NPC1 and obesity due to melanocortin 4 receptor deficiency: The eventual permeability of lysosomes and the release of cathepsins to the cytosol could lead to mitochondrial damage and promote lysosome dysfunction and cellular death in these tissues, where the overall evidence is not yet conclusive and more studies are needed to clarify how dysregulated cathepsins mediate lysosome defects in obesity, NPC, and Gaucher diseases.