Examining the protective effects of sesamol on oxidative stress associated blood -brain barrier dysfunction in streptozotocin-induced diabetic rats

Hemoglobin (Hb) released from extravasated erythrocytes is implicated in brain edema after intracerebral hemorrhage (ICH). Hemoglobin is a major component of blood and a potent mediator of oxidative stress after ICH. Oxidative stress and matrix metalloproteinases (MMPs) are associated with blood–brain barrier (BBB) dysfunction. This study was designed to elucidate whether Hb-induced oxidative stress contributes to MMP-9 activation and BBB dysfunction in vivo. An intracerebral injection of Hb into rat striata induced increased hydroethidine (HEt) signals in parallel with MMP-9 levels. In situ gelatinolytic activity colocalized with oxidized HEt signals in vessel walls, accompanied by immunoglobulin G leakage and a decrease in immunoactivity of endothelial barrier antigen, a marker of endothelial integrity. Administration of a nonselective MMP inhibitor prevented MMP-9 levels and albumin leakage in injured striata. Moreover, reduction in oxidative stress by copper/zinc-superoxide dismutase (SOD1) overexpression reduced oxidative stress, MMP-9 levels, albumin leakage, and subsequent apoptosis compared with wild-type littermates. We speculate that Hb-induced oxidative stress may contribute to early BBB dysfunction and subsequent apoptosis, partly through MMP activation, and that SOD1 overexpression may reduce Hb-induced oxidative stress, BBB dysfunction, and apoptotic cell death.

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Blood-brain barrier dysfunction in hemorrhagic transformation: a therapeutic opportunity for nanoparticles and melatonin.

Journal of Neurophysiology ◽

10.1152/jn.00638.2020 ◽

2021 ◽

Author(s):

Esteban Figueroa ◽

Alejandro González-Candia ◽

Aitor Caballero-Román ◽

Cristina Fornaguera ◽

Elvira Escribano-Ferrer ◽

...

Keyword(s):

Oxidative Stress ◽

Ischemic Stroke ◽

Blood Brain Barrier ◽

Medical Condition ◽

Brain Area ◽

Hemorrhagic Transformation ◽

Brain Barrier ◽

World Population ◽

Barrier Dysfunction ◽

Blood Brain

Stroke is the second leading cause of death worldwide, estimated that 1/6 of the world population will suffer it once in their life. The most common type of this medical condition is the ischemic stroke (IS), produced by a thrombotic or embolic occlusion of a major cerebral artery or its branches, leading to the formation of a complex infarct region caused by oxidative stress, excitotoxicity and endothelial dysfunction. Nowadays, the immediate treatment for IS involves thrombolytic agents or mechanical thrombectomy, depending on the integrity of the blood-brain barrier (BBB). A common stroke complication is the hemorrhagic transformation (HT), which consists of bleeding into the ischemic brain area. Currently, better treatments for IS are urgently needed. As such, the neurohormone melatonin has been proposed as a good candidate due to its antioxidant, anti-inflammatory and neuroprotective effects, particularly against lipid peroxidation and oxidative stress during brain ischemia. Here, we proposed to develop intravenous or intranasal melatonin nanoformulation to specifically target the brain in stroke patients. Nowadays, the challenge is to find a formulation able to cross the barriers and reach the target organ in an effective dose to generate the pharmacological effect. In this review, we discuss the current literature about stroke pathophysiology, melatonin properties and its potential use in nanoformulations as a novel therapeutic approach for ischemic stroke.

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CORM-A1 prevents blood-brain barrier dysfunction caused by ionotropic glutamate receptor-mediated endothelial oxidative stress and apoptosis

AJP Cell Physiology ◽

10.1152/ajpcell.00023.2013 ◽

2013 ◽

Vol 304 (11) ◽

pp. C1105-C1115 ◽

Cited By ~ 30

Author(s):

Shyamali Basuroy ◽

Charles W. Leffler ◽

Helena Parfenova

Keyword(s):

Oxidative Stress ◽

Blood Brain Barrier ◽

Antioxidant Properties ◽

Brain Barrier ◽

Glutamate Excitotoxicity ◽

Ros Production ◽

Barrier Dysfunction ◽

Semipermeable Membranes ◽

Endothelial Apoptosis ◽

Blood Brain

In cerebral microvascular endothelial cells (CMVEC) of newborn pigs, glutamate at excitotoxic concentrations (mM) causes apoptosis mediated by reactive oxygen species (ROS). Carbon monoxide (CO) produced by CMVEC or delivered by a CO-releasing molecule, CORM-A1, has antioxidant properties. We tested the hypothesis that CORM-A1 prevents cerebrovascular endothelial barrier dysfunction caused by glutamate excitotoxicity. First, we identified the glutamate receptors (GluRs) and enzymatic sources of ROS involved in the mechanism of endothelial apoptosis. In glutamate-exposed CMVEC, ROS formation and apoptosis were blocked by rotenone, 2-thenoyltrifluoroacetone (TTFA), and antimycin, indicating that mitochondrial complexes I, II, and III are the major sources of oxidative stress. Agonists of ionotropic GluRs (iGluRs) N-methyl-D-aspartate (NMDA), cis-ACPD, AMPA, and kainate increased ROS production and apoptosis, whereas iGluR antagonists exhibited antiapoptotic properties, suggesting that iGluRs mediate glutamate-induced endothelial apoptosis. The functional consequences of endothelial injury were tested in the model of blood-brain barrier (BBB) composed of CMVEC monolayer on semipermeable membranes. Glutamate and iGluR agonists reduced transendothelial electrical resistance and increased endothelial paracellular permeability to 3-kDa dextran. CORM-A1 exhibited potent antioxidant and antiapoptotic properties in CMVEC and completely prevented BBB dysfunction caused by glutamate and iGluR agonists. Overall, the endothelial component of the BBB is a cellular target for excitotoxic glutamate that, via a mechanism involving a iGluR-mediated activation of mitochondrial ROS production and apoptosis, leads to BBB opening that may be prevented by the antioxidant and antiapoptotic actions of CORMs. Antioxidant CORMs therapy may help preserve BBB functional integrity in neonatal cerebrovascular disease.

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