Tumor necrosis factor alpha and interferon alpha in patients with myocarditis.

AIM:To elucidate the role of tumor necrosis factor alpha (TNF alpha) and interferon alpha (INF alpha) in pathogenesis of infectious-immune myocarditis (M) and myocarditic cardiosclerosis (MCS). MATERIAL AND METHODS: Patients with infectious-immune myocarditis (n=27) and myocarditic cardiosclerosis with symptoms of heart failure (n=19). Blood levels of TNF alpha and INF alpha were measured by immune enzyme analysis. RESULTS: Mean levels of INF alpha and TNF alpha in patients with M (75+/-47 and 304+/-102 rg/ml respectively) were significantly higher than in patients with MCS and healthy donors (31+/-14 and 83+/-39; 38+/-18 95+/-58 rg/ml, respectively, p<0.05). Levels of INF alpha and TNF alpha significantly differed between patients with benign and malignant course of M (99+/-46 and 354+/-100; 39+/-10 227+/-42 rg/ml, p<0.05). Phytohemagglutinine induced TNF alpha production by leucocytes in patients with malignant M (1432+/-515 rg/ml) was higher (p<0.05) while in patients with benign M (131+/-54 rg/ml) lower (p<0.01) than in healthy donors (255+/-98 rg/ml). Patients with malignant compared with those with benign course of myocarditis had lower ejection fraction (25.9+/-12.1 and 42.5+/-11,2%, respectively, p<0.003) and higher inhospital mortality (16.6 and 0%, respectively). CONCLUSION: It is most probable that factors of regulation of INF alpha and TNF alpha production occupy an import place among mechanisms of malignant transformation of myocarditis.     

Tumor necrosis factor alpha in patients with acute myocardial infarction

Acute myocardial infarction (AMI) is a myocardial necrosis occurring due to persistent coronary ischemia, in which inflammation plays an important role and heart failure is a common complication. The present work was undertaken to clarify the role of Tumor Necrosis Factor Alpha (TNF-alpha) in acute myocardial infarction (AMI). The study was conducted on 20 newly diagnosed AMI patients and 10 healthy age and sex matched controls. Sequential estimation of plasma TNF alpha level was carried out at admission, 24 and 48 hours post admission using ELISA. AMI patients showed a significant increase of plasma TNF-alpha level on admission, and 24 hours post admission but not after 48 hours. However, a significant increase was still seen at 48 hours post admission in patients with signs of heart failure but not in those without signs of heart failure. A significant positive correlation was found between plasma TNF-alpha level and CPK level at admission. On the other hand a significant negative correlation was found between these 2 parameters at 24 and 48 hours post admission. It is concluded that TNF-alpha may be an early marker of myocardial damage because of the early increase of its level after ischemic injury instead of being late consequence of extensive tissue necrosis. TNF-alpha level may be an important indicator of the severity of AMI and the occurrence of heart failure.     

Tumor necrosis factor alpha -238G>A genotype alters postprandial plasma levels of free fatty acids in obese individuals with type 2 diabetes mellitus

Tumor necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine that impairs insulin action and alters lipid metabolism. We investigated the effects of genetic polymorphisms of TNF-alpha on circulating biomarkers of insulin resistance and lipid metabolism during an 8-hour metabolic profile test and a 2-hour oral glucose tolerance test in subjects with type 2 diabetes mellitus. Subjects (N = 123) recruited were type 2 diabetic men (n = 56) and women (n = 67) aged 36 to 75 years with a body mass index of at least 25 kg/m(2). Blood samples were collected to determine postprandial changes in circulating lipid levels and biomarkers of insulin resistance. Subjects were genotyped by polymerase chain reaction-restriction fragment length polymorphism for the TNF-alpha -238G>A, -308G>A, and -863C>A polymorphisms. Compared with subjects who were homozygous for the -238G allele, carriers of the -238A allele had an altered ability to suppress postprandial free fatty acids as shown by an increased net incremental area under the curve (0.26 +/- 2.44 vs -1.33 +/- 2.71 mEq h(-1) L(-1), P = .002) during the 8-hour metabolic profile test. This effect was observed in obese (1.04 +/- 2.42 vs -1.68 +/- 2.70 mEq h(-1) L(-1), P = .0004) but not in non-obese (-0.63 +/- 2.20 vs -0.95 +/- 2.71 mEq h(-1) L(-1), P = .6) individuals. Among obese subjects, carriers of the -308A allele had greater insulin resistance as estimated by the homeostasis model assessment of insulin resistance index (4.36 +/- 2.83 vs 2.85 +/- 1.75, P = .01), but no differences were observed among non-obese subjects (2.19 +/- 1.24 vs 1.97 +/- 0.90, P = .6). Our findings suggest that the -238G>A and -308G>A polymorphisms of TNF-alpha alter circulating free fatty acids and insulin resistance in obese subjects with type 2 diabetes mellitus.     

Tumor necrosis factor alpha promoter polymorphisms in patients with juvenile idiopathic arthritis

OBJECTIVE: To investigate the potential association of tumor necrosis factor-alpha (TNF) promoter alleles within subtypes of juvenile idiopathic arthritis (JIA) compared to healthy controls in a Caucasian population. METHODS: TNF-alpha promoter polymorphisms at positions -163, -238, -244, -308, -376 were determined in 228 patients with JIA and 196 healthy individuals. Genomic DNA was isolated and a PCR fragment of about 500 base pairs of the TNF gene promoter were amplified by PCR. Detection of polymorphisms was achieved by a single sequencing procedure. RESULTS: The TNF -238A allele was more frequent in the psoriatic arthritis JIA subgroup compared to healthy controls as well as to non-psoriatic JIA patients (p < 0.001, chi-square-test) and was associated with the more frequent occurrence of joint erosion (p < 0.05, chi-square-test). The frequency of the TNF -308A allele was significantly lower in patients with rheumatoid factor negative polyarthritis JIA patients compared to healthy controls, respectively (p < 0.05, chi-square-test). Joint erosions were detectable more often in rheumatoid factor negative polyarthritis JIA patients with the G/A genotype (80%) than in those with the G/G genotype (45%) (p = 0.20). The rare alleles at position -376 or at positions -163 and -244 were found very infrequently. CONCLUSION: TNF promoter polymorphisms may play a role in the pathogenesis of JIA. The TNF-238A allele seems to be associated with juvenile psoriatic arthritis. The TNF-308A allele is less frequently found in rheumatoid factor negative but not in rheumatoid factor positive polyarthritis and may therefore be associated with a more severe disease, while the more common TNF-308G allele may be protective.     

Tumor necrosis factor alpha promoter polymorphisms and insulin resistance in nonalcoholic fatty liver disease

BACKGROUND & AIMS: Nonalcoholic fatty liver disease, which can range from fatty liver alone to nonalcoholic steatohepatitis and cirrhosis, is related to insulin resistance. Tumor necrosis factor alpha (TNF-alpha) may induce insulin resistance, and polymorphisms of its promoter have been associated with an increased release of this cytokine. We analyzed (1) the prevalence of insulin resistance, (2) the prevalence of the 238 and 308 TNF-alpha polymorphisms, and (3) the relationship among TNF-alpha polymorphisms, insulin resistance, and the occurrence of steatohepatitis in 99 patients with nonalcoholic fatty liver diagnosed by ultrasonography and confirmed by histologic analysis in the 53 who underwent biopsy. METHODS: Insulin resistance was evaluated by the homeostatic metabolic assessment insulin resistance indices and TNF-alpha polymorphisms by polymerase chain reaction and restriction fragment length polymorphism analysis. RESULTS: Insulin resistance was detected in almost all of the patients and was more severe in those with steatohepatitis. The prevalence of the 238, but not of the 308, TNF-alpha polymorphism was higher in subjects with nonalcoholic fatty liver than in controls (31% vs. 15%; P < 0.0001), and patients positive for TNF-alpha polymorphisms had higher insulin resistance indices, a higher prevalence of impaired glucose tolerance, and a lower number of associated risk factors for steatosis. CONCLUSIONS: TNF-alpha polymorphisms could represent a susceptibility genotype for insulin resistance, nonalcoholic fatty liver, and steatohepatitis.     

Short-term suppression of plasma free fatty acids fails to improve insulin sensitivity when intramyocellular lipid is elevated.

AIMS: Metabolic responses to manipulation of the plasma free fatty acid (FFA) concentration were assessed in six healthy men via cross-over design to determine whether FFAs independently influence insulin sensitivity. METHODS: Intramyocellular lipid (IMCL) was measured by proton magnetic resonance spectroscopy and insulin sensitivity via frequently sampled intravenous glucose tolerance test (IVGTT) after 67 h of two identical low carbohydrate/high fat (LC) diets which were used to elevate IMCL and plasma FFAs. To uncouple the influence of FFAs and IMCL on insulin sensitivity, FFAs were suppressed 30 min prior to and during IVGTT in one treatment [LC + nicotinic acid (NA)] by NA ingestion. RESULTS: Vastus lateralis IMCL was significantly elevated in LC (13.3 +/- 1.1 x 10(-3)) and LC + NA (13.5 +/- 1.1 x 10(-3)) (P < 0.01 for both), but was not different between conditions (P > 0.05). Plasma FFAs were raised in LC (0.79 +/- 0.08 mmol/l) and LC + NA (0.80 +/- 0.11 mmol/l) (P < 0.01 for both) and were significantly reduced by NA ingestion prior to (0.36 +/- 0.05 mmol/l, P < 0.01) and during IVGTT (P < 0.05) in LC + NA. Despite marked differences in plasma FFA availability, insulin sensitivity and glucose tolerance were not different between LC and LC + NA (P > 0.05 for both). CONCLUSIONS: Plasma FFAs appear to exert no immediate effect on insulin sensitivity/glucose tolerance independent of their action on intracellular lipid moieties. Further research is required to elucidate the duration of FFA suppression required to restore insulin sensitivity following lipid-induced insulin resistance.     

Tumor necrosis factor alpha and insulin resistance in obese type 2 diabetic patients

The relationship between basal serum tumor necrosis factor alpha (TNFalpha) levels and peripheral tissue (muscle) sensitivity to insulin was examined in 63 subjects with normal glucose tolerance (NGT), 18 subjects with impaired glucose tolerance (IGT), and 123 patients with type 2 diabetes mellitus (T2DM). The BMI was similar in NGT (28.8+/-0.7 kg/m(2)), IGT (31.1+/-1.0), and T2DM (30.0+/-0.4) groups. The fasting serum TNFalpha concentration in T2DM (4.4+/-0.2 pg/ml) was significantly higher than in NGT (3.1+/-0.2) and IGT (3.4+/-0.2; both P<0.05). In T2DM the fasting plasma glucose (FPG=183+/-5 mg/dl) and insulin (FPI=17+/-1 micro U/ml) concentrations were significantly higher than in NGT (FPG=95+/-1; FPI=10+/-1) and IGT (FPG=100+/-2; FPI=13+/-1; all P<0.01). The rate of total body insulin-mediated glucose disposal (Rd; 40 mU/m(2) min euglycemic insulin clamp in combination with (3)H-glucose) was reduced in T2DM (102+/-3 mg/m(2) min) compared with NGT (177+/-10) and IGT (151+/-14; both P<0.01). The serum TNFalpha concentration was inversely correlated with Rd (r=-0.47, P<0.0001) and positively correlated with both FPG (r=0.32, P=0.004) and FPI (r=0.32, P=0.004) in NGT plus IGT. No correlation was observed between serum TNFalpha and Rd (r=-0.02), FPG (r=0.15), or FPI (r=0.15) in T2DM. In stepwise multiple regression analysis using age, sex, BMI, FPG, FPI and serum TNFalpha concentration as independent variables, only BMI and serum TNFalpha concentration were significant and independent predictors of Rd (r(2)=0.29, P<0.0001) in the NGT plus IGT group, while FPG and FPI were significant and independent predictors of Rd (r(2)=0.13, P<0.0001) in T2DM. These results suggest that: (i) an increase in circulating TNFalpha concentration is associated with peripheral insulin resistance and increased plasma glucose and insulin levels prior to the onset of type 2 diabetes; and (ii) the further deterioration in peripheral insulin resistance in T2DM (compared with NGT and IGT) is unrelated to the increase in serum TNFalpha concentration.     

Two-year delay in ulcerative colitis diagnosis is associated with anti-tumor necrosis factor alpha use

BACKGROUND Ulcerative colitis(UC)is an uncommon inflammatory bowel disease(IBD).However,its incidence has recently increased in South Korea.Moreover,UC diagnoses are frequently delayed,and the relationship between diagnostic delay and UC prognosis has not been extensively studied in South Korean patients.AIM To identify meaningful diagnostic delay affecting UC prognosis and to evaluate risk factors associated with diagnostic delay in South Korean patients.METHODS Medical records of 718 patients with UC who visited the outpatient clinic of six university hospitals in South Korea were reviewed;167 cases were excluded because the first symptom date was unknown.We evaluated the relationship between the prognosis and a diagnostic delay of 3,6,12,18,and 24 mo by comparing the prognostic factors[anti-tumor necrosis factor(TNF)-αuse,admission history due to acute flare-ups,frequent admission due to flare-ups,surgery associated with UC,and the clinical remission state at the latest followup]at each diagnostic interval.RESULTS The mean diagnostic interval was 223.3±483.2 d(median,69 d;75th percentile,195 d).Among the prognostic factors,anti-TNFαuse was significantly increased after a diagnostic delay of 24 mo.Clinical risk factors predictive of a 24-mo diagnostic delay were age<60 years at diagnosis[odd ratio(OR)=14.778,95%confidence interval(CI):1.731-126.121],smoking history(OR=2.688,95%CI:1.239-5.747,P=0.012),and misdiagnosis of hemorrhoids(OR=11.066,95%CI:3.596-34.053).Anti-TNFαuse was associated with extensive UC at diagnosis(OR=3.768,95%CI:1.860-7.632)and 24-mo diagnostic delay(OR=2.599,95%CI:1.006-4.916).CONCLUSION A diagnostic delay>24 mo was associated with increased anti-TNFαuse.Age<60 years at diagnosis,smoking history,and misdiagnosis of hemorrhoids were risk factors for delayed diagnosis.     

A tumour necrosis factor alpha polymorphism is not associated with rheumatoid arthritis.

OBJECTIVE--To determine whether a polymorphism within the tumour necrosis factor alpha (TNF alpha) gene is associated with susceptibility to, or severity of, rheumatoid arthritis (RA). METHODS--Consecutive patients with recent onset RA were enrolled in a prospective trial. DNA was collected, disease activity was measured at presentation, and radiographic progression at three years was assessed. Typing of TNF alpha was by polymerase chain reaction and single stranded conformation polymorphism analysis. RESULTS--No association of TNF alpha alleles and susceptibility to, or severity of, RA was demonstrated. CONCLUSIONS--These results indicate that this TNF alpha polymorphism does not play a part in the genetic background of RA.     

Increased abdominal visceral fat is associated with reduced bone density in HIV-infected men with lipodystrophy

OBJECTIVE: To examine the relationship between bone density and changes in regional and whole body composition in HIV-infected men with and without lipodystrophy. DESIGN: Cross-sectional, observational study of HIV-infected men with and without lipodystrophy and matched HIV-negative controls. SETTING: Tertiary care academic medical institution. PATIENTS: A total of 59 men, belonging to three different groups: HIV-positive men with lipodystrophy (n = 21), HIV-positive men without lipodystrophy (n = 20), and age-matched and body mass index-matched HIV-negative controls (n = 18). METHODS: Bone density, markers of bone turnover and indices of calcium metabolism were measured in all subjects. Quantitative computed tomography was used both to determine volumetric bone density of the spine and to quantify abdominal visceral fat. Dual energy X-ray absorptiometry was used to determine whole body composition and bone density. Statistical comparisons were performed according to lipodystrophy categorization and protease inhibitor exposure. RESULTS: Men with HIV-associated lipodystrophy had reduced lumbar spine bone density compared with both HIV-infected non-lipodystrophic men [mean +/- SD, 132 +/- 29 versus 154 +/- 30 mg/cm(3); P = 0.02] and HIV-negative controls [mean +/- SD 132 +/- 29 versus 148 +/- 18) mg/cm(3); P = 0.04]. Lumbar spine bone density was reduced significantly in HIV lipodystrophy patients independently of protease inhibitor use. In an analysis among all HIV-infected subjects, increased visceral abdominal fat area was associated with decreased lumbar spine bone density (r, -0.47; P = 0.002). The association between visceral fat and bone density remained significant (P = 0.007) after controlling for age, body mass index, lowest body weight, protease inhibitor use, and extremity fat in a multivariate regression model. Markers of bone turnover were not related to bone density or lipodystrophy status. CONCLUSIONS: Lumbar spine bone density is reduced in association with increased visceral fat in HIV-infected men with lipodystrophy. Further studies are needed to determine the mechanisms of osteopenia in HIV lipodystrophy and whether increased marrow fat occurs in such patients and affects bone density.     

Tumor necrosis factor soluble receptor p55 and lipid peroxidation in patients with acute alcoholic hepatitis

OBJECTIVES: In experimental models, liver injury induced by ethanol, cytotoxic activity of tumor necrosis factor (TNF) -alpha is principally mediated by TNF receptor p55 (TNFRp55). Among the various mechanisms underlying the toxic effects of TNF-alpha, overproduction of reactive oxygen species seems to play a key role in mediating TNF-alpha-induced cytotoxicity. The aim of this study was to evaluate, in patients with alcoholic liver disease, whether alcohol TNFRp55-mediated hepatotoxicity could account for lipid peroxidation expressed by significant increase in serum thiobarbituric reactive acid substances (TBARS) content, and could be amplified by decrease in blood total glutathione content and decrease in plasma antioxidant protective capacity. METHODS: We studied 27 patients with histological alcoholic liver disease (five fibrosis, six acute alcoholic hepatitis (AAH) without cirrhosis, four cirrhosis without AAH, and 12 cirrhosis with AAH. TNFsRp55 and TNFsRp75 plasma levels were measured using ELISA assays. Plasma lipid peroxidation was evaluated by the content of TBARS. Total glutathione (tGSH) content in blood was determined by a kinetic assay. The sensitivity of erythrocytes to an oxidative stress and the plasma antioxidant protective capacity were simultaneously determined by a simple method. RESULTS: In the 18 patients with mild or severe AAH, the plasma levels of TNFsRp55 were negatively correlated with tGSH and were positively correlated with TBARS, with total bilirubin and with discriminant function. tGSH was positively correlated with plasma selenium. The plasma levels of TNFsRp75 were positively correlated with TBARS and with total bilirubin. There was no significant correlation with the mean inhibitory 50% plasma volume or with the percentage of hemolyzed erythrocytes. CONCLUSIONS: Our data support the notions that, in patients with AAH, TNFsRp55 probably mediates cytotoxicity of TNF-alpha, and that cytotoxic effect could be amplified by tGSH depletion in enhancing lipid peroxidation.     

Positive Chlamydia pneumoniae serology is associated with elevated levels of tumor necrosis factor alpha in patients with coronary heart disease

Infectious agents are possible stimulators of inflammation in atherogenesis. The aim of this study was to investigate if Chlamydia pneumoniae and Helicobacter pylori were associated with elevated levels of tumor necrosis factor alpha (TNFalpha) and interleukin-6 in coronary heart disease (CHD) patients (n=193) and age- and sex-matched controls (n=193) as markers of increased inflammatory activity. C reactive protein (CRP) and fibrinogen were also included. Serologic status towards the two bacteria was measured and levels of the inflammatory markers were compared between seropositives and seronegatives, each study group being evaluated separately. In CHD patients Chlamydia lipopolysaccharide (LPS) IgA seropositivity predicted elevated TNFalpha levels (P=0.009), still statistically significant after adjustment for traditional cardiovascular risk factors (P=0.005). Chlamydia LPS IgG seropositivity independently predicted fibrinogen levels in CHD patients (P=0.028), while no association between serology and inflammatory markers were observed among controls. H. pylori seropositivity alone was not associated with any increase in the inflammatory markers in any of the two groups. However, in CHD patients seropositivity to both agents predicted higher levels of TNFalpha (P=0.041), CRP (P=0.037) and fibrinogen (P=0.001) compared to double seronegativity. We conclude that C. pneumoniae LPS seropositivity may contribute to increased vascular inflammation in CHD patients, possibly even more pronounced when present in combination with H. pylori seropositivity.     

Individual free fatty acids in patients with liver disease

The total free fatty acids, blood glucose, and individual free fatty acids were studied in 8 patients with viral hepatitis and 13 with cirrhosis. The results were compared with those obtained in 9 normal control subjects. Free fatty acids were significantly elevated in liver patients as compared with normal controls. A fall in free fatty acids following ingestion of amino acids and dextrose was noted in normal subjects as well as liver patients. Glucose tolerance test, when done on patients with liver disease, was abnormal in most cases. Highly significant differences were found in the composition of individual free fatty acids in liver patients as compared with normal subjects. Arachidonic and linoleic acids were decreased, while monounsaturated and saturated fatty acids were increased in patients with viral hepatitis and cirrhosis. No significant changes were noted in the percent composition of individual free fatty acids following ingestion of amino acids and dextrose.Decreased.     

肿瘤坏死因子α致暴发性肝功能衰竭小鼠肠上皮细胞凋亡的作用

目的研究肿瘤坏死因子α(TNFα)对暴发性肝功能衰竭(FHF)小鼠肠黏膜上皮细胞凋亡的作用。方法用D-氨基半乳糖(GalN) 脂多糖(LPS)或TNFα造FHF小鼠模型;酶联免疫吸附法测定血清TNFα含量;光学显微镜和电子显微镜观察肠组织;末端转移酶介导的dUTP缺口末端标记法检测肠组织细胞凋亡情况;免疫组织化学法检测肿瘤坏死因子受体I(TNFRⅠ)蛋白在肠组织的表达与分布。结果实验各组动物各时间点光学显微镜下肠黏膜上皮细胞结构均保持完整,电镜下可见肝功能衰竭组有典型的凋亡细胞;对照组、LPS组、GalN组血清TNFα水平几乎正常,凋亡率低且基本没有TNFRⅠ蛋白表达;GalN LPS组血清TNFα水平12h明显升高(P<0.01),且TNFRⅠ蛋白在6h(大肠:2.82e 4±4.60e 3;小肠:1.14e 4±2.13e 3)即有表达,此时肠上皮细胞凋亡不明显,9h和12hTNFRⅠ蛋白表达明显增加,同时肠上皮细胞凋亡也明显。用GalN TNFα造FHF模型,结果也与GalN LPS组类似。应用抗TNFα抗体,可降低TNFRⅠ蛋白表达和减少肠上皮细胞凋亡的发生。结论TNFα能诱导肝功能衰竭小鼠肠上皮细胞凋亡,抗TNFα抗体能阻断这一作用;在FHF的模型动物中,TNFRⅠ蛋白表达增多,TNFRⅠ蛋白表达与肠上皮细胞凋亡在一定程度上呈正相关。