N-acetyl-cysteine (NAC): an amino acid with powerful neuroprotective and anti-oxidant actions, even down at the mitochondrial level. NAC is a precursor of glutathione, one of the most powerful endogenous immune enhancers. NAC and glutathione can also fight brain inflammation as well as free radicals.

NAC has been shown to chelate heavy metals, such as lead and mercury, lightening their toxic load on the brain. NAC can lower brain damaging homocysteine levels. Some studies suggest that combining NAC with other anti-oxidants and the B vitamins significantly reduces the risk for serious memory loss later in life. In fact, NAC has been shown to improve cognitive function in a group with elevated homocysteine, an acknowledged brain toxin.

References:

Susan A. Farr, H. Fai Poon, Dilek Dogrukol-Ak, Jeniffer Drake, William A. Banks, Edward Eyerman,D. Allan Butterfield‡ and John E. Morley.The antioxidants α-lipoic acid and N-acetylcysteine reverse memory impairment and brain oxidative stress in aged SAMP8 mice. Journal of Neurochemistry 2003; 84(5);1173

M. Zafarullah A, W. Q. Li A, J. Sylvester A, M. Ahmad A. Molecular mechanisms of N-acetylcysteine actions. Cellular and Molecular Life Sciences (CMLS) 2003;60(1); 6-20.

Mushfiquddin Khan, Bipanjeet Sekhon, Manu Jatana, Shailendra Giri, Anne G. Gilg, Charanpal Sekhon, Inderjit Singh, Avtar K. Singh. Administration of N-acetylcysteine after focal cerebral ischemia protects brain and reduces inflammation in a rat model of experimental stroke.

Sekhon B, Sekhon C, Khan M, Patel SJ, Singh I, Singh AK.N-Acetyl cysteine protects against injury in a rat model of focal cerebral ischemia. Brain Res. 2003 May 2;971(1):1-8.

Lizard G, Miguet C, Bessede G, Monier S, Gueldry S, Neel D, Gambert P. Impairment with various antioxidants of the loss of mitochondrial transmembrane potential and of the cytosolic release of cytochrome c occuring during 7-ketocholesterol-induced apoptosis. Free Radic Biol Med. 2000 Mar 1;28(5):743-53.

Banaclocha MM.Therapeutic potential of N-acetylcysteine in age-related mitochondrial neurodegenerative diseases. Med Hypotheses. 2001 Apr;56(4):472-7.