In vitro uptake of labeled amino acids by red blood cells of children with protein-calorie malnutrition

Changes in the plasma amino acid profile in anorexia nervosa

We evaluated and measured by high performance liquid chromatography the plasma amino acid levels in 11 female patients with anorexia nervosa during a period of significant loss of body weight, compared with 11 healthy age-matched controls. Total amino acid and total branched-chain amino acid levels were similar in both groups, however significantly higher levels of glycine and ornithine were found in anorexia nervosa patients, as well as significantly lower levels of leucine, tyrosine and lysine compared with controls. The glycine/valine and phenylalanine/tyrosine ratios were significantly higher in anorexia nervosa patients than in control subjects. The levels and ratios of other amino acids were within the normal range, with no significant differences between the two groups. Changes in the plasma amino acid profile in anorexia nervosa patients can be explained by chronic severe malnutrition and prolonged stress.

Plasma and erythrocyte amino acid concentrations in anorexia nervosa

Plasma and erythrocyte amino acid concentrations in seven female patients in the acute stage of anorexia nervosa were compared with values in the same subjects after refeeding, and with normal controls. We also compared these values with literature values from patients with protein-calorie malnutrition and prolonged starvation in an attempt to identify a biological indicator of severity and prognosis. Our data indicate: (1) Routine laboratory analyses that reflect protein status do not differentiate normal subjects from patients with anorexia nervosa. (2) The plasma aminogram in the acute stage of anorexia nervosa differs from normal, and differs from values reported for both protein malnutrition and prolonged starvation. (3) The Whitehead ratio clearly separates the acutely ill anorectic state from the treated state and from normal controls. (4) Both erythrocyte and plasma amino acid concentrations differ from normal in anorexia nervosa, but changes in erythrocyte concentrations are more obvious. (5) Erythrocyte glycine concentrations are unique, in that values were persistently elevated at all stages of illness in anorexia nervosa. (6) Erythrocyte-to-plasma amino acid ratios do not provide a biological index of severity and prognosis for patients with anorexia nervosa, in contrast to data reported for individuals with protein malnutrition.

Protein-calorie malnutrition: a study of red blood cell and serum enzymes during and after crisis

This paper reports a study of changes in red blood cell enzymes and some serum parameters during and after treatment of protein-calorie malnutrition. The red cell GSH levels were low during the crisis, together with the levels of GSSG:NADPH reductase, GSH:H2O2 peroxidase, aspartate aminotransferase and alanine aminotransferase. After treatment the levels of all these enzymes increased significantly to normal values. Of the serum parameters investigated, significant reduction in the activity of the enzymes cholinesterase, catecholamine oxidase, total proteins, albumin, urea and electrolytes were obvious, and returned to normal values after treatment. Ceruloplasmin activity remained low even after three weeks' treatment and could not be related to copper levels. The results are discussed in relation to anemia and liver damage that may accompany the syndrome.

Hormone-fuel concentrations in anephric subjects. Effect of hemodialysis (with special reference to amino acids)

Arterial blood concentrations of insulin, glucagon, and various substrates were determined in six anephric subjects in the postabsorptive state and immediately after hemodialysis. Plasma glucose and serum insulin concentrations were normal, and declined during dialysis. Plasma glucagon was elevated and remained unchanged. There was moderate hypertriglyceridemia before dialysis, but this decreased significantly after administration of heparin just before the start of dialysis, and at the end of dialysis was lowered further into the normal range. Comparison of postabsorptive whole blood concentrations of amino acids with those in normal, healthy adults revealed striking differences. Glutamine, proline, citrulline, glycine and both 1- and 3-methyl-histidines were increased, while serine, glutamate, tyrosine, lysine, and branched-chain amino acids were decreased. The glycine/serine ratio was elevated to 300% and tyrosine/phenylalanine ratio was lowered to 60% of normal. To investigate the potential role of blood cells in amino acid transport, the distribution of individual amino acids in plasma and blood cell compartments was studied. Despite a markedly diminished blood cell mass (mean hematocrit, 20.6 +/- 1.4%), there was no significant decrease in the fraction of most amino acids present in the cell compartment, and this was explained by increases of several amino acids in cellular water. None were decreased. Furthermore, during dialysis, whole blood and plasma amino acids declined by approximately 30% and 40%, respectively, whereas no significant change was observed in the cell compartment. Alanine was the only amino acid whose concentration declined in the cells as well as in plasma. The results indicate (a) significant alterations in the concentrations of hormones and substrates in patients on chronic, intermittent hemodialysis; (b) removal of amino acids during hemodialysis, predominantly from the plasma compartment, with no significant change in cell content; and (c) a redistribution of amino acids in plasma and blood cell compartments with increased gradients of most of the amino acids per unit cell water, by mechanism(s) as yet undetermined.