1
|
Cheng Y, Lin D, Wu S, Liu Q, Yan X, Ren T, Zhang J, Wang N. Cerebrospinal Fluid Pressure Reduction Induces Glia-Mediated Retinal Inflammation and Leads to Retinal Ganglion Cell Injury in Rats. Mol Neurobiol 2023; 60:5770-5788. [PMID: 37347366 DOI: 10.1007/s12035-023-03430-8] [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: 02/01/2023] [Accepted: 06/05/2023] [Indexed: 06/23/2023]
Abstract
Low intracranial pressure (LICP)-induced translaminar cribrosa pressure difference (TLCPD) elevation has been proven as a risk factor in glaucomatous neurodegeneration, whereas the underlying retinal immune features of LICP-induced retinal ganglion cells (RGC) injury remain elusive. Here, we identified the retinal immune characteristics of LICP rats, and minocycline (Mino) treatment was utilized to analyze its inhibitory role in glia-mediated retinal inflammation of LICP rats. The results showed that retrograde axonal transport was decreased in LICP rats without significant RGC loss, indicating the RGC injury was at an early stage before the morphological loss. The activation of retinal microglia and astrocytes with morphologic and M1 or A1-marker alternations was detected in TLCPD elevation rats, the activation level is more dramatic in HIOP rats than in the LICP rats (P<0.05). Besides, we detected reduced retinal tight junction protein expressions, accompanied by specific imbalance patterns of T lymphocytes in the retina of both LICP and HIOP rats (P<0.05). Further Mino treatment showed an effective inhibitory role in glia-driven inflammatory responses in LICP rats, including improving retrograde axonal transport, inhibiting retinal glial activation and proinflammatory subtype polarization, and alleviating the blood-retina barrier compromise. This study identified the glia-mediated retinal inflammation features triggered by LICP stimulus, and Mino application exhibited an effective role in the inhibition of retinal glia-mediated inflammation in LICP-induced TLCPD elevation rats.
Collapse
Affiliation(s)
- Ying Cheng
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
- Department of Ophthalmology, The First Affiliated Hospital of Xi'an Jiaotong University, Xi'an, 710061, China
| | - Danting Lin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Shen Wu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Qian Liu
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Xuejing Yan
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Tianmin Ren
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China
| | - Jingxue Zhang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China.
- Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China.
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing, 100069, China.
| | - Ningli Wang
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Laboratory, Beijing, 100730, China.
- Beijing Institute of Brain Disorders, Collaborative Innovation Center for Brain Disorders, Capital Medical University, Beijing, 100069, China.
- Beijing Key Laboratory of Fundamental Research on Biomechanics in Clinical Application, Capital Medical University, Beijing, 100069, China.
| |
Collapse
|
2
|
Optimisation of AAV-NDI1 Significantly Enhances Its Therapeutic Value for Correcting Retinal Mitochondrial Dysfunction. Pharmaceutics 2023; 15:pharmaceutics15020322. [PMID: 36839646 PMCID: PMC9960502 DOI: 10.3390/pharmaceutics15020322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 12/27/2022] [Accepted: 01/07/2023] [Indexed: 01/20/2023] Open
Abstract
AAV gene therapy for ocular disease has become a reality with the market authorisation of LuxturnaTM for RPE65-linked inherited retinal degenerations and many AAV gene therapies currently undergoing phase III clinical trials. Many ocular disorders have a mitochondrial involvement from primary mitochondrial disorders such as Leber hereditary optic neuropathy (LHON), predominantly due to mutations in genes encoding subunits of complex I, to Mendelian and multifactorial ocular conditions such as dominant optic atrophy, glaucoma and age-related macular degeneration. In this study, we have optimised the nuclear yeast gene, NADH-quinone oxidoreductase (NDI1), which encodes a single subunit complex I equivalent, creating a candidate gene therapy to improve mitochondrial function, independent of the genetic mutation driving disease. Optimisation of NDI1 (ophNdi1) substantially increased expression in vivo, protected RGCs and increased visual function, as assessed by optokinetic and photonegative response, in a rotenone-induced murine model. In addition, ophNdi1 increased cellular oxidative phosphorylation and ATP production and protected cells from rotenone insult to a significantly greater extent than wild type NDI1. Significantly, ophNdi1 treatment of complex I deficient patient-derived fibroblasts increased oxygen consumption and ATP production rates, demonstrating the potential of ophNdi1 as a candidate therapy for ocular disorders where mitochondrial deficits comprise an important feature.
Collapse
|
3
|
Wang L, Wei X. T Cell-Mediated Autoimmunity in Glaucoma Neurodegeneration. Front Immunol 2022; 12:803485. [PMID: 34975917 PMCID: PMC8716691 DOI: 10.3389/fimmu.2021.803485] [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: 10/28/2021] [Accepted: 12/01/2021] [Indexed: 02/05/2023] Open
Abstract
Glaucoma as the leading neurodegenerative disease leads to blindness in 3.6 million people aged 50 years and older worldwide. For many decades, glaucoma therapy has primarily focused on controlling intraocular pressure (IOP) and sound evidence supports its role in delaying the progress of retinal ganglial cell (RGC) damage and protecting patients from vision loss. Meanwhile, accumulating data point to the immune-mediated attack of the neural retina as the underlying pathological process behind glaucoma that may come independent of raised IOP. Recently, some scholars have suggested autoimmune aspects in glaucoma, with autoreactive T cells mediating the chief pathogenic process. This autoimmune process, as well as the pathological features of glaucoma, largely overlaps with other neurodegenerative diseases in the central nervous system (CNS), including Alzheimer’s disease, Parkinson’s disease, and multiple sclerosis. In addition, immune modulation therapy, which is regarded as a potential solution for glaucoma, has been boosted in trials in some CNS neurodegenerative diseases. Thus, novel insights into the T cell-mediated immunity and treatment in CNS neurodegenerative diseases may serve as valuable inspirations for ophthalmologists. This review focuses on the role of T cell-mediated immunity in the pathogenesis of glaucoma and discusses potential applications of relevant findings of CNS neurodegenerative diseases in future glaucoma research.
Collapse
Affiliation(s)
- Lixiang Wang
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China
| | - Xin Wei
- Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China.,Department of Ophthalmology, Shangjin Nanfu Hospital, Chengdu, China
| |
Collapse
|
4
|
Ly6c as a New Marker of Mouse Blood Vessels: Qualitative and Quantitative Analyses on Intact and Ischemic Retinas. Int J Mol Sci 2021; 23:ijms23010019. [PMID: 35008441 PMCID: PMC8744623 DOI: 10.3390/ijms23010019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Revised: 12/14/2021] [Accepted: 12/16/2021] [Indexed: 12/01/2022] Open
Abstract
Ly6c is an antigen commonly used to differentiate between classical and non-classical monocytes/macrophages. Here we show its potential as a marker of the mouse vasculature, particularly of the retinal vascular plexuses. Ly6c was immunodetected in several tissues of C57BL/6 mice using isolectin IB4 as the control of vasculature staining. In the retina, Ly6c expression was analyzed qualitatively and quantitatively in intact, ischemic, and contralateral retinas from 0 to 30 days after the insult. Ly6c expression was observed in all organs and tissues tested, with a brighter signal and more homogeneous staining than the IB4. In the retinas, Ly6c was well expressed, allowing a detailed study of their anatomy. The three retinal plexuses were morphologically different, and from the superficial to the deep one occupied 15 ± 2, 24 ± 7, and 38 ± 1.4 percent of the retinal surface, respectively. In the injured retinas, there was extravasation of the classically activated monocyte/macrophages (Ly6chigh) and the formation of new vessels in the superficial plexus, increasing the area occupied by it to 25 ± 1%. In the contralateral retinas, the superficial plexus area decreased gradually, reaching significance at 30 days, and Ly6c expression progressively disappeared in the intermediate and deep plexuses. Although the role of Ly6c in vascular endothelial cell function is still not completely understood, we demonstrate here that Ly6c can be used as a new specific marker of the mouse vasculature and to assess, qualitatively and quantitatively, vascular changes in health and disease.
Collapse
|
5
|
Trost A, Motloch K, Koller A, Bruckner D, Runge C, Schroedl F, Bogner B, Kaser-Eichberger A, Strohmaier C, Ladek AM, Preishuber-Pfluegl J, Brunner SM, Aigner L, Reitsamer HA. Inhibition of the cysteinyl leukotriene pathways increases survival of RGCs and reduces microglial activation in ocular hypertension. Exp Eye Res 2021; 213:108806. [PMID: 34715090 DOI: 10.1016/j.exer.2021.108806] [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: 05/26/2021] [Revised: 08/05/2021] [Accepted: 10/21/2021] [Indexed: 10/20/2022]
Abstract
Glaucoma is the second leading cause of blindness worldwide. This multifactorial, neurodegenerative group of diseases is characterized by the progressive loss of retinal ganglion cells (RGCs) and their axons, leading to irreversible visual impairment and blindness. There is a huge unmet and urging need for the development of new and translatable strategies and treatment options to prevent this progressive loss of RGC. Accumulating evidence points towards a critical role of neuroinflammation, in particular microglial cells, in the pathogenesis of glaucoma. Leukotrienes are mediators of neuroinflammation and are involved in many neurodegenerative diseases. Therefore, we tested the leukotriene receptors CysLT1R/GPR17-selective antagonist Montelukast (MTK) for its efficacy to modulate the reactive state of microglia in order to ameliorate RGCs loss in experimental glaucoma. Ocular hypertension (OHT) was induced unilaterally by injection of 8 μm magnetic microbead (MB) into the anterior chamber of female Brown Norway rats. The contralateral, untreated eye served as control. Successful induction of OHT was verified by daily IOP measurement using a TonoLab rebound tonometer. Simultaneously to OHT induction, one group received daily MTK treatment and the control group vehicle solution by oral gavage. Animals were sacrificed 13-15 days after MB injection. Retina and optic nerves (ON) of OHT and contralateral eyes were analyzed by immunofluorescence with specific markers for RGCs (Brn3a), microglial cells/macrophages (Iba1 and CD68), and cysteinyl leukotriene pathway receptors (CysLT1R and GPR17). Protein labeling was documented by confocal microscopy and analyzed with ImageJ plugins. Further, mRNA expression of genes of the inflammatory and leukotriene pathway was analyzed in retinal tissue. MTK treatment resulted in a short-term IOP reduction at day 2, which dissipated by day 5 of OHT induction in MTK treated animals. Furthermore, MTK treatment resulted in a decreased activation of Iba1+ microglial cells in the retina and ON, and in a significantly increased RGC survival in OHT eyes. Within the retina, GPR17 and CysLT1R expression was demonstrated in single RCGs and in microglial cells respectively. Further, increased mRNA expression of pro-inflammatory genes was detected in OHT induced retinas. In the ON, OHT induction increased the number of GPR17+ cells, showing a trend of reduction following MTK treatment. This study shows for the first time a significantly increased RGC survival in an acute OHT model following treatment with the leukotriene receptor antagonist MTK. These results strongly suggest a neuroprotective effect of MTK and a potential new therapeutic strategy for glaucoma treatment.
Collapse
Affiliation(s)
- Andrea Trost
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria.
| | - Karolina Motloch
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Andreas Koller
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Daniela Bruckner
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Christian Runge
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Falk Schroedl
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria; Center for Anatomy and Cell Biology, Institute of Anatomy and Cell Biology - Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Barbara Bogner
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Alexandra Kaser-Eichberger
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria; Center for Anatomy and Cell Biology, Institute of Anatomy and Cell Biology - Salzburg, Paracelsus Medical University, Salzburg, Austria
| | - Clemens Strohmaier
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria; Department of Ophthalmology and Optometry, Johannes Kepler University, Linz, Austria
| | - Anja-Maria Ladek
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Julia Preishuber-Pfluegl
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Susanne Maria Brunner
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria
| | - Ludwig Aigner
- Institute of Molecular Regenerative Medicine, Paracelsus Medical University, Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University Salzburg, Austria
| | - Herbert Anton Reitsamer
- University Clinic of Ophthalmology and Optometry, Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, 5020, Salzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University Salzburg, Austria
| |
Collapse
|
6
|
Blood-retinal barrier as a converging pivot in understanding the initiation and development of retinal diseases. Chin Med J (Engl) 2021; 133:2586-2594. [PMID: 32852382 PMCID: PMC7722606 DOI: 10.1097/cm9.0000000000001015] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Clinical ophthalmologists consider each retinal disease as a completely unique entity. However, various retinal diseases, such as uveitis, age-related macular degeneration, diabetic retinopathy, and primary open-angle glaucoma, share a number of common pathogenetic pathways. Whether a retinal disease initiates from direct injury to the blood-retinal barrier (BRB) or a defect/injury to retinal neurons or glia that impairs the BRB secondarily, the BRB is a pivotal point in determining the prognosis as self-limiting and recovering, or developing and progressing to a clinical phenotype. The present review summarizes our current knowledge on the physiology and cellular and molecular pathology of the BRB, which underlies its pivotal role in the initiation and development of common retinal diseases.
Collapse
|
7
|
Quaranta L, Bruttini C, Micheletti E, Konstas AGP, Michelessi M, Oddone F, Katsanos A, Sbardella D, De Angelis G, Riva I. Glaucoma and neuroinflammation: An overview. Surv Ophthalmol 2021; 66:693-713. [PMID: 33582161 DOI: 10.1016/j.survophthal.2021.02.003] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2020] [Revised: 01/29/2021] [Accepted: 02/01/2021] [Indexed: 12/13/2022]
Abstract
Glaucoma is an optic neuropathy characterized by well-defined optic disc morphological changes (i.e., cup enlargement, neuroretinal border thinning, and notching, papillary vessel modifications) consequent to retinal ganglion cell loss, axonal degeneration, and lamina cribrosa remodeling. These modifications tend to be progressive and are the main cause of functional damage in glaucoma. Despite the latest findings about the pathophysiology of the disease, the exact trigger mechanisms and the mechanism of degeneration of retinal ganglion cells and their axons have not been completely elucidated. Neuroinflammation may play a role in both the development and the progression of the disease as a result of its effects on retinal environment and retinal ganglion cells. We summarize the latest findings about neuroinflammation in glaucoma and examine the connection between risk factors, neuroinflammation, and retinal ganglion cell degeneration.
Collapse
Affiliation(s)
- Luciano Quaranta
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy.
| | - Carlo Bruttini
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
| | - Eleonora Micheletti
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
| | - Anastasios G P Konstas
- 1st and 3rd University Departments of Ophthalmology, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | | | | | - Andreas Katsanos
- Department of Ophthalmology, University of Ioannina, Ioannina, Greece
| | | | - Giovanni De Angelis
- Department of Surgical & Clinical, Diagnostic and Pediatric Sciences, Section of Ophthalmology, University of Pavia - IRCCS Fondazione Policlinico San Matteo, Pavia, Italy
| | | |
Collapse
|
8
|
Ren LM, Zhang YH. Houttuynia cordata Thunb rescues retinal ganglion cells through inhibiting microglia activation in a rat model of retinal ischemia-reperfusion. Int J Ophthalmol 2020; 13:1880-1886. [PMID: 33344185 DOI: 10.18240/ijo.2020.12.06] [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: 02/15/2020] [Accepted: 09/08/2020] [Indexed: 11/23/2022] Open
Abstract
AIM To determine whether Houttuynia cordata Thunb (HCT) can increase the survival of the retinal ganglion cells (RGCs) and inhibit microglia activation following retinal ischemia-reperfusion (RIR) injury. METHODS Rat model of RIR was induced by transient elevation of the intraocular pressure (IOP). HCT was orally administered for 2d before the performance of retinal RIR model and once a day for the next 14d. After 14d of RIR injury, the rats were sacrificed for further analysis. Survival RGCs were stained with haematoxylin and eosin (H&E). Apoptosis of RGCs was detected by TUNEL staining. Retinal function was examined by flash-electroretinography (F-ERG). Retinal microglia were labeled using Iba-1, one specific marker for microglia. The mRNA expression levels of inducible nitric oxide synthase (iNOS), tumor necrosis factor alpha (TNF-α), and interleukin 1 beta (IL-1β) were assessed by quantitative real time reverse transcription polymerase chain reaction (qRT-PCR). RESULTS Systemic HCT treatment significantly reduced RGCs death by H&E staining and exhibited an anti-apoptotic effect as assessed by TUNEL staining at day 14 after RIR injury. HCT greatly improved the retinal function as examined by F-ERG. The number of activated microglia significantly increased after RIR injury, which was significantly attenuated by HCT treatment. Besides, RIR injury induced a strong upregulation of pro-inflammatory genes TNF-α, iNOS and IL-1β mRNAs at day 14 post injury, which was suppressed by HCT. CONCLUSION Neuroprotective effects of HCT encourage the survival of RGCs through inhibiting microglia activation due to RIR injury. Together these results support the use of HCT as promising therapy for the ischemic events of the retina diseases.
Collapse
Affiliation(s)
- Le-Meng Ren
- The First Clinical Medical College, Lanzhou University, Lanzhou 730000, Gansu Province, China
| | - Ying-Hui Zhang
- Medical Record Room, the Second Hospital of Shandong University, Shandong University, Jinan 250033, Shandong Province, China
| |
Collapse
|
9
|
Zhao Z, Yu X, Yang X, Zhang J, Zhang D, Sun N, Fan Z. Elevated intraocular pressure causes cellular and molecular retinal injuries, advocating a more moderate intraocular pressure setting during phacoemulsification surgery. Int Ophthalmol 2020; 40:3323-3336. [PMID: 32725401 DOI: 10.1007/s10792-020-01519-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Accepted: 07/17/2020] [Indexed: 01/04/2023]
Abstract
PURPOSE To evaluate the cellular and molecular retinal injuries induced by various intraocular pressure (IOP) settings in a mouse model of acute ocular hypertension (AOH), and to advise using a more moderate target IOP during phacoemulsification (phaco) surgery. METHODS A mouse model of AOH that mimics a transient IOP elevation during phacoemulsification cataract surgery was established. Six groups with various settings of target IOP were included. Retinal tissues were assessed with terminal deoxynucleotidyl transferase-mediated 2'-deoxyuridine 5'-triphosphate nick end-labeling (TUNEL) staining for neuron loss, immunofluorescence with Iba1 for microglia activation, and quantitative real-time polymerase chain reaction analysis with tight junction proteins (claudin-3 and claudin-5) or classic inflammation markers (IL-1β and eNOS) for impairment of the blood-retinal barrier (BRB) and inflammatory injury. RESULTS Compared with those in the 45-mmHg IOP group, significantly increased number of neurons loss and increased microglia activation were observed in 90-mmHg IOP group. In addition, the expression of claudin-3 and claudin-5 was significantly decreased, while the expression of IL1-β and eNOS was up-regulated, indicating impairment of the BRB and inflammatory injury in the retina. Furthermore, these findings of neuron loss, microglia activation, and inflammation in the 90-mmHg groups were exacerbated when an IOP-induced retinal injury was established 5 days earlier, while those in the 45-mmHg groups remained almost unchanged. CONCLUSIONS In conclusion, these results showed that a relatively commonly used high IOP setting (90 mmHg) could induce significantly more serious retinal injury. An IOP setting around 45 mmHg is relatively safe and might be recommended in phaco surgery, especially in patients with advanced glaucoma, previous acute angle closure crisis, or other diseases with fragile retina and optic nerve.
Collapse
Affiliation(s)
- Zhenni Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China
| | - Xiaowei Yu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China
| | - Xue Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China
| | - Jiamin Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China
| | - Dandan Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China
| | - Nannan Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China.
| | - Zhigang Fan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Jinsui Road NO.7, Guangzhou, 510060, Guangdong, China.
| |
Collapse
|
10
|
Cao K, Ishida T, Fang Y, Shinohara K, Li X, Nagaoka N, Ohno-Matsui K, Yoshida T. Protection of the Retinal Ganglion Cells: Intravitreal Injection of Resveratrol in Mouse Model of Ocular Hypertension. Invest Ophthalmol Vis Sci 2020; 61:13. [PMID: 32176263 PMCID: PMC7401839 DOI: 10.1167/iovs.61.3.13] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Purpose To investigate the efficacy of intravitreal administration of resveratrol (RSV) in a microbead-induced high intraocular pressure (IOP) murine model for glaucoma. Methods Experiments were performed using adult C57BL/6JJcl mice. Polystyrene microbeads were injected into the anterior chamber to induce IOP elevation. Retinal flat-mounts and sections were assessed by immunohistochemistry to detect the expression of reactive oxygen species and acetyl-p53 in retinal ganglion cells (RGCs), brain-derived neurotrophic factor (BDNF) in Müller glial cells (MGCs), and the receptor tropomyosin receptor kinase B (TrkB) in RGCs. Light cycler real-time PCR was also used for confirming gene expression of BDNF in primary cultured MGCs exposed to RSV. Results Microbeads induced high IOP followed by RGC death and axon loss. Administration of RSV rescued RGCs via decreased reactive oxygen species generation and acetyl-p53 expression in RGCs and upregulated BDNF in MGCs and TrkB expression in RGCs, which exhibited a strong cytoprotective action against cell death through multiple pathways under high IOP. Conclusions Our data suggest that administration of RSV may delay the progress of visual dysfunction during glaucoma and may therefore have therapeutic potential.
Collapse
|
11
|
Qin Z, He S, Yang C, Yung JSY, Chen C, Leung CKS, Liu K, Qu JY. Adaptive optics two-photon microscopy enables near-diffraction-limited and functional retinal imaging in vivo. LIGHT, SCIENCE & APPLICATIONS 2020; 9:79. [PMID: 32411364 PMCID: PMC7203252 DOI: 10.1038/s41377-020-0317-9] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2020] [Revised: 04/11/2020] [Accepted: 04/15/2020] [Indexed: 05/08/2023]
Abstract
In vivo fundus imaging offers non-invasive access to neuron structures and biochemical processes in the retina. However, optical aberrations of the eye degrade the imaging resolution and prevent visualization of subcellular retinal structures. We developed an adaptive optics two-photon excitation fluorescence microscopy (AO-TPEFM) system to correct ocular aberrations based on a nonlinear fluorescent guide star and achieved subcellular resolution for in vivo fluorescence imaging of the mouse retina. With accurate wavefront sensing and rapid aberration correction, AO-TPEFM permits structural and functional imaging of the mouse retina with submicron resolution. Specifically, simultaneous functional calcium imaging of neuronal somas and dendrites was demonstrated. Moreover, the time-lapse morphological alteration and dynamics of microglia were characterized in a mouse model of retinal disorder. In addition, precise laser axotomy was achieved, and degeneration of retinal nerve fibres was studied. This high-resolution AO-TPEFM is a promising tool for non-invasive retinal imaging and can facilitate the understanding of a variety of eye diseases as well as neurodegenerative disorders in the central nervous system.
Collapse
Affiliation(s)
- Zhongya Qin
- Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Sicong He
- Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Chao Yang
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Jasmine Sum-Yee Yung
- Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong, China
| | - Congping Chen
- Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | | | - Kai Liu
- Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- Center of Systems Biology and Human Health, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| | - Jianan Y. Qu
- Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- State Key Laboratory of Molecular Neuroscience, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
- Center of Systems Biology and Human Health, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China
| |
Collapse
|
12
|
Time course of bilateral microglial activation in a mouse model of laser-induced glaucoma. Sci Rep 2020; 10:4890. [PMID: 32184450 PMCID: PMC7078298 DOI: 10.1038/s41598-020-61848-9] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 03/03/2020] [Indexed: 12/31/2022] Open
Abstract
Microglial activation is associated with glaucoma. In the model of unilateral laser-induced ocular hypertension (OHT), the time point at which the inflammatory process peaks remains unknown. Different time points (1, 3, 5, 8, and 15 d) were compared to analyze signs of microglial activation both in OHT and contralateral eyes. In both eyes, microglial activation was detected in all retinal layers at all time points analyzed, including: i) increase in the cell number in the outer segment photoreceptor layer and plexiform layers (only in OHT eyes) from 3 d onward; ii) increase in soma size from 1 d onward; iii) retraction of the processes from 1 d in OHT eyes and 3 d in contralateral eyes; iv) increase in the area of the retina occupied by Iba-1+ cells in the nerve fiber layer/ganglion cell layer from 1 d onward; v) increase in the number of vertical processes from 1 d in contralateral eyes and 3 d in OHT eyes. In OHT eyes at 24 h and 15 d, most Iba-1+ cells were P2RY12+ and were down-regulated at 3 and 5 d. In both eyes, microglial activation was stronger at 3 and 5 d (inflammation peaked in this model). These time points could be useful to identify factors implicated in the inflammatory process.
Collapse
|
13
|
Zhang X, Zhang R, Chen J, Wu J. Neuroprotective effects of DAAO are mediated via the ERK1/2 signaling pathway in a glaucomatous animal model. Exp Eye Res 2020; 190:107892. [DOI: 10.1016/j.exer.2019.107892] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2019] [Revised: 10/31/2019] [Accepted: 12/03/2019] [Indexed: 01/06/2023]
|
14
|
Gardiner SK, Cull G, Fortune B, Wang L. Increased Optic Nerve Head Capillary Blood Flow in Early Primary Open-Angle Glaucoma. Invest Ophthalmol Vis Sci 2019; 60:3110-3118. [PMID: 31323681 PMCID: PMC6645706 DOI: 10.1167/iovs.19-27389] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Blood flow in the optic nerve head (ONH) is known to be reduced in eyes with advanced glaucoma. However, experimental results from non-human primates suggest an initial increase in ONH blood flow at the earliest stages of damage. This study assesses flow and pulsatile hemodynamics across a range of severities to test the hypothesis that this also occurs in human glaucoma. Methods Laser speckle flowgraphy was used to measure average mean blur rate (MBRave) within ONH tissue (a correlate of capillary blood flow) and the pulsatile waveform in 93 eyes with functional loss and 74 glaucoma suspect/fellow eyes without functional loss. These were compared against results from 92 healthy control eyes. Parameters produced by the instrument's software were age-corrected, then compared between groups using generalized estimating equation models. Results The mean MBRave in the control eyes was 12.5 units. In glaucoma suspect/fellow eyes, the mean was 16.4 units, higher with P < 0.0001. In eyes with functional loss, the mean was 13.8 units, lower than eyes without functional loss with P < 0.0001, although still higher than control eyes with P = 0.0096. Analysis of the pulsatile waveform suggested that the deceleration in flow as it approaches its maximum across the cardiac cycle was delayed in glaucoma. Conclusions Blood flow within ONH capillaries was higher in glaucoma suspect eyes than in healthy controls. It was less elevated in eyes that had developed functional loss. The mechanisms causing these changes and their relation to concurrent changes in pulsatile hemodynamics remain under investigation.
Collapse
Affiliation(s)
- Stuart K Gardiner
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Grant Cull
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Brad Fortune
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| | - Lin Wang
- Devers Eye Institute, Legacy Health, Portland, Oregon, United States
| |
Collapse
|
15
|
Fernández-Albarral JA, Ramírez AI, de Hoz R, López-Villarín N, Salobrar-García E, López-Cuenca I, Licastro E, Inarejos-García AM, Almodóvar P, Pinazo-Durán MD, Ramírez JM, Salazar JJ. Neuroprotective and Anti-Inflammatory Effects of a Hydrophilic Saffron Extract in a Model of Glaucoma. Int J Mol Sci 2019; 20:E4110. [PMID: 31443568 PMCID: PMC6747458 DOI: 10.3390/ijms20174110] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Revised: 08/19/2019] [Accepted: 08/20/2019] [Indexed: 12/11/2022] Open
Abstract
Glaucoma is a neurodegenerative disease characterized by the loss of retinal ganglion cells (RGCs). An increase in the intraocular pressure is the principal risk factor for such loss, but controlling this pressure does not always prevent glaucomatous damage. Activation of immune cells resident in the retina (microglia) may contribute to RGC death. Thus, a substance with anti-inflammatory activity may protect against RGC degeneration. This study investigated the neuroprotective and anti-inflammatory effects of a hydrophilic saffron extract standardized to 3% crocin content in a mouse model of unilateral, laser-induced ocular hypertension (OHT). Treatment with saffron extract decreased microglion numbers and morphological signs of their activation, including soma size and process retraction, both in OHT and in contralateral eyes. Saffron extract treatment also partially reversed OHT-induced down-regulation of P2RY12. In addition, the extract prevented retinal ganglion cell death in OHT eyes. Oral administration of saffron extract was able to decrease the neuroinflammation associated with increased intraocular pressure, preventing retinal ganglion cell death. Our findings indicate that saffron extract may exert a protective effect in glaucomatous pathology.
Collapse
Affiliation(s)
| | - Ana I Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
- Departamento de Inmunología, Oftalmología y ORL, Facultad de Óptica y Optometría, UCM, 28037 Madrid, Spain
| | - Rosa de Hoz
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
- Departamento de Inmunología, Oftalmología y ORL, Facultad de Óptica y Optometría, UCM, 28037 Madrid, Spain
| | - Nerea López-Villarín
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
| | - Elena Salobrar-García
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
| | - Inés López-Cuenca
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
| | - Ester Licastro
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain
| | | | - Paula Almodóvar
- Pharmactive Biotech Products, SL. Parque Científico de Madrid, Faraday 7, 28049 Madrid, Spain
| | - Maria D Pinazo-Durán
- Unidad de Investigación Oftalmológica Santiago Grisolia, Universidad de Valencia, 46017 Valencia, Spain
| | - José M Ramírez
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain.
- Departamento de Inmunología, Oftalmología y ORL, Facultad de Medicina, UCM, 28040 Madrid, Spain.
| | - Juan J Salazar
- Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, UCM, 28040 Madrid, Spain.
- Departamento de Inmunología, Oftalmología y ORL, Facultad de Óptica y Optometría, UCM, 28037 Madrid, Spain.
| |
Collapse
|
16
|
Transfer of the Experimental Autoimmune Glaucoma Model from Rats to Mice-New Options to Study Glaucoma Disease. Int J Mol Sci 2019; 20:ijms20102563. [PMID: 31137749 PMCID: PMC6566658 DOI: 10.3390/ijms20102563] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 05/13/2019] [Accepted: 05/21/2019] [Indexed: 12/25/2022] Open
Abstract
Studies have suggested an involvement of the immune system in glaucoma. Hence, a rat experimental autoimmune glaucoma model (EAG) was developed to investigate the role of the immune response. Here, we transferred this model into mice. Either 0.8 mg/mL of the optic nerve antigen homogenate (ONA; ONA 0.8) or 1.0 mg/mL ONA (ONA 1.0) were injected in 129/Sv mice. Controls received sodium chloride. Before and 6 weeks after immunization, the intraocular pressure (IOP) was measured. At 6 weeks, retinal neurons, glia cells, and synapses were analyzed via immunohistology and quantitative real-time PCR (RT-qPCR). Additionally, optic nerves were examined. The IOP stayed in the normal physiological range throughout the study (p > 0.05). A significant reduction of retinal ganglion cells (RGCs) was noted in both immunized groups (p < 0.001). Remodeling of glutamatergic and GABAergic synapses was seen in ONA 1.0 retinas. Furthermore, both ONA groups revealed optic nerve degeneration and macrogliosis (all: p < 0.001). An increase of activated microglia was noted in ONA retinas and optic nerves (p < 0.05). Both ONA concentrations led to RGC loss and optic nerve degeneration. Therefore, the EAG model was successfully transferred from rats to mice. In further studies, transgenic knockout mice can be used to investigate the pathomechanisms of glaucoma more precisely.
Collapse
|
17
|
Kuehn S, Meißner W, Grotegut P, Theiss C, Dick HB, Joachim SC. Intravitreal S100B Injection Leads to Progressive Glaucoma Like Damage in Retina and Optic Nerve. Front Cell Neurosci 2018; 12:312. [PMID: 30319357 PMCID: PMC6169322 DOI: 10.3389/fncel.2018.00312] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/28/2018] [Indexed: 12/15/2022] Open
Abstract
The glial protein S100B, which belongs to a calcium binding protein family, is up-regulated in neurological diseases, like multiple sclerosis or glaucoma. In previous studies, S100B immunization led to retinal ganglion cell (RGC) loss in an experimental autoimmune glaucoma (EAG) model. Now, the direct degenerative impact of S100B on the retina and optic nerve was evaluated. Therefore, 2 μl of S100B was intravitreally injected in two concentrations (0.2 and 0.5 μg/μl). At day 3, 14 and 21, retinal neurons, such as RGCs, amacrine and bipolar cells, as well as apoptotic mechanisms were analyzed. Furthermore, neurofilaments, myelin fibers and axons of optic nerves were evaluated. In addition, retinal function and immunoglobulin G (IgG) level in the serum were measured. At day 3, RGCs were unaffected in the S100B groups, when compared to the PBS group. Later, at days 14 and 21, the RGC number as well as the β-III tubulin protein level was reduced in the S100B groups. Only at day 14, active apoptotic mechanisms were noted. The number of amacrine cells was first affected at day 21, while the bipolar cell amount remained comparable to the PBS group. Also, the optic nerve neurofilament structure was damaged from day 3 on. At day 14, numerous swollen axons were observed. The intraocular injection of S100B is a new model for a glaucoma like degeneration. Although the application site was the eye, the optic nerve degenerated first, already at day 3. From day 14 on, retinal damage and loss of function was noted. The RGCs in the middle part of the retina were first affected. At day 21, the damage expanded and RGCs had degenerated in all areas of the retina as well as amacrine cells. Furthermore, elevated IgG levels in the serum were measured at day 21, which could be a sign of a late and S100B independet immune response. In summary, S100B had a direct destroying impact on the axons of the optic nerve. The damage of the retinal cell bodies seems to be a consequence of this axon loss.
Collapse
Affiliation(s)
- Sandra Kuehn
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Wilhelm Meißner
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Pia Grotegut
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Carsten Theiss
- Department of Cytology, Institute of Anatomy, Ruhr-University Bochum, Bochum, Germany
| | - H Burkhard Dick
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research Institute, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| |
Collapse
|
18
|
Bilateral early activation of retinal microglial cells in a mouse model of unilateral laser-induced experimental ocular hypertension. Exp Eye Res 2018. [PMID: 29526796 DOI: 10.1016/j.exer.2018.03.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
The immune system plays an important role in glaucomatous neurodegeneration. Retinal microglial reactivation associated with ganglion cell loss could reportedly contribute to the glaucoma progression. Recently we have described signs of microglia activation both in contralateral and ocular hypertension (OHT) eyes involving all retinal layers 15 days after OHT laser induction in mice. However, no works available have analyzed the microglial activation at earliest time points after OHT induction (24 h) in this experimental model. Thus, we seek to describe and quantify signs of microglia activation and differences depending on the retinal layer, 24 h after unilateral laser-induced OHT. Two groups of adult Swiss mice were used: age-matched control (naïve) and lasered. In the lasered animals, OHT eyes as well as contralateral eyes were analyzed. Retinal whole-mounts were immunostained with antibodies against Iba-1 and MHC-II. We quantified the number of microglial cells in the photoreceptor layer (OS), outer plexiform layer (OPL), and inner plexiform layer (IPL); the number of microglial vertical processes connecting the OPL and OS; the area of the retina occupied by Iba-1+ cells (Iba1-RA) in the nerve fiber layer-ganglion cell layer (NFL-GCL), the total arbor area of microglial cells in the OPL and IPL and; Iba-1+ cell body area in the OPL, IPL and NFL-GCL. In contralateral and OHT eyes the morphological features of Iba-1+ cell activation were: migration, enlargement of the cell body, higher degree of branching and reorientation of the processes, radial disposition of the soma and processes toward adjacent microglial plexuses, and presence of amoeboid cells acting as macrophages. These signs were more pronounced in OHT eyes. Most of Iba-1+ cells did not express MHC-II; rather, only dendritic and rounded cells expressed it. In comparison with naïve eyes, in OHT eyes and contralateral eyes no significant differences were found in the microglial cell number; but there was a significant increase in Iba1-RA. The total arbor area of microglial cells was significantly decreased in: i) OHT eyes with respect contralateral eyes and naïve-eyes in IPL; ii) OHT eyes with respect to naïve eyes in OPL. The number of microglial vertical processes connecting the OPL and OS were significantly increased in contralateral eyes compared with naïve-eyes and OHT eyes. In OPL, IPL and NFL-GCL, the cell body area of Iba-1+ cells was significantly greater in OHT eyes than in naïve and contralateral eyes, and greater in contralateral eyes than in naïve eyes. A non-proliferative microglial reactivation was detected both in contralateral eyes and in OHT eyes in an early time after unilateral laser-induced OHT (24 h). This fast microglial activation, which involves the contralateral eye, could be mediated by the immune system.
Collapse
|
19
|
Nadal-Nicolás FM, Jiménez-López M, Salinas-Navarro M, Sobrado-Calvo P, Vidal-Sanz M, Agudo-Barriuso M. Microglial dynamics after axotomy-induced retinal ganglion cell death. J Neuroinflammation 2017; 14:218. [PMID: 29121969 PMCID: PMC5679427 DOI: 10.1186/s12974-017-0982-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 10/16/2017] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND Microglial cells (MCs) are the sentries of the central nervous system. In health, they are known as surveying MCs because they examine the tissue to maintain the homeostasis. In disease, they activate and, among other functions, become phagocytic to clean the cellular debris. In this work, we have studied the behavior of rat retinal MCs in two models of unilateral complete intraorbital optic nerve axotomy which elicit a different time course of retinal ganglion cell (RGC) loss. METHODS Albino Sprague-Dawley rats were divided into these groups: (a) intact (no surgery), (b) fluorogold (FG) tracing from the superior colliculi, and (c) FG tracing + crush or transection of the left optic nerve. The retinas were dissected from 2 days to 2 months after the lesions (n = 4-12 group/lesion and time point) and then were subjected to Brn3a and Iba1 double immunodetection. In each intact retina, the total number of Brn3a+RGCs and Iba+MCs was quantified. In each traced retina (b and c groups), FG-traced RGCs and phagocytic microglial cells (PMCs, FG+Iba+) were also quantified. Topographical distribution was assessed by neighbor maps. RESULTS In intact retinas, surveying MCs are homogenously distributed in the ganglion cell layer and the inner plexiform layer. Independently of the axotomy model, RGC death occurs in two phases, one quick and one protracted, and there is a lineal and topographical correlation between the appearance of PMCs and the loss of traced RGCs. Furthermore, the clearance of FG+RGCs by PMCs occurs 3 days after the actual loss of Brn3a expression that marks RGC death. In addition, almost 50% of MCs from the inner plexiform layer migrate to the ganglion cell layer during the quick phase of RGC loss, returning to the inner plexiform layer during the slow degeneration phase. Finally, in contrast to what happens in mice, in rats, there is no microglial phagocytosis in the contralateral uninjured retina. CONCLUSIONS Axotomy-induced RGC death occurs earlier than RGC clearance and there is an inverse correlation between RGC loss and PMC appearance, both numerically and topographically, suggesting that phagocytosis occurs as a direct response to RGC death rather than to axonal damage.
Collapse
Affiliation(s)
- Francisco M Nadal-Nicolás
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain.
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
- Present address: Retinal Neurophysiology Section, National Eye Institute, National Institutes of Health, Bethesda, MD, 20892, USA.
| | - Manuel Jiménez-López
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain
| | - Manuel Salinas-Navarro
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain
| | - Paloma Sobrado-Calvo
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain
| | - Manuel Vidal-Sanz
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain
| | - Marta Agudo-Barriuso
- Grupo de Oftalmología Experimental, Instituto Murciano de Investigación Biosanitaria-Virgen de la Arrixaca, Edificio LAIB Planta 5ª, Carretera Buenavista s/n, 30120, El Palmar, Murcia, Spain.
- Departamento de Oftalmología, Facultad de Medicina, Universidad de Murcia, Murcia, Spain.
| |
Collapse
|
20
|
Dose-dependent mortality involving convulsions due to subarachnoid Urografin® injection in rats. Leg Med (Tokyo) 2017; 29:29-33. [DOI: 10.1016/j.legalmed.2017.09.004] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 01/17/2017] [Accepted: 09/30/2017] [Indexed: 01/23/2023]
|
21
|
Wang JW, Liu YM, Zhao XF, Zhang H. Gastrodin protects retinal ganglion cells through inhibiting microglial-mediated neuroinflammation in an acute ocular hypertension model. Int J Ophthalmol 2017; 10:1483-1489. [PMID: 29062764 DOI: 10.18240/ijo.2017.10.01] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2017] [Accepted: 07/10/2017] [Indexed: 12/20/2022] Open
Abstract
AIM To investigate the neuroprotective effect of gastrodin on retinal ganglion cells (RGCs) in an acute ocular hypertension (AOH) rat model and to identify its possible mechanism. METHODS AOH rat model was performed in a randomly selected eye by anterior chamber perfusion and either received an intraperitoneal injection with various concentrations of gastrodin or normal saline. After 2wk, the rats were sacrificed. FluoroGold was used to label survival RGCs. Immunostaining with anti-Iba1 in the retinal flat mounts to calculate the microglia density in the ganglion cell layer (GCL). Changes in microglial cytokines, tumour necrosis factor-alpha (TNF-α) and inducible NO synthase (iNOS) were examined with Western blot and reverse transcription-quantitative polymerase chain reaction. Expression levels of total and phosphorylated p38 mitogen activated protein kinase (MAPK) were determined by Western blot. RESULTS Results showed that AOH induced significant loss of RGCs and severe microglia activation in the GCL. Besides, AOH increased the phosphorylation of p38 MAPK and promoted the release of microglial cytokines in the retinas. Intraperitoneal injection with dose-dependent gastrodin significantly reduced the loss of RGCs and inhibited retinal microglia activation, accompanied with the decreased expression levels of microglial cytokines and p38 MAPK phosphorylation. CONCLUSION Gastrodin exerts a neuroprotective effect on RGCs in an acute glaucoma animal model via inhibiting microglia activation and microglial-mediated neuroinflammation. The finding demonstrates the potential application of gastrodin in the neuroprotective therapy of acute glaucoma and other retinal neurodegenerative diseases characterized by microglia activation and RGCs death.
Collapse
Affiliation(s)
- Jia-Wei Wang
- Eye Center of Shandong University, the Second Hospital of Shandong University, Shandong University, Jinan 250033, Shandong Province, China.,Zhongshan Ophthalmic Center, State Key Laboratory of Ophthalmology, Sun Yat-Sen University, Guangzhou 510060, Guangdong Province, China
| | - Yao-Ming Liu
- Zhongshan Ophthalmic Center, State Key Laboratory of Ophthalmology, Sun Yat-Sen University, Guangzhou 510060, Guangdong Province, China
| | - Xiao-Fei Zhao
- Eye Center of Shandong University, the Second Hospital of Shandong University, Shandong University, Jinan 250033, Shandong Province, China
| | - Han Zhang
- Eye Center of Shandong University, the Second Hospital of Shandong University, Shandong University, Jinan 250033, Shandong Province, China
| |
Collapse
|
22
|
Hanlon KS, Chadderton N, Palfi A, Blanco Fernandez A, Humphries P, Kenna PF, Millington-Ward S, Farrar GJ. A Novel Retinal Ganglion Cell Promoter for Utility in AAV Vectors. Front Neurosci 2017; 11:521. [PMID: 28983234 PMCID: PMC5613148 DOI: 10.3389/fnins.2017.00521] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Accepted: 09/04/2017] [Indexed: 12/13/2022] Open
Abstract
Significant advances in gene therapy have enabled exploration of therapies for inherited retinal disorders, many of which are in preclinical development or clinical evaluation. Gene therapy for retinal conditions has led the way in this growing field. The loss of retinal ganglion cells (RGCs) is a hallmark of a number of retinal disorders. As the field matures innovations that aid in refining therapies and optimizing efficacy are in demand. Gene therapies under development for RGC-related disorders, when delivered with recombinant adeno associated vectors (AAV), have typically been expressed from ubiquitous promoter sequences. Here we describe how a novel promoter from the murine Nefh gene was selected to drive transgene expression in RGCs. The Nefh promoter, in an AAV2/2 vector, was shown to drive preferential EGFP expression in murine RGCs in vivo following intravitreal injection. In contrast, EGFP expression from a CMV promoter was observed not only in RGCs, but throughout the inner nuclear layer and in amacrine cells located within the ganglion cell layer (GCL). Of note, the Nefh promoter sequence is sufficiently compact to be readily accommodated in AAV vectors, where transgene size represents a significant constraint. Moreover, this promoter should in principle provide a more targeted and potentially safer alternative for RGC-directed gene therapies.
Collapse
Affiliation(s)
- Killian S Hanlon
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| | - Naomi Chadderton
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| | - Arpad Palfi
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| | | | - Peter Humphries
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| | - Paul F Kenna
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland.,Research Foundation, Royal Victoria Eye and Ear HospitalDublin, Ireland
| | - Sophia Millington-Ward
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| | - G Jane Farrar
- School of Genetics and Microbiology, Smurfit Institute of Genetics, Trinity College DublinDublin, Ireland
| |
Collapse
|
23
|
Kuehn S, Hurst J, Jashari A, Ahrens K, Tsai T, Wunderlich IM, Dick HB, Joachim SC, Schnichels S. The novel induction of retinal ganglion cell apoptosis in porcine organ culture by NMDA - an opportunity for the replacement of animals in experiments. Altern Lab Anim 2017; 44:557-568. [PMID: 28094536 DOI: 10.1177/026119291604400608] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Some of the advantages of retina organ culture models include their efficient and easy handling and the ability to standardise relevant parameters. Additionally, when porcine eyes are obtained from the food industry, no animals are killed solely for research purposes. To induce retinal degeneration, a commonly used toxic substance, N-methyl-D-aspartate (NMDA), was applied to the cultures. To this end, organotypic cultures of porcine retinas were cultured and treated with different doses of NMDA (0 [control], 50, 100 and 200μM) on day 2 for 48 hours. On day 7, the retinas were cryo-conserved for histological, Western blot and quantitative rt-PCR (qrt-PCR) analyses. NMDA treatment was found to significantly increase retinal ganglion cell (RGC) apoptosis in all the treated groups, without a profound RGC loss. In addition, the intrinsic apoptotic pathway was activated in the 50μM and 100μM NMDA groups, whereas induced nitric oxide synthase (iNOS) expression was increased in the 200μM group. A slight microglial response was detectable, especially in the 100μM group. NMDA treatment induced apoptosis, oxidative stress and a slight microglia activation. All these effects mimic a chronic slow progressive disease that especially affects RGCs, such as glaucoma. A particular advantage of this model is that mediators that can interact in the very early stages of the onset of RGC death, can be easily detected and potential therapies can be tested.
Collapse
Affiliation(s)
- Sandra Kuehn
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Jose Hurst
- University Eye Hospital Tübingen, Centre for Ophthalmology, Tübingen, Germany
| | - Adelina Jashari
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Kathrin Ahrens
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Teresa Tsai
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Ilan M Wunderlich
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - H Burkhard Dick
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Stephanie C Joachim
- Experimental Eye Research, University Eye Hospital, Ruhr-University Bochum, Bochum, Germany
| | - Sven Schnichels
- University Eye Hospital Tübingen, Centre for Ophthalmology, Tübingen, Germany
| |
Collapse
|
24
|
Davis BM, Salinas-Navarro M, Cordeiro MF, Moons L, De Groef L. Characterizing microglia activation: a spatial statistics approach to maximize information extraction. Sci Rep 2017; 7:1576. [PMID: 28484229 PMCID: PMC5431479 DOI: 10.1038/s41598-017-01747-8] [Citation(s) in RCA: 206] [Impact Index Per Article: 29.4] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 03/30/2017] [Indexed: 01/12/2023] Open
Abstract
Microglia play an important role in the pathology of CNS disorders, however, there remains significant uncertainty about the neuroprotective/degenerative role of these cells due to a lack of techniques to adequately assess their complex behaviour in response to injury. Advancing microscopy techniques, transgenic lines and well-characterized molecular markers, have made histological assessment of microglia populations more accessible. However, there is a distinct lack of tools to adequately extract information from these images to fully characterise microglia behaviour. This, combined with growing economic pressures and the ethical need to minimise the use of laboratory animals, led us to develop tools to maximise the amount of information obtained. This study describes a novel approach, combining image analysis with spatial statistical techniques. In addition to monitoring morphological parameters and global changes in microglia density, nearest neighbour distance, and regularity index, we used cluster analyses based on changes in soma size and roundness to yield novel insights into the behaviour of different microglia phenotypes in a murine optic nerve injury model. These methods should be considered a generic tool to quantitatively assess microglia activation, to profile phenotypic changes into microglia subpopulations, and to map spatial distributions in virtually every CNS region and disease state.
Collapse
Affiliation(s)
- Benjamin M Davis
- Glaucoma and Retinal Neurodegenerative Disease Research Group, Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, United Kingdom
| | - Manual Salinas-Navarro
- Neural Circuit Development and Regeneration Research Group, Department of Biology, University of Leuven, Naamsestraat 61 box 2464, 3000, Leuven, Belgium
| | - M Francesca Cordeiro
- Glaucoma and Retinal Neurodegenerative Disease Research Group, Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, United Kingdom.,Western Eye Hospital, Imperial College Healthcare NHS Trust, 171 Marylebone Road, London, NW1 5QH, United Kingdom
| | - Lieve Moons
- Neural Circuit Development and Regeneration Research Group, Department of Biology, University of Leuven, Naamsestraat 61 box 2464, 3000, Leuven, Belgium
| | - Lies De Groef
- Glaucoma and Retinal Neurodegenerative Disease Research Group, Institute of Ophthalmology, University College London, 11-43 Bath Street, London, EC1V 9EL, United Kingdom. .,Neural Circuit Development and Regeneration Research Group, Department of Biology, University of Leuven, Naamsestraat 61 box 2464, 3000, Leuven, Belgium.
| |
Collapse
|
25
|
Yang X, Huo F, Liu B, Liu J, Chen T, Li J, Zhu Z, Lv B. Crocin Inhibits Oxidative Stress and Pro-inflammatory Response of Microglial Cells Associated with Diabetic Retinopathy Through the Activation of PI3K/Akt Signaling Pathway. J Mol Neurosci 2017; 61:581-589. [PMID: 28238066 DOI: 10.1007/s12031-017-0899-8] [Citation(s) in RCA: 84] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Accepted: 02/10/2017] [Indexed: 01/24/2023]
Abstract
Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus that is closely associated with the degeneration and loss of retinal ganglion cells (RGCs) caused by diabetic microangiopathy and subsequent oxidative stress and an inflammatory response. Microglial cells are classed as neurogliocytes and play a significant role in neurodegenerative diseases. Over-activated microglial cells may cause neurotoxicity and induce the death and apoptosis of RGCs. Crocin is one of the two most pharmacologically bioactive constituents in saffron. In the present study, we focused on the role of microglial cells in DR, suggesting that DR may cause the over-activation of microglial cells and induce oxidative stress and the release of pro-inflammatory factors. Microglial cells BV-2 and N9 were cultured, and high-glucose (HG) and free fatty acid (FFA) were used to simulate diabetes. The results showed that HG-FFA co-treatment caused the up-regulated expression of CD11b and Iba-1, indicating that BV-2 and N9 cells were over-activated. Moreover, oxidative stress markers and pro-inflammatory factors were significantly enhanced by HG-FFA treatment. We found that crocin prevented the oxidative stress and pro-inflammatory response induced by HG-FFA co-treatment. Moreover, using the PI3K/Akt inhibitor LY294002, we revealed that PI3K/Akt signaling plays a significant role in blocking oxidative stress, suppressing the pro-inflammatory response, and maintaining the neuroprotective effects of crocin. In total, these results provide a new insight into DR and DR-induced oxidative stress and the inflammatory response, which provide a potential therapeutic target for neuronal damage, vision loss, and other DR-induced complications.
Collapse
Affiliation(s)
- Xinguang Yang
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Guangren Hospital Affiliated to School of Medicine of Xi'an Jiaotong University, No. 21 Jiefang Road, Xi'an, Shaanxi, 710004, People's Republic of China
| | - Fuquan Huo
- Department of Physiology and Pathophysiology, Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education, School of Medicine, Xi'an Jiaotong University, Xi'an, Shaanxi, 710061, China
| | - Bei Liu
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Guangren Hospital Affiliated to School of Medicine of Xi'an Jiaotong University, No. 21 Jiefang Road, Xi'an, Shaanxi, 710004, People's Republic of China
| | - Jing Liu
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Guangren Hospital Affiliated to School of Medicine of Xi'an Jiaotong University, No. 21 Jiefang Road, Xi'an, Shaanxi, 710004, People's Republic of China
| | - Tao Chen
- Department of Anatomy, Histology and Embryology and K. K. Leung Brain Research Centre, The Fourth Military Medical University, Xi'an, Shaanxi, 710032, People's Republic of China
| | - Junping Li
- Department of Anatomy, Histology and Embryology, Ningxia Medical University, Yinchuan, Ningxia, 750004, People's Republic of China
| | - Zhongqiao Zhu
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Guangren Hospital Affiliated to School of Medicine of Xi'an Jiaotong University, No. 21 Jiefang Road, Xi'an, Shaanxi, 710004, People's Republic of China.
| | - Bochang Lv
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Guangren Hospital Affiliated to School of Medicine of Xi'an Jiaotong University, No. 21 Jiefang Road, Xi'an, Shaanxi, 710004, People's Republic of China.
| |
Collapse
|
26
|
Kuehn S, Hurst J, Rensinghoff F, Tsai T, Grauthoff S, Satgunarajah Y, Dick HB, Schnichels S, Joachim SC. Degenerative effects of cobalt-chloride treatment on neurons and microglia in a porcine retina organ culture model. Exp Eye Res 2017; 155:107-120. [PMID: 28089775 DOI: 10.1016/j.exer.2017.01.003] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2016] [Revised: 12/20/2016] [Accepted: 01/11/2017] [Indexed: 01/08/2023]
Abstract
In order to understand the pathological processes of retinal diseases, experimental models are necessary. Cobalt, as part of the vitamin B12 complex, is important for neuronal integrity. However, it is known that high quantities of cobalt induce cytotoxic mechanisms via hypoxia mimicry. Therefore, we tested the degenerative effect of cobalt chloride (CoCl2) on neurons and microglia in a porcine retina organ culture model. Organotypic cultures of porcine retinas were cultured and treated with different concentrations of CoCl2 (0, 100, 300 and 500 μM) for 48 h. After four and eight days, CoCl2 induced a strong degeneration of the porcine retina, starting at 300 μM. A loss of retinal ganglion cells (RGCs, Brn-3a), amacrine cells (calretinin) and bipolar cells (PKCα) was observed. Additionally, a high expression of hypoxia induced factor-1a (HIF-1a) and heat shock protein 70 (HSP70) was noted at both points in time. Also, the Caspase 3 protein was activated and P21 expression was induced. However, only at day four, the Bax/Bcl-2 ratio was increased. The effect of CoCl2 was not restricted to neurons. CoCl2 concentrations reduced the microglia amount (Iba1) and activity (Iba1 + Fcγ-Receptor) at both points in time. These damaging effects on microglia were surprising, since CoCl2 causes hypoxia and a pro-inflammatory environment. However, high concentrations of CoCl2 also seem to be toxic to these cells. Similar degenerative mechanisms as in comparison to retinal ischemia animal models were observed. In summary, an effective and reproducible hypoxia-mimicking organotypic model for retinal degeneration was established, which is easy to handle and ready for drug studies.
Collapse
Affiliation(s)
- S Kuehn
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - J Hurst
- University Eye Hospital Tübingen, Centre for Ophthalmology, Elfriede-Aulhorn-Str. 7, 72076, Tübingen, Germany
| | - F Rensinghoff
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - T Tsai
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - S Grauthoff
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - Y Satgunarajah
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - H B Dick
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany
| | - S Schnichels
- University Eye Hospital Tübingen, Centre for Ophthalmology, Elfriede-Aulhorn-Str. 7, 72076, Tübingen, Germany.
| | - S C Joachim
- Experimental Eye Research, Eye Hospital, Ruhr-University Bochum, In der Schornau 23-25, 44892 Bochum, Germany.
| |
Collapse
|
27
|
Carbon monoxide treatment reduces microglial activation in the ischemic rat retina. Graefes Arch Clin Exp Ophthalmol 2016; 254:1967-1976. [PMID: 27443355 DOI: 10.1007/s00417-016-3435-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2016] [Revised: 06/06/2016] [Accepted: 07/04/2016] [Indexed: 12/21/2022] Open
Abstract
PURPOSE Ischemia and reperfusion (I/R) injury damages retinal neurons. Retinal injury is accompanied by activation of microglia, which scavenge the dead or dying neurons, but increasing evidence now indicates that amoeboid-shaped microglia cells activated in the brain after ischemia have neurotoxic and damaging properties in their own right. A previous study showed that postconditioning with carbon monoxide (CO) protects retinal ganglion cells (RGCs) after I/R through anti-apoptotic and anti-inflammatory mechanisms. The present study was designed to investigate and quantify the activation of retinal microglia after I/R with and without CO postconditioning. METHODS Adult Sprague-Dawley rats underwent retinal ischemia by increasing the ocular pressure to 120 mmHg for 1 h through a needle inserted into the anterior chamber. Reperfusion was induced by removing the needle. After I/R, one group of animals was kept in a CO (250 ppm) atmosphere for 1 h; the other group was kept in room air (Air). At 1, 2, 3, and 7 days after I/R, the eyes were enucleated and fixed. Intracardiac blood was analyzed for systemic effects of CO or I/R. Retinal cross sections were taken from the middle third of the eye and were stained with anti-Iba-1. Microglia cells were graded as amoeboid or ramified phenotypes according to morphologic criteria. Retinal thicknesses were determined. RESULTS Evaluation of retinal tissue revealed a significant reduction of amoeboid microglia cells after I/R + CO when compared to the I/R + Air group. The peak number of amoeboid microglia was observed at day 2 post-I/R + Air. This rise was attenuated by CO postconditioning (815 versus 572 cells/mm2 for I/R + Air versus I/R + CO, respectively; p = 0.005). CO reduced and further postponed the peak in the numbers of amoeboid and ramified microglia cells in ischemic eyes and prevented microglial activation in the contralateral eyes. I/R-induced leucocytosis was inhibited by CO inhalation. The reduction of retinal thickness after I/R was more serious after Air inhalation when compared to the CO group. CONCLUSIONS Numerous activated microglia cells appear in the inner retina after I/R, and CO-treatment significantly attenuates this glial response. Antagonism of microglial activation may be a further neuroprotective effect of CO, apart from its direct anti-apoptotic capacity.
Collapse
|
28
|
Lv B, Huo F, Zhu Z, Xu Z, Dang X, Chen T, Zhang T, Yang X. Crocin Upregulates CX3CR1 Expression by Suppressing NF-κB/YY1 Signaling and Inhibiting Lipopolysaccharide-Induced Microglial Activation. Neurochem Res 2016; 41:1949-57. [PMID: 27084772 DOI: 10.1007/s11064-016-1905-1] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2015] [Revised: 03/24/2016] [Accepted: 03/28/2016] [Indexed: 11/26/2022]
Abstract
Glaucoma is a group of neurodegenerative diseases characterized by the progressive loss of retinal ganglion cells (RGCs) and optic nerve fibers. Microglial activation has been shown to be deleterious to RGCs and may participate in the progression of glaucoma. Crocin, one of the major active ingredients in saffron, has been found to inhibit microglial activation. However, the mechanism remains unclear. The aim of this study was to investigate whether crocin can inhibit lipopolysaccharide (LPS)-induced microglial activation and to clarify the mechanisms involved. The influence of crocin on primary RGCs and LPS-stimulated BV2 microglial cells survival was determined by the MTT and lactate dehydrogenase assays, or by flow cytometry. BV2 cells were pretreated with various concentrations of crocin for 2 h followed by 1 μg/mL LPS stimulation. Microglial markers and pro-inflammatory mediators were assessed by real-time PCR, western blot and ELISA. Furthermore, CX3CR1 expression was detected and the underlying mechanism was examined. The concentrations of crocin ranged from 0.1 to 1 μM, and did not show any cytotoxicity in RGC and BV2 cells. After crocin pretreatment, the expression of microglial markers (CD11b and Iba-1) and pro-inflammatory mediators (iNOS, COX-2, IL-1β, and TNF-α) induced by LPS were significantly decreased in a dose-dependent manner. Additionally, CX3CR1 expression was remarkably increased by crocin via the suppression of NF-κB/Yin Yang 1 (YY1) signaling in BV2 cells. In conclusion, crocin effectively suppresses microglial activation and upregulates CX3CR1 expression by suppressing NF-κB/YY1 signaling.
Collapse
Affiliation(s)
- Bochang Lv
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, 710004, People's Republic of China
| | - Fuquan Huo
- Department of Physiology and Pathophysiology, Key Laboratory of Environment and Genes Related to Diseases, Ministry of Education, Xi'an Jiaotong University School of Medicine, Xi'an, 710061, People's Republic of China
| | - Zhongqiao Zhu
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, 710004, People's Republic of China
| | - Zhiguo Xu
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, 710004, People's Republic of China
| | - Xiaojie Dang
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, 710004, People's Republic of China
| | - Tao Chen
- Department of Anatomy, Histology and Embryology and K. K. Leung Brain Research Centre, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Ting Zhang
- Department of Anatomy, Histology and Embryology and K. K. Leung Brain Research Centre, Fourth Military Medical University, Xi'an, 710032, People's Republic of China
| | - Xinguang Yang
- Shaanxi Ophthalmic Medical Center, Xi'an No. 4 Hospital, Affiliated Guangren Hospital, School of Medicine, Xi'an Jiaotong University, Xi'an, 710004, People's Republic of China.
| |
Collapse
|
29
|
Russo R, Varano GP, Adornetto A, Nucci C, Corasaniti MT, Bagetta G, Morrone LA. Retinal ganglion cell death in glaucoma: Exploring the role of neuroinflammation. Eur J Pharmacol 2016; 787:134-42. [PMID: 27044433 DOI: 10.1016/j.ejphar.2016.03.064] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2015] [Revised: 03/10/2016] [Accepted: 03/31/2016] [Indexed: 01/06/2023]
Abstract
In clinical glaucoma, as well as in experimental models, the loss of retinal ganglion cells occurs by apoptosis. This final event is preceded by inflammatory responses involving the activation of innate and adaptive immunity, with retinal and optic nerve resident glial cells acting as major players. Here we review the current literature on the role of neuroinflammation in neurodegeneration, focusing on the inflammatory molecular mechanisms involved in the pathogenesis and progression of the optic neuropathy.
Collapse
Affiliation(s)
- Rossella Russo
- Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy.
| | - Giuseppe Pasquale Varano
- Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Annagrazia Adornetto
- Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy
| | - Carlo Nucci
- Ophthalmology Unit, Department of Experimental Medicine and Surgery, University of Rome "Tor Vergata", Rome Italy
| | | | - Giacinto Bagetta
- Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy; University Center for Adaptive Disorders and Head Pain, Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Arcavacata di Rende, Italy
| | - Luigi Antonio Morrone
- Department of Pharmacy, Nutritional and Health Sciences, University of Calabria, Arcavacata di Rende, Italy; University Center for Adaptive Disorders and Head Pain, Section of Neuropharmacology of Normal and Pathological Neuronal Plasticity, University of Calabria, Arcavacata di Rende, Italy
| |
Collapse
|
30
|
Trost A, Lange S, Schroedl F, Bruckner D, Motloch KA, Bogner B, Kaser-Eichberger A, Strohmaier C, Runge C, Aigner L, Rivera FJ, Reitsamer HA. Brain and Retinal Pericytes: Origin, Function and Role. Front Cell Neurosci 2016; 10:20. [PMID: 26869887 PMCID: PMC4740376 DOI: 10.3389/fncel.2016.00020] [Citation(s) in RCA: 158] [Impact Index Per Article: 19.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2015] [Accepted: 01/18/2016] [Indexed: 12/13/2022] Open
Abstract
Pericytes are specialized mural cells located at the abluminal surface of capillary blood vessels, embedded within the basement membrane. In the vascular network these multifunctional cells fulfil diverse functions, which are indispensable for proper homoeostasis. They serve as microvascular stabilizers, are potential regulators of microvascular blood flow and have a central role in angiogenesis, as they for example regulate endothelial cell proliferation. Furthermore, pericytes, as part of the neurovascular unit, are a major component of the blood-retina/brain barrier. CNS pericytes are a heterogenic cell population derived from mesodermal and neuro-ectodermal germ layers acting as modulators of stromal and niche environmental properties. In addition, they display multipotent differentiation potential making them an intriguing target for regenerative therapies. Pericyte-deficiencies can be cause or consequence of many kinds of diseases. In diabetes, for instance, pericyte-loss is a severe pathological process in diabetic retinopathy (DR) with detrimental consequences for eye sight in millions of patients. In this review, we provide an overview of our current understanding of CNS pericyte origin and function, with a special focus on the retina in the healthy and diseased. Finally, we highlight the role of pericytes in de- and regenerative processes.
Collapse
Affiliation(s)
- Andrea Trost
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and OptometrySalzburg, Austria; Molecular Regenerative Medicine, Paracelsus Medical UniversitySalzburg, Austria
| | - Simona Lange
- Molecular Regenerative Medicine, Paracelsus Medical UniversitySalzburg, Austria; Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University SalzburgSalzburg, Austria
| | - Falk Schroedl
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and OptometrySalzburg, Austria; Anatomy, Paracelsus Medical UniversitySalzburg, Austria
| | - Daniela Bruckner
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Karolina A Motloch
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Barbara Bogner
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Alexandra Kaser-Eichberger
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Clemens Strohmaier
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Christian Runge
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and Optometry Salzburg, Austria
| | - Ludwig Aigner
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University SalzburgSalzburg, Austria; Anatomy, Paracelsus Medical UniversitySalzburg, Austria
| | - Francisco J Rivera
- Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University SalzburgSalzburg, Austria; Anatomy, Paracelsus Medical UniversitySalzburg, Austria
| | - Herbert A Reitsamer
- Research Program for Ophthalmology and Glaucoma Research, Paracelsus Medical University/SALK, University Clinic of Ophthalmology and OptometrySalzburg, Austria; Anatomy, Paracelsus Medical UniversitySalzburg, Austria
| |
Collapse
|
31
|
Maurya N, Agarwal NR, Ghosh I. Low-dose rotenone exposure induces early senescence leading to late apoptotic signaling cascade in human trabecular meshwork (HTM) cell line: An in vitro glaucoma model. Cell Biol Int 2015; 40:107-20. [PMID: 26524696 DOI: 10.1002/cbin.10561] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Accepted: 10/26/2015] [Indexed: 12/15/2022]
Abstract
This study aimed to determine whether the prolonged exposure of the human trabecular meshwork (HTM) cell line to a low dose (1 nM) of rotenone could simulate a glaucomatous-like condition and serve as a cellular model for its etiological analysis. Under 1-nM rotenone exposure for 24-72 h, HTM cells showed a decrease in cell viability as assessed by an MTT assay and showed mitochondrial dysfunction as assessed by measuring H2 DCFDA fluorescence; a decrease in ATP level was also observed. Flow cytometric analysis showed an increase in cellular size and granularity. Elevated AF showed initial senescence. LF staining with SBB and its spectrofluorometric quantification confirmed growth arrest. An accumulation of cytoplasmic myocilin, IL-6, and MMP-9 at 72 h of exposure supported glaucomatous induction. TEM revealed morphological changes in mitochondria and nuclei of treated cells. Signaling cascades were assessed by immunoblotting and immunocytochemical analysis. This study showed a shift in status of the cells from initial senescence to induction of apoptosis in the HTM cell line due to continuous low-dose exposure to rotenone; however, at 72 h, both senescence and apoptotic features are apparent in these cells. This is the first report that reveals the potential of a prolonged low-dose exposure of rotenone to simulate senescence in the HTM cell line to cause a glaucomatous condition.
Collapse
Affiliation(s)
- Nancy Maurya
- Biochemistry and Environmental Toxicology, Laboratory # 103, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Nupur Rani Agarwal
- Biochemistry and Environmental Toxicology, Laboratory # 103, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| | - Ilora Ghosh
- Biochemistry and Environmental Toxicology, Laboratory # 103, School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067, India
| |
Collapse
|