DLR-Logo -> http://www.dlr.de
DLR Portal Home | Imprint | Privacy Policy | Contact | Deutsch
Fontsize: [-] Text [+]

Anabolic resistance assessed by oral stable isotope ingestion following bed rest in young and older adult volunteers: Relationships with changes in muscle mass

Biolo, G. and Pišot, R. and Mazzucco, S. and Di Girolamo, F.G. and Situlin, R. and Lazzer, S. and Grassi, B. and Reggiani, C. and Passaro, A. and Rittweger, Jörn and Gasparini, M. and Simunic, B. and Narici, M. (2017) Anabolic resistance assessed by oral stable isotope ingestion following bed rest in young and older adult volunteers: Relationships with changes in muscle mass. Clinical Nutrition, 36 (5), pp. 1420-1426. Elsevier. doi: 10.1016/j.clnu.2016.09.019. ISSN 0261-5614.

Full text not available from this repository.


Background & aims Aging and experimental bed rest are associated with muscle atrophy and resistance to post-prandial stimulation of protein synthesis or anabolic resistance (AR). We have used in young and older adult volunteers, during short-term bed rest, a quick and non-invasive method, based on a single oral bolus of the stable isotope L[ring-2H5]phenylalanine (D5Phe), to determine post-prandial AR, defined as ratio between irreversible hydroxylation and incorporation into body protein of ingested phenylalanine. Methods We compared in older (O, 59 ± 1 y) and young (Y, 23 ± 1 y) healthy male volunteers the effects of two-week bed rest on post-prandial protein kinetics, assessed during absorption of a standard ready-to-use oral nutritional supplement, through stable-labeled isotope amino acid D5Phe, diluted in water, given as single oral load. The metabolic fate of D5Phe is either utilization for protein synthesis or irreversible hydroxylation to L[ring-2H4]tyrosine (D4Tyr). AR was defined as ratio between the areas under the curves of D4Tyr-to-D5Phe plasma concentrations over 6 h meal absorption. To determine the relationships between AR and muscle changes following bed rest, quadriceps muscle volume (QMV) was determined by magnetic resonance imaging (MRI). Results At baseline, in pooled Y and O subjects, values of AR were inversely correlated with QMV (R = −0.75; p < 0.03). Following 2-weeks of inactivity, there were significant bed rest effects on AR (p < 0.01) and QMV (p < 0.03), as well as significant bed rest × group interaction for AR (p < 0.03; +9.2% in Y; +21.9% in O) and QMV (p < 0.05; −5.7% in Y; −%7.3 in O). In pooled subjects, the percentage delta changes in AR and QMV, induced by bed rest, were inversely correlated (R = −0.57; p < 0.05). Conclusion Bed rest-induced AR is much greater in the older than in younger adults. We have developed a new, simple, non-invasive method for the assessment of AR. The results indicate that this metabolic abnormality is a key mechanism for sarcopenia of aging and inactivity.

Item URL in elib:https://elib.dlr.de/113882/
Document Type:Article
Title:Anabolic resistance assessed by oral stable isotope ingestion following bed rest in young and older adult volunteers: Relationships with changes in muscle mass
AuthorsInstitution or Email of AuthorsAuthor's ORCID iDORCID Put Code
Biolo, G.University of TriesteUNSPECIFIEDUNSPECIFIED
Pišot, R.university of primorskaUNSPECIFIEDUNSPECIFIED
Mazzucco, S.university of triesteUNSPECIFIEDUNSPECIFIED
Di Girolamo, F.G.University of TriesteUNSPECIFIEDUNSPECIFIED
Situlin, R.University of TriesteUNSPECIFIEDUNSPECIFIED
Lazzer, S.university of udineUNSPECIFIEDUNSPECIFIED
Grassi, B.university of udine, italyUNSPECIFIEDUNSPECIFIED
Reggiani, C.university of padua, italyUNSPECIFIEDUNSPECIFIED
Rittweger, JörnUNSPECIFIEDhttps://orcid.org/0000-0002-2223-8963UNSPECIFIED
Gasparini, M.general hospital izola, sloveniaUNSPECIFIEDUNSPECIFIED
Simunic, B.university of primorskaUNSPECIFIEDUNSPECIFIED
Narici, M.manchester metropolitan university, u.k.UNSPECIFIEDUNSPECIFIED
Journal or Publication Title:Clinical Nutrition
Refereed publication:Yes
Open Access:No
Gold Open Access:No
In ISI Web of Science:Yes
Page Range:pp. 1420-1426
Keywords:Anabolic resistance; Isotopic tracers; Skeletal muscle; Muscle atrophy; Bed rest; Aging
HGF - Research field:Aeronautics, Space and Transport
HGF - Program:Space
HGF - Program Themes:Research under Space Conditions
DLR - Research area:Raumfahrt
DLR - Program:R FR - Research under Space Conditions
DLR - Research theme (Project):R - Vorhaben Systemphysiologie (old)
Location: Köln-Porz
Institutes and Institutions:Institute of Aerospace Medicine > Muscle and Bone Metabolism
Deposited By: Becker, Christine
Deposited On:05 Sep 2017 15:53
Last Modified:06 Sep 2019 15:19

Repository Staff Only: item control page

Help & Contact
electronic library is running on EPrints 3.3.12
Website and database design: Copyright © German Aerospace Center (DLR). All rights reserved.