Obesity is associated with activated and insulin resistant immune cells.
Diabetes Metab Res Rev
; 28(5): 447-54, 2012 Jul.
Article
in En
| MEDLINE
| ID: mdl-22492715
ABSTRACT
BACKGROUND:
Obesity and type 2 diabetes mellitus are characterized by insulin resistance and 'low-grade inflammation'; however, the pathophysiological link is poorly understood. To determine the relative contribution of obesity and insulin resistance to systemic 'inflammation', this study comprehensively characterized circulating immune cells in different grades of obesity.METHODS:
Immune cell phenotypes and activation status were analysed by flow cytometry cross-sectionally in morbidly obese (n = 16, body mass index (BMI) 42.2 ± 5.4 kg/m2), overweight (n = 13, BMI 27.4 ± 1.6 kg/m2) and normal weight (n = 12, BMI 22.5 ± 1.9 kg/m2) subjects.RESULTS:
Obese, but not overweight subjects, had increased activation marker expression on neutrophils, monocytes, T-lymphocytes and polarization of T helper cells towards a pro-inflammatory type 1-phenotype (Th1). Th1 numbers correlated positively with the degree of insulin resistance (homeostasis model assessment, p < 0.05). Lymphocytes from obese subjects showed reduced insulin-stimulated AKT-phosphorylation in vitro. Supra-physiological insulin concentrations did not affect T-cell differentiation, which under normal circumstances would promote an anti-inflammatory T helper type 2-phenotype.CONCLUSIONS:
These results show that morbid obesity is characterized by circulating immune cells that are activated and insulin resistant, with the T-cell balance polarized towards a pro-inflammatory Th1 phenotype. The loss of insulin-induced suppression of inflammatory phenotypes in circulating immune cells could contribute to the systemic and adipose tissue inflammation found in morbid obesity.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Obesity, Morbid
/
Insulin Resistance
/
T-Lymphocytes
/
Biomarkers
/
Diabetes Mellitus, Type 2
/
Insulin-Secreting Cells
/
Inflammation
Type of study:
Risk_factors_studies
Limits:
Female
/
Humans
/
Male
/
Middle aged
Language:
En
Journal:
Diabetes Metab Res Rev
Journal subject:
ENDOCRINOLOGIA
/
METABOLISMO
Year:
2012
Document type:
Article
Affiliation country:
Australia