CoChat
Sign Up
Cited by 464Muscle metabolism and nutritionNutrition and Health in AgingMuscle Physiology and Disorders

The Response of Muscle Protein Anabolism to Combined Hyperaminoacidemia and Glucose-Induced Hyperinsulinemia Is Impaired in the Elderly1

Open access
Volpi, Elena, Mittendorfer, Bettina, Rasmussen, Blake B., Wolfe, Robert R.·2000·The Journal of Clinical Endocrinology & Metabolism
DOI 10.1210/jcem.85.12.7021PMC PMC3192447
Open this paper in CoChat — free accountOpen PDF

Abstract

Muscle mass declines with aging. Amino acids alone stimulate muscle protein synthesis in the elderly. However, mixed nutritional supplementation failed to improve muscle mass. We hypothesized that the failure of nutritional supplements is due to altered responsiveness of muscle protein anabolism to increased amino acid availability associated with endogenous hyperinsulinemia. We measured muscle protein synthesis and breakdown, and amino acid transport in healthy young (30 +/- 3 yr) and elderly (72 +/- 1 yr) volunteers in the basal postabsorptive state and during the administration of an amino acid-glucose mixture, using L-[ring-(2)H(5)]phenylalanine infusion, femoral artery and vein catheterization, and muscle biopsies. Basal muscle amino acid turnover was similar in young and elderly subjects. The mixture increased phenylalanine leg delivery and transport into the muscle in both groups. Phenylalanine net balance increased in both groups (young, -27 +/- 8 to 64 +/- 17; elderly, -16 +/- 4 to 29 +/- 7 nmol/(min.100 mL); P: < 0.0001, basal vs. mixture), but the increase was significantly blunted in the elderly (P: = 0.030 vs. young). Muscle protein synthesis increased in the young, but remained unchanged in the elderly [young, 61 +/- 17 to 133 +/- 30 (P: = 0. 005); elderly, 62 +/- 9 to 70 +/- 14 nmol/(min.100 mL) (P: = NS)]. In both groups, protein breakdown decreased (P: = 0.012) and leg glucose uptake increased (P: = 0.0258) with the mixture. We conclude that the response of muscle protein anabolism to hyperaminoacidemia with endogenous hyperinsulinemia is impaired in healthy elderly due to the unresponsiveness of protein synthesis.

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Integrity signals

Registry

Crossref · 10.1210/jcem.85.12.7021

Cites

5 of 5 references verified0 citation errors · 0 not checkable

Statistics

Claims the paper makes

The claims and statistics of this paper haven’t been checked yet.

Run the check — free, no account needed. It reads the open-access text and checks the sources it cites.

A few free checks a day · papers already verified open instantly · results are public

Claims other papers make about this one

Each is checked against this paper’s own text: does it say what the citing paper says it does?

  • In the fed state, most researchers agree there is an impairment of the muscle protein anabolic response to meal intake in older adults, although some studies found no difference, especially with high amino acid or protein amounts.

    “In the fed state, however, most researchers now agree that there is an impairment of the muscle protein anabolic response to meal intake in older adults, 46,49,50 although some studies found no difference between older and younger adults, especially when high amounts of amino acids or proteins were administered.”

    From Evidence-Based Recommendations for Optimal Dietary Protein Intake in Older People: A Position Paper From the PROT-AGE Study Group (2013) · cites this paper as [49]

  • In young and older adults following a simulated protein/carbohydrate mixed meal, muscle protein breakdown did not change in either age group, but muscle protein synthesis increased only in the young.

    “Consistent with the anabolic resistance hypothesis, muscle protein breakdown did not change in either age-group, however, muscle protein synthesis increased only in the young.”

    From Protecting muscle mass and function in older adults during bed rest (2010) · cites this paper as [18]

Self-check

Percentages, sums and reported differences re-computed from the paper’s own numbers.

The self-check needs the paper’s full text.

Cites

Flagged first, then by citations

Research works printed but not linked: 4

  1. Wolfe RR, Volpi E. 2000 Insulin and protein metabolism. In: Jefferson LS, Cherrington AD, eds. Handbook of physiology. New York: Oxford University Press; vol 2:733-755.
  2. Wolfe RR. 1992 Appendix A: laboratory methods. In: Radioactive and stable isotope tracers in biomedicine. Principle and practice of kinetic analysis. New York: Wiley-Liss; 417-438.
  3. Wolfe RR. 1992 Calculation of substrate kinetics: single pool model. In: Ra- dioactive and stable isotope tracers in biomedicine. Principle and practice of kinetic analysis. New York: Wiley-Liss; 119 -144.
  4. Welle S, Thornton C, Jozefowicz R, Statt M. 1993 Myofibrillar protein syn- thesis in young and old men. Am J Physiol. 264:E693-E698.

Cited by

Sorted by citations

Authors
Volpi, E., Mittendorfer, B., Rasmussen, B. B., & Wolfe, R. R.
Affiliations
Shriners Hospitals for Children - Galveston (US)
ORCID
Venue
The Journal of Clinical Endocrinology & Metabolism
Publisher
The Endocrine Society
Published
2000-12
Volume
85
Issue
12
Pages
4481-4490
ISSN
  • 0021-972X (ISSN-L)
  • 1945-7197
DOI
10.1210/jcem.85.12.7021
PMC
PMC3192447
OpenAlex
W2028767281
Cited by
464
References
5
Citations by year
2026: 1 · 2025: 10 · 2024: 9 · 2023: 13 · 2022: 14 · 2021: 16 · 2020: 13 · 2019: 16 · 2018: 16 · 2017: 11 · 2016: 27 · 2015: 34 · 2014: 17 · 2013: 27 · 2012: 36
FWCI
2.57
Type
journal article
Language
en
Open access
Licence
public-domain
Locations
  • The Journal of Clinical Endocrinology & Metabolism (publishedVersion, public-domain)
  • PubMed (publishedVersion)
  • Europe PMC (PubMed Central) (acceptedVersion)
  • PubMed Central (acceptedVersion)
Funders
  • Shriners Hospitals for Children
  • National Institutes of Health (RR-00073)
  • U.S. Public Health Service
  • National Institute on Aging (AG-15780, R01AG015780, P60 AG 17231, P60AG017231, R01AG018311, P30AG024832)
  • National Center for Research Resources (M01 RR-00073, M01RR000073)
Topics
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Cell Biology › Muscle metabolism and nutrition
  • Health Sciences › Medicine › Physiology › Nutrition and Health in Aging
  • Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Muscle Physiology and Disorders
Keywords
muscle protein anabolism, hyperaminoacidemia, hyperinsulinemia, aging, older adults, muscle protein synthesis, muscle protein degradation, amino acid transport, phenylalanine, glucose uptake, muscle mass, dietary supplementation
MeSH terms
Adult, Aged, Aging, Amino Acids, Blood Glucose, Female, Glucose, Hormones, Humans, Hyperinsulinism, Leg, Male, Muscle Proteins, Regional Blood Flow, Muscle, Skeletal

About these checks

Registry, retraction, Cites and statistics results are computed, not judged, with one exception: a printed reference that no index lists is read once by a model before it counts as a citation error. Claims are extracted by a model and kept only when their quote appears verbatim in the text; each cited source is then checked, with a model’s help, for whether it says what the claim relies on. Those verdicts can be wrong — read the claim’s quote and the cited source before relying on one.

Statistics and arithmetic are recomputed, not judged.

Confidence bands are shown only for fields calibrated on our annotated test set. None is calibrated yet, so no band is shown.

What counts as a claim ›How we measure confidence ›How we check this ›

Are you an author, or do you see a problem with this page? Request a review