Protein thiol oxidation and muscle contractile performance

Gui Lim

    Research output: ThesisDoctoral Thesis

    192 Downloads (Pure)


    [Truncated] There is mounting evidence that reactive oxygen species (ROS) play an important role in the development of muscle fatigue. Some of the proposed mechanisms involve the reversible thiol oxidation of muscle proteins as well as ROS-induced protein carbonylation. Although the functions of several muscle proteins have been reported to be affected by these processes, it still remains to be determined whether the thiol oxidation levels of these and other proteins increase with fatiguing muscle stimulation, and whether this is an important mechanism of ROS-mediated muscle fatigue. It was the primary objective of this thesis to address these issues using isolated extensor digitorum longus (EDL) muscles from male Wistar rats, ARC(s) mice and Ins2Akita diabetic mice.

    Using EDL muscle preparations from rats, this thesis provides evidence that reversible protein thiol oxidation plays a more important role than protein carbonylation in muscle fatigue. Firstly, total protein thiol oxidation level increases in response to fatiguing stimulation, but not following sustained non-fatiguing stimulation. Secondly, unlike protein carbonylation responses, the recovery of muscle contractile performance after fatiguing stimulation is accompanied by a return of total protein thiol oxidation to pre-stimulation level. Thirdly, both muscle fatigue and total protein thiol oxidation level are more pronounced when fatiguing stimulation takes place in the presence of the thiol oxidising agent, diamide. Fourthly, muscle contraction performed with the thiol reducing agent, dithiotreitol (DTT), decreases the magnitude of both muscle fatigue and total protein thiol oxidation level without affecting protein carbonylation level. The muscle proteins targeted by reversible protein thiol oxidation include the contractile proteins, actin, myosin, troponin and tropomyosin.
    Original languageEnglish
    QualificationDoctor of Philosophy
    Publication statusUnpublished - 2012


    Dive into the research topics of 'Protein thiol oxidation and muscle contractile performance'. Together they form a unique fingerprint.

    Cite this