title: Plasma vitamin C concentrations in patients with cystic fibrosis: evidence of associations with lung inflammation.
abstract: Vitamin C status and possible associations with the disease process in cystic fibrosis (CF) patients were investigated. Plasma vitamin C concentrations in patients from two different mid-European populations (Swiss, n = 62; Austrian, n = 60) taking no or low-dose vitamin C from multivitamin supplements did not differ from each other or from control subjects (n = 34). Vitamin C concentrations decreased with age (5.05 mumol.L-1, y-1). When followed up for 12 mo, patients had the highest plasma vitamin C concentrations in February and the lowest in May and August (P < 0.01); the decrease in vitamin C was accompanied by increases in plasma malondialdehyde (P < 0.001) and tumor necrosis factor alpha concentrations (P < 0.01). During supplementation with vitamin E for 2 mo or beta-carotene for 12 mo vitamin C concentrations did not change. They correlated inversely with white blood cell count (r = -0.36, P = 0.008), bands (r = -0.36, P = 0.02), alpha 1-acid glycoprotein (r = -0.45, P = 0.002), interleukin 6 (r = -0.46, P = 0.0006), and neutrophil elastase/alpha 1-proteinase inhibitor complexes (r = -0.34, P = 0.02). In patients with vitamin C concentrations < 40 mumol/L, all indexes of inflammation were relatively high, whereas those with concentrations > 80 mumol/L (upper quartile of control subjects) showed clearly lower values. These results are consistent with the hypothesis that by scavenging oxygen free radicals vitamin C interacts with an inflammation-amplifying cycle of activation of alveolar macrophages and neutrophils, release of proinflammatory cytokines and oxygen free radicals, and inactivation of antiproteases.
authors.affiliation: Department of Pediatrics, University of Zurich, Switzerland.
authors.forename: B M
authors.initials: BM
authors.lastname: Winklhofer-Roob
authors.forename: H
authors.initials: H
authors.lastname: Ellemunter
authors.forename: M
authors.initials: M
authors.lastname: Frühwirth
authors.forename: S E
authors.initials: SE
authors.lastname: Schlegel-Haueter
authors.forename: G
authors.initials: G
authors.lastname: Khoschsorur
authors.forename: M A
authors.initials: MA
authors.lastname: van't Hof
authors.forename: D H
authors.initials: DH
authors.lastname: Shmerling
mesh_terms: D000293:Adolescent; D000328:Adult; D001205:Ascorbic Acid / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003550:Cystic Fibrosis / Q000097:blood* / Q000209:etiology / Q000503:physiopathology; D016207:Cytokines / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D007223:Infant; D007249:Inflammation / Q000097:blood / Q000209:etiology / Q000503:physiopathology; D015850:Interleukin-6 / Q000097:blood; D019272:Leukocyte Elastase / Q000097:blood; D015227:Lipid Peroxidation / Q000502:physiology; D008171:Lung Diseases / Q000097:blood* / Q000209:etiology / Q000503:physiopathology; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D009752:Nutritional Status; D009961:Orosomucoid / Q000032:analysis / Q000378:metabolism; D012621:Seasons; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000378:metabolism; D014810:Vitamin E / Q000008:administration & dosage / Q000494:pharmacology; D019207:beta Carotene / Q000008:administration & dosage / Q000097:blood / Q000494:pharmacology
chemical_list: D016207:Cytokines; D015850:Interleukin-6; D009961:Orosomucoid; D014409:Tumor Necrosis Factor-alpha; D019207:beta Carotene; D014810:Vitamin E; D008315:Malondialdehyde; D019272:Leukocyte Elastase; D001205:Ascorbic Acid