scholarly journals Immunohistochemical identification of the uncoupling protein in rat brown adipose tissue.

1985 ◽  
Vol 33 (2) ◽  
pp. 150-154 ◽  
Author(s):  
M Cadrin ◽  
M Tolszczuk ◽  
J Guy ◽  
G Pelletier ◽  
K B Freeman ◽  
...  

Brown adipose tissue mitochondria are characterized by the presence of an uncoupling protein that gives them an exceptional capacity for substrate-controlled respiration and thermogenesis. The specific localization of this protein in rat brown adipocytes was demonstrated using an immunohistochemical technique, the peroxidase-antiperoxidase (PAP) method. Light microscopy observations showed that serum antibodies raised against the uncoupling protein selectively reacted with multilocular brown adipocytes. No labeling could be detected in either unilocular adipocytes, capillaries, or muscle fibers (striated and vascular smooth muscle). Staining was more intensive in certain adipocytes than in others, suggesting the presence of cellular heterogeneity. The specificity of the staining technique was demonstrated by showing that treatment of the preparations with antiserum saturated with an excess of uncoupling protein almost entirely inhibited brown adipocyte labeling. The specificity and selectivity of the PAP method allow the clear differentiation of uncoupling protein-containing adipocytes from other cellular types, suggesting that this immunohistochemical technique will represent an extremely useful tool for studying adipocyte function and differentiation.

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 317 (5) ◽  
pp. E742-E750 ◽  
Author(s):  
Tania Quesada-López ◽  
Aleix Gavaldà-Navarro ◽  
Samantha Morón-Ros ◽  
Laura Campderrós ◽  
Roser Iglesias ◽  
...  

Adaptive induction of thermogenesis in brown adipose tissue (BAT) is essential for the survival of mammals after birth. We show here that G protein-coupled receptor protein 120 (GPR120) expression is dramatically induced after birth in mouse BAT. GPR120 expression in neonatal BAT is the highest among GPR120-expressing tissues in the mouse at any developmental stage tested. The induction of GPR120 in neonatal BAT is caused by postnatal thermal stress rather than by the initiation of suckling. GPR120-null neonates were found to be relatively intolerant to cold: close to one-third did not survive at 21°C, but all such pups survived at 25°C. Heat production in BAT was significantly impaired in GPR120-null pups. Deficiency in GPR120 did not modify brown adipocyte morphology or the anatomical architecture of BAT, as assessed by electron microscopy, but instead impaired the expression of uncoupling protein-1 and the fatty acid oxidation capacity of neonatal BAT. Moreover, GPR120 deficiency impaired fibroblast growth factor 21 (FGF21) gene expression in BAT and reduced plasma FGF21 levels. These results indicate that GPR120 is essential for neonatal adaptive thermogenesis.


1994 ◽  
Vol 302 (3) ◽  
pp. 695-700 ◽  
Author(s):  
C Manchado ◽  
P Yubero ◽  
O Viñas ◽  
R Iglesias ◽  
F Villarroya ◽  
...  

CCAAT/enhancer-binding protein (C/EBP) alpha mRNA and its protein products C/EBP alpha and 30 kDa C/EBP alpha are expressed in rat brown-adipose tissue. Results also demonstrate the expression of C/EBP beta mRNA and its protein products C/EBP beta and liver inhibitory protein (LIP) in the tissue. The abundance of C/EBP alpha and C/EBP beta proteins in adult brown fat is similar to that found in adult liver. However, the expression of C/EBP alpha and C/EBP beta is specifically regulated in brown fat during development. C/EBP alpha, 30 kDa C/EBP alpha, C/EBP beta and LIP content is several-fold higher in fetal brown fat than in the adult tissue, or liver at any stage of development. Peak values are attained in late fetal life, in concurrence with the onset of transcription of the uncoupling protein (UCP) gene, the molecular marker of terminal brown-adipocyte differentiation. When adult rats are exposed to a cold environment, which is a physiological stimulus of brown-adipose tissue hyperplasia and UCP gene expression, a specific rise in C/EBP beta expression with respect to C/EBP alpha, 30 kDa C/EBP alpha and LIP is observed. Present data suggest that the C/EBP family of transcription factors has an important role in the development and terminal differentiation of brown-adipose tissue.


2011 ◽  
Vol 300 (1) ◽  
pp. R1-R8 ◽  
Author(s):  
Tobias Fromme ◽  
Martin Klingenspor

Uncoupling protein 1 (Ucp1) is the key component of β-adrenergically controlled nonshivering thermogenesis in brown adipocytes. This process combusts stored and nutrient energy as heat. Cold exposure not only activates Ucp1-mediated thermogenesis to maintain normothermia but also results in adaptive thermogenesis, i.e., the recruitment of thermogenic capacity in brown adipose tissue. As a hallmark of adaptive thermogenesis, Ucp1 synthesis is increased proportionally to temperature and duration of exposure. Beyond this classical thermoregulatory function, it has been suggested that Ucp1-mediated thermogenesis can also be employed for metabolic thermogenesis to prevent the development of obesity. Accordingly, in times of excess caloric intake, one may expect a positive regulation of Ucp1. The general impression from an overview of the present literature is, indeed, an increased brown adipose tissue Ucp1 mRNA and protein content after feeding a high-fat diet (HFD) to mice and rats. The reported increases are very variable in magnitude, and the effect size seems to be independent of dietary fat content and duration of the feeding trial. In white adipose tissue depots Ucp1 mRNA is generally downregulated by HFD, indicating a decline in the number of interspersed brown adipocytes.


1989 ◽  
Vol 263 (2) ◽  
pp. 341-345 ◽  
Author(s):  
J A Woodward ◽  
E D Saggerson

1. Rats were made hypothyroid by giving them a low-iodine diet with propylthiouracil for 4 weeks, or were made hyperthyroid by injection with tri-iodothyronine (T3) over a 3-day period. 2. Brown adipocytes were isolated from the interscapular depots of these animals or from their euthyroid controls, followed by isolation of mitochondria from the cells. 3. Relative to cell DNA content, hypothyroidism decreased the maximum binding (Bmax.) of [3H]GDP to mitochondria by 50%. T3 treatment increased binding by 37%. 4. These findings, which are discussed in relation to previously observed changes in brown adipose tissue after alteration of thyroid status, suggest that mitochondrial uncoupling for thermogenesis is less or more effective in hypothyroidism or hyperthyroidism respectively.


2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Umesh D. Wankhade ◽  
Michael Shen ◽  
Hariom Yadav ◽  
Keshari M. Thakali

Nonshivering thermogenesis is the process of biological heat production in mammals and is primarily mediated by brown adipose tissue (BAT). Through ubiquitous expression of uncoupling protein 1 (Ucp1) on the mitochondrial inner membrane, BAT displays uncoupling of fuel combustion and ATP production in order to dissipate energy as heat. Because of its crucial role in regulating energy homeostasis, ongoing exploration of BAT has emphasized its therapeutic potential in addressing the global epidemics of obesity and diabetes. The recent appreciation that adult humans possess functional BAT strengthens this prospect. Furthermore, it has been identified that there are both classical brown adipocytes residing in dedicated BAT depots and “beige” adipocytes residing in white adipose tissue depots that can acquire BAT-like characteristics in response to environmental cues. This review aims to provide a brief overview of BAT research and summarize recent findings concerning the physiological, cellular, and developmental characteristics of brown adipocytes. In addition, some key genetic, molecular, and pharmacologic targets of BAT/Beige cells that have been reported to have therapeutic potential to combat obesity will be discussed.


1999 ◽  
Vol 345 (1) ◽  
pp. 91-97 ◽  
Author(s):  
Rosa ALVAREZ ◽  
MaLuz CHECA ◽  
Sonia BRUN ◽  
Octavi VI±AS ◽  
Teresa MAMPEL ◽  
...  

The intracellular pathways and receptors mediating the effects of retinoic acid (RA) on the brown-fat-uncoupling-protein-1 gene (ucp-1) have been analysed. RA activates transcription of ucp-1 and the RA receptor (RAR) is known to be involved in this effect. However, co-transfection of an expression vector for retinoid-X receptor (RXR) increases the action of 9-cis RA but not the effects of all-trans RA on the ucp-1 promoter in brown adipocytes. Either RAR-specific {p-[(E)-2-(5,6,7,8,-tetrahydro-5,5,8,8-tetramethyl-2-naphthalenyl)-1-propenyl]benzoic acid} or RXR-specific [isopropyl-(E,E)-(R,S)-11-methoxy-3,7,11-trimethyldodeca-2,4-dienoate, or methoprene] synthetic compounds increase the expression of UCP-1 mRNA and the activity of chloramphenicol acetyltransferase expression vectors driven by the ucp-1 promoter. The RXR-mediated action of 9-cis RA requires the upstream enhancer region at -2469/-2318 in ucp-1. During brown-adipocyte differentiation RXRα and RXRγ mRNA expression is induced in parallel with UCP-1 mRNA, whereas the mRNA for the three RAR subtypes, α, β and γ, decreases. Co-transfection of murine expression vectors for the different RAR and RXR subtypes indicates that RARα and RARβ as well as RXRα are the major retinoid-receptor subtypes capable of mediating the responsiveness of ucp-1 to retinoids. It is concluded that the effects of retinoids on ucp-1 transcription involve both RAR- and RXR-dependent signalling pathways. The responsiveness of brown adipose tissue to retinoids in vivo relies on a complex combination of the capacity of RAR and RXR subtypes to mediate ucp-1 induction and their distinct expression in the differentiated brown adipocyte.


Endocrinology ◽  
2001 ◽  
Vol 142 (3) ◽  
pp. 1195-1201 ◽  
Author(s):  
Masami Murakami ◽  
Yuji Kamiya ◽  
Tadashi Morimura ◽  
Osamu Araki ◽  
Makoto Imamura ◽  
...  

1987 ◽  
Vol 243 (2) ◽  
pp. 617-620 ◽  
Author(s):  
C Roncero ◽  
M Lorenzo ◽  
M Benito

Rates of lipogenesis in foetal isolated brown adipocytes from 22-day-pregnant rats were significantly increased by lactate plus pyruvate as major substrates in the incubation medium, in comparison with the endogenous rates. Insulin stimulated foetal brown-adipocyte lipogenesis, and adrenaline or noradrenaline and isoprenaline decreased lipogenesis. Glucagon had no effect on the lipogenic rate in brown adipocytes. Progesterone administration to the mother significantly increased the rates of lipogenesis in brown adipose tissue and in isolated brown adipocytes from 22-day foetuses. Prolongation of gestation by progesterone to day 23 decreased the rates of brown-adipose-tissue lipogenesis in vivo and in isolated cells in the post-mature foetuses.


1998 ◽  
Vol 331 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Josep A. VILLENA ◽  
Octavi VIÑAS ◽  
Teresa MAMPEL ◽  
Roser IGLESIAS ◽  
Marta GIRALT ◽  
...  

The regulation of transcription of the gene for the β subunit of the FoF1 ATP synthase (ATPsynβ) in brown adipose tissue has been studied as a model to determine the molecular mechanisms for mitochondrial biogenesis associated with brown adipocyte differentiation. The expression of the ATPsynβ mRNA is induced during the brown adipocyte differentiation that occurs during murine prenatal development or when brown adipocytes differentiate in culture. This induction occurs in parallel with enhanced gene expression for other nuclear and mitochondrially-encoded components of the respiratory chain/oxidative phosphorylation system (OXPHOS). Transient transfection assays indicated that the expression of the ATPsynβ gene promoter is higher in differentiated HIB-1B brown adipocytes than in non-differentiated HIB-1B cells. A major transcriptional regulatory site was identified between nt -306 and -266 in the ATPsynβ promoter. This element has a higher enhancer capacity in differentiated brown adipocyte HIB-1B cells than in non-differentiated cells. Electrophoretic shift analysis indicated that Sp1and nuclear respiratory factor-2/GA-binding protein (NRF2/GABP) were the main nuclear proteins present in brown adipose tissue that bind this site. Double-point mutant analysis indicated a major role for the NRF2/GABP site in the enhancer capacity of this element in brown fat cells. It is proposed that NRF2/GABP plays a pivotal role in the co-ordinated enhancement of OXPHOS gene expression associated with mitochondrial biogenesis in brown adipocyte differentiation.


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