Leptin receptor-deficient obese Zucker rats reduce their food intake in response to hypobaric hypoxia

2006 ◽  
Vol 290 (3) ◽  
pp. E591-E597 ◽  
Author(s):  
Nadine Simler ◽  
Alexandra Grosfeld ◽  
André Peinnequin ◽  
Michèle Guerre-Millo ◽  
André-Xavier Bigard
Keyword(s):  
Gene Expression ◽  
Body Weight ◽  
Adipose Tissue ◽  
Food Intake ◽  
Hypobaric Hypoxia ◽  
Leptin Receptor ◽  
Zucker Rats ◽  
Hypoxia Exposure ◽  
Obese Rats ◽  
Hypothalamic Neuropeptides

Exposure to hypoxia induces anorexia in humans and rodents, but the role of leptin remains under discussion and that of orexigenic and anorexigenic hypothalamic neuropeptides remains unknown. The present study was designed to address this issue by using obese (Leprfa/Leprfa) Zucker rats, a rat model of genetic leptin receptor deficiency. Homozygous lean (LeprFA/LeprFA) and obese (Leprfa/Leprfa) rats were randomly assigned to two groups, either kept at ambient pressure or exposed to hypobaric hypoxia for 1, 2, or 4 days (barometric pressure, 505 hPa). Food intake and body weight were recorded throughout the experiment. The expression of leptin and vascular endothelial growth factor (VEGF) genes was studied in adipose tissue with real-time quantitative PCR and that of selected orexigenic and anorexigenic neuropeptides was measured in the hypothalamus. Lean and obese rats exhibited a similar hypophagia (38 and 67% of initial values at day 1, respectively, P < 0.01) and initial decrease in body weight during hypoxia exposure. Hypoxia led to increased plasma leptin levels only in obese rats. This resulted from increased leptin gene expression in adipose tissue in response to hypoxia, in association with enhanced VEGF gene expression. Increased hypothalamic neuropeptide Y levels in lean rats 2 days after hypoxia exposure contributed to accounting for the enhanced food consumption. No significant changes occurred in the expression of other hypothalamic neuropeptides involved in the control of food intake. This study demonstrates unequivocally that altitude-induced anorexia cannot be ascribed to anorectic signals triggered by enhanced leptin production or alterations of hypothalamic neuropeptides involved in anabolic or catabolic pathways.

scholarly journals Adipose-tissue-specific increase in glyceraldehyde-3-phosphate dehydrogenase activity and mRNA amounts in suckling pre-obese Zucker rats. Effect of weaning

1988 ◽  
Vol 254 (2) ◽  
pp. 483-487 ◽  
Author(s):  
I Dugail ◽  
A Quignard-Boulange ◽  
R Bazin ◽  
X Le Liepvre ◽  
M Lavau
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Zucker Rats ◽  
Tissue Specific ◽  
Gapdh Gene ◽  
Gapdh Activity ◽  
Weanling Rats ◽  
Obese Rats ◽  
Specific Increase ◽  
Obese Zucker Rats

The regulation of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) gene expression was studied during the onset of obesity in the genetically obese (fa/fa) rat by determination of GAPDH activity and hybridizable mRNA amounts in adipose tissue and liver from suckling and weanling rats. GADPH activity remained low throughout the suckling period, and a burst of activity occurred after weaning in both lean and obese pups. As early as 7 days of age, adipose tissue from pre-obese rats displayed a significant increase in enzyme activity, whereas no difference could be detected in the liver. In both suckling (16 days of age) and weanling (30 days of age) obese rats a proportionate increase in GAPDH activity and mRNA amounts was observed in adipose tissue, but not in liver. It is concluded that the obese genotype influences GAPDH gene expression at a pretranslational level and in a tissue-specific manner. This phenomenon could partly contribute to the hyperactive fat accretion in the obese rat, since glycolysis is the major metabolic pathway for lipogenic substrates in adipose tissue.

scholarly journals A Lipophilic Fucoxanthin-Rich Phaeodactylum tricornutum Extract Ameliorates Effects of Diet-Induced Obesity in C57BL/6J Mice

Nutrients ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 796 ◽  
Author(s):  
Andrea Gille ◽  
Bojan Stojnic ◽  
Felix Derwenskus ◽  
Andreas Trautmann ◽  
Ulrike Schmid-Staiger ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Weight ◽  
Adipose Tissue ◽  
Food Intake ◽  
Phaeodactylum Tricornutum ◽  
Body Weight Gain ◽  
Acid Oxidation ◽  
Lipid Uptake ◽  
Interscapular Brown Adipose Tissue ◽  
Brown Adipose

Phaeodactylum tricornutum (P. tricornutum) comprise several lipophilic constituents with proposed anti-obesity and anti-diabetic properties. We investigated the effect of an ethanolic P. tricornutum extract (PTE) on energy metabolism in obesity-prone mice fed a high fat diet (HFD). Six- to eight-week-old male C57BL/6J mice were switched to HFD and, at the same time, received orally placebo or PTE (100 mg or 300 mg/kg body weight/day). Body weight, body composition, and food intake were monitored. After 26 days, blood and tissue samples were collected for biochemical, morphological, and gene expression analyses. PTE-supplemented mice accumulated fucoxanthin metabolites in adipose tissues and attained lower body weight gain, body fat content, weight of white adipose tissue (WAT) depots, and inguinal WAT adipocyte size than controls, independent of decreased food intake. PTE supplementation was associated with lower expression of Mest (a marker of fat tissue expandability) in WAT depots, lower gene expression related to lipid uptake and turnover in visceral WAT, increased expression of genes key to fatty acid oxidation and thermogenesis (Cpt1, Ucp1) in subcutaneous WAT, and signs of thermogenic activation including enhanced UCP1 protein in interscapular brown adipose tissue. In conclusion, these data show the potential of PTE to ameliorate HFD-induced obesity in vivo.

scholarly journals Characterization of the inflammatory and metabolic profile of adipose tissue in a mouse model of chronic hypoxia

2013 ◽  
Vol 114 (11) ◽  
pp. 1619-1628 ◽  
Author(s):  
Bram van den Borst ◽  
Annemie M. W. J. Schols ◽  
Chiel de Theije ◽  
Agnes W. Boots ◽  
S. Eleonore Köhler ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Weight ◽  
Adipose Tissue ◽  
Food Intake ◽  
Metabolic Profile ◽  
Chronic Hypoxia ◽  
Chronic Obstructive ◽  
Adipocyte Size ◽  
Metabolic Complications ◽  
Macrophage Density

In both obesity and chronic obstructive pulmonary disease (COPD), altered oxygen tension in adipose tissue (AT) has been suggested to evoke AT dysfunction, subsequently contributing to metabolic complications. Studying the effects of chronic hypoxia on AT function will add to our understanding of the complex pathophysiology of alterations in AT inflammation, metabolism, and mass observed in both obesity and COPD. This study investigated the inflammatory and metabolic profile of AT after chronic hypoxia. Fifty-two-week-old C57Bl/6J mice were exposed to chronic hypoxia (8% O2) or normoxia for 21 days, after which AT and plasma were collected. Adipocyte size, AT gene expression of inflammatory and metabolic genes, AT macrophage density, and circulating adipokine concentrations were measured. Food intake and body weight decreased upon initiation of hypoxia. However, whereas food intake normalized after 10 days, lower body weight persisted. Chronic hypoxia markedly reduced AT mass and adipocyte size. AT macrophage density and expression of Emr1, Ccl2, Lep, and Tnf were decreased, whereas Serpine1 and Adipoq expression levels were increased after chronic hypoxia. Concomitantly, chronic hypoxia increased AT expression of regulators of oxidative metabolism and markers of mitochondrial function and lipolysis. Circulating IL-6 and PAI-1 concentrations were increased, and leptin concentration was decreased after chronic hypoxia. Chronic hypoxia is associated with decreased rather than increased AT inflammation, and markedly decreased fat mass and adipocyte size. Furthermore, our data indicate that chronic hypoxia is accompanied by significant alterations in AT metabolic gene expression, pointing toward an enhanced AT metabolic rate.

scholarly journals Intact Leptin Receptor Signalling is not Required for the Sustained Weight Loss and Appetite Suppression Induced by Roux-en-Y Gastric Bypass Surgery

2021 ◽  
Author(s):  
Mohammed K. Hankir ◽  
Laura Rotzinger ◽  
Arno Nordbeck ◽  
Caroline Corteville ◽  
Annett Hoffmann ◽  
...  
Keyword(s):  
Weight Loss ◽  
Gastric Bypass ◽  
Body Weight ◽  
Food Intake ◽  
Glucose Tolerance ◽  
Leptin Receptor ◽  
Oral Glucose ◽  
Oral Glucose Tolerance ◽  
Sustained Weight Loss ◽  
Obese Rats

Leptin is the archetypal adipokine that promotes a negative whole-body energy balance largely through its action on brain leptin receptors. As such, the sustained weight loss and food intake suppression induced by Roux-en-Y gastric bypass (RYGB) surgery have been attributed to enhancement of endogenous leptin action. We formally revisited this idea in Zucker Fatty fa/fa rats, an established genetic model of leptin receptor deficiency, and carefully compared their body weight, food intake and oral glucose tolerance after RYGB with that of sham-operated fa/fa (obese) and sham-operated fa/+ (lean) rats. We found that RYGB rats sustainably lost body weight, which converged with that of lean rats and was 25.5 % lower than that of obese rats by the end of the 4 week study period. Correspondingly, daily food intake of RYGB rats was similar to that of lean rats from the second postoperative week, while it was always at least 33.9 % lower than that of obese rats. Further, oral glucose tolerance of RYGB rats was normalized at the forth postoperative week. These findings assert that leptin is not an essential mediator of the sustained weight loss and food intake suppression as well as the improved glycemic control induced by RYGB, and instead point to additional circulating and/or neural factors.

Subdiaphragmatic vagal deafferentation affects body weight gain and glucose metabolism in obese male Zucker (fa/fa) rats

2005 ◽  
Vol 289 (4) ◽  
pp. R1027-R1034 ◽  
Author(s):  
Bettina Ferrari ◽  
Myrtha Arnold ◽  
Richard D. Carr ◽  
Wolfgang Langhans ◽  
Giovanni Pacini ◽  
...  
Keyword(s):  
Body Weight ◽  
Weight Gain ◽  
Insulin Sensitivity ◽  
Food Intake ◽  
Plasma Glucose ◽  
Body Weight Gain ◽  
Zucker Rats ◽  
Sensitivity Index ◽  
Insulin Sensitivity Index ◽  
Obese Rats

We investigated the effect of subdiaphragmatic vagal deafferentation (SDA) on food intake, body weight gain, and metabolism in obese ( fa/ fa) and lean ( Fa/?) Zucker rats. Before and after recovery from surgery, food intake and body weight gain were recorded, and plasma glucose and insulin were measured in tail-prick blood samples. After implantation of a jugular vein catheter, an intravenous glucose tolerance test (IVGTT) was performed, followed by minimal modeling to estimate the insulin sensitivity index. Food intake relative to metabolic body weight (g/kg0.75) and daily body weight gain after surgery were lower ( P < 0.05) in SDA than in sham obese but not lean rats. Before surgery, plasma glucose and insulin concentrations were lower ( P < 0.05) in lean than in obese rats but did not differ between surgical groups within both genotypes. Four weeks after surgery, plasma glucose and insulin were still similar in SDA and sham lean rats but lower ( P < 0.05) in SDA than in sham obese rats. IVGTT revealed a downward shift of the plasma insulin profile by SDA in obese but not lean rats, whereas the plasma glucose profile was unaffected. SDA decreased ( P < 0.05) area under the curve for insulin but not glucose in obese rats. The insulin sensitivity index was higher in lean than in obese rats but was not affected by SDA in both genotypes. These results suggest that elimination of vagal afferent signals from the upper gut reduces food intake and body weight gain without affecting the insulin sensitivity index measured by minimal modeling in obese Zucker rats.

scholarly journals Chemerin impairs food intake and body weight in chicken: Focus on hypothalamic neuropeptides gene expression and AMPK signaling pathway

2021 ◽  
Vol 304 ◽  
pp. 113721
Author(s):  
Anthony Estienne ◽  
Christelle Ramé ◽  
Patrice Ganier ◽  
Marine Chahnamian ◽  
Alix Barbe ◽  
...  
Keyword(s):  
Gene Expression ◽  
Body Weight ◽  
Food Intake ◽  
Signaling Pathway ◽  
Ampk Signaling ◽  
Hypothalamic Neuropeptides

scholarly journals The effects of corticosterone, cold exposure and overfeeding with sucrose on brown adipose tissue of obese Zucker rats (fa/fa)

1983 ◽  
Vol 214 (1) ◽  
pp. 215-223 ◽  
Author(s):  
S Holt ◽  
D A York ◽  
J T R Fitzsimons
Keyword(s):  
Adipose Tissue ◽  
Food Intake ◽  
Brown Adipose Tissue ◽  
Cold Exposure ◽  
Zucker Rats ◽  
Brown Adipose ◽  
Obese Rats ◽  
Brown Adipose Tissue Thermogenesis ◽  
Obese Zucker Rats ◽  
Normal Increase

GDP binding to brown-adipose-tissue mitochondria was decreased in obese Zucker rats. Adrenalectomy restored both GDP binding and serum tri-iodothyronine of obese rats to values observed in lean rats. The effects of adrenalectomy on GDP binding and serum tri-iodothyronine were reversed by corticosterone. Decreasing food intake had no effect on brown-adipose-tissue GDP binding in obese rats. Young (5-week-old) obese rats showed a normal increase in brown-adipose-tissue mitochondrial GDP binding after housing at 4 degrees C for 7 days, but this response was attenuated in 10-week-old obese rats. Overfeeding with sucrose increased brown-adipose-tissue thermogenesis in lean, but not in obese, rats. After adrenalectomy, overfeeding with sucrose enhanced brown-adipose-tissue mitochondrial GDP binding in obese rats.

scholarly journals High Intakes of [6S]-5-Methyltetrahydrofolic Acid Compared with Folic Acid during Pregnancy Programs Central and Peripheral Mechanisms Favouring Increased Food Intake and Body Weight of Mature Female Offspring

Nutrients ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1477
Author(s):  
Emanuela Pannia ◽  
Rola Hammoud ◽  
Ruslan Kubant ◽  
Jong Yup Sa ◽  
Rebecca Simonian ◽  
...  
Keyword(s):  
Body Weight ◽  
Folic Acid ◽  
Food Intake ◽  
Leptin Receptor ◽  
Liver Weight ◽  
Female Offspring ◽  
Mature Female ◽  
Cytokine Signaling ◽  
Light Cycle ◽  
Energy Regulation

Supplementation with [6S]-5-methyltetrahydrofolic acid (MTHF) is recommended as an alternative to folic acid (FA) in prenatal supplements. This study compared equimolar gestational FA and MTHF diets on energy regulation of female offspring. Wistar rats were fed an AIN-93G diet with recommended (2 mg/kg diet) or 5-fold (5X) intakes of MTHF or FA. At weaning, female offspring were fed a 45% fat diet until 19 weeks. The 5X-MTHF offspring had higher body weight (>15%), food intake (8%), light-cycle energy expenditure, and lower activity compared to 5X-FA offspring (p < 0.05). Both the 5X offspring had higher plasma levels of the anorectic hormone leptin at birth (60%) and at 19 weeks (40%), and lower liver weight and total liver lipids compared to the 1X offspring (p < 0.05). Hypothalamic mRNA expression of leptin receptor (ObRb) was lower, and of suppressor of cytokine signaling-3 (Socs3) was higher in the 5X-MTHF offspring (p < 0.05), suggesting central leptin dysregulation. In contrast, the 5X-FA offspring had higher expression of genes encoding for dopamine and GABA- neurotransmitter receptors (p < 0.01), consistent with their phenotype and reduced food intake. When fed folate diets at the requirement level, no differences were found due to form in the offspring. We conclude that MTHF compared to FA consumed at high levels in the gestational diets program central and peripheral mechanisms to favour increased weight gain in the offspring. These pre-clinical findings caution against high gestational intakes of folates of either form and encourage clinical trials examining their long-term health effects when consumed during pregnancy.

Sign in / Sign up

Export Citation Format

Share Document