This form of B-12 is very nuroprotective. methylcobalamin

I get mine 5 mg from www.lef.org and "eat them" all day long.

jackD

Eur J Pharmacol. 1993 Sep 7;241(1):1-6.

Protective effects of a vitamin B12 analog, methylcobalamin, against glutamate cytotoxicity in cultured cortical neurons.

Akaike A, Tamura Y, Sato Y, Yokota T.
SourceDepartment of Neuropharmacology, Faculty of Pharmacy and Pharmaceutical Sciences, ***uyama University, Japan.

Abstract
The effects of methylcobalamin, a vitamin B12 analog, on glutamate-induced neurotoxicity were examined using cultured rat cortical neurons. Cell viability was markedly reduced by a brief exposure to glutamate followed by incubation with glutamate-free medium for 1 h. Glutamate cytotoxicity was prevented when the cultures were maintained in methylcobalamin-containing medium.

Glutamate cytotoxicity was also prevented by chronic exposure to S-adenosylmethionine, which is formed in the metabolic pathway of methylcobalamin.

Chronic exposure to methylcobalamin and S-adenosylmethionine also inhibited the cytotoxicity induced by N-methyl-D-aspartate or sodium nitroprusside that releases nitric oxide. In cultures maintained in a standard medium, glutamate cytotoxicity was not affected by adding methylcobalamin to the glutamate-containing medium. In contrast, acute exposure to MK-801, a NMDA receptor antagonist, prevented glutamate cytotoxicity.

These results indicate that chronic exposure to methylcobalamin protects cortical neurons against NMDA receptor-mediated glutamate cytotoxicity.

PMID: 7901032 [PubMed - indexed for MEDLINE]