Noninvasive Quantification of Human Brain Antioxidant Concentrations Via Double Edited 1H MRS Throughout Intravenous Delivery of Vitamin C

Melissa Terpstra¹, Carolyn Torkelson¹, Susan Raatz¹, Tonya White¹, Kamil Ugurbil¹, Ivan Tkac¹

Antioxidant defenses are involved in protecting against dementia and neurodegenerative disease. Vitamin C (ascorbate) and glutathione (GSH) are the two most concentrated chemical antioxidants in the CNS. Ascorbate (Asc) and GSH were double edited with MEGA-PRESS at 4 T in the human occipital lobe throughout 24 hours following IV administration of vitamin C. Measured data are not consistent with an Asc concentration ([Asc]) change larger than 8 % (95 % CI) at any time point. Ability to overrule changes greater than 8% enables studies on antioxidant defenses. [Asc] may have increased at the 10 hour time point in one subject.