Plasma catecholamine metabolite levels and the activities of psychiatric symptoms in systemic lupus erythematosus

Abstract

Neuropsychiatric systemic lupus erythematosus (NPSLE) is accompanied by neurological or psychiatric symptoms that can be severe. We hypothesized plasma 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) levels were the biological marker that reflected the severity of the NPSLE psychiatric symptoms, and we examined MHPG and HVA levels in systemic lupus erythematosus (SLE) patients. The participants were 42 healthy volunteers and 41 SLE patients. SLE patients were divided into the three groups: NPSLE with psychiatric symptoms (NP group), NPSLE without psychiatric symptoms (NN group), and SLE without neuropsychiatric symptoms (S group). All blood samples were drawn before (T0) and after 4 weeks of treatment (T4) in all SLE patients, and once in the healthy volunteers. Plasma levels of MHPG and HVA were analyzed using high-performance liquid chromatography. Plasma MHPG levels at T0 were significantly increased in the SLE compared to those in healthy volunteers. The NN group had the greatest increase compared with other SLE patient groups. There were no significant differences in plasma HVA levels at T0 between the four groups, and there was also no difference in MHPG and HVA plasma levels between T0 and T4. Hyperactivity of noradrenergic neurons and/or sympathetic nerves might be involved in SLE pathophysiology.