1
|
Wang B, Steinberg GR. Environmental toxicants, brown adipose tissue, and potential links to obesity and metabolic disease. Curr Opin Pharmacol 2022; 67:102314. [PMID: 36334331 DOI: 10.1016/j.coph.2022.102314] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2022] [Revised: 07/12/2022] [Accepted: 10/03/2022] [Indexed: 12/15/2022]
Abstract
Rates of human obesity, type 2 diabetes, and non-alcoholic fatty liver disease (NAFLD) have risen faster than anticipated and cannot solely be explained by excessive caloric intake or physical inactivity. Importantly, this effect is also observed in many other domesticated and non-domesticated mammals, which has led to the hypothesis that synthetic environmental pollutants may be contributing to disease development. While the impact of these chemicals on appetite and adipogenesis has been extensively studied, their potential role in reducing energy expenditure is less studied. An important component of whole-body energy expenditure is adaptive and diet-induced thermogenesis in human brown adipose tissue (BAT). This review summarizes recent evidence that environmental pollutants such as the pesticide chlorpyrifos inhibit BAT function, diet-induced thermogenesis and the potential signaling pathways mediating these effects. Lastly, we discuss the importance of housing experimental mice at thermoneutrality, rather than room temperature, to maximize the translation of findings to humans.
Collapse
Affiliation(s)
- Bo Wang
- State Key Laboratory of Animal Nutrition, College of Animal Science and Technology, China Agricultural University, Beijing, 100193, PR China.
| | - Gregory R Steinberg
- Centre for Metabolism, Obesity and Diabetes Research, Canada; Division of Endocrinology and Metabolism, Department of Medicine, Canada; Department of Biochemistry and Biomedical Sciences, McMaster University, Canada
| |
Collapse
|
2
|
Sun W, Luo Y, Zhang F, Tang S, Zhu T. Involvement of TRP Channels in Adipocyte Thermogenesis: An Update. Front Cell Dev Biol 2021; 9:686173. [PMID: 34249940 PMCID: PMC8264417 DOI: 10.3389/fcell.2021.686173] [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: 03/26/2021] [Accepted: 06/02/2021] [Indexed: 01/27/2023] Open
Abstract
Obesity prevalence became a severe global health problem and it is caused by an imbalance between energy intake and expenditure. Brown adipose tissue (BAT) is a major site of mammalian non-shivering thermogenesis or energy dissipation. Thus, modulation of BAT thermogenesis might be a promising application for body weight control and obesity prevention. TRP channels are non-selective calcium-permeable cation channels mainly located on the plasma membrane. As a research focus, TRP channels have been reported to be involved in the thermogenesis of adipose tissue, energy metabolism and body weight regulation. In this review, we will summarize and update the recent progress of the pathological/physiological involvement of TRP channels in adipocyte thermogenesis. Moreover, we will discuss the potential of TRP channels as future therapeutic targets for preventing and combating human obesity and related-metabolic disorders.
Collapse
Affiliation(s)
- Wuping Sun
- Department of Pain Medicine and Shenzhen Municipal Key Laboratory for Pain Medicine, Shenzhen Nanshan People's Hospital and The 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Yixuan Luo
- Department of Cardiovascular Surgery, Shenzhen Nanshan People's Hospital and The 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Fei Zhang
- Department of Cardiovascular Surgery, Shenzhen Nanshan People's Hospital and The 6th Affiliated Hospital of Shenzhen University Health Science Center, Shenzhen, China
| | - Shuo Tang
- Department of Orthopaedics, The Eighth Affiliated Hospital, Sun Yat-sen University, Shenzhen, China
| | - Tao Zhu
- Department of Respiratory Medicine, Second Affiliated Hospital of Chongqing Medical University, Chongqing, China
| |
Collapse
|
3
|
Pravednikova AE, Shevchenko SY, Kerchev VV, Skhirtladze MR, Larina SN, Kachaev ZM, Egorov AD, Shidlovskii YV. Association of uncoupling protein (Ucp) gene polymorphisms with cardiometabolic diseases. Mol Med 2020; 26:51. [PMID: 32450815 PMCID: PMC7249395 DOI: 10.1186/s10020-020-00180-4] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2020] [Accepted: 05/11/2020] [Indexed: 12/23/2022] Open
Abstract
The hereditary aspect of obesity is a major focus of modern medical genetics. The genetic background is known to determine a higher-than-average prevalence of obesity in certain regions, like Oceania. There is evidence that dysfunction of brown adipose tissue (BAT) may be a risk factor for obesity and type 2 diabetes (T2D). A significant number of studies in the field focus on the UCP family. The Ucp genes code for electron transport carriers. UCP1 (thermogenin) is the most abundant protein of the UCP superfamily and is expressed in BAT, contributing to its capability of generating heat. Single nucleotide polymorphisms (SNPs) of Ucp1-Ucp3 were recently associated with risk of cardiometabolic diseases. This review covers the main Ucp SNPs A-3826G, A-1766G, A-112C, Met229Leu, Ala64Thr (Ucp1), Ala55Val, G-866A (Ucp2), and C-55 T (Ucp3), which may be associated with the development of obesity, disturbance in lipid metabolism, T2D, and cardiovascular diseases.
Collapse
Affiliation(s)
- Anna E. Pravednikova
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Sergey Y. Shevchenko
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Victor V. Kerchev
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Manana R. Skhirtladze
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Svetlana N. Larina
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| | - Zaur M. Kachaev
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Alexander D. Egorov
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
| | - Yulii V. Shidlovskii
- Laboratory of Gene Expression Regulation in Development, Institute of Gene Biology, Russian Academy of Sciences, Moscow, Russia
- I.M. Sechenov First Moscow State Medical University, Ministry of Health of the Russian Federation, Moscow, Russia
| |
Collapse
|
4
|
Saito M, Matsushita M, Yoneshiro T, Okamatsu-Ogura Y. Brown Adipose Tissue, Diet-Induced Thermogenesis, and Thermogenic Food Ingredients: From Mice to Men. Front Endocrinol (Lausanne) 2020; 11:222. [PMID: 32373072 PMCID: PMC7186310 DOI: 10.3389/fendo.2020.00222] [Citation(s) in RCA: 110] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 03/27/2020] [Indexed: 12/28/2022] Open
Abstract
Since the recent rediscovery of brown adipose tissue (BAT) in adult humans, this thermogenic tissue has been attracting increasing interest. The inverse relationship between BAT activity and body fatness suggests that BAT, because of its energy dissipating activity, is protective against body fat accumulation. Cold exposure activates and recruits BAT, resulting in increased energy expenditure and decreased body fatness. The stimulatory effects of cold exposure are mediated through transient receptor potential (TRP) channels and the sympathetic nervous system (SNS). Most TRP members also function as chemesthetic receptors for various food ingredients, and indeed, agonists of TRP vanilloid 1 such as capsaicin and its analog capsinoids mimic the effects of cold exposure to decrease body fatness through the activation and recruitment of BAT. The antiobesity effect of other food ingredients including tea catechins may be attributable, at least in part, to the activation of the TRP-SNS-BAT axis. BAT is also involved in the facultative thermogenesis induced by meal intake, referred to as diet-induced thermogenesis (DIT), which is a significant component of the total energy expenditure in our daily lives. Emerging evidence suggests a crucial role for the SNS in BAT-associated DIT, particularly during the early phase, but several gut-derived humoral factors may also participate in meal-induced BAT activation. One intriguing factor is bile acids, which activate BAT directly through Takeda G-protein receptor 5 (TGR5) in brown adipocytes. Given the apparent beneficial effects of some TRP agonists and bile acids on whole-body substrate and energy metabolism, the TRP/TGR5-BAT axis represents a promising target for combating obesity and related metabolic disorders in humans.
Collapse
Affiliation(s)
- Masayuki Saito
- Faculty of Veterinary Medicine, Hokkaido University, Sapporo, Japan
- *Correspondence: Masayuki Saito
| | | | - Takeshi Yoneshiro
- Division of Metabolic Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo, Japan
| | | |
Collapse
|
5
|
Flouris AD, Shidlovskii YV, Shaposhnikov AV, Yepiskoposyan L, Nadolnik L, Karabon L, Kowalska A, Carrillo AE, Metsios GS, Sakellariou P. Role of UCP1 Gene Variants in Interethnic Differences in the Development of Cardio-Metabolic Diseases. Front Genet 2017; 8:7. [PMID: 28194159 PMCID: PMC5277005 DOI: 10.3389/fgene.2017.00007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2016] [Accepted: 01/16/2017] [Indexed: 12/04/2022] Open
Abstract
Cardio-metabolic diseases (CMDs) comprise a cluster of risk factors that contribute to chronic pathological conditions with adverse consequences for cardiovascular function and metabolic processes. A wide range of CMD prevalence rates among different ethnic groups has been documented. In view of accumulated evidence, there is a trend toward increasing CMD prevalence rates in Eastern Europe and Western Asia. Numerous studies have revealed an association between uncoupling protein 1 (UCP1) gene variants and CMDs. UCP1 activity is essential for brown adipose tissue (BAT)-mediated thermogenesis. Experimental animal studies and epidemiological studies in humans highlight the significance of BAT-mediated thermogenesis in protecting against obesity and maintaining a lean phenotype. We hypothesize that the genetic variation in UCP1 gene expression observed among different ethnic groups could contribute to the ethnic-specific predisposition to CMD development. Constructing such prevalence maps of UCP1 gene variants could contribute significantly into identifying high-risk ethnic groups predisposed to the development of CMDs, and further shaping public health policies by the improvement of existing preventive and management strategies.
Collapse
Affiliation(s)
- Andreas D Flouris
- FAME Laboratory, Institute of Research and Technology Thessaly, Centre for Research and Technology Hellas Trikala, Greece
| | | | | | | | - Liliya Nadolnik
- Institute of Biochemistry of Biologically Active Compounds - National Academy of Sciences of Belarus Grodno, Belarus
| | - Lidia Karabon
- Institute of Immunology and Experimental Therapy - Polish Academy of Sciences Wrocław, Poland
| | - Anna Kowalska
- Institute of Immunology and Experimental Therapy - Polish Academy of Sciences Wrocław, Poland
| | - Andres E Carrillo
- FAME Laboratory, Institute of Research and Technology Thessaly, Centre for Research and Technology HellasTrikala, Greece; Department of Exercise Science, Chatham University, PittsburghPA, USA
| | - George S Metsios
- Faculty of Education, Health and Wellbeing, Wolverhampton University Walsall, UK
| | - Paraskevi Sakellariou
- FAME Laboratory, Institute of Research and Technology Thessaly, Centre for Research and Technology Hellas Trikala, Greece
| |
Collapse
|
6
|
Saito M, Yoneshiro T, Matsushita M. Activation and recruitment of brown adipose tissue by cold exposure and food ingredients in humans. Best Pract Res Clin Endocrinol Metab 2016; 30:537-547. [PMID: 27697214 DOI: 10.1016/j.beem.2016.08.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Since the recent re-discovery of brown adipose tissue (BAT) in adult humans, this thermogenic tissue has attracted increasing interest. The inverse relationship between the BAT activity and body fatness suggests that BAT, because of its energy dissipating activity, is protective against body fat accumulation. Cold exposure activates and recruits BAT in association with increased energy expenditure and decreased body fatness. The stimulatory effects of cold are mediated through transient receptor potential channels (TRP), most of which are also chemesthetic receptors for various food ingredients. In fact, capsaicin and its analog capsinoids, representative agonists of TRPV1, mimic the effects of cold to decrease body fatness through the activation and recruitment of BAT. The anti-obesity effect of some other food ingredients including tea catechins may also be attributable to the activation of the TRP-BAT axis. Thus, BAT is a promising target for combating obesity and related metabolic disorders in humans.
Collapse
Affiliation(s)
- Masayuki Saito
- Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan; Department of Nutrition, Tenshi College, Sapporo 065-0013, Japan.
| | - Takeshi Yoneshiro
- Department of Biomedical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan.
| | - Mami Matsushita
- Department of Nutrition, Tenshi College, Sapporo 065-0013, Japan.
| |
Collapse
|
7
|
Capsaicin and Related Food Ingredients Reducing Body Fat Through the Activation of TRP and Brown Fat Thermogenesis. ADVANCES IN FOOD AND NUTRITION RESEARCH 2015; 76:1-28. [PMID: 26602570 DOI: 10.1016/bs.afnr.2015.07.002] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
Brown adipose tissue (BAT) is a site of sympathetically activated adaptive nonshivering thermogenesis, thereby being involved in the regulation of energy balance and body fatness. Recent radionuclide imaging studies have revealed the existence of metabolically active BAT in adult humans. Human BAT is activated by acute cold exposure and contributes to cold-induced increase in whole-body energy expenditure. The metabolic activity of BAT is lower in older and obese individuals. The inverse relationship between the BAT activity and body fatness suggests that BAT, because of its energy dissipating activity, is protective against body fat accumulation. In fact, repeated cold exposure recruits BAT in association with increased energy expenditure and decreased body fatness. The stimulatory effects of cold are mediated through the activation of transient receptor potential (TRP) channels, most of which are also chemesthetic receptors for various naturally occurring substances including herbal plants and food ingredients. Capsaicin and its analog capsinoids, representative agonists of TRPV1, mimic the effects of cold to decrease body fatness through the activation and recruitment of BAT. The well-known antiobesity effect of green tea catechins is also attributable to the activation of the sympathetic nerve and BAT system. Thus, BAT is a promising target for combating obesity and related metabolic disorders in humans.
Collapse
|
8
|
Messmer MN, Kokolus KM, Eng JWL, Abrams SI, Repasky EA. Mild cold-stress depresses immune responses: Implications for cancer models involving laboratory mice. Bioessays 2014; 36:884-91. [PMID: 25066924 DOI: 10.1002/bies.201400066] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Physiologically accurate mouse models of cancer are critical in the pre-clinical development of novel cancer therapies. However, current standardized animal-housing temperatures elicit chronic cold-associated stress in mice, which is further increased in the presence of tumor. This cold-stress significantly impacts experimental outcomes. Data from our lab and others suggest standard housing fundamentally alters murine physiology, and this can produce altered immune baselines in tumor and other disease models. Researchers may thus underestimate the efficacy of therapies that are benefitted by immune responses. A potential mediator, norepinephrine, also underlies stress pathways common in mice and humans. Therefore, research into mechanisms connecting cold-stress and norepinephrine signaling with immune depression in mice could highlight new combination therapies for humans to simultaneously target stress while stimulating anti-tumor immunity.
Collapse
Affiliation(s)
- Michelle N Messmer
- Department of Immunology, Roswell Park Cancer Institute, Buffalo, NY, USA
| | | | | | | | | |
Collapse
|
9
|
Abstract
Brown adipose tissue (BAT) is recognized as the major site of sympathetically activated nonshivering thermogenesis during cold exposure and after spontaneous hyperphagia, thereby controling whole-body energy expenditure and body fat. In adult humans, BAT has long been believed to be absent or negligible, but recent studies using fluorodeoxyglucose-positron emission tomography, in combination with computed tomography, demonstrated the existence of metabolically active BAT in healthy adult humans. Human BAT is activated by acute cold exposure, being positively correlated to cold-induced increases in energy expenditure. The metabolic activity of BAT differs among individuals, being lower in older and obese individuals. Thus, BAT is recognized as a regulator of whole-body energy expenditure and body fat in humans as in small rodents, and a hopeful target combating obesity and related disorders. In fact, there are some food ingredients such as capsaicin and capsinoids, which have potential to activate and recruit BAT via activity on the specific receptor, transient receptor potential channels, thereby increasing energy expenditure and decreasing body fat modestly and consistently.
Collapse
|
10
|
Impact of UCP1 and β3AR gene polymorphisms on age-related changes in brown adipose tissue and adiposity in humans. Int J Obes (Lond) 2012; 37:993-8. [PMID: 23032405 DOI: 10.1038/ijo.2012.161] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/09/2012] [Revised: 08/22/2012] [Accepted: 08/29/2012] [Indexed: 12/21/2022]
Abstract
BACKGROUND Brown adipose tissue (BAT) is involved in the regulation of whole-body energy expenditure and adiposity. The activity and prevalence of BAT decrease with age in humans. OBJECTIVE To examine the effects of single nucleotide polymorphisms of the genes for uncoupling protein 1 (UCP1) and β3-adrenergic receptor (β3AR), key molecules of BAT thermogenesis, on age-related decline of BAT activity and accumulation of body fat in humans. METHODS One hundred ninety-nine healthy volunteers (20-72 years old (y.o.)) underwent fluorodeoxyglucose-positron emission tomography (FDG-PET) and computed tomography (CT) after 2-h cold exposure to assess BAT activity. The visceral and subcutaneous fat areas at the abdominal level were estimated from the CT images. They were genotyped for -3826 A/G polymorphism of the UCP1 gene and 64 Trp/Arg mutation of the β3AR gene. RESULTS BAT was detected in 88 subjects out of 199 (44%), more in younger (30 y.o., 55%) than older subjects (>40 y.o., 15%). BAT prevalence of older subjects tended to be lower in the UCP1 G/G group than the A allele group (A/A and A/G), and also in the β3AR Arg allele group (Trp/Arg and Arg/Arg) than the Trp/Trp group. When compared subjects who had two or more base substitutions on the two genes (the 2-4 allele group) with those who had less than two base substitutions (the 0-1 allele group), BAT prevalence was comparable in younger subjects (62% vs 50%) but lower in older subjects (0% vs 24%, P<0.05). Visceral fat area of the 2-4 allele group was higher than that of the 0-1 allele group (P<0.05) in older subjects, but not in younger subjects. CONCLUSION UCP1 -3826 A/G and β3AR 64 Trp/Arg substitutions accelerate age-related decrease in BAT activity, and thereby may associate with visceral fat accumulation with age.
Collapse
|
11
|
Uncoupling protein 1 gene −3826 A/G polymorphism is associated with weight loss on a short-term, controlled-energy diet in young women. Nutr Res 2011; 31:255-61. [DOI: 10.1016/j.nutres.2011.03.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2010] [Revised: 03/14/2011] [Accepted: 03/16/2011] [Indexed: 11/21/2022]
|
12
|
UCP1 genetic polymorphism (-3826 A/G) diminishes resting energy expenditure and thermoregulatory sympathetic nervous system activity in young females. Int J Obes (Lond) 2010; 35:1050-5. [PMID: 21189472 DOI: 10.1038/ijo.2010.261] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Recent findings regarding the existence of functional brown adipose tissue (BAT) in adult humans suggest a physiological role of BAT and uncoupling protein 1 (UCP1)-linked thermogenesis in energy balance. OBJECTIVE To investigate whether UCP1 polymorphism was associated with resting energy expenditure (REE) and thermoregulatory sympathetic nervous system (SNS) activity in humans. METHODS A total of 82 healthy females (20-22 years) were genotyped for the -3826 A/G polymorphism of the UCP1 gene using a fluorescent allele-specific DNA primer assay system. REE was measured by indirect calorimetry. The thermoregulatory SNS activity was assessed by heart rate variability power spectral analysis according to our previously reported method. Each subject was studied in the morning, after an overnight fast. Nutritional values were calculated on the basis of 2-day food records. RESULTS The frequencies of A/A, A/G and G/G genotypes were 0.27, 0.45 and 0.28, respectively. No significant difference was found in anthropometric indexes among the three groups. However, in the G/G group, the percentage of energy consumed as fat was lower (A/A: 30.7 ± 1.1%, A/G: 31.3 ± 1.0%, G/G: 26.0 ± 1.2%, P<0.01), and energy intake tended to be lower (A/A: 7209 ± 310 kJ d(-1), A/G: 7075 ± 280 kJ d(-1), G/G: 6414 ± 264 kJ d(-1), P=0.16). With regard to metabolic parameters, group differences were observed in REE (A/A: 5599 ± 170 kJ d(-1), A/G: 5054 ± 115 kJ d(-1), G/G: 4919 ± 182 kJ d(-1), P<0.01) and in thermoregulatory SNS activity (A/A: 313 ± 47 ms(2), A/G: 333 ± 42 ms(2), G/G: 185 ± 23 ms(2), P<0.05). CONCLUSION Diminished REE in G-allele carriers as well as reduced thermoregulatory SNS activity for the G/G genotype, suggest that attenuated UCP1-linked thermogenesis has an adverse effect on the regulation of energy balance.
Collapse
|
13
|
The polymorphisms of UCP1 genes associated with fat metabolism, obesity and diabetes. Mol Biol Rep 2009; 37:1513-22. [PMID: 19444646 DOI: 10.1007/s11033-009-9550-2] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2008] [Accepted: 04/30/2009] [Indexed: 10/20/2022]
Abstract
Uncoupling protein 1 (UCP1), a 32-kDa protein located in the inner mitochondrial membrane, is abundant in brown adipose tissue, as a proton transporter in mitochondria inner membrane which uncouples oxidative metabolism from ATP synthesis and dissipates energy through the heat. UCP1 has been reported to play important roles for energy homeostasis in rodents and neonate of larger mammals including human. Recently, numerous candidate genes were searched to determine the genetic factors implicated in the pathogenesis of obesity, related metabolic disorders and diabetes. UCP-1, which plays a major role in thermogenesis, was suggested to be one of the candidates. This review summarizes data supporting the existence of brown adipocytes and the role of UCP1 in energy dissipation in adult humans, and the genetic variety association with the fat metabolism, obesity and diabetes.
Collapse
|