Background

Our protocol focuses on the study of ischemic strokes, specifically on the long-term effects and mechanisms of brain injury following mild ischemic events. Ischemic stroke, particularly acute ischemic stroke (AIS), poses significant challenges for treatment and rehabilitation due to its high prevalence and complexities surrounding timely medical intervention. As traditional treatments, such as intravenous tissue plasminogen activator (tPA), are limited by strict time windows, there is an urgent need for alternative therapeutic strategies that can address the chronic phase of the stroke [1].

Several methodologies have been developed to model ischemic strokes in laboratory settings, with the middle cerebral artery occlusion (MCAO) model being the most widely adopted [2]. MCAO can be executed via the filament method or embolic occlusion, providing a reproducible model of focal ischemia that closely mirrors human stroke patterns. However, MCAO often produces large infarct volumes and can lead to atypical damage, such as hypothalamic injury, which does not commonly occur in human cases. Conversely, the endothelin-1 (ET-1) model facilitates targeted ischemia through localized vasoconstriction, allowing for precise examination of specific regions [3]. Yet, its inability to fully replicate the complex pathophysiological processes of natural strokes presents a limitation.

The photothrombotic model, utilizing a photosensitive dye to induce localized thrombosis via light activation, offers spatial and temporal control over ischemic areas but falls short of mimicking the inflammatory responses associated with strokes [4]. In contrast, our ministroke model involves a combination of permanent distal middle cerebral artery (MCA) ligation and transient bilateral common carotid artery occlusion, resulting in a mild stroke phenotype. This method yields small, consistent lesion volumes and maintains low mortality rates, allowing for the exploration of long-term neuroimmune interactions and other chronic effects of ischemia.

This model presents limitations, such as the requirement for a cranial window and fewer behavioral tests applicable. Despite these limitations, the advantages of our ministroke protocol lie in its ability to produce mild strokes that facilitate the study of chronic pathophysiological processes without the confounding effects of larger infarcts. Unlike models that induce severe injury with high mortality rates, our approach enables researchers to investigate neuroinflammatory responses over extended periods, making it particularly valuable for studying recovery mechanisms and potential therapeutic interventions.

In addition to its primary application in the mechanistic research of ischemic stroke, our protocol can be elegantly adapted for studies focused on therapeutic testing and validation. The ministroke model serves as an invaluable platform for the evaluation of novel neuroprotective agents and rehabilitation strategies. Moreover, the model’s capacity to examine long-term neuroimmune interactions renders it particularly suitable for investigating the role of inflammation in post-stroke recovery. This protocol may also be employed to establish stroke recurrence models. The insights gained from this model could inform strategies to mitigate the long-term consequences of brain injury and improve therapeutic outcomes for stroke patients. Overall, our ministroke model represents a promising tool for advancing the understanding of ischemic stroke and its chronic implications, thereby contributing to the development of effective treatments.