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Study · Measured the body's own peptide · 2008

2 results

Co-expression of IGF-1 family members with myogenic regulatory factors following acute damaging muscle-lengthening contractions in humans.

McKay BR, O'Reilly CE, Phillips SM, Tarnopolsky MA, Parise G

The Journal of physiology25 Sept 2008Cited by 119 (Europe PMC)

PMID18818249 (opens in a new tab)DOI10.1113/jphysiol.2008.160176 (opens in a new tab)PepBankPUB-18818249
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Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study2

No result from this study comes from a test of the peptide.

Natural levels measured2

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

  1. 01HumanEndogenous levelNon-randomized trialMechanism

    In eight adults, muscle MGF mRNA expression peaked 24 h after 300 damaging lengthening contractions of the knee extensors.

    In plain wordsIn eight people, damaging muscle exercise raised the body's own MGF gene activity, which peaked at 24 hours.

    Peptide
    MGF / PEG-MGF
    Outcome
    IncreaseMuscle MGF mRNA after lengthening contractions
    Study

    n = 8

    Outcome group
    Muscle injury and repair · Musculoskeletal

    Source sentences

    Summary
    MGF mRNA expression peaked at T24 (P = 0.005).
    2 context sentences
    Summary · context
    Eight subjects (20.6 +/- 2.1 years; 81.4 +/- 9.8 kg) performed 300 lengthening contractions (180 deg s(-1)) of their knee extensors in one leg on a dynamometer.
    Summary · context
    Blood and muscle samples were collected before and at 4 (T4), 24 (T24), 72 (T72) and 120 h (T120) post-exercise.

    This result measures the body's own MGF / PEG-MGF. Nobody was given the peptide. It is not evidence about taking it.

  2. 02HumanEndogenous levelNon-randomized trialMechanism

    In eight adults after damaging lengthening contractions, Myf5 expression correlated strongly with the increase in MGF mRNA (r2 = 0.83).

    In plain wordsIn eight people after muscle damage, a rise in Myf5 tracked closely with the rise in the body's own MGF gene activity.

    Peptide
    MGF / PEG-MGF
    Outcome
    Not applicableCorrelation of Myf5 expression with MGF mRNA
    Study

    n = 8

    Outcome group
    Muscle injury and repair · Musculoskeletal

    Measurements

    r2 Myf5 with MGF mRNA
    0.83
    after lengthening contractions

    Source sentences

    Summary
    Myf5 expression strongly correlated with the increase in MGF mRNA (r(2) = 0.83; P = 0.03)
    2 context sentences
    Summary · context
    Eight subjects (20.6 +/- 2.1 years; 81.4 +/- 9.8 kg) performed 300 lengthening contractions (180 deg s(-1)) of their knee extensors in one leg on a dynamometer.
    Summary · context
    Blood and muscle samples were collected before and at 4 (T4), 24 (T24), 72 (T72) and 120 h (T120) post-exercise.

    This result measures the body's own MGF / PEG-MGF. Nobody was given the peptide. It is not evidence about taking it.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    13 Oct 2026, 21:44 UTC

    Study results updated

  2. Version 1

    13 Oct 2026, 16:31 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

Publication types

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