Open Access
CC BY-NC-ND 4.0 · AJP Rep 2024; 14(02): e162-e169
DOI: 10.1055/a-2318-0625
Original Article

Superoxide Anions Inhibit Intracellular Calcium Response in Porcine Airway Smooth Muscle Cells

1   Department of Pediatrics, University of Tennessee Health Science Center, Memphis, Tennessee
,
Mathur S. Kannan
2   Departments of Pediatrics and Veterinary Pathobiology, University of Minnesota, Minneapolis, Minnesota
,
Deepak A. Deshpande
3   Division of Pulmonary, Allergy and Critical Care Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, Pennsylvania
› Institutsangaben

Funding This study was supported in part by a grant from the Academic Health Center, University of Minnesota and a grant (HL057498) from the National Institutes of Health to Mathur Kannan. None of the other authors has financial relationships to disclose.
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Abstract

Background Superoxide anions (O2 ) have multiple effects on pulmonary parenchyma altering cell proliferation, cellular metabolism, and airway smooth muscle (ASM) contraction. Intracellular calcium ([Ca2+]i) concentration plays a significant role in the regulation of ASM contraction, relaxation, proliferation, and gene expression.

Objective We investigated the effects of O2 on agonist-stimulated changes in [Ca2+]i in ASM cells.

Design/Methods Fura-2 AM-loaded, freshly isolated porcine ASM (PASM) cells were used to examine [Ca2+]i release in response to acetylcholine (ACh), histamine, endothelin, caffeine, and thapsigargin (TPG) in the presence or absence of extracellular Ca2+.

Results Exposure of PASM cells to xanthine and xanthine oxidase (X + XO) resulted in a time-dependent generation of O2 , inhibited by superoxide dismutase (SOD). Preincubating PASM cells with X + XO for 15- or 45-minute inhibited net [Ca2+]i responses to ACh, histamine, caffeine, and TPG compared with control cells. Pretreating PASM cells with SOD for 30 minutes mitigated the inhibitory effect of X + XO treatment on ACh-induced Ca2+ elevation suggesting role of O2 . X + XO treatment also inhibited caffeine- and TPG-induced Ca2+ elevation suggesting effect of O2 on [Ca2+]i release and reuptake mechanisms.

Conclusion Superoxide attenuates [Ca2+]i release, reuptake, and may interfere with physiological functions of ASM cells.

Ethics and Animal Use Approval

The Institutional Animal Care and Use Committees of the University of Minnesota approved the study protocols for the animal care, harvest, and sampling of pig (Sus scrofa) tissues.


Availability of Data and Materials

The authors are willing to share the raw data and details of experimental materials used as per appropriate requests.


Authors' Contribution

R.K. performed experiments, analyzed data, and prepared figures and manuscript. M.K. contributed to study design, data statistical analysis, interpretation, and manuscript writing and editing. D.D. contributed to study methods, data analysis, and manuscript writing and editing.




Publikationsverlauf

Eingereicht: 18. Dezember 2023

Angenommen: 25. April 2024

Accepted Manuscript online:
02. Mai 2024

Artikel online veröffentlicht:
23. Mai 2024

© 2024. The Author(s). This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/)

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