scholarly journals Leptin Responsiveness in Chronically Decerebrate Rats

Endocrinology ◽  
2007 ◽  
Vol 148 (10) ◽  
pp. 4623-4633 ◽  
Author(s):  
Ruth B. S. Harris ◽  
Timothy J. Bartness ◽  
Harvey J. Grill
Keyword(s):  
Energy Expenditure ◽  
Body Fat ◽  
Serum Testosterone ◽  
Control Group ◽  
Energy Status ◽  
Lower Serum ◽  
Peripheral Tissues ◽  
Leptin Receptors ◽  
Ad Libitum ◽  
Ad Libitum Intake

Peripheral infusions of physiological doses of leptin decrease body fat mass, but it is not known whether this results from direct effects on peripheral tissue or activation of central leptin receptors. In this study, we infused chronically decerebrate (CD) rats, in which the forebrain was surgically isolated from the caudal brainstem, with 60 μg leptin/d or PBS for 14 d from ip mini-osmotic pumps. The CD rats were tube fed an amount of food equivalent to the intake of ad libitum-fed intact controls or 75% of this amount to account for their reduced energy expenditure. Control rats fed ad libitum or tube fed 75, 100, or 125% of their ad libitum intake also were peripherally infused with leptin or PBS. CD rats had a lower serum testosterone, energy expenditure, and lean body mass compared with controls but had increased levels of adiponectin and leptin and were obese. Leptin increased body fat and decreased energy expenditure during the light period in 100%-fed CD rats, but not 75%-fed CD rats. Leptin decreased body fat of ad libitum- and 100%-fed but not 75%-fed or 125%-fed intact controls. Energy expenditure did not change in any control group. These results show that leptin can change body fat independent of a change in food intake or energy expenditure, that the forebrain normally prevents leptin from inhibiting energy expenditure through mechanisms initiated in the caudal brainstem or peripheral tissues, and that the leptin response in both intact and CD rats is determined by the energy status of the animal.

scholarly journals Effect of ad libitum intake of an electrolyte repository in horses that underwent a polo game

2018 ◽  
Vol 39 (1) ◽  
pp. 187
Author(s):  
Lorena Chaves Monteiro ◽  
José Dantas Ribeiro Filho ◽  
Waleska De Melo Ferreira Dantas ◽  
Bruna Maria Ribeiro ◽  
Micheline Ozana da Silva ◽  
...  
Keyword(s):  
Cell Volume ◽  
Packed Cell Volume ◽  
Chloride Concentration ◽  
Control Group ◽  
Significance Level ◽  
Group Water ◽  
Calcium Magnesium ◽  
Ad Libitum ◽  
Ad Libitum Intake ◽  
And Control

The objective of this study was to assess the effects of an electrolyte and energy repository on the hematologic and biochemical variables of horses after a polo game and compare them to the effects of a commercial electrolyte repository and water. Twelve healthy horses, aged 5 to 10 years, mean body weight 356.25 ± 25.6 kg and in training for polo games, were randomly divided into three groups of four animals each and received one of three treatments. Animals participated in a 7-minute polo game. At the end of the match, they were taken to individual stalls where they received treatments for spontaneous hydration for 6 hours. Treatments were Hydroelectrolytic and Energy Repository (RHE) containing sodium, chloride, potassium, calcium, magnesium, dextrose, maltodextrin and, sucrose; and Commercial Paste (PCO) containing calcium, fructooligosaccharides, glycine, magnesium, potassium, sodium, and ad libitum water. The control group (Water) received water. Blood samples were collected as follows: just before the beginning of exercise (T0), immediately after exercise (T1), 3 hours after the end of exercise (T3), and 6 hours after the end of exercise (T6). The volume of voluntary intake was measured at T3 and T6. Packed cell volume and serum concentrations of sodium, potassium, chloride, calcium, magnesium, phosphorus, creatinine, total protein, plasma glucose, and lactate were measured. Data were submitted to descriptive statistics (mean ± standard deviation), Lilliefors and Cochran & Bartlett tests, analysis of variance (ANOVA), and Tukey or Duncan tests at a 5% significance level. The net volume ingested by the RHE group was higher than the PCO and control groups. In all groups, a reduction in chloride concentration and increases in packed cell volume, protein, creatinine, glucose, and lactate concentrations were observed in T1. These variables returned to the values found at T0 throughout the rehydration phase (T3 and T6). It is concluded that the ingestion of the hydroelectrolytic energy repository does not cause alteration in the biochemical profile of the animals.

scholarly journals Energy Status and Body Composition Across a Collegiate Women’s Lacrosse Season

Nutrients ◽  
2019 ◽  
Vol 11 (2) ◽  
pp. 470 ◽  
Author(s):  
Hannah Zabriskie ◽  
Bradley Currier ◽  
Patrick Harty ◽  
Richard Stecker ◽  
Andrew Jagim ◽  
...  
Keyword(s):  
Body Composition ◽  
Energy Expenditure ◽  
Body Fat ◽  
Resting Metabolic Rate ◽  
Negative Energy ◽  
Macronutrient Intake ◽  
Energy Status ◽  
Fat Percentage ◽  
Energy Expenditures ◽  
Total Daily Energy Expenditure

Little data is available regarding the energy and nutritional status of female collegiate team sport athletes. Twenty female NCAA Division II lacrosse athletes (mean ± SD: 20.4 ± 1.8 years; 68.8 ± 8.9 kg; 168.4 ± 6.6 cm; 27.9 ± 3% body fat) recorded dietary intake and wore a physical activity monitor over four consecutive days at five different time points (20 days total) during one academic year. Body composition, bone health, and resting metabolic rate were assessed in conjunction with wearing the monitor during off-season, pre-season, and season-play. Body fat percentage decreased slightly during the course of this study (p = 0.037). Total daily energy expenditure (TDEE) (p < 0.001) and activity energy expenditure (AEE) (p = 0.001) energy were found to change significantly over the course of the year, with pre-season training resulting in the highest energy expenditures (TDEE: 2789 ± 391 kcal/day; AEE: 1001 ± 267 kcal/day). Caloric (2124 ± 448 kcal/day), carbohydrate (3.6 ± 1.1 g/kg), and protein (1.2 ± 0.3 g/kg) intake did not change over the course of the year (p > 0.05). Athletes self-reported a moderate negative energy balance (366–719 kcal/day) and low energy availability (22.9–30.4 kcal/kg FFM) at each measurement period throughout the study. Reported caloric and macronutrient intake was low given the recorded energy expenditure and macronutrient intake recommendations for athletes. Athletic support staff should provide athletes with appropriate fueling strategies, particularly during pre-season training, to adequately meet energy demands.

Feed utilization, energy expenditure and nitrogen metabolism in working female buffaloes (Bubalus bubalis)

1991 ◽  
Vol 42 (8) ◽  
pp. 1359
Author(s):  
E Teleni ◽  
R Pieterson ◽  
G De'ath
Keyword(s):  
Amino Acids ◽  
Organic Matter ◽  
Energy Expenditure ◽  
Rice Straw ◽  
Nitrogen Balance ◽  
Muscular Activity ◽  
Feed Utilization ◽  
Entry Rate ◽  
Ad Libitum ◽  
Ad Libitum Intake

Four 36-months-old female buffaloes, with a mean liveweight of 345 kg, were used in a study designed to estimate the effect of work (3 h/day) on feed utilization, energy expenditure and nitrogen metabolism. The animals were studied under ambient temperatures and relative humidities ranging from 25.3 to 32.5'C and 45 to 82% respectively, and were fed rice straw (0.8% nitrogen) ad libitum, supplemented with cottonseed meal at 500 g head-1 day-1 to result in a dietary nitrogen content of 1.15%. Work did not affect the digestibility of the feed but tended to reduce (P=0.054) ad libitum intake of its organic matter. Rectal temperatures and respiration rates were increased during work from 37.7 to a peak of 40.8�C and from 40 to a peak of 130 counts/min respectively. The ratio of working : resting metabolic rate, as calculated from CO2 entry rates, was approximately 2.6. Estimates of energy expenditures from CO2 entry rates showed increases in the working animal by 2.3 to 2.7 times the resting values. Nitrogen balance was reduced in the working animal owing to increased catabolism of amino acids and the resultant increased excretion of urea via the urine. Urea entry rate was increased in the working animal, but the proportion of this that was estimated to be transferred to the digestive tract was not different from that in the non-working animal, although the amount transferred was greater in the working animal. It is suggested that increased muscular activity in the working animal would tend to reduce ad libitum intake of organic matter of a roughage such as rice straw, but could increase digestibility of organic matter possibly through reduction in the rate of passage of digesta and/or through increased amount of urea transferred to the rumen containing lower than an optimal level of ammonia. The increased catabolism of amino acids associated with increased muscular activity is likely to result in a reduced nitrogen balance due to the likely increased urea excretion via the urine. It is also suggested that CO2 entry rate could offer a reasonable estimate of energy expenditure in the resting and the working animal.

scholarly journals Iron Deficiency and Neuroendocrine Regulators of Basal Metabolism, Body Composition and Energy Expenditure in Rats

Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 631 ◽  
Author(s):  
Jorge Moreno-Fernandez ◽  
Javier Díaz-Castro ◽  
María Alférez ◽  
Inmaculada López-Aliaga
Keyword(s):  
Body Composition ◽  
Energy Expenditure ◽  
Body Fat ◽  
Lean Mass ◽  
Adrenocorticotropic Hormone ◽  
Iron Status ◽  
Basal Metabolism ◽  
Fe Deficiency ◽  
Control Group ◽  
Inverse Association

Although dietary iron is a determinant of iron status in animals, body fat mass has been reported to have an inverse association with iron status in human studies. The goal of this study was to determine the relationship between Fe homeostasis, body composition, energy expenditure and neuroendocrine regulators for severe Fe-deficiency anaemia. Forty male Wistar albino rats recently weaned were divided at random into two groups: the control group was fed the basal diet, AIN-93G diet (normal-Fe) and the anaemic group received a low-Fe diet for 40 days. Neuroendocrine parameters that regulate basal metabolism and appetite (thyroid hormones, ghrelin, glucose-dependent insulinotropic polypeptide (GIP), glucagon, insulin, adrenocorticotropic hormone and corticosterone), body composition, respiratory volumes, energy expenditure, haematological and biochemical were assessed. Total body fat was lower, whereas lean mass, free and total water were higher in the anemic group. O2 consumption, CO2 production, energy expenditure (EE) and respiratory quotient (RQ) were lower in the Fe-deficient animals. Triiodothyronine and thyroxine hormones decreased, while thyroid-stimulating hormone increased in the anemic group. Circulating levels of ghrelin were lower in the anemic group, while GIP, glucagon, insulin, corticosterone and adrenocorticotropic hormone levels were higher. Fe-deficiency impairs weight gain in the rats, with marked reductions in lean mass and body fat, indicating lower energy stores.

Malnutrition during the postnuptial molt of White-crowned Sparrows: feather growth and quality

1988 ◽  
Vol 66 (6) ◽  
pp. 1403-1413 ◽  
Author(s):  
Mary E. Murphy ◽  
James R. King ◽  
Jianjian Lu
Keyword(s):  
Control Group ◽  
Free Living ◽  
Zonotrichia Leucophrys ◽  
Balanced Diet ◽  
Feather Growth ◽  
Ad Libitum ◽  
Zonotrichia Leucophrys Gambelii ◽  
The Times ◽  
Ad Libitum Intake ◽  
Time Required

It has often been alleged that avian molt can be interrupted or delayed by food deprivation or malnutrition. We examined this experimentally in captive White-crowned Sparrows (Zonotrichia leucophrys gambelii). Beginning either at the natural onset of postnuptial molt or 1 month before its onset, groups of birds were fed either inadequate amounts of a balanced diet (60 or 80% of the ad libitum intake of a control group) or unlimited amounts of a diet deficient only in cyst(e)ine and methionine. Except in the 60% premolt group, the malnourished birds did not postpone or interrupt molt in spite of losses ranging from 20 to 38% of initial body mass. Molt was significantly protracted in all except the 60% premolt group as a result of both increased shedding interval and decreased feather growth rates. Their new plumage weighed less than that of control birds, and their remiges were slightly shorter and often deformed or achromatic. The occurrence of fault bars corresponded to the times when the birds were handled, but was not correlated with other plumage defects. Surviving birds of the 60% premolt group did not molt until allowed to feed ad libitum, but then produced a normal plumage in about two-thirds of the time required by the controls. To summarize, molt is a very conservative aspect of self maintenance that is distorted only by planes of malnutrition that free-living sparrows either do not encounter during the summer or do not survive.

Role of corticosterone in adaptive changes in energy expenditure during refeeding after low calorie intake

1990 ◽  
Vol 259 (5) ◽  
pp. E658-E664 ◽  
Author(s):  
A. G. Dulloo ◽  
J. Seydoux ◽  
L. Girardier
Keyword(s):  
Energy Expenditure ◽  
Energy Conservation ◽  
Food Consumption ◽  
Body Fat ◽  
Energy Utilization ◽  
Metabolic Adaptation ◽  
Calorie Intake ◽  
Control Group ◽  
Body Protein ◽  
Low Calorie

We examined the importance of corticosterone in elevated efficiency of energy utilization during refeeding after low food consumption. Energy balance studies during refeeding (over periods of 14 or 16 days) were conducted in rats previously food restricted for 16 days at 50% of normal food intake. Comparisons made with nonrestricted weight-matched controls after validation studies indicated that 2-wk-younger weight-matched controls had similar maintenance energy requirements and similar efficiency of energy utilization above maintenance (i.e., net efficiency) to nonrestricted age-matched controls. Results indicate that relative to controls refeeding after low food consumption was associated with enhanced energy conservation underlain by a 16-18% reduction (P less than 0.001) in total energy expenditure over a 14-day period. This metabolic adaptation for energy conservation resulted in a threefold increase (P less than 0.001) in body fat accretion but no difference in body protein deposition. Bilateral adrenalectomy (ADX) 2 days before refeeding reduced differences in energy expenditure between refed group and controls from 18 to 8% (P less than 0.01) and attenuated body fat gain from a three- to twofold increase (P less than 0.001) above control group. Effects of ADX were prevented by daily corticosterone replacement. Data suggest that after a period of low calorie intake an adaptive neurohormonal switching mechanism facilitates replenishment of fat stores during refeeding. This metabolic reorientation (characterized by an adaptive fall in energy expenditure) has both an adrenal as well as a nonadrenal component, because it is partially reversed by prior bilateral ADX, an effect attributed to removal of corticosterone-induced inhibition of thermogenesis.

scholarly journals Energy metabolism of young rats after early postnatal overnutrition

2002 ◽  
Vol 88 (3) ◽  
pp. 301-306 ◽  
Author(s):  
Petra Wiedmer ◽  
Sylvia Ortmann ◽  
Susanne Klaus
Keyword(s):  
Energy Metabolism ◽  
Energy Expenditure ◽  
Body Fat ◽  
Later Life ◽  
Daily Energy Intake ◽  
Daily Energy ◽  
Total Daily Energy Expenditure ◽  
Ad Libitum ◽  
Total Fat ◽  
The Relationship

Early postnatal overnutrition (PNO) induced by restricting litter size in rats leads to increased body-weight (BW) and body-fat gain in later life. PNO rats are used as an animal model of moderate obesity and early hyperinsulinism. We investigated whether the increased adiposity could be due to a decreased energy expenditure. Male newborn Wistar rats were raised in litters of either two (SL) or twelve pups (NL), weaned at 4 weeks of age and subsequently fed ad libitum. BW was recorded continuously until 12 weeks of age. Daily energy intake, total daily energy expenditure (EE, measured by indirect calorimetry) and body composition were measured in weaned pups at 5, 8 and 12 weeks of age. SL rats displayed increased BW compared with NL rats from week 2 to 5 and again from week 10 to 12. Lean body mass, body fat and protein content and total EE were increased in SL rats at week 5. The same linear correlation described the relationship between BW and total EE in NL and SL rats. At week 8 to 12 no differences in energy metabolism could be found, but the total fat content was increased in SL rats at week 12. Energy balance, i.e. assimilated energy minus EE, was no different between SL and NL at any time that it was measured. We conclude that although PNO rats display increased adiposity in early life, there seem to be no long-lasting effects on energy metabolism in later life, even if a tendency to increased adiposity can still be detected.

scholarly journals Alterations in energy balance from an exercise intervention with ad libitum food intake

2016 ◽  
Vol 5 ◽  
Author(s):  
Katarina Melzer ◽  
Anne Renaud ◽  
Stefanie Zurbuchen ◽  
Céline Tschopp ◽  
Jan Lehmann ◽  
...  
Keyword(s):  
Body Composition ◽  
Energy Balance ◽  
Energy Expenditure ◽  
Body Mass ◽  
Cardiorespiratory Fitness ◽  
Exercise Intervention ◽  
Intervention Group ◽  
Control Group ◽  
Anthropometric Measures ◽  
Ad Libitum

AbstractBetter understanding is needed regarding the effects of exercise alone, without any imposed dietary regimens, as a single tool for body-weight regulation. Thus, we evaluated the effects of an 8-week increase in activity energy expenditure (AEE) on ad libitum energy intake (EI), body mass and composition in healthy participants with baseline physical activity levels (PAL) in line with international recommendations. Forty-six male adults (BMI = 19·7–29·3 kg/m2) participated in an intervention group, and ten (BMI = 21·0–28·4 kg/m2) in a control group. Anthropometric measures, cardiorespiratory fitness, EI, AEE and exercise intensity were recorded at baseline and during the 1st, 5th and 8th intervention weeks, and movement was recorded throughout. Body composition was measured at the beginning and at the end of the study, and resting energy expenditure was measured after the study. The intervention group increased PAL from 1·74 (se 0·03) to 1·93 (se 0·03) (P < 0·0001) and cardiorespiratory fitness from 41·4 (se 0·9) to 45·7 (se 1·1) ml O2/kg per min (P = 0·001) while decreasing body mass (−1·36 (se 0·2) kg; P = 0·001) through adipose tissue mass loss (ATM) (−1·61 (se 0·2) kg; P = 0·0001) compared with baseline. The control group did not show any significant changes in activity, body mass or ATM. EI was unchanged in both groups. The results indicate that in normal-weight and overweight men, increasing PAL from 1·7 to 1·9 while keeping EI ad libitum over an 8-week period produces a prolonged negative energy balance. Replication using a longer period (and/or more intense increase in PAL) is needed to investigate if and at what body composition the increase in AEE is met by an equivalent increase in EI.

scholarly journals In vivo evidence for unidentified leptin-induced circulating factors that control white fat mass

2015 ◽  
Vol 309 (12) ◽  
pp. R1499-R1511 ◽  
Author(s):  
Ruth B. S. Harris
Keyword(s):  
Cell Size ◽  
Body Fat ◽  
Fat Mass ◽  
Leptin Receptor ◽  
Recipient Mouse ◽  
Body Fat Mass ◽  
Energy Status ◽  
Wild Type ◽  
Cell Size Distribution ◽  
Leptin Receptors

Fat transplants increase body fat mass without changing the energy status of an animal and provide a tool for investigating control of total body fat. Early transplant studies found that small pieces of transplanted fat took on the morphology of the transplant recipient. Experiments described here tested whether this response was dependent upon expression of leptin receptors in either transplanted fat or the recipient mouse. Fat from leptin receptor deficient db/db mice or wild-type mice was placed subcutaneously in db/db mice. After 12 wk, cell size distribution in the transplant was the same as in endogenous fat of the recipient. Thus, wild-type fat cells, which express leptin receptors, were enlarged in a hyperleptinemic environment, indicating that leptin does not directly control adipocyte size. By contrast, db/db or wild-type fat transplanted into wild-type mice decreased in size, suggesting that a functional leptin system in the recipient is required for body fat mass to be controlled. In the final experiment, wild-type fat was transplanted into a db/db mouse parabiosed to either another db/db mouse to an ob/ob mouse or in control pairs in which both parabionts were ob/ob mice. Transplants increased in size in db/db–db/db pairs, decreased in db/db–ob/ob pairs and did not change in ob/ob-ob/ob pairs. We propose that leptin from db/db parabionts activated leptin receptors in their ob/ob partners. This, in turn, stimulated release of unidentified circulating factors, which travelled back to the db/db partner and acted on the transplant to reduce fat cell size.

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