scholarly journals Functional atrophy of brown adipose tissue during lactation in mice. Effects of lactation and weaning on mitochondrial GDP binding and uncoupling protein

1987 ◽  
Vol 248 (1) ◽  
pp. 273-276 ◽  
Author(s):  
P Trayhurn ◽  
G Jennings

The thermogenic activity and capacity of brown adipose tissue were determined in mice during lactation and after weaning. There was a marked fall during lactation in the mitochondrial content of the tissue, and in GDP binding and the specific mitochondrial concentration of uncoupling protein. The lactation-induced functional atrophy of brown adipose tissue was fully reversible after weaning; mitochondrial content and the mitochondrial concentration of uncoupling protein were both restored, although GDP binding was not normalized.

1987 ◽  
Vol 65 (11) ◽  
pp. 955-959 ◽  
Author(s):  
Hasmukh V. Patel ◽  
Karl B. Freeman ◽  
Michel Desautels

The time course of changes in the level of uncoupling protein mRNA when cold-acclimated mice were returned to a thermoneutral environment (33 °C) was examined using a cDNA probe. Upon deacclimation, there was a marked loss of uncoupling protein mRNA within 24 h, which precedes the loss of uncoupling protein from mitochondria. This loss of uncoupling protein mRNA was selective, since there was no change in the relative proportion of cytochrome c oxidase subunit IV mRNA or poly(A)+ RNA in total RNA. The results suggest that the decrease in the mitochondrial content of uncoupling protein during deacclimation is likely the result of turnover of existing protein, with very little replacement due to a lower level of its mRNA.


2016 ◽  
Vol 311 (2) ◽  
pp. R325-R336 ◽  
Author(s):  
Mallory A. Ballinger ◽  
Clair Hess ◽  
Max W. Napolitano ◽  
James A. Bjork ◽  
Matthew T. Andrews

Brown adipose tissue (BAT) is a thermogenic organ that is vital for hibernation in mammals. Throughout the hibernation season, BAT mitochondrial uncoupling protein 1 (UCP1) enables rapid rewarming from hypothermic torpor to periodic interbout arousals (IBAs), as energy is dissipated as heat. However, BAT's unique ability to rewarm the body via nonshivering thermogenesis is not necessary outside the hibernation season, suggesting a potential seasonal change in the regulation of BAT function. Here, we examined the BAT mitochondrial proteome and mitochondrial bioenergetics in the thirteen-lined ground squirrel ( Ictidomys tridecemlineatus) across four time points: spring, fall, torpor, and IBA. Relative mitochondrial content of BAT was estimated by measuring BAT pad mass, UCP1 protein content, and mitochondrial DNA (mtDNA) copy number. BAT mtDNA content was significantly lower in spring compared with torpor and IBA ( P < 0.05). UCP1 mRNA and protein levels were highest during torpor and IBA. Respiration rates of isolated BAT mitochondria were interrogated at each complex of the electron transport chain. Respiration at complex II was significantly higher in torpor and IBA compared with spring ( P < 0.05), suggesting an enhancement in mitochondrial respiratory capacity during hibernation. Additionally, proteomic iTRAQ labeling identified 778 BAT mitochondrial proteins. Proteins required for mitochondrial lipid translocation and β-oxidation were upregulated during torpor and IBA and downregulated in spring. These data imply that BAT bioenergetics and mitochondrial content are not static across the year, despite the year-round presence of UCP1.


1989 ◽  
Vol 256 (1) ◽  
pp. R42-R48 ◽  
Author(s):  
R. E. Milner ◽  
L. C. Wang ◽  
P. Trayhurn

The thermogenic activity [mitochondrial guanosine 5'-diphosphate (GDP) binding] and capacity (uncoupling protein concentration, cytochrome oxidase activity) of brown adipose tissue have been investigated at different phases of the seasonally linked hibernation cycle in Richardson's ground squirrel. The amount of axillary brown adipose tissue and the total mitochondrial content of the tissue were substantially greater in hibernating squirrels than in squirrels caught posthibernation in April or May; cold acclimation induced qualitatively similar differences. The specific mitochondrial concentration of uncoupling protein was high under all conditions (compared with other species), differing little between hibernating, posthibernating, and cold-acclimated squirrels. The thermogenic capacity of brown adipose tissue in Richardson's ground squirrels is therefore modulated almost exclusively by changes in the mitochondrial content of the tissue. Mitochondrial GDP binding was increased on cold acclimation, but similar binding levels were observed in hibernating and posthibernation (May) animals. GDP binding and the GDP-sensitive component of acetate-induced mitochondrial swelling were increased during the early stages of arousal from hibernation. These changes, which indicate an activation of the thermogenic proton conductance pathway in arousal, occurred without an alteration in the specific mitochondrial concentration of uncoupling protein. Increased GDP binding during arousal is clearly due to the unmasking of binding sites, reflecting an acute activation of preexisting uncoupling protein.


1994 ◽  
Vol 269 (10) ◽  
pp. 7435-7438
Author(s):  
D.L. Murdza-Inglis ◽  
M. Modriansky ◽  
H.V. Patel ◽  
G. Woldegiorgis ◽  
K.B. Freeman ◽  
...  

eLife ◽  
2014 ◽  
Vol 3 ◽  
Author(s):  
Haiying Zhou ◽  
Bo Wan ◽  
Ivan Grubisic ◽  
Tommy Kaplan ◽  
Robert Tjian

Brown adipose tissue (BAT) plays an essential role in metabolic homeostasis by dissipating energy via thermogenesis through uncoupling protein 1 (UCP1). Previously, we reported that the TATA-binding protein associated factor 7L (TAF7L) is an important regulator of white adipose tissue (WAT) differentiation. In this study, we show that TAF7L also serves as a molecular switch between brown fat and muscle lineages in vivo and in vitro. In adipose tissue, TAF7L-containing TFIID complexes associate with PPARγ to mediate DNA looping between distal enhancers and core promoter elements. Our findings suggest that the presence of the tissue-specific TAF7L subunit in TFIID functions to promote long-range chromatin interactions during BAT lineage specification.


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.


1995 ◽  
Vol 268 (1) ◽  
pp. R183-R191 ◽  
Author(s):  
A. M. Strack ◽  
M. J. Bradbury ◽  
M. F. Dallman

Brown adipose tissue (BAT) contains glucocorticoid receptors; glucocorticoids are required for maintaining differentiated BAT in culture. These studies were performed to determine the effects of corticosterone on BAT thermogenic function and lipid storage. Rats were adrenalectomized and given subcutaneous corticosterone pellets in concentrations that maintained plasma corticosterone constant across the range of 0-20 micrograms/dl or were sham adrenalectomized. All variables were examined 5 days after surgery and corticosterone replacement. Measures of BAT function-thermogenic capacity [guanosine 5'-diphosphate (GDP) binding and uncoupling protein (UCP; a BAT-specific thermogenic protein)] and storage (BAT wet wt, protein, and DNA levels) were made. Plasma hormones (corticosterone, adrenocorticotropic hormone, insulin, 3,3',5-triiodothyronine, and thyroxine were measured. Corticosterone significantly affected BAT thermogenic measures: UCP content and binding of GDP to BAT mitochondria decreased with increasing corticosterone; GDP binding characteristics in BAT from similarly prepared rats examined by Scatchard analysis showed that maximum binding (Bmax) and dissociation constant (Kd) decreased with increasing corticosterone dose. BAT DNA was increased by adrenalectomy and maintained at intact levels with all doses of corticosterone; BAT lipid storage increased dramatically at corticosterone values higher than the daily mean level in intact rats. Histologically, the number and size of lipid droplets within BAT adipocytes increased markedly with increased corticosterone. White adipose depots were more sensitive to circulating corticosterone concentrations than were BAT depots and increased in weight at levels of corticosterone that were at or below the daily mean level of intact rats. We conclude that, within its diurnal range of concentration corticosterone acts to inhibit nonshivering thermogenesis and increase lipid storage.(ABSTRACT TRUNCATED AT 250 WORDS)


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