Food-restricted Group Research Articles

Food restriction during pregnancy and female offspring fertility: adverse effects of reprogrammed reproductive lifespan

BackgroundFood restriction during pregnancy can influence the health of the offspring during the adulthood. The aim of the present study was to examine the effect of maternal food restriction (MFR) on the reproductive performance in female rat offspring from the first (FR1) and second (FR2) generations.MethodsAdult virgin Wistar female rats were given free access to tap water and were fed ad libitum on standard rodent chow, were mated with virgin adult males, and then were randomly divided into two groups: controls (that was fed ad libitum) and food-restricted group (FR, that was given only 50% of ad libitum food throughout gestation). Their first (FR1) and the second (FR2) generation of offspring were fed ad libitum and sacrificed before puberty and at adulthood. Their ovaries were removed and their histology evaluated by estimating the number of follicles (total and at various stages of folliculogenesis), and the presence of multi-nuclei oocytes and multi-oocyte follicles.ResultsTotal number of ovarian follicles was lower in FR1 females at week 4 in comparison with controls, while it was not different in FR2 females vs. controls. The number of the primordial follicle was lower in FR1 and FR2 females vs. controls at both week 4 and at week 8. When compared to the controls, the follicles containing multi-nuclei oocytes were more frequent in ovaries from FR1 and FR2 females at week 4, and higher and lower respectively in ovaries form FR1 and FR2 females at week 8.ConclusionMFR affects ovarian histology by inducing the development of abnormal follicles in the ovaries in first and second generation offspring. This finding could influence the ovarian function resulting in an early pubertal onset and an early decline in reproductive lifespan.

Effects of food limitation on the intensity of blue‐green and brown eggshell coloration: an experimental study with the canary

Variation in blue‐green and brown coloration of avian eggshells could be affected by several factors, including environmental nutritional constraints. Better availability of nutrients could influence the synthesis and deposition of pigments into the eggshell, so we may expect a link between the food availability during egg formation, the body condition of the female and intensity of eggshell coloration. This hypothesis has received mixed support so far: in some bird species a positive correlation between female body condition and eggshell blue‐green coloration could be demonstrated, but other studies failed to find a significant link. In this study, we experimentally limited the food availability for domestic canaries Serinus canaria prior to and during egg laying, and examined its effects on the biliverdin‐ and protoporphyrin‐based eggshell coloration. Treatment had no significant effect on eggshell blue‐green chroma and biliverdin concentration. However, we found a significant positive relationship between female body condition and eggshell background blue‐green chroma in the control group, but not in the food restricted group. Females possibly experiencing a decline in antioxidant capacity due to food limitation may not be able to produce a blue‐green eggshell colour intensity reliably indicating their body condition. Furthermore, food‐restricted canary females laid eggs with significantly higher eggshell brown chroma, spot intensity, and protoporphyrin concentration. Therefore, our results suggest that limitation in actual nutrient availability increases deposition of protoporphyrin into the eggshell, and it may also modify the association between female body condition and intensity of blue‐green eggshell coloration.

Neuroprotective effects of food restriction on autonomic innervation of the lacrimal gland in the rat

Inflammatory mechanisms and oxidative stress play important roles in age-related lacrimal gland (LG) degeneration as well as neural degeneration. Research suggests that caloric restriction can prevent age-related LG dysfunction and increase the life span of neurons. In the present study, we hypothesized that caloric restriction prevents age-related LG dysfunction by ameliorating the influence of inflammatory/oxidative stress on autonomic neurons controlling lacrimal function. We evaluated the effects of food restriction (FR) on inflammatory/oxidative status and on autonomic neural/neuroglial cell populations in LGs from aging rats. A total of 45 female albino rats were divided into young adult, aged, and aged-FR groups. The FR group was subjected to a 50% reduction in food from 14 to 20 months of age. LG samples were collected for each group and subjected to biochemical, histological, and immunohistochemical studies. LGs from aged-FR rats, rather than those from aged rats, showed preservation of their cellular structures, organelles, and Schwan cell units. LG preservation was associated with a marked decrease in inflammatory markers, an increase in cellular antioxidants, and the up-regulation of choline acetyltransverase, tyrosine hydroxylase, neuron-specific enolase and S100. These findings strongly suggest that in aged rats, both oxidative and inflammatory stressors directly contribute to LG dysfunction by mediating the degeneration of autonomic neurons, and that FR can protect against these effects.

Emodin, a compound with putative antidiabetic potential, deteriorates glucose tolerance in rodents

Emodin is found in remedies from Traditional Chinese Medicine. Since antihyperglycaemic action was observed in rodents, non-scientific sources advertise emodin intake as a natural cure for diabetes. Emodin was admixed to high fat-food of obese mice at two doses (2 and 5g/kg; daily emodin uptake 103 and 229mg/kg). Comparison was made to ad libitum fed and to food restricted control groups, the latter showing the same weight gain as the corresponding emodin-treated groups. Emodin blunted food intake by 6% and 20% for the low and high dose, which was accompanied by proportionate reductions in weight gain. Emodin reduced blood glucose relative to freely feeding controls, but comparison to weight-matched controls unmasked deterioration, rather than improvement, of basal glycaemia (mmol/l: fed ad libitum, 9.5±0.4; low emodin, 9.4±0.3, weight-matched, 8.2±0.3; high emodin, 7.2±0.4, weight-matched, 6.1±0.3; P<0.01, emodin vs weight-matched) and glucose tolerance (area under the curve, min*mol/l: fed ad libitum, 2.01±0.08; low emodin, 1.97±0.12, weight-matched, 1.75±0.03; high emodin, 1.89±0.07, weight-matched, 1.65±0.05; P<0.0002, emodin vs weight-matched). An insulin tolerance test suggested insulin desensitisation by prolonged emodin treatment. Furthermore, a single oral emodin dose did not affect glucose tolerance in obese mice, whereas intravenous injection in rats suggested a potential of emodin to acutely impair insulin release. Our results show that the antihyperglycaemic action of emodin as well as associated biochemical alterations could be the mere consequences of a spoilt appetite. Published claims of antidiabetic potential via other mechanisms evoke the danger of misuse of natural remedies by diabetic patients.

Effect of temperature and food restriction on immune function in striped hamsters (Cricetulus barabensis).

Small mammals in temperate areas face seasonal fluctuations of temperature and food availability, both of which may influence their immune responses, which are critical to survival. In the present study, we tested the hypothesis that low temperature and food restriction suppress immune function in striped hamsters (Cricetulus barabensis). Thirty-seven adult male hamsters were randomly assigned to warm (23±1°C) and cold (5±1°C) treatment groups, which were further divided into fed and food-restricted groups. Body mass was not affected by cold stress, food restriction or the interaction cold stress×food restriction. Cold stress decreased total body fat mass, haematological parameters including white blood cells, lymphocytes and neutrophilic granulocytes, and immunoglobin (Ig) M titres 5 days after injecting keyhole limpet haemocyanin (KLH). However, cold temperature increased bacterial killing capacity, indicative of innate immunity, and did not affect the mass of the thymus and spleen, intermediate granulocytes, the phytohaemagglutinin (PHA) response and the levels of blood glucose and serum leptin. Corticosterone concentration was affected significantly by the interaction cold stress×food restriction but not by cold stress or food restriction alone. Food restriction reduced thymus mass, but other immunological parameters including body fat mass, spleen mass, haematological parameters, innate immunity, PHA response, the titres of IgM and IgG, and the levels of blood glucose and serum leptin were all not affected by food restriction or the interaction cold stress×food restriction. Innate immunity was positively correlated with leptin levels, whereas no significant correlations were observed in the levels of blood glucose, serum leptin, corticosterone and all the detected immune parameters. Our results show that cold stress suppressed humoral immunity but enhanced innate immunity and did not affect cellular immunity in striped hamsters. Most immunological indices were not influenced by food restriction. Blood glucose, leptin and corticosterone could not explain the changes of innate, cellular and humoral immunity upon cold stress or food restriction in striped hamsters.

Effects of Feed Restriction on Lipid Dynamics and Reproduction in Northern Bobwhites

High annual and prenesting mortality rates (0.46-0.95) in northern bobwhites (Colinus virginianus) compel these birds to devote extraordinary effort and resources to reproduction. Bobwhites exhibit reproductive behavior characteristic of rapid multi-clutch and ambisexual polygamous mating systems. To better understand the physiological basis of the bobwhite's high reproductive capacity, we studied effects of restricted food intake on lean mass, lipids, and egg laying. We fed 48 bobwhites 3 levels of food intake including ad libitum (100%), and 60% and 80% of ad libitum. After 15 weeks of this protocol, we switched treatments for 50% of the birds in each treatment. Lipid levels were similar for 60% and 80% groups, but significantly greater for the 100% group. Egg laying was markedly depressed and delayed in food-restricted groups. Comparing quail in the 60% and 80% groups, the latter appeared to catabolize body lipids in order to lay eggs. Egg production rates (eggs bird- 1 day- 1) were 0.7 for 100% quail, 0.18 for 80% quail, and 0.03 for 60% quail. After switching treatments, subgroups allotted ad libitum food quickly recovered. The 60% and 80% subgroups reached constant egg production (0.6-0.7 eggs bird- 1 day- 1), and with lean mass and lipid levels (9.8%-13.9% of wet body mass) within 10 days of ad libitum feeding. We discuss partitioning of endogenous reserves for reproduction and importance of exogenous energy in quail ecology.

Protein restriction does not affect body temperature pattern in female mice.

Daily torpor is a physiological adaptation in mammals and birds characterized by a controlled reduction of metabolic rate and body temperature during the resting phase of circadian rhythms. In laboratory mice, daily torpor is induced by dietary caloric restriction. However, it is not known which nutrients are related to daily torpor expression. To determine whether dietary protein is a key factor in inducing daily torpor in mice, we fed mice a protein-restricted (PR) diet that included only one-quarter of the amount of protein but the same caloric level as a control (C) diet. We assigned six non-pregnant female ICR mice to each group and recorded their body weights and core body temperatures for 4 weeks. Body weights in the C group increased, but those in the PR group remained steady or decreased. Mice in both groups did not show daily torpor, but most mice in a food-restricted group (n=6) supplied with 80% of the calories given to the C group exhibited decreased body weights and frequently displayed daily torpor. This suggests that protein restriction is not a trigger of daily torpor; torpid animals can conserve their internal energy, but torpor may not play a significant role in conserving internal protein. Thus, opportunistic daily torpor in mice may function in energy conservation rather than protein saving.

Changes of blood pressure, abdominal visceral fat tissue and gene expressions in fetal programming induced rat model after amlodipine-losartan combination treatment.

BackgroundThere are a number of complications that can occur if there is under-nutrition during pregnancy followed by a period of rapid catch-up growth, including a higher chance of adult obesity, insulin resistance and hypertriglyceridemia. The purposes of this study were to investigate the effects of fetal under-nutrition during late pregnancy and lactation on blood pressure, visceral fat tissue, gene expressions and to evaluate changes after amlodipine- losartan combination treatment.MethodsThe rats were divided into three groups: the control (C) group, the food restriction (FR: 50 % food restricted diet) group, and the CX group, which was treated with Cozaar XQ (amlodipine- losartan combination drug) in FR rats from postnatal 4 to 20 weeks. Masson’s trichrome staining was performed in the heart tissues. The amount of abdominal visceral fat tissues was measured. Western blot analysis such as angiotensin converting enzyme (ACE), angiotensin II receptor type IA (ATIA), troponin I (Tn I) and endothelial nitric oxide synthase (eNOS) were performed.ResultsBody weights were significantly higher in the FR group compared with the C group at weeks 8 and 20 and lower in the CX group at week 20. Blood pressure was significantly higher in the FR group compared with the C group at week 20 and lower in the CX group at weeks 12 and 20. The amount of abdominal visceral fat was significantly higher in the FR group compared with the C group at weeks 8, 12 and 20 and significantly lower in the CX group at weeks 16 and 20. Protein expression of ATIA and eNOS were significantly reduced in the CX group at weeks 16 and 20. ACE was significantly reduced in the CX group at week 20 and Tn I was significantly reduced in the CX group at week 16.ConclusionsWhen there is fetal under-nutrition during pregnancy, it leads to obesity, high blood pressure, hypertriglyceridemia and several gene changes in offspring. Amlodipine-losartan combination treatment was able to lower obesity, hypertension, hypertriglyceridemia and several gene changes in rats suffering from fetal under-nutrition during pregnancy.

Glomerular filtration barrier in rat offspring exposed to maternal undernutrition

Poor diet during pregnancy can increase blood pressure in offspring of human and laboratory animals. The present study examined the effects of moderate intrauterine undernutrition on the ultrastructure of the glomerular filtration barrier in 20-day-old rat fetuses and six-month-old rat offspring. Pregnant rats were provided with either ad libitum food during pregnancy (control group, C) or restricted to 50% of ad libitum food until delivery (food-restricted group, FR). Both groups were given free access to food after birth. The kidneys of embryonic day 20 and six-month-old rats were harvested. Transmission electron micrographs in glomeruli from both groups were obtained to study the ultrastructure of the glomerular filtration barrier. Blood pressure and glomerular filtration rate were measured in six-month-old rats. In comparison to the control group, the FR group had smaller body and kidney weights in both ages. Systemic blood pressure was significantly elevated in the FR group. The glomerular filtration rate was similar in both groups. A study of the glomerular ultrastructure showed a remarkable retardation in the development of the podocyte foot process in the FR group at embryonic day 20. Micrographs also showed remarkable changes in the glomerular filtration barrier of six-month-old rats including an increase in the thickness of the glomerular basement membrane and an increase in the width of filtration slits. These results suggest that maternal food restriction disturbs the development of the glomerular filtration barrier, which may contribute to hypertension in adult rat offspring. The long-term exposure to hypertension and glomerular hyperfiltration may have contributed to the damages observed in the glomerular filtration barrier of six-month-old rats exposed to intrauterine food restriction.

Catch-up growth following food restriction exacerbates adulthood glucose intolerance in pigs exposed to intrauterine undernutrition

ObjectiveThe aim of this study was to evaluate the effects of food restriction followed by controlled refeeding on glucose tolerance in pigs exposed to intrauterine malnutrition. MethodsPregnant sows (n = 11) were assigned to either a control (C) group or an undernutrition (U) group (75% of C) during gestation. At postnatal 68 d, the offspring (n = 16) were placed on either a cafeteria feeding (CF) group or a food-restricted (FR) group (75% of CF) for 6 wk. After that, all offspring were fed ad libitum until 189 d (dpn189). ResultsThe results showed that maternal malnutrition induced offspring glucose intolerance, which was demonstrated by increased serum glucose and triacylglycerol content at dpn189, as well as increased area under the blood glucose curve (AUC) during the intravenous glucose tolerance test (i.v.GTT) (P < 0.05). Interestingly, food restriction followed by controlled refeeding further increased serum glucose content at dpn189 and AUC during i.v.GTT in pigs born from U sows (P < 0.05), which was accompanied by catch-up growth during the refeeding period. These changes were associated with increased mRNA levels of hepatic gluconeogenesis (PC, PEPCK) enzymes (P < 0.05), decreased mRNA level of muscle glucose transporter (GLUT4; P = 0.07), and reduced mRNA level of insulin signaling protein (IRS1, P < 0.05) in the liver. ConclusionsOur results indicate that catch-up growth following food restriction can exacerbate glucose intolerance in offspring exposed to intrauterine malnutrition. This may be caused by increased hepatic gluconeogenesis, decreased muscle glucose transport, and impaired hepatic insulin signaling.

Prenatal undernutrition results in greater lipopolysaccharide-induced changes in hypothalamic TNF-α expression, but does not affect the equivalent changes in the serum levels of luteinizing hormone and testosterone, in adult male rats

Immune stress can cause reproductive dysfunction. Some hypothalamic factors such as pro-inflammatory cytokines play pivotal roles in reproductive disorders under immune stress conditions. Recently, it has been reported that prenatal undernutrition affects not only metabolic functions, but also the responses of physiological functions to immune stress in adulthood. In this study, the long-term effects of prenatal undernutrition on the responses of hypothalamic pro-inflammatory cytokine (interleukin (IL)-1β, tumor necrosis factor (TNF)-α, and IL-6) expression; reproductive endocrine factors; i.e., the serum levels of gonadotropins and testosterone; and hypothalamic kisspeptin expression to lipopolysaccharide (LPS) were examined in male rats. Pregnant rats were divided into two groups; i.e., the normally nourished group and the undernourished (50% food restricted) group. The offspring of the normally nourished mothers (control) and undernourished mothers (the intrauterine growth restriction [IUGR] group) were sub-divided into saline-injected and LPS (500μg, i.p.)-injected groups at 10 weeks of age. The rats’ hypothalamic pro-inflammatory cytokine levels and serum luteinizing hormone (LH) and testosterone levels were measured and compared between the control and IUGR groups. The hypothalamic pro-inflammatory cytokine mRNA levels of the LPS-injected rats were significantly higher than those of the saline-injected rats in both the control and IUGR groups. The changes in the hypothalamic expression level of TNF-α, but not those of the other cytokines, induced in response to LPS were more marked in the IUGR group than in the control group. On the other hand, although the serum LH and testosterone levels of the LPS-injected rats were significantly lower than those of the saline-injected rats in both the control and IUGR groups, their levels did not differ between the control and IUGR groups under the LPS-injected conditions. These results suggest that prenatal undernutrition results in more marked LPS-induced changes in hypothalamic TNF-α expression, but does not alter the effects of LPS on the serum levels of LH or testosterone, in adult male rats.

The Preventive Effect of Calcium Supplementation on Weak Bones Caused by the Interaction of Exercise and Food Restriction in Young Female Rats During the Period from Acquiring Bone Mass to Maintaining Bone Mass.

Increasing calcium (Ca) intake is important for female athletes with a risk of weak bone caused by inadequate food intake. The aim of the present study was to examine the preventive effect of Ca supplementation on low bone strength in young female athletes with inadequate food intake, using the rats as an experimental model. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feeding group (EX), voluntary running exercise and 30% food restriction group (EX-FR), and a voluntary running exercise, 30% food-restricted and high-Ca diet group (EX-FR+Ca). To Ca supplementation, we used 1.2% Ca diet as "high-Ca diet" that contains two-fold Ca of normal Ca diet. The experiment lasted for 12 weeks. As a result, the energy availability, internal organ weight, bone strength, bone mineral density, and Ca absorption in the EX-FR group were significantly lower than those in the EX group. The bone strength and Ca absorption in the EX-FR+Ca group were significantly higher than those in the EX-FR group. However, the bone strength in the EX-FR+Ca group did not reach that in the EX group. These results suggested that Ca supplementation had a positive effect on bone strength, but the effect was not sufficient to prevent lower bone strength caused by food restriction in young female athletes.

Food Restriction Prolongs Murine Cardiac Grafts

Overeating and obesity lead to cardiovascular disease, diabetes, and eventually premature death, whereas food or energy restriction reduces risk factors for cardiovascular disease and diabetes and expands the life span. The aim of this study was to investigate the effect of food restriction (FR) in a murine heart transplant model. CBA male recipients (H2k) that underwent transplantation of C57BL/6 (H2b) hearts were assigned to free access group or FR groups with food intake at 60% (40% FR), 50% (50% FR), or 40% (60% FR) of the average food intake for 1 week after transplantation, and each median survival time was measured. We also performed cell proliferation, cytokine production, and flow cytometry assessments. The 60% FR CBA recipients showed prolongation of allograft survival (median survival time, 24 days). Cell proliferation and interferon-γ were suppressed in the 60% FR CBA recipients. Flow cytometry studies showed a lower CD4+CD25+Foxp3+ cell population in splenocytes from the 60% FR CBA recipients. In conclusion, the findings suggest that the prolongation of cardiac allograft resulted from not regulation of alloimmune responses, but partial impairment of alloimmune responses, linking energy restriction to low generation of splenic CD4+CD25+Foxp3+ regulatory T cells.

Impact of Early Postnatal NSAID Treatment on Nephrogenesis in Wistar Rats

Prematurely born children with patent ductus arteriosus are treated with ibuprofen or indomethacin, which may inhibit kidney development. We determined whether clinical doses affected kidney development and function, with or without extrauterine growth retardation. Wistar rats were cross-fostered in normal food (NF) or food restricted (FR) litters at postnatal day (PND) 2. On PND 3 to 4, three doses of 0.9% NaCl, 0.1 mg/kg indomethacin, or 10 mg/kg ibuprofen were administered via intraperitoneal injection with 12-hr intervals. Kidneys were evaluated for apoptosis, proliferation, and gene expression at PND 8; stereological assessment of nephron number at PND 35; and clinical pathology and neutrophil gelatinase-associated lipocalin at 4 and 9 months. Blood pressure was measured at the ages of 4, 6, and 9 months. NF and FR bodyweight differed from PND 3 onwards, ranging from 16.5 g at weaning (p < 0.001) to 39 g at necropsy (p = 0.019). Kidney proliferation/apoptosis ratios were 7:1 and 3:1 (p = 0.001), respectively and different expression of Wnt4 (0.7x), Oat1 (1.3x), Nphs1 (1.7x), and Aqp4 (1.3x) was noted (but its biological relevance doubted). Nephron numbers were decreased by 12% (p = 0.109) in the ibuprofen-NF group and 7.5% (p = 0.237) in FR groups. This coincided with a tendency to increased neutrophil gelatinase-associated lipocalin at 9 months. No differences were noted in electrolytes, creatinine, or urea clearance. No valid blood pressure results could be obtained. A clinical Ibuprofen dose showed potential to inhibit kidney development in neonatal rats. FR did not modulate these effects.

The Interaction of Voluntary Running Exercise and Food Restriction Induces Low Bone Strength and Low Bone Mineral Density in Young Female Rats.

There is a concern that the combination of exercise with food intake reduction has a risk of reducing bone strength and bone mass in young female athletes. We examined the influence of the interaction of voluntary running exercise and food restriction on bone in young female rats. Seven-week-old female Sprague-Dawley rats were divided into four groups: the sedentary and ad libitum feeding group (SED), voluntary running exercise and ad libitum feeding group (EX), sedentary and 30 % food restriction group (SED-FR), and voluntary running exercise and 30 % food restriction group (EX-FR). The experiment lasted 12 weeks. Statistical analysis was carried out by two-way analysis of variance with exercise and restriction as the between-subjects factors. As a result, there were significant interactions of running and restriction on energy availability, breaking force, breaking energy, and bone mineral density (BMD). Breaking force and energy in the EX group were significantly higher than in the SED group; breaking force and energy were significantly lower in the EX-FR group than in the EX group, and breaking force in the EX-FR group was significantly lower than that in the SED-FR group. BMD in the EX-FR group was significantly lower than in the EX and SED-FR groups. These results suggest that food restriction induced low bone strength in young female rats engaging in voluntary running exercise. Also, through the interaction of exercise and food restriction, voluntary running exercise combined food restriction, unlike ad libitum feeding conditions, induced low bone strength, and low BMD in young female rats.

Intrauterine growth restriction increases the preference for palatable foods and affects sensitivity to food rewards in male and female adult rats

Clinical evidence suggests that intrauterine growth restriction (IUGR) can cause persistent changes in the preference for palatable foods. In this study, we compared food preferences, the response to food rewards, and the role of the mesolimbic dopaminergic system in feeding behavior, between IUGR and control rats. Time-mated pregnant Sprague–Dawley rats were randomly allocated to a control group (standard chow ad libitum) or a 50% food restriction (FR) group, which received 50% of the control dams׳ habitual intake. These diets were provided from gestation day 10 to the 21st day of lactation. Within 24h of birth, pups were cross-fostered and divided into four groups: Adlib/Adlib, FR/Adlib, FR/FR, Adlib/FR. Standard chow consumption was compared between all groups. Food preferences, conditioned place preference to a palatable diet, and the levels of tyrosine hydroxylase (TH) phosphorylation and D2 receptors in the nucleus accumbens were analyzed and compared between the two groups of interest: Adlib/Adlib (control) and FR/Adlib (exposed to growth restriction during the fetal period only). IUGR adult rats had a stronger preference for palatable foods, but showed less conditioned place preference to a palatable diet than controls. D2 receptors levels were lower in IUGR rats. At baseline, TH and pTH levels were higher in FR/Adlib than control males. Measurements taken after exposure to sweet foods revealed higher levels of TH and pTH in FR/Adlib than control females. These data showed that IUGR rats exhibited a preference for palatable foods, potentially due to alterations in their mesolimbic reward pathway. Additionally, the changes observed in the mesolimbic dopaminergic system of IUGR rats proved to be sex-specific.This article is part of a Special Issue entitled 1618.

Proteomic analysis of fetal programming-related obesity markers.

The objectives of this study were to analyze fetal programming in rat brain using proteomic analysis and to identify fetal programming-related obesity markers. Sprague-Dawley rats were divided into four feeding groups: (i) the Ad Libitum (AdLib)/AdLib group was given a normal diet during pregnancy and the lactation period; (ii) the AdLib/maternal food restriction group (FR) was subjected to 50% FR during the lactation period; (iii) the FR/AdLib group was subjected to 50% FR during pregnancy; and (iv) the FR/FR group was subjected to 50% FR during pregnancy and the lactation period. Offspring from each group were sacrificed at 3 weeks of age and whole brains were dissected. To obtain a maximum number of protein markers related to obesity, 2DE and Pathway Studio bioinformatics analysis were performed. The identities of the markers among the selected and candidate proteins were confirmed by Western blotting and immunohistochemistry. Proteomic and bioinformatics analyses revealed that expression of ubiquitin carboxy-terminal hydrolase L1 (UCHL1) and Secernin 1 (SCRN1) were significantly different in the FR/AdLib group compared with the AdLib/AdLib group for both male and female offspring. These findings suggest that UCHL1 and SCRN1 may be used as fetal programming-related obesity markers.

The number of preproghrelin mRNA expressing cells is increased in mice with activity-based anorexia

Plasma levels of ghrelin, an orexigenic peptide, are increased during conditions of chronic starvation, such as in patients with anorexia nervosa. However, it is not known whether such increase can be related to the number of preproghrelin mRNA-expressing cells in the stomach, and if chronic starvation may activate a tentative central ghrelin production. In this work, in situ hybridization technique was used to analyze the presence and number of preproghrelin mRNA-expressing cells in the stomach and the hypothalamus of mice with activity-based anorexia (ABA) induced by the combination of running wheel activity with progressive, during 10 days, feeding-time restriction (FTR) and compared with sedentary FTR, ABA pair-fed (PF) and ad libitum-fed control mice. All food-restricted mice lost more than 20% of body weight. Body weight loss was similar in ABA and PF mice, but it was more pronounced than in FTR mice. Food intake was also lower in ABA than in FTR mice. Preproghrelin mRNA-expressing cells in the stomach were increased proportionally to the body weight loss in all food-restricted groups with the highest number in ABA mice. No preproghrelin mRNA-producing cells were detectable in the hypothalamus of either control or food-restricted mice. Thus, the increased number of gastric preproghrelin mRNA-producing cells during chronic starvation proportionally to the body weight loss and reduced food intake may underlie increased plasma ghrelin. Hyperactivity-induced anorexia appears to further increase the number of preproghrelin mRNA-producing cells in the stomach. No evidence was found for ghrelin expression in the hypothalamus, not even in any of the present experimental models.

Metabolic Effects of Temporally Targeted Food Restriction in Female Rats with or without Estrogen

To lose weight, overweight people limit calories by reducing food intake and/or number of meals, typically eating in the evening when activity is less. We use rats to model this pattern by providing food for 2 hr/day during the inactive period. In previous work, estrogen decreased body weight and food intake during temporally targeted food restriction as it does during ad libitum feeding. Thus, the goal of this study was to investigate mechanisms that underlie estrogen effects on feeding during temporally targeted food restriction. Ovariectomized rats were given estradiol benzoate (EB) or vehicle twice weekly for 3 wks of ad libitum feeding, or for 2 wks of ad libitum feeding followed by 1 wk of access to food for only 2 hr/d. On the last day of food restriction, some rats were allowed to eat before sacrifice (FED) and others were not (FASTED). Rats then were sacrificed to collect blood, livers, adrenals, and uteri. In both hormone groups, 1-hr food intake increased during targeted food restriction; however EB-treated rats ate less. Insulin and leptin were reduced in FASTED rats in both hormone groups. Liver glycogen was elevated in ad libitum rats of both hormone groups but decreased in both FED and FASTED food restricted groups. Glucose was reduced, while triglycerides and free fatty acids were elevated in EB-treated rats that were food restricted. Adrenal weights and plasma corticosterone were greater in EB-treated rats, but increased in both groups with food restriction, suggesting that temporally targeted restriction is a potent stressor. Together, these results suggest that EB influences metabolic patterns during temporally targeted food restriction, which may contribute to EB effects on eating and body weight during that restriction. Support: OCAST HR12-196

Potential biomarkers of fatigue identified by plasma metabolome analysis in rats.

In the present study, prior to the establishment of a method for the clinical diagnosis of chronic fatigue in humans, we validated the utility of plasma metabolomic analysis in a rat model of fatigue using capillary electrophoresis-mass spectrometry (CE-MS). In order to obtain a fatigued animal group, rats were placed in a cage filled with water to a height of 2.2 cm for 5 days. A food-restricted group, in which rats were limited to 10 g/d of food (around 50% of the control group), was also assessed. The food-restricted group exhibited weight reduction similar to that of the fatigued group. CE-MS measurements were performed to evaluate the profile of food intake-dependent metabolic changes, as well as the profile in fatigue loading, resulting in the identification of 48 metabolites in plasma. Multivariate analyses using hierarchical clustering and principal component analysis revealed that the plasma metabolome in the fatigued group showed clear differences from those in the control and food-restricted groups. In the fatigued group, we found distinctive changes in metabolites related to branched-chain amino acid metabolism, urea cycle, and proline metabolism. Specifically, the fatigued group exhibited significant increases in valine, leucine, isoleucine, and 2-oxoisopentanoate, and significant decreases in citrulline and hydroxyproline compared with the control and food-restricted groups. Plasma levels of total nitric oxide were increased in the fatigued group, indicating systemic oxidative stress. Further, plasma metabolites involved in the citrate cycle, such as cis-aconitate and isocitrate, were reduced in the fatigued group. The levels of ATP were significantly decreased in the liver and skeletal muscle, indicative of a deterioration in energy metabolism in these organs. Thus, this comprehensive metabolic analysis furthered our understanding of the pathophysiology of fatigue, and identified potential diagnostic biomarkers based on fatigue pathophysiology.