Task Activation Results in Regional 13C-Lactate Signal Increase in the Human Brain

Uthayakumar, B.; Cappelletto, N. I. C.; Bragagnolo, N. D.; Chen, A. P.; Ma, N.; Perks, W. J.; Endre, R.; Tam, F.; Graham, S. J.; Heyn, C.; Keshari, K. R.; Soliman, H.; Cunningham, C. H.

doi:10.1101/2024.02.01.577808

bioRxiv · 10.1101/2024.02.01.577808

Task Activation Results in Regional 13C-Lactate Signal Increase in the Human Brain

Uthayakumar, B.·Cappelletto, N. I. C.·Bragagnolo, N. D.·Chen, A. P.·Ma, N.·Perks, W. J.·Endre, R.·Tam, F.·Graham, S. J.·Heyn, C.·Keshari, K. R.·Soliman, H.·Cunningham, C. H.

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Abstract

Hyperpolarized-13C magnetic resonance imaging (HP-13C MRI) was used to image changes in 13C-lactate signal during a visual stimulus condition in comparison to an eyes-closed control condition. Whole-brain 13C-pyruvate, 13C-lactate and 13C-bicarbonate production was imaged in healthy volunteers (N=6, ages 24-33) for the two conditions using two separate hyperpolarized 13C-pyruvate injections. BOLD-fMRI scans were used to delineate regions of functional activation. 13C-metabolite signal was normalized by 13C-metabolite signal from the brainstem and the percentage change in 13C-metabolite signal conditions was calculated. A one-way Wilcoxon signed-rank test showed a significant increase in 13C-lactate in regions of activation when compared to the remainder of the brain (p = 0.02, V = 21). No significant increase was observed in 13C-pyruvate (p = 0.11, V = 17) or 13C-bicarbonate (p = 0.95, V = 3) signal. The results show an increase in 13C-lactate production in the activated region that is measurable with HP-13C MRI.

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Uthayakumar, B., Cappelletto, N. I. C., Bragagnolo, N. D., Chen, A. P., Ma, N., Perks, W. J., Endre, R., Tam, F., Graham, S. J., Heyn, C., Keshari, K. R., Soliman, H., Cunningham, C. H.. 2024-02-01. Task Activation Results in Regional 13C-Lactate Signal Increase in the Human Brain. https://doi.org/10.1101/2024.02.01.577808

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