Serum agouti-related protein (AgRP) levels in bipolar disorder: Could AgRP be a state marker for mania?
PSYCHIATRY RESEARCH
Authors: Parlak, Naci; Gorgulu, Yasemin; Cinar, Rugul Kose; Sonmez, Mehmet Bulent; Parlak, Ebru
Abstract
Orexigenic and anorexigenic peptides, especially agouti-related protein (AgRP) and leptin, play important roles in the regulation of energy homeostasis in bipolar disorder. AgRP regulates energy metabolism by increasing appetite and decreasing energy expenditure. The resting energy expenditures of patients with manic bipolar disorder are higher than those of controls. Due to the effects of AgRP on energy expenditure and the increased physical activity of manic patients, we hypothesised that serum AgRP levels may be lower in manic patients than in euthymic patients and controls. There was a total of 112 participants, including 47 patients in the manic group, 35 patients in the euthymic group and 30 healthy controls. For this study, serum AgRP, leptin, cholesterol, and cortisol levels were measured and compared between the groups. The serum AgRP, leptin, and cholesterol levels were significantly different between the groups. The serum AgRP levels of manic group were significantly lower than those of euthymic and control groups. The lower serum AgRP levels of manic patients could be indicators of impaired energy homeostasis during manic episodes. Since the serum AgRP levels of manic patients are lower than those of euthymic patients and controls, AgRP could be a state marker for manic episodes.
Blocking of Estradiol Receptors ER alpha, ER beta and GPER During Development, Differentially Alters Energy Metabolism in Male and Female Rats
NEUROSCIENCE
Authors: Carrillo, Beatriz; Collado, Paloma; Diaz, Francisca; Chowen, Julie A.; Grassi, Daniela; Pinos, Helena
Abstract
Estradiol not only participates in the regulation of energy metabolism in adulthood, but also during the first stages of life as it modulates the alterations induced by under- and over-nutrition. The objectives of the present study were to determine: 1) If estradiol is involved in the normal programming of energy metabolism in rats; 2) If there is a specific window of time for this programming and 3) If males and females are differentially vulnerable to the action of this hormone. Estrogen receptors (ER) alpha, ER beta and GPER were blocked by their specific antagonists MPP, PHTPP and G15, respectively, from postnatal day (P) 1 (the day of birth) to P5 or from P5 to P13. Physiological parameters such as body weight, fat depots and caloric intake were then analysed at P90. Hypothalamic AgRP, POMC, MC4R, ER alpha, ER beta and GPER mRNA levels and plasma levels of estradiol, were also studied. We found that blocking ER receptors from P5 to P13 significantly decreases long-term body weight in males and hypothalamic POMC mRNA levels in females. The blocking of ERs from P1 to P5 only affected plasma estradiol levels in females. The present results indicate programming actions of estradiol from P5 to P13 on body weight in male and POMC expression in female rats and emphasize the importance of including both sexes in metabolic studies. It is necessary to unravel the mechanisms that underlie the actions of estradiol on food intake, both during development and in adulthood, and to determine how this programming differentially takes place in males and females. (C) 2019 IBRO. Published by Elsevier Ltd. All rights reserved.