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Zhu Y, Guo Y, Guo P, Zhang J, He Y, Xia Y, Wei Z, Dai Y. Estrogen receptor β activation alleviates inflammatory bowel disease by suppressing NLRP3-dependent IL-1β production in macrophages via downregulation of intracellular calcium level. J Adv Res 2024:S2090-1232(24)00228-5. [PMID: 38844124 DOI: 10.1016/j.jare.2024.06.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 05/30/2024] [Accepted: 06/02/2024] [Indexed: 06/11/2024] Open
Abstract
INTRODUCTION Although several estrogen receptor β (ERβ) agonists have been reported to alleviate IBD, the pivotal mechanism remains obscure. OBJECTIVES To examine the effects and mechanisms of ERβ activation on cytokine/chemokine networks in colitis mice. METHODS Dextran sulfate sodium salt (DSS) and trinitro-benzene-sulfonic acid (TNBS) were used to induce mouse colitis model. Multiple molecular biological methods were employed to evaluate the severity of mouse colitis and the level of cytokine and/or chemokine. RESULTS Bioinformatics analysis, ELISA and immunofluorescence results showed that the targeted cytokines and/or chemokines associated with ERβ expression and activation is IL-1β, and the anti-colitis effect of ERβ activation was significantly attenuated by the overexpression of AAV9-IL-1β. Immunofluorescence analysis indicated that ERβ activation led to most evident downregulation of IL-1β expression in colonic macrophages as compared to monocytes and neutrophils. Given the pivotal roles of NLRP3, NLRC4, and AIM2 inflammasome activation in the production of IL-1β, we examined the influence of ERβ activation on inflammasome activity. ELISA and WB results showed that ERβ activation selectively blocked the NLRP3 inflammasome assembly-mediated IL-1β secretion. The calcium-sensing receptor (CaSR) and calcium signaling play crucial roles in the assembly of the NLRP3 inflammasome. WB and immunofluorescence results showed that ERβ activation reduced intracellular CaSR expression and calcium signaling in colonic macrophages. Combination with CaSR overexpression plasmid reversed the suppressive effect of ERβ activation on NLRP3 inflammasome assembly, and counteracting the downregulation of IL-1β secretion. CONCLUSION Our research uncovers that the anti-colitis effect of ERβ activation is accomplished through the reduction of IL-1β levels in colonic tissue, achieved by specifically decreasing CaSR expression in macrophages to lower intracellular calcium levels and inhibit NLRP3 inflammasome assembly-mediated IL-1β production.
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Affiliation(s)
- Yanrong Zhu
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Yilei Guo
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Pengxiang Guo
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Jing Zhang
- Department of Pharmacognosy, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Yue He
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Yufeng Xia
- Department of Pharmacognosy, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China
| | - Zhifeng Wei
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China.
| | - Yue Dai
- Department of Pharmacology of Chinese Materia Medica, School of Traditional Chinese Pharmacy, China Pharmaceutical University, 639 Long Mian Avenue, Nanjing 211198, China.
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Zhang Z, Liang F, Chang J, Shan X, Yin Z, Wang L, Li S. Autophagy in dry AMD: A promising therapeutic strategy for retinal pigment epithelial cell damage. Exp Eye Res 2024; 242:109889. [PMID: 38593971 DOI: 10.1016/j.exer.2024.109889] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/11/2024]
Abstract
Dry age-related macular degeneration (AMD) is a prevalent clinical condition that leads to permanent damage to central vision and poses a significant threat to patients' visual health. Although the pathogenesis of dry AMD remains unclear, there is consensus on the role of retinal pigment epithelium (RPE) damage. Oxidative stress and chronic inflammation are major contributors to RPE cell damage, and the NOD-like receptor thermoprotein structural domain-associated protein 3 (NLRP3) inflammasome mediates the inflammatory response leading to apoptosis in RPE cells. Furthermore, lipofuscin accumulation results in oxidative stress, NLRP3 activation, and the development of vitelliform lesions, a hallmark of dry AMD, all of which may contribute to RPE dysfunction. The process of autophagy, involving the encapsulation, recognition, and transport of accumulated proteins and dead cells to the lysosome for degradation, is recognized as a significant pathway for cellular self-protection and homeostasis maintenance. Recently, RPE cell autophagy has been discovered to be closely linked to the development of macular degeneration, positioning autophagy as a cutting-edge research area in the realm of dry AMD. In this review, we present an overview of how lipofuscin, oxidative stress, and the NLRP3 inflammasome damage the RPE through their respective causal mechanisms. We summarized the connection between autophagy, oxidative stress, and NLRP3 inflammatory cytokines. Our findings suggest that targeting autophagy improves RPE function and sustains visual health, offering new perspectives for understanding the pathogenesis and clinical management of dry AMD.
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Affiliation(s)
- Zhao Zhang
- Tianjin University of Chinese Medicine, Tianjin, 300193, China; The First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center of Traditional Chinese Medicine and Acupuncture and Moxibustion, Tianjin, 300193, China
| | - Fengming Liang
- The First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center of Traditional Chinese Medicine and Acupuncture and Moxibustion, Tianjin, 300193, China.
| | - Jun Chang
- Tianjin University of Chinese Medicine, Tianjin, 300193, China; The First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center of Traditional Chinese Medicine and Acupuncture and Moxibustion, Tianjin, 300193, China
| | - Xiaoqian Shan
- Tianjin University of Chinese Medicine, Tianjin, 300193, China; The First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center of Traditional Chinese Medicine and Acupuncture and Moxibustion, Tianjin, 300193, China
| | - Zhixian Yin
- Hebei University of Technology, School of Electronics and Information Engineering, Tianjin, 300401, China
| | - Li Wang
- The First Affiliated Hospital of Tianjin University of Traditional Chinese Medicine, National Clinical Research Center of Traditional Chinese Medicine and Acupuncture and Moxibustion, Tianjin, 300193, China
| | - Shujiao Li
- Eye Hospital, China Academy of Chinese Medical Sciences, Beijing, 100040, China
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Korhonen E. Inflammasome activation in response to aberrations of cellular homeostasis in epithelial cells from human cornea and retina. Acta Ophthalmol 2024; 102 Suppl 281:3-68. [PMID: 38386419 DOI: 10.1111/aos.16646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2024] [Accepted: 01/16/2024] [Indexed: 02/24/2024]
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Li B, Yang Z, Zhao X, Chen Y, Li D, Zhang L, Min H, Yu W, Shen M. Early onset drusen and RPE dysfunction in a patient with NLRP3-AID. Ocul Immunol Inflamm 2023; 31:1877-1880. [PMID: 36395369 DOI: 10.1080/09273948.2022.2113804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 08/11/2022] [Indexed: 11/18/2022]
Abstract
Retinal pigment epithelium (RPE) dysfunction, manifested as drusen formation and RPE mottling, is a characteristic lesion of aging. The mechanism of RPE dysfunction remains unknown. Previous animal studies have proven that the activation of NLRP3 inflammasome in RPE leads to apoptosis and pyroptosis, which may play a very important role in the development of age-related macular degeneration (AMD). However, there is a lack of clinical evidence to support the above hypothesis. Herein, we report a 38-year-old Chinese Han woman who had NLRP3-associated autoinflammatory disease (NLRP3-AID) with widely scattered drusen at the posterior pole in both eyes. NLRP3-AID is a rare disease caused by mutations of the NLRP3 gene, leading to NLRP3 inflammasome activation. This report of early-onset drusen provides clinical evidence that the NLRP3 inflammasome might contribute to the occurrence of RPE dysfunction and is a potential cause of age-related macular degeneration (AMD).
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Affiliation(s)
- Bing Li
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Zhikun Yang
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Xufeng Zhao
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Youxin Chen
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Donghui Li
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Li Zhang
- Department of Rheumatology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Key Laboratory of Rheumatology and Clinical Immunology, Ministry of Education, Beijing, Hebei, China
| | - Hanyi Min
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Weihong Yu
- Department of Ophthalmology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing, Hebei, China
| | - Min Shen
- Department of Rheumatology, State Key Laboratory of Complex Severe and Rare Diseases, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Key Laboratory of Rheumatology and Clinical Immunology, Ministry of Education, Beijing, Hebei, China
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Chen Z, Xiao K, Long Q. Intraperitoneal Injection of MCC950 Inhibits the Progression of Myopia in Form-Deprivation Myopic Mice. Int J Mol Sci 2023; 24:15839. [PMID: 37958819 PMCID: PMC10649398 DOI: 10.3390/ijms242115839] [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: 10/03/2023] [Revised: 10/22/2023] [Accepted: 10/30/2023] [Indexed: 11/15/2023] Open
Abstract
Myopia, one of the most prevalent ocular diseases worldwide, is projected to affect nearly half of the global population by 2050. The main cause of myopia in most patients is axial myopia, which primarily occurs due to the elongation of the eyeball, driven by changes in the extracellular matrix (ECM) of scleral cells. Previous studies have shown that NLRP3, an important inflammatory mediator, plays a critical role in regulating the expression of MMP-2 in the sclera. This, in turn, leads to a decrease in the expression of Collagen-1, a major component of the scleral ECM, triggering the remodeling of the scleral ECM. This study aimed to investigate the effect of MCC950, an inhibitor of NLRP3, on the progression of myopia using a mouse form-deprivation myopia (FDM) model. The FDM mouse model was constructed by subjecting three-week-old C57BL/6J mice to form-deprivation. The mice were divided into experimental (n = 10/group; FDM2M, FDM4M, FDM2W, and FDM4W) and control groups (n = 5/group). The experimental groups were further categorized based on the duration of form deprivation (2 and 4 weeks, labeled as 2 and 4, respectively) and the type of injection received (MCC950 or saline, labeled as M and W, respectively). MCC950 was injected at a concentration of 50 mg/mL, with a dose of 10 mg per kilogram of body weight. Meanwhile, the saline group received the same volume of saline. Refraction and axial length measurements were performed for each eye. The expression levels of NLRP3, caspase-1, IL-1β, IL-18, MMP-2, and Collagen-1 in the sclera were assessed using immunohistochemistry and Western blotting. The intraperitoneal injection of MCC950 did not significantly affect refraction or axial length in normal mice (p > 0.05). However, in FDM mice, MCC950 attenuated the elongation of the axial length and resulted in a smaller shift towards myopia compared to the saline group (FDM4M vs. FDM4W, p = 0.03 and p < 0.05, respectively). MCC950 decreased MMP-2 expression (p < 0.05) but increased Collagen-1 expression (p < 0.05) in the experimental eyes when compared to the saline group. Within the MCC950 group, the expression of MMP-2 was increased in the experimental eyes at 4 weeks (p < 0.05), while that of Collagen-1 was decreased (p < 0.05), which is consistent with changes in refractive error. Immunohistochemical analysis yielded similar results (p < 0.05). MCC950 also reduced the expression levels of NLRP3 (p = 0.03), caspase-1 (p < 0.05), IL-1β (p < 0.05), and IL-18 (p < 0.05) in the experimental eyes compared to the saline group. Within the MCC950 group, the expression levels of NLRP3 and caspase-1 were comparable between the experimental and control eyes (p > 0.05), whereas IL-18 expression was higher in experimental eyes (p < 0.05). IL-1β expression was higher in the experimental eyes only at week 4 (p < 0.05). The intraperitoneal injection of MCC950 can inhibit the progression of myopia in FDM mice, possibly by regulating collagen remodeling in the sclera through the NLRP3-MMP-2 signaling pathway. Therefore, MCC950 holds promise as a potential therapeutic agent for controlling the progression of myopia.
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Affiliation(s)
- Zhengyu Chen
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China; (Z.C.); (K.X.)
- Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Kang Xiao
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China; (Z.C.); (K.X.)
- Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing 100730, China
| | - Qin Long
- Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China; (Z.C.); (K.X.)
- Key Laboratory of Ocular Fundus Diseases, Chinese Academy of Medical Sciences, Beijing 100730, China
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Sekar R, Wooff Y, Cioanca AV, Kurera M, Ngo C, Man SM, Natoli R. Impairing Gasdermin D-mediated pyroptosis is protective against retinal degeneration. J Neuroinflammation 2023; 20:239. [PMID: 37864169 PMCID: PMC10588253 DOI: 10.1186/s12974-023-02927-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 10/10/2023] [Indexed: 10/22/2023] Open
Abstract
BACKGROUND Inflammasome activation and the subsequent release of pro-inflammatory cytokines including Interleukin 1β (IL-1β) have been widely reported to contribute to the progression of retinal degenerations, including age-related macular degeneration (AMD), the leading cause of blindness in the Western World. The role of Gasdermin D (GSDMD), a key executioner of pyroptosis following inflammasome activation, however, is less well-established. In this study we aimed to characterise the role of GSDMD in the healthy and degenerating retina, and uncover its role as a conduit for IL-1β release, including via extracellular vesicle (EV)-mediated release. METHODS GSDMD mutant and knockout mice, in vitro models of inflammation and a well-established in vivo model of retinal degeneration (photo-oxidative damage; PD) were utilised to explore the role and pathological contribution of GSDMD in regulating IL-1β release and propagating retinal inflammation. RNA sequencing of whole retinas was used to investigate GSDMD-mediated inflammation during degeneration. The role of EVs in GSDMD-mediated IL-1β release was investigated using nanoparticle tracking analysis, ELISA and EV inhibition paradigms. Finally, the therapeutic efficacy of targeting GSDMD was examined using GSDMD-specific siRNA. RESULTS We identified in this work that mice deficient in GSDMD had better-preserved retinal function, increased photoreceptor survivability and reduced inflammation. RNA-Seq analysis revealed that GSDMD may propagate inflammation in the retina via NF-κB signalling cascades and release of pro-inflammatory cytokines. We also showed that IL-1β was packaged and released via EV in a GSDMD-dependent manner. Finally, we demonstrated that impairing GSDMD function using RNAi or blocking EV release was able to reduce IL-1β content in cell-free supernatant and EV. CONCLUSIONS Taken together, these results suggest that pyroptotic pore-forming protein GSDMD plays a key role in the propagation of retinal inflammation, in particular via the release of EV-encapsulated IL-1β. Targeting GSDMD using genetic or pharmacological inhibitors may pose a therapeutic opportunity to dampen inflammatory cascades and delay the progression of retinal degeneration.
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Affiliation(s)
- Rakshanya Sekar
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
- School of Medicine and Psychology, The Australian National University, Canberra, ACT, Australia
| | - Yvette Wooff
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
- School of Medicine and Psychology, The Australian National University, Canberra, ACT, Australia
| | - Adrian V Cioanca
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
- School of Medicine and Psychology, The Australian National University, Canberra, ACT, Australia
| | - Melan Kurera
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Chinh Ngo
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Si Ming Man
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia
| | - Riccardo Natoli
- The John Curtin School of Medical Research, The Australian National University, Canberra, ACT, Australia.
- School of Medicine and Psychology, The Australian National University, Canberra, ACT, Australia.
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Maran JJ, Adesina MM, Green CR, Kwakowsky A, Mugisho OO. The central role of the NLRP3 inflammasome pathway in the pathogenesis of age-related diseases in the eye and the brain. Ageing Res Rev 2023; 88:101954. [PMID: 37187367 DOI: 10.1016/j.arr.2023.101954] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 05/08/2023] [Accepted: 05/12/2023] [Indexed: 05/17/2023]
Abstract
With increasing age, structural changes occur in the eye and brain. Neuronal death, inflammation, vascular disruption, and microglial activation are among many of the pathological changes that can occur during ageing. Furthermore, ageing individuals are at increased risk of developing neurodegenerative diseases in these organs, including Alzheimer's disease (AD), Parkinson's disease (PD), glaucoma and age-related macular degeneration (AMD). Although these diseases pose a significant global public health burden, current treatment options focus on slowing disease progression and symptomatic control rather than targeting underlying causes. Interestingly, recent investigations have proposed an analogous aetiology between age-related diseases in the eye and brain, where a process of chronic low-grade inflammation is implicated. Studies have suggested that patients with AD or PD are also associated with an increased risk of AMD, glaucoma, and cataracts. Moreover, pathognomonic amyloid-β and α-synuclein aggregates, which accumulate in AD and PD, respectively, can be found in ocular parenchyma. In terms of a common molecular pathway that underpins these diseases, the nucleotide-binding domain, leucine-rich-containing family, and pyrin domain-containing-3 (NLRP3) inflammasome is thought to play a vital role in the manifestation of all these diseases. This review summarises the current evidence regarding cellular and molecular changes in the brain and eye with age, similarities between ocular and cerebral age-related diseases, and the role of the NLRP3 inflammasome as a critical mediator of disease propagation in the eye and the brain during ageing.
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Affiliation(s)
- Jack J Maran
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Moradeke M Adesina
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Colin R Green
- Department of Ophthalmology and the New Zealand National Eye Centre, Faculty of Medical and Health Sciences, University of Auckland, New Zealand
| | - Andrea Kwakowsky
- Pharmacology and Therapeutics, School of Medicine, Galway Neuroscience Centre, University of Galway, Galway, Ireland
| | - Odunayo O Mugisho
- Buchanan Ocular Therapeutics Unit, Department of Ophthalmology and the New Zealand National Eye Centre, University of Auckland, New Zealand.
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P2X7 Is Involved in the Mouse Retinal Degeneration via the Coordinated Actions in Different Retinal Cell Types. Antioxidants (Basel) 2023; 12:antiox12010141. [PMID: 36671003 PMCID: PMC9854982 DOI: 10.3390/antiox12010141] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 01/02/2023] [Accepted: 01/03/2023] [Indexed: 01/11/2023] Open
Abstract
Adenosine triphosphate (ATP) released from dying cells with high concentrations is sensed as a danger signal by the P2X7 receptor. Sodium iodate (NaIO3) is an oxidative toxic agent, and its retinal toxicity has been used as the model of dry age-related macular degeneration (AMD). In this study, we used NaIO3-treated mice and cultured retinal cells, including BV-2 microglia, 661W photoreceptors, rMC1 Müller cells and ARPE-19 retinal epithelial cells, to understand the pathological action of P2X7 in retinal degeneration. We found that NaIO3 can significantly decrease the photoreceptor function by reducing a-wave and b-wave amplitudes in electroretinogram (ERG) analysis. Optical coherence tomography (OCT) analysis revealed the degeneration of retinal epithelium and ganglion cell layers. Interestingly, P2X7-/- mice were protected from the NaIO3-induced retinopathy and inflammatory NLRP3, IL-1β and IL-6 gene expression in the retina. Hematoxylin and eosin staining indicated that the retinal epithelium was less deteriorated in P2X7-/- mice compared to the WT group. Although P2X7 was barely detected in 661W, rMC1 and ARPE-19 cells, its gene and protein levels can be increased after NaIO3 treatment, leading to a synergistic cytotoxicity of BzATP [2'(3')-O-(4-benzoylbenzoyl)adenosine-5'-triphosphate tri(triethyleneammonium)salt] and NaIO3 administration in ARPE-19 cells. In conclusion, the paracrine action of the ATP/P2X7 axis via cell-cell communication is involved in NaIO3-induced retinal injury. Our results show that P2X7 antagonist might be a potential therapy in inflammation-related retinal degeneration.
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Marneros AG. Role of inflammasome activation in neovascular age-related macular degeneration. FEBS J 2023; 290:28-36. [PMID: 34767301 PMCID: PMC9185667 DOI: 10.1111/febs.16278] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/31/2021] [Accepted: 11/10/2021] [Indexed: 01/14/2023]
Abstract
Current anti-VEGF-A therapies inhibit choroidal neovascularization (CNV) in a subset of patients with neovascular age-related macular degeneration (NV-AMD). However, long-term treatment with such anti-VEGF-A therapies may impair physiological functions of the choriocapillaris and retina for which VEGF-A is needed. Moreover, disease progression can occur despite continuous anti-VEGF-A treatment. Thus, novel therapies for NV-AMD are urgently needed that target specifically disease-associated mechanisms without impairing growth factors and cellular pathways that are required for homeostatic functions of the retina and choroid. Inhibiting the inflammatory pathways that promote CNV would be such a promising novel approach that would likely not interfere with the normal functions of healthy retinal and choroidal cells. In this context, the inflammasome, a proinflammatory protein complex that promotes pathologic angiogenesis largely through generation of IL-1β and which has been reported to be activated in AMD, has become an area of much interest in the AMD field. However, most studies have focused mainly on the NLRP3 inflammasome in retinal pigment epithelial cells (RPE), and conflicting findings have resulted in an unclear picture of the role of the inflammasome for AMD pathogenesis. Recent data suggest that inflammasome activation in activated macrophages and retinal microglia but not in RPE cells promotes CNV. Furthermore, inflammasome activation can occur in CNV macrophages and microglia despite lack of NLRP3. Thus, activation of both NLRP3 inflammasomes as well as non-NLRP3 inflammasomes in macrophages/microglia at sites of CNV formation likely promote NV-AMD.
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Affiliation(s)
- Alexander G. Marneros
- Cutaneous Biology Research Center, Massachusetts General Hospital, and Department of Dermatology, Harvard Medical School,Corresponding author: Alexander G. Marneros, MD/PhD, Massachusetts General Hospital, Harvard Medical School, CNY-149, 13 Street, Charlestown, MA, 02129, USA, Tel.: 6176437170;
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Chen M, Rong R, Xia X. Spotlight on pyroptosis: role in pathogenesis and therapeutic potential of ocular diseases. J Neuroinflammation 2022; 19:183. [PMID: 35836195 PMCID: PMC9281180 DOI: 10.1186/s12974-022-02547-2] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2022] [Accepted: 07/05/2022] [Indexed: 11/10/2022] Open
Abstract
Pyroptosis is a programmed cell death characterized by swift plasma membrane disruption and subsequent release of cellular contents and pro-inflammatory mediators (cytokines), including IL‐1β and IL‐18. It differs from other types of programmed cell death such as apoptosis, autophagy, necroptosis, ferroptosis, and NETosis in terms of its morphology and mechanism. As a recently discovered form of cell death, pyroptosis has been demonstrated to be involved in the progression of multiple diseases. Recent studies have also suggested that pyroptosis is linked to various ocular diseases. In this review, we systematically summarized and discussed recent scientific discoveries of the involvement of pyroptosis in common ocular diseases, including diabetic retinopathy, age-related macular degeneration, AIDS-related human cytomegalovirus retinitis, glaucoma, dry eye disease, keratitis, uveitis, and cataract. We also organized new and emerging evidence suggesting that pyroptosis signaling pathways may be potential therapeutic targets in ocular diseases, hoping to provide a summary of overall intervention strategies and relevant multi-dimensional evaluations for various ocular diseases, as well as offer valuable ideas for further research and development from the perspective of pyroptosis.
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Affiliation(s)
- Meini Chen
- Eye Center of Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China.,Hunan Key Laboratory of Ophthalmology, Changsha, 410008, Hunan, People's Republic of China.,National Clinical Research Center for Geriatric Diseases (Xiangya Hospital), Changsha, 410008, Hunan, People's Republic of China
| | - Rong Rong
- Eye Center of Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China.,Hunan Key Laboratory of Ophthalmology, Changsha, 410008, Hunan, People's Republic of China.,National Clinical Research Center for Geriatric Diseases (Xiangya Hospital), Changsha, 410008, Hunan, People's Republic of China
| | - Xiaobo Xia
- Eye Center of Xiangya Hospital, Central South University, Changsha, 410008, Hunan, People's Republic of China. .,Hunan Key Laboratory of Ophthalmology, Changsha, 410008, Hunan, People's Republic of China. .,National Clinical Research Center for Geriatric Diseases (Xiangya Hospital), Changsha, 410008, Hunan, People's Republic of China.
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Raming K, Gliem M, Charbel Issa P, Birtel J, Herrmann P, Holz FG, Pfau M, Hess K. Visual Dysfunction and Structural Correlates in Sorsby Fundus Dystrophy. Am J Ophthalmol 2022; 234:274-284. [PMID: 34352251 DOI: 10.1016/j.ajo.2021.07.032] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 07/26/2021] [Accepted: 07/27/2021] [Indexed: 11/19/2022]
Abstract
PURPOSE To elucidate morphological determinants of rod and cone dysfunction in Sorsby fundus dystrophy (SFD), and to systematically compare visual function tests for interventional trials. DESIGN Prospective cross-sectional study. METHODS Patients with SFD (n = 16) and controls (n = 20) underwent visual function testing (best-corrected visual acuity [BCVA] and low luminance visual acuity [LLVA], contrast sensitivity, mesopic and dark-adapted (DA) fundus-controlled perimetry [FCP], rod-mediated dark adaptation [RMDA]), and multimodal imaging. Vision-related quality of life was evaluated. FCP and RMDA thresholds were analyzed using mixed models and structure-function correlation using machine learning (ML). Longitudinal data of 1 patient with high-dose vitamin A supplementation were available. RESULTS Although photopic BCVA was normative in SFD, LLVA was impaired (0.30 LogMAR [0.20; 0.45] vs 0.20 LogMAR [0.03; 0.28], P < .05). Scotopic visual function exhibited a delayed rod-intercept time (21 minutes [12.15; 21] vs 4.05 minutes [3.22; 5.36], P < .001), and marked DA cyan mean sensitivity loss (-11.80 dB [-3.47; -19.85]), paralleled by a reduced vision-related quality of life. ML-based structure-function correlation allowed prediction of mesopic, DA cyan, and red sensitivity with high accuracy (cross-validated mean absolute error: 4.36, 7.77, and 5.31 dB, respectively), whereas RMDA could be slowed even in the absence of fundus alterations on multimodal imaging. After high-dose vitamin A supplementation, RMDA and DA thresholds improved markedly. CONCLUSIONS Patients with SFD exhibit severely impaired scotopic visual function even in the absence of funduscopic alterations on multimodal imaging. In contrast to BCVA, scotopic visual function tests are suitable to quantify dysfunction in the early stages. Improvement of scotopic dysfunction after (off-label) high-dose vitamin A intake, as observed in one patient in our study, is compatible with the hypothesized local deficiency of vitamin A secondary to Bruch's membrane alterations.
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Affiliation(s)
- Kristin Raming
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Center for Rare Diseases (K.R., P.H., F.G.H., K.H.), University of Bonn, Bonn, Germany
| | - Martin Gliem
- Boehringer Ingelheim GmbH (M.G.), Ingelheim am Rhein, Germany
| | - Peter Charbel Issa
- Oxford Eye Hospital (P.C.I., J.B.,), Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom; Nuffield Laboratory of Ophthalmology (P.C.I., J.B.), Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Johannes Birtel
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Oxford Eye Hospital (P.C.I., J.B.,), Oxford University Hospitals NHS Foundation Trust, Oxford, United Kingdom; Nuffield Laboratory of Ophthalmology (P.C.I., J.B.), Department of Clinical Neurosciences, University of Oxford, Oxford, United Kingdom
| | - Philipp Herrmann
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Center for Rare Diseases (K.R., P.H., F.G.H., K.H.), University of Bonn, Bonn, Germany
| | - Frank G Holz
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Center for Rare Diseases (K.R., P.H., F.G.H., K.H.), University of Bonn, Bonn, Germany
| | - Maximilian Pfau
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Ophthalmic Genetics and Visual Function Branch (M.P.), National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA
| | - Kristina Hess
- From the Department of Ophthalmology (K.R., J.B., P.H., F.G.H., M.P., K.H.), University of Bonn, Bonn, Germany; Center for Rare Diseases (K.R., P.H., F.G.H., K.H.), University of Bonn, Bonn, Germany; Division of Epidemiology and Clinical Applications (K.H.), National Eye Institute, National Institutes of Health, Bethesda, Maryland, USA.
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12
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Corcoran SE, Halai R, Cooper MA. Pharmacological Inhibition of the Nod-Like Receptor Family Pyrin Domain Containing 3 Inflammasome with MCC950. Pharmacol Rev 2021; 73:968-1000. [PMID: 34117094 DOI: 10.1124/pharmrev.120.000171] [Citation(s) in RCA: 88] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Activation of the Nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome drives release of the proinflammatory cytokines interleukin (IL)-1β and IL-18 and induces pyroptosis (lytic cell death). These events drive chronic inflammation, and as such, NLRP3 has been implicated in a large number of human diseases. These range from autoimmune conditions, the simplest of which is NLRP3 gain-of-function mutations leading to an orphan disease, cryopyrin-associated period syndrome, to large disease burden indications, such as atherosclerosis, heart failure, stroke, neurodegeneration, asthma, ulcerative colitis, and arthritis. The potential clinical utility of NLRP3 inhibitors is substantiated by an expanding list of indications in which NLRP3 activation has been shown to play a detrimental role. Studies of pharmacological inhibition of NLRP3 in nonclinical models of disease using MCC950 in combination with human genetics, epigenetics, and analyses of the efficacy of biologic inhibitors of IL-1β, such as anakinra and canakinumab, can help to prioritize clinical trials of NLRP3-directed therapeutics. Although MCC950 shows excellent (nanomolar) potency and high target selectivity, its pharmacokinetic and toxicokinetic properties limited its therapeutic development in the clinic. Several improved, next-generation inhibitors are now in clinical trials. Hence the body of research in a plethora of conditions reviewed herein may inform analysis of the potential translational value of NLRP3 inhibition in diseases with significant unmet medical need. SIGNIFICANCE STATEMENT: The nod-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is one of the most widely studied and best validated biological targets in innate immunity. Activation of NLRP3 can be inhibited with MCC950, resulting in efficacy in more than 100 nonclinical models of inflammatory diseases. As several next-generation NLRP3 inhibitors are entering proof-of-concept clinical trials in 2020, a review of the pharmacology of MCC950 is timely and significant.
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Affiliation(s)
- Sarah E Corcoran
- Trinity College Dublin, Dublin, Ireland (S.E.C.); Inflazome, D6 Grain House, Mill Court, Great Shelford, Cambridge, United Kingdom (R.H., M.A.C.); and Institute for Molecular Bioscience, University of Queensland, Queensland, Australia (M.A.C.)
| | - Reena Halai
- Trinity College Dublin, Dublin, Ireland (S.E.C.); Inflazome, D6 Grain House, Mill Court, Great Shelford, Cambridge, United Kingdom (R.H., M.A.C.); and Institute for Molecular Bioscience, University of Queensland, Queensland, Australia (M.A.C.)
| | - Matthew A Cooper
- Trinity College Dublin, Dublin, Ireland (S.E.C.); Inflazome, D6 Grain House, Mill Court, Great Shelford, Cambridge, United Kingdom (R.H., M.A.C.); and Institute for Molecular Bioscience, University of Queensland, Queensland, Australia (M.A.C.)
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13
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Chen J, Tchivelekete GM, Zhou X, Tang W, Liu F, Liu M, Zhao C, Shu X, Zeng Z. Anti-inflammatory activities of Gardenia jasminoides extracts in retinal pigment epithelial cells and zebrafish embryos. Exp Ther Med 2021; 22:700. [PMID: 34007309 PMCID: PMC8120509 DOI: 10.3892/etm.2021.10132] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 03/19/2021] [Indexed: 12/15/2022] Open
Abstract
Age-related macular degeneration (AMD) is the most common cause of visual impairment in developed countries. Inflammation serves a critical role in the pathogenesis of AMD. Gardenia jasminoides is found in several regions of China and is traditionally used as an organic yellow dye but has also been widely used as a therapeutic agent in numerous diseases, including inflammation, depression, hepatic and vascular disorders, which may reflect the variability of functional compounds that are present in Gardenia jasminoides extracts (GJE). To investigate the therapeutic potential of GJE for AMD, ARPE-19 cells were treated with lipopolysaccharide (LPS) or LPS plus GJE. GJE significantly decreased LPS-induced expression of proinflammatory cytokines, including IL-1β, IL-6 and TNF-α. In the in vivo study, GJE inhibited CuSO4-induced migration of primitive macrophages to the lateral line in zebrafish embryos. GJE also attenuated expression of cytokines (IL-1β, IL-6 and TNF-α), NFKB activating protein (nkap) and TLR4 in ARPE-19 cells. The results of the present study demonstrated the anti-inflammatory potential of GJE in vitro and in vivo, and suggested GJE as a therapeutic candidate for AMD.
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Affiliation(s)
- Jianrong Chen
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China
| | | | - Xinzhi Zhou
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, G4 0BA, UK
| | - Weizhuo Tang
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China
| | - Fang Liu
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China
| | - Minzhuo Liu
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China
| | - Chenxi Zhao
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China
| | - Xinhua Shu
- Department of Biological and Biomedical Sciences, Glasgow Caledonian University, Glasgow, G4 0BA, UK.,Department of Vision Science, Glasgow Caledonian University, Glasgow, G4 0BA, UK.,School of Basic Medical Sciences, Shaoyang University, Shaoyang, Hunan 422000, P.R. China
| | - Zhihong Zeng
- College of Biological and Environmental Engineering, Changsha University, Changsha, Hunan 410022, P.R. China.,Hunan Provincial Key Laboratory of Nutrition and Quality Control Aquatic Animals, Changsha, Hunan 410022, P.R. China
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14
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Malsy J, Alvarado AC, Lamontagne JO, Strittmatter K, Marneros AG. Distinct effects of complement and of NLRP3- and non-NLRP3 inflammasomes for choroidal neovascularization. eLife 2020; 9:60194. [PMID: 33305736 PMCID: PMC7732340 DOI: 10.7554/elife.60194] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 11/05/2020] [Indexed: 12/16/2022] Open
Abstract
NLRP3 inflammasome activation and complement-mediated inflammation have been implicated in promoting choroidal neovascularization (CNV) in age-related macular degeneration (AMD), but central questions regarding their contributions to AMD pathogenesis remain unanswered. Key open questions are (1) whether NLRP3 inflammasome activation mainly in retinal pigment epithelium (RPE) or rather in non-RPE cells promotes CNV, (2) whether inflammasome activation in CNV occurs via NLRP3 or also through NLRP3-independent mechanisms, and (3) whether complement activation induces inflammasome activation in CNV. Here we show in a neovascular AMD mouse model that NLRP3 inflammasome activation in non-RPE cells but not in RPE cells promotes CNV. We demonstrate that both NLRP3-dependent and NLRP3-independent inflammasome activation mechanisms induce CNV. Finally, we find that complement and inflammasomes promote CNV through independent mechanisms. Our findings uncover an unexpected role of non-NLRP3 inflammasomes for CNV and suggest that combination therapies targeting inflammasomes and complement may offer synergistic benefits to inhibit CNV.
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Affiliation(s)
- Jakob Malsy
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States.,Department of Ophthalmology, University of Halle, Halle, Germany
| | - Andrea C Alvarado
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Joseph O Lamontagne
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Karin Strittmatter
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States
| | - Alexander G Marneros
- Cutaneous Biology Research Center, Massachusetts General Hospital and Harvard Medical School, Boston, United States
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15
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Abstract
NLRP3 is a cytosolic receptor member of the nucleotide-binding oligomerization domain NOD-like receptor family that surveys the intracellular environment for the presence of infection, pathogens, and metabolic alarms. Although the surveillance activity of NLRP3 is required to protect the host from several pathogens, uncontrolled activity can be detrimental to the host. Pharmacological and genetic strategies limiting NLRP3 inflammasome activation have been shown to be beneficial in a wide range of experimental models, from common pathologies such as arthritis, cardiovascular disease, and metabolic syndromes to rare genetic disorders such as cryopyrin-associated periodic syndrome. Thus, compounds that prevent NLRP3 inflammasome activation are of common interest with relevant therapeutic potential. The focus of this review is recent developments in NLRP3 inflammasome inhibitors.
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16
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Caspase-1-dependent inflammasomes mediate photoreceptor cell death in photo-oxidative damage-induced retinal degeneration. Sci Rep 2020; 10:2263. [PMID: 32041990 PMCID: PMC7010818 DOI: 10.1038/s41598-020-58849-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 01/06/2020] [Indexed: 01/14/2023] Open
Abstract
Activation of the inflammasome is involved in the progression of retinal degenerative diseases, in particular, in the pathogenesis of Age-Related Macular Degeneration (AMD), with NLRP3 activation the focus of many investigations. In this study, we used genetic and pharmacological approaches to explore the role of the inflammasome in a mouse model of retinal degeneration. We identify that Casp1/11−/− mice have better-preserved retinal function, reduced inflammation and increased photoreceptor survivability. While Nlrp3−/− mice display some level of preservation of retinal function compared to controls, pharmacological inhibition of NLRP3 did not protect against photoreceptor cell death. Further, Aim2−/−, Nlrc4−/−, Asc−/−, and Casp11−/− mice show no substantial retinal protection. We propose that CASP-1-associated photoreceptor cell death occurs largely independently of NLRP3 and other established inflammasome sensor proteins, or that inhibition of a single sensor is not sufficient to repress the inflammatory cascade. Therapeutic targeting of CASP-1 may offer a more promising avenue to delay the progression of retinal degenerations.
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17
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Gao J, Cui JZ, Wang A, Chen HHR, Fong A, Matsubara JA. The reduction of XIAP is associated with inflammasome activation in RPE: implications for AMD pathogenesis. J Neuroinflammation 2019; 16:171. [PMID: 31438981 PMCID: PMC6706877 DOI: 10.1186/s12974-019-1558-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Accepted: 08/14/2019] [Indexed: 02/06/2023] Open
Abstract
Background Age-related macular degeneration (AMD) is a multifactorial chronic disease of the eye. Several candidate pathways have been hypothesized to play a role in AMD pathogenesis. Our work and those of others suggests inflammasome activity as a mechanism associated with retinal pigment epithelial (RPE) cell demise. X-linked inhibitor of apoptosis protein (XIAP), an anti-apoptosis factor, has recently been shown to regulate inflammasome activity in non-ocular cells. The purpose of this study is to characterize XIAP’s regulatory role in RPE. Methods Protein lysates of eye tissues from rats (vinpocetine- or aurin tricarboxylic acid complex-treated, ATAC, vs naïve) and mice (wild type vs Caspase-4−/−) were utilized to analyze XIAP protein levels. Immunohistochemistry was used to detect NLRP3 levels in the RPE layer. In vitro inflammasome activation on RPE cells was achieved with L-leucyl-L-leucine methyl ester (Leu-Leu-OMe) stimulation. Levels of XIAP mRNA and 18S RNA were quantified by RT-PCR. Cell culture supernatants were tested directly for secreted IL-1β by ELISA or concentrated for the detection of secreted IL-18 by western blot. Protein lysates from RPE in cell culture were collected for the measurement of cleaved caspase-1 p20, XIAP, and GAPDH. Data are presented as Mean ± SD. p < 0.05 is considered statistically significant. Results The XIAP protein level was significantly increased when the inflammasome was inhibited at the “activation” step by ATAC, but not the “priming” step, in vivo. Concomitantly, NLRP3 immunoreactivity was lower in the RPE layer of animals fed with ATAC. In mice where caspase-1 cleavage was impaired by the genetic deficiency in caspase-4, the XIAP protein level increased in eye tissues. In RPE cell culture, Leu-Leu-OMe stimulation led to caspase-1 cleavage, cytokine secretion, and XIAP reduction, which can be abolished by Z-YVAD-FMK. When XIAP siRNA was given as a pre-treatment to RPE in vitro, Leu-Leu-OMe induced IL-1β/IL-18 secretion was enhanced, whereas overexpressing XIAP reduced IL-1β secretion under inflammasome activation, both compared to controls cells. Conclusions Together, these data suggest XIAP-mediated inhibition of inflammasome activity in RPE may provide insights into the biological consequences of inflammasome activation in RPE and reveals the caspase-1/XIAP/IL-1β/IL-18 axis as a target for broader applications in AMD biology and treatment design. Electronic supplementary material The online version of this article (10.1186/s12974-019-1558-5) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Jiangyuan Gao
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada
| | - Jing Z Cui
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada
| | - Aikun Wang
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada
| | - Hao Hang Rachel Chen
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada
| | - Alison Fong
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada
| | - Joanne A Matsubara
- Department of Ophthalmology and Visual Sciences, Faculty of Medicine, Eye Care Centre, University of British Columbia, 2550 Willow Street, Vancouver, BC, V5Z 3N9, Canada.
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18
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Lu W, Campagno KE, Tso HY, Cenaj A, Laties AM, Carlsson LG, Mitchell CH. Oral Delivery of the P2Y12 Receptor Antagonist Ticagrelor Prevents Loss of Photoreceptors in an ABCA4-/- Mouse Model of Retinal Degeneration. Invest Ophthalmol Vis Sci 2019; 60:3046-3053. [PMID: 31319418 PMCID: PMC6640265 DOI: 10.1167/iovs.19-27241] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 06/10/2019] [Indexed: 01/22/2023] Open
Abstract
Purpose Accumulation of lysosomal waste is linked to neurodegeneration in multiple diseases, and pharmacologic enhancement of lysosomal activity is hypothesized to reduce pathology. An excessive accumulation of lysosomal-associated lipofuscin waste and an elevated lysosomal pH occur in retinal pigment epithelial cells of the ABCA4-/- mouse model of Stargardt's retinal degeneration. As treatment with the P2Y12 receptor antagonist ticagrelor was previously shown to lower lysosomal pH and lipofuscin-like autofluorescence in these cells, we asked whether oral delivery of ticagrelor also prevented photoreceptor loss. Methods Moderate light exposure was used to accelerate photoreceptor loss in albino ABCA4-/- mice as compared to BALB/c controls. Ticagrelor (0.1%-0.15%) was added to mouse chow for between 1 and 10 months. Photoreceptor function was determined with electroretinograms, while cell survival was determined using optical coherence tomography and histology. Results Protection by ticagrelor was demonstrated functionally by using the electroretinogram, as ticagrelor-treated ABCA4-/- mice had increased a- and b-waves compared to untreated mice. Mice receiving ticagrelor treatment had a thicker outer nuclear layer, as measured with both optical coherence tomography and histologic sections. Ticagrelor decreased expression of LAMP1, implicating enhanced lysosomal function. No signs of retinal bleeding were observed after prolonged treatment with ticagrelor. Conclusions Oral treatment with ticagrelor protected photoreceptors in the ABCA4-/- mouse, which is consistent with enhanced lysosomal function. As mouse ticagrelor exposure levels were clinically relevant, the drug may be of benefit in preventing the loss of photoreceptors in Stargardt's disease and other neurodegenerations associated with lysosomal dysfunction.
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Affiliation(s)
- Wennan Lu
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Keith E. Campagno
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Huen-Yee Tso
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Aurora Cenaj
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Alan M. Laties
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
| | - Leif G. Carlsson
- Bioscience Cardiovascular Research and Early Development Cardiovascular, Renal and Metabolism BioPhamaceuticals R&D, AstraZeneca, Gothenburg, Sweden
| | - Claire H. Mitchell
- Department of Anatomy and Cell Biology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
- Department of Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
- Department of Physiology, University of Pennsylvania, Philadelphia, Pennsylvania, United States
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