Whitney S Gibbs1, Rachel A Weber2, Rick G Schnellmann3, DeAnna L Adkins4. 1. Department of Drug Discovery and Biomedical Sciences, Medical University of South Carolina, Charleston SC, United States. 2. Department of Neuroscience, Medical University of South Carolina, Charleston SC, United States. 3. Ralph H. Johnson VA Medical Center, Charleston, SC, United States; Department of Pharmacy & Toxicology, College of Pharmacy, University of Arizona, Tucson, AZ, United States. Electronic address: schnell@pharmacy.arizona.edu. 4. Department of Neuroscience, Medical University of South Carolina, Charleston SC, United States; Center of Biomedical Imaging, Medical University of South Carolina, Charleston SC, United States; Health Sciences and Research, College of Health Professions, Medical University of South Carolina, Charleston, SC, United States. Electronic address: adkinsdl@musc.edu.
Abstract
AIMS: Determine the subacute time course of mitochondria disruption, cell death, and inflammation in a rat model of unilateral motor cortical ischemic stroke. MAIN METHODS: Rats received unilateral ischemia of the motor cortex and were tested on behavioral tasks to determine impairments. Animals were euthanized at 24h, 72h and 144h and mRNA expression of key mitochondria proteins and indicators of inflammation, apoptosis and potential regenerative processes in ipsilesion cortex and striatum, using RT-qPCR. Mitochondrial proteins were examined at 144h using immunoblot analysis. KEY FINDINGS: Rats with stroke induced-behavioral deficits had sustained, 144h post-lesion, decreases in mitochondrial-encoded electron transport chain proteins NADH dehydrogenase subunit-1 and cytochrome c oxidase subunit-1 (mRNA and protein) and mitochondrial DNA content in perilesion motor and sensory cortex. Uncoupling-protein-2 gene expression, but not superoxide dismutase-2, remained elevated in ipsilateral cortex and striatum at this time. Cortical inflammatory cytokine, interleukin-6, was increased early and was followed by increased macrophage marker F4/80 after stroke. Cleaved caspase-3 activation was elevated in cortex and growth associated protein-43 was elevated in the cortex and striatum six days post-lesion. SIGNIFICANCE: We identified a relationship between three disrupted pathways, (1) sustained loss of mitochondrial proteins and mitochondrial DNA copy number in the cortex linked to decreased mitochondrial gene transcription; (2) early inflammatory response mediated by interleukin- 6 followed by macrophages; (3) apoptosis in conjunction with the activation of regenerative pathways. The stroke-induced spatial and temporal profiles lay the foundation to target pharmacological therapeutics to these three pathways.
AIMS: Determine the subacute time course of mitochondria disruption, cell death, and inflammation in a rat model of unilateral motor cortical ischemic stroke. MAIN METHODS:Rats received unilateral ischemia of the motor cortex and were tested on behavioral tasks to determine impairments. Animals were euthanized at 24h, 72h and 144h and mRNA expression of key mitochondria proteins and indicators of inflammation, apoptosis and potential regenerative processes in ipsilesion cortex and striatum, using RT-qPCR. Mitochondrial proteins were examined at 144h using immunoblot analysis. KEY FINDINGS:Rats with stroke induced-behavioral deficits had sustained, 144h post-lesion, decreases in mitochondrial-encoded electron transport chain proteins NADH dehydrogenase subunit-1 and cytochrome c oxidase subunit-1 (mRNA and protein) and mitochondrial DNA content in perilesion motor and sensory cortex. Uncoupling-protein-2 gene expression, but not superoxide dismutase-2, remained elevated in ipsilateral cortex and striatum at this time. Cortical inflammatory cytokine, interleukin-6, was increased early and was followed by increased macrophage marker F4/80 after stroke. Cleaved caspase-3 activation was elevated in cortex and growth associated protein-43 was elevated in the cortex and striatum six days post-lesion. SIGNIFICANCE: We identified a relationship between three disrupted pathways, (1) sustained loss of mitochondrial proteins and mitochondrial DNA copy number in the cortex linked to decreased mitochondrial gene transcription; (2) early inflammatory response mediated by interleukin- 6 followed by macrophages; (3) apoptosis in conjunction with the activation of regenerative pathways. The stroke-induced spatial and temporal profiles lay the foundation to target pharmacological therapeutics to these three pathways.
Authors: Lech Wojtczak; Magdalena Lebiedzińska; Jan M Suski; Mariusz R Więckowski; Peter Schönfeld Journal: Biochem Biophys Res Commun Date: 2011-03-31 Impact factor: 3.575