Indicators of iron status are correlated with adiponectin expression in adipose tissue of patients with morbid obesity

Abstract

AimThe aim of this study was to assess interactions between glucose and iron homoeostasis in the adipose tissue (AT) of obese subjects. MethodsA total of 46 obese patients eligible for bariatric surgery were recruited into the study. Anthropometric and biochemical characteristics were assessed, and biopsies of subcutaneous (SCAT) and visceral adipose tissue (VAT) performed. The mRNA levels of genes involved in iron and glucose homoeostasis were measured in their AT and compared with a pool of control samples. ResultsGene expression of hepcidin (HAMP) was significantly increased in the SCAT and VAT of obese patients, while transferrin receptor (TFRC) expression was reduced, compared with non-obese controls, suggesting a higher iron load in obese patients. Also, mRNA levels of adiponectin (ADIPOQ) were decreased in both SCAT and VAT in obese patients, and correlated negatively with hepcidin expression, while adiponectin expression was positively correlated with TFRC expression in both SCAT and VAT. Interestingly, TFRC expression in VAT correlated negatively with several metabolic parameters, such as fasting blood glucose and LDL cholesterol. ConclusionIron content appears to be increased in the SCAT and VAT of obese patients, and negatively correlated with adiponectin expression, which could be contributing to insulin resistance and the metabolic complications of obesity.