Acute C-peptide, insulin and branched chain amino acid response to feeding in formula and breast fed infants.
The response of C-peptide in serum and urine and of glucose and branched chain amino acids in blood to formula and breast feeding was assessed in six breast-fed and six formula-fed infants 3-6 months of age. We analysed serum C-peptide, branched chain amino acids (BCAA) in blood, and blood glucose in the fasting state at 90' and 180' after a regular meal. The excretion of urinary C-peptide and creatinine was also determined. The formula-fed infants received a formula in current use, containing 15-16 g protein/l and with a casein/whey ratio of 40/60. In the fasting state, no significant inter-group difference was found in the level of serum C-peptide or the valine/glycine ratio. Postprandially, the formula-fed infants had significantly higher serum C-peptide values and valine/glycine ratio than the breast-fed infants, p less than 0.05. No significant inter-group difference was found for blood glucose. The urinary C-peptide/creatinine ratio was significantly lower in the breast-fed group, p = 0.02, and significantly correlated both to the valine/glycine ratio at 90', rs = 0.75, p = 0.02 and to the serum C-peptide value at 90', rs = 0.66, p = 0.03. These results confirm that in formula-fed infants the insulin response to a meal is enhanced compared to that in breast-fed infants. The finding of similar blood glucose values in the two groups may also indicate an insulin resistance in the formula-fed infants following a meal.
Wallensteen
M
M
Department of Pediatrics, Karolinska Institute, St. Göran's Children's Hospital, Stockholm, Sweden.
Lindblad
B S
BS
Zetterström
R
R
Persson
B
B
D000597:Amino Acids, Branched-Chain / Q000097:blood*; D001786:Blood Glucose / Q000032:analysis*; D001942:Breast Feeding; D002096:C-Peptide / Q000097:blood* / Q000652:urine; D003404:Creatinine / Q000652:urine; D005260:Female; D005998:Glycine / Q000097:blood; D006801:Humans; D007223:Infant; D007225:Infant Food; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007532:Isoleucine / Q000097:blood; D007930:Leucine / Q000097:blood; D008297:Male; D008895:Milk, Human / Q000378:metabolism*; D014633:Valine / Q000097:blood
D000597:Amino Acids, Branched-Chain; D001786:Blood Glucose; D002096:C-Peptide; D007328:Insulin; D007532:Isoleucine; D003404:Creatinine; D007930:Leucine; D014633:Valine; D005998:Glycine