scholarly journals Linking the FTO obesity rs1421085 variant circuitry to cellular, metabolic, and organismal phenotypes in vivo

2021 ◽  
Vol 7 (30) ◽  
pp. eabg0108
Author(s):  
Samantha Laber ◽  
Sara Forcisi ◽  
Liz Bentley ◽  
Julia Petzold ◽  
Franco Moritz ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Species Conservation ◽  
Whole Body ◽  
Dependent Manner ◽  
Regulatory Module ◽  
Contextual Dependence ◽  
Fat Thickness ◽  
Cellular Phenotypes ◽  
Genetically Determined

Variants in FTO have the strongest association with obesity; however, it is still unclear how those noncoding variants mechanistically affect whole-body physiology. We engineered a deletion of the rs1421085 conserved cis-regulatory module (CRM) in mice and confirmed in vivo that the CRM modulates Irx3 and Irx5 gene expression and mitochondrial function in adipocytes. The CRM affects molecular and cellular phenotypes in an adipose depot–dependent manner and affects organismal phenotypes that are relevant for obesity, including decreased high-fat diet–induced weight gain, decreased whole-body fat mass, and decreased skin fat thickness. Last, we connected the CRM to a genetically determined effect on steroid patterns in males that was dependent on nutritional challenge and conserved across mice and humans. Together, our data establish cross-species conservation of the rs1421085 regulatory circuitry at the molecular, cellular, metabolic, and organismal level, revealing previously unknown contextual dependence of the variant’s action.

Effects of a high-fat diet and voluntary wheel running on gluconeogenesis and lipolysis in rats

1999 ◽  
Vol 86 (4) ◽  
pp. 1374-1380 ◽  
Author(s):  
Deborah A. Podolin ◽  
Yuren Wei ◽  
Michael J. Pagliassotti
Keyword(s):  
High Fat Diet ◽  
Corn Oil ◽  
Wheel Running ◽  
Whole Body ◽  
Free Access ◽  
Fat Pad ◽  
High Fat ◽  
Voluntary Wheel Running ◽  
Voluntary Wheel

The purpose of the present study was to determine the effects of diet composition and exercise on glycerol and glucose appearance rate (Ra) and on nonglycerol gluconeogenesis (Gneo) in vivo. Male Wistar rats were fed a high-starch diet (St, 68% of energy as cornstarch, 12% corn oil) for a 2-wk baseline period and then were randomly assigned to one of four experimental groups: St ( n = 7), high-fat (HF; 35% cornstarch, 45% corn oil; n = 8), St with free access to exercise wheels (StEx; n = 7), and HF with free access to exercise wheels (HFEx; n = 7). After 8 wk, glucose Rawhen using [3-3H]glucose, glycerol Rawhen using [2H5]glycerol (estimate of whole body lipolysis), and [3-13C]alanine incorporation into glucose (estimate of alanine Gneo) were determined. Body weight and fat pad mass were significantly ( P < 0.05) decreased in exercise vs. sedentary animals only. The average amount of exercise was not significantly different between StEx (3,212 ± 659 m/day) and HFEx (3,581 ± 765 m/day). The ratio of glucose to alanine enrichment and absolute glycerol Ra(μmol/min) were higher ( P < 0.05) in HF and HFEx compared with St and StEx rats. In separate experiments, the ratio of3H in C-2 to C-6 of glucose from3H2O (estimate of Gneo from pyruvate) was also higher ( P < 0.05) in HF ( n = 5) and HFEx ( n = 5), compared with St ( n = 5) and StEx ( n = 5) rats. Voluntary wheel running did not significantly increase estimated alanine or pyruvate Gneo or absolute glycerol Ra. Voluntary wheel running increased ( P< 0.05) glycerol Rawhen normalized to fat pad mass. These data suggest that a high-fat diet can increase in vivo Gneo from precursors that pass through pyruvate. They also suggest that changes in the absolute rate of glycerol Ramay contribute to the high-fat diet-induced increase in Gneo.

scholarly journals Cytochrome P-450 CYP2E1 knockout mice are protected against high-fat diet-induced obesity and insulin resistance

2012 ◽  
Vol 302 (5) ◽  
pp. E532-E539 ◽  
Author(s):  
Haihong Zong ◽  
Michal Armoni ◽  
Chava Harel ◽  
Eddy Karnieli ◽  
Jeffrey E. Pessin
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Knockout Mice ◽  
High Fat Diet ◽  
Whole Body ◽  
High Fat ◽  
Normal Chow ◽  
Glucose Output ◽  
Fat Diets

Conventional (whole body) CYP2E1 knockout mice displayed protection against high-fat diet-induced weight gain, obesity, and hyperlipidemia with increased energy expenditure despite normal food intake and spontaneous locomotor activity. In addition, the CYP2E1 knockout mice displayed a marked improvement in glucose tolerance on both normal chow and high-fat diets. Euglycemic-hyperinsulinemic clamps demonstrated a marked protection against high-fat diet-induced insulin resistance in CYP2E1 knockout mice, with enhanced adipose tissue glucose uptake and insulin suppression of hepatic glucose output. In parallel, adipose tissue was protected against high-fat diet-induced proinflammatory cytokine production. Taken together, these data demonstrate that the CYP2E1 deletion protects mice against high-fat diet-induced insulin resistance with improved glucose homeostasis in vivo.

scholarly journals Epiregulin induces leptin secretion and energy expenditure in high-fat diet-fed mice

2018 ◽  
Vol 239 (3) ◽  
pp. 377-388 ◽  
Author(s):  
Rumana Yasmeen ◽  
Qiwen Shen ◽  
Aejin Lee ◽  
Jacob H Leung ◽  
Devan Kowdley ◽  
...  
Keyword(s):  
Energy Expenditure ◽  
High Fat Diet ◽  
Ex Vivo ◽  
Mapk Pathway ◽  
Treated Group ◽  
Dependent Manner ◽  
High Fat ◽  
Fat Depots ◽  
Expression Of Genes

Adipokine leptin regulates neuroendocrine circuits that control energy expenditure, thermogenesis and weight loss. However, canonic regulators of leptin secretion, such as insulin and malonyl CoA, do not support these processes. We hypothesize that epiregulin (EREG), a growth factor that is secreted from fibroblasts under thermogenic and cachexia conditions, induces leptin secretion associated with energy dissipation. The effects of EREG on leptin secretion were studied ex vivo, in the intra-abdominal white adipose tissue (iAb WAT) explants, as well as in vivo, in WT mice with diet-induced obesity (DIO) and in ob/ob mice. These mice were pair fed a high-fat diet and treated with intraperitoneal injections of EREG. EREG increased leptin production and secretion in a dose-dependent manner in iAb fat explants via the EGFR/MAPK pathway. After 2 weeks, the plasma leptin concentration was increased by 215% in the EREG-treated group compared to the control DIO group. EREG-treated DIO mice had an increased metabolic rate and core temperature during the active dark cycle and displayed cold-induced thermogenesis. EREG treatment reduced iAb fat mass, the major site of leptin protein production and secretion, but did not reduce the mass of the other fat depots. In the iAb fat, expression of genes supporting mitochondrial oxidation and thermogenesis was increased in EREG-treated mice vs control DIO mice. All metabolic and gene regulation effects of EREG treatment were abolished in leptin-deficient ob/ob mice. Our data revealed a new role of EREG in induction of leptin secretion leading to the energy expenditure state. EREG could be a potential target protein to regulate hypo- and hyperleptinemia, underlying metabolic and immune diseases.

scholarly journals Downregulation of RelA (p65) by Rapamycin Inhibits Murine Adipocyte Differentiation and Reduces Fat Mass of C57BL/6J Mice despite High Fat Diet

ISRN Obesity ◽  
2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Peter D. Ray ◽  
Reid A. Maclellan ◽  
Jin He ◽  
Zhigang Liu ◽  
Jianguo Wu
Keyword(s):  
Body Weight ◽  
High Fat Diet ◽  
Adipocyte Differentiation ◽  
Mammalian Target Of Rapamycin ◽  
Subcutaneous Fat ◽  
Immunosuppressive Agent ◽  
Dependent Manner ◽  
High Fat

Rapamycin (RAPA) is a clinical immunosuppressive agent first reported in the literature in 1975 after its discovery in a soil sample from the island of Rapa Nui. Aside from the well-documented effects of RAPA on cell division and immunologic response, the literature reveals it to have negative effects on adipocyte and osteocyte differentiation as well. Understanding of the molecular effects of RAPA on cell differentiation is fragmentary in regard to these cell lineages. In this paper, we examined a potential mechanism for RAPA’s effects on adipocyte differentiation in vitro and in vivo. The data point to a unique role of Rel A (p65)—a component of the NF-κB system—in mediating this event. In murine adipose derived stem cell cultures (muADSCs) from C57BL/6J mice, RAPA was found to selectively downregulate RelA/p65, mammalian target of rapamycin (mTOR), and do so in a dose-dependent manner. This implies a novel role for RelA in adipocyte biology. Intracellular lipid accumulation—as subjectively observed—was also decreased in muADSCs treated with RAPA. Mice treated with RAPA had reduced overall body weight and reduced size of both intraabdominal and subcutaneous fat pads. When treated with RAPA, mice fed a high fat diet did not develop obesity and were not different from their regular diet controls in terms of body weight. These results suggested that RAPA inhibits adipogenesis and lipogenesis of muADSCs resulting in a prevention of obesity in C57BL/6J mice. This inhibition is strong enough to negate the effects of a high fat diet and seems to act by downregulating the RelA/p65 mTOR signaling pathway—a key component of the NF-κB family.

scholarly journals Adipocyte Utx Deficiency Promotes High-Fat Diet-Induced Metabolic Dysfunction in Mice

Cells ◽  
2022 ◽  
Vol 11 (2) ◽  
pp. 181
Author(s):  
Fenfen Li ◽  
Shirong Wang ◽  
Xin Cui ◽  
Jia Jing ◽  
Liqing Yu ◽  
...  
Keyword(s):  
Adipose Tissue ◽  
High Fat Diet ◽  
Whole Body ◽  
Brown Adipocyte ◽  
Chow Diet ◽  
Main Function ◽  
Metabolic Dysfunction ◽  
High Fat ◽  
Brown Adipose

While the main function of white adipose tissue (WAT) is to store surplus of energy as triacylglycerol, that of brown adipose tissue (BAT) is to burn energy as heat. Epigenetic mechanisms participate prominently in both WAT and BAT energy metabolism. We previously reported that the histone demethylase ubiquitously transcribed tetratricopeptide (Utx) is a positive regulator of brown adipocyte thermogenesis. Here, we aimed to investigate whether Utx also regulates WAT metabolism in vivo. We generated a mouse model with Utx deficiency in adipocytes (AUTXKO). AUTXKO animals fed a chow diet had higher body weight, more fat mass and impaired glucose tolerance. AUTXKO mice also exhibited cold intolerance with an impaired brown fat thermogenic program. When challenged with high-fat diet (HFD), AUTXKO mice displayed adipose dysfunction featured by suppressed lipogenic pathways, exacerbated inflammation and fibrosis with less fat storage in adipose tissues and more lipid storage in the liver; as a result, AUTXKO mice showed a disturbance in whole body glucose homeostasis and hepatic steatosis. Our data demonstrate that Utx deficiency in adipocytes limits adipose tissue expansion under HFD challenge and induces metabolic dysfunction via adipose tissue remodeling. We conclude that adipocyte Utx is a key regulator of systemic metabolic homeostasis.

Tissue distribution of tetrabromobisphenol A and cadmium in mixture inhalation exposure

2019 ◽  
Vol 35 (2) ◽  
pp. 165-176 ◽  
Author(s):  
Jiangfei Chen ◽  
Duan Kang ◽  
Zhi Yan ◽  
Qiaosen Shen ◽  
Yanqi Lou ◽  
...  
Keyword(s):  
Flame Retardants ◽  
Inhalation Exposure ◽  
Exposure Period ◽  
Waste Recycling ◽  
Whole Body ◽  
Tetrabromobisphenol A ◽  
Dependent Manner ◽  
Tissue Samples ◽  
Liver And Kidney

Tetrabromobisphenol A (TBBPA) and cadmium chloride (CdCl2) are the typical representative pollutants of brominated flame retardants and heavy metals found in the air of e-waste recycling workshops. However, their metabolic kinetics through mixture inhalation is unknown. In the present study, 8-week old Institute of Cancer Research (ICR) male mice were whole-body exposed to TBBPA and CdCl2 mixtures by inhalation. Tissue samples were collected for TBBPA and cadmium (Cd) analysis at 2, 4, 6, and 8 weeks during exposure and at 4 and 8 weeks after the completion of the 8-week exposure period. TBBPA was mainly distributed to the lungs, liver, kidney, testis, and spleen, with a high amount accumulated in the brain, liver, and spleen. Cd was mainly distributed to the lungs, liver, and kidney, with a high amount accumulated in the liver, kidney, and testis and a low amount accumulated in brain and serum. Tissue burden of TBBPA and Cd in all organs increased in a dose- and time-dependent manner during the exposure period. However, 4 weeks after the completion of an 8-week exposure, TBBPA concentrations in the liver, testis, brain, and serum and Cd concentrations in the liver, testis, and kidney were higher than the corresponding tissue concentrations during the exposure period. The rapid accumulation of both TBBPA and Cd in the lungs after inhalation exposure indicated a high risk of the respiratory system diseases for workers in e-waste recycling workshops. In addition, the migration of both TBBPA and Cd from lungs to liver and testis may result in more complex toxic effects in vivo.

Primary infection of mice with high titer inoculum respiratory syncytial virus: characterization and response to antiviral therapy

2005 ◽  
Vol 83 (2) ◽  
pp. 198-213 ◽  
Author(s):  
Gordon Bolger ◽  
Nicole Lapeyre ◽  
Nathalie Dansereau ◽  
Lisette Lagacé ◽  
Gerald Berry ◽  
...  
Keyword(s):  
Respiratory Syncytial Virus ◽  
Antiviral Therapy ◽  
Virus Disease ◽  
High Titer ◽  
Lavage Fluid ◽  
Whole Body ◽  
Dependent Manner ◽  
Syncytial Virus ◽  
Dose Dependent

Intranasal infection of BALB/c mice with respiratory syncytial virus (RSV)-A2 (0.5 × 108– 2.0 × 108plaque-forming units, PFU) produced disease characterized by weight loss (2–3 g) and mortality (60%–100%) with the mean day of death ranging from 6–7 d after infection. The extent of RSV disease was inoculum titer-dependent and required a replication competent virus. Lung titers of virus peaked at 0.5-1 × 106PFU/g wet weight. Bronchoalveolar lavage fluid (BALF) levels of IL-1β, TNF-α, INF-γ IL-12, IL-6, MIP-1α, RANTES, and protein were elevated, whereas IL-2, IL-4, IL-5, IL-13, and IL-10 were unchanged. Histological assessment of lungs revealed marked inflammatory pathology characterized by bronchiolitis, vasculitis, and interstitial pneumonia. Whole-body plethysmography revealed significant disease-associated deficits of respiratory function. Therapy with ribavirin administered either by the intranasal, subcutaneous, or oral route significantly reduced disease in a dose-dependent manner. Delaying the initiation of therapy resulted in a loss of activity for ribavirin. Synagis®administered either intramuscularly as a single dose in prophylaxis or intranasally in prophylaxis, followed by therapy, also significantly reduced disease in a dose-dependent manner. Infection of mice with a high titer inoculum of RSV-A2 resulted in severe and fatal pulmonary disease that was responsive to treatment. This model may be useful to characterize the in vivo activity of experimental therapies for RSV infection.Key words: respiratory syncytial virus, disease, mortality, antiviral therapy.

Neural control of breathing: insights from genetic mouse models

2008 ◽  
Vol 104 (5) ◽  
pp. 1522-1530 ◽  
Author(s):  
C. Gaultier ◽  
J Gallego
Keyword(s):  
Mouse Models ◽  
Neural Control ◽  
Respiratory Control ◽  
Whole Body ◽  
Neuron Network ◽  
Newborn Mice ◽  
Hypoventilation Syndrome ◽  
New Treatments ◽  
Genetically Determined

Recent studies described the in vivo ventilatory phenotype of mutant newborn mice with targeted deletions of genes involved in the organization and development of the respiratory-neuron network. Whole body flow barometric plethysmography is the noninvasive method of choice for studying unrestrained newborn mice. Breathing-pattern abnormalities with apneas occur in mutant newborn mice that lack genes involved in the development and modulation of rhythmogenesis. Studies of deficits in ventilatory responses to hypercapnia and/or hypoxia helped to identify genes involved in chemosensitivity to oxygen and carbon dioxide. Combined studies in mutant newborn mice and in humans have shed light on the pathogenesis of genetically determined respiratory-control abnormalities such as congenital central hypoventilation syndrome, Rett syndrome, and Prader-Willi syndrome. The development of mouse models has opened up the field of research into new treatments for respiratory-control disorders in humans.

scholarly journals REC-2006—A Fractionated Extract ofPodophyllum hexandrumProtects Cellular DNA from Radiation-Induced Damage by Reducing the Initial Damage and Enhancing Its RepairIn Vivo

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Pankaj Chaudhary ◽  
Sandeep Kumar Shukla ◽  
Rakesh Kumar Sharma
Keyword(s):  
Dna Damage ◽  
Free Radicals ◽  
Viral Infections ◽  
Quantitative Polymerase Chain Reaction ◽  
Globin Gene ◽  
Whole Body ◽  
Perennial Herb ◽  
Dependent Manner ◽  
Radiation Induced

Podophyllum hexandrum, a perennial herb commonly known as the Himalayan May Apple, is well known in Indian and Chinese traditional systems of medicine.P. hexandrumhas been widely used for the treatment of venereal warts, skin infections, bacterial and viral infections, and different cancers of the brain, lung and bladder. This study aimed at elucidating the effect of REC-2006, a bioactive fractionated extract from the rhizome ofP. hexandrum, on the kinetics of induction and repair of radiation-induced DNA damage in murine thymocytesin vivo. We evaluated its effect on non-specific radiation-induced DNA damage by the alkaline halo assay in terms of relative nuclear spreading factor (RNSF) and gene-specific radiation-induced DNA damage via semi-quantitative polymerase chain reaction. Whole body exposure of animals with gamma rays (10 Gy) caused a significant amount of DNA damage in thymocytes (RNSF values 17.7 ± 0.47, 12.96 ± 1.64 and 3.3 ± 0.014) and a reduction in the amplification ofβ-globin gene to 0, 28 and 43% at 0, 15 and 60 min, respectively. Administrating REC-2006 at a radioprotective concentration (15 mg kg−1body weight) 1 h before irradiation resulted in time-dependent reduction of DNA damage evident as a decrease in RNSF values 6.156 ± 0.576, 1.647 ± 0.534 and 0.496 ± 0.012, and an increase inβ-globin gene amplification 36, 95 and 99%, at 0, 15 and 60 min, respectively. REC-2006 scavenged radiation-induced hydroxyl radicals in a dose-dependent manner stabilized DPPH free radicals and also inhibited superoxide anions. Various polyphenols and flavonoides present in REC-2006 might contribute to scavenging of radiation-induced free radicals, thereby preventing DNA damage and stimulating its repair.

scholarly journals In Vitro and In Vivo Antioxidative Activity against Radiation-Induced Damage and the Systematic Chemical Components of Different Extracts of Lagotis brevituba Maxim

2020 ◽  
Vol 2020 ◽  
pp. 1-14
Author(s):  
Dan Zhang ◽  
Lihong Tan ◽  
Ling Yao ◽  
Wei Tao ◽  
Ruixue Gong ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Antioxidant Activities ◽  
Whole Body ◽  
Chemical Components ◽  
Control Group ◽  
Dependent Manner ◽  
Antioxidant Assays ◽  
Radiation Induced

Lagotis brevituba Maxim is a perennial species distributed in the highlands of China, which has been used for more than 2000 years as a traditional Tibetan medicinal plant. However, no attention has been paid to the antioxidant activities of Lagotis brevituba Maxim in vitro or in vivo. Thus, this study aimed to evaluate the in vitro and in vivo antioxidant activity of Lagotis brevituba Maxim against radiation-induced damage as well as the systematic chemical components. To explore the relationship between the antioxidant activity and extraction solvent, Lagotis brevituba Maxim was extracted with three different solvents: methanol, water, and acetone. In antioxidant assays in vitro, the water extract had the strongest reducing power, 2,2-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity compared with the methanol and acetone extracts. However, the methanol extract was more potent in the β-carotene/linoleic acid cooxidation assay. In antioxidant assays in vivo, mice that were exposed to 6.0 Gy60Co γ-ray whole-body radiation on day 15 after administration of Lagotis brevituba Maxim decreased their level of malondialdehyde (MDA) in a dose-dependent manner compared with the control group, indicating that Lagotis brevituba Maxim had favorable antioxidant activities in vivo. In addition, a total of 44 compounds were tentatively identified by liquid chromatography electrospray ionization quadrupole time-of-flight mass spectrometry (LC-ESI-QTOF-MS/MS), including 19 flavonoids, 14 phenols, 8 phenylethanoid glycosides, 2 iridoid glycosides, and 1 carbohydrate. We obtained 25 compounds from plants in the genus Lagotis for the first time. These results suggested that Lagotis brevituba Maxim had potent antioxidant activity and could be explored as a novel natural antioxidant.

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