Mechanism of glycogen supercompensation in rat skeletal muscle cultures

Liaman K. Mamedova, Vladimir Shneyvays, Abram Katz, Asher Shainberg

Research output: Contribution to journalArticlepeer-review

23 Scopus citations

Abstract

A model to study glycogen supercompensation (the significant increase in glycogen content above basal level) in primary rat skeletal muscle culture was established. Glycogen was completely depleted in differentiated myotubes by 2 h of electrical stimulation or exposure to hypoxia during incubation in medium devoid of glucose. Thereafter, cells were incubated in medium containing glucose, and glycogen supercompensation was clearly observed in treated myotubes after 72 h. Peak glycogen levels were obtained after 120 h, averaging 2.5 and 4 fold above control values in the stimulated- and hypoxia-treated cells, respectively. Glycogen synthase activity increased and phosphorylase activity decreased continuously during 120 h of recovery in the treated cells. Rates of 2-deoxyglucose uptake were significantly elevated in the treated cells at 96 and 120 h, averaging 1.4-2 fold above control values. Glycogenin content increased slightly in the treated cells after 48 h (1.2 fold vs. control) and then increased considerably, achieving peak values after 120 h (2 fold vs. control). The results demonstrate two phases of glycogen supercompensation: the first phase depends primarily on activation of glycogen synthase and inactivation of phosphorylase; the second phase includes increases in glucose uptake and glycogenin level.

Original languageEnglish
Pages (from-to)11-19
Number of pages9
JournalMolecular and Cellular Biochemistry
Volume250
Issue number1-2
DOIs
StatePublished - Aug 2003

Bibliographical note

Funding Information:
We thank A. Isaac and T. Zinman for their valuable technical assistance. This research was supported by grants from the Israel Science Foundation (Grant No. 373/98-18.1) (AS) and the Swedish National Center for Sports (AK).

Funding

We thank A. Isaac and T. Zinman for their valuable technical assistance. This research was supported by grants from the Israel Science Foundation (Grant No. 373/98-18.1) (AS) and the Swedish National Center for Sports (AK).

FundersFunder number
Swedish National Center for Sports
Israel Science Foundation373/98-18.1

    Keywords

    • Glycogen phosphorylase
    • Glycogen synthase
    • Glycogenin

    Fingerprint

    Dive into the research topics of 'Mechanism of glycogen supercompensation in rat skeletal muscle cultures'. Together they form a unique fingerprint.

    Cite this