Altered amino acid homeostasis in subjects affected by fibromyalgia.
Department of Internal Medicine, Division of Rheumatology, University of Pisa, Via Roma 67, 56126 Pisa, Italy.
OBJECTIVES: To evaluate plasma amino acids (AA) concentrations in patients affected by fibromyalgia (FM) and to study the relationships between their levels and FM clinical parameters. DESIGN AND METHODS: 20 AA were assessed in 34 FM patients and in 18 healthy volunteers by means of a modified version of the Waters picotag method. RESULTS: Significant lower plasma taurine, alanine, tyrosine (Tyr), valine, methionine, phenylalanine, threonine concentrations and sum of essential AAs were observed in FM patients vs healthy controls (P<0.05). Tyr CAAs ratio and the sum of AAs competing with tryptophan for brain uptake resulted significantly reduced in FM (p<0.05). Significant correlation were found between FM clinical parameters and certain AAs. CONCLUSIONS: Our results suggest a probable defects of gut malabsorption of certain AAs in FM patients. Moreover, given the reduced Tyr CAAs ratio in FM patients, a possible impairment of cathecolaminergic system in the FM syndrome may be suggested.
PMID: 19281806 [PubMed - as supplied by publisher]