Lithium ameliorates Niemann-Pick C1 disease phenotypes by impeding STING/SREBP2 activation

Niemann-Pick disease type C (NP-C) is a genetic lysosomal disorder associated with progressive neurodegenerative phenotypes. Its therapeutic options are very limited. Here, we show that lithium treatment improves ataxia and feeding phenotypes, attenuates cerebellar inflammation and degeneration, and extends survival in Npc1 mouse models. In addition, lithium suppresses STING activation, SREBP2 processing to its mature form and the expression of the target genes in the Npc1 mice and in Npc1-deficient fibroblasts. Lithium impedes STING/SREBP2 transport from the ER to the Golgi, a step required for STING activation and SREBP2 processing, probably by lowering cytosolic calcium concentrations. This effect of lithium on STING/SREBP2 transport provides a mechanistic explanation for lithium's effects on Npc1 mice. Thus, this study reveals a potential therapeutic option for NP-C patients as well as a strategy to reduce active STING/SREBP2 pathway.