Propofol increases expression of basic fibroblast growth factor after transient cerebral ischemia in rats

Veterinary medical care in rodent models of stroke: Pitfalls and refinements to balance quality of science and animal welfare

Rodent models of cerebral ischemia provide a valuable contribution to a better understanding of stroke pathophysiology, to validate diagnostic methods, and to enable testing of new treatments for ischemia-reperfusion damage and comorbidities. However, ethical concerns have led to increased attention to the welfare aspects of such models. Supportive therapies are an essential part of the overall animal care and use program and should be tailored to the experimental model being studied, the regulatory requirements, and research objectives to achieve high-quality preclinical studies and ethical research practices. On the other hand, the use of veterinary medical treatments in preclinical models of stroke must balance the needs of animal care and potential sources of bias in experimental results. This report provides a systematic review of the scientific literature covering the relevant period from years 1988 to September 2024, with the aim to investigating veterinary medical interventions useful to minimize suffering in rodent models of stroke without producing experimental bias. The research findings, consolidated from 181 selected studies, published from 1991 to 2023, indicate the feasibility of implementing personalized protocols of anesthesia, analgesics, antibiotics, and other supportive therapies in rodent models of stroke, while avoiding scientific interferences. These data fill a gap in current knowledge and could be of interest for an interdisciplinary audience working with rodent models of stroke, stimulating further refinements to safeguard both animal welfare and the validity of experimental findings, and may promote the culture of ethical conduct in various research fields and disciplines.

Edaravone dexborneol regulates γ-aminobutyric acid transaminase in rats with acute intracerebral hemorrhage

OBJECTIVES

Edaravone dexborneol is neuroprotective against ischemic stroke, with free radical-scavenging and anti-inflammatory effects, but its effects in hemorrhagic stroke remain unclear. We evaluated whether edaravone dexborneol has a neuroprotective effect in intracerebral hemorrhage, and its underlying mechanisms.

MATERIALS AND METHODS

Bioinformatics were used to predict the pathway of action of edaravone dexborneol. An intracerebral hemorrhage model was established using type IV collagenase in edaravone dexborneol, intracerebral hemorrhage, Sham, adeno-associated virus + edaravone dexborneol, and adeno-associated virus + intracerebral hemorrhage groups. The modified Neurological Severity Score was used to evaluate neurological function in rats. Brain water content was measured using the dry-wet weight method. Tumor necrosis factor-α, interleukin-1β, inducible nitric oxide synthase, and γ-aminobutyric acid levels were determined by enzyme-linked immunosorbent assay. The expression levels of neurofilament light chain and γ-aminobutyric acid transaminase were determined by western blot. Nissl staining was used to examine neuronal morphology. Cognitive behavior was evaluated using a small-animal treadmill.

RESULTS

Edaravone dexborneol alleviated neurological defects, improved cognitive function, and reduced cerebral edema, neuronal degeneration, and necrosis in rats with cerebral hemorrhage. The expression levels of neurofilament light chain, tumor necrosis factor-α, interleukin-1β, inducible nitric oxide synthase, and γ-aminobutyric acid were decreased, while γ-aminobutyric acid transaminase expression was up-regulated.

CONCLUSIONS

Edaravone dexborneol regulates γ-aminobutyric acid content by acting on the γ-aminobutyric acid transaminase signaling pathway, thus alleviating oxidative stress, neuroinflammation, neuronal degeneration, and death caused by excitatory toxic injury of neurons after intracerebral hemorrhage.

Calcitonin gene-related peptide: a potential protective agent in cerebral ischemia-reperfusion injury

Ischemic stroke is the most common type of cerebrovascular disease with high disability and mortality rates, which severely burdens patients, their families, and society. At present, thrombolytic therapy is mainly used for the treatment of ischemic strokes. Even though it can achieve a good effect, thrombolytic recanalization can cause reperfusion injury. Calcitonin gene-related peptide (CGRP) is a neuropeptide that plays a neuroprotective role in the process of ischemia-reperfusion injury. By combining with its specific receptors, CGRP can induce vasodilation of local cerebral ischemia by directly activating the cAMP-PKA pathway in vascular smooth muscle cells and by indirectly activating the NO-cGMP pathway in an endothelial cell-dependent manner,thus rapidly increasing ischemic local blood flow together with reperfusion. CGRP, as a key effector molecule of neurogenic inflammation, can reduce the activation of microglia, downregulates Th1 classical inflammation, and reduce the production of TNF-α, IL-2, and IFN-γ and the innate immune response of macrophages, leading to the reduction of inflammatory factors. CGRP can reduce the overexpression of the aquaporin-4 (AQP-4) protein and its mRNA in the cerebral ischemic junction, and play a role in reducing cerebral edema. CGRP can protect endothelial cells from angiotensin II by reducing the production of oxidants and protecting antioxidant defense. Furthermore, CGRP-upregulated eNOS can further induce VEGF expression, which then promotes the survival and angiogenesis of vascular endothelial cells. CGRP can also reduce apoptosis by promoting the expression of Bcl-2 and inhibiting the expression of caspase-3. These effects suggest that CGRP can reduce brain injury and repair damaged nerve function. In this review, we focused on the role of CGRP in cerebral ischemia-reperfusion injury.

Propofol Attenuates Inflammatory Damage via Inhibiting NLRP1-Casp1-Casp6 Signaling in Ischemic Brain Injury

Stroke is a common cerebrovascular disease. Inflammation-induced neuronal death is one of the key factors in stroke pathology. Propofol has been shown to ameliorate neuroinflammatory injury, but the exact mechanism of its neuroprotective role remains to be fully elucidated. In the present study, we found that inflammation was activated in ischemic cortical neurons, and the expression of nucleotide-binding domain, leucine-rich-repeat containing family, pyrin domain-containing 1 (NLRP1), NLRP3 inflammasome and effectors in primary cortical neurons increased. However, we found that propofol could inhibit the increased expression of NLRP1 and NLRP3 inflammasome induced by oxygen-glucose deprivation (OGD). Furthermore, the effector molecule caspase-1 (casp1) was revealed to be the downstream target of NLRP1 and propofol repressed the activation of caspase-1 via inhibiting NLRP1 in cortical neurons. Moreover, propofol inhibits caspase-6 activation in neurons through the NLRP1-caspase-1 pathway. Once the expression of caspase6 increases, propofol reduced its neuroprotective effect in OGD-treated cortical neurons. In the stroke middle cerebral artery occlusion (MCAO) model, infusion of caspase-6 inhibitors enhanced the protective effect of propofol on infarct size and neurological function. In conclusion, our results suggest that propofol plays a neuroprotective role in stroke by inhibiting the inflammatory pathway of NLRP1-caspase-1-caspase-6. Overall, these data suggest that propofol plays a key role in the inflammatory-dependent pathway after stroke, providing an important evidence for propofol as an effective strategy for neuroprotection in stroke.

Protective effect of hypoxia inducible factor-1α gene therapy using recombinant adenovirus in cerebral ischaemia-reperfusion injuries in rats

Context: Hypoxia-inducible factor-1α (HIF-1α)-induced genes can improve blood circulation.Objective: To investigate brain protective effect of recombinant adenovirus-mediated HIF-1α (AdHIF-1α) expression and its mechanism.Materials and methods: Male SD rats were used to establish focal cerebral ischaemia-reperfusion (CIR) injury models and randomly divided into normal, sham, CIR, Ad and AdHIF-1α groups. Ad or AdHIF-1α (10⁸ pfu/10 µL) were administered into lateral ventricle of rats in Ad and AdHIF-1α groups. Modified neurological severity score (mNSS), brain water content (BWC) and cerebral infarct volumes (CIVs) were analyzed, and HE staining was performed using the brain tissues. Furthermore, the expression of caspase-3 and HSP90 was analyzed using qRT-PCR and Western blotting.Results: Compared to CIR (mNSS, 8.52 ± 0.52; CIV, 0.22 ± 0.01) and Ad groups (mNSS, 8.83 ± 0.41; CIV, 0.22 ± 0.02), mNSS and CIV were significantly decreased in AdHIF-1α group (mNSS, 6.03 ± 0.61; CIV, 0.11 ± 0.01) at 72 h (p < 0.05). With prolonged reperfusion time (6 h to 72 h), BWC of all rats increased gradually, although the increase was markedly less in AdHIF-1α group (78.15 ± 0.16 to 87.01 ± 0.31) compared to that in CIR (78.77 ± 0.60 to 89.74 ± 0.34) and Ad groups (78.77 ± 0.35 to 89.71 ± 0.27) (p < 0.01). There were significantly greater pathological changes in the neurons in AdHIF-1α group at 72 h following CIR. Furthermore, expression of caspase-3 (p < 0.01) down-regulated and HSP90 up-regulated (p < 0.05) at mRNA and protein levels in AdHIF-1α group.Discussion and conclusions: HIF‑1α gene therapy is neuroprotective towards the CIR rat model. HIF-1α may be a candidate gene for the treatment of ischaemic brain injury.

Repression of long non-coding RNA MEG3 restores nerve growth and alleviates neurological impairment after cerebral ischemia-reperfusion injury in a rat model

OBJECTIVE

This study was performed to investigate effect of long non-coding RNA (lncRNA) MEG3 on nerve growth and neurological impairment in a rat model after cerebral ischemia-reperfusion injury (IRI) through the Wnt/β-catenin signaling pathway.

METHODS

Rat models of middle cerebral artery occlusion (MCAO) were established to stimulate an environment of cerebral IRI. The modeled rats were subjected to negative control (NC), MEG3, si-MEG3, classical Wnt pathway inhibitor DKK1 or classical Wnt pathway activator LiCl to validate the effect of MEG3 on neurological impairment and nerve growth. Neurological deficit scoring, fault-foot test and balance beam test were performed to assess neurological impairment. TTC staining, dry-wet weight method and Evan's blue (EB) staining were employed to determine infarct area, water content of brain tissues and blood-brain barrier (BBB) permeability, respectively. Neuronal apoptosis and necrosis were observed by TUNEL staining and Fluoro-Jade C staining. ELISA was adopted to identify levels of nerve growth factors to identify neurogenesis conditions, including brain derived neurotrophic factor (BDNF), nerve growth factor (NGF) and basic fibroblast growth factor (bFGF). Nissl staining was used to detect the survival of neurons in brain tissues of rats. Western blot analysis was used to detect the expression of key proteins in Wnt/β-catenin signaling pathway in brain tissues.

RESULTS

High expression of MEG3 was identified in rat models of MACAO, the brain tissues of which manifested obvious neurological impairment, increased infarct area, water content, BBB permeability, accelerated neuronal apoptosis and necrosis, increased surviving neurons, upregulated expression of key proteins in Wnt/β-catenin signaling pathway and elevated levels of BDNF, NGF and bFGF. With the treatment of si-MEG3, the MEG3 expression was reduced; whereby, modeled rats showed ameliorated neurological impairment, reduced infarct area, water content, BBB permeability, neuronal apoptosis and necrosis and significantly enhanced neurogenesis. The treatment of MEG3 exhibited an opposite trend. After treatment with DKK1, the effect of si-MEG3 was reversed. After treatment with LiCl, the effect of MEG3 was reversed.

CONCLUSION

Based on the findings of this study, down-regulation of lncRNA MEG3 expression enhanced nerve growth and alleviated neurological impairment of rats after cerebral IRI through the activation of the Wnt/β-catenin signaling pathway.

Intranasal Calcitonin Gene-Related Peptide Protects Against Focal Cerebral Ischemic Injury in Rats Through the Wnt/β-Catenin Pathway

Background

Intranasal calcitonin gene-related peptide (CGRP) delivery offers a noninvasive method of bypassing the blood-brain barrier for the delivery of CGRP to the brain. Here, we first reported the therapeutic benefits of intranasal CGRP delivery in rats following middle cerebral artery occlusion (MCAO).

Material/Methods

Real-time quantitative polymerase chain reaction (RT-qPCR) assay, enzyme-linked immunosorbent assay (ELISA), rat MCAO model, TTC (2, 3, 5-triphenyltetrazolium chloride) staining, hematoxylin and eosin (H & E) staining, Morris water maze test, TUNEL assay, immunofluorescence, and western blot assay were used to investigate the role of CGRP in rats. Cell Counting Kit-8 assay, colony formation assay, cell cycle assay, apoptosis assay, western blot assay, and TOP/FOP assay were used to investigate the role of CGRP in normal human astrocytes (NHA) cells.

Results

The CGRP-MCAO-NDDS (nasal drug delivery system) group showed a significant reduction in the infarct volume and improvement in neurologic deficit tests of motor, sensory, reflex and vestibulo-motor functions compared to those rats in the CGRP-MCAO-IV group. CGRP markedly inhibited apoptosis and increased the expression of vascular endothelial growth factor (VEGF) and bFGF and decreased the expression of GAP43 in the cortex of MCAO rats. CGRP promoted cell proliferation and cell cycle process and inhibited cell apoptosis through the Wnt/β-catenin pathway in NHA cells.

Conclusions

This noninvasive, simple, and cost-effective method is a potential treatment strategy for focal cerebral ischemic injury.

Hypoxia stimulates neural stem cell proliferation by increasing HIF‑1α expression and activating Wnt/β-catenin signaling

Evidence indicates that after brain injury, neurogenesis is enhanced in regions such as hippocampus, striatum, and cortex. To study the role of hypoxia-inducible factor-1 (HIF‑1α) and Wnt signaling in cerebral ischemia/hypoxia-induced proliferation of neural stem cells (NSCs), we investigated the proliferation of NSCs, expression of HIF‑1α, and activation of Wnt signaling under conditions of pathologic hypoxia in vitro. NSCs were isolated from 30-day-old Sprague-Dawley rats and subjected to 0.3% oxygen in a microaerophilic incubation system. Cell proliferation was evaluated by measuring the diameter of neurospheres and by bromodeoxyuridine incorporation assays. Real-time quantitative PCR and Western blotting were used to detect mRNA and protein levels of HIF-1α, β-catenin, and cyclin D1 in the NSCs. The results showed that hypoxia increased NSC proliferation and the levels of HIF-1α, β‑catenin, and cyclin D1 (p &lt; 0.05). Blockade of the Wnt signaling pathway decreased hypoxia-induced NSC proliferation, whereas activation of this pathway increased hypoxia-induced NSC proliferation (p &lt; 0.05). Knockdown of HIF-1α with HIF-1α siRNA decreased β‑catenin nuclear translocation and cyclin D1 expression, and inhibited proliferation of NSCs (p &lt; 0.05). These findings indicate that pathologic hypoxia stimulates NSC proliferation by increasing expression of HIF-1α and activating the Wnt/β-catenin signaling pathway. The data suggest that Wnt/β-catenin signaling may play a key role in NSC proliferation under conditions of pathologic hypoxia.

Suppression of Basic Fibroblast Growth Factor Expression by Antisense Oligonucleotides Inhibits Neural Stem Cell Proliferation and Differentiation in Rat models With Focal Cerebral Infarction

This study is designed to investigate the role of basic fibroblast growth factor (bFGF) antisense oligonucleotide (ASODN) on the proliferation and differentiation of neural stem cells (NSCs) in rat models with focal cerebral infarction (CI). Seventy-five Sprague-Dawlay (SD) rats were randomly divided into the control, sham, middle cerebral artery occlusion (MCAO), MCAO + nonsense oligonucleotide (NODN), and MCAO + ASODN groups. Proliferation and differentiation of NSCs were detected by bromodeoxyuridine (BrdU) and immunofluorescence staining, respectively. ELISA was performed to detect the expressions of endogenous factors that include insulin-like growth factor 1 (IGF-1), glial cell line derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), transforming growth factor-α1 (TGF-α1), bFGF, and nerve growth factor (NGF). Results show significant neurological deficits and focal CI in the MCAO and MCAO + NODN groups. An obvious increase of NSC proliferation, reactive proliferation of astrocytes in CI areas, differentiation of newly proliferated NSCs into mature neuronal cells, and expressions of endogenous growth factors exhibited in the MCAO, MCAO + NODN and MCAO + ASODN groups. Compared to the MCAO and MACO + NODN groups, the MCAO + ASODN group showed a significant decrease NSC proliferation and differentiation in CI areas as well as decrease expressions of endogenous growth factors. These findings may offer insight to help us understand more as to how bFGF ASODN can effectively suppress the proliferation and differentiation of NSCs. These findings are expected to help contribute to research for new targets in the treatment of focal CI. J. Cell. Biochem. 118: 3875-3882, 2017. © 2017 Wiley Periodicals, Inc.

3,4-oxo-isopropylidene-shikimic acid inhibits cerebral ischemia-induced oxidative stress and neuronal apoptosis in rats

BACKGROUND

To investigate the potential protective effects of 3,4-oxo-isopropylidene-shikimic acid (ISA) on brain ischemic injury in rats.

METHODS

Cell Counting Kit-8, flow cytometry, and TUNEL were used to evaluate the cell viability and the apoptosis rate in vitro and in situ. Reactive oxygen species generation was determined by DCFH-DA assay. qPCR and Western blot were used to test the molecular mechanisms related to the anti-apoptosis effects.

RESULT

Protective effect of pre-conditioning of ISA on the brain injury caused by ischemia was observed. ISA treatment showed anti-apoptosis effects on isolated primary astrocytes and neurons. ROS generation was also significantly scavenged by treatment of ISA. The treatment with ISA protected astrocytes from hypoxic condition-induced apoptosis and ischemic injury. The underlying mechanisms revealed by qPCR and WB showed that the level of mRNA and protein expression of Bax, Bcl-2, and caspase-3 were significantly down-regulated by ISA treatment (P < 0.05). Pre-conditioning with ISA is beneficial in reducing the neuronal damage caused by brain ischemia.

CONCLUSION

Treatment with ISA reduces apoptosis and ROS over-generation caused by ischemic injury. Pre-conditioning with ISA resulted in significantly protective effects on brain under ischemic condition.

The Dose of Intravenously Transplanted Bone Marrow Stromal Cells Determines the Therapeutic Effect on Vascular Remodeling in a Rat Model of Ischemic Stroke

The therapeutic benefits of bone marrow-derived mesenchymal stem cell (BM-MSC) transplantation for ischemic stroke have been extensively demonstrated. However, studies on the optimal cell dose for intravenous administration are still limited. This study aimed to determine an appropriate cell dose for BM-MSC intravenous transplantation and to investigate the effect of cell dose on vascular remodeling in a rat model of ischemic stroke. BM-MSCs at doses of 5104 (low-dose group), 5105 (medium-dose group), and 2106 (high-dose group) were intravenously injected into rats at 72 h after ischemia. The therapeutic efficacy of BM-MSCs was evaluated by measuring infarct volume, vascular diameters, capillary area in the peri-infarct zone, level of basic fibroblast growth factor (bFGF) in the peri-infarct zone, and serum vascular endothelial growth factor (VEGF) level at 7 days after ischemia. Compared with the low-dose and control groups, medium-dose and high-dose BM-MSC transplantation significantly reduced the volume of the infarct area, enlarged the diameters of pial vessels and the basilar artery, and increased the capillary area in the peri-infarct zone of the cerebral cortex. Furthermore, transplanted BM-MSCs elevated the expressions of bFGF in the peri-infarct zone and the serum VEGF level. Administration of 5105 BM-MSCs is an appropriate cell dose for ischemic stroke therapy in rats. These findings may be helpful for designing future clinical trials.

The effect of propofol on the expression of rabbit ischemia reperfusion injury-related proteins

To investigate the effect of propofol on the expression of rabbit ischemia-reperfusion injury-related proteins and the mechanism involved. Thirty healthy adult New Zealand rabbit were selected. After establishment of liver I/R model, the rabbits were divided into group A (sham operation group), group B (control group using saline), and group C (propofol group) with ten rabbits in each group. The total protein concentration, differentially expressed protein spots and the difference of apoptotic proteins expression levels among the three groups were compared. The total protein concentrations in group A, B, and C were 0.778, 0.835, and 0.765 μg/μl, respectively, and the protein concentration in group B was significantly higher than group A and C (p < 0.05), with no significant difference between group A and C (p > 0.05); results analyzed by PDQuest software showed that the average number of protein spots and matching ratio had no significant difference among the three groups (p > 0.05); MALDI-TOF-MS mass spectrometry identified 16 differentially expressed protein spots; the numbers of Caspase-3 positive cells in group B and C were significantly higher than those in group A, and the numbers of Bcl-2 and Bax positive cells in group B and C were significantly lower than those in group A (p < 0.05); the number of Capase-3 positive cells in group C was significantly higher than those in group B, and the number of Bcl-2 positive cells in group C was significantly lower than those in group B (p < 0.05). The numbers of Bax positive cells had no significant difference between group B and C (p > 0.05); densities of Caspase-3, Bcl-2 and Bax in group B and C were significantly higher than those in group A (p < 0.05); Western blotting results from the comparison of the number of positive cells between group B and C was in accordance to the result obtained from immunohistochemistry. After I/R injury in rabbit, there was deregulation of various proteins such as Caspase-3, Bcl-2 and Bax, which was an important factor contributing to liver injury even systematic disease. Propofol could regulate the expression of I/R injury-related proteins and inhibit the attack of free radical to liver, having a remarkable advantage in preventing I/R injury and controlling the development of I/R injury. This study provides an effective theoretical basis for the prevention and treatment of I/R injury.

The reaction of cerebral cortex to a nearby lesion: damage, survival, self-protection

A needlestick injury to cerebral cortex causes immediate damage along the track of the needle (haemorrhage, cell death) and sequelae (the formation of amyloid-positive plaques, extracellular deposits of hyperphosphorylated tau protein, microglial proliferation, astrogliosis) that are long lasting, and mimic the neuropathology associated with Alzheimer's disease. We report here that the same injury also elicits a distinctive response in the cortex flanking (up to 1mm from) the direct injury. Needlestick injury was made in the neo- and hippocampal cortex of young (3 months) healthy Sprague-Dawley rats. After survival times of up to 7d, the response of the cortex was assessed with histology, immunohistochemistry and stereology. Uptake of FluoroJade B at 1d survival and labelling for 4-hydroxynonenal (4-HNE) gave measures of membrane damage; labelling for 8-hydroxy-2'-deoxyguanosine (8-OHDG) gave a measure of DNA damage, and labelling with the AT8 antibody gave a measure of the hyperphosphorylation of tau. Two probes, for neuroglobin and basic fibroblast growth factor (FGF-2), gave measures of a self-protective response in the tissue. Results indicate that neurones in the flanking region are damaged by the nearby lesion, and within 1d upregulate self-protective mechanisms. Over the next 6d survival, evidence of neuronal damage reduces markedly. In summary, cells in the region flanking a lesion are stressed by the lesion, and react to the stress with a self-protective response, which prevents their death. This response may be an important, previously unrecognised feature of brain tissue close to a focus of stress, such as a microhaemorrhage.

Propofol protects against focal cerebral ischemia via inhibition of microglia-mediated proinflammatory cytokines in a rat model of experimental stroke

Ischemic stroke induces microglial activation and release of proinflammatory cytokines, contributing to the expansion of brain injury and poor clinical outcome. Propofol has been shown to ameliorate neuronal injury in a number of experimental studies, but the precise mechanisms involved in its neuroprotective effects remain unclear. We tested the hypothesis that propofol confers neuroprotection against focal ischemia by inhibiting microglia-mediated inflammatory response in a rat model of ischemic stroke. Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for 2 h followed by 24 h of reperfusion. Propofol (50 mg/kg/h) or vehicle was infused intravenously at the onset of reperfusion for 30 minutes. In vehicle-treated rats, MCAO resulted in significant cerebral infarction, higher neurological deficit scores and decreased time on the rotarod compared with sham-operated rats. Propofol treatment reduced infarct volume and improved the neurological functions. In addition, molecular studies demonstrated that mRNA expression of microglial marker Cd68 and Emr1 was significantly increased, and mRNA and protein expressions of proinflammatory cytokines tumor necrosis factor-α, interleukin-1β and interleukin-6 were augmented in the peri-infarct cortical regions of vehicle-treated rats 24 h after MCAO. Immunohistochemical study revealed that number of total microglia and proportion of activated microglia in the peri-infarct cortical regions were markedly elevated. All of these findings were ameliorated in propofol-treated rats. Furthermore, vehicle-treated rats had higher plasma levels of interleukin-6 and C-reactive protein 24 h after MCAO, which were decreased after treatment with propofol. These results suggest that propofol protects against focal cerebral ischemia via inhibition of microglia-mediated proinflammatory cytokines. Propofol may be a promising therapeutic agent for the treatment of ischemic stroke and other neurodegenerative diseases associated with microglial activation.

Probenecid protects against transient focal cerebral ischemic injury by inhibiting HMGB1 release and attenuating AQP4 expression in mice

Stroke results in inflammation, brain edema, and neuronal death. However, effective neuroprotectants are not available. Recent studies have shown that high mobility group box-1 (HMGB1), a proinflammatory cytokine, contributes to ischemic brain injury. Aquaporin 4 (AQP4), a water channel protein, is considered to play a pivotal role in ischemia-induced brain edema. More recently, studies have shown that pannexin 1 channels are involved in cerebral ischemic injury and the cellular inflammatory response. Here, we examined whether the pannexin 1 channel inhibitor probenecid could reduce focal ischemic brain injury by inhibiting cerebral inflammation and edema. Transient focal ischemia was induced in C57BL/6J mice by middle cerebral artery occlusion (MCAO) for 1 h. Infarct volume, neurological score and cerebral water content were evaluated 48 h after MCAO. Immunostaining, western blot analysis and ELISA were used to assess the effects of probenecid on the cellular inflammatory response, HMGB1 release and AQP4 expression. Administration of probenecid reduced infarct size, decreased cerebral water content, inhibited neuronal death, and reduced inflammation in the brain 48 h after stroke. In addition, HMGB1 release from neurons was significantly diminished and serum HMGB1 levels were substantially reduced following probenecid treatment. Moreover, AQP4 protein expression was downregulated in the cortical penumbra following post-stroke treatment with probenecid. These results suggest that probenecid, a powerful pannexin 1 channel inhibitor, protects against ischemic brain injury by inhibiting cerebral inflammation and edema.