scholarly journals OR01-5 Leptin Acts through Altering Energy Intake and Lipolysis to Reduce Body Weight but Has No Effect on Energy Expenditure, Physical Activity, and Sympathetic Nervous System in Humans

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Pavlina Chrysafi ◽  
Natia Peradze ◽  
Konstantinos Stefanakis ◽  
Eleni Pilitsi ◽  
Olivia Farr ◽  
...  
2003 ◽  
Vol 284 (4) ◽  
pp. E778-E787 ◽  
Author(s):  
Robert L. Dobbins ◽  
Lidia S. Szczepaniak ◽  
Weiguo Zhang ◽  
J. Denis McGarry

To assess the importance of the sympathetic nervous system in regulating body weight during prolonged leptin infusion, we evaluated food intake, body weight, and physical activity in conscious, unrestrained rats. Initial studies illustrated that prolonged intracerebroventricular (ICV) infusion of leptin enhanced substrate oxidation so that adipose tissue lipid stores were completely ablated, and muscle triglyceride and liver glycogen stores were depleted. After neonatal chemical sympathectomy, changes in weight and food intake were compared in groups of sympathectomized (SYM) and control (CON) adult animals during ICV infusion of leptin. CON animals lost 60 ± 9 g over 10 days vs. 25 ± 3 g in the SYM animals when food intake was matched between the two groups. Greater weight loss despite similar energy intake points to an important role of the sympathetic nervous system in stimulating energy expenditure during ICV leptin infusion by increasing the resting metabolic rate, since no differences in physical activity were observed between CON and SYM groups. In conclusion, activation of the SNS by leptin increases energy expenditure by augmenting the resting metabolic rate.


2020 ◽  
Vol 105 (4) ◽  
pp. 1145-1156 ◽  
Author(s):  
Tim Hollstein ◽  
Alessio Basolo ◽  
Takafumi Ando ◽  
Susanne B Votruba ◽  
Jonathan Krakoff ◽  
...  

Abstract Background Interindividual variability in 24-hour energy expenditure (24EE) during energy-balance conditions is mainly determined by differences in body composition and demographic factors. Previous studies suggested that 24EE might also be influenced by sympathetic nervous system activity via catecholamine (norepinephrine, epinephrine) secretion. Therefore, we analyzed the association between catecholamines and energy expenditure in 202 individuals from a heterogeneous population of mixed ethnicities. Methods Participants (n = 202, 33% female, 14% black, 32% white, 41% Native American, 11% Hispanic, age: 36.9 ± 10.3 y [mean ± SD], percentage body fat: 30.3 ± 9.4) resided in a whole-room calorimeter over 24 hours during carefully controlled energy-balance conditions to measure 24EE and its components: sleeping metabolic rate (SMR), awake-fed thermogenesis (AFT), and spontaneous physical activity (SPA). Urine samples were collected, and 24-h urinary epinephrine and norepinephrine excretion rates were assessed by high-performance liquid chromatography. Results Both catecholamines were associated with 24EE and SMR (norepinephrine: +27 and +19 kcal/d per 10 μg/24h; epinephrine: +18 and +10 kcal/d per 1 μg/24h) in separate analyses after adjustment for age, sex, ethnicity, fat mass, fat-free mass, calorimeter room, temperature, and physical activity. In a multivariate model including both norepinephrine and epinephrine, only norepinephrine was independently associated with both 24EE and SMR (both P < .008), whereas epinephrine became insignificant. Neither epinephrine nor norepinephrine were associated with adjusted AFT (both P = .37) but epinephrine was associated with adjusted SPA (+0.5% per 1 μg/24h). Conclusions Our data provide compelling evidence that sympathetic nervous system activity, mediated via norepinephrine, is a determinant of human energy expenditure during nonstressed, eucaloric conditions.


1991 ◽  
Vol 261 (6) ◽  
pp. E789-E794 ◽  
Author(s):  
M. F. Saad ◽  
S. A. Alger ◽  
F. Zurlo ◽  
J. B. Young ◽  
C. Bogardus ◽  
...  

The impact of sympathetic nervous system (SNS) activity on energy expenditure (EE) was evaluated in nondiabetic Caucasian and Pima Indian men while on a weight-maintenance diet using two approaches as follows. 1) The relationship between 24-h EE, measured in a respiratory chamber, and 24-h urinary norepinephrine was studied in 36 Caucasians [32 +/- 8 (SD) yr, 95 +/- 41 kg, 22 +/- 13% fat] and 33 Pimas (29 +/- 6 yr, 103 +/- 28 kg, 30 +/- 9% fat). There was no difference between the two groups in 24-h EE (2,422 vs. 2,523 kcal/24 h) and in urinary norepinephrine (28 vs. 31 micrograms/24 h), even after adjusting for body size and composition. Twenty-four-hour EE correlated significantly with 24-h urinary norepinephrine in Caucasians (r = 0.78, P less than 0.001) but not in Pimas (r = 0.03), independent of fat-free mass (FFM), fat mass, and age. 2) The effect of beta-adrenoceptor blockade with propranolol (120 micrograms/kg FFM bolus and 1.2 micrograms.kg FFM-1.min-1 for 45 min) on the resting metabolic rate (RMR) was evaluated in 36 Caucasians (30 +/- 6 yr, 103 +/- 36 kg, 25 +/- 11% fat) and 32 Pimas (28 +/- 6 yr, 100 +/- 34 kg, 27 +/- 10% fat). The RMR was similar in the two groups (2,052 vs. 1,973 kcal/24 h) even after adjustment for FFM, fat mass, and age and dropped significantly after propranolol infusion in Caucasians (-3.9%, P less than 0.001) but not in Pimas (-0.8%, P = 0.07).(ABSTRACT TRUNCATED AT 250 WORDS)


2010 ◽  
Vol 2010 ◽  
pp. 1-7 ◽  
Author(s):  
Russell Rising ◽  
Gul Tiryaki Sonmez

Background. Malnourished infants are small for age and weight.Objectives. Determine profiles in 24-hour energy metabolism in recovering malnourished infants and compare to similarly aged healthy controls.Methods. 10 malnourished infants (58.1±5.9 cm,7.7±5.6months) were healthy prior to spending 22 hours in the Enhanced Metabolic Testing Activity Chamber for measurement of EE (kcal/min), sleeping metabolic rate (SMR; kcal/min), respiratory quotient (RQ;VCO2/VO2), and physical activity (PA; oscillations in wt/min/kg body weight). Metabolic data were extrapolated to 24 hours (kcal/kg/d). Energy intake (kcal/kg/d) and the proportions (%) of carbohydrate, protein, and fat were calculated. Anthropometrics for malnourished infants were obtained. Statistical differences (P<.05) between groups were determined (SPSS, version 13).Results. In comparison to controls, malnourished infants were lighter (4.1±1.2versus7.3±0.8 kg;P<.05), had less body fat % (10.3±7.6versus25.7±2.5), and lower BMI (12.0±1.7versus15.5±1.5;P<.05). In contrast, they had greater energy intake (142.7±14.6versus85.1±25.8;P<.05) with a greater percentage of carbohydrates (55.1±3.9versus47.2±5.2;P<.05). However, malnourished infants had greater 24-hour EE (101.3±20.1versus78.6±8.4;P<.05), SMR (92.6±17.1versus65.0±3.9;P<.05), and RQ (1.00±0.13versus0.86±0.08;P<.05) along with a lower amount of PA (2.3±0.94versus4.0±1.5;P<.05).Conclusions. Malnourished infants require more energy, possibly for growth.


Author(s):  
Surabhi Bhutani ◽  
Jamie A Cooper ◽  
Michelle R Vandellen

ABSTRACTBackgroundThe COVID-19 pandemic has caused people to shelter-at-home for an extended period, resulting in a sudden rise in unstructured time. This unexpected disruption in everyday life has raised concerns about weight management, especially in high-risk populations of women and individuals with overweight and obesity. This study aimed to investigate the changes in behaviors that may impact energy intake and/or energy expenditure in U.S. adults during the home confinement.MethodsCross-sectional data from 1,779 adults were collected using an online Qualtrics survey between April 24th and May 4th, 2020. Self-reported data on demographics, eating behaviors, physical activity, sleep, screen time, takeout food intake, and food purchasing behaviors were collected. Chi-Square analyses were conducted to evaluate differences in the percent of participants reporting increasing, decreasing, or staying the same in each health behavior since the COVID-19 outbreak in their area. Each analysis was followed by comparing whether increases or decreases were more likely for each health behavior. Similar comparisons were made between male and female participants and between body mass index (BMI) categories.ResultsWe observed an increase in the intake of both healthy and energy-dense unhealthy foods and snacks during the home confinement. Participants also reported increases in sedentary activities and decrease in physical activity, alcohol intake, and consumption of takeout meals during this time. In women, several behavioral changes support greater energy intake and less energy expenditure than men. No clear difference in patterns was observed across BMI status.ConclusionAcute changes in behaviors underscore the significance of a sudden increase in unstructured time at home on potential weight gain. Our findings support the need to implement and support measures that promote strategies to maintain body weight and establish a methodology to collect body weight data at multiple time points to longitudinally assess the dynamic relationship between behaviors and body weight change.


2021 ◽  
Vol 12 (4) ◽  
Author(s):  
Xiao-Hong Zhang ◽  
Ling-Yun Tang ◽  
Xi-Yi Wang ◽  
Chun-Ling Shen ◽  
Wen-Feng Xiong ◽  
...  

AbstractAdhesion G protein-coupled receptor A1 (ADGRA1, also known as GPR123) belongs to the G protein-coupled receptors (GPCRs) family and is well conserved in the vertebrate lineage. However, the structure of ADGRA1 is unique and its physiological function remains unknown. Previous studies have shown that Adgra1 is predominantly expressed in the central nervous system (CNS), indicating its important role in the transduction of neural signals. The aim of this study is to investigate the central function of Adgra1 in vivo and clarify its physiological significance by establishing an Adgra1-deficient mouse (Adgra1−/−) model. The results show that Adgra1−/− male mice exhibit decreased body weight with normal food intake and locomotion, shrinkage of body mass, increased lipolysis, and hypermetabolic activity. Meanwhile, mutant male mice present elevated core temperature coupled with resistance to hypothermia upon cold stimulus. Further studies show that tyrosine hydroxylase (TH) and β3-adrenergic receptor (β3-AR), indicators of sympathetic nerve excitability, are activated as well as their downstream molecules including uncoupling protein 1 (UCP1), coactivator 1 alpha (PGC1-α) in brown adipose tissue (BAT), and hormone-sensitive lipase (HSL) in white adipose tissue (WAT). In addition, mutant male mice have higher levels of serum T3, T4, accompanied by increased mRNAs of hypothalamus–pituitary–thyroid axis. Finally, Adgra1−/− male mice present abnormal activation of PI3K/AKT/GSK3β and MEK/ERK pathways in hypothalamus. Overexpression of ADGRA1 in Neuro2A cell line appears to suppress these two signaling pathways. In contrast, Adgra1−/− female mice show comparable body weight along with normal metabolic process to their sex-matched controls. Collectively, ADGRA1 is a negative regulator of sympathetic nervous system (SNS) and hypothalamus–pituitary–thyroid axis by regulating PI3K/AKT/GSK3β and MEK/ERK pathways in hypothalamus of male mice, suggesting an important role of ADGRA1 in maintaining metabolic homeostasis including energy expenditure and thermogenic balance.


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