title: NOS2 polymorphisms associated with the susceptibility to pulmonary arterial hypertension with systemic sclerosis: contribution to the transcriptional activity.
abstract: Systemic sclerosis (SSc) is a connective tissue disease characterized by tissue fibrosis. One of several complications of SSc, pulmonary arterial hypertension (PAH) can be refractory to treatment, both novel and established. In the present study we investigated the ratio of circulating nitric oxide to endothelin-1 in patients with both SSc and PAH, and determined whether polymorphisms in NOS2 (the nitric oxide synthase 2 gene) are associated with susceptibility to PAH. Endothelin-1 in plasma and nitric oxide metabolites (nitrate and nitrite) in serum were measured. The nitric oxide/endothelin-1 ratio was significantly lower in patients with both SSc and PAH than in patients with SSc only or in healthy control individuals. We confirmed the presence of two single nucleotide polymorphisms at positions -1,026 and -277 and a pentanucleotide repeat (CCTTT) at -2.5 kilobases. There were significant differences in single nucleotide polymorphisms between patients with SSc who had PAH and those who did not, and between patients with both SSc and PAH and healthy control individuals. The CCTTT repeat was significantly shorter in patients with both SSc and PAH than in patients with SSc only or in healthy control individuals. Transcriptional activity were analyzed using the luciferase reporter assay. The transcriptional activity of NOS2 was much greater in fibroblasts transfected by a vector with a long allele of the CCTTT repeat than in those transfected by a vector with a short allele. Polymorphisms in the NOS2 gene are associated with transcriptional activity of the NOS2 gene and with susceptibility to SSc-related PAH.
authors.affiliation: Institute of Rheumatology, Tokyo Women's Medical University, Tokyo, Japan. y-kawa@ior.twmu.ac.jp
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kawaguchi
authors.forename: Akiko
authors.initials: A
authors.lastname: Tochimoto
authors.forename: Masako
authors.initials: M
authors.lastname: Hara
authors.forename: Manabu
authors.initials: M
authors.lastname: Kawamoto
authors.forename: Tomoko
authors.initials: T
authors.lastname: Sugiura
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Katsumata
authors.forename: Jun
authors.initials: J
authors.lastname: Okada
authors.forename: Hirobumi
authors.initials: H
authors.lastname: Kondo
authors.forename: Mitsuo
authors.initials: M
authors.lastname: Okubo
authors.forename: Naoyuki
authors.initials: N
authors.lastname: Kamatani
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019332:Endothelin-1 / Q000097:blood; D005260:Female; D020022:Genetic Predisposition to Disease; D006239:Haplotypes; D006801:Humans; D006976:Hypertension, Pulmonary / Q000209:etiology* / Q000235:genetics; D008297:Male; D008875:Middle Aged; D009569:Nitric Oxide / Q000097:blood; D052247:Nitric Oxide Synthase Type II / Q000235:genetics*; D009994:Osmolar Concentration; D011110:Polymorphism, Genetic; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D012595:Scleroderma, Systemic / Q000097:blood / Q000150:complications* / Q000235:genetics*; D020080:Tandem Repeat Sequences; D014158:Transcription, Genetic
chemical_list: D019332:Endothelin-1; D009569:Nitric Oxide; D052247:Nitric Oxide Synthase Type II