Cargando…

Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins

Pneumonia is a leading cause of death in children and the elderly worldwide, accounting for 15% of all deaths of children under 5 years old. Streptococcus pneumoniae is a common and aggressive cause of pneumonia and can also contribute to meningitis and sepsis. Despite the widespread use of antibiot...

Descripción completa

Detalles Bibliográficos
Autores principales: Li, Xueyi, Yu, Yanfang, Gorshkov, Boris, Haigh, Stephen, Bordan, Zsuzsanna, Weintraub, Daniel, Rudic, Radu Daniel, Chakraborty, Trinad, Barman, Scott A., Verin, Alexander D., Su, Yunchao, Lucas, Rudolf, Stepp, David W., Chen, Feng, Fulton, David J. R.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2018
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6008539/
https://www.ncbi.nlm.nih.gov/pubmed/29951058
http://dx.doi.org/10.3389/fimmu.2018.01309
_version_ 1783333197883375616
author Li, Xueyi
Yu, Yanfang
Gorshkov, Boris
Haigh, Stephen
Bordan, Zsuzsanna
Weintraub, Daniel
Rudic, Radu Daniel
Chakraborty, Trinad
Barman, Scott A.
Verin, Alexander D.
Su, Yunchao
Lucas, Rudolf
Stepp, David W.
Chen, Feng
Fulton, David J. R.
author_facet Li, Xueyi
Yu, Yanfang
Gorshkov, Boris
Haigh, Stephen
Bordan, Zsuzsanna
Weintraub, Daniel
Rudic, Radu Daniel
Chakraborty, Trinad
Barman, Scott A.
Verin, Alexander D.
Su, Yunchao
Lucas, Rudolf
Stepp, David W.
Chen, Feng
Fulton, David J. R.
author_sort Li, Xueyi
collection PubMed
description Pneumonia is a leading cause of death in children and the elderly worldwide, accounting for 15% of all deaths of children under 5 years old. Streptococcus pneumoniae is a common and aggressive cause of pneumonia and can also contribute to meningitis and sepsis. Despite the widespread use of antibiotics, mortality rates for pneumonia remain unacceptably high in part due to the release of bacterial toxins. Pneumolysin (PLY) is a cholesterol-dependent toxin that is produced by Streptococcus, and it is both necessary and sufficient for the development of the extensive pulmonary permeability edema that underlies acute lung injury. The mechanisms by which PLY disrupts the pulmonary endothelial barrier are not fully understood. Previously, we found that reactive oxygen species (ROS) contribute to the barrier destructive effects of PLY and identified an unexpected but potent role of Hsp70 in suppressing ROS production. The ability of Hsp70 to influence PLY-induced barrier dysfunction is not yet described, and the goal of the current study was to identify whether Hsp70 upregulation is an effective strategy to protect the lung microvascular endothelial barrier from G(+) bacterial toxins. Overexpression of Hsp70 via adenovirus-mediated gene transfer attenuated PLY-induced increases in permeability in human lung microvascular endothelial cells (HLMVEC) with no evidence of cytotoxicity. To adopt a more translational approach, we employed a pharmacological approach using geranylgeranylacetone (GGA) to acutely upregulate endogenous Hsp70 expression. Following acute treatment (6 h) with GGA, HLMVECs exposed to PLY displayed improved cell viability and enhanced endothelial barrier function as measured by both Electric Cell-substrate Impedance Sensing (ECIS) and transwell permeability assays compared to control treated cells. PLY promoted increased mitochondrial ROS, decreased mitochondrial oxygen consumption, and increased caspase 3 cleavage and cell death, which were collectively improved in cells pretreated with GGA. In mice, IP pretreatment with GGA 24 h prior to IT administration of PLY resulted in significantly less Evans Blue Dye extravasation compared to vehicle, indicating preserved endothelial barrier integrity and suggesting that the acute upregulation of Hsp70 may be an effective therapeutic approach in the treatment of lung injury associated with pneumonia.
format Online
Article
Text
id pubmed-6008539
institution National Center for Biotechnology Information
language English
publishDate 2018
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-60085392018-06-27 Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins Li, Xueyi Yu, Yanfang Gorshkov, Boris Haigh, Stephen Bordan, Zsuzsanna Weintraub, Daniel Rudic, Radu Daniel Chakraborty, Trinad Barman, Scott A. Verin, Alexander D. Su, Yunchao Lucas, Rudolf Stepp, David W. Chen, Feng Fulton, David J. R. Front Immunol Immunology Pneumonia is a leading cause of death in children and the elderly worldwide, accounting for 15% of all deaths of children under 5 years old. Streptococcus pneumoniae is a common and aggressive cause of pneumonia and can also contribute to meningitis and sepsis. Despite the widespread use of antibiotics, mortality rates for pneumonia remain unacceptably high in part due to the release of bacterial toxins. Pneumolysin (PLY) is a cholesterol-dependent toxin that is produced by Streptococcus, and it is both necessary and sufficient for the development of the extensive pulmonary permeability edema that underlies acute lung injury. The mechanisms by which PLY disrupts the pulmonary endothelial barrier are not fully understood. Previously, we found that reactive oxygen species (ROS) contribute to the barrier destructive effects of PLY and identified an unexpected but potent role of Hsp70 in suppressing ROS production. The ability of Hsp70 to influence PLY-induced barrier dysfunction is not yet described, and the goal of the current study was to identify whether Hsp70 upregulation is an effective strategy to protect the lung microvascular endothelial barrier from G(+) bacterial toxins. Overexpression of Hsp70 via adenovirus-mediated gene transfer attenuated PLY-induced increases in permeability in human lung microvascular endothelial cells (HLMVEC) with no evidence of cytotoxicity. To adopt a more translational approach, we employed a pharmacological approach using geranylgeranylacetone (GGA) to acutely upregulate endogenous Hsp70 expression. Following acute treatment (6 h) with GGA, HLMVECs exposed to PLY displayed improved cell viability and enhanced endothelial barrier function as measured by both Electric Cell-substrate Impedance Sensing (ECIS) and transwell permeability assays compared to control treated cells. PLY promoted increased mitochondrial ROS, decreased mitochondrial oxygen consumption, and increased caspase 3 cleavage and cell death, which were collectively improved in cells pretreated with GGA. In mice, IP pretreatment with GGA 24 h prior to IT administration of PLY resulted in significantly less Evans Blue Dye extravasation compared to vehicle, indicating preserved endothelial barrier integrity and suggesting that the acute upregulation of Hsp70 may be an effective therapeutic approach in the treatment of lung injury associated with pneumonia. Frontiers Media S.A. 2018-06-12 /pmc/articles/PMC6008539/ /pubmed/29951058 http://dx.doi.org/10.3389/fimmu.2018.01309 Text en Copyright © 2018 Li, Yu, Gorshkov, Haigh, Bordan, Weintraub, Rudic, Chakraborty, Barman, Verin, Su, Lucas, Stepp, Chen and Fulton. https://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Immunology
Li, Xueyi
Yu, Yanfang
Gorshkov, Boris
Haigh, Stephen
Bordan, Zsuzsanna
Weintraub, Daniel
Rudic, Radu Daniel
Chakraborty, Trinad
Barman, Scott A.
Verin, Alexander D.
Su, Yunchao
Lucas, Rudolf
Stepp, David W.
Chen, Feng
Fulton, David J. R.
Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title_full Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title_fullStr Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title_full_unstemmed Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title_short Hsp70 Suppresses Mitochondrial Reactive Oxygen Species and Preserves Pulmonary Microvascular Barrier Integrity Following Exposure to Bacterial Toxins
title_sort hsp70 suppresses mitochondrial reactive oxygen species and preserves pulmonary microvascular barrier integrity following exposure to bacterial toxins
topic Immunology
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6008539/
https://www.ncbi.nlm.nih.gov/pubmed/29951058
http://dx.doi.org/10.3389/fimmu.2018.01309
work_keys_str_mv AT lixueyi hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT yuyanfang hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT gorshkovboris hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT haighstephen hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT bordanzsuzsanna hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT weintraubdaniel hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT rudicradudaniel hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT chakrabortytrinad hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT barmanscotta hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT verinalexanderd hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT suyunchao hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT lucasrudolf hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT steppdavidw hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT chenfeng hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins
AT fultondavidjr hsp70suppressesmitochondrialreactiveoxygenspeciesandpreservespulmonarymicrovascularbarrierintegrityfollowingexposuretobacterialtoxins