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Boya P, Kaarniranta K, Handa JT, Sinha D. Lysosomes in retinal health and disease. Trends Neurosci 2023; 46:1067-1082. [PMID: 37848361 PMCID: PMC10842632 DOI: 10.1016/j.tins.2023.09.006] [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: 06/18/2023] [Revised: 09/06/2023] [Accepted: 09/24/2023] [Indexed: 10/19/2023]
Abstract
Lysosomes play crucial roles in various cellular processes - including endocytosis, phagocytosis, and autophagy - which are vital for maintaining retinal health. Moreover, these organelles serve as environmental sensors and act as central hubs for multiple signaling pathways. Through communication with other cellular components, such as mitochondria, lysosomes orchestrate the cytoprotective response essential for preserving cellular homeostasis. This coordination is particularly critical in the retina, given its high metabolic rate and susceptibility to photo-oxidative stress. Consequently, impaired lysosomal function and dysregulated communication between lysosomes and other organelles contribute significantly to the pathobiology of major retinal degenerative diseases. This review explores the pivotal role of lysosomes in retinal cells and their involvement in retinal degenerative diseases.
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Affiliation(s)
- Patricia Boya
- Department of Neuroscience, University of Fribourg, Fribourg, Switzerland
| | - Kai Kaarniranta
- Department of Ophthalmology, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland; Department of Molecular Genetics, University of Lodz, Lodz, Poland
| | - James T Handa
- The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Debasish Sinha
- The Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA; Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
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2
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Dixon A, Shim MS, Nettesheim A, Coyne A, Su CC, Gong H, Liton PB. Autophagy deficiency protects against ocular hypertension and neurodegeneration in experimental and spontanous glaucoma mouse models. Cell Death Dis 2023; 14:554. [PMID: 37620383 PMCID: PMC10449899 DOI: 10.1038/s41419-023-06086-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 08/02/2023] [Accepted: 08/17/2023] [Indexed: 08/26/2023]
Abstract
Glaucoma is a group of diseases that leads to chronic degeneration of retinal ganglion cell (RGC) axons and progressive loss of RGCs, resulting in vision loss. While aging and elevated intraocular pressure (IOP) have been identified as the main contributing factors to glaucoma, the molecular mechanisms and signaling pathways triggering RGC death and axonal degeneration are not fully understood. Previous studies in our laboratory found that overactivation of autophagy in DBA/2J::GFP-LC3 mice led to RGC death and optic nerve degeneration with glaucomatous IOP elevation. We found similar findings in aging GFP-LC3 mice subjected to chronic IOP elevation. Here, we further investigated the impact of autophagy deficiency on autophagy-deficient DBA/2J-Atg4bko and DBA/2J-Atg4b+/- mice, generated in our laboratory via CRISPR/Cas9 technology; as well as in Atg4bko mice subjected to the experimental TGFβ2 chronic ocular hypertensive model. Our data shows that, in contrast to DBA/2J and DBA/2J-Atg4b+/- littermates, DBA/2J-Atg4bko mice do not develop glaucomatous IOP elevation. Atg4b deficiency also protected against glaucomatous IOP elevation in the experimental TGFβ2 chronic ocular hypertensive model. Atg4 deletion did not compromise RGC or optic nerve survival in Atg4bko mice. Moreover, our results indicate a protective role of autophagy deficiency against RGC death and ON atrophy in the hypertensive DBA/2J-Atg4b+/- mice. Together, our data suggests a pathogenic role of autophagy activation in ocular hypertension and glaucoma.
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Affiliation(s)
- Angela Dixon
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA
| | - Myoung Sup Shim
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA
| | - April Nettesheim
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA
| | - Aislyn Coyne
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA
| | - Chien-Chia Su
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA
| | - Haiyan Gong
- Department of Ophthalmology, Boston University School of Medicine, Boston, MA, 02118, USA
| | - Paloma B Liton
- Department of Ophthalmology & Pathology, Duke University, Durham, NC, 27705, USA.
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3
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Chakraborthy M, Rao A. A Feedback Loop between TGF-β1 and ATG5 Mediated by miR-122-5p Regulates Fibrosis and EMT in Human Trabecular Meshwork Cells. Curr Issues Mol Biol 2023; 45:2381-2392. [PMID: 36975524 PMCID: PMC10047315 DOI: 10.3390/cimb45030154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/11/2023] [Accepted: 02/20/2023] [Indexed: 03/16/2023] Open
Abstract
Autophagy is a cell’s evolutionary conserved process for degrading and recycling cellular proteins and removing damaged organelles. There has been an increasing interest in identifying the basic cellular mechanism of autophagy and its implications in health and illness during the last decade. Many proteinopathies such as Alzheimer’s and Huntington’s disease are reported to be associated with impaired autophagy. The functional significance of autophagy in exfoliation syndrome/exfoliation glaucoma (XFS/XFG), remains unknown though it is presumed to be impaired autophagy to be responsible for the aggregopathy characteristic of this disease. In the current study we have shown that autophagy or ATG5 is enhanced in response to TGF-β1 in human trabecular meshwork (HTM) cells and TGF-β1 induced autophagy is necessary for increased expression of profibrotic proteins and epithelial to mesenchymal (EMT) through Smad3 that lead to aggregopathy. Inhibition of ATG5 by siRNA mediated knockdown reduced profibrotic and EMT markers and increased protein aggregates in the presence of TGF-β1 stimulation. The miR-122-5p, which was increased upon TGF exposure, was also reduced upon ATG5 inhibition. We thus conclude that TGF-β1 induces autophagy in primary HTM cells and a positive feedback loop exists between TGF-β1 and ATG5 that regulated TGF downstream effects mainly mediated by Smad3 signaling with miR-122-5p also playing a role.
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Affiliation(s)
- Munmun Chakraborthy
- Hyderabad Eye Research Foundation (HERF), L.V. Prasad Eye Institute, Bhubaneswar 751024, Odisha, India
- School of Biotechnology, KIIT University, Bhubaneswar 751024, Odisha, India
| | - Aparna Rao
- Hyderabad Eye Research Foundation (HERF), L.V. Prasad Eye Institute, Bhubaneswar 751024, Odisha, India
- School of Biotechnology, KIIT University, Bhubaneswar 751024, Odisha, India
- Correspondence:
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4
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Liton PB, Boesze-Battaglia K, Boulton ME, Boya P, Ferguson TA, Ganley IG, Kauppinnen A, Laurie GW, Mizushima N, Morishita H, Russo R, Sadda J, Shyam R, Sinha D, Thompson DA, Zacks DN. AUTOPHAGY IN THE EYE: FROM PHYSIOLOGY TO PATHOPHYSOLOGY. AUTOPHAGY REPORTS 2023; 2:2178996. [PMID: 37034386 PMCID: PMC10078619 DOI: 10.1080/27694127.2023.2178996] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 01/26/2023] [Indexed: 03/05/2023]
Abstract
Autophagy is a catabolic self-degradative pathway that promotes the degradation and recycling of intracellular material through the lysosomal compartment. Although first believed to function in conditions of nutritional stress, autophagy is emerging as a critical cellular pathway, involved in a variety of physiological and pathophysiological processes. Autophagy dysregulation is associated with an increasing number of diseases, including ocular diseases. On one hand, mutations in autophagy-related genes have been linked to cataracts, glaucoma, and corneal dystrophy; on the other hand, alterations in autophagy and lysosomal pathways are a common finding in essentially all diseases of the eye. Moreover, LC3-associated phagocytosis, a form of non-canonical autophagy, is critical in promoting visual cycle function. This review collects the latest understanding of autophagy in the context of the eye. We will review and discuss the respective roles of autophagy in the physiology and/or pathophysiology of each of the ocular tissues, its diurnal/circadian variation, as well as its involvement in diseases of the eye.
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Affiliation(s)
- Paloma B. Liton
- Departments of Ophthalmology & Pathology, Duke School of Medicine, Duke University, Durham, NC 27705, USA
| | - Kathleen Boesze-Battaglia
- Department of Basic and Translational Sciences, University of Pennsylvania, School of Dental Medicine, Philadelphia, PA 19104, USA
| | - Michael E. Boulton
- Department of Ophthalmology and Visual Sciences, University of Alabama at Birmingham (UAB), Birmingham, AL, USA
| | - Patricia Boya
- Department of Neuroscience and Movement Science. Faculty of Science and Medicine, University of Fribourg, 1700 Fribourg, Switzerland
| | - Thomas A. Ferguson
- Department of Ophthalmology and Visual Sciences, Washington University in St. Louis, St. Louis, MO 63110, USA
| | - Ian G. Ganley
- MRC Protein Phosphorylation and Ubiquitylation Unit, School of Life Sciences, University of Dundee, Dundee, DD1 5EH, UK
| | - Anu Kauppinnen
- Faculty of Health and Sciences, School of Pharmacy, University of Eastern Finland, 70210 Kuopio, Finland
| | - Gordon W. Laurie
- Departments of Cell Biology, Ophthalmology and Biomedical Engineering, University of Virginia, Charlottesville, VA 22908, USA
| | - Noboru Mizushima
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, 113-0033, Japan
| | - Hideaki Morishita
- Department of Biochemistry and Molecular Biology, Graduate School of Medicine, The University of Tokyo, 113-0033, Japan
- Department of Physiology, Juntendo University Graduate School of Medicine, Bunkyo-ku, Tokyo, 113-8421, Japan
| | - Rossella Russo
- Preclinical and Translational Pharmacology, Glaucoma Unit, Department of Pharmacy, Health and Nutritional Sciences, University of Calabria, 87036 Rende, Italy
| | - Jaya Sadda
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | | | - Debasish Sinha
- Department of Ophthalmology, Cell Biology, and Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
- Wilmer Eye Institute, The Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Debra A. Thompson
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
| | - David N. Zacks
- Department of Ophthalmology and Visual Sciences, Kellogg Eye Center, University of Michigan Medical School, Ann Arbor, MI, USA
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Irnaten M, O’Brien CJ. Calcium-Signalling in Human Glaucoma Lamina Cribrosa Myofibroblasts. Int J Mol Sci 2023; 24:ijms24021287. [PMID: 36674805 PMCID: PMC9862249 DOI: 10.3390/ijms24021287] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/20/2022] [Accepted: 01/01/2023] [Indexed: 01/11/2023] Open
Abstract
Glaucoma is one of the most common causes of treatable visual impairment in the developed world, affecting approximately 64 million people worldwide, some of whom will be bilaterally blind from irreversible optic nerve damage. The optic nerve head is a key site of damage in glaucoma where there is fibrosis of the connective tissue in the lamina cribrosa (LC) extracellular matrix. As a ubiquitous second messenger, calcium (Ca2+) can interact with various cellular proteins to regulate multiple physiological processes and contribute to a wide range of diseases, including cancer, fibrosis, and glaucoma. Our research has shown evidence of oxidative stress, mitochondrial dysfunction, an elevated expression of Ca2+ entry channels, Ca2+-dependent pumps and exchangers, and an abnormal rise in cytosolic Ca2+ in human glaucomatous LC fibroblast cells. We have evidence that this increase is dependent on Ca2+ entry channels located in the plasma membrane, and its release is from internal stores in the endoplasmic reticulum (ER), as well as from the mitochondria. Here, we summarize some of the molecular Ca2+-dependent mechanisms related to this abnormal Ca2+-signalling in human glaucoma LC cells, with a view toward identifying potential therapeutic targets for ongoing optic neuropathy.
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Adulla A, Patel U, Ashok A, Katiyar P, Kaulakis M, Kritikos AE, Pillai S, Lee H, Lindner E, Rhee DJ, Singh N. α-Synuclein modulates fibronectin expression in the trabecular meshwork independent of TGFβ2. Exp Eye Res 2023; 226:109351. [PMID: 36539052 PMCID: PMC10384565 DOI: 10.1016/j.exer.2022.109351] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 12/06/2022] [Accepted: 12/12/2022] [Indexed: 12/23/2022]
Abstract
α-Synuclein (α-Syn) is implicated in Parkinson's disease (PD), a neuromotor disorder with prominent visual symptoms. The underlying cause of motor dysfunction has been studied extensively, and is attributed to the death of dopaminergic neurons mediated in part by intracellular aggregation of α-Syn. The cause of visual symptoms, however, is less clear. Neuroretinal degeneration due to the presence of aggregated α-Syn has been reported, but the evidence is controversial. Other symptoms including those arising from primary open angle glaucoma (POAG) are believed to be the side-effects of medications prescribed for PD. Here, we explored the alternative hypothesis that dysfunction of α-Syn in the anterior eye alters the interaction between the actin cytoskeleton of trabecular meshwork (TM) cells with the extracellular matrix (ECM), impairing their ability to respond to physiological changes in intraocular pressure (IOP). A similar dysfunction in neurons is responsible for impaired neuritogenesis, a characteristic feature of PD. Using cadaveric human and bovine TM tissue and primary human TM cells as models, we report two main observations: 1) α-Syn is expressed in human and bovine TM cells, and significant amounts of monomeric and oligomeric α-Syn are present in the AH, and 2) primary human TM cells and human and bovine TM tissue endocytose extracellular recombinant monomeric and oligomeric α-Syn via the prion protein (PrPC), and upregulate fibronectin (FN) and α-smooth muscle actin (α-SMA), fibrogenic proteins implicated in POAG. Transforming growth factor β2 (TGFβ2), a fibrogenic cytokine implicated in ∼50% cases of POAG, is also increased, and so is RhoA-associated coiled-coil-containing protein kinase 1 (ROCK-1). However, silencing of α-Syn in primary human TM cells reduces FN, α-SMA, and ROCK-1 in the absence or presence of over-expressed active TGFβ2, suggesting modulation of FN and ROCK-1 independent of, or upstream of TGFβ2. These observations suggest that extracellular α-Syn modulates ECM proteins in the TM independently or via PrPC by activating the RhoA-ROCK pathway. These observations reveal a novel function of α-Syn in the anterior eye, and offer new therapeutic options.
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Affiliation(s)
- Anika Adulla
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Urvi Patel
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Ajay Ashok
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Priya Katiyar
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Mare Kaulakis
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Alexander E Kritikos
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Sachin Pillai
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - HyunPin Lee
- Departments of Ophthalmology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Ewald Lindner
- Department of Ophthalmology, Medical University of Graz, Auenbruggerplatz 4, 8036, Graz, Austria
| | - Douglas J Rhee
- Departments of Ophthalmology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA
| | - Neena Singh
- Departments of Pathology, School of Medicine, Case Western Reserve University, Cleveland, OH, 44106, USA.
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7
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Soundararajan A, Wang T, Sundararajan R, Wijeratne A, Mosley A, Harvey FC, Bhattacharya S, Pattabiraman PP. Multiomics analysis reveals the mechanical stress-dependent changes in trabecular meshwork cytoskeletal-extracellular matrix interactions. Front Cell Dev Biol 2022; 10:874828. [PMID: 36176278 PMCID: PMC9513235 DOI: 10.3389/fcell.2022.874828] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2022] [Accepted: 08/12/2022] [Indexed: 11/29/2022] Open
Abstract
Trabecular meshwork (TM) tissue is subjected to constant mechanical stress due to the ocular pulse created by the cardiac cycle. This brings about alterations in the membrane lipids and associated cell–cell adhesion and cell–extracellular matrix (ECM) interactions, triggering intracellular signaling responses to counter mechanical insults. A loss of such response can lead to elevated intraocular pressure (IOP), a major risk factor for primary open-angle glaucoma. This study is aimed to understand the changes in signaling responses by TM subjected to mechanical stretch. We utilized multiomics to perform an unbiased mRNA sequencing to identify changes in transcripts, mass spectrometry- (MS-) based quantitative proteomics for protein changes, and multiple reaction monitoring (MRM) profiling-based MS and high-performance liquid chromatography (HPLC-) based MS to characterize the lipid changes. We performed pathway analysis to obtain an integrated map of TM response to mechanical stretch. The human TM cells subjected to mechanical stretch demonstrated an upregulation of protein quality control, oxidative damage response, pro-autophagic signal, induction of anti-apoptotic, and survival signaling. We propose that mechanical stretch-induced lipid signaling via increased ceramide and sphingomyelin potentially contributes to increased TM stiffness through actin-cytoskeleton reorganization and profibrotic response. Interestingly, increased phospholipids and diacylglycerol due to mechanical stretch potentially enable cell membrane remodeling and changes in signaling pathways to alter cellular contractility. Overall, we propose the mechanistic interplay of macromolecules to bring about a concerted cellular response in TM cells to achieve mechanotransduction and IOP regulation when TM cells undergo mechanical stretch.
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Affiliation(s)
- Avinash Soundararajan
- Department of Ophthalmology, Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Ting Wang
- Department of Ophthalmology, Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, United States
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Rekha Sundararajan
- Department of Ophthalmology, Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Aruna Wijeratne
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
- Center for Proteome Analysis, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Amber Mosley
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
- Center for Proteome Analysis, Indiana University School of Medicine, Indianapolis, IN, United States
- Center for Computational Biology and Bioinformatics, Indiana University School of Medicine, Indianapolis, IN, United States
| | - Faith Christine Harvey
- Bascom Palmer Eye Institute, Miller School of Medicine at University of Miami, Miami, FL, United States
- Miami Integrative Metabolomics Research Center, Miami, FL, United States
| | - Sanjoy Bhattacharya
- Bascom Palmer Eye Institute, Miller School of Medicine at University of Miami, Miami, FL, United States
- Miami Integrative Metabolomics Research Center, Miami, FL, United States
| | - Padmanabhan Paranji Pattabiraman
- Department of Ophthalmology, Glick Eye Institute, Indiana University School of Medicine, Indianapolis, IN, United States
- Stark Neuroscience Research Institute, Indiana University School of Medicine, Indianapolis, IN, United States
- Department of Biochemistry and Molecular Biology, Indiana University School of Medicine, Indianapolis, IN, United States
- *Correspondence: Padmanabhan Paranji Pattabiraman,
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8
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Shim MS, Liton PB. The physiological and pathophysiological roles of the autophagy lysosomal system in the conventional aqueous humor outflow pathway: More than cellular clean up. Prog Retin Eye Res 2022; 90:101064. [PMID: 35370083 PMCID: PMC9464695 DOI: 10.1016/j.preteyeres.2022.101064] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 03/09/2022] [Accepted: 03/25/2022] [Indexed: 10/18/2022]
Abstract
During the last few years, the autophagy lysosomal system is emerging as a central cellular pathway with roles in survival, acting as a housekeeper and stress response mechanism. Studies by our and other labs suggest that autophagy might play an essential role in maintaining aqueous humor outflow homeostasis, and that malfunction of autophagy in outflow pathway cells might predispose to ocular hypertension and glaucoma pathogenesis. In this review, we will collect the current knowledge and discuss the molecular mechanisms by which autophagy does or might regulate normal outflow pathway tissue function, and its response to different types of stressors (oxidative stress and mechanical stress). We will also discuss novel roles of autophagy and lysosomal enzymes in modulation of TGFβ signaling and ECM remodeling, and the link between dysregulated autophagy and cellular senescence. We will examine what we have learnt, using pre-clinical animal models about how dysregulated autophagy can contribute to disease and apply that to the current status of autophagy in human glaucoma. Finally, we will consider and discuss the challenges and the potential of autophagy as a therapeutic target for the treatment of ocular hypertension and glaucoma.
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Affiliation(s)
- Myoung Sup Shim
- Duke University, Department of Ophthalmology, Durham, NC, 27705, USA
| | - Paloma B Liton
- Duke University, Department of Ophthalmology, Durham, NC, 27705, USA.
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9
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Fuellen G, Jünemann A. Gene Expression Data for Investigating Glaucoma Treatment Options and Pharmacology in the Anterior Segment, State-of-the-Art and Future Directions. Front Neurosci 2022; 16:912043. [PMID: 35757536 PMCID: PMC9213806 DOI: 10.3389/fnins.2022.912043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 05/20/2022] [Indexed: 11/30/2022] Open
Abstract
Glaucoma treatment options as well as its etiology are far from understood. Gene expression (transcriptomics) data of the anterior segment of the eye can help by elucidating the molecular-mechanistic underpinnings, and we present an up-to-date description and discussion of what gene expression data are publicly available, and for which purposes these can be used. We feature the few resources covering all segments of the eye, and we then specifically focus on the anterior segment, and provide an extensive list of the Gene Expression Omnibus data that may be useful. We also feature single-cell data of relevance, particularly three datasets from tissues of relevance to aqueous humor outflow. We describe how the data have been used by researchers, by following up resource citations and data re-analyses. We discuss datasets and analyses pertaining to fibrosis following glaucoma surgery, and to glaucoma resulting from the use of steroids. We conclude by pointing out the current lack and underutilization of ocular gene expression data, and how the state of the art is expected to improve in the future.
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Affiliation(s)
- Georg Fuellen
- Institute for Biostatistics and Informatics in Medicine and Aging Research, Rostock University Medical Center, Rostock, Germany
| | - Anselm Jünemann
- Institute for Biostatistics and Informatics in Medicine and Aging Research, Rostock University Medical Center, Rostock, Germany
- Department of Ophthalmology, Rostock University Medical Center, Rostock, Germany
- Department of General Ophthalmology and Pediatric Ophthalmology Service, Medical University of Lublin, Lublin, Poland
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10
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Sundberg CA, Lakk M, Paul S, Figueroa KP, Scoles DR, Pulst SM, Križaj D. The RNA-binding protein and stress granule component ATAXIN-2 is expressed in mouse and human tissues associated with glaucoma pathogenesis. J Comp Neurol 2022; 530:537-552. [PMID: 34350994 PMCID: PMC8716417 DOI: 10.1002/cne.25228] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Accepted: 07/06/2021] [Indexed: 02/03/2023]
Abstract
Polyglutamine repeat expansions in the Ataxin-2 (ATXN2) gene were first implicated in Spinocerebellar Ataxia Type 2, a disease associated with degeneration of motor neurons and Purkinje cells. Recent studies linked single nucleotide polymorphisms in the gene to elevated intraocular pressure in primary open angle glaucoma (POAG); yet, the localization of ATXN2 across glaucoma-relevant tissues of the vertebrate eye has not been thoroughly examined. This study characterizes ATXN2 expression in the mouse and human retina, and anterior eye, using an antibody validated in ATXN2-/- retinas. ATXN2-ir was localized to cytosolic sub compartments in retinal ganglion cell (RGC) somata and proximal dendrites in addition to GABAergic, glycinergic, and cholinergic amacrine cells in the inner plexiform layer (IPL) and displaced amacrine cells. Human, but not mouse retinas showed modest immunolabeling of bipolar cells. ATXN2 immunofluorescence was prominent in the trabecular meshwork and pigmented and nonpigmented cells of the ciliary body, with analyses of primary human trabecular meshwork cells confirming the finding. The expression of ATXN2 in key POAG-relevant ocular tissues supports the potential role in autophagy and stress granule formation in response to ocular hypertension.
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Affiliation(s)
- Chad A. Sundberg
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, Utah, USA
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Monika Lakk
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, Utah, USA
| | - Sharan Paul
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Karla P. Figueroa
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Daniel R. Scoles
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - Stefan M. Pulst
- Department of Neurology, University of Utah, Salt Lake City, Utah, USA
| | - David Križaj
- Department of Ophthalmology & Visual Sciences, University of Utah, Salt Lake City, Utah, USA
- Department of Bioengineering, University of Utah, Salt Lake City, Utah, USA
- Department of Neurobiology & Anatomy, University of Utah, Salt Lake City, Utah, USA
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11
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Pavel M, Tanasa R, Park SJ, Rubinsztein DC. The complexity of biological control systems: An autophagy case study. Bioessays 2022; 44:e2100224. [PMID: 35032045 DOI: 10.1002/bies.202100224] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2021] [Revised: 12/07/2021] [Accepted: 01/04/2022] [Indexed: 01/18/2023]
Abstract
Autophagy and YAP1-WWTR1/TAZ signalling are tightly linked in a complex control system of forward and feedback pathways which determine different cellular outcomes in differing cell types at different time-points after perturbations. Here we extend our previous experimental and modelling approaches to consider two possibilities. First, we have performed additional mathematical modelling to explore how the autophagy-YAP1 crosstalk may be controlled by posttranslational modifications of components of the pathways. Second, since analogous contrasting results have also been reported for autophagy as a regulator of other transduction pathways engaged in tumorigenesis (Wnt/β-catenin, TGF-β/Smads, NF-kB or XIAP/cIAPs), we have considered if such discrepancies may be explicable through situations involving competing pathways and feedback loops in different cell types, analogous to the autophagy-YAP/TAZ situation. Since distinct posttranslational modifications dominate those pathways in distinct cells, these need to be understood to enable appropriate cell type-specific therapeutic strategies for cancers and other diseases.
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Affiliation(s)
- Mariana Pavel
- Department of Immunology, Grigore T. Popa University of Medicine and Pharmacy of Iasi, Iasi, Romania
| | - Radu Tanasa
- Department of Physics, Alexandru Ioan Cuza University of Iasi, Iasi, Romania
| | - So Jung Park
- Department of Medical Genetics, Cambridge Biomedical Campus, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Cambridge, UK.,Cambridge Biomedical Campus, Cambridge Biomedical Campus, UK Dementia Research Institute, Cambridge, UK
| | - David C Rubinsztein
- Department of Medical Genetics, Cambridge Biomedical Campus, Cambridge Institute for Medical Research, Wellcome Trust/MRC Building, Cambridge, UK.,Cambridge Biomedical Campus, Cambridge Biomedical Campus, UK Dementia Research Institute, Cambridge, UK
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12
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Guo J, Liu H, Fu L. MicroRNA-124 ameliorates autophagic dysregulation in glaucoma via regulation of P2X7-mediated Akt/mTOR signaling. Cutan Ocul Toxicol 2021; 41:43-48. [PMID: 34844494 DOI: 10.1080/15569527.2021.2003378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Glaucoma is a neurodegenerative disease that leads to irrevocable blindness. In glaucoma, even though axonal damage and function deficit culminates in retinal ganglion cell (RGC) degeneration, our knowledge on the autophagic mechanisms and the role of specific microRNAs is still limited. In this study, we investigated the role of microRNA-124 (MiR-124) in surgically induced glaucomatous neurodegeneration using a mouse model. Animals were segregated into four cohorts of 10 each: (i) sham-operated (n = 10); (ii) surgically induced glaucoma (SIG; n = 10); (iii) SIG + miR-124 mimic; (iv) SIG + miR-NC. Chronic elevation of intraocular pressure (IOP) is a critical risk factor for glaucoma. In our study, chronically elevated IOP caused anterograde axonal transport (AAT) defect, increased the autophagic activity (manifested by significantly (p < 0.05) increased LC3-II/LC3-I ratio, beclin-1 and Atg7 protein expressions) and also downmodulated the protein expression of p-Akt and p-mTOR, mediated by the purinergic P2 receptor subtype 7 (P2X7) upmodulation-leading to retinal degeneration. However, administration of miR-124 mimic improved the retinal integrity and function, as indicated by the improved AAT function, normalized the autophagic dysfunction, modulated the protein expression of P2X7-mediated p-Akt and p-mTOR. Hence, we propose that development of miR-124-based advanced therapies might be a potential avenue in the treatment of glaucomatous neurodegeneration.
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Affiliation(s)
- Jun Guo
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
| | - Haojie Liu
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
| | - Lin Fu
- Department of Ophthalmology, Zhongshan Hospital Affiliated with Dalian University, Dalian, China
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Primary cilia and the reciprocal activation of AKT and SMAD2/3 regulate stretch-induced autophagy in trabecular meshwork cells. Proc Natl Acad Sci U S A 2021; 118:2021942118. [PMID: 33753495 DOI: 10.1073/pnas.2021942118] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Activation of autophagy is one of the responses elicited by high intraocular pressure (IOP) and mechanical stretch in trabecular meshwork (TM) cells. However, the mechanosensor and the molecular mechanisms by which autophagy is induced by mechanical stretch in these or other cell types is largely unknown. Here, we have investigated the mechanosensor and downstream signaling pathway that regulate cyclic mechanical stretch (CMS)-induced autophagy in TM cells. We report that primary cilia act as a mechanosensor for CMS-induced autophagy and identified a cross-regulatory talk between AKT1 and noncanonical SMAD2/3 signaling as critical components of primary cilia-mediated activation of autophagy by mechanical stretch. Furthermore, we demonstrated the physiological significance of our findings in ex vivo perfused eyes. Removal of primary cilia disrupted the homeostatic IOP compensatory response and prevented the increase in LC3-II protein levels in response to elevated pressure challenge, strongly supporting a role of primary cilia-mediated autophagy in regulating IOP homeostasis.
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Immune responses to injury and their links to eye disease. Transl Res 2021; 236:52-71. [PMID: 34051364 PMCID: PMC8380715 DOI: 10.1016/j.trsl.2021.05.005] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/30/2021] [Revised: 05/12/2021] [Accepted: 05/24/2021] [Indexed: 12/31/2022]
Abstract
The eye is regarded as an immune privileged site. Since the presence of a vasculature would impair vision, the vasculature of the eye is located outside of the central light path. As a result, many regions of the eye evolved mechanisms to deliver immune cells to sites of dysgenesis, injury, or in response to the many age-related pathologies. While the purpose of these immune responses is reparative or protective, cytokines released by immune cells compromise visual acuity by inducing inflammation and fibrosis. The response to traumatic or pathological injury is distinct in different regions of the eye. Age-related diseases impact both the anterior and posterior segment and lead to reduced quality of life and blindness. Here we focus attention on the role that inflammation and fibrosis play in the progression of age-related pathologies of the cornea and the lens as well as in glaucoma, the formation of epiretinal membranes, and in proliferative vitreoretinopathy.
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Key Words
- 2ryERM
- A T-helper cell that expresses high levels of IL-17 which can suppress T-regulatory cell function
- A cytokine expressed early during inflammation that attracts neutrophils
- A cytokine expressed early during inflammation that attracts neutrophils, sometimes referred to as monocyte chemoattractant protein-1 (MCP-1))
- A mouse model that lacks functional T and B cells and used to study the immune response
- A pigmented mouse strain used for research and known to mount a primarily Th1 response to infection
- A protein encoded by the ADGRE1 gene that, in mice, is expressed primarily on macrophages
- A strain of pigmented mice used in glaucoma research
- ACAID
- APCs
- ASC
- An albino mouse strain used for research and known to mount a primarily Th2 response to infection
- Antigen Presenting Cells, this class includes dendritic cells and monocytes
- BALB/c
- BM
- C57BL6
- CCL2
- CD45
- CNS
- CXCL1
- Central Nervous System
- Cluster of differentiation 45 antigen
- DAMPs
- DBA/2J
- EBM
- ECM
- EMT
- ERM
- Epithelial Basement Membrane
- F4/80
- FGF2
- HA =hyaluronic acid
- HSK
- HSP
- HSPGs
- HSV
- ICN
- IL-20
- IL6
- ILM
- IOP
- Inner (or internal) limiting membrane
- Interleukin 6
- Interleukin-20
- MAGP1
- MHC-II
- Major histocompatibility complex type II, a class of MHC proteins typically found only on APCs
- Microfibril-associated glycoprotein 1
- N-cad
- N-cadherin
- NEI
- NK
- National Eye Institute
- Natural killer T cells
- PCO
- PDGF
- PDR
- PVD
- PVR
- Platelet derived growth factor
- Posterior capsular opacification
- RGC
- RPE
- RRD
- Rag1-/-
- Retinal ganglion cells
- Retinal pigment epithelial cells
- SMAD
- Sons of Mothers Against Decapentaplegic, SMADs are a class of molecules that mediate TGF and bone morphogenetic protein signaling
- T-helper cell 1 response, proinflammatory adaptive response involving interferon gamma and associated with autoimmunity
- T-helper cell 2 response involving IgE and interleukins 4,5, and 13, also induces the anti-inflammatory interleukin 10 family cytokines
- T-regulatory cell
- TG
- TGF1
- TM
- TNF
- Th1
- Th17
- Th2
- Transforming growth factor 1
- Treg
- Tumor necrosis factor a cytokine produced during inflammation
- VEGF
- Vascular endothelial growth factor
- WHO
- World Health Organization
- anterior chamber immune deviation
- anterior subcapsular cataracts
- basement membrane
- damage-associated molecular patterns
- epiretinal membrane
- epiretinal membrane secondary to disease pathology
- epithelial-mesenchymal transition
- extracellular matrix
- fibroblast growth factor 2, also referred to as basic FGF
- heat shock protein
- heparan sulfate proteoglycans
- herpes simplex virus
- herpes stromal keratitis
- iERM
- idiopathic epiretinal membrane
- intraepithelial corneal nerves
- intraocular pressure
- mTOR
- mechanistic target of rapamycin, a protein kinase encoded by the MTOR genes that regulates a variety of signal transduction events including cell growth, autophagy and actin cytoskeleton
- posterior vitreous detachment
- proliferative diabetic retinopathy
- proliferative vitreoretinopathy
- rhegmatogenous (rupture, tear) retinal detachment
- trabecular meshwork
- trigeminal ganglion
- αSMA
- α−Smooth muscle actin, a class of actin expressed in mesenchymal cells
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Sbardella D, Tundo GR, Coletta M, Manni G, Oddone F. Dexamethasone Downregulates Autophagy through Accelerated Turn-Over of the Ulk-1 Complex in a Trabecular Meshwork Cells Strain: Insights on Steroid-Induced Glaucoma Pathogenesis. Int J Mol Sci 2021; 22:ijms22115891. [PMID: 34072647 PMCID: PMC8198647 DOI: 10.3390/ijms22115891] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2021] [Revised: 05/20/2021] [Accepted: 05/24/2021] [Indexed: 12/16/2022] Open
Abstract
Steroid-induced glaucoma is a severe pathological condition, sustained by a rapidly progressive increase in intraocular pressure (IOP), which is diagnosed in a subset of subjects who adhere to a glucocorticoid (GC)-based therapy. Molecular and clinical studies suggest that either natural or synthetic GCs induce a severe metabolic dysregulation of Trabecular Meshwork Cells (TMCs), an endothelial-derived histotype with phagocytic and secretive functions which lay at the iridocorneal angle in the anterior segment of the eye. Since TMCs physiologically regulate the composition and architecture of trabecular meshwork (TM), which is the main outflow pathway of aqueous humor, a fluid which shapes the eye globe and nourishes the lining cell types, GCs are supposed to trigger a pathological remodeling of the TM, inducing an IOP increase and retina mechanical compression. The metabolic dysregulation of TMCs induced by GCs exposure has never been characterized at the molecular detail. Herein, we report that, upon dexamethasone exposure, a TMCs strain develops a marked inhibition of the autophagosome biogenesis pathway through an enhanced turnover of two members of the Ulk-1 complex, the main platform for autophagy induction, through the Ubiquitin Proteasome System (UPS).
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Affiliation(s)
- Diego Sbardella
- IRCCS-Fondazione Bietti, 00198 Rome, Italy;
- Correspondence: (D.S.); (F.O.)
| | | | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Tor Vergata, 00133 Rome, Italy; (M.C.); (G.M.)
| | - Gianluca Manni
- Department of Clinical Sciences and Translational Medicine, University of Tor Vergata, 00133 Rome, Italy; (M.C.); (G.M.)
| | - Francesco Oddone
- IRCCS-Fondazione Bietti, 00198 Rome, Italy;
- Correspondence: (D.S.); (F.O.)
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Zhou Z, Gao Z, Yan W, Zhang Y, Huang J, Xiong K. Adenosine A3 receptor activated in H 2O 2 oxidative stress of primary open-angle glaucoma. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:526. [PMID: 33987224 DOI: 10.21037/atm-20-6154] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Background Primary open-angle glaucoma (POAG), as one of the leading reasons for blindness, is mainly due to trabecular meshwork (TM) dysfunction. Bioinformatics analysis was used to find related genes involved in TM oxidative stress, which is a major cause of TM fibrosis. Methods A total of three datasets from the Gene Expression Omnibus (GEO) database were used to identify differentially expressed genes (DEGs). Gene expression relationships were enriched by the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) pathways. The interaction network was listed by the protein-protein interaction (PPI) network. The expression of adenosine A3 receptor (ADORA3) was validated in POAG tissue and human trabecular meshwork cells (HTMCs) by western blot (WB) and reverse transcription polymerase chain reaction (RT-PCR). Additionally, WB and RT-PCR were used to measure oxidative stress injury relative protein and gene expression, respectively, such as fibronectin (FN), collagen-I (Col-I), and α-smooth muscle actin (α-SMA). Cell migration function and vitality were tested via transwell migration assay and Cell Counting Kit-8 (CCK-8). The cell vitality was measured using CCK-8. Results A total of 61 significant DEGs among the three data sources were analyzed. Among all three different datasets, two significant DEGs [ADORA3 and DNA damage-inducible transcript 4 protein (DDIT4)] were identified. The dataset ADORA3 was selected for further analysis. In the POAG TM tissue, ADORA3 was overexpressed at transcriptional and post-transcriptional levels. Overexpression of ADORA3 reduced TMC viability and migration but upregulated the extracellular matrix (ECM) proteins (FN, Col-I, and α-SMA) expression. It was found that ADORA3 can exacerbate oxidative stress injury in normal TMCs. These results indicated that ADORA3 might play an essential role in the occurrence and progression of POAG. Conclusions A total of 61 novel common DEGs identified are related to the development and prognosis of POAG. In the POAG, ADORA3 was verified as overexpressed; therefore, it may be associated with an oxidative stress injury in TMCs.
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Affiliation(s)
- Ziyu Zhou
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Zhaolin Gao
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Weitao Yan
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Yun Zhang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China
| | - Jufang Huang
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China.,School of Life Sciences, Central South University, Changsha, China
| | - Kun Xiong
- Department of Anatomy and Neurobiology, School of Basic Medical Sciences, Central South University, Changsha, China
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Cathepsin B Localizes in the Caveolae and Participates in the Proteolytic Cascade in Trabecular Meshwork Cells. Potential New Drug Target for the Treatment of Glaucoma. J Clin Med 2020; 10:jcm10010078. [PMID: 33379277 PMCID: PMC7795952 DOI: 10.3390/jcm10010078] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 12/17/2020] [Accepted: 12/24/2020] [Indexed: 12/13/2022] Open
Abstract
Extracellular matrix (ECM) deposition in the trabecular meshwork (TM) is one of the hallmarks of glaucoma, a group of human diseases and leading cause of permanent blindness. The molecular mechanisms underlying ECM deposition in the glaucomatous TM are not known, but it is presumed to be a consequence of excessive synthesis of ECM components, decreased proteolytic degradation, or both. Targeting ECM deposition might represent a therapeutic approach to restore outflow facility in glaucoma. Previous work conducted in our laboratory identified the lysosomal enzyme cathepsin B (CTSB) to be expressed on the cellular surface and to be secreted into the culture media in trabecular meshwork (TM) cells. Here, we further investigated the role of CTSB on ECM remodeling and outflow physiology in vitro and in CSTBko mice. Our results indicate that CTSB localizes in the caveolae and participates in the pericellular degradation of ECM in TM cells. We also report here a novel role of CTSB in regulating the expression of PAI-1 and TGFβ/Smad signaling in TM cells vitro and in vivo in CTSBko mice. We propose enhancing CTSB activity as a novel therapeutic target to attenuate fibrosis and ECM deposition in the glaucomatous outflow pathway.
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18
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Ding F, Shan C, Li H, Zhang Y, Guo C, Zhou Z, Zheng J, Shen W, Dai Q, Ouyang Q, Wu X. Simvastatin alleviated diabetes mellitus-induced erectile dysfunction in rats by enhancing AMPK pathway-induced autophagy. Andrology 2020; 8:780-792. [PMID: 31955524 DOI: 10.1111/andr.12758] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 01/09/2020] [Accepted: 01/14/2020] [Indexed: 12/25/2022]
Abstract
BACKGROUND Diabetes mellitus-induced erectile dysfunction is a common diabetic complication, and new therapeutics and the pathogenesis of diabetes mellitus-induced erectile dysfunction need to be investigated. OBJECTIVES The aim was to investigate the pathogenesis of diabetes mellitus-induced erectile dysfunction and the pharmacological mechanism of simvastatin treatment in diabetes mellitus-induced erectile dysfunction model rats. MATERIALS AND METHODS A total of 86 male Sprague Dawley rats aged 8 weeks old were used in this study. The rats were divided into three groups: control (normal), diabetes mellitus-induced erectile dysfunction (streptozotocin-injected), and diabetes mellitus-induced erectile dysfunction + simvastatin (sim). Each group was subdivided into two subgroups for in vitro and in vivo analyses. A bioinformatics method was used to detect differences in gene expression in the corpus cavernosum between normal and diabetes mellitus-induced erectile dysfunction rats. Erectile function was measured by a cavernous nerve electrostimulation test. Corpus cavernosum fibrosis was assessed by Masson staining and Western blotting. Immunofluorescence and Western blotting were performed to explore the differential expression of autophagy-related genes and the AMPK-SKP2-CARM1 pathway genes in rat cavernous smooth muscle cells and the corpus cavernosum. The autophagosomes of the corpus cavernosum tissue were observed by transmission electron microscopy. RESULTS Autophagy-related genes and pathways (the AMPK and FoxO pathway) were identified by bioinformatics analysis and confirmed at the protein level. Simvastatin, an AMPK agonist, was used to treat diabetes mellitus-induced erectile dysfunction rats for 8 weeks, demonstrating that erectile function was improved for 80.5% (P < .05) of rats. Corpus cavernosum fibrosis was alleviated (P < .05), and autophagy was further enhanced (P < .05); these results might be partially caused by AMPK-SKP2-CARM1 pathway activation (P < .05). DISCUSSION AND CONCLUSION Simvastatin could enhance protective autophagy by activating the AMPK-SKP2-CARM1 pathway to improve erectile function in diabetes mellitus-induced erectile dysfunction rats.
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Affiliation(s)
- Fan Ding
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Changyu Shan
- Department of Pharmaceutical Chemistry, Third Military Medical University, Chongqing, China
| | - Hongwei Li
- Department of Pharmaceutical Chemistry, Third Military Medical University, Chongqing, China
| | - Yuping Zhang
- Department of Pharmaceutical Chemistry, Third Military Medical University, Chongqing, China
| | - Chunling Guo
- Department of Pharmaceutical Chemistry, Third Military Medical University, Chongqing, China
| | - Zhansong Zhou
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Ji Zheng
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Wenhao Shen
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Qiang Dai
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
| | - Qin Ouyang
- Department of Pharmaceutical Chemistry, Third Military Medical University, Chongqing, China
| | - Xiaojun Wu
- Institute of Urinary Surgery, Southwest Hospital, Third Military Medical University, Chongqing, China
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