Premium
Effects of 13 weeks of aerobic training on basal gene expression
Author(s) -
Luden Nicholas,
Jemiolo Bozena,
Whitsett David,
Trappe Scott
Publication year - 2007
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.21.6.a1303-d
Subject(s) - myogenin , myod , medicine , gene expression , endocrinology , citrate synthase , myosin , biology , basal (medicine) , skeletal muscle , pyruvate kinase , gene , glycolysis , myogenesis , biochemistry , enzyme , metabolism , insulin
The altered gene expression that contributes to changes in muscle protein concentration plays an integral role in training adaptations. Accordingly, the aim of this investigation was to determine basal expression of select genes in skeletal muscle before and after 13 weeks of run training. The genes of interest included: Proteolytic : Atrogin‐1, muscle RING finger 1 (MuRF‐1), Myogenic : myogenin, myogenic differentiation factor (MyoD), Cytokines : interleukin 6 (IL‐6), IL‐15, tumor necrosis factor (TNF)‐α, and Metabolic : pyruvate dehydrogenase kinase‐4 (PDK‐4), and hexokinase II (HK II). Four males and 3 females (22 ± 1 yr, 68 ± 2 kg) performed 13 weeks of progressive run training. The lateral gastrocnemius was biopsied before and after training. Gene expression was analyzed by real‐time RT PCR, normalized to GAPDH, and compared to pre‐training values. Run training increased basal gene expression of myogenin (1.6‐fold), MyoD (1.5‐fold), IL‐15 (1.9‐fold), TNF‐α (2.8‐fold), PDK‐4 (3.8‐fold), and HK‐II (2.8‐fold). Training had no effect on proteolytic gene expression. It is likely that the myogenic, metabolic, and IL‐15 response reflects an accumulation of these transcripts in the adapted muscle in an ongoing effort to become more oxidative. This theory is supported by the findings previously reported by our laboratory (JAP 101: –727, 2006) that there was an increase in both myosin heavy chain (MHC)‐I composition (8%) and citrate synthase activity (37%) in these same subjects.