RESUMEN
INTRODUCTION: It has been claimed that continuous and high production of nitric oxide (NO) and its metabolites may be involved in the pathogenesis of several neurological disorders such as multiple sclerosis. A number of studies have demonstrated that lithium regulates NO levels in disorders of the central nervous system. The aim of this study was to investigate whether NO as a marker of disease activity is correlated with lithium deficiency in relapsing remitting multiple sclerosis (RR-MS). METHODS: This case-controlled study comprised 44 patients with RR-MS and 43 healthy subjects matched by age, gender, smoking status, and body mass index. The Griess reaction was used to measure the NO metabolites, nitrite and nitrate in serum. In addition serum lithium levels were measured using atomic absorption spectrometry method. The mean serum NO concentrations in the groups RR-MS and the control were 18.5 ± 3.1µM and 15.5 ± 2.9µM, respectively. Data analysis showed a statistically significant difference between subjects with RR-MS and the control group (p < 0.05). Furthermore, serum lithium concentrations in RR-MS (0.57 ± 0.2) were remarkably lower in RR-MS patients than the controls (2.29 ± 0.7) (p < 0.05). CONCLUSION: The present findings suggest that lithium deficiency may upregulates NO production in RR-MS. Further studies with larger samples are needed to confirm the effects of lithium treatment on NO pathway and its association with synaptic plasticity in RR-MS patients.
