Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Metabolic adaptation of white adipose tissue to acute, short-term environmental oxygen restriction in mice

ABSTRACT: White adipose tissue (WAT) expansion during e.g. obesity reduces oxygen availability in WAT in mice. Little is known on the adaptation of WAT to mild environmental oxygen restriction (OxR). Therefore, we studied metabolic adaptation to acute OxR in fasted, diet-induced moderately obese mice that were exposed to mild hypoxic (12% O2) or normoxic (20.9% O2) conditions for only 6 hours. Adaptation was assessed by determination of amino acids and (acyl)carnitines levels in serum and WAT, and by whole genome expression analysis in WAT. Adaptation was also assessed during the exposure using indirect calorimetry. We found that OxR reduced mitochondrial oxidation at whole-body level, as shown by a reduction in whole-body oxygen consumption and an increase in serum long-chain acylcarnitine levels. WAT did not seem to contribute to this serum profile since only short-chain acylcarnitines were increased in WAT and gene expression analysis indicated an increase in mitochondrial oxidation, based on coordinate down-regulation of Sirt4, Gpam and Chchd3/Minos3. In addition, OxR did not induce oxidative stress in obese WAT, but increased molecular pathways involved in cell growth and proliferation. OxR increased levels of tyrosine, lysine and ornithine in serum and of leucine/isoleucine in WAT. This study shows that OxR limits oxidative phosphorylation at whole-body level, but in WAT compensatory mechanisms seem to operate. The down-regulation of the mitochondria-related genes Sirt4, Gpam, and Chchd3 may be considered as a biomarker profile for WAT mitochondrial reprogramming in response to acute exposure to limited oxygen availability.

ORGANISM(S): Mus musculus

PROVIDER: GSE64238 | GEO | 2020/09/21

REPOSITORIES: GEO

ACCESS DATA

Json Xml

Similar Datasets

Hypoxia-induced metabolic dysfunction in WAT

Project description:Background: Excessive white adipose tissue (WAT) expansion as in obesity is generally associated with chronic inflammation of WAT, which contributes to obesity associated complications. Low oxygen availability in WAT is hypothesized to be the initiator of this inflammatory response. Hypothesis: We examined the hypothesis that local tissue hypoxia is responsible for the initiation of inflammation in WAT. Research design and methods: Diet-induced obese male C57BL/6JOlaHsd mice, housed at thermoneutrality, were exposed to mild environmental oxygen restriction (OxR, to 13% oxygen) for five days and compared with mice kept at normoxia, after which WAT and serum were collected. Body composition, systemic metabolic parameters, WAT macrophage infiltration (as marker for tissue inflammation) and whole genome microarray analysis, and circulating adipokines were measured. Results: Five days OxR decreased body weight and fat mass, and increased blood levels of haemoglobin and haematocrit, as well as lactate to glucose ratio, which indicated systemic hypoxia. No difference in adipose tissue inflammation was found, which was supported by down regulation of inflammation-associated transcript levels of S100a8, Saa1, and Saa3. Serum metabolomics revealed an increase of branched chain amino acid Valine and propionylcarnitine. Adipokines CCDC3, CCK, and Adiponectin are reduced by OxR on transcript (Cck) or serum protein level (Adiponectin), or both (CCDC3). Conclusions: Mild oxygen restriction does not increase white adipose tissue inflammation in obese mice. However, a systemic adaptation together with a metabolic response in WAT was observed.

2019-06-24 | GSE53802 | GEO

High-fat dietary restriction in mice induces substrate efficiency and improves metabolic health

Project description:High energy intake and, specifically, high dietary fat intake challenges the mammalian metabolism and correlates with many metabolic disorders, such as obesity and diabetes. Dietary restriction (DR) is, on the other hand, known to prevent the development of metabolic disorders. The current Western diets are highly enriched in fat and it is as yet unclear whether DR on a certain high-fat (HF) diet elicits similar beneficial effects on health. Here, we report that HF-DR improves metabolic health of mice, compared to mice receiving the same diet on an ad-libitum basis (HF-AL). Already after five weeks of restriction the serum levels of cholesterol and leptin were significantly decreased in HF-DR mice, while their glucose sensitivity and serum adiponectin levels were increased. The body weight and measured serum parameters remained stable in the following 7 weeks of restriction, implying metabolic adaptation. To understand the molecular events associated with this adaptation, we analysed gene expression in white adipose tissue (WAT) with whole genome microarrays. HF-DR strongly influenced gene expression in WAT; in total 8,643 genes were differentially expressed between both groups of mice, with a major role for genes involved in lipid metabolism and mitochondrial functioning. This was confirmed by qRT-PCR and substantiated by an increase in mitochondrial density in WAT of HF-DR mice. These results provide new insights in the metabolic flexibility of dietary restricted animals and suggest the development of substrate efficiency. Limiting food intake by decreasing portion sizes, while maintaining energy sufficiency, may similarly benefit metabolic health in humans.

2011-08-24 | GSE27213 | GEO

SIRT4 KO livers microarray

Project description:Sirtuins are a family of protein deacetylases, deacylases, and ADP-ribosyltransferases that regulate life span, control the onset of numerous age-associated diseases, and mediate metabolic homeostasis. We have uncovered a novel role for the mitochondrial sirtuin SIRT4 in the regulation of hepatic lipid metabolism during changes in nutrient availability. We show that SIRT4 levels decrease in the liver during fasting and that SIRT4 null mice display increased expression of hepatic peroxisome proliferator activated receptor (PPAR ) target genes associated with fatty acid catabolism. Accordingly, primary hepatocytes from SIRT4 knockout (KO) mice exhibit higher rates of fatty acid oxidation than wild-type hepatocytes, and SIRT4 overexpression decreases fatty acid oxidation rates. The enhanced fatty acid oxidation observed in SIRT4 KO hepatocytes requires functional SIRT1, demonstrating a clear cross talk between mitochondrial and nuclear sirtuins. Thus, SIRT4 is a new component of mitochondrial signaling in the liver and functions as an important regulator of lipid metabolism. SIRT4 knockout (KO) and wild-type (WT) littermates (male; n 6 per genotype; 7- to 8-month-old littermates) were sacrificed after a 16-h overnight fast. Samples were individually hybridized on Affymetrix Mouse Genome 430 2.0 GeneChips by the Biopolymers Facility (Harvard Medical School).

2014-03-28 | E-GEOD-56321 | biostudies-arrayexpress

SIRT4 KO livers microarray

2014-03-28 | GSE56321 | GEO

Downregulation of miR-15b is associated with increased SIRT4 expression in premature senescence and photoaging of the skin

Project description:Sirtuins are deacetylases or ADP-ribosyltransferases which are implicated in multiple pathways involved in metabolism and life-span regulation. Here, we link the mitochondrial sirtuin SIRT4, which overexpression negatively impacts on mitochondrial oxidative capacity, with premature senescence and skin aging. Accordingly, SIRT4 mRNA levels were significantly increased in vitro in human dermal fibroblasts after repetitive UVB exposure or in senescence triggered by mitotic spindle stress or ionizing radiation. Similarly, analysis of SIRT4 expression in vivo in human skin revealed upregulation of SIRT4 mRNA levels in the dermal compartment of photaged skin as compared with the dermis of intrinsically aged skin. In all our in vitro models, upregulation of SIRT4 expression was associated with decreased levels of miR-15b. Also, in human skin, highest copy numbers of miR-15b mRNA were detected in the epidermis, and epidermal expression was significantly reduced in photoaged skin as compared with intrinsically aged skin. Reduced miR-15b expression is most likely causally linked to increased SIRT4 expression because we found that (i) miR-15b displays a conserved and direct binding site within the 3'-untranslated region of the SIRT4 gene as demonstrated by luciferase reporter assays and (ii) transfection of oligonucleotides mimicking miR-15b function was sufficient to prevent SIRT4 upregulation in senescent cells in vitro. Thus, we propose that miR-15b acts as a negative regulator of SIRT4 expression to antagonize mitochondrial dysfunction and hence cellular senescence as well as tissue aging, in particular photoaging of the skin.

2016-06-08 | GSE45729 | GEO

Changes in mitochondrial function and browning markers of subcutaneous and visceral white adipose tissue of C57BL/6j mice from weaning to young adulthood

Project description:White adipose tissue (WAT) distribution and WAT mitochondrial function contribute to total body metabolic health throughout life, but little is known about changes following weaning. We therefore assessed changes in mitochondrial density and function in WAT depots of young mice. Inguinal (ING), epididymal (EPI) and retroperitoneal (RP) WAT of 21, 42 and 98 days old C57BL/6j mice was collected. Mitochondrial density (citrate synthase (CS), mtDNA) and function (subunits of oxidative phosphorylation complexes (OXPHOS)) markers were analysed, together with gene expression of browning markers (Ucp1, Cidea). RNA of ING WAT of 21 and 98 old mice was sequenced to further investigate functional changes of the mitochondria and alterations in cell populations. CS levels decreased significantly over time in all depots. ING showed most pronounced changes, including significantly decreased levels of OXPHOS complex I, II and III subunits and gene expression of Ucp1 (PN21-42 and PN42-98) and Cidea (PN42-98). White adipocyte markers were higher at PN98 in ING WAT. The mitochondrial functional profile changed over time from ‘growing’ mitochondria focused on ATP production (and dissipation), to more steady-state mitochondria with more diverse functions and higher biosynthesis. Mitochondrial density and energy metabolism markers declined in all three depots over time after weaning. This was most pronounced in ING WAT where it was associated with reduced browning markers, increased whitening and an altered metabolism. In particular the PN21-42 period may provide a time window to study mitochondrial adaptation and effects of nutritional exposures relevant for later life metabolic health.

2019-06-21 | GSE116313 | GEO

The importance of adipose tissue NAD+ biology in regulating metabolic flexibility.

Project description:Nicotinamide adenine dinucleotide (NAD+) is an essential coenzyme regulating cellular energy metabolism across all species. Recent studies have shown the pleiotropic roles of adipose tissue NAD+ biology in adipose tissue and whole-body metabolism. The major purpose of the present study was to test the hypothesis that adipose tissue NAD+ biosynthesis, mediated by nicotinamide phosphoribosyltransferase (NAMPT), is a physiological regulator of whole-body metabolic flexibility. To this end, we analyzed adipocyte-specific Nampt knockout (ANKO) mice and subcutaneous white adipose tissue (WAT) biopsy samples obtained from human subjects. We found ANKO mice preferably utilized glucose substrate during the light period or after prolonged fasting. In contrast, ANKO mice had marked decreases in stimulation of glucose oxidation and suppression of fat oxidation during the postprandial status despite hyperinsulinemia. Data obtained from RNA-sequencing of WAT suggest that loss of NAMPT causes inflammation, oxidative stress, defective fatty acid oxidation, and mitochondrial dysfunction in WAT, key features of obesity and metabolic inflexibility. We also found WAT NAD+ concentration was decreased in people with obesity and insulin resistance compared with those who were non-obese and insulin-sensitive. In addition, bariatric surgery-induced 20% weight loss increased WAT NAD+ concentration in people with obesity. Taken together, our results reveal the importance of adipose tissue NAMPT-mediated NAD+ biosynthesis in regulating whole-body metabolic flexibility. Our results also provide translational and clinical insight into adipose tissue NAD+ biology in obesity and whole-body metabolic health.

2021-07-01 | GSE159397 | GEO

Muscle mitochondrial stress-induced metabolic adaptations do not require FGF21 action

Project description:Fibroblast growth factor 21 (FGF21) is a key metabolic regulator which was recently discovered as stress-induced myokine and common denominator of muscle mitochondrial disease. However, its precise function and pathophysiological relevance remains unknown. Here we demonstrate that white adipose tissue (WAT) is the major target of muscle mitochondrial stress-induced FGF21. Strikingly, substantial browning and metabolic remodeling of subcutaneous WAT, together with the reduction of circulating triglycerides and cholesterol are fully FGF21 dependent. Unexpectedly and in contrast to prior expectations, we found a negligible role of FGF21 in muscle stress-related improved glycemic control, obesity resistance and hepatic lipid homeostasis. Furthermore, we show that the protective muscle mitohormesis and metabolic stress adaptation does not require FGF21 action. Taken together, our data imply that although FGF21 drives WAT remodeling, this effect and FGF21 as stress hormone per se may not be essential for the adaptive response under muscle mitochondrial stress conditions. Wildtype male mice and FGF21-knockout male mice, together with muscle specific UCP1-transgenic male animals, and double cross of FGF21-KO with UCP1-Tg male mice, were kept on a standardized low fat diet for 40 weeks. After sacrifice, subcutaneous white adipose tisseu (scWAT) was rapidly removed, weighed, and snap frozen in liquid nitrogen and used for RNA isolation and whole genome gene expression microarray hybridisation using Agilent arrays.

2016-01-07 | E-GEOD-71749 | biostudies-arrayexpress

STAT1 Dissociates Adipose Tissue Inflammation from Insulin Sensitivity in Obesity

Project description:Purpose: To determine how STAT1 activity in white adipocytes affects insulin sensitivity. Methods: Adipocyte specific (ADIPOQ-Cre) STAT1 fl/fl mice (STAT1 fKO) and littermate controls (STAT1 fl/fl) were placed on 60% HFD for 18 weeks, followed by metabolic phenoptying and tissue harvest for RNA-seq Results: STAT1 expression in WAT inversely correlated with fasting plasma glucose in both obese mice and humans. Metabolomic and gene expression profiling established STAT1 deletion in adipocytes (STAT1 fKO) enhanced mitochondrial function and accelerated TCA cycle flux coupled with subcutaneous WAT hyperplasia. STAT1 fKO reduced WAT inflammation, but insulin resistance persisted in obese mice. Rather, elimination of type I cytokine interferon gamma (IFNg) activity enhanced insulin sensitivity in diet-induced obesity. Conclusions: Our findings reveal a permissive mechanism that bridges WAT inflammation to whole-body insulin sensitivity.

2020-11-27 | GSE153337 | GEO

Glycemic index differences of high-fat diets modulate primarily lipid metabolism in murine adipose tissue

Project description:We previously reported that a low versus high glycemic index (GI) diet on a high fat (30% kcal fat) background (LGI and HGI, respectively) significantly retarded adverse health effects in C57BL/6J male mice. The LGI diet enhanced whole body insulin sensitivity and repressed high fat diet-induced body and adipose tissue weight gain, resulting in reduced serum leptin and resistin levels (Faseb J 2009; 23: 1092-1101). How white adipose tissue (WAT) is effected is examined in the present study. We characterized the molecular mechanisms underlying the GI-mediated effects in WAT using whole genome transcriptomics technology. We show that a LGI vs. HGI diet mainly exerts its beneficial effects on substrate metabolism, especially insulin signaling of fatty acid metabolism. In addition, cell adhesion and cytoskeleton remodeling showed reduced expression in line with lower WAT mass, but it might also be due to altered insulin sensitivity. An important transcription factor showing enhanced expression is PPARgamma. Furthermore, serum levels of triglycerides, total cholesterol, HDL- and LDL-cholesterol were significantly reduced by a LGI vs. HGI diet, and muscle insulin sensitivity was significantly increased as analyzed by PKB/Akt phosphorylation. Cumulatively, even though these mice were fed a high fat diet, the low versus high GI induced significantly favorable changes in metabolism in WAT. These effects suggest a partial overlap with pharmacological approaches by thiazolidinediones (TZDs) to treat insulin resistance and statins and plantsterols/stanols for hypercholesterolemia. It is therefore tempting to speculate that such a dietary approach might beneficially support pharmacological treatment of insulin resistance or hypercholesterolemia in humans.

2011-09-13 | GSE26930 | GEO

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data