Tumor necrosis factor-alpha -308 promoter gene polymorphism and increased tumor necrosis factor serum bioactivity in farmer's lung patients

Hypersensitivity pneumonitis (HP) represents an immunologic reaction of the pulmonary parenchyma to an inhaled agent. Since tumor necrosis factor (TNF)-alpha is thought to be involved in the pathogenesis of HP, and polymorphisms in the TNF genes have been associated with variations in the production of TNF-alpha, we investigated the serum bioactivity and genotype of TNF in HP. TNF bioactivity was measured after hay dust challenge in eight patients with farmer's lung (Group A) and in 12 healthy, sensitized (antibody-positive) controls (Group B). Genotyping for the -308 TNF-alpha promoter polymorphism and the TNF-beta intron 1 gene polymorphism was performed in 20 patients with farmer's lung, 25 patients with pigeon breeder's lung, and 216 controls. TNF bioactivity increased in Group A at 4 to 10 h after hay dust challenge, but not in Group B (p < 0.05). The frequency for the TNFA2 allele, a genotype associated with high TNF-alpha production in vitro, was significantly higher in farmer's lung patients (frequency [f] = 0.43, p = 0.0012) than in controls (f = 0.19) or patients with pigeon breeder's lung (f = 0.16). Genotyping for TNF-beta revealed no significant abnormalities. Thus, increased production of TNF-alpha after hay contact, and a genetic predisposition to TNF-alpha production, are implicated in the pathogenesis of alveolitis in farmer's lung.     

Relationship of the tumor necrosis factor-alpha -308 A/G promoter polymorphism with insulin sensitivity and abdominal fat distribution in Japanese patients with type 2 diabetes mellitus

We investigated the relationship of the A/G variant of the tumor necrosis factor-alpha (TNF-alpha) gene promoter at position -308 with insulin resistance and abdominal fat distribution in type 2 diabetic patients in the Japanese population. The TNF-alpha polymorphism was evaluated by polymerase chain reaction-restriction fragment length polymorphism in 142 healthy volunteers and 132 type 2 diabetic patients. Insulin sensitivity was assessed by homeostasis model assessment (HOMA) index in healthy subjects and hyperinsulinemic euglycemic clamp in type 2 diabetic patients. Abdominal fat distribution was evaluated by computed tomography (CT) scanning in diabetic patients. The TNF-alpha polymorphism was detected in three healthy volunteers and three type 2 diabetic patients, all of them being heterozygotes. There was no significant difference in allele frequencies of the -308 polymorphism between healthy subjects (0.0106) and type 2 diabetic patients (0.0114). HOMA index was no significant difference between healthy subjects with and without polymorphism (1.09 +/- 0.03 vs. 1.02 +/- 0.05). Glucose infusion rate (GIR), an index of insulin sensitivity, was not significantly different between diabetic patients with and without TNF-alpha polymorphism (40.4 +/- 4.1 vs. 45.0 +/- 1.8 micromol/kg per min). Moreover, no remarkable effect of TNF-alpha polymorphism on abdominal fat distribution was observed in diabetic patients. These results suggest that A/G heterozygotes of the TNF-alpha gene promoter at position -308 play no major role in the pathogenesis of insulin resistance or abdominal fat distribution in Japanese type 2 diabetic patients.     

The G-308A promoter variant of the tumor necrosis factor-alpha gene is associated with hypertension in adolescents harboring the metabolic syndrome

BACKGROUND: Tumor necrosis factor-alpha (TNF-alpha) has been associated with obesity, obesity-related hypertension, and metabolic syndrome. We investigated the possible contribution of the G-308A TNF-alpha mutant to explain variables of the metabolic syndrome. METHODS: Data and blood samples were used from the 175 adolescents that satisfied the criterion of having systolic or diastolic blood pressures (BP) more than the 80th or less than the 20th percentiles, out of a cross-sectional, population-based study of 934 high school students. Genotyping for the polymorphism was performed by polymerase chain reaction-based restriction fragment length polymorphism analysis. RESULTS: In univariate analysis, we found that there was no difference between A allele carriers and noncarriers in most of the clinical characteristics of the metabolic syndrome such as body mass index (BMI), waist-to-hip ratio, plasma leptin levels, total cholesterol, HDL- and LDL-cholesterol, triglycerides, plasma fasting glucose, insulin, and homocysteine levels. However, we found a significantly (P = .015) higher age- and sex-adjusted systolic BP (Z score) in the A allele carriers, and A allele carriers also showed an elevated homeostasis model assessment of insulin resistance (HOMA) index with respect to noncarriers. Logistic regression analysis indicates that A allele carriers had a 2.8-fold higher probability of being hypertensive independent of BMI, waist-to-hip ratio, and HOMA index. CONCLUSIONS: In this report we found a positive association between the G-308A TNF-alpha variant and systolic arterial BP Z score and HOMA index in adolescents harboring features of metabolic syndrome. Therefore, the A allele may predispose to hypertension and insulin resistance in youth.     

Tumor necrosis factor-alpha gene promoter polymorphism is not associated with smoking-related COPD in Thailand

OBJECTIVE: Susceptibility to COPD is, in part, genetically determined. Tumour necrosis factor (TNF)-alpha gene promoter polymorphisms have been investigated in different populations with inconsistent results. This study aimed to determine the genetic predisposition in Thai smoking-related COPD patients. METHODOLOGY: The polymorphism at position -308 of the TNF-alpha gene promoter was examined in 57 patients with smoking-related COPD, 67 smoker control subjects, and 116 control anonymous blood donors. Genomic DNA from peripheral blood lymphocytes was used for genotypic analysis by polymerase chain reaction with sequence specific primers. RESULTS: TNF-alpha-308*2 allele frequency was not significantly different between the population control subjects and the smoking-related COPD patients (4.7% vs. 7.9%, P= 0.14). This allele frequency was also not significantly different between smokers with and without COPD (7.9% vs. 7.5%, P= 0.46). CONCLUSIONS: Although it has been speculated that TNF-alpha might have a causal relationship with COPD, a role for the TNF-alpha gene promoter polymorphism in disease development in Thailand was not demonstrated.     

Tumour necrosis factor-alpha (-308) gene polymorphism in obstructive sleep apnoea-hypopnoea syndrome.

Patients with obstructive sleep apnoea-hypopnoea syndrome (OSAHS) have elevated circulating levels of tumour necrosis factor (TNF)-alpha. The hypothesis in this study was that OSAHS might be associated with the TNF-alpha (-308A) gene polymorphism, which results in increased TNF-alpha production. This hypothesis was examined in OSAHS patients, their siblings and population controls. A total of 206 subjects were recruited. All underwent sleep studies and clinical review, and were subsequently classified as having OSAHS or not depending on apnoea-hypopnoea frequency, sex, age and symptoms. All subjects had blood collected and genotyping was performed on DNA extracted from peripheral leukocytes. Some 192 random UK blood donors were used as population controls. The results demonstrated a significant association for TNF-alpha (-308A) allele carriage with OSAHS (OR=1.8; 95% Confidence interval: 1.18-2.75) when compared with population controls. Siblings with OSAHS were significantly more likely to carry the TNF-alpha (-308A) allele. In addition, 21 pairs of male siblings discordant for carriage of the -308A allele showed a significant level of discordance for the OSAHS phenotype. In conclusion, this study demonstrates an association of tumour necrosis factor-alpha (-308A) carriage with obstructive sleep apnoea-hypopnoea syndrome, suggesting that inflammation may be implicated in the pathogenesis of this condition.     

Angiotensin-converting enzyme gene polymorphism and coronary heart disease in Turkish type 2 diabetic patients

OBJECTIVE: It has been suggested that the insertion (I)/deletion (D) polymorphism of the angiotensin-converting enzyme (ACE) may be associated with atherosclerosis.The aim of the study was to examine the association between ACE gene polymorphism and coronary heart disease in Turkish type 2 diabetic patients. METHODS AND RESULTS: A total of 152 (97 female, 55 male) type 2 diabetic patients were included into the study. All patients underwent myocardial perfusion scintigraphic examination and forty-five of them with a perfusion defect underwent coronary angiography.Thirty-eight patients with a coronary stenosis of more than 50% on coronary angiography were considered as having coronary heart disease.The I/D polymorphism was determined by polymerase chain reaction.There was no statistically significant difference in genotypic and allelic frequencies of the ACE I/D polymorphism among patients with and without coronary heart disease (DD:ID:II (%), 32:58:11 and 39:44:17, respectively). CONCLUSIONS: ACE gene polymorphism is not a significant parameter to determine coronary heart disease in Turkish type 2 diabetic patients.     

Methylenetetrahydrofolate reductase polymorphism associated with susceptibility to coronary heart disease in Chinese type 2 diabetic patients

OBJECTIVE: Epidemiological studies have identified hyperhomocyst(e)inemia as an independent risk factor for atherosclerosis. The C677T variant of the methylenetetrahydrofolate reductase (MTHFR) gene, one of the key enzymes catalyzing remethylation of homocysteine, might play a role in the development of coronary heart disease (CHD). In this study, we examined the distribution of the MTHFR genotypes in the Chinese population and the association between the C677T variant and CHD in Chinese type 2 diabetic patients. METHODS: Two hundred and twenty-eight unrelated patients with type 2 diabetes mellitus (126 with coronary heart disease) and 114 healthy control subjects were recruited. The MTHFR genotype was analyzed by PCR followed by HinfI digestion. Plasma total homocysteine levels were measured using high-performance liquid chromatography (HPLC) with fluorescence detection. RESULTS: In 114 healthy control subjects, the frequency of the mutant T allele was 38.0%, comparable to that of a Hong Kong (Chinese) population. The genotype distribution did not differ between control subjects and type 2 diabetic patients (chi(2) = 3.67, P > 0.05). Genotypic analysis revealed that type 2 diabetic patients with CHD displayed a greater prevalence of T allele (45.2%) than type 2 diabetic patients without CHD (30.4%) (chi(2) = 8.72, P < 0.005). The odds ratio for CHD in type 2 diabetic patients in presence of T allele was 1.89 (CI 95%, 1.24-2.88). The MTHFR genotype were different between diabetic patients with and without CHD (chi(2) = 11.98, P < 0.005). Moreover, plasma homocysteine levels were markedly higher in individuals with TT genotype than those with CC or CT genotype or CC plus CT genotype. CONCLUSIONS: The C677T mutation of MTHFR gene is common in the Chinese population. MTHFR C677T gene polymorphism associated with a predisposition to increased plasma homocysteine levels could constitute a useful predictive marker for CHD in Chinese type 2 diabetic patients.     

RAGE基因启动区-429T/C多态与2型糖尿病肾病相关

采用PCR RFLP法对 3 98例 2型糖尿病 (DM )患者和 2 12名正常对照者 (NC) ,进行晚期糖化终末产物受体 (RAGE)基因启动区 -4 2 9T/C多态基因型检测。比较 2型DM合并或未合并肾病组以及NC组间 -4 2 9T/C多态的基因型频率和等位基因频率。结果提示 ,-4 2 9T/C多态与 2型DM肾病的进展有关 ,C等位基因可能是中国人 2型DM临床肾病的保护因素。     

胆固醇酯转运蛋白基因多态性与2型糖尿病合并冠心病的关系

以PCR-RFLP检测胆固醇酯转运蛋白(CETP)基因TagⅠB多态性。CETP基因第1内含子TagⅠ B2B2基因型可能是糖尿病患者冠心病发生的保护性基因型。     

老年冠心病患者血浆中肿瘤坏死因子及其基因多态性的研究

目的　对老年冠心病患者血浆肿瘤坏死因子 (TNF)水平及其基因多态性进行分析 ,探讨其在冠心病发病中的作用。方法　用ELISA及PCR法测定 40例冠心病患者及 30例健康对照者血浆TNF水平及TNF等位基因频率。结果　TNF等位基因频率分布 ,两组之间比较差异无显著性意义 (P >0 .0 5 ) ,而血浆中TNF水平 ,冠心病组明显高于对照组 ,两组之间比较差异有显著性意义 (P <0 .0 0 1) 。结论　TNF基因多态性在冠心病发病机理中可能不起重要作用。TNFA或TNFB基因多态性与冠心病患者血浆TNF水平升高没有关系。     

Tumor necrosis factor-alpha gene promoter polymorphism in patients with familial Mediterranean fever

The proinflammatory cytokine tumor necrosis factor-alpha (TNF-α) plays an important role on the course of disease in familial Mediterranean fever (FMF). TNF-α gene promoter polymorphism may be a marker of susceptibility and severity of FMF. The aim of this study is to evaluate both TNF-α/238 and TNF-α/308 genotypes and allelic distribution in patients with FMF. Forty-one FMF patients and 43 healthy volunteers were included in the study. Genomic DNA was extracted from EDTA-preserved whole blood of whole series of patients and controls. Polymorphism of TNF-α promoter at positions −238 and −308 were detected by using amplification refractory mutation system polymerase chain reaction. TNF-α/238 and TNF-α/308 genotype distributions and allele frequencies of FMF patients and healthy volunteers were found to be similar. Moreover, there was no association between TNF-α/238 and TNF-α/308 genotypes and the frequency of acute attacks in FMF. TNF-α/238 and TNF-α/308 promoter polymorphisms do not seem to be major genetic risk factors for susceptibility to FMF and severity of the disease.     

Association of tumor necrosis factor alpha-308 promoter polymorphism with spondyloarthritides patients in Colombia

The pathogenesis of SpA is considered to be a complex and multi-factorial process and, similar to other autoimmune diseases, includes the activity of proinflammatory cytokines such as TNF alpha. Our study compared the -308 promoter polymorphism of TNF alpha with TNF alpha levels, HLA-B27 status, age at the onset of symptoms, SpA subtype and the clinical degree of activity in Colombian SpA patients and healthy subjects (HS). Comparisons of the TNF alpha-308A genotype among HS and SpA patients (P = 0.004), uSpA patients (P = 0.040), ReA patients (P = 0.001), were significantly different and AS patients (P = 0.110), as were alleles for SpAs (P = 0.007) between patients with SpAs and controls. Initial exploratory analyses demonstrated that the TNF alpha-308 SNP genotype frequencies were different among SpA patients and HS in the Colombian population studied. Furthermore, there was no significant correlation with activity and functional clinical index, serum TNF alpha level or HLA B27 status. Allele frequencies, on the other hand, were correlated with the activity clinical index.     

The tumor necrosis factor alpha -308G>A polymorphism is associated with dementia in the oldest old

OBJECTIVES: To test the hypothesis that the tumor necrosis factor (TNF) -308 G>A promoter gene polymorphism is a risk factor in age-related dementia and longevity. DESIGN: A cross-sectional and a longitudinal study. SETTING: A population-based sample of Danish centenarians. PARTICIPANTS: One hundred-year-old Danes (n=122) from "The Longitudinal Study of Danish Centenarians." Octogenarians (n=174) and healthy volunteers aged 18 to 30 (n=47) served as reference groups. METHODS: Whether the distribution of TNF -308 GG/GA/AA genotypes were different in centenarians than in younger age groups was investigated (Fischer exact test). Furthermore, whether the TNF -308 G>A polymorphism was associated with the prevalence of dementia (logistic regression analysis), the plasma level of TNF-alpha (analysis of variance), and mortality in the following 5 years (Cox regression analysis) within the cohort of centenarians was tested. RESULTS: The distribution of TNF -308 genotypes was not different across the three different age groups, but the GA genotype was associated with decreased prevalence of dementia in centenarians. The few centenarians with AA carrier status had higher mortality risk and tended to show higher plasma levels of TNF-alpha, but the significance was questionable due to a low number of subjects with this genotype. CONCLUSION: It is possible that the TNF -308 A allele is maintained during aging because subjects who are heterozygous for this polymorphism possess the optimal inflammatory response with regard to protection against age-related neurodegeneration.     

Tumour necrosis factor-alpha (TNF-alpha) levels and influence of -308 TNF-alpha promoter polymorphism on the responsiveness to infliximab in patients with rheumatoid arthritis

OBJECTIVE: To investigate the influence of -308 tumour necrosis factor-alpha (TNF-alpha) promoter polymorphism and circulating TNF-alpha levels in the clinical response to the infliximab treatment in patients with rheumatoid arthritis (RA). METHODS: One hundred and thirty-two RA patients were genotyped for TNF-alpha promoter by polymerase-chain reaction restriction fragment-length polymorphism (PCR-RFLP) analysis. Ten patients with the -308 TNF-alpha gene promoter genotype G/A, and 10 with the G/G genotype were selected and received 3 mg/kg of infliximab at Weeks 0, 2, 6, and 14. RESULTS: Both groups showed a significant improvement with treatment in all variables studied. Total mean TNF-alpha levels increased significantly with respect to basal levels in most of patients after treatment [probability (p)=0.04]. Only patients from G/A showed a statistically significant correlation between ACR 50 and the increase of TNF-alpha levels (p<0.03). CONCLUSION: A relationship was detected between ACR criteria of improvement and increased circulating TNF-alpha levels in RA patients subjected to anti-TNF-alpha therapy.     

TNF-alpha -308A promoter polymorphism is associated with enhanced TNF-alpha production and inflammatory activity in Crohn's patients with fistulizing disease

OBJECTIVE: Tumor necrosis factor-alpha (TNF-alpha) plays a key role in the inflammatory response and pathogenesis of Crohn's disease (CD). TNF-alpha -308A polymorphism within the TNF-alpha gene promoter has been associated with enhanced TNF-alpha production in vitro. The aim of this study was to investigate the effect of TNF-alpha promoter polymorphism at -308 on the susceptibility and phenotypic expression of fistulizing CD. METHODS: The distribution of -308 TNF-alpha genotypes was analyzed in 50 patients with fistulizing CD and 100 healthy matched controls. TNF-alpha, interleukin-1beta, and interleukin-6 serum levels were measured by ELISA. Serum amyloid-A, C-reactive protein, alpha1-antitrypsin, alpha1-acid glycoprotein, and haptoglobin were measured by nephelometry. RESULTS: No significant differences were found in the allele frequencies of the polymorphism between patients and controls. However, compared with -308GG patients, those carrying -308AG had a significant increase of serum levels of TNF-alpha (58 +/- 79 vs 8 +/- 19 pg/ml, p < 0.001), interleukin-1beta (36 +/- 45 vs 16 +/- 20 pg/ml, p = 0.048), and acute phase proteins (APPs). -308A carriers had also a higher frequency of arthritis (66% vs 26%, p = 0.039). The logistic regression model showed that the patients carrying -308A polymorphism had a relative risk for developing arthritis of 5.45 (95% CI = 1.1-25.6). No other clinical or analytical findings were predictive for the risk of development of arthritis. CONCLUSIONS: TNF-alpha -308A polymorphism is associated with enhanced TNF-alpha production, more intense inflammatory activity, and an increased risk for arthritis susceptibility in CD patients with fistulizing disease.     

The TNF (-308A) polymorphism is associated with microchimerism in transfused trauma patients

Microchimerism (MC), defined as the persistence of allogeneic cells at low concentrations, is well documented in transfused trauma patients. We hypothesized that genetic polymorphisms linked to cytokine production could contribute to trauma-induced immune modulation and development of microchimerism after transfusion of trauma patients. We used high-throughput SYBR-green-based genotyping of single nucleotide polymorphisms (SNPs) to characterize 59 transfused trauma patients, with MC (n = 30) and without MC (n = 29), for 4 functionally significant SNPs: TNF (–308), IL 10 (–1082), IFNG (+874), and TGFB1 (+915). We then compared likelihood for development of MC and the magnitude of immune suppression among subjects with and without these selected immune response SNPs. We identified a significant association between TNF (–308A) SNP and both development of MC and diminished immune responsiveness. Hence predisposing genetic factors may explain, in part, why only a subset of trauma patients develops transfusion-associated microchimerism.      

Insertion/deletion polymorphism in the angiotensin-l-converting enzyme gene is associated with coronary heart disease in IDDM patients with diabetic nephropathy

Summary Insulin-dependent diabetic (IDDM) patients with diabetic nephropathy have a highly increased morbidity and mortality from coronary heart disease. An insertion (I) /deletion (D) polymorphism in the angiotensin-I-converting enzyme (ACE) gene has been shown to be associated with coronary heart disease. Therefore, we have investigated the role of this ACE/ID polymorphism in 198 IDDM patients with diabetic nephropathy and 190 normoalbuminuric IDDM patients. The prevalence of myocardial infarction and other coronary heart disease was significantly elevated in patients with nephropathy, 19 % (38/198) vs 8 % (15/190), p < 0.001. In the nephropathic group 12 of 63 (19 %), 23 of 95 (24 %), and 3 of 40 (7.5 %) patients with the DD, ID and II genotypes, respectively had a history of coronary heart disease, II vs DD and ID, p < 0.05 when compared to nephropathic patients without coronary heart disease. Multiple logistic regression analysis of the risk factors associated with coronary heart disease in univariate analysis revealed that the II genotype acts as an independent protective factor against coronary heart disease, odds ratio II/DD + ID 0.27 (95 % confidence interval 0.07–0.97, p < 0.05). There was no difference in genotype or allele frequency (D/I) between patients with and without nephropathy, 0.56/0.44 in both groups, but plasma ACE concentration was elevated in patients with nephropathy 609 (151–1504) ng/ml as compared to patients with normoalbuminuria, 428 (55–1630) ng/ml, p < 0.001. We suggest that ACE/ID polymorphism may influence the frequency of life-threatening cardiac complications in IDDM patients suffering from diabetic nephropathy, a condition characterized by increased plasma ACE concentration. [Diabetologia (1995) 38: 798–803] Received: 10 October 1994 and in revised form: 20 December 1994