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Enzymatically dissociated muscle fibers display rapid dedifferentiation and impaired mitochondrial calcium control.

ABSTRACT: Cells rapidly lose their physiological phenotype upon disruption of their extracellular matrix (ECM)-intracellular cytoskeleton interactions. By comparing adult mouse skeletal muscle fibers, isolated either by mechanical dissection or by collagenase-induced ECM digestion, we investigated acute effects of ECM disruption on cellular and mitochondrial morphology, transcriptomic signatures, and Ca²⁺ handling. RNA-sequencing showed striking differences in gene expression patterns between the two isolation methods with enzymatically dissociated fibers resembling myopathic phenotypes. Mitochondrial appearance was grossly similar in the two groups, but 3D electron microscopy revealed shorter and less branched mitochondria following enzymatic dissociation. Repeated contractions resulted in a prolonged mitochondrial Ca²⁺ accumulation in enzymatically dissociated fibers, which was partially prevented by cyclophilin inhibitors. Of importance, muscle fibers of mice with severe mitochondrial myopathy show pathognomonic mitochondrial Ca²⁺ accumulation during repeated contractions and this accumulation was concealed with enzymatic dissociation, making this an ambiguous method in studies of native intracellular Ca²⁺ fluxes.

SUBMITTER: Gineste C

PROVIDER: S-EPMC9720020 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Enzymatically dissociated muscle fibers display rapid dedifferentiation and impaired mitochondrial calcium control.

Gineste Charlotte C Youhanna Sonia S Vorrink Sabine U SU Henriksson Sara S Hernández Andrés A Cheng Arthur J AJ Chaillou Thomas T Buttgereit Andreas A Schneidereit Dominik D Friedrich Oliver O Hultenby Kjell K Bruton Joseph D JD Ivarsson Niklas N Sandblad Linda L Lauschke Volker M VM Westerblad Håkan H

iScience 20221122 12

Cells rapidly lose their physiological phenotype upon disruption of their extracellular matrix (ECM)-intracellular cytoskeleton interactions. By comparing adult mouse skeletal muscle fibers, isolated either by mechanical dissection or by collagenase-induced ECM digestion, we investigated acute effects of ECM disruption on cellular and mitochondrial morphology, transcriptomic signatures, and Ca<sup>2+</sup> handling. RNA-sequencing showed striking differences in gene expression patterns between t ...[more]

PMID: 36479146

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Enzymatically dissociated muscle fibers display rapid dedifferentiation and impaired mitochondrial calcium control.

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Enzymatically dissociated muscle fibers display rapid dedifferentiation and impaired mitochondrial calcium control.

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