Alcohol intake modifies leptin, adiponectin and resistin serum levels and their mRNA expressions in adipose tissue of rats.

OBJECTIVE: Alcohol intake is known to interfere with endocrine system functions thus inducing hormonal and metabolic imbalance. The aim was to investigate the impact of chronic intake of mild alcohol concentration on serum leptin, adiponectin and resistin and their gene expression in epididymal adipose tissue (EAT) of rats.
METHODS: The 28 days study was based on 3 experimental groups of adult male Wistar rats: 1/ ad libitum intake of 6 % ethanol solution and pelleted diet (A), 2/ pair fed animals (PF) fed pelleted diet in the same caloric amount as A rats on previous day (alcohol+diet), 3/ control rats (C) with unrestricted intake of water and pelleted diet. RT-PCR method was used for determination of adipokines gene expression in epididymal adipose tissue, serum levels were measured by ELISA kits.
RESULTS: The animals of A group were characterized by reduced food and energy intake (-10 % vs C), lower body mass gain, reduced epididymal fat mass with smaller adipocytes. Alcohol consumption significantly increased glycemia, serum insulin was not affected. The raise of NEFA in A and PF rats gives the evidence of intensified lipolysis due to the deficiency of energy intake. Alcohol consumption significantly increased serum leptin and resistin, elevated adiponectin was present in A and PF rats. In parallel with increased serum levels the expression of adiponectin gene in epididymal adipose tissue was elevated in the same A and PF rats. Leptin and resistin mRNA levels were similar as in C regardless of alcohol intake or pair-fed feeding. Increased leptin and resistin levels positively correlated with glycemia and negatively with the size of adipocytes. Elevated serum leptin and resistin together with high adiponectin after chronic moderate alcohol intake could contribute to alteration of energy metabolism either individually or in reciprocal coordination.
CONCLUSIONS: 28 days consumption of 6 % ethanol solution changed the nutritional status of rats and induced significant elevation of serum leptin and resistin, while elevated gene expression in epididymal adipose tissue was proved for adiponectin only. Elevated serum adipokines could contribute to increased glycemia and altered glucose homeostasis.