Aims: The main aim of this study was to verify the effect of natalizumab on the
levels of circulating catecholamines and indolamine and their possible relation with MS.
Methods: For this purpose, 12 healthy individuals (control group) and 12 relapsing-remitting
multiple sclerosis patients (RR-MS) were selected. The patients were treated with 300 mg of
natalizumab during 56 weeks (1 dose/4 weeks) (MS-56). This selection was based on the
McDonalds revision criterion and scheduled to star treatment with natalizumab. Blood samples
were taken before treatment (basal level) and after 56 weeks of using natalizumab.
Melatonin was measured in serum and in plasma, catecholamines (dopamine, epinephrine,
and norepinephrine), carbonylated proteins, 8-hydroxy-2’deoxyguanosine (8OH-dG) and the
ratio reduced glutathione/oxidised glutathione (GSH/GSSG).
Results: The epinephrine and dopamine levels diminished in the basal group with respect to
the control and did not recover normal levels with the treatment. The melatonin was decreased in RR-MS patients
and went back to its normal levels with natalizumab. Norepinephrine was increased in RR-MS and decreased in
MS-56 until it equalled the control group.
Conclusion: Natalizumab normalizes altered melatonin and norepinephrine levels in MS.