SCD and X-linked adrenoleukodystrophy: While LXR activation is indeed a driver of SCD1 expression, the endogenous LXR agonist 25-hydroxcholesterol is also reported to reduce saturated VLCFAs in X-ALD fibroblasts and oligodendrocytes by decreasing the expression of VLCFA elongase 1 (ELOVL1) [29].