1
|
Ruan J, Kang M, Nirwane A, Yao Y. A dispensable role of mural cell-derived laminin- α5 in intracerebral hemorrhage. J Cereb Blood Flow Metab 2024:271678X241264083. [PMID: 39053486 DOI: 10.1177/0271678x241264083] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 07/27/2024]
Abstract
Although most laminin isoforms are neuroprotective in stroke, mural cell-derived laminin-α5 plays a detrimental role in an ischemia-reperfusion model. To determine whether this deleterious effect is an intrinsic feature of mural cell-derived laminin-α5 or unique to ischemic stroke, we performed loss-of-function studies using middle-aged mice with laminin-α5 deficiency in mural cells (α5-PKO) in an intracerebral hemorrhage (ICH) model. Control and α5-PKO mice exhibited comparable changes in all parameters examined, including hematoma size, neuronal death, neurological function, blood-brain barrier integrity, and reactive gliosis. These findings highlight a minimal role of mural cell-derived laminin-α5 in ICH. Together with the detrimental role of mural cell-derived laminin-α5 in ischemic stroke, these negative results in ICH model suggest that mural cell-derived laminin-α5 may exert distinct functions in different diseases.
Collapse
Affiliation(s)
- Jingsong Ruan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Minkyung Kang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Abhijit Nirwane
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| |
Collapse
|
2
|
Kang M, Yao Y. Oligodendrocyte-derived laminin-γ1 regulates the blood-brain barrier and CNS myelination in mice. Cell Rep 2024; 43:114123. [PMID: 38635399 PMCID: PMC11154164 DOI: 10.1016/j.celrep.2024.114123] [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: 08/05/2023] [Revised: 02/15/2024] [Accepted: 04/02/2024] [Indexed: 04/20/2024] Open
Abstract
Although oligodendrocytes (OLs) synthesize laminin-γ1, the most widely used γ subunit, its functional significance in the CNS remains unknown. To answer this important question, we generated a conditional knockout mouse line with laminin-γ1 deficiency in OL lineage cells (γ1-OKO). γ1-OKO mice exhibit weakness/paralysis and die by post-natal day 33. Additionally, they develop blood-brain barrier (BBB) disruption in the cortex and striatum. Subsequent studies reveal decreased major facilitator superfamily domain containing 2a expression and increased endothelial caveolae vesicles, but unaltered tight junction protein expression and tight junction ultrastructure, indicating a transcellular, rather than a paracellular, mechanism of BBB breakdown. Furthermore, significantly reduced OL lineage cells, OL precursor cells (OPCs), proliferating OPCs, and mature OLs are observed in γ1-OKO brains in a region-specific manner. Consistent with this finding, various defects in myelination are detected in γ1-OKO brains at biochemical and ultrastructural levels. Overall, these results highlight important roles of OL-derived laminin-γ1 in BBB maintenance and OL biology (proliferation, differentiation, and myelination).
Collapse
Affiliation(s)
- Minkyung Kang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL 33612, USA.
| |
Collapse
|
3
|
Kang M, Nirwane A, Ruan J, Adithan A, Gray M, Xu L, Yao Y. A dispensable role of oligodendrocyte-derived laminin-α5 in brain homeostasis and intracerebral hemorrhage. J Cereb Blood Flow Metab 2024; 44:611-623. [PMID: 38241459 PMCID: PMC10981398 DOI: 10.1177/0271678x241228058] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 12/22/2023] [Accepted: 01/05/2024] [Indexed: 01/21/2024]
Abstract
Laminin, a major component of the basal lamina in the CNS, is also expressed in oligodendrocytes (OLs). However, the function of OL-derived laminin remains largely unknown. Here, we performed loss-of-function studies using two OL-specific laminin-α5 conditional knockout mouse lines. Both mutants were grossly normal and displayed intact blood-brain barrier (BBB) integrity. In a mouse model of intracerebral hemorrhage (ICH), control mice and both mutants exhibited comparable hematoma size and neurological dysfunction. In addition, similar levels of hemoglobin and IgG leakage were detected in the mutant brains compared to the controls, indicating comparable BBB damage. Consistent with this finding, subsequent studies revealed no differences in tight junction protein (TJP) and caveolin-1 expression among control and knockout mice, suggesting that neither paracellular nor transcellular mechanism was affected in the mutants. Furthermore, compared to the controls, both mutant lines showed comparable oligodendrocyte number, oligodendrocyte proliferation rate, MBP/MAG levels, and SMI-32 expression, highlighting a minimal role of OL-derived laminin-α5 in OL biology. Together, these findings highlight a dispensable role of OL-derived laminin-α5 in both brain homeostasis and ICH pathogenesis.
Collapse
Affiliation(s)
- Minkyung Kang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Abhijit Nirwane
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Jingsong Ruan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Aravinthan Adithan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Marsilla Gray
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Lingling Xu
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
- Current Address: Department of Pediatrics, Emory University School of Medicine, Atlanta, GA, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| |
Collapse
|
4
|
Nirwane A, Kang M, Adithan A, Maharaj V, Nguyen F, Santaella Aguilar E, Nasrollahi A, Yao Y. Endothelial and mural laminin-α5 contributes to neurovascular integrity maintenance. Fluids Barriers CNS 2024; 21:18. [PMID: 38383451 PMCID: PMC10882802 DOI: 10.1186/s12987-024-00521-z] [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: 12/16/2023] [Accepted: 02/08/2024] [Indexed: 02/23/2024] Open
Abstract
BACKGROUND Laminin-α5, a major component of the basal lamina, is predominantly synthesized by endothelial and mural cells (pericytes and vascular smooth muscle cells) in the CNS. Loss of laminin-α5 in either population fails to induce any abnormalities due to functional redundancy. Thus, the functional significance of laminin-α5 in neurovascular integrity remains unknown. Here, we hypothesize that ablation of laminin-α5 in both endothelial and mural cells increases neurovascular permeability. METHODS The compound knockout mice were generated by crossing laminin-α5 floxed mice with Tie2-Cre and PDGFRβ-Cre, which target endothelial cells and mural cells, respectively. Neurovascular permeability in these mutants was determined with both exogenous and endogenous tracers. Endothelial paracellular and transcellular permeability was assessed by examining the expression of tight junction proteins and transcytosis-associated proteins. In addition, transmission electron microscopy (TEM) was used to visualize tight junction ultrastructure and endothelial caveolae vesicles. Defects in pericytes and astrocytes were investigated by examining pericyte coverage/contact and astrocyte polarity. RESULTS Elevated neurovascular permeability was observed in the mutants. Subsequent studies found increased Caveolin-1 and decreased major facilitator superfamily domain-containing protein 2a (MFSD2A) expression, but unaltered Claudin-5 or zonula occludens-1 (ZO-1) expression. Consistent with these results, mutant mice exhibited increased endothelial caveolae vesicle number with intact tight junction structure under TEM. Additionally, pericyte coverage and contact were also decreased in the mutant mice, while astrocyte polarity was unaffected. CONCLUSIONS These results strongly indicate that endothelial and mural cell-derived laminin-α5 actively maintains neurovascular integrity via the transcellular rather than paracellular mechanism.
Collapse
Affiliation(s)
- Abhijit Nirwane
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Minkyung Kang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Aravinthan Adithan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Vrishni Maharaj
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Felicia Nguyen
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Elliot Santaella Aguilar
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Ava Nasrollahi
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, 33612, Tampa, FL, USA.
| |
Collapse
|
5
|
Hu S, Yang B, Shu S, He X, Sang H, Fan X, Zhang H. Targeting Pericytes for Functional Recovery in Ischemic Stroke. Neuromolecular Med 2023; 25:457-470. [PMID: 37166748 DOI: 10.1007/s12017-023-08748-z] [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: 02/24/2023] [Accepted: 05/03/2023] [Indexed: 05/12/2023]
Abstract
Pericytes surrounding endothelial cells in the capillaries are emerging as an attractive cell resource, which can show a large variety of functions in ischemic stroke, including preservation of the blood-brain barrier, regulation of immune function, and support for cerebral vasculature. These functions have been fully elucidated in previous studies. However, in recent years, increasing evidence has shown that pericytes play an important role in neurological recovery after ischemic stroke due to their regenerative function which can be summarized in two aspects according to current discoveries, one is that pericytes are thought to be multipotential themselves, and the other is that pericytes can promote the differentiation of oligodendrocyte progenitor cells (OPCs). Considering the neuroprotective treatment for stroke has not been much progressed in recent years, new therapies targeting pericytes may be a future direction. Here, we will review the beneficial effects of pericytes in ischemic stroke from two directions: the barrier and vascular functions and the regenerative functions of pericytes.
Collapse
Affiliation(s)
- Shuqi Hu
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Bingjie Yang
- Department of Neurology, The Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China
| | - Song Shu
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Xudong He
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Hongfei Sang
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Xuemei Fan
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China
| | - Hao Zhang
- Department of Neurology, Affiliated Hangzhou First People's Hospital, Zhejiang University School of Medicine, Hangzhou, 310006, Zhejiang, China.
- Department of Neurology, The Fourth Clinical School of Medicine, Zhejiang Chinese Medical University, Hangzhou, 310053, Zhejiang, China.
| |
Collapse
|
6
|
Halder SK, Sapkota A, Milner R. The importance of laminin at the blood-brain barrier. Neural Regen Res 2023; 18:2557-2563. [PMID: 37449589 DOI: 10.4103/1673-5374.373677] [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] [Indexed: 07/18/2023] Open
Abstract
The blood-brain barrier is a unique property of central nervous system blood vessels that protects sensitive central nervous system cells from potentially harmful blood components. The mechanistic basis of this barrier is found at multiple levels, including the adherens and tight junction proteins that tightly bind adjacent endothelial cells and the influence of neighboring pericytes, microglia, and astrocyte endfeet. In addition, extracellular matrix components of the vascular basement membrane play a critical role in establishing and maintaining blood-brain barrier integrity, not only by providing an adhesive substrate for blood-brain barrier cells to adhere to, but also by providing guidance cues that strongly influence vascular cell behavior. The extracellular matrix protein laminin is one of the most abundant components of the basement membrane, and several lines of evidence suggest that it plays a key role in directing blood-brain barrier behavior. In this review, we describe the basic structure of laminin and its receptors, the expression patterns of these molecules in central nervous system blood vessels and how they are altered in disease states, and most importantly, how genetic deletion of different laminin isoforms or their receptors reveals the contribution of these molecules to blood-brain barrier function and integrity. Finally, we discuss some of the important unanswered questions in the field and provide a "to-do" list of some of the critical outstanding experiments.
Collapse
Affiliation(s)
- Sebok K Halder
- San Diego Biomedical Research Institute, San Diego, CA, USA
| | - Arjun Sapkota
- San Diego Biomedical Research Institute, San Diego, CA, USA
| | - Richard Milner
- San Diego Biomedical Research Institute, San Diego, CA, USA
| |
Collapse
|
7
|
Li H, Ghorbani S, Ling CC, Yong VW, Xue M. The extracellular matrix as modifier of neuroinflammation and recovery in ischemic stroke and intracerebral hemorrhage. Neurobiol Dis 2023; 186:106282. [PMID: 37683956 DOI: 10.1016/j.nbd.2023.106282] [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: 05/28/2023] [Revised: 09/01/2023] [Accepted: 09/05/2023] [Indexed: 09/10/2023] Open
Abstract
Stroke is the second leading cause of death worldwide and has two major subtypes: ischemic stroke and hemorrhagic stroke. Neuroinflammation is a pathological hallmark of ischemic stroke and intracerebral hemorrhage (ICH), contributing to the extent of brain injury but also in its repair. Neuroinflammation is intricately linked to the extracellular matrix (ECM), which is profoundly altered after brain injury and in aging. In the early stages after ischemic stroke and ICH, immune cells are involved in the deposition and remodeling of the ECM thereby affecting processes such as blood-brain barrier and cellular integrity. ECM components regulate leukocyte infiltration into the central nervous system, activate a variety of immune cells, and induce the elevation of matrix metalloproteinases (MMPs) after stroke. In turn, excessive MMPs may degrade ECM into components that are pro-inflammatory and injurious. Conversely, in the later stages after stroke, several ECM molecules may contribute to tissue recovery. For example, thrombospondin-1 and biglycan may promote activity of regulatory T cells, inhibit the synthesis of proinflammatory cytokines, and aid regenerative processes. We highlight these roles of the ECM in ischemic stroke and ICH and discuss their potential cellular and molecular mechanisms. Finally, we discuss therapeutics that could be considered to normalize the ECM in stroke. Our goal is to spur research on the ECM in order to improve the prognosis of ischemic stroke and ICH.
Collapse
Affiliation(s)
- Hongmin Li
- Department of Cerebrovascular Diseases, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China; Academy of Medical Science, Zhengzhou University, Zhengzhou, Henan, China; Hotchkiss Brain Institute and Department of Clinical Neurosciences, University of Calgary, Alberta, Canada
| | - Samira Ghorbani
- Hotchkiss Brain Institute and Department of Clinical Neurosciences, University of Calgary, Alberta, Canada
| | - Chang-Chun Ling
- Department of Chemistry, University of Calgary, Alberta, Canada
| | - V Wee Yong
- Hotchkiss Brain Institute and Department of Clinical Neurosciences, University of Calgary, Alberta, Canada.
| | - Mengzhou Xue
- Department of Cerebrovascular Diseases, The Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.
| |
Collapse
|
8
|
Nakamura K, Ago T. Pericyte-Mediated Molecular Mechanisms Underlying Tissue Repair and Functional Recovery after Ischemic Stroke. J Atheroscler Thromb 2023; 30:1085-1094. [PMID: 37394570 PMCID: PMC10499454 DOI: 10.5551/jat.rv22007] [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: 05/19/2023] [Accepted: 05/19/2023] [Indexed: 07/04/2023] Open
Abstract
There are still many patients suffering from ischemic stroke and related disabilities worldwide. To develop a treatment that promotes functional recovery after acute ischemic stroke, we need to elucidate endogenous tissue repair mechanisms. The concept of a neurovascular unit (NVU) indicates the importance of a complex orchestration of cell-cell interactions and their microenvironment in the physiology and pathophysiology of various central nervous system diseases, particularly ischemic stroke. In this concept, microvascular pericytes play a crucial role in regulating the blood-brain barrier integrity, cerebral blood flow (CBF), and vascular stability. Recent evidence suggests that pericytes are also involved in the tissue repair leading to functional recovery following acute ischemic stroke through the interaction with other cell types constituting the NVU; pericytes may organize CBF recovery, macrophage-mediated clearance of myelin debris, intrainfarct fibrosis, and periinfarct astrogliosis and remyelination. In this review, we will discuss the physiological and pathophysiological functions of pericytes, their involvement in the molecular mechanisms underlying tissue repair and functional recovery after ischemic stroke, and a therapeutic strategy to promote endogenous regeneration.
Collapse
Affiliation(s)
- Kuniyuki Nakamura
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| | - Tetsuro Ago
- Department of Medicine and Clinical Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
| |
Collapse
|
9
|
Ruan J, McKee KK, Yurchenco PD, Yao Y. Exogenous laminin exhibits a unique vascular pattern in the brain via binding to dystroglycan and integrins. Fluids Barriers CNS 2022; 19:97. [PMID: 36463265 PMCID: PMC9719645 DOI: 10.1186/s12987-022-00396-y] [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: 08/16/2022] [Accepted: 11/28/2022] [Indexed: 12/07/2022] Open
Abstract
BACKGROUND Unlike other proteins that exhibit a diffusion pattern after intracerebral injection, laminin displays a vascular pattern. It remains unclear if this unique vascular pattern is caused by laminin-receptor interaction or laminin self-assembly. METHODS We compared the distribution of various wild-type laminin isoforms in the brain after intracerebral injection. To determine what causes the unique vascular pattern of laminin in the brain, laminin mutants with impaired receptor-binding and/or self-assembly activities and function-blocking antibodies to laminin receptors were used. In addition, the dynamics of laminin distribution and elimination were examined at multiple time points after intracerebral injection. RESULTS We found that β2-containing laminins had higher affinity for the vessels compared to β1-containing laminins. In addition, laminin mutants lacking receptor-binding domains but not that lacking self-assembly capability showed substantially reduced vascular pattern. Consistent with this finding, dystroglycan (DAG1) function-blocking antibody significantly reduced the vascular pattern of wild-type laminin-111. Although failed to affect the vascular pattern when used alone, integrin-β1 function-blocking antibody further decreased the vascular pattern when combined with DAG1 antibody. EDTA, which impaired laminini-DAG1 interaction by chelating Ca2+, also attenuated the vascular pattern. Immunohistochemistry revealed that laminins were predominantly located in the perivascular space in capillaries and venules/veins but not arterioles/arteries. The time-course study showed that laminin mutants with impaired receptor-engaging activity were more efficiently eliminated from the brain compared to their wild-type counterparts. Concordantly, significantly higher levels of mutant laminins were detected in the cerebral-spinal fluid (CSF). CONCLUSIONS These findings suggest that intracerebrally injected laminins are enriched in the perivascular space in a receptor (DAG1/integrin)-dependent rather than self-assembly-dependent manner and eliminated from the brain mainly via the perivascular clearance system.
Collapse
Affiliation(s)
- Jingsong Ruan
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, Tampa, FL, 33612, USA
| | - Karen K McKee
- Department of Pathology and Laboratory Medicine, Rutgers University-Robert W. Johnson Medical School, Piscataway, NJ, USA
| | - Peter D Yurchenco
- Department of Pathology and Laboratory Medicine, Rutgers University-Robert W. Johnson Medical School, Piscataway, NJ, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, 12901 Bruce B. Downs Blvd., MDC 8, Tampa, FL, 33612, USA.
| |
Collapse
|
10
|
Xu L, Nirwane A, Xu T, Kang M, Devasani K, Yao Y. Fibroblasts repair blood-brain barrier damage and hemorrhagic brain injury via TIMP2. Cell Rep 2022; 41:111709. [DOI: 10.1016/j.celrep.2022.111709] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Revised: 09/11/2022] [Accepted: 11/01/2022] [Indexed: 11/23/2022] Open
|
11
|
Nirwane A, Yao Y. Cell-specific expression and function of laminin at the neurovascular unit. J Cereb Blood Flow Metab 2022; 42:1979-1999. [PMID: 35796497 PMCID: PMC9580165 DOI: 10.1177/0271678x221113027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/26/2022] [Revised: 06/08/2022] [Accepted: 06/19/2022] [Indexed: 11/17/2022]
Abstract
Laminin, a major component of the basal lamina (BL), is a heterotrimeric protein with many isoforms. In the CNS, laminin is expressed by almost all cell types, yet different cells synthesize distinct laminin isoforms. By binding to its receptors, laminin exerts a wide variety of important functions. However, due to the reciprocal and cell-specific expression of laminin in different cells at the neurovascular unit, its functions in blood-brain barrier (BBB) maintenance and BBB repair after injury are not fully understood. In this review, we focus on the expression and functions of laminin and its receptors in the neurovascular unit under both physiological and pathological conditions. We first briefly introduce the structures of laminin and its receptors. Next, the expression and functions of laminin and its receptors in the CNS are summarized in a cell-specific manner. Finally, we identify the knowledge gap in the field and discuss key questions that need to be answered in the future. Our goal is to provide a comprehensive overview on cell-specific expression of laminin and its receptors in the CNS and their functions on BBB integrity.
Collapse
Affiliation(s)
- Abhijit Nirwane
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, FL, USA
| |
Collapse
|
12
|
Halder SK, Sapkota A, Milner R. The impact of genetic manipulation of laminin and integrins at the blood-brain barrier. Fluids Barriers CNS 2022; 19:50. [PMID: 35690759 PMCID: PMC9188059 DOI: 10.1186/s12987-022-00346-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 05/18/2022] [Indexed: 12/26/2022] Open
Abstract
Blood vessels in the central nervous system (CNS) are unique in having high electrical resistance and low permeability, which creates a selective barrier protecting sensitive neural cells within the CNS from potentially harmful components in the blood. The molecular basis of this blood–brain barrier (BBB) is found at the level of endothelial adherens and tight junction protein complexes, extracellular matrix (ECM) components of the vascular basement membrane (BM), and the influence of adjacent pericytes and astrocyte endfeet. Current evidence supports the concept that instructive cues from the BBB ECM are not only important for the development and maturation of CNS blood vessels, but they are also essential for the maintenance of vascular stability and BBB integrity. In this review, we examine the contributions of one of the most abundant ECM proteins, laminin to BBB integrity, and summarize how genetic deletions of different laminin isoforms or their integrin receptors impact BBB development, maturation, and stability.
Collapse
Affiliation(s)
- Sebok K Halder
- San Diego Biomedical Research Institute, 3525 John Hopkins Court, Suite 200, San Diego, CA, 92121, USA
| | - Arjun Sapkota
- San Diego Biomedical Research Institute, 3525 John Hopkins Court, Suite 200, San Diego, CA, 92121, USA
| | - Richard Milner
- San Diego Biomedical Research Institute, 3525 John Hopkins Court, Suite 200, San Diego, CA, 92121, USA.
| |
Collapse
|
13
|
Wang Y, Kisler K, Nikolakopoulou AM, Fernandez JA, Griffin JH, Zlokovic BV. 3K3A-Activated Protein C Protects the Blood-Brain Barrier and Neurons From Accelerated Ischemic Injury Caused by Pericyte Deficiency in Mice. Front Neurosci 2022; 16:841916. [PMID: 35431776 PMCID: PMC9005806 DOI: 10.3389/fnins.2022.841916] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2021] [Accepted: 02/16/2022] [Indexed: 11/16/2022] Open
Abstract
Pericytes, mural cells of brain capillaries, maintain the blood-brain barrier (BBB), regulate cerebral blood flow (CBF), and protect neurons against ischemic damage. To further investigate the role of pericytes in ischemia, we induced stroke by 45-min transient middle cerebral artery occlusion (tMCAo) in 6-month-old pericyte-deficient Pdgfrb + /- mice and control Pdgfrb+/+ littermates. Compared to controls, Pdgfrb + /- mice showed a 26% greater loss of CBF during early reperfusion, and 40-50% increase in the infarct and edema volumes and motor neurological score 24 h after tMCAo. These changes were accompanied by 50% increase in both immunoglobulin G and fibrinogen pericapillary deposits in the ischemic cortex 8 h after tMCAo indicating an accelerated BBB breakdown, and 35 and 55% greater losses of pericyte coverage and number of degenerating neurons 24 h after tMCAo, respectively. Treatment of Pdgfrb + /- mice with 3K3A-activated protein C (APC), a cell-signaling analog of plasma protease APC, administered intravenously 10 min and 4 h after tMCAo normalized CBF during the early reperfusion phase and reduced infarct and edema volume and motor neurological score by 55-60%, with similar reductions in BBB breakdown and number of degenerating neurons. Our data suggest that pericyte deficiency results in greater brain injury, BBB breakdown, and neuronal degeneration in stroked mice and that 3K3A-APC protects the brain from accelerated injury caused by pericyte deficiency. These findings may have implications for treatment of ischemic brain injury in neurological conditions associated with pericyte loss such as those seen during normal aging and in neurodegenerative disorders such as Alzheimer's disease.
Collapse
Affiliation(s)
- Yaoming Wang
- Department of Physiology and Neuroscience, Keck School of Medicine, Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA, United States
| | - Kassandra Kisler
- Department of Physiology and Neuroscience, Keck School of Medicine, Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA, United States
| | - Angeliki Maria Nikolakopoulou
- Department of Physiology and Neuroscience, Keck School of Medicine, Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA, United States
| | - Jose A. Fernandez
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
| | - John H. Griffin
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, United States
- Division of Hematology/Oncology, Department of Medicine, University of California, San Diego, San Diego, CA, United States
| | - Berislav V. Zlokovic
- Department of Physiology and Neuroscience, Keck School of Medicine, Zilkha Neurogenetic Institute, University of Southern California, Los Angeles, CA, United States
| |
Collapse
|
14
|
Zheng X, Yang J, Zhu Z, Fang Y, Tian Y, Xie M, Wang W, Liu Y. The Two-Pore Domain Potassium Channel TREK-1 Promotes Blood-Brain Barrier Breakdown and Exacerbates Neuronal Death After Focal Cerebral Ischemia in Mice. Mol Neurobiol 2022; 59:2305-2327. [PMID: 35067892 DOI: 10.1007/s12035-021-02702-5] [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: 09/16/2021] [Accepted: 12/14/2021] [Indexed: 11/24/2022]
Abstract
Earlier studies have shown the neuroprotective role of TWIK-related K+ channel 1 (TREK-1) in global cerebral and spinal cord ischemia, while its function in focal cerebral ischemia has long been debated. This study used TREK-1-deficient mice to directly investigate the role of TREK-1 after focal cerebral ischemia. First, immunofluorescence assays in the mouse cerebral cortex indicated that TREK-1 expression was mostly abundant in astrocytes, neurons, and oligodendrocyte precursor cells but was low in myelinating oligodendrocytes, microglia, or endothelial cells. TREK-1 deficiency did not affect brain weight and morphology or the number of neurons, astrocytes, or microglia but did increase glial fibrillary acidic protein (GFAP) expression in astrocytes of the cerebral cortex. The anatomy of the major cerebral vasculature, number and structure of brain micro blood vessels, and blood-brain barrier integrity were unaltered. Next, mice underwent 60 min of focal cerebral ischemia and 72 h of reperfusion induced by the intraluminal suture method. TREK-1-deficient mice showed less neuronal death, smaller infarction size, milder blood-brain barrier (BBB) breakdown, reduced immune cell invasion, and better neurological function. Finally, the specific pharmacological inhibition of TREK-1 also decreased infarction size and improved neurological function. These results demonstrated that TREK-1 might play a detrimental rather than beneficial role in focal cerebral ischemia, and inhibition of TREK-1 would be a strategy to treat ischemic stroke in the clinic.
Collapse
Affiliation(s)
- Xiaolong Zheng
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Jun Yang
- Department of Urology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Zhou Zhu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yongkang Fang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yeye Tian
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Minjie Xie
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Wei Wang
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.,Key Laboratory of Neurological Diseases of Chinese Ministry of Education, School of Basic Medicine, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China
| | - Yang Liu
- Department of Neurology, Tongji Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, 430030, China.
| |
Collapse
|
15
|
Kang M, Yao Y. Laminin regulates oligodendrocyte development and myelination. Glia 2021; 70:414-429. [PMID: 34773273 DOI: 10.1002/glia.24117] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2021] [Revised: 10/26/2021] [Accepted: 10/29/2021] [Indexed: 11/08/2022]
Abstract
Oligodendrocytes are the cells that myelinate axons and provide trophic support to neurons in the CNS. Their dysfunction has been associated with a group of disorders known as demyelinating diseases, such as multiple sclerosis. Oligodendrocytes are derived from oligodendrocyte precursor cells, which differentiate into premyelinating oligodendrocytes and eventually mature oligodendrocytes. The development and function of oligodendrocytes are tightly regulated by a variety of molecules, including laminin, a major protein of the extracellular matrix. Accumulating evidence suggests that laminin actively regulates every aspect of oligodendrocyte biology, including survival, migration, proliferation, differentiation, and myelination. How can laminin exert such diverse functions in oligodendrocytes? It is speculated that the distinct laminin isoforms, laminin receptors, and/or key signaling molecules expressed in oligodendrocytes at different developmental stages are the reasons. Understanding molecular targets and signaling pathways unique to each aspect of oligodendrocyte biology will enable more accurate manipulation of oligodendrocyte development and function, which may have implications in the therapies of demyelinating diseases. Here in this review, we first introduce oligodendrocyte biology, followed by the expression of laminin and laminin receptors in oligodendrocytes and other CNS cells. Next, the functions of laminin in oligodendrocyte biology, including survival, migration, proliferation, differentiation, and myelination, are discussed in detail. Last, key questions and challenges in the field are discussed. By providing a comprehensive review on laminin's roles in OL lineage cells, we hope to stimulate novel hypotheses and encourage new research in the field.
Collapse
Affiliation(s)
- Minkyung Kang
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| | - Yao Yao
- Department of Molecular Pharmacology and Physiology, Morsani College of Medicine, University of South Florida, Tampa, Florida, USA
| |
Collapse
|
16
|
Qiu YM, Zhang CL, Chen AQ, Wang HL, Zhou YF, Li YN, Hu B. Immune Cells in the BBB Disruption After Acute Ischemic Stroke: Targets for Immune Therapy? Front Immunol 2021; 12:678744. [PMID: 34248961 PMCID: PMC8260997 DOI: 10.3389/fimmu.2021.678744] [Citation(s) in RCA: 147] [Impact Index Per Article: 49.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 05/31/2021] [Indexed: 12/15/2022] Open
Abstract
Blood-Brain Barrier (BBB) disruption is an important pathophysiological process of acute ischemic stroke (AIS), resulting in devastating malignant brain edema and hemorrhagic transformation. The rapid activation of immune cells plays a critical role in BBB disruption after ischemic stroke. Infiltrating blood-borne immune cells (neutrophils, monocytes, and T lymphocytes) increase BBB permeability, as they cause microvascular disorder and secrete inflammation-associated molecules. In contrast, they promote BBB repair and angiogenesis in the latter phase of ischemic stroke. The profound immunological effects of cerebral immune cells (microglia, astrocytes, and pericytes) on BBB disruption have been underestimated in ischemic stroke. Post-stroke microglia and astrocytes can adopt both an M1/A1 or M2/A2 phenotype, which influence BBB integrity differently. However, whether pericytes acquire microglia phenotype and exert immunological effects on the BBB remains controversial. Thus, better understanding the inflammatory mechanism underlying BBB disruption can lead to the identification of more promising biological targets to develop treatments that minimize the onset of life-threatening complications and to improve existing treatments in patients. However, early attempts to inhibit the infiltration of circulating immune cells into the brain by blocking adhesion molecules, that were successful in experimental stroke failed in clinical trials. Therefore, new immunoregulatory therapeutic strategies for acute ischemic stroke are desperately warranted. Herein, we highlight the role of circulating and cerebral immune cells in BBB disruption and the crosstalk between them following acute ischemic stroke. Using a robust theoretical background, we discuss potential and effective immunotherapeutic targets to regulate BBB permeability after acute ischemic stroke.
Collapse
Affiliation(s)
| | | | | | | | | | - Ya-nan Li
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Bo Hu
- Department of Neurology, Union Hospital, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| |
Collapse
|
17
|
Sutter PA, Rouillard ME, Alshawi SA, Crocker SJ. Extracellular matrix influences astrocytic extracellular vesicle function in wound repair. Brain Res 2021; 1763:147462. [PMID: 33811843 DOI: 10.1016/j.brainres.2021.147462] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/15/2021] [Accepted: 03/29/2021] [Indexed: 02/08/2023]
Abstract
Astrocytic injury responses are known to be influenced by the extracellular matrix (ECM). Astrocytes are also recognized as a source of extracellular vesicles (EVs) that can impact the activity and function of other astrocytes and cell types. Whether the ECM influences the function of astrocytic EVs in the context of wound recovery has not been previously studied. We report EVs from astrocytes cultured on varied ECM substrates are sufficient to elicit distinct injury responses in naive astrocytes that recapitulate the effects of the ECM of origin. When compared with wound recovery on control substrates, EVs from ECM-exposed astrocytes elicited accelerated rates of wound recovery that varied based on each ECM. When EVs were collected from IL-1β treated and ECM-exposed astrocyte cultures, we found that IL-1β arrested wound recovery in naive astrocytes treated with EVs from astrocytes cultured on ECM but adding EVs from IL-1β treated Tenascin-c-cultured astrocytes increased wound recovery. To confirm that ECM was a primary influence on these astrocytic EV functions, we tested the contribution of β1-integrin, a major integrin receptor for the ECM molecules tested in this study. We found that the β1-integrin inhibitor Ha2/5, resulted in EVs that significantly attenuated the wound recovery of naive astrocytes. This provides new information on the importance of culture substrates on astrocytic responses, EV functions and injury responses that may impact the understanding of astroglial responses related to ECM compositional differences in diverse physiological states.
Collapse
Affiliation(s)
- Pearl A Sutter
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, United States
| | - Megan E Rouillard
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, United States
| | - Sarah A Alshawi
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, United States
| | - Stephen J Crocker
- Department of Neuroscience, University of Connecticut School of Medicine, Farmington, CT, United States; Department of Immunology, University of Connecticut School of Medicine, Farmington, CT, United States.
| |
Collapse
|
18
|
Zhan Y, Li MZ, Yang L, Feng XF, Lei JF, Zhang N, Zhao YY, Zhao H. The three-phase enriched environment paradigm promotes neurovascular restorative and prevents learning impairment after ischemic stroke in rats. Neurobiol Dis 2020; 146:105091. [DOI: 10.1016/j.nbd.2020.105091] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Revised: 08/30/2020] [Accepted: 09/21/2020] [Indexed: 02/06/2023] Open
|
19
|
Biswas S, Cottarelli A, Agalliu D. Neuronal and glial regulation of CNS angiogenesis and barriergenesis. Development 2020; 147:dev182279. [PMID: 32358096 PMCID: PMC7197727 DOI: 10.1242/dev.182279] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Neurovascular pathologies of the central nervous system (CNS), which are associated with barrier dysfunction, are leading causes of death and disability. The roles that neuronal and glial progenitors and mature cells play in CNS angiogenesis and neurovascular barrier maturation have been elucidated in recent years. Yet how neuronal activity influences these processes remains largely unexplored. Here, we discuss our current understanding of how neuronal and glial development affects CNS angiogenesis and barriergenesis, and outline future directions to elucidate how neuronal activity might influence these processes. An understanding of these mechanisms is crucial for developing new interventions to treat neurovascular pathologies.
Collapse
Affiliation(s)
- Saptarshi Biswas
- Departments of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Azzurra Cottarelli
- Departments of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
| | - Dritan Agalliu
- Departments of Neurology, Columbia University Irving Medical Center, New York, NY 10032, USA
- Pathology and Cell Biology, Columbia University Irving Medical Center, New York, NY 10032, USA
| |
Collapse
|
20
|
Gautam J, Xu L, Nirwane A, Nguyen B, Yao Y. Loss of mural cell-derived laminin aggravates hemorrhagic brain injury. J Neuroinflammation 2020; 17:103. [PMID: 32252790 PMCID: PMC7133020 DOI: 10.1186/s12974-020-01788-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2020] [Accepted: 03/25/2020] [Indexed: 02/05/2023] Open
Abstract
BACKGROUND Mural cells synthesize and deposit laminin to the basement membrane. To investigate the function of mural cell-derived laminin, we generated a mutant mouse line lacking mural cell-derived laminin (termed PKO). In a previous study, we showed that the PKO mice were grossly normal under homeostatic condition, but developed blood-brain barrier (BBB) breakdown with advanced age (> 8 months), suggesting that these mutants are intrinsically weak. Based on these findings, we hypothesized that PKO mice have exacerbated injuries in pathological conditions. METHODS Using collagenase-induced intracerebral hemorrhage (ICH) as an injury model, we examined various stroke outcomes, including hematoma volume, neurological function, neuronal death, BBB integrity, paracellular/transcellular transport, inflammatory cell infiltration, and brain water content, in PKO mice and their wildtype littermates at young age (6-8 weeks). In addition, transmission electron microscopy (TEM) analysis and an in vitro ICH model were used to investigate the underlying molecular mechanisms. RESULTS Compared to age-matched wildtype littermates, PKO mice display aggravated stroke outcomes, including larger hematoma size, worse neurological function, increased neuronal cell death, enhanced BBB permeability, increased transcytosis, and elevated inflammatory cell infiltration. These mutants also exhibit high baseline brain water content independent of aquaporin-4 (AQP4). In addition, mural cell-derived laminin significantly reduced caveolin-1 without affecting tight junction proteins in the in vitro ICH model. CONCLUSIONS These results suggest that mural cell-derived laminin attenuates BBB damage in ICH via decreasing caveolin-1 and thus transcytosis, regulates brain water homeostasis, and plays a beneficial role in ICH.
Collapse
Affiliation(s)
- Jyoti Gautam
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA, 30602, USA
| | - Lingling Xu
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA, 30602, USA
| | - Abhijit Nirwane
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA, 30602, USA
| | - Benjamin Nguyen
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA, 30602, USA
| | - Yao Yao
- Department of Pharmaceutical and Biomedical Sciences, University of Georgia, 240 W Green Street, Athens, GA, 30602, USA.
| |
Collapse
|
21
|
Affiliation(s)
- Minkyung Kang
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA
| | - Yao Yao
- From the Department of Pharmaceutical and Biomedical Sciences, University of Georgia, Athens, GA
| |
Collapse
|
22
|
Lu Z, Zhang D, Cui K, Fu X, Man J, Lu H, Yu L, Gao Y, Liu X, Liao L, Li X, Liu C, Zhang Y, Zhang Z, Wang J. Neuroprotective Action of Teriflunomide in a Mouse Model of Transient Middle Cerebral Artery Occlusion. Neuroscience 2019; 428:228-241. [PMID: 31887363 DOI: 10.1016/j.neuroscience.2019.12.011] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2019] [Revised: 12/04/2019] [Accepted: 12/08/2019] [Indexed: 12/11/2022]
Abstract
Teriflunomide has been reported to inhibit microglial activation in experimental models of traumatic brain injury. However, its roles in ischemic stroke and underlying mechanisms of action are still undiscovered. In this study, we investigated the effects of teriflunomide on brain edema, neurologic deficits, infarct volume, neuroinflammation, blood-brain barrier (BBB) permeability, and neurogenesis in a mouse model of transient middle cerebral artery occlusion (tMCAO). tMCAO mice treated with teriflunomide showed lower brain water content on day 3, milder neurologic deficits and smaller infarct volume on day 7 than those treated with vehicle. Additionally, mice received teriflunomide had fewer activated Iba-1-positive microglia and lower protein levels of interleukin-1β (IL-1β), cyclooxygenase-2 (COX-2), and 3-Nitrotyrosine (3-NT) compared with those received vehicle on day 3. Further, teriflunomide alleviated Evans blue dye leakage, increased pericyte coverage and protein levels of platelet-derived growth factor B (PDGFB), platelet-derived growth factor receptor β (PDGFRβ) and Bcl2, and decreased the number of PDGFRβ/matrix metalloproteinase 9 (MMP9)-positive cells. Moreover, teriflunomide reduced the loss of zonula occludens-1 (ZO-1) and occludin. Finally, teriflunomide significantly upregulated the number of 5-bromo-20-deoxyuridine (BrdU)/doublecortin (DCX)-positive cells and expression of mammalian achaete-scute homolog 1 (Mash1), DCX and Pbx1 in subventricular zone (SVZ) on day 7 after stroke. Our results indicate that teriflunomide exhibits protective roles in ischemic stroke by inhibiting neuroinflammation, alleviating BBB disruption and enhancing neurogenesis.
Collapse
Affiliation(s)
- Zhengfang Lu
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Di Zhang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Kefei Cui
- Department of Ultrasound, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Xiaojie Fu
- Department of Neurointervention, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Jiang Man
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Hong Lu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Lie Yu
- Department of Neurology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Yufeng Gao
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Xianliang Liu
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Linghui Liao
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Xiang Li
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Chang Liu
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Yongxin Zhang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Zhen Zhang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China
| | - Jianping Wang
- Department of Neurology, The Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou 450052 Henan Province, China.
| |
Collapse
|
23
|
Pericytic Laminin Maintains Blood-Brain Barrier Integrity in an Age-Dependent Manner. Transl Stroke Res 2019; 11:228-242. [PMID: 31292838 DOI: 10.1007/s12975-019-00709-8] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2019] [Revised: 05/22/2019] [Accepted: 05/30/2019] [Indexed: 02/05/2023]
Abstract
Brain pericytes synthesize and deposit laminin at the blood-brain barrier (BBB). The function of pericyte-derived laminin in BBB maintenance remains largely unknown. In a previous study, we generated pericytic laminin conditional knockout (PKO) mice, which developed BBB breakdown and hydrocephalus in a mixed genetic background. However, since hydrocephalus itself can compromise BBB integrity, it remains unclear whether BBB disruption in these mutants is due to loss of pericytic laminin or secondary to hydrocephalus. Here, we report that, in C57Bl6 dominant background, the PKO mice fail to show hydrocephalus, have a normal lifespan, and develop BBB breakdown in an age-dependent manner. Further mechanistic studies demonstrate that abnormal paracellular transport, enhanced transcytosis, decreased pericyte coverage, and diminished AQP4 level are responsible for BBB disruption in PKO mice. These results suggest that pericyte-derived laminin plays an indispensable and age-dependent role in the maintenance of BBB integrity under homeostatic conditions.
Collapse
|