Phytoene and Phytoene-Rich Microalgae Extracts Extend Lifespan in C. elegans and Protect against Amyloid-β Toxicity in an Alzheimer’s Disease Model

Abstract

The role of foods is shifting from focusing on the provision of energy and basic nutrients to also include bioactive compounds that prevent the development of chronic age-related diseases. Mi-croalgae offer a source of nutritional compounds with important health effects, and have the po-tential for production of health-promoting products, without increasing agricultural land use and negatively impacting the environment. Here we investigate the health effects of microalgal ex-tracts with high levels of the colourless carotenoid phytoene. Phytoene is widely available from dietary sources and can be detected across different tissues in the human body. However, it is usually regarded as a precursor for the synthesis of other carotenoids, rather than a bioactive molecule. We utilised the model organism C. elegans to show that phytoene-rich extracts from Chlorella sorokiniana and Dunaliella bardawil have anti-ageing properties. The extracts protect against oxidative damage and amyloid-β42 proteotoxicity (a major pathology of Alzheimer's disease), and extends lifespan. We show that pure phytoene also has these anti-ageing effects, suggesting that phytoene is a bioactive molecule with positive effects on ageing and longevity.