Abstract WP96: The Histone Deacetylase Inhibitor, Sodium Butyrate, Exhibits Biphasic Neuroprotective Mechanisms in the Acute Phase of Ischemic Stroke in Middle-Aged Female Rats

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Min Jung Park ◽  
Farida Sohrabji
Keyword(s):  
Histone Deacetylase ◽  
Acute Phase ◽  
Sodium Butyrate ◽  
Hdac Inhibitor ◽  
Female Rats ◽  
Middle Aged ◽  
Peripheral Tissues ◽  
Post Stroke ◽  
Sensory Motor ◽  
Anti Inflammatory

Introduction: Sodium butyrate (NaB) is a histone deacetylase (HDAC) inhibitor exhibiting anti-inflammatory and neuroprotective effects in a rat ischemic model of a myocardial ischemia as well as stroke. Although clinical evidence shows that older women are at higher risk for stroke occurrence and greater stroke severity, no studies have evaluated the effectiveness of NaB either in females or in older animals. Methods: To determine the effects of NaB on stroke in older females, acyclic middle-aged Sprague-Dawley female rats (10-12 months old, constant diestrus) were subject to middle cerebral artery occlusion (MCAo) by intracerebral injection of recombinant endothelin-1. Rats were treated with NaB (300 mg/kg, i.p.) at 6h and 30h following ET-1 injection. Animals were tested for sensory motor performance pre and post stroke. Subsequently, rats were sacrificed at the early (2d) or late (5d) acute phase after MCAo. Serum and tissue samples were collected for biochemical analyses. Results: NaB treatment reduced infarct volume and ameliorated stroke-induced sensory motor impairment in middle-aged female rats post MCAo. At the early acute phase, NaB treatment decreased brain lipid peroxides, and reduced serum levels of GFAP, a marker of blood brain barrier permeability. NaB also reduced expression of the inflammatory cytokine IL-1beta in circulation and IL-18 in the ischemic hemisphere. At the late acute phase, NaB treatment further suppressed MCAo-induced increase of IL-1beta, IL-17A, and IL-18 in brain lysates (cortex and striatum) from the ischemic hemisphere, and decreased ischemia-induced upregulation of IL-1beta and IL-18 in circulation, indicating a potent anti-inflammatory effect of the HDAC inhibitor. Moreover, NaB treatment also increased expression of IGF-1, a known neuroprotectant, in peripheral tissues including serum, liver, and spleen. Conclusions: These data provide the first evidence that delayed (> 6h) NaB treatment post-stroke is neuroprotective in older female rats. Importantly, these data also show that in addition to its well-known anti-inflammatory actions, NaB may exert a biphasic effect after stroke, operating initially to reduce oxidative stress in the brain, and later, elevating IGF-1 expression in peripheral tissues.

Abstract WMP42: Astrocyte Specific rAAV-mediated Insulin-Like Growth Factor-1 Expression in Aging Female Rats Increases Post-Stroke Survival and Sensory Motor Performance

Stroke ◽  
2016 ◽  
Vol 47 (suppl_1) ◽  
Author(s):  
Andre K Okoreeh ◽  
Shameena Bake ◽  
Farida Sohrabji
Keyword(s):  
Motor Performance ◽  
Low Dose ◽  
Female Rats ◽  
Specific Gene ◽  
High Dose ◽  
Middle Aged ◽  
Post Stroke ◽  
Post Surgery ◽  
Virus Serotype ◽  
Sensory Motor

Background and Purpose: Our previous work shows that middle aged female rats sustain larger strokes as compared to younger female rats. With age, circulating and brain parenchymal levels of IGF-1 are reduced. Exogenous IGF-1 treatment improves infarct volume in aging females. Our recent studies show that astrocytes from aging females synthesize less IGF-1. Here we tested the hypothesis that elevation of astrocyte derived IGF-1 would improve stroke impairment in older female rats. Methods: Middle-aged (10-12 month old; acyclic) female rats were injected with adeno-associated virus serotype 5 (rAAV5) into the cortex and striatum. rAAV5 was packaged with the coding sequence of the IGF-1 gene downstream of an astrocyte-specific gene (GFAP). The construct contained the mCherry reporter gene. Control rAAV consisted of an identical shuttle vector construct without the IGF-1 gene. In separate experiments, two titers of virus were injected: high dose (5 X 10 12 VP/mL) or low dose (5 X 10 11 VP/mL). Three to four weeks after injection, middle-cerebral artery occlusion via an intraluminal suture for ninety minutes was performed followed by reperfusion. Post-surgery survival was monitored as well as sensory motor function using the vibrissae evoked forelimb placement task. Results: Specificity of IGF-1 expression was confirmed by visualization of the mCherry reporter under fluorescent illumination and immunohistochemistry. Post stroke survival was improved in animals that received the high dose rAAV-IGF-1 animals a 5-day period (p<0.001). Low dose rAAV-IGF-1 did not affect post stroke survival, however sensory motor performance was preserved in this group. In low dose control animals, ischemic stroke impaired performance on the vibrissae evoked forelimb placement task. Impairment was seen in the same-side and cross-midline task performance on the limb contralateral to the infarct and cross midline task on the limb ipsilateral to the infarcted side (p<0.05). No significant deficits were seen in the rAAV-IGF-1 low dose treated animals. Conclusion: These data support the hypothesis that increasing astrocytic IGF-1 in aging females improves post stroke survival and behavior outcomes.

Abstract WP108: Astrocyte-specific rAAV-mediated Insulin-like Growth Factor-1 Expression in Aging Female Rats Alters Stroke-induced Brain Immune Profile and Reduces Motor Impairment

Stroke ◽  
2017 ◽  
Vol 48 (suppl_1) ◽  
Author(s):  
Andre K Okoreeh ◽  
Shameena Bake ◽  
Farida Sohrabji
Keyword(s):  
Flow Cytometry ◽  
Growth Factor ◽  
Immune Cells ◽  
Motor Impairment ◽  
Female Rats ◽  
Insulin Like Growth Factor ◽  
Middle Aged ◽  
Post Stroke ◽  
Sensory Motor ◽  
The Brain

Introduction: Middle-aged female rats sustain larger strokes than younger female rats. This may be due to age-related loss of circulating and parenchymal brain levels of insulin like growth factor-1 (IGF-1). With age, IGF-1 synthesis is decreased in astrocytes, a critical cell type for post-stroke recovery. Here we tested the hypothesis that replenishing IGF-1 in aging astrocytes will improve stroke outcomes by influencing the type and extent of immune cells infiltration into the brain post-stroke. Methods: Middle-aged (10-12 mo old, acyclic) female rats were injected into the striatum and cortex with adeno-associated virus serotype 5 (rAAV5) packaged with the coding sequence of the hIGF-1 gene downstream of an astrocyte-specific promoter (GFAP). The rAAV-control consisted of an identical shuttle vector construct without the hIGF-1 gene. Three to four weeks later, animals underwent 90 minute transient middle cerebral artery occlusion via intraluminal suture. At 2d post stroke, flow cytometry was used to determine the type and extent of peripheral immune cells trafficked into the brain. In parallel studies, animals were tested for performance on sensory motor tasks at 2d and 5 days after MCAo. Results: rAAV-mediated IGF-1 expression was confirmed in astrocytes with RT-PCR. Flow cytometry analysis of immune cells in the brain at 24h post-stroke found that proportion of Treg cells was greater in animals with rAAV-IGF-1 as compared to rAAV-controls. Additionally, while there was no difference in the proportion of M2 microglia, rAAV-IGF-1 enhanced M2 infiltrating macrophages. At 2d and 5d post stroke, stroke-induced sensory motor impairment was reduced in animals with rAAV-IGF-1 as compared to rAAV-controls. Conclusion: Targeted enhancement of IGF-1 in astrocytes of middle-aged females improved stroke-induced behavioral impairment concomitant with recruitment of anti-inflammatory cell types to the ischemic brain.

scholarly journals Functional Assessment of Stroke-Induced Regulation of miR-20a-3p and Its Role as a Neuroprotectant

2021 ◽  
Author(s):  
Taylor E. Branyan ◽  
Amutha Selvamani ◽  
Min Jung Park ◽  
Kriti E. Korula ◽  
Kelby F. Kosel ◽  
...  
Keyword(s):  
Motor Behavior ◽  
Mitochondrial Dynamics ◽  
Infarct Volume ◽  
Neuron Specific Enolase ◽  
Cell Types ◽  
Female Rats ◽  
Therapeutic Window ◽  
Middle Aged ◽  
Stroke Outcomes ◽  
Sensory Motor

AbstractMicroRNAs have gained popularity as a potential treatment for many diseases, including stroke. This study identifies and characterizes a specific member of the miR-17–92 cluster, miR-20a-3p, as a possible stroke therapeutic. A comprehensive microRNA screening showed that miR-20a-3p was significantly upregulated in astrocytes of adult female rats, which typically have better stroke outcomes, while it was profoundly downregulated in astrocytes of middle-aged females and adult and middle-aged males, groups that typically have more severe stroke outcomes. Assays using primary human astrocytes and neurons show that miR-20a-3p treatment alters mitochondrial dynamics in both cell types. To assess whether stroke outcomes could be improved by elevating astrocytic miR-20a-3p, we created a tetracycline (Tet)-induced recombinant adeno-associated virus (rAAV) construct where miR-20a-3p was located downstream a glial fibrillary acidic protein promoter. Treatment with doxycycline induced miR-20-3p expression in astrocytes, reducing mortality and modestly improving sensory motor behavior. A second Tet-induced rAAV construct was created in which miR-20a-3p was located downstream of a neuron-specific enolase (NSE) promoter. These experiments demonstrate that neuronal expression of miR-20a-3p is vastly more neuroprotective than astrocytic expression, with animals receiving the miR-20a-3p vector showing reduced infarction and sensory motor improvement. Intravenous injections, which are a therapeutically tractable treatment route, with miR-20a-3p mimic 4 h after middle cerebral artery occlusion (MCAo) significantly improved stroke outcomes including infarct volume and sensory motor performance. Improvement was not observed when miR-20a-3p was given immediately or 24 h after MCAo, identifying a unique delayed therapeutic window. Overall, this study identifies a novel neuroprotective microRNA and characterizes several key pathways by which it can improve stroke outcomes.

Abstract TP104: Post Stroke Depressive-Like Behaviors in Middle-Aged Female Rats is Associated With Gut Dysbiosis and Improved by Mir363-3p

Stroke ◽  
2020 ◽  
Vol 51 (Suppl_1) ◽  
Author(s):  
Courtney Stewart ◽  
Aditya Panta ◽  
Taylor Branyan ◽  
Farida Sohrabji
Keyword(s):  
Cell Proliferation ◽  
Dentate Gyrus ◽  
Forced Swim Test ◽  
Female Rats ◽  
Middle Aged ◽  
16S Sequencing ◽  
Post Stroke ◽  
Hippocampal Cell ◽  
Affective Behaviors ◽  
Post Stroke Depression

Background: Post-stroke depression (PSD) occurs in one-third of stroke survivors, is more prevalent in women, and negatively impacts quality of life and recovery. Our previous work showed that acyclic middle-aged female rats display depressive behaviors after stroke, and IV treatment with mir363-3p attenuates these behaviors. Serotonin has been implicated in affective behaviors, and loss of this neurotransmitter is also associated with decreased neurogenesis in the hippocampus. The present study determined (a) whether stroke affected tryptophan, a gut metabolite, and precursor for serotonin, and cell proliferation in the hippocampus and (b) whether serum tryptophan levels and hippocampal cell proliferation was restored by mir363-3p. Methods: Ischemic stroke was induced by stereotaxic delivery of endothelin-1 to the MCA of middle-aged female rats. Animals received a single injection of mir363-3p or scrambled oligos 4h after stroke. Depressive-like behaviors were assessed by the Effort-based sucrose consumption test, Social Interaction and Forced Swim Test 3 months after stroke. Blood was collected at termination. Serum tryptophan levels were quantified by ELISA. Bacterial composition was analyzed by 16S sequencing of fecal samples. Ki67 immunohistochemistry was performed on brain tissue collected at termination and quantified within the dentate gyrus by two blind observers. Results: Animals subjected to stroke exhibited depressive-like behaviors and had decreased tryptophan levels as compared to sham treated animals. This is also accompanied by microbiota dysbiosis as measured by an elevated ratio of Firmicutes to Bacteroidetes. Mir363-3p treatment increased tryptophan levels as compared to scrambled controls and were no different from sham (non-stroke) animals. Moreover, miR363-3p treated rats exhibit a significantly more dentate gyrus-specific Ki67 expression a proliferation marker. Conclusions: Together, these data indicate that miR363-3p attenuates post stroke depression via a mechanism that prevents microbiota dysbiosis and increases hippocampal cell proliferation.

Estrogen-induced neuroprotective and anti-inflammatory effects are dependent on the brain areas of middle-aged female rats

2016 ◽  
Vol 124 ◽  
pp. 238-253 ◽  
Author(s):  
Uday P. Pratap ◽  
Anushree Patil ◽  
Himanshu R. Sharma ◽  
Lalgi Hima ◽  
Ramanathan Chockalingam ◽  
...  
Keyword(s):  
Female Rats ◽  
Middle Aged ◽  
Brain Areas ◽  
Anti Inflammatory ◽  
The Brain

scholarly journals Mir363-3p attenuates post-stroke depressive-like behaviors in middle-aged female rats

2019 ◽  
Vol 78 ◽  
pp. 31-40 ◽  
Author(s):  
Aditya Panta ◽  
Sivani Pandey ◽  
Irma N. Duncan ◽  
Shaelynn Duhamel ◽  
Farida Sohrabji
Keyword(s):  
Female Rats ◽  
Middle Aged ◽  
Post Stroke

Intermittent fasting combined with supplementation with Ayurvedic herbs reduces anxiety in middle aged female rats by anti-inflammatory pathways

2017 ◽  
Vol 18 (4) ◽  
pp. 601-614 ◽  
Author(s):  
Harpal Singh ◽  
Taranjeet Kaur ◽  
Shaffi Manchanda ◽  
Gurcharan Kaur
Keyword(s):  
Female Rats ◽  
Intermittent Fasting ◽  
Middle Aged ◽  
Inflammatory Pathways ◽  
Anti Inflammatory

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 ◽  
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.

Abstract T P240: Intravenous Injections of Microrna 363 Mimic Promotes Neuroprotection in Middle Aged Females in an Ischemic Stroke Model

Stroke ◽  
2015 ◽  
Vol 46 (suppl_1) ◽  
Author(s):  
Amutha Selvamani ◽  
Farida Sohrabji
Keyword(s):  
Infarct Volume ◽  
Expression Patterns ◽  
Elevated Serum ◽  
Treated Group ◽  
Female Rats ◽  
Pcr Analysis ◽  
Circulating Microrna ◽  
Middle Aged ◽  
Post Stroke ◽  
Male And Female Rats

Background: Analysis of circulating microRNA in young and middle aged male and female rats revealed distinct expression patterns of post-stroke microRNAs (Selvamani et al., 2014). Mir-363 expression was inversely related to infarct volume, such that adult females, who display the smallest infarct volumes, had the highest expression of miR363. Based on this association, we hypothesized that mir-363 may promote survival of ischemic neurons. As proof of concept, the present study utilized middle aged females to investigate the role of miR-363 in neuroprotection. Methods: Middle aged (12 mo) female rats were subject to middle cerebral artery occlusion (MCAo). At 4h post-stroke, animals received a tail-vein injection of miR-363 or scrambled control. Vibrissae-elicited forelimb placement (VIB) test was performed pre and post MCAo to assess motor deficits. Blood samples were drawn at 2d and 5d post stroke. All animals were terminated at 5d post MCAo and the brains processed for infarct analysis by standard histological procedures. Total RNA isolated from serum and brain was subject to QPCR amplification for miR-363 and U6 (normalization control) Results: IV injections of mir363 significantly elevated serum expression of this microRNA as compared to animals injected with scrambles control oligos, when measured 2d post stroke. Infarct volumes (cortex and striatum), at 5d post stroke, were significantly reduced in the miR-363 treated group as compared to controls (p ≤ 0.001). VIB-test indicated significant motor recovery post-stroke in the contralateral limb in miR-363 mimic treated group as compared to controls. RT-PCR analysis of brain tissue showed higher expression of miR-363 in the left (ischemic) hemisphere in the miR-363 mimic group while, no difference was observed in the non-ischemic, indicating that the mimetic is recruited to the ischemic site. Conclusion: The present study underscores the value of miRNA profiling in populations with different stroke outcomes as a strategy to identify new therapeutic targets for stroke.

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