Research into how carvacrol and metformin affect several human proteins in a hyperglycemic condition: A comparative study in silico and in vitro.

Carvacrol (CV) is an organic compound found in the essential oils of many aromatic herbs. It is nearly unfeasible to analyze all the current human proteins for a query ligand using in vitro and in vivo methods. This study aimed to clarify whether CV possesses an anti-diabetic feature via Docking-based inverse docking and molecular dynamic (MD) simulation and in vitro characterization against a set of novel human protein targets. Herein, the best poses of CV docking simulations according to binding energy ranged from -7.9 to -3.5 (kcal/mol). After pathway analysis of the protein list through GeneMANIA and WebGestalt, eight interacting proteins (DPP4, FBP1, GCK, HSD11ß1, INSR, PYGL, PPARA, and PPARG) with CV were determined, and these proteins exhibited stable structures during the MD process with CV. In vitro application, statistically significant results were achieved only in combined doses with CV or metformin. Considering all these findings, PPARG and INSR, among these target proteins of CV, are FDA-approved targets for treating diabetes. Therefore, CV may be on its way to becoming a promising therapeutic compound for treating Diabetes Mellitus (DM). Our outcomes expose formerly unexplored potential target human proteins, whose association with diabetic disorders might guide new potential treatments for DM.

Kaempferol treatment ameliorates memory impairments in STZ­induced neurodegeneration by acting on reelin signaling.

Many treatment initiatives, like herbal products and their active ingredients, aim to alleviate neurodegeneration to increase cognitive functions. Kaempferol may be a candidate molecule for treating neurodegeneration because of its antioxidant effects. In the present study, we examined the molecular changes associated with kaempferol's memory­enhancing effects on streptozotocin (STZ)­induced neurodegeneration. After intracerebroventricular STZ injection in Long­Evans male rats, intraperitoneal kaempferol was administered for 12 days. The Morris water maze (MWM) was used to measure learning and memory performance in the rats, and proteins related to memory formation were investigated in the hippocampi with western blotting. Kaempferol improved learning performance and memory decline in STZ­treated rats. At the molecular level, STZ­induced neurodegeneration resulted in a decrease in the expression of GAD67, reelin, and phosphorylated­NMDAR. However, kaempferol treatment ameliorated these changes by enhancing their levels similar to the controls. While neither STZ injection nor kaempferol treatment produced any significant change in phosphorylated­CAMKII levels, they increased the expression of klotho and prealbumin. These results show that kaempferol has positive effects on memory loss, affecting synaptic plasticity by ameliorating both the levels and activity of memory­relevant molecules through reelin signaling. In summary, this study provides a guide to future studies by examining in detail the healing effect of kaempferol as a candidate molecule in the treatment of neurodegeneration, such as that observed in Alzheimer's disease.

Age-Associated Resilience Against Ischemic Injury in Mice Exposed to Transient Middle Cerebral Artery Occlusion.

Ischemic stroke is the leading cause of death and disability. Although stroke mainly affects aged individuals, animal research is mostly one on young rodents. Here, we examined the development of ischemic injury in young (9-12-week-old) and adult (72-week-old) C57BL/6 and BALB/c mice exposed to 30 min of intraluminal middle cerebral artery occlusion (MCAo). Post-ischemic reperfusion did not differ between young and adult mice. Ischemic injury assessed by infarct area and blood-brain barrier (BBB) integrity assessed by IgG extravasation analysis was smaller in adult compared with young mice. Microvascular viability and neuronal survival assessed by CD31 and NeuN immunohistochemistry were higher in adult than young mice. Tissue protection was associated with stronger activation of cell survival pathways in adult than young mice. Microglial/macrophage accumulation and activation assessed by F4/80 immunohistochemistry were more restricted in adult than young mice, and pro- and anti-inflammatory cytokine and chemokine responses were reduced by aging. By means of liquid chromatography-mass spectrometry, we identified a hitherto unknown proteome profile comprising the upregulation of glycogen degradation-related pathways and the downregulation of mitochondrial dysfunction-related pathways, which distinguished post-ischemic responses of the aged compared with the young brain. Our study suggests that aging increases the brain's resilience against ischemic injury.

Dual action of exosomes derived from in vitro Aß toxicity model: The role of age for pathological response.

Exosomes released from different cell types of the central nervous system play an essential role in the pathogenesis of Alzheimer's disease (AD). In this study, we aimed to create an animal model by injecting exosomes that carry AD markers into the brain to shed light on the mechanism behind Alzheimer's pathology. Exosomes obtained from mouse Neuro2A, to which Aß toxicity model applied, were used as a mediator to build an AD phenotype. For this purpose, exosomes were administered into hippocampal CA3 region of mice with different ages. Firstly, the possible role of exosomes on brain volume was analyzed. Then, neurons and astrocytes were evaluated for survival. In addition, the progenitor cells' differentiation capacity was investigated via BrdU staining. AKT signaling pathway components were examined to detect the molecular mechanisms behind the exosomal function. We found different responses in different age groups. Expression of APP upregulated only in young animals upon delivery of Aß-exosomes. Interestingly, young animals represented increased numbers of neurons in the hippocampus, and neurogenesis was found to be restricted after Aß-Ex injections. However, in relation to exosome administration, the glial intensity increased in aged animals. Lastly, phosphorylation of survival kinase AKT was downregulated due to the presence of Aß in both young and old animals. The findings reveal that the exosomes from an in vitro Aß toxicity model may induce different responses in an age-dependent manner. This study is the first to report the relationship between exosomal function and aging by evaluating the key molecules.

Delayed Therapeutic Administration of Melatonin Enhances Neuronal Survival Through AKT and MAPK Signaling Pathways Following Focal Brain Ischemia in Mice.

Melatonin has a role in the cell survival signaling pathways as a candidate for secondary stroke prevention. Therefore, in the present study, the coordination of ipsilateral and contralateral hemispheres to evaluate delayed post-acute effect of melatonin was examined on recovery of the cell survival and apoptosis after stroke. Melatonin was administered (4 mg/kg/day) intraperitoneally for 45 days, starting 3 days after 30 min of middle cerebral artery occlusion. The genes and proteins related to the cell survival and apoptosis were investigated by immunofluorescence, western blotting, and RT-PCR techniques after behavioral experiments. Melatonin produced delayed neurological recovery by improving motor coordination on grip strength and rotarod tests. This neurological recovery was also reflected by high level of NeuN positive cells and low level of TUNEL-positive cells suggesting enhanced neuronal survival and reduced apoptosis at the fifty-fifth day of stroke. The increase of NGF, Nrp1, c-jun; activation of AKT; and dephosphorylation of ERK and JNK at the fifty-fifth day showed that cell survival and apoptosis signaling molecules compete to contribute to the remodeling of brain. Furthermore, an increase in the CREB and Atf-1 expressions suggested the melatonin's strong reformative effect on neuronal regeneration. The contralateral hemisphere was more active at the latter stages of the molecular and functional regeneration which provides a further proof of principle about melatonin's action on the promotion of brain plasticity and recovery after stroke.

Striatal dopaminergic neurons as a potential target for GDNF based ischemic stroke therapy.

BACKGROUND: Glial cell-line-derived neurotrophic factor (GDNF) is a well-known regulatory neurotrophic factor on dopaminergic neurons. Several pathologies have been documented so far in case of any impairment in the dopaminergic system. This study aimed to investigate the potential protective role of lentiviral GNDF delivery on the small population of tyrosine hydroxylase (TH) positive dopamine producing striatal neurons after ischemic stroke. METHODS: Fourteen C57BL/6J male mice (8-10 weeks) were intracerebrally treated with lentiviral GDNF (Lv-GDNF) or vehicle. Ten days after injections, cerebral ischemia was induced by blockage of the middle cerebral artery. Animals were terminated 72 h after ischemia, and their brains were taken for histological and molecular investigations. Following confirmation of GDNF overexpression, TH immunostaining and immunoblotting were used to evaluate the role of GDNF on dopaminergic neurons. Next, Fluro Jade C staining was implemented to examine the degree of neuronal degeneration at the damaged parenchyma. RESULTS: Neither the amount of TH positive dopaminergic neurons nor the expression of TH changed in the Lv-GDNF treated animals comparing to the vehicle group. On the other hand, GDNF exposure caused a significant increase in the expression of Nurr1, an essential transcription factor for dopaminergic neurons and Gap43, growth and plasticity promoting protein, in the ischemic striatum. Treatment with Lv-GDNF gave rise to a significant reduction in the number of degenerated neurons. Finally, enhanced GDNF expression also induced expression of an important stress-related transcription factor NF-κB as well as the nitric oxide synthase enzymes iNOS and nNOS in the contralesional hemisphere.

Astragalus membranaceus treatment combined with caloric restriction may enhance genesis factors and decrease apoptosis in the hippocampus of rats.

Humans have been searching for ways of extending life span, and possible underlying molecular mechanisms behind it for many years. Traditional plants and their extracts are good candidates for finding anti-aging strategies. In addition to its usage in a variety of medical treatments such as inflammation, neural diseases and cancer, Astragalus membranaceus was used to extend lifespan of C. elegans. Therefore, we aimed to show the molecular mechanisms of the possible anti-aging effects of combination of A. membranaceus and caloric restriction. Herein, Wistar rats (n = 24) were divided into Control, A. membranaceus (A) (25 mg/kg A), Caloric restriction (CR) (20% restricted-diet), and CR+A (25 mg/kg A + 20% CR diet) groups. After 18 weeks, behavioral tests were applied to observe alterations on cognitive functions. After animals were decapitated, their hippocampi and livers were dissected for molecular analysis and telomerase activity. Eventually, CR increased learning performances of rats with an increase in the telomerase activity when combined with astragalus. There was a negative correlation between learning and apoptosis parameters. In the CR group, the apoptosis rate increased, and the pyramidal neuron numbers decreased which were reached to control levels with A treatment. The CR+A treatment significantly increased the BDNF level. The A also significantly increased GDNF level independent from CR. In the combination group, the neurogenesis and angiogenesis markers increased with an increase in the anti-senescence protein klotho land a decrease in the apoptosis. In conclusion, combination of caloric restriction with A. membranaceus would become a promising strategy for healthy cognitive aging.

Inflammatory Cytokines are in Action: Brain Plasticity and Recovery after Brain Ischemia Due to Delayed Melatonin Administration.

OBJECTIVES: Post-ischemic inflammation leads to apoptosis as an indirect cause of functional disabilities after the stroke. Melatonin may be a good candidate for the stroke recovery because of its anti-inflammatory effects. Therefore, we investigated the effect of melatonin on inflammation in the functional recovery of brain by evaluating ipsilesional and contralesional alterations. MATERIALS AND METHODS: Melatonin (4 mg/kg/day) was intraperitoneally administered into the mice from the 3rd to the 55th day of the post-ischemia after 30 min of middle cerebral artery occlusion. RESULTS: Melatonin produced a functional recovery by reducing the emigration of the circulatory leukocytes and the local microglial activation within the ischemic brain. Overall, the expression of the inflammation-related genes reduced upon melatonin treatment in the ischemic hemisphere. On the other hand, the expression level of the inflammatory cytokine genes raised in the contralateral hemisphere at the 55th day of the post-ischemia. Furthermore, melatonin triggers an increase in the iNOS expression and a decrease in the nNOS expression in the ipsilateral hemisphere at the earlier times in the post-ischemic recovery. At the 55th day of the post-ischemic recovery, melatonin administration enhanced the eNOS and nNOS protein expressions. CONCLUSIONS: The present molecular, biological, and histological data have revealed broad anti-inflammatory effects of melatonin in both hemispheres with distinct temporal and spatial patterns at different phases of post-stroke recovery. These outcomes also established that melatonin act recruitment of contralesional rather than of ipsilesional.

Thymoquinone administration ameliorates Alzheimer's disease-like phenotype by promoting cell survival in the hippocampus of amyloid beta1-42 infused rat model.

BACKGROUND: Thymoquinone (TQ), a biologically active ingredient of Nigella sativa, has anti-inflammatory, anti-oxidative and neuroprotective properties. Therefore, it could be a good candidate in the recovery of Alzheimer`s disease (AD) pathology rather than current symptomatic reliefs. PURPOSE: In the present study, we examined the molecular healing effects of TQ in amyloid beta 1-42 (Aß1-42) peptide-infused AD rat hippocampus. STUDY DESIGN: A micro-osmotic pump containing aggregated Aß1-42 was cannulated into the hippocampus of adult female rats. After two weeks infusion, the dose of TQ (10 mg/kg or 20 mg/kg) was determined according to the HPLC results of cerebrospinal fluid and TQ was given to rats intragastrically for 15 days. METHODS: The memory performance of rats was determined by Morris water maze test. Afterwards, the acetylcholinesterase (AChE) level were measured by ELISA. Histopathological examinations of hippocampal tissue were performed for cell survival by Nissl staining, for detection of amyloid plaque deposits by Congo red staining and for determination of degenerating neurons by Fluoro Jade C staining. MicroRNA/mRNA levels and protein expressions of AD-related genes and proteins were analyzed by Real-Time Polymerase Chain Reaction and Western Blotting, respectively. RESULTS: Administration of TQ enhanced the memory performance of Aß1-42 infused rats and it also ameliorated the neuronal loss in the cornu ammonis (CA1), but not in the dentate gyrus (DG). In addition, TQ treatment decreased the fibril deposition whose accumulation was significantly higher in the Aß1-42-infused animals compared to that of the control group. The expression profiles of mir29c and Bax which significantly upregulated in the Aß1-42-infused animals were attenuated by TQ. Furthermore, administration of TQ decreased the expressions of Aß, phosphorylated-tau, and BACE-1 proteins. There was no significant therapeutic effect of TQ on the AKT/GSK3ß or MAPK signaling pathways which were affected due to Aß1-42 infusion. CONCLUSION: TQ has the capacity to recover the neuropathology by removing Aß plaques and by restoring neuron viability. All might have established the molecular basement of the consolidation in the memory observed by means of TQ treatment.

Fetal alcohol and maternal stress modify the expression of proteins controlling postnatal development of the male rat hippocampus.

Background: Developing brains can partially get over prenatal alcohol exposure-related detrimental conditions by activating some mechanisms involved in survival. Objectives: This study aimed to shed light on the molecular correlates of compensatory mechanisms by examining temporal profiles in the expression of proteins controlling postnatal development in the rat hippocampus prenatally exposed to intubation stress/ethanol. Methods: Male pups were randomly assigned to age subgroups (n = 21/age) which were sacrificed on postnatal day (PD)1, PD10, PD30, and PD60. Ethanol (6 g/kg/day) were intragastrically intubated to the dams throughout 7-21 gestation days. The expression of neurogenesis and angiogenesis markers, extracellular matrix proteins, and growth-promoting ligands were examined by western blot. Results: The most rapid increase in the index of neuronal maturation was noted between PD10-PD30 (p < .05). Prenatal stress caused a decrease of neurogenesis markers at birth and an increase of their expressions at PD10 and PD30 to reach control levels (p < .001). The impact of fetal-alcohol was observed as a decrease in the expression of synaptic plasticity protein versican at birth (p < .001), an increase in the synaptic repulsion protein ephrin-B2 at PD10 (p < .001), and a decrease in the maturation of BDNF at PD30 (p < .001) with a decrease in the mature neuron markers at PD30 (p < .001) and PD60 (p = .005) which were compensated with upregulation of angiogenesis and increasing brevican expression, a neuronal maturation protein (p < .001). Conclusion: These data provide in vivo evidence for the potential therapeutic factors related to neurogenesis, angiogenesis, and neurite remodeling which may tolerate the alcohol/stress dependent teratogenicity in the developing hippocampus.

Lentivirally administered glial cell line-derived neurotrophic factor promotes post-ischemic neurological recovery, brain remodeling and contralesional pyramidal tract plasticity by regulating axonal growth inhibitors and guidance proteins.

Owing to its potent longterm neuroprotective and neurorestorative properties, glial cell line-derived neurotrophic factor (GDNF) is currently studied in neurodegenerative disease clinical trials. However, little is known about the longterm effect of GDNF on neurological recovery, brain remodeling and neuroplasticity in the post-acute phase of ischemic stroke. In a comprehensive set of experiments, we examined the effects of lentiviral GDNF administration after ischemic stroke. GDNF reduced neurological deficits, neuronal injury, blood-brain barrier permeability in the acute phase in mice. As compared with control, enhanced motor-coordination and spontaneous locomotor activity were noted in GDNF-treated mice, which were associated with increased microvascular remodeling, increased neurogenesis and reduced glial scar formation in the peri-infarct tissue. We observed reduced brain atrophy and increased plasticity of contralesional pyramidal tract axons that crossed the midline in order to innervate denervated neurons in the ipsilesional red and facial nuclei. Contralesional axonal plasticity by GDNF was associated with decreased abundance of the axonal growth inhibitors brevican and versican in contralesional and ipsilesional brain tissue, reduced abundance of the growth repulsive guidance molecule ephrin b1 in contralesional brain tissue, increased abundance of the midline growth repulsive protein Slit1 in contralesional brain tissue and reduced abundance of Slit1's receptor Robo2 in ipsilesional brain tissue. These data indicate that GDNF potently induces longterm neurological recovery, peri-infarct brain remodeling and contralesional neuroplasticity, which are associated with the fine-tuned regulation of axonal growth inhibitors and guidance molecules that facilitate the growth of contralesional corticofugal axons in the direction to the ipsilesional hemisphere.

Unraveling the Role of Inwardly Rectifying Potassium Channels in the Hippocampus of an Aß(1-42)-Infused Rat Model of Alzheimer's Disease.

Alzheimer's disease (AD) is a progressive neurodegenerative disorder with a complex etiology and characterized by cognitive deficits and memory loss. The pathogenesis of AD is not yet completely elucidated, and no curative treatment is currently available. Inwardly rectifying potassium (Kir) channels are important for playing a key role in maintaining the resting membrane potential and controlling cell excitability, being largely expressed in both excitable and non-excitable tissues, including neurons. Accordingly, the aim of the study is to investigate the role of neuronal Kir channels in AD pathophysiology. The mRNA and protein levels of neuronal Kir2.1, Kir3.1, and Kir6.2 were evaluated by real-time PCR and Western blot analysis from the hippocampus of an amyloid-ß(Aß)(1-42)-infused rat model of AD. Extracellular deposition of Aß was confirmed by both histological Congo red staining and immunofluorescence analysis. Significant decreased mRNA and protein levels of Kir2.1 and Kir6.2 channels were observed in the rat model of AD, whereas no differences were found in Kir3.1 channel levels as compared with controls. Our results provide in vivo evidence that Aß can modulate the expression of these channels, which may represent novel potential therapeutic targets in the treatment of AD.

Prenatal ethanol intoxication and maternal intubation stress alter cell survival and apoptosis in the postnatal development of rat hippocampus.

It is well known that the fetal ethanol exposure and prenatal stress may have adverse effects on brain development. Interestingly, some morphological and functional recovery from their teratogenic effects that take place during brain maturation. However, mechanisms that underlie this recovery are not fully elucidated. The aim of this study was to examine whether the postnatal attenuation of fetal alcohol - and maternal stress­induced morphological and functional deficits correlates with compensatory changes in the expression/activation of the brain proteins involved in inflammation, cell survival and apoptosis. In this project, we investigated the hippocampus which belongs to the brain regions most susceptible to the adverse effects of prenatal ethanol exposure. Pregnant rat dams were administered ethanol (A) or isocaloric glucose solution (IC) by a gastric intubation during gestational days 7-20. The pure control group received ad libitum laboratory chow and water with no other treatment. The hippocampi of fetal-ethanol and control pups were examined at the postnatal day (PD)1, PD10, PD30 and PD60. Moderate fetal-ethanol exposure and prenatal intubation stress caused a significant increase in molecular factors relating to inflammation (iNOS) and cell survival/apoptosis pathways (PTEN, GSK-3 and ERK) at birth, with a rapid compensation from these developmental deficits upon removal of alcohol at PD10. Indeed, an increase in ERK1/2 and JNK1/2 activation at PD30 was observed with ethanol consumption. It indicates that the recovery process in A and IC brains started soon after the birth upon the ethanol and stressor withdrawal and continued until the adulthood.

Thymoquinone activates MAPK pathway in hippocampus of streptozotocin-treated rat model.

Streptozotocin (STZ), a glucosamine-nitrosourea compound, produces deficiencies in learning, memory, and cognitive functions when it was administered intracerebroventricularly (i.c.v). In molecular level, increase in neuroinflammation and oxidative stress in brain, and decrease in the number of surviving neurons are the outcomes of STZ administration. Herein, we aimed to investigate the effect of thymoquinone (TQ), an anti-inflammatory, immunomodulatory and neuroprotective agent, on STZ-induced neurodegeneration in rats. For this purpose, bilateral i.c.v. injection of STZ (3 mg/kg) was given to adult female rats on days 1 and 3. TQ (20 mg/kg/day in cornoil) was administered intragastrically to rats for 15 days starting from the 15th day of STZ injection. The Morris water maze test and passive avoidance test were applied to measure the learning and memory performance of animals. Following the behavioral tests, all of the rats were sacrificed for evaluation of molecular alterations. Rats in the STZ-TQ group showed higher performance in passive avoidance test than rats in the STZ group whose memory performance declined compared to control group. The worse memory performance in STZ group was correlated with low number of surviving neurons and high number of degenerating neurons. In addition, an increase in APOE expression and a decrease in NGF expression were observed with STZ injection. Administration of TQ reversed these STZ-triggered cognitive and molecular alterations. In the present study, we observed the neuroregenerative effects of TQ by activation of JNK protein, upregulation of mir-124, and downregulation of ERK1/2 and NOS enzymes. The same ameliorative effect of TQ was also observed in the pTau protein expression. To sum up, we can say that the healing effect of TQ on STZ induced neurodegeneration opens a new door for the development of Alzheimer's disease treatment using natural products as an adjuvant when their action mechanism was explained in detail.

Thymoquinone Can Improve Neuronal Survival and Promote Neurogenesis in Rat Hippocampal Neurons.

SCOPE: Thymoquinone (TQ) has been used as a potential therapeutic for diseases such as cancer and diabetes. Herein, we aim to investigate the effect of TQ on behavioral and molecular parameters in healthy rat hippocampus. METHODS: TQ (20 mg kg-1  d-1 ) is administered intragastrically for 15 days to adult rats. After behavioral tests, the hippocampal tissues are investigated at the histological and molecular levels. RESULTS: In both dentate gyrus and cornu ammonis 1, TQ significantly increases the number of hippocampal neurons. This increase is supported by a significant increase in the doublecortin expression on both gene and protein levels. In addition, TQ significantly decreases the amount of Caspase-3 expression and the cleavage of poly ADP ribose polymerase, indicating a decrease in apoptosis. Further, ERK, GSK-3, JNK, CREB, and iNOS proteins are found to be positively regulated by TQ. However, the gene expression of synapsin, synaptophysin, NGF, AKT, Bax, NFkB, and p53 and the protein expression of BDNF and nNOS are not affected by TQ. CONCLUSION: These findings suggest that TQ has an enhancing effect on cell survival and neurogenesis in healthy hippocampus, rather inducing apoptosis in damaged neurons. This may proceed via ERK/JNK and CREB signaling pathways as a candidate acting mechanism for TQ.

Expression of cardiac inwardly rectifying potassium channels in pentylenetetrazole kindling model of epilepsy in rats.

Clinical and experimental studies show that epilepsy affects cardiac function; however, the underlying molecular mechanism has not been fully elucidated. Inwardly-rectifying potassium (Kir) channels transport K+ ions into excitable cells such as neurons and cardiomyocytes; they control the cell excitability by acting towards the repolarization phase of cardiac action potential. Kir channel expression has been previously shown to vary in epileptic brains, at the same time seizures are known to affect the autonomic nervous system. Kir channel expression in cardiac tissue is a possible mechanism for the explanation of cardiac pathology in epilepsy. We investigate the expression of Kir channels in epileptic cardiac tissue by using pentylenetetrazole (PTZ)-kindling model in rats. Our molecular analyses showed significant decrease in cardiac Kir channel mRNA and protein expression of PTZ-kindled rats. Interestingly, both Kir2.x, which directs IK1 flux in ventricular tissue and Kir3.x, which is responsible for IKACh in the atria, were observed to decrease significantly. Kir channel expression also differs between females and males. This is the first study to our knowledge in epileptic cardiac tissue showing the expression of Kir channels. Our results show that Kir channels may play a role in cardiac pathology associated with epilepsy.

Evidence that activation of P2X7R does not exacerbate neuronal death after optic nerve transection and focal cerebral ischemia in mice.

Conflicting data in the literature about the function of P2X7R in survival following ischemia necessitates the conductance of in-depth studies. To investigate the impacts of activation vs inhibition of the receptor on neuronal survival as well as the downstream signaling cascades, in addition to optic nerve transection (ONT), 30min and 90min of middle cerebral artery occlusion (MCAo) models were performed in mice. Intracellular calcium levels were assessed in primary cortical neuron cultures. Here, we show that P2X7R antagonist Brilliant Blue G (BBG) decreased DNA fragmentation, infarct volume, brain swelling, neurological deficit scores and activation of microglial cells after focal cerebral ischemia. BBG also significantly increased the number of surviving retinal ganglion cells (RGCs) after ONT and the number of surviving neurons following MCAo. Importantly, receptor agonist BzATP resulted in increased activation of microglial cells and induced phosphorylation of ERK, AKT and JNK. These results indicated that inhibition of P2X7R with BBG promoted neuronal survival, not through the activation of survival kinase pathways, but possibly by improved intracellular Ca2+ overload and decreased the levels of Caspase 1, IL-1ß and Bax proteins. On the other hand, BzATP-mediated increased number of activated microglia and increased survival kinase levels in addition to increased caspase-1 and IL-1ß levels indicate the complex nature of the P2X7 receptor-mediated signaling in neuronal injury.