Abstract 142: Enhanced Neuroprotection by Synergistically Induced Hypothermia with Pharmacological and Physical Approach in Experimental Stroke

Background and Purpose: This study combined Transient Receptor Potential Vanilloid channel 1 (TRPV1) receptor agonist, dihydrocapsaicin (DHC), with physical hypothermia (PH) (ice pad) to achieve faster cooling to enhance its neuroprotective effects, thus potentially avoiding side effects brought on by monotherapies of high dose DHC and physical hypothermia. Methods: Middle cerebral artery (MCA) occlusion (2 h) was achieved using an intraluminal filament. Rats (n=8) were randomized to 7 groups: sham surgery, stroke only, PH, low DHC (0.5 mg/kg), low DHC/active rewarming (AR), high DHC (1.5 mg/kg) or combination (low DHC plus PH). The treatments were maintained for 3 h at the onset of reperfusion, which was 24 h. Rate to target hypothermia (31 °C) onset was measured. Extent of brain injury was determined by infarct volume, neurological deficit, and apoptotic cell death. Expressions of pro- and anti-apoptotic proteins were evaluated through Western blotting. Metabolic changes and oxidative injury were determined by ATP and ROS productions. Results: Combination had 28.6% faster cooling than PH, 350% faster than low DHC group and 200% faster than high DHC group. Combination had 63.2% reduction in infarct volume and low DHC had 25.9% reduction in infarct volume compared to stroke only. High DHC, DHC (AR) and PH and did not induce significant neuroprotection. Combination therapy significantly decreased apoptotic cell death by 48.5%, as compared to 24.9% with low DHC, in association with significantly increased anti-apoptotic and reduced pro-apoptotic protein expression. Combination therapy largely increased ATP levels by 42.9%, as compared to 25% increase with low DHC. Only combination therapy and PH had significant reductions in ROS at 6 and 24 h post-reperfusion. Neurological testing showed that combination therapy had the best outcomes at 24 h of reperfusion. Discussion: Combination of DHC and PH enhanced the neuroprotective effect produced by each alone. This synergistic protection is associated with faster cooling and more dramatic reduction in apoptotic cell death and more favorable cellular metabolism. The combination therapy is promising in clinical settings for its non-invasive, quick and effective outcomes.

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Abstract WP62: Enhanced Neuroprotection of Normobaric Oxygenation with Ethanol Conferred by Apoptosis Reduction in Acute Ischemic Stroke

Stroke ◽

10.1161/str.44.suppl_1.awp62 ◽

2013 ◽

Vol 44 (suppl_1) ◽

Author(s):

Sweena Parmar ◽

Xiaokun Geng ◽

Changya Peng ◽

Murali Guthikonda ◽

Yuchuan Ding

Keyword(s):

Cell Death ◽

Ischemic Stroke ◽

Acute Ischemic Stroke ◽

Caspase 3 ◽

Apoptotic Cell ◽

Neuroprotective Effect ◽

Apoptotic Cell Death ◽

Ethanol Administration ◽

Sprague Dawley ◽

Apoptotic Proteins

Objectives: Normobaric oxygenation (NBO) has been shown to provide neuroprotection in vivo and in vitro . Yet, a recent Phase 2 clinical trial investigating NBO therapy in acute ischemic stroke was terminated due to questionable therapeutic benefit. NBO therapy alone may be insufficient to produce improved outcomes. In our recent study, we demonstrated a strong neuroprotective effect of ethanol at a dose of 1.5 g/kg (equivalent to the human legal driving limit). In this study, we sought to identify whether low-dose ethanol administration enhances the neuroprotection offered by NBO and whether combined administration of NBO with ethanol is associated with reduced apoptosis. Methods: Sprague-Dawley rats were subjected to right middle cerebral artery occlusion (MCAO) for 2 h, followed by reperfusion. Ischemic animals received either an intraperitoneal injection of 1.0 g/kg ethanol, 2 h of 100% NBO, or both ethanol and NBO. The Cell Death Detection ELISA Assay (Roche) was performed to determine apoptotic cell death at 24 h after reperfusion. Levels of pro-apoptotic (Caspase-3, Bcl-2-associated X-BAX, and Apoptosis-Inducing Factor-AIF) and anti-apoptotic proteins (Bcl-2 and Bcl-xL) were determined by Western blot analysis at 3 and 24 h after reperfusion. Results: As expected, untreated ischemic rats had the highest apoptotic cell death. Combined NBO/ethanol therapy decreased cell death by 48%, as compared to 29% with ethanol and 22% with NBO. Similarly, combined NBO/ethanol therapy promoted the greatest expression of anti-apoptotic factors and the lowest expression of pro-apoptotic proteins at 3 h after reperfusion. This effect was maintained at 24 h and even more pronounced for AIF and Caspase-3. Conclusions: Given singularly, NBO and ethanol improved the degree of cell death, decreased the expression of pro-apoptotic proteins, and increased the expression of anti-apoptotic proteins. Yet, when administered together, their effects largely compounded. These results suggest a synergistic neuroprotection offered by NBO with ethanol, which may be attributed at least in part to their shared role in modulating neuronal apoptosis.

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The Neuroprotective Effect of GPR4 Inhibition through Attenuation of Caspase Mediated Apoptotic Cell Death in MPTP Induced Mouse Model of Parkinson’s Disease

10.20944/preprints202104.0223.v1 ◽

2021 ◽

Author(s):

Md. Ezazul Haque ◽

Shofiul Azam ◽

Mahbuba Akther ◽

Duk-Yeon Cho ◽

Kim In Su ◽

...

Keyword(s):

Cell Death ◽

Apoptotic Cell ◽

Neuroprotective Effect ◽

Neuronal Loss ◽

Apoptotic Cell Death ◽

Substantia Nigra Pars Compacta ◽

Motor Deficit ◽

Motor Deficits ◽

Mice Model ◽

Dopaminergic Neuronal Loss

GPR4, a member of proton activated GPCRs group. Previously we have reported that GPR4 is constitutively active at physiological pH and knockout of GPR4 has shown to protect dopaminergic neuronal cells from caspase-dependent mitochondrial apoptotic cell death. In this study we have investigated the role of GPR4 in 1-methyl-4-phenyl-1, 2, 3, 6-tetrahydropyridine (MPTP) treated mice model of Parkinson’s disease. Subchronic administration of MPTP in mice produces oxidative stress induced apoptotic cell death of dopaminergic neurons in the substantia nigra pars compacta (SNpc) and motor deficits. Treatment with NE52-QQ57, a selective antagonist of GPR4 reduced dopaminergic neuronal loss MPTP-intoxicated C57BL6/J mice and improved motor deficit and memory impairment. Co-treatment with NE52-QQ57 significantly decreases the protein level of proapoptotic marker (Bax), and increases the antiapoptotic marker (Bcl-2) in the SNpc and striatum tissue collected from the brain of MPTP inflicted mice. Further, MPTP induced activation of caspase 3 and cleavage of poly (ADP-ribose) polymerase (PARP) was significantly decreased in the SNpc and striatum tissue of NE52-QQ57 cotreated mice. Further mice receiving both MPTP and NE52-QQ57 mice showed significantly higher TH positive cells in the SNpc and striatum than MPTP treated mice alone. Moreover, NE52-QQ57 cotreatment improved the motor activity in the rotarod test and pole test and also improved spatial memory in Y maze test. Our findings suggest GPR4 as a potential therapeutic target for PD whereas the activation GPR4 is involved in the caspase mediated apoptotic cell death in SNpc and striatum of MPTP-intoxicated mice.

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Activation of α7-nAChRs Promotes the Clearance of α-Synuclein and Protects Against Apoptotic Cell Death Induced by Exogenous α-Synuclein Fibrils

Frontiers in Cell and Developmental Biology ◽

10.3389/fcell.2021.637319 ◽

2021 ◽

Vol 9 ◽

Author(s):

Jifeng Zhao ◽

Yun Li ◽

Yan Li ◽

Shi Xu ◽

Tingting Tao ◽

...

Keyword(s):

Cell Death ◽

Nicotinic Acetylcholine Receptors ◽

Acetylcholine Receptors ◽

Apoptotic Cell ◽

Cell Damage ◽

Neuroprotective Effect ◽

Cholinergic Neurons ◽

Apoptotic Cell Death ◽

Mammalian Brain ◽

Α7 Nachrs

Misfolding and abnormal aggregation of α-synuclein (αSyn) have been shown to increase the risk of developing Parkinson's disease (PD). Finding some way to reduce the aggregation of αSyn is particularly important for the treatment of PD. The main route in prion-like αSyn spreading is the cholinergic innervated vagus nervous system and central cholinergic neurons. Since the degenerative changes and death of cholinergic neurons also run through the pathological process of PD, we hypothesize an involvement of the cholinergic system in αSyn aggregation. The α7 nicotinic acetylcholine receptors (α7-nAChRs) are one of the most abundant nAChRs in the mammalian brain. Using nicotine and a selective α7-nAChRs agonist PNU-282987, we found a protective effect of α7-nAChRs on the cell damage induced by αSyn-PFF (preformed fibrils) through inhibiting apoptotic cell death. We further discovered an additive effect of α7-nAChRs on the clearance of αSyn in normal and αSyn stably transduced SH-SY5Y cells. Moreover, using α7-nAChRs knockout mice, we noticed that α7-nAChRs deficiency increased the deposition of αSyn and aggravated the loss of dopaminergic neurons in a chronic MPTP mouse model of PD. Our findings for the first time indicated that α7-nAChRs activation exhibited a neuroprotective effect on αSyn pathology and aggregation by promoting the clearance of αSyn.

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High Dose Magnesium Sulfate Exposure Induces Apoptotic Cell Death in the Developing Neonatal Mouse Brain

Neonatology ◽

10.1159/000201327 ◽

2009 ◽

Vol 96 (1) ◽

pp. 23-32 ◽

Cited By ~ 34

Author(s):

William H. Dribben ◽

Catherine E. Creeley ◽

Hai Hui Wang ◽

Derek J. Smith ◽

Nuri B. Farber ◽

...

Keyword(s):

Cell Death ◽

Magnesium Sulfate ◽

Mouse Brain ◽

Apoptotic Cell ◽

Apoptotic Cell Death ◽

Neonatal Mouse ◽

High Dose

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Abstract WP297: Moderate Alcohol Preconditioning Activates BKCa Channels to Protect Brain Damage-Induced by Cerebral Ischemic/Reperfusion

Stroke ◽

10.1161/str.48.suppl_1.wp297 ◽

2017 ◽

Vol 48 (suppl_1) ◽

Author(s):

Yi L Zhao ◽

An C Guo ◽

Yong J Wang ◽

Qun Wang

Keyword(s):

Cell Death ◽

Brain Damage ◽

Apoptotic Cell ◽

Infarct Volume ◽

Apoptotic Cell Death ◽

Bkca Channel ◽

Bkca Channels ◽

Ischemic Reperfusion ◽

Cerebral Ischemic ◽

Cerebral Ischemic Reperfusion

Objective: We hypothesis that moderate EtOH-PC activates BKCa channel to protect brain damage induced by focal cerebral I/R. This project will utilize focal cerebral ischemic/reperfusion (I/R) animal model to explore the function of BKCa channel in EtOH-PC protection in vivo levels by means of pharmacological intervention such as BKCa channel opener(NS11021)and blocker(Paxilline). Methods: The SD rat were randomly divided into the following six groups (n=10) : sham, I/R ,EtOH-PC+I/R, NS11021-PC+I/R, Paxilline+EtOH-PC+I/R, Paxilline+NS11021-PC+I/R. Both EtOH-PC and NS11021-PC (0.1mg/kg; ip) were induced 24h before I/R. The volume of 95% ethanol to be instilled (in μL) was calculated as follows: [body weight (g)х0.6] + 0.3. This volume of ethanol was mixed in 0.3mL of sterile distilled water just before administration to the animals by gavage. The Paxilline(2.5mg/kg; ip) was administered 10min before EtOH-PC and NS11021-PC.The right middle cerebral artery occlusion (MCAO) was produced by inversion of a 4-0-nylon filament. The filament was withdrawn 2h after onset of MCAO and then reperfused. Neurological deficits and infarct volume were measured 24 hours after I/R. Another 36 rats were randomly divided into 6 groups as above, 6 in each group. DWI were performed 2h after ischemic and T2WI MRI were performed 24h after ischemic/reperfusion to observe the infarct volume of brain and the penumbra volume of brain in each group. Then rats were killed and detected the apoptotic cell death and degeneration of neurons. Results: Compared to ischemic-reperfusion group, the neurological score (P < 0.01), the infarct volume of brain (P < 0.01), the infarct volume of ischemic penumbra(P < 0.01),the percentage of apoptotic cell death (P < 0.01) and the percentage of degenerative neurons (P < 0.01) were significantly decreased after ethanol and NS11021 preconditioning,while these changes were reversed by Paxilline(P < 0.05). Conclusion: Our results show that moderate alcohol preconditioning activates BKCa channels to protect brain damage induced by focal cerebral ischemic/reperfusion.

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Suppression of TRPM7 by carvacrol protects against injured spinal cord by inhibiting blood-spinal cord barrier disruption

10.21203/rs.3.rs-416918/v1 ◽

2021 ◽

Author(s):

Chan Sol Park ◽

Jee Youn Lee ◽

Hae Young Choi ◽

Bong Gun Ju ◽

Tae Young Yune

Keyword(s):

Spinal Cord ◽

Cell Death ◽

Transient Receptor Potential ◽

Apoptotic Cell ◽

Critical Role ◽

Apoptotic Cell Death ◽

Therapeutic Drug ◽

Transient Receptor Potential Melastatin ◽

Cord Injury ◽

Blood Spinal Cord Barrier

Abstract When the blood-spinal cord barrier (BSCB) is disrupted after a spinal cord injury (SCI), several pathophysiological cascades occur, including inflammation and apoptotic cell death of neurons and oligodendrocytes, resulting in permanent neurological deficits. Transient receptor potential melastatin 7 (TRPM7) is involved in the pathological processes in many neuronal diseases, including traumatic brain injury, amyotrophic lateral sclerosis, parkinsonism dementia, and Alzheimer’s disease. Furthermore, carvacrol (CAR), a TRPM7 inhibitor, is known to protect against SCI by reducing oxidative stress and inhibiting the endothelial nitric oxide synthase pathway. However, the functions of TRPM7 in the regulation of BSCB homeostasis after SCI have not been examined. Here, we demonstrated that TRPM7, a calcium-mediated non-selective divalent cation channel, plays a critical role after SCI in rat. Rats were contused at T9 and given CAR (50 mg/kg) via intraperitoneally immediately and 12 hours after SCI, and then given the same dose once a day for 7 days. TRPM7 was found to be up-regulated after SCI in both in vitro and in vivo studies, and it was expressed in blood vessels alongside neurons and oligodendrocytes. Additionally, CAR treatment suppressed BSCB disruption by inhibiting the loss of TJ proteins and preserved TJ integrity. CAR also reduced apoptotic cell death and improved functional recovery after SCI by preventing BSCB disruption caused by blood infiltration and inflammatory responses. Based on these findings, we propose that blocking the TRPM7 channel can inhibit the destruction of the BSCB and it is a potential target in therapeutic drug development for use in SCI.

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