Taken together these observations suggest that peroxisomal dysfunction (loss of Abcd1) in oligodendrocytes predisposes them to an apoptotic response in X-ALD and that SAHA treatment protects against VLCFA-mediated proapoptotic signaling pathways and loss of Abcd1-deficient B12 oligodendrocytes. Here, ABCD1 is linked to X-linked adrenoleukodystrophy.