Association of TNF-alpha serum levels and TNFA promoter polymorphisms with risk of myocardial infarction

M1-Type Macrophages Secrete TNF-α to Stimulate Vascular Calcification by Upregulating CA1 and CA2 Expression in VSMCs

Purpose

Vascular calcification is a hallmark of atherosclerosis (AS). We and others confirmed that carbonic anhydrase I (CA1) and CA2 increased expression and catalyzed calcium deposition in atherosclerotic aortas. Macrophages have been demonstrated to be strongly related to AS. This study aimed to clarify how and which macrophage subtypes regulate CA1 and CA2 expression to stimulate aortic calcification.

Methods and Results

THP-1 cells were induced to form M0, M1 and M2 macrophage subtypes. These cells and their culture supernatants were separately incubated with human vascular smooth muscle cells (VSMCs). Calcification was strongly increased in VSMCs treated with β-GP, a chemical inducer of cellular calcification, following incubation with M1 macrophages or their culture supernatants, and was much higher than that in VSMCs treated with β-GP alone. Meanwhile, the expression of CA1 and CA2, as well as calcification marker genes, including Runx2, BMP-2 and ALP, was increased in VSMCs during this process. TNF-α levels were also increased in the culture medium of M1 macrophages. M0 and M2 macrophages or their supernatants did not significantly stimulate calcification in VSMCs. Following transfection with anti-CA1 or CA2 siRNAs, β-GP-induced VSMCs showed decreased calcification, but the calcification level was partially increased when those VSMCs were incubated with the supernatants of M1 macrophages, while CA1 and CA2 expression as well as TNF-α levels were also elevated. When VSMCs were treated with TNF-α without β-GP induction, calcification and the expression of CA1 and CA2 were also significantly increased.

Conclusion

The results of this study suggest that M1 macrophages can increase CA1 and CA2 expression to promote atherosclerotic calcification in VSMCs by secreting TNF-α.

The Obese Brain: Mechanisms of Systemic and Local Inflammation, and Interventions to Reverse the Cognitive Deficit

Overweight and obesity are now considered a worldwide pandemic and a growing public health problem with severe economic and social consequences. Adipose tissue is an organ with neuroimmune-endocrine functions, which participates in homeostasis. So, adipocyte hypertrophy and hyperplasia induce a state of chronic inflammation that causes changes in the brain and induce neuroinflammation. Studies with obese animal models and obese patients have shown a relationship between diet and cognitive decline, especially working memory and learning deficiencies. Here we analyze how obesity-related peripheral inflammation can affect central nervous system physiology, generating neuroinflammation. Given that the blood-brain barrier is an interface between the periphery and the central nervous system, its altered physiology in obesity may mediate the consequences on various cognitive processes. Finally, several interventions, and the use of natural compounds and exercise to prevent the adverse effects of obesity in the brain are also discussed.

Inflammatory Markers in Cardiovascular Disease; Lessons Learned and Future Perspectives

BACKGROUND

Cardiovascular disease (CVD) still remains the leading cause of morbidity and mortality worldwide. It is now established that inflammation plays a crucial role in atherosclerosis and atherothrombosis, and thus, it is closely linked to cardiovascular disease.

OBJECTIVE

The aim of the present review is to summarize and critically appraise the most relevant evidence regarding the potential use of inflammatory markers in the field of CVD.

METHODS

We conducted a comprehensive research of the relevant literature, searching MEDLINE from its inception until November 2018, primarily for meta-analyses, randomized controlled trials and observational studies.

RESULTS

Established markers of inflammation, mainly C-reactive protein, have yielded significant results both for primary and secondary prevention of CVD. Newer markers, such as lipoprotein-associated phospholipase A2, lectin-like oxidized low-density lipoprotein receptor-1, cytokines, myeloperoxidase, cell adhesion molecules, matrix metalloproteinases, and the CD40/CD40 ligand system, have been largely evaluated in human studies, enrolling both individuals from the general population and patients with established CVD. Some markers have yielded conflicting results; however, others are now recognized not only as promising biomarkers of CVD, but also as potential therapeutic targets, establishing the role of anti-inflammatory and pleiotropic drugs in CVD.

CONCLUSION

There is significant evidence regarding the role of consolidated and novel inflammatory markers in the field of diagnosis and prognosis of CVD. However, multimarker model assessment, validation of cut-off values and cost-effectiveness analyses are required in order for those markers to be integrated into daily clinical practice.

TNF-α polymorphisms might influence predisposition to periodontitis: A meta-analysis

BACKGROUND

Tumor necrosis factor-α (TNF-α) polymorphisms might influence predisposition to periodontitis, but the results of already published studies were still controversial and ambiguous. So the authors designed this meta-analysis to more precisely estimate relationship between TNF-α polymorphisms and periodontitis by pooling the results of already published related studies.

METHODS

The authors searched Pubmed, Embase, Web of Science and CNKI for already published studies. Forty-five already published studies were pooled analyzed in this meta-analysis.

RESULTS

The crude pooled meta-analyses results showed that distributions of TNF-α rs361525, rs1800629, rs1800630 and rs1799964 polymorphisms among patients and controls differed significantly, which suggested that these polymorphisms might influence predisposition to periodontitis in the general population. We also got similar significant results for rs361525, rs1800629, rs1800630 and rs1799964 polymorphisms in subgroup analyses in Asians. The crude findings were further subjected to Bonferroni correction to account for multiple comparisons. For rs361525, rs1800629 and rs1799964 polymorphisms, basically no changes of results were detected. But for rs1800630 polymorphism, the results were no longer significant after adjustment for multiple comparisons.

CONCLUSIONS

This meta-analysis suggested that TNF-α rs361525, rs1800629 and rs1799964 polymorphisms might influence predisposition to periodontitis, particularly in Asians.

Glatiramer acetate protects against oxygen-glucose deprivation/reperfusion-induced injury by inhibiting Egr-1 in H9c2 cells

Myocardial infarction (MI) or heart attack is a deadly event with high prevalence. In the present study, we investigated the effects of the polypeptide copolymer glatiramer acetate (GA) in H9c2 rat cardiomyocytes exposed to oxygen-glucose deprivation/reperfusion injury. Immediately following MI, an acute inflammatory response is triggered that causes activation of various proinflammatory cytokines, infiltration of immune cells, and neovascularization. This response is largely mediated by some genes such as TNF-α, IL-6, ICAM-1, and VEGF. Additionally, the rapid influx of oxidants, such as reactive oxygen species (ROS), leads to a harmful state of oxidative stress. Here, we found that GA could reduce OGD/R-induced inflammation and oxidative stress by inhibiting the expression of TNF-α, IL-6, ICAM-1, and VEGF, and suppressing the production of ROS via reduced NADPH oxidase 1 (NOX1) expression. To elucidate the pathways involved in these promising results, we took a close look at the impact of the endothelial growth response-1 (Egr-1), a transcriptional factor recognized as a mediator of MI-related inflammation and cellular injury. Using siRNA for Egr-1, we found that GA could reduce the expression of ICAM-1 and VEGF by inhibiting Egr-1 expression. Together, our findings indicate a novel therapeutic potential of GA in the treatment of MI.

Association of tumor necrosis factor-α gene polymorphisms and coronary artery disease susceptibility: a systematic review and meta-analysis

Background

The goal of this study was to review relevant case-control studies to determine the association of tumor necrosis factor-α (TNF-α) gene polymorphisms and coronary artery disease (CAD) susceptibility.

Methods

Using appropriate keywords, we identified relevant studies using PubMed, Cochrane, Embase, CNKI, VANFUN, and VIP. Key pertinent sources in the literature were also reviewed, and all articles published through April 2019 were considered for inclusion. Based on eligible studies, we performed a meta-analysis of association between 308G/A, 238G/A, 857C/T, 863C/A and 1031 T/C polymorphisms in TNF-α and risk of CAD.

Results

We found 25 studies that were consistent with this meta-analysis, including 7697 patients in the CAD group and 9655 control patients. TNF-α 308G/A locus A showed no significant association with CAD susceptibility by the five models in the analysis of the overall population, European, African, South Asian, and North Asian patients. TNF-α 863C/A locus A and 1031 T/C locus C exhibited no significant association with CAD susceptibility. TNF-α 238G/A locus A had no significant association with CAD susceptibility in the overall population. However, TNF-α 238G/A locus A showed significant association with higher CAD susceptibility in the subgroup of Europeans and north Asians. TNF-α 857C/T locus T had no significant association with CAD susceptibility in the analysis of the overall population and Europeans. In the north Asian population, TNF-α 857C/T locus T was associated with lower CAD susceptibility by the heterozygote model.

Conclusion

TNF-α 308G/A, 857C/T, 863C/A, and 1031 T/C has no significant association with CAD susceptibility. TNF-α 238G/A locus A has significant association with CAD susceptibility in Europeans and north Asians, but has no significant association in the overall population. Studies with a larger sample size are required to confirm the association between TNF-α 238G/A and CAD susceptibility.

Polymorphisms of cytokine genes and tuberculosis in two independent studies

Cytokine gene single nucleotide polymorphisms (SNPs) can influence cytokine levels, which may be associated with tuberculosis (TB) susceptibility. There is evidence that interleukin 1B (IL1B), tumor necrosis factor-alpha (TNF-alpha), and IL6 may be involved in the progression of TB. Using a self-validating case-control design, we selected eleven functional SNPs in IL1B, TNF and IL6 to detect their association with TB in Chinese Han and Tibetan populations. The associations between SNPs and TB were estimated by computing the odds ratios (ORs) and 95% confidence intervals (95% CI) using logistic regression analyses. We found that the IL1B rs16944 polymorphism was associated with decreased risk of TB in the two studies. The G allele at rs2069837 of IL6 was significantly more common in controls than in TB patients in the Han population. Moreover, TNF rs1799964 and rs1800630 were risk factors for susceptibility to TB, which were validated in the Chinese Tibetan population. In addition, TNF rs1799724 and rs1800629 were associated with TB, but only in the Tibetan population. In conclusion, SNPs of the IL1B and TNF gene were associated with TB susceptibility in Chinese Han and Tibetan populations. IL6 polymorphism may be considered as a protective factor for TB in the Chinese Han population, but not the Tibetan population.

Promoter variants of TNF-α rs1800629 and IL-10 rs1800871 are independently associated with the susceptibility of coronary artery disease in north Indian

BACKGROUND

Tumor necrosis factor-alpha (TNF-α) are considered as a pro inflammatory and interleukin-10 (IL-10) anti inflammatory have been shown to predict the risk of incident of coronary artery disease (CAD). The polymorphism at promoter of TNF-α and IL-10 has been shown to increase transcriptional activity of the gene and play a important role in patho physiology of CAD. Aim of present study is to examine the impact of the TNF-α and IL-10 variant allele on various markers of the CAD and to study its relation with circulating TNF-α and IL-10 levels.

METHODS

The -308 G/A & -238 G/A of TNF-α and -1082 G/A & -819 C/T of IL-10 gene polymorphism has been studied in 301 diagnosed CAD subjects (Age 51.50 ± 9.28; BMI 25.30 ± 3.58) and 305 healthy controls (Age 51.57 ± 9.50; BMI 24.06 ± 7.26). These polymorphism of TNF-α and IL-10 were detected by real time PCR by using Taqman SNP genotyping assay. Furthermore serum TNF-alpha and IL-10 levels were also measured by ELISA.

RESULTS

Allelic and genotypic frequencies did not deviate from Hardy-Weinberg equilibrium in the controls (p > 0.05). On allele contrast, significant association with susceptibility to CAD was detected with polymorphisms in TNF-α -308 G/A, that variant genotype GA + AA (dominant model) (p = 0.030: OR = 1.61: 95% CI = 1.06-2.44) and variant allele (A) (p = 0.006: OR = 1.71: 95% CI = 1.17-2.51) of TNF-α 308 G/A gene was significant highly observed in the cases as compared to control group. Furthermore, variant genotype CT + TT (dominant model) (p = 0.004: OR = 1.62: 95% CI = 1.17-2.24) and variant allele (T) (p < 0.001: OR = 1.49: 95% CI = 1.17-1.89) of IL-10 -819 C/T gene was significant highly observed in the cases as compared to control group.

CONCLUSION

Our results suggest that the TNF-α G-308A polymorphism independently associated with DBP, cholesterol, triglyceride, LDL, TNF-α and IL-10 levels which may be leads to the development of coronary artery disease of North Indians.

Tumor necrosis factor-alpha gene polymorphisms and susceptibility to ischemic heart disease: A systematic review and meta-analysis

BACKGROUND

A number of studies had reported the association between tumor necrosis factor-alpha (TNF-α) gene polymorphisms and ischemic heart disease (IHD) risk. However, the results remained controversial. Therefore, we performed a systematic review with multiple meta-analyses to provide the more precise estimations of the relationship.

METHODS

We systematically searched electronic databases (PubMed, the Web of Science, EMBASE, Medline, Chinese National Knowledge Infrastructure, WanFang and ChongQing VIP Database) for relevant studies published up to February 2017. The odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for assessing the association. The present meta-analysis was performed using STATA 12.0 software.

RESULTS

In total, 45 articles with 17,375 cases and 15,375 controls involved were included. Pooled ORs revealed a significant association between TNF-α -308G/A gene polymorphism and IHD (A vs. G: OR = 1.22, 95% CI = 1.10-1.35; (AA + GA) vs. GG: OR = 1.18, 95% CI = 1.03-1.36; (AA vs. (GA+GG): OR = 1.37, 95% CI = 1.08-1.75)), indicating that the TNF-α -308A allele might be an important risk factor for IHD. No association between other TNF-α gene polymorphisms and susceptibility to IHD were observed. No publication bias were found. Sensitivity analyses indicated that our results were stable.

CONCLUSION

The present study indicated a possible association between the TNF-α -308G/A gene polymorphism and IHD risk. However, evidence was limited to confirm the role of TNF-α -238G/A, -857C/T, -863C/A, -1031T/C and other TNF-α gene polymorphisms in the risk of IHD.

Associations between the tumor necrosis factor-α gene and interleukin-10 gene polymorphisms and risk of alcoholic liver disease: A meta-analysis

BACKGROUND

The critical roles of tumor necrosis factor-α (TNF-α) and interleukin-10 (IL-10) in the pathogenesis of alcoholic liver diseases (ALD) suggest that functional variations in the TNF-α (TNFA) and IL-10 genes may be related to individual susceptibility to ALD. As available studies examining the associations between TNFA or IL-10 polymorphisms and ALD risk have yielded conflicting results, a meta-analysis was conducted to clarify the potential relation between TNFA and IL-10 polymorphisms and the risk of ALD.

METHODS

A comprehensive literature search was conducted to identify relevant studies. Pooled odds ratios and 95% confidence intervals were calculated using a random-effects model. The heterogeneity between studies was assessed using the Cochran's Q statistic and the I(2) statistic. Publication bias was assessed using funnel plots and the Egger's regression test.

RESULTS

A total of 17studies and 12studies were identified and included in the meta-analysis of the associations between TNFA polymorphisms and ALD risk, and IL-10 polymorphisms and ALD risk, respectively. The pooled results showed that the "A" allele of the TNFA-238G>A polymorphism was significantly associated with an increased risk of ALD. Significant differences in the allele and genotype distributions of the IL-10-1082A>G polymorphism were detected in the comparison between ALD patients and healthy controls, but not when comparing ALD patients and alcohol dependent individuals without ALD. No significant associations between other polymorphic loci and ALD risks were detected.

CONCLUSIONS

The TNFA-238G>A polymorphism was significantly associated with ALD risk, while the TNFA-308G>A polymorphism and IL-10 polymorphisms (-1082A>G and -592C>A) may not be associated with the individual susceptibility to ALD. The impact of combined TNFA and IL-10 polymorphisms on individual susceptibility to ALD needs to be investigated in future studies.

Genetic polymorphisms associated with heart failure: A literature review

Objective

To review possible associations reported between genetic variants and the risk, therapeutic response and prognosis of heart failure.

Methods

Electronic databases (PubMed, Web of Science and CNKI) were systematically searched for relevant papers, published between January 1995 and February 2015.

Results

Eighty-two articles covering 29 genes and 39 polymorphisms were identified.

Conclusion

Genetic association studies of heart failure have been highly controversial. There may be interaction or synergism of several genetic variants that together result in the ultimate pathological phenotype for heart failure.

Association of the -1031T>C polymorphism and soluble TNF-α levels with Acute Coronary Syndrome

INTRODUCTION

Inflammation has gained a pivotal role in the pathophysiology of Acute Coronary Syndrome (ACS). TNF-α is a pro-inflammatory cytokine that could be a potential biomarker in ACS due to its multiple functions. The rs1799964 TNFA polymorphism (-1031T>C) has been associated with a decrease in gene transcription and cytokine levels.

OBJECTIVE

To determine the association of rs1799964 TNFA polymorphism and TNF-α soluble levels in ACS.

METHODS

A total of 251 patients diagnosed with ACS and 164 individuals without cardiovascular diseases classified as the reference group (RG), were included. The rs1799964 polymorphism was genotyped by PCR-RFLP. Soluble protein levels were determined by ELISA. Statistical analyses were performed using chi square and U-Mann Whitney tests.

RESULTS

The genotype and allele frequencies were different between ACS and RG (OR=0.317, p=0.01; OR=0.688, p=0.03 respectively). ACS patients had higher soluble TNF-α levels compared with the RG (31.08 vs 23.00pg/mL, p<0.001); according genotype significant differences were observed (T/T: 24.06 vs T/C: 34.95pg/mL, p=0.0001) in patients. In the RG, T/T carriers showed discrete lower levels than C/C genotype (22.14 vs 27.83pg/mL, p=0.04).

CONCLUSIONS

The -1031C allele of the TNFA polymorphism confers protection for the development of ACS. The T/C genotype carriers had higher TNF-α serum levels compared to the T/T genotype in ACS. In addition, the -1031T>C TNFA polymorphism was associated with dyslipidemia in ACS in a Western Mexican population.

Integrated probability of coronary heart disease subject to the -308 tumor necrosis factor-alpha SNP: a Bayesian meta-analysis

We present a meta-analysis of independent studies on the potential implication in the occurrence of coronary heart disease (CHD) of the single-nucleotide polymorphism (SNP) at the −308 position of the tumor necrosis factor alpha (TNF-alpha) gene. We use Bayesian analysis to integrate independent data sets and to infer statistically robust measurements of correlation. Bayesian hypothesis testing indicates that there is no preference for the hypothesis that the −308 TNF-alpha SNP is related to the occurrence of CHD, in the Caucasian or in the Asian population, over the null hypothesis. As a measure of correlation, we use the probability of occurrence of CHD conditional on the presence of the SNP, derived as the posterior probability of the Bayesian meta-analysis. The conditional probability indicates that CHD is not more likely to occur when the SNP is present, which suggests that the −308 TNF-alpha SNP is not implicated in the occurrence of CHD.

Tumor necrosis factor-alpha G-238A polymorphism and coronary artery disease risk: a meta-analysis of 4,222 patients and 4,832 controls

BACKGROUND

The aim of the present study was to investigate the association between tumor necrosis factor-alpha (TNF-α) gene G-238A polymorphism and risk of coronary artery disease (CAD) using a meta-analytical approach.

METHODS

The PubMed and Embase databases were searched for relevant publications up to January 13, 2015. Four authors (XPH, XDZ, XTZ, and ZJZ) independently selected the studies, extracted, and analyzed the data using the Comprehensive Meta-Analysis software. The sensitivity and subgroups analyses were also performed. Either a fixed effects or a random effects model was used to estimate pooled odds ratios (ORs) and their 95% confidence intervals (CIs).

RESULTS

Finally, ten articles including eleven case-control studies involving 4,222 patients and 4,832 controls were yielded. The results indicated no significant association between G-238A polymorphism and CAD risk (A vs G: OR =1.08, 95% CI =0.89-1.30; AA vs GG: OR =1.15, 95% CI =0.59-2.25; GA vs GG: OR =1.14, 95% CI =0.88-1.48; AA vs [GG + GA]: OR =1.09, 95% CI =0.56-2.14; (GA + AA) vs GG: OR =1.11, 95% CI =0.90-1.38). In the subgroup analyses, similar results were obtained with overall populations. The sensitivity analyses showed that the overall results were robust. No publication bias was detected.

CONCLUSION

Based on current evidence, we can conclude that TNF-α G-238A polymorphism might not be associated with CAD risk.

Intervertebral disc degenerative changes after intradiscal injection of TNF-α in a porcine model

PURPOSE

To investigate whether exogenous tumor necrosis factor-α (TNF-α) will initiate a degenerative process in intervertebral disc in vivo.

METHODS

Exogenous TNF-α in dosages of 50 and 100 ng in 50 μL Dulbecco's Modified Essential Medium (DMEM) was injected into porcine lumbar discs; a third disc was injected only with 50 μL DMEM as a control. Magnetic resonance imaging (MRI) yielding T1- and T2-weighted images, T2-mapping, and post-contrast T1 images was performed and histology was studied as well.

RESULTS

After 3 months, a significant decrease in T2 value calculated from T2-mapping MRI was observed in the annulus and nucleus of both groups injected with TNF-α along with a slight decrease in disc height and nucleus volumes in comparison to the control discs. No obvious visual differences among the groups were observed in the normal T1- and T2-weighted MRI images. Post-contrast T1 MRI showed increased annulus enhancement in both TNF-α-injected groups compared to the control discs, while no enhancement difference was observed in the nucleus. Histological analysis showed degenerative changes with annulus fissure, cell cluster, nucleus matrix loss, vascularization and interleukin-1β expression in the outer annulus of both TNF-α-injected discs, while no degenerative changes were observed in the control discs.

CONCLUSIONS

Intradiscal injection of exogenous TNF-α caused early stage disc degeneration in a porcine model. It may thus support the hypothesis of exogenic TNF-α being an important early pathogenetic factor in disc degeneration.

Tumor necrosis factor-α and its role as a mediator in myocardial infarction: A brief review

Tumor necrosis factor-α (TNF-α) contributes to myocardial infarction (MI) injury. Polymorphism of TNF-α gene promoter region and secretion and release of TNF-α and its transformation by a series of signaling pathways are all changed at different points of pathophysiological process in MI. Researches also investigated TNF-α antagonists and their potential therapeutic role in the setting of MI and heart failure at both molecular and clinical level. This article briefly reviews TNF-α and its mechanism as a mediator in MI.

Influence of tumor necrosis factor alpha gene promoter polymorphisms and its serum level on migraine susceptibility in Egyptian patients

BACKGROUND

Migraine is a common chronic neurological disorder with still largely unknown pathogenesis. We aimed to explore the possible role of tumor necrosis factor alpha (TNF-α) gene polymorphisms as risk factors of migraine, and whether they influence the TNF-α level.

MATERIALS AND METHODS

Two hundred patients with migraine and 200 controls were enrolled in this study. Polymorphisms of TNF-α gene were detected using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Serum TNF-α level was measured using enzyme-linked immunosorbent assay (ELISA).

RESULTS

TNF-α-308 GA, AA genotypes and A allele, TNF-α-857 CT genotype and T allele were associated with increased risk of migraine, while the TNF-α-238 polymorphism was not. TNF-α-308 GA, AA genotypes and A allele or AA genotype were associated with increased risk of migraine with aura (MA) and migraine without aura (MO) respectively; this was more significant in female patients with MA than in males. TNF-α-857 CT genotype was associated with increased risk of MO, or MA in females or males. While -857T allele was significantly associated with MO or MA in males and with MA only in females. On the other hand, we didn't find any significant associations of TNF-α-238 polymorphism with MO, or MA in males or females. TNF-α levels were higher in patients with migraine, MA, or MO than in controls (P<0.001).

CONCLUSION

TNF-α polymorphisms were associated with migraine, MA, or MO in Egyptians.

Helicobacter pylori-an infectious risk factor for atherosclerosis?

Accumulating evidence implicates Helicobacter pylori (H. pylori) infection in the pathogenesis of certain diseases localized outside the stomach, particularly those characterized by persistent and low-grade systematic inflammation. Recently, the role of H. pylori infection in the development of atherosclerosis and its clinical complications has received attention. Atherosclerosis is a high-cost disease, and acute events resulting from this condition rank first among morbidity and mortality statistics in most industrialized countries. Atherosclerosis is a multifactorial disorder, and traditional risk factors explain only 50% of its etiology. Therefore, identifying new risk factors for atherosclerosis is necessary. Serological studies indicate that chronic H. pylori infection, especially that with more virulent strains, may predispose patients to the onset of atherosclerosis and related adverse clinical events, and PCR studies have detected H. pylori DNA in atherosclerotic plaques, although this finding remains controversial. If this association were to be confirmed, its importance to public health would be substantial, as the eradication of H. pylori is more straightforward and less costly than the long-term treatment of other risk factors. This review investigates the potential relationship between H. pylori infection and atherosclerosis from both epidemiological and pathogenic perspectives and characterizes the potential mechanisms underlying this correlation.

Relationship between periodontitis and cardiovascular diseases: A literature review

Periodontitis and cardiovascular disease have a complex etiology and genetics and share some common risk factors (i.e., smoking, age, diabetes, etc.). In recent years, the relationship between periodontal disease and cardiovascular disease has been investigated extensively. This research mostly focused on the fact that periodontitis is an independent risk factor for cardiovascular disease. Our aim in this article is to investigate the etiological relationship between periodontal disease and cardiovascular disease and the mechanisms involved in this association. According to the current literature, it is concluded that there is a strong relationship between these chronic disorders.

Association of interleukin 8 with myocardial infarction: results from the Stockholm Heart Epidemiology Program

BACKGROUND

Interleukin 8 (IL8) has been contradictorily associated with the risk of myocardial infarction (MI).

AIM

To investigate the association of IL8 serum levels with the risk of MI and the association of the IL8 (IL8) and IL8 receptors (CXCR1 and CXCR2) genetic variants with IL8 levels and MI risk in a large case control study, the Stockholm Heart Epidemiology Program.

METHODS AND RESULTS

IL8 levels (pg/mL) were divided into quartiles and the MI risk was calculated by logistic regression and expressed as odds ratio (OR) and 95% CI. Two IL8 SNPs (rs4073A/T, rs2227306C/T) and three SNPs tagging CXCR1 and CXCR2 (rs4674258C/T, rs1008563C/T, rs6723449T/C) were analyzed for association with IL8 levels and with MI risk. Multivariate adjusted ORs for MI risk by IL8 levels in the highest quartiles indicated reduced point estimates in both women (OR 0.37; 95% CI 0.2-0.8) and men when compared to the lowest quartile. In female cases, IL8 levels decreased progressively in the six months after MI (p=0.03). IL8, CXCR1 and CXCR2 genetic variants were not associated with IL8 levels. In men, the T allele at the IL8 SNP rs4073 was associated with a slight increase in the MI risk under an additive and a recessive model of inheritance.

CONCLUSIONS

IL8 serum levels were associated with a reduced occurrence of MI among women, whereas IL8 was associated with a slightly increased risk among men, possibly through different mechanisms. These data suggest that the biological effects of IL8 on MI risk may vary over time and warrant further cohort studies with repetitive IL8 measurements.

Association of inflammatory cytokines and endothelial adhesion molecules with immunological, virological, and cardiometabolic disease in HIV-infected individuals

Elevated levels of inflammatory and endothelial biomarkers are related to chronic diseases, cancers, and cardiovascular disease. This study aimed at evaluating the association of inflammatory cytokines and endothelial adhesion molecules with immunological, virological, and cardiometabolic disease in HIV-infected individuals. A cross-sectional study was initiated to evaluate the association of CD4 lymphocyte count, viral load, antiretroviral therapy, and metabolic and cardiovascular disease with inflammatory cytokines [interleukin (IL)-1β, IL-6, and tumor necrosis factor α (TNF-α)], adhesion molecules [soluble intercellular Adhesion Molecule 1 (sICAM) and soluble Vascular Adhesion Molecule 1 (sVCAM)], and highsensitive C-reactive protein (hs-CRP) levels in 125 HIV-infected patients. The associations between independent variables and biomarkers were analyzed by means of multivariate logistic regression. A viral load ≥100,000 copies/mL had a stronger association with high levels of sVCAM-1 (P=0.026; OR=2.54; CI=1.12-5.78) and TNF-α (P=0.048; OR=2.42; CI=1.01-5.85) than the current viral load using a multivariate analysis. Antiretroviral treatment was associated with lower levels of sVCAM-1 (P=0.20; OR=0.20; CI=0.05-0.78), TNF-α (P=0.060; OR=0.22; CI=0.05-1.07), and hs-CRP (P=0.093; OR=0.44; CI=0.17-1.15). CD4 counts <200 cells/mm(3) were associated with high IL-6 levels (P=0.013; OR=3.17; CI=1.27-7.91); however, antiretroviral treatment was not associated with IL-6 levels. Metabolic syndrome was associated with high hs-CRP levels, systolic hypertension was associated with IL-6 levels, and family history of coronary disease was associated with TNF-α levels. High biomarker levels were associated not only with viral and immunological characteristics but also with cardiometabolic factors. The maximum viral load attained was an important risk factor for high levels of TNF-α and sVCAM-1. Treatment protected patients from high biomarker levels, except IL-6.

Tumor necrosis factor-alpha gene promoter region polymorphism and the risk of coronary heart disease

BACKGROUND

Tumor necrosis factor-alpha (TNF- α ) gene polymorphisms have been implicated in the manifestation of atherosclerosis. Controversy exists regarding the link between the cytokine's variant genotype and CHD among different ethnic groups. There have been fewer studies on the TNF- α gene -1031T>C and -863C>A polymorphisms in relation to CHD. Therefore, the current study was designed to investigate the association of the TNF- α gene -1031T>C and -863C>A polymorphisms with CHD in a Pakistani population.

METHODS

Patients with CHD (n = 310) and healthy individuals (n = 310) were enrolled in this study. Genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP).

RESULTS

A significant difference was observed in the -863C>A polymorphism between patients with CHD and control subjects (P < 0.0001). CHD risk was positively associated with the variant allele -863A (P < 0.0001) in the study subjects. There was no significant link between the -1031T>C polymorphism and CHD risk in the study population. Haplotypes A-T and A-C of the TNF-alpha gene loci at -863 and -1031 showed higher frequency in the patient group compared with controls (P < 0.05).

CONCLUSION

The TNF- α   -863C>A gene polymorphism was associated with the pathogenesis of CHD while the -1031T>C polymorphism did not show any link with the disease in a Pakistani population.

Interaction between air pollution exposure and genes in relation to levels of inflammatory markers and risk of myocardial infarction

OBJECTIVES

Air pollution exposure induces cardiovascular effects, possibly via systemic inflammation and coagulation misbalance. Genetic variation may determine individual susceptibility. Our aim was to investigate effect modification by inflammation (Interleukin6 (IL6), tumour necrosis factor-α (TNF-α)) and coagulation (fibrinogen Bβ, plasminogen activator inhibitor-1 (PAI-1)) gene variants on the effect of long-term or short-term air pollution exposure on both blood marker levels and non-fatal myocardial infarction (MI) risk.

DESIGN

Population-based case-control study with a nested case-crossover study. Gene-environment interactions for short-term and long-term air pollution on blood marker levels were studied in population controls, for long-term exposure on MI risk using case-control design, and for short-term exposure on MI onset using case-crossover design.

SETTING

The Stockholm Heart Epidemiology Programme (SHEEP) conducted in 1992-1994 in Stockholm, Sweden. Spatial modelling was used to assess long-term (up to 30 years retrospectively) air pollution exposure to traffic-NO2 and heating-SO2 emissions at home addresses. Urban background NO2, SO2, PM10 and O3 measurements were used to estimate short-term (up to 5 days) air pollution exposure.

PARTICIPANTS

1192 MI cases and 1506 population controls aged 45-70 years.

OUTCOMES

The levels of blood markers of inflammation (IL-6, TNF-α) and coagulation (fibrinogen, PAI-1) and MI risk.

RESULTS

We observed gene-environment interaction for several IL6 and TNF SNPs in relation to inflammation blood marker levels. One-year traffic-NO2 exposure was associated with higher IL-6 levels with each additional IL6-174C allele, and 1-year heating-SO2 exposure with higher levels of TNF-α in TNF-308AA homozygotes versus -308G carriers. Short-term air pollution exposure also interacted with IL6 and TNF in relation to marker levels. The risk of MI followed the effect on blood markers in each genotype group.

CONCLUSIONS

Genetic variants in IL6 and TNF may modify effects of long-term and short-term air pollution exposure on inflammatory marker levels and MI risk.

Plasma TNF-α levels are higher in early pregnancy in patients with secondary compared with primary recurrent miscarriage

PROBLEM

Specific pro-inflammatory cytokine profiles in plasma may characterize women with recurrent miscarriage (RM) but the dynamics of the cytokine profiles with progressing pregnancy is largely unknown.

METHOD OF STUDY

Plasma was repeatedly sampled in the first trimester from 47 RM patients. The concentrations of five cytokines including tumour necrosis factor alpha (TNF-α) were measured. TNF-α levels were correlated to carriage of five TNFA promoter polymorphisms.

RESULTS

TNF-α levels increased (P = 0.014) with progressing pregnancy, with higher levels in secondary than primary RM (P = 0.042) but with no significant impact on outcome. Carriage of TNFA -863C and TNFA -1031T was associated with higher TNF-α levels, and the former was found more often in secondary than primary RM (P < 0.02).

CONCLUSION

Plasma TNF-α levels increase during early pregnancy in RM women regardless of outcome, but are higher in secondary than primary RM, which may be partly genetically determined.

Linking preeclampsia and cardiovascular disease later in life

Preeclampsia (PE), which is defined as new onset hypertension after 20 weeks of pregnancy accompanied by proteinuria, is characterized by inadequate placentation, oxidative stress, inflammation and widespread endothelial dysfunction. A link between PE and long-term risk of cardiovascular disease (CVD) was suggested by retrospective studies, which found that PE was associated with a 2–3-fold risk of CVD later in life, with a 5–7-fold risk in the case of severe and/or early-onset PE. Recently, meta-analyses and prospective studies have confirmed the association between PE and the emergence of an unfavorable CVD risk profile, in particular a 3–5-fold increased prevalence of the metabolic syndrome only 8 years after the index pregnancy. PE and CVD share many risk factors, including obesity, hypertension, dyslipidemia, hypercoagulability, insulin resistance and both entities are characterized by endothelial dysfunction. PE and CVD are complex traits sharing common risk factors and pathophysiological processes, but the genetic link between both remains to be elucidated. However, recent evidence suggests that genetic determinants associated with the metabolic syndrome, inflammation and subsequent endothelial dysfunction are involved. As the evidence now supports that PE represents a risk factor for the emergence of the metabolic syndrome and CVD later in life, the importance of long-term follow-up assessment of CVD risk beginning early in women with a history of PE must be considered and translated into new preventive measures.

Tumor necrosis factor-alpha G-308 A polymorphism and risk of coronary heart disease and myocardial infarction: A case-control study and meta-analysis

Objectives:

The tumor necrosis factor-alpha (TNF-α) gene may play an important role in coronary heart disease (CHD) and myocardial infarction (MI) risk. Recently, controversial results regarding the association of the G-308 A (rs1800629)polymorphism of the TNF-α gene with CHD/MI have been reported. We herein examine a possible association between the G-308 A (rs1800629)polymorphism of the TNF-α gene and CHD/MI in a sample of the Chinese Han population.

Materials and Methods:

We determined the genotypes of TNF-α G-308 A (rs1800629) in 535 unrelated Chinese patients with CHD, 420 patients with MI, and 1020 coronary artery disease-free controls. Additionally, a meta-analysis of all previous studies on the TNF-α G-308 A polymorphism and the risk of CHD and MI was performed.

Results:

AA genotypes in the G-308 A (rs1800629)polymorphism of the TNF-α gene did not occur more frequently in CHD/MI patients than in controls; odds ratios (95% confidence intervals) were 1.743 (0.325 to 1.423) for CHD and 1.731 (0.442 to 1.526) for MI, after adjusting for conventional risk factors. Further stratification for age, gender, and other cardiovascular risk factors did not alter the prior negative findings. Pooled meta-analysis of 23 studies also found no statistically significant associations between the TNF-α polymorphism and CHD/MI risk in the genetic additive, dominant, and recessive models. Subgroup analyses showed no association between the TNF-α polymorphism and CHD/MI in Asian and Caucasian populations.

Conclusion:

Our study showed no association between the G-308 A (rs1800629) polymorphism of the TNF-α gene (presence of A allele) and CHD/MI in the Chinese Han population. There was no evidence of a difference in risk effects of rs1800629 between Caucasians and Asians.

Risk of glycemic disorder in elderly women adjusted by anthropometric parameters and cytokine genotypes

OBJECTIVE

The objective of the present study was to examine the association of glucose intolerance and type-2 diabetes mellitus with the -174 G > C and -308 G > A allelic variations of IL-6 and TNF-α, respectively, through anthropometric measurements and age strata.

METHODS

This is a cross-sectional study using data from 285 community dwelling elderly women who underwent physical, biochemical, and genetic examinations.

RESULT

Genotype-unadjusted analysis revealed that the risk of glucose intolerance and diabetes in elderly women with elevated BMI was 1.71 and 2.82 times higher, respectively, whereas age and conicity index did not show predictive value. Prevalence ratios for glucose intolerance and diabetes across allelic variants of IL-6 and TNF-α did not associate IL-6 with unbalanced glucose levels, despite adjustment for BMI, age, and conicity index. Conversely, carriers of the TNF-α A allele were 2.06 and 5.58 times more likely to exhibit glucose intolerance and diabetes, respectively, compared to GG homozygotes.

CONCLUSION

Our results suggest that bearing the A allele of the -308 G > A polymorphism of TNF-α predisposes to anthropometric measure-sensitive impaired glucose metabolism in older women.

The role of tumour necrosis factor-α and tumour necrosis factor receptor signalling in inflammation-associated systemic genotoxicity

Chronic inflammatory diseases are characterised by systemically elevated levels of tumour necrosis factor (TNF)-α, a proinflammatory cytokine with pleiotropic downstream effects. We have previously demonstrated increased genotoxicity in peripheral leukocytes and various tissues in models of intestinal inflammation. In the present study, we asked whether TNF-α is sufficient to induce DNA damage systemically, as observed in intestinal inflammation, and whether tumour necrosis factor receptor (TNFR) signalling would be necessary for the resultant genotoxicity. In the wild-type mice, 500 ng per mouse of TNF-α was sufficient to induce DNA damage to multiple cell types and organs 1-h post-administration. Primary splenic T cells manifested TNF-α-induced DNA damage in the absence of other cell types. Furthermore, TNFR1(-/-)TNFR2(-/-) mice demonstrated decreased systemic DNA damage in a model of intestinal inflammation and after TNF-α injection versus wild-type mice, indicating the necessity of TNFR signalling. Nuclear factor (NF)-κB inhibitors were also able to decrease damage induced by TNF-α injection in wild-type mice. When TNF-α administration was combined with interleukin (IL)-1β, another proinflammatory cytokine, DNA damage persisted for up to 24 h. When combined with IL-10, an anti-inflammatory cytokine, decreased genotoxicity was observed in vivo and in vitro. TNF-α/TNFR-mediated signalling is therefore sufficient and plays a large role in mediating DNA damage to various cell types, subject to modulation by other cytokines and their mediators.

Association of tumor necrosis factor-α (TNF-α) promoter polymorphisms with overweight/obesity in a Korean population

OBJECTIVE

Obesity is characterized by the activation of an inflammatory process leading to an increase in proinflammatory cytokines and adipokines. This study was designed to investigate the genetic association between tumor necrosis factor-α (TNF-α) polymorphisms and the risk of obesity in the Korean population.

METHODS

Three single nucleotide polymorphisms [G-238A (rs361525), C-857T (rs1799724), and C-863A (rs1800630)] in the promoter region of TNF-α gene were analyzed in 123 control [body mass index (BMI) between 18 and 23] and 208 overweight/obese (BMI ≥ 23) subjects.

RESULTS

The mean values of BMI in the control and overweight/obese groups were 21.1 ± 1.4 and 25.4 ± 1.8, respectively. Of the three SNPs, G-238A presented a significant association with overweight/obesity in the codominant model; the frequency of the G/G genotype in the overweight/obese group was 9.3% higher than that in the control group (P = 0.0046). When control and overweight/obesity subjects were combined together and analyzed, the level of high-density lipoprotein (HDL) was significantly higher in the C-857T C/C type SNP (P < 0.05).

CONCLUSIONS

The results of this study suggest that the G allele of G-238A in TNF-α gene may be a risk factor for overweight/obesity in the Korean population and that the C allele of C-857T may be an protective factor in relation to the HDL level in the general Korean population.

Association of TNF-alpha genetic polymorphisms with hepatocellular carcinoma susceptibility: a case-control study in a Han Chinese population

The single nucleotide polymorphisms (SNPs) within the tumor necrosis factor-a (TNF-a) gene promoter region have been reported to be associated with susceptibility to various types of cancers. A case-control study (126 hepatocellular carcinoma [HCC] patients and 126 normal controls) was conducted to elucidate their possible association with the risk of hepatitis B virus (HBV)-related HCC in a Han Chinese population. TNF-alpha polymorphisms -1031T/C, -863C/A, -857C/T, -308G/A, and -238G/A were genotyped by polymerase chain reaction (PCR) and direct DNA sequencing. Disease associations were analyzed by the chi-square test or Fisher's exact test. When analyzed by overall groups, no significant differences in genotype and allele distributions were observed between the control and cases. However, stratified analysis according to sex showed that the frequency of the homozygous C allele of the -857 polymorphism was lower in female cases than in female controls (62.9% vs. 88.9%, p=0.026). In addition, further haplotype analysis revealed that the TCCGA (-1031/-863/-857/-308/-238) was more frequent in controls than cases (p=0.018; odds ratio = 0.266; 95% confidence interval, 0.083-0.857). These results indicated that the TNF-alpha-857C/T polymorphism may modify HBV-related HCC risk among women, and the haplotype TCCGA (-1031/-863/-857/-308/-238) may account for a decreased susceptibility to HCC development in the Han Chinese population. Additional studies in patients with different ethnic backgrounds are needed to validate these finding and to further explore the genetic pathogenesis of HBV-related HCC.

TNFA -308 (rs1800629) polymorphism is associated with a higher risk of cardiovascular disease in patients with rheumatoid arthritis

OBJECTIVE

To assess the influence of the TNFA rs1800629 (G > A) polymorphism in the risk of cardiovascular (CV) disease and subclinical atherosclerosis in patients with rheumatoid arthritis (RA).

METHODS

587 patients fulfilling the 1987 American College of Rheumatology classification criteria for RA were studied. Patients were genotyped for the TNFA rs1800629 polymorphism using predesigned TaqMan single nucleotide polymorphism genotyping assay. Also, HLA-DRB1 genotyping was performed using molecular based methods. Carotid artery intima-media thickness, flow-mediated endothelium-dependent and endothelium independent vasodilatation, used as surrogate markers of subclinical atherosclerosis, were measured in a subgroup of patients.

RESULTS

We observed a higher frequency of carriers of the minor allele A among the patients with CV disease (with 37.6% vs. without 27.9%, p = 0.06, OR 1.56 [95% confidence interval-CI 0.95-2.54]). Carriers of the minor allele A exhibited a higher risk of CV events after adjustment for demographic and traditional CV risk factors (p = 0.023, HR 1.72 [95% CI 1.076-2.74]). Also, a significant interaction between this polymorphism and the presence of the rheumatoid shared epitope (SE) was observed (p = 0.024). Due to this, the association between carriers of the minor allele A and CV disease was only present in carriers of the SE, even after adjustment (p = 0.001, HR 2.43 [95% CI 1.41-4.19]). No significant association between the TNFA variant and the surrogate markers of subclinical atherosclerosis was observed.

CONCLUSION

Our results show that TNFA rs1800629 gene polymorphism is associated with predisposition to CV complications in patients with RA. This predisposition is restricted to individuals carrying the rheumatoid SE.

Tumor necrosis factor-alpha G-308A gene polymorphism and coronary heart disease susceptibility: an updated meta-analysis

PURPOSE

Several studies have reported apparently conflicting findings for the effects of tumor necrosis factor-alpha (TNF-α) G-308A polymorphism on coronary heart disease (CHD) susceptibility. We undertook a systematic review and meta-analysis to investigate the association between this gene variant and CHD predisposition.

METHODS

We systematically searched electronic databases (Medline, EMbase, Chinese BioMedical, BIOSIS, Global Health, PsycINFO, Allied and Complementary Medicine Database, Cochrane Library, HuGE Navigator, and British Nursing) for relevant studies published between 1947 and October, 2010. Summarized estimation of odds ratio (OR) and 95% confidence interval (CI) were calculated. Publication bias and heterogeneity among studies were explored.

RESULTS

We identified 24 studies providing data for 9 921 cases and 7 944 controls. Pooled analysis based on ORs adjusted by CHD risk factors showed that carrying the TNF-α gene A variant conferred a 1.5-fold increased risk of developing CHD (AG+AA vs. GG, OR = 1.50, 95% CI: 1.23-1.77) in Caucasian population. No significant association between the gene polymorphism and CHD risk could be found in other ethnic groups.

CONCLUSIONS

It is probable that carrying the A variant is associated with CHD risk in Caucasians but not in Asians, Indians, or Africans. Further studies are merited to assess the association in greater details, especially in Asians, Indians and Africans.

NADPH oxidases regulate CD44 and hyaluronic acid expression in thrombin-treated vascular smooth muscle cells and in atherosclerosis

The intracellular signaling events by which NADPH oxidase-generated reactive oxygen species (ROS) modulate vascular smooth muscle cell (VSMC) function and atherogenesis are yet to be entirely elucidated. We previously demonstrated that NADPH oxidase deficiency decreased atherosclerosis in apoE(-/-) mice and identified adhesion protein CD44 as an important ROS-sensitive gene expressed in VSMC and atherosclerotic lesions. Here, we examined the molecular mechanisms by which NADPH oxidase-generated ROS regulate the expression of CD44 and its principal ligand, hyaluronan (HA), and how CD44-HA interaction affects VSMC proliferation and migration and inflammatory gene expression in apoE(-/-) mice aortas. Thrombin-induced CD44 expression is mediated by transcription factor AP-1 in a NADPH oxidase-dependent manner. NADPH oxidase-mediated ROS generation enhanced thrombin-induced HA synthesis, and hyaluronan synthase 2 expression in VSMC. Hyaluronidase, which generates low molecular weight HA (LMW-HA), is induced in VSMC in a NADPH oxidase-dependent manner and LMW-HA stimulated ROS generation and cell proliferation in wild-type but not p47(phox-/-) VSMC, effects that were enhanced by thrombin pretreatment. Haptotactic VSMC migration toward HA was increased by thrombin in a CD44-dependent manner. HA expression in atherosclerotic lesions and plasma-soluble CD44 and HA levels were higher in apoE(-/-) compared with apoE(-/-)/p47(phox-/-) mice. HA-regulated pro-inflammatory gene expression was higher in apoE(-/-) than apoE(-/-)/p47(phox-/-) mouse aortas. GKT136901, a specific inhibitor of Nox1- and Nox4-containing NADPH oxidase activity, attenuated ROS generation and atherosclerosis and decreased CD44 and HA expression in atherosclerotic lesions. Together, these data suggest that increased CD44 and HA expression and CD44-HA-dependent gene regulation may play a role in atherosclerosis stimulated by NADPH oxidase activation.

Serum and gene expression profile of tumor necrosis factor-alpha and interleukin-6 in hypertensive diabetic patients: effect of amlodipine administration

Pro-inflammatory cytokines are critical factors in type 2 diabetes-associated atherosclerosis. We aim to analyze in hypertensive type 2 diabetic patients the serum concentrations and the mRNA expression levels in peripheral blood mononuclear cells (PBMC) of the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6), as well as to evaluate the effect of amlodipine administration. Twenty-one hypertensive diabetic patients and 10 healthy non-diabetic controls were included in the study. Serum levels of cytokines were measured by chemiluminescent immunometric assay, and mRNA expression levels by RT-PCR. The mean serum concentrations of TNF-alpha and IL-6 in diabetic patients showed a 6.1-fold and 2.9-fold increase with respect to non-diabetic control subjects, respectively (p less than 0.0001). Likewise, there was a 3.3- and a 4-fold increase in the PBMC mRNA expression level of TNF-alpha and IL-6 (p less than 0.0001) in diabetic subjects. After amlodipine administration, a significant decrease (p less than 0.01) was observed in the serum TNF-alpha and IL-6 levels. In addition, pre-treatment mRNA expression of TNF-alpha and IL-6 also decreased, with a mean percent reduction of 26 percent (p less than0.01) and 25 percent (p less than 0.001), respectively. In conclusion, serum concentrations and PBMC mRNA expression levels of TNF-alpha and IL-6 are significantly elevated in hypertensive type 2 diabetic patients. Administration of amlodipine is associated with a significant reduction of the increased levels of these inflammatory parameters, both at the protein as well as at the transcriptional level. These modulatory effects of amlodipine on proinflammatory cytokine level and expression may be related to its suggested anti-atherosclerotic actions.

-308G>A and -1031T>C tumor necrosis factor gene polymorphisms in Tunisian patients with coronary artery disease

BACKGROUND

Recent research has shown that inflammation plays a key role in coronary artery disease (CAD) and other manifestations of atherosclerosis. Several lines of evidence support a key role for tumor necrosis factor-alpha (TNF-alpha), a potent immunomodulator and pro-inflammatory cytokine, in the development of atherosclerosis and in complications of CAD.

METHODS

We investigated the possible association between CAD and the TNF gene promoter polymorphisms -308G>A and -1031T>C in a Tunisian population. We compared the distribution of these polymorphisms between 418 patients with CAD and 406 healthy controls using polymerase chain reaction restriction fragment length-polymorphism analysis.

RESULTS

The frequency of the TNF-alpha -308A allele in the control group was similar to that observed in CAD patients [p=0.78; odds ratio (OR)=1.15; 95% confidence interval (CI)=0.86-1.55], but higher than those described in other Europeans, such as in the French, Finnish and Spanish. Concerning the TNF-alpha -1031T/C polymorphism, the same distribution was observed between patients with CAD and controls (p=0.12; OR=1.27; 95% CI=0.94-1.72). In addition, the genotype and allele frequencies of control individuals were comparable to those previously reported in healthy Tunisian controls and other ethnic groups. Haplotype analysis (TNF-alpha -308G>A and -1031T>C) demonstrated no significant association between TNF haplotypes and CAD.

CONCLUSIONS

We conclude that TNF promoter gene polymorphisms at position -308G>A and -1031T>C do not play a major role in the pathogenesis of CAD in the Tunisian population.

IL-10 and TNF-α promoter haplotypes are associated with childhood Crohn’s disease location

AIM: To determine the distribution and frequencies of the genotypes and haplotypes of the genes encoding for the glucocorticoid receptor (GR), the tumor necrosis factor (TNF)-α and the interleukin (IL)-10 in childhood Crohn’s disease (CD) and to assess the impact of the corresponding DNA variants on clinical and disease phenotypes.

METHODS: Ten variants in GR, TNF-α and IL-10 were genotyped in 113 childhood CD cases and 95 healthy subjects, both of French-Canadian origin.

RESULTS: For the GR polymorphisms (R23K and N363S) and IL-10 variants in the 5’flanking region (-1082 G > A, -819 T > C and -592 A > C), no difference was observed in allele and genotype frequencies between CD patients and controls. At the haplotype level, we found three IL-10 haplotypes previously described in Caucasians (GCC, ACC and ATA) and three novel haplotypes only present in IBD patients. When we analyzed the haplotype distribution with the anatomical location of the disease, the GCC haplotype was associated with the colonic and the ACC haplotype with the terminal ileum location, respectively. The genotyping of five polymorphisms in the promoter region of the TNF-α gene (-1031 T > C, -863 A > C, -857 T > C, -308 A > G and -238 A > G) revealed a significant overrepresentation of homozygous -1031 CC among CD patients (OR = 9.9) and an association with the colonic location. For TNF-α, eleven haplotypes were inferred, including two frequent ones, TCCGG and CACGG, which were significantly observed more frequently in controls and cases, respectively.

CONCLUSION: This is one of the first studies investigating the association between haplotype structure and disease location in a CD pediatric cohort. Our results will help to increase our understanding of the genetic determinants of childhood CD.

The role of TNF genetic variants and the interaction with cigarette smoking for gastric cancer risk: a nested case-control study

BACKGROUND

The aim of this study was to investigate the role of TNF genetic variants and the combined effect between TNF gene and cigarette smoking in the development of gastric cancer in the Korean population.

METHODS

We selected 84 incident gastric cancer cases and 336 matched controls nested within the Korean Multi-Center Cancer Cohort. Six SNPs on the TNF gene, TNF-alpha-238 G/A, -308 G/A, -857 C/T, -863 C/A, -1031 T/C, and TNF-beta 252 A/G were genotyped. The ORs (95% CIs) were calculated using unconditional logistic regression model to detect each SNP and haplotype-pair effects for gastric cancer. The combined effects between the TNF gene and smoking on gastric cancer risk were also evaluated. Multi dimensionality reduction (MDR) analyses were performed to explore the potential TNF gene-gene interactions.

RESULTS

TNF-alpha-857 C/T containing the T allele was significantly associated with an increased risk of gastric cancer and a linear trend effect was observed in the additive model (OR = 1.6, 95% CI 1.0-2.5 for CT genotype; OR = 2.6, 95% CI 1.0-6.4 for TT genotype). All haplotype-pairs that contained TCT or CCC of TNF-alpha-1031 T/C, TNF-alpha-863 C/A, and TNF-alpha-857 C/T were associated with a significantly higher risk for gastric cancer only among smokers. In the MDR analysis, regardless of smoking status, TNF-alpha-857 C/T was included in the first list of SNPs with a significant main effect.

CONCLUSION

TNF-alpha-857 C/T polymorphism may play an independent role in gastric carcinogenesis and the risk for gastric cancer by TNF genetic effect is pronounced by cigarette smoking.

Impulsive-disinhibited personality and serotonin transporter gene polymorphisms: association study in an inmate's sample

The association between different impulsive-disinhibited personality traits with 5-HTTLPR and 5-HTTVNTR genetic polymorphisms was examined in an imprisoned male sample. Higher scores of the impulsive-disinhibited personality traits tended to be associated with carrying one or two copies of the 5-HTTPLR S allele (S/S homozygous and S/L heterozygous), and carrying two copies of the 5-HTTVNTR 12 allele (12/12 homozygous). Genotype, allele, haplotype and extended genotype distribution between low and high impulsive-disinhibited groups confirmed this association. Allele S and genotypes S/S+S/L at the 5-HTTLPR locus and allele 12 and genotype 12/12 at the 5-HTTVNTR locus were overrepresented in the high scoring group. Accordingly, allele S and allele 12 conferred a trend for risk to be in the high scoring group with an odds ratio (OR) of 1.8 (p < 0.035) and 1.7 (p < 0.014), respectively. In addition, extended genotype distribution shows that those S allele carriers (S/S homozygote and S/L heterozygote) that were also 12/12 homozygote, were overrepresented in the high scoring group (OR = 3.2; p < 0.004). The main risk of being in the high scoring group was assigned to those carrying two copies of the S-12 haplotype (OR = 5.7; p < 0.0007). We discuss the possible relationship between the two genetic serotonin polymorphisms and the personality impulsive-disinhibited traits investigated.