Dataset Information

Prolonged Exposure to Microgravity Reduces Cardiac Contractility and Initiates Remodeling in Drosophila.

ABSTRACT: Understanding the effects of microgravity on human organs is crucial to exploration of low-earth orbit, the moon, and beyond. Drosophila can be sent to space in large numbers to examine the effects of microgravity on heart structure and function, which is fundamentally conserved from flies to humans. Flies reared in microgravity exhibit cardiac constriction with myofibrillar remodeling and diminished output. RNA sequencing (RNA-seq) in isolated hearts revealed reduced expression of sarcomeric/extracellular matrix (ECM) genes and dramatically increased proteasomal gene expression, consistent with the observed compromised, smaller hearts and suggesting abnormal proteostasis. This was examined further on a second flight in which we found dramatically elevated proteasome aggregates co-localizing with increased amyloid and polyQ deposits. Remarkably, in long-QT causing sei/hERG mutants, proteasomal gene expression at 1g, although less than the wild-type expression, was nevertheless increased in microgravity. Therefore, cardiac remodeling and proteostatic stress may be a fundamental response of heart muscle to microgravity.

SUBMITTER: Walls S

PROVIDER: S-EPMC7787258 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Prolonged Exposure to Microgravity Reduces Cardiac Contractility and Initiates Remodeling in Drosophila.

Walls Stanley S Diop Soda S Birse Ryan R Elmen Lisa L Gan Zhuohui Z Kalvakuri Sreehari S Pineda Santiago S Reddy Curran C Taylor Erika E Trinh Bosco B Vogler Georg G Zarndt Rachel R McCulloch Andrew A Lee Peter P Bhattacharya Sharmila S Bodmer Rolf R Ocorr Karen K

Cell reports 20201125 10

Understanding the effects of microgravity on human organs is crucial to exploration of low-earth orbit, the moon, and beyond. Drosophila can be sent to space in large numbers to examine the effects of microgravity on heart structure and function, which is fundamentally conserved from flies to humans. Flies reared in microgravity exhibit cardiac constriction with myofibrillar remodeling and diminished output. RNA sequencing (RNA-seq) in isolated hearts revealed reduced expression of sarcomeric/ex ...[more]

PMID: 33242407

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Dataset Information

Prolonged Exposure to Microgravity Reduces Cardiac Contractility and Initiates Remodeling in Drosophila.

Publications

Prolonged Exposure to Microgravity Reduces Cardiac Contractility and Initiates Remodeling in Drosophila.

Similar Datasets

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