What question did this study set out to answer?

To determine whether sulfhydryl oxidation plays an essential role in activating the hexose transport system in isolated fat cells.

October 1, 1974Proceedings of the National Academy of SciencesOpen Access

Evidence for the Involvement of Sulfhydryl Oxidation in the Regulation of Fat Cell Hexose Transport by Insulin

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Authors

MCMichael CzechUniversity of Massachusetts Chan Medical School JLJohn C. LawrenceMonsanto (United States)WLWilliam S. LynnQueen's University Belfast

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Implication

In vitro study demonstrates that sulfhydryl oxidation mediates insulin-stimulated hexose transport in isolated fat cells, indicating transport activation requires maintenance of a disulfide state.

Key Points

To determine whether sulfhydryl oxidation plays an essential role in activating the hexose transport system in isolated fat cells.
Isolated fat cells were incubated with insulin, oxidants, reducing agents such as dithiothreitol, or the alkylating agent N-ethylmaleimide (1 mM).
Hexose transport rates were evaluated via 3-O-methylglucose uptake, and receptor binding was monitored using 125I-labeled insulin.
Cells were tested with washouts and trypsin digestion to measure transport persistence and receptor independence.
Dithiothreitol reversibly inhibited 3-O-methylglucose transport, while 1 mM N-ethylmaleimide completely blocked insulin- and oxidant-stimulated transport without altering basal activity.
Preincubation with insulin or oxidants completely protected the transport system from N-ethylmaleimide inhibition, despite a ~50% reduction in insulin receptor binding.
Treatment with N-ethylmaleimide following insulin stimulation permanently locked hexose transport in an active state, even after hormone removal or receptor destruction by trypsin.

Cite This Study

Czech et al. (1974) studied this question.

synapsesocial.com/papers/6a7d5d31da72e8de9c279bb6 https://doi.org/10.1073/pnas.71.10.4173

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Implication

In vitro study demonstrates that sulfhydryl oxidation mediates insulin-stimulated hexose transport in isolated fat cells, indicating transport activation requires maintenance of a disulfide state.

Evidence for the Involvement of Sulfhydryl Oxidation in the Regulation of Fat Cell Hexose Transport by Insulin

Discussion

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Implication

Key Points

Cite This Study

Evidence for the Involvement of Sulfhydryl Oxidation in the Regulation of Fat Cell Hexose Transport by Insulin

Discussion

Member takes

Implication

Key Points

Cite This Study

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