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Ravel-Godreuil C, Roy ER, Puttapaka SN, Li S, Wang Y, Yuan X, Eltzschig HK, Cao W. Transcriptional Responses of Different Brain Cell Types to Oxygen Decline. Brain Sci 2024; 14:341. [PMID: 38671993 PMCID: PMC11048388 DOI: 10.3390/brainsci14040341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
Brain hypoxia is associated with a wide range of physiological and clinical conditions. Although oxygen is an essential constituent of maintaining brain functions, our understanding of how specific brain cell types globally respond and adapt to decreasing oxygen conditions is incomplete. In this study, we exposed mouse primary neurons, astrocytes, and microglia to normoxia and two hypoxic conditions and obtained genome-wide transcriptional profiles of the treated cells. Analysis of differentially expressed genes under conditions of reduced oxygen revealed a canonical hypoxic response shared among different brain cell types. In addition, we observed a higher sensitivity of neurons to oxygen decline, and dissected cell type-specific biological processes affected by hypoxia. Importantly, this study establishes novel gene modules associated with brain cells responding to oxygen deprivation and reveals a state of profound stress incurred by hypoxia.
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Affiliation(s)
- Camille Ravel-Godreuil
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Ethan R. Roy
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Srinivas N. Puttapaka
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
- Division of Gastroenterology, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Sanming Li
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Yanyu Wang
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Xiaoyi Yuan
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Holger K. Eltzschig
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
| | - Wei Cao
- Department of Anesthesiology, Critical Care and Pain Medicine, McGovern Medical School, University of Texas Health Science Center at Houston, Houston, TX 77030, USA; (C.R.-G.); (E.R.R.); (S.N.P.); (S.L.); (Y.W.); (X.Y.); (H.K.E.)
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Böhm EW, Buonfiglio F, Voigt AM, Bachmann P, Safi T, Pfeiffer N, Gericke A. Oxidative stress in the eye and its role in the pathophysiology of ocular diseases. Redox Biol 2023; 68:102967. [PMID: 38006824 DOI: 10.1016/j.redox.2023.102967] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 11/10/2023] [Accepted: 11/14/2023] [Indexed: 11/27/2023] Open
Abstract
Oxidative stress occurs through an imbalance between the generation of reactive oxygen species (ROS) and the antioxidant defense mechanisms of cells. The eye is particularly exposed to oxidative stress because of its permanent exposure to light and due to several structures having high metabolic activities. The anterior part of the eye is highly exposed to ultraviolet (UV) radiation and possesses a complex antioxidant defense system to protect the retina from UV radiation. The posterior part of the eye exhibits high metabolic rates and oxygen consumption leading subsequently to a high production rate of ROS. Furthermore, inflammation, aging, genetic factors, and environmental pollution, are all elements promoting ROS generation and impairing antioxidant defense mechanisms and thereby representing risk factors leading to oxidative stress. An abnormal redox status was shown to be involved in the pathophysiology of various ocular diseases in the anterior and posterior segment of the eye. In this review, we aim to summarize the mechanisms of oxidative stress in ocular diseases to provide an updated understanding on the pathogenesis of common diseases affecting the ocular surface, the lens, the retina, and the optic nerve. Moreover, we discuss potential therapeutic approaches aimed at reducing oxidative stress in this context.
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Affiliation(s)
- Elsa Wilma Böhm
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany.
| | - Francesco Buonfiglio
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Anna Maria Voigt
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Philipp Bachmann
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Tarek Safi
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Norbert Pfeiffer
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany
| | - Adrian Gericke
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131, Mainz, Germany.
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Zuo Z, Zhang Z, Zhang S, Fan B, Li G. The Molecular Mechanisms Involved in Axonal Degeneration and Retrograde Retinal Ganglion Cell Death. DNA Cell Biol 2023; 42:653-667. [PMID: 37819746 DOI: 10.1089/dna.2023.0180] [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] [Indexed: 10/13/2023] Open
Abstract
Axonal degeneration is a pathologic change common to multiple retinopathies and optic neuropathies. Various pathologic factors, such as mechanical injury, inflammation, and ischemia, can damage retinal ganglion cell (RGC) somas and axons, eventually triggering axonal degeneration and RGC death. The molecular mechanisms of somal and axonal degeneration are distinct but also overlap, and axonal degeneration can result in retrograde somal degeneration. While the mitogen-activated protein kinase pathway acts as a central node in RGC axon degeneration, several newly discovered molecules, such as sterile alpha and Toll/interleukin-1 receptor motif-containing protein 1 and nicotinamide mononucleotide adenylyltransferase 2, also play a critical role in this pathological process following different types of injury. Therefore, we summarize the types of injury that cause RGC axon degeneration and retrograde RGC death and important underlying molecular mechanisms, providing a reference for the identification of targets for protecting axons and RGCs.
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Affiliation(s)
- Zhaoyang Zuo
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Ziyuan Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Siming Zhang
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Bin Fan
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
| | - Guangyu Li
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun, China
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Liu Y, Yang X, Li H, Li D, Zou Y, Gong B, Yu M. Characteristics of Autophagy-Related Genes, Diagnostic Models, and Their Correlation with Immune Infiltration in Keratoconus. J Inflamm Res 2023; 16:3763-3781. [PMID: 37663760 PMCID: PMC10474872 DOI: 10.2147/jir.s420164] [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: 05/21/2023] [Accepted: 08/23/2023] [Indexed: 09/05/2023] Open
Abstract
Purpose Keratoconus (KTCN) is one of the most common degenerative keratopathies, significantly affecting vision and even leading to blindness. This study identifies potential biomarkers of KTCN based on the characterization of autophagy-related genes (ARGs) and the construction of a diagnostic model; and explores their relevance to immune infiltrating cells in KTCN. Methods Gene Expression Omnibus (GEO) data were downloaded and ARGs were acquired from GeneCards and Molecular Signatures Database (MSigDB). Autophagy-related differential expression genes (ARDEGs) were discovered through the integration of differentially expressed genes (DEGs) with ARGs, while hub genes of KTCN were discovered by protein-protein interaction (PPI) network analysis. The probable biological roles of these hub ARDEGs were examined using functional enrichment analysis, and a KTCN diagnostic model was generated using the least absolute shrinkage and selection operator (LASSO) regression analysis. We also employed the CIBERSORTx and ssGSEA algorithms to identify potential regulatory pathways to compare the abundance of immune cell infiltrates and their association with hub genes. Finally, the hub gene expression levels were confirmed using validation datasets as well as blood samples from KTCN and healthy individuals. Results In this study, we identified 12 hub ARDEGs, of which 9 genes were substantially distinct between KTCN patients and normal groups. The LASSO risk score was used to generate the nomogram, and the calibration curve evaluated the model's effective diagnostic performance (C index of 0.961). Patients with KTCN had greater percentages of M2 Macrophages and Gamma delta T cells, according to CIBERSORTx and ssGSEA. The outcomes of the bioinformatics analysis were supported by the DDIT3 and BINP3 expression levels in KTCN patients and healthy controls, according to the qRT-PCR data. Conclusion Five biomarkers (CFTR, PLIN2, DDIT3, BAG3, and BNIP3) and diagnostic models offer fresh perspectives on identifying and managing KTCN.
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Affiliation(s)
- Yi Liu
- Department of Ophthalmology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, People’s Republic of China
- School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
| | - Xu Yang
- School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
| | - Huan Li
- School of Medicine, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Department of Health Management, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
| | - Dongfeng Li
- Department of Ophthalmology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, People’s Republic of China
| | - Yuhao Zou
- Department of Ophthalmology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, People’s Republic of China
| | - Bo Gong
- Department of Health Management, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Human Disease Genes Key Laboratory of Sichuan Province and Institute of Laboratory Medicine, Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Research Unit for Blindness Prevention of Chinese Academy of Medical Sciences (2019RU026), Sichuan Academy of Medical Sciences & Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
| | - Man Yu
- Department of Ophthalmology, Sichuan Provincial People’s Hospital, University of Electronic Science and Technology of China, Chengdu, People’s Republic of China
- Chinese Academy of Sciences Sichuan Translational Medicine Research Hospital, Chengdu, People’s Republic of China
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Buonfiglio F, Böhm EW, Pfeiffer N, Gericke A. Oxidative Stress: A Suitable Therapeutic Target for Optic Nerve Diseases? Antioxidants (Basel) 2023; 12:1465. [PMID: 37508003 PMCID: PMC10376185 DOI: 10.3390/antiox12071465] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 07/17/2023] [Accepted: 07/18/2023] [Indexed: 07/30/2023] Open
Abstract
Optic nerve disorders encompass a wide spectrum of conditions characterized by the loss of retinal ganglion cells (RGCs) and subsequent degeneration of the optic nerve. The etiology of these disorders can vary significantly, but emerging research highlights the crucial role of oxidative stress, an imbalance in the redox status characterized by an excess of reactive oxygen species (ROS), in driving cell death through apoptosis, autophagy, and inflammation. This review provides an overview of ROS-related processes underlying four extensively studied optic nerve diseases: glaucoma, Leber's hereditary optic neuropathy (LHON), anterior ischemic optic neuropathy (AION), and optic neuritis (ON). Furthermore, we present preclinical findings on antioxidants, with the objective of evaluating the potential therapeutic benefits of targeting oxidative stress in the treatment of optic neuropathies.
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Affiliation(s)
- Francesco Buonfiglio
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany; (E.W.B.); (N.P.)
| | | | | | - Adrian Gericke
- Department of Ophthalmology, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrasse 1, 55131 Mainz, Germany; (E.W.B.); (N.P.)
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Abstract
Purpose: Retinal ganglion cell death occurs during the glaucoma pathological process, and it is significant because of the poor regeneration capacity of retinal ganglion cells. With a constantly increasing understanding of retinal cell death mechanisms, we now know that simply blocking a specific mechanism of cell death might not prevent retinal ganglion cell death. This review aimed to summarize the mechanisms of retinal cell death in glaucoma models and discuss the caveats in restoring visual function in these studies.Methods: A literature search was done on PubMed using key words including glaucoma, ocular hypertension, retinal ganglion cell, cell death, apoptosis, necroptosis, pyroptosis, ferroptosis, autophagic cell death, and parthanatos. The literature was reviewed to summarize the information about the lethal pathways of retinal ganglion cell in the glaucoma-like animal models.Results: Based on the purpose, 100 studies were selected and discussed in this review.Conclusions: The damage to ganglion cells in glaucoma-like animals can occur via multiple lethal pathways and the molecular mechanisms are still incompletely understood. Further investigations on the crosstalk between different cell death pathways and the common upstream regulators could augment the development of novel targeting agents for the curative treatment of glaucoma.
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Affiliation(s)
- Yuting Yang
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China
| | - Xinghuai Sun
- Department of Ophthalmology & Visual Science, Eye & ENT Hospital, Shanghai Medical College, Fudan University, Shanghai, China.,NHC Key Laboratory of Myopia, Chinese Academy of Medical Sciences, and Shanghai Key Laboratory of Visual Impairment and Restoration, Fudan University, Shanghai, China.,State Key Laboratory of Medical Neurobiology and MOE Frontiers Center for Brain Science, Institutes of Brain Science, Fudan University, Shanghai, China
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Zhang X, Xu P, Lin B, Deng X, Zhu J, Chen X, Liu S, Li R, Wang N, Chen L. Chimonanthus salicifolius attenuated vascular remodeling by alleviating endoplasmic reticulum stress in spontaneously hypertensive rats. Food Funct 2022; 13:6293-6305. [PMID: 35611700 DOI: 10.1039/d1fo04381a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Chimonanthus salicifolius (CS), the leaves of Chimonanthus salicifolius S. Y. Hu., is an effective tea to prevent and treat hypertension in China. This study aimed to explore the effect and mechanism of CS in the protection against vascular remodeling in hypertension. Spontaneously hypertensive rats (SHRs) were orally administered with aqueous extracts of CS for 6 months. The blood pressure and morphological changes of the aorta were measured. Their mechanisms were studied by combining chemical identification, network pharmacology analysis and validation in vivo. Hypertensive rats showed an impaired vascular structure and dyslipidemia as illustrated by the increase of the vascular media thickness and collagen deposition in the aorta. CS treatment exhibited significant beneficial effects on blood pressure control and aortal morphology. A total of 21 compounds from CS were identified, which were linked to 106 corresponding targeted genes for vascular remodeling. The network pharmacology predicted that CS prevented vascular remodeling through the endoplasmic reticulum stress pathway. The in vivo experiments further showed that CS treatment upregulated Glucose-Regulated Protein 78 and downregulated CCAAT-enhancer-binding protein homologous protein at both mRNA and protein levels, paralleling reduced apoptotic cells in the arterial wall. Additionally, CS diminished the low-density lipoprotein cholesterol levels, total cholesterol contents and triglyceride/high-density lipoprotein cholesterol ratios in the sera of SHRs, which might also contribute to its protection of vessels. Collectively, CS protects against vascular modeling by suppressing endoplasmic reticulum stress-related apoptosis in hypertension, and it could be a potential agent for the prevention and treatment of vascular modeling.
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Affiliation(s)
- Xiaoqin Zhang
- Department of Pharmacy, Lishui hospital of traditional Chinese medicine, Lishui, Zhejiang, 323000, China.
| | - Pingcui Xu
- Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, 310007, China.
| | - Bingfeng Lin
- Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, 310007, China.
| | - Xuehui Deng
- School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310007, China.
| | - Jiazhen Zhu
- School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310007, China.
| | - Xinyi Chen
- Department of Pharmacy, Lishui hospital of traditional Chinese medicine, Lishui, Zhejiang, 323000, China.
| | - Shuang Liu
- Department of Pharmacy, Lishui hospital of traditional Chinese medicine, Lishui, Zhejiang, 323000, China.
| | - Rui Li
- Department of Pharmacy, Lishui hospital of traditional Chinese medicine, Lishui, Zhejiang, 323000, China.
| | - Nani Wang
- Department of Medicine, Zhejiang Academy of Traditional Chinese Medicine, Hangzhou, Zhejiang, 310007, China. .,School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310007, China.
| | - Liping Chen
- Department of Pharmacy, Lishui hospital of traditional Chinese medicine, Lishui, Zhejiang, 323000, China. .,School of Pharmacy, Zhejiang Chinese Medical University, Hangzhou, Zhejiang, 310007, China.
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The Intertwined Roles of Oxidative Stress and Endoplasmic Reticulum Stress in Glaucoma. Antioxidants (Basel) 2022; 11:antiox11050886. [PMID: 35624748 PMCID: PMC9137739 DOI: 10.3390/antiox11050886] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2022] [Revised: 04/26/2022] [Accepted: 04/28/2022] [Indexed: 02/04/2023] Open
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide, and the burden of the disease continues to grow as the global population ages. Currently, the only treatment option is to lower intraocular pressure. A better understanding of glaucoma pathogenesis will help us to develop novel therapeutic options. Oxidative stress has been implicated in the pathogenesis of many diseases. Oxidative stress occurs when there is an imbalance in redox homeostasis, with reactive oxygen species producing processes overcoming anti-oxidant defensive processes. Oxidative stress works in a synergistic fashion with endoplasmic reticulum stress, to drive glaucomatous damage to trabecular meshwork, retinal ganglion cells and the optic nerve head. We discuss the oxidative stress and endoplasmic reticulum stress pathways and their connections including their key intermediary, calcium. We highlight therapeutic options aimed at disrupting these pathways and discuss their potential role in glaucoma treatment.
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McLaughlin T, Medina A, Perkins J, Yera M, Wang JJ, Zhang SX. Cellular stress signaling and the unfolded protein response in retinal degeneration: mechanisms and therapeutic implications. Mol Neurodegener 2022; 17:25. [PMID: 35346303 PMCID: PMC8962104 DOI: 10.1186/s13024-022-00528-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 03/04/2022] [Indexed: 12/22/2022] Open
Abstract
Background The retina, as part of the central nervous system (CNS) with limited capacity for self-reparation and regeneration in mammals, is under cumulative environmental stress due to high-energy demands and rapid protein turnover. These stressors disrupt the cellular protein and metabolic homeostasis, which, if not alleviated, can lead to dysfunction and cell death of retinal neurons. One primary cellular stress response is the highly conserved unfolded protein response (UPR). The UPR acts through three main signaling pathways in an attempt to restore the protein homeostasis in the endoplasmic reticulum (ER) by various means, including but not limited to, reducing protein translation, increasing protein-folding capacity, and promoting misfolded protein degradation. Moreover, recent work has identified a novel function of the UPR in regulation of cellular metabolism and mitochondrial function, disturbance of which contributes to neuronal degeneration and dysfunction. The role of the UPR in retinal neurons during aging and under disease conditions in age-related macular degeneration (AMD), retinitis pigmentosa (RP), glaucoma, and diabetic retinopathy (DR) has been explored over the past two decades. Each of the disease conditions and their corresponding animal models provide distinct challenges and unique opportunities to gain a better understanding of the role of the UPR in the maintenance of retinal health and function. Method We performed an extensive literature search on PubMed and Google Scholar using the following keywords: unfolded protein response, metabolism, ER stress, retinal degeneration, aging, age-related macular degeneration, retinitis pigmentosa, glaucoma, diabetic retinopathy. Results and conclusion We summarize recent advances in understanding cellular stress response, in particular the UPR, in retinal diseases, highlighting the potential roles of UPR pathways in regulation of cellular metabolism and mitochondrial function in retinal neurons. Further, we provide perspective on the promise and challenges for targeting the UPR pathways as a new therapeutic approach in age- and disease-related retinal degeneration.
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Affiliation(s)
- Todd McLaughlin
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA
| | - Andy Medina
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA
| | - Jacob Perkins
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA
| | - Maria Yera
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA.,Neuroscience Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Joshua J Wang
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA.,Neuroscience Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, USA
| | - Sarah X Zhang
- Department of Ophthalmology and Ira G. Ross Eye Institute, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, 955 Main Street, Buffalo, NY, 14203, USA. .,Neuroscience Program, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, USA. .,Department of Biochemistry, Jacobs School of Medicine and Biomedical Sciences, University at Buffalo, State University of New York, Buffalo, NY, USA.
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10
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Multifactorial Pathogenic Processes of Retinal Ganglion Cell Degeneration in Glaucoma towards Multi-Target Strategies for Broader Treatment Effects. Cells 2021; 10:cells10061372. [PMID: 34199494 PMCID: PMC8228726 DOI: 10.3390/cells10061372] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2021] [Revised: 05/14/2021] [Accepted: 05/29/2021] [Indexed: 02/06/2023] Open
Abstract
Glaucoma is a chronic neurodegenerative disease characterized by apoptosis of retinal ganglion cell (RGC) somas, degeneration of axons, and loss of synapses at dendrites and axon terminals. Glaucomatous neurodegeneration encompasses multiple triggers, multiple cell types, and multiple molecular pathways through the etiological paths with biomechanical, vascular, metabolic, oxidative, and inflammatory components. As much as intrinsic responses of RGCs themselves, divergent responses and intricate interactions of the surrounding glia also play decisive roles for the cell fate. Seen from a broad perspective, multitarget treatment strategies have a compelling pathophysiological basis to more efficiently manipulate multiple pathogenic processes at multiple injury sites in such a multifactorial neurodegenerative disease. Despite distinct molecular programs for somatic and axonal degeneration, mitochondrial dysfunction and glia-driven neuroinflammation present interdependent processes with widespread impacts in the glaucomatous retina and optic nerve. Since dysfunctional mitochondria stimulate inflammatory responses and proinflammatory mediators impair mitochondria, mitochondrial restoration may be immunomodulatory, while anti-inflammatory treatments protect mitochondria. Manipulation of these converging routes may thus allow a unified treatment strategy to protect RGC axons, somas, and synapses. This review presents an overview of recent research advancements with emphasis on potential treatment targets to achieve the best treatment efficacy to preserve visual function in glaucoma.
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11
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Wang J, Struebing FL, Geisert EE. Commonalities of optic nerve injury and glaucoma-induced neurodegeneration: Insights from transcriptome-wide studies. Exp Eye Res 2021; 207:108571. [PMID: 33844961 PMCID: PMC9890784 DOI: 10.1016/j.exer.2021.108571] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 03/28/2021] [Accepted: 04/02/2021] [Indexed: 02/03/2023]
Abstract
Glaucoma is a collection of diseases that lead to an irreversible vision loss due to damage of retinal ganglion cells (RGCs). Although the underlying events leading to RGC death are not fully understood, recent research efforts are beginning to define the genetic changes that play a critical role in the initiation and progression of glaucomatous injury and RGC death. Several genetic and experimental animal models have been developed to mimic glaucomatous neurodegeneration. These models differ in many respects but all result in the loss of RGCs. Assessing transcriptional changes across different models could provide a more complete perspective on the molecular drivers of RGC degeneration. For the past several decades, changes in the retinal transcriptome during neurodegeneration process were defined using microarray methods, RNA sequencing and now single cell RNA sequencing. It is understood that these methods have strengths and weaknesses due to technical differences and variations in the analytical tools used. In this review, we focus on the use of transcriptome-wide expression profiling of the changes occurring as RGCs are lost across different glaucoma models. Commonalities of optic nerve crush and glaucoma-induced neurodegeneration are identified and discussed.
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Affiliation(s)
- Jiaxing Wang
- Emory Eye Center, Department of Ophthalmology, Emory University, 1365B Clifton Road NE, Atlanta, GA, 30322, USA
| | - Felix L. Struebing
- Center for Neuropathology and Prion Research, Ludwig Maximilian University of Munich, Germany,Department for Translational Brain Research, German Center for Neurodegenerative Diseases (DZNE), Munich, Germany
| | - Eldon E. Geisert
- Emory Eye Center, Department of Ophthalmology, Emory University, 1365B Clifton Road NE, Atlanta, GA, 30322, USA,Corresponding author: (E.E. Geisert)
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12
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Straughn AR, Kelm NQ, Kakar SS. Withaferin A and Ovarian Cancer Antagonistically Regulate Skeletal Muscle Mass. Front Cell Dev Biol 2021; 9:636498. [PMID: 33718372 PMCID: PMC7947350 DOI: 10.3389/fcell.2021.636498] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2020] [Accepted: 02/05/2021] [Indexed: 01/06/2023] Open
Abstract
Cachexia is a complex wasting syndrome that overwhelmingly affects the majority of late-stage cancer patients. Additionally, there are currently no efficacious therapeutic agents to treat the muscle atrophy induced by the cancer. While several preclinical studies have investigated the molecular signals orchestrating cachexia, very little information exists pertaining to ovarian cancer and the associated cachexia. Work from our lab has recently demonstrated that the steroidal lactone Withaferin A (WFA) is capable of attenuating the atrophying effects of ovarian cancer in a preclinical mouse model. However, it remained to be determined whether WFA's effect was in response to its anti-tumorigenic properties, or if it was capable of targeting skeletal muscle directly. The purpose of this study was to uncover whether WFA was capable of regulating muscle mass under tumor-free and tumor-bearing conditions. Treatment with WFA led to an improvement in functional muscle strength and mass under tumor-bearing and naïve conditions. WFA and ovarian cancer were observed to act antagonistically upon critical skeletal muscle regulatory systems, notably myogenic progenitors and proteolytic degradation pathways. Our results demonstrated for the first time that, while WFA has anti-tumorigenic properties, it also exerts hypertrophying effects on skeletal muscle mass, suggesting that it could be an anti-cachectic agent in the settings of ovarian cancer.
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Affiliation(s)
- Alex R. Straughn
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Natia Q. Kelm
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
| | - Sham S. Kakar
- James Graham Brown Cancer Center, University of Louisville, Louisville, KY, United States
- Department of Physiology, University of Louisville, Louisville, KY, United States
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13
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Marola OJ, Syc-Mazurek SB, Howell GR, Libby RT. Endothelin 1-induced retinal ganglion cell death is largely mediated by JUN activation. Cell Death Dis 2020; 11:811. [PMID: 32980857 PMCID: PMC7519907 DOI: 10.1038/s41419-020-02990-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Revised: 08/26/2020] [Accepted: 08/27/2020] [Indexed: 01/02/2023]
Abstract
Glaucoma is a neurodegenerative disease characterized by loss of retinal ganglion cells (RGCs), the output neurons of the retina. Multiple lines of evidence show the endothelin (EDN, also known as ET) system is important in glaucomatous neurodegeneration. To date, the molecular mechanisms within RGCs driving EDN-induced RGC death have not been clarified. The pro-apoptotic transcription factor JUN (the canonical target of JNK signaling) and the endoplasmic reticulum stress effector and transcription factor DNA damage inducible transcript 3 (DDIT3, also known as CHOP) have been shown to act downstream of EDN receptors. Previous studies demonstrated that JUN and DDIT3 were important regulators of RGC death after glaucoma-relevant injures. Here, we characterized EDN insult in vivo and investigated the role of JUN and DDIT3 in EDN-induced RGC death. To accomplish this, EDN1 ligand was intravitreally injected into the eyes of wildtype, Six3-cre+Junfl/fl (Jun-/-), Ddit3 null (Ddit3-/-), and Ddit3-/-Jun-/- mice. Intravitreal EDN1 was sufficient to drive RGC death in vivo. EDN1 insult caused JUN activation in RGCs, and deletion of Jun from the neural retina attenuated RGC death after EDN insult. However, deletion of Ddit3 did not confer significant protection to RGCs after EDN1 insult. These results indicate that EDN caused RGC death via a JUN-dependent mechanism. In addition, EDN signaling is known to elicit potent vasoconstriction. JUN signaling was shown to drive neuronal death after ischemic insult. Therefore, the effects of intravitreal EDN1 on retinal vessel diameter and hypoxia were explored. Intravitreal EDN1 caused transient retinal vasoconstriction and regions of RGC and Müller glia hypoxia. Thus, it remains a possibility that EDN elicits a hypoxic insult to RGCs, causing apoptosis via JNK-JUN signaling. The importance of EDN-induced vasoconstriction and hypoxia in causing RGC death after EDN insult and in models of glaucoma requires further investigation.
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Affiliation(s)
- Olivia J. Marola
- grid.412750.50000 0004 1936 9166Department of Ophthalmology, Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY USA ,grid.412750.50000 0004 1936 9166Cell Biology of Disease Graduate Program, University of Rochester Medical Center, Rochester, NY USA ,grid.16416.340000 0004 1936 9174The Center for Visual Sciences, University of Rochester, Rochester, NY USA
| | - Stephanie B. Syc-Mazurek
- grid.412750.50000 0004 1936 9166Department of Ophthalmology, Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY USA ,grid.412750.50000 0004 1936 9166Medical Scientist Training Program, University of Rochester Medical Center, Rochester, NY USA
| | - Gareth R. Howell
- grid.249880.f0000 0004 0374 0039The Jackson Laboratory, 600 Main Street, Bar Harbor, ME USA
| | - Richard T. Libby
- grid.412750.50000 0004 1936 9166Department of Ophthalmology, Flaum Eye Institute, University of Rochester Medical Center, Rochester, NY USA ,grid.16416.340000 0004 1936 9174The Center for Visual Sciences, University of Rochester, Rochester, NY USA ,grid.412750.50000 0004 1936 9166Department of Biomedical Genetics, University of Rochester Medical Center, Rochester, NY USA
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14
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Li Z, Tang X, Zhu L, Qi X, Cao G, Lu G. Cytotoxic Screening and Transcriptomics Reveal Insights into the Molecular Mechanisms of Trihexyl Phosphate-Triggered Hepatotoxicity. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:11464-11475. [PMID: 32841022 DOI: 10.1021/acs.est.0c03824] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Mounting evidence shows that organophosphate flame retardants (OPFRs), especially aryl- and halogenated-OPFRs, exert various adverse health effects on living organisms. This study evaluated the hepatotoxic effect of trihexyl phosphate (THP) as a long-chain alkyl-OPFR on human hepatocyte cells (LO2) and mouse hepatocyte cells (AML12) by performing screening of cytotoxicity in vitro. In combination with transcriptomic analysis, toxicological mechanisms in vitro were further investigated. Results showed that THP triggered hepatotoxicity in vitro by altering four signaling pathways: endoplasmic reticulum (ER) stress, apoptosis, cell cycle, and the glycolysis signaling pathway. Exposure of LO2 and AML12 liver cells to THP (25 μg/mL) significantly induced ER stress-mediated apoptosis and cell cycle arrest. Meanwhile, downregulation of glycolysis caused the blockage of energy metabolism. Furthermore, the high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (HPLC-Q-TOF-MS/MS) revealed that much of THP was absorbed into the cells and displayed stability in the two liver cell lines. In vivo assays using a mouse model demonstrated that exposure to THP at 400 mg/kg induced the ballooning degeneration of hepatocytes in liver tissue, whereas exposure to THP at 800 mg/kg caused acute liver injury with high alanine aminotransferase levels. This study provides novel insights into the impact of THP on hepatotoxicity in vitro and in vivo and uncovers the underlying toxicological mechanisms, which may serve as a guide for further ecological risk assessment and reasonable application of alkyl-OPFRs.
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Affiliation(s)
- Zhenhua Li
- The First Affiliated Hospital, Biomedical Translational Research Institute and School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Xin Tang
- The First Affiliated Hospital, Biomedical Translational Research Institute and School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Lingfei Zhu
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Xiaojie Qi
- The First Affiliated Hospital, Biomedical Translational Research Institute and School of Pharmacy, Jinan University, Guangzhou 510632, China
| | - Gang Cao
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
| | - Gang Lu
- School of Environment, Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, China
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15
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Tezel G. A broad perspective on the molecular regulation of retinal ganglion cell degeneration in glaucoma. PROGRESS IN BRAIN RESEARCH 2020; 256:49-77. [PMID: 32958215 DOI: 10.1016/bs.pbr.2020.05.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Glaucoma is a complex neurodegenerative disease involving RGC axons, somas, and synapses at dendrites and axon terminals. Recent research advancements in the field have revealed a bigger picture of glaucomatous neurodegeneration that encompasses multiple stressors, multiple injury sites, multiple cell types, and multiple signaling pathways for asynchronous degeneration of RGCs during a chronic disease period. Optic nerve head is commonly viewed as the critical site of injury in glaucoma, where early injurious insults initiate distal and proximal signaling for axonal and somatic degeneration. Despite compartmentalized processes for degeneration of RGC axons and somas, there are intricate interactions between the two compartments and mechanistic overlaps between the molecular pathways that mediate degeneration in axonal and somatic compartments. This review summarizes the recent progress in the molecular understanding of RGC degeneration in glaucoma and highlights various etiological paths with biomechanical, metabolic, oxidative, and inflammatory components. Through this growing body of knowledge, the glaucoma community moves closer toward causative treatment of this blinding disease.
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Affiliation(s)
- Gülgün Tezel
- Department of Ophthalmology, Vagelos College of Physicians and Surgeons, Columbia University, Edward S. Harkness Eye Institute, New York, NY, United States.
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16
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Gorbatyuk MS, Starr CR, Gorbatyuk OS. Endoplasmic reticulum stress: New insights into the pathogenesis and treatment of retinal degenerative diseases. Prog Retin Eye Res 2020; 79:100860. [PMID: 32272207 DOI: 10.1016/j.preteyeres.2020.100860] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2019] [Revised: 03/08/2020] [Accepted: 03/17/2020] [Indexed: 12/13/2022]
Abstract
Physiological equilibrium in the retina depends on coordinated work between rod and cone photoreceptors and can be compromised by the expression of mutant proteins leading to inherited retinal degeneration (IRD). IRD is a diverse group of retinal dystrophies with multifaceted molecular mechanisms that are not fully understood. In this review, we focus on the contribution of chronically activated unfolded protein response (UPR) to inherited retinal pathogenesis, placing special emphasis on studies employing genetically modified animal models. As constitutively active UPR in degenerating retinas may activate pro-apoptotic programs associated with oxidative stress, pro-inflammatory signaling, dysfunctional autophagy, free cytosolic Ca2+ overload, and altered protein synthesis rate in the retina, we focus on the regulatory mechanisms of translational attenuation and approaches to overcoming translational attenuation in degenerating retinas. We also discuss current research on the role of the UPR mediator PERK and its downstream targets in degenerating retinas and highlight the therapeutic benefits of reprogramming PERK signaling in preclinical animal models of IRD. Finally, we describe pharmacological approaches targeting UPR in ocular diseases and consider their potential applications to IRD.
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Affiliation(s)
- Marina S Gorbatyuk
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA.
| | - Christopher R Starr
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA
| | - Oleg S Gorbatyuk
- The University of Alabama at Birmingham, Department of Optometry and Vision Science, School of Optometry, USA
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17
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Ambroxol Improves Neuronal Survival and Reduces White Matter Damage through Suppressing Endoplasmic Reticulum Stress in Microglia after Intracerebral Hemorrhage. BIOMED RESEARCH INTERNATIONAL 2020; 2020:8131286. [PMID: 32309438 PMCID: PMC7142346 DOI: 10.1155/2020/8131286] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/08/2020] [Revised: 02/23/2020] [Accepted: 02/28/2020] [Indexed: 12/31/2022]
Abstract
Intracerebral hemorrhage (ICH) has been becoming a serious public health problem. Pneumonia, occurring in 43% of all ICH patients, is a common complication heavily influencing outcome and accounting for more than 1/3 of the overall mortality in patients with ICH. Ambroxol may be an effective additional treatment for ICH patients with pneumonia. But its effect and potential mechanism on functional recovery post-ICH still remain elusive. In the present study, the results indicated that 35 mg/kg and 70 mg/kg ambroxol facilitated neuronal survival and reduced white matter fiber bundle damage due to mitigating microglial activation and reducing proinflammatory cytokine accumulation in mice with ICH. The possible mechanism might be due to suppressing endoplasmic reticulum stress involving the IRE1α/TRAF2 signaling pathway, which paves a new path for the treatment of ICH and opens a new window for the use of ambroxol in clinical practice.
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