Effect and mechanism of reactive oxygen species-mediated NOD-like receptor family pyrin domain-containing 3 inflammasome activation in hepatic alveolar echinococcosis

BACKGROUND The NOD-like receptor family pyrin domain-containing 3(NLRP3)inflammasome is a significant component of the innate immune system that plays a vital role in the development of various parasitic diseases.However,its role in hepatic alveolar echinococcosis(HAE)remains unclear.AIM To investigate the NLRP3 inflammasome and its mechanism of activation in HAE.METHODS We assessed the expression of NLRP3,caspase-1,interleukin(IL)-1β,and IL-18 in the marginal zone and corresponding normal liver of 60 patients with HAE.A rat model of HAE was employed to investigate the role of the NLRP3 inflammasome in the marginal zone of HAE.Transwell experiments were conducted to investigate the effect of Echinococcus multilocularis(E.multilocularis)in stimulating Kupffer cells and hepatocytes.Furthermore,immunohistochemistry,Western blotting,and enzyme-linked immunosorbent assay were used to evaluate NLRP3,caspase-1,IL-1β,and IL-18 expression;flow cytometry was used to detect apoptosis and reactive oxygen species(ROS).RESULTS NLRP3 inflammasome activation was significantly associated with ROS.Inhibition of ROS production decreased NLRP3-caspase-1-IL-1βpathway activation and mitigated hepatocyte damage and inflammation.CONCLUSION E.multilocularis induces hepatocyte damage and inflammation by activating the ROS-mediated NLRP3-caspase-1-IL-1βpathway in Kupffer cells,indicating that ROS may serve as a potential target for the treatment of HAE.

Efficacy of Jiangzhi Xiaoban tablet(降脂消斑片)on toll-like receptor 4/nuclear factor-kappa B/nod-like receptor protein 3 signaling pathway in mice with atherosclerosis induced by high-fat diet

OBJECTIVE:To study the effect of Jiangzhi Xiaoban tablet(降脂消斑片,JZXB)on toll-like receptor 4(TLR4)/nuclear factor-kappa B(NF-κB)/Nod-like receptor protein 3(NLRP3)signaling pathway expression in atherosclerosis(AS)mice by establishing a mouse model of AS,and to explore its mechanism of prevention and treatment of AS.METHODS:Sixty-four male C57BL/6J mice were randomly divided into two groups,12 in the normal control group and 52 in the model group(MOD).Seven weeks later,two mice in each of the above two groups were randomly sacrificed,and the whole aortic tissue of the mice was taken out for hematoxylin-eosin staining.After successful modeling,50 mice in the modeling group were randomly divided into 5 groups:MOD,atorvastatin group(ATO),low-dose group of JZXB(JZXB-L),middle-dose group of JZXB(JZXB-M),and high-dose group of JZXB(JZXB-H),10 mice in each group.The mice in each group were killed after 6 weeks of preventive administration.HE staining was used to observe the pathological changes of aorta in AS mice.The levels of serum triglyceride(TG),total cholesterol(TC),low-density lipoprotein cholesterol(LDL-C)and high-density lipoprotein cholesterol(HDL-C)were detected by automatic biochemical analyzer.The levels of inflammatory factor interleukin-1β(IL-1β)were detected by enzyme linked immunosorbent assay.The expression of TLR4,NF-κB and NLRP3 proteins in aortic tissue was detected by immunohistochemistry.RESULTS:Compared with the MOD,the levels of serum TC,TG and LDL-C in the JZXB-H and ATO were significantly decreased,while the level of HDL-C was significantly increased.The levels of serum TG,LDL-C in the JZXB-M were significantly decreased,and the level of HDL-C was significantly increased.Compared with the MOD,the levels of IL-1βwere significantly decreased,aortic lesions were significantly improved,and the expression of TLR4,NF-κB,and NLRP3 proteins in the aortic tissue was significantly decreased in the JZXB-H,JZXB-M,and ATO.CONCLUSION:JZXB has inhibitory effect on atherosclerosis in mice,and its mechanism may be through regulating the TLR4/NF-κB/NLRP3 signaling pathway and reducing the inflammatory response,so as to play a role in inhibiting atherosclerosis.

Two VOZ transcription factors link an E3 ligase and an NLR immune receptor to modulate immunity in rice

Nucleotide-binding leucine-rich repeat(NLR)proteins play critical roles in plant immunity.However,how NLRs are regulated and activate defense signaling is not fully understood.The rice(Oryza sativa)NLR receptor Piz-t confers broad-spectrum resistance to the fungal pathogen Magnaporthe oryzae and the RING-type E3 ligase AVRPIZ-T INTERACTING PROTEIN 10(APIP10)negatively regulates Piz-t accumulation.In this study,we found that APIP10 interacts with two rice transcription factors,VASCULAR PLANT ONEZINC FINGER 1(OsVOZ1)and OsVOZ2,and promotes their degradation through the 26S proteasome pathway.OsVOZ1 displays transcriptional repression activity while OsVOZ2 confers transcriptional activation activity in planta.The osvoz1 and osvoz2 single mutants display modest but opposite M.oryzae resistance in the non-Piz-t background.However,the osvoz1 osvoz2 double mutant exhibits strong dwarfism and cell death,and silencing of both genes via RNA interference also leads to dwarfism,mild cell death,and enhanced resistance to M.oryzae in the non-Piz-t background.Both OsVOZ1 and OsVOZ2 interact with Piz-t.Double silencing of OsVOZ1 and OsVOZ2 in the Piz-t background decreases Piz-t protein accumulation and transcription,reactive oxygen species-dependent cell death,and resistance to M.oryzae containing AvrPiz-t.Taken together,these results indicate that OsVOZ1 and OsVOZ2 negatively regulate basal defense but contribute positively to Piz-t-mediated immunity.

Ginsenoside Rb1 Reduces D-GalN/LPS-induced Acute Liver Injury by Regulating TLR4/NF-κB Signaling and NLRP3 Inflammasome

Background and Aims:The effect of ginsenoside Rb1 on D-galactosamine(D-GalN)/lipopolysaccharide(LPS)-induced acute liver injury(ALI)is unknown.The aim of this study was to evaluate the effect of ginsenoside Rb1 on ALI and its underlying mechanisms.Methods:Mice were pretreated with ginsenoside Rb1 by intraperitoneal injection for 3 days before D-GalN/LPS treatment,to induce ALI.The survival rate was monitored every hour for 24 h,and serum biochemical parameters,hepatic index and histopathological analysis were evaluated to measure the degree of liver injury.ELISA was used to detect oxidative stress and inflammatory cytokines in hepatic tissue and serum.Immunohistochemistry staining,RT-PCR and western blotting were performed to evaluate the expression of toll-like receptor 4(TLR4),nuclear factorkappa B(NF-κB),and NLR family,pyrin domain-containing 3 protein(NLRP3)in liver tissue and Kupffer cells(KCs).Results:Ginsenoside Rb1 improved survival with D-GalN/LPS-induced ALI by up to 80%,significantly ameliorated the increased alanine and aspartate transaminase,restored the hepatic pathological changes and reduced the levels of oxidative stress and inflammatory cytokines altered by D-GalN/LPS.Compared to the control group,the KCs were increased in the D-GalN/LPS groups but did not increase significantly with Rb1 pretreatment.D-GalN/LPS could upregulate while Rb1 pretreatment could downregulate the expression of interleukin(IL)-1β,IL-18,NLRP3,apoptosis associated specklike protein containing CARD(ASC)and caspase-1 in isolated KCs.Furthermore,ginsenoside Rb1 inhibited activation of the TLR4/NF-κB signaling pathway and NLRP3 inflammasome induced by D-GalN/LPS administration.Conclusions:Ginsenoside Rb1 protects mice against D-GalN/LPS-induced ALI by attenuating oxidative stress and the inflammatory response through the TLR4/NF-κB signaling pathway and NLRP3 inflammasome activation.

AstragalosideⅣplays a role in reducing radiation-induced liver inflammation in mice by inhibiting thioredoxin-interacting protein/nod-like receptor protein 3 signaling pathway

OBJECTIVE:To investigate the efficacy of Astragaloside IV(AS-IV)on radiation-induced liver inflammation in mice.METHODS:The mice were divided into normal group,dimethyl sulfoxide solvent group,irradiation group(IR),irradiation+AS-IV(20 mg/kg)group(IR+AS-20)and irradiation+AS-IV(40 mg/kg)group(IR+AS-40).One month after intraperitoneal injection of AS-IV,the mice were irradiated with 8Gry Co60γ,the blood was collected for biochemical analysis,and the liver was collected for hematoxylin-eosin staining,immunofluorescence and electron microscopic observation,oxidative stress,and Western blot analysis.RESULTS:The AS-IV treatment significantly ameliorated the pathological morphology of liver and reduced the alanine aminotransferase and aspertate aminotransferase levels in serum induced by radiation;AS-IV treatment also significantly reduced the expression of inflammatory factors tumor necrosis factor alpha and interleukin 6 and antagonized malonaldehyde content and superoxide dismutase activity in liver caused by radiation;in addition,AS-IV treatment can significantly inhibited the positive expression of thioredoxin-interacting protein(TXNIP)and nod-like receptor protein 3(NLRP3)inflammasome in liver tissue after radiation;The expression of TXNIP,NLRP3 inflammasome,apoptosisassociated speck-like protein containing a CARD,cysteinyl aspartate-specific proteinase 1 and interleukin 1beta in the AS-IV prevention group decreased significantly compared to the radiation group.CONCLUSIONS:These findings suggested that Co60γradiation can cause structural and functional damage to the liver,which may be related to the NLRP3 mediated inflammatory pathway;AS-IV may play a protective role by inhibiting the TXNIP/NLRP3 inflammasome signaling pathway in the radiation-induced liver injury model.

Sini powder ameliorates the inflammatory response in rats with stress-induced non-alcoholic fatty liver disease by inhibiting the nuclear factor kappa-B/pyrin domain-containing protein 3 pathway

OBJECTIVE: To evaluate the effectiveness of Sini powder for the treatment of non-alcoholic fatty liver disease(NAFLD) in rats and the molecular mechanisms involved.METHODS: A rat model of stress-induced NAFLD was established by a combination of long-term tethering and feeding of a high-fat, high-calorie diet. These rats were then intragastrically administered with either simvastatin, Sini powder, or vehicle for 1 week. The body mass and field test scores for each group were recorded weekly. Serum aspartate aminotransferase and alanine aminotransferase activities, and triglyceride, total cholesterol,and free fatty acid concentrations were measured.Liver tissue histopathology was examined on hematoxylin and eosin-stained paraffin sections and oil red O-stained frozen sections. The hepatic m RNA expression of nuclear factor kappa-B(NF-κB),NOD-, LRR-, and pyrin domain-containing protein 3(NLRP3), apoptosis-associated speck-like protein containing CARD(ASC), and caspase-1 were measured by reverse transcription-polymerase chain reaction(RT-PCR). The hepatic protein concentrations of NF-κB and NLRP3, ASC, caspase-1, interleukin-1β(IL-1β), interleukin-6(IL-6), and the serum concentrations of IL-1β and IL-6 were measured by enzyme-linked immunosorbent assay.RESULTS: Compared with the Blank group, rats in the Compound model group showed significant pathologic manifestations of NAFLD, and the expression of NF-κB, NLRP3, ASC, caspase-1, IL-1βand IL-6 were significantly higher(all P < 0.01). Both simvastatin and Sini powder significantly ameliorated the NAFLD pathology and the abnormal expression of NF-κB, NLRP3, ASC, caspase-1, IL-1β, and IL-6(all P < 0.01).CONCLUSION: Sini powder inhibits the inflamma-tory response in rats with NAFLD, which is mediated by NF-κB/NLRP3, IL-1β, and IL-6, reduces the effects of psychological stress, and improves lipid metabolism. Therefore, Sini powder may be effective for the treatment of stress-related NAFLD through multiple mechanisms.

Reduning plus ribavirin display synergistic activity against severe pneumonia induced by H1N1 influenza A virus in mice

OBJECTIVE:To investigate synergistic effect of Reduning(RDN)injection plus ribavirin against severe pneumonia induced by H1 N1 influenza A virus in mice.METHODS:We established a mouse model of severe pneumonia induced by influenza A virus by infecting Balb/c mice with CA07 virus.We randomly assigned the infected mice into four groups,and treated them with normal saline(NS group),RDN(injection,86.6 mg/kg),ribavirin(injection,66.6 mg/kg)or double Ribavirin plus RDN group,the same dosage as used in the single treatments)for 5 d.Lung index and lung pathology were recorded or calculated in terms of the curative effective.Cytokines,NOD-like receptor family pyrin domain containing 3(NLRP3)inflammasome related protein including caspase-associated recruitment domain(CARD)domain Apoptosis-associated speck-like protein containing a caspase recruitment domain(ASC),caspase-1 and NOD-like receptor family,pyrin domain containing 3(NLRP3),and reactive oxygen species were simultaneously investigated.RESULTS:RDN plus ribavirin treatment,not RDN or ribavirin alone,provided a significant survival benefit to the influenza A virus-infected mice.The combination treatment protected the mice against severe influenza infection by attenuating the severe lung injury.The combined treatment also reduced the viral titers in mouse lungs and lung index,downregulated their immunocytokine levels,including IL-1βand IL-18,and down regulated the NLRP3,especially the transcription and translation of caspase-1.Meanwhile NS group had significantly higher reactive oxygen species(ROS)expression which could was dramatically reduced by the treatment of RDN plus ribavirin.CONCLUSION:Our study showed that RDN combined with ribavirin could protect the mice,and reduce the lung immunopathologic damage caused by severe influenza pneumonia.The mechanism could be that it reduced ROS produce and inhibited NLRP3 inflammasome activation so that mainly lower the downstream inflammatory cytokines IL-1βand IL-18.

Qingre Jianpi decoction(清热健脾汤)attenuates inflammatory responses by suppressing NOD-like receptor family pyrin domain-containing 3 inflammasome activation in dextran sulfate sodium-induced colitis mice

OBJECTIVE:To investigate the effects of Qingre Jianpi decoction(清热健脾汤,QRJPD)on dextran sulfate sodium(DSS)-induced colitis mice and explore its mechanism.METHODS:All mice were randomly divided into six groups.Weight changes,disease activity index values,and histological damage were detected.Inflammatory cytokines and immune cell infiltration were measured using enzyme-linked immunosorbent assays(ELISA)and immunohistochemistry(IHC)method.The key protein expression levels of the NOD-like receptor family pyrin domain-containing 3(NLRP3)inflammasome were detected by western blot analysis,IHC,and quantitative reverse transcription polymerase chain reaction.RESULTS:QRJPD played an anti-inflammatory role in the treatment of ulcerative colitis(UC),reduced the secretion of inflammatory cytokines,and inhibited the inflammatory infiltration of immune cells by suppressing DSS-induced activation of the NLRP3 inflammasome.CONCLUSION:QRJPD exerts protective effects by inhibiting DSS-induced NLRP3 inflammasome activation.