Morroniside ameliorates lipopolysaccharide-induced inflammatory damage in iris pigment epithelial cells through inhibition of TLR4/JAK2/STAT3 pathway

AIM:To investigate the effect of morroniside(Mor)on lipopolysaccharide(LPS)-treated iris pigment epithelial cells(IPE).METHODS:IPE cells were induced by LPS and treated with Mor.Cell proliferation was detected by cell counting kit(CCK)-8,apoptosis was detected by flow cytometry,the levels of tumor necrosis factor-α(TNF-α),interleukin(IL)-6,and IL-8 were measured by enzyme-linked immunosorbent assay(ELISA)kits,and the protein expression of TLR4,JAK2,p-JAK2,STAT3,and p-STAT3 was analyzed by Western blotting.In addition,overexpression of TLR4 and Mor treatment of LPS-stimulated IPE cells were also tested for the above indices.RESULTS:Mor effectively promoted the proliferation and inhibited the apoptosis of LPS-treated IPE cells.In addition,Mor significantly reduced the levels of TNF-α,IL-6,and IL-8 and significantly inhibited the expression of TLR4,p-JAK2,and p-STAT3 in LPS-treated IPE cells.The effect of Mor on LPS-treated IPE cells was markedly attenuated after overexpression of TLR4.CONCLUSION:These findings suggest that Mor may ameliorate LPS-induced inflammatory damage and apoptosis in IPE through inhibition of TLR4/JAK2/STAT3 pathway.

Quercetin regulates depression-like behavior in CUMS rat models via TLR4/NF-κB signaling

Background:Depression is becoming increasingly prevalent around the world,imposing a substantial burden on individuals,families,as well as society.Quercetin is known to be highly effective in treating depression.However,additional research is needed to dissect the mechanisms of its anti-depressive effects.Methods:For this study,Sprague-Dawley(SD)rats were randomized into the control,model,quercetin,or fluoxetine group.The latter three groups were exposed to chronic unpredictable mild stress(CUMS)for 42 d.The first two groups received saline solution daily via oral gavage.Meanwhile,the quercetin group was orally administered a quercetin suspension(52.08 mg/kg)every day,while the fluoxetine group was orally administered a fluoxetine solution(2.08 mg/kg).Here,fluoxetine served as the positive control drug to compare the therapeutic effects of quercetin.The experimental period was 6 weeks.Depressive behaviors in rats were assessed through various physiological and behavioral measures.Additionally,pathological changes in hippocampal tissues were examined using Nissl staining.Serum cytokines were detected using an enzymelinked immunosorbent assay(ELISA),and immunohistochemistry was employed to quantify the levels and integral optical density(IOD)values of ionized calcium binding adaptor molecule-1(Iba-1)expression in the brain.Real-time fluorescence quantitative PCR(RT-qPCR)was utilized to evaluate the mRNA levels of inflammatory indicators as well as toll-like receptor 4(TLR4),and nuclear factor-κappa B P65(NF-κB P65)in hippocampus.Western blot(WB)technique was employed to observe the protein levels of TLR4,NF-κB P65,and phospho-NF-κB P65(p-NF-κB P65).Results:After 42 d of exposure to CUMS,rats exhibited a slow increase in body weight,a reduction in food intake,an abnormal preference for sugar water,and aberrant open-field behaviors.Pathological analysis revealed the disintegration,rupture,interruption,and disorganization of hippocampal neuronal cells after CUMS exposure,along with a decrease in Nissl bodies in the CA1 region.This was accompanied by the elevated expression of interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α),and interleukin-6(IL-6)in the serum and the upregulation of IL-1β,IL-6,and TNF-αmRNA expression in the hippocampus.Increases in Iba-1-positive cells and the IOD values of Iba-1 were detected in hippocampal microglia.Furthermore,TLR4 and NF-κB P65 mRNA and protein levels were upregulated in hippocampal tissues.Quercetin,an antidepressant,could alleviate depression-like symptoms in rats and downregulate inflammatory factors associated with the TLR4/NF-κB signaling pathway in hippocampal microglia,and its therapeutic effect was comparable to fluoxetine.Conclusion:In rat models of CUMS,quercetin may act as an antidepressant by inhibiting inflammation in hippocampal microglia via TLR4/NF-κB signaling pathway.These results offer experimental and theoretical support for applying quercetin in the clinical management of depression.

TRDMT1 exhibited protective effects against LPS-induced inflammation in rats through TLR4-NF-κB/MAPK-TNF-αpathway

Background:Inflammation is a complex physiological and pathological process.Although many types of inflammation are well characterized,their physiological func-tions are largely unknown.tRNA aspartic acid methyltransferase 1(TRDMT1)has been implicated as a stress-related protein,but its intrinsic biological role is unclear.Methods:We constructed a Trdmt1 knockout rat and adopted the LPS-induced sepsis model.Survival curve,histopathological examination,expression of inflammatory fac-tors,and protein level of TLR4 pathway were analyzed.Results:Trdmt1 deletion had no obvious impact on development and growth.Trdmt1 de-letion slightly increased the mortality during aging.Our data showed that Trdmt1 strongly responded in LPS-treated rats,and Trdmt1 knockout rats were vulnerable to LPS treat-ment with declined survival rate.We also observed more aggravated tissue damage and more cumulative functional cell degeneration in LPS-treated knockout rats compared with control rats.Further studies showed upregulated TNF-αlevel in liver,spleen,lung,and serum tissues,which may be explained by enhanced p65 and p38 phosphorylation.Conclusions:Our data demonstrated that Trdmt1 plays a protective role in inflamma-tion by regulating the TLR4-NF-κB/MAPK-TNF-αpathway.This work provides useful information to understand the TRDMT1 function in inflammation.

Anti-inflammation Effects of Sinomenine on Macrophages through Suppressing Activated TLR4/NF-kB Signaling Pathway

Sinomenine(SN)has been used in the clinical treatment of systemic lupus erythematosus and rheumatoid arthritis for many years.Studies showed that SN held protective effects such as anti-inflammation,scavenging free radicals and suppressing immune response in many autoimmune diseases.The purpose of the present study is to explore the mechanism of anti-inflammation of SN on lipopolysaccharide(LPS)-induced macrophages activation and investigate whether the TLR4/NF-κB signaling pathway participated in.Macrophages isolated from mouse peritoneal cavity were stimulated by 1 pg/mL LPS for 24 h.And then the cells were treated with various concentrations of SN,TLR4 inhibitor respectively for additional 48 h.Drug toxicity was detected by MTT assay and Transwell experiment was used to assess chemotaxis.Furthermore,TLR4 and MyD88 mRNA levels were detected by real-time PCR.Western blotting was used to examine TLR4,MyD88 and phosphorylated IκB protein expression in macrophages.Immunofluorescence assay was applied to observe p65 NF-κB protein expression in macrophage nucleus.We extracted macrophages with high purity and activity from the abdominal cavity of mice.SN remarkably inhibited the chemotaxis and secretion function of LPS-stimulated macrophages.It also down-regulated both the protein levels of inflammatory cytokines(TNF-α,IL-β and IL-6)and the RNA and protein levels of the key factors(TLR4,MyD88,p-IkB)in TLR4 pathway.The expression of p65 NF-κB protein in nuclei was down-regulated,which was correlated with a similar decrease in p-IκB protein level.In conclusion,SN can inhibit the LPS induced immune responses in macrophages by blocking the activated TLR4/NF-κB signaling pathway.These results may provide a therapeutic approach to regulate inflammatory responses.

Milled flaxseed-added diets ameliorated hepatic inflammation by reducing gene expression of TLR4/NF-κB pathway and altered gut microbiota in STZ-induced type 1 diabetic mice

Flaxseed has displayed the potential beneficial as functional foods.However,most studies focused on effects of flaxseed extracts or ingredients in flaxseed.Besides,few studies showed that flaxseed extracts contributed to anti-type 1 diabetes(T1D),yet the underlying mechanism is still unknown.In the present study,16.7% of milled flaxseed(MF)-added diet was given to diabetic mice induced by streptozocin for 6 weeks.The results showed that MF feeding 1)slightly decreased blood glucose levels and improved the ability of glucose tolerance by oral glucose tolerance test,2)decreased liver tumor necrosis factor-αlevels and increased liver glycogen levels with significance via down-regulating TLR4/NF-κB pathways,3)and significantly altered some beneficial bacteria in gut microbiota.In conclusion,the present study showed that milled flaxseed showed the potential on anti-T1D through anti-inflammation via TLR4/NF-κB and altering the gut microbiota in STZ-induced diabetic mice.

Ramulus Cinnamomi extract attenuates neuroinflammatory responses via downregulating TLR4/MyD88 signaling pathway in BV2 cells

Ramulus Cinnamomi （RC）, a traditional Chinese herb, has been used to attenuate inflammatory responses. The purpose of this study was to investigate the effect of RC extract on lipopolysaccharide （LPS）-induced neuroinflammation in BV2 microglial cells and the underlying mechanisms involved. BV2 cells were incubated with normal medium （control group）, LPS, LPS plus 30 pg/mL RC extract, or LPS plus 100 pg/mL RC extract. The BV2 cell morphology was observed under an optical microscope and cell viability was detected by MTT assay. Nitric oxide level in BV2 cells was detected using Griess regents, and the levels of interleukin-6, interleukin-1 β, and tumor necrosis factor u in BV2 cells were determined by ELISA. The expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 proteins were detected by western blot assay. Compared with the LPS group, both 30 and 100 μg/mL RC extract had no significant effect on the viability of BV2 cells. The levels of nitric oxide, interleukin-6, interleukin-1β and tumor necrosis factor ct in BV2 cells were all significantly increased after LPS induction, and the levels were significantly reversed after treatment with 30 and 100 μg/mL RC extract. Furthermore, RC extract significantly inhibited the protein expression levels of cyclooxygenase-2, Toll-like receptor 4 and myeloid differentiation factor 88 in LPS-induced BV2 cells. Our findings suggest that RC extract alleviates neuroinflammation by downregulating the TLR4/MyD88 signaling pathway.

Research Progress and Research Ideas on Anti-hepatic Fibrosis and Promoting Blood Circulation and Removing Blood Stasis of the National Drug Plumbapin Based on TLR4 Signal Pathway

Hepatic fibrosis is a reversible pathological phenomenon in the early and middle stages,but but no satisfactory intervention drugs have been available so far.Recent studies have suggested that microcirculation disturbance of liver is one of the important pathogenesis of chronic liver disease,the improvement of microcirculation is beneficial to the recovery of liver function and the delay of liver fibrosis.Hepatic stellate cells are the core cells of hepatic fibrosis,and also the most critical cells that affect the microcirculation of the liver.While TLR4/MyD88/NF-κB and TLR4/MyD88/MAPKs which are based on the action of hepatic stellate cells are two pathways that have very important influence on the inflammatory response of liver,the proliferation and apoptosis of hepatic stellate cells,and the secretion of fibrogenic cytokines.It was found that Plumbapin,the active ingredient of Guangxi specialty ethnic medicine,has the definite effect of promoting blood circulation and removing blood stasis and anti-hepatic fibrosis,but its mechanism is not clear.In this study,the research progress of the above problems was reviewed,and further research ideas were derived as follows:the pharmacological effect of Plumbapin on anti-hepatic fibrosis,promoting blood circulation and removing stasis was based on the influence of TLR4/MyD88/NF-κB and MAPKs signal pathway.

Effects of Polysaccharides from Dicliptera chinensis(L.)Nees.on TLR4/NF-κB Signaling Pathway in Cell Model of Non-alcoholic Fatty Liver

[Objectives]To observe the effects of polysaccharides from Dicliptera chinensis(L.)Nees.on the expression of TLR/NF-κB pathway related proteins in HepG2 cells induced by oleic acid,and to explore the possible mechanism of polysaccharides from D.chinensis(L.)Nees.in the treatment of non-alcoholic fatty liver disease(NAFLD).[Methods]HepG2 cells were induced with oleic acid to establish a non-alcoholic fatty liver cell model.After intervention with 0.25 and 0.5 mg/mL of D.chinensis(L.)Nees.polysaccharides,the ALT and AST activity and TG and TC contents were detected with kits,and the changes in the expression of CDK5,TLR4,p-NF-κB and NF-κB were analyzed using Western-blotting.[Results]In the HepG2 cells induced with oleic acid,the ALT and AST activity increased significantly,the TG and TC contents increased significantly,and the expression levels of CDK5,TLR4 and p-NF-κB proteins up-regulated significantly.In the HepG2 cells intervened with D.chinensis(L.)Nees.polysaccharides,the activity of ALT and AST,the contents of TG and TC,and the expression levels of CDK5,TLR4 and p-NF-κB proteins all reduced significantly.[Conclusions]Polysaccharides from D.chinensis(L.)Nees.may interfere with NAFLD by inhibiting the TLR4/NF-κB pathway.

Bioinformatic Analysis and Experimental Verification of QJHGD on Caerulein-induced Inflammatory Response in SAP Model Rats Based on TLR4/NF-κB/My D88 Pathway

[Objectives]To conduct bioinformatic analysis and experimental verification of Qingjie Huagong Decoction(QJHGD)on caerulein-induced inflammatory response in severe acute pancreatitis(SAP)model rats based on TLR4/NF-κB/MyD88 pathway.[Methods]The effective component groups and potential targets of QJHGD were collected by the network pharmacology method.A drug-component-target network was constructed.The GO and KEGG of targets were enriched and analyzed with the aid of Metascape database,and the target pathway related to SAP inflammation was screened.The SAP rat model was established by caerulein combined with lipopolysaccharide,and QJHGD was intragastrically administered.Pancreatic tissue was observed by HE staining.In addition,enzyme-linked immunosorbent assay and immunohistochemistry were used to verify the anti-inflammatory effect of QJHGD on SAP rats and its regulatory effect on TLR4/NF-κB/MyD88 target pathway.[Results]A total of 105 active components of QJHGD and 148 key targets of SAP were predicted and screened;KEGG was enriched in 320 different pathways including toll-like receptor and NF-κB classical pathways.Animal experiment verified that QJHGD reduced serum amylase,serum lipase activity,IL-6,TNF-αlevels in SAP rats;HE staining showed the effect of QJHGD on the pathological changes of pancreas,and QJHGD inhibited the positive expression of key proteins of TLR4,NF-κB and MyD88 in the inflammatory transduction pathway.[Conclusions]The mechanism of QJHGD improving pancreatic injury in SAP rats may be related to down-regulating the expression of key proteins in the TLR4/NF-κB/MyD88 pathway.

Blautia producta displays potential probiotic properties against dextran sulfate sodium-induced colitis in mice

Blautia has attracted attention because of its potential efficacy in ameliorating host energy metabolism and inflammation.This study aims to investigate the influences of Blautia producta D4 on colitis induced by dextran sulfate sodium(DSS)and to reveal the underlying mechanisms.Results showed that B.producta D4 intervention significantly relieved body weight loss,and suppressed the elevation of pro-inflammatory cytokines(including interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),and interleukin-1β(IL-1β))and excessive oxidative stress(myeloperoxidease(MPO)activity,superoxide dismutase(SOD)activity,glutathione peroxidase(GSH-Px)activity,and malondialdehyde(MDA)level)in colitis mice.Moreover,the concentrations of tight junction proteins(occludin,claudin-1,and ZO-1)related to the intestinal barrier were obviously elevated,and colitis-related TLR4/NF-κB pathway activation was remarkably inhibited after B.producta D4 intervention.The intestinal microbial disorder was evidently ameliorated by increasing the relative abundance of Clostridium sensu stricto 1,Bifidobacterium,GCA-900066225,Enterorhabdus,and reducing the relative abundance of Lachnospiraceae NK4A136 group.In conclusion,oral administration of B.producta D4 could ameliorate DSS-induced colitis by suppressing inflammatory responses,maintaining the intestinal barrier,inhibiting TLR4/NF-κB pathway,and regulating intestinal microbiota balance.These results are conducive to accelerate the development of B.producta D4 as a functional probiotic for colitis.

Elaidic acid-induced intestinal barrier damage led to gut-liver axis derangement and triggered NLRP3 inflammasome in the liver of SD rats

Previous studies have shown that trans fatty acids(TFA) are associated with several chronic diseases,the gut microbiota is directly influenced by dietary components and linked to chronic diseases.Our research investigated the effects of elaidic acid(EA),a typical TFA,on the gut microbiota to understand the underlying mechanisms of TFA-related chronic diseases.16S rDNA gene sequencing on faecal samples from Sprague-Dawley rats were performed to explore the composition change of the gut microbiota by EA gavage for 4 weeks.The results showed that the intake of EA increased the abundance of well-documented harmful bacteria,such as Proteobacteria,Anaerotruncus,Oscillibacter and Desulfovibrionaceae.Plus,EA induced translocation of lipopolysaccharides(LPS) and the above pathogenic bacteria,disrupted the intestinal barrier,led to gut-liver axis derangement and TLR4 pathway activation in the liver.Overall,EA induced intestinal barrier damage and regulated TLR4-MyD88-NF-κB/MAPK pathways in the liver of SD rats,leading to the activation of NLRP3 inflammasome and inflammatory liver damage.

Huoxin Pill Reduces Myocardial Ischemia Reperfusion Injury in Rats via TLR4/NFκB/NLRP3 Signaling Pathway

Objective:To explore the protective effect of Huoxin Pill(HXP)on acute myocardial ischemia-reperfusion(MIRI)injury in rats.Methods:Seventy-five adult SD rats were divided into the sham-operated group,model group,positive drug group(diltiazem hydrochloride,DH),high dose group(24 mg/kg,HXP-H)and low dose group(12 mg/kg,HXP-L)of Huoxin Pill(n=15 for every group)according to the complete randomization method.After 1 week of intragastric administration,the left anterior descending coronary artery of the rat's heart was ligated for 45 min and reperfused for 3 h.Serum was separated and the levels of creatine kinase(CK),creatine kinase isoenzyme(CK-MB)and lactate dehydrogenase(LDH),superoxide dismutase(SOD),and malondialdehyde(MDA),hypersensitive C-reactive protein(hs-CRP)and interleukin-1β(IL-1β)were measured.Myocardial ischemia rate,myocardial infarction rate and myocardial no-reflow rate were determined by staining with Evans blue and 2,3,5-triphenyltetrazolium chloride(TTC).Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform(TCMSP)and Bioinformatics Analysis Tool for Molecular mechANism of Traditional Chinese Medicine(BATMAN)databases were used to screen for possible active compounds of HXP and their potential therapeutic targets;the results of anti-inflammatory genes associated with MIRI were obtained from GeneC ards,Drugbank,Online Mendelian Inheritance in Man(OMIM),and Therapeutic Target Datebase(TTD)databases was performed;Gene Ontology(GO)and Kyoto Encyclopedia of Genes and Genomes(KEGG)enrichment were used to analyze the intersected targets;molecular docking was performed using AutoD ock Tools.Western blot was used to detect the protein expression of Toll-like receptor 4(TLR4)/nuclear factor kappa-B(NFκB)/NOD-like receptor protein 3(NLRP3).Results:Compared with the model group,all doses of HXP significantly reduced the levels of LDH,CK and CK-MB(P<0.05,P<0.01);HXP significantly increased serum activity of SOD(P<0.05,P<0.01);all doses of HXP significantly reduced the levels of hs-CRP and IL-1β(P<0.05,P<0.01)and the myocardial infarction rate and myocardial no-reflow rate(P<0.01).GO enrichment analysis mainly involved positive regulation of gene expression,extracellular space and identical protein binding,KEGG pathway enrichment mainly involved PI3K-Akt signaling pathway and lipid and atherosclerosis.Molecular docking results showed that kaempferol and luteolin had a better affinity with TLR4,NFκB and NLRP3 molecules.The protein expressions of TLR4,NFκB and NLRP3 were reduced in the HXP group(P<0.01).Conclusions:HXP has a significant protective effect on myocardial ischemia-reperfusion injury in rats,and its effect may be related to the inhibition of redox response and reduction of the inflammatory response by inhibiting the TLR4/NFκB/NLRP3 signaling pathway.

Modulating effects of Astragalus polysaccharide on immune disorders via gut microbiota and the TLR4/NF-κB pathway in rats with syndrome of dampness stagnancy due to spleen deficiency

The syndrome of dampness stagnancy due to spleen deficiency(DSSD)is relatively common globally.Although the pathogenesis of DSSD remains unclear,evidence has suggested that the gut microbiota might play a significant role.Radix Astragali,used as both medicine and food,exerts the effects of tonifying spleen and qi.Astragalus polysaccharide(APS)comprises a macromolecule substance extracted from the dried root of Radix Astragali,which has many pharmacological functions.However,whether APS mitigates the immune disorders underlying the DSSD syndrome via regulating gut microbiota and the relevant mechanism remains unknown.Here,we used DSSD rats induced by high-fat and low-protein(HFLP)diet plus exhaustive swimming,and found that APS of moderate molecular weight increased the body weight gain and immune organ indexes,decreased the levels of interleukin-1β(IL-1β),IL-6,and endotoxin,and suppressed the Toll-like receptor 4/nuclear factor-κB(TLR4/NF-κB)pathway.Moreover,a total of 27 critical genera were significantly enriched according to the linear discriminant analysis effect size(LEfSe).APS increased the diversity of the gut microbiota and changed its composition,such as reducing the relative abundance of Pseudoflavonifractor and Paraprevotella,and increasing that of Parasutterella,Parabacteroides,Clostridium XIVb,Oscillibacter,Butyricicoccus,and Dorea.APS also elevated the contents of short-chain fatty acids(SCFAs).Furthermore,the correlation analysis indicated that 12 critical bacteria were related to the body weight gain and immune organ indexes.In general,our study demonstrated that APS ameliorated the immune disorders in DSSD rats via modulating their gut microbiota,especially for some bacteria involving immune and inflammatory response and SCFA production,as well as the TLR4/NF-κB pathway.This study provides an insight into the function of APS as a unique potential prebiotic through exerting systemic activities in treating DSSD.

Salvianolic Acid B Inhibits the TLR4-NFκ B-TNFα Pathway and Attenuates Neonatal Rat Cardiomyocyte Injury Induced by Lipopolysaccharide

Objective： To investigate the role of the TLR4-NF K B-TNFa inflammation pathway on lipopolysaccharide （LPS）-induced neonatal rat cardiomyocyte injury and the possible protective effects of salvianolic acid B （Sal B）. Methods： Wistar rat （1-2 days old） cardiomyocytes were isolated and cultured. Sal B 10-5mol/L, 10-6mol/L and 10-7mol/L were pro-treated for 6 h in the culture medium. LPS （1 μg/mL） was added to the culture medium and kept for 6 h to induce inflammation injury. The concentration of lactate dehydrogenase （LDH） in the supernatant was detected by spectrophotometry. The concentrations of tumor necrosis factor （TNF a） and heat shock protein 70 （HSP70） in the supernatant were detected by enzyme linked immunosorbent assay. The protein expressions of toll, such as receptor 4 （TLR4） and nuclear factor kappa B （NF K B） were detected by immunohistochemistry. The mRNA expressions of TLR4 and NF K B were detected by realtime reverse transcription polymerase chain reaction （RT-PCR）. Results： （1） The concentrations of LDH and TNF a in the LPS control group were significantly higher than those in the control group （561.41 ± 67,39 U/L and 77.94± 15.08 pg/mL, versus 292.13± 26.02 U/L and 25.39 ±16.53 pg/mL, respectively, P〈0.01, P〈0.05）. Compared with the LPS control group, the concentrations of LDH and TNF α were significantly decreased in the Sal B 10-5mol/L pro-treated group （451.76 ± 83.96 U/L and 34.00± 10.38 pg/mL, respectively, P〈0.05）. （2） The TLR4 and NF K B protein expression area in the LPS control group were significantly higher than those in the control group （1712.41 ± 410.12 μm2 and 2378.15 ± 175.29 μm2, versus 418.62 ± 24.42 μ m2 and 1721.74 ± 202.87μ m2, respectively, P〈0.01）. The TLR4 and NF K B protein expression internal optical density （IOD） values in the LPS control group were also significantly higher than those in the control group （3.06 ±0.33 and 7.20± 1.04, versus 0.91 ±0.21 and 4.24±0.48, respectively, P〈0.05 and P〈0.01）. Compared with the LPS control group, the TLR4 and NF K B protein expression areas were significantly decreased in the Sal B 10Smol/L pre-treated group （1251.54± 133.82 μ m2 and 1996.37 ± 256.67 μ m2, respectively, P〈0.05）, the TLR4 and NF K B protein expression IOD values were also significantly decreased in the Sal B 10-5mol/L pretreated group （1.92 ±0.28 and 5.17 ±0.77, respectively, P〈0.05）. （3） The TLR4 and NF K B mRNA expressions （2△△CT value） in the LPS control group were significantly higher than those in the control group （3.16 ± 0.38 and 5.03±0.43 versus 1.04±0.19 and 1.08±0.21, respectively, P〈0.01）. Compared with the LPS control group, the TLR4 and NF KB mRNA expressions （2△△CT value） were significantly decreased in the Sal B 10-5mol/L pre- treated group （1.34 ±0.22 and 1.74 ± 0.26, respectively, P〈0.05）. The concentration of HSP70 did not show any statistical differences in all groups （P〉0.05）. Conclusions： The TLR4-NF K B-TNF α pathway was quickly activated and was independent of HSP70 in the early phase of neonatal cardiomyocyte injury induced by LPS. The protective effects of Sal B may be through inhibiting the TLR4-NF K B-TNF a pathway and are dose-dependent.

Novel compound FLZ alleviates rotenoneinduced PD mouse model by suppressing TLR4/MyD88/NF-kB pathway through microbiotaegutebrain axis

Parkinson’s disease(PD)is the second most common neurodegenerative disease,but none of the current treatments for PD can halt the progress of the disease due to the limited understanding of the pathogenesis.In PD development,the communication between the brain and the gastrointestinal system influenced by gut microbiota is known as microbiota-gut-brain axis.However,the explicit mechanisms of microbiota dysbiosis in PD development have not been well elucidated yet.FLZ,a novel squamosamide derivative,has been proved to be effective in many PD models and is undergoing the phase I clinical trial to treat PD in China.Moreover,our previous pharmacokinetic study revealed that gut microbiota could regulate the absorption of FLZ in vivo.The aims of our study were to assess the protective effects of FLZ treatment on PD and to further explore the underlying microbiota-related mechanisms of PD by using FLZ as a tool.In the current study,chronic oral administration of rotenone was utilized to induce a mouse model to mimic the pathological process of PD.Here we revealed that FLZ treatment alleviated gastrointestinal dysfunctions,motor symptoms,and dopaminergic neuron death in rotenone-challenged mice.16 S rRNA sequencing found that PD-related microbiota alterations induced by rotenone were reversed by FLZ treatment.Remarkably,FLZ administration attenuated intestinal inflammation and gut barrier destruction,which subsequently inhibited systemic inflammation.Eventually,FLZ treatment restored blood-brain barrier structure and suppressed neuroinflammation by inhibiting the activation of astrocytes and microglia in the substantia nigra(SN).Further mechanistic research demonstrated that FLZ treatment suppressed the TLR4/MyD88/NF-κB pathway both in the SN and colon.Collectively,FLZ treatment ameliorates microbiota dysbiosis to protect the PD model via inhibiting TLR4 pathway,which contributes to one of the underlying mechanisms beneath its neuroprotective effects.Our research also supports the importance of microbiota-gut-brain axis in PD pathogenesis,suggesting its potential role as a novel therapeutic target for PD treatment.

Hepatic protective effects of Shenling Baizhu powder, a herbal compound, against inflammatory damage via TLR4/NLRP3 signalling pathway in rats with nonalcoholic fatty liver disease

Objective: High-fat diet(HFD) and inflammation are two key contributors to nonalcoholic fatty liver disease(NAFLD). Shenling Baizhu powder(SLBZP), a classical herbal compound, has been successfully used to alleviate NAFLD. However, its specific mechanisms are not fully understood. In this study, we assessed the anti-NAFLD effect of SLBZP in vivo.Methods: Rats were fed an HFD with or without SLBZP or with probiotics. At the end of week 16, an echo magnetic resonance imaging(EchoMRI) body composition analyser was used to quantitatively analyse body composition;a micro-computed tomography(micro-CT) imaging system was used to evaluate whole body and liver fat;and the Moor full-field laser perfusion imager 2 was used to assess liver microcirculation, after which, all rats were sacrificed. Then, biochemical indicators in the blood and the ultrastructure of rat livers were evaluated. Protein expression related to the liver Toll-like receptor 4(TLR4)/Nod-like receptor family pyrin domain-containing 3(NLRP3) signalling pathway was assessed using Western blot analysis. Further, high-throughput screening of 29 related inflammatory factors in liver tissue was performed using a cytokine array.Results: SLBZP supplementation reduced body weight, serum free fatty acid, and insulin resistance index(P<0.05). It also ameliorated liver microcirculation and ultrastructural abnormalities. EchoMRI and micro-CT quantitative analyses showed that treatment with SLBZP reduced fat mass and visceral fat(P<0.05 and P<0.01, respectively). In addition, SLBZP decreased the expression of lipopolysaccharide(LPS)-activated TLR4/NLRP3 signalling pathway-related proteins and altered the expression levels of some inflammatory cytokines in liver tissues.Conclusion: SLBZP can inhibit NLRP3 inflammasome activation and interleukin-1 b release by suppressing LPS-induced TLR4 expression in rats with HFD-induced NAFLD. Thus, SLBZP may be beneficial for the prevention and treatment of inflammatory damage and associated diseases.

Inhibition of miR-873 provides therapeutic benefit in lipopolysaccharide-induced Parkinson disease animal model

OBJECTIVE Neuroinflammation plays a critical role in neurodegenerative disorders,although the inflammation may not the initiating factor.Parkinson disease(PD)is characterized pathologically by the accumulation of alpha synuclein(α-syn)and the loss of the dopamine(DA)neurons in the substantia nigra(SN),which has been reported to be induced by the stereotaxic injection of lipopolysaccharide(LPS)to the SN region in rodents.This study is to investigate the therapeutic benefit of the inhibition of miR-873 in PD.METHODS Rats received the right-unilaterally injection with concentrated LV-sponge or LV-EGFP 3 d before LPS treatment,7 or 14 d after LPS treatment.The animals were tested for rotational behavior with the dopaminergic agonist apomorphine dissolved in sterile saline at 21 d after LPS injection.The regulation of miR-873 on the genes related with cholesterol transport and inflammation was assayed in SH-SY5Y cells and U251 cells.RESULTS TLR4-My D88 signaling pathway was involved the regulation of miR-873 by LPS.The luciferase assay showed that HMGCR,ABCA1 and A20 were down-stream genes of miR-873.The transfection of miR-873 decreased the cholesterol levels in cell membrane,but increased in lysosome in SH-SY5Y cells.Compared with the control SH-SY5Y cells,cholesterol levels were higher in lysosome withα-synuclein overexpression or LPS treatment.The transfection of miR-873 increased theα-syn levels in lysosome in cel s withα-synuclein overexpression.The loss of dopaminergic neuorns induced by LPS was significantly respectively decreased by 22.8%,35.6%and 57% after the inhibition of miR-873 at 3 d before LPS treatment,7 or14 d after LPS treatment.Compared with LPS-treated group,the number of the rotation of rats was decreased by 60.4%,33.5%and 13.2%after the inhibition of miR-873 at 3 d before LPS treatment,7or 14 d after LPS treatment.The inhibition of miR-873 significantly decreased accumulation ofα-syn.The m RNA levels of HMGCR,ABCA1 and A20 in SN were decreased by LPS treatment,which was attenuated by the injection of LV-sponge.CONCLUSION The selective regulation of miR-873 can protect the dopaminergic neurons from the LPS-induced damage.The inhibition of miR-873 can attenuate the relocation of cholesterol in lysosome and the accumulation ofα-syn in neurons induced by LPS via the regulation of HMGCR,ABCA1 and A20.

ATF4 is directly recruited by TLR4 signaling and positively regulates TLR4-trigged cytokine production in human monocytes

Toll-like receptors （TLRs） are sentinels of the host defense system, which recognize a large number of microbial pathogens. The host defense system may be inefficient or inflammatory diseases may develop if microbial recognition by TLRs and subsequent TLR-triggered cytokine production are deregulated. Activating transcription factor 4 （ATF4）, a member of the ATF/CREB transcription factor family, is an important factor that participates in several pathophysiological processes. In this report, we found that ATF4 is also involved in the TLR-mediated innate immune response, which participates in TLR4 signal transduction and mediates the secretion of a variety of cytokines. We observed that ATF4 is activated and translocates to the nucleus following l ipopolysaccharide （LPS） stimulation via the TLR4-MyD88-dependent pathway. Additionally, a cytokine array assay showed that some key inflammatory cytokines, such as I L-6, I L-8 and RANTES, are positively regulated by ATF4. We also demonstrate that c-Jun directly binds to ATF4, thereby promoting the secretion of inflammatory cytokines. Taken together, these results indicate that ATF4 acts as a positive regulator in TLR4-triggered cytokine production.