scholarly journals Endothelial-specific FoxO1 depletion prevents obesity-related disorders by increasing vascular metabolism and growth

eLife ◽  
2018 ◽  
Vol 7 ◽  
Author(s):  
Martina Rudnicki ◽  
Ghoncheh Abdifarkosh ◽  
Emmanuel Nwadozi ◽  
Sofhia V Ramos ◽  
Armin Makki ◽  
...  

Impaired angiogenesis is a hallmark of metabolically dysfunctional adipose tissue in obesity. However, the underlying mechanisms restricting angiogenesis within this context remain ill-defined. Here, we demonstrate that induced endothelial-specific depletion of the transcription factor Forkhead Box O1 (FoxO1) in male mice led to increased vascular density in adipose tissue. Upon high-fat diet feeding, endothelial cell FoxO1-deficient mice exhibited even greater vascular remodeling in the visceral adipose depot, which was paralleled with a healthier adipose tissue expansion, higher glucose tolerance and lower fasting glycemia concomitant with enhanced lactate levels. Mechanistically, FoxO1 depletion increased endothelial proliferative and glycolytic capacities by upregulating the expression of glycolytic markers, which may account for the improvements at the tissue level ultimately impacting whole-body glucose metabolism. Altogether, these findings reveal the pivotal role of FoxO1 in controlling endothelial metabolic and angiogenic adaptations in response to high-fat diet and a contribution of the endothelium to whole-body energy homeostasis.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Pola J. Verschoor ◽  
Fiona H. Greig ◽  
Justin J. Rochford ◽  
Giovanni Levate ◽  
Mirela Delibegovic ◽  
...  

AbstractExcessive expansion of adipose tissue in obesity typically leads to overflow and accumulation of lipids in other tissues, causing fatty liver disease and atherosclerosis. The intracellular protein, phosphoprotein enriched in astrocytes (PEA)-15 has been linked to metabolic disease but its role in lipid storage has not been examined. To delineate the role of PEA-15 in adipose tissue, we placed PEA-15−/− mice on a high fat diet. These mice developed increased body weight and greater white adipose tissue expansion compared to high fat diet-fed wild type mice. This was due to increased adipocyte cell size in PEA-15−/− mice consistent with greater lipid storage capacity. Surprisingly, PEA-15−/− mice exhibited improvements in whole body insulin sensitivity, lower hepatic weight and decreased serum triglycerides indicating a protective phenotype. To determine effects on atherosclerosis, PEA-15−/− mice were crossed with the ApoE−/− mice on a high fat diet. Strikingly, these mice were protected from atherosclerosis and had less hepatic lipid accumulation despite increased adiposity. Therefore, we reveal for the first time that PEA-15 plays a novel role in regulating the expansion of adipose tissue. Decreasing PEA-15 expression increases the sequestering of lipids in adipose tissue, protecting other tissues in obesity, thereby improving metabolic health.


2011 ◽  
Vol 108 (6) ◽  
pp. 1025-1033 ◽  
Author(s):  
Sumithra Urs ◽  
Terry Henderson ◽  
Phuong Le ◽  
Clifford J. Rosen ◽  
Lucy Liaw

We recently characterised Sprouty1 (Spry1), a growth factor signalling inhibitor as a regulator of marrow progenitor cells promoting osteoblast differentiation at the expense of adipocytes. Adipose tissue-specific Spry1 expression in mice resulted in increased bone mass and reduced body fat, while conditional knockout of Spry1 had the opposite effect with decreased bone mass and increased body fat. Because Spry1 suppresses normal fat development, we tested the hypothesis that Spry1 expression prevents high-fat diet-induced obesity, bone loss and associated lipid abnormalities, and demonstrate that Spry1 has a long-term protective effect on mice fed a high-energy diet. We studied diet-induced obesity in mice with fatty acid binding promoter-driven expression or conditional knockout of Spry1 in adipocytes. Phenotyping was performed by whole-body dual-energy X-ray absorptiometry, microCT, histology and blood analysis. In conditional Spry1-null mice, a high-fat diet increased body fat by 40 %, impaired glucose regulation and led to liver steatosis. However, overexpression of Spry1 led to 35 % (P < 0·05) lower body fat, reduced bone loss and normal metabolic function compared with single transgenics. This protective phenotype was associated with decreased circulating insulin (70 %) and leptin (54 %; P < 0·005) compared with controls on a high-fat diet. Additionally, Spry1 expression decreased adipose tissue inflammation by 45 %. We show that conditional Spry1 expression in adipose tissue protects against high-fat diet-induced obesity and associated bone loss.


2012 ◽  
Vol 302 (5) ◽  
pp. E532-E539 ◽  
Author(s):  
Haihong Zong ◽  
Michal Armoni ◽  
Chava Harel ◽  
Eddy Karnieli ◽  
Jeffrey E. Pessin

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.


Author(s):  
Peter Aldiss ◽  
Jo Lewis ◽  
David Boocock ◽  
Amanda Miles ◽  
Ian Bloor ◽  
...  

Brown adipose tissue (BAT) function may depend on its anatomical location and developmental origin. Interscapular BAT (iBAT) regulates acute macronutrient metabolism, whilst perivascular BAT (PVAT) regulates vascular function. Although phenotypically similar, whether these depots respond differently to acute nutrient excess is unclear. Given their distinct anatomical locations and developmental origins and we hypothesised that iBAT and PVAT would respond differently to brief period of nutrient excess. Sprague-Dawley rats aged 12 weeks (n = 12) were fed either a standard (10% fat, n = 6) or high fat diet (HFD: 45% fat, n = 6) for 72 h and housed at thermoneutrality. Following an assessment of whole body physiology, fat was collected from both depots for analysis of gene expression and the proteome. HFD consumption for 72 h induced rapid weight gain (c. 2.6%) and reduced serum NEFA with no change in either total adipose or depot mass. In iBAT, an upregulation of genes involved in insulin signalling and lipid metabolism was accompanied by enrichment of lipid-related processes and functions, plus glucagon and PPAR signalling pathways. In PVAT, HFD induced a pronounced down-regulation of multiple metabolic pathways which was accompanied with increased abundance of proteins involved in apoptosis (e.g. Hdgf and Ywaq) and toll-like receptor signalling (Ube2n). There was also an enrichment of DNA-related processes and functions (e.g., nucleosome assembly and histone exchange) and RNA degradation and cell adhesion pathways. In conclusion, we show that iBAT and PVAT elicit divergent responses to short-term nutrient excess highlighting early adaptations in these depots before changes in fat mass.


Nutrients ◽  
2019 ◽  
Vol 11 (5) ◽  
pp. 1065 ◽  
Author(s):  
Peter Aldiss ◽  
Jo E. Lewis ◽  
David J. Boocock ◽  
Amanda K. Miles ◽  
Ian Bloor ◽  
...  

Brown adipose tissue (BAT) function may depend on its anatomical location and developmental origin. Interscapular BAT (iBAT) regulates acute macronutrient metabolism, whilst perivascular BAT (PVAT) regulates vascular function. Although phenotypically similar, whether these depots respond differently to acute nutrient excess is unclear. Given their distinct anatomical locations and developmental origins and we hypothesised that iBAT and PVAT would respond differently to brief period of nutrient excess. Sprague-Dawley rats aged 12 weeks (n=12) were fed either a standard (10% fat, n=6) or high fat diet (HFD: 45% fat, n=6) for 72h and housed at thermoneutrality. Following an assessment of whole body physiology, fat was collected from both depots for analysis of gene expression and the proteome. HFD consumption for 72h induced rapid weight gain (c. 2.6%) and reduced serum non-esterified fatty acids (NEFA) with no change in either total adipose or depot mass. In iBAT, an upregulation of genes involved in insulin signalling and lipid metabolism was accompanied by enrichment of lipid-related processes and functions, plus glucagon and peroxisome proliferator-activated receptor (PPAR) signalling pathways. In PVAT, HFD induced a pronounced down-regulation of multiple metabolic pathways which was accompanied with increased abundance of proteins involved in apoptosis (e.g., Hdgf and Ywaq) and toll-like receptor signalling (Ube2n). There was also an enrichment of DNA-related processes and functions (e.g., nucleosome assembly and histone exchange) and RNA degradation and cell adhesion pathways. In conclusion, we show that iBAT and PVAT elicit divergent responses to short-term nutrient excess highlighting early adaptations in these depots before changes in fat mass.


Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1059
Author(s):  
Si Fan ◽  
Samnhita Raychaudhuri ◽  
Olivia Kraus ◽  
Md Shahinozzaman ◽  
Leila Lofti ◽  
...  

The shoot of Urtica dioica is used in several cultures as a vegetable or herb. However, not much has been studied about the potential of this plant when consumed as a whole food/vegetable rather than an extract for dietary supplements. In a 12-week dietary intervention study, we tested the effect of U. dioica vegetable on high fat diet induced obesity and insulin resistance in C57BL/6J mice. Mice were fed ad libitum with isocaloric diets containing 10% fat or 45% fat with or without U. dioica. The diet supplemented with U. dioica attenuated high fat diet induced weight gain (p < 0.005; n = 9), fat accumulation in adipose tissue (p < 0.005; n = 9), and whole-body insulin resistance (HOMA-IR index) (p < 0.001; n = 9). Analysis of gene expression in skeletal muscle showed no effect on the constituents of the insulin signaling pathway (AKT, IRS proteins, PI3K, GLUT4, and insulin receptor). Notable genes that impact lipid or glucose metabolism and whose expression was changed by U. dioica include fasting induced adipocyte factor (FIAF) in adipose and skeletal muscle, peroxisome proliferator-activated receptor-α (Ppar-α) and forkhead box protein (FOXO1) in muscle and liver, and Carnitine palmitoyltransferase I (Cpt1) in liver (p < 0.01). We conclude that U. dioica vegetable protects against diet induced obesity through mechanisms involving lipid accumulation and glucose metabolism in skeletal muscle, liver, and adipose tissue.


2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Cuiqing Liu ◽  
Guohua Lin ◽  
Guoqing Zhang ◽  
Huanhuan Wang ◽  
Hongping Yin ◽  
...  

Inflammation in insulin sensitive tissues, the visceral adipose tissue (VAT), is a central abnormality in obesity/insulin resistance (IR), with recruitment of innate immune cells such as monocytes into adipose tissue driving the development of glucose and lipoprotein dysregulation. We evaluated the role of Toll like receptor 3 (TLR3) in high fat diet-induced obesity and IR. Wild-type C57BL/6 and TLR3 -/- male mice were fed a high fat diet for 15 weeks. High fat feeding resulted in increased TLR3 expression in VAT. TLR3 deficiency attenuated the high fat diet-increased body weight, fasting blood glucose, whole body IR and impaired glucose tolerance. Morphologically, high fat diet induced adiposity and enlarged adipocyte area in VAT, which were attenuated in TLR3 -/- mice. Functionally, high fat diet induced dysregulation of adipocytokines such as downregulation of adiponectin and resistin, upregulation of leptin in VAT, with the disturbance of adiponectin and leptin was corrected in TLR3-/- mice. In addition, high fat diet inhibited insulin pathway, accompanied with decreased phosphorylation of AMPK and lowered expression of lipolysis-related enzymes such as HSL and ATGL, both at the mRNA levels and protein levels, all of which was corrected by TLR3 deficiency. Finally, TLR3 deletion suppressed the high fat feeding-mediated macrophage polarization, evidenced by increased type M1 macrophage (F4/80+/CD11c+/CD206-) infiltration and upregulation of M1 genes such as IL-6 and TNFα. TLR3 modulates high fat diet-induced IR and obesity by suppressing M1 macrophage-mediated VAT inflammation, facilitating secretion of adipocyte-derived hormones, thus enhanced AMPK activity and adipose lipolysis. These findings provide new mechanistic links between dietary factors-mediated IR and associated abnormalities in lipid metabolism and adipose inflammation.


2013 ◽  
Vol 304 (10) ◽  
pp. E1053-E1063 ◽  
Author(s):  
Johanna L. Barclay ◽  
Anton Shostak ◽  
Alexei Leliavski ◽  
Anthony H. Tsang ◽  
Olaf Jöhren ◽  
...  

Perturbation of circadian rhythmicity in mammals, either by environmental influences such as shiftwork or by genetic manipulation, has been associated with metabolic disturbance and the development of obesity and diabetes. Circadian clocks are based on transcriptional/translational feedback loops, comprising positive and negative components. Whereas the metabolic effects of deletion of the positive arm of the clock gene machinery, as in Clock- or Bmal1-deficient mice, have been well characterized, inactivation of Period genes ( Per1–3) as components of the negative arm have more complex, sometimes contradictory effects on energy homeostasis. The CRYPTOCHROMEs are critical interaction partners of PERs, and simultaneous deletion of Cry1 and - 2 results in behavioral and molecular circadian arrhythmicity. We show that, when challenged with a high-fat diet, Cry1/2−/− mice rapidly gain weight and surpass that of wild-type mice, despite displaying hypophagia. Transcript analysis of white adipose tissue reveals upregulated expression of lipogenic genes, many of which are insulin targets. High-fat diet-induced hyperinsulinemia, as a result of potentiated insulin secretion, coupled with selective insulin sensitivity in adipose tissue of Cry1/2−/− mice, correlates with increased lipid uptake. Collectively, these data indicate that Cry deficiency results in an increased vulnerability to high-fat diet-induced obesity that might be mediated by increased insulin secretion and lipid storage in adipose tissues.


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