Anxiolytic-like effects of Lupinus angustifolious protein hydrolysates in alzheimer model mice

Alzheimer's disease (AD), which is characterized by a devastating and progressive loss of memory, is the principal neurodegenerative disease in the elderly population worldwide. As a consequence, AD patients present neuropsychiatric symptoms, such as anxiety, causing sleeping difficulty, irritability, agitation, or aggressiveness. Previous studies have demonstrated that a high-fat diet, in addition to exacerbating AD, aggravates anxiety. We have demonstrated that Lupinus angustifolius protein hydrolysates (LPHs) have anti-inflammatory and antioxidant effects, key factors for AD and anxiety. Thus, this study aimed to evaluate the potential effects of LPHs on spatial memory and anxiety of a preclinical model of AD. ApoE−/− mice fed with a western diet were intragastrically treated with LPHs (or a vehicle) for 14 weeks. Spatial memory and anxiety were then assessed through the Morris water maze and elevated plus maze, respectively. The results did not show significant differences in spatial memory between groups. However, a significant increase (p < 0.05) in time in open arms, center time, the number of crossings, and a reduction of anxiety behavior were observed in LPH-treated mice. This is the first study showing that an LPH treatment causes anxiolytic effects, pointing to LPHs as a potential component of future nutritional therapies.