Dietary Isomers of Sialyllactose Increase Ganglioside Sialic Acid Concentrations in the Corpus Callosum and Cerebellum of Formula‐fed Piglets (LB320)

Abstract

Sialic acid (SA) is a key component of human milk oligosaccharides and neural tissues. SA accumulates in the brain rapidly during neonatal development and is thought to play an important role in brain development . This study aimed to determine if different isomers of sialyllactose (SL) enrich brain SA of developing neonatal piglets. Day‐old pigs were randomized among 6 diets (control, 2g/L 3’‐SL, 4g/L 3’‐SL, 2g/L 6’‐SL, or 4g/L 6’‐SL, or 2g/L polydextrose + 2g/L galacto‐oligosaccharide; n=9) and fed three times per day for 21 d. Pigs were euthanized and the left hemisphere of the brain was dissected into cerebrum, cerebellum, corpus callosum, and hippocampus regions. Total and lipid‐bound (ganglioside) SA were assayed following extraction with chloroform:methanol (2:1), and free SA was calculated by difference. Protein‐bound SA was measured in the insoluble residue following suspension in PBS containing 1% Triton X‐100. SA was determined using a modified periodic acid‐resorcinol reaction. Dietary SL did not affect feed intake, growth or fecal consistency. Ganglioside‐bound SA in the corpus callosum of pigs fed 2g/L of 3’‐SL (359±16 μg SA/g wet tissue) or 6’‐SL (361±16 μg SA/g) was increased by 15% over control pigs (314±16 μg SA/g; P<0.05). Similarly, ganglioside‐bound SA in the cerebellum of pigs fed 4g/L of 3’‐SL (416±14 μg SA/g) was increased by 10% over control pigs (377±14 μg SA/g; P < 0.05). In conclusion, supplementation of formula with 3’‐ or 6’‐SL can enrich ganglioside SA in the brain of suckling piglets.Grant Funding Source: Mead Johnson Nutrition