Thyroid hormones and browning of adipose tissue

[helvella]

Brown Adipose Tissue (BAT) is a very interesting substance in humans. It is well-known in animals, and babies, where it acheives non-shivering thermogenesis. Wiki actually explains it rather better, and has some pictures!

en.wikipedia.org/wiki/Therm...

Trouble is, there was quite a long period in which BAT was ignored in adult humans. Even to the point of suggesting that we adults don't have any BAT.

At heart, though, this is an inkling as to how thyroid hormones actually affect body temperature and particularly the ability to cope with cold.

Mol Cell Endocrinol. 2017 Jan 12. pii: S0303-7207(17)30015-1. doi: 10.1016/j.mce.2017.01.011. [Epub ahead of print]

Thyroid hormones and browning of adipose tissue.

Weiner J1, Hankir M1, Heiker JT1, Fenske W1, Krause K2.

Author information

1Department of Endocrinology and Nephrology, University Hospital, Leipzig, Germany.

2Department of Endocrinology and Nephrology, University Hospital, Leipzig, Germany. Electronic address: [e-mail].

Abstract

Thyroid hormone (TH) disorders are associated with profound changes in whole body energy metabolism. A major TH target is thermogenic brown adipose tissue (BAT), which can be stimulated directly through thyroid hormone receptors (TRs) expressed in brown adipocytes and indirectly, through TRs expressed in hypothalamic neurons. White adipose tissue (WAT) adopts BAT characteristics by a diverse range of stimuli in a process referred to as browning. It is now understood that TH also induce WAT browning through peripheral and central mechanisms. In this review, we discuss evidence from animal and human studies that TH disorders are associated with changes in both BAT thermogenesis and WAT browning, thereby influencing body temperature and body weight regulation.

Copyright © 2017. Published by Elsevier B.V.

PMID: 28089823

DOI: 10.1016/j.mce.2017.01.011

ncbi.nlm.nih.gov/pubmed/280...

[shaws Administrator]

I think doctors/endos should read this as well. At one time our temperature used to be taken but I doubt any of us on this forum have doctors who do so.

[nickym1 in reply to shaws]

Following treatment for thyroid cancer, my basal temperature was often below 36, and I felt very poorly. When trying to discuss this with consultant, he scoffed that it would be remiss of him to take body temperature into account when prescribing meds!

Luckily it all improved (somewhat) with adding T3 to the regime.

[shaws Administrator in reply to nickym1]

The tuition in thyroid hormones to medical students and the importance of these hormones are woeful and we suffer even more particularly with your condition.

The old-fashioned doctors now retired treated us on clinical symptoms alone and we had a trial, at least of hormones, and if we felt better we continued. With your condition it is even more important you are adequately prescribed and T3 given but maybe you need a little more T3 to be well.

[LAHs]

Is this BAT the same as Mucin? Mucin is also brown and in an article I read it is supposed to be the "heavy" tissue that we accumulate when we are not on the correct dose of thyroid meds. It is the reason why we cannot get rid of this material through diet and excersize because it is not true "fat". It may also be the reason why raising T3 can burn this stuff up but nothing else can.

Sorry if this question is a bit unscientific but it is the color brown that got me thinking.

[helvella Administrator Thyroid UK in reply to LAHs]

No - mucin is made of glycosylated proteins which form a gel.

BAT is a tissue formed of living cells each with actual fat within them. (There is also White Adipose Tissue and various names for inbetween tissue with arguments still going on about precisely what is what.)

en.wikipedia.org/wiki/Brown...

[helvella Administrator Thyroid UK in reply to LAHs]

nature.com/nm/journal/v19/n...

[LAHs in reply to helvella]

Thanks helvella, this is great info but I will have to study it in more depth - when I have finished my income tax.