MicroRNA-630 alleviates inflammatory reactions in rats with diabetic kidney disease by targeting toll-like receptor 4

BACKGROUND Diabetic kidney disease(DKD)is a major complication of diabetes mellitus.Renal tubular epithelial cell(TEC)damage,which is strongly associated with the inflammatory response and mesenchymal trans-differentiation,plays a significant role in DKD;However,the precise molecular mechanism is unknown.The recently identified microRNA-630(miR-630)has been hypothesized to be closely associated with cell migration,apoptosis,and autophagy.However,the association between miR-630 and DKD and the underlying mechanism remain unknown.AIM To investigate how miR-630 affects TEC injury and the inflammatory response in DKD rats.METHODS Streptozotocin was administered to six-week-old male rats to create a hypergly cemic diabetic model.In the second week of modeling,the rats were divided into control,DKD,negative control of lentivirus,and miR-630 overexpression groups.After 8 wk,urine and blood samples were collected for the kidney injury assays,and renal tissues were removed for further molecular assays.The target gene for miR-630 was predicted using bioinformatics,and the association between miR-630 and toll-like receptor 4(TLR4)was confirmed using in vitro investigations and double luciferase reporter gene assays.Overexpression of miR-630 in DKD rats led to changes in body weight,renal weight index,basic blood parameters and histopathological changes.RESULTS The expression level of miR-630 was reduced in the kidney tissue of rats with DKD(P<0.05).The miR-630 and TLR4 expressions in rat renal TECs(NRK-52E)were measured using quantitative reverse transcription polymerase chain reaction.The mRNA expression level of miR-630 was significantly lower in the high-glucose(HG)and HG+mimic negative control(NC)groups than in the normal glucose(NG)group(P<0.05).In contrast,the mRNA expression level of TLR4 was significantly higher in these groups(P<0.05).However,miR-630 mRNA expression increased and TLR4 mRNA expression significantly decreased in the HG+miR-630 mimic group than in the HG+mimic NC group(P<0.05).Furthermore,the levels of tumor necrosis factor-alpha(TNF-α),interleukin-1β(IL-1β),and IL-6 were significantly higher in the HG and HG+mimic NC groups than in NG group(P<0.05).However,the levels of these cytokines were significantly lower in the HG+miR-630 mimic group than in the HG+mimic NC group(P<0.05).Notably,changes in protein expression were observed.The HG and HG+mimic NC groups showed a significant decrease in E-cadherin protein expression,whereas TLR4,α-smooth muscle actin(SMA),and collagen IV protein expression increased(P<0.05).Conversely,the HG+miR-630 mimic group exhibited a significant increase in E-cadherin protein expression and a notable decrease in TLR4,α-SMA,and collagen IV protein expression than in the HG+mimic NC group(P<0.05).The miR-630 targets TLR4 gene expression.In vivo experiments demonstrated that DKD rats treated with miR-630 agomir exhibited significantly higher miR-630 mRNA expression than DKD rats injected with agomir NC.Additionally,rats treated with miR-630 agomir showed significant reductions in urinary albumin,blood glucose,TLR4,and proinflammatory markers(TNF-α,IL-1β,and IL-6)expression levels(P<0.05).Moreover,these rats exhibited fewer kidney lesions and reduced infiltration of inflammatory cells.CONCLUSION MiR-630 may inhibit the inflammatory reaction of DKD by targeting TLR4,and has a protective effect on DKD.

Toll-like receptors 2 polymorphism is associated with psoriasis: A case-control study in the northern Chinese population

Background:Psoriasis is a disease caused by genetics and immune system dysfunction,affecting the skin and joints.Toll-like receptors(TLRs)play an important role in triggering the innate immune response and controlling adaptive immunity.The role of TLR2 in the progression of psoriasis is not well understood.Methods:A case-control study was conducted on a northern Chinese Han population,consisting of psoriasis patients and healthy control subjects.Genotyping was performed using the tetra-primer amplification refractory mutation system-polymerase chain reaction(ARMS-PCR),and allele and genotype frequencies of four SNPs in TLR2 were analyzed in 270 psoriasis patients and 246 healthy controls.Results:Four TLR2 SNPs(rs11938228,rs4696480,rs3804099,rs5743699)were genotyped and found to be in linkage disequilibrium.The genotype distributions of rs11938228 and rs4696480 in two groups were in Hardy-Weinberg equilibrium and statistically significant except for the overdominance model.The haplotypes ATTC and ATCC were found to be protective against psoriasis.Conclusion:Our study found a correlation between TLR2 genetic variations and the likelihood of psoriasis in northern China.

The Role of Toll-Like Receptors and Nuclear Factor κB p65 Protein in the Pathogenesis of Otitis Media

The role of Toll-like receptor 4 (TLR4) and nuclear factor κB p65 (NF-κB p65) proteins in the pathogenesis of otitis media is explored. In recent years, the incidence of otitis media has been rising globally, becoming a significant threat to human health. More and more studies have found that Toll-like receptor 4 (TLR4), as a member of the Toll-like receptor family, can promote the generation of inflammatory factors and is closely related to the body’s immune response and inflammatory response. Nuclear factor-κB p65 (NF-κB p65) is a nuclear transcription factor that can interact with various cytokines, growth factors, and apoptotic factors, participating in processes such as oxidative stress, apoptosis, and inflammation in the body [1]. This article elaborates on the structure, function, and signaling pathways of TLR4 and NF-κB p65 proteins in the pathogenesis of otitis media, aiming to provide more precise targets and better therapeutic efficacy for the diagnosis and treatment of otitis media. The role of inflammation in disease.

Relationship of Toll-Like Receptors 2 and 4 Gene Polymorphisms with Essential Hypertension in Chinese Han Population

Objective: There are numerous studies suggesting that genetic polymor-phisms of inflammation factors Toll-like receptors 2 and 4 (TLR2, TLR4) might play a role in the pathophysiological process of hypertension. In this study, we evaluated the association in a sample of members of the Chinese Han population. Method: We selected four single nucleotide polymor-phisms (SNP) of TLR2 (rs3804099, rs3804100, rs7656411) and TLR4 (rs1927906) genes, and measured the distributions of genotypic and allelic frequencies in 1063 participants, including 391 essential hypertension pa-tients and 672 controls. Result: No significant differences in the genotypic and allelic frequencies of the four SNPs were detected between cases and controls. However, three haplotypes, CCG, TTG and TTT of TLR2, were significantly associated with a decrease in the risk of essential hyperten-sion (OR: 0.512, 95% CI: 0.397 - 0.660, P P = 0.0038;OR: 0.797, 95% CI: 0.667 - 0.952, P = 0.0122, respectively). Inversely, the risk of essential hypertension increased sig-nificantly in patients with the CTG, TCG or TCT haplotypes (OR: 2.924, 95% CI: 2.157 - 3.963, P P P Conclusion: Our study suggested that haplotypes (CCG, TTG, TTT, CTG, TCG and TCT) of TLR2 might have profound effects on the development of essential hypertension in the Chinese Han population.

METTL5 promotes cell proliferation,invasion,and migration by up-regulating Toll-like receptor 8 expression in colorectal cancer

BACKGROUND N6-methyladenosine(m6A)modification represents the predominant alteration found in eukaryotic messenger RNA and plays a crucial role in the progression of various tumors.However,despite its significance,the comprehensive investigation of METTL5,a key m6A methyltransferase,in colorectal cancer(CRC)remains limited.AIM To investigate the role of METTL5 in CRC.METHODS We assessed METTL5 expression levels in clinical samples obtained from CRC patients as well as in CRC cell lines.To elucidate the downstream targets of METTL5,we performed RNA-sequencing analysis coupled with correlation analysis,leading us to identify Toll-like receptor 8(TLR8)as a potential downstream target.In vitro functional assessments of METTL5 and TLR8 were conducted using CCK-8 assays,scratch assays,as well as assays measuring cell migration and invasion.RESULTS Our findings reveal a pronounced upregulation of METTL5 expression in both CRC cells and tissues,which correlated significantly with an unfavorable prognosis.In vitro experiments unequivocally demonstrated the oncogenic role of METTL5,as evidenced by its promotion of CRC cell proliferation,invasion,and migration.Notably,we identified TLR8 as a downstream target of METTL5,and subsequent down-regulation of TLR8 led to a significant inhibition of CRC cell proliferation,invasion,and tumor growth.CONCLUSION The heightened expression of METTL5 in CRC is strongly associated with clinicopathological features and a poor prognosis,thereby underscoring its potential utility as a critical marker for facilitating early diagnosis and prognostication in CRC.

On the Impairment of Stress-Induced Changes in Triglyceride Levels via a Sub-Toxic Dose of Unmethylated Cytidine Phosphate Guanosine Oligodinucleotide (a Toll-Like Receptor 9 Ligand)

Changes in lipid metabolism have been implicated in protection against infectious diseases. In the first experiment of this study, we measured clinical lipid parameters in a murine model where the unmethylated cytidine phosphate guanosine (CpG) oligodinucleotide (ODN1826), a Toll-like receptor 9 (TLR9) agonist was administered in combination with D-galactosamine (GalN) that caused relatively liver-specific inflammation and toxicity. In the control mice group injected with phosphate-buffered saline (PBS) (acute psychological stress model associated with blood sampling), the serum triglyceride (TG) levels showed a rapid decrease followed by a rebound at 24 h as we have recently reported. However, such a TG rebound was impaired in the CpG/GalN- and solely CpG-treated groups of mice despite an absence of liver injury based on serum alanine aminotransferase levels in the latter group. Thus, the stress-associated serum TG rebound was abrogated by the injection of a sub-hepatotoxic CpG dose. In the second experiment, we simply measured the hepatic CD36 and SACRB1 (the gene for scavenger receptor B1 (SR-B1)) transcripts after the i.p. administration of PBS, CpG or CpG/GalN. There was a remarkable elevation of hepatic CD36 transcript expression in both the CpG- and CpG/GalN-treated mice at 8 h post-CpG injection whereas the increase in the PBS-treated mice was slower than the former two groups, suggesting that hepatic CD36 transcript expression is more pronounced in the combined stress models than under psychological stress alone. The individual mice data showed that the increase in CD36 expression was accompanied by a reduction in SCARB1 mRNA, showing reciprocal regulation between these two genes. Together with our previously reported findings, these data suggest that, in a murine model combining psychological stress with TLR-triggered hepatic inflammation, the psychological stress facilitates liver uptake of plasma TG (and its components fatty acids), but the subsequent re-esterification and/or release of TG-rich lipoproteins from the liver is impaired due to the concomitant TLR-signaling. We hypothesize that lipid metabolism during acute stress shifts toward an elevated hepatic uptake of lipids due to concomitant TLR signaling, facilitating the clearance of bacterial lipids by the liver.

Influence of herb-partitioned moxibustion at Qihai (CV6) and bilateral Tianshu (ST25) and Shangjuxu (ST37) acupoints on toll-like receptors 4 signaling pathways in patients with ulcerative colitis

OBJECTIVE: To evaluate the efficacy of herb-partitioned moxibustion(HPM) at Qihai(CV6), Tianshu(ST25) and Shangjuxu(ST37) acupoints in relieving symptoms and the immune regulation of HPM on the toll-like receptors 4(TLR4) signaling pathway in ulcerative colitis(UC) patients.METHODS: A randomized, single-blind study was conducted 63 patients to receive HPM or sham HPM treatment. The efficacy outcomes included scores of the Mayo, Baron, inflammatory bowel disease questionnaire(IBDQ), self-rating depression scale(SDS), self-rating anxiety scale(SAS). HE staining was used to observe the histopathological changes of the colon. The expression of inflammatory cytokines and TLR4 signaling pathway related molecules were determined by enzyme-linked immunosorbent assay and immunohistochemistry.RESULTS: Baron, SDS, SAS scores were significantly decreased in moxibustion group(P < 0.05), IBDQ score was significantly greater in the moxibustion group than in the sham moxibustion group(P < 0.05). Histopathology of mucosal biopsies showed that both two groups improved in mucosa after treatment. The expression levels of tumor necrosis factor-α, interleukin-2, interleukin-12, interferon-γ, and TLR4, lipopolysaccharide, myeloid differentiation factor 88, interleukin receptor associated kinase, tumor necrosis factor receptor associated factor 6 and nuclear factor kappa-B p65 were significantly lower in the moxibustion group than in the sham moxibustion group(P < 0.05).CONCLUSION: This study showed that HPM at Qihai(CV6), Tianshu(ST25) and Shangjuxu(ST37) acupoints is effective to relieve symptoms, anxiety, depression and improving life quality in UC patients,which may be related to the immune regulation of HPM on TLR4 signaling pathway.

Fecal microbiota transplantation alleviates experimental colitis through the Toll-like receptor 4 signaling pathway

BACKGROUND Fecal microbiota transplantation(FMT)has shown promising therapeutic effects on mice with experimental colitis and patients with ulcerative colitis(UC).FMT modulates the Toll-like receptor 4(TLR4)signaling pathway to treat some other diseases.However,it remains unknown whether this modulation is also involved in the treatment of UC.AIM To clarify the necessity of TLR4 signaling pathway in FMT on dextran sodium sulphate(DSS)-induced mice and explain the mechanism of FMT on UC,through association analysis of gut microbiota with colon transcriptome in mice.METHODS A mouse colitis model was constructed with wild-type(WT)and TLR4-knockout(KO)mice.Fecal microbiota was transplanted by gavage.Colon inflammation severity was measured by disease activity index(DAI)scoring and hematoxylin and eosin staining.Gut microbiota structure was analyzed through 16S ribosomal RNA sequencing.Gene expression in the mouse colon was obtained by transcriptome sequencing.RESULTS The KO(DSS+Water)and KO(DSS+FMT)groups displayed indistinguishable body weight loss,colon length,DAI score,and histology score,which showed that FMT could not inhibit the disease in KO mice.In mice treated with FMT,the relative abundance of Akkermansia decreased,and Lactobacillus became dominant.In particular,compared with those in WT mice,the scores of DAI and colon histology were clearly decreased in the KO-DSS group.Microbiota structure showed a significant difference between KO and WT mice.Akkermansia were the dominant genus in healthy KO mice.The ineffectiveness of FMT in KO mice was related to the decreased abundance of Akkermansia.Gene Ontology enrichment analysis showed that differentially expressed genes between each group were mainly involved in cytoplasmic translation and cellular response to DNA damage stimulus.The top nine genes correlating with Akkermansia included Aqp4,Clca4a,Dpm3,Fau,Mcrip1,Meis3,Nupr1 L,Pank3,and Rps13(|R|>0.9,P<0.01).CONCLUSION FMT may ameliorate DSS-induced colitis by regulating the TLR4 signaling pathway.TLR4 modulates the composition of gut microbiota and the expression of related genes to ameliorate colitis and maintain the stability of the intestinal environment.Akkermansia bear great therapeutic potential for colitis.

Divergent expression of bacterial wall sensing toll-like receptors 2 and 4 in colorectal cancer

To characterize the expression of toll-like receptors (TLR) 2 and 4 in colorectal cancer (CRC) and in normal colorectal mucosa. METHODSWe analysed tissue samples from a prospective series of 118 unselected surgically treated patients with CRC. Sections from formalin fixed, paraffin embedded specimens were analysed for TLR2 and TLR4 expression by immunohistochemistry. Two independent assessors evaluated separately expression at the normal mucosa, at the invasive front and the bulk of the carcinoma, and in the lymph node metastases when present. Expression levels in different locations were compared and their associations with clinicopathological features including TNM-stage and the grade of the tumour and 5-year follow-up observations were analysed. RESULTSNormal colorectal epithelium showed a gradient of expression of both TLR2 and TLR4 with low levels in the crypt bases and high levels in the surface. In CRC, expression of both TLRs was present in all cases and in the major proportion of tumour cells. Compared to normal epithelium, TLR4 expression was significantly weaker but TLR2 expression stronger in carcinoma cells. Weak TLR4 expression in the invasive front was associated with distant metastases and worse cancer-specific survival at 5 years. In tumours of the proximal colon the cancer-specific survival at 5 years was 36.9% better with strong TLR4 expression as compared with those with weak expression (P = 0.044). In contrast, TLR2 expression levels were not associated with prognosis. Tumour cells in the lymph node metastases showed higher TLR4 expression and lower TLR2 expression than cells in primary tumours. CONCLUSIONTumour cells in CRC show downregulation of TLR4 and upregulation of TLR2. Low expression of TLR4 in the invasive front predicts poor prognosis and metastatic disease.

Expression and Implication of Toll-like Receptors TLR2,TLR4 and TLR9 in Colonic Mucosa of Patients with Ulcerative Colitis

Toll-like receptors （TLRs） family may play important roles in inflammatory bowel dis- ease. This study examined the expression of TLR2, TLR4 and TLR9 in the colonic tissues of patients with ulcerative colitis 0AC） and explored their roles in the pathogenesis of UC. Colonic biQpsies were taken from the colon of 30 patients with mild or moderate UC （at active phase） and 10 healthy con- trois during colonoscopy. TLR2, TLR4 and TLR9 protein expression levels were immunohisto- chemically detected. The mRNA expression levels of TLR2, TLR4 and TLR9 were assessed by re- verse transcription polymerase chain reaction （RT-PCR）. The disease activity index （DAI）, colono- scopic and histologic grades and fecal microbial flora were determined. Histological examination showed that the intestinal mucous membrane of UC patients underwent acute inflammation changes. Immunohistochemistry exhibited that the expression levels of TLR2, TLR4 and TLR9 in colon epi- thelia and inflammatory cells were higher in UC patients than in control group （P〈0.01）. The mRNA expression levels of TLR2, TLR4 and TLR9 were increased in UC patients but were not detected in the normal controls. Expression levels ofTLR2, TLR4 and TLR9 were positively correlated, and bore close correlation with DAI, colonoscopic and histologic grades and fecal microbial flora. An impor- tant mechanism of UC might be that abnormal activation of mucosal immunity by intestinal dysbac- teriosis caused dysregulation of TLRS that mediates innate immunity.

Argon preconditioning protects neuronal cells with a Toll-like receptor-mediated effect

The noble gas argon has the potential to protect neuronal cells from cell death.So far,this effect has been studied in treatment after acute damage.Preconditioning using argon has not yet been investigated.In this study,human neuroblastoma SH-SY5Y cells were treated with different concentrations of argon(25%,50%,and 74%;21%O_(2),5%CO_(2),balance nitrogen)at different time intervals before inflicting damage with rotenone(20μM,4 hours).Apoptosis was determined by flow cytometry after annexin V and propidium iodide staining.Surface expressions of Toll-like receptors 2 and 4 were also examined.Cells were also processed for analysis by western blot and qPCR to determine the expression of apoptotic and inflammatory proteins,such as extracellular-signal regulated kinase(ERK1/2),nuclear transcription factor-κB(NF-κB),protein kinase B(Akt),caspase-3,Bax,Bcl-2,interleukin-8,and heat shock proteins.Immunohistochemical staining was performed for TLR2 and 4 and interleukin-8.Cells were also pretreated with OxPAPC,an antagonist of TLR2 and 4 to elucidate the molecular mechanism.Results showed that argon preconditioning before rotenone application caused a dose-dependent but not a time-dependent reduction in the number of apoptotic cells.Preconditioning with 74%argon for 2 hours was used for further experiments showing the most promising results.Argon decreased the surface expression of TLR2 and 4,whereas OxPAPC treatment partially abolished the protective effect of argon.Argon increased phosphorylation of ERK1/2 but decreased NF-κB and Akt.Preconditioning inhibited mitochondrial apoptosis and the heat shock response.Argon also suppressed the expression of the pro-inflammatory cytokine interleukin-8.Immunohistochemistry confirmed the alteration of TLRs and interleukin-8.OxPAPC reversed the argon effect on ERK1/2,Bax,Bcl-2,caspase-3,and interleukin-8 expression,but not on NF-κB and the heat shock proteins.Taken together,argon preconditioning protects against apoptosis of neuronal cells and mediates its action via Toll-like receptors.Argon may represent a promising therapeutic alternative in various clinical settings,such as the treatment of stroke.

Correlation between Toll-like Receptor Gene Polymorphisms and Idiopathic Nephrotic Syndrome in Chinese Children

Objective Idiopathic nephrotic syndrome(INS)is the most common glomerular disease in children.Toll-like receptors(TLRs)have been reported to be associated with response to steroid treatment in children with INS.Nevertheless,the correlation between TLR genes and the progression of INS has not yet been clarified.The present study aimed to investigate the association of single-nucleotide polymorphisms(SNPs)in TLR2,TLR4,and TLR9 with susceptibility to INS as well as the clinical phenotyping of steroid responsiveness in Chinese children with INS.Methods A total of 183 pediatric inpatients with INS were included and given standard steroid therapy.Based on their clinical response to steroids,the patients were classified into three groups:steroid-sensitive nephrotic syndrome(SSNS),steroid-dependent nephrotic syndrome(SDNS),and steroid-resistant nephrotic syndrome(SRNS).A total of 100 healthy children were employed as controls.The blood genome DNA was extracted from each participant.Six SNPs(rs11536889,rs1927914,rs7869402,rs11536891,rs352140,and rs3804099)in TLR2,TLR4,and TLR9 were selected and detected by multiplex polymerase chain reaction with next-generation sequencing to assess TLR gene polymorphisms.Results Among the 183 patients with INS,89(48.6%)had SSNS,73(39.9%)had SDNS,and 21(11.5%)had SRNS.No significant difference was found in the genotype distribution between healthy children and patients with INS.However,the genotype and allele frequencies of TLR4 rs7869402 were significantly different between SRNS and SSNS.Compared with patients with the C allele and CC genotype,patients with the T allele and CT genotype had an increased risk of SRNS.Conclusion TLR4 rs7869402 affected the steroid response in Chinese children with INS.It might be a predictor for the early detection of SRNS in this population.

Betaine inhibits Toll-like receptor 4 expression in rats with ethanol-induced liver injury

AIM:To test whether ethanol feeding could induce Toll-like receptor 4(TLR4)responses,assess the hepatoprotective effect of betaine and its inhibitive effect on TLR4 in animal models of alcoholic liver injury.METHODS:Forty-eight female Sprague-Dawley rats were randomly divided into four groups as control,model,low and high dose betaine groups.Except control group,all rats were fed with high fat-containing diet plus ethanol and fish oil gavages for 8 wk.Betaine was administered intragastrically after exposure of ethanol for 4 wk.The changes of liver histology were examined.The expression of TLR4 mRNA and protein was detected by RT-PCR and Western blotting,respectively.The serum aminotransferase activity alanine transarninase(ALT),aspartate aminotransferase(AST),serum endotoxin,and liver inflammatory factors tumor necrosis factor-α(TNF-α),interferon-γ(IFN-γ),interleukin-18(IL-18)were also assayed.RESULTS:Compared with control group,rats of model group developed marked liver injury,accompanied by an increase of ALT(159.41±7.74 U/L vs 59.47± 2.34 U/L,P<0.0001),AST(248.25±1.40 U/L vs 116.89±3.48 U/L,P<0.0001),endotoxin(135.37± 30.17 ng/L vs 44.15±7.54 ng/L,P<0.0001),TNF-α(20.81±8.58 pg/mL vs 9.34±2.57 pg/mL,P=0.0003),IFN-γ(30.18±7.60 pg/mL vs 16.86±9.49 pg/mL,P= 0.0039)and IL-18(40.99±8.25 pg/mL vs 19.73±9.31 pg/mL,P=0.0001).At the same time,the expression of TLR4 mRNA and protein was markedly induced in the liver after chronic ethanol consumption(1.45±0.07 vs 0.44±0.04,P<0.0001;1.83±0.13 vs 0.56±0.08,P<0.0001).Compared with model group,betaine feeding resulted in significant decreases of ALT(64.93 ±6.06 U/L vs 159.41±7.74 U/L,P<0.0001),AST(188.73±1.11 U/L vs 248.25±1.40 U/L,P<0.0001),endotoxin(61.80±12.56 ng/L vs 135.37±30.17 ng/L,P<0.0001),TNF-α(9.79±1.32 pg/mL vs 20.81± 8.58 pg/mL,P=0.0003),IFN-γ(18.02±5.96 pg/mL vs 30.18±7.60 pg/mL,P=0.0008)and IL-18(18.23±7.01 pg/mL vs 40.99±8.25 pg/mL,P<0.0001).Betaine also improved liver steatosis.The expression levels of TLR4 mRNA or protein in liver tissues were significantly lowered(0.62±0.04 vs 1.45±0.07,P<0.0001;and 0.65±0.06 vs 1.83±0.13,P<0.0001).There was a statistical difference of TLR4 mRNA and protein expression between high-and low-dose betaine groups(0.62±0.04 vs 0.73±0.05,P<0.0001,and 0.65±0.06 vs 0.81±0.09,P<0.0001).CONCLUSION:Betaine can prevent the alcoholinduced liver injury effectively and improve the liver function.The expression of TLR4 increases significantly in ethanol-fed rats and betaine administration can inhibit TLR4 expression.

Association between polymorphisms in the Toll-like receptor 4,CD14,and CARD15/NOD2and inflammatory bowel disease in the Greek population

AIM: Crohn's disease(CD)and ulcerative colitis(UC)are multifactorial diseases with a significant genetic background.Apart from CARD15/NOD2 gene, evidence is accumulating that molecules related to the innate immune response such as CD14 or Toll-like receptor 4 (TLR4), are involved in their pathogenesis. In further exploring the genetic background of these diseases, we investigated the variations in the CARD15/NOD2 gene (Arg702Trp,Gly908Arg and Leu1007fsinsC), and polymorphisms in the TLR4 gene (Asp299Gly and Thr399Ile) as well as in the promoter of the CD14 gene (T/C at position -159) in Greek patients with CD and UC.METHODS: DNA was obtained from 120 patients with CD,85 with UC and 100 healthy individuals. Genotyping was performed by allele specific PCR or by PCR-RFLP analysis.RESULTS: The 299Gly allele frequency of the TLR4 gene and the T allele and TT genotype frequendes of the CD14 promoter were significantly higher in CD patients only compared to healthy individuals (P = 0.026＜0.05; P = 0.0048＜0.01 and P= 0.047＜0.05 respectively). Concerning the NOD2/CARD15mutations the overall presence in CD patients was significantly higher than that in UC patients or in controls.Additionally, 51.67% of the CD patients were carriers of a TLR4 and/or CD14 polymorphic allele and at least one variant of the NOD2/CARD15, compared to 27% of the UC patients. It should be pointed out that both frequencies significantly increased as compared with the 10% frequency of multiple carriers found in healthy controls. A possible interaction of the NOD2/CARD15 with TLR4 and especially CD14, increased the risk of developing inflammatory bowel disease (IBD).CONCLUSION: Our results indicate that co-existence of a mutation in either the TLR4 or CD14 gene, and in NOD2/CARD15is associated with an increased susceptibility to developing CD compared to UC, and to developing either CD or UC compared to healthy individuals.

Effects of ω-3 fatty acids on toll-like receptor 4 and nuclear factor-κB p56 in lungs of rats with severe acute pancreatitis

AIM To determine the effects of ω-3 fatty acids(ω-3FA) on the toll-like receptor 4(TLR4)/nuclear factor κB p56(NF-κBp56) signal pathway in the lungs of rats with severe acute pancreatitis(SAP).METHODS A total of 56 Sprague-Dawley rats were randomly divided into 4 groups: control group, SAP-saline group, SAP-soybean oil group and SAP-ω-3FA group. SAP was induced by the retrograde infusion of sodium taurocholate into the pancreatic duct. The expression of TLR4 and NF-κBp56 in the lungs was evaluated by immunohistochemistry and Western blot analysis. The levels of inflammatory cytokines interleukin-6 and tumor necrosis factor-alpha in the lungs were measured by enzyme-linked immunosorbent assay. RESULTS The expression of TLR4 and NF-κBp56 in lungs and of inflammatory cytokines in serum significantly increased in the SAP group compared with the control group(P < 0.05), but was significantly decreased in the ω-3FA group compared with the soybean oil group at 12 and 24 h(P < 0.05).CONCLUSION During the initial stage of SAP, ω-3FA can efficiently lower the inflammatory response and reduce lung injury by triggering the TLR4/NF-κBp56 signal pathway.

Lactobacilli inhibit interleukin-8 production induced by Helicobacter pylori lipopolysaccharide-activated Toll-like receptor 4

AIM： To investigate the effect of Lactobacillus bulgaricus （LBG） on the Toll-like receptor 4 （TLR4） pathway and interleukin-8 （IL-8） production in SGC-7901 cells treated with Helicobacter pyloriSydney strain 1 lipopolysaccharide （HpyloriSS1-LPS）. METHODS： SGC-7901 cells were treated with HpyloriSS1-LPS in the presence or absence of pretreatment for 1 h with viable LBG or supernatant recovered from LBG culture MRS broth （LBG-s）. Cellular lysates were prepared for Western blot with anti-TLR4, anti-transforming growth factor β-activated kinase 1 （TAK1）, anti-phospho-TAK1, anti-nuclear factor κB （NF-κB）, anti-p38 mitogen-activated protein kinase （p38MAPK）, and anti-phospho-p38MAPK antibodies. The amount of IL-8 in cell culture medium was measured by ELISA. RESULTS： H pyloriSS1-LPS up-regulated the expression of TLR4, stimulated the phosphorylation of TAKI, subsequently enhanced the activation of NF- κB and the phosphorylation of p38MAPK in a time- dependent manner, leading to augmentation of IL-8 production in SGC-7901 cells. Viable LBG or LBG-s pretreatment attenuated the expression of TLR4, inhibited the phosphorylation of TAK1 and p38MAPK, prevented the activation of NF-κB, and consequently blocked IL-8 production.CONCLUSION： H py/oriSS1-LPS induces IL-8 production through activating TLR4 signaling in SGC-7901 cells and viable LBG or LBG-s prevents H pyloriSS1-LPS-mediated IL-8 production via inhibition of the TLR4 pathway.

Association of Toll-like receptor 4 Signaling Pathway with Steroid-induced Femoral Head Osteonecrosis in Rats

Osteonecrosis of the femoral head is frequently observed in patients treated with excessive corticosteroids. However, the pathogenesis of corticosteroid-induced osteonecrosis remains unclear. The purpose of this study was to investigate the role of Toil-like receptor 4 （TLR4） signaling pathway in steroid-induced femoral head osteonecrosis in rats. Male Sprague-Dawley rats were injected intramus- cularly with 20 mg/kg methylprednisolone （MP） for 8 weeks, twice per week. The animals were sacri- ficed at 2, 4 and 8 weeks after the last MP injection, respectively, and then allocated to the 2-, 4- and 8-week model groups （n=24 each）. Rats in the control group （n=12） were not given any treatment. Histopathological analysis was performed and the concentration of tartrate-resistant acid phosphatase （TRAP） in plasma was determined. The activation of osteoclasts in the femoral head was assessed by TRAP staining. The expression of TLR4, MyD88, TRAF6 and NF-Id3 p65 that are involved in TLR4 signaling, and MCP-1 production were detected by using real-time PCR （RT-PCR） and Western blotting. The results showed that the osteonecrosis in the femoral head was clearly observed and the concentra- tion of TRAP in the plasma was increased in the model rats. The femoral head tissues in MP-treated rats were positive for TRAP and the intensity of TRAP staining was greater in MP-treated rats than in con- trol rats. As compared with the control group, the mRNA expression of TLR4 signaling-related factors was enhanced significantly at 4 and 8 weeks, and the protein levels of these factors increased signifi- cantly with time. It was concluded that MP could induce the femoral head osteonecrosis in rats, which was associated with osteoclast activation via the TLR4 signaling pathway. These findings suggest that TLR4 signaling pathway plays a pivotal role in the pathogenesis of steroid-induced osteonecrosis.

Clinical significance of NOD2/CARD15 and Toll-like receptor 4 gene single nucleotide polymorphisms in inflammatory bowel disease

AIM： To evaluate the role of genetic factors in the pathogenesis of Crohn＇s disease （CD） and ulcerative colitis （UC）, we investigated the single nucleotide polymorphisms （SNPs） of NOD2/CARD15 （R702W, Gg08R and L1007finsC）, and Toll-like receptor 4 （TLR4） genes （D299G and T399I） in a selected inflammatory bowel disease （IBD） population coming from Southern Italy. METHODS： Allele and genotype frequencies of NOD2/ CARD15 （R702W, Gg08R and L1007finsC） and TLR4 （D299G and T399I） SNPs were examined in 133 CD patients, in 45 UC patients, and in 103 healthy controls. A genotype-phenotype correlation was performed. RESULTS： NOD2/CARD15 R702W mutation was significantly more frequent in CD （9.8%） than in controls （2.4%, P = 0.001） and in UC （2.3%, P = 0.03）. No significant difference was found between UC patients and control group （P 〉 0.05）. In CD and UC patients, no significant association with G908R variant was found. L1007finsC SNP showed an association with CD （9.8%） compared with controls （2.9%, P = 0.002） and UC patients （2.3%, P = 0.01）. Moreover, in CD patients, G908R and L1007finsC mutations were significantly associated with different phenotypes compared to CD wild-type patients. No association of IBD with the TLR4 SNPs was found in either cohort （allele frequencies： D299G-controls 3.9%, CD 3.7%, UC 3.4%, P 〉 0.05; T399I-controls 2.9%, CD 3.0%, UC 3.4%, P 〉 0.05）. CONCLUSION： These findings confirm that, in our IBD patients selected from Southern Italy, the NOD2/ CARD15, but not TLR4 SNPs, are associated with increased risk of CD.

Impact of Probiotics on Toll-like Receptor 4 Expression in an Experimental Model of Ulcerative Colitis

Toll-like receptors （TLRs） are key components of the innate immune system which trigger antimicrobial host defense responses. This study aimed to investigate the impact of probiotics （Lactoba- cillus, Bifiidobacterium） on the expression of TLR4 and tumor necrosis factor-alpha （TNF-α in the co- lon mucosa of rat experimental ulcerative colitis model induced by trinitrobenzene sulfonic acid （TNBS）/ethanol and immune complexes. The gross and histological changes of the colonic mucosa were observed and assessed by the means-standard deviation and independent samples t-test. The pro- tein expression levels of TLR4 and TNF-α were detected by using immunohistochemistry and Westem blotting, respectively. It was revealed that there was visible infiltration of inflammatory cells, formation of crypt abscess, and the reduction of goblet cells in the colon tissue of experimental models. As com- pared with the control group, the levels of TLR4 and TNF-α protein were significantly increased in the model group （P〈0.01 for both）. No significant difference was found in the expression of TLR4 and TNF-α between the two-week probiotics treatment group and the model group （P〉0.05）, whereas sig- nificant reductions were shown in rats which were treated with probiotics for four weeks as compared with the model group （P〈0.01）. There was no significant difference between two probiotics-treated groups. Our results implied that probiotics were likely to play a key role in protecting ulcerative colitis by reducing the inflammatory factor TNF-α expression through inhibiting the TLR4 expression in the colon tissue of experimental models.

Production of interleukin-1β related to mammalian target of rapamycin/Toll-like receptor 4 signaling pathway during Aspergillus fumigatus infection of the mouse cornea

AIM：To elucidate the effect of rapamycin on regulating the production of interleukin（IL）-1β in Aspergillus fumigatus（A.fumigatus）-induced keratitis and to verify whether the expression of IL-1β in A.fumigatus keratitis is associated with the mammalian target of rapamycin（mT OR）/Toll-like receptor 4（TLR4） signaling pathway.METHODS：Fungal keratitis mouse models of susceptible C57 BL/6 mice were established using A.fumigatus.The mice were subsequently treated with rapamycin.The protein levels of p-mT OR,TLR4,and IL-1β in normal and infected corneal tissue were measured by Western blot.The TLR4 and IL-1β m RNA levels were determined by real-time polymerase chain reaction（PCR）.RESULTS：In C57 BL/6 mice,rapamycin treatment decreased the clinical scores and production of the pro-inflammatory cytokine,IL-1β.The expression of TLR4,stimulated by A.fumigatus,was reduced as well when the mT OR signaling pathway was suppressed by rapamycin.CONCLUSION：Rapamycin is beneficial for the outcome of fungal keratitis and has an inhibitory effect expression of the inflammatory cytokine IL-1β.The inhibitory effect on IL-1β expression can be associated with the mT OR/TLR4 signaling pathway in A.fumigatus infection in mice.