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Meng K, Lu S, Li Y, Hu L, Zhang J, Cao Y, Wang Y, Zhang CZ, He Q. LINC00493-encoded microprotein SMIM26 exerts anti-metastatic activity in renal cell carcinoma. EMBO Rep 2023; 24:e56282. [PMID: 37009826 PMCID: PMC10240204 DOI: 10.15252/embr.202256282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 03/08/2023] [Accepted: 03/17/2023] [Indexed: 04/04/2023] Open
Abstract
Human microproteins encoded by long non-coding RNAs (lncRNA) have been increasingly discovered, however, complete functional characterization of these emerging proteins is scattered. Here, we show that LINC00493-encoded SMIM26, an understudied microprotein localized in mitochondria, is tendentiously downregulated in clear cell renal cell carcinoma (ccRCC) and correlated with poor overall survival. LINC00493 is recognized by RNA-binding protein PABPC4 and transferred to ribosomes for translation of a 95-amino-acid protein SMIM26. SMIM26, but not LINC00493, suppresses ccRCC growth and metastatic lung colonization by interacting with acylglycerol kinase (AGK) and glutathione transport regulator SLC25A11 via its N-terminus. This interaction increases the mitochondrial localization of AGK and subsequently inhibits AGK-mediated AKT phosphorylation. Moreover, the formation of the SMIM26-AGK-SCL25A11 complex maintains mitochondrial glutathione import and respiratory efficiency, which is abrogated by AGK overexpression or SLC25A11 knockdown. This study functionally characterizes the LINC00493-encoded microprotein SMIM26 and establishes its anti-metastatic role in ccRCC, and therefore illuminates the importance of hidden proteins in human cancers.
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Affiliation(s)
- Kun Meng
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
- The First Affiliated Hospital of Jinan University and MOE Key Laboratory of Tumor Molecular Biology, Jinan UniversityGuangzhouChina
| | - Shaohua Lu
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
- Sino‐French Hoffmann Institute, School of Basic Medical Sciences, State Key Laboratory of Respiratory DiseaseGuangzhou Medical UniversityGuangzhouChina
| | - Yu‐Ying Li
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
| | - Li‐Ling Hu
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
| | - Jing Zhang
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
- The First Affiliated Hospital of Jinan University and MOE Key Laboratory of Tumor Molecular Biology, Jinan UniversityGuangzhouChina
| | - Yun Cao
- Department of Pathology, State Key Laboratory of Oncology in South ChinaSun Yat‐sen University Cancer CenterGuangzhouChina
| | - Yang Wang
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
| | - Chris Zhiyi Zhang
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
| | - Qing‐Yu He
- MOE Key Laboratory of Tumor Molecular Biology and Key Laboratory of Functional Protein Research of Guangdong Higher Education Institutes, Institute of Life and Health Engineering, College of Life Science and Technology, Jinan UniversityGuangzhouChina
- The First Affiliated Hospital of Jinan University and MOE Key Laboratory of Tumor Molecular Biology, Jinan UniversityGuangzhouChina
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Emerging therapeutic roles of small heat shock protein-derived mini-chaperones and their delivery strategies. Biochimie 2022; 208:56-65. [PMID: 36521577 DOI: 10.1016/j.biochi.2022.12.004] [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: 08/26/2022] [Revised: 11/28/2022] [Accepted: 12/08/2022] [Indexed: 12/14/2022]
Abstract
The small heat shock protein (sHsp) family is a group of proteins in which some are induced in response to external stimuli, such as environmental and pathological stresses, while others are constitutively expressed. They show chaperone-like activity, protect cells from apoptosis, and maintain cytoskeletal architecture. Short sequences or fragments ranging from approximately 19-20 residues in sHsps were shown to display chaperone activity in vitro. These sequences are termed sHsp-derived mini-peptides/mini-chaperones. These peptides offer an advantage in providing protective and therapeutic effects over full-length proteins owing to their small molecular weight and easy uptake into the cells. Research on sHsp mini-chaperone therapy has recently received attention and advanced tremendously. sHsp mini-chaperones have shown a wide range of therapeutic effects, such as anti-aggregation of proteins, anti-apoptotic, anti-inflammatory, anti-oxidant, senolytic, and anti-platelet activity. The administration of mini-chaperones into the several disease animal models, including experimental autoimmune encephalomyelitis, cataract, age-related macular degeneration, glaucoma, and thrombosis through various routes reduced symptoms or prevented the progression of the disease. However, it was found that the therapeutic potential of sHsp mini-chaperones is limited by their short turnover and enzymatic degradation in circulation. Nonetheless, carrier molecules approach such as nanoparticles, cell penetration peptides, and extracellular vesicles increased their efficacy by enhancing the uptake, retention time, protection from enzymatic degradation, and site-specific delivery without altering their biological activity. In this context, this review highlights the recent advances in the therapeutic potential of sHsp-derived mini-chaperones, their effect in experimental animal models, and approaches for increasing their efficacy.
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Peptains block retinal ganglion cell death in animal models of ocular hypertension: implications for neuroprotection in glaucoma. Cell Death Dis 2022; 13:958. [PMID: 36379926 PMCID: PMC9666629 DOI: 10.1038/s41419-022-05407-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 11/01/2022] [Accepted: 11/04/2022] [Indexed: 11/16/2022]
Abstract
Ocular hypertension is a significant risk factor for vision loss in glaucoma due to the death of retinal ganglion cells (RGCs). This study investigated the effects of the antiapoptotic peptides peptain-1 and peptain-3a on RGC death in vitro in rat primary RGCs and in mouse models of ocular hypertension. Apoptosis was induced in primary rat RGCs by trophic factor deprivation for 48 h in the presence or absence of peptains. The effects of intravitreally injected peptains on RGC death were investigated in mice subjected to retinal ischemic/reperfusion (I/R) injury and elevated intraocular pressure (IOP). I/R injury was induced in mice by elevating the IOP to 120 mm Hg for 1 h, followed by rapid reperfusion. Ocular hypertension was induced in mice by injecting microbeads (MB) or silicone oil (SO) into the anterior chamber of the eye. Retinal flatmounts were immunostained with RGC and activated glial markers. Effects on anterograde axonal transport were determined by intravitreal injection of cholera toxin-B. Peptain-1 and peptain-3a inhibited neurotrophic factor deprivation-mediated RGC apoptosis by 29% and 35%, respectively. I/R injury caused 52% RGC loss, but peptain-1 and peptain-3a restricted RGC loss to 13% and 16%, respectively. MB and SO injections resulted in 31% and 36% loss in RGCs following 6 weeks and 4 weeks of IOP elevation, respectively. Peptain-1 and peptain-3a inhibited RGC death; the loss was only 4% and 12% in MB-injected eyes and 16% and 15% in SO-injected eyes, respectively. Anterograde transport was defective in eyes with ocular hypertension, but this defect was substantially ameliorated in peptain-injected eyes. Peptains suppressed ocular hypertension-mediated retinal glial activation. In summary, our results showed that peptains block RGC somal and axonal damage and neuroinflammation in animal models of glaucoma. We propose that peptains have the potential to be developed as therapeutics against neurodegeneration in glaucoma.
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Mechanisms of Epithelial-Mesenchymal Transition and Prevention of Dispase-Induced PVR by Delivery of an Antioxidant αB Crystallin Peptide. Antioxidants (Basel) 2022; 11:antiox11102080. [PMID: 36290802 PMCID: PMC9598590 DOI: 10.3390/antiox11102080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Revised: 09/22/2022] [Accepted: 10/19/2022] [Indexed: 11/19/2022] Open
Abstract
Proliferative Vitreoretinopathy (PVR) is a refractory retinal disease whose primary pathogenesis involves the epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells. At present, there is no effective treatment other than surgery for PVR. The purpose of this study was to investigate the effect of αB crystallin peptide (αBC-P) on EMT in PVR. We have previously shown that this peptide is antiapoptotic and regulates RPE redox status. Subconfluent primary human RPE (hRPE) cells were stimulated by TGFβ2 (10 ng/mL) with or without αBC-P (50 or 75 μg/mL) for 48 h and expression of EMT/mesenchymal to epithelial transition (MET) markers was determined. Mitochondrial ROS (mtROS) generation in hRPE cells treated with TGFβ2 was analyzed. The effect of TGFβ2 and αBC-P on oxidative phosphorylation (OXPHOS) and glycolysis in hRPE was studied. RPE cell migration was also assessed. A PVR-like phenotype was induced by intravitreal dispase injection in C57BL/6J mice. PVR progression and potential therapeutic efficiency of αBC-Elastin-like polypeptides (ELP) was studied using fundus photography, OCT imaging, ERG, and histologic analysis of the retina. αSMA, E-cadherin, Vimentin, Fibronectin and, RPE65, and CTGF were analyzed on Day 28. Additionally, the amount of VEGF-A in retinal cell lysates was measured. The EMT-associated αSMA, Vimentin, SNAIL and SLUG showed a significant upregulation with TGFβ2, and their expression was significantly suppressed by cotreatment with αBC-P. The MET-associated markers, E-cadherin and Sirt1, were significantly downregulated by TGFβ2 and were restored by αBC-P. Incubation of hRPE with TGFβ2 for 24 h showed a marked increase in mitochondrial ROS which was noticeably inhibited by αBC-ELP. We also showed that after TGFβ2 treatment, SMAD4 translocated to mitochondria which was blocked by αBC-ELP. Mitochondrial oxygen consumption rate increased with TGFβ2 treatment for 48 h, and αBC-P co-treatment caused a further increase in OCR. Glycolytic functions of RPE were significantly suppressed with αBC-P (75 μg/mL). In addition, αBC-P significantly inhibited the migration from TGFβ2 treatment in hRPE cells. The formation of proliferative membranes was suppressed in the αBC-ELP-treated group, as evidenced by fundus, OCT, and H&E staining in dispase-induced PVR in mice. Furthermore, ERG showed an improvement in c-wave amplitude. In addition, immunostaining showed significant suppression of αSMA and RPE65 expression. It was also observed that αBC-ELP significantly reduced the expression level of vimentin, fibronectin, and CTGF. Our findings suggest that the antioxidant αBC-P may have therapeutic potential in preventing PVR by reversing the phenotype of EMT/MET and improving the mitochondrial function in RPE cells.
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Sreekumar PG, Reddy ST, Hinton DR, Kannan R. Mechanisms of RPE senescence and potential role of αB crystallin peptide as a senolytic agent in experimental AMD. Exp Eye Res 2022; 215:108918. [PMID: 34986369 PMCID: PMC8923947 DOI: 10.1016/j.exer.2021.108918] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2021] [Revised: 12/21/2021] [Accepted: 12/25/2021] [Indexed: 02/03/2023]
Abstract
Oxidative stress in the retinal pigment epithelium (RPE) can cause mitochondrial dysfunction and is likely a causative factor in the pathogenesis of age-related macular degeneration (AMD). Under oxidative stress conditions, some of the RPE cells become senescent and a contributory role for RPE senescence in AMD pathology has been proposed. The purpose of this study is to 1) characterize senescence in human RPE; 2) investigate the effect of an αB Crystallin chaperone peptide (mini Cry) in controlling senescence, in particular by regulating mitochondrial function and senescence-associated secretory phenotype (SASP) production and 3) develop mouse models for studying the role of RPE senescence in dry and nAMD. Senescence was induced in human RPE cells in two ways. First, subconfluent cells were treated with 0.2 μg/ml doxorubicin (DOX); second, subconfluent cells were treated with 500 μM H2O2. Senescence biomarkers (senescence-associated beta-galactosidase (SA-βgal), p21, p16) and mitochondrial proteins (Fis1, DRP1, MFN2, PGC1-α, mtTFA) were analyzed in control and experimental groups. The effect of mini Cry on mitochondrial bioenergetics, glycolysis and SASP was determined. In vivo, retinal degeneration was induced by intravenous injection of NaIO3 (20 mg/kg) and subretinal fibrosis by laser-induced choroidal neovascularization. Increased SA-βgal staining and p16 and p21 expression was observed after DOX- or H2O2-induced senescence and mini Cry significantly decreased senescence-positive cells. The expression of mitochondrial biogenesis proteins PGC-1 and mTFA increased with senescence, and mini Cry reduced expression significantly. Senescent RPE cells were metabolically active, as evidenced by significantly enhanced oxidative phosphorylation and anaerobic glycolysis, mini Cry markedly reduced rates of respiration and glycolysis. Senescent RPE cells maintain a proinflammatory phenotype characterized by significantly increased production of cytokines (IFN-ˠ, TNF-α, IL1-α IL1-β, IL-6, IL-8, IL-10), and VEGF-A; mini Cry significantly inhibited their secretion. We identified and localized senescent RPE cells for the first time in NaIO3-induced retinal degeneration and laser-induced subretinal fibrosis mouse models. We conclude that mini Cry significantly impairs stress-induced senescence by modulating mitochondrial biogenesis and fission proteins in RPE cells. Characterization of senescence could provide further understanding of the metabolic changes that accompany the senescent phenotype in ocular disease. Future studies in vivo may better define the role of senescence in AMD and the therapeutic potential of mini Cry as a senotherapeutic.
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Affiliation(s)
- Parameswaran G Sreekumar
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA, 90033, USA.
| | - Srinivasa T Reddy
- Department of Molecular and Medical Pharmacology, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, CA, 90095, USA.
| | - David R Hinton
- Department of Pathology and Ophthalmology, USC Roski Eye Institute, Keck School of Medicine of the University of Southern California, Los Angeles, CA, USA.
| | - Ram Kannan
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA, 90033, USA; Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
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Wu DI, Kase S, Liu YE, Kanda A, Murata M, Ishida S. Downregulation of AlphaB-crystallin in Retinal Pigment Epithelial Cells Exposed to Diabetes-related Stimuli In Vivo and In Vitro. In Vivo 2022; 36:132-139. [PMID: 34972708 DOI: 10.21873/invivo.12684] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2021] [Revised: 10/17/2021] [Accepted: 10/19/2021] [Indexed: 12/25/2022]
Abstract
BACKGROUND/AIM AlphaB-crystallin plays a pivotal role in many diseases. However, the involvement of alphaB-crystallin in retinal pigment epithelial (RPE) cells with diabetes stimuli remains unknown. The aim of this study is to examine the alterations of RPE cells and alphaB-crystallin expression in diabetic models in vivo and in vitro. MATERIALS AND METHODS Diabetic conditions in mice were induced by streptozotocin (STZ). The thickness of the RPE/choroid complex was measured by optical coherence tomography (OCT). Periodic acid-Schiff (PAS) staining was used to investigate the choriocapillaris in histological sections of murine eyeballs and oxidative stress was evaluated using immunofluorescence with anti-4-hydroxynonenal (HNE) antibody. AlphaB-crystallin expression was examined in the RPE/choroid complex using ELISA. Real-Time PCR was performed to evaluate the alphaB-crystallin expression in cultured human RPE cells with high glucose or following advanced glycation end-products (AGE) stimulation. RESULTS In diabetic mice, OCT-based RPE/choroidal layers were thickened 2 months after STZ stimulation, where PAS-positive dilated choriocapillaris was noted. Immunoreactivity of 4-HNE was strongly observed in the RPE layer, from which a significant number of RPE cells was lost. Meanwhile, alphaB-crystallin expression in 2-month STZ mice was significantly lower compared to controls. In accordance with these results, in vitro data showed that the alphaB-crystallin expression was also significantly lower in RPE cells with high glucose or following AGE stimulation compared to untreated cells. CONCLUSION In both types of diabetic models the expression of alphaB-crystallin was found to be downregulated in RPE cells and was associated with increased levels of oxidative stress.
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Affiliation(s)
- D I Wu
- Eye Center of the Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, P.R. China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, P.R. China.,Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Satoru Kase
- Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Y E Liu
- Eye Center of the Second Affiliated Hospital of Zhejiang University, School of Medicine, Hangzhou, P.R. China.,Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, P.R. China.,Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Atsuhiro Kanda
- Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Miyuki Murata
- Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
| | - Susumu Ishida
- Laboratory of Ocular Cell Biology and Visual Science, Department of Ophthalmology, Faculty of Medicine and Graduate School of Medicine, Hokkaido University, Sapporo, Japan
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Sreekumar PG, Ferrington DA, Kannan R. Glutathione Metabolism and the Novel Role of Mitochondrial GSH in Retinal Degeneration. Antioxidants (Basel) 2021; 10:661. [PMID: 33923192 PMCID: PMC8146950 DOI: 10.3390/antiox10050661] [Citation(s) in RCA: 40] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2021] [Revised: 04/18/2021] [Accepted: 04/21/2021] [Indexed: 02/06/2023] Open
Abstract
Glutathione (GSH) is present ubiquitously, and its role as a crucial cellular antioxidant in tissues, including the retina, is well established. GSH's antioxidant function arises from its ability to scavenge reactive oxygen species or to serve as an essential cofactor for GSH S-transferases and peroxidases. This review summarizes the general functions, retinal distribution, disorders linked to GSH deficiency, and the emerging role for mitochondrial GSH (mGSH) in retinal function. Though synthesized only in the cytosol, the presence of GSH in multiple cell organelles suggests the requirement for its active transport across organellar membranes. The localization and distribution of 2-oxoglutarate carrier (OGC) and dicarboxylate carrier (DIC), two recently characterized mitochondrial carrier proteins in RPE and retina, show that these transporters are highly expressed in human retinal pigment epithelium (RPE) cells and retinal layers, and their expression increases with RPE polarity in cultured cells. Depletion of mGSH levels via inhibition of the two transporters resulted in reduced mitochondrial bioenergetic parameters (basal respiration, ATP production, maximal respiration, and spare respiratory capacity) and increased RPE cell death. These results begin to reveal a critical role for mGSH in maintaining RPE bioenergetics and cell health. Thus, augmentation of mGSH pool under GSH-deficient conditions may be a valuable tool in treating retinal disorders, such as age-related macular degeneration and optic neuropathies, whose pathologies have been associated with mitochondrial dysfunction.
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Affiliation(s)
- Parameswaran G. Sreekumar
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA 90033, USA;
| | - Deborah A. Ferrington
- Department of Ophthalmology and Visual Neurosciences and Stem Cell Institute, University of Minnesota, Minneapolis, MN 55455, USA;
| | - Ram Kannan
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA 90033, USA;
- Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA 90095, USA
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Sreekumar PG, Kannan R. Mechanisms of protection of retinal pigment epithelial cells from oxidant injury by humanin and other mitochondrial-derived peptides: Implications for age-related macular degeneration. Redox Biol 2020; 37:101663. [PMID: 32768357 PMCID: PMC7767738 DOI: 10.1016/j.redox.2020.101663] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2020] [Revised: 07/18/2020] [Accepted: 07/26/2020] [Indexed: 02/06/2023] Open
Abstract
The mitochondrial-derived peptides (MDPs) are a new class of small open reading frame encoded polypeptides with pleiotropic properties. The prominent members are Humanin (HN) and small HN-like peptide (SHLP) 2, which encode 16S rRNA, while mitochondrial open reading frame of the twelve S c (MOTS-c) encodes 12S rRNA of the mitochondrial genome. While the multifunctional properties of HN and its analog 14-HNG have been well documented, their protective role in the retinal pigment epithelium (RPE)/retina has been investigated only recently. In this review, we have summarized the multiple effects of HN and its analogs, SHLP2 and MOTS-c in oxidatively stressed human RPE and the regulatory pathways of signaling, mitochondrial function, senescence, and inter-organelle crosstalk. Emphasis is given to the mitochondrial functions such as biogenesis, bioenergetics, and autophagy in RPE undergoing oxidative stress. Further, the potential use of HN and its analogs in the prevention of age-related macular degeneration (AMD) are also presented. In addition, the role of novel, long-acting HN elastin-like polypeptides in nanotherapy of AMD and other ocular diseases stemming from oxidative damage is discussed. It is expected MDPs will become a promising group of mitochondrial peptides with valuable therapeutic applications in the treatment of retinal diseases.
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Affiliation(s)
- Parameswaran G Sreekumar
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA, 90033, USA
| | - Ram Kannan
- The Stephen J. Ryan Initiative for Macular Research (RIMR), Doheny Eye Institute, Los Angeles, CA, 90033, USA; Stein Eye Institute, Geffen School of Medicine, University of California, Los Angeles, CA, 90095, USA.
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