1H-NMR Analysis of Amino Acid Metabolism in Cerebrospinal Fluid of Dogs with Neurological Distemper

Canine Distemper Virus (CDV) infection causes a multifocal demyelinating progressive disease within the central nervous system (CNS) that results in wide range of neurological symptoms. Pathological changes in the brain or CNS could be observed by analyzing cerebrospinal fluid (CSF). Therefore, this study aimed to investigate the concentrations of amino acids in the CSF of dogs with neurological form of CDV infection, and to identify amino acids as markers that can be used in the diagnosis, pathogenesis, and treatment of the disease. Heathy dogs (n=6), confirmed by clinical and laboratory examinations (Healthy group), and CDV-infected dogs (n=10) with neurological symptoms, confirmed by clinical, laboratory, and rapid diagnostic test kits (Distemper group), were used. CSF samples were obtained with an appropriate method and were subjected to 1H-NMR analysis. Identification was made on 10, whereas quantification on 8 amino acids. L-tyrosine, L-phenylalanine, L-threonine, and L-alanine concentrations were significantly lower, while L-histidine and L-tryptophan were significantly higher than the Healthy group (p<0.05). It was concluded that L-tyrosine could be used for assessing mental status changes, L-phenylalanine for evaluating neuroprotective responses, L-threonine and L-histidine for gauging the extent of neurodegeneration and ventricular degeneration, L-alanine for exploring cellular stress and energy metabolism, and L-tryptophan for understanding the process of sympathetic nervous system activation.