Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy
Autor(a) principal: | |
---|---|
Data de Publicação: | 2007 |
Outros Autores: | , , , , , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
Texto Completo: | http://hdl.handle.net/10316/12733 https://doi.org/10.1167/iovs.07-0112 |
Resumo: | PURPOSE: Nitric oxide (NO) is involved in leukostasis and blood-retinal barrier (BRB) breakdown in the early stages of diabetic retinopathy (DR), but it is unclear which NO synthase (NOS) isoforms are primarily involved. In this study, the authors aimed to clarify the involvement of constitutive (eNOS, nNOS) and inducible NOS (iNOS) isoforms and the mechanisms underlying NO-mediated leukostasis and BRB breakdown. METHODS: Diabetes was induced with streptozotocin for 2 weeks. Mice were treated with a NOS inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), which shows a preference for constitutive isoforms over iNOS. Vessel leakage was assessed with Evans blue. Leukostasis was quantified in flat-mounted retinas with confocal microscopy, in vivo with a scanning laser ophthalmoscope, and in vitro in a retinal endothelial cell line. ICAM-1, occludin, and ZO-1 levels were assessed by Western blot, flow cytometry, or immunohistochemistry. Nitrotyrosine content was assessed by immunohistochemistry. RESULTS: Diabetes increased leukostasis within retinal vessels and BRB permeability, which were reduced by L-NAME. Similar effects were observed in diabetic iNOS knockout mice. In diabetic mouse retinas, ICAM-1 protein levels increased, whereas the immunoreactivity of tight junction proteins, occludin and ZO-1 decreased, in correlation with increased protein levels of all NOS isoforms. Those effects were prevented by L-NAME and also in diabetic iNOS knockout mice. High glucose and nitrosative/oxidative stress also increased leukostasis caused by ICAM-1 upregulation. CONCLUSIONS: These results indicate that the iNOS isoform plays a predominant role in leukostasis and BRB breakdown. The mechanism involves ICAM-1 upregulation and tight junction protein downregulation |
id |
RCAP_0b9b0d6758570c42f35cf88b97bb5848 |
---|---|
oai_identifier_str |
oai:estudogeral.uc.pt:10316/12733 |
network_acronym_str |
RCAP |
network_name_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository_id_str |
7160 |
spelling |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathyPURPOSE: Nitric oxide (NO) is involved in leukostasis and blood-retinal barrier (BRB) breakdown in the early stages of diabetic retinopathy (DR), but it is unclear which NO synthase (NOS) isoforms are primarily involved. In this study, the authors aimed to clarify the involvement of constitutive (eNOS, nNOS) and inducible NOS (iNOS) isoforms and the mechanisms underlying NO-mediated leukostasis and BRB breakdown. METHODS: Diabetes was induced with streptozotocin for 2 weeks. Mice were treated with a NOS inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), which shows a preference for constitutive isoforms over iNOS. Vessel leakage was assessed with Evans blue. Leukostasis was quantified in flat-mounted retinas with confocal microscopy, in vivo with a scanning laser ophthalmoscope, and in vitro in a retinal endothelial cell line. ICAM-1, occludin, and ZO-1 levels were assessed by Western blot, flow cytometry, or immunohistochemistry. Nitrotyrosine content was assessed by immunohistochemistry. RESULTS: Diabetes increased leukostasis within retinal vessels and BRB permeability, which were reduced by L-NAME. Similar effects were observed in diabetic iNOS knockout mice. In diabetic mouse retinas, ICAM-1 protein levels increased, whereas the immunoreactivity of tight junction proteins, occludin and ZO-1 decreased, in correlation with increased protein levels of all NOS isoforms. Those effects were prevented by L-NAME and also in diabetic iNOS knockout mice. High glucose and nitrosative/oxidative stress also increased leukostasis caused by ICAM-1 upregulation. CONCLUSIONS: These results indicate that the iNOS isoform plays a predominant role in leukostasis and BRB breakdown. The mechanism involves ICAM-1 upregulation and tight junction protein downregulationFoundation for Science and Technology, Portugal (Grant POCTI/CB/38545/01)FEDERAssociation for Research in Vision and Ophthalmology2007-11info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/articlehttp://hdl.handle.net/10316/12733http://hdl.handle.net/10316/12733https://doi.org/10.1167/iovs.07-0112engInvestigative Ophthalmology & Visual Science. 48:11 (2007) 5257-52650146-0404Leal, Ermelindo C.Manivannan, AyyakkannuHosoya, Ken-IchiTerasaki, TetsuyaCunha-Vaz, JoséAmbrósio, António FranciscoForrester, John V.info:eu-repo/semantics/openAccessreponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãoinstacron:RCAAP2022-05-25T04:05:04Zoai:estudogeral.uc.pt:10316/12733Portal AgregadorONGhttps://www.rcaap.pt/oai/openaireopendoar:71602024-03-19T20:43:37.902037Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informaçãofalse |
dc.title.none.fl_str_mv |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
title |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
spellingShingle |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy Leal, Ermelindo C. |
title_short |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
title_full |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
title_fullStr |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
title_full_unstemmed |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
title_sort |
Inducible nitric oxide synthase isoform is a key mediator of leukostasis and blood-retinal barrier breakdown in diabetic retinopathy |
author |
Leal, Ermelindo C. |
author_facet |
Leal, Ermelindo C. Manivannan, Ayyakkannu Hosoya, Ken-Ichi Terasaki, Tetsuya Cunha-Vaz, José Ambrósio, António Francisco Forrester, John V. |
author_role |
author |
author2 |
Manivannan, Ayyakkannu Hosoya, Ken-Ichi Terasaki, Tetsuya Cunha-Vaz, José Ambrósio, António Francisco Forrester, John V. |
author2_role |
author author author author author author |
dc.contributor.author.fl_str_mv |
Leal, Ermelindo C. Manivannan, Ayyakkannu Hosoya, Ken-Ichi Terasaki, Tetsuya Cunha-Vaz, José Ambrósio, António Francisco Forrester, John V. |
description |
PURPOSE: Nitric oxide (NO) is involved in leukostasis and blood-retinal barrier (BRB) breakdown in the early stages of diabetic retinopathy (DR), but it is unclear which NO synthase (NOS) isoforms are primarily involved. In this study, the authors aimed to clarify the involvement of constitutive (eNOS, nNOS) and inducible NOS (iNOS) isoforms and the mechanisms underlying NO-mediated leukostasis and BRB breakdown. METHODS: Diabetes was induced with streptozotocin for 2 weeks. Mice were treated with a NOS inhibitor, N(G)-nitro-L-arginine methyl ester (L-NAME), which shows a preference for constitutive isoforms over iNOS. Vessel leakage was assessed with Evans blue. Leukostasis was quantified in flat-mounted retinas with confocal microscopy, in vivo with a scanning laser ophthalmoscope, and in vitro in a retinal endothelial cell line. ICAM-1, occludin, and ZO-1 levels were assessed by Western blot, flow cytometry, or immunohistochemistry. Nitrotyrosine content was assessed by immunohistochemistry. RESULTS: Diabetes increased leukostasis within retinal vessels and BRB permeability, which were reduced by L-NAME. Similar effects were observed in diabetic iNOS knockout mice. In diabetic mouse retinas, ICAM-1 protein levels increased, whereas the immunoreactivity of tight junction proteins, occludin and ZO-1 decreased, in correlation with increased protein levels of all NOS isoforms. Those effects were prevented by L-NAME and also in diabetic iNOS knockout mice. High glucose and nitrosative/oxidative stress also increased leukostasis caused by ICAM-1 upregulation. CONCLUSIONS: These results indicate that the iNOS isoform plays a predominant role in leukostasis and BRB breakdown. The mechanism involves ICAM-1 upregulation and tight junction protein downregulation |
publishDate |
2007 |
dc.date.none.fl_str_mv |
2007-11 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://hdl.handle.net/10316/12733 http://hdl.handle.net/10316/12733 https://doi.org/10.1167/iovs.07-0112 |
url |
http://hdl.handle.net/10316/12733 https://doi.org/10.1167/iovs.07-0112 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
Investigative Ophthalmology & Visual Science. 48:11 (2007) 5257-5265 0146-0404 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.publisher.none.fl_str_mv |
Association for Research in Vision and Ophthalmology |
publisher.none.fl_str_mv |
Association for Research in Vision and Ophthalmology |
dc.source.none.fl_str_mv |
reponame:Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) instname:Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação instacron:RCAAP |
instname_str |
Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
instacron_str |
RCAAP |
institution |
RCAAP |
reponame_str |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
collection |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) |
repository.name.fl_str_mv |
Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos) - Agência para a Sociedade do Conhecimento (UMIC) - FCT - Sociedade da Informação |
repository.mail.fl_str_mv |
|
_version_ |
1799133708496666624 |