Abstract
Background: Clinical studies of the associations of vitamin E with lung function have reported conflicting results. However, these reports primarily examine the α-tocopherol isoform of vitamin E and have not included the isoform γ-tocopherol which we recently demonstrated in vitro opposes the function of α-tocopherol. We previously demonstrated, in vitro and in animal studies, that the vitamin E isoform α-tocopherol protects, but the isoform γ-tocopherol promotes lung inflammation and airway hyperresponsiveness.Methods: To translate these findings to humans, we conducted analysis of 4526 adults in the Coronary Artery Risk Development in Young Adults (CARDIA) multi-center cohort with available spirometry and tocopherol data in blacks and whites. Spirometry was obtained at years 0, 5, 10, and 20 and serum tocopherol was from years 0, 7 and 15 of CARDIA.Results: In cross-sectional regression analysis at year 0, higher γ-tocopherol associated with lower FEV1 (p = 0.03 in blacks and p = 0.01 in all participants) and FVC (p = 0.01 in blacks, p = 0.05 in whites, and p = 0.005 in all participants), whereas higher α-tocopherol associated with higher FVC (p = 0.04 in blacks and whites and p = 0.01 in all participants). In the lowest quartile of α-tocopherol, higher γ-tocopherol associated with a lower FEV1 (p = 0.05 in blacks and p = 0.02 in all participants). In contrast, in the lowest quartile of γ-tocopherol, higher α-tocopherol associated with a higher FEV1 (p = 0.03) in blacks. Serum γ-tocopherol >10 μM was associated with a 175-545 ml lower FEV1 and FVC at ages 21-55 years.Conclusion: Increasing serum concentrations of γ-tocopherol were associated with lower FEV1 or FVC, whereas increasing serum concentrations of α-tocopherol was associated with higher FEV1 or FVC. Based on the prevalence of serum γ-tocopherol >10 μM in adults in CARDIA and the adult U.S. population in the 2011 census, we expect that the lower FEV1 and FVC at these concentrations of serum γ-tocopherol occur in up to 4.5 million adults in the population.
| Original language | English (US) |
|---|---|
| Article number | 31 |
| Journal | Respiratory research |
| Volume | 15 |
| Issue number | 1 |
| DOIs | |
| State | Published - Mar 15 2014 |
Bibliographical note
Funding Information:This study was supported by National Institutes of Health Grant R-1 AT004837 (J.M.C-M). The Coronary Artery Risk Development in Young Adults (CARDIA) Study is conducted and supported by the National Heart, Lung, and Blood Institute (NHLBI) in collaboration with the CARDIA Study Investigators. CARDIA is supported by contracts HHSN268201300025C, HHSN268201300026C, HHSN268201300027C, HHSN268201300028C, HHSN268201300029C, and HHSN268200900041C from the National Heart, Lung, and Blood Institute and the Intramural Research Program of the National Institute on Aging. Tocopherol measurements were supported by a grant for the YALTA study R01-HL-53560. The spirometry reading center at Year 20 was at Latter Day Saints Hospital, Salt Lake City, Utah subcontract to CARDIA Coordinating Center PF-HC95095.
Keywords
- FEV1
- FVC
- Human
- α-tocopherol
- γ-tocopherol