AKT1 and Huntington disease: The most thoroughly characterised survival pathway in HD is the protein kinase B (AKT) pathway; enhanced activation of AKT in models of HD has been attributed to the reduced expression of its inhibitor, PH domain leucine-rich repeat protein phosphatase 1 (PHLPP1), which is suppressed in HdhQ111, R6/1, R6/2 and HD94 striata, as well as in human putamen [14].