Plasma tryptophan levels and anorexia in liver cirrhosis.

Objective: Increased brain tryptophan (TRP) availability for serotonin synthesis may play a role in the pathogenesis of anorexia. Since in chronic liver failure, increased plasma and cerebrospinal fluid TRP concentrations are characteristically reported, we hypothesize that also in liver cirrhosis increased brain TRP availability may constitute the pathogenic mechanism of anorexia. To test this hypothesis, the association between anorexia and plasma TRP was investigated.

Plasma amino acid imbalance in patients with lung and breast cancer.

In order to evaluate whether different solid tumors may specifically influence plasma free amino acid (PFAA) profile, PFAA were analysed in seventy-four patients with lung (41 patients) and breast cancer (33 patients) and 28 healthy subjects. In lung cancer patients a significant reduction of gluconeogenic amino acids, threonine, serine, glycine and a significant increase of free tryptophan and glutamic acid was found. In breast cancer patients a significant increase of ornithine, glutamic acid and free tryptophan was found.