Docosahexaenoic Acid (DHA): An Ancient Nutrient for the Modern Human Brain

Abstract

Modern humans have evolved with a staple source of preformed docosahexaenoic acid (DHA) in the diet. An important turning point in human evolution was the discovery of high-quality, easily digested nutrients from coastal seafood and inland freshwater sources. Multi-generational exploitation of seafood by shore-based dwellers coincided with the rapid expansion of grey matter in the cerebral cortex, which characterizes the modern human brain. The DHA molecule has unique structural properties that appear to provide optimal conditions for a wide range of cell membrane functions. This has particular implications for grey matter, which is membrane-rich tissue. An important metabolic role for DHA has recently been identified as the precursor for resolvins and protectins. The rudimentary source of DHA is marine algae; therefore it is found concentrated in fish and marine oils. Unlike the photosynthetic cells in algae and higher plants, mammalian cells lack the specific enzymes required for the de novo synthesis of alpha-linolenic acid (ALA), the precursor for all omega-3 fatty acid syntheses. Endogenous synthesis of DHA from ALA in humans is much lower and more limited than previously assumed. The excessive consumption of omega-6 fatty acids in the modern Western diet further displaces DHA from membrane phospholipids. An emerging body of research is exploring a unique role for DHA in neurodevelopment and the prevention of neuropsychiatric and neurodegenerative disorders. DHA is increasingly being added back into the food supply as fish oil or algal oil supplementation.

Identification of prostamides, fatty acyl ethanolamines, and their biosynthetic precursors in rabbit cornea

“…The function of other FA-EA species is under investigation and effects on sleeping pattern, appetite control, and depression have been published to date (51)(52)(53). EP-EA was not detected in the cornea, which was unsurprising as eicosapentaenoic acid is a enzymes possess no sequence homology and are optimally active under basic and acidic conditions respectively, as also refl ected in their intracellular localization with FAAH found in membrane fractions and N-AAA in lysosomes minor species and DHA is the predominant omega-3 fatty acid found in the brain and ocular tissues ( 41,54 ).…”

Docosahexaenoic acid: one molecule diverse functions

“…Docosahexaenoic acid (DHA, C22:6, x-3) is an ancient nutrient for the modern human brain [1]. Isotope dating studies, relating diet to the evolution of the large human brain, led to a hypothesis that the evolution of the modern human brain with expanded cortex coincided with the inclusion of seafood in the diet [2,3] of our ancestor dwellers.…”

Diet Induced Modifications of Fatty-Acid Composition in Mealworm Larvae (Tenebrio molitor)

“…PUFAs influence cellular membrane fluidity, functions, signaling and expression (Jump, 2002). They play essential roles in brain functioning (Bradbury, 2011;Uauy, Hoffman, Peirano, Birch, & Birch, 2001), whole body metabolism (Arnold, Giroud, Valencak, & Ruf, 2015;Geiser & Kenagy, 1987;Hulbert, 2010;McGuire, Fenton, & Guglielmo, 2013;Munro & Thomas, 2004), muscular performance (Valencak, Arnold, Tataruch, & Ruf, 2003), immunity (Stanley & Miller, 2006;Stanley-Samuelson et al, 1991;Ziboh, Miller, & Cho, 2000) and reproduction (Fair, Doyle, Diskin, Hennessy, & Kenny, 2014;Rahman, Gasparini, Turchini, & Evans, 2014;Safarinejad, Hosseini, Dadkhah, & Asgari, 2010;Strzeżek, Fraser, Kuklińska, Dziekońska, & Lecewicz, 2004;Zalata, Christophe, Depuydt, Schoonjans, & Comhaire, 1998). Animal species use a combination of desaturases and elongases to convert alpha-linolenic acid (ALA, 18:3ω-3) and linoleic acid (LA,) into longer polyunsaturated chains.…”