Identification of the Active EPA/AA-Binding Ether-Type Phosphatidylcholine Derived from the Starfish Patiria pectinifera for C2C12 Myotube Growth.

Concerns about nutritional approaches for promoting skeletal muscle mass and function have increased. This study assessed the effects of starfish-derived glycerophospholipids (PLs) (SPL), characterized by unique ether-linked subclasses, alkylacyl (Alk)- and alkenylacyl (Pls)-PL, on skeletal muscle function, focusing on myotube formation in C2C12 myoblasts. SPL was prepared via chloroform/methanol extraction from Patiria pectinifera, followed by silica gel chromatography fractionation. Myoblasts were induced to differentiate with or without SPL treatment. On day 7 of differentiation, 50 μg/mL of SPL treatment increased myotube diameter. The phosphatidylcholine (PC) fraction (SPC) also enhanced myotube growth at 30 μg/mL. LC-MS/MS analysis indicated the most abundant PC molecular species in SPC were Alk- and Pls-PC with eicosapentaenoic acid and arachidonic acid. Treatment with 1-O-hexadecyl-2-arachidonoyl-PC, 1-1(Z)-hexadecenyl-2-arachidonoyl-PC or 1-O-hexadecyl-2-eicosapentaenoyl-PC increased myotube diameter and myokine Il-15 mRNA expression. These results demonstrate a novel functionality of SPC and highlight the role of ether-type PC molecules in muscle function.