scholarly journals The PYY/Y2R-Deficient Mouse Responds Normally to High-Fat Diet and Gastric Bypass Surgery

Nutrients ◽  
2019 ◽  
Vol 11 (3) ◽  
pp. 585 ◽  
Author(s):  
Brandon Boland ◽  
Michael Mumphrey ◽  
Zheng Hao ◽  
Benji Gill ◽  
R. Townsend ◽  
...  

Background/Goals: The gut hormone peptide YY (PYY) secreted from intestinal L-cells has been implicated in the mechanisms of satiation via Y2-receptor (Y2R) signaling in the brain and periphery and is a major candidate for mediating the beneficial effects of bariatric surgery on appetite and body weight. Methods: Here we assessed the role of Y2R signaling in the response to low- and high-fat diets and its role in the effects of Roux-en-Y gastric bypass (RYGB) surgery on body weight, body composition, food intake, energy expenditure and glucose handling, in global Y2R-deficient (Y2RKO) and wildtype (WT) mice made obese on high-fat diet. Results: Both male and female Y2RKO mice responded normally to low- and high-fat diet in terms of body weight, body composition, fasting levels of glucose and insulin, as well as glucose and insulin tolerance for up to 30 weeks of age. Contrary to expectations, obese Y2RKO mice also responded similarly to RYGB compared to WT mice for up to 20 weeks after surgery, with initial hypophagia, sustained body weight loss, and significant improvements in fasting insulin, glucose tolerance, insulin resistance (HOMA-IR), and liver weight compared to sham-operated mice. Furthermore, non-surgical Y2RKO mice weight-matched to RYGB showed the same improvements in glycemic control as Y2RKO mice with RYGB that were similar to WT mice. Conclusions: PYY signaling through Y2R is not required for the normal appetite-suppressing and body weight-lowering effects of RYGB in this global knockout mouse model. Potential compensatory adaptations of PYY signaling through other receptor subtypes or other gut satiety hormones such as glucagon-like peptide-1 (GLP-1) remain to be investigated.

Author(s):  
Brandon Boland ◽  
Michael B. Mumphrey ◽  
Zheng Hao ◽  
Benji Gill ◽  
R. Leigh Townsend ◽  
...  

Background/Goals: The gut hormone PYY secreted from intestinal L-cells has been implicated in the mechanisms of satiation via Y2-receptor (Y2R) signaling in the brain and periphery and is a major candidate for mediating the beneficial effects of bariatric surgery on appetite and body weight. Methods: Here we assessed the role of Y2R signaling in the response to low- and high-fat diets and its role in the effects of Roux-en-Y gastric bypass (RYGB) surgery on body weight, body composition, food intake, energy expenditure and glucose handling, in global Y2R-deficient (Y2RKO) and wildtype mice made obese on high-fat diet. Results: Both male and female Y2RKO mice responded normally to low- and high-fat diet in terms of body weight, body composition, fasting levels of glucose and insulin, as well as glucose and insulin tolerance for up to 30 weeks of age. Contrary to expectations, obese Y2RKO mice also responded similarly to RYGB compared to WT mice for up to 20 weeks after surgery, with initial hypophagia, sustained body weight loss, and significant improvements in fasting insulin, glucose tolerance, HOMA-IR, and liver weight compared to sham-operated mice. Furthermore, non-surgical Y2RKO mice weight-matched to RYGB showed the same improvements in glycemic control as Y2RKO mice with RYGB that were similar to WT mice. Conclusions: PYY signaling through Y2R is not required for the normal appetite-suppressing and body weight-lowering effects of RYGB in this global knockout mouse model. Potential compensatory adaptations of PYY signaling through other receptor subtypes or other gut satiety hormones such as GLP-1 remain to be investigated.


2014 ◽  
Vol 5 (3) ◽  
pp. 229-239 ◽  
Author(s):  
K. M. Platt ◽  
R. J. Charnigo ◽  
K. J. Pearson

Maternal high-fat diet consumption and obesity have been shown to program long-term obesity and lead to impaired glucose tolerance in offspring. Many rodent studies, however, use non-purified, cereal-based diets as the control for purified high-fat diets. In this study, primiparous ICR mice were fed purified control diet (10–11 kcal% from fat of lard or butter origin) and lard (45 or 60 kcal% fat) or butter (32 or 60 kcal% fat)-based high-fat diets for 4 weeks before mating, throughout pregnancy, and for 2 weeks of nursing. Before mating, female mice fed the 32 and 60% butter-based high-fat diets exhibited impaired glucose tolerance but those females fed the lard-based diets showed normal glucose disposal following a glucose challenge. High-fat diet consumption by female mice of all groups decreased lean to fat mass ratios during the 4th week of diet treatment compared with those mice consuming the 10–11% fat diets. All females were bred to male mice and pregnancy and offspring outcomes were monitored. The body weight of pups born to 45% lard-fed dams was significantly increased before weaning, but only female offspring born to 32% butter-fed dams exhibited long-term body weight increases. Offspring glucose tolerance and body composition were measured for at least 1 year. Minimal, if any, differences were observed in the offspring parameters. These results suggest that many variables should be considered when designing future high-fat diet feeding and maternal obesity studies in mice.


2014 ◽  
Vol 2014 ◽  
pp. 1-13 ◽  
Author(s):  
Rosa Martha Perez Gutierrez ◽  
Diana Madrigales Ahuatzi ◽  
Maria del Carmen Horcacitas ◽  
Efren Garcia Baez ◽  
Teresa Cruz Victoria ◽  
...  

Obesity is one of the major factors to increase various disorders like diabetes. The present paper emphasizes study related to the antiobesity effect ofPhalaris canariensisseeds hexane extract (Al-H) in high-fat diet- (HFD-) induced obese CD1 mice and in streptozotocin-induced mild diabetic (MD) and severely diabetic (SD) mice.AL-H was orally administered to MD and SD mice at a dose of 400 mg/kg once a day for 30 days, and a set of biochemical parameters were studied: glucose, cholesterol, triglycerides, lipid peroxidation, liver and muscle glycogen, ALP, SGOT, SGPT, glucose-6-phosphatase, glucokinase, hexokinase, SOD, CAT, GSH, GPX activities, and the effect on insulin level. HS-H significantly reduced the intake of food and water and body weight loss as well as levels of blood glucose, serum cholesterol, triglyceride, lipoprotein, oxidative stress, showed a protective hepatic effect, and increased HDL-cholesterol, serum insulin in diabetic mice. The mice fed on the high-fat diet and treated with AL-H showed inhibitory activity on the lipid metabolism decreasing body weight and weight of the liver and visceral adipose tissues and cholesterol and triglycerides in the liver. We conclude that AL-H can efficiently reduce serum glucose and inhibit insulin resistance, lipid abnormalities, and oxidative stress in MD and SD mice. Our results demonstrate an antiobesity effect reducing lipid droplet accumulation in the liver, indicating that its therapeutic properties may be due to the interaction plant components soluble in the hexane extract, with any of the multiple targets involved in obesity and diabetes pathogenesis.


2016 ◽  
Vol 61 (3) ◽  
pp. 1600716 ◽  
Author(s):  
Sandra Steensels ◽  
Leen Cools ◽  
Bert Avau ◽  
Laurien Vancleef ◽  
Ricard Farré ◽  
...  

Obesity ◽  
2014 ◽  
Vol 22 (10) ◽  
pp. 2147-2155 ◽  
Author(s):  
Yongbin Yang ◽  
Daniel L. Smith ◽  
Karen D. Keating ◽  
David B. Allison ◽  
Tim R. Nagy

2014 ◽  
Vol 306 (1) ◽  
pp. R34-R44 ◽  
Author(s):  
Beatriz de Carvalho Borges ◽  
Rodrigo Rorato ◽  
Ernane Torres Uchoa ◽  
Paula Marangon ◽  
Glauber S. F. da Silva ◽  
...  

Hypophagia induced by inflammation is associated with Janus kinase (JAK)-2/signal transducer and activator of transcription (STAT) 3 signaling pathway, and leptin-mediated hypophagia is also mediated by JAK2-STAT3 pathway. We have previously reported that lipopolysaccharide (LPS) did not reduce food intake in leptin-resistant high-fat diet (HFD) rats but maintained body weight loss. We investigated whether changes in p-STAT3 expression in the hypothalamus and brain stem could account for the desensitization of hypophagia in HFD animals after a low LPS dose (100 μg/kg). Wistar rats fed standard diet (3.95 kcal/g) or HFD (6.3 kcal/g) for 8 wk were assigned into control diet-saline, control diet-LPS, HFD-saline, and HFD-LPS groups. LPS reduced feeding in the control diet but not HFD. This group showed no p-STAT3 expression in the paraventricular nucleus (PVN) and ventromedial hypothalamic nucleus (VMH), but sustained, though lower than control, p-STAT3 in the nucleus of the solitary tract (NTS) and raphe pallidus (RPa). LPS decreased body weight in HFD rats and increased Fos expression in the NTS. LPS increased body temperature, oxygen consumption, and energy expenditure in both control diet and HFD rats, and this response was more pronounced in HFD-LPS group. Brown adipose tissue (BAT) thermogenesis and increased energy expenditure seem to contribute to body weight loss in HFD-LPS. This response might be related with increased brain stem activation. In conclusion, LPS activates STAT3-mediated pathway in the hypothalamus and brain stem, leading to hypophagia, however, LPS effects on food intake, but not body weight loss, are abolished by leptin resistance induced by HFD. The preserved STAT3 phosphorylation in the brain stem suggests that unresponsiveness to LPS on STAT3 activation under HFD might be selective to the hypothalamus.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Hyo Geun Kim ◽  
Hyun Uk Jeong ◽  
Gunhyuk Park ◽  
Hocheol Kim ◽  
Yunsook Lim ◽  
...  

Obesity has become a global health problem, contributing to various diseases including diabetes, hypertension, cancer, and dementia. Increasing evidence suggests that obesity can also cause neuronal damage, long-term memory loss, and cognitive impairment. The leaves and the fruits ofMorus albaL., containing active phytochemicals, have been shown to possess antiobesity and hypolipidemic properties. Thus, in the present study, we assessed their effects on cognitive functioning in mice fed a high-fat diet by performing immunohistochemistry, using antibodies against c-Fos, synaptophysin, and postsynaptic density protein 95 and a behavioral test. C57BL/6 mice fed a high-fat diet for 21 weeks exhibited increased body weight, but mice coadministered an optimized Mori Folium and Mori Fructus extract mixture (2 : 1; MFE) for the final 12 weeks exhibited significant body weight loss. Additionally, obese mice exhibited not only reduced neural activity, but also decreased presynaptic and postsynaptic activities, while MFE-treated mice exhibited recovery of these activities. Finally, cognitive deficits induced by the high-fat diet were recovered by cotreatment with MFE in the novel object recognition test. Our findings suggest that the antiobesity effects of MFE resulted in recovery of the cognitive deficits induced by the high-fat diet by regulation of neural and synaptic activities.


2021 ◽  
Vol 5 (Supplement_2) ◽  
pp. 1126-1126
Author(s):  
Weimin Guo ◽  
Dayong Wu ◽  
Lijun Li ◽  
Edwin Ortega ◽  
Yankun Liu ◽  
...  

Abstract Objectives Obesity is associated with impaired immune function. However, impact of obesity on blood T cell profile is not well studied. The objectives of this study were to investigate the effects of high fat diet (HFD)-induced obesity and long-term fruits and vegetable (FV) consumption on body composition and blood T cell profile. Methods This is partial report from an ongoing study. A total of 240 male C57BL/6J mice were randomly assigned to 4 groups: low fat control (LF-C) or high-fat control (HF-C) diet alone, or together with 15% of a unique mixture of FV (w/w, equivalent to 7–9 servings F&V/d for human) (LF-FV or HF-FV). The feeding will continue until 50% mortality is reached in one group. Body weight, body composition (using MRI), and blood T cell profile (using FACS) are monitored longitudinally at different time points. The results reported here are those assessed when mice were 7 months old. Results After 7 months of feeding, mice fed HF-C gained more weight compared to those fed LF-C. Mice fed HF-FV or LF-FV diets had significantly reduced weight gain and fat mass, and higher muscle mass compared to those fed HF-C or LF-C diet, respectively. Mice fed HF-C also had significantly lower percentage of blood CD3+, CD4+, and CD8 + T cells compared with the LF-C. FV supplementation prevented HFD-induced decrease in percentage of CD3+ and CD4+ cells. Furthermore, both % CD3+ and CD4+ cells were negatively correlated with body weight (P < 0.001) or percentage of fat mass (P < 0.001), and positively associated with percentage of lean mass (P < 0.001). Conclusions Our results suggest that consuming large amounts of a unique mixture of F&V curbs HFD-induced body weight gain, reduces fat mass, and favorably affects blood T cell population. Ongoing studies will assess these analytes when mice are 16 months old, and again when one group reaches 50% mortality, and determine their correlations with functional measures of T cell response, host resistance to infection, health span, and mortality. Funding Sources This study was supported by the U.S. Department of Agriculture – Agricultural Research Service (ARS), under Agreement No. 58–1950-4–004.


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