Methods for quantifying n-acetylcysteine and glutathione in brain tissue using magnetic resonance spectroscopy

A method for optimizing a dosing regimen of N-acetylcysteine for treatment of a brain disorder, comprising:

• administering a dose of N-acetylcysteine to a subject having the brain disorder;
• performing magnetic resonance spectroscopy on brain tissue of the subject to acquire spectral data comprising a cysteine β-proton resonance signal and an N-acetyl proton resonance signal;
• separately quantifying a concentration of N-acetylcysteine and a concentration of glutathione in the brain tissue based on the spectral data, wherein the concentration of N-acetylcysteine is determined based on the N-acetyl proton resonance signal and the concentration of glutathione is determined based on a comparison of the cysteine β-proton resonance signal and the N-acetyl proton resonance signal;
• and
• adjusting at least one of a dosage amount or a dosing interval of N-acetylcysteine based on the separately quantified concentrations of N-acetylcysteine and glutathione.

A system for quantifying N-acetylcysteine and glutathione in brain tissue, comprising:

• a magnetic resonance imaging device configured to perform magnetic resonance spectroscopy on a region of brain tissue of a subject who has been administered N-acetylcysteine;
• and
• a processor configured to:
• receive magnetic resonance spectroscopy data from the magnetic resonance imaging device, the magnetic resonance spectroscopy data comprising a cysteine β-proton signal and an N-acetyl proton signal from the region of brain tissue;
• determine a concentration of N-acetylcysteine in the region of brain tissue based on the N-acetyl proton signal;
• and
• determine a concentration of glutathione in the region of brain tissue based on a subtraction of a contribution of N-acetylcysteine from the cysteine β-proton signal.