The investigation of adiponectin gene expressions and serum levels in diet induced obese rats subsequent to retroperitoneal adipose tissue denervation

Adiponectin is a adipokine which is synthesized mainly in the white adipose tissue and shows anti-diabetic, anti-atherogenic and anti-inflammatory effects. Besides a number of other factors, the metabolic and secretory properties of adipose tissue is regulated by these sympathetic nervous system. In our study, we aimed to investigate the effects of retroperitoneal fat tissue denervation (both sides) on mRNA expression of adiponectin in the retroperitoneal and epididymal fat tissues and adiponectin concentrations in the serum in rats fed with standard and high fat diet. In our study, there were four experimental groups each containing 8 Sprauge Dawley rats weighing 100-150 g and aging 3-5 weeks: I. Group: Denervated of both retroperitoneal tissue and fed high fat rat diet (YD+), II. Group: Not denervated and fed with high fat rat diet (YD-), III. Group: Denervated of both retroperitoneal tissue and fed standard fat rat diet (SD+), IV. Group: Not denervated and fed with standart rat diet (SD-) (control group). At the end of 10 week period, the animals tissue and serum samples were collected. In serum samples glucose, triglyceride, insulin and adiponectin levels were measured. Furthermore, in retroperitonel and epididymal tissue samples adiponectin mRNA levels were determined by using RT-PCR. Serum adiponectin levels were determined to be higher in high-fat diet and denervated group compared to the control group (p=0.010). In the retroperitoneal adipose tissue in YD+ group gene expression of adiponectin was found to be increased (p=0.023). In the epididymal adipose tissue in YD- group gene expression of adiponectin significantly lower (p=0.021). In conclusion, in the denervated rats depending on diet, it was shown that there were differences in the adiponectin expressions and serum adiponectin levels. It was considered that bilateral denervation and diet could have different effects on the adiponektin levels and synthesis.