title: Increased intrathecal nitric oxide formation in multiple sclerosis; cerebrospinal fluid nitrite as activity marker.
abstract: Nitric oxide is formed from L-arginine by a family of enzymes: nitric oxide synthase (NOS). The inducible nitric oxide synthase is activated by cytokines and it has been suggested that activation of the enzyme gives rise to neurotoxic levels of reactive nitrogen oxides. This enzyme has been shown to be localized in multiple sclerosis (MS) lesions but the role of nitric oxide formation in the pathogenesis of MS is still unclear. Using capillary electrophoresis, we have analysed nitrite and nitrate in cerebrospinal fluid (CSF) and demonstrate increased levels of reactive nitrogen products in 17 patients with MS. The total levels of oxidized nitrogen products were significantly elevated in MS patients when compared with controls. In patients with active MS, nitrite levels were significantly increased when compared with controls and patients in remission. This is supportive of NOS induction in MS. We suggest that capillary electrophoresis analysis of nitrite and nitrate in CSF could provide a clinically useful way to determine disease activity in MS.
authors.affiliation: Department of Clinical Neuroscience at the Department of Molecular Medicine, Karolinska Hospital, Karolinska Institutet, Stockholm, Sweden.
authors.forename: L
authors.initials: L
authors.lastname: Brundin
authors.forename: E
authors.initials: E
authors.lastname: Morcos
authors.forename: T
authors.initials: T
authors.lastname: Olsson
authors.forename: N P
authors.initials: NP
authors.lastname: Wiklund
authors.forename: M
authors.initials: M
authors.lastname: Andersson
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers; D018450:Disease Progression; D019075:Electrophoresis, Capillary; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009103:Multiple Sclerosis / Q000134:cerebrospinal fluid*; D009569:Nitric Oxide / Q000134:cerebrospinal fluid*; D019001:Nitric Oxide Synthase / Q000134:cerebrospinal fluid; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000134:cerebrospinal fluid*
chemical_list: D015415:Biomarkers; D009573:Nitrites; D009569:Nitric Oxide; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II