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Objective To investigate the effect of BMAL1 on H2O2-induced cardiomyocyte injury through NRF2-regulated ROS/NLRP3 inflammasome pathway.Methods H9c2 cells and H9c2 cells with stable over-expressed BMAL1 were cultured and divided into the control group,the H2O2 group,the BMAL1-OE group,the BMAL1-OE+H2O2 group,the BMAL1-OE+ML385 group and the BMAL1-OE+ML385+H2O2 group.All groups were pre-intervened with corresponding inhibitors,and then treated with 0.2 mmol/L H2O2,except for the control group and the BMAL1-OE group.After the intervention,CCK-8 assay was used to measure cell viability,fluorescent probe DCFH-DA was used to measure ROS generation and Western blot assay was used to detect BMAL1,NRF2 and NLRP3 protein expressions.ELISA was used to determine IL-1β release.Results Compared with the control group,the cell viability was decreased,ROS generation was increased,BMAL1 and NRF2 protein expressions were decreased,NLRP3 expression and IL-1β release were increased in the H2O2 group(P＜0.05).Compared with the H2O2 group,the cell viability was increased,ROS generation was decreased,BMAL1-OE and NRF2 protein expressions were increased,NLRP3 expression and IL-1β release were decreased in the BMAL1-OE+H2O2 group(P＜0.05).Compared with the BMAL1-OE+H2O2 group,the cell viability was decreased,ROS generation was increased,NLRP3 expression and IL-1β release were increased in the BMAL1-OE+ML385+H2O2 group(P＜0.05).Conclusion BMAL1 attenuates H2O2-induced H9c2 cardiomyocyte injury,and its mechanism may be related to the regulation of ROS/NLRP3 inflammasome pathway through NRF2.
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Objective To investigate the impacts of phillyrin on exudates and lung injury in rats with acute pleurisy by regulating the NLRP3 inflammatory pathway.Methods Ninety rats were randomly divided into the control group,the model group,the low-dose phillyrin(PH-L,5 mg/kg)group,the medium-dose phillyrin(PH-M,10 mg/kg)group,the high-dose phillyrin(PH-H,20 mg/kg)group and the NLRP3 pathway inhibitor(PJ34,10 mg/kg)group.FVC,FEV 0.1 and FEV 0.3 were detected by lung function analyzer.Electronic balance was used to weigh the mass of chest exudate.The number of white blood cells in exudate was detected by Wright staining.Contents of prostaglandin E2(PGE2),monocyte chemoattractant protein-1(MCP-1),interleukin(IL)-6 and tumor necrosis factor-α(TNF-α)in exudate were detected by ELISA.Automatic blood gas analyzer was used to detect p(CO2)and p(O2)of rats.HE staining was used to observe pathological changes of lung tissue.The expression levels of NLRP3 and Caspase-1 protein were detected by immunohistochemistry.Western blot assay was used to detect the expression of NLRP3 pathway protein.Results Compared with the control group,the quality of pleural exudate and the number of white blood cells,the contents of PGE2,MCP-1,IL-6,TNF-α,the expression of p(CO2)and NLRP3 pathway proteins in exudate of the model group increased obviously,FVC,FEV 0.1,FEV 0.3 and p(O2)decreased obviously,and the lung tissue showed obvious pathological damage(P＜0.05).Compared with the model group,the quality of pleural exudate and the number of white blood cells,the contents of PGE2,MCP-1,IL-6,TNF-α,the expression of p(CO2),NLRP3 pathway proteins in the exudate of rats decreased obviously in the PH group and the PJ34 group,FVC,FEV 0.1,FEV 0.3 and p(O2)increased obviously,the pathological injury of lung tissue was obviously improved(P＜0.05).Compared with the PH-H group,there were no significant differences in the above indexes in the PJ34 group(P＞0.05).Conclusion PH can improve lung injury induced by acute pleurisy in rats by inhibiting the activation of NLRP3 pathway and inhibiting inflammatory reaction.
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Objective:To evaluate the role of NOD-like receptor protein 3 (NLRP3) inflammasomes in curcumin-induced reduction of sevoflurane-induced postoperative cognitive dysfunction in rats.Methods:Forty SPF healthy male Sprague-Dawley rats, aged 17-18 months, with body mass index of 580-600 g, were divided into 4 groups ( n=10 each) by a random number table method: control group (C group), postoperative cognitive dysfunction group (P group), curcumin group (CU group), and curcumin+ NLRP3 inflammasome activator group (CN group). The rat model of postoperative cognitive dysfunction was prepared by inhaling 1.5% sevoflurane to explore the abdominal cavity. Curcumin suspension 300 mg/kg was given by intragastric administration in CU group and CN group, and the rats received intragastric administration of nidrisin sodium 5 mg/kg simultaneously in CN group, once a day for 6 consecutive days. Rats received the equal volume of normal saline instead in C group and P group. The frequency of crossing the original platform and time spent in the target quadrant were measured by the Morris water maze test. The histopathological changes of hippocampus were observed by HE staining, neuronal apoptosis was detected by TUNEL staining, and the expression of NLRP3, Bcl-2 and Bax was detected by Western blot. Results:Compared with C group, the frequency of crossing the original platform was significantly reduced, the time spent in the target quadrant was shortened, the apoptosis rate of neurons was increased, and the expression of NLRP3 and Bax was up-regulated, and the expression of Bcl-2 was down-regulated in P group ( P<0.05). Compared with P group, the frequency of crossing the original platform was significantly increased, the time spent in the target quadrant was prolonged, the apoptosis rate of neurons was decreased, and the expression of NLRP3 and Bax was down-regulated, and the expression of Bcl-2 was up-regulated in CU group ( P<0.05). Compared with CU group, the frequency of crossing the original platform was significantly reduced, the time spent in the target quadrant was shortened, the apoptosis rate of neurons was increased, and the expression of NLRP3 and Bax was up-regulated, and the expression of Bcl-2 was down-regulated in CN group ( P<0.05). Conclusions:The NLRP3 inflammasome is involved in curcumin-induced reduction of postoperative cognitive dysfunction in sevoflurane-anesthetized rats.
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Objective:To investigate the efficacy and mechanism of canagliflozin (Cana) in the treatment of high glucose-induced human podocyte (HPC) injury.Methods:The HPCs were divided into 5 groups: normal glucose group (NG group), mannitol group (MA group), high glucose group (HG group), Cana low dose (0.3 μmol/L) group and Cana high dose (1.0 μmol/L) group. Western blotting was used to examine the protein expressions of membrane-associated guanylate kinase inverted-2 (MAGI2), podocyte-associated protein nephrin, sodium-glucose transporter 2 (SGLT2), NOD-like receptor thermal protein domain associated protein 3 (NLRP3), apoptosis- associated speck-like protein containing a CARD (ASC), and cleaved-caspase1 in podocytes. Phalloidin staining of F-actin in podocytes was used to observe cytoskeletal injury. Intracellular reactive oxygen species (ROS) level of HPC was detected by the 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) probe. Levels of interleukin (IL)-18 and IL-1β in culture medium of podocytes were detected by enzyme-linked immunosorbent assay (ELISA).Results:(1) Compared with the NG group, the protein expressions of MAGI2 and nephrin decreased (both P<0.01), the protein expression of SGLT2 increased ( P<0.01), the changes of cell morphology and cytoskeleton remodeling were obvious, intracellular ROS level increased ( P<0.01), while NLRP3, ASC and cleaved-caspase1 protein expressions decreased in the HG group (all P<0.01). The results of ELISA showed that IL-18 and IL-1β concentrations were higher in the HG group (both P<0.05). (2) Compared with the HG group, in the Cana groups, MAGI2 and nephrin expressions up-regulated (both P<0.01), the changes of cell morphology and cytoskeleton remodeling were alleviated. Meanwhile the Cana groups showed decreased SGLT2 expression ( P<0.05), lower ROS level, down- regulated NLRP3, ASC, cleaved-caspase1 expressions (all P<0.01), and decreased concentrations of IL-18 and IL-1β in culture medium of podocytes (both P<0.05). Conclusion:Cana can improve high glucose-induced injury and inflammation in human podocyte, possibly due to the repression of the ROS/NLRP3 signaling pathway.
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ObjectiveTo investigate the effect of NOD-like receptor family pyrin domain containing 3 （NLRP3） knockdown on a mouse model of nonalcoholic steatohepatitis （NASH） induced by high-fat high-carbohydrate （HFHC） diet. MethodsA total of 44 mice were randomly divided into normal diet group （CON group） with 20 mice and HFHC group with 24 mice. At the end of week 14 of modeling， 4 mice were randomly selected from the HFHC group for the pre-experiment of adeno-associated virus （AAV） by tail vein injection， and NLRP3 knockdown was verified after 4 weeks. After NLRP3 knockdown was verified at the end of week 18， the remaining 40 mice were given a single tail vein injection of AAV， and then they were divided into CON+NLRP3 knockdown negative control group （CON+NLRP3-NC group）， CON+NLRP3 knockdown group （CON+NLRP3-KD group）， HFHC+NLRP3-NC group， and HFHC+NLRP3-KD group， with 10 mice in each group. At the end of week 24， the activation of NLRP3 inflammasome was observed； related indicators were measured， including body weight， liver weight， liver index， and glucose metabolism （fasting blood glucose， fasting insulin， and Homeostasis Model Assessment of Insulin Resistance ［HOMA-IR］ index）； the indicators of liver lipid content （liver triglyceride ［TG］ and oil red O staining）， liver inflammation （serum alanine aminotransferase ［ALT］ activity， HE staining， and inflammation-related genes）， and liver fibrosis （Sirius Red staining and fibrosis-related genes） were measured. A one-way analysis of variance was used for comparison of continuous data between multiple groups， and the least significant difference t-test was used for further comparison between two groups. ResultsCompared with the CON+NLRP3-NC group based on the results of Western Blot， the HFHC+NLRP3-NC group had significant increases in the protein expression levels of NLRP3， pro-Caspase1， Caspase1， ASC， and IL-1β， while the HFHC+NLRP3-KD group had significant reductions in these levels （all P<0.05）. The HFHC+NLRP3-NC group showed varying degrees of increase in body weight， liver weight， liver index， and glucose metabolism indicators， while the HFHC+NLRP3-KD group showed significant improvements in these indicators （all P<0.05）. As for hepatic fat deposition， compared with the CON+NLRP3-NC group， the HFHC+NLRP3-NC group had a significant increase in liver TG， with a large number of red lipid droplets shown by oil red O staining， and the HFHC+NLRP3-KD group had significant reductions in liver TG and the number of lipid droplets in the liver （all P<0.01）. In terms of liver inflammation， compared with the CON+NLRP3-NC group， the HFHC+NLRP3-NC group had significant increases in serum ALT， NAFLD activity score， and inflammation-related genes， while the HFHC+NLRP3-KD group had significant reductions in these indicators （all P<0.01）. As for liver fibrosis， compared with the CON+NLRP3-NC group， the HFHC+NLRP3-NC group had significant increases in collagen fiber area and fibrosis-related genes， and the HFHC+NLRP3-KD group had significant reductions in fibrosis-related genes （all P<0.05） and a tendency of reduction in collagen fiber area （P>0.05）. ConclusionNLRP3 knockdown can significantly improve hepatic fat deposition and inflammation in a mouse model of HFHC-induced NASH.
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In recent years， NOD-like receptor protein 3 （NLRP3） inflammasome in tumors has become a research hotspot， especially in melanoma， colorectal cancer， lung cancer， and breast cancer， and more and more evidence has shown that inflammation plays a role in the development， progression， angiogenesis， and invasion of cancer. Hepatocellular carcinoma （HCC） is the most common type of primary liver cancer， and there are still controversies over the role of NLRP3 inflammasome in the development and progression of HCC. Therefore， this article reviews the potential impact of NLRP3 inflammasome in the progression of HCC and its mechanism of action in anticancer therapy， and it is believed that NLRP3 inflammasome can be used as an effective therapeutic target for HCC patients.
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Objective:Four cases with NLRP3-related autoinflammatory diseases were reported to summarize the clinical characteristics, genotype, and treatment responses of the disease, and to improve clinical pediatricians' understanding of the disease.Methods:A retrospective analysis was performed on 4 cases with NLRP3-related autoinflammatory diseases diagnosed in Children's Hospital of Anhui Province in 2016—2021, and the clinical features and treatment progress of NLRP3-related autoinflammatory diseases were retrospectively analyzed based on the clinical features, gene reports, and literature review.Results:① All 4 cases were male. Cases 1, 2, and 3 had the disease onset after birth, and case 4 had the disease onset 6 months after birth. All showed periodic fever, repeated urticaria-like rash, protruding forehead, and saddle nose. White blood cells count, erythrocyte sedimentation rate, and C-reactive protein were increased during the attack period, and those in the interval period were normal, and antibiotic treatment was ineffective. ② The genetic test of all these 4 children showed NLRP3 mutation. Children 1, 2, and 3 were heterozygous mutations, and their parents were wild-type. The mutation was located at chromosome Chr1: 247587658, exon c913 (exon3). G>A, the 305th aspartic acid (Asp) of the protein was changed to asparagine (Asn) in child 1. The mutation was located at the chromosomal Chr1: 247588072, the nucleic acid was changed to c1327(exon3)T>C, and the amino acid was changed to p.Y443H in cases 2 and 3. Somatic heterozygous mutation was found in case 4, and the child's parents were wild-type. In this case, the mutation was located at chromosomal Chr1: 247587658, exon3 G>A, and the 305th Asp of the protein was changed to Asn. ③Children in cases 1, 2, and 3 were treated with glucocorticoids and non-steroidal anti-inflammatory drugs at the initial stage, but the effects were limited. After receiving IL-1 antagonist treatment fever, skin rash, joint swelling and pain disappeared, and the inflammatory indexes were returned to normal. The child 4 received non-steroidal anti-inflammatory drugs and methotrexate, but he failed to respond to the treatment. Treatment with tocilizumab was not effective, however, fever, skin rash, or joint pain disappeared after treated with Khanna.Conclusion:①NLRP3-related autoinflammatory diseases can cause periodic fever, urticaria, joint involvement, and severe involvement of the central nervous system and organ amyloidosis. Which are early misdiagnosis is prone to systemic juvenile idiopathic arthritis. ②The disease was an inflammatory disease mediated by interleukin-1. At present, non-steroidal anti-inflammatory drug, glucocorticoid and chronic anti-rheumatic drugs have limited effects. IL-1 antagonists are effective and safe in the treatment of the disease.
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Objective:To evaluate the role of nuclear factor erythroid 2-related factor 2 (Nrf2)/nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) signaling pathway in propofol postconditioning-induced reduction of hippocampal neuron injury in a rat model of oxygen-glucose deprivation and restoration (OGD/R).Methods:The hippocampal neurons were isolated from fetal rats of Wistar rats at 16-18 days of gestation and primarily cultured for 7 days and then divided into 4 groups ( n=42 each) using a random number table method: control group (group C), OGD/R group (group O), propofol post-conditioning group (group P) and Nrf2 siRNA(-) transfection group (group N). The cells were routinely cultured in group C. The cells were subjected to oxygen-glucose deprivation for 1 h followed by oxygen and glucose supply in group O. Propofol (final concentration 1.2 μg/ml) was added immediately after oxygen and glucose supply, the cells were then cultured for 2 h, and the culture medium was replaced with the normal culture medium in group P. The primarily cultured neurons were transfected with Nrf2 gene knockout lentivirus on 3rd day of culture, 24 h later the cells were then routinely cultured, and the model was prepared and propofol conditioning was performed on 7th day. Cells were collected at 24 h of incubation for determination of the cell apoptosis (by flow cytometry), expression of Nrf2 and NLRP3 mRNA and protein (using quantitative real-time polymerase chain reaction or Western blot), concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1β, and activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) (kit method). Results:Compared with group C, the apoptosis rate of neurons was significantly increased, concentrations of TNF-α, IL-6 and IL-1β were increased, the levels of GSH, SOD and CAT were decreased, the expression of Nrf2 and NLRP3 protein and mRNA was up-regulated, and the nuclear/plasma ratio of Nrf2 was increased in O and P groups ( P<0.05). Compared with group O, the apoptosis rate of neurons was significantly decreased, the concentrations of TNF-α, IL-6 and IL-1 β were decreased, the levels of GSH, SOD and CAT were increased, the expression of Nrf2 protein and mRNA was up-regulated, the nuclear/plasma ratio of Nrf2 was increased, and the expression of NLRP3 protein and mRNA was down-regulated in group P ( P<0.05). Compared with group P, the apoptosis rate of neurons was significantly increased, concentrations of TNF-α, IL-6 and IL-1β were increased, the levels of GSH, SOD and CAT were decreased, the expression of Nrf2 protein and mRNA was down-regulated, the nuclear/plasma ratio of Nrf2 was decreased, and the expression of NLRP3 protein and mRNA was up-regulated in group N ( P<0.05). Conclusions:Nrf2/NLRP3 signaling pathway is involved in propofol postconditioning-induced reduction of hippocampal neuron injury in a rat model of OGD/R.
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Objective:To evaluate the role of astrocytic NOD-like receptor protein 3 (NLRP3) in the lateral hypothalamus (LHA) in anxiety-like behaviors after hemorrhagic shock and resuscitation in mice.Methods:Forty-eight clean-grade male C57BL/6 mice, aged 10 weeks, weighing 25-30 g, were divided into 4 groups ( n=12 each) using a random number table method: sham operation group (group C), hemorrhagic shock and resuscitation group (group H), hemorrhagic shock and resuscitation + adeno-associated virus group (group HI), and hemorrhagic shock and resuscitation + control virus group (group HIV). The model of hemorrhagic shock and resuscitation was developed by bleeding and re-transfusion through the femoral vein in H, HI and HIV groups. At 21 days before developing the model, AAV-GfaABC1D-EGFP-Cre was injected into bilateral LHA in group HI, and AAV-GfaABC1D-EGFP was administered as a control in group HIV. Anxiety-like behaviors were evaluated by EPM-maze and bead-burying tests at 14 days after resuscitation. Mice were immediately sacrificed at the end of behavioral tests, and LHA-containing brain tissues were obtained for determination of co-localization of NLRP3 with glial fibrillary acidic protein (GFAP), the fluorescence intensity of Wisteria floribunda agglutinin was measured using immunofluorescent staining to reflect the expression of extracellular matrix in the LHA, and the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells in total cells was calculated. Results:Compared with group C, the number of buried beads and percentage of time of staying at the open arm were significantly decreased, the expression of extracellular matrix in the LHA was down-regulated, and the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells was increased in H, HI and HIV groups, and the co-localization coefficient of NLRP3 and GFAP was significantly decreased in group HI ( P<0.01). Compared with group H, the number of buried particles and percentage of time of staying at the open arm were significantly decreased, the expression of extracellular matrix in the LHA was up-regulated, the co-location coefficient of NLRP3 and GFAP was decreased, the percentage of cleaved caspase-1/GFAP and IL-18/GFAP positive cells was decreased ( P<0.01), and no significant change was found in the parameters mentioned above in group HIV ( P>0.05). Conclusions:Anxiety-like behaviors after hemorrhagic shock and resuscitation is associated with astrocytic NLRP3-induced pyroptosis in the LHA and reduction of extracellular matrix in mice.
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Objective:To evaluate the effect of verbascoside on cold ischemia-reperfusion injury following heterotopic heart transplantation in mice and the relationship with nuclear factor kappa B (NF-κB)/nucleotide-binding oligomerization domain-like receptor containing pyrin domain 3 (NLRP3) signaling pathway.Methods:This experiment was performed in two parts. Part Ⅰ animal experiment Eighteen SPF healthy male C57BL/6 mice, aged 6-8 weeks, weighing 24-28 g, were divided into 3 groups ( n=6 each) by the random number table method: control group (C group), cold ischemia-reperfusion (I/R) group (I/R group) and cold I/R + verbascoside group (I/R+ VB group). Cold I/R injury model of mouse heart transplantation was prepared by neck heterotopic heart transplantation using the modified non-suture cuff technique. The donor heart in group C was immediately transplanted to the recipient after removal, while the donor heart in group I/R was stored in the 4 ℃ University of Wisconsin solution for 8 h before transplantation to the recipient, and verbascoside 20 mg/kg was intraperitoneally injected at 3 days before surgery in donor and recipient mice in I/R+ VB group. At the end of reperfusion, the myocardial tissue of the transplanted heart was obtained after assessing the beating score for determination of malondialdehyde (MDA) content and superoxide dismutase (SOD) activity by enzyme-linked immunosorbent assay. Part of the donor myocardium was taken for examination of the pathological results. The expression of NF-κB, p-NF-κB, NOD-like receptor protein 3 (NLRP3), ACS and caspase-1 was detected by Western blot. The expression of IL-1β, TNF-α and IL-6 mRNA was detected by real-time polymerase chain reaction. Part Ⅱ cell experiment Rat cardiomyocyte H9c2 cold hypoxia-reoxygenation model was developed, and the cells were divided into 3 groups ( n=24 each) by the random number table method: control group (C group), cold hypoxia-reoxygenation group (H/R group), and cold hypoxia-reoxygenation+ verbascoside group (H/R+ VB group). The cells were exposed to hypoxia for 18 h at 10 ℃ followed by restoration of reoxygenation for 24 h at 37 ℃ to develop the cold hypoxia-reoxygenation model. The cell viability and LDH activity were determined. The expression of NF-κB and NLRP3 was detected by Western blot, and the expression of phosphorylated NF-κB (p-NF-κB) was detected by immunofluorescence staining. Results:Part Ⅰanimal experiment Compared with C group, the MDA content was significantly increased, the beating score of grafts and SOD activity were decreased, and the expression of p-NF-κB, NLRP3, ACS and caspase-1 and IL-1β, TNF-α and IL-6 mRNA was up-regulated ( P<0.05), and myocardial histopathological injury was aggravated in I/R group. Compared with I/R group, the content of MDA was significantly decreased, the beating score of grafts and SOD activity were increased, the expression of p-NF-κB, NLRP3, ACS and caspase-1 and IL-1β, TNF-α and IL-6 mRNA was down-regulated ( P<0.05), and the myocardial histopathological injury was alleviated in I/R+ VB group. Part Ⅱ cell experiment Compared with C group, the cell viability was significantly decreased, the activity of LDH was increased, and the expression of p-NF-κB, NLRP3, ACS, caspase-1 and p-NF-κB was up-regulated in H/R group ( P<0.05). Compared with H/R group, the cell viability was significantly increased, the activity of LDH was decreased, and the expression of p-NF-κB, NLRP3, ACS, caspase-1 and p-NF-κB was down-regulated in H/R+ VB group ( P<0.05). Conclusions:Verbascoside can alleviate cold I/R injury following heterotopic heart transplantation in mice, and the mechanism may be related to inhibition of activation of NF-κB/NLRP3 signaling pathway.
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Objective:To evaluate the role of inositol-requiring kinase 1α-X-box binding protein 1 (IRE1α/XBP1) signaling pathway in endoplasmic reticulumin in endotoxin-induced acute lung injury (ALI) in mice and the relationship with NOD-like receptor pyrin domain containing 3 (NLRP3) inflammasomes.Methods:Thirty-six SPF-grade healthy male C57BL/6 mice, aged 6-8 weeks, weighing 25-30 g, were divided into 3 groups ( n=12 each) according to the random number table method: control group (group C), endotoxin-induced ALI group (group ALI) and endotoxin-induced ALI+ STF-083010 group (group ST). The ALI model was established by inhaling nebulized lipopolysaccharide (LPS) 3 mg/ml for 30 min in ALI and ST groups, while the equal volume of nebulized normal saline was given in group C. IRE1α/XBP1 signaling pathway inhibitor STF-083010 50 mg/kg was intraperitoneally injected at 1 h before inhaling LPS in group ST, while the remaining two groups received the equal volume of normal saline intraperitoneally. Mice were sacrificed at 24 h after inhaling nebulized LPS or normal saline, bronchoalveolar lavage fluid (BALF) were collected and lung tissues were removed for microscopic examination of the pathological changes (by HE staining) which were scored and for determination of wet/dry lung weight ratio (W/D ratio), concentrations of interleukin-1beta (IL-lβ) and IL-18 in BALF (by enzyme-linked immunosorbent assay) and expression of phosphorylated IRE1α (p-IRE1α), XBP1s, NLRP3, ASC and caspase-1 in lung tissues (by Western blot). Results:Compared with group C, the W/D ratio, lung injury score and concentrations of IL-1β and IL-18 in BALF were significantly increased, and the expression of p-IRE1α, XBP1s, NLRP3, ASC and caspase-1 in lung tissues was up-regulated in group ALI and group ST ( P<0.001). Compared with group ALI, the W/D ratio, lung injury score and concentrations of IL-1β and IL-18 in BALF were significantly decreased, and the expression of p-IRE1α, XBP1s, NLRP3, ASC and caspase-1 protein in lung tissues was down-regulated in group ST ( P<0.001). Conclusions:IRE1α/XBP1 signaling pathway is involved in LPS-induced ALI in mice, and the mechanism is related to activation of NLRP3 inflammasomes.
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Objective:To evaluate the relationship between Sestrin2 and mitochondrial DNA (mtDNA)-NOD-like receptor associated protein 3 (NLRP3) inflammasome pathway during endotoxin-induced myocardial injury in mice.Methods:One hundred and eighty-four clean-grade healthy male ICR mice, aged 8-12 weeks, weighing 20-25 g, were used in this study. One hundred and sixty-eight mice were divided into 7 groups ( n=24 each) using the random number table method: normal control group (N group), lipopolysaccaride(LPS) group (L group), mtDNA group, LPS+ mtDNA group (M group), normal control+ negative control adeno-associated virus (AAV-NC)group (NC group), LPS+ mtDNA+ AAV-NC group (MC group), and LPS+ mtDNA+ Sestrin2 overexpression adeno-associated virus (AAV-Sestrin2) group (MSgroup). Another 10 mice were used to detect the transfection effect of AAV-Sestrin2, and the left 6 mice were used for mtDNA extraction. The model of endotoxemia was developed by intraperitoneal injection of LPS 10 mg/kg. mtDNA 5 mg/kg was intraperitoneally injected in mtDNA group, and mtDNA 5 mg/kg was intraperitoneally injected at 30 min after LPS injection in M group.AAV-Sestrin2 150 μl was injected via the tail vein in MS group, and the equal volume of AAV-NC was injected via the tail vein in MC and NC groups. Four weeks after virus injection, LPS 10 mg/kg was intraperitoneally injected and 30 min later mtDNA 5 mg/kg was intraperitoneally injected in MS and MC groups. Blood samples were collected at 24 h after LPS injection for determination of serum creatine kinase-MB (CK-MB) and lactate dehydrogenase (LDH) activities (by biochemical assay), concentrations of serum cardiac troponin I (cTnI), interleukin-18 (IL-18) and interleukin-1beta (IL-1β)(by enzyme-linked immunesorbent assay), and expression of mtDNA (by quantitative real-time polymerase chain reaction). The animals were sacrificed after the end of blood sampling and myocardial tissues were obtained for determination of the contents of reactive oxygen species (ROS), total antioxidant capacity (T-AOC), and adenosine triphosphate (ATP) and expression of NOD-like receptor associated protein 3 (NLRP3), active subunit p20 of caspase-1 (caspase-1p20) and apoptosis-associated microprotein (ASC) in myocardial tissues (by Western blot) and for microscopic examination of the pathological changes after HE staining (with a light microscope). Results:Compared with N group, the levels of CK-MB, LDH, cTnI, IL-1β and IL-18 in serum were significantly increased, the expression of mtDNA was up-regulated, the ROS content in myocardial tissues was increased, the T-AOC and ATP contents in myocardial tissues were decreased, the expression of NLRP3, caspase-1p20 and ASC in the myocardial tissues was up-regulated( P<0.05), and the pathological changes of myocardial tissues were aggravated in L group and mtDNA group.Compared with L group and mtDNA group, the levels of CK-MB, LDH, cTnI, IL-1β and IL-18 in serum were significantly increased, the expression of mtDNA was up-regulated, the ROS content in myocardial tissues was increased, the T-AOC and ATP contents in myocardial tissues were decreased, the expression of NLRP3, caspase-1p20 and ASC in the myocardial tissues was up-regulated( P<0.05), and the pathological changes of myocardial tissues were aggravated in M group. Compared with M group, the levels of CK-MB, LDH, cTnI, IL-1β and IL-18 in serum were significantly decreased, the expression of mtDNA was down-regulated, the ROS content in myocardial tissues was decreased, the T-AOC and ATP contents in myocardial tissues were increased, the expression of NLRP3, caspase-1p20 and ASC in the myocardial tissues was down-regulated( P<0.05), and the pathological changes of myocardial tissues were significantly attenuated in MS group. Conclusions:Sestrin2 can reduce endotoxin-induced myocardial injury in mice by alleviating mitochondrial damage, inhibiting oxidative stress, protecting mtDNA from oxidative damage, and then inhibiting mtDNA-NLRP3 inflammasome pathway.
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Objective:To evaluate the relationship between cannabinoid receptor 1 (CB1R) and the NOD-like receptor thermal protein domain-associated protein 3 (NLRP3) during the reduction of cerebral ischemia-reperfusion (I/R) injury by electroacupuncture (EA) preconditioning in rats.Methods:Forty SPF healthy male Sprague-Dawley rats, aged 7-9 weeks, weighing 250-280 g, were divided into 5 groups ( n=8 each) according to the random number table method: sham operation group (Sham group), cerebral I/R group (I/R group), EA preconditioning group (EA group), CB1R antagonist AM251+ EA preconditioning group (AM251+ EA group), and CB1R agonist WIN 55, 212-2 group (WIN group). Cerebral I/R was induced by middle cerebral artery occlusion (MCAO) in anesthetized animals. In EA group, EA preconditioning was performed, and the acupoint Baihui (GV20) was stimulated for 30 min with disperse-dense waves, the intensity of 1 mA and frequency of 2/15 Hz once a day for 5 consecutive days, and the model of cerebral I/R injury was developed at 24 h after the last EA. In AM251+ EA group, CB1R antagonist AM251 1 mg/kg was intraperitoneally injected at 30 min before each stimulation, and the remaining operations were the same as those previously described in EA group. CB1R agonist WIN 55, 212-2 1.5 mg/kg was intraperitoneally injected for 5 consecutive days, and the model of cerebral I/R injury was prepared at 24 h after the last injection in WIN group. Neurological behavior was assessed and scored at 3 days of reperfusion. Then the rats were sacrificed, and brains were removed, and the infarct volume was measured by TTC staining, and the tissues in the ischemic penumbra were extracted for determination of the expression of NLRP3, caspase-1 and interleukin-1bata (IL-1β) by Western blot. Results:Compared with Sham group, the percentage of cerebral infarct volume was significantly increased, the neurobehavioral score was decreased, and the expression of NLRP3, caspase-1 and IL-1β was up-regulated in I/R group ( P<0.05). Compared with I/R group, the percentage of cerebral infarct volume was significantly decreased, the neurobehavioral score was increased, and the expression of NLRP3, caspase-1 and IL-1β was down-regulated in EA and WIN groups ( P<0.05). Compared with EA group, the percentage of cerebral infarct volume was significantly increased, the neurobehavioral score was decreased, and the expression of NLRP3, caspase-1 and IL-1β was up-regulated in AM251+ EA group ( P<0.05). Conclusions:EA preconditioning may inhibit the activation of NLRP3 inflammasomes by activating CB1R, thus alleviating cerebral I/R injury in rats.
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Objective:To evaluate the role of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) in sepsis-associated encephalopathy (SAE) and the relationship with pyroptosis in microglia of mice.Methods:Twenty-four SPF healthy male C57BL/6J mice, aged 6-8 weeks, weighing 18-22 g, were divided into 3 groups ( n=6 each) using a random number table method: sham operation group (Sham group), SAE group and SAE plus an NLRP3 inhibitor MCC950 group (SAE+ MCC950 group). The mouse model of SAE was prepared by cecal ligation and puncture after anesthesia. MCC950 20 mg/kg was intraperitoneally injected at 1 h after developing the model in SAE+ MCC950 group, and the equal volume of normal saline was given instead in the other groups. Open field tests were conducted at 1 day after developing the model to record the number of rearing and time spent in the central area. Novel object recognition tests were conducted at 2-3 days after developing the model to record the recognition index. After the behavioral experiment on 3 day after developing the model, mice were sacrificed and hippocampal tissues were collected for determination of the expression of NLRP3 (by Western blot), count of cells co-expressing NLRP3 and microglia-specific ionized calcium-binding adaptor molecule 1 (Iba-1) (by immunofluorescence), activity of caspase-1, and contents of interleukin-1beta(IL-1β) and IL-18 (by enzyme-linked immunosorbent assay). Results:Compared with Sham group, the number of rearing was significantly reduced, the time spent in the central area was shortened, the recognition index was decreased, the expression of NLRP3 was up-regulated, the count of NLRP3 + -Iba-1 + cells was increased, and the activity of caspase-1 and contents of IL-1β and IL-18 were increased in SAE and SAE+ MCC950 groups ( P<0.05). Compared with SAE group, the number of rearing was significantly increased, the time spent in the central area was prolonged, the recognition index was increased, the expression of NLRP3 was down-regulated, the count of NLRP3 + -Iba-1 + cells was decreased, and the activity of caspase-1 and contents of IL-1β and IL-18 were decreased in SAE+ MCC950 group ( P<0.05). Conclusions:NLRP3 is involved in the development of SAE, which may be related to the mediation in microglial pyroptosis in mice.
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Objective:To evaluate the role of bilateral superior cervical sympathetic ganglia (SCG) in myocardial ischemia-reperfusion (I/R) injury in mice and the relationship with NOD-like receptor protein 3 (NLRP3) inflammasomes.Methods:Thirty-two healthy SPF male C57BL mice, aged 8-10 weeks, weighing 25-30 g, were divided into 4 groups ( n=8 each) by the random number table method: sham operation group (NS group), myocardial I/R group (NIR group), bilateral SCG excision group (SCGx group) and bilateral SCG excision + myocardial I/R group (SCGx+ IR group). The myocardial I/R injury model was prepared by ligating the anterior descending branch of the left coronary artery for 30 min followed by 24 h reperfusion in isoflurane-anesthetized mice. Bilateral superior cervical sympathectomy was performed at 3 days before reperfusion. Blood samples were collected from the inferior vena cava at 24 h of reperfusion for examination of pathological changes (by HE and WGA staining) and for measurement of serum creatine kinase isoenzymes (CK-MB) activity, cardiac troponin I (cTnI) concentration, norepinephrine (NE) concentration and lactic dehydrogenase (LDH) activity (by enzyme-linked immunosorbent assay), superoxide dismutase (SOD) activity (by colorimetric method), myocardial reactive oxygen species (ROS) level (by DHE method), myocardial infarct size(by TTC method), and expression of interleukin-1beta (IL-1β), IL-6, IL-10, tumor necrosis factor-alpha (TNF-α), NLRP3 mRNA (by quantitativepolymerase chain reaction ), and expression of tyrosine hydroxylase (TH), IL-1β, TNF-α, NLRP3, atrial natriuretic peptide (ANP)and brain natriuretic peptide (BNP) (by Western blot). Results:Compared with NS group, the NE concentration was significantly decreased, and TH expression was down-regulated in SCGx group, and the serum CK-MB activity, concentrations of cTnI and NE, LDH activity and myocardial ROS level were significantly increased, SOD activity was decreased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was up-regulated, and the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was up-regulated in NIR group ( P<0.05). Compared with SCGx group, the serum CK-MB activity, concentrations of cTnI and NE, LDH activity and myocardial ROS levels were significamtly increased, SOD activity was decreased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was up-regulated, and the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was up-regulated in SCGx+ NIR group ( P<0.05). Compared with NIR group, the serum CK-MB activity, cTnI concentration, LDH activity and myocardial ROS level were significantly decreased, SOD activity was increased, the expression of IL-1β, TNF-α, NLRP3, ANP and BNP was down-regulated, the expression of IL-1β, IL-6, TNF-α and NLPR3 mRNA was down-regulated, and myocardial infarct size was decreased in SCGx+ NIR group ( P<0.05). Conclusions:The mechanism by which bilateral SCG excision attenuates myocardial I/R injury is associated with decreased NLRP3 inflammatory inflammasome activation and inhibition of inflammatory responses in mice.
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Objective:To evaluate the role of silent information regulator-1 (SIRT1)/nucleotide-binding domain (NOD)-like receptor protein-3 (NLRP3) signaling pathway in sevoflurane postconditioning-induced attenuation of oxygen-glucose deprivation and restoration (OGD/R) injury in mouse hippocampal neuronal cell line (HT22) cells.Methods:The HT22 cells were seeded in a culture plate (96-well plate, 100 μl/well; 6-well plate, 2 ml/well) at the density of 5×10 4 cells/ml or in a culture dish (6 cm in diameter) and then divided into 4 groups ( n=24 each) using a random number table method: control group (Control group), OGD/R group, sevoflurane postconditioning group (SPC group), and SIRT1 small interfering RNA group (si-SIRT 1 group). In Control group, cells were cultured at 37 ℃ in normal culture atmosphere. In OGD/R group, the culture medium was replaced with glucose-free serum-free culture medium, and cells were exposed to 95% N 2+ 5% CO 2 for 4 h in an incubator at 37 ℃, and then the glucose-free serum-free culture medium was replaced with the primary culture medium, and cells were cultured for 24 h at 37 ℃ in normal culture atmosphere. In SPC group, the glucose-free serum-free culture medium was replaced with the primary cell culture medium after 4-h oxygen and glucose deprivation, the cells were put into the hypoxia incubator chamber which was filled with 2% sevoflurane immediately after start of reoxygenation, then the chamber was placed in an incubator and the cells were cultured for 1 h at 37 ℃ in normal culture atmosphere, and finally the cells were removed from the chamber and cultured for 23 h at 37 ℃ in normal culture atmosphere. In si-SIRT1 group, SIRT1 small interfering RNA 150 pmol was added at 24 h before surgery, cells were then incubated, and the other procedures were the same as those previously described in group SPC. The cell survival rate was determined using MTT assay. TUNEL assay was used to detect cell apoptosis, and the apoptosis rate was calculated. The expression of SIRT1, NLRP3, IL-1β and IL-18 mRNA was determined using polymerase chain reaction. The expression of SIRT1, NLRP3, interleukin-1beta (IL-1β) and IL-18 was detected using Western blot. Results:Compared with Control group, the cell survival rate was significantly decreased, the apoptosis rate was increased, the expression of SIRT1 protein and mRNA was down-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was up-regulated in OGD/R group ( P<0.05). Compared with OGD/R group, the cell survival rate was significantly increased, the apoptosis rate was decreased, the expression of SIRT1 protein and mRNA was up-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was down-regulated in SPC group ( P<0.05). Compared with SPC group, the cell survival rate was significantly decreased, the apoptosis rate was increased, the expression of SIRT1 protein and mRNA was down-regulated, and the expression of NLRP3, IL-1β and IL-18 protein and mRNA was up-regulated in si-SIRT1 group ( P<0.05). Conclusions:Activation of SIRT1-NLRP3 signaling pathway is involved in sevoflurane postconditioning-induced attenuation of OGD/R injury in HT22 cells.
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Objective:To investigate the potential function and related mechanism of microRNA-223 (miRNA-223) in the podocyte pyroptosis of hepatitis B virus (HBV)-associated glomerulonephritis induced by HBV X protein (HBx).Methods:HBx-overexpressing lentivirus was transfected into human renal podocytes to mimic the pathogenesis of HBV-GN. Real-time fluorescence quantitative PCR and Western blotting experiments were used to detect the mRNA and protein expression of pyroptosis-related proteins [nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3), apoptosis-associated speck-like protein containing a CARD (ASC) and caspase-1], and inflammatory factors (interleukin-1β and interleukin-18), respectively.TUNEL staining and flow cytometry were used to detect the number of pyroptosis cells. Immunofluorescence staining was used to detect the expression of podocytes biomarkers desmin and nephrin; Hoechst 33342 staining was used to observe the morphological and quantitative changes of podocyte nuclei. Enzyme-linked immunosorbent assay was used to measure caspase-1 activity. The dual luciferase reporter gene assay was used to verify the downstream target of miRNA-223. Podocytes were divided into the following nine groups: control group (no special treatment), empty plasmid group (transfected with empty plasmid), HBx overexpression group (transfected with HBx overexpression lentivirus), HBx overexpression+miRNA-223 mimic group (transfected with HBx overexpression lentivirus and miRNA-223 mimic), HBx overexpression+miRNA-223 inhibitor group (transfected with HBx overexpression lentivirus and miRNA-223 inhibitor), HBx overexpression+miRNA-223 mimic+NLRP3 group (transfected with HBx overexpression lentivirus, miRNA-223 mimic and NLRP3 overexpression plasmid), HBx overexpression+miRNA-223 mimic+ NLRP3 siRNA group (transfected with HBx overexpression lentivirus, miRNA-223 mimic and NLRP3 siRNA), HBx overexpression+miRNA-223 inhibitor+NLRP3 group (transfected with HBx overexpression lentivirus, miRNA-223 inhibitor and NLRP3 overexpression plasmid), HBx overexpression+miRNA-223 inhibitor+NLRP3 siRNA group (transfected with HBx overexpression lentivirus, miRNA-223 inhibitor and NLRP3 siRNA).Results:miRNA-223 was down-regulated in HBx overexpression group compared with the control group ( P < 0.05). TUNEL and immunofluorescence staining showed that NLRP3 knockdown attenuated podocyte injury and pyroptosis induced by HBx overexpression ( P < 0.05). Dual luciferase reporter gene assay demonstrated that NLRP3 was one of the downstream targets of miRNA-223. Rescue experiments revealed that NLRP3 overexpression weakened the protective effect of miRNA-223 in podocyte injury ( P < 0.05). The addition of miRNA-223 mimic and NLRP3 siRNA decreased the expression of NLRP3 inflammasome and cytokines, and reduced the number of pyroptosis cells induced by HBx overexpression (all P < 0.05); The addition of miRNA-223 inhibitor and NLRP3 overexpression plasmid significantly increased the expression of NLRP3 inflammasome and cytokines, caspase-1 activity, and the number of pyroptosis cells (all P < 0.05). Conclusion:HBx may promote podocyte pyroptosis of HBV-GN via downregulating miRNA-223 targeting NLRP3 inflammasome, suggesting that miRNA-223 is expected to be a potential target for the treatment of HBV-GN.
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In recent years, with the development of metabolic reprogramming research, people have changed their understanding of the biological effects of immune cells. Under the stimulation of inflammatory response, immune cells re-regulate their metabolism and bioenergetics, provide energy and substrates for cell survival, and initiate immune effect functions. Nod-like receptor protein 3 (NLRP3) inflammasome, as an important component of the innate immune system, has been shown to sense metabolites such as uric acid and cholesterol crystals, and can be inhibited by metabolites such as ketones. It is also regulated by mitochondrial reactive oxygen species and glycolytic components (such as hexokinase). Recent studies have shown that a variety of metabolic pathways converge as effective regulators of NLRP3 inflammasome. The paper reviews the metabolic regulatory pathways and specificity of NLRP3 inflammasome activation, and its role in renal diseases.
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Objective:To explore the potential role of nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3)/GATA-binding protein 4 (GATA-4)/vascular endothelial growth factor (VEGF) signal pathway in neovascular age-related macular degeneration (nAMD).Methods:We applied the TRANSFAC Public database to search the human and mouse VEGF promoters and upstream transcription factors, analyzed the transcription factors that may influence the transcriptional activity of VEGF. The RAW264.7 cells were divided into control group and lipopolysaccharide (LPS) stimulated group (LPS group). Real time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to detect the activation of NLRP3 inflammasome, and the mRNA levels of GATA-4 and VEGFA. Thus, we applied the specific small molecular NLRP3 inhibitor MCC950 pretreated RAW264.7 cells (LPS+ MCC950 group), and detected the gene expression of NLRP3, Caspase-1, interleukin 1β( IL-1β), GATA-4 and VEGFA.Results:There were multiple GATA transcription factor binding sites upstream of human and mouse VEGF promoters. Compared with the control group, mRNA expression of NLRP3, Caspase-1, IL-1β, GATA-4 and VEGFA in LPS group were increased (all P<0.05). Compared with LPS group, mRNA expression of NLRP3, Caspase-1, IL-1β, GATA-4 and VEGFA in LPS+ MCC950 group were significantly decreased (all P<0.05). Conclusions:NLRP3/GATA-4/VEGF signal pathway may play a significant role in the pathologic processes of nAMD.
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Purpose: Myocardial ischemia/reperfusion injury (MIRI) leads to myocardial tissue necrosis, which will increase the size of myocardial infarction. The study examined the protective effect and mechanism of the Guanxin Danshen formula (GXDSF) on MIRI in rats. Methods: MIRI model was performed in rats; rat H9C2 cardiomyocytes were hypoxia-reoxygenated to establish a cell injury model. Results: The GXDSF significantly reduced myocardial ischemia area, reduced myocardial structural injury, decreased the levels of interleukin (IL-1ß, IL-6) in serum, decreased the activity of myocardial enzymes, increased the activity of superoxide dismutase (SOD), and reduced glutathione in rats with MIRI. The GXDSF can reduce the expression of nucleotide- binding oligomerization domain, leucine-rich repeat and pyrin domain containing nod-like receptor family protein 3 (NLRP3), IL-1ß, caspase-1, and gasdermin D (GSDMD) in myocardial tissue cells. Salvianolic acid B and notoginsenoside R1 protected H9C2 cardiomyocytes from hypoxia and reoxygenation injury and reduced the levels of tumor necrosis factor α (TNF-α) and IL-6 in the cell supernatant, decreasing the NLRP3, IL-18, IL-1ß, caspase-1, and GSDMD expression in H9C2 cardiomyocytes. GXDSF can reduce the myocardial infarction area and alleviate the damage to myocardial structure in rats with MIRI, which may be related to the regulation of the NLRP3. Conclusion: GXDSF reduces MIRI in rat myocardial infarction injury, improves structural damage in myocardial ischemia injury, and reduces myocardial tissue inflammation and oxidative stress by lowering inflammatory factors and controlling focal cell death signaling pathways.