EFFECT OF ALGA EXTRACTS CONTAINING CAROTENOIDS ON AGE-RELATED COGNITIVE DECLINE

Brain aging is characterized by a slow and progressive alteration of cognitive functions which can lead to neurodegenerative diseases. Nutrition appears as a major strategy to prevent and reduce aged-related cognitive decline. In that respect, marine by-products may represent an important source of novel biologically active substances for the development of nutritional supplementations. In this study, we first investigated the intrinsic biological properties of carotenoids contained in alga extracts, on microglia-neuron (BV2-N2a) co-culture after LPS induction. Our results demonstrated that diadinoxanthin and violaxanthin have anti-inflammatory, antioxidant properties and the capacity to modulate apoptotic factors in BV2-N2a cells co-culture. Then, C57Bl/6J aged mice were supplemented with alga extracts containing carotenoids for 13 weeks and were submitted to behavioral tests to assess their mood and memory. Diadinoxanthin was present in the Phaeophyceae extract (extract A) and violaxanthin in the Nannochloropsis extract (extract B). Our findings showed that supplementation with a mix of alga A and B extracts prevented short term spatial memory alterations induced by aging and improved contextual fear memory. Supplementation with B extracts alone tended to improve short term spatial memory. These results demonstrated a synergic effect of diadinoxanthin and violaxanthin obtained from alga. Thus, alga extracts containing diadinoxanthin and violaxanthin may represent an innovative strategy to prevent age-related cognitive decline.