Voluntary exercise, food intake, and plasma metabolites in streptozotocin-diabetic Syrian hamsters

During pregnancy or after experimental manipulations of ovarian hormone levels, Syrian hamsters exhibit changes in energy balance and body fat content without modifying their food intake. The present experiments determined whether fluctuations in voluntary exercise play a role in these changes in energy balance, as they appear to do in other species. As expected, pregnant hamsters maintained a constant level of food intake and lost approximately 40% of their body fat. These animals did not show the abrupt decrease in activity after mating that is seen in rats. Instead, they maintained their high, premating level of running wheel activity until the last 3 days of pregnancy. Similarly, ovariectomy and replacement therapy with estradiol or estradiol+progesterone caused substantial changes in energy balance in the absence of significant changes in food intake or running wheel activity. These findings indicate that, unlike rats, Syrian hamsters do not exhibit substantial changes in voluntary exercise during pregnancy or in response to manipulations of ovarian steroid levels. Therefore, neither changes in food intake nor in voluntary exercise play any important role in the pregnancy- or steroid-induced changes in energy balance in Syrian hamsters.

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Central GABAA receptor mediates taurine-induced hypothermia and possibly reduces food intake in thermo-neutral chicks and regulates plasma metabolites in heat-exposed chicks

Journal of Thermal Biology ◽

10.1016/j.jtherbio.2021.102905 ◽

2021 ◽

pp. 102905

Author(s):

Mohamed Z. Elhussiny ◽

Phuong V. Tran ◽

Cuong V. Pham ◽

Linh T.N. Nguyen ◽

Shogo Haraguchi ◽

...

Keyword(s):

Food Intake ◽

Gabaa Receptor ◽

Plasma Metabolites ◽

Induced Hypothermia

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Different Short-Term Mild Exercise Modalities Lead to Differential Effects on Body Composition in Healthy Prepubertal Male Rats

BioMed Research International ◽

10.1155/2015/404201 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 3

Author(s):

D. M. Sontam ◽

M. H. Vickers ◽

J. M. O’Sullivan ◽

M. Watson ◽

E. C. Firth

Keyword(s):

Body Composition ◽

Food Intake ◽

Vital Role ◽

Voluntary Exercise ◽

Bone Architecture ◽

Male Rats ◽

Short Term ◽

Cross Sectional ◽

Impact Exercise ◽

Prepubertal Rats

Physical activity has a vital role in regulating and improving bone strength. Responsiveness of bone mass to exercise is age dependent with the prepubertal period suggested to be the most effective stage for interventions. There is a paucity of data on the effects of exercise on bone architecture and body composition when studied within the prepubertal period. We examined the effect of two forms of low-impact exercise on prepubertal changes in body composition and bone architecture. Weanling male rats were assigned to control (CON), bipedal stance (BPS), or wheel exercise (WEX) groups for 15 days until the onset of puberty. Distance travelled via WEX was recorded, food intake measured, and body composition quantified. Trabecular and cortical microarchitecture of the femur were determined by microcomputed tomography. WEX led to a higher lean mass and reduced fat mass compared to CON. WEX animals had greater femoral cortical cross-sectional thickness and closed porosity compared to CON. The different exercise modalities had no effect on body weight or food intake, but WEX significantly altered body composition and femoral microarchitecture. These data suggest that short-term mild voluntary exercise in normal prepubertal rats can alter body composition dependent upon the exercise modality.

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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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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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Effects of the fructose analog, 2,5-anhydro-D-mannitol, on food intake and estrous cyclicity in Syrian hamsters

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1997.272.3.r935 ◽

1997 ◽

Vol 272 (3) ◽

pp. R935-R939

Author(s):

J. E. Schneider

Keyword(s):

Food Intake ◽

Plasma Glucose ◽

Acid Oxidation ◽

Estrous Cycles ◽

Syrian Hamsters ◽

Glucose Levels ◽

Fuel Metabolism ◽

Increase Food Intake ◽

Estrous Cyclicity ◽

Estrous Cycling

Hyperphagia and anovulation are both triggered by prior food deprivation or other treatments that decrease intracellular availability of metabolic fuels in most species studied. Syrian hamsters fail to show compensatory hyperphagia, but do show anestrus in response to these energetic challenges. In the present experiments, we examined food intake, plasma glucose levels, and estrous cyclicity in Syrian hamsters in response to 2,5-anhydro-D-mannitol (2,5-AM), a fructose analog that is thought to trigger eating in rats by depleting intracellular levels of ATP. In experiment 1, female estrous cycling hamsters were treated with 100, 200, 400, or 800 mg/kg 2,5-AM or the vehicle by intraperitoneal injection. Food intake was measured 1, 2, 4, 8, and 24 h after treatment. There were no statistically significant increases in food intake in response to any dose of 2,5-AM. In experiment 2, blood samples were drawn at 0, 1, 3, 5, 7, and 25 h after hamsters were treated with 0 or 400 mg/kg 2,5-AM. 2,5-AM treatment resulted in a mild but significant decrease in plasma glucose levels similar to those seen in 2,5-AM-treated rats, suggesting that 2,5-AM has similar effects on fuel metabolism in rats and hamsters. In experiment 3, hamsters received 2,5-AM, 2,5-AM plus the fatty acid oxidation inhibitor methyl palmoxirate, or vehicle every 6 h over the first 48 h of the estrous cycle and were tested for indexes of estrous cyclicity at the end of the cycle. All hamsters showed normal estrous cycles, regardless of treatment. If 2,5-AM has similar metabolic consequences in rats and hamsters, the present results suggest that decreased intracellular levels of ATP and mild hypoglycemia do not increase food intake or inhibit estrous cyclicity in Syrian hamsters.

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Neuropeptide Y inhibits estrous behavior and stimulates feeding via separate receptors in Syrian hamsters

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.2001.280.4.r1061 ◽

2001 ◽

Vol 280 (4) ◽

pp. R1061-R1068 ◽

Cited By ~ 25

Author(s):

Eric S. Corp ◽

Beatrice Gréco ◽

J. Bradley Powers ◽

Carrie L. Marín Bivens ◽

George N. Wade

Keyword(s):

Food Intake ◽

Neuropeptide Y ◽

Feeding Behavior ◽

Sexual Behaviors ◽

Peptide Yy ◽

Receptor Subtypes ◽

Syrian Hamsters ◽

Total Food Intake ◽

Npy Receptor ◽

Estrous Behavior

Central injections of neuropeptide Y (NPY) increase food intake in Syrian hamsters; however, the effect of NPY on sexual behavior in hamsters is not known nor are the receptor subtypes involved in feeding and sexual behaviors. We demonstrate that NPY inhibits lordosis duration in a dose-related fashion after lateral ventricular injection in ovariectomized, steroid-primed Syrian hamsters. Under the same conditions, we compared the effect of two receptor-differentiating agonists derived from peptide YY (PYY), PYY-(3–36) and [Leu31,Pro34]PYY, on lordosis duration and food intake. PYY-(3–36) produced a 91% reduction in lordosis duration at 0.24 nmol. [Leu31,Pro34]PYY was less potent, producing a reduction in lordosis duration (66%) only at 2.4 nmol. These results suggest NPY effects on estrous behavior are principally mediated by Y2 receptors. PYY-(3–36) and [Leu31,Pro34]PYY stimulated comparable dose-related increases in total food intake (2 h), suggesting Y5 receptors are involved in feeding. The significance of different NPY receptor subtypes controlling estrous and feeding behavior is highlighted by results on expression of Fos immunoreactivity (Fos-IR) elicited by either PYY-(3–36) or [Leu31,Pro34]PYY at a dose of each that differentiated between the two behaviors. Some differences were seen in the distribution of Fos-IR produced by the two peptides. Overall, however, the patterns of expression were similar. Our behavioral and anatomic results suggest that NPY-containing pathways controlling estrous and feeding behavior innervate similar nuclei, with the divergence in pathways controlling the separate behaviors characterized by linkage to different NPY receptor subtypes.

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Dorsomedial hypothalamic corticotropin-releasing factor mediation of exercise-induced anorexia

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00805.2004 ◽

2005 ◽

Vol 288 (6) ◽

pp. R1800-R1805 ◽

Cited By ~ 54

Author(s):

Maiko Kawaguchi ◽

Karen A. Scott ◽

Timothy H. Moran ◽

Sheng Bi

Keyword(s):

Gene Expression ◽

Body Weight ◽

Food Intake ◽

Mrna Expression ◽

Critical Role ◽

Voluntary Exercise ◽

Running Wheel ◽

Exercise Induced ◽

Running Wheels ◽

Induced Changes

Running wheel access and resulting voluntary exercise alter food intake and reduce body weight. The neural mechanisms underlying these effects are unclear. In this study, we first assessed the effects of 7 days of running wheel access on food intake, body weight, and hypothalamic gene expression. We demonstrate that running wheel access significantly decreases food intake and body weight and results in a significant elevation of CRF mRNA expression in the dorsomedial hypothalamus (DMH) but not the paraventricular nucleus. Seven-day running wheel access also results in elevated arcuate nucleus and DMH neuropeptide Y gene expression. To assess a potential role for elevated DMH CRF activity in the activity-induced changes in food intake and body weight, we compared changes in food intake, body weight, and hypothalamic gene expression in rats receiving intracerebroventricular (ICV) CRF antagonist α-helical CRF or vehicle with or without access to running wheels. During a 4-day period of running wheel access, we found that exercise-induced reductions of food intake and body weight were significantly attenuated by ICV injection of the CRF antagonist. The effect on food intake was specific to a blockade of activity-induced changes in meal size. Central CRF antagonist injection further increased DMH CRF mRNA expression in exercised rats. Together, these data suggest that DMH CRF play a critical role in the anorexia resulting from increased voluntary exercise.

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