SORL1 and Alzheimer disease: Two reports demonstrated increased lactate-to-pyruvate ratios in animal models of multiple sclerosis, likely stemming from the large lactate production of proliferating immune cells.26,27 As multiple sclerosis, contrary to Alzheimer’s disease, primarily an inflammatory disease, their results and the data presented here suggest that Alzheimer’s disease–disposing SORL1 mutations and neuroinflammation lead to opposite changes in the pyruvate-to-lactate exchange.