Marine Plasmalogens: A Gift from the Sea with Benefits for Age-Associated Diseases

Abstract

Aging increases oxidative and inflammatory stress caused by a reduction in metabolism and clearance, thus leading to the development of age-associated diseases. The quality of our daily diet and exercise is important for the prevention of these diseases. Marine resources contain various valuable nutrients, and unique glycerophospholipid plasmalogens are found abundantly in some marine invertebrates, including ascidians. One of the major classes, the ethanolamine class (PlsEtn), exists in a high ratio to phospholipids in the brain and blood, while decreased levels have been reported in patients with age-associated diseases, including Alzheimer’s disease. Animal studies have shown that the administration of marine PlsEtn prepared from marine invertebrates improved PlsEtn levels in the body and alleviated inflammation. Animal and human studies have reported that marine PlsEtn ameliorates cognitive impairment. In this review, we highlight the biological significance, relationships with age-associated diseases, food functions, and healthcare materials of plasmalogens based on recent knowledge and discuss the contribution of marine plasmalogens to health maintenance in aging.

Marine Animal Co-Products—How Improving Their Use as Rich Sources of Health-Promoting Lipids Can Foster Sustainability

“…Plasmalogens were first proposed to be endogenous antioxidants and to be involved in membrane bilayer formation [217]. Lately, they have also been proposed to have a beneficial impact on atherosclerosis, on the prevention of inflammation (neuroinflammation in particular), on the improvement of cognitive function, and on the inhibition of neuronal cell death [217][218][219]. In fact, oral ingestion or plasmalogen replacement therapy were both put forward as novel strategies to target neurodegenerative diseases (namely Alzheimer's disease) [217] and chronic inflammatory disorders [220].…”

“…In the specific case of plasmalogens, they have also garnered interest from a pharmacological perspective, having been proposed to display attractive functionalities as healthcare materials. In fact, they have been proposed to present promising characteristics to serve as constituents of functional membranes of biosensors, light-activated liposomes, or nanoparticles with endosomal escape capabilities [219]. Moreover, marine organisms have also been proposed as alternative sources of complex lipids (as plasmalogens) as an alternative to more common sources, such as bovine brains, whose use is now unwarranted due to past outbreaks of bovine spongiform encephalopathy [219].…”

Simultaneous Intake of Chlorella and Ascidian Ethanolamine Plasmalogen Accelerates Activation of BDNF–TrkB–CREB Signaling in Rats

“…The leading theory on the cause of AD is the amyloid hypothesis [ 5 ], in which amyloid-β, a component protein of amyloid plaques, accumulates in the brain and causes neuronal degeneration; however, this hypothesis has not been fully elucidated. Plasmalogen concentrations decrease with atrophy in the brains of patients with AD [ 6 , 7 ]. The brain is rich in lipids in comparison with other organs.…”

“…The brain is rich in lipids in comparison with other organs. The human brain contains approximately 65% lipids by dry weight, and its lipid composition is highly specific; for example, plasmalogen, which accounts for only approximately 5% of phosphatidylethanolamine in the liver, accounts for 50–65% of phosphatidylethanolamine in the brain [ 6 , 7 , 8 ]. Plasmalogen is involved in membrane fusion during synaptic transmission in the nervous system due to its propensity for hexagonal phase formation [ 9 ].…”

“…In Japan, ascidians ( Halocynthia roretzi ), a protochordate species, are mainly cultivated for food in the Miyagi and Hokkaido prefectures. Ascidians have particularly high levels of ethanolamine plasmalogen (PlsEtn) with docosahexaenoic acid (DHA) in their chemical structure, which is found in abundance in the human brain [ 7 , 14 ]. We previously reported in vitro and in vivo studies in which ascidian PlsEtn suppressed neuroblast apoptosis [ 15 ], inhibited amyloid-β aggregation [ 16 ], and improved cognitive function [ 17 ].…”