scholarly journals Caloric Restriction Prevents Metabolic Dysfunction and the Changes in Hypothalamic Neuropeptides Associated with Obesity Independently of Dietary Fat Content in Rats

Nutrients ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 2128
Author(s):  
Marina Martín ◽  
Amaia Rodríguez ◽  
Javier Gómez-Ambrosi ◽  
Beatriz Ramírez ◽  
Sara Becerril ◽  
...  

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.

2019 ◽  
Author(s):  
Margaret L Westwater ◽  
Flavia Mancini ◽  
Jane Shapleske ◽  
Jaco Serfontein ◽  
Monique Ernst ◽  
...  

Background: Anorexia nervosa (AN) and bulimia nervosa (BN) are complex psychiatric conditions, in which both psychological and metabolic factors have been implicated. Critically, the experience of stress can precipitate loss-of-control eating in both conditions, suggesting an interplay between mental state and metabolic signaling. However, associations between psychological states, symptoms and metabolic processes in AN and BN have not been examined. Methods: Eighty-five women (n=22 AN binge/purge subtype, n=33 BN, n=30 controls) underwent remote salivary cortisol sampling and a two-day, inpatient study session to examine the effect of stress on cortisol, gut hormones (acyl-ghrelin, PYY, GLP-1) and food consumption. Participants were randomized to either an acute stress induction or control task on each day, and plasma hormones were serially measured before a naturalistic, ad libitum meal.Results: Cortisol awakening response (CAR) was augmented in AN but not BN relative to controls, with body mass index explaining the most variance in CAR (36%). Acute stress increased acyl-ghrelin and PYY in AN compared to controls; however, stress did not alter gut hormone profiles in BN. Instead, a group-by-stress interaction showed nominally reduced cortisol reactivity in BN, but not AN, compared to controls. Ad libitum consumption was lower in both patient groups and unaffected by stress.Conclusions: Findings extend previous reports of metabolic dysfunction in binge-eating disorders, identifying unique associations across disorders and under stress. Moreover, we observed disrupted homeostatic signaling in AN following psychological stress, which may explain, in part, the maintenance of dysregulated eating in this serious illness.


2020 ◽  
Vol 106 (1) ◽  
pp. e204-e216
Author(s):  
Conor F Murphy ◽  
Nicholas Stratford ◽  
Neil G Docherty ◽  
Brendan Moran ◽  
Jessie A Elliott ◽  
...  

Abstract Background Recurrence-free patients after esophageal cancer surgery face long-term nutritional consequences, occurring in the context of an exaggerated postprandial gut hormone response. Acute gut hormone suppression influences brain reward signaling and eating behavior. This study aimed to suppress gut hormone secretion and characterize reward responses and eating behavior among postesophagectomy patients with unintentional weight loss. Methods This pilot study prospectively studied postoperative patients with 10% or greater body weight loss (BWL) beyond 1 year who were candidates for clinical treatment with long-acting octreotide (LAR). Before and after 4 weeks of treatment, gut hormone secretion, food cue reactivity (functional magnetic resonance imaging), eating motivation (progressive ratio task), ad libitum food intake, body composition, and symptom burden were assessed. Results Eight patients (7 male, age: mean ± SD 62.8 ± 9.4 years, postoperative BWL: 15.5 ± 5.8%) participated. Octreotide LAR did not significantly suppress total postprandial plasma glucagon-like peptide-1 response at 4 weeks (P = .08). Postprandial symptom burden improved after treatment (Sigstad score median [range]: 12 [2-28] vs 8 [3-18], P = .04) but weight remained stable (pre: 68.6 ± 12.8 kg vs post: 69.2 ± 13.4 kg, P = .13). There was no significant change in brain reward system responses, during evaluation of high-energy or low-energy food pictures, nor their appeal rating. Moreover, treatment did not alter motivation to eat (P = .41) nor ad libitum food intake(P = .46). Conclusion The protocol used made it feasible to characterize the gut-brain axis and eating behavior in this cohort. Inadequate suppression of gut hormone responses 4 weeks after octreotide LAR administration may explain the lack of gut-brain pathway alterations. A higher dose or shorter interdose interval may be required to optimize the intervention.


2021 ◽  
Author(s):  
Michelle Sabino de Souza Nunes Faria ◽  
Vinicius Eduardo Pimentel ◽  
Julia Venturini Helaehil ◽  
Mayara Correa Bertolo ◽  
Nathalia Tonus Horas Santos ◽  
...  

Background: Caloric restriction (CR) is a type of dietary intervention enjoyed as an essential tool in weight loss by modulating critical pathways of metabolic control, although it is not yet clear what repercussions this intervention model results when associated with renovascular hypertension. Here we demonstrate that CR can be beneficial in obese and hypertensive animals. Methods: Rats were divided into groups: SHAM, and two groups underwent surgery to clip the left renal artery, to induce renovascular hypertension (OH and OHR). The SHAM diet was performed: 14 weeks normolipidic diet; OH: 2 weeks normolipidic diet + 12 weeks hyperlipidic diet, both ad libitum; OHR: 2 weeks normolipidic diet + 8 weeks ad libitum high fat diet + 4 weeks restricted 40% high fat diet. Results: the OHR group dissipated blood pressure, body weight and glucose homeostasis. Reductions in insulinemia, lipids, islets fibrotic areas in the OHR group were observed along with increased insulin sensitivity and normalization of the insulin-degrading enzyme. Nicotinamide phosphoribosyltransferase, insulin receptor, Sirtuin 1 and complex II protein were modulated in liver tissue in the OHR group. Strong correlations, direct or indirect, were evaluated by Spearmans model between SIRT1, AMPK, NAMPT, PGC-[alpha]; and NNMT with the reestablishment of blood pressure, weight loss, glycidic and lipid panel and mitochondrial adaptation. Conclusion: CR provided short-term beneficial effects to recover physiological parameters induced by a high-fat diet and renal artery stenosis in obese and hypertensive animals. These benefits, even in the short term, can bring physiological benefits in the long run.


2020 ◽  
pp. 1-11 ◽  
Author(s):  
Margaret L. Westwater ◽  
Flavia Mancini ◽  
Jane Shapleske ◽  
Jaco Serfontein ◽  
Monique Ernst ◽  
...  

Abstract Background Anorexia nervosa (AN) and bulimia nervosa (BN) are complex psychiatric conditions, in which both psychological and metabolic factors have been implicated. Critically, the experience of stress can precipitate loss-of-control eating in both conditions, suggesting an interplay between mental state and metabolic signaling. However, associations between psychological states, symptoms and metabolic processes in AN and BN have not been examined. Methods Eighty-five women (n = 22 AN binge/purge subtype, n = 33 BN, n = 30 controls) underwent remote salivary cortisol sampling and a 2-day, inpatient study session to examine the effect of stress on cortisol, gut hormones [acyl-ghrelin, peptide tyrosine tyrosine (PYY) and glucagon-like peptide-1] and food consumption. Participants were randomized to either an acute stress induction or control task on each day, and plasma hormones were serially measured before a naturalistic, ad libitum meal. Results Cortisol-awakening response was augmented in AN but not in BN relative to controls, with body mass index explaining the most variance in post-awakening cortisol (36%). Acute stress increased acyl-ghrelin and PYY in AN compared to controls; however, stress did not alter gut hormone profiles in BN. Instead, a group-by-stress interaction showed nominally reduced cortisol reactivity in BN, but not in AN, compared to controls. Ad libitum consumption was lower in both patient groups and unaffected by stress. Conclusions Findings extend previous reports of metabolic dysfunction in binge-eating disorders, identifying unique associations across disorders and under stress. Moreover, we observed disrupted homeostatic signaling in AN following psychological stress, which may explain, in part, the maintenance of dysregulated eating in this serious illness.


1994 ◽  
Vol 87 (5) ◽  
pp. 599-606 ◽  
Author(s):  
J. O. Tirapegui ◽  
Z. A. H. Yahya ◽  
P. C. Bates ◽  
D. Joe Millward

1. The influence of dietary energy restriction and corticosterone on long bone and muscle growth, and their interrelationships, was studied in rats fed a range of restricted amounts of diets containing increasing concentrations of protein, thus maintaining constant protein intakes. Tibial length and epiphyseal cartilage width were measured radiographically. 2. In experiment 1, tibial length and gastrocnemius muscle growth were examined in ad libitum fed rats and during 4 days of severe energy restriction (25% ad libitum intake), starvation and ad libitum feeding with corticosterone treatment (10 mg/100 g), a mediator of the response to energy restriction. Weight loss occurred in all groups. Tibial growth continued in the 25% and starvation groups albeit at reduced rates with the inhibition of starvation > 25% group (P < 0.05), but was arrested after 2 days of corticosterone treatment. 3. Muscle growth inhibition was proportional to tibial growth inhibition of the 25% group, insofar as the muscle/bone ratio (W/L3.85), was maintained. This inter-relationship between muscle and bone growth previously reported for ad libitum high-protein-fed rats, is likely to reflect the anabolic influence of bone on muscle via passive muscle stretching induced by length growth. For both starvation and corticosterone groups the muscle/bone ratio fell (P < 0.05 compared with the ad libitum group), suggesting that muscle growth inhibition included an additional direct catabolic influence of starvation and corticosterone treatment. 4. In experiment 2, measurements of bone, muscle and liver growth were made in rats fed 75%, 50% and 25% ad libitum intakes and fed ad libitum intakes with corticosterone treatment for 8 days. Although body weight growth was arrested in all groups with weight loss in the 50%, 25% and corticosterone groups (P < 0.05), some tibial length growth continued at all levels of energy restriction, with significant reductions in length in the 50% and 25% groups at 4 days and in all groups at 8 days. Corticosterone treatment immediately arrested length growth. The epiphyseal cartilage widths of all restricted groups were significantly reduced at 4 days, graded with the degree of restriction, with corticosterone treatment most marked. 5. Muscle growth continued at near normal rates in the 75% and 50% groups, slowing only after 4 days, but was arrested in the corticosterone and 25% group with weight loss by 4 days in the corticosterone group and after 4 days in the 25% group. Muscle growth appeared relatively resistant to direct inhibition by energy restriction, following tibial growth in all restricted groups in that the muscle/bone ratios were initially maintained in all energy-restricted groups, falling only with the corticosterone treatment or 8 days of 50% and 25% intakes. In contrast, liver lost weight in all restricted groups during the first 4 days. 6. The results show a graded delayed inhibitory influence of energy deficiency on bone growth, which may be mediated by corticosteroids given the marked inhibitory influence of corticosterone. The relative resistance of muscle growth to energy restriction during liver and body-weight loss, is consistent with a powerful physiological anabolic stimulus of muscle stretching by bone length growth that appears to override any dietary-induced catabolic influence.


2019 ◽  
Vol 150 (3) ◽  
pp. 623-633 ◽  
Author(s):  
Kristine Beaulieu ◽  
Nuno Casanova ◽  
Pauline Oustric ◽  
Jake Turicchi ◽  
Catherine Gibbons ◽  
...  

ABSTRACT Background Continuous energy restriction (CER) is purported to be problematic because of reductions in fat-free mass (FFM), compensatory motivation to overeat, and weakened satiety. Intermittent energy restriction (IER) is an alternative behavioral weight loss (WL) strategy that may mitigate some of these limitations. Objective The objective of the DIVA study was to compare the effects of CER and IER on appetite when the degree of WL (≥5%) is matched. Methods Women with overweight/obesity (BMI 25.0–34.9 kg/m2; age 18–55 y) were recruited for this controlled-feeding RCT via CER (25% daily energy restriction) or IER (alternating ad libitum and 75% energy restriction days). Probe days were conducted at baseline and post-intervention to assess body composition, ad libitum energy intake and subjective appetite in response to a fixed-energy breakfast, and eating behavior traits. After baseline measurements, participants were allocated to CER (n = 22) or IER (n = 24). Per protocol analyses (≥5% WL within 12 wk) were conducted with use of repeated measures ANOVA. Results Thirty of 37 completers reached ≥5% WL [CER (n = 18): 6.3 ± 0.8% in 57 ± 16 d, IER (n = 12): 6.6 ± 1.1% in 67 ± 13 d; % WL P = 0.43 and days P = 0.10]. Fat mass [−3.9 (95% CI: −4.3, −3.4) kg] and FFM [−1.3 (95% CI: −1.6, −1.0) kg] were reduced post-WL (P &lt; 0.001), with no group differences. Self-selected meal size decreased post-WL in CER (P = 0.03) but not in IER (P = 0.19). Hunger AUC decreased post-WL (P &lt; 0.05), with no group differences. Satiety quotient remained unchanged and was similar in both groups. Both interventions improved dietary restraint, craving control, susceptibility to hunger, and binge eating (P &lt; 0.001). Conclusions Controlled ≥5% WL via CER or IER did not differentially affect changes in body composition, reductions in hunger, and improvements in eating behavior traits. This suggests that neither CER nor IER lead to compensatory adaptations in appetite in women with overweight/obesity. This trial was registered at clinicaltrials.gov as NCT03447600.


2021 ◽  
Author(s):  
Michelle SSN Faria ◽  
Vinicius E Pimentel ◽  
Júlia l Venturini Helaehil ◽  
Mayara Correa Bertolo ◽  
Nathalia Tonus Horas Santos ◽  
...  

Abstract Background: Caloric restriction (CR) is a type of dietary intervention that is essential in weight loss through modulation of critical pathways of metabolic control; however, it is not yet clear what this intervention results to in association with renovascular hypertension.Methods: Rats were divided into three groups: SHAM, and two groups that underwent surgery to clip the left renal artery and induce renovascular hypertension (OH and OHR). The SHAM diet was as follows: 14 weeks normolipidic diet; OH: 2 weeks normolipidic diet + 12 weeks hyperlipidic diet, both ad libitum; OHR, 2 weeks normolipidic diet + 8 weeks ad libitum high-fat diet + 4 weeks 40% calorie-restricted high-fat diet. Results: Rats in the OHR group had decreased blood pressure, body weight, and glucose levels. Reductions in insulinemia and in lipid and islet fibrotic areas in the OHR group were observed, along with increased insulin sensitivity and normalization of insulin-degrading enzyme levels. The expression of nicotinamide phosphoribosyltransferase (NAMPT), insulin receptor (IR), sirtuin 1 (SIRT1), and complex II proteins were increased in the liver tissue of the OHR group. Strong correlations, whether positive or negative, were evaluated via Spearman’s model between SIRT1, AMPK, NAMPT, PGC-1α, and NNMT expressions with the restoration of normal blood pressure, weight loss, glycemic and lipid panel, and mitochondrial adaptation. Conclusion: CR provided short-term beneficial effects to recover the physiological parameters induced by a high-fat diet and renal artery stenosis in obese and hypertensive animals. These benefits, even in the short term, can provide physiological benefits in the long term.


2003 ◽  
Vol 88 (4) ◽  
pp. 1577-1586 ◽  
Author(s):  
David S. Weigle ◽  
David E. Cummings ◽  
Patricia D. Newby ◽  
Patricia A. Breen ◽  
R. Scott Frayo ◽  
...  

Loss of body fat by caloric restriction is accompanied by decreased circulating leptin levels, increased ghrelin levels, and increased appetite. In contrast, dietary fat restriction often decreases adiposity without increasing appetite. Substitution of dietary carbohydrate for fat has been shown to increase the area under the plasma leptin vs. time curve (AUC) over the course of 24 h. This effect, if sustained, could explain the absence of a compensatory increase in appetite on a low fat diet. To clarify the effect of dietary fat restriction on leptin and ghrelin, we measured AUC for these hormones in human subjects after each of the following sequential diets: 2 wk on a weight-maintaining 35% fat (F), 45% carbohydrate (C), 20% protein (P) diet (n = 18); 2 wk on an isocaloric 15% F, 65% C, 20% P diet (n = 18); and 12 wk on an ad libitum 15% F, 65% C, 20% P diet (n = 16). AUC for leptin was similar on the isocaloric 15% F and 35% F diets (555 ± 57 vs. 580 ± 56 ng/ml·24 h; P = NS). Body weight decreased from 74.6 ± 2.4 to 70.8 ± 2.7 kg on the ad libitum 15% F diet (P &lt; 0.001) without compensatory increases in food consumption or AUC for ghrelin. Proportional amplitude of the 24-h leptin profile was increased after 12 wk on the 15% fat diet. We conclude that weight loss early in the course of dietary fat restriction occurs independently of increased plasma leptin levels, but that a later increase in amplitude of the 24-h leptin signal may contribute to ongoing weight loss. Fat restriction avoids the increase in ghrelin levels caused by dietary energy restriction.


2019 ◽  
Author(s):  
Petras Minderis ◽  
Andrej Fokin ◽  
Mantas Dirmontas ◽  
Aivaras Ratkevicius

AbstractBackgroundReported differences in effects of low and high carbohydrate diets on weight control and metabolic health are controversial. We aimed to examine if such diets induce different improvements in body composition and glucose tolerance under conditions of caloric restriction (CR) in obese mice.MethodsMale C57BL/6J mice (n = 20) were fed obesogenic diet (45 and 17.5% kcal from fat and sugar) ad libitum for 18 weeks and then subjected to 6-week CR which progressively increased up to 40% using either Low Fat diet (20, 60, 20% kcal from fat, carbohydrate, protein, n = 10) or Low Carb diet (20, 60, 20% kcal from carbohydrate, fat, protein, n = 10). Mice fed regular chow diet ad libitum served as controls (n = 10). Body mass, hind limb muscle mass, fat mass, energy expenditure and glucose tolerance were compared between the groups.ResultsLow Fat and Low Carb groups had similar body mass (p > 0.05) prior to CR which was 30% greater compared to control group (p < 0.001). CR resulted in weight loss with no differences between Low Fat and Low Carb groups (30.0 ± 5.6 and 23.8 ± 7.5%, p > 0.05). Weight loss was mainly due to fat loss in both groups. Energy expenditure of freely moving mice did not differ between the groups (p > 0.05). Intraperitoneal glucose tolerance test improved compared to control group (p < 0.05) and values before CR (p < 0.01) but without differences between Low Fat and Low Carb groups (p > 0.05).ConclusionsDietary carbohydrate or fat content when protein is equated does not play a significant role for body composition and metabolic health benefits of caloric restriction in obese mice.


2020 ◽  
Vol 151 (1) ◽  
pp. 245-254
Author(s):  
Sridevi Krishnan ◽  
Sean H Adams ◽  
Megan G Witbracht ◽  
Leslie R Woodhouse ◽  
Brian D Piccolo ◽  
...  

ABSTRACT Background Inclusion of dairy in diet patterns has been shown to have mixed effects on weight loss. A prevailing hypothesis is that dairy improves weight loss by influencing endocrine systems associated with satiety and food intake regulation. Objectives The objective of the current study was to evaluate the effect of weight loss with or without adequate dietary dairy on subjective and objective appetitive measures. Methods Men and women who were habitual low dairy consumers (n = 65, 20–50 y) participated in a 12-wk randomized controlled feeding weight loss trial. During the 12-wk intervention, a low-dairy (&lt;1 serving dairy/d) was compared with an adequate-dairy (3–4 servings dairy/d) diet, both with a 500-kcal deficit/d. Test days, before and at the end of the intervention, began with 2 fasting blood draws and visual analog scale (VAS) measures, followed by a standard breakfast (25% of prescribed restricted calories), 5 postbreakfast blood draws and VASs, a standard lunch (40% of restricted energy amount), and 12 postlunch blood draws and VASs. Blood samples were used for satiety hormone measurements. On a separate day when matching standard meals were consumed, an ad libitum buffet meal was provided as dinner, at a self-selected time. Meal duration and intermeal interval were recorded. Results Weight loss (−6.1 kg), irrespective of dairy, resulted in reduced fasting insulin (−20%) and leptin (−25%), and increased fasting acylated ghrelin (+25%) and VAS desire to eat (+18%) (P &lt; 0.05). There were no effects of dairy on objective or subjective satiety measures. Weight loss marginally reduced the intermeal interval (289 min compared with 276 min, P = 0.059) between lunch and the ad libitum buffet. Conclusions These results do not support the hypothesis that inclusion of dairy in long-term dietary patterns influences appetite during weight loss. Weight loss per se has a modest impact on select systems that regulate hunger and satiety. This trial was registered at clinicaltrials.gov as NCT00858312.


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