Correlation of Amine Concentrations in Blood and Cerebrospinal Fluid in Healthy Volunteers and Migraineurs

Many central nervous system disorders (CNS), including chronic pain and migraine, involve metabolic changes in the brain. These changes are best detected and monitored in cerebrospinal fluid (CSF), which requires lumbar puncture. Blood-based measurements may offer an alternative, if they reflect CSF changes. To assess this, we measured and correlated the concentrations of 39 amino acids, biogenic amines, and other amines in blood and CSF of 95 healthy volunteers and, in addition, correlated the ratios of 741 amines. Amines were measured using a validated UPLC-MS platform. In healthy volunteers, only 4/39 (10.3%) analyzed amine metabolite concentrations had a correlation coefficient ≥ 0.70. Correlations of metabolite ratios were significantly better for 308/741 (41.5%) combinations. Specifically, ratios of amino acids showed high correlations. In addition, amines were investigated in 197 participants with migraine. Six amine metabolite ratios were different in migraineurs versus healthy volunteers. Most blood amine concentrations do not reflect those in CSF, but many of the ratios did correlate between CSF and plasma, showing diagnostic potential. This study improves our understanding of blood-CSF relationships, and our data suggest that ratios of amines may be of relevance to CNS disorders, as we showed for migraine.