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An in vivo model of ischemic stroke to study potential pharmacological targets

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Resumo:Background: Ischemic Stroke (IS) is caused by a focal disruption in cerebral blood flow due to the occlusion of a blood vessel, most commonly the middle cerebral artery (MCA)—the ischemic cascade results in neuronal death and inflammatory response, including in situ microglia activation. Inflammation is a double‐edged sword; it can cause tissue injury but can also help in the tissue repair of the brain. The only approved pharmacological treatment for IS has strong limitations of use depending on the time post-stroke onset. Despite the efforts to develop neuroprotective agents, none have proven efficacious for the human population. Aim: The aim is to clarify the cerebral cellular behavior during the different phases of ischemia-reperfusion as it might contribute to increasing pharmacological targets toward neuroprotection. Methods: The middle cerebral artery occlusion (MCAO) in vivo model was developed (n=8). Rats were randomly divided into two groups: 1) Animals exposed to 1h of ischemia (I1h) and 2) Animals exposed to 1h of ischemia followed by 1h of reperfusion (I/R1h). Brains were collected and the expression of synaptic markers (PSD-95, Syn), inflammatory mediators (TNF-α, IL-1β, IL-10), markers of microglia (Iba1, iNOS, Arg), and astrocytes (GFAP, S100B) were determined by qRealTime-PCR and Western Blot. Results: We found decreased PSD-95 and Syn expression in the ipsilateral hemisphere of both groups (~0.5 fold-I 1h; ~0.5 fold-I/R 1h), compared to the contralateral hemisphere. Levels of IL-10 were decreased in the ipsilateral hemisphere of both groups (~0.2 fold-I 1h; ~0.4 fold-I/R 1h), compared to the contralateral hemisphere. TNF-α was higher in the I/R 1h group compared to the I 1h group. Iba1 and GFAP expression were reduced in the ipsilateral hemisphere of the I/R 1h group (~0.4 fold and 0.8 fold, respectively). Conclusions: Our results strengthen the MCAO rodent model as a potential model to study neuroinflammation as a pharmacological target. Further research is needed to clarify time-dependent changes.
Autores principais:Mendes, Priscila
Outros Autores:Solas, João; Santos, Sofia; Fernandes, Adelaide; Ratilal, Bernardo; Mateus, Vanessa; Rocha, João
Assunto:Ischemia Neuroinflammation Reperfusion Stroke IPL/2022/MCAO_ESTeSL UIDB/05608/2020 UIDP/05608/2020
Ano:2023
País:Portugal
Tipo de documento:documento de conferência
Tipo de acesso:acesso aberto
Instituição associada:Instituto Politécnico de Lisboa
Idioma:inglês
Origem:Repositório Científico do Instituto Politécnico de Lisboa
Descrição
Resumo:Background: Ischemic Stroke (IS) is caused by a focal disruption in cerebral blood flow due to the occlusion of a blood vessel, most commonly the middle cerebral artery (MCA)—the ischemic cascade results in neuronal death and inflammatory response, including in situ microglia activation. Inflammation is a double‐edged sword; it can cause tissue injury but can also help in the tissue repair of the brain. The only approved pharmacological treatment for IS has strong limitations of use depending on the time post-stroke onset. Despite the efforts to develop neuroprotective agents, none have proven efficacious for the human population. Aim: The aim is to clarify the cerebral cellular behavior during the different phases of ischemia-reperfusion as it might contribute to increasing pharmacological targets toward neuroprotection. Methods: The middle cerebral artery occlusion (MCAO) in vivo model was developed (n=8). Rats were randomly divided into two groups: 1) Animals exposed to 1h of ischemia (I1h) and 2) Animals exposed to 1h of ischemia followed by 1h of reperfusion (I/R1h). Brains were collected and the expression of synaptic markers (PSD-95, Syn), inflammatory mediators (TNF-α, IL-1β, IL-10), markers of microglia (Iba1, iNOS, Arg), and astrocytes (GFAP, S100B) were determined by qRealTime-PCR and Western Blot. Results: We found decreased PSD-95 and Syn expression in the ipsilateral hemisphere of both groups (~0.5 fold-I 1h; ~0.5 fold-I/R 1h), compared to the contralateral hemisphere. Levels of IL-10 were decreased in the ipsilateral hemisphere of both groups (~0.2 fold-I 1h; ~0.4 fold-I/R 1h), compared to the contralateral hemisphere. TNF-α was higher in the I/R 1h group compared to the I 1h group. Iba1 and GFAP expression were reduced in the ipsilateral hemisphere of the I/R 1h group (~0.4 fold and 0.8 fold, respectively). Conclusions: Our results strengthen the MCAO rodent model as a potential model to study neuroinflammation as a pharmacological target. Further research is needed to clarify time-dependent changes.