Gangliosides are glycosphingolipids present in mammalian cell membranes, playing important structural and functional roles. Human studies on the health benefits of gangliosides are increasing, but knowledge gaps regarding ganglioside analysis exist. The study aimed to investigate blood sample type (serum/plasma), storage conditions, diurnal, day-to-day variation and acute effects of consuming bovine-derived gangliosides on circulating monosialylated gangliosides. Seventy-one women (18-40 yrs, 20-≤30.0 kg/m2) were enrolled and 61 completed the intervention. They visited the clinic three times following overnight fasting. Serum/plasma gangliosides were analyzed over 2 h (visit-1), 8 h (visit-2) and 8 h following either zero or high ganglioside meals (visit-3). Samples stored at -20 °C and -70 °C were analyzed at 3-, 6-, 12- and 18-months. Plasma and serum GM3-gangliosides did not differ, plasma GM3 did not change diurnally, from day-to-day, in response to a high vs. low ganglioside meal or after 7-days low ganglioside vs. habitual diet (P > 0.05). GM3 concentrations were lower in samples stored at -70 °C vs. -20 °C from 6-months onwards and decreased over time with lowest levels at 12- and 18-months stored at -70 °C. In conclusion, either serum/plasma stored at -20- or -70 °C for up to 6 months, are acceptable for GM3-ganglioside analysis. Blood samples can be collected at any time of the day and participants do not have to be in the fasted state.
Keywords: acute; day-to-day variation; diurnal variation; gangliosides; plasma; postprandial; serum; storage temperature; storage time; women of child bearing age.