Effect of saccharin supplementation on weight gain, caloric intake and basal oxygen consumption in Wistar rats

Chronic electrical vagal nerve stimulation (VNS) has emerged as a new tool to treat human diseases including obesity. Indeed, chronic VNS has been shown to cause weight loss in humans and in experimental animal models. However, the mechanisms for VNS-induced weight loss are largely unknown. We hypothesized that an increase in metabolic rate together with reduced caloric intake and reduced feeding efficiency (body weight gain per calories consumed) contribute to chronic VNS-induced weight loss or reduced weight gain. To test this hypothesis, we developed a miniaturized microprocessor-operated nerve stimulator for chronic use in conscious mice. Effectiveness of the stimulator was verified by bradycardia at stimulation frequencies above 5 Hz (3V, 1mA, 1ms pulses). Male C57Bl/6 mice (16 weeks old, standard mouse chow diet) were instrumented with nerve stimulators (3V, 1mA, 1ms pulses at 5 Hz) on the right cervical vagal nerve and body weight, food intake and metabolic rate (indirect calorimetry) were determined at baseline and weekly thereafter. After the initial post-surgical weight loss, sham animals (n=9, stimulators off) regained pre-surgical body weight within 16 days (100.0±2.7%). In contrast, mice with chronic VNS (n=12) never reestablished pre-surgical body weight (94.5±0.9% on day 16, P<0.05 vs. sham). Caloric intake was significantly reduced in mice with chronic VNS compared to sham animals (74.7±2.4 vs. 84.6±4.2 kcal/week, P<0.05). Likewise, mice with chronic VNS showed significantly reduced feeding efficiency compared to sham mice (2.6±2.0 vs. 10.6±2.4 mg body weight gain per kcal consumed). Oxygen consumption tended to be elevated (2734±152 vs. 2490±124 mL/kg/h, P=0.23) during the first week, but not thereafter. In conclusion reduced food intake and lower feeding efficiency contribute to reduced weight gain in mice with chronic VNS. We speculate that an initial increase in metabolic rate (assessed by oxygen consumption) may be antagonized by compensatory mechanisms in response to chronic VNS.

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Abstract 512: Anorectic and Thermogenic Effects of Chronic Vagal Nerve Stimulation in Mice

Hypertension ◽

10.1161/hyp.64.suppl_1.512 ◽

2014 ◽

Vol 64 (suppl_1) ◽

Author(s):

Daniel P Dias ◽

Donald A Morgan ◽

Harald M Stauss ◽

Kamal Rahmouni

Keyword(s):

Weight Loss ◽

Body Weight ◽

Oxygen Consumption ◽

Weight Gain ◽

Food Intake ◽

Metabolic Rate ◽

Body Weight Gain ◽

Caloric Intake ◽

Vagal Nerve ◽

Feeding Efficiency

Electrical vagal nerve stimulation (VNS) has emerged as a new tool to treat human diseases including obesity. Indeed, chronic VNS has been shown to cause weight loss in humans and in experimental animal models. However, the mechanisms by which chronic VNS causes weight loss are largely unknown due in part to the unavailability of implantable nerve stimulators for mice excluding the use of genetically engineered mouse models to investigate these mechanisms. Identification such mechanisms promises to identify novel approaches for weight loss. Here, we report the development of a miniaturized microprocessor-operated nerve stimulator for chronic use in conscious mice. Effectiveness of the stimulator was verified by the bradycardia induced at stimulation frequencies above 5 Hz (3V, 1mA, 1ms pulses). Next, we used the stimulator to test whether changes in metabolic rate, caloric intake and feeding efficiency (body weight gain per calories consumed) contribute to chronic VNS-induced weight loss. Male C57Bl/6 mice (16 weeks old, on standard mouse chow diet) were instrumented with nerve stimulators (3V, 1mA, 1ms pulses at 5 Hz) on the right cervical vagal nerve and body weight, food intake and metabolic rate (indirect calorimetry) were determined at baseline and weekly thereafter. After the initial post-surgical weight loss, sham animals (n=9, stimulators off) regained pre-surgical body weight within 16 days (100.0±2.7%). In contrast, mice with chronic VNS (n=12) never re-established pre-surgical body weight (94.5±0.9% on day 16, P<0.05 vs. sham). Caloric intake was significantly reduced in mice with chronic VNS compared to sham group (74.7±2.4 vs. 84.6±4.2 kcal/week, P<0.05). Likewise, mice with chronic VNS showed significantly reduced feeding efficiency compared to sham mice (2.6±2.0 vs. 10.6±2.4 mg body weight gain per kcal consumed). Oxygen consumption tended to be elevated (2734±152 vs. 2490±124 mL/kg/h) during the first week, but not thereafter. In conclusion, reduced food intake and lower feeding efficiency contribute to VNS-induced weight loss in mice. We speculate that an initial increase in metabolic rate (assessed by oxygen consumption) may be antagonized by compensatory mechanisms triggered by chronic VNS.

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Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels

Appetite ◽

10.1016/j.appet.2012.10.009 ◽

2013 ◽

Vol 60 ◽

pp. 203-207 ◽

Cited By ~ 49

Author(s):

Fernanda de Matos Feijó ◽

Cíntia Reis Ballard ◽

Kelly Carraro Foletto ◽

Bruna Aparecida Melo Batista ◽

Alice Magagnin Neves ◽

...

Keyword(s):

Weight Gain ◽

Wistar Rats ◽

Caloric Intake ◽

Total Caloric Intake

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Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

Journal of Nutrition and Metabolism ◽

10.1155/2016/5168978 ◽

2016 ◽

Vol 2016 ◽

pp. 1-9 ◽

Cited By ~ 12

Author(s):

Elizabeth K. Parker ◽

Sahrish S. Faruquie ◽

Gail Anderson ◽

Linette Gomes ◽

Andrew Kennedy ◽

...

Keyword(s):

Eating Disorders ◽

Weight Gain ◽

Statistical Significance ◽

Caloric Intake ◽

Tube Feeding ◽

Retrospective Chart Review ◽

Refeeding Syndrome ◽

Restrictive Eating ◽

Weight Restoration ◽

The Mean

Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs) prescribed initial calories above current recommendations.Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review.Results. The mean (SD) age of the 162 adolescents was 16.7 years (0.9), admission % median BMI was 80.1% (10.2), and discharge % median BMI was 93.1% (7.0). The mean (SD) starting caloric intake was 2611.7 kcal/day (261.5) equating to 58.4 kcal/kg (10.2). Most patients (92.6%) were treated with nasogastric tube feeding. The mean (SD) length of stay was 3.6 weeks (1.9), and average weekly weight gain was 2.1 kg (0.8). No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (<0.75 mmol/L), 7% hypomagnesaemia (<0.70 mmol/L), and 2% hypokalaemia (<3.2 mmol/L). Caloric prescription on admission was associated with developing oedema (95% CI 1.001 to 1.047;p=0.039). No statistical significance was found between electrolytes and calories provided during refeeding.Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome.

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Changes in Health Behaviors Associated With Weight Gain by Weight Classification During the COVID-19 Pandemic

American Journal of Health Promotion ◽

10.1177/08901171211022958 ◽

2021 ◽

pp. 089011712110229

Author(s):

Kristie Rupp ◽

Ciarán P. Friel

Keyword(s):

Weight Gain ◽

Health Behaviors ◽

Weight Status ◽

Vegetable Consumption ◽

Caloric Intake ◽

Healthy Weight ◽

Cross Sectional ◽

Obesity Epidemic ◽

Logistic Regression Models ◽

Online Panels

Purpose: To determine whether perceived changes (i.e. perception of engagement during the pandemic relative to pre-pandemic) in specific health behaviors differ by weight status (i.e. healthy weight, overweight, obese). Design: Cross-sectional. Recruitment took place between June-August 2020, via social media posts and Qualtrics online panels. Setting: Participants completed the survey online through the Qualtrics platform. Sample: Analyses included N = 502 participants (≥18 years); 45.2% healthy weight (n = 227), 28.5% overweight (n = 143), and 26.3% obese (n = 132). Measures: Study-specific survey items included questions about demographics and perceived changes in health behaviors. Analysis: Logistic regression models, adjusted for age, race, ethnicity, gender, education, and COVID-19 diagnosis, assessed the odds of perceiving changes in health behaviors considered a risk for weight gain. Results: Participants with obesity, but not overweight, were significantly more likely to report deleterious changes to health behaviors compared to healthy weight peers, including: (1) decreased fruit/vegetable consumption [adjusted odds ratio (AOR) = 1.92; 95% confidence interval (CI): (1.13, 3.26)]; (2) increased processed food consumption [AOR = 1.85; 95%CI: (1.15, 3.00)]; (3) increased caloric intake [AOR = 1.66; 95% CI: (1.06, 2.61)]; (4) decreased physical activity [AOR = 2.07; 95%CI: (1.31, 3.28)]; and (5) deterioration in sleep quality [AOR = 2.07; 95%CI: (1.32, 3.25)]. Conclusion: Our findings suggest that adults with obesity may be at greater risk for unhealthy behaviors during a period of prolonged social distancing, potentially exacerbating the obesity epidemic.

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The effectiveness of early local administration of hyaluronic acid in experimental traumatic ischemia of the limb muscles

10.34014/mpphe.2021-246-249 ◽

2021 ◽

Author(s):

A.V. Shulepov ◽

I.A. Shperling ◽

Yu.V. Yurkevich ◽

N.V. Shperling

Keyword(s):

Oxygen Consumption ◽

Hyaluronic Acid ◽

Oxygen Saturation ◽

Wistar Rats ◽

Soft Tissues ◽

Local Administration ◽

Compression Injury ◽

Doppler Flowmetry ◽

Muscle Ischemia ◽

Male Wistar Rats

The experiments were performed on 280 male Wistar rats weighing 300-340 g. The design of the study included: modeling of compression injury of the soft tissues of the thigh, local injection of the preparation of hyaluronic acid "Gialift 3.5" into the area of damage 3 hours after the cessation of compression, taking into account the results after 7, 14 and 28 days. The introduction of hyaluronic acid into the area of compression injury of soft tissues reduces the severity of myoglobinemia, increases the immunohistochemical density of VEGF-positive cells, improves the perfusion characteristics of microcirculation, oxygen saturation, and specific oxygen consumption by tissues. Keywords: traumatic muscle ischemia, hyaluronic acid, myoglobin, microcirculation, metabolism, laser Doppler flowmetry, morphometry.

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Effect of the oral administration of monosodium glutamate during pregnancy and breast-feeding in the offspring of pregnant Wistar rats

Acta Cirurgica Brasileira ◽

10.1590/s0102-86502010000100010 ◽

2010 ◽

Vol 25 (1) ◽

pp. 37-42 ◽

Cited By ~ 4

Author(s):

Vinicius von Diemen ◽

Manoel Roberto Maciel Trindade

Keyword(s):

Weight Gain ◽

Oral Administration ◽

Wistar Rats ◽

Monosodium Glutamate ◽

The Other ◽

Control Group ◽

Pregnant Rats ◽

Dependent Relation ◽

Dose Dependent

PURPOSE: Determine the effects of the MSG (monosodium glutamate) in the offspring of pregnant rats through the comparison of the weight, NAL (nasal-anal length) and IL (Index of Lee) at birth and with 21 days of life. METHODS: Pregnant Wistar rats and their offspring were divided into 3 groups: GC, G10 and G20. Each of the groups received 0%, 10% and 20% of MSG, respectively from coupling until the end of the weaning period. RESULTS: Neither weight nor NAL were different among the groups at birth. The group G20 at birth had an IL lower than the group GC (p<0,05) and with 21 days of life presented weight and NAL lower than the groups G10 and this lower than the GC (p<0,01). Otherwise the G20 at 21 days of life had the IL similar to the other two groups. The weight profit percentage from birth to the 21st day of life was lower in the G20 regarding the other two groups (p<0,01). The G20 had a NAL increase percentage from birth to the 21st day of life lower than the G10 and this lower than the GC (p<0,01). CONCLUSIONS: MSG presented a dose-dependent relation in the variables weight and NAL. It caused a decrease in the growth pattern as well as in the weight gain pattern until the 21st day of life. The IL of the group 20% had an increased in relation to the control group after 3 weeks of follow up.

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STUDIES ON THE FORMATION OF COLLAGEN

Journal of Experimental Medicine ◽

10.1084/jem.107.2.265 ◽

1958 ◽

Vol 107 (2) ◽

pp. 265-277 ◽

Cited By ~ 56

Author(s):

Jerome Gross

Keyword(s):

Growth Rate ◽

Weight Gain ◽

Guinea Pigs ◽

Caloric Intake ◽

Neutral Salt ◽

Salt Solutions ◽

Citrate Buffer ◽

Continuous Growth ◽

Dermal Collagen ◽

Low Levels

The total amount of neutral salt-extractible collagen in the skin of growing, suckling guinea pigs amounted to about 10 per cent of the total collagen of the dennis. This is roughly equivalent to a 1 to 2 day increment in dermal collagen incident to growth. Fourteen days of static weight maintained by limited caloric intake reduced the neutral salt-extractible collagen to very low levels. Following this period, 5 to 7 days of steady weight gain induced by ad lib. feeding was required to produce significant increases in this collagen fraction. Return to control levels occurred within 12 days of continuous growth. The amount of collagen extracted from the dermis of young guinea pigs with cold neutral salt solutions varied directly with growth rate (weight gain) and was greatly diminished after short periods of restricted caloric intake. Two days of fasting diminished the total extracted collagen by one-half. Three consecutive extractions with citrate buffer pH, 3.5, of the residues remaining after exhaustive saline extraction removed 40 per cent more collagen from the skins of actively growing animals than from those of animals fasted for 2 days. However, subsequent extraction of residues with dilute acetic acid equalized the total amount of collagen extracted at acid pH from the two groups. The viscosity of cold neutral extracts was unrelated to the concentrations of non-collagenous proteins and carbohydrates but varied directly with the collagen content.

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Evaluation of Male Fertility-Enhancing Activities of Water Seed Extract of Hunteria umbellata in Wistar Rats

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2019/7693010 ◽

2019 ◽

Vol 2019 ◽

pp. 1-10

Author(s):

Adejuwon Adewale Adeneye ◽

Joseph Abayomi Olagunju ◽

Babatunde Adekunle Murtala

Keyword(s):

Weight Gain ◽

Vitamin C ◽

Male Fertility ◽

Wistar Rats ◽

Oral Treatment ◽

Seed Extract ◽

Distilled Water ◽

Hormonal Profile ◽

Group I ◽

Dose Dependent

Background. In this study, the male fertility-enhancing activity of 100, 200, and 400 mg/kg/day of Hunteria umbellata water seed extract (HU) in Wistar rats was studied for 60 days. In doing this, effect of repeated doses of HU was studied on the weight gain pattern, gonadosomatic index (GSI), serum follicle stimulating hormone (FSH), luteinizing hormone (LH), testosterone (TS), prolactin (PRL), and estradiol (ES)} as well as testicular antioxidant status of the treated rats as a way of elucidating the mechanism(s) of action of HU. Method. Thirty-six (36) male Wistar rats were randomly divided into six groups (I-VI) of six rats per group. Group I rats were gavaged with 10 ml/kg/day of distilled water and served as an untreated control; Group II rats were gavaged with 0.3 mg/kg/day of clomiphene in distilled water; Groups III-V rats received 100 mg/kg/day, 200 mg/kg/day, and 400 mg/kg/day of HU, respectively, and Group VI rats received 20 mg/kg/day of Vitamin C all in distilled water. All treatments were for 60 days after which the treated rats were humanely sacrificed. Sera of blood samples were processed for the above stated hormonal profile. Similarly, testicular tissues obtained were processed for semen analysis and complete antioxidant profile of the HU-treated testicles by assaying for superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH), glutathione reductase (GSR), glutathione peroxidase (GSH-Px), and Thiobarbituric Reactive Species (TBARS). Results. Prolonged treatments with 100 mg/kg/day, 200 mg/kg/day, and 400 mg/kg/day of HU for 60 days induced dose dependent reductions in weight gain pattern with the most significant (p<0.001) effect recorded with the highest dose of HU. Conversely, significant (p<0.001) increase was recorded for GSI at the same HU dose. Clomiphene and HU also induced significant (p<0.01, p<0.001) dose dependent increases in the total sperm count, %live sperm, but reverse effects on %dead sperm and %abnormal sperm. On the hormonal profile, oral treatment with 100 mg/kg/day, 200 mg/kg/day, and 400 mg/kg/day of the extract induced profound (p<0.05, p<0.01, and p<0.001) dose related increases in the sera TS, LH, and FSH while it caused reverse effect on serum PRL but caused no significant alterations in the serum ES levels. Similarly, oral treatment with vitamin C and 100-400 mg/kg/day of HU induced profound (p<0.05, p<0.01, and p<0.001) increases in the antioxidant enzyme activities. Conclusion. Overall, prolonged oral treatment with 100-400 mg/kg body weight of HU for 60 days significantly improved sperm function which was mediated via enhanced spermatogenesis, steroidogenesis, and antioxidant mechanisms.

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