Effect of neonatal undernutrition on rat brain gangliosides.

Effects of age and neonatal undernutrition were studied on total and fractions of gangliosides (GT1, GD1b, GD1a and GM1) in rat brain. GT1, GD1b + GD1a and GM1 are being presented here as polysialo-, disialo-, and monosialo-gangliosides. Undernutrition was induced by feeding mothers a low protein diet during lactation. The concentration of gangliosides increased to its maximum level by the age of 3 weeks and then decreased to its adult value by the age of 8 weeks. Polysialo gangliosides (GT1) comprised the maximum amount of gangliosides at birth (40%) and decreased to an adult value by 3 weeks of age. Disialo ganglioside GD1b increased to its maximum by 2 weeks and then leveled off. Disialo ganglioside GD1a and GM1 showed a decrease by 2 weeks and then reached to its adult value by 4 weeks. Neonatal undernutrition results in a decreased body and brain weight at all ages studied (7, 14 and 21 days) as well as total ganglioside concentration by 36%, 15% and 55% respectively at 7, 14 and 21 days. Polysialo gangliosides (GT1) constitute the major fraction of gangliosides at 21 days in undernourished rats as compared to controls, whereas mono- and di-sialo gangliosides remained decreased at all three ages compared to controls. This indicates the possibility of an underlying metabolic defect in undernourished animals.