1
|
Markus RP, Sousa KS, Ulrich H, Ferreira ZS. Partners in health and disease: pineal gland and purinergic signalling. Purinergic Signal 2024:10.1007/s11302-024-10037-8. [PMID: 39031242 DOI: 10.1007/s11302-024-10037-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2024] [Accepted: 07/02/2024] [Indexed: 07/22/2024] Open
Abstract
In mammal's pineal glands, ATP interacts with the high-affinity P2Y1 and the low-affinity P2X7 receptors. ATP released from sympathetic nerve terminals potentiates noradrenaline-induced serotonin N-acetyltransferase (Snat) transcription, N-acetylserotonin (NAS), and melatonin (MLT) synthesis. Circulating melatonin impairs the expression of adhesion molecules in endothelial cells, blocking the migration of leukocytes. Acute defence response induced by pathogen- and danger/damage-associated molecular patterns (PAMPs and DAMPs) triggers the NF-κB pathway in pinealocytes and blocks the transcription of Snat. Therefore, the darkness hormone is not released, and neutrophils and monocytes migrate to the lesion sites. ATP released in high amounts from apoptotic and death cells was considered a DAMP, and the blockage of P2X7 receptors was tested as a new class of drugs for treating brain damage. However, this is not a simple equation. High ATP injected in a lateral ventricle blocked MLT, but not NAS, synthesis as it impairs the transcription of acetyl serotonin N-methyltransferase. NAS is released in the plasma and the cerebral spinal fluid. NAS also blocks the rolling and adhesion of leukocytes to endothelial cells. Otherwise, it is metabolised specifically in each brain area to provide the requested concentration of MLT as a neuroprotector. As observed in physiological conditions, high extracellular ATP, different from the other DAMPs, reports the environmental light/dark cycle rhythm because NAS substitutes MLT as the nocturnal chemical indicator, the darkness hormone. Thus, blocking the P2X7R should not be considered a universal therapy for improving acute strokes, as MLT and ATP are partners in health and disease.
Collapse
Affiliation(s)
- Regina P Markus
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.
| | - Kassiano S Sousa
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil
| | - Henning Ulrich
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo, Brazil
| | - Zulma S Ferreira
- Laboratory of Chronopharmacology, Department of Physiology, Institute of Biosciences, University of São Paulo, São Paulo, Brazil.
| |
Collapse
|
2
|
Zeng T, Liu J, Zhang W, Yu Y, Ye X, Huang Q, Li P, Jiang Q. Update on the mechanism of microglia involvement in post-stroke cognitive impairment. Front Aging Neurosci 2024; 16:1366710. [PMID: 38887610 PMCID: PMC11181926 DOI: 10.3389/fnagi.2024.1366710] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Accepted: 05/21/2024] [Indexed: 06/20/2024] Open
Abstract
Post-stroke cognitive impairment (PSCI) is a clinical syndrome characterized by cognitive deficits that manifest following a stroke and persist for up to 6 months post-event. This condition is grave, severely compromising patient quality of life and longevity, while also imposing substantial economic burdens on societies worldwide. Despite significant advancements in identifying risk factors for PSCI, research into its underlying mechanisms and therapeutic interventions remains inadequate. Microglia, the brain's primary immune effector cells, are pivotal in maintaining, nurturing, defending, and repairing neuronal function, a process intrinsically linked to PSCI's progression. Thus, investigating microglial activation and mechanisms in PSCI is crucial. This paper aims to foster new preventive and therapeutic approaches for PSCI by elucidating the roles, mechanisms, and characteristics of microglia in the condition.
Collapse
Affiliation(s)
- Tianxiang Zeng
- Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| | - Jun Liu
- Department of Neurosurgery, The 2 Affiliated Hospital, Jiangxi Medical College, Nanchang University, Nanchang, Jiangxi, China
| | - Wenjun Zhang
- Department of Recovery Medicine, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| | - Yanyan Yu
- Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| | - Xinyun Ye
- Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| | - Qianliang Huang
- Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| | - Peng Li
- Department of Neurosurgery, Institute of Brain Diseases, Nanfang Hospital of Southern Medical University, Guangzhou, China
| | - Qiuhua Jiang
- Department of Neurosurgery, The Affiliated Ganzhou Hospital, Jiangxi Medical College, Nanchang University, Ganzhou, Jiangxi, China
| |
Collapse
|
3
|
Hirayama Y, Le HPN, Hashimoto H, Ishii I, Koizumi S, Anzai N. Preconditioning-Induced Facilitation of Lactate Release from Astrocytes Is Essential for Brain Ischemic Tolerance. eNeuro 2024; 11:ENEURO.0494-23.2024. [PMID: 38604775 PMCID: PMC11064122 DOI: 10.1523/eneuro.0494-23.2024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2023] [Revised: 03/27/2024] [Accepted: 04/05/2024] [Indexed: 04/13/2024] Open
Abstract
A sublethal ischemic episode [termed preconditioning (PC)] protects neurons in the brain against a subsequent severe ischemic injury. This phenomenon is known as brain ischemic tolerance and has received much attention from researchers because of its robust neuroprotective effects. We have previously reported that PC activates astrocytes and subsequently upregulates P2X7 receptors, thereby leading to ischemic tolerance. However, the downstream signals of P2X7 receptors that are responsible for PC-induced ischemic tolerance remain unknown. Here, we show that PC-induced P2X7 receptor-mediated lactate release from astrocytes has an indispensable role in this event. Using a transient focal cerebral ischemia model caused by middle cerebral artery occlusion, extracellular lactate levels during severe ischemia were significantly increased in mice who experienced PC; this increase was dependent on P2X7 receptors. In addition, the intracerebroventricular injection of lactate protected against cerebral ischemic injury. In in vitro experiments, although stimulation of astrocytes with the P2X7 receptor agonist BzATP had no effect on the protein levels of monocarboxylate transporter (MCT) 1 and MCT4 (which are responsible for lactate release from astrocytes), BzATP induced the plasma membrane translocation of these MCTs via their chaperone CD147. Importantly, CD147 was increased in activated astrocytes after PC, and CD147-blocking antibody abolished the PC-induced facilitation of astrocytic lactate release and ischemic tolerance. Taken together, our findings suggest that astrocytes induce ischemic tolerance via P2X7 receptor-mediated lactate release.
Collapse
Affiliation(s)
- Yuri Hirayama
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Ha Pham Ngoc Le
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Hirofumi Hashimoto
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| | - Itsuko Ishii
- Division of Pharmacy, Chiba University Hospital, Chiba 260-8677, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Yamanashi 409-3898, Japan
- GLIA Center, University of Yamanashi, Yamanashi 409-3898, Japan
| | - Naohiko Anzai
- Department of Pharmacology, Chiba University Graduate School of Medicine, Chiba 260-8670, Japan
| |
Collapse
|
4
|
Ohara H, Takeuchi F, Kato N, Nabika T. Genotypes of Stim1 and the proximal region on chromosome 1 exert opposite effects on stroke susceptibility in stroke-prone spontaneously hypertensive rat. J Hypertens 2024; 42:118-128. [PMID: 37711097 DOI: 10.1097/hjh.0000000000003566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/16/2023]
Abstract
BACKGROUND The stroke-prone spontaneously hypertensive rat (SHRSP) is a genetic model for cerebral stroke. Although a recent study on a congenic SHRSP suggested that a nonsense mutation in stromal interaction molecule 1 ( Stim1 ) encoding a major component of store-operated Ca 2+ entry was a causal variant for stroke in SHRSP, this was not conclusive because the congenic region including Stim1 in that rat was too wide. On the other hand, we demonstrated that the Wistar-Kyoto (WKY)-derived congenic fragment adjacent to Stim1 exacerbated stroke susceptibility in a congenic SHRSP called SPwch1.71. In the present study, we directly examined the effects of the Stim1 genotype on stroke susceptibility using SHRSP in which wild-type Stim1 was knocked in (called Stim1 -KI SHRSP). The combined effects of Stim1 and the congenic fragment of SPwch1.71 were also investigated. METHODS Stroke susceptibility was assessed by the stroke symptom-free and survival periods based on observations of behavioral symptoms and reductions in body weight. RESULTS Stim1 -KI SHRSP was more resistant to, while SPwch1.71 was more susceptible to stroke than the original SHRSP. Introgression of the wild-type Stim1 of Stim1 -KI SHRSP into SPwch1.71 by the generation of F1 rats ameliorated stroke susceptibility in SPwch1.71. Gene expression, whole-genome sequencing, and biochemical analyses identified Art2b , Folr1 , and Pde2a as possible candidate genes accelerating stroke in SPwch1.71. CONCLUSION The substitution of SHRSP-type Stim1 to wild-type Stim1 ameliorated stroke susceptibility in both SHRSP and SPwch1.71, indicating that the nonsense mutation in Stim1 is causally related to stroke susceptibility in SHRSP.
Collapse
Affiliation(s)
- Hiroki Ohara
- Department of Functional Pathology, Faculty of Medicine, Shimane University, Izumo
| | - Fumihiko Takeuchi
- Department of Gene Diagnostics and Therapeutics
- Medical Genomics Center, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Norihiro Kato
- Department of Gene Diagnostics and Therapeutics
- Medical Genomics Center, Research Institute, National Center for Global Health and Medicine, Tokyo, Japan
| | - Toru Nabika
- Department of Functional Pathology, Faculty of Medicine, Shimane University, Izumo
| |
Collapse
|
5
|
Le YP, Saito K, Parajuli B, Sakai K, Kubota Y, Miyakawa M, Shinozaki Y, Shigetomi E, Koizumi S. Severity of Peripheral Infection Differentially Affects Brain Functions in Mice via Microglia-Dependent and -Independent Mechanisms. Int J Mol Sci 2023; 24:17597. [PMID: 38139424 PMCID: PMC10743593 DOI: 10.3390/ijms242417597] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2023] [Revised: 12/14/2023] [Accepted: 12/14/2023] [Indexed: 12/24/2023] Open
Abstract
Peripheral infection induces inflammation in peripheral tissues and the brain, impacting brain function. Glial cells are key players in this process. However, the effects of peripheral infection on glial activation and brain function remain unknown. Here, we showed that varying degrees of peripheral infection had different effects on the regulation of brain functions by microglia-dependent and -independent mechanisms. Acute mild infection (one-day LPS challenge: 1LPS) exacerbated middle cerebral artery occlusion (MCAO) injury, and severe infection (four-day LPS challenge: 4LPS) for one week suppressed it. MCAO injury was assessed by triphenyltetrazolium chloride staining. We observed early activation of microglia in the 1LPS and 4LPS groups. Depleting microglia with a colony-stimulating factor-1 receptor (CSF1R) antagonist had no effect on 1LPS-induced brain injury exacerbation but abolished 4LPS-induced protection, indicating microglial independence and dependence, respectively. Microglia-independent exacerbation caused by 1LPS involved peripheral immune cells including macrophages. RNA sequencing analysis of 4LPS-treated microglia revealed increased factors related to anti-inflammatory and neuronal tissue repair, suggesting their association with the protective effect. In conclusion, varying degrees of peripheral inflammation had contradictory effects (exacerbation vs. protection) on MCAO, which may be attributed to microglial dependence. Our findings highlight the significant impact of peripheral infection on brain function, particularly in relation to glial cells.
Collapse
Affiliation(s)
- Yen-Phung Le
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Kozo Saito
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Bijay Parajuli
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Kent Sakai
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Yuto Kubota
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Miho Miyakawa
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Youichi Shinozaki
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Eiji Shigetomi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| | - Schuichi Koizumi
- Department of Neuropharmacology, Interdisciplinary Graduate School of Medicine, University of Yamanashi, Chuo 409-3898, Japan; (Y.-P.L.); (K.S.); (B.P.); (K.S.); (Y.K.); (M.M.); (Y.S.); (E.S.)
- GLIA Center, University of Yamanashi, Chuo 409-3898, Japan
| |
Collapse
|
6
|
Xie X, Liu J. New role of astrocytes in neuroprotective mechanisms after ischemic stroke. ARQUIVOS DE NEURO-PSIQUIATRIA 2023; 81:748-755. [PMID: 37647906 PMCID: PMC10468254 DOI: 10.1055/s-0043-1770352] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Accepted: 01/15/2023] [Indexed: 09/01/2023]
Abstract
Astrocytes are the most abundant cell subtypes in the central nervous system. Previous studies believed that astrocytes are supporting cells in the brain, which only provide nutrients for neurons. However, recent studies have found that astrocytes have more crucial and complex functions in the brain, such as neurogenesis, phagocytosis, and ischemic tolerance. After an ischemic stroke, the activated astrocytes can exert neuroprotective or neurotoxic effects through a variety of pathways. In this review, we will discuss the neuroprotective mechanisms of astrocytes in cerebral ischemia, and mainly focus on reactive astrocytosis or glial scar, neurogenesis, phagocytosis, and cerebral ischemic tolerance, for providing new strategies for the clinical treatment of stroke.
Collapse
Affiliation(s)
- Xiaoyun Xie
- Guangxi Medical University, The First Affiliated Hospital, Department of Neurology, Nanning, Guangxi, China.
| | - Jingli Liu
- Guangxi Medical University, The First Affiliated Hospital, Department of Neurology, Nanning, Guangxi, China.
| |
Collapse
|
7
|
Ahn YH, Tang Y, Illes P. The neuroinflammatory astrocytic P2X7 receptor: Alzheimer's disease, ischemic brain injury, and epileptic state. Expert Opin Ther Targets 2023; 27:763-778. [PMID: 37712394 DOI: 10.1080/14728222.2023.2258281] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Revised: 08/04/2023] [Accepted: 09/08/2023] [Indexed: 09/16/2023]
Abstract
INTRODUCTION Astrocytes have previously been considered as cells supporting neuronal functions, but they are now recognized as active players in maintaining central nervous system (CNS) homeostasis. Astrocytes can communicate with other CNS cells, i.e. through the gliotransmitter ATP and P2X7 receptors (Rs). AREAS COVERED In this review, we will discuss how the P2X7R initiates the release of gliotransmitters and proinflammatory cytokines/chemokines, thereby establishing a dialog between astrocytes and neurons and, in addition, causing neuroinflammation. In astrocytes, dysregulation of P2X7Rs has been associated with neurodegenerative illnesses such as Alzheimer's disease (AD), as well as the consequences of cerebral ischemic injury and status epilepticus (SE). EXPERT OPINION Although all CNS cells are possible sources of ATP release, the targets of this ATP are primarily at microglial cells. However, astrocytes also contain ATP-sensitive P2X7Rs and have in addition the peculiar property over microglia to continuously interact with neurons via not only inflammatory mediators but also gliotransmitters, such as adenosine 5'-triphosphate (ATP), glutamate, γ-amino butyric acid (GABA), and D-serine. Cellular damage arising during AD, cerebral ischemia, and SE via P2X7R activation is superimposed upon the original disease, and their prevention by blood-brain barrier permeable pharmacological antagonists is a valid therapeutic option.
Collapse
Affiliation(s)
- Young Ha Ahn
- International Joint Research Center on Purinergic Signaling of Sichuan Province, Chengdu University of TCM, Chengdu, China
| | - Yong Tang
- International Joint Research Center on Purinergic Signaling of Sichuan Province, Chengdu University of TCM, Chengdu, China
- School of Acupuncture and Tuina, Chengdu University of TCM, Chengdu, China
| | - Peter Illes
- International Joint Research Center on Purinergic Signaling of Sichuan Province, Chengdu University of TCM, Chengdu, China
- Rudolf Boehm Institute of Pharmacology and Toxicology, University of Leipzig, Leipzig, Germany
| |
Collapse
|
8
|
Blocking P2RX7 Attenuates Ferroptosis in Endothelium and Reduces HG-induced Hemorrhagic Transformation After MCAO by Inhibiting ERK1/2 and P53 Signaling Pathways. Mol Neurobiol 2023; 60:460-479. [PMID: 36282438 DOI: 10.1007/s12035-022-03092-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Accepted: 10/14/2022] [Indexed: 02/08/2023]
Abstract
Hyperglycemia is a risk factor for poor prognosis after acute ischemic stroke and promote the occurrence of hemorrhagic transformation (HT). The activation of P2RX7 play an important role in endotheliocyte damage and BBB disruption. Ferroptosis is a novel pattern of programmed cell death caused by the accumulation of intracellular iron and lipid peroxidation, resulting in ROS production and cell death. This study is to explore the mechanism of P2RX7 in reducing HT pathogenesis after acute ischemic stroke through regulating endotheliocyte ferroptosis. Male SD rats were performed to establish middle cerebral artery occlusion (MCAO) model injected with 50% high glucose (HG) and HUVECs were subjected to OGD/R treated with high glucose (30 mM) for establishing HT model in vivo and in vitro. P2RX7 inhibitor (BBG), and P2RX7 small interfering RNAs (siRNA) were used to investigate the role of P2RX7 in BBB after MCAO in vivo and OGD/R in vitro, respectively. The neurological deficits, infarct volume, degree of intracranial hemorrhage, integrity of the BBB, immunoblotting, and immunofluorescence were evaluated at 24 h after MCAO. Our study found that the level of P2RX7 was gradually increased after MCAO and/or treated with HG. Our results showed that treatment with HG after MCAO can aggravate neurological deficits, infarct volume, oxidative stress, iron accumulation, and BBB injury in HT model, and HG-induced HUVECs damage. The inhibition of P2RX7 reversed the damage effect of HG, significantly downregulated the expression level of P53, HO-1, and p-ERK1/2 and upregulated the level of SLC7A11 and GPX4, which implicated that P2RX7 inhibition could attenuate oxidative stress and ferroptosis of endothelium in vivo and in vitro. Our data provided evidence that the P2RX7 play an important role in HG-associated oxidative stress, endothelial damage, and BBB disruption, which regulates HG-induced HT by ERK1/2 and P53 signaling pathways after MCAO.
Collapse
|
9
|
Takahashi H, Yamamoto T, Tsuboi A. Molecular mechanisms underlying activity-dependent ischemic tolerance in the brain. Neurosci Res 2023; 186:3-9. [PMID: 36244569 DOI: 10.1016/j.neures.2022.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 10/05/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022]
Abstract
Ischemic stroke is one of the leading causes of death and disability worldwide. The inhibition of cerebral blood flow triggers intertwined pathological events, resulting in cell death and loss of brain function. Interestingly, animals pre-exposed to short-term ischemia can tolerate subsequent severe ischemia. This phenomenon is called ischemic tolerance and is also triggered by other noxious stimuli. However, whether short-term exposure to non-noxious stimuli can induce ischemic tolerance remains unknown. Recently, we found that pre-exposing mice to an enriched environment for 40 min is sufficient to facilitate cell survival after a subsequent stroke. The neuroprotective process depends on the neuronal activity soon before stroke, of which the activity-dependent transcription factor Npas4 is essential. Excessive Ca2+ influx triggers Npas4 expression in ischemic neurons, leading to the activation of neuroprotective programs. Pre-induction of Npas4 in the normal brain effectively supports cell survival after stroke. Furthermore, our study revealed that Npas4 regulates L-type voltage-gated Ca2+ channels through expression of the small Ras-like GTPase Gem in ischemic neurons. Ischemic tolerance is a good model for understanding how to promote neuroprotective mechanisms in the normal and injured brain. Here, we highlight activity-dependent ischemic tolerance and discuss its role in promoting neuroprotection against stroke.
Collapse
Affiliation(s)
- Hiroo Takahashi
- Department of Molecular Neurobiology, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan.
| | - Tohru Yamamoto
- Department of Molecular Neurobiology, Faculty of Medicine, Kagawa University, Kagawa 761-0793, Japan
| | - Akio Tsuboi
- Dynamic Brain Network Laboratory, Graduate School of Frontier Biosciences, Osaka University, Suita 565-0871, Japan
| |
Collapse
|
10
|
Blocking P2X7 by intracerebroventricular injection of P2X7-specific nanobodies reduces stroke lesions. J Neuroinflammation 2022; 19:256. [PMID: 36224611 PMCID: PMC9559872 DOI: 10.1186/s12974-022-02601-z] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 09/25/2022] [Indexed: 01/15/2023] Open
Abstract
BACKGROUND Previous studies have demonstrated that purinergic receptors could be therapeutic targets to modulate the inflammatory response in multiple models of brain diseases. However, tools for the selective and efficient targeting of these receptors are lacking. The development of new P2X7-specific nanobodies (nbs) has enabled us to effectively block the P2X7 channel. METHODS Temporary middle cerebral artery occlusion (tMCAO) in wild-type (wt) and P2X7 transgenic (tg) mice was used to model ischemic stroke. Adenosine triphosphate (ATP) release was assessed in transgenic ATP sensor mice. Stroke size was measured after P2X7-specific nbs were injected intravenously (iv) and intracerebroventricularly (icv) directly before tMCAO surgery. In vitro cultured microglia were used to investigate calcium influx, pore formation via 4,6-diamidino-2-phenylindole (DAPI) uptake, caspase 1 activation and interleukin (IL)-1β release after incubation with the P2X7-specific nbs. RESULTS Transgenic ATP sensor mice showed an increase in ATP release in the ischemic hemisphere compared to the contralateral hemisphere or the sham-treated mice up to 24 h after stroke. P2X7-overexpressing mice had a significantly greater stroke size 24 h after tMCAO surgery. In vitro experiments with primary microglial cells demonstrated that P2X7-specific nbs could inhibit ATP-triggered calcium influx and the formation of membrane pores, as measured by Fluo4 fluorescence or DAPI uptake. In microglia, we found lower caspase 1 activity and subsequently lower IL-1β release after P2X7-specific nb treatment. The intravenous injection of P2X7-specific nbs compared to isotype controls before tMCAO surgery did not result in a smaller stroke size. As demonstrated by fluorescence-activated cell sorting (FACS), after stroke, iv injected nbs bound to brain-infiltrated macrophages but not to brain resident microglia, indicating insufficient crossing of the blood-brain barrier of the nbs. Therefore, we directly icv injected the P2X7-specific nbs or the isotype nbs. After icv injection of 30 µg of P2X7 specific nbs, P2X7 specific nbs bound sufficiently to microglia and reduced stroke size. CONCLUSION Mechanistically, we can show that there is a substantial increase of ATP locally after stroke and that blockage of the ATP receptor P2X7 by icv injected P2X7-specific nbs can reduce ischemic tissue damage.
Collapse
|
11
|
Koizumi S, Hirayama Y. Ischemic Tolerance Induced by Glial Cells. Neurochem Res 2022; 47:2522-2528. [PMID: 35920970 PMCID: PMC9463280 DOI: 10.1007/s11064-022-03704-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/09/2022] [Accepted: 07/16/2022] [Indexed: 11/05/2022]
Abstract
Ischemic tolerance is a phenomenon in which resistance to subsequent invasive ischemia is acquired by a preceding noninvasive ischemic application, and is observed in many organs, including the brain, the organ most vulnerable to ischemic insult. To date, much research has been conducted on cerebral ischemic tolerance as a cell-autonomous action of neurons. In this article, we review the essential roles of microglia and astrocytes in the acquisition of ischemic tolerance through neuron-non-autonomous mechanisms, where the two types of glial cells function in a concerted manner to induce ischemic tolerance.
Collapse
Affiliation(s)
- Schuichi Koizumi
- Department of Neuropharmacology, Yamanashi, Japan. .,Yamanashi GLIA Center, Interdisciplinary Graduate School of Medicine, University of Yamanashi, 409-3898, Yamanashi, Japan.
| | - Yuri Hirayama
- Department of Neuropharmacology, Yamanashi, Japan.,Department of Pharmacology, Graduate School of Medicine, Chiba University, 260-8670, Chiba, Japan
| |
Collapse
|
12
|
P2X7 Receptors in Astrocytes: A Switch for Ischemic Tolerance. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27123655. [PMID: 35744780 PMCID: PMC9228417 DOI: 10.3390/molecules27123655] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2022] [Revised: 06/02/2022] [Accepted: 06/03/2022] [Indexed: 11/17/2022]
Abstract
A sub-lethal ischemic episode (preconditioning [PC]) protects neurons against a subsequent lethal ischemic injury. This phenomenon is known as ischemic tolerance. PC itself does not cause brain damage, but affects glial responses, especially astrocytes, and transforms them into an ischemia-resistant phenotype. P2X7 receptors (P2X7Rs) in astrocytes play essential roles in PC. Although P2X7Rs trigger inflammatory and toxic responses, PC-induced P2X7Rs in astrocytes function as a switch to protect the brain against ischemia. In this review, we focus on P2X7Rs and summarize recent developments on how astrocytes control P2X7Rs and what molecular mechanisms they use to induce ischemic tolerance.
Collapse
|
13
|
Heras-Romero Y, Morales-Guadarrama A, Santana-Martínez R, Ponce I, Rincón-Heredia R, Poot-Hernández AC, Martínez-Moreno A, Urrieta E, Bernal-Vicente BN, Campero-Romero AN, Moreno-Castilla P, Greig NH, Escobar ML, Concha L, Tovar-Y-Romo LB. Improved post-stroke spontaneous recovery by astrocytic extracellular vesicles. Mol Ther 2022; 30:798-815. [PMID: 34563674 PMCID: PMC8821969 DOI: 10.1016/j.ymthe.2021.09.023] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 09/08/2021] [Accepted: 09/20/2021] [Indexed: 02/04/2023] Open
Abstract
Spontaneous recovery after a stroke accounts for a significant part of the neurological recovery in patients. However limited, the spontaneous recovery is mechanistically driven by axonal restorative processes for which several molecular cues have been previously described. We report the acceleration of spontaneous recovery in a preclinical model of ischemia/reperfusion in rats via a single intracerebroventricular administration of extracellular vesicles released from primary cortical astrocytes. We used magnetic resonance imaging and confocal and multiphoton microscopy to correlate the structural remodeling of the corpus callosum and striatocortical circuits with neurological performance during 21 days. We also evaluated the functionality of the corpus callosum by repetitive recordings of compound action potentials to show that the recovery facilitated by astrocytic extracellular vesicles was both anatomical and functional. Our data provide compelling evidence that astrocytes can hasten the basal recovery that naturally occurs post-stroke through the release of cellular mediators contained in extracellular vesicles.
Collapse
Affiliation(s)
- Yessica Heras-Romero
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Axayacatl Morales-Guadarrama
- Departmento de Ingeniería Eléctrica, Universidad Autónoma Metropolitana Iztapalapa, Mexico City, Mexico; National Center for Medical Imaging and Instrumentation Research, Mexico City, Mexico
| | - Ricardo Santana-Martínez
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Isaac Ponce
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Ruth Rincón-Heredia
- Microscopy Core Unit, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Augusto César Poot-Hernández
- Bioinformatics Core Unit, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Araceli Martínez-Moreno
- Divisíon de Investigación y Estudios de Posgrado, Facultad de Psicología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Esteban Urrieta
- Divisíon de Investigación y Estudios de Posgrado, Facultad de Psicología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Berenice N Bernal-Vicente
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Aura N Campero-Romero
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Perla Moreno-Castilla
- Laboratory of Neurocognitive Aging, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Nigel H Greig
- Drug Design & Development Section, National Institute on Aging, National Institutes of Health, Baltimore, MD, USA
| | - Martha L Escobar
- Divisíon de Investigación y Estudios de Posgrado, Facultad de Psicología, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Luis Concha
- Department of Behavioral and Cognitive Neurobiology, Instituto de Neurobiología, Universidad Nacional Autónoma de México, Juriquilla, Querétaro, Mexico
| | - Luis B Tovar-Y-Romo
- Department of Molecular Neuropathology, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico.
| |
Collapse
|