Effect of intermittent hypoxic training on HIF gene expression in human skeletal muscle and leukocytes.
Intermittent hypoxic exposure with exercise training is based on the assumption that brief exposure to hypoxia is sufficient to induce beneficial muscular adaptations mediated via hypoxia-inducible transcription factors (HIF). We previously demonstrated (Mounier et al. Med Sci Sports Exerc 38:1410-1417, 2006) that leukocytes respond to hypoxia with a marked inter-individual variability in HIF-1alpha mRNA. This study compared the effects of 3 weeks of intermittent hypoxic training on hif gene expression in both skeletal muscle and leukocytes. Male endurance athletes (n = 19) were divided into an Intermittent Hypoxic Exposure group (IHE) and a Normoxic Training group (NT) with each group following a similar 3-week exercise training program. After training, the amount of HIF-1alpha mRNA in muscle decreased only in IHE group (-24.7%, P < 0.05) whereas it remained unchanged in leukocytes in both groups. The levels of vEGF(121) and vEGF(165) mRNA in skeletal muscle increased significantly after training only in the NT group (+82.5%, P < 0.05 for vEGF(121); +41.2%, P < 0.05 for vEGF(165)). In leukocytes, only the IHE group showed a significant change in vEGF(165) (-28.2%, P < 0.05). The significant decrease in HIF-1alpha mRNA in skeletal muscle after hypoxic training suggests that transcriptional and post-transcriptional regulations of the hif-1alpha gene are different in muscle and leukocytes.
Mounier
Rémi
R
Faculté de Médecine, Laboratoire de Physiologie-Biologie du Sport, 28 place Henri Dunant, 63000 Clermont-Ferrand, France. remimounier@voila.fr
Pialoux
Vincent
V
Roels
Belle
B
Thomas
Claire
C
Millet
Grégoire
G
Mercier
Jacques
J
Coudert
Jean
J
Fellmann
Nicole
N
Clottes
Eric
E
D000328:Adult; D015870:Gene Expression; D006801:Humans; D000860:Hypoxia / Q000235:genetics* / Q000378:metabolism*; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000235:genetics*; D007962:Leukocytes / Q000378:metabolism*; D008297:Male; D027501:Monocarboxylic Acid Transporters / Q000235:genetics / Q000378:metabolism; D009124:Muscle Proteins / Q000235:genetics / Q000378:metabolism; D018482:Muscle, Skeletal / Q000378:metabolism*; D010101:Oxygen Consumption / Q000235:genetics; D012333:RNA, Messenger / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000235:genetics / Q000378:metabolism
C497442:HIF1A protein, human; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D027501:Monocarboxylic Acid Transporters; D009124:Muscle Proteins; D012333:RNA, Messenger; C406962:SLC16A4 protein, human; D042461:Vascular Endothelial Growth Factor A