The effect of obesity, impaired carbohydrate metabolism and bariatric surgery on adiponectin and leptin mRNA levels in different adipose tissue depots

Abstract

Objective. To determine the effect of morbid obesity, impaired carbohydrate metabolism and bariatric surgery on adiponectin and leptin mRNA levels in subcutaneous and visceral adipose tissue.Design and methods. The study included 30 obese female patients. Eleven patients had co-existent impaired carbohydrate metabolism. The control group consisted of 10 healthy non-obese women. In all obese patients, subcutaneous and visceral adipose tissue samples were taken during bariatric surgery. In obese patients 1 year after the intervention and in control individuals subcutaneous adipose tissue samples were collected. The circulating levels of adiponectin and leptin were determined by the enzyme immunoassay. The amount of adiponectin and leptin mRNA in adipose tissue were analyzed by real-time polymerase chain reaction.Results.During the first postoperative year, all patients showed a monotonous decrease in body mass index. After the surgery, the circulating levels of adiponectin and leptin returned to reference values (for healthy population). Compared with the control group, obese patients showed 1,4-times lower adiponectin mRNA level (p < 0,01) in subcutaneous adipose tissue, while leptin mRNA level did not change. In obese patients with impaired carbohydrate metabolism, the adiponectin mRNA level was twice lower in visceral adipose tissue (p < 0,01), compared to patients without impaired carbohydrate metabolism. In obese patients with and without impaired carbohydrate metabolism, mRNA levels of adipokines were more than 2-times lower in visceral adipose tissue compared to subcutaneous adipose tissue (p < 0,05). In subcutaneous adipose tissue, 1 year after bariatric intervention, adiponectin mRNA level decreases by 4,5 times (p < 0,01) in obese patients, and leptin mRNA level decreases by 3,1 times (p < 0,01) in patients with obesity and by 1,5 times (p < 0,05) in patients with obesity and impaired carbohydrate metabolism. Neither adiponectin nor leptin mRNA levels from adipose tissue of different localization showed statistically significant correlation. No correlation was found between the levels of circulating adipokines and their mRNA amount in adipose tissue.Conclusions.Our results indicate that adiponectin and leptin mRNA levels in adipose tissue cells depend on their localization in the body, as well as the presence of obesity and impaired carbohydrate metabolism. We also showed that adiponectin and leptin mRNA levels in adipose tissue change in response to bariatric surgery.