Determination of the Optimum Dietary Proportions of Lysine and Tryptophan for Growing Rats Based on Growth, Food Intake and Plasma Metabolites

AbstractTo study, in young growing rats, the consequences of different levels of dietary protein deficiency on food intake, body weight, body composition, and energy balance and to assess the role of FGF21 in the adaptation to a low protein diet. Thirty-six weanling rats were fed diets containing 3%, 5%, 8%, 12%, 15% and 20% protein for three weeks. Body weight, food intake, energy expenditure and metabolic parameters were followed throughout this period. The very low-protein diets (3% and 5%) induced a large decrease in body weight gain and an increase in energy intake relative to body mass. No gain in fat mass was observed because energy expenditure increased in proportion to energy intake. As expected, Fgf21 expression in the liver and plasma FGF21 increased with low-protein diets, but Fgf21 expression in the hypothalamus decreased. Under low protein diets (3% and 5%), the increase in liver Fgf21 and the decrease of Fgf21 in the hypothalamus induced an increase in energy expenditure and the decrease in the satiety signal responsible for hyperphagia. Our results highlight that when dietary protein decreases below 8%, the liver detects the low protein diet and responds by activating synthesis and secretion of FGF21 in order to activate an endocrine signal that induces metabolic adaptation. The hypothalamus, in comparison, responds to protein deficiency when dietary protein decreases below 5%.

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A comparison of the effects of infection with Eimeria maxima and dietary restriction on weight gain, plasma metabolites and liver glycogen in the immature fowl, Gallus domesticus

Parasitology ◽

10.1017/s0031182000044772 ◽

1982 ◽

Vol 84 (2) ◽

pp. 205-213 ◽

Cited By ~ 11

Author(s):

H. D. Chapman ◽

D. L. Fernandes ◽

T. F. Davison

Keyword(s):

Growth Rate ◽

Body Weight ◽

Uric Acid ◽

Weight Gain ◽

Food Intake ◽

Acute Phase ◽

Plasma Glucose ◽

Liver Glycogen ◽

Plasma Metabolites ◽

Eimeria Maxima

SUMMARYThe effects of Eimeria maxima or restricted pair-feeding on weight gain, plasma concentrations of protein, glucose, free fatty acids (FFA) and uric acid and liver glycogen were compared in immature fowl. Food intake/kg body weight and weight gain decreased during the acute phase of infection (days 5–7) while weight loss was prolonged for an extra day compared with pair-fed birds. During recovery, food intake/kg body weight of infected birds was greater than that of non-infected controls but there was no evidence for an increase in growth rate compared with controls when body weight was considered. Growth rate of pair-fed birds was greater than that of infected birds during recovery, indicating their better use of ingested food. Liver glycogen and plasma protein concentration were decreased during the acute phase of infection but the concentrations of plasma glucose, free fatty acid (FFA) and uric acid were not affected. In pair-fed birds liver glycogen was depleted, concentrations of plasma glucose and uric acid decreased and FFA increased, and these changes persisted for the remainder of the experiment. The findings are similar to those in birds whose food has been withheld and were probably due to the pattern of food intake imposed by the experimental protocol. It is concluded that the metabolic differences between infected and pair-fed birds are of doubtful significance.

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Determination of Digestibility, Tissue Deposition, and Metabolism of the Omega-3 Fatty Acid Content of Krill Protein Concentrate in Growing Rats

Journal of Agricultural and Food Chemistry ◽

10.1021/jf9036408 ◽

2010 ◽

Vol 58 (5) ◽

pp. 2830-2837 ◽

Cited By ~ 18

Author(s):

Kayla M. Bridges ◽

Joseph C. Gigliotti ◽

Stephanie Altman ◽

Jacek Jaczynski ◽

Janet C. Tou

Keyword(s):

Fatty Acid ◽

Acid Content ◽

Fatty Acid Content ◽

Protein Concentrate ◽

Omega 3 ◽

Omega 3 Fatty Acid ◽

Growing Rats

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Effects of chronic long-acting bromocriptine treatment on liveweight, voluntary food intake, coat growth and breeding season in non-pregnant red deer hinds

Journal of Endocrinology ◽

10.1677/joe.0.1190413 ◽

1988 ◽

Vol 119 (3) ◽

pp. 413-420 ◽

Cited By ~ 46

Author(s):

J. D. Curlewis ◽

A. S. I. Loudon ◽

J. A. Milne ◽

A. S. McNeilly

Keyword(s):

Food Intake ◽

Breeding Season ◽

Red Deer ◽

Vehicle Group ◽

High Dose ◽

Group A ◽

Long Acting ◽

Group B ◽

Voluntary Food Intake

ABSTRACT Seventeen red deer hinds were housed in individual pens and from 28 February until 11 November were injected each week with vehicle (group A; n = 6) or 5 (group B; n = 6) or 12·5 mg (group C; n = 5) of a long-acting formulation of bromocriptine. Liveweight and voluntary food intake (VFI) were recorded for each hind, and blood was collected for determination of progesterone, prolactin, tri-iodothyronine (T3) and cortisol concentrations by radioimmunoassay. Treatment with the high dose of bromocriptine was associated with a significant (P <0·05) reduction in VFI, with the effect being greatest between March and July. There was no treatment effect on liveweight, but there was a significant (P <0·01) interaction between time and treatment due to the faster rate of weight gain in control animals at the beginning of the experiment. Changes in liveweight could be explained by changes in VFI rather than by changes in the efficiency of utilization of intake. Termination of the breeding season was significantly (P <0·01) delayed by 54 days in group C hinds. Growth of the summer coat and subsequent winter coats was delayed by 1 and 3 months respectively in group C hinds, and in groups B and C the duration that animals were in summer coat was increased by about 1 month. The seasonal increase in prolactin concentrations was seen in all groups, but levels were significantly (P <0·05) lower in group C hinds. Concentrations of T3 and cortisol were not affected by bromocriptine. J. Endocr. (1988) 119, 413–420

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Abstract MP17: Time Restricted Feeding Improves Cardiovascular Rhythms And Vascular Metabolism In Mice On A Chronic High Fat Diet

Hypertension ◽

10.1161/hyp.76.suppl_1.mp17 ◽

2020 ◽

Vol 76 (Suppl_1) ◽

Author(s):

Paramita Pati ◽

Dingguo Zhang ◽

Jackson Colson ◽

Shannon M Bailey ◽

Karen L Gamble ◽

...

Keyword(s):

Locomotor Activity ◽

Food Intake ◽

High Fat Diet ◽

Disease Risk ◽

Plasma Metabolites ◽

Diurnal Changes ◽

Restricted Feeding ◽

High Fat ◽

Inactive Period ◽

Cardiovascular Rhythms

Irregular timing of food intake increases hypertension and cardiometabolic disease risk. A chronic high fat diet (HFD) also disrupts circadian rhythms. We hypothesized that active period time restricted feeding (TRF) during the last 2 weeks in mice on a chronic HFD will improve blood pressure rhythm, diurnal variation of circulating plasma factors, and vascular metabolism. Mice (male 8-week old, C57BL/6J) were fed a normal diet (ND; 10% fat) or HFD (45% fat) for 20 weeks ad libitum. For the final 2 weeks, half of the HFD mice were subjected to TRF. Mean arterial pressure (MAP), heart rate (HR), and locomotor activity were assessed by telemetry. TRF significantly increased the active-inactive period difference in MAP and HR in in mice fed a HFD (ΔMAP: ND: 16±0.7 mmHg, HFD: 15±0.8 mmHg, HFD+TRF: 18±0.9 mmHg, n=6-8, p=0.01; ΔHR: ND: 68±5.1 bpm, HFD: 69±6.5 bpm, HFD+TRF: 113±7.9 bpm, n=6-8, p<0.01). Diurnal changes in locomotor activity are not different between groups. At the end of the study, plasma was collected at 4 hour intervals over a 24 hour period (ZT0 at 7AM; ZT12 at 7PM). Circulating levels of liver-derived mediators β-hydroxybutyrate (βHB) and insulin-like growth factor-1 (IGF-1) showed significant differences due to diet but not TRF (βHB, ZT21: ND: 0.16±0.01 mM, HFD: 0.20±0.02 mM, HFD+TRF: 0.19±0.01 mM, n=5-6, p=0.02; IGF-1, ZT5: ND: 232±18 ng/mL, HFD: 292±34 ng/mL , HFD+TRF: 371±14 ng/mL, n=5-6, p<0.01). Plasma leptin was significantly higher in mice on HFD and reduced by TRF at ZT12 (ND: 5.3±1.3 ng/mL, HFD: 22.5±2.9 ng/mL, HFD+TRF: 10.3±3.5ng/mL, n=5-6, p<0.01) and ZT17 (ND: 6.7±1.1 ng/mL, HFD: 32.5±3.0 ng/mL, HFD+TRF: 25.0±1.3 ng/mL, n=5-6, p<0.01). Plasma adiponectin was unchanged between all groups. TRF in HFD mice increased NAD + , important for metabolism, in renal vessels at ZT17 (HFD: 0.10±0.02 pmol/μg; HFD+TRF: 0.19±0.03 pmol/μg; n=5, p=0.03). Aortic NAD + at ZT1 was not affected by TRF in HFD mice (HFD: 1.83±0.35 pmol/μg, HFD+TRF: 1.35±0.35 pmol/μg, n=4, p=0.37). Our results indicate that TRF in mice on HFD increases the active-inactive period difference in MAP and HR and alters plasma metabolites, suggesting the timing of food intake on a chronic HFD improves cardiovascular rhythms with increased renal vascular metabolism and reduced leptin levels.

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65Zn-Labeled Tissue Zinc for Determination of Endogenous Fecal Zinc Excretion in Growing Rats

Annals of Nutrition and Metabolism ◽

10.1159/000175716 ◽

1976 ◽

Vol 20 (5) ◽

pp. 314-320 ◽

Cited By ~ 27

Author(s):

E. Weigand ◽

M. Kirchgessner

Keyword(s):

Growing Rats

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Cultural aspects of meals and meal frequency

British Journal Of Nutrition ◽

10.1079/bjn19970101 ◽

1997 ◽

Vol 77 (S1) ◽

pp. S21-S28 ◽

Cited By ~ 41

Author(s):

Matty Chiva

Keyword(s):

Food Intake ◽

Cultural Models ◽

Cultural Economic ◽

Cultural Elements ◽

Cultural Aspects ◽

Subjective Perceptions ◽

Value Judgements ◽

Future Data ◽

The Subject

AbstractsThe present paper presents a certain number of cultural elements which interact in the determination of the frequency of food intake. Approaches from various perspectives (historical, ethnological, anthropological, sociological) draw attention to two major aspects relating to the periodicity of food intake: the extreme cultural diversity and the continual modifications which have occurred over time and space. The various cultural models change and are subject to multiple influences, for example, cross-cultural, economic and historical. In addition, there are interactions between the models. The definitions of food intake and frequency play a major role in building up consumers' perceptions. These various perceptions are multiple (perception of self, of food and its virtues, the rules and moral values of consumption) and finally influence behaviours. Finally, and taking into account the systems of beliefs, the very nature of feeding behaviours may carry feelings of guilt for the subject. The study of real behaviours and their relationship with health is still incomplete for reasons of methodology and also of conceptual definition. In future, data collection has to take into account real behaviour as well as subjective perceptions and value judgements. A specific effort has to be made in the future to develop methodology. This should allow the collection of reliable data and particularly comparisons between studies, without oversimplifying and distorting cultural specificities.

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