Role of Dietary Protein in the Sarcopenia of Aging. Activity. Douglas Paddon-Jones, Ph.D., FACSM. Conceptual Model.. Drug therapies.

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1 Role of Dietary Protein in the Sarcopenia of Aging Douglas Paddon-Jones, Ph.D., FACSM Lorenz Distinguished Professor in Aging and Health Department of Nutrition and Metabolism The University of Texas Medical Branch Disclosures Conceptual Model.. Inactivityty Dr. Paddon-Jones is a Research Investigator with current funding from the National Institute of Health (NIH) and the Dairy Research Institute. Disease Inflammation Dr. Paddon-Jones is a member of the Scientific Advisory Board or provides education seminars for the National Dairy Council, American Egg Board, National Cattlemens Beef Association and Leprino Foods. Mitochondrial ial Dysfunction Inadequate ate Nutrition Aging Activity Drug therapies Blood Flow

2 Recommended Dietary Allowance (RDA) How much protein need, want or desire? RDA: estimate of the minimum daily average dietary intake level that meets the nutrient requirements of 97-98% of healthy individuals RDA for protein:.8 g of good quality protein / kg body weight / day Minimum Dietary Allowance (MDA)? Consequences of too much or too little protein? Anabolic response to whole-food protein High Risk Low Risk Muscle loss Strength loss Bone density Crisis response Cancer? Kidney function? Bone density? Fat gain Low RDA Moderate High Protein Consumption Extreme References: Symons et. al. AJCN, 27 Symons et. al. JADA. 29

3 Synergistic Effect of Protein and Exercise Reality: Age-related dose-response Protein Synthesis (%/h) % increase 5% increase Fasting * * Protein meal * * Protein + Exercise Young Elderly 6 g 5 g 8 g 6 g Reference: Symons et. al. JNHA, 21 Reference: Katsanos et. al. AJCN, 25 Concept: Skewed / typical protein intake Humans can t store excess protein for later anabolism Catabolism Anabolism 1 g 15 g 65 g Catabolism Anabolism 1 g X 15 g 65 g average adult in US: 6-1 g protein/day ( g /kg/day) Reference: Paddon-Jones and Rasmussen 29 Reference: Paddon-Jones and Rasmussen 29

4 Concept: Optimizing protein at each meal? Protein distribution impacts muscle protein synthesis Catabolism Anabolism g * 25% * g Older (?) à age energy requirements...protein quality...body composition goals...satiety Reference: Paddon-Jones and Rasmussen 29 Reference: Mamerow, et.al. J. Nutr. 214 Sarcopenia Sarcopenia and protecting muscle during inactivity / illness Sarcopenia is a syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength with a risk of adverse outcomes such as physical disability, poor quality of life and death. Cruz-Jentoft AJ et al. Sarcopenia: European consensus on definition and diagnosis. Report of the European Working Group on Sarcopenia in Older People. Age Ageing 21

5 Typical "uncomplicated sarcopenia Catabolic crisis model Muscle mass (kg) Muscle mass (kg) Age (yrs) Age (yrs) Reference : English and Paddon-Jones. Curr Opin Clin Nutr Metab Care. 21 Reference : English and Paddon-Jones. Curr Opin Clin Nutr Metab Care. 21 If you are hospitalized - you are put in bed Inactivity and Muscle Loss - Bed Rest - % Time Inactive ( steps/min) Low Activity (< 15 steps/min) Loss of lean leg mass (g) Young Middle-aged Older 28 Days 14 Days 1 Days best case situation Older Patients 4 Days Paddon-Jones et. al. 24 English et al., 214 Kortebein et al. 27 Paddon-Jones, Pilot Data

6 Protecting Muscle with Nutrition Leucine: partially protects muscle function Leucine has a key regulatory role on muscle protein synthesis are the benefits overstated? should you recommend a leucine supplement? Percentage change % Knee extension endurance Aerobic capacity (VO2max) Knee extension strength/torque Control Leucine English, et al. 215 AJCN Leucine: partially / temporarily protects muscle mass Leucine content of food Whole body lean mass (g) Day 7 (mid-point) Day 14 (end bed rest) Control Leucine Protein source Leucine whey protein isolate 12 % milk protein 1 % egg protein 8.5 % muscle protein 8 % soy protein isolate 8 % collagen 2 % English, et al. 215 AJCN

7 Protein Quality: Limiting amino acids: - lysine - methionine & cysteine (soy) Single source protein supplements: Clinical / Practical Relevance? q Whey q Casein q Soy q Blends q Milk protein - methionine / tryptophan - lysine + methionine + + lysine - methionine = * but how much?? q Collagen ( - tryptophan; + arginine) q Rice ( - lysine) q Pea ( - methionine; - cysteine) * note: low protein quality poor nutrition quality Summary and recommendations Recommendations For all adults. Remember, the RDA is a minimum, not an upper limit. Establish a dietary framework that includes a moderate amount of high quality protein (or combination) at each meal. Modify as necessary to accommodate individual needs: - energy requirements - physical activity - health status - body composition goals - dentition, satiety

8 Recommendations React aggressively with targeted protein interventions to preserve muscle health and reduce negative metabolic consequences of physical inactivity, illness or injury Paddon-Jones Lab Emily Arentson-Lantz Elfego Galvan Medical Team Adam Wacher Elena Volpi Charles Mathers Colleagues ITS-CRC Nursing & Bionutrition Staff Blake Rasmussen Wayne Campbell / Heather Leidy Don Layman Thomas Lang Aaron Russell / Severine Lamon Funding RO1 NR12973 R21 AR62479 NSBRI (NNJ8ZSA2N) National Cattlemens Beef Association National Dairy Council UTMB Claude D. Pepper Older Americans Independence Center