Evidence from clinical observational studies and animal experiments suggests that hypogonadism is associated with the metabolic syndrome. In most of the experiments, androgen deficiency is induced by gonadectomy in the adulthood and relatively short-term effects of hypogonadism on metabolic parameters are usually observed. The purpose of this study was to evaluate the metabolic effects of long-term androgen deficiency starting before puberty in middle-aged male rats. The components of the metabolic syndrome were examined in male, female and gonadectomized male rats at the age of 18months. Sex differences were observed in plasma testosterone, cholesterol, high-density lipoproteins and also in body weight and in glycemia dynamics during oral glucose tolerance test. Gonadectomy and long-term hypogonadism did not affect most of the analyzed metabolic parameters such as blood pressure, glycemia, plasma insulin and uric acid. The only exception was the significantly higher liver enzymes in plasma and triacylglycerol in liver found in gonadectomized males. Except low-density lipoprotein, neither treatment of middle-aged males and females with letrozole, nor supplementation of estradiol as the metabolite of testosterone in gonadectomized male rats changed any of the observed metabolic parameters. Our results suggest that long-term hypogonadism started before puberty does not induce metabolic syndrome in middle-aged male rats, but may affect the liver. Sex differences in metabolic parameters in middle-aged rats are not mediated by testosterone. Whether hypogonadism predispose to metabolic syndrome in combination with other risk factors needs further clarification.
Experimental gerontology. 2017 Aug 11 [Epub ahead of print]
Veronika Borbélyová, Emese Domonkos, Janka Bábíčková, Ľubomíra Tóthová, Mária Kačmárová, Oľga Uličná, Daniela Ostatníková, Július Hodosy, Peter Celec
Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, Sasinkova 4, 811 08 Bratislava, Slovakia., Department of Animal Physiology and Ethology, Faculty of Natural Sciences, Comenius University, Mlynská dolina, Ilkovičova ulica č. 6, 842 15, Bratislava, Slovakia., Pharmacobiochemical Laboratory of Third Department of Internal Medicine, Faculty of Medicine, Comenius University, Sasinkova 4, 811 08 Bratislava, Slovakia. Electronic address: ., Institute of Physiology, Faculty of Medicine, Comenius University, Sasinkova 2, 813 72 Bratislava, Slovakia. Electronic address: ., Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, Sasinkova 4, 811 08 Bratislava, Slovakia; Institute of Physiology, Faculty of Medicine, Comenius University, Sasinkova 2, 813 72 Bratislava, Slovakia., Institute of Molecular Biomedicine, Faculty of Medicine, Comenius University, Sasinkova 4, 811 08 Bratislava, Slovakia; Institute of Pathophysiology, Faculty of Medicine, Comenius University, Sasinkova 4, 811 08 Bratislava, Slovakia; Department of Molecular Biology, Faculty of Natural Sciences, Comenius University, Mlynská dolina, Ilkovičova ulica č. 6, 842 15 Bratislava, Slovakia. Electronic address: .