). It has been proposed that while leptin is the main regulator of fasting induced changes in the HPT axis, deiodinase activity plays a major role during NTIS ( Boelen et al . 2011 ). Positive energy balance In contrast to the relatively detailed
Patricia Joseph-Bravo, Lorraine Jaimes-Hoy, Rosa-María Uribe, and Jean-Louis Charli
David R Broom, Masashi Miyashita, Lucy K Wasse, Richard Pulsford, James A King, Alice E Thackray, and David J Stensel
have witnessed significant research into the relationship between exercise, appetite regulation and energy balance ( Schubert et al. 2014 ). Exercise is recommended as a therapeutic weight management strategy because it increases energy expenditure
Tabata M Bohlen, Thais T Zampieri, Isadora C Furigo, Pryscila D S Teixeira, Edward O List, John J Kopchick, Jose Donato Jr, and Renata Frazao
-related peptide (AgRP) and proopiomelanocortin (POMC) neurons co-express LepR and are considered mediators of the energy balance status and HPG axis function ( Manfredi-Lozano et al. 2016 , Padilla et al. 2017 ). On the other hand, PMv neurons integrate
Amanda E Brandon, Ella Stuart, Simon J Leslie, Kyle L Hoehn, David E James, Edward W Kraegen, Nigel Turner, and Gregory J Cooney
. Diabetes 55 390 – 397 . ( doi:10.2337/diabetes.55.02.06.db05-0686 ) Ayala JE Bracy DP Julien BM Rottman JN Fueger PT Wasserman DH 2007 Chronic treatment with sildenafil improves energy balance and insulin action in high fat-fed conscious
Rumana Yasmeen, Qiwen Shen, Aejin Lee, Jacob H Leung, Devan Kowdley, David J DiSilvestro, Lu Xu, Kefeng Yang, Andrei Maiseyeu, Naresh C Bal, Muthu Periasamy, Paolo Fadda, and Ouliana Ziouzenkova
Introduction Leptin (LEP) is a critical hormone that regulates energy balance ( Friedman 2016 ). LEP is secreted primarily by adipose tissue and has been classified as an adipokine ( Friedman 2016 ). LEP functions are mediated by the LEP
P. M. Riis and A. Madsen
Plasma thyroxine (T4) concentrations were measured during pregnancy and lactation in goats on diets with different energy concentrations to study the role of T4 secretion in metabolic adaptation to pregnancy and lactation. Thyroxine distribution space (the volume of fluid required to dissolve the total pool of circulating T4 at a concentration equal to that in the plasma) and secretion rates were determined by using 125I-labelled T4 at different stages of lactation and pregnancy.
Plasma concentrations of T4 increased during lactation and reached maximum levels 4–5 months after giving birth. They then remained fairly constant for the following 2–3 months until the goats became pregnant again. Thyroxine concentrations decreased slightly during pregnancy and showed a sudden drop at the onset of lactation. Minimum concentrations were observed during the first 2–3 weeks of lactation after which time concentrations increased slowly. Average concentrations for goats on a low-energy diet were consistently lower than those in goats on a high-energy diet. The mean secretion rate was 10·4 nmol day−1 kg body wt−0·75. The distribution spaces were much lower than the total extracellular space. The average distribution space in non-pregnant and pregnant goats was 11 and 5·3% of the body weight respectively.
The decrease in T4 secretion rate and T4 distribution space during pregnancy is considered to be part of a homeorhetic adaptation to the condition. The drop in T4 secretion rate at the onset of lactation appears to be a homeostatic adaptation to a decreased fuel supply, similar to the situation with fasting or energy malnutrition.
J. Endocr. (1985) 107, 421–427
Franka S Schaebs, Tanja E Wolf, Verena Behringer, and Tobias Deschner
, Roff & Fairbairn 2007 , French et al. 2009 ). Monitoring an individual’s energy balance (defined as energy intake minus energy expenditure) is, therefore, essential to understanding how individuals allocate their energy between competing demands in
Michael Rosenbaum and Rudolph L Leibel
the hypometabolic state of the ob / ob and db / db mice. The observation of persistent hypometabolism following weight loss while in a state of energy balance was consistent with the so-called ‘lipostatic’ theory of body weight maintenance, which
Margaret B Allison and Martin G Myers Jr
important and widely studied players in the control of energy balance is the hormone leptin ( Friedman & Halaas 1998 , Elmquist et al . 2005 ). Leptin was discovered by Zhang et al . (1994) . Defects in leptin production underlie the massive obesity
Dawid Szczepankiewicz, Ewa Pruszynska-Oszmalek, Przemyslaw Kaczmarek, Marek Skrzypski, Karolina Andralojc, Tatiana Wojciechowicz, Maciej Sassek, and Krzysztof W Nowak
energy balance. It was found that AGRP expression is associated with changes in the leptin level, one of the main hormones which regulates food intake via the hypothalamus. It was further observed that AGRP is produced in neurons that exhibit leptin