We conclude that the TNFA-A allele is associated with decreased insulin resistance as assessed by two independent methods, and may protect against the future development of NIDDM in susceptible individuals.
The aim of this study was to investigate the mRNA expression pattern of the two TNF receptors and their ligand in two adipose tissue depots of glucose-tolerant obese women [n = 18, body mass index (BMI) 48.2 +/- 8.4 kg m-2], obese women with impaired glucose tolerance or overt non-insulin-dependent diabetes mellitus (NIDDM) (n = 10, BMI 49.1 +/- 11.6 kg m-2) and healthy non-obese control subjects (n = 12, BMI 25.8 +/- 2.7 kg m-2).
Tumour necrosis factor (TNF)-alpha, which is considered to play a role in obesity-induced non-insulin-dependent diabetes mellitus and to augment oxidative stress, also suppressed PPAR gamma expression.5.
We conclude that axl expression in myeloid cells in itself does not lead to the onset or progression of leukemia and suggest that ectopic axl expression affects endogenous modulation of TNF-alpha production indirectly resulting in the NIDDM phenotype.
We demonstrate that particular homozygous genotypes of TNF-alpha and GM and KM allotypes epistatically interact with HLA-DQalpha1(Arg 52) and contribute to an increased relative risk of NIDDM.
Recently, increased TNF-alpha production has been observed in adipose tissue derived from obese rodents or human subjects and TNF-alpha has been implicated as a causative factor in obesity-associated insulin resistance and the pathogenesis of type 2 diabetes.
Genetic variation in the tumor necrosis factor (TNF) receptor 2 gene (TNFRSF1B) has shown association with insulin resistance in type 2 diabetes, hypercholesterolemia, coronary artery disease, and essential hypertension.
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.
To analyze the relationship between the peroxisome proliferator-activated receptor-gamma (PPARgamma2) Pro12Ala variant and type-2 diabetes mellitus and its correlation with some cytokine determinants of insulin resistance such as tumor necrosis factor (TNF)-alpha and leptin.
Human obesity and type 2 diabetes are associated with alterations in SREBP1 isoform expression that are reproduced ex vivo by tumor necrosis factor-alpha.
These results suggest that -308 TNF-alpha gene polymorphism may contribute to CHD risk in patients with type 2 diabetes and it could constitute an useful predictive marker for CHD in type 2 diabetic women.
To explore the links between tumor necrosis factor alpha (TNFalpha) and leptin adipose tissue expression and low-grade systemic inflammation and to determine the relationship between inflammation and the degree of adiposity, the presence of type 2 diabetes, and other cardiovascular risk factors.
We conclude that the -308A allele of the promoter polymorphism (G-308A) of the TNF-alpha gene is a predictor for the conversion from IGT to type 2 diabetes.
Therefore, we examined the relationship between the incidence of type 2 diabetes in Taiwanese and two polymorphisms of the TNF-alpha promoter region (positions -238 and -308) as well as the correlation between these polymorphisms and the patients' biochemical manifestations.
To study whether the TNF alpha gene could be such a modifying gene, we studied TNF alpha promoter polymorphisms (G-->A substitution at positions -308 and -238) in relation to HLA-DQB1 genotypes in type 2 patients from mixed type 1/2 families or common type 2 diabetes families as well as in patients with adult-onset type 1 diabetes and control subjects.
Analysis of the -308 TNFalpha polymorphism in patients with type 2 diabetes and in control subjects revealed that the heterozygous TNF1/TNF2 genotype was significantly less frequent in the patient group (p=0.003), suggesting that TNF1/TNF2 may be considered as a protective marker against type 2 diabetes (OR=0.58).
The tumor necrosis factor system plays an important role in the pathogenesis of obesity and type 2 diabetes (DM), by a complex and only partially understood mechanism.