Signaling – Roles in Lipid Storage (Adipose and Liver) – Roles in Muscle FuncMon (OxidaMve Capacity) 2. Stress Hormones and the RegulaMon of Adiposity and Insulin Resistance
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−1500 −1000 −500 0 Low Protein High Protein Change in Energy Expenditure (kJ/day) 0 500 1000 1500 2000 Insights from Diet ComposiMon Weight Loss Study Overfeeding Study Modified from C. B. Ebbeling et al. Effects of dietary composiMon on energy expenditure during weight-‐loss maintenance., JAMA 307, 2627–34 (2012). Modified from G. A. Bray et al, Effect of dietary protein content on weight gain, energy expenditure, and body composiMon during overeaMng: a randomized controlled trial., JAMA 307, 47–55 (2012).
Weights iWAT eWAT Fat Pad Mass (mg) 0 500 1000 1500 Control Diet High Protein Diet Quadriceps Triceps surae Heart Muscle Weight (mg) 0 100 200 300 400 500 Control Diet High Protein Diet 0 2 4 6 8 10 0 2 4 6 8 Weeks Total Fat Mass (g) Control Diet High Protein Diet
Fed No AA Refed AA S6 Phosphorylation pS6/S6 0.0 0.2 0.4 0.6 0.8 1.0 Fed No AA Refed AA Akt Phosphorylation pAkt/Akt 0.0 0.5 1.0 1.5 2.0 Fed No AA Refed AA TSC2 Phosphorylation pTSC2/TSC2 0.0 0.2 0.4 0.6 0.8 1.0
1. Promotes growth of new muscle Mssue 2. Metabolic effects on exisMng muscle Mssue I. Hakield, I. Harvey, E. R. Yates, J. R. Redd, L. T. Reiter, D. Bridges, The role of TORC1 in muscle development in Drosophila., Sci. Rep. 5, 9676 (2015).
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