While caloric restriction is a proven means to extend longevity, its effects on bone are not well understood. This study examined the effects of dietary restriction without vitamin or mineral supplementation on bone in female 60- and 120-day-old C57BL/6J mice. Baseline controls were sacrificed at 60 or 120 days, while ...

The inhibitory activity against mammary carcinogenesis mediated by energy restriction is accompanied by a reduction in the degree of mammary ductal branching, and an increase in adrenal cortical activity. Levels of p27/kip1 protein, a gene product associated with cell cycle growth arrest, have also been shown to be elevated in ...

The purpose of this study was to determine whether aging alters neuronal uptake of norepinephrine (NE) in the rat heart and if dietary restriction influenced the effect of age on this system. Cardiac synaptosomes were prepared from 6-, 12- and 24-month-old male F344 rats fed ad libitum (AL) or a ...

The effect of long-term food restriction on the sensitivity of the pituitary to exogenously administered chicken luteinizing hormone releasing hormone I (cLHRH-I) was investigated in three groups of broiler breeder females fed ad libitum, fed a restricted quantity of food or fed a restricted quantity of food to obtain an ...

In a series of four experiments, the effects of differences in dietary protein intake on BW, skeletal growth and the weight of the Pectoralis major muscle was studied in Hubbard Standard and Hubbard Hi-Y broiler breeder pullets. In Experiment 1, pullets were fed diets with either 15, 17, or 19% ...

BACKGROUND: Undernutrition during early life may have both immediate and later consequences. This study was undertaken to measure the long-term effects of perinatal undernutrition on the growth and function of the gastrointestinal tract. METHODS: Pregnant rats were assigned to one of four groups that received isocaloric diets restricted in protein ...

This study examined the effect of feeding either a bland cornstarch-based diet (BCD) or a highly palatable, high fat diet containing sucrose (HPD) on hypothalamic arcuate nucleus (ARC) gene expression for neuropeptide-Y (NPY). Male Sprague-Dawley rats received either BCD ad libitum, HPD ad libitum, HPD pair-fed to the caloric intake ...

In female mice on a control diet (3.6% fat) reduced physical activity leads to a reduction of the average life span. So the average age at death of an inactive group is 500 +/- 166 compared to 565 +/- 175 days in an active control group. If the animals are ...

The mouse skin tumor initiation-promotion model was used to investigate the protective effect of diet restriction in mechanistic and quantitative terms. A total of five groups of 14 male NMRI mice were initiated with 100 nmol 7,12-dimethylbenz[a]anthracene (DMBA) and promoted twice weekly with 2.5, 1.25, or 0.625 nmol 12-O-tetradecanoylphorbol-13-acetate (TPA). ...

C57B1/6 mice aged 3, 10, and 26 months were tested for spatial learning in the Morris water maze. Ten and 26 month old mice were ad libitum-fed or diet restricted (60% of ad libitum-fed calories). Diet restriction significantly improved memory performance among the 10 and 26 month olds. In age/diet ...

Subjects taking a hydrogen pump blocking agent (omeprazole) develop bacterial overgrowth of the small intestine. We tested the hypothesis that this bacterial overgrowth produces menaquinones, which would meet the vitamin requirement in situations of vitamin K deficiency. In a crossover-type design, 13 healthy volunteers eating a phylloquinone-restricted diet for 35 ...

In immature female rats (21 days), a restricted diet (50% of the daily normal intake for 25 days) interrupts sexual development, leaving animals in a state of sexual immaturity. Food restriction does not affect the use of glycogen in uteri isolated and increases 14CO2 production from U14C-glucose in relation to ...

Calorie restriction can induce phase-advances of daily rhythms in rodents exposed to light-dark cycles. To test whether glucose-responsive neurons are involved in the synchronizing effects of calorie restriction, C57BL/6J mice were injected with gold-thioglucose (GTG; 0.6 g/kg) which damages glucose-responsive neurons, primarily located in the ventromedial hypothalamus. From the day ...

The daily caloric intake and circadian pattern of macronutrient self-selection were examined in rats subjected to 3 h of food and water deprivation at the beginning or at the end of darkness. When one sole 3-h period of deprivation was applied, rats showed a compensatory response characterized by an unscheduled ...

The prevalence of musculoskeletal disease at eight, 16, 24, 34, 44 and 54 weeks of age in male and female turkeys was determined by dissecting 688 limbs from traditional lines and sire-line turkeys fed to achieve different bodyweights. Traditional turkeys were fed ad libitum and sire-line turkeys were fed ad ...

Very low protein diets result in a desensitization of hepatic cAMP signaling in rats, which is characterized by a loss of cAMP-dependent protein kinase (PKA) activity and type I regulatory subunit (RI). Here we have tested whether more moderate protein restriction (Trial 1) or energy restriction (Trial 2) also modulates ...

Growth data of some bones (shank, tibia, and keel) and the digestive tract in White Leghorn pullets, which consumed ad libitum and restricted diets, were analyzed by mono- and diphasic allometric functions. Fat-free plucked empty body mass (FFEBM) or a functional entity was used as the independent variable in the ...

Effect of mineral restriction was studied to clarify which mineral in the diet is most indispensable in preventing paraquat (PQ) toxicosis. ODS rats were chosen as the experimental animal owing to the inability to synthesize vitamin C similarly to humans. Rats were fed with either mineral-adequate or restricted diets dosed ...

BACKGROUND: Nutritional dwarfing, a form of suboptimal nutrition, has been identified as a frequent cause of short stature and delayed sexual development in children. Retarded growth is an adaptive response to suboptimal nutrition. OBJECTIVE: To assess whether recombinant human growth hormone (rhGH) may promote growth during various levels of suboptimal ...

Male turkeys of two commercial Large White strains (Nicholas 88, BUT 6) were subjected to growth restriction by means of reducing amino acid (AA) content of diets to a minimum of 75% of NRC (1994) suggested levels. There were three periods when diets containing 75% of NRC recommended AA for ...

OBJECTIVE: Dietary fat restriction is currently being promoted as a weight loss strategy. However, previous investigations suggest that fat restriction alone may not be more beneficial than total energy restriction for the treatment of obesity. The purpose of this project was to assess whether an energy-restricted or fat-restricted diet was ...

The effect of a food-restricted diet on the fecal microflora of rats was studied by determining total anaerobic bacteria, bacterial cellular fatty acids, and the predominant intestinal bacteria shown by polymerase chain reaction (PCR) primers specific for the 16S rRNA gene sequences of 12 bacterial species. Twenty-four female Fischer 344 ...

Exposure to oxidants or phosphate, especially in the presence of calcium, has been long known to lead to mitochondrial structural alteration and damage. In the past 15 years, it has become increasingly appreciated that this damage is often the result of a cyclosporin A-sensitive event, the "permeability transition" (PT). Using ...

BACKGROUND: A cohort study was performed of 8 people sealed inside Biosphere 2 to evaluate the effects of dietary restriction in humans on lipid and lipoprotein levels and the relationship of these levels to energy, fat, and protein content of the diet, and body weight, weight change, and energy expenditure. ...

The conditions under which laboratory animals are maintained can powerfully influence the results of toxicological studies utilized for risk assessment. Nutrition is of importance in toxicological bioassays and research, because diet composition and the conditions under which it is fed can affect the metabolism and activity of xenobiotic test substances ...

We administered clenbuterol as a dietary admixture (4 mg/kg diet) to three groups of male Wistar rats (n = 8) housed individually in metabolism cages and fed for 15 d at 110, 160, and 235% (ad libitum) of the estimated requirement for energy maintenance. Untreated groups at each level of ...

Cytosolic and mitochondrial levels of glutathione (GSH) as well as the activities of glyoxalase I (GI) and glyoxalase II (GII), GSH-dependent enzymes involved in the detoxification of 2-ketoaldehydes, were investigated in the liver of ad libitum (AL) fed and food restricted (FR) rat during aging. Both cytosolic and mitochondrial GSH ...

Management of obesity should initially involve assessment of the pet to rule out other possible medical problems and provide an accurate dietary history. It is essential to obtain a good estimate of the existing caloric intake, including calories from table scraps, pet treats, or other sources. Assessing the owner's willingness ...

Controversy regarding the use of ad libitum feeding in chronic rodent toxicity studies will soon result in issue of a FDA Points to Consider document. Caloric intakes are now recognized to be important uncontrolled variables in bioassays because rodents chronically fed ad libitum become obese, reproductively senile and have increased ...

To study the effects of maternal nutritional status on lactational performance, the diets of laboratory rats were manipulated with food restriction or increases in fat concentration. Compared with rats fed control diets ad libitum, conception rate, milk production and litter growth decreased and milk fat concentration increased in both chronically ...

Habitat-induced alterations of immune system function have been implicated in the regulation of survival rates in wild herbivore populations. Protein availability in the diet has been shown to fluctuate with density and influence immunity in hispid cotton rats (Sigmodon hispidus), a common herbivorous rodent of the southeastern United States. In ...

It has been observed that susceptibility to many degenerative diseases increases concurrently with industrialization and rising living standards. Although epidemiologic studies suggest that specific environmental and dietary factors may be important, caloric intake alone (as reflected in body size) may account for much of the differential risk observed among diverse ...

To investigate interactive effects of dietary fatty acid composition and energy restriction on body lipid metabolism and its regulation, rats were fed for 10 weeks diets varying in fat type and energy intake level. Energy deficiency was achieved by removing carbohydrate from the diets while keeping fat and other nutrient ...

At 6 weeks of age, male Fischer F344 rats were fed a purified, casein based diet either ad libitum or in the amount of 60% of the diet consumed by the rats, fed ad libitum (restricted diet). Femur bone tissues were obtained from the rats at 4 and 13 months ...

The interosseal and suspensory ligaments of the axial and appendicular skeleton of the Western Mosquitofish, Gambusia affinis affinis were investigated in whole-mounted late embryonic and adult female and male G. a. affinis stained with alcian blue and alizarin red S, cleared, and viewed using differential interference contrast. The interosseal and ...

A study was designed to evaluate quantitative ultrasonographic characteristics of a diffuse parenchymal disease in an experimental model of subclinical fatty infiltration of the liver using diet-induced obesity and dietary restriction in the cat. Ultrasound images of livers were quantitatively analysed by a video signal analysis technique before, during and ...

Dietary calorie restriction extends both mean and maximum life span and retards age-related diseases, including eye lens cataract in Emory mice. The beneficial effects of calorie restriction have been hypothesized to reflect enhanced tissue antioxidant capacity. As a test of this hypothesis, we reared male and female Emory mice on ...

A trial was designed to determine the effect of season and feed restriction on LH and prolactin secretion, adrenal response, insulin and FFA in the early pregnant gilt. Groups of cross bred gilts (n = 24) were mated and allocated to two feeding levels; a non-restricted group received close to ...

Charles Foster littermate albino rats (72) were randomized into 9 independent groups in a 3 x 3 factorial design by varying nutrition and environment each at three levels: normal nutrition, 25% nutritional restriction and 50% nutritional restriction; normal environment, 3-week environmental restriction and 6-week environmental restriction. The nutritional and environmental ...

Studies were undertaken to determine whether dietary restriction protects against acute pulmonary oxidant challenge. Male F344 rats were fed NIH-31 diet either ad libitum or at restricted levels equal to 75% that of ad libitum intake. After 3 wk of dietary adaptation, animals were exposed by inhalation to 2.0 ppm ...

The effects of dietary restriction on serum antioxidant capacities were studied in male Fischer 344 rats. Dietary restriction was started at the age of 6 weeks and consisted of 60% of the mean daily food intake of the ad libitum fed controls. They were killed at 7 and 18 months ...

It has been demonstrated repeatedly that caloric restriction, or underfeeding, will inhibit the growth of spontaneous, transplanted, or induced tumors in mice and rats. Caloric restriction will inhibit tumorigenesis even in the face of a high fat diet. The mechanism of action is moot but caloric restriction reduces plasma insulin ...

Studies were conducted to compare outcomes when four chemicals were evaluated under typical NTP bioassay conditions as well as under protocols employing dietary restriction. Specific experiments were designed to evaluate the effect of diet restriction on the sensitivity of the bioassay toward chemical-induced chronic toxicity and carcinogenicity and to evaluate ...

Retinoids were analyzed in 11-day chick embryos and eggs from white Leghorn hens (Gallus domesticus) fed environmentally-derived polychlorinated biphenyls (PCB) in carp (Cyprinus carpio) from Saginaw Bay. The yolks and the embryos contained all-trans-retinol, 3,4-didehydroretinol and retinyl esters. There was no significant difference in the total retinoid content in the ...

Chromium is an essential nutrient required for sugar and fat metabolism. Normal dietary intake of Cr for humans is suboptimal. The estimated safe and adequate daily dietary intake for Cr is 50 to 200 microg. However, most diets contain less than 60% of the minimum suggested intake of 50 microg. ...

Dietary restriction (DR) markedly extends mean and maximal life span, and retards the rate of biological aging in rodent models; however, it is unknown if these results occur in primate species. The purpose of the current study was to investigate selected immunologic outcomes in Rhesus monkeys subjected to DR for ...

Growth patterns of crude fat (cfat; ether extract), CP, ash, and water in White Leghorn pullets that ate ad libitum and restricted (feed or lysine) diets were analyzed by mono- and diphasic allometric functions, with plucked empty body mass (EBM) or fat-free EBM (FFEBM) as the independent variates. In general, ...

The effect of timing of gentamicin dosing relative to food access periods was evaluated in experimental animals. Female Sprague-Dawley rats were treated for 4 and 10 days with gentamicin (40 mg/kg of body weight/day) intraperitoneally at either 0700, 1300, 1900, or 0100 h according to three food presentation schedules: food ...

OBJECTIVE: To evaluate the safety of chromium (Cr) as a nutrient supplement. Several recent studies have reported beneficial effects of supplemental Cr at levels higher than the upper limit of the suggested intake for Cr. Trivalent Cr is considered relatively nontoxic but some recent unconfirmed studies have questioned its toxicity. ...

The present study was designed to determine whether the memory sparing effects of dietary restriction during aging could be through an effect on ionotropic glutamate receptors. Quantitative autoradiography was performed on 3, 10, and 26 month old mice to examine the density changes of NMDA, AMPA and kainate binding sites ...