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.

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.

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.

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.

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.

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.

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.

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.

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.

Effect of Ligands to Toll-Like Receptors (TLR) 3, 7 and 9 on Mice Infected with Mouse Hepatitis Virus A59

Mice infected with mouse hepatitis virus A59 (MHV-A59), an enveloped, positive-strand RNA Co-ronavirus, induce hepatitis, thymus involution, IgG2a-restricted hypergammaglobulinaemia, transaminase release and autoantibodies (autoAb) to liver and kidney fumarylacetoacetate hy-drolase (FAH). Since Toll-like receptors (TLR) play a central role in innate immunity, we explored the effects of TLR3, 7 and 9 stimulation on MHV mouse infection. Thus, the animals were treated with Poly (I:C), Loxoribine and CpG, the respective TLR ligands. MHV-infected mice inoculated with Poly (I:C) had significant lower levels of plasma transaminases and Ig, anti-MHV Ab, and uric acid than MHV-infected animals, whereas autoAb to kidney tissue were observed. Loxoribine only produced a slight decrease of uric acid levels and serum Ig. CpG showed deleterious effects on MHV-infected mice, since survival of animals dramatically dropped to about 10%. AutoAb to murine tissues and uric acid release were not affected, whereas transaminases and anti-MHV Ab were slightly elevated. Besides, CpG administration produced a decrease of the high levels of serum Ig induced by the virus. Therefore, results indicated that TLR3 stimulation appeared to protect the animals against the viral infection, whereas CpG aggravated its signs. Loxoribine, the TLR7 ligand, did not show major effects.

Molecular Assessment of Non-Muscle Invasive and Muscle Invasive Bladder Tumors: Mapping of Putative Urothelial Stem Cells and Toll-Like Receptors (TLR) Signaling

Purpose: The main objectives of this study were to characterize and compare the urothelial stem cells (healthy and cancer cells) and TLRs features in the urinary bladder of men without lesionsand with non-muscle-invasive and muscle invasive urothelial tumors. Materials and Methods: Thirty samples of the urinary bladder of 50 to 80-year-old men, with and without diagnosis of malignant urothelial lesions were used. The 30 samples were divided into 3 groups (n = 10 per group): Normal Group;Non-Muscle Invasive Bladder Cancer Group;Muscle Invasive Bladder Cancer Group. The samples were histopathologically and immunohistochemically analyzed. The study was conducted at teaching Hospital of the University of Campinas (UNICAMP). Results: The CD44 and CD133 immunoreactivities were significantly intense in the muscle-invasive cancer group when compared to the other groups. The ABCG2 biomarker demonstrated intense immunoreactivities in both non-muscle and muscle invasive groups, and absent immunoreactivity in the normal group. All groups showed weak CD117 immunoreactivity. Putative Healthy Stem Cells (CD44/CD133/ CD117+) occurred in all groups. Putative Cancer Stem Cells (CD44/CD133/ABCG2+) only occurred in the non-muscle and muscle invasive cancer groups. TLR2 immunoreactivity was significantly lower in the non-muscle invasive cancer group and absent in the muscle invasive cancer group. TLR4 immunoreactivity was significantly lower in both cancer groups. Conclusions: This study leads us to the conclusion that putative cancer stem cell occurrence was sensitive to the decreased in TLR2 and TLR4 immunoreactivities. Also, TLR2 and TLR4 demonstrated their involvement in the regulation of the different biomarkers for putative healthy and cancer urothelial stem cells, probably acting as negative regulators of urothelial carcinogenesis. Taken together data obtained suggest that use of TLRs agonists could be a promising alternative for the treatment of non-muscle and muscle invasive bladder tumors.

人Toll-like receptor 2胞外段的克隆和表达

目的 克隆、表达人Toll-like receptor2(TLR2)胞外段(A26-T588)基因,获得人TLR2胞外段蛋白。方法 RT-PCR扩增TLR2胞外段基因,以pcDNA3.1+质粒为载体在HEK293细胞中表达TLR2胞外段蛋白,同时以pcDNA3.1+/TLR2(A26-T588)重组质粒免疫昆明鼠,制备抗TLR2胞外段蛋白多抗。结果 PCR扩增及重组质粒测序结果表明成功地构建了pcDNA3.1+/TLR2(A26-T588)真核表达质粒,SDS-PAGE分析纯化产物在M_r为68000处出现明显蛋白条带。重组质粒DNA免疫小鼠3次后,血清抗体滴度可达1∶250。TLR2胞外段蛋白可与LPS结合,并在一定的质量浓度范围内呈剂量依赖性。结论 构建的pcDNA3.1+/TLR2(A26-T588)真核表达质粒可在哺乳动物细胞中表达TLR2胞外段蛋白,并与重组质粒DNA免疫小鼠抗血清及TLR2单克隆抗体TL2.1特异性反应,由此证明其表达正确。

广谱模式识别分子Toll-like receptor 2的研究进展

TLR-2（Toll-like receptor 2,TLR-2）是哺乳动物TLRs（Toll-like receptors,TLRs）家族的一员,作为细胞表面的天然受体蛋白,主要参与病原微生物产物的识别及炎症信号传导,介导天然抗感染兔疫;最近又发现其参与机体对非感染因子所致炎性组织损伤的识别。通过对TLR-2参与的识别和细胞内信号传导机制的研究,可为深入探讨抵御微生物感染的机制、对自身正常与非正常组织的识别提供新的思路。

Toll-like Receptor9在大鼠胰腺表达及与大鼠急性胰腺炎相关性的研究

目的 (1)建立急性胰腺炎大鼠模型,定性检测Toll-like Receptor 9(TLR 9)在大鼠胰腺的表达、分布情况;(2)定量测定TLR 9在大鼠急性胰腺炎不同时间点的表达变化情况;(3)结合TLR 9在大鼠胰腺的组织分布、表达情况及在雨蛙素诱导性胰腺炎(cerulein-induced pancreatitis,CIP)早期24 h的表达改变,探讨TLR9与CIP发生发展的相关性.方法(1)采用Wistar大鼠,并随机分配进入实验组或对照组;通过皮下注射雨蛙素建立急性胰腺炎模型;(2)采用免疫组化方法检测TLR 9在正常大鼠胰腺及CIP时大鼠胰腺的表达TLR 9在大鼠胰腺的组织分布情况;(3)提取总RNA,采用实时荧光定量逆转录-多聚酶链反应(Quantitative-Real-Time;QRT-PCR)法测定TLR9基因的表达.(4)分析TLR9的分布特征及可能的意义(5)统计分析TLR 9 mRNA的表达情况与CIP发生、发展的关系.结果 (1)TLR 9主要分布于胰管上皮、血管内皮和胰岛;(2)外分泌腺泡细胞没有明显的表达;(3)QRT-PCR结果显示TLR9 mRNA在正常大鼠胰腺组织呈现低水平表达;(4)CIP早期TLR9 mRNA表达出现快速上调并在1 h时达到最高值;TLR 9 mRNA表达在CIP前4 h内维持于高水平;其后下降缓慢,至到CIP的第24小时也未降至正常,保持相对较高的表达水平.结论 (1)TLR 9在大鼠胰腺有表达,且表达具有一定的组织特异性;(2)TLR9在CIP胰腺组织中的表达明显升高,提示TLR 9在胰腺炎早期炎症反应的发生、发展中具有重要作用,与之存在相关性.

Toll-like receptor 2及其信号传导通路在阿片类物质诱导细胞凋亡中的作用

目的:成瘾物质(Addictive drugs)导致的中毒性脑病的中枢神经系统损害以神经元凋亡为突出表现,具体机制仍有待进一步的研究探讨。方法:Toll-like receptor 2(TLR2)不仅是激活机体自身免疫防御和炎症反应的重要受体,而且广泛参与多种细胞功能,包括细胞凋亡。我们使用体外培养的HEK293和高表达TLR2的HEK2932种细胞,以及体外培养小鼠皮层原代神经元细胞,研究经过吗啡处理后细胞存活率和凋亡的变化,以探讨TLR2信号通路在吗啡诱导的细胞凋亡中的作用。结果:TLR2高表达导致吗啡诱导的细胞存活率下降和细胞凋亡的显著增加。使用MyD88抑制体竞争性抑制MyD88并阻断TLR2信号通路后,吗啡诱导的TLR2高表达细胞的凋亡也被明显抑制。长期的吗啡处理导致正常神经元的TLR2在信使RNA(mRNA)水平和蛋白水平表达明显增高,而且在TLR2功能缺失的原代神经元细胞中,吗啡诱导的caspase-3活性增高被阻断,吗啡诱导的神经元凋亡也被明显抑制。结论:TLR2信号通路参与吗啡诱导的神经元凋亡。

Science Letters:A synthetic Toll-like receptor 2 ligand decreases allergic immune responses in a mouse rhinitis model sensitized to mite allergen

It has been proposed that activation of Toll-like receptors （TLRs） plays crucial roles in the polarization of adaptive immune responses. A synthetic Toll-like receptor 2 （TLR2） ligand, Pam3CSK4, has been reported to modulate the balance of Th1/Th2 responses. We evaluated the modulation effect of Pam3CSK4 on allergic immune response in a mouse rhinitis model sensitized to house dust mite allergen （HDM）. Mice were sensitized and challenged with Dermatophagoidesfarinae allergen （Der f）, and then the allergic mice were treated by Pam3CSK4. Nasal allergic symptoms and eosinophils were scored. Der f-specific cytokine responses were examined in the splenocytes and bronchoalveolar lavage fluid （BALF）. Serum level of total IgE was also detected. After establishing a mouse allergic rhinitis model with HDM, we have showed that Pam3CSK4 treatment not only ameliorated the nasal allergic symptoms remarkably but also decreased the eosinophils and total inflammation cells in BALF significantly. Analysis of cytokine profile found that IFN-7 released from either BALF or stimulated splenocytes increased markedly in Pam3CSK4-treated mice, while IL-13 decreased significantly. Moreover, serum level of total IgE was significantly lower in Pam3CSK4-treated mice than in the untreated. Thus, in an allergic rhinitis mouse model developed with HDM, Pam3CSK4 was shown to exhibit an antiallergic effect, indicating its potential application in allergic diseases.

Activation of Toll-like receptors signaling in non-small cell lung cancer cell line induced by tumor-associated macrophages

Background： Inflammation is often linked with the progress and poor outcome of lung cancer. The understanding of the relationship between tumor-associated macrophages （TAMs） and lung cancer cells involves in the underlying mechanism of inflammatory cytokine production. Toll-like receptors （TLRs） are engaged in promoting the production of pro-inflammatory cytokines and play an important role in tumor immunology. Methods： To investigate the mechanisms by which TAMs influence the production of pro-inflammatory cytoldnes in lung cancer cells, we established an in vitro coculture system using TAMs and human non- small cell lung cancer （NSCLC） cell line SPC-A1. Levels of interleukin （IL）-113, IL-6 and IL-8 in SPC-A1 were evaluated by RT-PCR and cytometric bead array assay after being cocultured with TAMs. Expression changes of TLRs and TLRs signaling pathway proteins in SPC-Al were further confirmed by RT-PCR and western blot. The level changes of IL-1β, IL-6 and IL-8 in SPC-Al were also detected after the stimulation of TLRs agonists. Results： We found that the phenotype markers of TAMs were highly expressed after stimulating human monocyte cell line THP-1 by phorbol-12-myristate-β-acetate （PMA）. Higher mRNA and supernate secretion levels of IL-1β, IL-6 and IL-8 were detected in SPC-A1 after being eocultured with TAMs. We also found that TLR1, TLR6 and TLR7 were up-regulated in SPC-A1 in the coculture system with TAMs. Meanwhile, TLRs signaling pathway proteins were also significantly activated. Moreover, pre-treatment with agonist ligands for TLR1, TLR6 and TLR7 could dramatically promote inductions of IL-1β, IL-6 and IL-8. Conclusions： These findings demonstrated that TAMs may enhance IL-1β, IL-6 and IL-8 expressions via TLRs signaling pathway. We conclude that TAMs contribute to maintain the inflammation microenvironment and ultimately promote the development and progression of lung cancer.

Role of gut microbiota and Toll-like receptors in nonalcoholic fatty liver disease

Emerging data have shown a close association between compositional changes in gut microbiota and the development of nonalcoholic fatty liver disease(NAFLD).The change in gut microbiota may alter nutritional absorption and storage.In addition,gut microbiota are a source of Toll-like receptor(TLR)ligands,and their compositional change can also increase the amount of TLR ligands delivered to the liver.TLR ligands can stimulate liver cells to produce proinflammatory cytokines.Therefore,the gut-liver axis has attracted much interest,particularly regarding the pathogenesis of NAFLD.The abundance of the major gut microbiota,including Firmicutes and Bacteroidetes,has been considered a potential underlying mechanism of obesity and NAFLD,but the role of these microbiota in NAFLD remains unknown.Several reports have demonstrated that certain gut microbiota are associated with the development of obesity and NAFLD.For instance,a decrease in Akkermansia muciniphila causes a thinner intestinal mucus layer and promotes gut permeability,which allows the leakage of bacterial components.Interventions to increase Akkermansia muciniphila improve the metabolic parameters in obesity and NAFLD.In children,the levels of Escherichia were significantly increased in nonalcoholic steatohepatitis(NASH)compared with those in obese control.Escherichia can produce ethanol,which promotes gut permeability.Thus,normalization of gut microbiota using probiotics or prebiotics is a promising treatment option for NAFLD.In addition,TLR signaling in the liver is activated,and its downstream molecules,such as proinflammatory cytokines,are increased in NAFLD.To data,TLR2,TLR4,TLR5,and TLR9 have been shown to be associated with the pathogenesis of NAFLD.Therefore,gut microbiota and TLRs are targets for NAFLD treatment.

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.