Some updates regarding the regulation of [brain] PUFA metabolism: Supelco AOCS Research Award lecture

Docosahexaenoic acid (DHA; 22:6n-3) is prevalent in the brain, playing a crucial role in regulating cell survival, neurogenesis, and neuroinflammation. While DHA can be obtained through dietary sources, particularly fish, it can also be synthesized from alpha-linolenic acid (ALA; 18:3n-3), a plant-based precursor, via a series of desaturation and elongation reactions in the liver. The efficiency of DHA synthesis from ALA remains a topic of considerable debate, particularly important in light of ecological concerns regarding fish stocks and an increase in non-fish-eating populations. Compounding this issue is a limited understanding of human DHA requirements. In this presentation, I will discuss new isotopic methods that have revealed several unexpected insights into DHA metabolism, including a feedback inhibition mechanism whereby DHA suppresses its own synthesis in the liver.   I will also provide updates on the role of different carriers of DHA and their transport to the brain.  These and other findings will be contextualized within the framework of DHA requirements and the regulation of brain DHA levels.