scholarly journals p53 regulates expression of uncoupling protein 1 through binding and repression of PPARγ coactivator-1α

2016 ◽  
Vol 310 (2) ◽  
pp. E116-E128 ◽  
Author(s):  
Philip Hallenborg ◽  
Even Fjære ◽  
Bjørn Liaset ◽  
Rasmus Koefoed Petersen ◽  
Incoronata Murano ◽  
...  

The tumor suppressor p53 (TRP53 in mice) is known for its involvement in carcinogenesis, but work during recent years has underscored the importance of p53 in the regulation of whole body metabolism. A general notion is that p53 is necessary for efficient oxidative metabolism. The importance of UCP1-dependent uncoupled respiration and increased oxidation of glucose and fatty acids in brown or brown-like adipocytes, termed brite or beige, in relation to energy balance and homeostasis has been highlighted recently. UCP1-dependent uncoupled respiration in classic interscapular brown adipose tissue is central to cold-induced thermogenesis, whereas brite/beige adipocytes are of special importance in relation to diet-induced thermogenesis, where the importance of UCP1 is only clearly manifested in mice kept at thermoneutrality. We challenged wild-type and TRP53-deficient mice by high-fat feeding under thermoneutral conditions. Interestingly, mice lacking TRP53 gained less weight compared with their wild-type counterparts. This was related to an increased expression of Ucp1 and other PPARGC1a and PPARGC1b target genes but not Ppargc1a or Ppargc1b in inguinal white adipose tissue of mice lacking TRP53. We show that TRP53, independently of its ability to bind DNA, inhibits the activity of PPARGC1a and PPARGC1b. Collectively, our data show that TRP53 has the ability to regulate the thermogenic capacity of adipocytes through modulation of PPARGC1 activity.

2006 ◽  
Vol 290 (6) ◽  
pp. E1304-E1312 ◽  
Author(s):  
Sheila R. Costford ◽  
Shehla N. Chaudhry ◽  
Mahmoud Salkhordeh ◽  
Mary-Ellen Harper

Uncoupling protein-3 (UCP3) is a poorly understood mitochondrial inner membrane protein expressed predominantly in skeletal muscle. The aim of this study was to examine the effects of the absence or constitutive physiological overexpression of UCP3 on whole body energy metabolism, glucose tolerance, and muscle triglyceride content. Congenic male UCP3 knockout mice ( Ucp3 −/−), wild-type, and transgenic UCP3 overexpressing (UCP3Tg) mice were fed a 10% fat diet for 4 or 8 mo after they were weaned. UCP3Tg mice had lower body weights and were less metabolically efficient than wild-type or Ucp3 −/− mice, but they were not hyperphagic. UCP3Tg mice had smaller epididymal white adipose tissue and brown adipose tissue (BAT) depots; however, there were no differences in muscle weights. Glucose and insulin tolerance tests revealed that both UCP3Tg and Ucp3 −/− mice were protected from development of impaired glucose tolerance and were more sensitive to insulin. 2-Deoxy-d-[1-3H]glucose tracer studies showed increased uptake of glucose into BAT and increased storage of liver glycogen in Ucp3 −/− mice. Assessments of intramuscular triglyceride (IMTG) revealed decreases in quadriceps of UCP3Tg mice compared with wild-type and Ucp3 −/− mice. When challenged with a 45% fat diet, Ucp3 −/− mice showed increased accumulation of IMTG compared with wild-type mice, which in turn had greater IMTG than UCP3Tg mice. Results are consistent with a role for UCP3 in preventing accumulation of triglyceride in both adipose tissue and muscle.


Endocrinology ◽  
2015 ◽  
Vol 156 (3) ◽  
pp. 975-986 ◽  
Author(s):  
Pamela V. Lear ◽  
David González-Touceda ◽  
Begoña Porteiro Couto ◽  
Patricia Viaño ◽  
Vanessa Guymer ◽  
...  

Abstract Intracellular calcium-permeable channels have been implicated in thermogenic function of murine brown and brite/beige adipocytes, respectively transient receptor potential melastin-8 and transient receptor potential vanilloid-4. Because the endo-lysosomal two-pore channels (TPCs) have also been ascribed with metabolic functionality, we studied the effect of simultaneously knocking out TPC1 and TPC2 on body composition and energy balance in male mice fed a chow diet. Compared with wild-type mice, TPC1 and TPC2 double knockout (Tpcn1/2−/−) animals had a higher respiratory quotient and became obese between 6 and 9 months of age. Although food intake was unaltered, interscapular brown adipose tissue (BAT) maximal temperature and lean-mass adjusted oxygen consumption were lower in Tpcn1/2−/− than in wild type mice. Phosphorylated hormone-sensitive lipase expression, lipid density and expression of β-adrenergic receptors were also lower in Tpcn1/2−/− BAT, whereas mitochondrial respiratory chain function and uncoupling protein-1 expression remained intact. We conclude that Tpcn1/2−/− mice show mature-onset obesity due to reduced lipid availability and use, and a defect in β-adrenergic receptor signaling, leading to impaired thermogenic activity, in BAT.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Shasika Jayarathne ◽  
Mandana Pahlavani ◽  
Latha Ramalingam ◽  
Shane Scoggin ◽  
Naima Moustaid-Moussa

Abstract Objectives Brown adipose tissue (BAT) regulates energy balance through thermogenesis, in part via uncoupling protein -1 (UCP-1). White adipose tissue (WAT), namely subcutaneous adipose tissue (SAT) can convert to a beige/brite adipose tissue phenotype (browning) under thermogenic conditions such as cold. We previously reported that eicosapentaenoic acid (EPA) reduced obesity and glucose intolerance, and increased UCP-1 in BAT of B6 mice at ambient temperature (22°C); and these effects were attenuated at thermoneutral environment (28–30°C). We hypothesized that EPA exerts anti-obesity effects on SAT, including increased browning, adipocyte hypotrophy; and these effects require UCP-1. Methods Six-week-old B6 wild type (WT) and UCP-1 knock-out (KO) male mice were maintained at thermoneutral environment and fed high fat diet (HF) with or without 36 g/kg of AlaskOmega EPA-enriched fish oil (800 mg/g) for 14 weeks; and SAT was collected for histological, gene and protein analyses. SAT was also prepared from chow diet-fed WT and KO mice at ambient environment to prepare stroma vascular cells, which were differentiated into adipocytes, treated with 100uM EPA for 48 hours then harvested for mRNA and protein analyses. Results KO mice fed HF diets had the highest body weight (P < 0.05) among all groups. EPA reduced fat cell size in both WT and KO mice fed the EPA diet. mRNA levels of fibroblast growth factor-21 (FGF-21) were higher in SAT of WT mice fed EPA compared to WT mice fed HF (P < 0.05), with no differences between the KO genotype. KO mice fed HF diets had lower levels of UCP-3 in SAT compared to WT mice fed HF (P < 0.05), which was rescued only in the KO mice fed EPA (P < 0.05). UCP-1 protein levels were very low in SAT tissues, and UCP-2 mRNA levels were similar across all groups in SAT. Interestingly, EPA significantly (P < 0.05) increased mRNA expression of UCP-2, UCP-3 and FGF21 in differentiated SAT adipocytes from both WT and KO compared to control. Furthermore, UCP-1 mRNA levels were significantly higher in WT adipocytes treated with EPA, compared to non-treated cells (P < 0.05). Additional mechanistic studies are currently underway to further dissect adipose depot differences in EPA effects in WT vs. KO mice. Conclusions Our data suggest that EPA increases SAT browning, independently of UCP-1. Funding Sources NIH/NCCIH.


2021 ◽  
Author(s):  
Mingsheng Ye ◽  
Liping Luo ◽  
Qi Guo ◽  
Guanghua Lei ◽  
Chao Zeng ◽  
...  

Brown adipose tissue (BAT) is emerging as a target to beat obesity through the dissipation of chemical energy to heat. However, the molecular mechanisms of brown adipocyte thermogenesis remain to be further elucidated. Here, we show that KCTD10, a member of the polymerase delta-interacting protein 1 (PDIP1) family, was reduced in BAT by cold stress and a β3 adrenoceptor agonist. Moreover, KCTD10 level increased in the BAT of obese mice, and KCTD10 overexpression attenuates uncoupling protein 1 (UCP1) expression in primary brown adipocytes. BAT-specific KCTD10 knockdown mice had increased thermogenesis and cold tolerance protecting from high fat diet (HFD)-induced obesity. Conversely, overexpression of KCTD10 in BAT caused reduced thermogenesis, cold intolerance, and obesity. Mechanistically, inhibiting Notch signaling restored the KCTD10 overexpression suppressed thermogenesis. Our study presents that KCTD10 serves as an upstream regulator of notch signaling pathway to regulate BAT thermogenesis and whole-body metabolic function.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Clarissa S. Craft ◽  
Hero Robles ◽  
Madelyn R. Lorenz ◽  
Eric D. Hilker ◽  
Kristann L. Magee ◽  
...  

AbstractAdipocytes within the skeleton are collectively termed bone marrow adipose tissue (BMAT). BMAT contributes to peripheral and local metabolism, however, its capacity for cell-autonomous expression of uncoupling protein 1 (UCP1), a biomarker of beige and brown adipogenesis, remains unclear. To overcome this, Ucp1-Cre was used to drive diphtheria toxin expression in cells expressing UCP1 (Ucp1Cre+/DTA+). Despite loss of brown adipose tissue, BMAT volume was not reduced in Ucp1Cre+/DTA+ mice. Comparably, in mTmG reporter mice (Ucp1Cre+/mTmG+), Ucp1-Cre expression was absent from BMAT in young (3-weeks) and mature (16-weeks) male and female mice. Further, β3-agonist stimulation failed to induce Ucp1-Cre expression in BMAT. This demonstrates that BMAT adipocytes are not UCP1-expressing beige/brown adipocytes. Thus, to identify novel and emerging roles for BMAT adipocytes in skeletal and whole-body homeostasis, we performed gene enrichment analysis of microarray data from adipose tissues of adult rabbits. Pathway analysis revealed genetic evidence for differences in BMAT including insulin resistance, decreased fatty acid metabolism, and enhanced contributions to local processes including bone mineral density through candidate genes such as osteopontin. In sum, this supports a paradigm by which BMAT adipocytes are a unique subpopulation that is specialized to support cells within the skeletal and hematopoietic niche.


1993 ◽  
Vol 291 (1) ◽  
pp. 109-113 ◽  
Author(s):  
R Burcelin ◽  
J Kande ◽  
D Ricquier ◽  
J Girard

We have studied the time course and relative effects of hypoinsulinaemia and hyperglycaemia on concentrations of uncoupling protein (UCP) and glucose transporter (GLUT4) and their mRNAs in brown adipose tissue (BAT) during the early phase of diabetes induced by streptozotocin. Two days after intravenous injection of streptozotocin, plasma insulin concentration was at its lowest and glycaemia was higher than 22 mmol/l. After 3 days, a 60% decrease in BAT UCP mRNA concentration and a 36% decrease in UCP was observed. Concomitantly, there was an 80% decrease in GLUT4 mRNA and a 44% decrease in GLUT4 levels. When hyperglycaemia was prevented by infusing phlorizin into diabetic rats, BAT UCP mRNA and protein levels were further decreased (respectively 90% and 60% lower than in control rats). In contrast, the marked decreases in GLUT4 mRNA and protein concentrations in BAT were similar in hyperglycaemic and normoglycaemic diabetic rats. Infusion of physiological amounts of insulin restored normoglycaemia in diabetic rats, and BAT UCP and GLUT4 mRNA and protein concentrations were maintained at the level of control rats. When insulin infusion was stopped, a 75% decrease in BAT UCP mRNA level and a 75% decrease in GLUT4 mRNA level were observed after 24 h, but UCP and GLUT4 concentrations did not decrease. This study shows that insulin plays an important role in the regulation of UCP and GLUT4 mRNA and protein concentrations in BAT. Hyperglycaemia partially prevents the rapid decrease in concentration of UCP and its mRNA observed in insulinopenic diabetes whereas it did not affect the decrease in GLUT4 mRNA and protein concentration. It is suggested that UCP is produced by a glucose-dependent gene.


2019 ◽  
Vol 51 (10) ◽  
pp. 678-685 ◽  
Author(s):  
Luka Levata ◽  
Riccardo Dore ◽  
Olaf Jöhren ◽  
Markus Schwaninger ◽  
Carla Schulz ◽  
...  

AbstractNesfatin-1 has originally been established as a bioactive peptide interacting with key hypothalamic nuclei and neural circuitries in control of feeding behavior, while its effect on energy expenditure has only recently been investigated. Hence, the aim of this study was to examine whether centrally acting nesfatin-1 can induce β3-adrenergic stimulation, which is a prerequisite for the activation of thermogenic genes and heat release from interscapular brown adipose tissue, key physiological features that underlie increased energy expenditure. This question was addressed in non-fasted mice stereotactically cannulated to receive nesfatin-1 intracerebroventricularly together with peripheral injection of the β3-adrenoceptor antagonist SR 59230 A, to assess whole-body energy metabolism. Using a minimally invasive thermography technique, we now demonstrate that the thermogenic effect of an anorectic nesfatin-1 dose critically depends on β3 adrenergic stimulation, as the co-administration with SR 59230 A completely abolished heat production from interscapular brown adipose tissue and rise in ocular surface temperature, thus preventing body weight loss. Moreover, through indirect calorimetry it could be shown that the anorectic concentration of nesfatin-1 augments overall caloric expenditure. Plausibly, central administration of nesfatin-1 also enhanced the expression of DIO2 and CIDEA mRNA in brown adipose tissue critically involved in the regulation of thermogenesis.


2010 ◽  
Vol 298 (3) ◽  
pp. E548-E554 ◽  
Author(s):  
Rickard Westergren ◽  
Daniel Nilsson ◽  
Mikael Heglind ◽  
Zahra Arani ◽  
Mats Grände ◽  
...  

Many members of the forkhead genes family of transcription factors have been implicated as important regulators of metabolism, in particular, glucose homeostasis, e.g., Foxo1, Foxa3, and Foxc2. The purpose of this study was to exploit the possibility that yet unknown members of this gene family play a role in regulating glucose tolerance in adipocytes. We identified Foxf2 in a screen for adipose-expressed forkhead genes. In vivo overexpression of Foxf2 in an adipose tissue-restricted fashion demonstrated that such mice display a significantly induced insulin secretion in response to an intravenous glucose load compared with wild-type littermates. In response to increased Foxf2 expression, insulin receptor substrate 1 (IRS1) mRNA and protein levels are significantly downregulated in adipocytes; however, the ratio of serine vs. tyrosine phosphorylation of IRS1 seems to remain unaffected. Furthermore, adipocytes overexpressing Foxf2 have a significantly lower insulin-mediated glucose uptake compared with wild-type adipocytes. These findings argue that Foxf2 is a previously unrecognized regulator of cellular and systemic whole body glucose tolerance, at least in part, due to lower levels of IRS1. Foxf2 and its downstream target genes can provide new insights with regard to identification of novel therapeutic targets.


1987 ◽  
Vol 252 (1) ◽  
pp. R160-R165 ◽  
Author(s):  
C. J. Billington ◽  
T. J. Bartness ◽  
J. Briggs ◽  
A. S. Levine ◽  
J. E. Morley

Despite long-standing observations of a whole-body thermogenic effect of glucagon, the role of glucagon in activating thermogenesis in brown adipose tissue has not often been studied. We investigated the ability of administered glucagon to produce alterations in brown adipose tissue similar to changes produced by accepted stimuli of brown fat activity: cold, norepinephrine, and overfeeding. Eighteen days of glucagon injections (1 mg/kg) to male Sprague-Dawley rats produced, relative to saline-injected controls, decreases in feed efficiency and increases in brown adipose tissue weight, protein content, DNA content, and mitochondrial mass as reflected in cytochrome oxidase activity. The observed changes were similar, though of lesser magnitude, to changes produced in these same parameters induced by administration of norepinephrine (250 micrograms/kg) for a positive control group. Four days of glucagon administration (1 mg/kg) produced increases in specific activity of cytochrome oxidase and lipoprotein lipase. After 8 days of glucagon administration, changes in whole-pad activity similar to those seen with 18 days of administration were present. Glucagon also increased whole-pad lipoprotein lipase activity after 4 and 8 days. Surgically denervated interscapular brown adipose tissue retained its ability to respond to exogenous glucagon, though the magnitude of the response was diminished. Guanosine 5'-diphosphate (GDP) binding to brown adipose tissue mitochondria was measured as an assessment of functional state after 5 days of glucagon (1 mg/kg). There was an increase in GDP binding relative to controls whether expressed as picomoles per milligram mitochondrial protein or nanomoles per pad.(ABSTRACT TRUNCATED AT 250 WORDS)


2011 ◽  
Vol 301 (2) ◽  
pp. R473-R483 ◽  
Author(s):  
Jake D. Bauwens ◽  
Eric G. Schmuck ◽  
Christopher R. Lindholm ◽  
Rebecca L. Ertel ◽  
Jacob D. Mulligan ◽  
...  

Recent studies indicate that a substantial amount of metabolically active brown adipose tissue (BAT) exists in adult humans. Given the unique ability of BAT to convert calories to heat, there is intense interest in understanding the regulation of BAT metabolism in hopes that its manipulation might be an effective way of expending excess calories. Because of the established role of AMP-activated protein kinase (AMPK) as a “metabolic master switch” and its extremely high levels of activity in BAT, it was hypothesized that AMPK might play a central role in regulating BAT metabolism. To test this hypothesis, whole body α1-AMPK−/− (knockout) and wild-type mice were studied 1) under control (room temperature) conditions, 2) during chronic cold exposure (14 days at 4°C), and 3) during acute nonshivering thermogenesis (injection of a β3-adrenergic agonist). Under control conditions, loss of α1-AMPK resulted in downregulation of two important prothermogenic genes in BAT, thyrotropin-releasing hormone (−9.2-fold) and ciliary neurotrophic factor (−8.7-fold). Additionally, it caused significant upregulation of α2-AMPK activity in BAT, white adipose tissue, and liver, but not cardiac or skeletal muscle. During acute nonshivering thermogenesis and chronic cold exposure, body temperature was indistinguishable in the α1-AMPK−/− and wild-type mice. Similarly, the degree of cold-induced hyperphagia was identical in the two groups. We conclude that α1-AMPK does not play an obligatory role in these processes and that adaptations to chronic loss of α1-AMPK are able to compensate for its loss via several mechanisms.


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