Effects of butyphthalide on microglia polarization after intracerebral hemorrhage and the underlying mechanisms / 中南大学学报(医学版)

OBJECTIVES@#Because intracerebral hemorrhage (ICH) has high morbidity, disability and mortality, it is significant to find new and effective treatments for ICH. This study aims to explore the effect of butyphthalide (NBP) on neuroinflammation secondary to ICH and microglia polarization.@*METHODS@#A total of 48 healthy male SD rats were randomly divided into 6 groups: a sham 24 h group, a sham 72 h group, an ICH 24 h group, an ICH 72 h group, an ICH+NBP 24 h group, and an ICH+NBP 72 h group (8 rats per group). After operation, the neurological deficiencies were assessed based on improved Garcia scores and corner test. The expressions of Toll-like receptor 4 (TLR4)/nuclear factor-kappa B (NF-κB), nuclear factor erythroid 2-related factor 2 (Nrf2), aquaporin-4 (AQP4), zonula occludens-1 (ZO-1), occludin, CD68, CD86, and CD206 were observed by Western blotting. Inflammatory cytokines were detected by ELISA. The immunofluorescence was to detect the polarization of microglia.@*RESULTS@#1) Compared with the sham groups, the expression of TLR4 (24 h: P<0.05; 72 h: P<0.01), NF-κB (both P<0.01) and Nrf2 (both P<0.01) in the perihematoma of the ICH group was increased, leading to microglia activation (P<0.01). The expressions of IL-6 (24 h: P<0.05; 72 h: P<0.01) and TNF-α (both P<0.01), the pro-inflammatory cytokines were up-regulated, and the expression of anti-inflammatory cytokine IL-4 was down-regulated (both P<0.01). Besides, the expression of AQP4 was enhanced (both P<0.01). The protein level of tightly connected proteins (including ZO-1, occludin) was decreased (all P<0.01). The neurological function of the rats in the ICH group was impaired in the 2 time points (both P<0.01). 2) Compared with the sham group at 24 h and 72 h after the intervention of NBP, the expressions of TLR4 (both P<0.05) and NF-κB (both P<0.01) were significantly declined, and the expression of Nrf2 was further enhanced (both P<0.05) in the perihematoma of the ICH+NBP group. Furthermore, the expression of M1 microglia marker was inhibited (P<0.05), and the polarization of microglia to the M2 phenotype was promoted (P<0.01). 3) In terms of inflammation after ICH, the IL-4 expression in the ICH+NBP group was increased compared with the ICH group (24 h: P<0.05; 72 h: P<0.01); the expression of IL-6 was decreased significantly in the ICH+NBP 72 h group (P<0.01); the level of AQP4 was declined significantly in the ICH+NBP 24 h group (P<0.05), there was a downward trend in the 72-hour intervention group but without significant statistical difference. 4) Compared with the ICH group, the ZO-1 protein levels were increased (24 h: P<0.05; 72 h: P<0.01), and the symptoms of nerve defect were improved eventually (both P<0.05) in the ICH+NBP groups.@*CONCLUSIONS@#After ICH, the TLR4/NF-κB pathway is activated. The M1 microglia is up-regulated along with the release of detrimental cytokines, while the anti-inflammatory cytokines are down-regulated. The expression of AQP4 is increased, the tight junction proteins from the blood-brain barrier (BBB) is damaged, and the neurological function of rats is impaired. On the contrary, NBP may regulate microglia polarization to M2 phenotype and play a role in the neuroprotective effect mediated via inhibiting TLR4/NF-κB and enhancing Nrf2 pathways, which relieves the neuroinflammation, inhibits the expression of AQP4, repairs BBB, and improves neurological functional defects.

Effect of C21 steroidal glycoside of Cynanchum auriculatum on liver and kidney fibrosis through TLR4 pathway / 中国中药杂志

The liver and kidney fibrosis model was established by thioacetamide(TAA) and unilateral ureteral obstruction(UUO) in SD rats. The rats were randomly divided into three groups: model group, low and high-dose groups of C21 steroidal glycosides of Cynanchum auriculatum. Another blank control group was set. Four weeks later, serum was taken to detect the biochemical indexes of liver and kidney function. Urine protein and urine creatinine were detected by kits. Liver and kidney tissue samples were stained with HE and Masson staining, and hydroxyproline content was detected. Western blot was used to detect expressions of fibrotic proteins, inflammatory factors and TLR4 signaling pathways, so as to observe the preventive and therapeutic effects of C21 steroidal glycosides from C. auriculatum on hepatic and renal fibrosis and explore its molecular mechanism. Four weeks later, serum biochemical results showed that liver and kidney functions were seriously damaged, and pathological sections showed that inflammatory cell infiltration, decrease of parenchymal cells, and increase of interstitial fibrosis in liver and kidney tissues. The results showed that low and high doses(150, 300 mg·kg~(-1)) of C21 steroidal glycosides could significantly reduce the collagen deposition and the pathological changes of liver and kidney fibrosis compared with the model group. At the same time, we found that the expression levels of TLR4 and MyD88 signaling pathway proteins were significantly increased in the liver and kidney tissues of the model group, and a large number of NF-κB signaling pathway proteins migrated into the nucleus. On the contrary, the expression levels of TLR4, MyD88 signaling pathway proteins and the nuclear migration of NF-κB were significantly inhibited in the low and high dose groups of C21 steroidal glycosides from C. auriculatum. Therefore, it was speculated that the mechanism of C21 steroidal glycoside for preventive and therapeutic effect on hepatic and renal fibrosis was related to inhibit TLR4/MYD88/NF-κB inflammatory pathway, thus preventing hepatic and renal fibrosis.

Effect of acupuncture on intestinal flora and TLR4 in brain and intestinal tissues in rats with stress gastric ulcer / 中国针灸

OBJECTIVE@#To observe the effect of acupuncture at "Guanyuan" (CV 4) and "Xiajuxu" (ST 39) on intestinal flora and Toll-like receptors-4 (TLR4) in brain and intestinal tissue in rats with stress gastric ulcer (SGU), and to explore the possible mechanism of acupuncture for SGU.@*METHODS@#Thirty-one male SD rats were randomly divided into a blank group (@*RESULTS@#Compared with the blank group, the gastric mucosal damage index was significantly increased in the model group (@*CONCLUSION@#Acupuncture at "Guanyuan" (CV 4) and "Xiajuxu" (ST 39) could alleviate SGU in rats, and its mechanism may be related to increasing the diversity of intestinal flora, promoting the disorder of intestinal flora to normal, and reducing the overexpression of TLR4 in brain and intestinal tissues.

Effect of electroacupuncture on expression of IL-23/IL-17 axis and TLR4 in infarcted tissue in rats with myocardial infarction / 中国针灸

OBJECTIVE@#To observe the effect of electroacupuncture (EA) on expression of interleukin (IL) -23/IL-17 axis and Toll-like receptor 4 (TLR4) in the infarcted tissue in rats with myocardial infarction (MI), and to explore the mechanism of EA on alleviating MI injury.@*METHODS@#Forty male SD rats were randomly divided into a sham-operation group, a sham-operation plus EA group, a model group and an EA group, 10 rats in each group. The MI models were established by ligation of left anterior descending coronary artery in the model group and EA group, while only threading was performed in the sham-operation group and sham-operation plus EA group. The rats in the sham-operation plus EA group and EA group were treated with EA at "Neiguan" (PC 6), disperse-dense wave, 2 Hz/100 Hz, 2 mA, once a day, 20 min each time, for 3 days. After the intervention, the ejection fraction (EF) was measured by echocardiography to evaluate the cardiac function; the infarct area was measured by TTC staining; the HE staining was used to observe the morphological changes of myocardial tissue; the levels of IL-23 and IL-17 in infarcted tissue were detected by ELISA; the protein expression of TLR4 in infarcted tissue was detected by Western blot.@*RESULTS@#Compared with the sham-operation group, the EF was decreased (@*CONCLUSION@#EA may alleviate the excessive inflammatory response after MI by inhibiting the expression of IL-23/IL-17 axis in MI rats, and TLR4 may be involved during the process.

miR-139-5p protects septic mice with acute lung injury by inhibiting Toll-like receptor 4/Myeloid differentiation factor 88/Nuclear factor-&mac_kgr; B signaling pathway

OBJECTIVES: To investigate the role of miR-139-5p and the TLR4/MyD88/NF-κB signaling pathway in acute lung injury in septic mice. METHOD: A total of 140 healthy male SPF C57BL/6 mice were divided into seven groups, i.e., Normal, Control, NC, miR-139-5p mimic, miR-139-5p inhibitor, TAK-242, and miR-139-5p inhibitor+TAK-242 groups. The levels of miR-139-5p, proteins related to the TLR4/MyD88/NF-κB signaling pathway (TLR4, MyD88, and p-NF-κB p50), and MPO, SOD, GSH, and MDA in lung tissue were measured. The lung tissue wet-to-dry mass ratio (W/D), arterial oxygen partial pressure (PaO2), and carbon dioxide partial pressure (PaCO2) were measured. RESULTS: A web-based bioinformatic tool predicted that MyD88 was a target of miR-139-5p, which was verified by a dual luciferase reporter assay. Compared with those in the Normal group, the levels of miR-139-5p, PaO2, SOD, and GSH were significantly lower, while those of TLR4, MyD88, p-NF-κB p50, W/D, PaCO2, IL-1β, TNF-α, IL-6, MPO, and MDA were higher in all other groups. Moreover, compared with their levels in the Control group, these indicators exhibited contrasting results in the miR-139-5p mimic and TAK-242 groups, but were similar in the miR-139-5p inhibitor group. In the miR-139-5p inhibitor+TAK-242 group, acute lung injury, aggravated by miR-139-5p inhibitor, was partially rescued by TAK-242. CONCLUSION: miR-139-5p inhibits the TLR4/MyD88/NF-κB signaling pathway to alleviate acute lung injury in septic mice.

Polymorphisms in genes TLR1, 2 and 4 are associated with differential cytokine and chemokine serum production in patients with leprosy

BACKGROUND Leprosy or hansen’s disease is a spectral disease whose clinical forms mostly depends on host’s immune and genetic factors. Different Toll-like receptors (TLR) variants have been described associated with leprosy, but with some lack of replication across different populations. OBJECTIVES To evaluate the role of polymorphisms in genes TLR1, TLR2 and TLR4 and susceptibility to leprosy in a genetic case control study; to verify the association between genotypes of these markers and the immunological profile in the serum of patients with leprosy. METHODS Pre-designed TaqMan® assays were used to genotype markers at TLR1 (rs4833095, rs5743551), TLR2 (rs7656411, rs3804099) and TLR4 (rs1927914, rs1927911). A panel of cytokines and chemokines was accessed by enzime-linked immunosorbent assay (ELISA) test in the serum of a subgroup of patients with and without leprosy reactions. FINDINGS Our results show an association between the T allele of rs3804099 at the TLR2 gene and increased risk for leprosy per se [Odds ratio (OR) = 1.296, p = 0,022]. In addition, evaluating the association between different genotypes of the TLR1, 2 and 4 markers and cytokine/chemokine serological levels, IL-17 appears as an immunological marker regulated by the polymorphism of the three TLR genes evaluated, whereas different TLR1 genotypes were associated with differential production of IL-12p40 and MCP-1(CCL2). Furthermore, other relevant serum markers such as CXCL-10 and IL-6 seemed to be regulated by TLR2 variants and IL-1β was related to TLR4 genotypes. MAIN CONCLUSIONS All together our data points that the tested TLR markers may have a regulatory role in the immunity against Mycobacterium leprae, by driving the host’s production of key cytokines and chemokines involved in the pathogenesis of this disease.

A meta-analysis of TLR4 and TLR9 SNPs implicated in severe malaria

Abstract Toll-like receptors (TLRs) are critical mediators of the inflammatory response to malarial infection, and gene polymorphisms affecting TLR function may be partially responsible for inter-individual variation in disease manifestation. However, there are inconsistencies in the associations of common genetic variants of TLR4 (D299G) and TLR9 (T-1237C and T-1486C) with malaria outcome. A comprehensive search was conducted to identify relevant and independent Plasmodium falciparum-infected case-control studies, and meta-analysis including six studies for each SNP was performed to obtain more precise estimates of the pooled effects of these variants. The results showed significant associations of the -1486C allele with the risk of severe malaria in allele contrast (T vs. C, p = 0.004, OR = 1.26) and homozygous (TT vs. CC, p = 0.03, OR = 1.51) genetic models. There was no association between the D299G or T-1237C variants and uncomplicated or severe malaria using any of the genetic models tested. However, in stratified analysis, -1237C was associated with the risk of severe malaria in Indian adults (TT vs. TC, p = 0.06, OR = 2.13; TT vs. TC+CC, p <0.00001, OR = 2.65), suggesting that our results must be considered preliminary. The robustness of -1486C as a risk factor warrants investigation into its functionality in malaria pathogenesis. Further, the lack of an association with the T-1237C variant was weak, and future studies examining more detailed individual data from different ethnic groups are essential for confirmation of its genetic contribution to malaria.

Different engagement of TLR2 and TLR4 in Porphyromonas gingivalis vs. ligature-induced periodontal bone loss

Abstract This study was conducted to investigate the roles of different Toll-like receptor (TLR) signaling in Porphyromonas gingivalis (P. gingivalis)-induced and ligature-induced experimental periodontal bone resorption in mice. Wild-type (WT), TLR2 knockout (KO), TLR4KO, and TLR2&4 KO mice with C57/BL6 background were divided into three groups: control, P. gingivalis infection, and ligation. Live P. gingivalis or silk ligatures were placed in the sulcus around maxillary second molars over a 2-week period. Images were captured by digital stereomicroscopy, and the bone resorption area was measured with ImageJ software. The protein expression level of gingival RANKL was measured by ELISA. The gingival mRNA levels of RANKL, IL-1β, TNF-α, and IL-10 were detected by RT-qPCR. The results showed that P. gingivalis induced significant periodontal bone resorption in WT mice and TLR2 KO mice but not in TLR4 KO mice or TLR2&4 KO mice. For all four types of mice, ligation induced significant bone loss compared with that in control groups, and this bone loss was significantly higher than that in the P. gingivalis infection group. RANKL protein expression was significantly increased in the ligation group compared with that in the control group for all four types of mice, and in the P. gingivalis infection group of WT, TLR2 KO, and TLR4 KO mice. Expression patterns of RANKL, IL-1β, TNF-α, and IL-10 mRNA were different in the P. gingivalis infection group and the ligation group in different types of mice. In summary, P. gingivalis-induced periodontal bone resorption is TLR4-dependent, whereas ligation-induced periodontal bone resorption is neither TLR2- nor TLR4-dependent.

Association between Toll-like receptor 4 Asp299Gly polymorphism and coronary heart disease susceptibility

Published data on the association between Toll-like receptor 4 (TLR4) Asp299Gly polymorphism and coronary heart disease (CHD) susceptibility are inconclusive. To derive a more precise estimation of the relationship, a meta-analysis was performed. English-language studies were identified by searching PubMed and Embase databases (up to November 2016). All epidemiological studies were regarding Caucasians because no TLR4 Asp/Gly and Gly/Gly genotypes have been detected in Asians. A total of 20 case-control studies involving 14,416 cases and 10,764 controls were included in the meta-analysis. Overall, no significant associations were found between TLR4 Asp299Gly polymorphism and CHD susceptibility in the dominant model (OR=0.89; 95%CI=0.74 to 1.06; P=0.20) pooled in the meta-analysis. In the subgroup analysis by CHD, non-significant associations were found in cases compared to controls. When stratified by control source, no significantly decreased risk was found in the additive model or dominant model. The present meta-analysis suggests that the TLR4 Asp299Gly polymorphism was not associated with decreased CHD risk in Caucasians.

Role of TLR4 gene polymorphisms in the colorectal cancer risk modulation in ethnic Kashmiri population - a case-control study

Background: Colorectal carcinogenesis has been found to be associated with the polymorphic status of Toll-like receptor 4 gene in various populations of the world

Aim: The aim of the study was to determine the genetic association of TLR4 gene polymorphisms [Asp299Gly and Thr399Ile] with disease susceptibility and risk development in colorectal cancer [CRC] patients of Kashmir, India

Materials and methods: Genotype frequencies of TLR4 polymorphisms [Asp299Gly and Thr399Ile] were compared between 120 CRC patients and 200 healthy controls using PCRRFLP method

Results: We did not find any significant association between the TLR4 gene polymorphisms and the CRC cases [p>0.05]. However CT genotype [Thr399Ile] showed modest elevated risk of the development of CRC [OR = 1.78 95% CI [0.88-3.5]]. Also G allele [AG genotype] of TLR-4 Asp299Gly polymorphism was found to be significantly associated with the male gender [p value = 0.006] and involvement of Nodes [p value = 0.01] whereas, T allele [CT genotype] of Thr399Ile polymorphism showed significant association with the smoking status [p value = 0.03]

Conclusion: Our results suggest that TLR4 gene polymorphism is not a key modulator of the risk of developing colorectal cancer in Kashmiri population

Clinical characteristics and frequency of TLR4 polymorphisms in Brazilian patients with ankylosing spondylitis / Características clínicas e frequência de polimorfismos em TLR4 em pacientes brasileiros com espondilite anquilosante

ABSTRACT Objectives: Innate immunity is involved in the physiopathology of ankylosing spondylitis (AS), with the participation of Gram-negative bacteria, modulation of human leukocyte antigen (HLA) B27 and the involvement of pattern recognition receptors, such as Toll-like receptors (TLRs). The aim of this study was to investigate the clinical characteristics and frequency of TLR4 polymorphisms (Asp299Gly and Thr 399Ile) in a cohort of Brazilian patients with AS. Methods: A cross-sectional study was carried out involving 200 patients with a diagnosis of AS and a healthy control group of 200 individuals. Disease activity, severity and functional capacity were measured. The study of TLR4 polymorphisms was performed using the restriction fragment length polymorphism method. HLA-B27 was analyzed by conventional polymerase chain reaction. The IBM SPSS Statistics 20 program was used for the statistical analysis, with p-values less than 0.05 considered significant. Results: Mean age and disease duration were 43.1 ± 12.7 and 16.6 ± 9.2 years, respectively. The sample was predominantly male (71%) and non-Caucasian (52%). A total of 66% of the group of patients were positive for HLA-B27. The sample of patients was characterized by moderate functional impairment and a high degree of disease activity. No significant association was found between the two TLR4 polymorphisms and susceptibility to AS. Conclusions: TLR4 polymorphisms 399 and 299 were not more frequent in patients with AS in comparison to the health controls and none of the clinical variables were associated with these polymorphisms.

RESUMO Objetivos: A imunidade inata está envolvida na fisiopatologia da espondilite anquilosante (EA), com a participação de bactérias gram-negativas, modulação do antígeno leucocitário humano (HLA) B27 e o envolvimento de receptores de reconhecimento de padrões, como os receptores Toll-like (TLR). O objetivo deste estudo foi investigar as características clínicas e a frequência de polimorfismos em TLR4 (Asp299Gly e Thr399Ile) em uma coorte de pacientes brasileiros com EA. Métodos: Fez-se um estudo transversal que envolveu 200 pacientes com diagnóstico de EA e um grupo controle saudável de 200 indivíduos. Mediram-se a atividade da doença, a gravidade e a capacidade funcional. O estudo dos polimorfismos em TLR4 foi feito com o método de polimorfismo de fragmentos de restrição. O HLA-B27 foi analisado por reação em cadeia da polimerase convencional. Usou-se o programa SPSS Statistics 20 da IBM para a análise estatística e foram considerados significativos valores de p inferiores a 0,05. Resultados: A média de idade e a duração da doença foram de 43,1 ± 12,7 e 16,6 ± 9,2 anos, respectivamente. A amostra foi predominantemente do sexo masculino (71%) e de não brancos (52%). Do grupo de pacientes 66% eram HLA-B27 positivos. A amostra de pacientes foi caracterizada por uma alteração funcional moderada e um elevado grau de atividade da doença. Não foi encontrada associação estatisticamente significativa entre os polimorfismos em TLR4 e a susceptibilidade à EA. Conclusões: Os polimorfismos em TLR4 399 e 299 não foram mais frequentes em pacientes com EA em comparação com controles saudáveis e nenhuma das variáveis clínicas esteve associada a esses polimorfismos.

Ação da proteína amiloide sérica A em melanomas / Activity of serum amyloid A protein in melanomas

Concentrações séricas basais da proteína amiloide sérica A (SAA) estão significativamente aumentadas em pacientes com câncer e alguns autores sugerem uma relação causal. Trabalho anterior do grupo mostrou que a SAA induz a proliferação de duas linhagens de glioblastoma humano e afeta os processos de invasividade in vitro, sustentando um papel pró-tumoral para esta proteína. Com base nesse trabalho, investigamos a abrangência dos efeitos de SAA para outro tipo de célula tumoral e para isso escolhemos um painel de linhagens de melanoma humano e uma linhagem primária obtida a partir de aspirado de linfonodo de paciente com melanoma, por nós isolada. Observamos que apesar da célula precursora de melanomas, isto é, melanócito, não produzir SAA, todas as linhagens de melanoma produziram a proteína e expressaram alguns dos seus receptores. Além disso, quando estas células foram estimuladas com SAA houve uma inibição da proliferação em tempos curtos de exposição (48 horas) e efeitos citotóxicos após um tempo maior (7 dias). A SAA também afetou processos de invasividade e a produção das citocinas IL-6, IL-8 e TNF-α. Aos avaliarmos o efeito da SAA na interação das células de melanoma com células do sistema imune, vimos que a SAA ativou uma resposta imune anti-tumoral aumentando a expressão de moléculas co-estumolatórias, como CD69 e HLA-DR, e sua função citotóxica. Ainda, vimos que a produção de TNF-α, IFN-γ, IL-10, IL-1ß e IL-8 estimuladas por SAA podem contribuir com os efeitos desta. De forma geral estes resultados nos levam a crer que a SAA tem atividade anti-tumoral em melanomas. Finalizando, com base na importância do desenvolvimento da resistência às terapias atuais para o melanoma, observamos que em células resistentes ao PLX4032, um inibidor de BRAF, os efeitos imunomodulatórios induzidos pela SAA estão abolidos, possivelmente identificando um novo componente da resistência

Basal serum concentrations of the protein serum amyloid A are significantly increased in cancer patients and some authors suggest a causal relationship. Previous work of our research group showed that SAA induces proliferation of two cell lines of human glioblastoma and affects invasiveness processes in vitro, supporting a pro-tumor role for this protein. Based on this work, we investigated the extent of SAA effects to another type of tumor cell and we chose a panel of human melanoma cell lines and primary line obtained from a patient with melanoma by lymph node aspirate. Melanoma cells were isolated by us. We observed that while the precursor cells of melanoma, melanocytes, do not produce SAA, all melanoma cell lines expressed the protein and produced some of their receptors. Moreover, when these cells were stimulated with SAA there was an inhibition of proliferation in short exposure times (48 hours) and cytotoxic effects after a longer period (7 days). SAA also affected invasive procedures and the production of the cytokines IL-6, IL-8 and TNF-α. To evaluate the SAA effect in the interaction of melanoma cells with immune system cells, we found that SAA activated an anti-tumor immune response by increasing the expression of co-estimulatory molecules such as CD69 and HLA-DR, and their cytotoxic function. Furthermore, we found that the production of TNF-α, IFN-γ, IL-10, IL-1ß and IL-8 stimulated by SAA can contribute to this effect. In general these results lead us to believe that the SAA has anti-tumor activity in melanomas. Finally, based on the importance of the resistance development to current therapies for melanoma we observed that in cells resistant to PLX4032, a BRAF inhibitor, the immunomodulatory effects induced by SAA are abolished, possibly identifying a new resistance component

Decreased expression of Toll-like receptor 4 and 5 during progression of prostate transformation in transgenic adenocarcinoma of mouse prostate mice

Chronic inflammation has been considered an important risk factor for development of prostate cancer. Toll-like receptors (TLRs) recognize microbial moieties or endogenous molecules and play an important role in the triggering and promotion of inflammation. In this study, we examined whether expression of TLR4 and TLR5 was associated with progression of prostate transformation in the transgenic adenocarcinoma of mouse prostate (TRAMP) model. The expression of TLR4 and TLR5 was evaluated by immunohistochemisty in formalin-fixed paraffin-embedded prostate tissue from wild-type (WT) and TRAMP mice. Normal prostate tissue from WT mice showed strong expression of TLR4 and TLR5. However, TLR4 expression in the prostate tissue from TRAMP mice gradually decreased as pathologic grade became more aggressive. TLR5 expression in the prostate tissue from TRAMP mice also decreased in low-grade prostate intraepithelial neoplasia (PIN), high-grade PIN and poorly differentiated adenocarcinoma. Overall, our results suggest that decreased expression of TLR4 and TLR5 may contribute to prostate tumorigenesis.

Association between Recent Acetaminophen Use and Asthma: Modification by Polymorphism at TLR4

The risk of asthma has been increasing in parallel with use of acetaminophen, which is a potential source of oxidative stress. Toll-like receptor 4 (TLR4) plays a critical role not only in innate immunity, but also in mediating reactive oxygen species induced inflammation. Therefore, we investigated associations between acetaminophen usage and TLR4 polymorphism on asthma and bronchial hyperresponsiveness (BHR). The number of 2,428 elementary school children in Seoul and Jeongeup cities was recruited. Subjects who used acetaminophen with a family history of asthma had an increased risk of both asthma diagnosis ever and current asthma. Individuals with CT+TT genotypes at the TLR4 polymorphism, in combination with acetaminophen usage, also demonstrated an increased risk of asthma diagnosis ever (aOR, 2.08; 95% confidence interval [CI], 1.10-3.92). Family history of asthma and acetaminophen usage were risk factors for BHR. Although TLR4 was not an independent risk factor for BHR, individuals with CT+TT genotypes at the TLR4 polymorphism had an increased risk of BHR when combined with acetaminophen usage (aOR, 1.74; 95% CI, 1.03-2.94). In conclusion, acetaminophen usage may be associated with asthma and BHR in genetically susceptible subjects. This effect may be modified by polymorphism at TLR4.

Association Between Toll-Like Receptors/CD14 Gene Polymorphisms and Inflammatory Bowel Disease in Korean Population

The innate immune response in patients who develop inflammatory bowel disease (IBD) may be abnormal. However, the exact role of Toll-like receptors (TLRs) / CD14 gene in the pathogenesis of IBD has not been fully elucidated. We aimed to investigate the association between polymorphisms of TLR1, 2, 4, 6, and CD14 gene and susceptibility to IBD in Korean population. A total 144 patients of IBD (99 patients with ulcerative colitis, 45 patients with Crohn's disease) and 178 healthy controls were enrolled. Using a PCR-RFLP, we evaluated mutations of TLR1 (Arg80Thr), TLR2 (Arg753Gln and Arg677Trp), TLR4 (Asp299Gly and Thr399Ile), TLR6 (Ser249Pro) genes and the -159 C/T promoter polymorphism of CD14 gene. No TLR polymorphisms were detected in Korean subjects. T allele and TT genotype frequencies of CD14 gene were significantly higher in IBD patients than in healthy controls. In subgroup analysis, T allelic frequency was higher in pancolitis phenotype of ulcerative colitis. In Korean population, the promoter polymorphism at -159 C/T of the CD14 gene is positively associated with IBD, both ulcerative colitis and Crohn's disease.

Anti-inflammatory Mechanism of Lactobacillus rhamnosus GG in Lipopolysaccharide-stimulated HT-29 Cell / 대한소화기학회지

BACKGROUND/AIMS: Probiotics are live non-pathogenic organisms that belong to the resident microflora, and confer health benefits by multiple mechanisms. Lactobacillus rhamnosus GG (LGG) is one of the probiotic bacteria that ameliorates intestinal injury and inflammation caused by various stimuli. We aimed to evaluate the anti-inflammatory effect and mechanism of LGG in lipopolysaccharide (LPS)-stimulated HT-29 cells. METHODS: HT-29 cells were stimulated with interleukin (IL)-1beta (2 ng/mL), tumor necrosis factor (TNF)-alpha (20 ng/mL), and LPS (20 microg/mL) in the presence or absence of LGG (107-109 colony forming units/mL). Production of the pro-inflammatory chemokine IL-8 was measured by ELISA and semi-quantitative PCR. Transcriptional activity of NF-kappaB-responsive gene was evaluated by luciferase assay with reporter gene. Toll-like receptor 4 (TLR4) mRNA expression was assessed by semi-quantitative PCR. The IkappaBalpha degradation was evaluated by western blot and intranuclear translocation of NF-kappaB was determined by western blot and immunofluorescence. RESULTS: LGG did not affect the viability of HT-29 cells. Pretreatment of HT-29 cells with LGG significantly blocked TNF-alpha, and LPS induced IL-8 activation at both mRNA and protein level (p<0.05). Pretreatment of HT-29 cells with LGG attenuated LPS-induced NF-kappaB nuclear translocation and also blocked LPS-induced IkappaBalpha degradation. LGG also down-regulated TLR4 mRNA activated by LPS. CONCLUSIONS: LGG attenuates LPS induced inflammation, and this may be associated with TLR4/NF-kappaB down-regulation.

Myeloid differentiation primary response protein 88 blockade upregulates indoleamine 2,3-dioxygenase expression in rheumatoid synovial fibroblasts

Indoleamine 2,3-dioxygenase (IDO) is a key negative regulator of immune responses and has been implicated in tumor tolerance, autoimmune disease and asthma. IDO was detected in the joint synovial tissue in the inflammatory microenvironment of rheumatoid arthritis (RA), but IDO expression in joint synovial tissue is not sufficient to overcome the inflamed synovial environment. This study aimed to unravel the mechanisms involving the failure to activate tolerogenic IDO in the inflamed joint. We demonstrate that both poly (I:C) and lipopolysaccharide (LPS) induce expression of IDO in synovial fibroblasts. However, inflammatory cytokines such as IL-17, TNF-alpha, IL-12, IL-23 and IL-16 did not induce IDO expression. Poly (I:C) appeared to induce higher IDO expression than did LPS. Surprisingly, toll-like receptor (TLR)4-mediated IDO expression was upregulated after depletion of myeloid differentiation primary response protein 88 (MyD88) in synovial fibroblasts using small interfering RNA (siRNA). IDO, TLR3 and TLR4 were highly expressed in synovial tissue of RA patients compared with that of osteoarthritis patients. In addition, RA patients with severe disease activity had higher levels of expression of IDO, TLR3 and TLR4 in the synovium than patients with mild disease activity. These data suggest that upregulation of IDO expression in synovial fibroblasts involves TLR3 and TLR4 activation by microbial constituents. We showed that the mechanisms responsible for IDO regulation primarily involve MyD88 signaling in synovial fibroblasts, as demonstrated by siRNA-mediated knockdown of MyD88.

Variant toll-like receptor4 [Asp299Gly and Thr399Ile alleles] and toll-like receptor2 [Arg753gln and Arg677Trp alleles] in colorectal cancer

The innate immune system recognizes the presence of bacterial products through the expression of a family of membrane receptors known as Toll-like receptors [TLRs]. Polymorphisms in TLRs have been shown to be associated with increased susceptibility to diseases such as inflammatory bowel disease. The aim of this study was to determine whether there was a correlation between polymorphisms of TLR4 [Asp299Gly; Thr399Ile] and TLR2 [Arg677Trp; Arg753Gln] genes and risk of colorectal cancer. DNA from 60 colorectal carcinoma patients from 3 major races in Malaysia [22 Malays, 20 Chinese and 18 Indians] and blood from 50 apparently healthy individuals were evaluated. Control group were matched to study group by race and age. The polymorphisms were determined by Polymerase Chain Reaction-Restriction Fragment Length Polymorphism [PCR-RFLP]. Genotyping results showed two out of sixty tumor specimens [3.3%] harbored both variant TLR4 Asp299Gly and Thr399Ile alleles. In contrast, DNA isolated from blood cells of 50 apparently healthy individuals harbored wild type TLR4. In the case of TLR2 Arg753Gln genotyping, all of the fifty normal and 60 tumors were of the wild type genotype. TLR2 Arg677Trp genotyping showed a heterozygous pattern in all samples. However, this may not be a true polymorphism of the TLR2 gene as it is likely due to a variation of a duplicated [pseudogene] region. There was only a low incidence [2/60; 3.3%] of TLR4 polymorphism at the Asp299Gly and Thr399Ile alleles in colorectal cancer patients. All normal and tumor samples harbored the wild type TLR2 Arg753 allele. Our study suggests that variant TLR4 [Asp299Gly and Thr399Ile alleles] as well as TLR2 [Arg753Gln allele] are not associated with risk of colorectal cancer

Association of Toll-Like Receptor Gene with Crohn's Disease in Koreans / 대한소화기학회지

BACKGROUND/AIMS: Toll-like receptors (TLRs) serve as pattern recognition receptors that recognize specific molecular patterns of pathogens and can mediate the production of proinflammatory cytokines. Recently, TLRs have been identified as susceptibility genes for Crohn's disease (CD) in several studies from Western populations. We investigated the association of genetic variations in TLR4 and TLR9 with CD in Korean population. METHODS: In 380 CD cases and 380 healthy controls, we performed genotyping for TLR4 Asp299Gly (rs4986790) and Thr399Ile (rs4986791). The genetic variations in the TLR9 -1237T/C (rs5743836) were also examined. RESULTS: Among CD patients genotyped for TLR4 Asp299Gly and TLR9 -1237T/C, none had variant alleles. Similarly, none of the subjects genotyped for TLR4 Thr399Ile showed genetic variations. CONCLUSIONS: Our results indicate that the major genetic variations in TLR4 and TLR9 are rare and may not be associated with susceptibility to CD in Koreans.

EC-18, a Synthetic Monoacetyldiacylglyceride, Inhibits Hematogenous Metastasis of KIGB-5 Biliary Cancer Cell in Hamster Model

EC-18 (monoacetyldiacylglyceride) stimulates T cell production of IL-2, IL-4, IL-12, IFN-gamma, and GM-CSF in vitro. To study the effects of these cytokines stimulated by EC-18 on cancer cells, we applied hamster biliary cancer model, a difficult cancer to treat. Cancer (KIGB-5) cells were given intravenously to produce hematogenous metastatic lung lesions which were treated with EC-18 at 10, 25, and 50 mg/kg/day respectively. The fourth group was untreated control. At 4th, 8th, and 12th week the lungs were examined. EC-18 treated groups showed only a few microscopic lung lesions and no evidence of metastatic lesion with highest dose whereas widespread gross lung lesions were observed in untreated control. To investigate whether the anti-tumor effect of EC-18 is associated with suppression of tumor cell Toll-like receptor 4 (TLR-4) expression in addition to stimulation of the immune cells, KIGB-5 cells were exposed to LPS with or without EC-18. TLR-4 mRNA and protein expression, measured by reverse transcriptase PCR (RT-PCR), real-time quantitative PCR and western blot analysis, showed suppression of TLR-4 expression in KIGB-5 cells treated with EC-18 compared with control. In conclusion, EC-18 has a significant anti-tumor effect in this experimental model of biliary cancer suggesting potential for clinical application to this difficult cancer.