的影响.方法:Wistar大鼠48只,随机分为3组:坐骨神经挤压伤组、依达拉奉治疗组、假手术组.分别于7、14、21、28 d检测各组大鼠坐骨神经功能指数(SFI)、脊髓内过氧化物歧化酶(SOD)和丙二醛(MDA)的变化.结果:伤后各组大鼠SFI均降低,挤压伤组大鼠SFI较依达拉奉治疗组低(P<0.05),神经功能恢复较治疗组缓慢.伤后挤压伤组大鼠脊髓内SOD活性升高,依达拉奉治疗组大鼠脊髓内SOD活性与假手术组相比升高不明显(P>0.05).伤后挤压伤组大鼠脊髓内MDA含量上升明显,依达拉奉治疗组大鼠脊髓内MDA含量在各个时间点均显著低于挤压伤组大鼠脊髓内MDA含量(P相似文献   

NLRP3 inflammasome activation in murine alveolar macrophages and related lung pathology is associated with MWCNT nickel contamination

Multi-walled carbon nanotubes (MWCNT) have been reported to cause lung pathologies in multiple studies. However, the mechanism responsible for the bioactivity has not been determined. This study used nine different well-characterized MWCNT and examined the outcomes in vitro and in vivo. MWCNT, from a variety of sources that differed primarily in overall purity and metal contaminants, were examined for their effects in vitro (toxicity and NLRP3 inflammasome activation using primary alveolar macrophages isolated from C57Bl/6 mice). In addition, in vivo exposures were conducted to determine the inflammatory and pathogenic potency. The particles produced a differential magnitude of responses, both in vivo and in vitro, that was associated most strongly with nickel contamination on the particle. Furthermore, the mechanism of action for the Ni-contaminated particles was in their ability to disrupt macrophage phagolysosomes, which resulted in NLRP3 activation and subsequent cytokine release associated with prolonged inflammation and lung pathology.     

Adenovirus-delivered angiopoietin-1 ameliorates phosgene-induced acute lung injury via inhibition of NLRP3 inflammasome activation

Objective: Angiopoietin-1 (Ang1) is reported to have the ability to attenuate endothelial permeability and inflammation during the stress condition and is considered to play a critical role in vascular stabilization. The aim of this study was to investigate the mechanisms involved in the protective effects of adenovirus-delivered Ang1 in phosgene-induced acute lung injury (ALI).

Methods: ALI was induced in rats by phosgene exposure at 8.33?g/m³ for 5?min, followed by an intravenous injection of adenovirus-Ang1 (Ad/Ang1). The histologic changes of the lung were evaluated with H&;E staining. The levels of cytokines in the serum and bronchoalveolar lavage fluid (BALF) were determined by ELISA. NLRP3 inflammasome activation was assessed with immunohistochemistry, RT-PCR, Western blotting and TUNEL staining.

Results: Histologic analyses suggested that reduced severity in phosgene-induced ALI with Ad/Ang1 treatment. Reduced levels of IL-1β, IL-18 and IL-33 were found in both serum and BALF samples from Ad/Ang1-treated ALI rats induced by phosgene. Moreover, immunohistochemistry analysis revealed that Ad/Ang1 treatment inhibited the NLRP3 inflammasome activation. Decreased mRNA and protein levels of NLRP3 and caspase-1 were found in phosgene-exposed rats treated with Ad/Ang1. In addition, TUNEL staining indicated a decrease in pyroptosis in phosgene-exposed rats treated with Ad/Ang1.

Conclusions: Ang1 exerts beneficial effects on phosgene-induced lung injury via inhibition of NLRP3 inflammasome activation. Disruption of NLRP3 inflammasome activation might be served as therapeutic modality for the treatment of phosgene-induced ALI.     

NLRP3 inflammasome activation is associated with PM2.5‐induced cardiac functional and pathological injury in mice

Growing evidences indicate that inflammation induced by PM_2.5 exposure has been considered as a major driving force for the development of cardiovascular diseases. However, the mechanisms underlying PM_2.5‐induced cardiac injury remain unclear. This study aims to investigate the role of NLRP3 inflammasome in PM_2.5‐induced cardiac functional and pathological injury in mice. In this study, BALB/c mice were intratracheally instilled with PM_2.5 suspension (4.0 mg/kg BW) for 5 days to set up a cardiac injury model, which was evaluated by electrocardiogram monitoring, HE and Masson staining. Then, the effects of PM_2.5 on the expression of α‐SMA, NLRP3, IL‐1β, and IL‐18 proteins and the activation of caspase‐1 and IL‐1β were investigated. The results showed that PM_2.5 exposure induced characteristic abnormal ECG changes such as the abnormality of heart rhythm, tachycardia, and T‐wave reduction. Inflammatory cell infiltration and fibrosis were observed in the heart tissues of PM_2.5‐exposed mice. Meanwhile, PM_2.5 exposure increased the expression of α‐SMA. And, NLRP3 activation‐associated proteins of NLRP3, IL‐1β, IL‐18, Cleaved caspase‐1 p10, and Cleaved IL‐1β were upregulated in heart tissue of PM_2.5‐induced mice. In summary, PM_2.5 exposure could induce cardiac functional and pathological injury, which may be associated with the activation of NLRP3 inflammasome.     

MicroRNA-30c attenuates contrast-induced acute kidney injury by suppressing NLRP3 inflammasome

BackgroundsContrast-induced acute kidney injury (CIAKI) is the third most common cause of hospital-acquired AKI. It has been demonstrated that microRNA-30c (miR-30c) was upregulated in the CIAKI. However, the underlying mechanism remain unclear.MethodsThe CIAKI was induced in miniature pig. The expression profile of miR-30c in the kidney was evaluated by qPCR. The pathways regulated by miR-30c was identified by qPCR and western blot on renal tubular epithelial cells isolated from miniature pig. Finally, the potential therapeutic application of targeting miR-30c was assessed in the pig model of CIAKI.ResultsThe miR-30c was up-regulated in miniature pig with CIAKI. The miR-30c suppressed cell apoptosis, expression of NLRP3, the secretion of IL-1β and caspase-1 p10 on renal cells stimulated by iohexol in vitro. In the pig model, miR-30c inhibited the CIAKI development.ConclusionOur data demonstrated that the miR-30c induced by CIAKI could suppress cell apoptosis and kidney injury via targeting NLRP3. Therefore, targeting miR-30c might be a novel therapeutic candidate for CIAKI treatment and prevention.     

Atractylodin attenuates lipopolysaccharide-induced acute lung injury by inhibiting NLRP3 inflammasome and TLR4 pathways

Acute lung injury (ALI) arises from uncontrolled pulmonary inflammation with high mortality rates. Atractylodin (Atr) is a polyethylene alkynes and has been reported to possess anti-inflammation effect. Thus, we aimed to investigate the protective effect of Atr on lipopolysaccharide (LPS)-induced inflammatory responses ALI. The results indicated that Atr treatment not only significantly attenuated LPS-stimulated histopathological changes but also lessened the myeloperoxidase (MPO) activity, the wet-to-dry weight ratio of the lungs, protein leakage and infiltration of inflammatory cells. Moreover, Atr inhibited the tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-1β and monocyte chemoattractant protein (MCP)-1 secretion in BALF. Further study demonstrated that such inhibitory effects of Atr were due to suppression of nucleotide-binding domain-(NOD-) like receptor protein 3 (NLRP3) inflammasome and toll like receptor 4 (TLR4) activation, likely contributing to its anti-inflammatory effects. Collectively, these findings suggest that Atr may be an effective candidate for alleviating LPS-induced inflammatory responses.     

白藜芦醇对急性肝损伤小鼠NLRP3炎性体表达的影响

目的观察白藜芦醇对急性肝损伤(acute liver injury,ALI)小鼠Nod样受体家族3(Nod-like receptor 3,NLRP3)炎性体表达的影响,探讨白藜芦醇对ALI的保护作用及其机制。方法本实验采用四氯化碳制作ALI小鼠模型。将雄性ICR小鼠随机分成正常对照组、模型组、白藜芦醇低、中、高剂量组及阳性对照组,每组7只。白藜芦醇低、中、高剂量组及阳性对照组于造模前24 h及1 h分别腹腔注射剂量为10、20及30 mg/kg的白藜芦醇或剂量为100 mg/kg的乙酰半胱氨酸,对照组及模型组在相应时间点腹腔注射等量生理盐水,造模时模型组及各药物干预组采用腹腔注射5%四氯化碳,对照组腹腔注射等量橄榄油。采用蛋白质印迹(Western blot,WB)法测定小鼠肝组织NLRP3、凋亡相关微粒蛋白(apoptosis-associated speck-like protein contain,ASC)、炎性半胱天冬酶-1(caspase-1)蛋白,酶联免疫吸附测定(enzyme linked immunosorbent assay,ELISA)法检测炎症因子白介素(interleukin,IL)-1β及IL-18,全自动生化分析仪测定小鼠肝功能,病理组织学观察肝脏损伤情况及其程度。结果模型组小鼠谷丙转氨酶(alanine aminotransferase,ALT)及谷草转氨酶(aspartate aminotransferase,AST)水平高于正常对照组(P<0.01);白藜芦醇各剂量组及阳性对照组小鼠ALT及AST水平均低于模型组(P<0.01)。模型组小鼠肝脏炎症积分及损伤面积均高于正常对照组(P<0.01);白藜芦醇各剂量组及阳性对照组小鼠肝脏炎症积分及损伤面积均低于模型组(P<0.05或P<0.01)。模型组小鼠NLRP3、ASC、caspase-1、IL-1β及IL-18表达高于正常对照组(P<0.01);白藜芦醇各剂量组及阳性对照组小鼠NLRP3、ASC、caspase-1、IL-1β及IL-18表达均低于模型组(P<0.05或P<0.01)。病理组织切片显示,模型组小鼠肝细胞结构表现为胞浆疏松,小叶内坏死灶较多,坏死灶中可见中性粒细胞浸润;白藜芦醇各剂量组及阳性对照组小叶内坏死灶及中性粒细胞浸润等改变较模型组减少,肝细胞的受损面积较小。结论白藜芦醇可以显著减轻四氯化碳诱导的ALI,其机制可能与抑制NLRP3炎性体活化及其下游炎症级联反应有关。     

Cyclic helix B peptide alleviates sepsis-induced acute lung injury by downregulating NLRP3 inflammasome activation in alveolar macrophages

Acute lung injury (ALI) exhibits high clinical morbidity and mortality rates. Our previous study has indicated that the novel proteolysis-resistant cyclic helix B peptide (CHBP) exerts an anti-inflammatory effect in mice with AKI. In the present study, we evaluated the effect of CHBP in an in vivo sepsis-induced ALI model and in vitro using lipopolysaccharide (LPS) and ATP stimulated bone marrow-derived macrophages (BMDMs). For in vivo experiments, mice were randomly divided into three groups: 1) sham; 2) LPS; and 3) LPS + CHBP (n = 6). All relevant data were collected after 18 h. Following CHBP treatment, the lung function of the mice was significantly improved compared to the LPS group. CHBP administration inhibited interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α production at both the protein and mRNA levels. Additionally, following CHBP treatment, the population of pulmonary macrophages decreased. Simultaneously, the proportion of caspase-1-activated alveolar macrophages was also decreased after CHBP treatment. The protein levels of NLRP3 and cleaved caspase-1 were attenuated in the lung tissue following CHBP treatment. In in vitro experiments, CHBP treatment decreased NLRP3 inflammasome expression and downstream IL-1β secretion, consistent with the in vivo results. In addition, CHBP reversed nuclear factor (NF)-κB and I-κB phosphorylation with a significant dose-dependent effect. Therefore, these findings suggest the potential of CHBP as a therapeutic agent in sepsis-induced ALI owing to inhibition of the NLRP3 inflammasome via the NF-κB pathway in macrophages.     

NLRP3炎性小体与糖尿病心肌病的发生发展

糖尿病心肌病(DCM)是糖尿病特异性心脏并发症,可独立于冠状动脉疾病、高血压或瓣膜性心脏病发生。目前公认的发病机制包括高血糖、蛋白非酶糖基化、氧化应激、钙离子转运异常等,其中炎症是导致左心室舒张功能障碍的独立因素。NLRP3是最常见的炎性小体,可诱导分泌IL-1β、IL-18等促炎细胞因子以及介导细胞焦亡。DCM发生时NLRP3表达上调,加剧胰岛β细胞功能受损、心肌损伤、心肌纤维化进程。已有研究证实,中药可通过抑制NLRP3炎性小体的启动和活化,以及其下游基因的表达,改善DCM心脏功能。本文就NLRP3炎性小体参与DCM发生及中药干预作用进行综述。     

NLRP3炎症小体与心房颤动的研究进展

心房颤动（AF）是临床最常见的快速性心律失常,其发生机制尚未完全阐明,而炎症反应增强常与AF的发生发展相关。核苷酸结合寡聚化结构域受体蛋白3（NLRP3）作为近年研究最为广泛最具特征性的炎症小体,参与诸多非感染性炎性反应。有证据显示其与心房重构、心肌纤维化密切相关,以此入手可为阐明AF的上游机制提供新的理论基础和研究靶点。本文简述了NLRP3的特性及信号传导途径,从基础和临床研究两方面总结了NLRP3与AF的相关性,并对未来NLRP3拮抗剂的应用作出了展望。     

炎症小体在纤维化疾病中作用的研究进展

炎症小体为多种蛋白质组成的复合体,其激活和随后的炎性细胞因子分泌对于先天免疫防御是必需的,并且在适应性免疫应答中也发挥重要作用。纤维化是慢性炎症发展的最后阶段,是细胞外基质过度沉积的结果,导致组织结构损伤和器官功能出现障碍。近年来,报道了许多炎症小体在纤维化疾病中的研究。该文对炎症小体在纤维化疾病中的作用进行综述,以促进炎症小体相关机制及药物的研究与开发。     

Quercetin attenuates NLRP3 inflammasome activation and apoptosis to protect INH-induced liver injury via regulating SIRT1 pathway

Severe hepatotoxicity greatly limits the clinical application of the first-line anti-tuberculosis drug isoniazid(INH). Quercetin(Que) has multiple pharmacological properties, and is regarded as a potential protective agent against a variety of organ injuries. However, the exact effect of quercetin on INH-induced hepatotoxicity and the underlying mechanisms are not yet completely understood. In this study, liver injury models were established in rats and L02 cells to reveal the protective effect of Que on INH-induced hepatotoxicity and the relevant mechanism. The in vivo results indicated that Que pretreatment reduced the level of ALT/AST, improved the liver histopathological changes and substantially mitigated apoptosis in rats. In vitro, it evidently relieved INH-induced cell viability loss and apoptosis in L02 cells. Furthermore, the studies on mechanisms elucidated that Que remarkably elevated the expression of SIRT1 and suppressed NLRP3 inflammasome activation. Meanwhile, Que significantly inhibited the level of tumor suppressor P53, Bax, cleaved-cas3 expressionl and increased Bcl-2 expression to reduce apoptosis in vivo and in vitro. However, SIRT1 inhibitor EX527 reversed the suppression of Que on NLRP3 inflammasome activation and the protection of Que on rat liver injury and cell apoptosis. In short, our findings showed that Que exhibited protective effects against INH-induced liver damage via inhibiting the activation of NLRP3 inflammasome and apoptosis in a SIRT-dependent manner.     

Synthesis and biological evaluation of α,β-unsaturated carbonyl compounds targeting the NLRP3 inflammasome

A series of α,β-unsaturated ketone derivatives were synthesized, and their anti-inflammatory activity toward NLRP3 inflammasome was evaluated in vitro. Several compounds were identified as anti-inflammatory agents, among which compound A21 exhibited potent anti-inflammatory activity in a dose-dependent manner with an IC₅₀ of 0.95 μM. Moreover, a preliminary structure-activity relationship was also summarized.     

Acetylase inhibitor SI-2 is a potent anti-inflammatory agent by inhibiting NLRP3 inflammasome activation

Aberrant activation of Nod-like receptor family pyrin domain-containing-3 (NLRP3) inflammasome is implicated in a variety of inflammatory diseases. Targeting NLRP3 inflammasome represents a promising therapy to cure such diseases. We and others recently demonstrated that acetylation of NLRP3 promotes the inflammasome activity and also suggested lysine acetyltransferases inhibitors could be a kind of promising agents for treating NLRP3 associated disorders. In this study, by searching for kinds of lysine acetyltransferases inhibitors, we showed that SI-2 hydrochloride (SI-2), a specific inhibitor of lysine acetyltransferase KAT13B (lysine acetyltransferases 13B), specifically blocks NLRP3 inflammasome activation both in mice in vivo and in human cells ex vivo. Intriguingly, SI-2 does not affect the acetylation of NLRP3. Instead, it disrupts the interaction between NLRP3 and adaptor apoptosis-associated speck-like protein containing CARD (ASC), then blocks the formation of ASC speck. Thus, our study identified a specific inhibitor for NLRP3 inflammasome and suggested SI-2 as a potential inhibitory agent for the therapy of NLRP3-driven diseases.     

Glyburide attenuates ozone‐induced pulmonary inflammation and injury by blocking the NLRP3 inflammasome

Glyburide is a classic antidiabetic drug that is dominant in inflammation regulation, but its specific role in ozone‐induced lung inflammation and injury remains unclear. In order to investigate whether glyburide prevents ozone‐induced pulmonary inflammation and its mechanism, C57BL/6 mice were intratracheally pre‐instilled with glyburide or the vehicle 1 hour before ozone (1 ppm, 3 hours) or filtered air exposure. After 24 hours, the total inflammatory cells and total protein in bronchoalveolar lavage fluid (BALF) were detected. The pathological alternations in lung tissues were evaluated by HE staining. The expression of NLRP3, interleukin‐1β (IL‐1β), and IL‐18 protein in lung tissues was detected by immunohistochemistry. Western blotting was used to examine the levels of caspase‐1 p10 and active IL‐1β protein. Levels of IL‐1β and IL‐18 in BALF were measured using ELISA kits. Glyburide treatment decreased the total cells in BALF, the inflammatory score, and the mean linear intercept induced by ozone in lung tissues. In addition, glyburide inhibited the expression of NLRP3, IL‐18, and IL‐1β protein in lung tissues, and also suppressed NLRP3 inflammasome activation, including caspase‐1 p10, active IL‐1β protein in lung tissues, IL‐1β, and IL‐18 in BALF. These results demonstrate that glyburide effectively attenuates ozone‐induced pulmonary inflammation and injury via blocking the NLRP3 inflammasome.     

Salidroside protects mice against CCl4-induced acute liver injury via down-regulating CYP2E1 expression and inhibiting NLRP3 inflammasome activation

Salidroside (Sal), a natural phenolic compound isolated from Rhodiola sachalinensis, has been utilized as anti-inflammatory and antioxidant for centuries, however, its effects against liver injury and the underlying mechanisms are unclear. This study was designed to evaluate the protective effects and underlying mechanisms of Sal on carbon tetrachloride (CCl4)-induced acute liver injury (ALI) in mice. C57BL/6 mice were pretreated with Sal before CCl4 injection, the serum and liver tissue were collected to evaluate liver damage and molecular indices. The results showed that Sal pretreatment dose-dependently attenuated CCl4-induced acute liver injury, as indicated by lowering the activities of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT), and inhibiting hepatic pathological damage and apoptosis. In addition, Sal alleviated CCl4-primed oxidative stress and inflammatory response by restoring hepatic glutathione (GSH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and inhibiting cytokines. Finally, Sal also down-regulated the expression of cytochrome P4502E1 (CYP2E1), and Nod-like receptor protein 3 (NLRP3) inflammasome activation in the liver of mice by CCl4. Our study demonstrates that Sal exerts its hepatoprotective effects on ALI through its antioxidant and anti-inflammatory effects, which might be mediated by down-regulating CYP2E1 expression and inhibiting NLRP3 inflammasome activation.     

Physiological concentrations of bilirubin control inflammatory response by inhibiting NF-κB and inflammasome activation

Bilirubin, as the final product of heme metabolism, has both toxic and beneficial effects on humans depending on its serum concentration. So far, whether and how physiological concentrations of bilirubin influence inflammation is largely unknown. In the current study, we established inflammatory cell models of murine peritoneal macrophages (PMs) and bone marrow-derived macrophages (BMDMs) by stimulating the cells with either lipopolysaccharide (LPS) alone or with various inflammasome stimuli. In addition, a model of mouse sepsis induced by intraperitoneal injection of LPS was also employed. We found that bilirubin, although used at physiological concentrations, could control inflammation both in vitro and in vivo. In vitro, bilirubin inhibited caspase-1 maturation and IL-1β secretion in NLRP3, AIM2, and NLRC4 inflammasomes. Besides, bilirubin inhibited the secretion of TNF-α and IL-6 in LPS-primed macrophages by reduced phosphorylation of IκB-α and p65, indicating the inhibition of the NF-κB pathway. In vivo, bilirubin significantly inhibited the release of IL-1β and TNF-α, resulting in an increased survival rate of mice with LPS-induced sepsis. Our study demonstrates a protective role of physiological concentrations of bilirubin against inflammation, the mechanisms of which involve the inhibition of the NF-κB signaling pathway as well as control of the activation of inflammasomes. Bilirubin could therefore be considered an endogenous regulatory molecule modulating inflammation. In defined doses, bilirubin could be applied as a potential medication against inflammation and inflammasome-related diseases.     

Ghrelin attenuates secondary brain injury following intracerebral hemorrhage by inhibiting NLRP3 inflammasome activation and promoting Nrf2/ARE signaling pathway in mice

Ghrelin, a brain-gut peptide, has been proven to exert neuroprotection in different kinds of neurological diseases; however, its role and the potential molecular mechanisms in secondary brain injury (SBI) after intracerebral hemorrhage (ICH) are still unknown. In this study, we investigate whether treatment with ghrelin may attenuate SBI in a murine ICH model, and if so, whether the neuroprotective effects are due to the inhibition of nucleotide-binding oligomerization domain-like receptor pyrin domain-containing 3 (NLRP3) inflammasome activation and promotion of nuclear factor-E2-related factor 2 (Nrf2)/antioxidative response element (ARE) signaling pathway. Stereotactically intrastriatal infusion of autologous blood was performed to mimic ICH. Ghrelin was given intraperitoneally immediately following ICH and again 1 h later. Results showed that ghrelin attenuated neurobehavioral deficits, brain edema, hematoma volume, and perihematomal cell death post-ICH. Ghrelin inhibited the NLRP3 inflammasome activation and subsequently suppressed the neuroinflammatory response as evidenced by reduced microglia activation, neutrophil infiltration, and pro-inflammatory mediators release after ICH. Additionally, ghrelin alleviated ICH-induced oxidative stress according to the chemiluminescence of luminol and lucigenin, malondialdehyde (MDA) content, and total superoxide dismutase (SOD) activity assays. These changes were accompanied by upregulation of Nrf2 expression, Nrf2 nuclear accumulation, and enhanced Nrf2 DNA binding activity, as well as by increased expressions of Nrf2 downstream target antioxidative genes, including NAD(P)H quinine oxidoreductase-1 (NQO1), glutathione cysteine ligase regulatory subunit (GCLC), and glutathione cysteine ligase modulatory subunit (GCLM). Together, our data suggested that ghrelin protected against ICH-induced SBI by inhibiting NLRP3 inflammasome activation and promoting Nrf2/ARE signaling pathway.