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bioRxiv · 10.1101/2024.05.14.594105

Glycolytic metabolism modulation on spinal neuroinflammation and vital functions following cervical spinal cord injury

Abstract

High spinal cord injuries (SCIs) often result in persistent diaphragm paralysis and respiratory dysfunction. Chronic neuroinflammation within the damaged spinal cord after injury plays a prominent role in limiting functional recovery by impeding neuroplasticity. In this study, we aimed to reduce glucose metabolism that supports neuroinflammatory processes in an acute preclinical model of C2 spinal cord lateral hemisection in rats. We administered 2-deoxy-D-glucose (2-DG; 200 mg/kg/day s.c., for 7 days) and evaluated the effect on respiratory function and chondroitin sulfate proteoglycans (CSPGs) production around spinal phrenic motoneurons. Contrary to our initial hypothesis, our 2-DG treatment did not have any effect on diaphragm activity and CSPGs production in injured rats, although slight increases in tidal volume were observed. Unexpectedly, it led to deleterious effects in uninjured (sham) animals, characterized by increased ventilation and CSPGs production. Ultimately, our results seem to indicate that this 2-DG treatment paradigm may create a neuroinflammatory state in healthy animals, without affecting the already established spinal inflammation in injured rats. Given the beneficial effects of 2-DG observed in other studies on neuronal activity and inflammation, adjusting 2-DG doses and/or increasing treatment duration should be explored to reduce deleterious inflammatory processes occurring after SCI.

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BibTeXRIS

Michel-Flutot, P., Mansart, A., Vinit, S.. 2024-05-17. Glycolytic metabolism modulation on spinal neuroinflammation and vital functions following cervical spinal cord injury. https://doi.org/10.1101/2024.05.14.594105

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