Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model

<i>Background and Objectives:</i> Ocular alkaline burn is a clinical emergency that can cause permanent vision loss due to limbal stem cell deficiency and corneal neovascularization (CNV). Although the basic pathogenetic mechanisms are considered to be acute oxidative stress and corneal...

Full description

Bibliographic Details
Main Authors: Gokhan Ozge, Umut Karaca, Mehtap Savran, Gulsah Usta, Kanat Gulle, Murat Sevimli, Fatma Nihan Cankara, Halil Asci
Format: Article
Language:English
Published: MDPI AG 2023-02-01
Series:Medicina
Subjects:
Online Access:https://www.mdpi.com/1648-9144/59/2/323
_version_ 1797619487629901824
author Gokhan Ozge
Umut Karaca
Mehtap Savran
Gulsah Usta
Kanat Gulle
Murat Sevimli
Fatma Nihan Cankara
Halil Asci
author_facet Gokhan Ozge
Umut Karaca
Mehtap Savran
Gulsah Usta
Kanat Gulle
Murat Sevimli
Fatma Nihan Cankara
Halil Asci
author_sort Gokhan Ozge
collection DOAJ
description <i>Background and Objectives:</i> Ocular alkaline burn is a clinical emergency that can cause permanent vision loss due to limbal stem cell deficiency and corneal neovascularization (CNV). Although the basic pathogenetic mechanisms are considered to be acute oxidative stress and corneal neovascularization triggered by inflammation, the underlying intracellular mechanisms have not been clearly elucidated. The aim of this study was to investigate the role of endoplasmic reticulum (ER) stress on inflammation and neovascularization, and the effect of the ER stress inhibitor salubrinal (SLB), as a novel treatment in a corneal alkaline burn model in rats. <i>Methods:</i> Chemical burns were created by cautery for 4 s using a rod coated with 75% silver nitrate and 25% potassium nitrate in the corneal center for the corneal neovascularization (CNV) model. Twenty-eight Wistar albino rats were divided into four groups: SHAM, CNV, CNV + SLB, and CNV + bevacizumab (BVC). After the CNV model was applied to the right eye, a single subconjunctival dose (0.05 mL) of 1 mg/kg salubrinal was injected into both eyes in the CNV + SLB group. A total of 1.25 mg/mL of subconjunctival BVC was administered to the CNV + BVC group. Fourteen days after experimental modeling and drug administration, half of the globes were placed in liquid nitrogen and stored at −20 °C until biochemical analysis. The remaining tissues were collected and fixed in 10% buffered formalin for histopathological and immunohistochemical analysis. Three qualitative agents from three different pathways were chosen: TNFR for inflammation, endothelial nitric oxide synthase (e-NOS) for vascular endothelial growth factor (VEGF)-mediated vascular permeability, and caspase-3 for cellular apoptosis. <i>Results:</i> Significantly lower caspase-3 and eNOS levels were detected in the CNV + SLB and CNV + BVC groups than in the CNV group. Additionally, histopathological evaluation revealed a significant decrease in neovascularization, inflammatory cell infiltration, and fibroblast activity in the CNV + SLB and CNV + BVC groups. The endoplasmic reticulum stress inhibitor, salubrinal, administered to the treatment group, attenuated apoptosis (caspase-3) and inflammation (e-NOS). In the control group (left eyes of the SLB group), salubrinal did not have a toxic effect on the healthy corneas. <i>Conclusion:</i> The ER stress pathway plays an important role in angiogenesis after alkaline corneal burns, and treatment with SLB modulates this pathway, reducing caspase-3 and eNOS levels. Further studies are needed to understand the molecular mechanisms altered by SLB-mediated therapy. The fact that more than one mechanism plays a role in the pathogenesis of CNV may require the use of more than one molecule in treatment. SLB has the potential to affect multiple steps in CNV pathogenesis, both in terms of reducing ER stress and regulating cellular homeostasis by inhibiting the core event of integrated stress response (ISR). Therefore, it can be used as a new treatment option and as a strengthening agent for existing treatments. Although blockade of intracellular organelle stress pathways has shown promising results in experimental studies, more in-depth research is needed before it can be used in routine practice. To the best of our knowledge, this study is the first to report the role of ER stress in corneal injury.
first_indexed 2024-03-11T08:27:46Z
format Article
id doaj.art-c945c1ab7cd049ee8af9238c4967c339
institution Directory Open Access Journal
issn 1010-660X
1648-9144
language English
last_indexed 2024-03-11T08:27:46Z
publishDate 2023-02-01
publisher MDPI AG
record_format Article
series Medicina
spelling doaj.art-c945c1ab7cd049ee8af9238c4967c3392023-11-16T22:00:12ZengMDPI AGMedicina1010-660X1648-91442023-02-0159232310.3390/medicina59020323Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization ModelGokhan Ozge0Umut Karaca1Mehtap Savran2Gulsah Usta3Kanat Gulle4Murat Sevimli5Fatma Nihan Cankara6Halil Asci7Department of Ophthalmology, Gulhane Faculty of Medicine, University of Health Sciences, 06018 Ankara, TurkeyDepartment of Ophthalmology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Pharmacology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Ophthalmology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Histology and Embryology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Histology and Embryology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Pharmacology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, TurkeyDepartment of Pharmacology, Faculty of Medicine, Suleyman Demirel University, 32260 Isparta, Turkey<i>Background and Objectives:</i> Ocular alkaline burn is a clinical emergency that can cause permanent vision loss due to limbal stem cell deficiency and corneal neovascularization (CNV). Although the basic pathogenetic mechanisms are considered to be acute oxidative stress and corneal neovascularization triggered by inflammation, the underlying intracellular mechanisms have not been clearly elucidated. The aim of this study was to investigate the role of endoplasmic reticulum (ER) stress on inflammation and neovascularization, and the effect of the ER stress inhibitor salubrinal (SLB), as a novel treatment in a corneal alkaline burn model in rats. <i>Methods:</i> Chemical burns were created by cautery for 4 s using a rod coated with 75% silver nitrate and 25% potassium nitrate in the corneal center for the corneal neovascularization (CNV) model. Twenty-eight Wistar albino rats were divided into four groups: SHAM, CNV, CNV + SLB, and CNV + bevacizumab (BVC). After the CNV model was applied to the right eye, a single subconjunctival dose (0.05 mL) of 1 mg/kg salubrinal was injected into both eyes in the CNV + SLB group. A total of 1.25 mg/mL of subconjunctival BVC was administered to the CNV + BVC group. Fourteen days after experimental modeling and drug administration, half of the globes were placed in liquid nitrogen and stored at −20 °C until biochemical analysis. The remaining tissues were collected and fixed in 10% buffered formalin for histopathological and immunohistochemical analysis. Three qualitative agents from three different pathways were chosen: TNFR for inflammation, endothelial nitric oxide synthase (e-NOS) for vascular endothelial growth factor (VEGF)-mediated vascular permeability, and caspase-3 for cellular apoptosis. <i>Results:</i> Significantly lower caspase-3 and eNOS levels were detected in the CNV + SLB and CNV + BVC groups than in the CNV group. Additionally, histopathological evaluation revealed a significant decrease in neovascularization, inflammatory cell infiltration, and fibroblast activity in the CNV + SLB and CNV + BVC groups. The endoplasmic reticulum stress inhibitor, salubrinal, administered to the treatment group, attenuated apoptosis (caspase-3) and inflammation (e-NOS). In the control group (left eyes of the SLB group), salubrinal did not have a toxic effect on the healthy corneas. <i>Conclusion:</i> The ER stress pathway plays an important role in angiogenesis after alkaline corneal burns, and treatment with SLB modulates this pathway, reducing caspase-3 and eNOS levels. Further studies are needed to understand the molecular mechanisms altered by SLB-mediated therapy. The fact that more than one mechanism plays a role in the pathogenesis of CNV may require the use of more than one molecule in treatment. SLB has the potential to affect multiple steps in CNV pathogenesis, both in terms of reducing ER stress and regulating cellular homeostasis by inhibiting the core event of integrated stress response (ISR). Therefore, it can be used as a new treatment option and as a strengthening agent for existing treatments. Although blockade of intracellular organelle stress pathways has shown promising results in experimental studies, more in-depth research is needed before it can be used in routine practice. To the best of our knowledge, this study is the first to report the role of ER stress in corneal injury.https://www.mdpi.com/1648-9144/59/2/323apoptosiscorneal injuryinflammationendoplasmic reticulum stresseNOS
spellingShingle Gokhan Ozge
Umut Karaca
Mehtap Savran
Gulsah Usta
Kanat Gulle
Murat Sevimli
Fatma Nihan Cankara
Halil Asci
Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
Medicina
apoptosis
corneal injury
inflammation
endoplasmic reticulum stress
eNOS
title Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
title_full Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
title_fullStr Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
title_full_unstemmed Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
title_short Salubrinal Ameliorates Inflammation and Neovascularization via the Caspase 3/Enos Signaling in an Alkaline-Induced Rat Corneal Neovascularization Model
title_sort salubrinal ameliorates inflammation and neovascularization via the caspase 3 enos signaling in an alkaline induced rat corneal neovascularization model
topic apoptosis
corneal injury
inflammation
endoplasmic reticulum stress
eNOS
url https://www.mdpi.com/1648-9144/59/2/323
work_keys_str_mv AT gokhanozge salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT umutkaraca salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT mehtapsavran salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT gulsahusta salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT kanatgulle salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT muratsevimli salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT fatmanihancankara salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel
AT halilasci salubrinalamelioratesinflammationandneovascularizationviathecaspase3enossignalinginanalkalineinducedratcornealneovascularizationmodel