Brown adipose tissue in cetacean blubber.
Brown adipose tissue (BAT) plays an important role in thermoregulation in species living in cold environments, given heat can be generated from its chemical energy reserves. Here we investigate the existence of BAT in blubber in four species of delphinoid cetacean, the Pacific white-sided and bottle...
Main Authors: | , , , , , , , , , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
Public Library of Science (PLoS)
2015-01-01
|
Series: | PLoS ONE |
Online Access: | http://europepmc.org/articles/PMC4342347?pdf=render |
id |
doaj-4d4499eaef2b450b8718af24c9cb7f25 |
---|---|
record_format |
Article |
spelling |
doaj-4d4499eaef2b450b8718af24c9cb7f252020-11-24T21:49:08ZengPublic Library of Science (PLoS)PLoS ONE1932-62032015-01-01102e011673410.1371/journal.pone.0116734Brown adipose tissue in cetacean blubber.Osamu HashimotoHirofumi OhtsukiTakehiko KakizakiKento AmouRyo SatoSatoru DoiSara KobayashiAyaka MatsudaMakoto SugiyamaMasayuki FunabaTakashi MatsuishiFumio TerasawaJunji ShindoHideki EndoBrown adipose tissue (BAT) plays an important role in thermoregulation in species living in cold environments, given heat can be generated from its chemical energy reserves. Here we investigate the existence of BAT in blubber in four species of delphinoid cetacean, the Pacific white-sided and bottlenose dolphins, Lagenorhynchus obliquidens and Tursiops truncates, and Dall's and harbour porpoises, Phocoenoides dalli and Phocoena phocoena. Histology revealed adipocytes with small unilocular fat droplets and a large eosinophilic cytoplasm intermingled with connective tissue in the innermost layers of blubber. Chemistry revealed a brown adipocyte-specific mitochondrial protein, uncoupling protein 1 (UCP1), within these same adipocytes, but not those distributed elsewhere throughout the blubber. Western blot analysis of extracts from the inner blubber layer confirmed that the immunohistochemical positive reaction was specific to UCP1 and that this adipose tissue was BAT. To better understand the distribution of BAT throughout the entire cetacean body, cadavers were subjected to computed tomography (CT) scanning. Resulting imagery, coupled with histological corroboration of fine tissue structure, revealed adipocytes intermingled with connective tissue in the lowest layer of blubber were distributed within a thin, highly dense layer that extended the length of the body, with the exception of the rostrum, fin and fluke regions. As such, we describe BAT effectively enveloping the cetacean body. Our results suggest that delphinoid blubber could serve a role additional to those frequently attributed to it: simple insulation blanket, energy storage, hydrodynamic streamlining or contributor to positive buoyancy. We believe delphinoid BAT might also function like an electric blanket, enabling animals to frequent waters cooler than blubber as an insulator alone might otherwise allow an animal to withstand, or allow animals to maintain body temperature in cool waters during sustained periods of physical inactivity.http://europepmc.org/articles/PMC4342347?pdf=render |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Osamu Hashimoto Hirofumi Ohtsuki Takehiko Kakizaki Kento Amou Ryo Sato Satoru Doi Sara Kobayashi Ayaka Matsuda Makoto Sugiyama Masayuki Funaba Takashi Matsuishi Fumio Terasawa Junji Shindo Hideki Endo |
spellingShingle |
Osamu Hashimoto Hirofumi Ohtsuki Takehiko Kakizaki Kento Amou Ryo Sato Satoru Doi Sara Kobayashi Ayaka Matsuda Makoto Sugiyama Masayuki Funaba Takashi Matsuishi Fumio Terasawa Junji Shindo Hideki Endo Brown adipose tissue in cetacean blubber. PLoS ONE |
author_facet |
Osamu Hashimoto Hirofumi Ohtsuki Takehiko Kakizaki Kento Amou Ryo Sato Satoru Doi Sara Kobayashi Ayaka Matsuda Makoto Sugiyama Masayuki Funaba Takashi Matsuishi Fumio Terasawa Junji Shindo Hideki Endo |
author_sort |
Osamu Hashimoto |
title |
Brown adipose tissue in cetacean blubber. |
title_short |
Brown adipose tissue in cetacean blubber. |
title_full |
Brown adipose tissue in cetacean blubber. |
title_fullStr |
Brown adipose tissue in cetacean blubber. |
title_full_unstemmed |
Brown adipose tissue in cetacean blubber. |
title_sort |
brown adipose tissue in cetacean blubber. |
publisher |
Public Library of Science (PLoS) |
series |
PLoS ONE |
issn |
1932-6203 |
publishDate |
2015-01-01 |
description |
Brown adipose tissue (BAT) plays an important role in thermoregulation in species living in cold environments, given heat can be generated from its chemical energy reserves. Here we investigate the existence of BAT in blubber in four species of delphinoid cetacean, the Pacific white-sided and bottlenose dolphins, Lagenorhynchus obliquidens and Tursiops truncates, and Dall's and harbour porpoises, Phocoenoides dalli and Phocoena phocoena. Histology revealed adipocytes with small unilocular fat droplets and a large eosinophilic cytoplasm intermingled with connective tissue in the innermost layers of blubber. Chemistry revealed a brown adipocyte-specific mitochondrial protein, uncoupling protein 1 (UCP1), within these same adipocytes, but not those distributed elsewhere throughout the blubber. Western blot analysis of extracts from the inner blubber layer confirmed that the immunohistochemical positive reaction was specific to UCP1 and that this adipose tissue was BAT. To better understand the distribution of BAT throughout the entire cetacean body, cadavers were subjected to computed tomography (CT) scanning. Resulting imagery, coupled with histological corroboration of fine tissue structure, revealed adipocytes intermingled with connective tissue in the lowest layer of blubber were distributed within a thin, highly dense layer that extended the length of the body, with the exception of the rostrum, fin and fluke regions. As such, we describe BAT effectively enveloping the cetacean body. Our results suggest that delphinoid blubber could serve a role additional to those frequently attributed to it: simple insulation blanket, energy storage, hydrodynamic streamlining or contributor to positive buoyancy. We believe delphinoid BAT might also function like an electric blanket, enabling animals to frequent waters cooler than blubber as an insulator alone might otherwise allow an animal to withstand, or allow animals to maintain body temperature in cool waters during sustained periods of physical inactivity. |
url |
http://europepmc.org/articles/PMC4342347?pdf=render |
work_keys_str_mv |
AT osamuhashimoto brownadiposetissueincetaceanblubber AT hirofumiohtsuki brownadiposetissueincetaceanblubber AT takehikokakizaki brownadiposetissueincetaceanblubber AT kentoamou brownadiposetissueincetaceanblubber AT ryosato brownadiposetissueincetaceanblubber AT satorudoi brownadiposetissueincetaceanblubber AT sarakobayashi brownadiposetissueincetaceanblubber AT ayakamatsuda brownadiposetissueincetaceanblubber AT makotosugiyama brownadiposetissueincetaceanblubber AT masayukifunaba brownadiposetissueincetaceanblubber AT takashimatsuishi brownadiposetissueincetaceanblubber AT fumioterasawa brownadiposetissueincetaceanblubber AT junjishindo brownadiposetissueincetaceanblubber AT hidekiendo brownadiposetissueincetaceanblubber |
_version_ |
1725889267935215616 |