Betaine supplementation enhances anabolic endocrine and Akt signaling in response to acute bouts of exercise

• Published in: European journal of applied physiology 2013-03, Vol.113 (3), p.793-802
• Main Authors: Apicella, Jenna M., Lee, Elaine C., Bailey, Brooke L., Saenz, Catherine, Anderson, Jeffrey M., Craig, Stuart A. S., Kraemer, William J., Volek, Jeff S., Maresh, Carl M.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Betaine - administration & dosage; Biomedical and Life Sciences; Biomedicine; Cross-Over Studies; Dietary Supplements; Double-Blind Method; Endocrine System - drug effects; Endocrine System - metabolism; Exercise - physiology; Gastrointestinal Agents - administration & dosage; Hormones; Human performance; Human Physiology; Humans; Insulin; Insulin-like growth factors; Kinases; Male; Metabolism - drug effects; Nutrition; Occupational Medicine/Industrial Medicine; Original Article; Phosphorylation; Physical Exertion - drug effects; Physical Exertion - physiology; Placebos; Protein synthesis; Proteins; Proto-Oncogene Proteins c-akt - metabolism; Signal Transduction - drug effects; Sports Medicine; Time Factors; Young Adult
• ISSN: 1439-6319; 1439-6327
• DOI: 10.1007/s00421-012-2492-8

Our aim was to examine the effect of betaine supplementation on selected circulating hormonal measures and Akt muscle signaling proteins after an acute exercise session. Twelve trained men (age 19.7 ± 1.23 years) underwent 2 weeks of supplementation with either betaine (B) (1.25 g BID) or placebo (P). Following a 2-week washout period, subjects underwent supplementation with the other treatment (B or P). Before and after each 2-week period, subjects performed an acute exercise session (AES). Circulating GH, IGF-1, cortisol, and insulin were measured. Vastus lateralis samples were analyzed for signaling proteins (Akt, p70 S6k, AMPK). B (vs. P) supplementation approached a significant increase in GH (mean ± SD (Area under the curve, AUC), B: 40.72 ± 6.14, P: 38.28 ± 5.54, p  = 0.060) and significantly increased IGF-1 (mean ± SD (AUC), B: 106.19 ± 13.45, P: 95.10 ± 14.23, p  = 0.010), but significantly decreased cortisol (mean ± SD (AUC), B: 1,079.18 ± 110.02, P: 1,228.53 ± 130.32, p  = 0.007). There was no difference in insulin (AUC). B increased resting Total muscle Akt ( p  = 0.003). B potentiated phosphorylation (relative to P) of Akt (Ser 473 ) and p70 S6 k (Thr 389 ) ( p  = 0.016 and p  = 0.005, respectively). Phosphorylation of AMPK (Thr 172 ) decreased during both treatments (both p  = 0.001). Betaine (vs. placebo) supplementation enhanced both the anabolic endocrine profile and the corresponding anabolic signaling environment, suggesting increased protein synthesis.