Optimising the Photothrombotic Model of Stroke in the C57BI/6 and FVB/N Strains of Mouse

Abstract The photothrombotic stroke model relies on the interaction between photosensitive-dye and light for clot formation. Interestingly, the relationship between the length of light exposure and stroke-outcome has never been examined. This model has yet to be established in the FVB/N strain, even though stroke-outcomes are strain-specific. Therefore, this study aimed to examine the effect of different lengths of light exposure in two strains of mice on photothrombotic stroke. Male FVB/N and C57Bl/6 mice were subjected to stroke using 15, 18, or 20-mins light exposure. Mice underwent functional testing for up to 7 days. Infarct volume was assessed with thionin staining, and cellular responses to injury analysed via immunofluorescence. Blood brain barrier (BBB) breakdown was assessed using Evans blue dye. Increasing light exposure from 15 to 20-minutes increased infarct volume but not functional deficit. Interestingly, there were strain-specific differences in functional outcomes, with FVB/N mice having less deficit on the hanging wire test than C57BI/6 after 15-minutes of light exposure. The opposite was seen in the adhesive removal test. There was no difference in number of neurons, astrocytes, microglia, macrophages, and T cells between the strains, despite FVB/N mice demonstrating greater BBB breakdown and an enlarged spleen post-stroke. Increasing light exposure systematically increases infarct volume but does not worsen functional outcomes. FVB/N and C57Bl/6 mice exhibit subtle differences in functional outcomes post stroke, which highlights the need to choose tests which are appropriate for the mouse strain being used.

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Diet-induced vitamin D deficiency has no effect on acute post-stroke outcomes in young male mice

Journal of Cerebral Blood Flow & Metabolism ◽

10.1177/0271678x17719208 ◽

2017 ◽

Vol 38 (11) ◽

pp. 1968-1978 ◽

Cited By ~ 5

Author(s):

Megan A Evans ◽

Hyun Ah Kim ◽

T Michael De Silva ◽

Thiruma V Arumugam ◽

Andrew N Clarkson ◽

...

Keyword(s):

Vitamin D ◽

Vitamin D Deficiency ◽

Immune Cells ◽

Functional Outcomes ◽

Infarct Volume ◽

Control Group ◽

Deficient Diet ◽

Stroke Outcomes ◽

Post Stroke ◽

Vitamin D Levels

Recent observational studies have reported that patients with low circulating levels of vitamin D experience larger infarct volumes and worse functional outcomes after ischemic stroke compared to those with sufficient levels. However, it is unknown whether a causal relationship exists between low vitamin D levels and poor stroke outcome. This study aimed to assess the effect of vitamin D deficiency on acute outcomes post-stroke. Male C57Bl6 mice (six week old) were assigned to either a control or vitamin D deficient diet for four weeks prior to stroke. Stroke was induced by 1 h middle cerebral artery occlusion (MCAO) with reperfusion. At 24 h, we assessed functional outcomes, infarct volume, quantified immune cells in the brain by immunofluorescence and examined susceptibility to lung infection. ELISAs showed that the plasma level of hydroxyvitamin D3 was 85% lower in mice fed the vitamin D-deficient diet compared with the control group. Despite this, vitamin D deficiency had no impact on functional outcomes or infarct volume after stroke. Further, there were no differences in the numbers of infiltrating immune cells or bacterial load within the lungs. These data suggest that diet-induced vitamin D deficiency has no effect on acute post-stroke outcomes.

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Abstract 59: Post-stroke Delivery of Microrna-363 to Middle-aged Female Rats is Internalized by Neurons and Suppresses the Cell Death Effector Pathway

Stroke ◽

10.1161/str.48.suppl_1.59 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Amutha Selvamani ◽

Farida Sohrabji

Keyword(s):

Cell Death ◽

Caspase 3 ◽

Infarct Volume ◽

Cell Types ◽

Female Rats ◽

Middle Aged ◽

Stroke Outcomes ◽

Post Stroke ◽

Double Label ◽

Death Effector

Background: MicroRNAs serve as translational inhibitors and offer a unique therapeutic target for acute diseases such as stroke. Profiling of circulating miRNA after stroke identified mir363, whose expression was inversely correlated with infarct volume. Middle aged female rats show worse stroke outcomes than younger females and have much lower levels of mir363. Our recent studies showed that iv injections of miR363 mimic to middle aged females, significantly improved stroke outcome. The present study is designed to determine the mechanisms by which miR-363 acts as a therapeutic miR. Methods: Middle aged (12 mo) females were subject to MCAo. At 4h post-stroke, animals received a tail-vein injection of miR-363-3p FAM or scrambled control. Animals were terminated at 48h or 5d post-MCAo and perfused transcardially or processed for protein, respectively. To determine which neural cell types localized exogenous mir363-3p, combined immunofluorescence was performed for cell specific markers (neuronal (NeuN), astrocytic (GFAP), microglial (CD11b) and endothelial (PECAM)) and mir363-3p-FAM mimic on coronal brain sections (25 mm thickness). Protein lysates from the ischemic tissue was analyzed for caspase-3 expression by Western blot analysis. Results: FAM-labeled mir363-3p was widely detected in the forebrain. The majority of NeuN+ cells in the cortex and striatum were also labeled with FAM-363-3p, indicating a robust internalization of the mimic in neurons. FAM-mir363-3p was also localized to a few microglia (CD11b +), virtually no double-label was seen in astrocytes and endothelial cells. Mir363 decreased the expression and functional activity of caspase3 in the ischemic hemisphere. Conclusion: Collectively, the data suggests that exogenous miR-363-3p is shuttled to the brain and is preferentially internalized by neurons. Together with the caspase-3 regulation, our data suggests that mir363 may improve stroke outcomes by suppressing a cell death effector.

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Abstract P813: Enhanced Stress Response is Associated With Increased Inflammation and Worse Outcomes Following Ischemic Stroke in Diabetic Condition

Stroke ◽

10.1161/str.52.suppl_1.p813 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Eunhee Kim ◽

Sehee Kim ◽

Eunsu Park ◽

Peng R Chen

Keyword(s):

Stress Response ◽

Hpa Axis ◽

Infarct Volume ◽

Plasma Corticosterone ◽

Neurological Deficits ◽

Stroke Severity ◽

Diabetic Mice ◽

Stroke Outcomes ◽

Ischemic Brain ◽

Post Stroke

Introduction: Although stroke severity is increased in patients with diabetes (e.g., higher mortality, larger infarcts, and worse neurological deficits), the underlying mechanism(s) of the worse outcomes is not clear. Evidence shows that hypothalamic-pituitary-adrenal (HPA) axis is dysregulated and cortisol levels are increased in diabetes. Based on the role of HPA axis in immunity, we hypothesized that diabetes-enhanced stress response contributes to stroke injury via regulating inflammation. Methods: Diabetes was induced in C57BL/6 mice by feeding a diabetogenic diet and injecting streptozotocin. Mice were subjected to 30 min middle cerebral artery occlusion. Infarct volume and neurological scores were measured at 24h-post stroke. We measured expression of factors related to stress response, plasma corticosterone, c-Fos and corticotropin-releasing factor (CRH) in hypothalamus, and proopiomelanocortin (POMC) and corticotropin-releasing hormone receptor 1 (CRHR1) in pituitary. Inflammatory cytokine levels were also determined in the ischemic brain. Results: Diabetic mice showed hyperglycemia and delayed glucose clearance in blood. At 1d-post stroke, diabetic mice showed larger infarct and worse neurological score. Plasma corticosterone levels were significantly increased in diabetic mice. We also found increased c-Fos in hypothalamus, and CRHR1 and POMC in pituitary. These were accompanied by increased IL-1β, TNF-α, and IL-6 mRNA in the ischemic brain. Conclusion: Our results indicate that stress response is enhanced in diabetic conditions, and associated with increased inflammation in ischemic brain and worse stroke outcomes. It suggests that regulation of stress response may improve stroke outcomes in diabetic conditions.

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Post-Stroke Depression and Its Effect on Functional Outcomes during Inpatient Rehabilitation

Journal of Neurosciences in Rural Practice ◽

10.1055/s-0041-1731958 ◽

2021 ◽

Author(s):

Gurumayum Sonachand Sharma ◽

Anupam Gupta ◽

Meeka Khanna ◽

Naveen Bangarpet Prakash

Keyword(s):

Outcome Measures ◽

Functional Outcomes ◽

Rating Scale ◽

Tertiary Care ◽

Depression Scale ◽

Inpatient Rehabilitation ◽

University Hospital ◽

Post Stroke ◽

Significant Difference ◽

Post Stroke Depression

Abstract Objective The aim of the study is to observe the effect of post-stroke depression on functional outcomes during inpatient rehabilitation. Patients and Methods The design involved is prospective observational study. The location involved is Neurological Rehabilitation unit in a tertiary care university hospital. The study period ranges from October 2019 to April 2020. The participants involved are the patients with first ever stroke, male and female with age ≥18 years and duration less than 1 year. All participants were assessed at admission and after 14 sessions of inpatient rehabilitation by depression subscale of Hospital Anxiety and Depression Scale (HADS-D) and Hamilton Depression Rating Scale (HDRS). The stroke outcomes measures used were: Barthel Index (BI), Scandinavian Stroke Scale (SSS), and Modified Rankin Scale (MRS). Results There are a total of 30 participants (18 males) with median stroke duration of 90 days. The median age of the patients was 58 years. Sixteen patients had ischemic and 14 had hemorrhagic stroke. Out of these, 57% (n = 17) had symptoms of depression (HADS-D >7). Participants in both groups (with and without depression) showed improvement in all the functional outcome measures (BI, SSS, MRS) at the time of discharge as compared with admission scores. The changes in the outcome measures were statistically significant within groups (p < 0.05) but not significant between the groups (p > 0.05). Conclusion The post-stroke depression is common among stroke survivors of less than 1 year duration. There was no significant difference in the functional outcomes between stroke patients with depression and those without depression with inpatient rehabilitation program.

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Stem cell treatment improves post stroke neurological outcomes: a comparative study in male and female rats

Stroke and Vascular Neurology ◽

10.1136/svn-2020-000834 ◽

2021 ◽

pp. svn-2020-000834

Author(s):

Koteswara Rao Nalamolu ◽

Bharath Chelluboina ◽

Casimir A Fornal ◽

Siva Reddy Challa ◽

David M Pinson ◽

...

Keyword(s):

Stem Cells ◽

Sex Differences ◽

Motor Function ◽

Infarct Volume ◽

Female Rats ◽

Human Umbilical Cord ◽

Male And Female ◽

Post Stroke ◽

Male And Female Rats ◽

Males And Females

Background and purposeThe therapeutic potential of different stem cells for ischaemic stroke treatment is intriguing and somewhat controversial. Recent results from our laboratory have demonstrated the potential benefits of human umbilical cord blood-derived mesenchymal stem cells (MSC) in a rodent stroke model. We hypothesised that MSC treatment would effectively promote the recovery of sensory and motor function in both males and females, despite any apparent sex differences in post stroke brain injury.MethodsTransient focal cerebral ischaemia was induced in adult Sprague-Dawley rats by occlusion of the middle cerebral artery. Following the procedure, male and female rats of the untreated group were euthanised 1 day after reperfusion and their brains were used to estimate the resulting infarct volume and tissue swelling. Additional groups of stroke-induced male and female rats were treated with MSC or vehicle and were subsequently subjected to a battery of standard neurological/neurobehavioral tests (Modified Neurological Severity Score assessment, adhesive tape removal, beam walk and rotarod). The tests were administered at regular intervals (at days 1, 3, 5, 7 and 14) after reperfusion to determine the time course of neurological and functional recovery after stroke.ResultsThe infarct volume and extent of swelling of the ischaemic brain were similar in males and females. Despite similar pathological stroke lesions, the clinical manifestations of stroke were more pronounced in males than females, as indicated by the neurological scores and other tests. MSC treatment significantly improved the recovery of sensory and motor function in both sexes, and it demonstrated efficacy in both moderate stroke (females) and severe stroke (males).ConclusionsDespite sex differences in the severity of post stroke outcomes, MSC treatment promoted the recovery of sensory and motor function in male and female rats, suggesting that it may be a promising treatment for stroke.

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Interactions between hippocampal activity and striatal dopamine in people at clinical high risk for psychosis: relationship to adverse outcomes

Neuropsychopharmacology ◽

10.1038/s41386-021-01019-0 ◽

2021 ◽

Author(s):

Gemma Modinos ◽

Anja Richter ◽

Alice Egerton ◽

Ilaria Bonoldi ◽

Matilda Azis ◽

...

Keyword(s):

High Risk ◽

Functional Outcomes ◽

Mental States ◽

Adverse Outcomes ◽

Striatal Dopamine ◽

Psychotic Symptoms ◽

Dopamine Synthesis ◽

Clinical High Risk ◽

Hippocampal Activity ◽

The Relationship

AbstractPreclinical models propose that increased hippocampal activity drives subcortical dopaminergic dysfunction and leads to psychosis-like symptoms and behaviors. Here, we used multimodal neuroimaging to examine the relationship between hippocampal regional cerebral blood flow (rCBF) and striatal dopamine synthesis capacity in people at clinical high risk (CHR) for psychosis and investigated its association with subsequent clinical and functional outcomes. Ninety-five participants (67 CHR and 28 healthy controls) underwent arterial spin labeling MRI and 18F-DOPA PET imaging at baseline. CHR participants were followed up for a median of 15 months to determine functional outcomes with the global assessment of function (GAF) scale and clinical outcomes using the comprehensive assessment of at-risk mental states (CAARMS). CHR participants with poor functional outcomes (follow-up GAF < 65, n = 25) showed higher rCBF in the right hippocampus compared to CHRs with good functional outcomes (GAF ≥ 65, n = 25) (pfwe = 0.026). The relationship between rCBF in this right hippocampal region and striatal dopamine synthesis capacity was also significantly different between groups (pfwe = 0.035); the association was negative in CHR with poor outcomes (pfwe = 0.012), but non-significant in CHR with good outcomes. Furthermore, the correlation between right hippocampal rCBF and striatal dopamine function predicted a longitudinal increase in the severity of positive psychotic symptoms within the total CHR group (p = 0.041). There were no differences in rCBF, dopamine, or their associations in the total CHR group relative to controls. These findings indicate that altered interactions between the hippocampus and the subcortical dopamine system are implicated in the pathophysiology of adverse outcomes in the CHR state.

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The Relationship of Psychiatric Symptoms with Performance-Based and Self-Reported Cognitive Function After Ischemic Stroke

Journal of the International Neuropsychological Society ◽

10.1017/s1355617721000187 ◽

2021 ◽

pp. 1-13

Author(s):

Elisabeth Kliem ◽

Elise Gjestad ◽

Truls Ryum ◽

Alexander Olsen ◽

Bente Thommessen ◽

...

Keyword(s):

Ischemic Stroke ◽

Executive Function ◽

Depressive Symptoms ◽

Cognitive Function ◽

Psychiatric Symptoms ◽

Post Stroke ◽

Cognitive Difficulties ◽

Memory And Attention ◽

Relationship Of ◽

The Relationship

Abstract Objective: Findings on the relationship of psychiatric symptoms with performance-based and self-reported cognitive function post-stroke are inconclusive. We aimed to (1) study the relation of depression and anxiety to performance-based cognitive function and (2) explore a broader spectrum of psychiatric symptoms and their association with performance-based versus self-reported cognitive function. Method: Individuals with supratentorial ischemic stroke performed neuropsychological examination 3 months after stroke. For primary analyses, composite scores for memory and attention/executive function were calculated based on selected neuropsychological tests, and the Hospital Anxiety and Depression Scale (HADS) was used. Psychiatric symptoms and self-reported cognitive function for secondary aims were assessed using the Symptom-Checklist-90 – Revised (SCL-90-R). Results: In a sample of 86 patients [mean (M) age: 64.6 ± 9.2; Mini-Mental State Examination (MMSE), 3–7 days post-stroke: M = 28.4 ± 1.7; National Institutes of Health Stroke Scale (NIHSS) after 3 months: M = 0.7 ± 1.6] depressive symptoms (HADS) were associated with poorer memory performance after controlling for age, sex, and education (p ≤ .01). In a subsample (n = 41; Age: M = 65.7 ± 8.1; MMSE: M = 28.4 ± 1.8; NIHSS: M = 1.0 ± 1.9), symptoms of phobic anxiety (SCL-90-R) were associated with poorer performance-based memory and attention/executive function, and symptoms of anxiety (SCL-90-R) with lower attention/executive function. Higher levels of self-reported cognitive difficulties were associated with higher scores in all psychiatric domains (p ≤ .05). Conclusion: Even in relatively well-functioning stroke patients, depressive symptoms are associated with poorer memory. The results also suggest that various psychiatric symptoms are more related to self-reported rather than to performance-based cognitive function. Screening for self-reported cognitive difficulties may not only help to identify patients with cognitive impairment, but also those who need psychological treatment.

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Inspiratory loading does not accelerate dystrophy inmdx mouse diaphragm: implications for regenerative therapy

Journal of Applied Physiology ◽

10.1152/japplphysiol.00689.2002 ◽

2003 ◽

Vol 94 (2) ◽

pp. 411-419 ◽

Cited By ~ 6

Author(s):

Alexander S. Krupnick ◽

Jianliang Zhu ◽

Taitan Nguyen ◽

Daniel Kreisel ◽

Keki R. Balsara ◽

...

Keyword(s):

Therapeutic Strategy ◽

Mdx Mouse ◽

Mdx Mice ◽

Blue Dye ◽

Regenerative Therapy ◽

Regenerative Capacity ◽

Progressive Degeneration ◽

Mouse Diaphragm ◽

The Relationship

Since the finding that the mdx mouse diaphragm, in contrast to limb muscles, undergoes progressive degeneration analogous to that seen in Duchenne muscular dystrophy, the relationship between the workload on a muscle and the pathogenesis of dystrophy has remained controversial. We increased the work performed by the mdx mouse diaphragm in vivo by tracheal banding and evaluated the progression of dystrophic changes in that muscle. Despite the establishment of dramatically increased respiratory workload and accelerated myofiber damage documented by Evans blue dye, no change in the pace of progression of dystrophy was seen in banded animals vs. unbanded, sham-operated controls. At the completion of the study, more centrally nucleated fibers were evident in the diaphragms of banded mdx mice than in sham-operated mdx controls, indicating that myofiber regeneration increases to meet the demands of the work-induced damage. These data suggest that there is untapped regenerative capacity in dystrophin-deficient muscle and validates experimental efforts aimed at augmenting regeneration within skeletal muscle as a therapeutic strategy in the treatment of dystrophinopathies.

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Abstract P777: Statistical Modeling of Proteomic Signaling During Stroke in Patients Undergoing Thrombectomy

Stroke ◽

10.1161/str.52.suppl_1.p777 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Sydney Claypoole ◽

Jacqueline Frank ◽

Madison Sands ◽

Christopher J McLouth ◽

Jill Roberts ◽

...

Keyword(s):

Ischemic Stroke ◽

Statistical Modeling ◽

Internal Control ◽

Stepwise Regression ◽

Infarct Volume ◽

Tissue Samples ◽

Bivariate Regression ◽

Inflammatory Proteins ◽

The Relationship ◽

Proximity Extension Assay

Introduction: The previously published Blood and Clot Thrombectomy Registry and Collaboration (BACTRAC) protocol (clinicaltrials.gov NCT03153683) utilizes mechanical thrombectomy to obtain tissue samples for banking. Peripheral blood proximal to the clot and intracranial blood distal from the clot were isolated. Proteomic and statistical analyses revealed normalized (intracranial-systemic) CCL19 expression was a predictor of infarct volume. Statistical modeling analyses were used determine the CCL19-associated proteomic signaling network occurring during ischemic stroke relating to infarct volume. Methods: Arterial intracranial and systemic blood samples underwent analysis for inflammatory proteins using Proximity Extension Assay (PEA) via Olink (Olink Proteomics, Boston, MA). Systemic expression was used as an internal control to normalize expression in the intracranial blood. Bivariate regression was used to examine the relationship between the intracranial normalized CCL19 expression and infarct volume. A backwards stepwise regression was then used to determine a model of predictability of infarct volume by CCL19 and associated inflammatory proteins. Results: 25 subjects (>18 yrs) with a mean infarct volume of 8,172 ± 82,284 mm 3 and mean infarct time of 513 ± 246 minutes were included in this study. Their median age was 64 (24-91) and 10 (40%) were male. 16 subjects (64%) had hypertension, 15 (60%) had BMI > 25, and 6 (24%) had a previous stroke. The stepwise regression model shows normalized expression of 16 proteins correlated with an increase in infarct volume (p<0.005): CCL20, CXCL1, OSM, CD6, OSMR, TGF-alpha, TRANCE, CXCL10, LIF-R, CCL19, CDCP1, Flt3L, CCL23, CD244, TRAIL, NOTCH1. Conclusions: In our model, the expression of these proteins were consistently changed, though the directionality differed. LIF-R, NOTCH1, TRAIL, CD6, CCL23, TGF-alpha, and CCL20 were positively correlated, while the expressions of Flt3L, OSM, OSMR, TRANCE, CD244, CDCP1, CXCL1, CXCL10, and CCL19 were negatively correlated with infarct volume. This model depicts the proteomic signaling occurring during stroke in relationship to infarct volume, which reveals potential biomarkers and therapeutic targets for the early phase of ischemic stroke.

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Abstract MP16: Excessive White Matter Hyperintensity Burden and Functional Outcomes After Acute Ischemic Stroke

Stroke ◽

10.1161/str.52.suppl_1.mp16 ◽

2021 ◽

Vol 52 (Suppl_1) ◽

Author(s):

Sungmin Hong ◽

Anne-katrin Giese ◽

Markus D Schirmer ◽

Adrian V Dalca ◽

Anna Bonkhoff ◽

...

Keyword(s):

Ischemic Stroke ◽

White Matter ◽

Acute Ischemic Stroke ◽

Functional Outcomes ◽

Life Time ◽

Stroke Recovery ◽

White Matter Hyperintensity ◽

Brain Health ◽

Stroke Outcomes ◽

The Brain

Objective: Ability of the brain to recover after an acute ischemic stroke (AIS) is linked to the pre-stroke burden of white matter hyperintensity (WMH), a radiographic marker of brain health. We sought to determine the excessive WMH burden in an AIS population and investigate its association with 3-month stroke outcomes. Data: We used 2,435 subjects from the MRI-GENIE study. Three-month functional outcomes of 872 subjects among those subjects were measured by 90-day modified Ranking Scale (mRS). Methods: We automatically quantified WMH volume (WMHv) on FLAIR images and adjusted for a brain volume. We modeled a trend using the factor analysis (FA) log-linear regression using age, sex, atrial fibrillation, diabetes, hypertension, coronary artery disease and smoking as input variables. We categorized three WMH burden groups based on the conditional probability given by the model (LOW: lower 33%, MED: middle 34%, and HIGH: upper 33%). The subgroups were compared with respect to mRS (median and dichotomized odds ratio (OR) (good/poor: mRS 0-2/3-6)). Results: Five FA components out of seven with significant relationship to WMHv (p<0.001) were used for the regression modeling (R 2 =0.359). The HIGH group showed higher median (median=2, IQR=2) mRS score than LOW (median=1, IQR=1) and MED (median=1, IQR=1). The odds (OR) of good AIS outcome for LOW and MED were 1.8 (p=0.0001) and 1.6 (p=0.006) times higher than HIGH, respectively. Conclusion: Once accounted for clinical covariates, the excessive WMHv was associated with worse 3-month stroke outcomes. These data suggest that a life-time of injury to the white matter reflected in WMH is an important factor for stroke recovery and an indicator of the brain health.

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