Proteomic Characterization of the Dynamics of Ischemic Stroke in Mice

Abstract

Novel therapies and biomarkers are needed for the treatment of acute ischemic stroke (AIS). This study aimed to provide comprehensive insights into the dynamic proteome changes and underlying molecular mechanisms post-ischemic stroke. TMT-coupled proteomic analysis was conducted on mouse brain cortex tissue from five time points up to 4 weeks poststroke in the distal hypoxic-middle cerebral artery occlusion (DH-MCAO) model. We found that nearly half of the detected proteome was altered following stroke, but only ∼8.6% of the changes were at relatively large scales. Clustering on the changed proteome defined four distinct expression patterns characterized by temporal and quantitative changes in innate and adaptive immune response pathways and cytoskeletal and neuronal remodeling. Further analysis on a subset of 309 “top hits”, which temporally responded to stroke with relatively large and sustained changes, revealed that they were mostly secreted proteins, highly correlated to different cortical cytokines, and thereby potential pharmacodynamic biomarker candidates for inflammation-targeting therapies. Closer examination of the top enriched neurophysiologic pathways identified 57 proteins potentially associated with poststroke recovery. Altogether, our study generated a rich dataset with candidate proteins worthy of further validation as biomarkers and/or therapeutic targets for stroke. The proteomics data are available in the PRIDE Archive with identifier PXD025077.

Complement C3a treatment accelerates recovery after stroke via modulation of astrocyte reactivity and cortical connectivity

“…C1q mRNA is highly expressed by reactive microglia ( 52 ), and microglial C1q is a major regulator of astrocyte functions ( 10 , 53 , 54 ). Our results support previous findings of increased C1q protein levels in the ipsilesional cortex after ischemic stroke ( 55 ) and show that C1q does not act as a mediator of the effects of C3a treatment in the post-stroke brain. Clec7a is a marker of disease-associated microglia with increased phagocytic activity and the potential to restrict neurodegeneration ( 35 , 56 ).…”

ERK1/2 Activity Is Critical for the Outcome of Ischemic Stroke

“…To evaluate the function of the regulated proteins in the ipsilateral hemisphere and their impact on stroke outcome, we assigned the significantly regulated proteins to gene ontology functional categories (GO-term: biological process) using a cut-off for a 2-fold upregulation and for a 0.5-fold downregulation compared to wt bgi. These results show that the regulated proteins were found within the signaling processes commonly involved after ischemic brain injury, such as cell proliferation, cell differentiation, cell growth, cell death, translation, transcription, synaptic plasticity, signal transduction, metabolism, protein transport, vesicle transport, proteolysis, cell adhesion, membrane potential, immune response/inflammation, cytoskeleton organization, and regulation of hydrogen peroxide ( Tables S6–S8 ) [ 33 , 34 , 35 ]. As these processes were affected in all genotypes, the analyses did not allow the identification of a main mechanism for the respective genotypes.…”

Proteomic investigations of acute ischemic stroke in animal models: a narrative review

“…[43] The dysregulated proteins identified poststroke at multiple time intervals largely overlapped across several studies despite use of different AIS animal models. For example, 604 dysregulated proteins overlapped between the aforementioned rat MCAO [41] and our mouse DH-MCAO [42] studies, and over 72% of these proteins changed in the same direction. The cytoskeleton and synaptic remodeling, the adaptive immune response, and possible later-phase recovery were observed in both studies.…”