Trial reportInhalation toxicology2009
Combination treatment with high-dose vitamin C and alpha-tocopherol does not enhance respiratory-tract lining fluid vitamin C levels in asthmatics.
Trial report in Inhalation toxicology, 2009. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers, 2 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
12 citing papers in PubMed, 2 syntheses or guidelines pooled it, 26 citations in OpenAlex.
- Vitamins C and E for asthma and exercise-induced bronchoconstriction.The Cochrane database of systematic reviews · 2014Pooled it
- Vitamin C for asthma and exercise-induced bronchoconstriction.The Cochrane database of systematic reviews · 2013Pooled it
- The Role of Vitamins in the Pathogenesis of Asthma.International journal of molecular sciences · 2023Review
- Asthma, allergy and vitamin E: Current and future perspectives.Free radical biology & medicine · 2022Article
- Amelioration of PMRespiratory research · 2019Article
- Identification of vitamin C transporters in the human airways: a cross-sectional in vivo study.BMJ open · 2015Article
- Supplementation with γ-tocopherol attenuates endotoxin-induced airway neutrophil and mucous cell responses in rats.Free radical biology & medicine · 2014Article
- Vitamin E isoforms as modulators of lung inflammation.Nutrients · 2013Review
- Isoforms of Vitamin E Differentially Regulate PKCJournal of clinical & cellular immunology · 2013Article
- Effects of ex vivo γ-tocopherol on airway macrophage function in healthy and mild allergic asthmatics.Journal of innate immunity · 2013Article
- Mega-dose vitamin C attenuated lung inflammation in mouse asthma model.Anatomy & cell biology · 2010Article
- Isoforms of vitamin E differentially regulate inflammation.Endocrine, metabolic & immune disorders drug targets · 2010Review
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
8 authors at 2 institutions in 1 country.
Funding
Abstract
Oxidative stress plays a significant role in allergic airway inflammation. Supplementation with alpha-tocopherol (alone or combined with ascorbate/vitamin C) has been assessed as an intervention for allergic airway diseases with conflicting results. Enhancing levels of airway antioxidants with oral supplements has been suggested as an intervention to protect individuals from the effect of inhaled oxidants, although it is unclear whether supplementation changes tocopherol or vitamin C levels in both serum and airway fluids. Our objective was to obtain pilot safety and dosing data from 14 allergic asthmatic volunteers examining the effect of daily combination oral therapy with 500 mg alpha-tocopherol (alpha T) and 2 g vitamin C for 12 wk. We examined serum and airway fluid and cellular levels of alpha- and gamma-tocopherol (gamma T) and vitamin C to plan for future studies of these agents in asthma and allergic rhinitis. Six volunteers completed 12 wk of active treatment with alpha T and vitamin C and 8 completed placebo. Blood and sputum samples were obtained at baseline and at 6 wk and 12 wk of therapy and were analyzed for alpha T, gamma T, and vitamin C levels in the serum, sputum supernatant, and sputum cells. Combination treatment increased serum vitamin C and significantly decreased sputum alpha T and serum gamma T levels. No changes were found in sputum supernatant or sputum cell vitamin C or serum alpha T levels in the active treatment group. In conclusion, supplementation with alpha T and high-dose vitamin C does not augment vitamin C levels in the respiratory-tract lining fluid.
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What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.