NPC1 Mutation Treatment Protocols

We used two different therapeutic schedules for the NPC1^−/− mutants and their NPC1^+/+ controls. The first one was a combination treatment (COMBI) of synergistically working drugs utilizing HPβCD, allopregnanolone and miglustat, starting at postnatal day P7 with an injection of allopregnanolone (Pregnan-3α-ol-20-one; 25 mg/kg; Sigma Aldrich, St. Louis, MO, USA) dissolved in cyclodextrin (2-hydroxypropyl-β-cyclodextrin; 4000 mg/kg, i.p.; Sigma Aldrich, in Ringer’s solution) once a week, as described by [34 (link)]. Additionally, 300 mg/kg miglustat (N-butyl-deoxynojirimycin; generous gift of Actelion Pharmaceuticals, Allschwil, Schwitzerland) dissolved in normal saline solution was intraperitoneally injected daily from P10 to P22. Afterwards, miglustat powder was administered mixed with food (summarized in Figure 10). For the second treatment schedule, allopregnanolone and miglustat were omitted and only HPβCD was injected weekly. Controls included treated and untreated NPC1^+/+ animals as well as untreated NPC1^−/− mutants.