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Effects of Short-term Energy Deficit on Muscle Protein Turnover

14 marzo 2016 aggiornato da: Stuart M. Phillips, McMaster University
Weight loss through energy restriction results in the loss of both fat and muscle mass. Muscle mass is important for mobility, strength, glucose control and energy expenditure, and therefore the retention of muscle mass during energy restriction is an important goal. The retention of muscle mass depends on the balance between muscle protein synthesis (MPS) and muscle protein breakdown (MPB). It is well known that MPS is reduced during weight loss, however the effect of weight loss on MPB is currently a topic of debate. The purpose of this study is to assess the effect of short-term (10 day) weight loss (40% energy deficit) on both MPS and MPB in order to gain insight into the mechanisms causing muscle loss during energy restriction. In addition, the effect of resistance exercise and protein (both known to preserve muscle mass) on MPS and MPB will be examined

Panoramica dello studio

Stato

Completato

Condizioni

Intervento / Trattamento

Descrizione dettagliata

An undesirable consequence of energy restriction is the loss of muscle mass. Muscle mass is determined by the the rates of two processes: muscle protein synthesis and muscle protein breakdown. It has been consistently shown that a reduced rate of muscle protein synthesis exists during energy restriction. However, it is currently unclear whether an increase in muscle protein breakdown also contributes to muscle mass loss. In addition, the effect of high protein diets and resistance exercise on muscle protein turnover during energy restriction, two interventions known to preserve muscle, remains to be investigated.We aim to demonstrate that the decrease in muscle protein synthesis is the main contributor to a negative protein balance during energy restriction. In addition, we hope to show that a higher-protein diet (2.4g/kg/d versus 1.2g/kg/d) and the addition of resistance exercise can help to maintain the muscle protein synthesis rate and thereby improve negative protein balance.The present study will be designed as a parallel group randomized controlled trial. Subjects will be given pre-packaged diets (Copper County Foods) to consume which will put them in a relative energy deficit of 40% per day. Based on random assignment, these subjects will either consume an adequate protein diet (1.2g/kg/d) or a high protein diet (2.4g/kg/d) for 10 consecutive days. Participants in the adequate protein diet will consume a ratio of 50:35:15 (carbohydrates:fat:protein) while subjects within the high protein diet will consume a ratio of 50:15:35 (carbohydrates:fat:protein). Subjects will undergo testing at baseline and following a 10 day dietary and unilateral resistance exercise intervention. Testing will consist of muscle and blood samples. Muscle protein synthesis and muscle protein breakdown will be measured using stable isotope tracers that are orally ingested (deuterated water) or infused into an antecubital vein (labelled phenylalanine tracers) before and after the 10 day diet.

Tipo di studio

Interventistico

Iscrizione (Effettivo)

24

Fase

  • Non applicabile

Contatti e Sedi

Questa sezione fornisce i recapiti di coloro che conducono lo studio e informazioni su dove viene condotto lo studio.

Luoghi di studio

    • Ontario
      • Hamilton, Ontario, Canada, L8S 4K1
        • Exercise Metabolism Research Laboratory, McMaster Univeristy

Criteri di partecipazione

I ricercatori cercano persone che corrispondano a una certa descrizione, chiamata criteri di ammissibilità. Alcuni esempi di questi criteri sono le condizioni generali di salute di una persona o trattamenti precedenti.

Criteri di ammissibilità

Età idonea allo studio

Da 20 anni a 30 anni (Adulto)

Accetta volontari sani

Sessi ammissibili allo studio

Maschio

Descrizione

Inclusion Criteria:

  • Between the ages of 20 and 30 years inclusive
  • Have a BMI between 25 and 33 inclusive

Exclusion Criteria:

  • Have a body mass index less than 25 kg/m2 or greater than 33 kg/m2.
  • Vegan
  • History of allergy, sensitivity, or strong dislike towards dairy protein
  • Smoker or user of tobacco products
  • High physical activity
  • Have health problems such as: renal or gastrointestinal disorders, metabolic disease, heart disease, vascular disease, rheumatoid arthritis, diabetes, poor lung function, uncontrolled blood pressure, dizziness, thyroid problems, or any other health conditions for which volunteers are being treated that might put them at risk for this study.
  • Taking anti-diabetic, anti-inflammatory, platelet inhibitor, or anti-coagulant medications
  • Use of an investigational drug product within the last 30 days
  • Have participated in an infusion protocol in the last year
  • Do not understand English or have a condition the PI believes would interfere with the ability to provide informed consent, comply with the study protocol, or which might confound the interpretation of the study results or put volunteers at undue risk

Piano di studio

Questa sezione fornisce i dettagli del piano di studio, compreso il modo in cui lo studio è progettato e ciò che lo studio sta misurando.

Come è strutturato lo studio?

Dettagli di progettazione

  • Scopo principale: Scienza basilare
  • Assegnazione: Randomizzato
  • Modello interventistico: Assegnazione parallela
  • Mascheramento: Separare

Armi e interventi

Gruppo di partecipanti / Arm
Intervento / Trattamento
Sperimentale: High Protein
2.4g protein/kg/d. The macronutrient composition will be 50:15:35 (carbohydrates:fat:protein) during Energy Restriction
All meals will be provided for the duration of the energy restriction intervention and the energy deficit will be calculated based on estimated energy requirements by indirect calorimetry to provide 60% of energy requirements. In addition, one leg will be assigned to perform resistance exercise for 5 days during the 10 day energy deficit.
Sperimentale: Adequate Protein
1.2g protein/kg/d. The macronutrient composition will be 50:35:15 (carbohydrates:fat:protein) during Energy Restriction
All meals will be provided for the duration of the energy restriction intervention and the energy deficit will be calculated based on estimated energy requirements by indirect calorimetry to provide 60% of energy requirements. In addition, one leg will be assigned to perform resistance exercise for 5 days during the 10 day energy deficit.

Cosa sta misurando lo studio?

Misure di risultato primarie

Misura del risultato
Misura Descrizione
Lasso di tempo
Muscle protein turnover
Lasso di tempo: Baseline and 10 days
Change in muscle protein synthesis and muscle protein breakdown before and after the weight loss diet will be assessed. The relationship between high protein diets (parallel groups) and exercise (unilateral resistance exercise) on muscle protein turnover will also be examined. Muscle protein synthesis and muscle protein breakdown will be measured with stable isotope infusions of labelled phenylalanine tracers before and after the 10 day diet. In addition, long term muscle protein synthesis will be measured with orally ingested deuterated water.
Baseline and 10 days

Misure di risultato secondarie

Misura del risultato
Misura Descrizione
Lasso di tempo
Molecular markers
Lasso di tempo: Baseline and 10 days
Change in the the transcriptional expression of genes involved in the ubiquitin-proteasome pathway (main regulator of muscle protein breakdown) measured in muscle samples obtained at baseline and following the 10 day dietary intervention by quantitative polymerase chain reaction (qPCR). These same samples will be analyzed by western blot for the expression of active and inactive isoforms of caspase-3, an important component of muscle protein breakdown. Finally, immunoprecipitation and western blot will be used to examine the ubiquitination of translation initiation factors at baseline and following the 10 day intervention
Baseline and 10 days

Collaboratori e investigatori

Qui è dove troverai le persone e le organizzazioni coinvolte in questo studio.

Pubblicazioni e link utili

La persona responsabile dell'inserimento delle informazioni sullo studio fornisce volontariamente queste pubblicazioni. Questi possono riguardare qualsiasi cosa relativa allo studio.

Studiare le date dei record

Queste date tengono traccia dell'avanzamento della registrazione dello studio e dell'invio dei risultati di sintesi a ClinicalTrials.gov. I record degli studi e i risultati riportati vengono esaminati dalla National Library of Medicine (NLM) per assicurarsi che soddisfino specifici standard di controllo della qualità prima di essere pubblicati sul sito Web pubblico.

Studia le date principali

Inizio studio

1 giugno 2015

Completamento primario (Effettivo)

1 gennaio 2016

Completamento dello studio (Effettivo)

1 gennaio 2016

Date di iscrizione allo studio

Primo inviato

28 marzo 2015

Primo inviato che soddisfa i criteri di controllo qualità

28 marzo 2015

Primo Inserito (Stima)

1 aprile 2015

Aggiornamenti dei record di studio

Ultimo aggiornamento pubblicato (Stima)

16 marzo 2016

Ultimo aggiornamento inviato che soddisfa i criteri QC

14 marzo 2016

Ultimo verificato

1 marzo 2016

Maggiori informazioni

Termini relativi a questo studio

Altri numeri di identificazione dello studio

  • Not assigned (Charles A. Dana Foundation Brain and Immuno-Imaging Grant)

Queste informazioni sono state recuperate direttamente dal sito web clinicaltrials.gov senza alcuna modifica. In caso di richieste di modifica, rimozione o aggiornamento dei dettagli dello studio, contattare register@clinicaltrials.gov. Non appena verrà implementata una modifica su clinicaltrials.gov, questa verrà aggiornata automaticamente anche sul nostro sito web .

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