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Chin JS, Milbreta U, Becker DL, Chew SY. Targeting connexin 43 expression via scaffold mediated delivery of antisense oligodeoxynucleotide preserves neurons, enhances axonal extension, reduces astrocyte and microglial activation after spinal cord injury. J Tissue Eng 2023; 14:20417314221145789. [PMID: 36798907 PMCID: PMC9926388 DOI: 10.1177/20417314221145789] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2022] [Accepted: 12/01/2022] [Indexed: 02/12/2023] Open
Abstract
Injury to the central nervous system (CNS) provokes an inflammatory reaction and secondary damage that result in further tissue damage and destruction of neurons away from the injury site. Upon injury, expression of connexin 43 (Cx43), a gap junction protein, upregulates and is responsible for the spread and amplification of cell death signals through these gap junctions. In this study, we hypothesise that the downregulation of Cx43 by scaffold-mediated controlled delivery of antisense oligodeoxynucleotide (asODN), would minimise secondary injuries and cell death, and thereby support tissue regeneration after nerve injuries. Specifically, using spinal cord injury (SCI) as a proof-of-principle, we utilised a fibre-hydrogel scaffold for sustained delivery of Cx43asODN, while providing synergistic topographical cues to guide axonal ingrowth. Correspondingly, scaffolds loaded with Cx43asODN, in the presence of NT-3, suppressed Cx43 up-regulation after complete transection SCI in rats. These scaffolds facilitated the sustained release of Cx43asODN for up to 25 days. Importantly, asODN treatment preserved neurons around the injury site, promoted axonal extension, decreased glial scarring, and reduced microglial activation after SCI. Our results suggest that implantation of such scaffold-mediated asODN delivery platform could serve as an effective alternative SCI therapeutic approach.
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Affiliation(s)
- Jiah Shin Chin
- Nanyang Institute of Health Technologies, Interdisciplinary Graduate School, Nanyang Technological University, Singapore,School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - Ulla Milbreta
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore
| | - David L Becker
- Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore,Skin Research Institute Singapore, Clinical Sciences Building, Singapore
| | - Sing Yian Chew
- School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, Singapore,Lee Kong Chian School of Medicine, Nanyang Technological University, Singapore,School of Materials Science and Engineering, Nanyang Technological University, Singapore,Sing Yian Chew, School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, 639798, Singapore.
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Rodgers KR, Lin Y, Langan TJ, Iwakura Y, Chou RC. Innate Immune Functions of Astrocytes are Dependent Upon Tumor Necrosis Factor-Alpha. Sci Rep 2020; 10:7047. [PMID: 32341377 PMCID: PMC7184618 DOI: 10.1038/s41598-020-63766-2] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 03/25/2020] [Indexed: 12/31/2022] Open
Abstract
Acute inflammation is a key feature of innate immunity that initiates clearance and repair in infected or damaged tissues. Alternatively, chronic inflammation is implicated in numerous disease processes. The contribution of neuroinflammation to the pathogenesis of neurological conditions, including infection, traumatic brain injury, and neurodegenerative diseases, has become increasingly evident. Potential drivers of such neuroinflammation include toll-like receptors (TLRs). TLRs confer a wide array of functions on different cell types in the central nervous system (CNS). Importantly, how TLR activation affects astrocyte functioning is unclear. In the present study, we examined the role of TLR2/4 signaling on various astrocyte functions (i.e., proliferation, pro-inflammatory mediator production, regulatory mechanisms, etc) by stimulating astrocytes with potent exogenous TLR2/4 agonist, bacterial lipopolysaccharide (LPS). Newborn astrocytes were derived from WT, Tnfα−/−, Il1α−/−/Il1β−/−, and Tlr2−/−/Tlr4−/− mice as well as Sprague Dawley rats for all in vitro studies. LPS activated mRNA expression of different pro-inflammatory cytokines and chemokines in time- and concentration-dependent manners, and upregulated the proliferation of astrocytes based on increased 3H-thymidine update. Following LPS-mediated TLR2/4 activation, TNF-α and IL-1β self-regulated and modulated the expression of pro-inflammatory cytokines and chemokines. Polyclonal antibodies against TNF-α suppressed TLR2/4-mediated upregulation of astrocyte proliferation, supporting an autocrine/paracrine role of TNF-α on astrocyte proliferation. Astrocytes perform classical innate immune functions, which contradict the current paradigm that microglia are the main immune effector cells of the CNS. TNF-α plays a pivotal role in the LPS-upregulated astrocyte activation and proliferation, supporting their critical roles in in CNS pathogenesis.
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Affiliation(s)
- Kyla R Rodgers
- Department of Medicine, Geisel School of Medicine at Dartmouth, Dartmouth College, One Medical Center Drive, Lebanon, NH, 03756, USA
| | - Yufan Lin
- Department of Medicine, Geisel School of Medicine at Dartmouth, Dartmouth College, One Medical Center Drive, Lebanon, NH, 03756, USA
| | - Thomas J Langan
- Departments of Neurology, Pediatrics, and Physiology and Biophysics, Jacobs School of Medicine and Biomedical Sciences, State University of New York at Buffalo, Buffalo, NY, 14203, USA.,Hunter James Kelly Research Institute, New York State Center of Excellence Bioinformatics & Life Sciences, Buffalo, NY, 14203, USA
| | - Yoichiro Iwakura
- Research Institute for Biomedical Sciences, Tokyo University of Science, 2669 Yamazaki, Chiba, 278-0022, Japan
| | - Richard C Chou
- Department of Medicine, Geisel School of Medicine at Dartmouth, Dartmouth College, One Medical Center Drive, Lebanon, NH, 03756, USA.
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Chun H, An H, Lim J, Woo J, Lee J, Ryu H, Lee CJ. Astrocytic proBDNF and Tonic GABA Distinguish Active versus Reactive Astrocytes in Hippocampus. Exp Neurobiol 2018; 27:155-170. [PMID: 30022867 PMCID: PMC6050417 DOI: 10.5607/en.2018.27.3.155] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Revised: 06/26/2018] [Accepted: 06/30/2018] [Indexed: 01/18/2023] Open
Abstract
Astrocytes are the most abundant cell type in the brain and they make close contacts with neurons and blood vessels. They respond dynamically to various environmental stimuli and change their morphological and functional properties. Both physiological and pathological stimuli can induce versatile changes in astrocytes, as this phenomenon is referred to as ‘astrocytic plasticity’. However, the molecular and cellular mechanisms of astrocytic plasticity in response to various stimuli remain elusive, except for the presence of hypertrophy, a conspicuous structural change which is frequently observed in activated or reactive astrocytes. Here, we investigated differential characteristics of astrocytic plasticity in a stimulus-dependent manner. Strikingly, a stab wound brain injury lead to hypertrophy of astrocytes accompanied by increased GABA expression and tonic GABA release in mouse CA1 hippocampus. In contrast, the mice experiencing enriched environment exhibited astrocytic hypertrophy with enhanced proBDNF immunoreactivity but without GABA signal. Based on the results, we define proBDNF-positive/GABA-negative hypertrophic astrocytes as ‘active’ astrocytes and GABA-positive hypertrophic astrocytes as ‘reactive’ astrocytes, respectively. We propose for the first time that astrocytic proBDNF can be a bona fide molecular marker of the active astrocytes, which are distinct from the reactive astrocytes which show hypertrophy but with aberrant GABA.
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Affiliation(s)
- Heejung Chun
- Center for Neuroscience and Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.,Center for Glia-Neuron Interaction, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Heeyoung An
- Center for Neuroscience and Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.,Center for Glia-Neuron Interaction, Brain Science Institute, KIST, Seoul 02792, Korea.,KU-KIST Graduate School of Converging Science and Technology, Korea University, Seoul 02841, Korea
| | - Jiwoon Lim
- Center for Glia-Neuron Interaction, Brain Science Institute, KIST, Seoul 02792, Korea
| | - Junsung Woo
- Center for Neuroscience and Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
| | - Jaekwang Lee
- Center for Neuroscience and Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea
| | - Hoon Ryu
- Center for Neuromedicine, Brain Science Institute, KIST, Seoul 02792, Korea.,Boston University Alzheimer's Disease Center and Department of Neurology, Boston University School of Medicine, Boston, MA 02118, USA
| | - C Justin Lee
- Center for Neuroscience and Functional Connectomics, Brain Science Institute, Korea Institute of Science and Technology (KIST), Seoul 02792, Korea.,Center for Glia-Neuron Interaction, Brain Science Institute, KIST, Seoul 02792, Korea.,Division of Bio-Medical Science & Technology, KIST School, KIST, Seoul 02792, Korea
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Neuronal Regeneration after Electroacupuncture Treatment in Ischemia-Reperfusion-Injured Cerebral Infarction Rats. BIOMED RESEARCH INTERNATIONAL 2017; 2017:3178014. [PMID: 28913350 PMCID: PMC5587926 DOI: 10.1155/2017/3178014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Revised: 06/27/2017] [Accepted: 07/20/2017] [Indexed: 01/30/2023]
Abstract
Adult neuronal cells which can regenerate have been reported. The present study investigated whether acupuncture enhances neuronal regeneration in ischemic stroke rats. We established an ischemic stroke rat model by occluding the cerebral blood flow of the right middle cerebral artery for 15 minutes and then allowing reperfusion in Sprague–Dawley rats. The results indicated that, in these rats, 2 Hz electroacupuncture (EA) at both Zusanli (ST36) and Shangjuxu (ST37) acupoints reduced the infarction/hemisphere ratio 8 days after reperfusion and reduced the modified neurological severity score (mNSS) and increased the rotarod test time 4 and 8 days after reperfusion, respectively. In addition, 2 Hz reduced nestin immunoreactive cells in the penumbra area and the ischemic core area; 2 Hz EA also reduced Ki67 immunoreactive cells and increased glial fibrillary acidic protein immunoreactive cells in the penumbra area. These findings suggest that 2 Hz EA at the ST36 and ST37 acupoints has a neuroprotective role. However, additional studies are needed to further investigate these preliminary results.
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Lee HH, Park SC, Choe IS, Kim Y, Ha YS. Time Course and Characteristics of Astrocyte Activation in the Rat Brain after Injury. Korean J Neurotrauma 2015; 11:44-51. [PMID: 27169064 PMCID: PMC4847494 DOI: 10.13004/kjnt.2015.11.2.44] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2015] [Revised: 09/04/2015] [Accepted: 09/05/2015] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE After injury to the central nervous system (CNS), glial scar tissue is formed in the process of wound healing. This can be is a clinical problem because it interferes with axonal regeneration and functional recovery. It is known that intracellular proteins, including the glial fibrillary acidic protein (GFAP), nestin, and vimentin increase in the astrocytes after an injury to the CNS. By studying the time course and co-expression pattern of these intracellular proteins, this study will attempt to prove that these proteins are involved in the processes of glial scar formation. METHODS Twenty-five male Sprague-Dawley rats were used in this study. Bregma of the cerebral cortex, an area was incised with a sharp blade, and perfusion was performed. The expressions of the intracellular proteins were assayed, while the co-localization of the intermediate filament (GFAP, nestin, and vimentin) and A2B5 were examined. RESULTS At 12 hours, the GFAP was expressed in the white matter underlying the lesion, and in the cerebral cortex. Nestin was expressed in the astrocytes in the perilesional area after 3 days, while A2B5 was observed in the edge of the wound at 12 hours post-injury, with its expression reaching a peak at 7 days. Vimentin was detected in the white matter at 12 hours, and in the cortex, reaching a peak at 7 days. CONCLUSION In the processes of glial scar formation, nestin, vimentin, and A2B5 were revealed in the astrocytes, and these factors may be involved in the division, proliferation, and transportation of the astrocytes.
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Affiliation(s)
- Hyun-Ho Lee
- Department of Neurosurgery, Myongji Hospital, Goyang, Korea
| | | | - Il-Seung Choe
- Department of Neurosurgery, Myongji Hospital, Goyang, Korea
| | - Young Kim
- Department of Neurosurgery, Myongji Hospital, Goyang, Korea
| | - Young-Soo Ha
- Department of Neurosurgery, Myongji Hospital, Goyang, Korea
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Chang KW, Huang YL, Wong ZR, Su PH, Huang BM, Ju TK, Yang HY. Fibroblast growth factor-2 up-regulates the expression of nestin through the Ras-Raf-ERK-Sp1 signaling axis in C6 glioma cells. Biochem Biophys Res Commun 2013; 434:854-60. [PMID: 23611784 DOI: 10.1016/j.bbrc.2013.04.031] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Accepted: 04/04/2013] [Indexed: 11/30/2022]
Abstract
Nestin is a 240-kDa intermediate filament protein expressed mainly in neural and myogenic stem cells. Although a substantial number of studies have focused on the expression of nestin during development of the central nervous system, little is known about the factors that induce and regulate its expression. Fibroblast growth factor-2 (FGF-2) is an effective mitogen and stimulates the proliferation and differentiation of a subset of nestin-expressing cells, including neural progenitor cells, glial precursor cells, and smooth muscle cells. To assess whether FGF-2 is a potent factor that induces the expression of nestin, C6 glioma cells were used. The results showed that nestin expression was up-regulated by FGF-2 via de novo RNA and protein synthesis. Our RT-PCR results showed that C6 glioma cells express FGFR1/3, and FGFRs is required for FGF-2-induced nestin expression. Further signaling analysis also revealed that FGF-2-induced nestin expression is mediated through FGFR-MAPK-ERK signaling axis and the transcriptional factor Sp1. These findings provide new insight into the regulation of nestin in glial system and enable the further studies on the function of nestin in glial cells.
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Affiliation(s)
- Kai-Wei Chang
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 106, Taiwan
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Su PH, Chen CC, Chang YF, Wong ZR, Chang KW, Huang BM, Yang HY. Identification and cytoprotective function of a novel nestin isoform, Nes-S, in dorsal root ganglia neurons. J Biol Chem 2013; 288:8391-8404. [PMID: 23319587 DOI: 10.1074/jbc.m112.408179] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
In this study, the first nestin isoform, Nes-S, was identified in neurons of dorsal root ganglia (DRG) of adult rats. Nes-S cannot form filaments by itself in cytoplasmic intermediate filament-free SW13 cells. Instead, it co-assembles into filaments with vimentin when transfected into vimentin(+) SW13 cells, and with peripherin and neurofilament proteins when transfected into N2a cells. In primary DRG neurons, endogenous Nes-S co-assembles with peripherin and neurofilament proteins. The expression of Nes-S first appears in DRG at postnatal day 5 and persists to adulthood. Among the adult tissues we examined, the expression of Nes-S is restricted to the sensory and motor neurons. Finally, exogenous Nes-S enhances viability when transfected into N2a cells, and knockdown of endogenous Nes-S impairs the survival of DRG neurons in primary cultures. Taken together, Nes-S is a new neuronal intermediate filament protein that exerts a cytoprotective function in mature sensory and motor neurons.
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Affiliation(s)
- Peng-Han Su
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan
| | - Chih-Cheng Chen
- Institute of Biomedical Sciences, Academia Sinica, Taipei 115, Taiwan
| | - Ya-Fan Chang
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan
| | - Zong-Ruei Wong
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan
| | - Kai-Wei Chang
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan
| | - Bu-Miin Huang
- Department of Cell Biology and Anatomy, National Cheng-Kung University, Tainan 701, Taiwan
| | - Hsi-Yuan Yang
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei 10617, Taiwan.
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Su PH, Wang TC, Wong ZR, Huang BM, Yang HY. The expression of nestin delineates skeletal muscle differentiation in the developing rat esophagus. J Anat 2011; 218:311-23. [PMID: 21323914 DOI: 10.1111/j.1469-7580.2010.01331.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
The muscularis externa of the developing rodent esophagus is initially composed of smooth muscle, and later replaced by skeletal muscle in a craniocaudal progression. There is growing evidence of distinct developmental origins for esophageal smooth and skeletal muscles. However, the identification of skeletal muscle progenitor cells is controversial, and the detailed cell lineage of their descendants remains elusive. In the current study, we carried out multiple labeling immunofluorescence microscopy of nestin and muscle type-specific markers to characterize the dynamic process of rat esophageal myogenesis. The results showed that nestin was transiently expressed in immature esophageal smooth muscle cells in early developing stages. After nestin was downregulated in smooth muscle cells, a distinct population of nestin-positive cells emerged as skeletal muscle precursors. They were mitotically active, and subsequently co-expressed MyoD, followed by the embryonic and later the fast type of skeletal muscle myosin heavy chain. Thus, the cell lineage of esophageal skeletal muscle differentiation was established by an immunotyping approach, which revealed that skeletal myocytes arise from a distinct lineage rather than through transdifferentiation of smooth muscle cells during rat esophageal myogenesis.
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Affiliation(s)
- Peng-Han Su
- Institute of Molecular and Cellular Biology, National Taiwan University, Taipei, Taiwan
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Holmberg E, Zhang SX, Sarmiere PD, Kluge BR, White JT, Doolen S. Statins decrease chondroitin sulfate proteoglycan expression and acute astrocyte activation in central nervous system injury. Exp Neurol 2008; 214:78-86. [DOI: 10.1016/j.expneurol.2008.07.020] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2008] [Revised: 06/24/2008] [Accepted: 07/18/2008] [Indexed: 12/27/2022]
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Haupt C, Witte OW, Frahm C. Up-regulation of Connexin43 in the glial scar following photothrombotic ischemic injury. Mol Cell Neurosci 2007; 35:89-99. [PMID: 17350281 DOI: 10.1016/j.mcn.2007.02.005] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2006] [Revised: 12/29/2006] [Accepted: 02/05/2007] [Indexed: 11/29/2022] Open
Abstract
Several types of CNS injury and various diseases are associated with the development of a glial scar. Astrocytes are major components of the glial scar. They are interconnected by gap junctions, with connexin43 (Cx43) being the most prominent channel protein. We applied a model of focal cerebral ischemia to study the spatio-temporal expression of glial fibrillary acidic protein, as well as of Cx43 mRNA and protein in gliotic tissue up to 60 days after injury. Reactive astrocytes enveloping the lesion up-regulated their Cx43 mRNA and protein. A band of reactive astrocytes filling in the lesion exhibited elevated Cx43 and showed a high degree of proliferation. Because of these findings, we hypothesize a role for Cx43 in glial scar formation, specifically in the proliferation of astrocytes.
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Affiliation(s)
- Corinna Haupt
- Department of Neurology, Friedrich-Schiller-University, Erlanger Allee 101, 07747 Jena, Germany
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Haupt C, Witte OW, Frahm C. Temporal profile of connexin 43 expression after photothrombotic lesion in rat brain. Neuroscience 2007; 144:562-70. [PMID: 17112677 DOI: 10.1016/j.neuroscience.2006.09.054] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2006] [Revised: 09/29/2006] [Accepted: 09/30/2006] [Indexed: 11/20/2022]
Abstract
Following focal ischemic injury, several mechanisms lead to secondary expansion of the affected area and therefore increase the initial damage. We thoroughly investigated the expression of astrocytic connexin 43 (Cx43) after photothrombosis in rat brain. The temporal profile of Cx43 mRNA as well as protein expression was studied in remote, structurally uninjured cortical and hippocampal areas. The hippocampal formation revealed an increased number of Cx43 mRNA positive astrocytes and an up-regulated protein expression exclusively in the ipsilateral stratum oriens. We assume a participation of this region in glia scar formation. While Cx43 mRNA positive cells were transiently increased, immunoreactivity was reduced in the somatosensory cortex of injured hemispheres. The observed decrease of Cx43 protein in the post-ischemic cerebral cortex implies an impairment of gap junctional intercellular communication which might be detrimental to the brain.
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Affiliation(s)
- C Haupt
- Department of Neurology, Friedrich-Schiller-University, Erlanger Allee 101, 07747 Jena, Germany
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Hayashi N, Miyata S, Kariya Y, Takano R, Hara S, Kamei K. Attenuation of glial scar formation in the injured rat brain by heparin oligosaccharides. Neurosci Res 2004; 49:19-27. [PMID: 15099700 DOI: 10.1016/j.neures.2004.01.007] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2003] [Accepted: 01/16/2004] [Indexed: 11/25/2022]
Abstract
Injury to the central nervous system causes glial reactions, which eventually lead to the formation of a glial scar and inhibit axonal regeneration. The present study aimed to reduce the extent of glial scar formation in injured cerebral cortex using heparin hexasaccharide (6-mer) and octasaccharide (8-mer). A single injection of 20 microl of heparin 6-mer or heparin 8-mer (10mg/ml), native heparin (10mg/ml), or saline vehicle was given into the wound cavity just after cryo-injury in the cerebral cortex. In saline-injected control rats, strong chondroitin sulfate-A (CS-A) immunoreactivity using 2H6 antibody was observed around the injured site. Double labeling using an antibody against glial fibrillary acidic protein, a glial marker, further demonstrated that CS-A immunoreactivity was mainly expressed on the reactive astrocytes at the glial scar, indicating that CS-A immunohistochemistry is useful for evaluating glial scar formation. Quantitative morphometrical analysis revealed that the area of CS-A immunoreactivity was significantly decreased by 53% in heparin-6-mer-injected animals and 44% in heparin-8-mer-injected ones 6 days after the injury, but native heparin had no effect on CS-A-immunoreactive areas. Both heparin oligosaccharides also attenuated the intensity of CS-A immunoreactivity in the reactive astrocytes and caused astrocytic cellular processes to be less branched. These results demonstrate that a single injection of heparin oligosaccharides attenuates glial scar formation, indicating that heparin oligosaccharides may be applicable to many fibrotic diseases and restore functional integrity.
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Affiliation(s)
- Noriko Hayashi
- Department of Applied Biology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto 606-8585, Japan
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