Evaluation of non-alcoholic fatty liver disease development and epicardial adipose tissue in rats with induced hypothyroidism

Purpose: It had been shown that Hypothyroidism can be associated with metabolic syndrome, obesity and hyperlipidemia. Therefore, it is estimated that NAFLD (Nonalcoholic fatty liver disease) may play a role in the pathogenesis of atherosclerosis and thyroid hormones. EAD (epicardial adipose tissue) is a kind of visceral fat. EAD thickness increase is known to play an important role in the pathogenesis and development of CAD (Coronery Artery Disease). However, during the literature screening there some opposite results that evaluate the association between NAFLD with hypothyroidism, and atherosclerosis with EAD thickness increase is available In our study, hypothyroidism developed model in rats, NAFLD histopathology, aimed to evaluate the thickness of atherosclerosis and EAD. Method: 16 adult male Wistar albino rats were used. Hypothyroidism created group was created by giving methimazole (n = 8), 0.025% in drinking water for 12 weeks (MMI; Sigma, USA).After 12 weeks Obesity evaluation was performed with Lee index. After eight hour fasting, cervical dislocation was performed by taking venous blood from the systemic circulation under anesthesia. Plasma glucose, ALT, AST, LDL, HDL, triglycerides, TSH, FT4, FT3 and visfatin levels were studied. In order to histopathological examination of the heart and liver,the fractions were stained with hematoxylin-eosin and then "Oil Red-O" and were examined by light microscope.The data obtained from this study were analyzed using SPSS 17.0.When p value of <0.05 was considered statistically significant. Symptoms: At the end of the study, mild hepatosteatozis mild was found in the all hypothyroidism created group. As histopathologically atherosclerosis finding and EAD(epicardial adipose tissue) increase were not detected. The group that was formed hypothyroidism, compared with the control group, a statistically significant level, low FT4 and FT3, TSH, ALT, AST, fasting glucose, LDL were detected high. Visfatin levels were similar in the two groups. Result: As a result, on the rats that were created hypothyroid model, we found that mild hepatosteatozis was seen histologically, different from the control group.Our study causes us to think hypothyroidism causes to NAFLD. We did not observe an association between Hypothyroidis, histopathological findings of atherosclerosis and EAD. Key Words: Hypothyroidi, hepatosteatosis, epicardial adipose tissue, visfatin, atherosclerosis