Heroin addiction markedly affects the nutritional and metabolic status and frequently leads to malnutrition. The aim of our study was to compare circulating concentration of adipose tissue-derived hormones leptin, adiponectin and resistin in 12 patients with heroin addiction before and after one-year methadone maintenance treatment with the group of 20 age- and body mass index-matched healthy subjects. Basal serum leptin and adiponectin levels in heroin addicts were significantly decreased (3.4±
0.4 vs. 4.5±0.6 ng/ml and 18.9±3.3 vs. 33.9±3.1 ng/μl, respectively; p<0.05) while serum resistin concentrations were increased compared to healthy subjects (10.1±1.2 vs. 4.6±0.3 ng/ml; p<0.05). Moreover, positive correlation of serum leptin levels with body mass index was lost in the addicts in contrast to control group. One year of methadone maintenance treatment normalized serum leptin, but not serum adiponectin and resistin concentrations. In conclusion, circulating concentrations of leptin, adiponectin and resistin are markedly altered in patients with chronic heroin addiction. These alterations appear to be relatively independent of nutritional status and insulin sensitivity.
The aim of our study was to determine whether adipocyte-derived hormones leptin, adiponectin and resistin contribute to the improvement of insulin sensitivity after very-low calorie diet (VLCD). Therefore, serum levels of these hormones were measured in fourteen obese females before and after three weeks VLCD and in seventeen age- and sex-matched healthy controls. Body mass index, HOMA index, serum insulin and leptin levels in obese women before VLCD were significantly higher than in control group (BMI 48.01±2.02 vs. 21.38±0.42 kg/m2, HOMA 10.72±2.03 vs. 4.69±0.42, insulin 38.63±5.10 vs. 18.76±1.90 μIU/ml, leptin 77.87±8.98 vs. 8.82±1.52 ng/ml). In contrast, serum adiponectin and soluble leptin receptors levels were significantly lower in obese women before VLCD than in the control group. No differences were found in serum glucose and resistin levels between the obese group before VLCD and the control group. VLCD significantly decreased BMI, HOMA index, serum glucose, insulin and leptin levels and increased soluble leptin receptor levels. The changes in serum adiponectin and resistin levels in obese women after VLCD did not reach statistical significance. We conclude that leptin and soluble leptin receptor levels were affected by VLCD while adiponectin and resistin concentrations were not. Therefore, other mechanisms rather than changes in the endocrine function of the adipose tissue are probably involved in the VLCD-induced improvement of insulin sensitivity.