Analysis of TLR4 and TLR2 polymorphisms in inflammatory bowel disease in a Guangxi Zhuang population

Orally Administered Lactobacillus rhamnosus CY12 Alleviates DSS-Induced Colitis in Mice by Restoring the Intestinal Barrier and Inhibiting the TLR4-MyD88-NF-κB Pathway via Intestinal Microbiota Modulation

Oral ingestion of probiotics is a promising approach to relieving inflammatory disease through regulating the gut microbiota. A newly discovered strain, Lactobacillus rhamnosus CY12 (LCY12), obtained from cattle-yak milk, displayed numerous probiotic properties. These included enhanced viability in low pH and bile environments, adhesion capabilities, and potent antimicrobial effects. The research aimed to explore the beneficial impacts of the novel LCY12 strain on colitis in mice induced by dextran sulfate sodium (DSS) and to elucidate the underlying molecular mechanisms. The results of the study showed that administration of LCY12 effectively helped to reduce the negative effects of DSS-induced body weight loss, disease activity index score, colon length shortening, loss of goblet cells, and overall histopathological scores in the intestines. Simultaneously, LCY12 administration significantly alleviated intestinal inflammation and safeguarded intestinal barrier integrity by enhancing IL-10 levels, while dampening IL-6, IL-1β, and TNF-α production. Additionally, LCY12 boosted the presence of tight junction proteins. Furthermore, LCY12 hindered the TLR4/MyD88/NF-κB signaling pathway by downregulating TLR4 and MyD88 expression, inactivating phosphorylated IκBα, and preventing translocation of NF-κB p65 from the cytoplasm to the nucleus. The LCY12 also increased specific intestinal microbial communities and short-chain fatty acid (SCFA) production. Altogether, LCY12 oral administration alleviated colitis induced with DSS in mice by improving intestinal barrier function and regulating inflammatory cytokines, SCFA production, and intestinal microbiota.

Tou Nong powder obstructs ulcerative colitis through the regulation of NF-κB/NLRP3/Caspase-1/GSDMD inflammasome pyroptotic pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Tou Nong Powder (TNP), a classical Chinese medicinal formula originated from the Chinese Ming Dynasty, has been applied to treat skin ulcers in patients with deficient constitutions. According to theory of traditional Chinese medicine, colonic ulcers share similar pathological conditions with skin ulcers, and consequently, TNP has been applied to ulcerative colitis (UC) safely and effectively.

AIM OF STUDY

To investigate whether TNP obstructs 2,4,6-trinitrobenzene sulfonic acid (TNBS) induced enteric inflammation through regulation of NLRP3 inflammasome and attenuating enteric pyroptosis.

MATERIALS AND METHODS

Network pharmacology and UPLC-Q-TOF/MS were operated to identify compounds and pharmacological potential targets. The therapeutic effects of TNP were assessed on TNBS induced colitis via general symptoms (disease activity index, colonic weight and length) and histopathological observation. The NF-κB/NLRP3/Caspase-1/GSDMD signaling pathway regulation was investigated by Western blot and real time reverse transcription polymerase chain reaction (RT-qPCR).

RESULTS

TNP ameliorates the disease activity index, reverses the increase of colonic weight increase, alleviates colonic shortening and colonic histopathological injury. A decrease in tumor necrosis factor α (TNF-α), diamine oxidase (DAO), intercellular adhesion molecule-1 (ICAM-1), and endo-toxin (ET) were investigated in peripheral circulation. Moreover, TNP significantly obstructed the NF-κB/NLRP3/Caspase-1/GSDMD signaling pathway.

CONCLUSION

TNP displays a promising therapeutic effect on UC via suppressing NF-κB/NLRP3/Caspase-1/GSDMD signaling pathway and reducing the expression of IL-1β and IL-18.

Polysaccharide from Smilax glabra Roxb Mitigates Intestinal Mucosal Damage by Therapeutically Restoring the Interactions between Gut Microbiota and Innate Immune Functions

Smilax glabra Roxb (S. glabra) is a conventional Chinese medicine that is mainly used for the reliability of inflammation. However, bioactive polysaccharides from S. glabra (SGPs) have not been thoroughly investigated. Here, we demonstrate for the first time that SGPs preserve the integrity of the gut epithelial layer and protect against intestinal mucosal injury induced by dextran sulfate sodium. Mechanistically, SGPs mitigated colonic mucosal injury by restoring the association between the gut flora and innate immune functions. In particular, SGPs increased the number of goblet cells, reduced the proportion of apoptotic cells, improved the differentiation of gut tight junction proteins, and enhanced mucin production in the gut epithelial layer. Moreover, SGPs endorsed the propagation of probiotic bacteria, including Lachnospiraceae bacterium, which strongly correlated with decreased pro-inflammatory cytokines via the blocking of the TLR-4 NF-κB and MyD88 pathways. Overall, our study establishes a novel use of SGPs for the treatment of inflammatory bowel disease (IBD)-associated mucosal injury and provides a basis for understanding the therapeutic effects of natural polysaccharides from the perspective of symbiotic associations between host innate immune mechanisms and the gut microbiome.

Combined treatment with Rg1 and adipose-derived stem cells alleviates DSS-induced colitis in a mouse model

Background

Inflammatory bowel diseases, consisting of Crohn’s disease and ulcerative colitis constitute chronic inflammatory conditions that may compromise the whole gastrointestinal tract as well as the colonic mucosa. Currently, there are no curative interventions for IBD, and all available treatments have side effects that limit their use. Adipose-derived stem cell (ADSC) treatment is a prospective treatment option for IBD. Previous findings indicated that ginsenoside (Rg1) dampened inflammatory diseases like colitis by inhibiting the binding of LPS to TLR4 on macrophages and restoring the Th17/Treg ratio. The purpose of this work was to investigate whether Rg1 can increase the influence of ADSC in a mouse model of colitis triggered by dextran sulfate sodium (DSS).

Methods

ADSC was intravenously inoculated into mice with DSS-triggered colitis, while Rg1 was delivered via oral gavage. Colon inflammation was assessed via body weight, colon length along with H&E staining. Serum cytokine levels were measured using ELISA. Besides, flow cytometry was adopted to determine the percentage, as well as FMI of immune cells in the spleen. The effects of simultaneous Rg1 and ADSC treatment on TLR4-MyD88 signaling were assessed via immunofluorescence.

Results

Rg1 and ADSC effectively alleviated the impacts of colon inflammation, weight loss, and colon length reduction along with histological score. Treatment with Rg1 and ADSC reduced serum levels of the proinflammatory cytokines, IL-1β, TNF-α, IL-6, IL-4, and IL-17A and upregulated the level of immunosuppressive cytokine, IL-10. Compared with ADSC or Rg1 alone, combined treatment with Rg1 and ADSC significantly improved the structure of microbial community. Additionally, treatment with Rg1 plus ADSC selectively elevated the level of splenic regulatory T (Treg) cells and downregulated the proportion of T helper type 17 (Th17) cells, indicating restoration of intestinal homeostasis. Besides, we established that the combination of ADSC + Rg1 restored immunological balance more effectively than either ADSC or Rg1 alone, illustrating that Rg1's modulatory function on the gut microbiota may boost the impact of ADSCs in restoration of the immune balance. ADSC combined with Rg1 might downregulate the expression of TLR4 and MyD88, thereby suppressing TLR4-MyD8 signaling. The immunofluorescence results also suggested that co-therapy with Rg-1 and ADSC may optimize treatment strategies of IBD.

Conclusions

Here, we find that the combination of Rg1 and ADSC alleviates DSS-induced colitis in a mouse model more efficiently than ADSC alone, indicating that Rg1 enhances the effect of ADSC against colitis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-022-02940-x.

Lactobacillus plantarum L15 Alleviates Colitis by Inhibiting LPS-Mediated NF-κB Activation and Ameliorates DSS-Induced Gut Microbiota Dysbiosis

Previous studies have suggested that the Lactobacillus plantarum bacteria strain could be effective in ulcerative colitis (UC) management. However, its effects are strain-specific and the related mechanisms for its attenuating effects on UC remain unclear. This study aimed to elucidate the underlying mechanisms for the protective effect of L. plantarum on UC. Firstly, 15 L. plantarum strains were screened for potential probiotic characteristics with good tolerance to simulated human gastrointestinal transit and adhesion. Secondly, the inflammatory response of selected strains to the Caco-2 cells induced by lipopolysaccharide (LPS) was measured. Finally, an in vivo mouse model induced by dextran sulfate sodium (DSS) was used to assess the beneficial effects and likely action mechanisms the successfully screened in vitro strain, L. plantarum L15. In vitro results showed that L. plantarum L15 possessed the highest gastrointestinal transit tolerance, adhesion and reduction of pro-inflammatory abilities compared to the other screened strains. In vivo, high dose of L. plantarum L15 supplementation increased the body weight, colon length and anti-inflammatory cytokine production. Pro-inflammatory cytokine production, disease activity index (DAI) levels and myeloperoxidase (MPO) parameters decreased using this strain. In addition, L. plantarum L15 alleviated the histopathological changes in colon, modulated the gut microbiota, and decreased LPS secretion. The activities of this strain down-regulated the expression of TLR4 and MyD88 genes as well as genes associated with NF-κB signaling pathway. Our findings present L. plantarum L15 as a new probiotic, with promising application for UC management.

TAK-242 ameliorates DSS-induced colitis by regulating the gut microbiota and the JAK2/STAT3 signaling pathway

Background

The goal of the present study was to investigate the effects of TAK-242 on the gut microbiota and the TLR4/JAK2/STAT3 signaling pathway in mice with dextran sulfate sodium (DSS)-induced colitis.

Results

At the phylum level, Bacteroidetes, Firmicutes, Actinobacteria, Cyanobacteria, Epsilonbacteraeota and Proteobacteria were the primary microbiota in the five groups. TAK-242 treatment significantly enhanced Verrucomicrobia and Actinobacteria; significantly decreased Cyanobacteria, Epsilonbacteraeota and Proteobacteria; and particularly promoted the growth of Akkermansia. TAK-242 markedly alleviated DSS-induced colitis symptoms and colonic lesions by promoting IL-10 release, inhibiting IL-17 release, downregulating TLR4 and JAK2/STAT3 mRNA and protein expression and increasing JAK2/STAT3 phosphorylation.

Conclusion

TAK-242 modulates the structure of the gut microbiota in colitis and may be a novel therapeutic candidate for ulcerative colitis.

The protective role of phloretin against dextran sulfate sodium-induced ulcerative colitis in mice

Phloretin, a dihydrogen chalcone flavonoid, is mainly isolated from apples and strawberries. Phloretin has been proven to have many biological activities such as anti-inflammatory and anti-oxidative. Herein, we investigated the protective efficacy and potential mechanism of phloretin in dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) in mice. The results showed that phloretin resulted in a reduced DSS-induced disease activity index (DAI), colon length shortening and colonic pathological damage. The levels of pro-inflammatory cytokines in the colon were also decreased by the administration of phloretin. Exploration of the potential mechanism demonstrated that phloretin suppressed the inflammatory response by regulating the nuclear factor-κB (NF-κB), toll-like receptor 4 (TLR4) and peroxisome proliferator-activated receptor γ (PPARγ) pathways. Phloretin also inhibited the DSS-induced (NOD)-like receptor family and pyrin domain containing 3 (NLRP3) inflammasome activations. Further studies found that phloretin reduced key markers of oxidative stress as well as regulated the expression of zonula occludens-1 (ZO-1) and occludin. Interestingly, the concentration of serum lipopolysaccharide (LPS) was significantly decreased. Escherichia coli (E. coli) and Lactobacillus levels were also re-balanced after phloretin treatment. These results indicate that phloretin might be a new dietary strategy for the treatment of UC.

The Correlation of Increased CRP Levels with NFKB1 and TLR2 Polymorphisms in the Case of Morbid Obesity

Morbid obesity (MO) is associated with an increase in circulating levels of systemic acute phase proteins such as C-reactive protein (CRP). Toll-like receptor is possible candidate for inflammatory responses which is mainly mediated by NFKB1. The aim of this study was to investigate the relationship between NFKB1 and Toll-like receptor (TLR) 2 polymorphisms and the risk of MO in a Turkish population in the context of CRP serum levels which may contribute to susceptibility to the disease. We analysed the distribution of NFKB1-94 ins/del ATTG rs28362491 and TLR2 Arg753Gln rs5743708 polymorphisms using PCR-RFLP method and CRP serum levels using ELISA method in 213 MO and 200 healthy controls. The frequency of the ins/ins genotype and ins allele of rs28362491 was significantly higher in the patients compared to control group (P: 0.0309; P: 0.0421, respectively). Additionally, the frequency of GG genotype and G allele of rs5743708 was found to be statistically higher in the patient group (P: 0.0421; P < 0.0001, respectively). In addition, serum CRP levels (>20 mg/l) in MO patients with ins/ins genotype were significantly higher than in patients with del/ins genotype (P: 0.0309). Serum CRP levels were also higher in MO patients with GG genotype and G allele (P: 0.0001). According to combined analysis, the wild type of rs28362491 and rs5743708 polymorphisms (ins/ins/GG genotype) was also significantly higher in the patient group versus the control group when compared with the combined ins/ins/GA and del/ins/GA genotype (P < 0.0001). Therefore, our findings suggest that rs28362491 and rs5743708 polymorphisms were significantly associated with MO disease through acting by modulating serum CRP levels.

Common NOD2/CARD15 and TLR4 Polymorphisms Are Associated with Crohn's Disease Phenotypes in Southeastern Brazilians

AIM

To investigate whether variants in NOD2/CARD15 and TLR4 are associated with CD and ulcerative colitis (UC) in a genetically admixed population of Rio de Janeiro, where IBD has continued to rise.

METHODS

We recruited 67 consecutive patients with CD, 61 patients with UC, and 86 healthy and ethnically matched individuals as controls. DNA was extracted from buccal brush samples and genotyped by PCR with restriction enzymes for G908R and L1007finsC NOD2/CARD15 single-nucleotide polymorphisms (SNPs) and for T399I and D299G TLR4 SNPs. Clinical data were registered for subsequent analysis with multivariate models.

RESULTS

NOD2/CARD15 G908R and L1007finsC SNPs were found in one and three patients, respectively, with CD. NOD2/CARD15 G908R and L1007finsC SNPs were not found in any patients with UC, but were found in three and three controls, respectively. With regard to the TLR4 gene, no significant difference was detected among the groups. Overall, none of the SNPs investigated determined a differential risk for a specific diagnosis. Genotype-phenotype associations were found in only CD, where L1007finsC was associated with colonic localization; however, TLR4 T399I SNP was associated with male gender, and D299G SNP was associated with colonic involvement, chronic corticosteroid use, and the need for anti-TNF-alpha therapy.

CONCLUSION

Variants of NOD2/CARD15 and TLR4 do not confer susceptibility to IBD, but appear to determine CD phenotypes in this southeastern Brazilian population.

Overexpression of HMGB1 A-box reduced lipopolysaccharide-induced intestinal inflammation via HMGB1/TLR4 signaling in vitro

AIM: To investigate the inhibitory effects and mechanism of high mobility group box (HMGB)1 A-box in lipopolysaccharide (LPS)-induced intestinal inflammation.

METHODS: Overexpression of HMGB1 A-box in human intestinal epithelial cell lines (SW480 cells) was achieved using the plasmid pEGFP-N1. HMGB1 A-box-overexpressing SW480 cells were stimulated with LPS and co-culturing with human monocyte-like cell lines (THP-1 cells) using a Transwell system, compared with another HMGB1 inhibitor ethyl pyruvate (EP). The mRNA and protein levels of HMGB1/toll-like receptor (TLR) 4 signaling pathways [including HMGB1, TLR4, myeloid differentiation factor88 (MYD88), Phosphorylated Nuclear Factor κB (pNF-κB) p65] in the stimulated cells were determined by real-time polymerase chain reaction and Western blotting. The levels of the proinflammatory mediators [including HMGB1, interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α] in the supernatants of the stimulated cells were determined by ELISA.

RESULTS: EP downregulated the mRNA and protein levels of HMGB1, inhibited the TLR4 signaling pathways (TLR4, MYD88 and pNF-κB p65) and reduced the secretion of proinflammatory mediators (HMGB1, IL-1β, IL-6 and TNF-α) in the SW480 and THP-1 cells activated by LPS but not in the unstimulated cells. Activated by LPS, the overexpression of HMGB1 A-box in the SW480 cells also inhibited the HMGB1/TLR4 signaling pathways and reduced the secretion of these proinflammatory mediators in the THP-1 cells but not in the transfected and unstimulated cells.

CONCLUSION: HMGB1 A-box, not only EP, can reduce LPS-induced intestinal inflammation through inhibition of the HMGB1/TLR4 signaling pathways.

Investigation of Toll-Like Receptor-2 (2258G/A) and Interferon Gamma (+874T/A) Gene Polymorphisms among Infertile Women with Female Genital Tuberculosis

BACKGROUND

Toll-like receptor 2 (TLR2) and interferon-gamma (IFN-γ) coordinate with a diverse array of cellular programs through the transcriptional regulation of immunologically relevant genes and play an important role in immune system, reproductive physiology and basic pathology. Alterations in the functions of TLR2 2258G (guanine)/ A, IFN-γ (+874T/A) and signalling molecules that result from polymorphisms are often associated with susceptibility or resistance, which may, in turn, establish the innate host response to various infectious diseases. Presently, we proposed to investigate the risk of common single nucleotide polymorphism (SNP) of TLR2 and IFN-γ genes, for their effect on infertility in women with female genital tuberculosis (FGTB) and healthy women as controls.

METHODOLOGY/PRINCIPAL FINDINGS

Genotyping of TLR2 and IFN-γ gene polymorphisms was performed by amplification refractory mutation system multi-gene/multi-primer polymerase chain reaction followed by restriction fragment length polymorphism in 175 FGTB patients and 100 healthy control women (HCW). The TLR2 polymorphism [adenine (A) allele] was observed in 57.7 and 58.0% of FGTB patients and HCW, respectively. The IFN-γ (+874T/A) polymorphism (A allele) was significant in 74.3 and 71.0% of FGTB patients and HCW, respectively, while the odds ratios for the AA and TA genotypes for predisposition of FGTB were found to be 0.304 and 1.650 in HCW, respectively. The SNP of TLR2 was not associated with FGTB but the SNP of IFN-γ was found to be associated with mycobacteria infections and to induce infertility.

CONCLUSIONS/SIGNIFICANCE

At present, we hypothesize that infertile women with FGTB and HCW without tuberculosis (TB) have identical frequency of TLR variants, which may be adequate in the production of IFN-γ in response to Mycobacterium tuberculosis infections. Thus, the study appears to be the first of its kind reporting a mutation in the IFN-γ gene [+874 T (thymine) to A] responsible for susceptibility to TB infections and further inducing infertility.

Wogonin suppresses inflammatory response and maintains intestinal barrier function via TLR4-MyD88-TAK1-mediated NF-κB pathway in vitro

AIMS AND OBJECTIVE

Wogonin has multiple pharmacological effects, including anti-inflammatory effects. Here, we hypothesize that wogonin can protect intestinal barrier function in lipopolysaccharide (LPS)-induced Caco-2 cells, which is an in vitro model of intestinal inflammation.

METHODS

We measured intestinal barrier function in LPS-induced Caco-2 cells by using transepithelial electrical resistance (TEER) and transport of fluorescent markers. A quantitative (q) RT-PCR and immunofluorescent staining analysis was used to detect the expression of tight junction proteins (claudin-1 and ZO-1) in LPS-induced Caco-2 cells. We measured inflammatory molecules in LPS-induced Caco-2 cells using ELISA and qRT-PCR. In addition, the expression of TLR4, MyD88 and TAK1 and their interaction, and NF-κB activity in LPS-induced Caco-2 cells were investigated by western blot analysis and immune-precipitation.

RESULTS

We found that exposing Caco-2 cells to wogonin (10 and 50 μM for 24 h) attenuated the LPS-induced changes in TEER and transport of fluorescent markers. In addition, wogonin suppressed LPS-induced down-regulation of tight junction proteins (claudin-1 and ZO-1). Furthermore, LPS-induced up-regulation of inflammatory mediators, including interleukin (IL)-1β, IL-6 and IL-8, cyclooxygenase-2 (COX-2), inducible nitric oxide synthases (iNOS) were reduced after being pre-treated with wogonin. Moreover, wogonin not only inhibited the expression of TLR4, MyD88 and TAK1 and the interaction between these molecules, but also reduced NF-κB translocation to nucleus and its DNA-binding activity in LPS-induced Caco-2 cells.

CONCLUSION

Our results suggested that pre-treatment with wogonin could attenuate the TLR4-mediated inflammatory response and maintain intestinal barrier function in LPS-induced Caco-2 cells, thus might be a potential therapy for treating IBD.

Association of TLR5 gene polymorphisms in ulcerative colitis patients of north India and their role in cytokine homeostasis

Background and Aim

In health, TLR signaling protects the intestinal epithelial barrier and in disease, aberrant TLR signaling stimulates diverse inflammatory responses. Association of TLR polymorphisms is ethnicity dependent but how they impact the complex pathogenesis of IBD is not clearly defined. So we propose to study the status of polymorphisms in TLR family of genes and their effect on cytokines level in UC patients.

Methods

The genotypes of the six loci TLR1-R80T, TLR2-R753Q, TLR3-S258G, TLR5-R392X, TLR5-N592S and TLR6-S249P were determined in 350 controls and 328 UC patients by PCR-RFLP and sequencing. Cytokine levels were measured by ELISA in blood plasma samples. Data were analyzed statistically by SPSS software.

Results

TLR5 variants R392X and N592S showed significant association (p = 0.007, 0.021) with UC patients but TLR 1, 2, 3, 6 variants did not show any association. Unlike other studies carried out in different ethnic groups, TLR 6 (S249P) SNP was universally present in our population irrespective of disease. Genotype-phenotype correlation analysis revealed that the patients having combination of multiple SNPs both in TLR5 and TLR4 gene suffered from severe disease condition and diagnosed at an early age. The level of TNFα (p = 0.004), IL-6 (p = 0.0001) and IFNγ (p = 0.006) significantly increased in patients as compared to controls having wild genotypes for the studied SNPs. However, there was decreased level of TNFα (p = 0.014), IL-6 (p = 0.028) and IFNγ (p = 0.001) in patients carrying TLR5-R392X variant as compared to wild type patients. Patients carrying two simultaneous SNPs D299G in TLR4 gene and N592S in TLR5 gene showed significant decrease in the levels of TNFα (p = 0.011) and IFNγ (p = 0.016).

Conclusion

Polymorphisms in TLR 5 genes were significantly associated with the UC in North Indian population. The cytokine level was significantly modulated in patients with different genotypes of TLR4 and TLR5 SNPs.

Toll-like receptor 4 Asp299Gly and Thr399Ile polymorphisms: New data and a meta-analysis

Background

The pathogenesis of inflammatory bowel disease (IBD) involves interactions between the host genetic susceptibility, intestinal microflora and mucosal immune responses through the pattern recognition receptor. Polymorphisms in toll-like receptor 4 (TLR4) induce an aberrant immune response to indigenous intestinal flora, which might favor IBD development. In this study, we aimed to determine whether TLR4 gene was associated with Crohn’s disease (CD) and ulcerative colitis (UC) among Moroccan patients, and evaluated its correlation with clinical manifestation of the disease.

Methods

The study population comprised 117 patients with IBD and 112 healthy unrelated blood donors. TLR4 polymorphisms: Asp299Gly and Thr399Ile were genotyped by polymerase chain reaction-restriction fragment length polymorphism. PCR products were cleaved with Nco I for the Asp299Gly polymorphism and Hinf I for the Thr399Ile polymorphism. Meta-analysis was performed to test the association of 299Gly and 399Ileu carriage with CD, UC and the overall IBD risk.

Results

Our study revealed that the frequency of Asp299Gly and Thr399Ile did not differ significantly between patients and controls in the Moroccan population. However, meta-analysis demonstrated significantly higher frequencies of both Asp299Gly and Thr399Ile SNPs in IBD and CD and for 399Ileu carriage in UC patients.

Conclusion

The meta-analysis provides evidence that TLR4 polymorphisms confer a significant increased risk for the overall IBD development.

TLR4 and TLR9 Polymorphisms Effect on Inflammatory Response in End-Stage Renal Disease Patients

Toll-like receptors (TLRs) play a key role in the response of innate and adaptive immune system to microbial and endogenous ligands. Inflammation is a common feature in end-stage renal disease (ESRD) patients; however, the mechanisms/factors triggering the inflammatory process are still poorly clarified. Our aim was to analyze the impact of the c.-1486T>C and c.896A>G polymorphisms in TLR9 and TLR4 genes, respectively, on the inflammatory response of ESRD patients. Clinical and laboratory evaluation was carried out on 184 ESRD patients. Polymerase chain reaction followed by restriction fragmens length polymorphisms (PCR-RFLP) was employed for genotyping of TLR-4 c.896A>G and TLR-9 c.-1486T>C polymorphisms. The prevalence of AA and AG of TLR4 c.896A>G polymorphism in ESRD patients was 97.8% and 2.2%, respectively. None of the individuals showed a homozygous TLR4 polymorphism. Concerning the TLR9 c.-1486T>C polymorphism, we found that ESRD patients showed a prevalence of TC and CC genotypes of 57.1% and 20.6%, respectively. We found that the heterozygous patients for the TLR4 c.896A>G polymorphism presented an increased level in lymphocyte count, a decrease in neutrophil/lymphocyte ratio and in serum levels of hepcidin. Regarding the TLR9 c.-1486T>C polymorphism, we found that it is associated with decreased white blood cell and neutrophil counts, ferritin and CRP serum levels, and with an increase in serum levels of creatinine. Our data suggest that the presence of the studied polymorphisms is associated with a decreased inflammatory response in ESRD patients under hemodialysis, and, thus its presence might have beneficial effects in ESRD patients. Moreover, our data provide new insights in the role of TLR polymorphisms in renal disease, which might have impact in the near future for the development of innovative therapies.

Association between NOD2/CARD15 gene polymorphisms and Crohn's disease in Chinese Zhuang patients

AIM: To assess the relationship between the P268S, JW1 and N852S polymorphisms and Crohn’s disease (CD) susceptibility in Zhuang patients in Guangxi, China.

METHODS: Intestinal tissues from 102 Zhuang [48 CD and 54 ulcerative colitis (UC)] and 100 Han (50 CD and 50 UC) unrelated patients with inflammatory bowel disease and 72 Zhuang and 78 Han unrelated healthy individuals were collected in the Guangxi Zhuang Autonomous Region from January 2009 to March 2013. Genomic DNA was extracted using the phenol chloroform method. The P268S, JW1 and N852S polymorphisms were amplified using polymerase chain reaction (PCR), detected by restriction fragment length polymorphism (RFLP), and verified by gene sequencing.

RESULTS: Heterozygous mutation of P268S in the NOD2/CARD15 gene was detected in 10 CD cases (six Zhuang and four Han), two Han UC cases, and one Zhuang healthy control, and P268S was strongly associated with the Chinese Zhuang and Han CD populations (P = 0.016 and 0.022, respectively). No homozygous mutant P268S was detected in any of the groups. No significant difference was found in P268S genotype and allele frequencies between UC and control groups (P > 0.05). Patients with CD who carried P268S were likely to be ≤ 40 years of age (P = 0.040), but were not significantly different with regard to race, lesion site, complications, and other clinical features (P > 0.05). Neither JW1 nor N852S polymorphisms of the NOD2/CARD15 gene were found in any of the subjects (P > 0.05).

CONCLUSION: P268S polymorphism may be associated with CD susceptibility in the Zhuang population in the Guangxi Zhuang Autonomous Region, China. In contrast, JW1 and N852S polymorphisms may not be related to CD susceptibility in these patients.

Association of Toll-like receptor 2 polymorphisms with gout

Gout is the most common autoinflammatory arthritis characterized by elevated serum urate and recurrent attacks of intra-articular crystal deposition of monosodium urate (MSU) in tissues. The pathogenesis of gout has not been fully determined, although certain genetic factors are involved in the development of gout. Accumulated data suggested that MSU crystal-induced inflammation is a paradigm of innate immunity. As Toll-like receptors (TLRs) are the underlying mechanisms of the innate immune response, the present study aimed to investigate whether TLR2 polymorphisms are associated with gout. Two single-nucleotide polymorphisms (Arg677Trp and Arg753Gln, rs5743708) in TLR2 were genotyped by polymerase chain reaction-restriction fragment length polymorphism and the -196 to -174 del polymorphism was investigated using the allele-specific polymerase chain reaction in 431 individuals (215 patients with gout and 216 healthy controls). TLR2 Arg677Trp and Arg753Gln genotyping indicated that all the positive samples were of the wild-type genotype. No significant differences in genotype (χ²=1.686, P=0.430) and allele (χ²=1.430, P=0.232) frequencies of the -196 to -174 del polymorphism between the patients with gout and the control groups was observed. Our results suggested that the TLR2 Arg677Trp, Arg753Gln and the -196 to -174 del polymorphisms were not associated with susceptibility to primary gouty arthritis.

Association of 10q21 gene rs10761659 polymorphism with susceptibility to inflammatory bowel disease in a Guangxi Zhuang population

AIM: To analyze the association of 10q21 gene rs10761659 polymorphism with susceptibility to inflammatory bowel disease (IBD) in a Zhuang population from Guangxi, China.

METHODS: A case-control study was conducted from August 2009 to October 2012, which included intestinal tissue samples of 73 Zhuang and 67 Han unrelated IBD patients and 70 Zhuang and 78 Han unrelated healthy volunteers in Guangxi. Genomic DNA was extracted from intestinal tissue using the phenol-chloroform method. The rs10761659 locus of the 10q21 gene was amplified by polymerase chain reaction (PCR), genotyped by restriction fragment length polymorphism (RFLP) and verified by gene sequencing.

RESULTS: The homozygous mutant, heterozygous mutant and wild-type genotypes of the rs10761659 locus were found in both IBD patients and healthy controls, but the distribution of genotypes and allele frequencies was not significantly different among Crohn's disease, ulcerative colitis and control groups (P > 0.05). No significant difference was detected in the 10q21 gene rs10761659 polymorphism between Zhuang and Han patients with Crohn's disease or ulcerative colitis (P > 0.05).

CONCLUSION: The rs10761659 polymorphism of the 10q21 gene is not associated with susceptibility to IBD in the Zhuang population in Guangxi.