Sarcopenia — Insulin and Sarcopenia in the Elderly
Citation(s)
Bell JA, Fujita S, Volpi E, Cadenas JG, Rasmussen BB Short-term insulin and nutritional energy provision do not stimulate muscle protein synthesis if blood amino acid availability decreases. Am J Physiol Endocrinol Metab. 2005 Dec;289(6):E999-1006.
Dreyer HC, Volpi E Role of protein and amino acids in the pathophysiology and treatment of sarcopenia. J Am Coll Nutr. 2005 Apr;24(2):140S-145S. Review.
Fujita S, Glynn EL, Timmerman KL, Rasmussen BB, Volpi E Supraphysiological hyperinsulinaemia is necessary to stimulate skeletal muscle protein anabolism in older adults: evidence of a true age-related insulin resistance of muscle protein metabolism. Diab
Fujita S, Rasmussen BB, Cadenas JG, Grady JJ, Volpi E Effect of insulin on human skeletal muscle protein synthesis is modulated by insulin-induced changes in muscle blood flow and amino acid availability. Am J Physiol Endocrinol Metab. 2006 Oct;291(4):E7
Fujita S, Volpi E Amino acids and muscle loss with aging. J Nutr. 2006 Jan;136(1 Suppl):277S-80S. Review.
Timmerman KL, Volpi E Amino acid metabolism and regulatory effects in aging. Curr Opin Clin Nutr Metab Care. 2008 Jan;11(1):45-9. Review.
Volpi E, Chinkes DL, Rasmussen BB Sequential muscle biopsies during a 6-h tracer infusion do not affect human mixed muscle protein synthesis and muscle phenylalanine kinetics. Am J Physiol Endocrinol Metab. 2008 Oct;295(4):E959-63. doi: 10.1152/ajpendo.0
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.
