title: Effects of vitamin C and E supplementation on endogenous antioxidant systems and heat shock proteins in response to endurance training.
abstract: Reactive oxygen and nitrogen species are important signal molecules for adaptations to training. Due to the antioxidant properties of vitamin C and E, supplementation has been shown to blunt adaptations to endurance training. In this study, we investigated the effects of vitamin C and E supplementation and endurance training on adaptations in endogenous antioxidants and heat shock proteins (HSP). Thirty seven males and females were randomly assigned to receive Vitamin C and E (C + E; C: 1000 mg, E: 235 mg daily) or placebo (PLA), and underwent endurance training for 11 weeks. After 5 weeks, a subgroup conducted a high intensity interval session to investigate acute stress responses. Muscle and blood samples were obtained to investigate changes in proteins and mRNA related to the antioxidant and HSP system. The acute response to the interval session revealed no effects of C + E supplementation on NFκB activation. However, higher stress responses to exercise in C + E group was indicated by larger translocation of HSPs and a more pronounced gene expression compared to PLA. Eleven weeks of endurance training decreased muscle GPx1, HSP27 and αB-crystallin, while mnSOD, HSP70 and GSH remained unchanged, with no influence of supplementation. Plasma GSH increased in both groups, while uric acid decreased in the C + E group only. Our results showed that C + E did not affect long-term training adaptations in the antioxidant- and HSP systems. However, the greater stress responses to exercise in the C + E group might indicate that long-term adaptations occurs through different mechanisms in the two groups.
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Kristoffer T
authors.initials: KT
authors.lastname: Cumming
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Truls
authors.initials: T
authors.lastname: Raastad
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Geir
authors.initials: G
authors.lastname: Holden
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway.
authors.forename: Nasser E
authors.initials: NE
authors.lastname: Bastani
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Damaris
authors.initials: D
authors.lastname: Schneeberger
authors.affiliation: Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy.
authors.forename: Maria Paola
authors.initials: MP
authors.lastname: Paronetto
authors.affiliation: Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy.
authors.forename: Neri
authors.initials: N
authors.lastname: Mercatelli
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Hege N
authors.initials: HN
authors.lastname: Ostgaard
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway.
authors.forename: Ingrid
authors.initials: I
authors.lastname: Ugelstad
authors.affiliation: Department of Movement, Human and Health Sciences, University of Rome "Foro Italico", Rome, Italy.
authors.forename: Daniela
authors.initials: D
authors.lastname: Caporossi
authors.affiliation: Department of Nutrition, Institute of Basic Medical Sciences, University of Oslo, Oslo, Norway Division of Cancer Medicine, Surgery and Transplantation, Oslo University Hospital, Oslo, Norway.
authors.forename: Rune
authors.initials: R
authors.lastname: Blomhoff
authors.affiliation: Department of Physical Performance, Norwegian School of Sport Sciences, Oslo, Norway Norwegian Olympic Sports Center, Oslo, Norway.
authors.forename: Gøran
authors.initials: G
authors.lastname: Paulsen
keywords: Antioxidant enzymes; NFκB; gene expression; stress proteins