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bioRxiv · 10.1101/2021.06.03.446848

An exploration of metabolic and transcriptional responses in mouse skeletal muscles responding to acute sedentary hypoxia

Xue, F.·Huang, G.·Wang, X.·Deng, J.·Pang, L.·Gan, Z.
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Abstract

Skeletal muscles are involved in responses to acute hypoxia as the largest organ in the body. However, as a hypoxic-tolerant tissue, responses in skeletal muscles caused by acute sedentary hypoxia are much less studied. We measured metabolites in skeletal muscles from mice exposed to 8% O2 for 0 minute, 15 minutes and 2 hours and studied the potential relationship between metabolite levels and mRNA levels by reconstructing genome-based metabolic networks and meta-analyzing differentially expressed genes acquired in skeletal muscles after 2 hours of 8% O2 exposure. The metabolite measurement indicated a significant increase in glutamine metabolism but not lactate metabolism in mouse skeletal muscles after 2 hours of hypoxia, where the metabolic responses as a whole were moderate. The central-dogma based metabolic flux analysis suggested an involvement of glutamine metabolism, though, as a whole, metabolite changes and gene changes didnt show a high correlation. Among metaoblites, glutamine metabolism indicated a significant response and a consistent change which could be interpreted by genome-based network analysis. In summary, though this study suggested a moderate metabolic response which has a weak correlation with gene expression change as a whole, glutamine metabolism indicated rapid responses in skeletal muscles responding to acute sedentary hypoxia.

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Xue, F., Huang, G., Wang, X., Deng, J., Pang, L., Gan, Z.. 2021-06-03. An exploration of metabolic and transcriptional responses in mouse skeletal muscles responding to acute sedentary hypoxia. https://doi.org/10.1101/2021.06.03.446848

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