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Martínez-Torres AM, Morán J. Aquaporin 4 and the endocannabinoid system: a potential therapeutic target in brain injury. Exp Brain Res 2024:10.1007/s00221-024-06896-7. [PMID: 39043897 DOI: 10.1007/s00221-024-06896-7] [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: 02/20/2024] [Accepted: 07/14/2024] [Indexed: 07/25/2024]
Abstract
Brain edema is a critical complication arising from stroke and traumatic brain injury (TBI) with an important impact on patient recovery and can lead to long-term consequences. Therapeutic options to reduce edema progression are limited with variable patient outcomes. Aquaporin 4 (AQP4) is a water channel that allows bidirectional water diffusion across the astrocyte membrane and participates in the distinct phases of cerebral edema. The absence or inhibition of this channel has been demonstrated to ameliorate edema and brain damage. The endocannabinoid system (ECS) is a neuromodulator system with a wide expression in the brain and its activation has shown neuroprotective properties in diverse models of neuronal damage. This review describes and discusses the major features of ECS and AQP4 and their role during brain damage, observing that ECS stimulation reduces edema and injury size in diverse models of brain damage, however, the relationship between AQP4 expression and dynamics and ECS activation remains unclear. The research on these topics holds promising therapeutic implications for the treatment of brain edema following stroke and TBI.
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Affiliation(s)
- Ari Misael Martínez-Torres
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Apartado Postal 70-253, 04510, Ciudad de Mexico, México
| | - Julio Morán
- División de Neurociencias, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Coyoacán, Apartado Postal 70-253, 04510, Ciudad de Mexico, México.
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2
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Rostami F, Jaafari Suha A, Janahmadi M, Hosseinmardi N. Aquaporin-4 inhibition attenuates Pentylenetetrazole-induced behavioral seizures and cognitive impairments in kindled rats. Physiol Behav 2024; 278:114521. [PMID: 38492911 DOI: 10.1016/j.physbeh.2024.114521] [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: 10/10/2023] [Revised: 03/08/2024] [Accepted: 03/13/2024] [Indexed: 03/18/2024]
Abstract
Epilepsy is a neurological condition distinguished by recurrent and unexpected seizures. Astrocytic channels and transporters are essential for maintaining normal neuronal functionality. The astrocytic water channel, aquaporin-4 (AQP4), which plays a pivotal role in regulating water homeostasis, is a potential target for epileptogenesis. In present study, we examined the effect of different doses (10, 50, 100 μM and 5 mM) of AQP4 inhibitor, 2-nicotinamide-1, 3, 4-thiadiazole (TGN-020), during kindling acquisition, on seizure parameters and seizure-induced cognitive impairments. Animals were kindled by injection of pentylenetetrazole (PTZ: 37.5 mg/kg, i.p.). TGN-020 was administered into the right lateral cerebral ventricle 30 min before PTZ every alternate day. Seizure parameters were assessed 20 min after PTZ administration. One day following the last PTZ injection, memory performance was investigated using spontaneous alternation in Y-maze and novel object recognition (NOR) tests. The inhibition of AQP4 during the kindling process significantly decreased the maximal seizure stage and seizure duration (two-way ANOVA, P = 0.0001) and increased the latency of seizure onset and the number of PTZ injections required to induce different seizure stages (one-way ANOVA, P = 0.0001). Compared to kindled rats, the results of the NOR tests showed that AQP4 inhibition during PTZ-kindling prevented recognition memory impairment. Based on these results, AQP4 could be involved in seizure development and seizure-induced cognitive impairment. More investigation is required to fully understand the complex interactions between seizure activity, water homeostasis, and cognitive dysfunction, which may help identify potential therapeutic targets for these conditions.
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Affiliation(s)
- Fatemeh Rostami
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology research center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Ali Jaafari Suha
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology research center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahyar Janahmadi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology research center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Narges Hosseinmardi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran; Neurophysiology research center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Rivas-Alonso V, Cáceres J, Ramírez-Benítez E, Solís-Vivanco R. Cognitive impairment and its association with clinical variables in Mexican persons with neuromyelitis optica spectrum disorder. Mult Scler Relat Disord 2024; 86:105612. [PMID: 38614055 DOI: 10.1016/j.msard.2024.105612] [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: 08/28/2023] [Revised: 01/19/2024] [Accepted: 04/07/2024] [Indexed: 04/15/2024]
Abstract
INTRODUCTION Cognitive impairment has a substantial impact on the daily function of people living with demyelinating diseases. However, the study of cognitive failures and their association with clinical variables in people suffering from neuromyelitis optica spectrum disorder (NMOSD) has been scarce, especially in the latin american (Mexican) population at early and middle stages of the disease. METHOD We applied the Rao's Brief Repeatable Battery of Neuropsychological tests and obtained data of lesion burden through magnetic resonance imaging (MRI), expression of AQPQ4-IgG antibodies, and degree of disability in 30 patients with NMOSD and 30 healthy participants as a control group. RESULTS About half of the NMOSD patients (47%) showed some degree of cognitive impairment, especially in the executive domain compared to the control group. Executive function scores were positively associated with the degree of physical disability. We found no associations between cognitive dysfunction and disease duration, AQPQ4-IgG antibodies, lesion burden, nor depression. CONCLUSIONS Executive functioning impairment is present in NMOSD and may predict the degree of functional disability in patients. Cognitive failures were not associated with immunological or radiological data, which emphasizes the relevance of applying systematic neuropsychological assessments in this clinical population.
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Affiliation(s)
- Verónica Rivas-Alonso
- Multiple Sclerosis and Demyelinating Disorders Clinic, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez (INNNMVS), Mexico
| | - Jairo Cáceres
- Multiple Sclerosis and Demyelinating Disorders Clinic, Instituto Nacional de Neurología y Neurocirugía Manuel Velasco Suárez (INNNMVS), Mexico
| | - Edwin Ramírez-Benítez
- Laboratory of Cognitive and Clinical Neurophysiology, INNNMVS, Insurgentes Sur 3877, Col. La Fama, Tlalpan. C.P. 14600. Mexico City, Mexico; Faculty of Psychology, Universidad Nacional Autónoma de México, Mexico
| | - Rodolfo Solís-Vivanco
- Laboratory of Cognitive and Clinical Neurophysiology, INNNMVS, Insurgentes Sur 3877, Col. La Fama, Tlalpan. C.P. 14600. Mexico City, Mexico; Faculty of Psychology, Universidad Nacional Autónoma de México, Mexico.
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Chen A, Hua J, Yuan J, Feng Y, Chen F, Zhou Y, Han T, Jiang W, Chen H. Ginkgolide B promotes spontaneous recovery and enhances endogenous netrin-1 after neonatal hypoxic-ischemic brain damage. Int J Dev Neurosci 2023; 83:740-752. [PMID: 37771243 DOI: 10.1002/jdn.10301] [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: 06/27/2023] [Revised: 08/16/2023] [Accepted: 08/24/2023] [Indexed: 09/30/2023] Open
Abstract
OBJECTIVES Perinatal hypoxic-ischemic encephalopathy (HIE) is a condition that can lead to long-term cognitive, motor, and behavioral impairments in newborns. Although brain hypothermia therapy is currently the standard treatment for HIE, it does not provide complete neuroprotection. As a result, there is a need to explore additional therapies to enhance treatment outcomes. This study aims to investigate the potential role of Ginkgolide B (GB) in promoting neuroplasticity and facilitating spontaneous recovery after HIE. METHODS In this study, we employed a neonatal rat model of HIE to investigate the effects of GB on spontaneous recovery. GB treatment was initiated 24 h after hypoxia and administered continuously for a duration of 14 days. We evaluated several outcome measures after the treatment period, including spontaneous behavioral recovery and brain repair. Additionally, we quantified the levels of netrin-1 in both plasma and the peri-ischemic zone after the occurrence of HIE. RESULTS We found that GB treatment significantly facilitated spontaneous behavioral recovery in the HIE pups. Furthermore, cognitive function was restored, and brain tissue repair had a noticeable acceleration. We observed increased cell proliferation in the subventricular, stratum, and subgranular zones. Of particular interest, we observed elevated levels of netrin-1 in both plasma and the ischemic penumbra following GB treatment. CONCLUSION Our findings suggest that GB promotes neuroplasticity and enhances spontaneous recovery in newborns affected by HIE. The observed upregulation of netrin-1 may be crucial in mediating these effects. These results highlight the promising potential of GB as a post-HIE therapy, particularly in enhancing spontaneous recovery and improving long-term outcomes.
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Affiliation(s)
- Aiming Chen
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Jun Hua
- Department of Neurology & Psychology, Shenzhen Traditional Chinese Medicine Hospital, Fourth Clinical Medical College of Guangzhou University of Chinese Medicine, Shenzhen, China
| | - Jun Yuan
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Yajuan Feng
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Fengzhan Chen
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Yongqin Zhou
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Ting Han
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Weiwei Jiang
- Department of Pediatrics, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
| | - Huiping Chen
- Department of Vasculocardiology, The Affiliated Taizhou Second People's Hospital of Yangzhou University, Taizhou, China
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Cha H, Choi JH, Jeon H, Kim JH, Kim M, Kim SJ, Park W, Lim JS, Lee E, Ahn JS, Kim JH, Hong SH, Park JE, Jung JH, Yoo HJ, Lee S. Aquaporin-4 Deficiency is Associated with Cognitive Impairment and Alterations in astrocyte-neuron Lactate Shuttle. Mol Neurobiol 2023; 60:6212-6226. [PMID: 37436602 DOI: 10.1007/s12035-023-03475-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 07/02/2023] [Indexed: 07/13/2023]
Abstract
Cognitive impairment refers to notable declines in cognitive abilities including memory, language, and emotional stability leading to the inability to accomplish essential activities of daily living. Astrocytes play an important role in cognitive function, and homeostasis of the astrocyte-neuron lactate shuttle (ANLS) system is essential for maintaining cognitive functions. Aquaporin-4 (AQP-4) is a water channel expressed in astrocytes and has been shown to be associated with various brain disorders, but the direct relationship between learning, memory, and AQP-4 is unclear. We examined the relationship between AQP-4 and cognitive functions related to learning and memory. Mice with genetic deletion of AQP-4 showed significant behavioral and emotional changes including hyperactivity and instability, and impaired cognitive functions such as spatial learning and memory retention. 18 F-FDG PET imaging showed significant metabolic changes in the brains of AQP-4 knockout mice such as reductions in glucose absorption. Such metabolic changes in the brain seemed to be the direct results of changes in the expression of metabolite transporters, as the mRNA levels of multiple glucose and lactate transporters in astrocytes and neurons were significantly decreased in the cortex and hippocampus of AQP-4 knockout mice. Indeed, AQP-4 knockout mice showed significantly higher accumulation of both glucose and lactate in their brains compared with wild-type mice. Our results show that the deficiency of AQP-4 can cause problems in the metabolic function of astrocytes and lead to cognitive impairment, and that the deficiency of AQP4 in astrocyte endfeet can cause abnormalities in the ANLS system.
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Affiliation(s)
- Hyeuk Cha
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- Department of Medical Science, Asan Medical Center, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jun Ho Choi
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Hanwool Jeon
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jae Hyun Kim
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Moinay Kim
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
| | - Su Jung Kim
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Wonhyoung Park
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Joon Seo Lim
- Clinical Research Center, Asan Medical Center, Asan Institute for Life Sciences, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Eunyeup Lee
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- Department of Medical Science, Asan Medical Center, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jae Sung Ahn
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jeong Hoon Kim
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Seok Ho Hong
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea
- University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Ji Eun Park
- University of Ulsan College of Medicine, Seoul, Republic of Korea
- Department of Neuroradiology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
| | - Jin Hwa Jung
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Hyun Ju Yoo
- University of Ulsan College of Medicine, Seoul, Republic of Korea
- Convergence Medicine Research Center, Asan Institute for Life Sciences, Asan Medical Center, Seoul, Republic of Korea
| | - Seungjoo Lee
- Department of Neurological Surgery, Asan Medical Center, University of Ulsan College of Medicine, 88, Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea.
- Department of Medical Science, Asan Medical Center, Asan Medical Institute of Convergence Science and Technology, University of Ulsan College of Medicine, Seoul, Republic of Korea.
- University of Ulsan College of Medicine, Seoul, Republic of Korea.
- Bio-Medical Institute of Technology, University of Ulsan College of Medicine, Seoul, Republic of Korea.
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Jazaeri SZ, Taghizadeh G, Babaei JF, Goudarzi S, Saadatmand P, Joghataei MT, Khanahmadi Z. Aquaporin 4 beyond a water channel; participation in motor, sensory, cognitive and psychological performances, a comprehensive review. Physiol Behav 2023; 271:114353. [PMID: 37714320 DOI: 10.1016/j.physbeh.2023.114353] [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: 06/05/2023] [Revised: 08/15/2023] [Accepted: 09/13/2023] [Indexed: 09/17/2023]
Abstract
Aquaporin 4 (AQP4) is a protein highly expressed in the central nervous system (CNS) and peripheral nervous system (PNS) as well as various other organs, whose different sites of action indicate its importance in various functions. AQP4 has a variety of essential roles beyond water homeostasis. In this article, we have for the first time summarized different roles of AQP4 in motor and sensory functions, besides cognitive and psychological performances, and most importantly, possible physiological mechanisms by which AQP4 can exert its effects. Furthermore, we demonstrated that AQP4 participates in pathology of different neurological disorders, various effects depending on the disease type. Since neurological diseases involve a spectrum of dysfunctions and due to the difficulty of obtaining a treatment that can simultaneously affect these deficits, it is therefore suggested that future studies consider the role of this protein in different functional impairments related to neurological disorders simultaneously or separately by targeting AQP4 expression and/or polarity modulation.
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Affiliation(s)
- Seyede Zohreh Jazaeri
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran
| | - Ghorban Taghizadeh
- Department of Occupational Therapy, School of Rehabilitation Sciences, Iran University of Medical Sciences, Tehran, Iran.
| | - Javad Fahanik Babaei
- Electrophysiology Research Center, Tehran University of Medical Sciences, Tehran, Iran
| | - Sepideh Goudarzi
- Experimental Medicine Research Center, Tehran University of medical Sciences, Tehran, Iran
| | - Pegah Saadatmand
- Department of Medical Physics, School of Medicine, Iran University of Medical Sciences, Tehran, Iran
| | - Mohammad Taghi Joghataei
- Department of Neuroscience, Faculty of Advanced Technologies in Medicine, Iran University of Medical Sciences, Tehran, Iran; Division of Neuroscience, Cellular and Molecular Research Center, Iran University of Medical Sciences, Tehran, Iran; Department of Anatomy, School of Medicine, Iran University of Medical Sciences, Tehran, Iran; Department of Innovation in Medical Education, Faculty of Medicine, Ottawa University, Ottawa, Canada.
| | - Zohreh Khanahmadi
- Department of Occupational Therapy, School of Rehabilitation Services, Isfahan University of Medical Sciences, Isfahan, Iran
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Davoudi S, Rahdar M, Hosseinmardi N, Behzadi G, Janahmadi M. Chronic inhibition of astrocytic aquaporin-4 induces autistic-like behavior in control rat offspring similar to maternal exposure to valproic acid. Physiol Behav 2023:114286. [PMID: 37402416 DOI: 10.1016/j.physbeh.2023.114286] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Revised: 06/29/2023] [Accepted: 07/01/2023] [Indexed: 07/06/2023]
Abstract
Social communication and interaction deficits, memory impairment, and anxiety-like behavior are characterized in many people identified with autism spectrum disorder (ASD). A thorough understanding of the specific aspects that contribute to the deficiencies associated with ASD can aid research into the etiology of the disorder while also providing targets for more effective intervention. As part of the ASD pathophysiology, alterations in synaptogenesis and abnormal network connections were seen in high-order brain areas, which control social behavior and communication. The early emergence of microglia during nervous system development may contribute to synaptic dysfunction and the pathobiology of ASD. Since aquaporin-4 (AQP4) appears to be required for the basic procedures of synapse activation, certain behavioral and cognitive impairments as well as disturbance in water homeostasis might likely arise from AQP4 deficiency. Here, through the measurement of the water content of the hippocampus and behavioral experiments we aim to explore the contribution of astrocytic AQP4 to the autism-like behavior induced by prenatal valproic acid (VPA) exposure and whether inhibition of AQP4 per se can induce autistic-like behavior in control rats. Microinjection of TGN-020 (10µM, i.c.v), a specific AQP4 inhibitor, for 7 successive days before behavioral tasks from postnatal day 28 to 35 revealed that inhibition of AQP4 in the control offspring caused lower social interaction and locomotor activity, higher anxiety, and decreased ability to recognize novel objects, very similar to the behavioral changes observed in offspring prenatally exposed to VPA. However, VPA-exposed offspring treated with TGN-020, showed no further remarkable behavioral impairments than those detected in the autistic-like rats. Furthermore, both control offspring treated with TGN-020 and offspring exposed to VPA had a considerable accumulation of water in their hippocampi. But AQP4 inhibition did not affect the water status of the autistic-like rats. The findings of this study revealed that control offspring exhibited similar hippocampal water retention and behavioral impairments that were observed in maternal VPA-exposed offspring following inhibition of astrocytic AQP4, whereas, in autistic-like rats, it did not produce any significant change in water content and behaviors. Findings suggest that AQP4 deficiency could be associated with autistic disorder and may be a potential pharmaceutical target for treating autism in the future.
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Affiliation(s)
- Shima Davoudi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mona Rahdar
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Narges Hosseinmardi
- Neurophysiology Research Center, Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Gila Behzadi
- Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mahyar Janahmadi
- Neuroscience Research Center, Department of Physiology, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
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Zhou L, Li Y, Wang M, Han W, Chen Q, Zhang J, Sun B, Fan Y. Disruption of α-Synuclein proteostasis in the striatum and midbrain of long-term ovariectomized female mice. Neuroscience 2023:S0306-4522(23)00224-5. [PMID: 37257555 DOI: 10.1016/j.neuroscience.2023.05.013] [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: 01/13/2023] [Revised: 05/09/2023] [Accepted: 05/15/2023] [Indexed: 06/02/2023]
Abstract
Epidemiological studies have demonstrated that women are less susceptible to Parkinson's disease (PD) than men. Estrogen exposure is hypothesized to confer protection against dopaminergic neuronal loss in patients with PD. Although the accumulation and propagation of α-synuclein (α-Syn) are closely linked to the clinical progression of PD, no relevant research has examined whether α-Syn proteostasis in the brain is altered in women after menopause. In this study, we established long-term ovariectomized (OVX) mice to simulate late post-menopause and investigated the expression and aggregation of α-Syn following the ovariectomy procedure. We observed that the OVX mice exhibited a significant increase in the expression and aggregation of α-Syn in the striatum and midbrain accompanied by impaired motor performance at 3 months after ovariectomy. The accumulation of α-Syn did not result in a significant loss of nigral dopaminergic neurons but did enhance autophagy and neuroglial activation. These findings imply that menopause may disrupt α-Syn proteostasis and exacerbate the accumulation of α-Syn in the basal ganglia circuit.
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Affiliation(s)
- Linfeng Zhou
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Yun Li
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Min Wang
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Wenjing Han
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Qiang Chen
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China
| | - Ji Zhang
- Division of Clinical Pharmacy, Department of Pharmacy, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu 210029, China
| | - Bo Sun
- Department of Neurology, the Affiliated Huaian No.1 People's Hospital of Nanjing Medical University, Huai'an, Jiangsu 223300, China; Department of Neurology, the Huaian Clinical College of Xuzhou Medical University, Huai'an, Jiangsu 223300, China.
| | - Yi Fan
- Neuroprotective Drug Discovery Center of Nanjing Medical University, Department of Pharmacology, Nanjing Medical University, Nanjing, China.
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Czuba-Pakuła E, Głowiński S, Wójcik S, Lietzau G, Zabielska-Kaczorowska M, Kowiański P. The extent of damage to the blood-brain barrier in the hypercholesterolemic LDLR -/-/Apo E -/- double knockout mice depends on the animal's age, duration of pathology and brain area. Mol Cell Neurosci 2023; 125:103860. [PMID: 37182573 DOI: 10.1016/j.mcn.2023.103860] [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: 03/08/2023] [Revised: 04/30/2023] [Accepted: 05/08/2023] [Indexed: 05/16/2023] Open
Abstract
One of the effects of hypercholesterolemia (Hch) exerted on the central nervous system (CNS) is damage to the blood-brain barrier (BBB). Increased permeability of BBB results from structural changes in the vascular wall, loss of the tight junctions and barrier function, as well as alterations in the concentration of proteins located in the layers of the vascular wall. These changes occur in the course of metabolic and neurodegenerative diseases. The important role in the course of these processes is attributed to agrin, matrix metalloproteinase-9, and aquaporin-4. In this study, we aimed to determine: 1) the extent of Hch-induced damage to the BBB during maturation, and 2) the distribution of the above-mentioned markers in the vascular wall. Immunohistochemical staining and confocal microscopy were used for vascular wall protein assessment. The size of BBB damage was studied based on perivascular leakage of fluorescently labeled dextran. Three- and twelve-month-old male LDLR-/-/Apo E-/- double knockout mice (EX) developing Hch were used in the study. Age-matched male wild-type (WT) C57BL/6 mice were used as a control group. Differences in the concentration of studied markers coexisted with BBB disintegration, especially in younger mice. A relationship between the maturation of the vascular system and reduction of the BBB damage was also observed. We conclude that the extent of BBB permeability depends on animal age, duration of Hch, and brain region. These may explain different susceptibility of various brain areas to Hch, and different presentation of this pathology depending on age and its duration.
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Affiliation(s)
- Ewelina Czuba-Pakuła
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Sebastian Głowiński
- Institute of Health Sciences, Pomeranian University in Słupsk, Bohaterów Westerplatte 64, 76-200 Słupsk, Poland.
| | - Sławomir Wójcik
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Grażyna Lietzau
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland.
| | - Magdalena Zabielska-Kaczorowska
- Department of Physiology, Medical University of Gdańsk, 1 Dębinki Str., 80-211 Gdańsk, Poland; Department of Biochemistry, Medical University of Gdańsk, 1 Dębinki Str., 80-211 Gdańsk, Poland.
| | - Przemysław Kowiański
- Division of Anatomy and Neurobiology, Faculty of Medicine, Medical University of Gdańsk, Dębinki 1, 80-211 Gdańsk, Poland; Institute of Health Sciences, Pomeranian University in Słupsk, Bohaterów Westerplatte 64, 76-200 Słupsk, Poland.
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10
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Yılmaz H, Şengelen A, Demirgan S, Paşaoğlu HE, Çağatay M, Erman İE, Bay M, Güneyli HC, Önay-Uçar E. Acutely increased aquaporin-4 exhibits more potent protective effects in the cortex against single and repeated isoflurane-induced neurotoxicity in the developing rat brain. Toxicol Mech Methods 2022; 33:279-292. [PMID: 36127839 DOI: 10.1080/15376516.2022.2127389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
Damage to hippocampus, cerebellum, and cortex associated with cognitive functions due to anesthetic-induced toxicity early in life may cause cognitive decline later. Aquaporin 4 (AQP4), a key protein in waste clearance pathway of brain, is involved in synaptic plasticity and neurocognition. We investigated the effects of single and repeated isoflurane (Iso) anesthesia on AQP4 levels and brain damage. Postnatal-day (P)7 Wistar albino rats were randomly assigned to Iso or Control (C) groups. For single-exposure, pups were exposed to 1.5% Iso in 30% oxygenated-air for 3-h at P7 (Iso1). For repeated-exposure, pups were exposed to Iso for 3 days, 3-h each day, at 1-day intervals (P7 + 9+11) starting at P7 (Iso3). C1 and C3 groups received only 30% oxygenated-air. Based on HE-staining and immunoblotting (Bax/Bcl-2, cleaved-caspase3 and PARP1) analyses, Iso exposures caused a higher degree of apoptosis in hippocampus. Anesthesia increased 4HNE, oxidative stress marker; the highest ROS accumulation was determined in cerebellum. Increased inflammation (TNF-α, NF-κB) was detected. Multiple Iso-exposures caused more significant damage than single exposure. Moreover, 4HNE and TNF-α contributed synergistically to Iso-induced neurotoxicity. After anesthesia, higher expression of AQP4 was detected in cortex than hippocampus and cerebellum. There was an inverse correlation between increased AQP4 levels and apoptosis/ROS/inflammation. Correlation analysis indicated that AQP4 had a more substantial protective profile against oxidative stress than apoptosis. Remarkably, acutely increased AQP4 against Iso exhibited a more potent neuroprotective effect in cortex, especially frontal cortex. These findings promote further research to understand better the mechanisms underlying anesthesia-induced toxicity in the developing brain.
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Affiliation(s)
- Habip Yılmaz
- Department of Public Hospital Services, Istanbul Health Directorate, Istanbul, Turkey
| | - Aslıhan Şengelen
- Department of Molecular Biology and Genetics, Institute of Graduate Studies in Sciences, Istanbul University, Istanbul, Turkey
| | - Serdar Demirgan
- Department of Molecular Biology and Genetics, Institute of Graduate Studies in Sciences, Istanbul University, Istanbul, Turkey.,Clinic of Anesthesiology and Reanimation, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - Hüsniye Esra Paşaoğlu
- Department of Pathology, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - Melike Çağatay
- Clinic of Anesthesiology and Reanimation, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - İbrahim Emre Erman
- Clinic of Anesthesiology and Reanimation, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - Mehmet Bay
- Clinic of Anesthesiology and Reanimation, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - Hasan Cem Güneyli
- Clinic of Anesthesiology and Reanimation, University of Health Sciences, Bağcılar Training and Research Hospital, Istanbul, Turkey
| | - Evren Önay-Uçar
- Department of Molecular Biology and Genetics, Faculty of Science, Istanbul University, Istanbul, Turkey
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11
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Schacke S, Kirkpatrick J, Stocksdale A, Bauer R, Hagel C, Riecken LB, Morrison H. Ezrin deficiency triggers glial fibrillary acidic protein upregulation and a distinct reactive astrocyte phenotype. Glia 2022; 70:2309-2329. [PMID: 35929192 DOI: 10.1002/glia.24253] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Revised: 07/12/2022] [Accepted: 07/15/2022] [Indexed: 01/02/2023]
Abstract
Astrocytes are increasingly being recognized as contributors to physiological brain function and behavior. Astrocytes engage in glia-synaptic interactions through peripheral astrocyte processes, thus modulating synaptic signaling, for example, by handling glutamate removal from the synaptic cleft and (re)provision to axonal terminals. Peripheral astrocyte processes are ultrafine membrane protrusions rich in the membrane-to-actin cytoskeleton linker Ezrin, an essential component of in vitro filopodia formation and in vivo peripheral astrocyte process motility. Consequently, it has been postulated that Ezrin significantly contributes to neurodevelopment as well as astrocyte functions within the adult brain. However, while Ezrin has been studied in vitro within cultured primary astrocytes, in vivo studies on the role of Ezrin in astrocytes remain to be conducted and consequences of its depletion to be studied. Here, we investigated consequences of Ezrin deletion in the mouse brain starting from early neuronal specification. While Ezrin knockout did not impact prenatal cerebral cortex development, behavioral phenotyping depicted reduced exploratory behavior. Starting with postnatal appearance of glia cells, Ezrin was verified to remain predominantly expressed in astrocytes. Proteome analysis of Ezrin deficient astrocytes revealed alterations in glutamate and ion homeostasis, metabolism and cell morphology - important processes for synaptic signal transmission. Notably, Ezrin deletion in astrocytes provoked (GFAP) glial fibrillary acidic protein upregulation - a marker of astrocyte activation and reactive astrogliosis. However, this spontaneous, reactive astrogliosis exhibited proteome changes distinct from ischemic-induced reactive astrogliosis. Moreover, in experimental ischemic stroke, Ezrin knockout mice displayed reduced infarct volume, indicating a protective effect of the Ezrin deletion-induced changes and astrogliosis.
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Affiliation(s)
- Stephan Schacke
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | | | - Amy Stocksdale
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Reinhard Bauer
- Institute of Molecular Cell Biology, CMB, Jena University Hospital, Jena, Germany
| | - Christian Hagel
- Institute of Neuropathology, University Medical Center Hamburg-Eppendorf, Hamburg, Germany
| | | | - Helen Morrison
- Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany.,Faculty of Biological Sciences, Friedrich-Schiller University, Jena, Germany
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12
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Rana T, Behl T, Shamsuzzaman M, Singh S, Sharma N, Sehgal A, Alshahrani AM, Aldahish A, Chidambaram K, Dailah HG, Bhatia S, Bungau S. Exploring the role of astrocytic dysfunction and AQP4 in depression. Cell Signal 2022; 96:110359. [PMID: 35597427 DOI: 10.1016/j.cellsig.2022.110359] [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: 04/30/2022] [Revised: 05/15/2022] [Accepted: 05/15/2022] [Indexed: 11/20/2022]
Abstract
Aquaporin-4 (AQP4) is the water regulating channel found in the terminal processes of astrocytes in the brain and is implicated in regulating the astrocyte functions, whereas in neuropathologies, AQP4 performs an important role in astrocytosis and release of proinflammatory cytokines. However, several findings have revealed the modulation of the AQP4 water channel in the etiopathogenesis of various neuropsychiatric diseases. In the current article, we have summarized the recent studies and highlighted the implication of astrocytic dysfunction and AQP4 in the etiopathogenesis of depressive disorder. Most of the studies have measured the AQP4 gene or protein expression in the brain regions, particularly the locus coeruleus, choroid plexus, prefrontal cortex, and hippocampus, and found that in these brain regions, AQP4 gene expression decreased on exposure to chronic mild stress. Few studies also measured the peripheral AQP4 mRNA expression in the blood and AQP4 autoantibodies in the blood serum and revealed no change in the depressed patients in comparison with normal individuals.
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Affiliation(s)
- Tarapati Rana
- Chitkara College of Pharmacy, Chitkara University, Punjab, India; Government Pharmacy College, Seraj, Mandi, Himachal Pradesh, India
| | - Tapan Behl
- Chitkara College of Pharmacy, Chitkara University, Punjab, India.
| | - Md Shamsuzzaman
- Department of Pharmaceutical Sciences, College of Pharmacy, Shaqra University, Saudi Arabia
| | - Sukhbir Singh
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Neelam Sharma
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Aayush Sehgal
- Chitkara College of Pharmacy, Chitkara University, Punjab, India
| | - Asma M Alshahrani
- Department of Clinical Pharmacy, Faculty of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Afaf Aldahish
- Department of Pharmacology, Faculty of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Kumarappan Chidambaram
- Department of Pharmacology, Faculty of Pharmacy, King Khalid University, Abha, Saudi Arabia
| | - Hamad Ghaleb Dailah
- Research and Scientific Studies Unit, College of Nursing, Jazan University, Jazan, Saudi Arabia
| | - Saurabh Bhatia
- Natural & Medical Sciences Research Centre, University of Nizwa, Nizwa, Oman; School of Health Science, University of Petroleum and Energy Studies, Dehradun, Uttarakhand, India
| | - Simona Bungau
- Department of Pharmacy, Faculty of Medicine of Pharmacy, University of Oradea, Oradea, Romania
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13
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Yang S, Kong XY, Hu T, Ge YJ, Li XY, Chen JT, He S, Zhang P, Chen GH. Aquaporin-4, Connexin-30, and Connexin-43 as Biomarkers for Decreased Objective Sleep Quality and/or Cognition Dysfunction in Patients With Chronic Insomnia Disorder. Front Psychiatry 2022; 13:856867. [PMID: 35401278 PMCID: PMC8989729 DOI: 10.3389/fpsyt.2022.856867] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/21/2022] [Indexed: 12/04/2022] Open
Abstract
OBJECTIVES To examine serum concentrations of aquaporin-4 (AQP4), connexin-30 (CX30), connexin-43 (CX43), and their correlations with cognitive function in the patients with chronic insomnia disorder (CID). METHODS We enrolled 76 subjects with CID and 32 healthy controls (HCs). Serum levels of AQP4, CX30, and CX43 were measured by enzyme-linked immunosorbent assays. Sleep quality was assessed with the Pittsburgh Sleep Quality Index (PSQI) and polysomnography, and mood was evaluated with 17-item Hamilton Depression Rating Scale and 14-item Hamilton Anxiety Rating Scale. Cognitive function was evaluated by the Chinese-Beijing Version of Montreal Cognitive Assessment (MoCA-C) and Nine Box Maze Test. RESULTS The serum levels of AQP4, CX43, and CX30 were significantly reduced in the CID group compared to the HCs. Partial correlation analysis showed that the biomarkers showed no significant correlations with PSQI score, AHI, ODI and TS90, but AQP4, CX43, and CX30 were positively associated with the percentage and total time of slow wave sleep in the CID group. Serum concentrations of AQP4 and CX30 were positively associated with MoCA-C score in the CID group, and AQP4 level negatively correlated with spatial working memory errors. CONCLUSIONS Subjects with CID patients have decreased serum levels of AQP4, CX30, and CX43 indicating astrocyte dysfunction, which could be related to poor objective sleep quality and/or cognition dysfunction.
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Affiliation(s)
- Shuai Yang
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Xiao-Yi Kong
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Ting Hu
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Yi-Jun Ge
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Xue-Yan Li
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Jun-Tao Chen
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Shuo He
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Ping Zhang
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
| | - Gui-Hai Chen
- Department of Neurology (Sleep Disorders), The Affiliated Chaohu Hospital of Anhui Medical University, Hefei, China
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14
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Marazuela P, Bonaterra-Pastra A, Faura J, Penalba A, Pizarro J, Pancorbo O, Rodríguez-Luna D, Vert C, Rovira A, Pujadas F, Freijo MM, Tur S, Martínez-Zabaleta M, Cardona Portela P, Vera R, Lebrato-Hernández L, Arenillas JF, Pérez-Sánchez S, Montaner J, Delgado P, Hernández-Guillamon M. Circulating AQP4 Levels in Patients with Cerebral Amyloid Angiopathy-Associated Intracerebral Hemorrhage. J Clin Med 2021; 10:jcm10050989. [PMID: 33801197 PMCID: PMC7957864 DOI: 10.3390/jcm10050989] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2021] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 12/27/2022] Open
Abstract
Cerebral amyloid angiopathy (CAA) is a major cause of lobar intracerebral hemorrhage (ICH) in elderly patients. Growing evidence suggests a potential role of aquaporin 4 (AQP4) in amyloid-beta-associated diseases, including CAA pathology. Our aim was to investigate the circulating levels of AQP4 in a cohort of patients who had suffered a lobar ICH with a clinical diagnosis of CAA. AQP4 levels were analyzed in the serum of 60 CAA-related ICH patients and 19 non-stroke subjects by enzyme-linked immunosorbent assay (ELISA). The CAA–ICH cohort was divided according to the time point of the functional outcome evaluation: mid-term (12 ± 18.6 months) and long-term (38.5 ± 32.9 months) after the last ICH. Although no differences were found in AQP4 serum levels between cases and controls, lower levels were found in CAA patients presenting specific hemorrhagic features such as ≥2 lobar ICHs and ≥5 lobar microbleeds detected by magnetic resonance imaging (MRI). In addition, CAA-related ICH patients who presented a long-term good functional outcome had higher circulating AQP4 levels than subjects with a poor outcome or controls. Our data suggest that AQP4 could potentially predict a long-term functional outcome and may play a protective role after a lobar ICH.
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Affiliation(s)
- Paula Marazuela
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Anna Bonaterra-Pastra
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Júlia Faura
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Anna Penalba
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Jesús Pizarro
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Olalla Pancorbo
- Stroke Unit, Department of Neurology, Vall d’Hebron Hospital, 08035 Barcelona, Spain; (O.P.); (D.R.-L.)
| | - David Rodríguez-Luna
- Stroke Unit, Department of Neurology, Vall d’Hebron Hospital, 08035 Barcelona, Spain; (O.P.); (D.R.-L.)
| | - Carla Vert
- Neuroradiology, Department of Radiology, Vall d’Hebron Hospital, 08035 Barcelona, Spain; (C.V.); (A.R.)
| | - Alex Rovira
- Neuroradiology, Department of Radiology, Vall d’Hebron Hospital, 08035 Barcelona, Spain; (C.V.); (A.R.)
| | - Francesc Pujadas
- Dementia Unit, Neurology Department, Vall d’Hebron Hospital, 08035 Barcelona, Spain;
| | - M. Mar Freijo
- Neurovascular Group, Biocruces Health Research Institute, 48903 Barakaldo, Spain;
| | - Silvia Tur
- Neurology, Son Espases University Hospital, 07120 Balearic Islands, Spain;
| | | | - Pere Cardona Portela
- Department of Neurology, Bellvitge University Hospital, L’Hospitalet de Llobregat, 08907 Barcelona, Spain;
| | - Rocío Vera
- Stroke Unit, Department of Neurology, Ramon y Cajal University Hospital, 28034 Madrid, Spain;
| | | | - Juan F. Arenillas
- Stroke Program, Department of Neurology, Hospital Clínico Universitario, 47003 Valladolid, Spain;
- Clinical Neurosciences Research Group, Department of Medicine, University of Valladolid, 47003 Valladolid, Spain
| | | | - Joan Montaner
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
- Department of Neurology, Virgen Macarena University Hospital, 41009 Sevilla, Spain;
- Stroke Research Program, Institute of Biomedicine of Sevilla, IBiS, Virgen del Rocío University Hospital, University of Sevilla, 41009 Sevilla, Spain
| | - Pilar Delgado
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
| | - Mar Hernández-Guillamon
- Neurovascular Research Laboratory, Vall d’Hebron Research Institute, Universitat Autònoma de Barcelona, 08035 Barcelona, Spain; (P.M.); (A.B.-P.); (J.F.); (A.P.); (J.P.); (J.M.); (P.D.)
- Correspondence:
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15
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Chen T, Lennon VA, Liu YU, Bosco DB, Li Y, Yi MH, Zhu J, Wei S, Wu LJ. Astrocyte-microglia interaction drives evolving neuromyelitis optica lesion. J Clin Invest 2021; 130:4025-4038. [PMID: 32568214 DOI: 10.1172/jci134816] [Citation(s) in RCA: 51] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 04/16/2020] [Indexed: 12/13/2022] Open
Abstract
Neuromyelitis optica (NMO) is a severe inflammatory autoimmune CNS disorder triggered by binding of an IgG autoantibody to the aquaporin 4 (AQP4) water channel on astrocytes. Activation of cytolytic complement has been implicated as the major effector of tissue destruction that secondarily involves myelin. We investigated early precytolytic events in the evolving pathophysiology of NMO in mice by continuously infusing IgG (NMO patient serum-derived or AQP4-specific mouse monoclonal), without exogenous complement, into the spinal subarachnoid space. Motor impairment and sublytic NMO-compatible immunopathology were IgG dose dependent, AQP4 dependent, and, unexpectedly, microglia dependent. In vivo spinal cord imaging revealed a striking physical interaction between microglia and astrocytes that required signaling from astrocytes by the C3a fragment of their upregulated complement C3 protein. Astrocytes remained viable but lost AQP4. Previously unappreciated crosstalk between astrocytes and microglia involving early-activated CNS-intrinsic complement components and microglial C3a receptor signaling appears to be a critical driver of the precytolytic phase in the evolving NMO lesion, including initial motor impairment. Our results indicate that microglia merit consideration as a potential target for NMO therapeutic intervention.
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Affiliation(s)
| | - Vanda A Lennon
- Department of Neurology.,Department of Immunology, and.,Department of Laboratory Medicine/Pathology, Mayo Clinic, Rochester, Minnesota, USA
| | | | | | | | | | | | - Shihui Wei
- Department of Ophthalmology, Chinese PLA General Hospital, Beijing, China
| | - Long-Jun Wu
- Department of Neurology.,Department of Immunology, and.,Department of Neuroscience, Mayo Clinic, Jacksonville, Florida, USA
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16
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Zhang H, Chen J, Wang H, Lu X, Li K, Yang C, Wu F, Xu Z, Nie H, Ding B, Guo Z, Li Y, Wang J, Li Y, Dai Z. Serum Metabolomics Associating With Circulating MicroRNA Profiles Reveal the Role of miR-383-5p in Rat Hippocampus Under Simulated Microgravity. Front Physiol 2020; 11:939. [PMID: 33013433 PMCID: PMC7461998 DOI: 10.3389/fphys.2020.00939] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Accepted: 07/13/2020] [Indexed: 01/08/2023] Open
Abstract
Microgravity impacts various aspects of human health. Yet the mechanisms of spaceflight-induced health problems are not elucidated. Here, we mapped the fusion systemic analysis of the serum metabolome and the circulating microRNAome in a hindlimb unloading rat model to simulate microgravity. The response of serum metabolites and microRNAs to simulated microgravity was striking. Integrated pathway analysis of altered serum metabolites and target genes of the significantly altered circulating miRNAs with Integrated Molecular Pathway-Level Analysis (IMPaLA) software was mainly suggestive of modulation of neurofunctional signaling pathways. Particularly, we revealed significantly increased miR-383-5p and decreased aquaporin 4 (AQP4) in the hippocampus. Using rabies virus glycoprotein-modified exosomes, delivery of miR-383-5p inhibited the expression of AQP4 not only in rat C6 glioma cells in vitro but also in the hippocampus in vivo. Using bioinformatics to map the crosstalk between the circulating metabolome and miRNAome could offer opportunities to understand complex biological systems under microgravity. Our present results suggested that the change of miR-383-5p level and its regulation of target gene AQP4 was one of the potential molecular mechanisms of microgravity-induced cognitive impairment in the hippocampus.
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Affiliation(s)
- Hongyu Zhang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Jian Chen
- Institute of Cell and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Hailong Wang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Xin Lu
- School of Life Sciences and Technology, Harbin Institute of Technology, Harbin, China
| | - Kai Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Chao Yang
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Feng Wu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Zihan Xu
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Huan Nie
- School of Life Sciences and Technology, Harbin Institute of Technology, Harbin, China
| | - Bai Ding
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Zhifeng Guo
- Institute of Cell and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yu Li
- School of Life Sciences and Technology, Harbin Institute of Technology, Harbin, China
| | - Jinfu Wang
- Institute of Cell and Developmental Biology, College of Life Sciences, Zhejiang University, Hangzhou, China
| | - Yinghui Li
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
| | - Zhongquan Dai
- State Key Laboratory of Space Medicine Fundamentals and Application, China Astronaut Research and Training Center, Beijing, China
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17
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Inhibition of Aquaporin 4 Decreases Amyloid Aβ40 Drainage Around Cerebral Vessels. Mol Neurobiol 2020; 57:4720-4734. [PMID: 32783141 PMCID: PMC7515968 DOI: 10.1007/s12035-020-02044-8] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2020] [Accepted: 07/24/2020] [Indexed: 01/17/2023]
Abstract
Aquaporin-4 (AQP4) is located mainly in the astrocytic end-feet around cerebral blood vessels and regulates ion and water homeostasis in the brain. While deletion of AQP4 is shown to reduce amyloid-β (Aβ) clearance and exacerbate Aβ peptide accumulation in plaques and vessels of Alzheimer's disease mouse models, the mechanism and clearing pathways involved are debated. Here, we investigated how inhibiting the function of AQP4 in healthy male C57BL/6 J mice impacts clearance of Aβ40, the more soluble Aβ isoform. Using two-photon in vivo imaging and visualizing vessels with Sulfurodamine 101 (SR101), we first showed that Aβ40 injected as a ≤ 0.5-μl volume in the cerebral cortex diffused rapidly in parenchyma and accumulated around blood vessels. In animals treated with the AQP4 inhibitor TGN-020, the perivascular Aβ40 accumulation was significantly (P < 0.001) intensified by involving four times more vessels, thus suggesting a generalized clearance defect associated with vessels. Increasing the injecting volume to ≥ 0.5 ≤ 1 μl decreased the difference of Aβ40-positive vessels observed in non-treated and AQP4 inhibitor-treated animals, although the difference was still significant (P = 0.001), suggesting that larger injection volumes could overwhelm intramural vascular clearance mechanisms. While both small and large vessels accumulated Aβ40, for the ≤ 0.5-μl volume group, the average diameter of the Aβ40-positive vessels tended to be larger in control animals compared with TGN-020-treated animals, although the difference was non-significant (P = 0.066). Using histopathology and ultrastructural microscopy, no vascular structural change was observed after a single massive dose of TGN-020. These data suggest that AQP4 deficiency is directly involved in impaired Aβ brain clearance via the peri-/para-vascular routes, and AQP4-mediated vascular clearance might counteract blood-brain barrier abnormalities and age-related vascular amyloidopathy.
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18
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Woo J, Jang MW, Lee J, Koh W, Mikoshiba K, Lee CJ. The molecular mechanism of synaptic activity-induced astrocytic volume transient. J Physiol 2020; 598:4555-4572. [PMID: 32706443 DOI: 10.1113/jp279741] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2020] [Accepted: 07/20/2020] [Indexed: 12/16/2022] Open
Abstract
KEY POINTS Neuronal activity causes astrocytic volume change via K+ uptake through TREK-1 containing two-pore domain potassium channels. The volume transient is terminated by Cl- efflux through the Ca2+ -activated anion channel BEST1. The source of the Ca2+ required to open BEST1 appears to be the stretch-activated TRPA1 channel. Intense neuronal activity is synaptically coupled with a physical change in astrocytes via volume transients. ABSTRACT The brain volume changes dynamically and transiently upon intense neuronal activity through a tight regulation of ion concentrations and water movement across the plasma membrane of astrocytes. We have recently demonstrated that an intense neuronal activity and subsequent astrocytic AQP4-dependent volume transient are critical for synaptic plasticity and memory. We have also pharmacologically demonstrated a functional coupling between synaptic activity and the astrocytic volume transient. However, the precise molecular mechanisms of how intense neuronal activity and the astrocytic volume transient are coupled remain unclear. Here we utilized an intrinsic optical signal imaging technique combined with fluorescence imaging using ion sensitive dyes and molecular probes and electrophysiology to investigate the detailed molecular mechanisms in genetically modified mice. We report that a brief synaptic activity induced by a train stimulation (20 Hz, 1 s) causes a prolonged astrocytic volume transient (80 s) via K+ uptake through TREK-1 containing two-pore domain potassium (K2P) channels, but not Kir4.1 or NKCC1. This volume change is terminated by Cl- efflux through the Ca2+ -activated anion channel BEST1, but not the volume-regulated anion channel TTYH. The source of the Ca2+ required to open BEST1 appears to be the stretch-activated TRPA1 channel in astrocytes, but not IP3 R2. In summary, our study identifies several important astrocytic ion channels (AQP4, TREK-1, BEST1, TRPA1) as the key molecules leading to the neuronal activity-dependent volume transient in astrocytes. Our findings reveal new molecular and cellular mechanisms for the synaptic coupling of intense neuronal activity with a physical change in astrocytes via volume transients.
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Affiliation(s)
- Junsung Woo
- Center for Glia-Neuron Interaction, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Minwoo Wendy Jang
- KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea.,Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea
| | - Jaekwang Lee
- Center for Glia-Neuron Interaction, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea
| | - Wuhyun Koh
- Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea.,Department of Neuroscience, Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
| | - Katsuhiko Mikoshiba
- Laboratory for Developmental Biology, RIKEN Brain Science Institute, Hirosawa 2-1, Wako, Saitama, 351-0198, Japan
| | - C Justin Lee
- Center for Glia-Neuron Interaction, Korea Institute of Science and Technology (KIST), Seoul, 02792, Republic of Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul, 02841, Republic of Korea.,Center for Cognition and Sociality, Institute for Basic Science (IBS), Daejeon, 34126, Republic of Korea.,Department of Neuroscience, Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea
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19
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Ding Y, Liu J, Xu Y, Dong X, Shao B. Evolutionary Adaptation of Aquaporin-4 in Yak ( Bos grunniens) Brain to High-Altitude Hypoxia of Qinghai-Tibetan Plateau. High Alt Med Biol 2020; 21:167-175. [PMID: 32155353 DOI: 10.1089/ham.2019.0076] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Background: In high-altitude animals, brain cell resilience against hypoxia stress is one critical evolutionary step that has promoted individual survival and species adaptation to the environment. Aquaporin-4 (AQP4) is implicated in a number of physiopathological processes, particularly in the development of brain edema, and other functions such as the regulation of extracellular space volume, potassium buffering, waste clearance, and calcium signaling. Still, the role of AQP4 in the adaptation to high-altitude hypoxia remains unknown. The yak (Bos grunniens) is the only large mammal that is currently known to have adapted to the high-altitude hypoxic environment of the Qinghai-Tibet Plateau (>4000 m above sea level). Methods: In this study, we cloned the complementary DNA (cDNA) for yak AQP4 and analyzed structural differences of AQP4 between yak and cattle. We used reverse transcription quantitative polymerase chain reaction and western blot to investigate whether the expression of AQP4 mRNA and protein was different in brain of yak and cattle. In addition, immunohistochemistry was use to analyze the localization and expression of AQP4 in brain of yak and cattle. Results: Immunohistochemical results have shown that AQP4 is expressed in many regions of the yak brain, and both protein and messenger RNA (mRNA) levels are significantly lower than those of low-altitude cattle (Bos taurus). Phylogenetic analysis revealed that yak AQP4 is evolutionarily conserved. Interestingly, a substitution of Ala (cattle) to Ser in position 82, and eight additional amino acid residues composing an α-helix region are present in yak AQP4 protein. These sequence modifications potentially modulate the function of AQP4 in distinct environments. Conclusions: Our findings suggest that AQP4 may have an important role in the resistance to cerebral edema through low expression and maintenance of normal physiological function in the yak brain.
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Affiliation(s)
- Yanping Ding
- School of Life Sciences, Northwest Normal University, Lanzhou, P.R. China
| | - Jianfeng Liu
- School of Life Sciences, Lanzhou University, Lanzhou, P.R. China
| | - Yuanqing Xu
- School of Life Sciences, Lanzhou University, Lanzhou, P.R. China
| | - Xiaoqing Dong
- School of Life Sciences, Northwest Normal University, Lanzhou, P.R. China
| | - Baoping Shao
- School of Life Sciences, Lanzhou University, Lanzhou, P.R. China
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20
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Wang C, Wu Q, Wang Z, Hu L, Marshall C, Xiao M. Aquaporin 4 knockout increases complete freund's adjuvant-induced spinal central sensitization. Brain Res Bull 2020; 156:58-66. [DOI: 10.1016/j.brainresbull.2020.01.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 12/30/2019] [Accepted: 01/03/2020] [Indexed: 01/07/2023]
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21
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Demirgan S, Akyol O, Temel Z, Şengelen A, Pekmez M, Demirgan R, Sevdi MS, Erkalp K, Selcan A. Isoflurane exposure in infant rats acutely increases aquaporin 4 and does not cause neurocognitive impairment. Bosn J Basic Med Sci 2019; 19:257-264. [PMID: 30821219 DOI: 10.17305/bjbms.2019.4116] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 02/19/2019] [Indexed: 11/16/2022] Open
Abstract
Isoflurane is commonly used in pediatric population, but its mechanism of action in cognition is unclear. Aquaporin 4 (AQP4) regulates water content in blood, brain, and cerebrospinal fluid. Various studies have provided evidence for the role of AQP4 in synaptic plasticity and neurocognition. In this study, we aimed to determine whether a prolonged exposure to isoflurane in infant rats is associated with cognition and what effect this exposure has on AQP4 expression. Ten-day-old [postnatal day (P) 10] Wistar albino rats were randomly allocated to isoflurane group (n = 32; 1.5% isoflurane in 50% oxygen for 6 hours) or control group (n = 32; only 50% oxygen for 6 hours). Acute (P11) and long-term (P33) effects of 6-hour anesthetic isoflurane exposure on AQP4 expression were analyzed in whole brains of P11 and P33 rats by RT-qPCR and Western blot. Spatial learning and memory were assessed on P28 to P33 days by Morris Water Maze (MWM) test. The analysis revealed that isoflurane increased acutely both mRNA (~4.5 fold) and protein (~90%) levels of AQP4 in P11 rats compared with control group. The increasing levels of AQP4 in P11 were not observed in P33 rats. Also, no statistically significant change between isoflurane and control groups was observed in the latency to find the platform during MWM training and probe trial. Our results indicate that a single exposure to isoflurane anesthesia does not influence cognition in infant rats. In this case, acutely increased AQP4 after isoflurane anesthesia may have a protective role in neurocognition.
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Affiliation(s)
- Serdar Demirgan
- T.C. Health Ministry, Health Sciences University, Bagcilar Training and Research Hospital, Anesthesiology and Reanimation Clinic; Department of Molecular Biology and Genetics, Institute of Graduate Studies in Sciences, Istanbul University, Istanbul, Turkey.
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22
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Kobylarek D, Iwanowski P, Lewandowska Z, Limphaibool N, Szafranek S, Labrzycka A, Kozubski W. Advances in the Potential Biomarkers of Epilepsy. Front Neurol 2019; 10:685. [PMID: 31312171 PMCID: PMC6614180 DOI: 10.3389/fneur.2019.00685] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2019] [Accepted: 06/12/2019] [Indexed: 12/11/2022] Open
Abstract
Epilepsy is a group of chronic neurological disorders characterized by recurrent, spontaneous, and unpredictable seizures. It is one of the most common neurological disorders, affecting tens of millions of people worldwide. Comprehensive studies on epilepsy in recent decades have revealed the complexity of epileptogenesis, in which immunological processes, epigenetic modifications, and structural changes in neuronal tissues have been identified as playing a crucial role. This review discusses the recent advances in the biomarkers of epilepsy. We evaluate the possible molecular background underlying the clinical changes observed in recent studies, focusing on therapeutic investigations, and the evidence of their safety and efficacy in the human population. This article reviews the pathophysiology of epilepsy, including recent reports on the effects of oxidative stress and hypoxia, and focuses on specific biomarkers and their clinical implications, along with further perspectives in epilepsy research.
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Affiliation(s)
- Dominik Kobylarek
- Department of Neurology, Poznan University of Medical Sciences, Poznan, Poland
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23
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Oertel FC, Schließeit J, Brandt AU, Paul F. Cognitive Impairment in Neuromyelitis Optica Spectrum Disorders: A Review of Clinical and Neuroradiological Features. Front Neurol 2019; 10:608. [PMID: 31258505 PMCID: PMC6587817 DOI: 10.3389/fneur.2019.00608] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 05/22/2019] [Indexed: 12/21/2022] Open
Abstract
Neuromyelitis optica spectrum disorders (NMOSD) are mostly relapsing autoimmune inflammatory disorders of the central nervous system (CNS) with optic neuritis, myelitis, and brainstem syndromes as clinical hallmarks. With a reported prevalence of up to 70%, cognitive impairment is frequent, but often unrecognized and an insufficiently treated burden of the disease. The most common cognitive dysfunctions are decline in attention and memory performance. Magnetic resonance imaging can be used to access structural correlates of neuropsychological disorders. Cognitive impairment is not only a highly underestimated symptom in patients with NMOSD, but potentially also a clinical correlate of attack-independent changes in NMOSD, which are currently under debate. This article reviews cognitive impairment in NMOSD and discusses associations between structural changes of the CNS and cognitive deficits.
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Affiliation(s)
- Frederike Cosima Oertel
- NeuroCure Clinical Research Center, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin and Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Jana Schließeit
- NeuroCure Clinical Research Center, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin and Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Faculty of Psychology and Neuroscience, Maastricht University, Maastricht, Netherlands
| | - Alexander U Brandt
- NeuroCure Clinical Research Center, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin and Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Department of Neurology, University of California, Irvine, Irvine, CA, United States
| | - Friedemann Paul
- NeuroCure Clinical Research Center, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany.,Experimental and Clinical Research Center, Max-Delbrück-Centrum für Molekulare Medizin and Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany.,Department of Neurology, Berlin Institute of Health, Charité - Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Berlin, Germany
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24
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Kim YK, Nam KI, Song J. The Glymphatic System in Diabetes-Induced Dementia. Front Neurol 2018; 9:867. [PMID: 30429819 PMCID: PMC6220044 DOI: 10.3389/fneur.2018.00867] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2018] [Accepted: 09/26/2018] [Indexed: 12/14/2022] Open
Abstract
The glymphatic system has emerged as an important player in central nervous system (CNS) diseases, by regulating the vasculature impairment, effectively controlling the clearance of toxic peptides, modulating activity of astrocytes, and being involved in the circulation of neurotransmitters in the brain. Recently, several studies have indicated decreased activity of the glymphatic pathway under diabetes conditions such as in insulin resistance and hyperglycemia. Furthermore, diabetes leads to the disruption of the blood-brain barrier and decrease of apolipoprotein E (APOE) expression and the secretion of norepinephrine in the brain, involving the impairment of the glymphatic pathway and ultimately resulting in cognitive decline. Considering the increased prevalence of diabetes-induced dementia worldwide, the relationship between the glymphatic pathway and diabetes-induced dementia should be investigated and the mechanisms underlying their relationship should be discussed to promote the development of an effective therapeutic approach in the near future. Here, we have reviewed recent evidence for the relationship between glymphatic pathway dysfunction and diabetes. We highlight that the enhancement of the glymphatic system function during sleep may be beneficial to the attenuation of neuropathology in diabetes-induced dementia. Moreover, we suggest that improving glymphatic system activity may be a potential therapeutic strategy for the prevention of diabetes-induced dementia.
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Affiliation(s)
- Young-Kook Kim
- Department of Biochemistry, Chonnam National University Medical School, Gwangju, South Korea.,Department of Biomedical Sciences, Center for Creative Biomedical Scientists, Chonnam National University, Gwangju, South Korea
| | - Kwang Il Nam
- Department of Anatomy, Chonnam National University Medical School, Gwangju, South Korea
| | - Juhyun Song
- Department of Biomedical Sciences, Center for Creative Biomedical Scientists, Chonnam National University, Gwangju, South Korea.,Department of Anatomy, Chonnam National University Medical School, Gwangju, South Korea
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25
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Astroglial water channel aquaporin 4-mediated glymphatic clearance function: A determined factor for time-sensitive treatment of aerobic exercise in patients with Alzheimer's disease. Med Hypotheses 2018; 119:18-21. [PMID: 30122483 DOI: 10.1016/j.mehy.2018.07.016] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 07/05/2018] [Accepted: 07/21/2018] [Indexed: 11/21/2022]
Abstract
Currently, there are no effective drug therapies for Alzheimer's disease (AD). Thus, exploring new non-pharmacological strategies, including the neuroprotective mechanisms of aerobic exercise, to enhance therapeutic treatment of AD are essential. Previous studies have shown that the beneficial efficiency of aerobic exercise in the prevention and treatment of AD is time-sensitive, but its mechanism is not clear. Recent studies revealed that the water channel protein aquaporin 4 (AQP4) mediates the glymphatic system to clear interstitial solutes, including β-amyloid, from the brain. More recently, voluntary exercise has been shown to promote glymphatic clearance function in mice. However, glymphatic function is reduced in the mid- or late-stage of AD due to the loss of the polarity distribution of AQP4. Based on this, we hypothesized that AQP4-mediated glymphatic system clearance function is a determining factor for time-sensitive treatment of aerobic exercise in patients with AD. While further studies are necessary, the potential results are important for elucidating the new pro-cognitive mechanism of aerobic exercise, but also help to establish a new strategy for treatment of AD via regulation of glymphatic clearance function by targeting AQP4.
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26
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Woo J, Kim JE, Im JJ, Lee J, Jeong HS, Park S, Jung SY, An H, Yoon S, Lim SM, Lee S, Ma J, Shin EY, Han YE, Kim B, Lee EH, Feng L, Chun H, Yoon BE, Kang I, Dager SR, Lyoo IK, Lee CJ. Astrocytic water channel aquaporin-4 modulates brain plasticity in both mice and humans: a potential gliogenetic mechanism underlying language-associated learning. Mol Psychiatry 2018; 23:1021-1030. [PMID: 29565042 DOI: 10.1038/mp.2017.113] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Revised: 03/21/2017] [Accepted: 04/17/2017] [Indexed: 01/04/2023]
Abstract
The role of astrocytes in brain plasticity has not been extensively studied compared with that of neurons. Here we adopted integrative translational and reverse-translational approaches to explore the role of an astrocyte-specific major water channel in the brain, aquaporin-4 (AQP4), in brain plasticity and learning. We initially identified the most prevalent genetic variant of AQP4 (single nucleotide polymorphism of rs162008 with C or T variation, which has a minor allele frequency of 0.21) from a human database (n=60 706) and examined its functionality in modulating the expression level of AQP4 in an in vitro luciferase reporter assay. In the following experiments, AQP4 knock-down in mice not only impaired hippocampal volumetric plasticity after exposure to enriched environment but also caused loss of long-term potentiation after theta-burst stimulation. In humans, there was a cross-sectional association of rs162008 with gray matter (GM) volume variation in cortices, including the vicinity of the Perisylvian heteromodal language area (Sample 1, n=650). GM volume variation in these brain regions was positively associated with the semantic verbal fluency. In a prospective follow-up study (Sample 2, n=45), the effects of an intensive 5-week foreign language (English) learning experience on regional GM volume increase were modulated by this AQP4 variant, which was also associated with verbal learning capacity change. We then delineated in mice mechanisms that included AQP4-dependent transient astrocytic volume changes and astrocytic structural elaboration. We believe our study provides the first integrative evidence for a gliogenetic basis that involves AQP4, underlying language-associated brain plasticity.
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Affiliation(s)
- J Woo
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Neuroscience Program, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - J E Kim
- Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, Republic of Korea.,Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea
| | - J J Im
- Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea.,Interdisciplinary Program in Neuroscience, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - J Lee
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - H S Jeong
- Department of Radiology, Incheon St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - S Park
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - S-Y Jung
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Neuroscience Program, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - H An
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Department of Radiology, University of Washington, Seattle, WA, USA.,Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - S Yoon
- Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea
| | - S M Lim
- Department of Radiology, College of Medicine, Ewha Womans University, Seoul, Republic of Korea
| | - S Lee
- Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea.,Interdisciplinary Program in Neuroscience, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - J Ma
- Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea.,Interdisciplinary Program in Neuroscience, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - E Y Shin
- Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, Republic of Korea.,Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea
| | - Y-E Han
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Neuroscience Program, University of Science and Technology (UST), Daejeon, Republic of Korea
| | - B Kim
- Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea.,Interdisciplinary Program in Neuroscience, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea
| | - E H Lee
- Green Cross Laboratories, Yongin, Republic of Korea
| | - L Feng
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - H Chun
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea
| | - B-E Yoon
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Department of Nanobiomedical Science, Dankook University, Cheonan, Republic of Korea
| | - I Kang
- Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, Republic of Korea.,Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea
| | - S R Dager
- Department of Radiology, University of Washington, Seattle, WA, USA.,Department of Bioengineering, University of Washington, Seattle, WA, USA
| | - I K Lyoo
- Department of Brain and Cognitive Sciences, Scranton College, Ewha Womans University, Seoul, Republic of Korea.,Ewha Brain Institute, Ewha Womans University, Seoul, Republic of Korea.,Graduate School of Pharmaceutical Sciences, Ewha Womans University, Seoul, Republic of Korea
| | - C J Lee
- Center for Neural Science and Functional Connectomics, Korea Institute of Science and Technology (KIST), Seoul, Republic of Korea.,Neuroscience Program, University of Science and Technology (UST), Daejeon, Republic of Korea.,KU-KIST, Graduate School of Convergence Technology, Korea University, Seoul, Republic of Korea
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27
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Cao M, Fang J, Wang X, Wang Y, Duan K, Ye F, Ouyang W, Tong J. Activation of AMP-activated protein kinase (AMPK) aggravated postoperative cognitive dysfunction and pathogenesis in aged rats. Brain Res 2018; 1684:21-29. [PMID: 29408499 DOI: 10.1016/j.brainres.2018.01.027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 01/18/2018] [Accepted: 01/21/2018] [Indexed: 11/17/2022]
Abstract
The upstream signal molecule modulating neuro-inflammation and synaptic changes during the pathogenesis of postoperative cognitive dysfunction (POCD) is still elusive. Here, we examined the effects and mechanisms of energy sensor AMP-activated protein kinase (AMPK) in the pathogenesis of POCD. Our data showed that surgery significantly increased the expression of p-AMPK in aged rats (p < 0.05), but not in adult rats (p > 0.05). Moreover, inhibiting AMPK activation via compound C during operation significantly improved surgery-induced impairment of the learning and memory of aged rats in water maze (p < 0.05). Further mechanism studies showed that corresponding to the impairment of learning and memory after surgery, surgery significantly increased the activation of microglia, decreased the expressions of NR2B and p-NR2B, and increased the expressions of Tau and p-Tau, which also were obviously restored by inhibiting AMPK during operation. In contrast, Inhibiting AMPK activation during operation didn't change ATP level in the hippocampus of aged rats after surgery. These data suggest that surgery induced activation of AMPK in hippocampus in an age-dependent manner. AMPK plays important roles in POCD of aged rats via multiple mechanisms, and is a possible molecular target for the prevention and treatment of POCD.
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Affiliation(s)
- Mengya Cao
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Jiakai Fang
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Xueqin Wang
- Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Yi Wang
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Kaiming Duan
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Feng Ye
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China; Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Wen Ouyang
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China
| | - Jianbin Tong
- Department of Anesthesiology, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China; Center for Experimental Medicine, The Third Xiangya Hospital, Central South University, Changsha, Hunan, PR China.
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28
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Eizaguirre M, Alonso R, Vanotti S, Garcea O. Cognitive impairment in neuromyelitis optica spectrum disorders: What do we know? Mult Scler Relat Disord 2017; 18:225-229. [DOI: 10.1016/j.msard.2017.10.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 09/05/2017] [Accepted: 10/04/2017] [Indexed: 01/20/2023]
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29
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Hubbard JA, Binder DK. Unaltered Glutamate Transporter-1 Protein Levels in Aquaporin-4 Knockout Mice. ASN Neuro 2017; 9:1759091416687846. [PMID: 28078912 PMCID: PMC5315234 DOI: 10.1177/1759091416687846] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022] Open
Abstract
Maintenance of glutamate and water homeostasis in the brain is crucial to healthy brain activity. Astrocytic glutamate transporter-1 (GLT1) and aquaporin-4 (AQP4) are the main regulators of extracellular glutamate and osmolarity, respectively. Several studies have reported colocalization of GLT1 and AQP4, but the existence of a physical interaction between the two has not been well studied. Therefore, we used coimmunoprecipitation to determine whether a strong interaction exists between these two important molecules in mice on both a CD1 and C57BL/6 background. Furthermore, we used Western blot and immunohistochemistry to examine GLT1 levels in AQP4 knockout (AQP4−/−) mice. An AQP4-GLT1 precipitate was not detected, suggesting the lack of a strong physical interaction between AQP4 and GLT1. In addition, GLT1 protein levels remained unaltered in tissue from CD1 and C57BL/6 AQP4−/− mice. Finally, immunohistochemical analysis revealed that AQP4 and GLT1 do colocalize, but only in a region-specific manner. Taken together, these findings suggest that AQP4 and GLT1 do not have a strong physical interaction between them and are, instead, differentially regulated.
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Affiliation(s)
- Jacqueline A Hubbard
- 1 Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, University of California, Riverside, CA, USA
| | - Devin K Binder
- 1 Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, University of California, Riverside, CA, USA
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30
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Hubbard JA, Szu JI, Binder DK. The role of aquaporin-4 in synaptic plasticity, memory and disease. Brain Res Bull 2017; 136:118-129. [PMID: 28274814 DOI: 10.1016/j.brainresbull.2017.02.011] [Citation(s) in RCA: 86] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2016] [Revised: 02/27/2017] [Accepted: 02/28/2017] [Indexed: 12/25/2022]
Abstract
Since the discovery of aquaporins, it has become clear that the various mammalian aquaporins play critical physiological roles in water and ion balance in multiple tissues. Aquaporin-4 (AQP4), the principal aquaporin expressed in the central nervous system (CNS, brain and spinal cord), has been shown to mediate CNS water homeostasis. In this review, we summarize new and exciting studies indicating that AQP4 also plays critical and unanticipated roles in synaptic plasticity and memory formation. Next, we consider the role of AQP4 in Alzheimer's disease (AD), amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), multiple sclerosis (MS), neuromyelitis optica (NMO), epilepsy, traumatic brain injury (TBI), and stroke. Each of these conditions involves changes in AQP4 expression and/or distribution that may be functionally relevant to disease physiology. Insofar as AQP4 is exclusively expressed on astrocytes, these data provide new evidence of "astrocytopathy" in the etiology of diverse neurological diseases.
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Affiliation(s)
- Jacqueline A Hubbard
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, School of Medicine, University of California, Riverside, United States
| | - Jenny I Szu
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, School of Medicine, University of California, Riverside, United States
| | - Devin K Binder
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, School of Medicine, University of California, Riverside, United States.
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Yang C, Huang X, Huang X, Mai H, Li J, Jiang T, Wang X, Lü T. Aquaporin-4 and Alzheimer's Disease. J Alzheimers Dis 2017; 52:391-402. [PMID: 27031475 DOI: 10.3233/jad-150949] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Alzheimer's disease (AD) is the most common form of dementia. Although the pathogenesis of AD remains unclear, AD is thought to result from an imbalance in the production and clearance of amyloid-β protein (Aβ). Aquaporin-4 (AQP4) is the major aquaporin in the mammalian brain, is mostly expressed on astrocytic endfeet, and functions as a water transporter. However, the distribution and expression of AQP4 are altered in both AD clinical populations and animal models. Recent studies have revealed that AQP4 is important to the clearance of Aβ in brain via lymphatic clearance, transcytotic delivery, and glial degradation, as well as to the synaptic function. Thus, AQP4 likely plays an important role in the pathogenesis of AD. Further studies would provide new targets for prevention, ultimately leading to improved treatment options for AD.
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Yamashiro K, Morita M. Novel aspects of extracellular adenosine dynamics revealed by adenosine sensor cells. Neural Regen Res 2017; 12:881-885. [PMID: 28761414 PMCID: PMC5514856 DOI: 10.4103/1673-5374.208544] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Adenosine modulates diverse physiological and pathological processes in the brain, including neuronal activities, blood flow, and inflammation. However, the mechanisms underlying the dynamics of extracellular adenosine are not fully understood. We have recently developed a novel biosensor, called an adenosine sensor cell, and we have characterized the neuronal and astrocytic pathways for elevating extracellular adenosine. In this review, the physiological implications and therapeutic potential of the pathways revealed by the adenosine sensor cells are discussed. We propose that the multiple pathways regulating extracellular adenosine allow for the diverse functions of this neuromodulator, and their malfunctions cause various neurological and psychiatric disorders.
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Affiliation(s)
- Kunihiko Yamashiro
- Department of Biochemistry and Cellular Biology, National Institute of Neuroscience, National Center of Neurology and Psychiatry (NCNP), Tokyo, Japan.,Department of NCNP Brain Physiology and Pathology, Tokyo Medical and Dental University Graduate School of Medical and Dental Sciences, Tokyo, Japan.,Department of Biology, Kobe University Graduate School of Sciences, Kobe, Japan
| | - Mitsuhiro Morita
- Department of Biology, Kobe University Graduate School of Sciences, Kobe, Japan
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Filippidis AS, Carozza RB, Rekate HL. Aquaporins in Brain Edema and Neuropathological Conditions. Int J Mol Sci 2016; 18:ijms18010055. [PMID: 28036023 PMCID: PMC5297690 DOI: 10.3390/ijms18010055] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 12/20/2016] [Accepted: 12/20/2016] [Indexed: 01/22/2023] Open
Abstract
The aquaporin (AQP) family of water channels are a group of small, membrane-spanning proteins that are vital for the rapid transport of water across the plasma membrane. These proteins are widely expressed, from tissues such as the renal epithelium and erythrocytes to the various cells of the central nervous system. This review will elucidate the basic structure and distribution of aquaporins and discuss the role of aquaporins in various neuropathologies. AQP1 and AQP4, the two primary aquaporin molecules of the central nervous system, regulate brain water and CSF movement and contribute to cytotoxic and vasogenic edema, where they control the size of the intracellular and extracellular fluid volumes, respectively. AQP4 expression is vital to the cellular migration and angiogenesis at the heart of tumor growth; AQP4 is central to dysfunctions in glutamate metabolism, synaptogenesis, and memory consolidation; and AQP1 and AQP4 adaptations have been seen in obstructive and non-obstructive hydrocephalus and may be therapeutic targets.
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Affiliation(s)
- Aristotelis S Filippidis
- Division of Neurosurgery, Beth Israel Deaconess Medical School, Harvard Medical School, Boston, MA 02115, USA.
- Department of Neurosurgery, Boston Medical Center, Boston University, Boston, MA 02215, USA.
| | | | - Harold L Rekate
- Department of Neurosurgery, The Chiari Institute, Hofstra Northwell School of Medicine, Hempstead, NY 11549, USA.
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Aquaporin-4 and Cerebrovascular Diseases. Int J Mol Sci 2016; 17:ijms17081249. [PMID: 27529222 PMCID: PMC5000647 DOI: 10.3390/ijms17081249] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 07/20/2016] [Accepted: 07/26/2016] [Indexed: 12/16/2022] Open
Abstract
Cerebrovascular diseases are conditions caused by problems with brain vasculature, which have a high morbidity and mortality. Aquaporin-4 (AQP4) is the most abundant water channel in the brain and crucial for the formation and resolution of brain edema. Considering brain edema is an important pathophysiological change after stoke, AQP4 is destined to have close relation with cerebrovascular diseases. However, this relation is not limited to brain edema due to other biological effects elicited by AQP4. Till now, multiple studies have investigated roles of AQP4 in cerebrovascular diseases. This review focuses on expression of AQP4 and the effects of AQP4 on brain edema and neural cells injuries in cerebrovascular diseases including cerebral ischemia, intracerebral hemorrhage and subarachnoid hemorrhage. In the current review, we pay more attention to the studies of recent years directly from cerebrovascular diseases animal models or patients, especially those using AQP4 gene knockout mice. This review also elucidates the potential of AQP4as an excellent therapeutic target.
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Neuroimmunological Implications of AQP4 in Astrocytes. Int J Mol Sci 2016; 17:ijms17081306. [PMID: 27517922 PMCID: PMC5000703 DOI: 10.3390/ijms17081306] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Revised: 07/28/2016] [Accepted: 08/04/2016] [Indexed: 12/18/2022] Open
Abstract
The brain has high-order functions and is composed of several kinds of cells, such as neurons and glial cells. It is becoming clear that many kinds of neurodegenerative diseases are more-or-less influenced by astrocytes, which are a type of glial cell. Aquaporin-4 (AQP4), a membrane-bound protein that regulates water permeability is a member of the aquaporin family of water channel proteins that is expressed in the endfeet of astrocytes in the central nervous system (CNS). Recently, AQP4 has been shown to function, not only as a water channel protein, but also as an adhesion molecule that is involved in cell migration and neuroexcitation, synaptic plasticity, and learning/memory through mechanisms involved in long-term potentiation or long-term depression. The most extensively examined role of AQP4 is its ability to act as a neuroimmunological inducer. Previously, we showed that AQP4 plays an important role in neuroimmunological functions in injured mouse brain in concert with the proinflammatory inducer osteopontin (OPN). The aim of this review is to summarize the functional implication of AQP4, focusing especially on its neuroimmunological roles. This review is a good opportunity to compile recent knowledge and could contribute to the therapeutic treatment of autoimmune diseases through strategies targeting AQP4. Finally, the author would like to hypothesize on AQP4’s role in interaction between reactive astrocytes and reactive microglial cells, which might occur in neurodegenerative diseases. Furthermore, a therapeutic strategy for AQP4-related neurodegenerative diseases is proposed.
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Hubbard JA, Szu JI, Yonan JM, Binder DK. Regulation of astrocyte glutamate transporter-1 (GLT1) and aquaporin-4 (AQP4) expression in a model of epilepsy. Exp Neurol 2016; 283:85-96. [PMID: 27155358 DOI: 10.1016/j.expneurol.2016.05.003] [Citation(s) in RCA: 100] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 04/23/2016] [Accepted: 05/01/2016] [Indexed: 12/31/2022]
Abstract
Astrocytes regulate extracellular glutamate and water homeostasis through the astrocyte-specific membrane proteins glutamate transporter-1 (GLT1) and aquaporin-4 (AQP4), respectively. The role of astrocytes and the regulation of GLT1 and AQP4 in epilepsy are not fully understood. In this study, we investigated the expression of GLT1 and AQP4 in the intrahippocampal kainic acid (IHKA) model of temporal lobe epilepsy (TLE). We used real-time polymerase chain reaction (RT-PCR), Western blot, and immunohistochemical analysis at 1, 4, 7, and 30days after kainic acid-induced status epilepticus (SE) to determine hippocampal glial fibrillary acidic protein (GFAP, a marker for reactive astrocytes), GLT1, and AQP4 expression changes during the development of epilepsy (epileptogenesis). Following IHKA, all mice had SE and progressive increases in GFAP immunoreactivity and GFAP protein expression out to 30days post-SE. A significant initial increase in dorsal hippocampal GLT1 immunoreactivity and protein levels were observed 1day post SE and followed by a marked downregulation at 4 and 7days post SE with a return to near control levels by 30days post SE. AQP4 dorsal hippocampal protein expression was significantly downregulated at 1day post SE and was followed by a gradual return to baseline levels with a significant increase in ipsilateral protein levels by 30days post SE. Transient increases in GFAP and AQP4 mRNA were also observed. Our findings suggest that specific molecular changes in astrocyte glutamate transporters and water channels occur during epileptogenesis in this model, and suggest the novel therapeutic strategy of restoring glutamate and water homeostasis.
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Affiliation(s)
- Jacqueline A Hubbard
- Department of Biochemistry and Molecular Biology, University of California, Riverside, USA
| | - Jenny I Szu
- Neuroscience Graduate Program, University of California, Riverside, USA
| | - Jennifer M Yonan
- Neuroscience Graduate Program, University of California, Riverside, USA
| | - Devin K Binder
- Neuroscience Graduate Program, University of California, Riverside, USA; Center for Glial-Neuronal Interactions, University of California, Riverside, USA; Division of Biomedical Sciences, School of Medicine, University of California, Riverside.
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Szu JI, Binder DK. The Role of Astrocytic Aquaporin-4 in Synaptic Plasticity and Learning and Memory. Front Integr Neurosci 2016; 10:8. [PMID: 26941623 PMCID: PMC4764708 DOI: 10.3389/fnint.2016.00008] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 02/05/2016] [Indexed: 01/05/2023] Open
Abstract
Aquaporin-4 (AQP4) is the predominant water channel expressed by astrocytes in the central nervous system (CNS). AQP4 is widely expressed throughout the brain, especially at the blood-brain barrier where AQP4 is highly polarized to astrocytic foot processes in contact with blood vessels. The bidirectional water transport function of AQP4 suggests its role in cerebral water balance in the CNS. The regulation of AQP4 has been extensively investigated in various neuropathological conditions such as cerebral edema, epilepsy, and ischemia, however, the functional role of AQP4 in synaptic plasticity, learning, and memory is only beginning to be elucidated. In this review, we explore the current literature on AQP4 and its influence on long term potentiation (LTP) and long term depression (LTD) in the hippocampus as well as the potential relationship between AQP4 and in learning and memory. We begin by discussing recent in vitro and in vivo studies using AQP4-null and wild-type mice, in particular, the impairment of LTP and LTD observed in the hippocampus. Early evidence using AQP4-null mice have suggested that impaired LTP and LTD is brain-derived neurotrophic factor dependent. Others have indicated a possible link between defective LTP and the downregulation of glutamate transporter-1 which is rescued by chronic treatment of β-lactam antibiotic ceftriaxone. Furthermore, behavioral studies may shed some light into the functional role of AQP4 in learning and memory. AQP4-null mice performances utilizing Morris water maze, object placement tests, and contextual fear conditioning proposed a specific role of AQP4 in memory consolidation. All together, these studies highlight the potential influence AQP4 may have on long term synaptic plasticity and memory.
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Affiliation(s)
| | - Devin K. Binder
- Center for Glial-Neuronal Interactions, Division of Biomedical Sciences, School of Medicine, University of California, Riverside, RiversideCA, USA
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Xu Z, Xiao N, Chen Y, Huang H, Marshall C, Gao J, Cai Z, Wu T, Hu G, Xiao M. Deletion of aquaporin-4 in APP/PS1 mice exacerbates brain Aβ accumulation and memory deficits. Mol Neurodegener 2015; 10:58. [PMID: 26526066 PMCID: PMC4631089 DOI: 10.1186/s13024-015-0056-1] [Citation(s) in RCA: 295] [Impact Index Per Article: 32.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2015] [Accepted: 10/29/2015] [Indexed: 12/20/2022] Open
Abstract
Background Preventing or reducing amyloid-beta (Aβ) accumulation in the brain is an important therapeutic strategy for Alzheimer’s disease (AD). Recent studies showed that the water channel aquaporin-4 (AQP4) mediates soluble Aβ clearance from the brain parenchyma along the paravascular pathway. However the direct evidence for roles of AQP4 in the pathophysiology of AD remains absent. Results Here, we reported that the deletion of AQP4 exacerbated cognitive deficits of 12-moth old APP/PS1 mice, with increases in Aβ accumulation, cerebral amyloid angiopathy and loss of synaptic protein and brain-derived neurotrophic factor in the hippocampus and cortex. Furthermore, AQP4 deficiency increased atrophy of astrocytes with significant decreases in interleukin-1 beta and nonsignficant decreases in interleukin-6 and tumor necrosis factor-alpha in hippocampal and cerebral samples. Conclusions These results suggest that AQP4 attenuates Aβ pathogenesis despite its potentially inflammatory side-effects, thus serving as a promising target for treating AD. Electronic supplementary material The online version of this article (doi:10.1186/s13024-015-0056-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Zhiqiang Xu
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Na Xiao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Yali Chen
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Huang Huang
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Charles Marshall
- Department of Rehabilitation Sciences, University of Kentucky Center of Excellence in Rural Health, Hazard, KY, USA
| | - Junying Gao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Zhiyou Cai
- Department of Neurology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Ting Wu
- Department of Neurology, The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China
| | - Gang Hu
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China
| | - Ming Xiao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, 140 Hanzhong Road, Nanjing, Jiangsu, 210029, China.
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de Senna PN, Xavier LL, Bagatini PB, Saur L, Galland F, Zanotto C, Bernardi C, Nardin P, Gonçalves CA, Achaval M. Physical training improves non-spatial memory, locomotor skills and the blood brain barrier in diabetic rats. Brain Res 2015; 1618:75-82. [PMID: 26032744 DOI: 10.1016/j.brainres.2015.05.026] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2015] [Revised: 05/19/2015] [Accepted: 05/22/2015] [Indexed: 10/23/2022]
Abstract
Type 1 diabetes mellitus (T1DM) progressively affects cognitive domains, increases blood-brain barrier (BBB) permeability and promotes neurovascular impairment in specific brain areas. Physical exercise, on the other hand, has beneficial effects on brain functions, improving learning and memory. This study investigated the effects of treadmill training on cognitive and motor behavior, and on the expression of proteins related to BBB integrity, such as claudin-5 and aquaporin-4 (AQP4) in the hippocampus and striatum in diabetic rats. For this study, 60 Wistar rats were divided into four groups (n=15 per group): non-trained control (NTC), trained control (TC), non-trained diabetic (NTD), trained diabetic (TD). After diabetic induction of 30 days by streptozotocin injection, the exercise groups were submitted to 5 weeks of running training. After that, all groups were assessed in a novel object-recognition task (NOR) and the rotarod test. Additionally, claudin-5 and AQP4 levels were measured using biochemical assays. The results showed that exercise enhanced NOR task performance and rotarod ability in the TC and TD animals. Diabetes produced a decrease in claudin-5 expression in the hippocampus and striatum and reduced AQP4 in the hippocampus. Exercise preserved the claudin-5 content in the striatum of TD rats, but not in the hippocampus. The reduction of AQP4 levels produced by diabetes was not reversed by exercise. We conclude that exercise improves short-term memory retention, enhances motor performance in diabetic rats and affects important structural components of the striatal BBB. The results obtained could enhance the knowledge regarding the neurochemical benefits of exercise in diabetes.
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Affiliation(s)
- Priscylla Nunes de Senna
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Laboratório de Biologia Celular e Tecidual, Departamento de Ciências Morfofisiológicas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Léder Leal Xavier
- Laboratório de Biologia Celular e Tecidual, Departamento de Ciências Morfofisiológicas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Pamela Brambilla Bagatini
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Lisiani Saur
- Laboratório de Biologia Celular e Tecidual, Departamento de Ciências Morfofisiológicas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Fabiana Galland
- Departamento de Bioquímica, Instituto de Ciências Básica da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Caroline Zanotto
- Departamento de Bioquímica, Instituto de Ciências Básica da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Caren Bernardi
- Universidade Federal de Ciências da Saúde de Porto Alegre, Porto Alegre, Brazil
| | - Patrícia Nardin
- Departamento de Bioquímica, Instituto de Ciências Básica da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Carlos Alberto Gonçalves
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Departamento de Bioquímica, Instituto de Ciências Básica da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Matilde Achaval
- Programa de Pós-Graduação em Neurociências, Instituto de Ciências Básicas da Saúde, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
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Jukkola P, Gu C. Regulation of neurovascular coupling in autoimmunity to water and ion channels. Autoimmun Rev 2015; 14:258-67. [PMID: 25462580 PMCID: PMC4303502 DOI: 10.1016/j.autrev.2014.11.010] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Accepted: 11/15/2014] [Indexed: 12/27/2022]
Abstract
Much progress has been made in understanding autoimmune channelopathies, but the underlying pathogenic mechanisms are not always clear due to broad expression of some channel proteins. Recent studies show that autoimmune conditions that interfere with neurovascular coupling in the central nervous system (CNS) can lead to neurodegeneration. Cerebral blood flow that meets neuronal activity and metabolic demand is tightly regulated by local neural activity. This process of reciprocal regulation involves coordinated actions of a number of cell types, including neurons, glia, and vascular cells. In particular, astrocytic endfeet cover more than 90% of brain capillaries to assist blood-brain barrier (BBB) function, and wrap around synapses and nodes of Ranvier to communicate with neuronal activity. In this review, we highlight four types of channel proteins that are expressed in astrocytes, regarding their structures, biophysical properties, expression and distribution patterns, and related diseases including autoimmune disorders. Water channel aquaporin 4 (AQP4) and inwardly rectifying potassium (Kir4.1) channels are concentrated in astrocytic endfeet, whereas some voltage-gated Ca(2+) and two-pore domain K(+) channels are expressed throughout the cell body of reactive astrocytes. More channel proteins are found in astrocytes under normal and abnormal conditions. This research field will contribute to a better understanding of pathogenic mechanisms underlying autoimmune disorders.
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Affiliation(s)
- Peter Jukkola
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA
| | - Chen Gu
- Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH 43210, USA; Department of Neuroscience, The Ohio State University, Columbus, OH 43210, USA.
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Xiao M, Hu G. Involvement of aquaporin 4 in astrocyte function and neuropsychiatric disorders. CNS Neurosci Ther 2014; 20:385-90. [PMID: 24712483 PMCID: PMC6493026 DOI: 10.1111/cns.12267] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2014] [Revised: 03/14/2014] [Accepted: 03/14/2014] [Indexed: 12/21/2022] Open
Abstract
Aquaporin 4 (AQP4) is the main water channel in the central nervous system (CNS) and specifically localized to astrocyte processes. Recent studies indicate that AQP4 regulates various biological functions of astrocytes, including maintaining CNS water balance, spatial buffering of extracellular potassium, calcium signal transduction, regulation of neurotransmission, synaptic plasticity, and adult neurogenesis, while under neuropathological conditions, AQP4 has a role in astrogliosis and proinflammatory cytokine secretion. In addition, accumulating evidence suggests that, besides cerebral edema, neuromyelitis optica and epilepsy, AQP4 participates in the onset and progression of Alzheimer disease, Parkinson disease, depression, and drug addiction. This review summarizes recent findings and highlights the involvement of AQP4 in astrocyte function and neuropsychiatric disorders.
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Affiliation(s)
- Ming Xiao
- Jiangsu Key Laboratory of Neurodegeneration, Nanjing Medical University, Nanjing, China
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Abstract
Aquaporin-4 (AQP4) is one of the most abundant molecules in the brain and is particularly prevalent in astrocytic membranes at the blood-brain and brain-liquor interfaces. While AQP4 has been implicated in a number of pathophysiological processes, its role in brain physiology has remained elusive. Only recently has evidence accumulated to suggest that AQP4 is involved in such diverse functions as regulation of extracellular space volume, potassium buffering, cerebrospinal fluid circulation, interstitial fluid resorption, waste clearance, neuroinflammation, osmosensation, cell migration, and Ca(2+) signaling. AQP4 is also required for normal function of the retina, inner ear, and olfactory system. A review will be provided of the physiological roles of AQP4 in brain and of the growing list of data that emphasize the polarized nature of astrocytes.
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Zhang J, Li Y, Chen ZG, Dang H, Ding JH, Fan Y, Hu G. Glia protein aquaporin-4 regulates aversive motivation of spatial memory in Morris water maze. CNS Neurosci Ther 2013; 19:937-44. [PMID: 24165567 DOI: 10.1111/cns.12191] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2013] [Revised: 09/22/2013] [Accepted: 09/23/2013] [Indexed: 01/05/2023] Open
Abstract
AIMS Although extensive investigation has revealed that an astrocyte-specific protein aquaporin-4 (AQP4) participates in regulating synaptic plasticity and memory, a functional relationship between AQP4 and learning processing has not been clearly established. This study was designed to test our hypothesis that AQP4 modulates the aversive motivation in Morris water maze (MWM). METHODS AND RESULTS Using hidden platform training, we observed that AQP4 KO mice significantly decreased their swimming velocity compared with wild-type (WT) mice. To test for a relationship between velocities and escape motivation, we removed the platform and subjected a new group of mice similar to the session of hidden platform training. We found that KO mice exhibited a gradual reduction in swimming velocity, while WT mice did not alter their velocity. In the subsequent probe trial, KO mice after no platform training significantly decreased their mean velocity compared with those KO mice after hide platform training. However, all of KO mice were not impaired in their ability to locate a visible, cued escape platform. CONCLUSIONS Our findings, along with a previous report that AQP4 regulates memory consolidation, implicate a novel role for this glial protein in modulating the aversive motivation in spatial learning paradigm.
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Affiliation(s)
- Ji Zhang
- Division of Clinical Pharmacy, Department of Pharmacy, the First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu, China; Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, Nanjing, Jiangsu, China
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Abstract
The aquaporins (AQPs) are plasma membrane water-transporting proteins. AQP4 is the principal member of this protein family in the CNS, where it is expressed in astrocytes and is involved in water movement, cell migration and neuroexcitation. AQP1 is expressed in the choroid plexus, where it facilitates cerebrospinal fluid secretion, and in dorsal root ganglion neurons, where it tunes pain perception. The AQPs are potential drug targets for several neurological conditions. Astrocytoma cells strongly express AQP4, which may facilitate their infiltration into the brain, and the neuroinflammatory disease neuromyelitis optica is caused by AQP4-specific autoantibodies that produce complement-mediated astrocytic damage.
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Affiliation(s)
- Marios C Papadopoulos
- Academic Neurosurgery Unit, St. George's, University of London, Tooting, London, SW17 0RE, UK. mpapadop@sgul. ac.uk
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