ABSTRACT
In a study of the relationship of maternal nutrition to fetal development, the free amino acid concentration was determined in the plasma of 43 subjects sampled between the 20th to 30th (25 +/- 3.7) week of pregnancy. Significant positive correlations were found between mothers' 25-week plasma levels of aspartic acid, serine, alanine, tyrosine, ornithine, and arginine, and babies' size at birth. The concentration of total free amino acids in plasma from mothers of fetally malnourished infants, was significantly lower than that from mothers having normal babies. The branched chain amino acids isoleucine and valine were at normal levels, suggesting a sparing effect for these amino acids.
Subject(s)
Amino Acids/blood , Birth Weight , Placenta Diseases/blood , Female , Humans , Infant, Newborn , Pre-Eclampsia/blood , Pregnancy , Pregnancy Trimester, SecondABSTRACT
Plasma free amino acids were measured in six adult human subjects at four consecutive 1/2 hr intervals following meals containing either 50 g lactalbumin, 50 g heated lactalbumin, or no protein. After the lactalbumin meal, all essential and several nonessential amino acids increased in the plasma. After the heated lactalbumin meal, these increases were either much less or did not appear. Following the no protein meal all measured plasma amino acids fell. The absence of a response to the heated lactalbumin meal was considered to be related to a drop in digestibility of heated lactalbumin as measured in rats.
Subject(s)
Amino Acids/blood , Lactalbumin , Amino Acids, Essential/blood , Animals , Dietary Proteins/administration & dosage , Digestion , Female , Hot Temperature , Humans , Lactalbumin/metabolism , Male , Middle Aged , Proteins/metabolism , RatsABSTRACT
Fetal malnutrition has emerged as a significant health problem over the past decade. Present evidence suggests that maternal environment plays the major etiologic role in fetal malnutrition. The association of fetal malnutrition in mothers with chronic hypertension is well known, but fetal malnutrition is associated with maternal hypertension in less than 25 per cent of cases. Among a group of 182 pregnant women studied at midpregnancy for blood levels of vitamins, trace metals, proteins, amino acids, and parameters of maternal leukocyte energy metabolism, it was found that the concentration of 10 amino acids, alpha-1-globulin, zinc, and total carotenes had a statistically significant relationship to fetal growth. Similarly significant correlations were found for maternal leukocyte adenosine disphosphate, phosphofructokinase activity, ribonucleic acid (RNA) synthesis, and cell size. Maternal cigarette smoking was correlated with reduced fetal growth. Analysis showed that there was a significant reduction in leukocyte RNA synthesis and phosphokinase activity and in the plasma levels of 14 amino acids, and carotene in smoking mothers. This information lends support to the hypothesis that factors which affect the growth of fetal cells also will affect maternal leukocytes in a definable way.
