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bioRxiv · 10.1101/2023.01.13.523957

Evidence of Lactate Shuttling in the Human Brain using Hyperpolarized 13C-MRI

Uthayakumar, B.·Soliman, H.·Chen, A. P.·Bragagnolo, N. D.·Endre, R.·Perks, W. J.·Ma, N.·Heyn, C.·Cunningham, C. H.
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Abstract

PurposeTo test the hypothesis that lactate shuttling contributes to the 13C-lactate and 13C-bicarbonate signal observed in the awake human brain using hyperpolarized 13C MRI. MethodsHealthy human volunteers (n = 6) were scanned twice using hyperpolarized 13C-MRI, with reduced radiofrequency saturation of 13C-lactate on one set of scans. 13C-lactate, 13C-bicarbonate, and 13C-pyruvate signals for 132 brain regions across each set of scans were compared using a clustered Wilcoxon sum rank test. ResultsReduced 13C-lactate radiofrequency saturation resulted in a significantly greater 13C-bicarbonate signal (p = 0.04). These changes were observed across the majority of brain regions. ConclusionRadiofrequency saturation of 13C-lactate leads to a decrease in 13C-bicarbonate signal, demonstrating that the 13C-lactate generated from the injected 13C-pyruvate is being converted back to 13C-pyruvate and oxidized throughout the human brain.

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Uthayakumar, B., Soliman, H., Chen, A. P., Bragagnolo, N. D., Endre, R., Perks, W. J., Ma, N., Heyn, C., Cunningham, C. H.. 2023-01-16. Evidence of Lactate Shuttling in the Human Brain using Hyperpolarized 13C-MRI. https://doi.org/10.1101/2023.01.13.523957

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