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Fluidics system for resolving concentration-dependent effects of dissolved gases on tissue metabolism

  1. Varun Kamat
  2. Brian M Robbings
  3. Seung-Ryoung Jung
  4. John Kelly
  5. James B Hurley
  6. Kenneth P Bube
  7. Ian R Sweet  Is a corresponding author
  1. University of Washington, United States
  2. VICI Metronics, United States
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Cite this article as: eLife 2021;10:e66716 doi: 10.7554/eLife.66716

Abstract

Oxygen (O2) and other dissolved gases such as the gasotransmitters H2S, CO and NO affect cell metabolism and function. To evaluate effects of dissolved gases on processes in tissue, we developed a fluidics system that controls dissolved gases while simultaneously measuring parameters of electron transport, metabolism and secretory function. We use pancreatic islets, retina and liver from rodents to highlight its ability to assess effects of O2 and H2S. Protocols aimed at emulating hypoxia-reperfusion conditions resolved a previously unrecognized transient spike in O2 consumption rate (OCR) following replenishment of O2, and tissue-specific recovery of OCR following hypoxia. The system revealed both inhibitory and stimulatory effects of H2S on insulin secretion rate from isolated islets. The unique ability of this new system to quantify metabolic state and cell function in response to precise changes in dissolved gases provides a powerful platform for cell physiologists to study a wide range of disease states.

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Article and author information

Author details

  1. Varun Kamat

    Department of Medicine, University of Washington, Seattle, United States
    Competing interests
    No competing interests declared.
  2. Brian M Robbings

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    No competing interests declared.
  3. Seung-Ryoung Jung

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    No competing interests declared.
  4. John Kelly

    Analytical Analysis, VICI Metronics, Poulsbo, United States
    Competing interests
    John Kelly, John Kelly through his employment at VICI Metronic, has a competing interest for the permeation tubes used in the study..
  5. James B Hurley

    Department of Biochemistry, University of Washington, Seattle, United States
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7754-0705
  6. Kenneth P Bube

    Department of Mathematics, University of Washington, Seattle, United States
    Competing interests
    No competing interests declared.
  7. Ian R Sweet

    Department of Medicine, University of Washington, Seattle, United States
    For correspondence
    isweet@uw.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-7565-1663

Funding

National Science Foundation (1853066)

  • Brian M Robbings
  • James B Hurley

National Institute of Diabetes and Digestive and Kidney Diseases (DK17047)

  • Ian R Sweet

National Eye Institute (EY006641)

  • James B Hurley
  • Ian R Sweet

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Ethics

Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (#4091-01) of the University of Washington. All surgery was performed under sodium pentobarbital anesthesia, and every effort was made to minimize suffering.

Reviewing Editor

  1. Michael A Marletta, University of California, Berkeley, United States

Publication history

  1. Received: January 20, 2021
  2. Accepted: November 1, 2021
  3. Accepted Manuscript published: November 4, 2021 (version 1)
  4. Accepted Manuscript updated: November 8, 2021 (version 2)

Copyright

© 2021, Kamat et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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