Abstract

To elucidate factors underlying the evolution of large brains in cetaceans, we examined 16 brains from 14 cetartiodactyl species, with immunohistochemical techniques, for evidence of non-shivering thermogenesis. We show that, in comparison to the 11 artiodactyl brains studied (from 11 species), the 5 cetacean brains (from 3 species), exhibit an expanded expression of uncoupling protein 1 (UCP1, UCPs being mitochondrial inner membrane proteins that dissipate the proton gradient to generate heat) in cortical neurons, immunolocalization of UCP4 within a substantial proportion of glia throughout the brain, and an increased density of noradrenergic axonal boutons (noradrenaline functioning to control concentrations of and activate UCPs). Thus, cetacean brains studied possess multiple characteristics indicative of intensified thermogenetic functionality that can be related to their current and historical obligatory aquatic niche. These findings necessitate reassessment of our concepts regarding the reasons for large brain evolution and associated functional capacities in cetaceans.

Details

Title
Amplification of potential thermogenetic mechanisms in cetacean brains compared to artiodactyl brains
Author
Manger, Paul R 1 ; Patzke Nina 2 ; Spocter, Muhammad A 3 ; Bhagwandin Adhil 4 ; Karlsson, Karl Æ 5 ; Bertelsen, Mads F 6 ; Alagaili, Abdulaziz N 7 ; Bennett, Nigel C 8 ; Mohammed, Osama B 7 ; Herculano-Houzel Suzana 9 ; Hof, Patrick R 10 ; Fuxe Kjell 11 

 University of the Witwatersrand, School of Anatomical Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135) 
 University of the Witwatersrand, School of Anatomical Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); Hokkaido University, Institute for the Advancement of Higher Education, Sapporo, Japan (GRID:grid.39158.36) (ISNI:0000 0001 2173 7691) 
 University of the Witwatersrand, School of Anatomical Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); Des Moines University, Department of Anatomy, Des Moines, USA (GRID:grid.255049.f) (ISNI:0000 0001 2110 718X) 
 University of the Witwatersrand, School of Anatomical Sciences, Johannesburg, South Africa (GRID:grid.11951.3d) (ISNI:0000 0004 1937 1135); University of Cape Town, Division of Clinical Anatomy and Biological Anthropology, Department of Human Biology, Cape Town, South Africa (GRID:grid.7836.a) (ISNI:0000 0004 1937 1151) 
 Reykjavik University, Biomedical Engineering, Reykjavik, Iceland (GRID:grid.9580.4) (ISNI:0000 0004 0643 5232) 
 Copenhagen Zoo, Centre for Zoo and Wild Animal Health, Frederiksberg, Denmark (GRID:grid.480666.a) (ISNI:0000 0000 8722 5149) 
 King Saud University, KSU Mammals Research Chair, Department of Zoology, College of Science, Riyadh, Saudi Arabia (GRID:grid.56302.32) (ISNI:0000 0004 1773 5396) 
 King Saud University, KSU Mammals Research Chair, Department of Zoology, College of Science, Riyadh, Saudi Arabia (GRID:grid.56302.32) (ISNI:0000 0004 1773 5396); University of Pretoria, Department of Zoology and Entomology, Pretoria, South Africa (GRID:grid.49697.35) (ISNI:0000 0001 2107 2298) 
 Vanderbilt University, Department of Psychology, Department of Biological Sciences, Vanderbilt Brain Institute, Nashville, USA (GRID:grid.152326.1) (ISNI:0000 0001 2264 7217) 
10  Icahn School of Medicine at Mount Sinai, Nash Family Department of Neuroscience and Friedman Brain Institute, New York, USA (GRID:grid.59734.3c) (ISNI:0000 0001 0670 2351) 
11  Karolinska Institutet, Department of Neuroscience, Stockholm, Sweden (GRID:grid.4714.6) (ISNI:0000 0004 1937 0626) 
Publication year
2021
Publication date
2021
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2499224624
Copyright
© The Author(s) 2021. This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.