ABCB1 and amyotrophic lateral sclerosis: Drug brain uptake is further restricted due to Abcb1 upregulation in brain capillary endothelial cells and in astrocytes of mice with a SOD1 mutation, a commonly used animal ALS model (Jablonski et al., 2012; Qosa et al., 2016b; Chan et al., 2017).