Energy content of weight loss: kinetic features during voluntary caloric restriction

Energy restriction is a first therapy in the treatment of obesity, but the underlying biological mechanisms have not been completely clarified. We analyzed the effects of restriction of high-fat diet (HFD) on weight loss, circulating gut hormone levels and expression of hypothalamic neuropeptides. Ten-week-old male Wistar rats (n = 40) were randomly distributed into four groups: two fed ad libitum a normal diet (ND) (N group) or a HFD (H group) and two subjected to a 25% caloric restriction of ND (NR group) or HFD (HR group) for 9 weeks. A 25% restriction of HFD over 9 weeks leads to a 36% weight loss with regard to the group fed HFD ad libitum accompanied by normal values in adiposity index and food efficiency ratio (FER). This restriction also carried the normalization of NPY, AgRP and POMC hypothalamic mRNA expression, without changes in CART. Caloric restriction did not succeed in improving glucose homeostasis but reduced HFD-induced hyperinsulinemia. In conclusion, 25% restriction of HFD reduced adiposity and improved metabolism in experimental obesity, without changes in glycemia. Restriction of the HFD triggered the normalization of hypothalamic NPY, AgRP and POMC expression, as well as ghrelin and leptin levels.

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Weight loss in obese men by caloric restriction and high-dose diazoxide–mediated insulin suppression

Diabetes Obesity and Metabolism ◽

10.1111/j.1463-1326.2008.00878.x ◽

2008 ◽

Vol 0 (0) ◽

pp. 080512004419299-??? ◽

Cited By ~ 1

Author(s):

G. van Boekel ◽

S. Loves ◽

A. van Sorge ◽

J. Ruinemans-Koerts ◽

T. Rijnders ◽

...

Keyword(s):

Weight Loss ◽

Caloric Restriction ◽

High Dose

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Lower extremity muscle size and strength and aerobic capacity decrease with caloric restriction but not with exercise-induced weight loss

Journal of Applied Physiology ◽

10.1152/japplphysiol.00853.2006 ◽

2007 ◽

Vol 102 (2) ◽

pp. 634-640 ◽

Cited By ~ 111

Author(s):

Edward P. Weiss ◽

Susan B. Racette ◽

Dennis T. Villareal ◽

Luigi Fontana ◽

Karen Steger-May ◽

...

Keyword(s):

Weight Loss ◽

Caloric Restriction ◽

Aerobic Capacity ◽

Lean Mass ◽

Muscle Volume ◽

Muscle Size ◽

Thigh Muscle ◽

Physical Work ◽

Physical Work Capacity ◽

Exercise Induced

Caloric restriction (CR) results in fat loss; however, it may also result in loss of muscle and thereby reduce strength and aerobic capacity (V̇o2 max). These effects may not occur with exercise-induced weight loss (EX) because of the anabolic effects of exercise on heart and skeletal muscle. We tested the hypothesis that CR reduces muscle size and strength and V̇o2 max, whereas EX preserves or improves these parameters. Healthy 50- to 60-yr-old men and women (body mass index of 23.5–29.9 kg/m2) were studied before and after 12 mo of weight loss by CR ( n = 18) or EX ( n = 16). Lean mass was assessed by dual-energy X-ray absorptiometry, thigh muscle volume by MRI, isometric and isokinetic knee flexor strength by dynamometry, and treadmill V̇o2 max by indirect calorimetry. Both interventions caused significant decreases in body weight (CR: −10.7 ± 1.4%, EX: −9.5 ± 1.5%) and lean mass (CR: −3.5 ± 0.7%, EX: −2.2 ± 0.8%), with no significant differences between groups. Significant decreases in thigh muscle volume (−6.9 ± 0.8%) and composite knee flexion strength (−7.2 ± 3%) occurred in the CR group only. Absolute V̇o2 max decreased significantly in the CR group (−6.8 ± 2.3%), whereas the EX group had significant increases in both absolute (+15.5 ± 2.4%) and relative (+28.3 ± 3.0%) V̇o2 max. These data provide evidence that muscle mass and absolute physical work capacity decrease in response to 12 mo of CR but not in response to a similar weight loss induced by exercise. These findings suggest that, during EX, the body adapts to maintain or even enhance physical performance capacity.

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Whey Protein and Essential Amino Acids Promote the Reduction of Adipose Tissue and Increased Muscle Protein Synthesis During Caloric Restriction-Induced Weight Loss in Elderly, Obese Individuals

Clinical Nutrition and Aging ◽

10.1201/9781315364971-6 ◽

2017 ◽

pp. 69-86

Author(s):

Robert H. Coker ◽

Sharon Miller ◽

Scott Schutzler ◽

Nicolaas Deutz ◽

Robert R. Wolfe

Keyword(s):

Amino Acids ◽

Weight Loss ◽

Protein Synthesis ◽

Adipose Tissue ◽

Whey Protein ◽

Caloric Restriction ◽

Muscle Protein ◽

Muscle Protein Synthesis ◽

Essential Amino Acids

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Local Administration of Caloric Restriction Mimetics to Promote the Immune Control of Lung Metastases

Journal of Immunology Research ◽

10.1155/2019/2015892 ◽

2019 ◽

Vol 2019 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

Valentino Le Noci ◽

Michele Sommariva ◽

Francesca Bianchi ◽

Tiziana Triulzi ◽

Elda Tagliabue ◽

...

Keyword(s):

Weight Loss ◽

Caloric Restriction ◽

Lung Metastases ◽

Pcr Analysis ◽

Local Administration ◽

Antitumor Effects ◽

Lung Structure ◽

Collateral Effects ◽

M1 Phenotype

Caloric restriction mimetics (CRMs), compounds that mimic the biochemical effects of nutrient deprivation, administered via systemic route promote antitumor effects through the induction of autophagy and the modulation of the immune microenvironment; however, collateral effects due to metabolic changes and the possible weight loss might potentially limit their administration at long term. Here, we investigated in mice local administration of CRMs via aerosol to reduce metastasis implantation in the lung, whose physiologic immunosuppressive status favors tumor growth. Hydroxycitrate, spermidine, and alpha-lipoic acid, CRMs that target different metabolic enzymes, administered by aerosol, strongly reduced implantation of intravenously injected B16 melanoma cells without overt signs of toxicity, such as weight loss and changes in lung structure. Cytofluorimetric analysis of lung immune infiltrates revealed a significant increase of alveolar macrophages and CD103+ dendritic cells in mice treated with CRMs that paralleled an increased recruitment and activation of both CD3 T lymphocytes and NK cells. These effects were associated with the upregulation of genes related to M1 phenotype, as IL-12 and STAT-1, and to the decrease of M2 genes, as IL-10 and STAT-6, in adherent fraction of lung immune infiltrate, as revealed by real-time PCR analysis. Thus, in this proof-of-principle study, we highlight the antitumor effect of CRM aerosol delivery as a new and noninvasive therapeutic approach to locally modulate immunosurveillance at the tumor site in the lung.

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Experimental demonstration of human weight homeostasis: implications for understanding obesity

British Journal Of Nutrition ◽

10.1079/bjn20031051 ◽

2004 ◽

Vol 91 (3) ◽

pp. 479-484 ◽

Cited By ~ 21

Author(s):

Alejandro E. Macias

Keyword(s):

Weight Loss ◽

Body Weight ◽

Weight Gain ◽

Energy Expenditure ◽

Human Body ◽

Energy Content ◽

Energy Restriction ◽

Homeostatic Control ◽

Measurement Variability ◽

Set Point

The existence of a set-point for homeostatic control of human body weight is uncertain. To investigate its existence, technically difficult determinations of energy expenditure must be performed: this has resulted in contradictory reports. The present study was performed with new methods in two stages (77 and 133d respectively). Two healthy male subjects with rigorously controlled physical activity ingested three standardized diets of processed foods from the same manufacturer. Hypo-, iso- and hyperenergetic diets containing 6255kJ (1494kcal), 10073kJ (2406kcal) and 13791kJ (3294kcal) respectively were ingested during alternate periods; changes in body weight were measured. A new index of energy expenditure was calculated as the amount of weight lost in an 8h overnight period (WL8H). A digital scale was used in stage 1 and a mechanical scale in stage 2. The change in body weight in response to the isoenergetic diet differed according to the circumstances. In basal conditions, it was associated with weight stability. After weight loss from energy restriction, the isoenergetic diet led to weight gain. After weight gain from overeating, it led to weight loss. Diets of higher energy content were associated with greater WL8H (F>20; P<0·0001 for both subjects). Measurement variability was lower using a mechanical scale. The present study demonstrates the existence of a homeostatic control of human weight and describes a new index of energy expenditure measured in weight units. It also demonstrates that strict dietary supervision for months is possible. Investigation of the human body weight set-point is vital in understanding obesity.

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