Transport of docosahexaenoic acid across the blood–brain barrier is decreased in aged mice

Nutrients are actively taken up by the brain through various transporters at the blood–brain barrier (BBB). In the aged brain, central nervous system (CNS) disorders can result from a lack of nutrients, including decreased levels of docosahexaenoic acid (DHA), which is important for many neurophysiological functions and is associated with memory and cognitive dysfunction. To compensate for decreased brain DHA, orally supplied DHA must be transported from circulating blood to the brain across the BBB via its transporter, the major facilitator superfamily domain-containing protein 2a (Mfsd2a). Although BBB integrity is known to be altered in aging, the influence of aging on DHA transport across the BBB it is not well understood.