A1 Journal article (refereed)
The relationship between mitochondrial respiration, resting metabolic rate and blood cell count in great tits (2024)

Thoral, E., García-Díaz, C. C., Persson, E., Chamkha, I., Elmér, E., Ruuskanen, S., & Nord, A. (2024). The relationship between mitochondrial respiration, resting metabolic rate and blood cell count in great tits. Biology Open, 13(3). https://doi.org/10.1242/bio.060302

JYU authors or editors

Publication details

All authors or editors: Thoral, Elisa; García-Díaz, Carmen C.; Persson, Elin; Chamkha, Imen; Elmér, Eskil; Ruuskanen, Suvi; Nord, Andreas

Journal or series: Biology Open

eISSN: 2046-6390

Publication year: 2024

Publication date: 22/02/2024

Volume: 13

Issue number: 3

Publisher: The Company of Biologists

Publication country: United Kingdom

Publication language: English

DOI: https://doi.org/10.1242/bio.060302

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/94222

Abstract

Although mitochondrial respiration is believed to explain a substantial part of the variation in resting metabolic rate (RMR), few studies have empirically studied the relationship between organismal and cellular metabolism. We therefore investigated the relationship between RMR and mitochondrial respiration of permeabilized blood cells in wild great tits (Parus major L.). We also studied the correlation between mitochondrial respiration traits and blood cell count, as normalizing mitochondrial respiration by the cell count is a method commonly used to study blood metabolism. In contrast to previous studies, our results show that there was no relationship between RMR and mitochondrial respiration in intact blood cells (i.e., with the ROUTINE respiration). However, when cells were permeabilised and interrelation re-assessed under saturating substrate availability, we found that RMR was positively related to phosphorylating respiration rates through complexes I and II (i.e., OXPHOS respiration) and to the mitochondrial efficiency to produce energy (i.e., Net phosphorylating efficiency), though variation explained by the models was low (i.e., linear model: R2=0.14 to 0.21). However, unlike studies in mammals, LEAK respiration without (i.e., L(n)) and with (i.e., L(Omy)) adenylates was not significantly related to RMR. These results suggest that phosphorylating respiration in blood cells can potentially be used to predict RMR in wild birds, but that this relationship may have to be addressed in standardized conditions (permeabilized cells) and that the prediction risks being imprecise. We also showed that, in our conditions, there was no relationship between any mitochondrial respiration trait and blood cell count. Hence, we caution against normalising respiration rates using this parameter as is sometimes done. Future work should address the functional explanations for the observed relationships, and determine why these appear labile across space, time, taxon, and physiological state.

Keywords: metabolism; cell physiology; cell respiration; mitochondria; great tit

Free keywords: erythrocyte; oxidative metabolism; resting metabolic rate; basal metabolic rate; great tit; mitochondria

Contributing organizations

Ministry reporting: Yes

Preliminary JUFO rating: 1