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Goerdeler C, Engelmann B, Aldehoff AS, Schaffert A, Blüher M, Heiker JT, Wabitsch M, Schubert K, Rolle-Kampczyk U, von Bergen M. Metabolomics in human SGBS cells as new approach method for studying adipogenic effects: Analysis of the effects of DINCH and MINCH on central carbon metabolism. ENVIRONMENTAL RESEARCH 2024; 252:118847. [PMID: 38582427 DOI: 10.1016/j.envres.2024.118847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 03/20/2024] [Accepted: 03/31/2024] [Indexed: 04/08/2024]
Abstract
Growing evidence suggests that exposure to certain metabolism-disrupting chemicals (MDCs), such as the phthalate plasticizer DEHP, might promote obesity in humans, contributing to the spread of this global health problem. Due to the restriction on the use of phthalates, there has been a shift to safer declared substitutes, including the plasticizer diisononyl-cyclohexane-1,2-dicarboxylate (DINCH). Notwithstanding, recent studies suggest that the primary metabolite monoisononyl-cyclohexane-1,2-dicarboxylic acid ester (MINCH), induces differentiation of human adipocytes and affects enzyme levels of key metabolic pathways. Given the lack of methods for assessing metabolism-disrupting effects of chemicals on adipose tissue, we used metabolomics to analyze human SGSB cells exposed to DINCH or MINCH. Concentration analysis of DINCH and MINCH revealed that uptake of MINCH in preadipocytes was associated with increased lipid accumulation during adipogenesis. Although we also observed intracellular uptake for DINCH, the solubility of DINCH in cell culture medium was limited, hampering the analysis of possible effects in the μM concentration range. Metabolomics revealed that MINCH induces lipid accumulation similar to peroxisome proliferator-activated receptor gamma (PPARG)-agonist rosiglitazone through upregulation of the pyruvate cycle, which was recently identified as a key driver of de novo lipogenesis. Analysis of the metabolome in the presence of the PPARG-inhibitor GW9662 indicated that the effect of MINCH on metabolism was mediated at least partly by a PPARG-independent mechanism. However, all effects of MINCH were only observed at high concentrations of 10 μM, which are three orders of magnitudes higher than the current concentrations of plasticizers in human serum. Overall, the assessment of the effects of DINCH and MINCH on SGBS cells by metabolomics revealed no adipogenic potential at physiologically relevant concentrations. This finding aligns with previous in vivo studies and supports the potential of our method as a New Approach Method (NAM) for the assessment of adipogenic effects of environmental chemicals.
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Affiliation(s)
- Cornelius Goerdeler
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Beatrice Engelmann
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Alix Sarah Aldehoff
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Alexandra Schaffert
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Matthias Blüher
- Department of Endocrinology, Nephrology and Rheumatology, Faculty of Medicine, University of Leipzig, Leipzig, Germany; Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany.
| | - John T Heiker
- Helmholtz Institute for Metabolic, Obesity and Vascular Research (HI-MAG) of the Helmholtz Zentrum München at the University of Leipzig and University Hospital Leipzig, Leipzig, Germany.
| | - Martin Wabitsch
- Division of Pediatric Endocrinology and Diabetes, Ulm University Medical Center, Ulm, Germany.
| | - Kristin Schubert
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Ulrike Rolle-Kampczyk
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany.
| | - Martin von Bergen
- Department of Molecular Toxicology, Helmholtz Centre for Environmental Research (UFZ), Leipzig, Germany; Institute of Biochemistry, Leipzig University, Leipzig, Germany; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany.
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Sharma AK, Khandelwal R, Wolfrum C. Futile cycles: Emerging utility from apparent futility. Cell Metab 2024; 36:1184-1203. [PMID: 38565147 DOI: 10.1016/j.cmet.2024.03.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/05/2024] [Revised: 02/15/2024] [Accepted: 03/11/2024] [Indexed: 04/04/2024]
Abstract
Futile cycles are biological phenomena where two opposing biochemical reactions run simultaneously, resulting in a net energy loss without appreciable productivity. Such a state was presumed to be a biological aberration and thus deemed an energy-wasting "futile" cycle. However, multiple pieces of evidence suggest that biological utilities emerge from futile cycles. A few established functions of futile cycles are to control metabolic sensitivity, modulate energy homeostasis, and drive adaptive thermogenesis. Yet, the physiological regulation, implication, and pathological relevance of most futile cycles remain poorly studied. In this review, we highlight the abundance and versatility of futile cycles and propose a classification scheme. We further discuss the energetic implications of various futile cycles and their impact on basal metabolic rate, their bona fide and tentative pathophysiological implications, and putative drug interactions.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
| | - Radhika Khandelwal
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
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Sahin C, Melanson JR, Le Billan F, Magomedova L, Ferreira TAM, Oliveira AS, Pollock-Tahari E, Saikali MF, Cash SB, Woo M, Romeiro LAS, Cummins CL. A novel fatty acid mimetic with pan-PPAR partial agonist activity inhibits diet-induced obesity and metabolic dysfunction-associated steatotic liver disease. Mol Metab 2024; 85:101958. [PMID: 38763495 PMCID: PMC11170206 DOI: 10.1016/j.molmet.2024.101958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Revised: 05/09/2024] [Accepted: 05/13/2024] [Indexed: 05/21/2024] Open
Abstract
OBJECTIVE The prevalence of metabolic diseases is increasing globally at an alarming rate; thus, it is essential that effective, accessible, low-cost therapeutics are developed. Peroxisome proliferator-activated receptors (PPARs) are transcription factors that tightly regulate glucose homeostasis and lipid metabolism and are important drug targets for the treatment of type 2 diabetes and dyslipidemia. We previously identified LDT409, a fatty acid-like compound derived from cashew nut shell liquid, as a novel pan-active PPARα/γ/δ compound. Herein, we aimed to assess the efficacy of LDT409 in vivo and investigate the molecular mechanisms governing the actions of the fatty acid mimetic LDT409 in diet-induced obese mice. METHODS C57Bl/6 mice (6-11-month-old) were fed a chow or high fat diet (HFD) for 4 weeks; mice thereafter received once daily intraperitoneal injections of vehicle, 10 mg/kg Rosiglitazone, 40 mg/kg WY14643, or 40 mg/kg LDT409 for 18 days while continuing the HFD. During treatments, body weight, food intake, glucose and insulin tolerance, energy expenditure, and intestinal lipid absorption were measured. On day 18 of treatment, tissues and plasma were collected for histological, molecular, and biochemical analysis. RESULTS We found that treatment with LDT409 was effective at reversing HFD-induced obesity and associated metabolic abnormalities in mice. LDT409 lowered food intake and hyperlipidemia, while improving insulin tolerance. Despite being a substrate of both PPARα and PPARγ, LDT409 was crucial for promoting hepatic fatty acid oxidation and reducing hepatic steatosis in HFD-fed mice. We also highlighted a role for LDT409 in white and brown adipocytes in vitro and in vivo where it decreased fat accumulation, increased lipolysis, induced browning of WAT, and upregulated thermogenic gene Ucp1. Remarkably, LDT409 reversed HFD-induced weight gain back to chow-fed control levels. We determined that the LDT409-induced weight-loss was associated with a combination of increased energy expenditure (detectable before weight loss was apparent), decreased food intake, increased systemic fat utilization, and increased fecal lipid excretion in HFD-fed mice. CONCLUSIONS Collectively, LDT409 represents a fatty acid mimetic that generates a uniquely favorable metabolic response for the treatment of multiple abnormalities including obesity, dyslipidemia, metabolic dysfunction-associated steatotic liver disease, and diabetes. LDT409 is derived from a highly abundant natural product-based starting material and its development could be pursued as a therapeutic solution to the global metabolic health crisis.
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Affiliation(s)
- Cigdem Sahin
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Jenna-Rose Melanson
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Florian Le Billan
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Lilia Magomedova
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Thais A M Ferreira
- Department of Pharmacy, Faculty of Health Sciences, University of Brasilia, Brasilia, DF 71910-900, Brazil
| | - Andressa S Oliveira
- Department of Pharmacy, Faculty of Health Sciences, University of Brasilia, Brasilia, DF 71910-900, Brazil
| | - Evan Pollock-Tahari
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, M5G 2C4, Canada
| | - Michael F Saikali
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Sarah B Cash
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada
| | - Minna Woo
- Toronto General Hospital Research Institute, University Health Network, Toronto, ON, M5G 2C4, Canada; Banting and Best Diabetes Centre, Toronto, ON, M5G 2C4, Canada
| | - Luiz A S Romeiro
- Department of Pharmacy, Faculty of Health Sciences, University of Brasilia, Brasilia, DF 71910-900, Brazil
| | - Carolyn L Cummins
- Department of Pharmaceutical Sciences, Leslie Dan Faculty of Pharmacy, University of Toronto, Toronto, ON M5S 3M2, Canada; Banting and Best Diabetes Centre, Toronto, ON, M5G 2C4, Canada.
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Shannon CE, Bakewell T, Fourcaudot MJ, Ayala I, Romero G, Asmis M, Lima LCF, Wallace M, Norton L. Sex-dependent adipose glucose partitioning by the mitochondrial pyruvate carrier. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.11.593540. [PMID: 38798427 PMCID: PMC11118482 DOI: 10.1101/2024.05.11.593540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Objective The mitochondrial pyruvate carrier (MPC) occupies a critical node in intermediary metabolism, prompting interest in its utility as a therapeutic target for the treatment of obesity and cardiometabolic disease. Dysregulated nutrient metabolism in adipose tissue is a prominent feature of obesity pathophysiology, yet the functional role of adipose MPC has not been explored. We investigated whether the MPC shapes the adaptation of adipose tissue to dietary stress in female and male mice. Methods The impact of pharmacological and genetic disruption of the MPC on mitochondrial pathways of triglyceride assembly (lipogenesis and glyceroneogenesis) was assessed in 3T3L1 adipocytes and murine adipose explants, combined with analyses of adipose MPC expression in metabolically compromised humans. Whole-body and adipose-specific glucose metabolism were subsequently investigated in male and female mice lacking adipocyte MPC1 (Mpc1AD-/-) and fed either standard chow, high-fat western style, or high-sucrose lipid restricted diets for 24 weeks, using a combination of radiolabeled tracers and GC/MS metabolomics. Results Treatment with UK5099 or siMPC1 impaired the synthesis of lipids and glycerol-3-phosphate from pyruvate and blunted triglyceride accumulation in 3T3L1 adipocytes, whilst MPC expression in human adipose tissue was negatively correlated with indices of whole-body and adipose tissue metabolic dysfunction. Mature adipose explants from Mpc1AD-/- mice were intrinsically incapable of incorporating pyruvate into triglycerides. In vivo, MPC deletion restricted the incorporation of circulating glucose into adipose triglycerides, but only in female mice fed a zero fat diet, and this associated with sex-specific reductions in tricarboxylic acid cycle pool sizes and compensatory transcriptional changes in lipogenic and glycerol metabolism pathways. However, whole-body adiposity and metabolic health were preserved in Mpc1AD-/- mice regardless of sex, even under conditions of zero dietary fat. Conclusion These findings highlight the greater capacity for mitochondrially driven triglyceride assembly in adipose from female versus male mice and expose a reliance upon MPC-gated metabolism for glucose partitioning in female adipose under conditions of dietary lipid restriction.
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Affiliation(s)
- Christopher E Shannon
- UCD Conway Institute, School of Medicine, University College Dublin, Dublin, Ireland
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Terry Bakewell
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Marcel J Fourcaudot
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Iriscilla Ayala
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Giovanna Romero
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Mara Asmis
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Leandro C Freitas Lima
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
| | - Martina Wallace
- UCD Conway Institute, School of Agriculture and Food Science, University College Dublin, Dublin, Ireland
| | - Luke Norton
- Diabetes Division, Department of Medicine, University of Texas Health San Antonio, San Antonio, TX, USA
- Department of Cell Systems and Anatomy, University of Texas Health San Antonio, San Antonio, TX, USA
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Sharma AK, Khandelwal R, Wolfrum C. Futile lipid cycling: from biochemistry to physiology. Nat Metab 2024; 6:808-824. [PMID: 38459186 DOI: 10.1038/s42255-024-01003-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/23/2023] [Accepted: 02/02/2024] [Indexed: 03/10/2024]
Abstract
In the healthy state, the fat stored in our body isn't just inert. Rather, it is dynamically mobilized to maintain an adequate concentration of fatty acids (FAs) in our bloodstream. Our body tends to produce excess FAs to ensure that the FA availability is not limiting. The surplus FAs are actively re-esterified into glycerides, initiating a cycle of breakdown and resynthesis of glycerides. This cycle consumes energy without generating a new product and is commonly referred to as the 'futile lipid cycle' or the glyceride/FA cycle. Contrary to the notion that it's a wasteful process, it turns out this cycle is crucial for systemic metabolic homeostasis. It acts as a control point in intra-adipocyte and inter-organ cross-talk, a metabolic rheostat, an energy sensor and a lipid diversifying mechanism. In this Review, we discuss the metabolic regulation and physiological implications of the glyceride/FA cycle and its mechanistic underpinnings.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
| | - Radhika Khandelwal
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Schwerzenbach, Switzerland.
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Iacobini C, Vitale M, Haxhi J, Menini S, Pugliese G. Impaired Remodeling of White Adipose Tissue in Obesity and Aging: From Defective Adipogenesis to Adipose Organ Dysfunction. Cells 2024; 13:763. [PMID: 38727299 PMCID: PMC11083890 DOI: 10.3390/cells13090763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2024] [Revised: 04/22/2024] [Accepted: 04/25/2024] [Indexed: 05/13/2024] Open
Abstract
The adipose organ adapts and responds to internal and environmental stimuli by remodeling both its cellular and extracellular components. Under conditions of energy surplus, the subcutaneous white adipose tissue (WAT) is capable of expanding through the enlargement of existing adipocytes (hypertrophy), followed by de novo adipogenesis (hyperplasia), which is impaired in hypertrophic obesity. However, an impaired hyperplastic response may result from various defects in adipogenesis, leading to different WAT features and metabolic consequences, as discussed here by reviewing the results of the studies in animal models with either overexpression or knockdown of the main molecular regulators of the two steps of the adipogenesis process. Moreover, impaired WAT remodeling with aging has been associated with various age-related conditions and reduced lifespan expectancy. Here, we delve into the latest advancements in comprehending the molecular and cellular processes underlying age-related changes in WAT function, their involvement in common aging pathologies, and their potential as therapeutic targets to influence both the health of elderly people and longevity. Overall, this review aims to encourage research on the mechanisms of WAT maladaptation common to conditions of both excessive and insufficient fat tissue. The goal is to devise adipocyte-targeted therapies that are effective against both obesity- and age-related disorders.
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7
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Naren Q, Lindsund E, Bokhari MH, Pang W, Petrovic N. Differential responses to UCP1 ablation in classical brown versus beige fat, despite a parallel increase in sympathetic innervation. J Biol Chem 2024; 300:105760. [PMID: 38367663 PMCID: PMC10944106 DOI: 10.1016/j.jbc.2024.105760] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 01/27/2024] [Accepted: 02/09/2024] [Indexed: 02/19/2024] Open
Abstract
In the cold, the absence of the mitochondrial uncoupling protein 1 (UCP1) results in hyper-recruitment of beige fat, but classical brown fat becomes atrophied. Here we examine possible mechanisms underlying this phenomenon. We confirm that in brown fat from UCP1-knockout (UCP1-KO) mice acclimated to the cold, the levels of mitochondrial respiratory chain proteins were diminished; however, in beige fat, the mitochondria seemed to be unaffected. The macrophages that accumulated massively not only in brown fat but also in beige fat of the UCP1-KO mice acclimated to cold did not express tyrosine hydroxylase, the norepinephrine transporter (NET) and monoamine oxidase-A (MAO-A). Consequently, they could not influence the tissues through the synthesis or degradation of norepinephrine. Unexpectedly, in the cold, both brown and beige adipocytes from UCP1-KO mice acquired an ability to express MAO-A. Adipose tissue norepinephrine was exclusively of sympathetic origin, and sympathetic innervation significantly increased in both tissues of UCP1-KO mice. Importantly, the magnitude of sympathetic innervation and the expression levels of genes induced by adrenergic stimulation were much higher in brown fat. Therefore, we conclude that no qualitative differences in innervation or macrophage character could explain the contrasting reactions of brown versus beige adipose tissues to UCP1-ablation. Instead, these contrasting responses may be explained by quantitative differences in sympathetic innervation: the beige adipose depot from the UCP1-KO mice responded to cold acclimation in a canonical manner and displayed enhanced recruitment, while the atrophy of brown fat lacking UCP1 may be seen as a consequence of supraphysiological adrenergic stimulation in this tissue.
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Affiliation(s)
- Qimuge Naren
- College of Animal Science and Technology, Northwest A&F University, Yangling, China; Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Erik Lindsund
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Muhammad Hamza Bokhari
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden
| | - Weijun Pang
- College of Animal Science and Technology, Northwest A&F University, Yangling, China.
| | - Natasa Petrovic
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, Stockholm, Sweden.
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Chang CF, Gunawan AL, Liparulo I, Zushin PJH, Vitangcol K, Timblin GA, Saijo K, Wang B, Parlakgül G, Arruda AP, Stahl A. Brown adipose tissue CoQ deficiency activates the integrated stress response and FGF21-dependent mitohormesis. EMBO J 2024; 43:168-195. [PMID: 38212382 PMCID: PMC10897314 DOI: 10.1038/s44318-023-00008-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2023] [Revised: 10/27/2023] [Accepted: 11/08/2023] [Indexed: 01/13/2024] Open
Abstract
Coenzyme Q (CoQ) is essential for mitochondrial respiration and required for thermogenic activity in brown adipose tissues (BAT). CoQ deficiency leads to a wide range of pathological manifestations, but mechanistic consequences of CoQ deficiency in specific tissues, such as BAT, remain poorly understood. Here, we show that pharmacological or genetic CoQ deficiency in BAT leads to stress signals causing accumulation of cytosolic mitochondrial RNAs and activation of the eIF2α kinase PKR, resulting in activation of the integrated stress response (ISR) with suppression of UCP1 but induction of FGF21 expression. Strikingly, despite diminished UCP1 levels, BAT CoQ deficiency displays increased whole-body metabolic rates at room temperature and thermoneutrality resulting in decreased weight gain on high-fat diets (HFD). In line with enhanced metabolic rates, BAT and inguinal white adipose tissue (iWAT) interorgan crosstalk caused increased browning of iWAT in BAT-specific CoQ deficient animals. This mitohormesis-like effect depends on the ATF4-FGF21 axis and BAT-secreted FGF21, revealing an unexpected role for CoQ in the modulation of whole-body energy expenditure with wide-ranging implications for primary and secondary CoQ deficiencies.
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Affiliation(s)
- Ching-Fang Chang
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Amanda L Gunawan
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Irene Liparulo
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Peter-James H Zushin
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Kaitlyn Vitangcol
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Greg A Timblin
- Center for Bioengineering and Tissue Regeneration, Department of Surgery, University of California, San Francisco, San Francisco, CA, USA
| | - Kaoru Saijo
- Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA, 94720, USA
| | - Biao Wang
- Cardiovascular Research Institute, Department of Physiology, University of California, San Francisco, CA, 94158, USA
| | - Güneş Parlakgül
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Ana Paula Arruda
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA
| | - Andreas Stahl
- Department of Nutritional Sciences and Toxicology, University of California, Berkeley, Berkeley, CA, 94720, USA.
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Sharma AK, Wolfrum C. DGAT inhibition at the post-absorptive phase reduces plasma FA by increasing FA oxidation. EMBO Mol Med 2023; 15:e18209. [PMID: 37789773 PMCID: PMC10630880 DOI: 10.15252/emmm.202318209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Revised: 09/12/2023] [Accepted: 09/18/2023] [Indexed: 10/05/2023] Open
Abstract
In this Correspondence, A. Sharma & C. Wolfrum report that DGAT1/2 pharmacological inhibition at post-absorptive phase in mice leads to increased fatty acid oxidation and reduced plasma fatty acid levels, which could open new therapeutic avenues to avoid GI complications observed in clinical trials.
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Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition BiologyInstitute of Food, Nutrition and Health, ETH ZurichSchwerzenbachSwitzerland
| | - Christian Wolfrum
- Laboratory of Translational Nutrition BiologyInstitute of Food, Nutrition and Health, ETH ZurichSchwerzenbachSwitzerland
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10
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El-Yazbi AF, Elrewiny MA, Habib HM, Eid AH, Elzahhar PA, Belal ASF. Thermogenic Modulation of Adipose Depots: A Perspective on Possible Therapeutic Intervention with Early Cardiorenal Complications of Metabolic Impairment. Mol Pharmacol 2023; 104:187-194. [PMID: 37567782 DOI: 10.1124/molpharm.123.000704] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2023] [Revised: 08/02/2023] [Accepted: 08/03/2023] [Indexed: 08/13/2023] Open
Abstract
Cardiovascular complications of diabetes and obesity remain a major cause for morbidity and mortality worldwide. Despite significant advances in the pharmacotherapy of metabolic disease, the available approaches do not prevent or slow the progression of complications. Moreover, a majority of patients present with significant vascular involvement at early stages of dysfunction prior to overt metabolic changes. The lack of disease-modifying therapies affects millions of patients globally, causing a massive economic burden due to these complications. Significantly, adipose tissue inflammation was implicated in the pathogenesis of metabolic syndrome, diabetes, and obesity. Specifically, perivascular adipose tissue (PVAT) and perirenal adipose tissue (PRAT) depots influence cardiovascular and renal structure and function. Accumulating evidence implicates localized PVAT/PRAT inflammation as the earliest response to metabolic impairment leading to cardiorenal dysfunction. Increased mitochondrial uncoupling protein 1 (UCP1) expression and function lead to PVAT/PRAT hypoxia and inflammation as well as vascular, cardiac, and renal dysfunction. As UCP1 function remains an undruggable target so far, modulation of the augmented UCP1-mediated PVAT/PRAT thermogenesis constitutes a lucrative target for drug development to mitigate early cardiorenal involvement. This can be achieved either by subtle targeted reduction in UCP-1 expression using innovative proteolysis activating chimeric molecules (PROTACs) or by supplementation with cyclocreatine phosphate, which augments the mitochondrial futile creatine cycling and thus decreases UCP1 activity, enhances the efficiency of oxygen use, and reduces hypoxia. Once developed, these molecules will be first-in-class therapeutic tools to directly interfere with and reverse the earliest pathology underlying cardiac, vascular, and renal dysfunction accompanying the early metabolic deterioration. SIGNIFICANCE STATEMENT: Adipose tissue dysfunction plays a major role in the pathogenesis of metabolic diseases and their complications. Although mitochondrial alterations are common in metabolic impairment, it was only recently shown that the early stages of metabolic challenge involve inflammatory changes in select adipose depots associated with increased uncoupling protein 1 thermogenesis and hypoxia. Manipulating this mode of thermogenesis can help mitigate the early inflammation and the consequent cardiorenal complications.
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Affiliation(s)
- Ahmed F El-Yazbi
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
| | - Mohamed A Elrewiny
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
| | - Hosam M Habib
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
| | - Ali H Eid
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
| | - Perihan A Elzahhar
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
| | - Ahmed S F Belal
- Department of Pharmacology and Toxicology (A.F.E.-Y.) and Department of Pharmaceutical Chemistry (P.A.E., A.S.F.B.), Faculty of Pharmacy, Alexandria University, Alexandria, Egypt; Research and Innovation Hub, Alamein International University, Alamein, Egypt (A.F.E.-Y., M.A.E., H.M.H.); and Department of Basic Medical Sciences, College of Medicine, QU Health, Qatar University, Doha, Qatar (A.H.E.)
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11
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Da Eira D, Jani S, Stefanovic M, Ceddia RB. The ketogenic diet promotes triacylglycerol recycling in white adipose tissue and uncoupled fat oxidation in brown adipose tissue, but does not reduce adiposity in rats. J Nutr Biochem 2023; 120:109412. [PMID: 37422170 DOI: 10.1016/j.jnutbio.2023.109412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 06/06/2023] [Accepted: 07/03/2023] [Indexed: 07/10/2023]
Abstract
The purpose of this study was to determine whether the weight-reducing and fat burning effects of the ketogenic diet (KD) could be attributed to alterations in the energy dissipating pathways of brown adipose tissue (BAT) uncoupled oxidation, and white adipose tissue (WAT) browning and triacylglycerol (TAG) recycling. To investigate this, male Wistar rats were fed one of the following three diets for either 8 or 16 weeks: a standard chow (SC), a high-fat, sucrose-enriched (HFS) obesogenic diet, or a KD. At the end of the intervention, subcutaneous inguinal (Sc Ing) and epididymal (Epid) fat, and interscapular and aortic BAT (iBAT and aBAT, respectively) were extracted. These tissues were used for the analysis of proteins involved in WAT browning and thermogenesis. Isolated adipocytes from WAT were assayed for basal and isoproterenol (Iso)-stimulated lipolysis and basal and insulin-stimulated lipogenesis, and BAT adipocytes were assayed for the determination of coupled and uncoupled glucose and palmitate oxidation. Adiposity similarly increased in HFS- and KD-fed rats at weeks 8 and 16. However, in HFS-fed animals insulin-stimulated lipogenesis and Iso-stimulated lipolysis were impaired in WAT adipocytes, whereas in KD-fed animals these pathways remained intact. The KD also significantly elevated WAT glycerol kinase levels, and favored TAG recycling under conditions of enhanced lipolysis. In BAT, the KD significantly increased uncoupling protein-1 levels and uncoupled fat oxidation. In summary, the KD preserved insulin sensitivity and lipolytic capacity in WAT and also upregulated energy-dissipating pathways in BAT, but it was not sufficient to prevent an increase in adiposity.
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Affiliation(s)
- Daniel Da Eira
- Muscle Health Research Centre - School of Kinesiology and Health Science, York University, North York, ON, Canada
| | - Shailee Jani
- Muscle Health Research Centre - School of Kinesiology and Health Science, York University, North York, ON, Canada
| | - Mateja Stefanovic
- Muscle Health Research Centre - School of Kinesiology and Health Science, York University, North York, ON, Canada
| | - Rolando B Ceddia
- Muscle Health Research Centre - School of Kinesiology and Health Science, York University, North York, ON, Canada.
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12
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Klein Hazebroek M, Laterveer R, Kutschke M, Ramšak Marčeta V, Barthem CS, Keipert S. Hyperphagia of female UCP1-deficient mice blunts anti-obesity effects of FGF21. Sci Rep 2023; 13:10288. [PMID: 37355753 PMCID: PMC10290677 DOI: 10.1038/s41598-023-37264-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 06/19/2023] [Indexed: 06/26/2023] Open
Abstract
Increasing energy expenditure through uncoupling protein 1 (UCP1) activity in thermogenic adipose tissue is widely investigated to correct diet-induced obesity (DIO). Paradoxically, UCP1-deficient male mice are resistant to DIO at room temperature. Recently, we uncovered a key role for fibroblast growth factor 21 (FGF21), a promising drug target for treatment of metabolic disease, in this phenomenon. As the metabolic action of FGF21 is so far understudied in females, we aim to investigate potential sexual dimorphisms. Here, we confirm that male UCP1 KO mice display resistance to DIO in mild cold, without significant changes in metabolic parameters. Surprisingly, females gained the same amount of body fat as WT controls. Molecular regulation was similar between UCP1 KO males and females, with an upregulation of serum FGF21, coinciding with beiging of inguinal white adipose tissue and induced lipid metabolism. While energy expenditure did not display significant differences, UCP1 KO females significantly increased their food intake. Altogether, our results indicate that hyperphagia is likely counteracting the beneficial effects of FGF21 in female mice. This underlines the importance of sex-specific studies in (pre)clinical research for personalized drug development.
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Affiliation(s)
- Marlou Klein Hazebroek
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Rutger Laterveer
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Maria Kutschke
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Vida Ramšak Marčeta
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Clarissa S Barthem
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden
| | - Susanne Keipert
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91, Stockholm, Sweden.
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13
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Tarantini S, Subramanian M, Butcher JT, Yabluchanskiy A, Li X, Miller RA, Balasubramanian P. Revisiting adipose thermogenesis for delaying aging and age-related diseases: Opportunities and challenges. Ageing Res Rev 2023; 87:101912. [PMID: 36924940 PMCID: PMC10164698 DOI: 10.1016/j.arr.2023.101912] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 03/03/2023] [Accepted: 03/13/2023] [Indexed: 03/17/2023]
Abstract
Adipose tissue undergoes significant changes in structure, composition, and function with age including altered adipokine secretion, decreased adipogenesis, altered immune cell profile and increased inflammation. Considering the role of adipose tissue in whole-body energy homeostasis, age-related dysfunction in adipose metabolism could potentially contribute to an increased risk for metabolic diseases and accelerate the onset of other age-related diseases. Increasing cellular energy expenditure in adipose tissue, also referred to as thermogenesis, has emerged as a promising strategy to improve adipose metabolism and treat obesity-related metabolic disorders. However, translating this strategy to the aged population comes with several challenges such as decreased thermogenic response and the paucity of safe pharmacological agents to activate thermogenesis. This mini-review aims to discuss the current body of knowledge on aging and thermogenesis and highlight the unexplored opportunities (cellular mechanisms and secreted factors) to target thermogenic mechanisms for delaying aging and age-related diseases. Finally, we also discuss the emerging role of thermogenic adipocytes in healthspan and lifespan extension.
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Affiliation(s)
- Stefano Tarantini
- Vascular Cognitive Impairment, Neurodegeneration and Healthy Brain Aging Program, Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Oklahoma Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Madhan Subramanian
- Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, USA
| | - Joshua T Butcher
- Department of Physiological Sciences, College of Veterinary Medicine, Oklahoma State University, Stillwater, OK, USA
| | - Andriy Yabluchanskiy
- Vascular Cognitive Impairment, Neurodegeneration and Healthy Brain Aging Program, Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Oklahoma Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Department of Health Promotion Sciences, College of Public Health, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA
| | - Xinna Li
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Richard A Miller
- Department of Pathology and Geriatrics Center, University of Michigan, Ann Arbor, MI, USA
| | - Priya Balasubramanian
- Vascular Cognitive Impairment, Neurodegeneration and Healthy Brain Aging Program, Department of Neurosurgery, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; Oklahoma Center for Geroscience and Healthy Brain Aging, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA; The Peggy and Charles Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, USA.
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14
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Rani R, Syngkli S, Nongkhlaw J, Das B. Expression and characterisation of human glycerol kinase: the role of solubilising agents and molecular chaperones. Biosci Rep 2023; 43:BSR20222258. [PMID: 37021775 PMCID: PMC10130975 DOI: 10.1042/bsr20222258] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Revised: 03/11/2023] [Accepted: 04/06/2023] [Indexed: 04/07/2023] Open
Abstract
BACKGROUND Glycerol kinase (GK; EC 2.7.1.30) facilitates the entry of glycerol into pathways of glucose and triglyceride metabolism and may play a potential role in Type 2 diabetes mellitus (T2DM). However, the detailed regulatory mechanisms and structure of the human GK are unknown. METHODS The human GK gene was cloned into the pET-24a(+) vector and over-expressed in Escherichia coli BL21 (DE3). Since the protein was expressed as inclusion bodies (IBs), various culture parameters and solubilising agents were used but they did not produce bioactive His-GK; however, co-expression of His-GK with molecular chaperones, specifically pKJE7, achieved expression of bioactive His-GK. The overexpressed bioactive His-GK was purified using coloumn chromatography and characterised using enzyme kinetics. RESULTS The overexpressed bioactive His-GK was purified apparently to homogeneity (∼295-fold) and characterised. The native His-GK was a dimer with a monomeric molecular weight of ∼55 kDa. Optimal enzyme activity was observed in TEA buffer (50 mM) at 7.5 pH. K+ (40 mM) and Mg2+ (2.0 mM) emerged as prefered metal ions for His-GK activity with specific activity 0.780 U/mg protein. The purified His-GK obeyed standard Michaelis-Menten kinetics with Km value of 5.022 µM (R2=0.927) for its substrate glycerol; whereas, that for ATP and PEP was 0.767 mM (R2=0.928) and 0.223 mM (R2=0.967), respectively. Other optimal parameters for the substrate and co-factors were also determined. CONCLUSION The present study demonstrates that co-expression of molecular chaperones assists with the expression of bioactive human GK for its characterisation.
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Affiliation(s)
- Riva Mary Rani
- Biological Chemistry Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
| | - Superior Syngkli
- Biological Chemistry Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
| | - Joplin Nongkhlaw
- Biological Chemistry Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
| | - Bidyadhar Das
- Biological Chemistry Laboratory, Department of Zoology, North-Eastern Hill University, Shillong 793022, India
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15
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Sharma AK, Wolfrum C. Lipid cycling isn't all futile. Nat Metab 2023; 5:540-541. [PMID: 37012497 DOI: 10.1038/s42255-023-00779-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
Affiliation(s)
- Anand Kumar Sharma
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
| | - Christian Wolfrum
- Laboratory of Translational Nutrition Biology, Institute of Food, Nutrition and Health, ETH Zurich, Zurich, Switzerland.
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16
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Raj RR, Lofquist S, Lee MJ. Remodeling of Adipose Tissues by Fatty Acids: Mechanistic Update on Browning and Thermogenesis by n-3 Polyunsaturated Fatty Acids. Pharm Res 2023; 40:467-480. [PMID: 36050546 DOI: 10.1007/s11095-022-03377-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2022] [Accepted: 08/18/2022] [Indexed: 11/24/2022]
Abstract
Enhancing thermogenesis by increasing the amount and activity of brown and brite adipocytes is a potential therapeutic target for obesity and its associated diseases. Diet plays important roles in energy metabolism and a myriad of dietary components including lipids are known to regulate thermogenesis through recruitment and activation of brown and brite adipocytes. Depending on types of fatty acids (FAs), the major constituent in lipids, their health benefits differ. Long-chain polyunsaturated FAs (PUFAs), especially n-3 PUFAs remodel adipose tissues in a healthier manner with reduced inflammation and enhanced thermogenesis, while saturated FAs exhibit contrasting effects. Lipid mediators derived from FAs act as autocrine/paracrine as well as endocrine factors to regulate thermogenesis. We discuss lipid mediators that may contribute to the differential effects of FAs on adipose tissue remodeling and hence, cardiometabolic diseases. We also discuss current understanding of molecular and cellular mechanisms through which n-3 PUFAs enhance thermogenesis. Elucidating molecular details of beneficial effects of n-3 PUFAs on thermogenesis is expected to provide information that can be used for development of novel therapeutics for obesity and its associated diseases.
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Affiliation(s)
- Radha Raman Raj
- Department of Human Nutrition, Food and Animal Sciences, University of Hawaii at Manoa, 1955 East West Road, Honolulu, HI, 98622, USA
| | - Sydney Lofquist
- Department of Human Nutrition, Food and Animal Sciences, University of Hawaii at Manoa, 1955 East West Road, Honolulu, HI, 98622, USA
| | - Mi-Jeong Lee
- Department of Human Nutrition, Food and Animal Sciences, University of Hawaii at Manoa, 1955 East West Road, Honolulu, HI, 98622, USA.
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17
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Abstract
Rather than serving as a mere onlooker, adipose tissue is a complex endocrine organ and active participant in disease initiation and progression. Disruptions of biological processes operating within adipose can disturb healthy systemic physiology, the sequelae of which include metabolic disorders such as obesity and type 2 diabetes. A burgeoning interest in the field of adipose research has allowed for the elucidation of regulatory networks underlying both adipose tissue function and dysfunction. Despite this progress, few diseases are treated by targeting maladaptation in the adipose, an oft-overlooked organ. In this review, we elaborate on the distinct subtypes of adipocytes, their developmental origins and secretory roles, and the dynamic interplay at work within the tissue itself. Central to this discussion is the relationship between adipose and disease states, including obesity, cachexia, and infectious diseases, as we aim to leverage our wealth of knowledge for the development of novel and targeted therapeutics.
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Affiliation(s)
- Christopher Auger
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA;
| | - Shingo Kajimura
- Division of Endocrinology, Diabetes and Metabolism, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA; .,Howard Hughes Medical Institute, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, Massachusetts, USA;
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18
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Takeda Y, Harada Y, Yoshikawa T, Dai P. Mitochondrial Energy Metabolism in the Regulation of Thermogenic Brown Fats and Human Metabolic Diseases. Int J Mol Sci 2023; 24:ijms24021352. [PMID: 36674862 PMCID: PMC9861294 DOI: 10.3390/ijms24021352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2022] [Revised: 01/06/2023] [Accepted: 01/09/2023] [Indexed: 01/13/2023] Open
Abstract
Brown fats specialize in thermogenesis by increasing the utilization of circulating blood glucose and fatty acids. Emerging evidence suggests that brown adipose tissue (BAT) prevents the incidence of obesity-associated metabolic diseases and several types of cancers in humans. Mitochondrial energy metabolism in brown/beige adipocytes regulates both uncoupling protein 1 (UCP1)-dependent and -independent thermogenesis for cold adaptation and the utilization of excess nutrients and energy. Many studies on the quantification of human BAT indicate that mass and activity are inversely correlated with the body mass index (BMI) and visceral adiposity. Repression is caused by obesity-associated positive and negative factors that control adipocyte browning, de novo adipogenesis, mitochondrial energy metabolism, UCP1 expression and activity, and noradrenergic response. Systemic and local factors whose levels vary between lean and obese conditions include growth factors, inflammatory cytokines, neurotransmitters, and metal ions such as selenium and iron. Modulation of obesity-associated repression in human brown fats is a promising strategy to counteract obesity and related metabolic diseases through the activation of thermogenic capacity. In this review, we highlight recent advances in mitochondrial metabolism, thermogenic regulation of brown fats, and human metabolic diseases.
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Affiliation(s)
- Yukimasa Takeda
- Department of Cellular Regenerative Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
- Correspondence: (Y.T.); (P.D.); Tel.: +81-75-251-5444 (Y.T.); +81-75-251-5135 (P.D.)
| | - Yoshinori Harada
- Department of Pathology and Cell Regulation, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
| | - Toshikazu Yoshikawa
- Department of Cellular Regenerative Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
- Louis Pasteur Center for Medical Research, 103-5 Tanaka-Monzen-cho, Sakyo-ku, Kyoto 606-8225, Japan
| | - Ping Dai
- Department of Cellular Regenerative Medicine, Graduate School of Medical Science, Kyoto Prefectural University of Medicine, 465 Kajii-cho, Kawaramachi-Hirokoji, Kamigyo-ku, Kyoto 602-8566, Japan
- Correspondence: (Y.T.); (P.D.); Tel.: +81-75-251-5444 (Y.T.); +81-75-251-5135 (P.D.)
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19
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Senn L, Costa AM, Avallone R, Socała K, Wlaź P, Biagini G. Is the peroxisome proliferator-activated receptor gamma a putative target for epilepsy treatment? Current evidence and future perspectives. Pharmacol Ther 2023; 241:108316. [PMID: 36436690 DOI: 10.1016/j.pharmthera.2022.108316] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/20/2022] [Accepted: 11/21/2022] [Indexed: 11/25/2022]
Abstract
The peroxisome proliferator-activated receptor gamma (PPARγ), which belongs to the family of nuclear receptors, has been mainly studied as an important factor in metabolic disorders. However, in recent years the potential role of PPARγ in different neurological diseases has been increasingly investigated. Especially, in the search of therapeutic targets for patients with epilepsy the question of the involvement of PPARγ in seizure control has been raised. Epilepsy is a chronic neurological disorder causing a major impact on the psychological, social, and economic conditions of patients and their families, besides the problems of the disease itself. Considering that the world prevalence of epilepsy ranges between 0.5% - 1.0%, this condition is the fourth for importance among the other neurological disorders, following migraine, stroke, and dementia. Among others, temporal lobe epilepsy (TLE) is the most common form of epilepsy in adult patients. About 65% of individuals who receive antiseizure medications (ASMs) experience seizure independence. For those in whom seizures still recur, investigating PPARγ could lead to the development of novel ASMs. This review focuses on the most important findings from recent investigations about the potential intracellular PPARγ-dependent processes behind different compounds that exhibited anti-seizure effects. Additionally, recent clinical investigations are discussed along with the promising results found for PPARγ agonists and the ketogenic diet (KD) in various rodent models of epilepsy.
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Affiliation(s)
- Lara Senn
- Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy; PhD School of Clinical and Experimental Medicine (CEM), University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Anna-Maria Costa
- Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Rossella Avallone
- Department of Life Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy
| | - Katarzyna Socała
- Department of Animal Physiology and Pharmacology, Institute of Biological Sciences, Maria Curie-Skłodowska University, PL 20-033 Lublin, Poland
| | - Piotr Wlaź
- Department of Animal Physiology and Pharmacology, Institute of Biological Sciences, Maria Curie-Skłodowska University, PL 20-033 Lublin, Poland
| | - Giuseppe Biagini
- Department of Biomedical, Metabolic, and Neural Sciences, University of Modena and Reggio Emilia, 41125 Modena, Italy.
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20
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Mishra S, Wang Z, Volk MJ, Zhao H. Design and application of a kinetic model of lipid metabolism in Saccharomyces cerevisiae. Metab Eng 2023; 75:12-18. [PMID: 36371031 DOI: 10.1016/j.ymben.2022.11.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2022] [Revised: 10/29/2022] [Accepted: 11/08/2022] [Indexed: 11/10/2022]
Abstract
Lipid biosynthesis plays a vital role in living cells and has been increasingly engineered to overproduce various lipid-based chemicals. However, owing to the tightly constrained and interconnected nature of lipid biosynthesis, both understanding and engineering of lipid metabolism remain challenging, even with the help of mathematical models. Here we report the development of a kinetic metabolic model of lipid metabolism in Saccharomyces cerevisiae that integrates fatty acid biosynthesis, glycerophospholipid metabolism, sphingolipid metabolism, storage lipids, lumped sterol synthesis, and the synthesis and transport of relevant target-chemicals, such as fatty acids and fatty alcohols. The model was trained on lipidomic data of a reference S. cerevisiae strain, single knockout mutants, and lipid overproduction strains reported in literature. The model was used to design mutants for fatty alcohol overproduction and the lipidomic analysis of the resultant mutant strains coupled with model-guided hypothesis led to discovery of a futile cycle in the triacylglycerol biosynthesis pathway. In addition, the model was used to explain successful and unsuccessful mutant designs in metabolic engineering literature. Thus, this kinetic model of lipid metabolism can not only enable the discovery of new phenomenon in lipid metabolism but also the engineering of mutant strains for overproduction of lipids.
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Affiliation(s)
- Shekhar Mishra
- Department of Chemical and Biomolecular Engineering, Department of Energy Center for Advanced Bioenergy and Bioproducts Innovation, Carl R. Woese Institute for Genomic Biology, USA
| | | | - Michael J Volk
- Department of Chemical and Biomolecular Engineering, Department of Energy Center for Advanced Bioenergy and Bioproducts Innovation, Carl R. Woese Institute for Genomic Biology, USA
| | - Huimin Zhao
- Department of Chemical and Biomolecular Engineering, Department of Energy Center for Advanced Bioenergy and Bioproducts Innovation, Carl R. Woese Institute for Genomic Biology, USA; Department of Biochemistry, USA; Departments of Chemistry and Bioengineering, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA.
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21
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Selenium and selenoproteins in thermogenic adipocytes. Arch Biochem Biophys 2022; 731:109445. [PMID: 36265651 PMCID: PMC9981474 DOI: 10.1016/j.abb.2022.109445] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2022] [Revised: 10/13/2022] [Accepted: 10/14/2022] [Indexed: 11/20/2022]
Abstract
Selenium (Se) is involved in energy metabolism in the liver, white adipose tissue, and skeletal muscle, and may also play a role in thermogenic adipocytes, i.e. brown and beige adipocytes. Thereby this micronutrient is a key nutritional target to aid in combating obesity and metabolic diseases. In thermogenic adipocytes, particularly in brown adipose tissue (BAT), the selenoprotein type 2 iodothyronine deiodinase (DIO2) is essential for the activation of adaptive thermogenesis. Recent evidence has suggested that additional selenoproteins may also be participating in this process, and a role for Se itself through its metabolic pathways is also envisioned. In this review, we discuss the recognized effects and the knowledge gaps in the involvement of Se metabolism and selenoproteins in the mechanisms of adaptive thermogenesis in thermogenic (brown and beige) adipocytes.
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22
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AlZaim I, Eid AH, Abd-Elrahman KS, El-Yazbi AF. Adipose Tissue Mitochondrial Dysfunction and Cardiometabolic Diseases: On the Search for Novel Molecular Targets. Biochem Pharmacol 2022; 206:115337. [DOI: 10.1016/j.bcp.2022.115337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2022] [Revised: 10/17/2022] [Accepted: 10/31/2022] [Indexed: 11/06/2022]
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23
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Nomiyama K, Yamamoto Y, Eguchi A, Nishikawa H, Mizukawa H, Yokoyama N, Ichii O, Takiguchi M, Nakayama SMM, Ikenaka Y, Ishizuka M. Health impact assessment of pet cats caused by organohalogen contaminants by serum metabolomics and thyroid hormone analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 842:156490. [PMID: 35667425 DOI: 10.1016/j.scitotenv.2022.156490] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2022] [Revised: 05/24/2022] [Accepted: 06/01/2022] [Indexed: 06/15/2023]
Abstract
Companion animals are in close contact with the human surroundings, and there is growing concern about the effects of harmful substances on the health of pet cats. In this study, we investigated the potential health effects of organohalogen compounds (OHCs) on thyroid hormone (TH) homeostasis and metabolomics in Japanese pet cats. There was a significant negative correlation between concentrations of several contaminants, such as polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), hydroxylated PCBs (OH-PCBs), hydroxylated PBDEs (OH-PBDEs), and THs in cat serum samples. These results suggested that exposure to OHCs causes a decrease in serum TH levels in pet cats. In this metabolomics study, each exposure level of parent compounds (PCBs and PBDEs) and their hydroxylated compounds (OH-PCBs and OH-PBDEs) were associated with their own unique primary metabolic pathways, suggesting that parent and phenolic compounds exhibit different mechanisms of action and biological effects. PCBs were associated with many metabolic pathways, including glutathione and purine metabolism, and the effects were replicated in in-vivo cat PCB administration studies. These results demonstrated that OHC exposure causes chronic oxidative stress in pet cats. PBDEs were positively associated with alanine, aspartate, and glutamate metabolism. Due to the chronic exposure of cats to mixtures of these contaminants, the combination of their respective metabolic pathways may have a synergistic effect.
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Affiliation(s)
- Kei Nomiyama
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan.
| | - Yasuo Yamamoto
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan
| | - Akifumi Eguchi
- Center for Preventive Medical Sciences, Chiba University, Inage-ku Yayoi-cho 1-33, Chiba-city 263-8522, Japan
| | - Hiroyuki Nishikawa
- Center for Marine Environmental Studies (CMES), Ehime University, Bunkyo-cho 2-5, Matsuyama, Ehime 790-8577, Japan
| | - Hazuki Mizukawa
- Department of Science and Technology for Biological Resources and Environment, Graduate School of Agriculture, Ehime University, Tarumi 3-5-7, Matsuyama, Ehime 790-8566, Japan
| | - Nozomu Yokoyama
- Veterinary Teaching Hospital, Graduate School of Veterinary Medicine, Hokkaido University, N18 W9, Sapporo, Hokkaido 060-0818, Japan
| | - Osamu Ichii
- Department of Basic Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Mitsuyoshi Takiguchi
- Laboratory of Veterinary Internal Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Shouta M M Nakayama
- Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
| | - Yoshinori Ikenaka
- Veterinary Teaching Hospital, Graduate School of Veterinary Medicine, Hokkaido University, N18 W9, Sapporo, Hokkaido 060-0818, Japan; Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan; Water Research Group, Unit for Environmental Sciences and Management, North-West University, Potchefstroom Campus, X6001, Potchefstroom 2520, South Africa; One Health Research Center, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo 060-0818, Japan
| | - Mayumi Ishizuka
- Department of Environmental Veterinary Sciences, Faculty of Veterinary Medicine, Hokkaido University, Kita 18, Nishi 9, Kita-ku, Sapporo, Hokkaido 060-0818, Japan
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Assis AP, Silva KE, Lautherbach N, Morgan HJN, Garófalo MAR, Zanon NM, Navegantes LCC, Chaves VE, Kettelhut IDC. Glucocorticoids decrease thermogenic capacity and increase triacylglycerol synthesis by glycerokinase activation in the brown adipose tissue of rats. Lipids 2022; 57:313-325. [PMID: 36098349 DOI: 10.1002/lipd.12358] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Revised: 08/03/2022] [Accepted: 08/28/2022] [Indexed: 11/11/2022]
Abstract
Although it is well established that glucocorticoids inactivate thermogenesis and promote lipid accumulation in interscapular brown adipose tissue (IBAT), the underlying mechanisms remain unknown. We found that dexamethasone treatment (1 mg/kg) for 7 days in rats decreased the IBAT thermogenic activity, evidenced by its lower responsiveness to noradrenaline injection associated with reduced content of mitochondrial proteins, respiratory chain protein complexes, noradrenaline, and the β3 -adrenergic receptor. In parallel, to understand better how dexamethasone increases IBAT lipid content, we also investigated the activity of the ATP citrate lyase (ACL), a key enzyme of de novo fatty acid synthesis, glucose-6-phosphate dehydrogenase (G6PD), a rate-limiting enzyme of the pentose phosphate pathway, and the three glycerol-3-P generating pathways: (1) glycolysis, estimated by 2-deoxyglucose uptake, (2) glyceroneogenesis, evaluated by phosphoenolpyruvate carboxykinase activity and pyruvate incorporation into triacylglycerol-glycerol, and (3) direct phosphorylation of glycerol, investigated by the content and activity of glycerokinase. Dexamethasone increased the mass and the lipid content of IBAT as well as plasma levels of glucose, insulin, non-esterified fatty acid, and glycerol. Furthermore, dexamethasone increased ACL and G6PD activities (79% and 48%, respectively). Despite promoting a decrease in the incorporation of U-[14 C]-glycerol into triacylglycerol (~54%), dexamethasone increased the content (~55%) and activity (~41%) of glycerokinase without affecting glucose uptake or glyceroneogenesis. Our data suggest that glucocorticoid administration reduces IBAT thermogenesis through sympathetic inactivation and stimulates glycerokinase activity and content, contributing to increased generation of glycerol-3-P, which is mostly used to esterify fatty acid and increase triacylglycerol content promoting IBAT whitening.
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Affiliation(s)
- Ana Paula Assis
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Karine Emanuelle Silva
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | - Natalia Lautherbach
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | | | | | - Neusa Maria Zanon
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
| | | | | | - Isis do Carmo Kettelhut
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil
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Silva GDN, Amato AA. Thermogenic adipose tissue aging: Mechanisms and implications. Front Cell Dev Biol 2022; 10:955612. [PMID: 35979379 PMCID: PMC9376969 DOI: 10.3389/fcell.2022.955612] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2022] [Accepted: 07/04/2022] [Indexed: 12/27/2022] Open
Abstract
Adipose tissue undergoes significant anatomical and functional changes with aging, leading to an increased risk of metabolic diseases. Age-related changes in adipose tissue include overall defective adipogenesis, dysfunctional adipokine secretion, inflammation, and impaired ability to produce heat by nonshivering thermogenesis. Thermogenesis in adipose tissue is accomplished by brown and beige adipocytes, which also play a role in regulating energy homeostasis. Brown adipocytes develop prenatally, are found in dedicated depots, and involute in early infancy in humans. In contrast, beige adipocytes arise postnatally in white adipose tissue and persist throughout life, despite being lost with aging. In recent years, there have been significant advances in the understanding of age-related reduction in thermogenic adipocyte mass and function. Mechanisms underlying such changes are beginning to be delineated. They comprise diminished adipose precursor cell pool size and adipogenic potential, mitochondrial dysfunction, decreased sympathetic signaling, and altered paracrine and endocrine signals. This review presents current evidence from animal models and human studies for the mechanisms underlying thermogenic adipocyte loss and discusses potential strategies targeting brown and beige adipocytes to increase health span and longevity.
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Special Issue: Emerging Paradigms in Insulin Resistance. Biomedicines 2022; 10:biomedicines10071471. [PMID: 35884776 PMCID: PMC9313343 DOI: 10.3390/biomedicines10071471] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Accepted: 06/17/2022] [Indexed: 11/16/2022] Open
Abstract
This Biomedicines Special Issue was designed to attract articles that focused on different facets of biology relating to insulin resistance, defined as reduced cellular and organismal response to the insulin hormone, and its underlying mechanisms [...]
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27
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Oeckl J, Janovska P, Adamcova K, Bardova K, Brunner S, Dieckmann S, Ecker J, Fromme T, Funda J, Gantert T, Giansanti P, Hidrobo MS, Kuda O, Kuster B, Li Y, Pohl R, Schmitt S, Schweizer S, Zischka H, Zouhar P, Kopecky J, Klingenspor M. Loss of UCP1 function augments recruitment of futile lipid cycling for thermogenesis in murine brown fat. Mol Metab 2022; 61:101499. [PMID: 35470094 PMCID: PMC9097615 DOI: 10.1016/j.molmet.2022.101499] [Citation(s) in RCA: 34] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 04/12/2022] [Accepted: 04/12/2022] [Indexed: 11/30/2022] Open
Affiliation(s)
- Josef Oeckl
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Petra Janovska
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Katerina Adamcova
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Kristina Bardova
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Sarah Brunner
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Sebastian Dieckmann
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Josef Ecker
- ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Tobias Fromme
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Jiri Funda
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Thomas Gantert
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Piero Giansanti
- Chair of Proteomics and Bioanalytics, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; Bavarian Center for Biomolecular Mass Spectrometry, Technical University of Munich, Freising, Germany
| | - Maria Soledad Hidrobo
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Ondrej Kuda
- Laboratory of Metabolism of Bioactive Lipids, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Bernhard Kuster
- Chair of Proteomics and Bioanalytics, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; Bavarian Center for Biomolecular Mass Spectrometry, Technical University of Munich, Freising, Germany
| | - Yongguo Li
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Radek Pohl
- NMR spectroscopy, Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences, Czech Republic
| | - Sabine Schmitt
- Institute of Toxicology and Environmental Hygiene, School of Medicine, Technical University of Munich, Munich, Germany
| | - Sabine Schweizer
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany
| | - Hans Zischka
- Institute of Toxicology and Environmental Hygiene, School of Medicine, Technical University of Munich, Munich, Germany; Institute of Molecular Toxicology and Pharmacology, Helmholtz Center Munich, Munich, Germany
| | - Petr Zouhar
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic
| | - Jan Kopecky
- Laboratory of Adipose Tissue Biology, Institute of Physiology of the Czech Academy of Sciences, Czech Republic.
| | - Martin Klingenspor
- Chair for Molecular Nutritional Medicine, TUM School of Life Sciences, Technical University of Munich, Freising, Germany; EKFZ - Else Kröner Fresenius Center for Nutritional Medicine, Technical University of Munich, Freising, Germany; ZIEL Institute for Food & Health, Technical University of Munich, Freising, Germany.
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28
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Chen L, You Q, Liu M, Li S, Wu Z, Hu J, Ma Y, Xia L, Zhou Y, Xu N, Zhang S. Remodeling of dermal adipose tissue alleviates cutaneous toxicity induced by anti-EGFR therapy. eLife 2022; 11:72443. [PMID: 35324426 PMCID: PMC8947768 DOI: 10.7554/elife.72443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Accepted: 03/14/2022] [Indexed: 12/12/2022] Open
Abstract
Anti-epidermal growth factor receptor (EGFR) therapy–associated cutaneous toxicity is a syndrome characterized by papulopustular rash, local inflammation, folliculitis, and microbial infection, resulting in a decrease in quality of life and dose interruption. However, no effective clinical intervention is available for this adverse effect. Here, we report the atrophy of dermal white adipose tissue (dWAT), a highly plastic adipose tissue with various skin-specific functions, correlates with rash occurrence and exacerbation in a murine model of EGFR inhibitor-induced rash. The reduction in dWAT is due to the inhibition of adipogenic differentiation by defects in peroxisome proliferator-activated receptor γ (PPARγ) signaling, and increased lipolysis by the induced expression of the lipolytic cytokine IL6. The activation of PPARγ by rosiglitazone maintains adipogenic differentiation and represses the transcription of IL6, eventually improving skin functions and ameliorating the severity of rash without altering the antitumor effects. Thus, activation of PPARγ represents a promising approach to ameliorate cutaneous toxicity in patients with cancer who receive anti-EGFR therapy.
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Affiliation(s)
- Leying Chen
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Qing You
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Min Liu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Shuaihu Li
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Zhaoyu Wu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Jiajun Hu
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Yurui Ma
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Liangyong Xia
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Ying Zhou
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
| | - Nan Xu
- Department of Dermatology, Shanghai East Hospital, Tongji University, Shanghai, China
| | - Shiyi Zhang
- School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China
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29
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Hu W, Jiang C, Kim M, Xiao Y, Richter HJ, Guan D, Zhu K, Krusen BM, Roberts AN, Miller J, Steger DJ, Lazar MA. Isoform-specific functions of PPARγ in gene regulation and metabolism. Genes Dev 2022; 36:300-312. [PMID: 35273075 PMCID: PMC8973844 DOI: 10.1101/gad.349232.121] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 02/15/2022] [Indexed: 12/12/2022]
Abstract
In this study, Hu et al. investigated the specific functions of the two main PPARγ isoforms by generating mouse lines in which endogenous PPARγ1 and PPARγ2 were epitope-tagged to interrogate isoform-specific genomic binding, and mice deficient in either PPARγ1 or PPARγ2 to assess isoform-specific gene regulation. They show that PPARγ isoforms have specific and separable metabolic functions that may be targeted to improve therapy for insulin resistance and diabetes. Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor that is a vital regulator of adipogenesis, insulin sensitivity, and lipid metabolism. Activation of PPARγ by antidiabetic thiazolidinediones (TZD) reverses insulin resistance but also leads to weight gain that limits the use of these drugs. There are two main PPARγ isoforms, but the specific functions of each are not established. Here we generated mouse lines in which endogenous PPARγ1 and PPARγ2 were epitope-tagged to interrogate isoform-specific genomic binding, and mice deficient in either PPARγ1 or PPARγ2 to assess isoform-specific gene regulation. Strikingly, although PPARγ1 and PPARγ2 contain identical DNA binding domains, we uncovered isoform-specific genomic binding sites in addition to shared sites. Moreover, PPARγ1 and PPARγ2 regulated a different set of genes in adipose tissue depots, suggesting distinct roles in adipocyte biology. Indeed, mice with selective deficiency of PPARγ1 maintained body temperature better than wild-type or PPARγ2-deficient mice. Most remarkably, although TZD treatment improved glucose tolerance in mice lacking either PPARγ1 or PPARγ2, the PPARγ1-deficient mice were protected from TZD-induced body weight gain compared with PPARγ2-deficient mice. Thus, PPARγ isoforms have specific and separable metabolic functions that may be targeted to improve therapy for insulin resistance and diabetes.
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Affiliation(s)
- Wenxiang Hu
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Chunjie Jiang
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Mindy Kim
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Yang Xiao
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Hannah J Richter
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Dongyin Guan
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Division of Diabetes, Endocrinology, and Metabolism, Department of Medicine, Baylor College of Medicine, Houston, Texas 77030, USA
| | - Kun Zhu
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Brianna M Krusen
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Arielle N Roberts
- Philadelphia College of Osteopathic Medicine, Philadelphia, Pennsylvania 19131, USA
| | - Jessica Miller
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - David J Steger
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Mitchell A Lazar
- Institute for Diabetes, Obesity, and Metabolism, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.,Division of Endocrinology, Diabetes, and Metabolism, Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania 19104, USA
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30
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Brownstein AJ, Veliova M, Acin-Perez R, Liesa M, Shirihai OS. ATP-consuming futile cycles as energy dissipating mechanisms to counteract obesity. Rev Endocr Metab Disord 2022; 23:121-131. [PMID: 34741717 PMCID: PMC8873062 DOI: 10.1007/s11154-021-09690-w] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 09/24/2021] [Indexed: 12/25/2022]
Abstract
Obesity results from an imbalance in energy homeostasis, whereby excessive energy intake exceeds caloric expenditure. Energy can be dissipated out of an organism by producing heat (thermogenesis), explaining the long-standing interest in exploiting thermogenic processes to counteract obesity. Mitochondrial uncoupling is a process that expends energy by oxidizing nutrients to produce heat, instead of ATP synthesis. Energy can also be dissipated through mechanisms that do not involve mitochondrial uncoupling. Such mechanisms include futile cycles described as metabolic reactions that consume ATP to produce a product from a substrate but then converting the product back into the original substrate, releasing the energy as heat. Energy dissipation driven by cellular ATP demand can be regulated by adjusting the speed and number of futile cycles. Energy consuming futile cycles that are reviewed here are lipolysis/fatty acid re-esterification cycle, creatine/phosphocreatine cycle, and the SERCA-mediated calcium import and export cycle. Their reliance on ATP emphasizes that mitochondrial oxidative function coupled to ATP synthesis, and not just uncoupling, can play a role in thermogenic energy dissipation. Here, we review ATP consuming futile cycles, the evidence for their function in humans, and their potential employment as a strategy to dissipate energy and counteract obesity.
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Affiliation(s)
- Alexandra J Brownstein
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Molecular Cellular Integrative Physiology Interdepartmental Program, University of California, Los Angeles, CA, 90095, USA
| | - Michaela Veliova
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Rebeca Acin-Perez
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
| | - Marc Liesa
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Molecular Cellular Integrative Physiology Interdepartmental Program, University of California, Los Angeles, CA, 90095, USA
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA
- Molecular Biology Institute, University of California, Los Angeles, CA, 90095, USA
| | - Orian S Shirihai
- Metabolism Theme, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
- Molecular Cellular Integrative Physiology Interdepartmental Program, University of California, Los Angeles, CA, 90095, USA.
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
- Department of Medicine, Division of Endocrinology, David Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
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31
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Jankauskas SS, Kansakar U, Varzideh F, Wilson S, Mone P, Lombardi A, Gambardella J, Santulli G. Heart failure in diabetes. Metabolism 2021; 125:154910. [PMID: 34627874 PMCID: PMC8941799 DOI: 10.1016/j.metabol.2021.154910] [Citation(s) in RCA: 86] [Impact Index Per Article: 28.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2021] [Revised: 10/02/2021] [Accepted: 10/04/2021] [Indexed: 12/16/2022]
Abstract
Heart failure and cardiovascular disorders represent the leading cause of death in diabetic patients. Here we present a systematic review of the main mechanisms underlying the development of diabetic cardiomyopathy. We also provide an excursus on the relative contribution of cardiomyocytes, fibroblasts, endothelial and smooth muscle cells to the pathophysiology of heart failure in diabetes. After having described the preclinical tools currently available to dissect the mechanisms of this complex disease, we conclude with a section on the most recent updates of the literature on clinical management.
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Affiliation(s)
- Stanislovas S Jankauskas
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA; Department of Molecular Pharmacology, Einstein Institute for Neuroimmunology and Inflammation, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Urna Kansakar
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA; Department of Molecular Pharmacology, Einstein Institute for Neuroimmunology and Inflammation, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Fahimeh Varzideh
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA; Department of Molecular Pharmacology, Einstein Institute for Neuroimmunology and Inflammation, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Scott Wilson
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Pasquale Mone
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Angela Lombardi
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA
| | - Jessica Gambardella
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA; Department of Molecular Pharmacology, Einstein Institute for Neuroimmunology and Inflammation, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, New York, NY 10461, USA; International Translational Research and Medical Education (ITME), Department of Advanced Biomedical Science, "Federico II" University, 80131 Naples, Italy
| | - Gaetano Santulli
- Department of Medicine, Fleischer Institute for Diabetes and Metabolism (FIDAM), Einstein-Mount Sinai Diabetes Research Center (ES-DRC), Albert Einstein College of Medicine, New York, NY 10461, USA; Department of Molecular Pharmacology, Einstein Institute for Neuroimmunology and Inflammation, Wilf Family Cardiovascular Research Institute, Einstein Institute for Aging Research, Albert Einstein College of Medicine, New York, NY 10461, USA; International Translational Research and Medical Education (ITME), Department of Advanced Biomedical Science, "Federico II" University, 80131 Naples, Italy.
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32
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Resident and migratory adipose immune cells control systemic metabolism and thermogenesis. Cell Mol Immunol 2021; 19:421-431. [PMID: 34837070 PMCID: PMC8891307 DOI: 10.1038/s41423-021-00804-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/28/2021] [Indexed: 02/08/2023] Open
Abstract
Glucose is a vital source of energy for all mammals. The balance between glucose uptake, metabolism and storage determines the energy status of an individual, and perturbations in this balance can lead to metabolic diseases. The maintenance of organismal glucose metabolism is a complex process that involves multiple tissues, including adipose tissue, which is an endocrine and energy storage organ that is critical for the regulation of systemic metabolism. Adipose tissue consists of an array of different cell types, including specialized adipocytes and stromal and endothelial cells. In addition, adipose tissue harbors a wide range of immune cells that play vital roles in adipose tissue homeostasis and function. These cells contribute to the regulation of systemic metabolism by modulating the inflammatory tone of adipose tissue, which is directly linked to insulin sensitivity and signaling. Furthermore, these cells affect the control of thermogenesis. While lean adipose tissue is rich in type 2 and anti-inflammatory cytokines such as IL-10, obesity tips the balance in favor of a proinflammatory milieu, leading to the development of insulin resistance and the dysregulation of systemic metabolism. Notably, anti-inflammatory immune cells, including regulatory T cells and innate lymphocytes, protect against insulin resistance and have the characteristics of tissue-resident cells, while proinflammatory immune cells are recruited from the circulation to obese adipose tissue. Here, we review the key findings that have shaped our understanding of how immune cells regulate adipose tissue homeostasis to control organismal metabolism.
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Pioglitazone Reverses Markers of Islet Beta-Cell De-Differentiation in db/db Mice While Modulating Expression of Genes Controlling Inflammation and Browning in White Adipose Tissue from Insulin-Resistant Mice and Humans. Biomedicines 2021; 9:biomedicines9091189. [PMID: 34572374 PMCID: PMC8470788 DOI: 10.3390/biomedicines9091189] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2021] [Revised: 08/21/2021] [Accepted: 09/02/2021] [Indexed: 12/12/2022] Open
Abstract
Obesity, insulin resistance, and type 2 diabetes contribute to increased morbidity and mortality in humans. The db/db mouse is an important mouse model that displays many key features of the human disease. Herein, we used the drug pioglitazone, a thiazolidinedione with insulin-sensitizing properties, to investigate blood glucose levels, indicators of islet β-cell health and maturity, and gene expression in adipose tissue. Oral administration of pioglitazone lowered blood glucose levels in db/db mice with a corresponding increase in respiratory quotient, which indicates improved whole-body carbohydrate utilization. In addition, white adipose tissue from db/db mice and from humans treated with pioglitazone showed increased expression of glycerol kinase. Both db/db mice and humans given pioglitazone displayed increased expression of UCP-1, a marker typically associated with brown adipose tissue. Moreover, pancreatic β-cells from db/db mice treated with pioglitazone had greater expression of insulin and Nkx6.1 as well as reduced abundance of the de-differentiation marker Aldh1a3. Collectively, these findings indicate that four weeks of pioglitazone therapy improved overall metabolic health in db/db mice. Our data are consistent with published reports of human subjects administered pioglitazone and with analysis of human adipose tissue taken from subjects treated with pioglitazone. In conclusion, the current study provides evidence that pioglitazone restores key markers of metabolic health and also showcases the utility of the db/db mouse to understand mechanisms associated with human metabolic disease and interventions that provide therapeutic benefit.
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Abstract
Brown and beige adipocytes are mitochondria-enriched cells capable of dissipating energy in the form of heat. These thermogenic fat cells were originally considered to function solely in heat generation through the action of the mitochondrial protein uncoupling protein 1 (UCP1). In recent years, significant advances have been made in our understanding of the ontogeny, bioenergetics and physiological functions of thermogenic fat. Distinct subtypes of thermogenic adipocytes have been identified with unique developmental origins, which have been increasingly dissected in cellular and molecular detail. Moreover, several UCP1-independent thermogenic mechanisms have been described, expanding the role of these cells in energy homeostasis. Recent studies have also delineated roles for these cells beyond the regulation of thermogenesis, including as dynamic secretory cells and as a metabolic sink. This Review presents our current understanding of thermogenic adipocytes with an emphasis on their development, biological functions and roles in systemic physiology.
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Morigny P, Boucher J, Arner P, Langin D. Lipid and glucose metabolism in white adipocytes: pathways, dysfunction and therapeutics. Nat Rev Endocrinol 2021; 17:276-295. [PMID: 33627836 DOI: 10.1038/s41574-021-00471-8] [Citation(s) in RCA: 185] [Impact Index Per Article: 61.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 01/15/2021] [Indexed: 12/14/2022]
Abstract
In mammals, the white adipocyte is a cell type that is specialized for storage of energy (in the form of triacylglycerols) and for energy mobilization (as fatty acids). White adipocyte metabolism confers an essential role to adipose tissue in whole-body homeostasis. Dysfunction in white adipocyte metabolism is a cardinal event in the development of insulin resistance and associated disorders. This Review focuses on our current understanding of lipid and glucose metabolic pathways in the white adipocyte. We survey recent advances in humans on the importance of adipocyte hypertrophy and on the in vivo turnover of adipocytes and stored lipids. At the molecular level, the identification of novel regulators and of the interplay between metabolic pathways explains the fine-tuning between the anabolic and catabolic fates of fatty acids and glucose in different physiological states. We also examine the metabolic alterations involved in the genesis of obesity-associated metabolic disorders, lipodystrophic states, cancers and cancer-associated cachexia. New challenges include defining the heterogeneity of white adipocytes in different anatomical locations throughout the lifespan and investigating the importance of rhythmic processes. Targeting white fat metabolism offers opportunities for improved patient stratification and a wide, yet unexploited, range of therapeutic opportunities.
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Affiliation(s)
- Pauline Morigny
- Institute of Metabolic and Cardiovascular Diseases (I2MC), Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1297, Toulouse, France
- University of Toulouse, Paul Sabatier University, I2MC, UMR1297, Toulouse, France
- Institute for Diabetes and Cancer, Helmholtz Center Munich, Neuherberg, Germany
- Joint Heidelberg-IDC Translational Diabetes Program, Inner Medicine 1, Heidelberg University Hospital, Heidelberg, Germany
- German Center for Diabetes Research (DZD), Neuherberg, Germany
| | - Jeremie Boucher
- Bioscience Metabolism, Research and Early Development, Cardiovascular, Renal and Metabolism (CVRM), BioPharmaceuticals R&D, AstraZeneca, Gothenburg, Sweden
- The Lundberg Laboratory for Diabetes Research, University of Gothenburg, Gothenburg, Sweden
- Wallenberg Centre for Molecular and Translational Medicine, University of Gothenburg, Gothenburg, Sweden
| | - Peter Arner
- Department of Medicine (H7), Karolinska Institutet, Stockholm, Sweden
| | - Dominique Langin
- Institute of Metabolic and Cardiovascular Diseases (I2MC), Institut National de la Santé et de la Recherche Médicale (Inserm), UMR1297, Toulouse, France.
- University of Toulouse, Paul Sabatier University, I2MC, UMR1297, Toulouse, France.
- Franco-Czech Laboratory for Clinical Research on Obesity, Third Faculty of Medicine, Prague and Paul Sabatier University, Toulouse, France.
- Toulouse University Hospitals, Laboratory of Clinical Biochemistry, Toulouse, France.
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Guan D, Sun H, Wang J, Wang Z, Li Y, Han H, Li X, Fang T. Rosiglitazone promotes glucose metabolism of GIFT tilapia based on the PI3K/Akt signaling pathway. Physiol Rep 2021; 9:e14765. [PMID: 33650786 PMCID: PMC7923568 DOI: 10.14814/phy2.14765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2020] [Revised: 01/28/2021] [Accepted: 01/30/2021] [Indexed: 11/24/2022] Open
Abstract
The study aimed to explore the effects of rosiglitazone on glucose metabolism of GIFT tilapia based on the PI3K/Akt signaling pathway. The experiment was divided into five groups: normal starch group (32%, LC), high starch group (53%, HC), high starch +rosiglitazone group 1 (10 mg/kg, R1), high starch + rosiglitazone group 2 (20 mg/kg, R2), and high starch + rosiglitazone group 3 (30 mg/kg, R3). The results showed that a high starch diet supplemented with 10-20 mg/kg rosiglitazone had a better specific growth rate and protein efficiency that was beneficial for the growth of the tilapia. Rosiglitazone had no significant effect on the contents of crude lipid, crude protein, crude ash, and moisture of the whole fish body (p > 0.05). The contents of triglycerides and total cholesterol in the R1, R2, and R3 groups were lower than those in the HC group. The levels of glutamic oxaloacetic transaminase (GOT) and glutamic pyruvic transaminase (GPT) in R1 and R2 groups were significantly lower than those in the HC groups (p < 0.05). However, the GOT and GPT levels in the R3 groups were significantly higher than those in the R1 and R2 groups (p < 0.05). With an increase in the rosiglitazone concentration, the contents of serum glucose, insulin, and hepatic glycogen in the R1, R2, and R3 groups decreased gradually. Meanwhile, the muscle glycogen content in the R1, R2, and R3 groups increased gradually. The mRNA expression of the IRS-1, PI3K, GLUT-4, and Akt proteins in the R1, R2, and R3 groups was significantly higher than that in the HC group (p < 0.05). Compared with the HC group, the expression of the GSK-3 mRNA in the R1, R2, and R3 groups was significantly reduced (p < 0.05). The protein expression of p-Akt in the R1 and R2 groups was higher than that in the HC group (p > 0.05). The protein expression of p-GSK-3β in the R1 and R2 groups was significantly higher than that in the HC group (p < 0.05). In conclusion, a high starch diet supplemented with rosiglitazone can improve growth, enhance the serum biochemical indices, and increase the muscle glycogen content in the GIFT tilapia. It benefits in upregulating the IRS-1, PI3K, and GLUT-4 mRNA levels in the skeletal muscle and promotes glucose uptake. Meanwhile, the phosphorylation of Akt and GSK-3β increased significantly and resulted in the inactivation of GSK-3β and alleviation of insulin resistance.
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Affiliation(s)
- Dong‐Yan Guan
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Hui‐Wen Sun
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Ji‐Ting Wang
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Zhen Wang
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Yang Li
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Hao‐Jun Han
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Xiang Li
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
| | - Ting‐Ting Fang
- Shandong Provincial Key Lab. of Animal Biotechnology and Disease Control and PreventionLab of Aquatic Animal Nutrition & Environmental HealthShandong Agricultural UniversityTaian CityShandong ProvinceChina
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Poursharifi P, Attané C, Mugabo Y, Al-Mass A, Ghosh A, Schmitt C, Zhao S, Guida J, Lussier R, Erb H, Chenier I, Peyot ML, Joly E, Noll C, Carpentier AC, Madiraju SRM, Prentki M. Adipose ABHD6 regulates tolerance to cold and thermogenic programs. JCI Insight 2020; 5:140294. [PMID: 33201859 PMCID: PMC7819748 DOI: 10.1172/jci.insight.140294] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2020] [Accepted: 11/11/2020] [Indexed: 12/31/2022] Open
Abstract
Enhanced energy expenditure in brown (BAT) and white adipose tissues (WAT) can be therapeutic against metabolic diseases. We examined the thermogenic role of adipose α/β-hydrolase domain 6 (ABHD6), which hydrolyzes monoacylglycerol (MAG), by employing adipose-specific ABHD6-KO mice. Control and KO mice showed similar phenotypes at room temperature and thermoneutral conditions. However, KO mice were resistant to hypothermia, which can be accounted for by the simultaneously increased lipolysis and lipogenesis of the thermogenic glycerolipid/free fatty acid (GL/FFA) cycle in visceral fat, despite unaltered uncoupling protein 1 expression. Upon cold stress, nuclear 2-MAG levels increased in visceral WAT of the KO mice. Evidence is provided that 2-MAG causes activation of PPARα in white adipocytes, leading to elevated expression and activity of GL/FFA cycle enzymes. In the ABHD6-ablated BAT, glucose and oxidative metabolism were elevated upon cold induction, without changes in GL/FFA cycle and lipid turnover. Moreover, response to in vivo β3-adrenergic stimulation was comparable between KO and control mice. Our data reveal a MAG/PPARα/GL/FFA cycling metabolic signaling network in visceral adipose tissue, which contributes to cold tolerance, and that adipose ABHD6 is a negative modulator of adaptive thermogenesis. Visceral adipose adipose α/β-hydrolase domain 6 regulates cold adaptation and acts as a brake for heat production via the regulation of thermogenic glycerolipid/free fatty acid cycling.
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Affiliation(s)
- Pegah Poursharifi
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Camille Attané
- Institut de Pharmacologie et de Biologie Structurale, Université de Toulouse, CNRS, UPS, Toulouse, France
| | - Yves Mugabo
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Anfal Al-Mass
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada.,Department of Medicine, McGill University, Montréal, Québec, Canada
| | - Anindya Ghosh
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Clémence Schmitt
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Shangang Zhao
- Touchstone Diabetes Center, UT Southwestern Medical Center, Dallas, Texas, USA
| | - Julian Guida
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Roxane Lussier
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Heidi Erb
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Isabelle Chenier
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Marie-Line Peyot
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Erik Joly
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Christophe Noll
- Division of Endocrinology, Department of Medicine, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - André C Carpentier
- Division of Endocrinology, Department of Medicine, Centre de recherche du Centre Hospitalier Universitaire de Sherbrooke, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - S R Murthy Madiraju
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
| | - Marc Prentki
- Departments of Nutrition, Biochemistry, and Molecular Medicine, University of Montreal, and Montreal Diabetes Research Center, Centre de Recherche du Centre Hospitalier de l'Université de Montréal (CRCHUM), Montréal, Québec, Canada
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Townsend LK, Brunetta HS, Mori MAS. Mitochondria-associated ER membranes in glucose homeostasis and insulin resistance. Am J Physiol Endocrinol Metab 2020; 319:E1053-E1060. [PMID: 32985254 DOI: 10.1152/ajpendo.00271.2020] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Obesity and insulin resistance (IR) are associated with endoplasmic reticulum (ER) stress and mitochondrial dysfunction in several tissues. Although for many years mitochondrial and ER function were studied separately, these organelles also connect to produce interdependent functions. Communication occurs at mitochondria-associated ER membranes (MAMs) and regulates lipid and calcium homeostasis, apoptosis, and the exchange of adenine nucleotides, among other things. Recent evidence suggests that MAMs contribute to organelle, cellular, and systemic metabolism. In obesity and IR models, metabolic tissues such as the liver, skeletal muscle, pancreas, and adipose tissue present alterations in MAM structure or function. The purpose of this mini review is to highlight the MAM disruptions that occur in each tissue during obesity and IR and its relationship with glucose homeostasis and IR. We also discuss the current controversy that surrounds MAMs' role in the development of IR.
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Affiliation(s)
- Logan K Townsend
- Department of Human Health and Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - Henver S Brunetta
- Department of Physiological Sciences, Federal University of Santa Catarina, Florianopolis, Brazil
- Department of Biochemistry and Tissue Biology, University of Campinas, Campinas, Brazil
| | - Marcelo A S Mori
- Department of Biochemistry and Tissue Biology, University of Campinas, Campinas, Brazil
- Obesity and Comorbidities Research Center, University of Campinas, Campinas, Brazil
- Experimental Medicine Research Cluster, University of Campinas, Campinas, Brazil
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Tam BT, Murphy J, Khor N, Morais JA, Santosa S. Acetyl-CoA Regulation, OXPHOS Integrity and Leptin Levels Are Different in Females With Childhood vs Adulthood Onset of Obesity. Endocrinology 2020; 161:5893756. [PMID: 32808657 DOI: 10.1210/endocr/bqaa142] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 08/10/2020] [Indexed: 01/12/2023]
Abstract
Although childhood-onset obesity (CO) and adulthood-onset obesity (AO) are known to lead to distinctive clinical manifestations and disease risks, the fundamental differences between them are largely unclear. The aim of the current study is to investigate the fundamental differences between subcutaneous adipose tissue from CO and AO and to identify metabolic differences between abdominal (abSAT) and femoral subcutaneous adipose tissues (feSAT). Total and regional body composition was assessed using dual-energy x-ray absorptiometry (DXA) and computed tomography. Levels of acetyl-CoA, NAD+/NADH, acetyl-CoA network genes, mitochondrial complex abundance, H3 acetylation were determined in biopsied abSAT and feSAT. Serum leptin and adiponectin were measured. Our results showed that acetyl-CoA was higher in subcutaneous adipose tissue from subjects with AO compared with CO. Multiple linear regression revealed that ATP citrate lyase was the only main effect affecting the level of acetyl-CoA. Circulating leptin concentrations was higher in AO. The increased level of acetyl-CoA was strongly associated with histone H3 acetylation, LEP expression in adipose tissue, and circulating leptin in AO. NAD+/NADH was higher in CO; however, abundance of mitochondrial complexes, the complex II:complex V ratio, and the complex IV:complex V ratio were lower in CO, reflecting compromised mitochondrial function in subcutaneous adipose tissue from CO. Moreover, we identified differences in the level of acetyl-CoA and NAD+/NADH ratio between abSAT and feSAT, suggesting that these fat depots may possess different metabolic properties. The fundamental difference in the important metabolic intermediate acetyl-CoA between CO and AO may help us better understand the development of obesity and the pathogenesis of different obesity-related diseases in humans.
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Affiliation(s)
- Bjorn T Tam
- Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Metabolism, Obesity, Nutrition Lab, PERFORM Centre, Concordia University, Montreal, Quebec, Canada
| | - Jessica Murphy
- Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Metabolism, Obesity, Nutrition Lab, PERFORM Centre, Concordia University, Montreal, Quebec, Canada
| | - Natalie Khor
- Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Metabolism, Obesity, Nutrition Lab, PERFORM Centre, Concordia University, Montreal, Quebec, Canada
| | - Jose A Morais
- Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Division of Geriatric Medicine and Research Institute of McGill University Health Centre, Montreal, Quebec, Canada
| | - Sylvia Santosa
- Department of Health, Kinesiology, and Applied Physiology, Concordia University, Montreal, Quebec, Canada
- Metabolism, Obesity, Nutrition Lab, PERFORM Centre, Concordia University, Montreal, Quebec, Canada
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Ruan HB. Developmental and functional heterogeneity of thermogenic adipose tissue. J Mol Cell Biol 2020; 12:775-784. [PMID: 32569352 PMCID: PMC7816678 DOI: 10.1093/jmcb/mjaa029] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 05/11/2020] [Accepted: 06/12/2020] [Indexed: 12/18/2022] Open
Abstract
The obesity epidemic continues to rise as a global health challenge. Thermogenic brown and beige adipocytes dissipate chemical energy as heat, providing an opportunity for developing new therapeutics for obesity and related metabolic diseases. Anatomically, brown adipose tissue is distributed as discrete depots, while beige adipocytes exist within certain depots of white adipose tissue. Developmentally, brown and beige adipocytes arise from multiple embryonic progenitor populations that are distinct and overlapping. Functionally, they respond to a plethora of stimuli to engage uncoupling protein 1-dependent and independent thermogenic programs, thus improving systemic glucose homeostasis, lipid metabolism, and the clearance of branched-chain amino acids. In this review, we highlight recent advances in our understanding of the molecular and cellular mechanisms that contribute to the developmental and functional heterogeneity of thermogenic adipose tissue.
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Affiliation(s)
- Hai-Bin Ruan
- Department of Integrative Biology and Physiology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
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Nikolaou KC, Vatandaslar H, Meyer C, Schmid MW, Tuschl T, Stoffel M. The RNA-Binding Protein A1CF Regulates Hepatic Fructose and Glycerol Metabolism via Alternative RNA Splicing. Cell Rep 2020; 29:283-300.e8. [PMID: 31597092 DOI: 10.1016/j.celrep.2019.08.100] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 08/09/2019] [Accepted: 08/29/2019] [Indexed: 01/11/2023] Open
Abstract
The regulation of hepatic gene expression has been extensively studied at the transcriptional level; however, the control of metabolism through posttranscriptional gene regulation by RNA-binding proteins in physiological and disease states is less understood. Here, we report a major role for the hormone-sensitive RNA-binding protein (RBP) APOBEC1 complementation factor (A1CF) in the generation of hepatocyte-specific and alternatively spliced transcripts. Among these transcripts are isoforms for the dominant and high-affinity fructose-metabolizing ketohexokinase C and glycerol kinase, two key metabolic enzymes that are linked to hepatic gluconeogenesis and found to be markedly reduced upon hepatic ablation of A1cf. Consequently, mice lacking A1CF exhibit improved glucose tolerance and are protected from fructose-induced hyperglycemia, hepatic steatosis, and development of obesity. Our results identify a previously unreported function of A1CF as a regulator of alternative splicing of a subset of genes influencing hepatic glucose production through fructose and glycerol metabolism.
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Affiliation(s)
- Kostas C Nikolaou
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, 8093 Zürich, Switzerland
| | - Hasan Vatandaslar
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, 8093 Zürich, Switzerland
| | - Cindy Meyer
- Laboratory of RNA Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Marc W Schmid
- MWSchmid GmbH, Möhrlistrasse 25, 8006 Zurich, Switzerland
| | - Thomas Tuschl
- Laboratory of RNA Molecular Biology, The Rockefeller University, 1230 York Avenue, New York, NY 10021, USA
| | - Markus Stoffel
- Institute of Molecular Health Sciences, ETH Zurich, Otto-Stern-Weg 7, 8093 Zürich, Switzerland; Medical Faculty, University of Zurich, 8091 Zurich, Switzerland.
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Chen L, Chen H, Liu X, Li J, Gao Q, Shi S, Wang T, Ye X, Lu Y, Zhang D, Sheng J, Jin L, Huang H. AQP7 mediates post-menopausal lipogenesis in adipocytes through FSH-induced transcriptional crosstalk with AP-1 sites. Reprod Biomed Online 2020; 41:1122-1132. [PMID: 33132060 DOI: 10.1016/j.rbmo.2020.08.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 08/02/2020] [Accepted: 08/11/2020] [Indexed: 10/23/2022]
Abstract
RESEARCH QUESTION Fat accumulation is present in most post-menopausal women, but the underlying mechanism remains unclear. Aquaporin 7 (AQP7) is the most important glycerol channel facilitating glycerol efflux in adipocytes. High circulating FSH in post-menopausal women may play an independent role in regulation of the lipogenic effect of AQP7 in adipocytes. This study explored the role of AQP7 in the pathophysiology of post-menopausal lipogenesis mediated by high concentrations of circulating FSH. DESIGN Primary adipocytes from post-menopausal and childbearing women were analysed. An in-vivo post-menopausal animal model was established. AQP7 expression, lipid accumulation and glycerol concentration in adipocytes were measured. Luciferase reporter assay and chromatin immunoprecipitation were performed to identify transcriptional crosstalk in AQP7 promoter. RESULTS It was found that FSH down-regulated AQP7 expression and glycerol efflux function in mature adipocytes of post-menopausal women and ovariectomized (OVX) mice. In vitro, FSH inhibited lipid accumulation in primary cultured mature adipocytes in a dose-dependent manner and the mechanism was down-regulating AQP7 expression via a FSH receptor pathway. The effect of FSH on AQP7 in adipocytes was through activation of cAMP response element-binding (CREB) protein, which could bind to activator protein-1 (AP-1) sites in the AQP7 promoter, and therefore inhibited the transcriptional activation elicited by c-Jun. CONCLUSIONS Down-regulation of AQP7 by FSH mediated post-menopausal lipogenesis, and the role of FSH was based on binding competition for AP-1 sites between CREB and c-Jun.
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Affiliation(s)
- Luting Chen
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China; Shanghai Key Laboratory of Embryo Original Disease Shanghai, China
| | - Huixi Chen
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China; Shanghai Key Laboratory of Embryo Original Disease Shanghai, China
| | - Xinmei Liu
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China; Shanghai Key Laboratory of Embryo Original Disease Shanghai, China
| | - Jingyi Li
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China; Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Qian Gao
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China
| | - Shuai Shi
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China
| | - Tingting Wang
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China
| | - Xiaoqun Ye
- Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Yongchao Lu
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China; Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Dan Zhang
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China; Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Jianzhong Sheng
- Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China
| | - Li Jin
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China; Shanghai Key Laboratory of Embryo Original Disease Shanghai, China.
| | - Hefeng Huang
- International Peace Maternity and Child Health Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai, China; Shanghai Key Laboratory of Embryo Original Disease Shanghai, China; Key Laboratory of Reproductive Genetics (Zhejiang University), Ministry of Education, Hangzhou Zhejiang, China.
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UCP1-independent thermogenesis. Biochem J 2020; 477:709-725. [PMID: 32059055 DOI: 10.1042/bcj20190463] [Citation(s) in RCA: 79] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Revised: 01/20/2020] [Accepted: 01/21/2020] [Indexed: 12/24/2022]
Abstract
Obesity results from energy imbalance, when energy intake exceeds energy expenditure. Brown adipose tissue (BAT) drives non-shivering thermogenesis which represents a powerful mechanism of enhancing the energy expenditure side of the energy balance equation. The best understood thermogenic system in BAT that evolved to protect the body from hypothermia is based on the uncoupling of protonmotive force from oxidative phosphorylation through the actions of uncoupling protein 1 (UCP1), a key regulator of cold-mediated thermogenesis. Similarly, energy expenditure is triggered in response to caloric excess, and animals with reduced thermogenic fat function can succumb to diet-induced obesity. Thus, it was surprising when inactivation of Ucp1 did not potentiate diet-induced obesity. In recent years, it has become clear that multiple thermogenic mechanisms exist, based on ATP sinks centered on creatine, lipid, or calcium cycling, along with Fatty acid-mediated UCP1-independent leak pathways driven by the ADP/ATP carrier (AAC). With a key difference between cold- and diet-induced thermogenesis being the dynamic changes in purine nucleotide (primarily ATP) levels, ATP-dependent thermogenic pathways may play a key role in diet-induced thermogenesis. Additionally, the ubiquitous expression of AAC may facilitate increased energy expenditure in many cell types, in the face of over feeding. Interest in UCP1-independent energy expenditure has begun to showcase the therapeutic potential that lies in refining our understanding of the diversity of biochemical pathways controlling thermogenic respiration.
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Buzelle SL, Przygodda F, Rossi-Valentim R, Ferreira GN, Garófalo MAR, Alves VM, Chaves VE, Navegantes LCC, Kettelhut IDC. Activation of adipose tissue glycerokinase contributes to increased white adipose tissue mass in mice fed a high-fat diet. Endocrine 2020; 69:79-91. [PMID: 32297203 DOI: 10.1007/s12020-020-02288-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/18/2019] [Accepted: 03/25/2020] [Indexed: 01/04/2023]
Abstract
PURPOSE Investigate the pathways of glycerol-3-P (G3P) generation for triacylglycerol (TAG) synthesis in retroperitoneal (RWAT) and epididymal (EWAT) white adipose tissues from high-fat diet (HFD)-fed mice. METHODS Mice were fed for 8 weeks a HFD and glycolysis, glyceroneogenesis and direct phosphorylation of glycerol were evaluated, respectively, by 2-deoxyglucose uptake, phosphoenolpyruvate carboxykinase (PEPCK-C) activity and pyruvate incorporation into TAG-glycerol, and glycerokinase activity and glycerol incorporation into TAG-glycerol in both tissues. RESULTS HFD increased body and adipose tissue mass and serum levels of glucose and insulin, which were accompanied by glucose intolerance. RWAT and EWAT from HFD-fed mice had increased rates of de novo fatty acid (FA) synthesis (52% and 255%, respectively). HFD increased lipoprotein lipase (LPL) activity and content in EWAT (107%), but decreased in RWAT (79%). HFD decreased the lipolytic response to norepinephrine (57%, RWAT and 25%, EWAT), β3-adrenoceptor content (50%), which was accompanied by a decrease in phosphorylated-hormone-sensitive lipase (~80%) and phosphorylated-adipocyte triacylglycerol lipase (~60%) in both tissues. HFD decreased the in vitro rates of glucose uptake (3.5- and 6-fold), as well as in glyceride-glycerol synthesis from pyruvate (~3.5-fold) without changes in PEPCK-C activity and content in RWAT and EWAT, but increased glycerokinase activity(~3-fold) and content (90 and 40%) in both tissues. CONCLUSION The data suggest that direct phosphorylation of glycerol by glycerokinase may be responsible for maintaining the supply of G3P for the existing rates of FA esterification and TAG synthesis in RWAT and EWAT from HFD-fed mice, contributing, along with a lower lipolytic response to norepinephrine, to higher adiposity.
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Affiliation(s)
- Samyra Lopes Buzelle
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Franciele Przygodda
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rafael Rossi-Valentim
- Department of Physiology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | | | | | - Vani Maria Alves
- Department of Cell and Molecular Biology and Pathogenic Bioagents, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Valéria Ernestânia Chaves
- Laboratory of Physiology, Federal University of São João del-Rei, Divinópolis, Minas Gerais, Brazil.
| | | | - Isis do Carmo Kettelhut
- Department of Biochemistry and Immunology, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, São Paulo, Brazil
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Iwase M, Tokiwa S, Seno S, Mukai T, Yeh YS, Takahashi H, Nomura W, Jheng HF, Matsumura S, Kusudo T, Osato N, Matsuda H, Inoue K, Kawada T, Goto T. Glycerol kinase stimulates uncoupling protein 1 expression by regulating fatty acid metabolism in beige adipocytes. J Biol Chem 2020; 295:7033-7045. [PMID: 32273338 DOI: 10.1074/jbc.ra119.011658] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 04/02/2020] [Indexed: 11/06/2022] Open
Abstract
Browning of adipose tissue is induced by specific stimuli such as cold exposure and consists of up-regulation of thermogenesis in white adipose tissue. Recently, it has emerged as an attractive target for managing obesity in humans. Here, we performed a comprehensive analysis to identify genes associated with browning in murine adipose tissue. We focused on glycerol kinase (GYK) because its mRNA expression pattern is highly correlated with that of uncoupling protein 1 (UCP1), which regulates the thermogenic capacity of adipocytes. Cold exposure-induced Ucp1 up-regulation in inguinal white adipose tissue (iWAT) was partially abolished by Gyk knockdown (KD) in vivo Consistently, the Gyk KD inhibited Ucp1 expression induced by treatment with the β-adrenergic receptors (βAR) agonist isoproterenol (Iso) in vitro and resulted in impaired uncoupled respiration. Gyk KD also suppressed Iso- and adenylate cyclase activator-induced transcriptional activation and phosphorylation of the cAMP response element-binding protein (CREB). However, we did not observe these effects with a cAMP analog. Therefore Gyk KD related to Iso-induced cAMP products. In Iso-treated Gyk KD adipocytes, stearoyl-CoA desaturase 1 (SCD1) was up-regulated, and monounsaturated fatty acids such as palmitoleic acid (POA) accumulated. Moreover, a SCD1 inhibitor treatment recovered the Gyk KD-induced Ucp1 down-regulation and POA treatment down-regulated Iso-activated Ucp1 Our findings suggest that Gyk stimulates Ucp1 expression via a mechanism that partially depends on the βAR-cAMP-CREB pathway and Gyk-mediated regulation of fatty acid metabolism.
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Affiliation(s)
- Mari Iwase
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Soshi Tokiwa
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Shigeto Seno
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Suita 565-0871, Japan
| | - Takako Mukai
- Faculty of Human Sciences, Tezukayama Gakuin University, Sakai 590-0113, Japan
| | - Yu-Sheng Yeh
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Haruya Takahashi
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Wataru Nomura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.,Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto 606-8317, Japan
| | - Huei-Fen Jheng
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Sigenobu Matsumura
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Tatsuya Kusudo
- Faculty of Human Sciences, Tezukayama Gakuin University, Sakai 590-0113, Japan
| | - Naoki Osato
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Suita 565-0871, Japan
| | - Hideo Matsuda
- Department of Bioinformatic Engineering, Graduate School of Information Science and Technology, Osaka University, Suita 565-0871, Japan
| | - Kazuo Inoue
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan
| | - Teruo Kawada
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan.,Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto 606-8317, Japan
| | - Tsuyoshi Goto
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Uji, Kyoto 611-0011, Japan .,Research Unit for Physiological Chemistry, Center for the Promotion of Interdisciplinary Education and Research, Kyoto University, Kyoto 606-8317, Japan
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Endogenous FGF21-signaling controls paradoxical obesity resistance of UCP1-deficient mice. Nat Commun 2020; 11:624. [PMID: 32005798 PMCID: PMC6994690 DOI: 10.1038/s41467-019-14069-2] [Citation(s) in RCA: 56] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2019] [Accepted: 12/10/2019] [Indexed: 01/01/2023] Open
Abstract
Uncoupling protein 1 (UCP1) executes thermogenesis in brown adipose tissue, which is a major focus of human obesity research. Although the UCP1-knockout (UCP1 KO) mouse represents the most frequently applied animal model to judge the anti-obesity effects of UCP1, the assessment is confounded by unknown anti-obesity factors causing paradoxical obesity resistance below thermoneutral temperatures. Here we identify the enigmatic factor as endogenous FGF21, which is primarily mediating obesity resistance. The generation of UCP1/FGF21 double-knockout mice (dKO) fully reverses obesity resistance. Within mild differences in energy metabolism, urine metabolomics uncover increased secretion of acyl-carnitines in UCP1 KOs, suggesting metabolic reprogramming. Strikingly, transcriptomics of metabolically important organs reveal enhanced lipid and oxidative metabolism in specifically white adipose tissue that is fully reversed in dKO mice. Collectively, this study characterizes the effects of endogenous FGF21 that acts as master regulator to protect from diet-induced obesity in the absence of UCP1. Brown adipose thermogenesis increases energy expenditure and relies on uncoupling protein 1 (UCP1), however, UCP1 knock-out mice show resistance to diet-induced obesity at room temperature. Here, the authors show that this resistance relies on FGF21-signaling, inducing the browning of white adipose tissue.
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Jastroch M, Seebacher F. Importance of adipocyte browning in the evolution of endothermy. Philos Trans R Soc Lond B Biol Sci 2020; 375:20190134. [PMID: 31928187 DOI: 10.1098/rstb.2019.0134] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Endothermy changes the relationship between organisms and their environment fundamentally, and it is therefore of major ecological and evolutionary significance. Endothermy is characterized by non-shivering thermogenesis, that is metabolic heat production in the absence of muscular activity. In many eutherian mammals, brown adipose tissue (BAT) is an evolutionary innovation that facilitates non-shivering heat production in mitochondria by uncoupling food-derived substrate oxidation from chemical energy (ATP) production. Consequently, energy turnover is accelerated resulting in increased heat release. The defining characteristics of BAT are high contents of mitochondria and vascularization, and the presence of uncoupling protein 1. Recent insights, however, reveal that a range of stimuli such as exercise, diet and the immune system can cause the browning of white adipocytes, thereby increasing energy expenditure and heat production even in the absence of BAT. Here, we review the molecular mechanisms that cause browning of white adipose tissue, and their potential contribution to thermoregulation. The significance for palaeophysiology lies in the presence of adipose tissue and the mechanisms that cause its browning and uncoupling in all amniotes. Hence, adipocytes may have played a role in the evolution of endothermy beyond the more specific evolution of BAT in eutherians. This article is part of the theme issue 'Vertebrate palaeophysiology'.
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Affiliation(s)
- Martin Jastroch
- Department of Molecular Biosciences, The Wenner-Gren Institute, Stockholm University, 106 91 Stockholm, Sweden
| | - Frank Seebacher
- School of Life and Environmental Sciences A08, University of Sydney, Sydney, NSW 2006, Australia
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Fujii M, Ota K, Bessho R. Cardioprotective effect of hyperkalemic cardioplegia in an aquaporin 7-deficient murine heart. Gen Thorac Cardiovasc Surg 2019; 68:578-584. [PMID: 31707553 DOI: 10.1007/s11748-019-01243-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 10/25/2019] [Indexed: 11/30/2022]
Abstract
BACKGROUND Hyperkalemic cardioplegia using St. Thomas' Hospital solution No. 2 (STH2) is commonly used to protect the myocardium during surgery. Mice deficient in the myocyte channel aquaporin 7 (AQP7) show significantly reduced glycerol and ATP contents and develop obesity; however, the influence of AQP7 on cardioplegia effectiveness remains unclear. METHODS After determining the influence of ischemic duration on cardiac function, isolated hearts of male wild-type (WT) and AQP7-knockout (KO) mice (> 13 weeks old) were aerobically Langendorff-perfused with bicarbonate buffer, and randomly allocated to the control group (25 min of global ischemia) and STH2 group (5 min of STH2 infusion before 20 min of global ischemia, followed by 60 min of reperfusion). RESULTS Final recovery of left ventricular developed pressure (LVDP) of WT and AQP7-KO hearts in the control group was 24.5 ± 12.4% and 20.6 ± 8.4%, respectively, which were significantly lower than those of the STH2 group (96.4 ± 12.7% and 92.9 ± 27.6%). Troponin T levels of WT and AQP-KO hearts significantly decreased in the STH2 groups (142.9 ± 27.2 and 219.9 ± 197.3) compared to those of the control (1725.0 ± 768.6 and 1710 ± 819.9). CONCLUSIONS AQP7 was not involved in the protective efficacy of STH2 in this mouse model, suggesting its clinical utility even in complications of metabolic disease.
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Affiliation(s)
- Masahiro Fujii
- Department of Cardiovascular Surgery, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba, 270-1694, Japan.
| | - Keisuke Ota
- Department of Cardiovascular Surgery, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba, 270-1694, Japan
| | - Ryuzo Bessho
- Department of Cardiovascular Surgery, Nippon Medical School Chiba Hokusoh Hospital, 1715 Kamagari, Inzai, Chiba, 270-1694, Japan
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Patel BM, Goyal RK. Liver and insulin resistance: New wine in old bottle!!! Eur J Pharmacol 2019; 862:172657. [DOI: 10.1016/j.ejphar.2019.172657] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 09/02/2019] [Accepted: 09/05/2019] [Indexed: 12/20/2022]
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Peroxisome Proliferator Activated Receptor Gamma Controls Mature Brown Adipocyte Inducibility through Glycerol Kinase. Cell Rep 2019; 22:760-773. [PMID: 29346772 DOI: 10.1016/j.celrep.2017.12.067] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2017] [Revised: 10/03/2017] [Accepted: 12/20/2017] [Indexed: 01/08/2023] Open
Abstract
Peroxisome proliferator-activated receptors (PPARs) have been suggested as the master regulators of adipose tissue formation. However, their role in regulating brown fat functionality has not been resolved. To address this question, we generated mice with inducible brown fat-specific deletions of PPARα, β/δ, and γ, respectively. We found that both PPARα and β/δδ are dispensable for brown fat function. In contrast, we could show that ablation of PPARγ in vitro and in vivo led to a reduced thermogenic capacity accompanied by a loss of inducibility by β-adrenergic signaling, as well as a shift from oxidative fatty acid metabolism to glucose utilization. We identified glycerol kinase (Gyk) as a partial mediator of PPARγ function and could show that Gyk expression correlates with brown fat thermogenic capacity in human brown fat biopsies. Thus, Gyk might constitute the link between PPARγ-mediated regulation of brown fat function and activation by β-adrenergic signaling.
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