ConclusionBAs are derived from cholesterol, and at least 17 enzymesare involved in the synthesis of various bile acids from cholesterol (Russell 2003). Mutations in nine of these enzymesresult in various pathologies including neurological defects,suggesting that BAs play a critical role in the brain (Heubiet al. 2007). ~ 90 years ago, it was found that sodium taurocholate, a bile salt, caused demyelination (Weil 1930), andit was hypothesized that this bile salt might facilitate demyelination by entering the brain from the circulation, furthersuggesting that BAs play a critical role in the brain