Long-term plasma ghrelin and leptin modulation after sleeve gastrectomy in Wistar rats in comparison with gastric tissue ghrelin expression.

BACKGROUND

Sleeve gastrectomy (SG) is a gaining ground operation amongst the ones applied for treatment of morbid obesity. Though SG is a food limiting operation, the removal of the gastric fundus where ghrelin is mainly produced may indicate a hormonal impact of the procedure. The purpose of this experiment is to study how SG affects the levels of ghrelin and leptin.

METHODS

Twenty-four male, adult, diet induced obese Wistar rats were divided randomly into groups, one submitted to SG and the other to a sham operation. Fasting blood samples were taken before the operation and 14 weeks after the operation (leptin and acylated and des-acyl ghrelin levels were measured). Tissue samples from the gastric fundus were taken during the operation and at the end of the experiment, and ghrelin expression was measured with RT-PCR.

RESULTS

Statistically significant weight loss was achieved comparing the weight progress of the SG group and the sham operation group. Serum leptin levels were significantly reduced in the SG group (p < 0.05) but not in the sham operation group. Serum acylated ghrelin was not significantly affected in both groups, but a significant decrease was documented in serum des-acyl ghrelin in the SG group (p < 0.05). RT-PCR analysis of the gastric fundus documented a significant decrease (p < 0.0001) in the expression of ghrelin in the SG group.

CONCLUSIONS

SG may lead in significant long-term weight loss. SG affects the serum levels of leptin and des-acyl ghrelin but not the levels of acylated ghrelin in this animal model.