Investigation of serum and gonadal ghrelin, obestatin, nesfatin-1 expression in rats with fructose-induced metabolic syndrome

ABSTRACTINVESTIGATION OF SERUM AND GONADAL GHRELIN, OBESTATIN, NESFATIN-1 EXPRESSION IN RATS WITH FRUCTOSE-INDUCED METABOLIC SYNDROMEMetabolic syndrome (MetS) is a complicated disease. The exact mechanism is not known, but has been associated with obesity, insulin resistance, proinflammatory status and hormonal level. The objective of this study is to show how ghrelin, obestatin (OBS) and nesfatin-1 (NES) expressions change in the reproductive system tissues of rats. Whether their expressions are correlated with serum values and whether they are connected to other hormones associated with infertility. The study included four groups of Sprague Dawley rats, male and female ? controls and male and female ? MetS groups. The rats in the MetS group were fed ad libitum (with standard rat pellets and a 10% fructose solution in their drinking water) for 12 weeks. The control rats were fed ad libitum with standard rat pellets over the same week period. Biochemical parameters were measured using Konelab-60 equipment and infertility hormones in Immunlight-2000. Serum and tissue ghrelin, OBS and NES values were determined by the ELISA method and the immunoreactivity of the peptide hormones of reproductive system tissues were quantified by the ABC method. Açlık serum insulin, glucose, ALT, GGT, triglyceride, LDL-C, and total cholesterol (TC) levels were found statistically significantly higher and the HDL-C amount was found significantly lower in the MetS groups. Changes in the infertility hormone values were not statistically significant. NES amounts in the serum of the rats with MetS were observed to increase significantly in comparison to those in the control group. Serum OBS and ghrelin levels were lower, but the decrease did not have a statistical significance.Amounts of ghrelin in the reproductive organ tissues of the animals with MetS were found to have decreased, while NES expression in the same tissues increased. Obestatin was also found to have decreased, but not in the seminal glands. Expression of the hormones in the reproductive tissues and the intensity of immunoreactivity were parallel to tissue hormone quantities. According to these results, it is seen that as changes brought about by MetS have a negative impact on reproductive systems, it is important to restore the altered hormones to the normal physiological limits and these results will provide insights into reproductive biochemistry.Key words: Metabolic syndrome, ghrelin, obestatin, nesfatin-1, infertility