Although further research is needed to elucidate the possible link between AD, the ECS, and the metabolic, olfactory, or motor alterations, our results pointed out that alterations of the ECS components in the hypothalamus, olfactory cortex and cerebellum could appear in the early stages of disease progression in the APP/PS1 mice and could contribute to some of the behavioral alterations that are associated with AD (Zheng et al., 2018; Murphy, 2019; Wagner et al., 2019) but have been less studied. The gene discussed is APP; the disease is Alzheimer disease.