Nucleotide-binding oligomerization domain 1(NOD1) is an intracellular innate immune sensor for small molecules derived from bacterial cell components. NOD1 activation by its ligands leads to robust production of pro-i...Nucleotide-binding oligomerization domain 1(NOD1) is an intracellular innate immune sensor for small molecules derived from bacterial cell components. NOD1 activation by its ligands leads to robust production of pro-inflammatory cytokines and chemokines by innate immune cells, thereby mediating mucosal host defense systems against microbes. Chronic gastric infection due to Helicobacter pylori(H. pylori) causes various upper gastrointestinal diseases, including atrophic gastritis, peptic ulcers, and gastric cancer. It is now generally accepted that detection of H. pylori by NOD1 expressed in gastric epithelial cells plays an indispensable role in mucosal host defense systems against this organism. Recent studies have revealed the molecular mechanism by which NOD1 activation caused by H. pylori infection is involved in the development of chronic gastritis and gastric cancer. In this review, we have discussed and summarized how sensing of H. pylori by NOD1 mediates the prevention of chronic gastritis and gastric cancer.展开更多
Objective To investigate the potential role of nucleotide-binding oligomerization domain 1 (NOD1), a component of the innate immune system, in mediating lipid-induced insulin resistance in adipocytes. Methods Adipo...Objective To investigate the potential role of nucleotide-binding oligomerization domain 1 (NOD1), a component of the innate immune system, in mediating lipid-induced insulin resistance in adipocytes. Methods Adipocytes from Toll-like receptor 4 deficiency mice were used for stimulation experiments. The effect of oleate/palmitate mixture on nuclear factor-κB (NF-κB) activation was analyzed by reporter plasmid assay. The release of proinflammatory chemokine/cytokines production was determined by using real-time PCR. Insulin-stimulated glucose uptake was measured by 2-deoxy-D-[SH] glucose uptake assay. Chemokine/cytokine expression and glucose uptake in adipocytes transfected with small interfering RNA (siRNA) targeting NOD 1 upon fatty acids treatment were analyzed. Results Oleate/palmitate mixture activated the NF-κB pathway and induced interleukin-6, tumor necrosis factor-R, and monocyte chemoattractant protein-1 mRNA expressions in adipocytes from mice deficient in Toll-like receptor 4, and these effects were blocked by siRNA targeting NOD1. Furthermore, saturated fatty acids decreased the ability of insulin-stimulated glucose uptake. Importantly, siRNA targeting NOD 1 partially reversed saturated fatty acid-induced suppression of insulin-induced glucose uptake. Conclusion NOD1 might play an important role in saturated fatty acid-induced insulin resistance in adipocytes, suggesting a mechanism by which reduced NOD1 activity confers beneficial effects on insulin action.展开更多
目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、AP...目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、APE低、中、高浓度组,用1.0μg/mL的脂多糖(Lipopolysaccharide,LPS)诱导建立细胞炎症损伤模型,APE(低、中、高浓度:15、25、35μg/mL)干预后采用CCK-8法检测细胞的存活率,通过ELISA试剂盒检测炎症因子IL-1β、IL-18、TNF-α的分泌水平。蛋白质印迹法(WB)检测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)炎症小体信号通路5个关键蛋白:NLRP3、半胱氨酸天冬氨酸蛋白酶1(Cystein-asparate protease-1,Caspase-l)、凋亡相关斑点样蛋白(Apoptosis-associated speck-like protein containing a CARD,ASC)及抗凋亡蛋白Bcl-2(Anti-apoptosis Protein Bcl-2)和Bcl-xl(Anti-apoptosis Protein Bcl-xl)表达。结果与空白组比较,模型组IEC-6细胞的存活率降低,NLRP3、Caspase-1、ASC蛋白表达水平升高,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平降低,促炎因子IL-1β、IL-18和TNF-α的分泌水平升高,差异有统计学意义(P<0.05)。与模型组比较,APE低、中、高浓度组细胞存活率升高,35μg/mL APE组IEC-6细胞的NLRP3、Caspase-1、ASC蛋白相对表达水平降低,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平升高,差异有统计学意义(P<0.05)。中、高浓度的APE能够抑制炎症因子分泌,25μg/mL APE对IL-1β、IL-18、TNF-α炎症因子分泌水平抑制率分别为31.60%、31.19%和31.09%(P<0.05)。结论骆驼刺提取物通过提高抗凋亡蛋白Bcl-2、Bcl-xl的表达水平,下调NLRP3炎症小体组成成分以及促炎因子IL-1β、IL-18和TNF-α分泌,从而抑制NLRP3炎症小体组装和激活,实现缓解LPS对IEC-6细胞的损伤。展开更多
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,mo...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.展开更多
文摘Nucleotide-binding oligomerization domain 1(NOD1) is an intracellular innate immune sensor for small molecules derived from bacterial cell components. NOD1 activation by its ligands leads to robust production of pro-inflammatory cytokines and chemokines by innate immune cells, thereby mediating mucosal host defense systems against microbes. Chronic gastric infection due to Helicobacter pylori(H. pylori) causes various upper gastrointestinal diseases, including atrophic gastritis, peptic ulcers, and gastric cancer. It is now generally accepted that detection of H. pylori by NOD1 expressed in gastric epithelial cells plays an indispensable role in mucosal host defense systems against this organism. Recent studies have revealed the molecular mechanism by which NOD1 activation caused by H. pylori infection is involved in the development of chronic gastritis and gastric cancer. In this review, we have discussed and summarized how sensing of H. pylori by NOD1 mediates the prevention of chronic gastritis and gastric cancer.
基金Supported by the Grant from the Educational Department of Liaoning Province(2008810)
文摘Objective To investigate the potential role of nucleotide-binding oligomerization domain 1 (NOD1), a component of the innate immune system, in mediating lipid-induced insulin resistance in adipocytes. Methods Adipocytes from Toll-like receptor 4 deficiency mice were used for stimulation experiments. The effect of oleate/palmitate mixture on nuclear factor-κB (NF-κB) activation was analyzed by reporter plasmid assay. The release of proinflammatory chemokine/cytokines production was determined by using real-time PCR. Insulin-stimulated glucose uptake was measured by 2-deoxy-D-[SH] glucose uptake assay. Chemokine/cytokine expression and glucose uptake in adipocytes transfected with small interfering RNA (siRNA) targeting NOD 1 upon fatty acids treatment were analyzed. Results Oleate/palmitate mixture activated the NF-κB pathway and induced interleukin-6, tumor necrosis factor-R, and monocyte chemoattractant protein-1 mRNA expressions in adipocytes from mice deficient in Toll-like receptor 4, and these effects were blocked by siRNA targeting NOD1. Furthermore, saturated fatty acids decreased the ability of insulin-stimulated glucose uptake. Importantly, siRNA targeting NOD 1 partially reversed saturated fatty acid-induced suppression of insulin-induced glucose uptake. Conclusion NOD1 might play an important role in saturated fatty acid-induced insulin resistance in adipocytes, suggesting a mechanism by which reduced NOD1 activity confers beneficial effects on insulin action.
文摘目的研究骆驼刺提取物(Alhagi pseudalhagi(M.B.)Desv.Extract,APE)对脂多糖诱导的大鼠小肠隐窝上皮细胞(Intestinal epithelial cell,IEC-6)损伤模型NLRP3炎症小体及相关细胞因子的影响。方法培养IEC-6细胞,将其分为空白组、模型组、APE低、中、高浓度组,用1.0μg/mL的脂多糖(Lipopolysaccharide,LPS)诱导建立细胞炎症损伤模型,APE(低、中、高浓度:15、25、35μg/mL)干预后采用CCK-8法检测细胞的存活率,通过ELISA试剂盒检测炎症因子IL-1β、IL-18、TNF-α的分泌水平。蛋白质印迹法(WB)检测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)炎症小体信号通路5个关键蛋白:NLRP3、半胱氨酸天冬氨酸蛋白酶1(Cystein-asparate protease-1,Caspase-l)、凋亡相关斑点样蛋白(Apoptosis-associated speck-like protein containing a CARD,ASC)及抗凋亡蛋白Bcl-2(Anti-apoptosis Protein Bcl-2)和Bcl-xl(Anti-apoptosis Protein Bcl-xl)表达。结果与空白组比较,模型组IEC-6细胞的存活率降低,NLRP3、Caspase-1、ASC蛋白表达水平升高,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平降低,促炎因子IL-1β、IL-18和TNF-α的分泌水平升高,差异有统计学意义(P<0.05)。与模型组比较,APE低、中、高浓度组细胞存活率升高,35μg/mL APE组IEC-6细胞的NLRP3、Caspase-1、ASC蛋白相对表达水平降低,抗凋亡蛋白Bcl-2、Bcl-xl的表达水平升高,差异有统计学意义(P<0.05)。中、高浓度的APE能够抑制炎症因子分泌,25μg/mL APE对IL-1β、IL-18、TNF-α炎症因子分泌水平抑制率分别为31.60%、31.19%和31.09%(P<0.05)。结论骆驼刺提取物通过提高抗凋亡蛋白Bcl-2、Bcl-xl的表达水平,下调NLRP3炎症小体组成成分以及促炎因子IL-1β、IL-18和TNF-α分泌,从而抑制NLRP3炎症小体组装和激活,实现缓解LPS对IEC-6细胞的损伤。
文摘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.