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Wang Y, Zhang YR, Ding ZQ, Zhang YC, Sun RX, Zhu HJ, Wang JN, Xu B, Zhang P, Ji JD, Liu QH, Chen X. m6A-Mediated Upregulation of Imprinted in Prader-Willi Syndrome Induces Aberrant Apical-Basal Polarization and Oxidative Damage in RPE Cells. Invest Ophthalmol Vis Sci 2024; 65:10. [PMID: 38315495 PMCID: PMC10851782 DOI: 10.1167/iovs.65.2.10] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 01/09/2024] [Indexed: 02/07/2024] Open
Abstract
Purpose To reveal the clinical significance, pathological involvement and molecular mechanism of imprinted in Prader-Willi syndrome (IPW) in RPE anomalies that contribute to AMD. Methods IPW expression under pathological conditions were detected by microarrays and qPCR assays. In vitro cultured fetal RPE cells were used to study the pathogenicity induced by IPW overexpression and to analyze its upstream and downstream regulatory networks. Results We showed that IPW is upregulated in the macular RPE-choroid tissue of dry AMD patients and in fetal RPE cells under oxidative stress, inflammation and dedifferentiation. IPW overexpression in fetal RPE cells induced aberrant apical-basal polarization as shown by dysregulated polarized markers, disrupted tight and adherens junctions, and inhibited phagocytosis. IPW upregulation was also associated with RPE oxidative damages, as demonstrated by intracellular accumulation of reactive oxygen species, reduced cell proliferation, and accelerated cell apoptosis. Mechanically, N6-methyladenosine level of the IPW transcript regulated its stability with YTHDC1 as the reader. IPW mediated RPE features by suppressing MEG3 expression to sequester its inhibition on the AKT serine-threonine kinase (AKT)/mammalian target of rapamycin (mTOR) pathway. We also noticed that the mTOR inhibitor rapamycin suppresses the AKT/mTOR pathway to alleviate the IPW-induced RPE anomalies. Conclusions We revealed that IPW overexpression in RPE induces aberrant apical-basal polarization and oxidative damages, thus contributing to AMD progression. We also annotated the upstream and downstream regulatory networks of IPW in RPE. Our findings shed new light on the molecular mechanisms of RPE dysfunctions, and indicate that IPW blockers may be a promising option to treat RPE abnormalities in AMD.
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Affiliation(s)
- Ying Wang
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Ye-Ran Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Zi-Qin Ding
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Yi-Chen Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Ru-Xu Sun
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Hong-Jing Zhu
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Jia-Nan Wang
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Bei Xu
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Ping Zhang
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Jiang-Dong Ji
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Qing-Huai Liu
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
| | - Xue Chen
- Department of Ophthalmology, The First Affiliated Hospital of Nanjing Medical University, Nanjing Medical University, Nanjing, China
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Wu AYT, Sekar P, Huang DY, Hsu SH, Chan CM, Lin WW. Spatiotemporal roles of AMPK in PARP-1- and autophagy-dependent retinal pigment epithelial cell death caused by UVA. J Biomed Sci 2023; 30:91. [PMID: 37936170 PMCID: PMC10629085 DOI: 10.1186/s12929-023-00978-4] [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: 05/15/2023] [Accepted: 09/29/2023] [Indexed: 11/10/2023] Open
Abstract
BACKGROUND Although stimulating autophagy caused by UV has been widely demonstrated in skin cells to exert cell protection, it remains unknown the cellular events in UVA-treated retinal pigment epithelial (RPE) cells. METHODS Human ARPE-19 cells were used to measure cell viability, mitochondrial reactive oxygen species (ROS), mitochondrial membrane potential (MMP), mitochondrial mass and lysosomal mass by flow cytometry. Mitochondrial oxygen consumption rate (OCR) was recorded using Seahorse XF flux analyzer. Confocal microscopic images were performed to indicate the mitochondrial dynamics, LC3 level, and AMPK translocation after UVA irradiation. RESULTS We confirmed mitochondrial ROS production and DNA damage are two major features caused by UVA. We found the cell death is prevented by autophagy inhibitor 3-methyladenine and gene silencing of ATG5, and UVA induces ROS-dependent LC3II expression, LC3 punctate and TFEB expression, suggesting the autophagic death in the UVA-stressed RPE cells. Although PARP-1 inhibitor olaparib increases DNA damage, ROS production, and cell death, it also blocks AMPK activation caused by UVA. Interestingly we found a dramatic nuclear export of AMPK upon UVA irradiation which is blocked by N-acetylcysteine and olaparib. In addition, UVA exposure gradually decreases lysosomal mass and inhibits cathepsin B activity at late phase due to lysosomal dysfunction. Nevertheless, cathepsin B inhibitor, CA-074Me, reverses the death extent, suggesting the contribution of cathepsin B in the death pathway. When examining the role of EGFR in cellular events caused by UVA, we found that UVA can rapidly transactivate EGFR, and treatment with EGFR TKIs (gefitinib and afatinib) enhances the cell death accompanied by the increased LC3II formation, ROS production, loss of MMP and mass of mitochondria and lysosomes. Although AMPK activation by ROS-PARP-1 mediates autophagic cell death, we surprisingly found that pretreatment of cells with AMPK activators (A769662 and metformin) reverses cell death. Concomitantly, both agents block UVA-induced mitochondrial ROS production, autophagic flux, and mitochondrial fission without changing the inhibition of cathepsin B. CONCLUSION UVA exposure rapidly induces ROS-PARP-1-AMPK-autophagic flux and late lysosomal dysfunction. Pre-inducing AMPK activation can prevent cellular events caused by UVA and provide a new protective strategy in photo-oxidative stress and photo-retinopathy.
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Affiliation(s)
- Anthony Yan-Tang Wu
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Chemical Biology and Molecular Biophysics Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan
| | - Ponarulselvam Sekar
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan
| | - Duen-Yi Huang
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan
| | - Shu-Hao Hsu
- Department of Ophthalmology, Cardinal Tien Hospital, New Taipei City, Taiwan
| | - Chi-Ming Chan
- Department of Ophthalmology, Cardinal Tien Hospital, New Taipei City, Taiwan.
- School of Medicine, Fu Jen Catholic University, New Taipei City, Taiwan.
| | - Wan-Wan Lin
- Department of Pharmacology, College of Medicine, National Taiwan University, Taipei, Taiwan.
- Chemical Biology and Molecular Biophysics Program, Taiwan International Graduate Program, Academia Sinica, Taipei, Taiwan.
- Graduate Institute of Medical Sciences, Taipei Medical University, Taipei, Taiwan.
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Yang C, Yang R, Gu M, Hao J, Wang S, Li C. Chitooligosaccharides Derivatives Protect ARPE-19 Cells against Acrolein-Induced Oxidative Injury. Mar Drugs 2023; 21:md21030137. [PMID: 36976187 PMCID: PMC10058944 DOI: 10.3390/md21030137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 02/13/2023] [Accepted: 02/20/2023] [Indexed: 02/24/2023] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of vision loss among the elderly. The progression of AMD is closely related to oxidative stress in the retinal pigment epithelium (RPE). Here, a series of chitosan oligosaccharides (COSs) and N-acetylated derivatives (NACOSs) were prepared, and their protective effects on an acrolein-induced oxidative stress model of ARPE-19 were explored using the MTT assay. The results showed that COSs and NACOs alleviated APRE-19 cell damage induced by acrolein in a concentration-dependent manner. Among these, chitopentaose (COS–5) and its N-acetylated derivative (N–5) showed the best protective activity. Pretreatment with COS–5 or N–5 could reduce intracellular and mitochondrial reactive oxygen species (ROS) production induced by acrolein, increase mitochondrial membrane potential, GSH level, and the enzymatic activity of SOD and GSH-Px. Further study indicated that N–5 increased the level of nuclear Nrf2 and the expression of downstream antioxidant enzymes. This study revealed that COSs and NACOSs reduced the degeneration and apoptosis of retinal pigment epithelial cells by enhancing antioxidant capacity, suggesting that they have the potential to be developed into novel protective agents for AMD treatment and prevention.
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Affiliation(s)
- Cheng Yang
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Rongrong Yang
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Ming Gu
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
| | - Jiejie Hao
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China
| | - Shixin Wang
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory of Marine Glycodrug Research and Development, Marine Biomedical Research Institute of Qingdao, Qingdao 266071, China
- Correspondence: (S.W.); (C.L.); Tel.: +86-532-8203-1631 (C.L.); Fax: +86-532-8203-3054 (C.L.)
| | - Chunxia Li
- Shandong Key Laboratory of Glycoscience and Glycotechnology, Key Laboratory of Marine Drugs of Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, China
- Laboratory for Marine Drugs and Bioproducts, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao 266237, China
- Laboratory of Marine Glycodrug Research and Development, Marine Biomedical Research Institute of Qingdao, Qingdao 266071, China
- Correspondence: (S.W.); (C.L.); Tel.: +86-532-8203-1631 (C.L.); Fax: +86-532-8203-3054 (C.L.)
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Tong Y, Zhang Z, Wang S. Role of Mitochondria in Retinal Pigment Epithelial Aging and Degeneration. FRONTIERS IN AGING 2022; 3:926627. [PMID: 35912040 PMCID: PMC9337215 DOI: 10.3389/fragi.2022.926627] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/22/2022] [Accepted: 06/21/2022] [Indexed: 12/17/2022]
Abstract
Retinal pigment epithelial (RPE) cells form a monolayer between the neuroretina and choroid. It has multiple important functions, including acting as outer blood-retina barrier, maintaining the function of neuroretina and photoreceptors, participating in the visual cycle and regulating retinal immune response. Due to high oxidative stress environment, RPE cells are vulnerable to dysfunction, cellular senescence, and cell death, which underlies RPE aging and age-related diseases, including age-related macular degeneration (AMD). Mitochondria are the powerhouse of cells and a major source of cellular reactive oxygen species (ROS) that contribute to mitochondrial DNA damage, cell death, senescence, and age-related diseases. Mitochondria also undergo dynamic changes including fission/fusion, biogenesis and mitophagy for quality control in response to stresses. The role of mitochondria, especially mitochondrial dynamics, in RPE aging and age-related diseases, is still unclear. In this review, we summarize the current understanding of mitochondrial function, biogenesis and especially dynamics such as morphological changes and mitophagy in RPE aging and age-related RPE diseases, as well as in the biological processes of RPE cellular senescence and cell death. We also discuss the current preclinical and clinical research efforts to prevent or treat RPE degeneration by restoring mitochondrial function and dynamics.
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Affiliation(s)
- Yao Tong
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| | - Zunyi Zhang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
| | - Shusheng Wang
- Department of Cell and Molecular Biology, Tulane University, New Orleans, LA, United States
- Department of Ophthalmology, Tulane University, New Orleans, LA, United States
- Tulane Personalized Health Institute, Tulane University, New Orleans, LA, United States
- *Correspondence: Shusheng Wang,
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Xie R, Wang B, Zuo S, Du M, Wang X, Yu Y, Yan H. Protective effects of CRTH2 suppression in dry age-related macular degeneration. Biochem Biophys Res Commun 2022; 624:8-15. [DOI: 10.1016/j.bbrc.2022.07.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 06/30/2022] [Accepted: 07/02/2022] [Indexed: 11/27/2022]
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Shukal DK, Malaviya PB, Sharma T. Role of the AMPK signalling pathway in the aetiopathogenesis of ocular diseases. Hum Exp Toxicol 2022; 41:9603271211063165. [PMID: 35196887 DOI: 10.1177/09603271211063165] [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] [Indexed: 12/13/2022]
Abstract
BACKGROUND AMP-activated protein kinase (AMPK) plays a precise role as a master regulator of cellular energy homeostasis. AMPK is activated in response to the signalling cues that exhaust cellular ATP levels such as hypoxia, ischaemia, glucose depletion and heat shock. As a central regulator of both lipid and glucose metabolism, AMPK is considered to be a potential therapeutic target for the treatment of various diseases, including eye disorders. OBJECTIVE To review all the shreds of evidence concerning the role of the AMPK signalling pathway in the pathogenesis of ocular diseases. METHOD Scientific data search and review of available information evaluating the influence of AMPK signalling on ocular diseases. RESULTS Review highlights the significance of AMPK signalling in the aetiopathogenesis of ocular diseases, including cataract, glaucoma, diabetic retinopathy, retinoblastoma, age-related macular degeneration, corneal diseases, etc. The review also provides the information on the AMPK-associated pathways with reference to ocular disease, which includes mitochondrial biogenesis, autophagy and regulation of inflammatory response. CONCLUSION The study concludes the role of AMPK in ocular diseases. There is growing interest in the therapeutic utilization of the AMPK pathway for ocular disease treatment. Furthermore, inhibition of AMPK signalling might represent more pertinent strategy than AMPK activation for ocular disease treatment. Such information will guide the development of more effective AMPK modulators for ocular diseases.[Formula: see text].
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Affiliation(s)
- Dhaval K Shukal
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India.,76793Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Pooja B Malaviya
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India.,76793Manipal Academy of Higher Education, Mangalore, Karnataka, India
| | - Tusha Sharma
- 534329Iladevi Cataract and IOL Research Centre, Memnagar, Ahmedabad, Gujarat, India
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Chuang CJ, Wang M, Yeh JH, Chen TC, Tsou SC, Lee YJ, Chang YY, Lin HW. The Protective Effects of α-Mangostin Attenuate Sodium Iodate-Induced Cytotoxicity and Oxidative Injury via Mediating SIRT-3 Inactivation via the PI3K/AKT/PGC-1 α Pathway. Antioxidants (Basel) 2021; 10:antiox10121870. [PMID: 34942973 PMCID: PMC8698330 DOI: 10.3390/antiox10121870] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/16/2021] [Accepted: 11/19/2021] [Indexed: 11/16/2022] Open
Abstract
It is well known that age-related macular degeneration (AMD) is an irreversible neurodegenerative disease that can cause blindness in the elderly. Oxidative stress-induced retinal pigment epithelial (RPE) cell damage is a part of the pathogenesis of AMD. In this study, we evaluated the protective effect and mechanisms of alpha-mangostin (α-mangostin, α-MG) against NaIO3-induced reactive oxygen species (ROS)-dependent toxicity, which activates apoptosis in vivo and in vitro. MTT assay and flow cytometry demonstrated that the pretreatment of ARPE-19 cells with α-MG (0, 3.75, 7.5, and 15 μM) significantly increased cell viability and reduced apoptosis from NaIO3-induced oxidative stress in a concentration-dependent manner, which was achieved by the inhibition of Bax, cleaved PARP-1, cleaved caspase-3 protein expression, and enhancement of Bcl-2 protein. Furthermore, pre-incubation of ARPE-19 cells with α-MG markedly inhibited the intracellular ROS and extracellular H2O2 generation via blocking of the abnormal enzyme activities of superoxide dismutase (SOD), the downregulated levels of catalase (CAT), and the endogenous antioxidant, glutathione (GSH), which were regulated by decreasing PI3K-AKT-PGC-1α-STRT-3 signaling in ARPE-19 cells. In addition, our in vivo results indicated that α-MG improved retinal deformation and increased the thickness of both the outer nuclear layer and inner nuclear layer by inhibiting the expression of cleaved caspase-3 protein. Taken together, our results suggest that α-MG effectively protects human ARPE-19 cells from NaIO3-induced oxidative damage via antiapoptotic and antioxidant effects.
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Affiliation(s)
- Chen-Ju Chuang
- Emergency Department, Kaohsiung Municipal United Hospital, Kaohsiung 80457, Taiwan;
| | - Meilin Wang
- Department of Microbiology and Immunology, School of Medicine, Chung Shan Medical University and Clinical Laboratory, Chung Shan Medical University Hospital, Taichung 40201, Taiwan;
| | - Jui-Hsuan Yeh
- Institute of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (J.-H.Y.); (T.-C.C.)
| | - Tzu-Chun Chen
- Institute of Medicine, Chung Shan Medical University, Taichung 40201, Taiwan; (J.-H.Y.); (T.-C.C.)
| | - Shang-Chun Tsou
- Department of Nutrition, Chung Shan Medical University, Taichung 40201, Taiwan;
| | - Yi-Ju Lee
- Department of Pathology, Chung-Shan Medical University, Chung-Shan Medical University Hospital, Taichung 40201, Taiwan;
| | - Yuan-Yen Chang
- Department of Microbiology and Immunology, School of Medicine, Chung Shan Medical University and Clinical Laboratory, Chung Shan Medical University Hospital, Taichung 40201, Taiwan;
- Correspondence: (Y.-Y.C.); (H.-W.L.); Tel.: +886-4-24730022 (ext. 12028)
| | - Hui-Wen Lin
- Department of Optometry, Asia University, Taichung 41354, Taiwan
- Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
- Correspondence: (Y.-Y.C.); (H.-W.L.); Tel.: +886-4-24730022 (ext. 12028)
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Shiwani HA, Elfaki MY, Memon D, Ali S, Aziz A, Egom EE. Updates on sphingolipids: Spotlight on retinopathy. Biomed Pharmacother 2021; 143:112197. [PMID: 34560541 DOI: 10.1016/j.biopha.2021.112197] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Revised: 09/08/2021] [Accepted: 09/13/2021] [Indexed: 02/05/2023] Open
Abstract
The sphingolipids ceramide (Cer), ceramide-1-phosphate (C1P), sphingosine (Sph), and sphingosine-1-phosphate (S1P)) are key signaling molecules that regulate many patho-biological processes. During the last decade, they have gained increasing attention since they may participate in important and numerous retinal processes, such as neuronal survival and death, proliferation and migration of neuronal and vascular cells, inflammation, and neovascularization. Cer for instance has emerged as a key mediator of inflammation and death of neuronal and retinal pigment epithelium cells in experimental models of retinopathies such as glaucoma, age-related macular degeneration (AMD), and retinitis pigmentosa. S1P may have opposite biological actions, preventing photoreceptor and ganglion cell degeneration but also promoting inflammation, fibrosis, and neovascularization in AMD, glaucoma, and pro-fibrotic disorders. Alterations in Cer, S1P, and ceramide 1- phosphate may also contribute to uveitis. Furthermore, use of inhibitors that either prevent Cer increase or modulate S1P signaling, such as Myriocin, desipramine, and Fingolimod (FTY720), have been shown to preserve neuronal viability and retinal function. Collectively, the expanding role for these sphingolipids in the modulation of vital processes in retina cell types and in their dysregulation in retinal degenerations makes them attractive therapeutic targets.
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Affiliation(s)
- Haaris A Shiwani
- Department of Ophthalmology, Royal Preston Hospital, United Kingdom.
| | | | - Danyal Memon
- Department of Cardiology, Children's Health Ireland at Crumlin, Dublin, Ireland
| | - Suhayb Ali
- Department of Acute Medicine, Ulster Hospital, Belfast, United Kingdom
| | - Abdul Aziz
- Department of Respiratory Medicine, Royal Liverpool University Hospital, Liverpool, United Kingdom
| | - Emmanuel E Egom
- Institut du Savoir Montfort (ISM), Hôpital Montfort, University of Ottawa, Ottawa, ON, Canada; Laboratory of Endocrinology and Radioisotopes, Institute of Medical Research and Medicinal Plants Studies (IMPM), Yaoundé, Cameroon.
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MicroRNA-100 Mediates Hydrogen Peroxide-Induced Apoptosis of Human Retinal Pigment Epithelium ARPE-19 Cells. Pharmaceuticals (Basel) 2021; 14:ph14040314. [PMID: 33915898 PMCID: PMC8067261 DOI: 10.3390/ph14040314] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Revised: 03/19/2021] [Accepted: 03/25/2021] [Indexed: 11/20/2022] Open
Abstract
This study investigated the regulatory role of microRNA 100 (miR-100) in hydrogen peroxide (H2O2)-induced apoptosis of human retinal pigment epithelial ARPE-19 cells. H2O2 induced oxidative cell death of cultured ARPE-19 cells was measured by cytotoxicity assay. qRT-PCR was used to quantify cytosolic and extracellular contents of miR-100. Kinase and miR-100 inhibition treatments were applied to determine the regulatory signaling pathways involved in cell death regulation. H2O2 dose-dependently reduced viability of ARPE-19 cells and simultaneously upregulated miR-100 levels in both cytosolic and extracellular compartments. Western blotting detection indicated that H2O2 elicited hyperphosphorylation of PI3K/Akt, ERK1/2, JNK, p38 MAPK, and p65 NF-κB. Further kinase inhibition experiments demonstrated that PI3K, p38 MAPK, and NF-κB activities were involved in oxidative-stress-induced miR-100 upregulation in ARPE-19 cells, while blockade of PI3K, JNK, and NF-κB signaling significantly attenuated the oxidative cell death. Intriguingly, MiR-100 antagomir treatment exerted a cytoprotective effect against the H2O2-induced oxidative cell death through attenuating the oxidation-induced AMPK hyperphosphorylation, restoring cellular mTOR and p62/SQSTM1 levels and upregulating heme oxygenase-1 expression. These findings support that miR-100 at least in part mediates H2O2-induced cell death of ARPE-19 cells and can be regarded as a preventive and therapeutic target for retinal degenerative disease.
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Huang DR, Dai CM, Li SY, Li XF. Obacunone protects retinal pigment epithelium cells from ultra-violet radiation-induced oxidative injury. Aging (Albany NY) 2021; 13:11010-11025. [PMID: 33535179 PMCID: PMC8109142 DOI: 10.18632/aging.202437] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2020] [Accepted: 08/08/2020] [Indexed: 12/22/2022]
Abstract
Ultra-violet (UV) radiation (UVR) causes significant oxidative injury to retinal pigment epithelium (RPE) cells. Obacunone is a highly oxygenated triterpenoid limonoid compound with various pharmacological properties. Its potential effect in RPE cells has not been studied thus far. Here in ARPE-19 cells and primary murine RPE cells, obacunone potently inhibited UVR-induced reactive oxygen species accumulation, mitochondrial depolarization, lipid peroxidation and single strand DNA accumulation. UVR-induced RPE cell death and apoptosis were largely alleviated by obacunone. Obacunone activated Nrf2 signaling cascade in RPE cells, causing Keap1-Nrf2 disassociation, Nrf2 protein stabilization and nuclear translocation. It promoted transcription and expression of antioxidant responsive element-dependent genes. Nrf2 silencing or CRISPR/Cas9-induced Nrf2 knockout almost reversed obacunone-induced RPE cytoprotection against UVR. Forced activation of Nrf2 cascade, by Keap1 knockout, similarly protected RPE cells from UVR. Importantly, obacunone failed to offer further RPE cytoprotection against UVR in Keap1-knockout cells. In vivo, intravitreal injection of obacunone largely inhibited light-induced retinal damage. Collectively, obacunone protects RPE cells from UVR-induced oxidative injury through activation of Nrf2 signaling cascade.
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Affiliation(s)
- Da-Rui Huang
- Department of Ophthalmology, The Affiliated Huaian NO.1 People's Hospital of Nanjing Medical University, Huaian, China
| | - Chang-Ming Dai
- Department of Ophthalmology, The Affiliated Huaian NO.1 People's Hospital of Nanjing Medical University, Huaian, China
| | - Shu-Yan Li
- Department of Ophthalmology, The Affiliated Huaian NO.1 People's Hospital of Nanjing Medical University, Huaian, China
| | - Xiao-Feng Li
- Department of Ophthalmology, The Affiliated Huaian NO.1 People's Hospital of Nanjing Medical University, Huaian, China
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Kim DH, Kim JH, Hwangbo H, Kim SY, Ji SY, Kim MY, Cha HJ, Park C, Hong SH, Kim GY, Park SK, Jeong JW, Kim MY, Choi YH, Lee H. Spermidine Attenuates Oxidative Stress-Induced Apoptosis via Blocking Ca 2+ Overload in Retinal Pigment Epithelial Cells Independently of ROS. Int J Mol Sci 2021; 22:ijms22031361. [PMID: 33572992 PMCID: PMC7866386 DOI: 10.3390/ijms22031361] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 01/26/2021] [Accepted: 01/26/2021] [Indexed: 02/06/2023] Open
Abstract
Retinal pigment epithelial (RPE) cells occupy the outer layer of the retina and perform various biological functions. Oxidative damage to RPE cells is a major risk factor for retinal degeneration that ultimately leads to vision loss. In this study, we investigated the role of spermidine in a hydrogen peroxide (H2O2)-induced oxidative stress model using human RPE cells. Our findings showed that 300 μM H2O2 increased cytotoxicity, apoptosis, and cell cycle arrest in the G2/M phase, whereas these effects were markedly suppressed by 10 μM spermidine. Furthermore, spermidine significantly reduced H2O2-induced mitochondrial dysfunction including mitochondrial membrane potential and mitochondrial activity. Although spermidine displays antioxidant properties, the generation of intracellular reactive oxygen species (ROS) upon H2O2 insult was not regulated by spermidine. Spermidine did suppress the increase in cytosolic Ca2+ levels resulting from endoplasmic reticulum stress in H2O2-stimulated human RPE cells. Treatment with a cytosolic Ca2+ chelator markedly reversed H2O2-induced cellular dysfunction. Overall, spermidine protected against H2O2-induced cellular damage by blocking the increase of intracellular Ca2+ independently of ROS. These results suggest that spermidine protects RPE cells from oxidative stress, which could be a useful treatment for retinal diseases.
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Affiliation(s)
- Da Hye Kim
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - Jeong-Hwan Kim
- Research and Development Department, BGN CARE Co., Ltd., Busan 47195, Korea; (J.-H.K.); (S.-K.P.); (M.-Y.K.)
| | - Hyun Hwangbo
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - So Young Kim
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - Seon Yeong Ji
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - Min Yeong Kim
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - Hee-Jae Cha
- Department of Parasitology and Genetics, Kosin University College of Medicine, Busan 49267, Korea;
| | - Cheol Park
- Department of Molecular Biology, College of Natural Sciences, Dong-eui University, Busan 47340, Korea;
| | - Su Hyun Hong
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
| | - Gi-Young Kim
- Department of Marine Life Science, Jeju National University, Jeju 63243, Korea;
| | - Seh-Kwang Park
- Research and Development Department, BGN CARE Co., Ltd., Busan 47195, Korea; (J.-H.K.); (S.-K.P.); (M.-Y.K.)
- BGN Eye Clinic, Seoul 05551, Korea
| | | | - Mi-Young Kim
- Research and Development Department, BGN CARE Co., Ltd., Busan 47195, Korea; (J.-H.K.); (S.-K.P.); (M.-Y.K.)
| | - Yung Hyun Choi
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
- Correspondence: (Y.H.C.); (H.L.); Tel.: +82-51-890-3319 (Y.H.C.); +82-51-890-3315 (H.L.)
| | - Hyesook Lee
- Anti-Aging Research Center, Dong-eui University, Busan 47340, Korea; (D.H.K.); (H.H.); (S.Y.K.); (S.Y.J.); (M.Y.K.); (S.H.H.)
- Department of Biochemistry, Dong-eui University College of Korean Medicine, Busan 47227, Korea
- Correspondence: (Y.H.C.); (H.L.); Tel.: +82-51-890-3319 (Y.H.C.); +82-51-890-3315 (H.L.)
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Yang Y, Xu G, Xu Y, Cheng X, Xu S, Chen S, Wu L. Ceramide mediates radiation-induced germ cell apoptosis via regulating mitochondria function and MAPK factors in Caenorhabditis elegans. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 208:111579. [PMID: 33396102 DOI: 10.1016/j.ecoenv.2020.111579] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 10/26/2020] [Accepted: 10/27/2020] [Indexed: 06/12/2023]
Abstract
Studies about radiation damage in vivo are very significant for healthy risk assessment as well as cancer radiotherapy. Ceramide as a second messenger has been found to be related to radiation-induced apoptosis. However, the detailed mechanisms in living systems are still not fully understood. In the present study, the effects of ceramide in gamma radiation-induced response were investigated using Caenorhabditis elegans. Our results indicated that ceramide was required for gamma radiation-induced whole-body germ cell apoptosis by the production of radical oxygen species and decrease of mitochondrial transmembrane potential. Using genetic ceramide synthase-related mutated strains and exogenous C16-ceramide, we illustrated that ceramide could regulate DNA damage response (DDR) pathway to mediate radiation-induced germ cell apoptosis. Moreover, ceramide was found to function epistatic to pmk-1 and mpk-1 in MAPK pathway to promote radiation-induced apoptosis in Caenorhabditis elegans. These results demonstrated ceramide could potentially mediated gamma radiation-induced apoptosis through regulating mitochondrial function, DDR pathway and MAPK pathway.
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Affiliation(s)
- Yaning Yang
- Anhui Provincial Engineering Laboratory of Water and Soil Pollution Control and Remediation, School of Ecology and Environment, Anhui Normal University, Wuhu, Anhui 241002, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Guangmin Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Yun Xu
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Xiaowen Cheng
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China
| | - Shengmin Xu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China.
| | - Shaopeng Chen
- Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China
| | - Lijun Wu
- Information Materials and Intelligent Sensing Laboratory of Anhui Province, Institutes of Physical Science and Information Technology, Anhui University, Hefei, Anhui 230601, China; Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
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13
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Emmert H, Baurecht H, Thielking F, Stölzl D, Rodriguez E, Harder I, Proksch E, Weidinger S. Stratum corneum lipidomics analysis reveals altered ceramide profile in atopic dermatitis patients across body sites with correlated changes in skin microbiome. Exp Dermatol 2020; 30:1398-1408. [PMID: 32885529 DOI: 10.1111/exd.14185] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Revised: 07/24/2020] [Accepted: 08/24/2020] [Indexed: 12/24/2022]
Abstract
BACKGROUND Atopic dermatitis (AD) is driven by the interplay between a dysfunctional epidermal barrier and a skewed cutaneous immune dysregulation. As part of the complex skin barrier dysfunction, abnormalities in lipid organization and microbiome composition have been described. We set out to systematically investigate the composition of the stratum corneum lipidome, skin microbiome and skin physiology parameters at three different body sites in patients with AD and healthy volunteers. METHODS We analysed tape strips from different body areas obtained from 10 adults with AD and 10 healthy volunteers matched for FLG mutation status for 361 skin lipid species using the Metabolon mass spectrometry platform. 16S rRNA data were available from all probands. RESULTS Our study showed that the lipid composition differs significantly between body sites and between AD patients and healthy individuals. Ceramide species NS was significantly higher in AD patients compared to healthy volunteers and was also higher in AD patients with a FLG mutation compared to AD patients without a FLG mutation. The correlation analysis of skin lipid alterations with the microbiome showed that Staphylococcus colonization in AD is positively correlated with ceramide subspecies AS, ADS, NS and NDS. CONCLUSION This is the first study to reveal site-specific lipid alterations and correlations with the skin microbiome in AD.
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Affiliation(s)
- Hila Emmert
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Hansjörg Baurecht
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany.,Department of Epidemiology and Preventive Medicine, University of Regensburg, Regensburg, Germany
| | - Frederieke Thielking
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Dora Stölzl
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Elke Rodriguez
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Inken Harder
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Ehrhardt Proksch
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
| | - Stephan Weidinger
- Department of Dermatology, Allergology and Venereology, University Hospital Schleswig-Holstein, Kiel, Germany
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Exogenous Liposomal Ceramide-C6 Ameliorates Lipidomic Profile, Energy Homeostasis, and Anti-Oxidant Systems in NASH. Cells 2020; 9:cells9051237. [PMID: 32429478 PMCID: PMC7290333 DOI: 10.3390/cells9051237] [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: 04/10/2020] [Revised: 05/05/2020] [Accepted: 05/13/2020] [Indexed: 02/07/2023] Open
Abstract
In non-alcoholic steatohepatitis (NASH), many lines of investigation have reported a dysregulation in lipid homeostasis, leading to intrahepatic lipid accumulation. Recently, the role of dysfunctional sphingolipid metabolism has also been proposed. Human and animal models of NASH have been associated with elevated levels of long chain ceramides and pro-apoptotic sphingolipid metabolites, implicated in regulating fatty acid oxidation and inflammation. Importantly, inhibition of de novo ceramide biosynthesis or knock-down of ceramide synthases reverse some of the pathology of NASH. In contrast, cell permeable, short chain ceramides have shown anti-inflammatory actions in multiple models of inflammatory disease. Here, we investigated non-apoptotic doses of a liposome containing short chain C6-Ceramide (Lip-C6) administered to human hepatic stellate cells (hHSC), a key effector of hepatic fibrogenesis, and an animal model characterized by inflammation and elevated liver fat content. On the basis of the results from unbiased liver transcriptomic studies from non-alcoholic fatty liver disease patients, we chose to focus on adenosine monophosphate activated kinase (AMPK) and nuclear factor-erythroid 2-related factor (Nrf2) signaling pathways, which showed an abnormal profile. Lip-C6 administration inhibited hHSC proliferation while improving anti-oxidant protection and energy homeostasis, as indicated by upregulation of Nrf2, activation of AMPK and an increase in ATP. To confirm these in vitro data, we investigated the effect of a single tail-vein injection of Lip-C6 in the methionine-choline deficient (MCD) diet mouse model. Lip-C6, but not control liposomes, upregulated phospho-AMPK, without inducing liver toxicity, apoptosis, or exacerbating inflammatory signaling pathways. Alluding to mechanism, mass spectrometry lipidomics showed that Lip-C6-treatment reversed the imbalance in hepatic phosphatidylcholines and diacylglycerides species induced by the MCD-fed diet. These results reveal that short-term Lip-C6 administration reverses energy/metabolic depletion and increases protective anti-oxidant signaling pathways, possibly by restoring homeostatic lipid function in a model of liver inflammation with fat accumulation.
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Afşar E, Kırımlıoglu E, Çeker T, Yılmaz Ç, Demir N, Aslan M. Effect of ER stress on sphingolipid levels and apoptotic pathways in retinal pigment epithelial cells. Redox Biol 2020; 30:101430. [PMID: 31978676 PMCID: PMC6976939 DOI: 10.1016/j.redox.2020.101430] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Revised: 12/30/2019] [Accepted: 01/10/2020] [Indexed: 12/31/2022] Open
Abstract
Background We aimed to determine sphingolipid levels and examine apoptotic pathways in human retinal pigment epithelial cells (ARPE-19) undergoing endoplasmic reticulum (ER) stress. Methods Cells were treated with tunicamycin (TM) to induce ER stress and tauroursodeoxycholic acid (TUDCA), an ER stress inhibitor, was administered to decrease cytotoxicity. Cell viability was measured by MTT assay. Levels of C16–C24 sphingomyelins (SM) and C16–C24 ceramides (CERs) were determined by LC-MS/MS. Glucose-regulated protein 78-kd (GRP78) and nuclear factor kappa-b subunit 1 (NFκB1) gene expressions were evaluated by quantitative PCR analysis, while GRP 78, NF-κB p65, cleaved caspase-3 and caspase-12 protein levels were assesed by immunofluorescence. Ceramide-1-phosphate (C1P) levels were determined by immunoassay, while caspase −3 and −12 activity in cell lysates were measured via a fluorometric method. Results Induction of ER stress in TM treated groups were confirmed by significantly increased mRNA and protein levels of GRP78. TM significantly decreased cell viability compared to controls. Treatment with TUDCA along with TM significantly increased cell viability compared to the TM group. A significant increase was observed in C22–C24 CERs, C1P, caspase-3, caspase-12, NFκB1 mRNA and NF-κB p65 protein levels in cells treated with TM compared to controls. Administration of TUDCA lead to a partial decrease in GRP78 expression, NFκB1 mRNA, NF-κB p65 protein, C22–C24 CERs and C1P levels along with a decrease in caspase-3 and -12 activity. Conclusions The results of this study reveal the presence of increased long chain CERs, C1P and apoptotic markers in retinal cells undergoing ER stress.
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Affiliation(s)
- Ebru Afşar
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
| | - Esma Kırımlıoglu
- Department of Histology, Akdeniz University Faculty of Medicine, Antalya, Turkey.
| | - Tuğçe Çeker
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
| | - Çağatay Yılmaz
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
| | - Necdet Demir
- Department of Histology, Akdeniz University Faculty of Medicine, Antalya, Turkey.
| | - Mutay Aslan
- Department of Medical Biochemistry, Akdeniz University Faculty of Medicine, Antalya, Turkey.
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Yang H, Song Z, Hong D. CRBN knockdown mitigates lipopolysaccharide-induced acute lung injury by suppression of oxidative stress and endoplasmic reticulum (ER) stress associated NF-κB signaling. Biomed Pharmacother 2019; 123:109761. [PMID: 31865141 DOI: 10.1016/j.biopha.2019.109761] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2019] [Revised: 11/17/2019] [Accepted: 11/29/2019] [Indexed: 12/15/2022] Open
Abstract
Acute lung injury (ALI) is a common clinical disorder, resulting in substantial health problems in the world. However, the molecular mechanism that contributes to ALI is still unclear. Cereblon (CRBN) has recently been identified as a target for immunomodulatory drugs, playing a critical role in regulating various cellular processes. In the study, we attempted to explore the effects of CRBN on the progression of lipopolysaccharide (LPS)-induced ALI. First, we found that CRBN expression was markedly up-regulated in lung tissues of LPS-challenged mice. Our results suggested that CRBN knockdown mice exhibited better survival rate after LPS challenge, accompanied with improved histological alterations. Further, CRBN decrease effectively ameliorated pulmonary injury by reducing lung wet/dry (W/D) ratio and protein levels, neutrophil infiltration, myeloperoxidase (MPO) and lactate dehydrogenase (LDH) levels. In addition, LPS-triggered inflammation in lung tissues was markedly alleviated in CRBN knockdown mice by reducing the pro-inflammatory cytokines through the inactivation of nuclear factor-κB (NF-κB) signaling. Moreover, CRBN knockdown mice exhibited alleviated oxidative stress by promoting nuclear factor-erythroid 2 related factor 2 (Nrf-2)/heme oxygenase-1 (HO-1) signaling. ER stress stimulated by LPS in pulmonary tissues was significantly alleviated by CRBN knockdown through reducing the expression of ER stress associated signals, including CCAAT/Enhancer-Binding Protein Homologous Protein (CHOP), glucose-regulated protein 78 (GRP78), XBP-1, activating transcription factor (ATF)-4, ATF-6 and phosphorylated eukaryotic initiation factor 2 on Ser51 of the α subunit (eIF2α). The protective effects of CRBN knockdown against ALI were verified in LPS-incubated human pulmonary epithelial cells. Importantly, we found that CRBN knockdown-ameliorated inflammatory response was markedly abrogated by the pre-treatment of Nrf-2 inhibitor and ER stress activator, suggesting that CRBN-regulated inflammation in ALI was partly through the meditation of reactive oxygen species (ROS) generation and endoplasmic reticulum (ER) stress. In conclusion, our study firstly provided a support that CRBN decrease effectively protected LPS-induced ALI against inflammatory response mainly through the repression of oxidative stress and ER stress.
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Affiliation(s)
- Huobao Yang
- Department of Critical Care Medicine, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital , Fuzhou, Fujian 350001, China
| | - Zhen Song
- Department of Critical Care Medicine, Shandong Yuncheng County Chinese Medicine Hospital, Yuncheng County, Shandong Province, 274700, China
| | - Donghuang Hong
- Department of Critical Care Medicine, Shengli Clinical Medical College of Fujian Medical University, Fujian Provincial Hospital , Fuzhou, Fujian 350001, China.
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Jo YD, Kim J, Choung SY. Protective effects of quercetin-3-O-α-l-arabinopyranoside against UVA induced apoptosis via regulating inflammatory pathways in ARPE-19 cells and Balb/c mice. J Funct Foods 2019. [DOI: 10.1016/j.jff.2019.103541] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
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Ceramide Domains in Health and Disease: A Biophysical Perspective. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1159:79-108. [DOI: 10.1007/978-3-030-21162-2_6] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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19
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Xiang XJ, Song L, Deng XJ, Tang Y, Min Z, Luo B, Wen QX, Li KY, Chen J, Ma YL, Zhu BL, Yan Z, Chen GJ. Mitochondrial methionine sulfoxide reductase B2 links oxidative stress to Alzheimer's disease-like pathology. Exp Neurol 2019; 318:145-156. [DOI: 10.1016/j.expneurol.2019.05.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 04/10/2019] [Accepted: 05/08/2019] [Indexed: 01/25/2023]
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20
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Simón MV, Prado Spalm FH, Vera MS, Rotstein NP. Sphingolipids as Emerging Mediators in Retina Degeneration. Front Cell Neurosci 2019; 13:246. [PMID: 31244608 PMCID: PMC6581011 DOI: 10.3389/fncel.2019.00246] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2019] [Accepted: 05/17/2019] [Indexed: 12/12/2022] Open
Abstract
The sphingolipids ceramide (Cer), sphingosine-1-phosphate (S1P), sphingosine (Sph), and ceramide-1-phosphate (C1P) are key signaling molecules that regulate major cellular functions. Their roles in the retina have gained increasing attention during the last decade since they emerge as mediators of proliferation, survival, migration, neovascularization, inflammation and death in retina cells. As exacerbation of these processes is central to retina degenerative diseases, they appear as crucial players in their progression. This review analyzes the functions of these sphingolipids in retina cell types and their possible pathological roles. Cer appears as a key arbitrator in diverse retinal pathologies; it promotes inflammation in endothelial and retina pigment epithelium (RPE) cells and its increase is a common feature in photoreceptor death in vitro and in animal models of retina degeneration; noteworthy, inhibiting Cer synthesis preserves photoreceptor viability and functionality. In turn, S1P acts as a double edge sword in the retina. It is essential for retina development, promoting the survival of photoreceptors and ganglion cells and regulating proliferation and differentiation of photoreceptor progenitors. However, S1P has also deleterious effects, stimulating migration of Müller glial cells, angiogenesis and fibrosis, contributing to the inflammatory scenario of proliferative retinopathies and age related macular degeneration (AMD). C1P, as S1P, promotes photoreceptor survival and differentiation. Collectively, the expanding role for these sphingolipids in the regulation of critical processes in retina cell types and in their dysregulation in retina degenerations makes them attractive targets for treating these diseases.
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Affiliation(s)
- M Victoria Simón
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento De Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), Argentine National Research Council (CONICET), Bahía Blanca, Argentina
| | - Facundo H Prado Spalm
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento De Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), Argentine National Research Council (CONICET), Bahía Blanca, Argentina
| | - Marcela S Vera
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento De Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), Argentine National Research Council (CONICET), Bahía Blanca, Argentina
| | - Nora P Rotstein
- Instituto de Investigaciones Bioquímicas de Bahía Blanca (INIBIBB), Departamento De Biología, Bioquímica y Farmacia, Universidad Nacional del Sur (UNS), Argentine National Research Council (CONICET), Bahía Blanca, Argentina
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Cheng Z, Yao W, Zheng J, Ding W, Wang Y, Zhang T, Zhu L, Zhou F. A derivative of betulinic acid protects human Retinal Pigment Epithelial (RPE) cells from cobalt chloride-induced acute hypoxic stress. Exp Eye Res 2018; 180:92-101. [PMID: 30578788 DOI: 10.1016/j.exer.2018.12.011] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2018] [Revised: 12/13/2018] [Accepted: 12/18/2018] [Indexed: 02/05/2023]
Abstract
The Retinal Pigment Epithelium (RPE) is a monolayer of cells located above the choroid. It mediates human visual cycle and nourishes photoreceptors. Hypoxia-induced oxidative stress to RPE is a vital cause of retinal degeneration such as the Age-related Macular Degeneration. Most of these retinal diseases are irreversible with no efficient treatment, therefore protecting RPE cells from hypoxia stress is an important way to prevent or slow down the progression of retinal degeneration. Betulinic acid (BA) and betulin (BE) are pentacyclic triterpenoids with anti-oxidative property, but little is known about their effect on RPE cells. We investigated the protective effect of BA, BE and their derivatives against cobalt chloride-induced hypoxia stress in RPE cells. Human ARPE-19 cells were exposed to BA, BE and their eighteen derivatives (named as H3H20) that we customized through replacing moieties at C3 and C28 positions. We found that cobalt chloride reduced cell viability, increased Reactive Oxygen Species (ROS) production as well as induced apoptosis and necrosis in ARPE-19 cells. Interestingly, the pretreatment of 3-O-acetyl-glycyl- 28-O-glycyl-betulinic acid effectively protected cells from acute hypoxia stress induced by cobalt chloride. Our immunoblotting results suggested that this derivative attenuated the cobalt chloride-induced activation of Akt, Erk and JNK pathways. All findings were further validated in human primary RPE cells. In summary, this BA derivate has protective effect against the acute hypoxic stress in human RPE cells and may be developed into a candidate agent effective in the prevention of prevalent retinal diseases.
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Affiliation(s)
- Zhengqi Cheng
- School of Pharmacy, The University of Sydney, NSW, 2006, Australia
| | - Wenjuan Yao
- School of Pharmacy, Nantong University, Nantong, Jiangsu Province, China
| | - Jian Zheng
- Center for Bioactive Products, Northeast Forestry University/Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Harbin, 150040, China
| | - Weimin Ding
- School of Chemical and Environmental Engineering, Harbin University of Science and Technology, Harbin, 150080, Heilongjiang, China
| | - Yang Wang
- Center for Bioactive Products, Northeast Forestry University/Key Laboratory of Saline-alkali Vegetation Ecology Restoration, Ministry of Education, Harbin, 150040, China
| | - Ting Zhang
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia; State Key Laboratory of Biotherapy and Cancer Center, Collaborative Innovation Center for Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Ling Zhu
- Save Sight Institute, The University of Sydney, Sydney, NSW, 2000, Australia
| | - Fanfan Zhou
- School of Pharmacy, The University of Sydney, NSW, 2006, Australia.
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22
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Sugano E, Edwards G, Saha S, Wilmott LA, Grambergs RC, Mondal K, Qi H, Stiles M, Tomita H, Mandal N. Overexpression of acid ceramidase (ASAH1) protects retinal cells (ARPE19) from oxidative stress. J Lipid Res 2018; 60:30-43. [PMID: 30413652 DOI: 10.1194/jlr.m082198] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2017] [Revised: 10/26/2018] [Indexed: 01/08/2023] Open
Abstract
Over 11 million people in the United States alone have some form of age-related macular degeneration (AMD). Oxidative stress, cell death, and the degeneration of retinal pigment epithelial (RPE) cells contribute to AMD pathology. Recent evidence suggests that ceramide (Cer), a cellular sphingolipid mediator that acts as a second messenger to induce apoptosis, might play a role in RPE cell death. The lysosomal breakdown of Cer by acid ceramidase [N-acylsphingosine amidohydrolase (ASAH)1] into sphingosine (Sph) is the major source for Sph 1-phosphate production, which has an opposing role to Cer and provides cytoprotection. Here, we investigated the role of Cer in human RPE-derived ARPE19 cells under hydrogen peroxide-induced oxidative stress, and show that Cer and hexosyl-Cer levels increase in the oxidatively stressed ARPE19 cells, which can be prevented by overexpression of lysosomal ASAH1. This study demonstrates that oxidative stress generates sphingolipid death mediators in retinal cells and that induction of ASAH1 could rescue retinal cells from oxidative stress by hydrolyzing excess Cers.
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Affiliation(s)
- Eriko Sugano
- Division of Science and Engineering, Iwate University, Morioka 020-8551, Japan
| | - Genea Edwards
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163
| | - Saikat Saha
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163
| | - Lynda A Wilmott
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163
| | - Richard C Grambergs
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163
| | - Koushik Mondal
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163
| | - Hui Qi
- Department of Ophthalmology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104
| | - Megan Stiles
- Department of Ophthalmology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104
| | - Hiroshi Tomita
- Division of Science and Engineering, Iwate University, Morioka 020-8551, Japan
| | - Nawajes Mandal
- Departments of Ophthalmology University of Tennessee Health Science Center, Memphis, TN 38163 .,Department of Ophthalmology, University of Oklahoma Health Science Center, Oklahoma City, OK 73104.,Anatomy and Neurobiology, University of Tennessee Health Science Center, Memphis, TN 38163
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NKILA inhibition protects retinal pigment epithelium cells from hypoxia by facilitating NFκB activation. Biochem Biophys Res Commun 2018; 503:3134-3141. [PMID: 30144973 DOI: 10.1016/j.bbrc.2018.08.105] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2018] [Accepted: 08/16/2018] [Indexed: 01/08/2023]
Abstract
Sustained retinal hypoxia causes injuries to retinal pigment epithelium (RPE) cells. We studied expression and potential functions of nuclear factor-κB (NFκB) Interacting LncRNA (NKILA) in hypoxia-treated RPE cells. Hypoxia induced NKILA expression, NKILA-IκBα association and NFκB activation in ARPE-19 cells and primary human RPE cells. shRNA-mediated knockdown of NKILA facilitated NFκB activation, inhibiting RPE cell death and apoptosis. Conversely, exogenous overexpression of NKILA blocked hypoxia-induced NFκB activation, thereby exacerbating RPE cell apoptosis. Further studies show that hypoxia downregulated microRNA-103 (miR-103), the anti-NKILA microRNA, in RPE cells. Transfection of miR-103 mimic blocked hypoxia-induced NKILA expression to significantly boost NFκB activation, protecting RPE cells from hypoxia. Collectively, we conclude that hypoxia-induced NKILA expression negatively regulates NFκB to promote RPE cell death. Conversely, NKILA inhibition protects RPE cells from hypoxia by facilitating NFκB activation.
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Protective Effect of Melatonin against Oxidative Stress-Induced Apoptosis and Enhanced Autophagy in Human Retinal Pigment Epithelium Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2018; 2018:9015765. [PMID: 30174783 PMCID: PMC6098907 DOI: 10.1155/2018/9015765] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 06/01/2018] [Accepted: 06/06/2018] [Indexed: 12/20/2022]
Abstract
Age-related macular degeneration (AMD) affects the retinal macula and results in loss of vision, and AMD is the primary cause of blindness and severe visual impairment among elderly people worldwide. AMD is characterized by the accumulation of drusen in the Bruch's membrane and dysfunction of retinal pigment epithelial (RPE) cells and photoreceptors. The pathogenesis of AMD remains unclear, and no effective treatment exists. Accumulating evidence indicates that oxidative stress plays a critical role in RPE cell degeneration and AMD. Melatonin is an antioxidant that scavenges free radicals, and it has anti-inflammatory, antitumor, and antiangiogenic effects. This study investigated the antioxidative, antiapoptotic, and autophagic effects of melatonin on oxidative damage to RPE cells. We used hydrogen peroxide (H2O2) to stimulate reactive oxygen species production to cause cell apoptosis in ARPE-19 cell lines. Our findings revealed that treatment with melatonin significantly inhibited H2O2-induced RPE cell damage, decreased the apoptotic rate, increased the mitochondrial membrane potential, and increased the autophagy effect. Furthermore, melatonin reduced the Bax/Bcl-2 ratio and the expression levels of the apoptosis-associated proteins cytochrome c and caspase 7. Additionally, melatonin upregulated the expression of the autophagy-related proteins LC3-II and Beclin-1 and downregulated the expression of p62. Thus, melatonin's effects on autophagy and apoptosis can protect against H2O2-induced oxidative damage in human RPE cells. Melatonin may have multiple protective effects on human RPE cells against H2O2-induced oxidative damage.
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Li XM, Huang D, Yu Q, Yang J, Yao J. Neuroligin-3 protects retinal cells from H2O2-induced cell death via activation of Nrf2 signaling. Biochem Biophys Res Commun 2018; 502:166-172. [DOI: 10.1016/j.bbrc.2018.05.141] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 05/19/2018] [Indexed: 01/12/2023]
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Berberine Protects Human Retinal Pigment Epithelial Cells from Hydrogen Peroxide-Induced Oxidative Damage through Activation of AMPK. Int J Mol Sci 2018; 19:ijms19061736. [PMID: 29895743 PMCID: PMC6032421 DOI: 10.3390/ijms19061736] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2017] [Revised: 02/23/2018] [Accepted: 03/12/2018] [Indexed: 12/12/2022] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of central vision loss in the elderly with less effective treatment, especially for dry AMD (90% of AMD). Although the etiology of this disease is not well elucidated, increasing evidences indicate that excessive reactive oxygen species (ROS) impairing the physiological functions of retinal pigment epithelium (RPE) cells may be one of the main causes. Therefore, it could be a great strategy to find some drugs that can effectively protect RPE cells from oxidative damage which is desired to treat and slow the process of AMD. In the present study, a well-known traditional Chinese medicine berberine (BBR) was found to suppress hydrogen peroxide (H2O2)-induced oxidative damage in D407 cells, a human RPE cell line. Pre-treatment of D407 cells with BBR significantly suppressed H2O2-induced cell apoptosis by restoring abnormal changes in nuclear morphology, preventing the decline of mitochondrial membrane potential, reducing lactate dehydrogenase release and inhibiting caspase 3/7 activities induced by H2O2. Western blot analysis showed that BBR was able to stimulate the phosphorylation/activation of AMPK in a time- and dose-dependent manner in D407 cells, while treatment of cells with AMPK pathway inhibitor Compound C, or knockdown of the AMPK by specific siRNA blocked the effect of BBR. Similar results were obtained in primary cultured human RPE cells. Taken together, these results demonstrated that BBR was able to protect RPE cells against oxidative stress via the activation of AMPK pathway. Our findings also indicate the potential application of BBR in AMD treatment.
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Li XF, Liu XM, Huang DR, Cao HJ, Wang JY. PF-06409577 activates AMPK signaling to protect retinal pigment epithelium cells from UV radiation. Biochem Biophys Res Commun 2018; 501:293-299. [DOI: 10.1016/j.bbrc.2018.05.003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2018] [Accepted: 05/02/2018] [Indexed: 01/01/2023]
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P2RX7-MAPK1/2-SP1 axis inhibits MTOR independent HSPB1-mediated astroglial autophagy. Cell Death Dis 2018; 9:546. [PMID: 29749377 PMCID: PMC5945848 DOI: 10.1038/s41419-018-0586-x] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 04/04/2018] [Accepted: 04/12/2018] [Indexed: 12/31/2022]
Abstract
Recently, we have reported that heat shock protein B1 (HSPB1) and purinergic receptor P2X7 (P2RX7) are involved in astroglial autophagy (clasmatodendrosis), following status epilepticus (SE). However, the underlying mechanisms of astroglial autophagy have not been completely established. In the present study, we found that the lacking of P2rx7 led to prolonged astroglial HSPB1 induction due to impaired mitogen-activated protein kinase 1/2 (MAPK1/2)-mediated specificity protein 1 (SP1) phosphorylation, following kainic acid-induced SE. Subsequently, the upregulated HSPB1 itself evoked ER stress and exerted protein kinase AMP-activated catalytic subunit alpha 1 (PRKAA1, AMPK1)/unc-51 such as autophagy activating kinase 1 (ULK1)- and AKT serine/threonine kinase 1 (AKT1)/glycogen synthase kinase 3 beta (GSK3B)/SH3-domain GRB2-like B1 (SH3GLB1)-mediated autophagic pathways, independent of mechanistic target of rapamycin (MTOR) activity in astrocytes. These findings provide a novel purinergic suppression mechanism to link chaperone expression to autophagy in astrocytes. Therefore, we suggest that P2RX7 may play an important role in the regulation of autophagy by the fine-tuning of HSPB1 expression.
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Yang K, Nong K, Gu Q, Dong J, Wang J. Discovery of N-hydroxy-3-alkoxybenzamides as direct acid sphingomyelinase inhibitors using a ligand-based pharmacophore model. Eur J Med Chem 2018; 151:389-400. [PMID: 29649738 DOI: 10.1016/j.ejmech.2018.03.065] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 03/20/2018] [Accepted: 03/21/2018] [Indexed: 10/17/2022]
Abstract
Acid sphingomyelinase (ASM) has been shown to be involved in many physiological processes, emerging to be a promising drug target. In this study, we constructed a ligand-based pharmacophore model of ASM inhibitors and applied this model to optimize the lead compound α-mangostin, a known inhibitor of ASM. 23 compounds were designed and evaluated in vitro for ASM inhibition, of these, 10 compounds were found to be more potent than α-mangostin. This high hit ratio confirmed that the presented model is very effective and practical. The most potent hit, 1c, was found to selectively and competitively inhibit the enzyme and inhibit the generation of ceramide in a dose-dependent manner. Furthermore, 1c showed favorable anti-apoptosis and anti-inflammatory activity. Interactions with key residues and the Zn2+ cofactor of 1c were found by docking simulation. These results provide promising leads and important guidance for further development of efficient ASM inhibitors and drug candidates.
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Affiliation(s)
- Kan Yang
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Keyi Nong
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China
| | - Qinlan Gu
- Senior Vocational School, China Pharmaceutical University, Nanjing, 210009, China
| | - Jibin Dong
- Department of Biochemistry, School of Pharmacy, Fudan University, Shanghai, 201203, China.
| | - Jinxin Wang
- Jiangsu Key Laboratory of Drug Design and Optimization, Department of Medicinal Chemistry, School of Pharmacy, China Pharmaceutical University, Nanjing, 210009, China.
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Cai S, Li Y, Bai JY, Zhang ZQ, Wang Y, Qiao YB, Zhou XZ, Yang B, Tian Y, Cao C. Gαi3 nuclear translocation causes irradiation resistance in human glioma cells. Oncotarget 2018; 8:35061-35068. [PMID: 28456783 PMCID: PMC5471034 DOI: 10.18632/oncotarget.17043] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2017] [Accepted: 03/30/2017] [Indexed: 12/27/2022] Open
Abstract
We have previously shown that Gαi3 is elevated in human glioma, mediating Akt activation and cancer cell proliferation. Here, we imply that Gαi3 could also be important for irradiation resistance. In A172 human glioma cells, Gαi3 knockdown (by targeted shRNAs) or dominant-negative mutation significantly potentiated irradiation-induced cell apoptosis. Reversely, forced over-expression of wild-type or constitutively-active Gαi3 inhibited irradiation-induced A172 cell apoptosis. Irradiation in A172 cells induced Gαi3 translocation to cell nuclei and association with local protein DNA-dependent protein kinase (DNA-PK) catalytic subunit. This association was important for DNA damage repair. Gαi3 knockdown, depletion (using Gαi3 knockout MEFs) or dominant-negative mutation potentiated irradiation-induced DNA damages. On the other hand, expression of the constitutively-active Gαi3 in A172 cells inhibited DNA damage by irradiation. Together, these results indicate a novel function of Gαi3 in irradiation-resistance in human glioma cells.
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Affiliation(s)
- Shang Cai
- Department of Radiotherapy and Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Ya Li
- Institute of Neuroscience, Soochow University, Suzhou, China
| | - Jin-Yu Bai
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Zhi-Qing Zhang
- Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yin Wang
- Institute of Neuroscience, Soochow University, Suzhou, China
| | - Yin-Biao Qiao
- Department of Surgery, The Third Hospital affiliated to Soochow University
| | - Xiao-Zhong Zhou
- Department of Orthopedics, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Bo Yang
- Department of Surgery, The Third Hospital affiliated to Soochow University
| | - Ye Tian
- Department of Radiotherapy and Oncology, The Second Affiliated Hospital of Soochow University, Suzhou, China
| | - Cong Cao
- Institute of Neuroscience, Soochow University, Suzhou, China
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31
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Tang CZ, Li KR, Yu Q, Jiang Q, Yao J, Cao C. Activation of Nrf2 by Ginsenoside Rh3 protects retinal pigment epithelium cells and retinal ganglion cells from UV. Free Radic Biol Med 2018; 117:238-246. [PMID: 29427790 DOI: 10.1016/j.freeradbiomed.2018.02.001] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/11/2018] [Accepted: 02/02/2018] [Indexed: 12/20/2022]
Abstract
Excessive Ultra-violet (UV) radiation shall induce damages to resident retinal pigment epithelium (RPE) cells (RPEs) and retinal ganglion cells (RGCs). Here we tested the potential activity of Ginsenoside Rh3 ("Rh3") against the process. In cultured human RPEs and RGCs, pretreatment with Rh3 inhibited UV-induced reactive oxygen species (ROS) production and following apoptotic/non-apoptotic cell death. Rh3 treatment in retinal cells induced nuclear-factor-E2-related factor 2 (Nrf2) activation, which was evidenced by Nrf2 protein stabilization and its nuclear translocation, along with transcription of antioxidant responsive element (ARE)-dependent genes (HO1, NOQ1 and GCLC). Nrf2 knockdown by targeted-shRNA almost abolished Rh3-induced retinal cell protection against UV. Further studies found that Rh3 induced microRNA-141 ("miR-141") expression, causing downregulation of its targeted gene Keap1 in RPEs and RGCs. On the other hand, Rh3-induced Nrf2 activation and retinal cell protection were largely attenuated by the miR-141's inhibitor, antagomiR-141. In vivo, intravitreal injection of Rh3 inhibited retinal dysfunction by light damage in mice. Rh3 intravitreal injection also induced miR-141 expression, Keap1 downregulation and Nrf2 activation in mouse retinas. We conclude that Rh3 protects retinal cells from UV via activating Nrf2 signaling.
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Affiliation(s)
- Chun-Zhou Tang
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China; Ophthalmology Department, Jiangsu Jiangyin people's Hospital, Jiangyin, China
| | - Ke-Ran Li
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
| | - Qing Yu
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
| | - Qin Jiang
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China.
| | - Jin Yao
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China.
| | - Cong Cao
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China; Jiangsu Key Laboratory of Neuropsychiatric Diseases and Institute of Neuroscience, Soochow University, Suzhou, China; Center of Translational Medicine, The First People Hospital of Zhangjiagang City, Soochow University, Suzhou, China; North District, The Municipal Hospital of Suzhou, Suzhou, China.
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32
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Gong YQ, Huang W, Li KR, Liu YY, Cao GF, Cao C, Jiang Q. SC79 protects retinal pigment epithelium cells from UV radiation via activating Akt-Nrf2 signaling. Oncotarget 2018; 7:60123-60132. [PMID: 27517753 PMCID: PMC5312373 DOI: 10.18632/oncotarget.11164] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2016] [Accepted: 07/20/2016] [Indexed: 12/11/2022] Open
Abstract
Excessive Ultra-violet (UV) radiation causes oxidative damages and apoptosis in retinal pigment epithelium (RPE) cells. Here we tested the potential activity of SC79, a novel small molecule activator of Akt, against the process. We showed that SC79 activated Akt in primary and established (ARPE-19 line) RPE cells. It protected RPE cells from UV damages possibly via inhibiting cell apoptosis. Akt inhibition, via an Akt specific inhibitor (MK-2206) or Akt1 shRNA silence, almost abolished SC79-induced RPE cytoprotection. Further studies showed that SC79 activated Akt-dependent NF-E2-related factor 2 (Nrf2) signaling and inhibited UV-induced oxidative stress in RPE cells. Reversely, Nrf2 shRNA knockdown or S40T mutation attenuated SC79-induced anti-UV activity. For the in vivo studies, we showed that intravitreal injection of SC79 significantly protected mouse retina from light damages. Based on these results, we suggest that SC79 protects RPE cells from UV damages possibly via activating Akt-Nrf2 signaling axis.
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Affiliation(s)
- Yi-Qing Gong
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China.,Ophthalmology Department, Zhenjiang First People's Hospital, Zhenjiang, China
| | - Wei Huang
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
| | - Ke-Ran Li
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
| | - Yuan-Yuan Liu
- Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Guo-Fan Cao
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
| | - Cong Cao
- Institute of Neuroscience, Soochow University, Suzhou, Jiangsu, China
| | - Qin Jiang
- The Affiliated Eye Hospital of Nanjing Medical University, Nanjing, China
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Hu H, Hao L, Tang C, Zhu Y, Jiang Q, Yao J. Activation of KGFR-Akt-mTOR-Nrf2 signaling protects human retinal pigment epithelium cells from Ultra-violet. Biochem Biophys Res Commun 2018; 495:2171-2177. [DOI: 10.1016/j.bbrc.2017.12.078] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2017] [Accepted: 12/14/2017] [Indexed: 11/24/2022]
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Synthesis and evaluation of xanthone derivatives as acid sphingomyelinase inhibitors: potential treatment for UV-induced skin damage. Future Med Chem 2017; 9:1887-1898. [DOI: 10.4155/fmc-2017-0102] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022] Open
Abstract
Aim: ASM, which hydrolyzes sphingomyelin into ceramide, is recognized as a therapeutic target for UV-induced skin damage. Direct inhibitors for this enzyme are rare. Here we synthesized several series of 1,3,6,7-tetrahydroxy-xanthone derivatives as novel ASM inhibitors. Results: Several compounds were more potent than the lead compound, among which 5b was found competitively inhibiting the enzyme and dose-dependently reducing ceramide generation. Furthermore, 5b and 5c showed excellent protective effect to skin keratinocytes against UV. Quantitative structure–activity relationship investigation revealed detail relationships between molecular structure and biological activity. Insight into the binding mode was precisely illuminated by molecule docking. Conclusion: This work would provide fresh ideas and strong supports for further development of ASM inhibitors and drug candidates for skin damage.
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MIND4-17 protects retinal pigment epithelium cells and retinal ganglion cells from UV. Oncotarget 2017; 8:89793-89801. [PMID: 29163788 PMCID: PMC5685709 DOI: 10.18632/oncotarget.21131] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 09/03/2017] [Indexed: 01/01/2023] Open
Abstract
Nrf2 activation would efficiently protect retinal cells from UV radiation (UVR). Recent studies have developed a Nrf2-targeting thiazole-containing compound MIND4-17, which activates Nrf2 through blocking its association with Keap1. In the current study, we demonstrated that pretreatment with MIND4-17 efficiently protected retinal pigment epithelium (RPE) cells (RPEs) and retinal ganglion cells (RGCs) from UVR. UVR-induced apoptosis in the retinal cells was also largely attenuated by MIND4-17 pretreatment. MIND4-17 presumably separated Nrf2 from Keap1, allowing its stabilization and accumulation in retinal cells, which then translocated to cell nuclei and promoted transcription of ARE-dependent anti-oxidant genes, including HO1, NQO1 and GCLM. Significantly, shRNA-mediated knockdown of Nrf2 almost completely abolished MIND4-17-induced cytoprotection against UVR. Further studies showed that MIND4-17 largely ameliorated UVR-induced ROS production, lipid peroxidation and DNA damages in RPEs and RGCs. Together, MIND4-17 protects retinal cells from UVR by activating Nrf2 signaling.
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Yang B, Xu QY, Guo CY, Huang JW, Wang SM, Li YM, Tu Y, He L, Bi ZG, Ji C, Cheng B. MHY1485 ameliorates UV-induced skin cell damages via activating mTOR-Nrf2 signaling. Oncotarget 2017; 8:12775-12783. [PMID: 28061443 PMCID: PMC5355053 DOI: 10.18632/oncotarget.14299] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Accepted: 12/08/2016] [Indexed: 12/30/2022] Open
Abstract
Ultra Violet (UV)-caused skin cell damage is a main cause of skin cancer. Here, we studied the activity of MHY1485, a mTOR activator, in UV-treated skin cells. In primary human skin keratinocytes, HaCaT keratinocytes and human skin fibroblasts, MHY1485 ameliorated UV-induced cell death and apoptosis. mTOR activation is required for MHY1485-induced above cytoprotective actions. mTOR kinase inhibitors (OSI-027, AZD-8055 and AZD-2014) or mTOR shRNA knockdown almost abolished MHY1485-induced cytoprotection. Further, MHY1485 treatment in skin cells activated mTOR downstream NF-E2-related factor 2 (Nrf2) signaling, causing Nrf2 Ser-40 phosphorylation, stabilization/upregulation and nuclear translocation, as well as mRNA expression of Nrf2-dictated genes. Contrarily, Nrf2 knockdown or S40T mutation almost nullified MHY1485-induced cytoprotection. MHY1485 suppressed UV-induced reactive oxygen species production and DNA single strand breaks in skin keratinocytes and fibroblasts. Together, we conclude that MHY1485 inhibits UV-induced skin cell damages via activating mTOR-Nrf2 signaling.
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Affiliation(s)
- Bo Yang
- Department of Dermatology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Qiu-Yun Xu
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Chun-Yan Guo
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Jin-Wen Huang
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Shu-Mei Wang
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Yong-Mei Li
- Department of Dermatology, Longhua Hospital, Shanghai University of Traditional Chinese Medicine, Shanghai, China
| | - Ying Tu
- Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming, China
| | - Li He
- Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming, China
| | - Zhi-Gang Bi
- Department of Dermatology, BenQ Medical Center, Nanjing Medical University, Nanjing, China
| | - Chao Ji
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
| | - Bo Cheng
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou, China
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miRNA-141 attenuates UV-induced oxidative stress via activating Keap1-Nrf2 signaling in human retinal pigment epithelium cells and retinal ganglion cells. Oncotarget 2017; 8:13186-13194. [PMID: 28061435 PMCID: PMC5355087 DOI: 10.18632/oncotarget.14489] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2016] [Accepted: 12/07/2016] [Indexed: 12/30/2022] Open
Abstract
Activation of NF-E2-related factor 2 (Nrf2) signaling could protect cells from ultra violet (UV) radiation. We aim to provoke Nrf2 activation via downregulating its inhibitor Keap1 by microRNA-141 (“miR-141”). In both human retinal pigment epithelium cells (RPEs) and retinal ganglion cells (RGCs), forced-expression of miR-141 downregulated Keap1, causing Nrf2 stabilization, accumulation and nuclear translocation, which led to transcription of multiple antioxidant-responsive element (ARE) genes (HO1, NOQ1 and GCLC). Further, UV-induced reactive oxygen species (ROS) production and cell death were significantly attenuated in miR-141-expressing RPEs and RGCs. On the other hand, depletion of miR-141 via expressing its inhibitor antagomiR-141 led to Keap1 upregulation and Nrf2 degradation, which aggravated UV-induced death of RPEs and RGCs. Significantly, Nrf2 shRNA knockdown almost abolished miR-141-mediated cytoprotection against UV in RPEs. These results demonstrate that miR-141 targets Keap1 to activate Nrf2 signaling, which protects RPEs and RGCs from UV radiation.
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Zhang H, Li J, Li L, Liu P, Wei Y, Qian Z. Ceramide enhances COX-2 expression and VSMC contractile hyperreactivity via ER stress signal activation. Vascul Pharmacol 2017; 96-98:26-32. [PMID: 28797762 DOI: 10.1016/j.vph.2017.08.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Revised: 06/22/2017] [Accepted: 08/01/2017] [Indexed: 01/15/2023]
Abstract
Ceramide accumulation in blood vessels has been attributed to vascular dysfunction in progressive vascular complications in metabolic diseases. The present study showed that ceramide pretreatment promoted PE-induced vasoconstriction in rat endothelium-denuded vascular rings in a time- and dose-dependent manner. Endoplasmic reticulum (ER) stress inhibitors, 4-PBA and TUDCA, COX-2 inhibitors, Celecoxib and NS398, as well as PGE2 receptor antagonist AH-6809 attenuated ceramide-promoted vascular hyperreactivity. Ceramide promoted the transcriptional and translational expression of COX-2 and BiP in VSMCs, which were blocked by the ER stress inhibitors, 4-PBA and TUDCA. These findings show that ceramide enhances PE-induced vascular smooth muscle constriction by mediation of the ER stress/COX-2/PGE2 pathway. Therapeutic strategies targeted to reducing ER stress and COX-2 activation might be beneficial in attenuating vascular complications. CHEMICAL COMPOUNDS C2-Ceramide (N-acetyl-d-erythro-sphingosine) CID:2662 Tauroursodeoxycholic Acid Sodium (TUDCA) CID:9848818 phenylephrine (PE) CID:6041.
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Affiliation(s)
- Huina Zhang
- Beijing An Zhen Hospital, Capital Medical University, Key Laboratory of Upper Airway Dysfunction-related Cardiovascular Diseases, Beijing Institute of Heart Lung and Blood Vessel Disease, Beijing, China.
| | - Juanfen Li
- Department of Cardiovascular Medicine, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China
| | - Linghai Li
- Department of Anesthesiology, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China
| | - Pingsheng Liu
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Yongxiang Wei
- Beijing An Zhen Hospital, Capital Medical University, Key Laboratory of Upper Airway Dysfunction-related Cardiovascular Diseases, Beijing Institute of Heart Lung and Blood Vessel Disease, Beijing, China
| | - Zongjie Qian
- Department of Cardiovascular Medicine, Affiliated Hospital of Guilin Medical University, Guilin, Guangxi, China.
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The novel cyclophilin D inhibitor compound 19 protects retinal pigment epithelium cells and retinal ganglion cells from UV radiation. Biochem Biophys Res Commun 2017; 487:807-812. [DOI: 10.1016/j.bbrc.2017.04.128] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 04/23/2017] [Indexed: 12/23/2022]
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40
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Zhang Y, Zeng SX, Hao Q, Lu H. Monitoring p53 by MDM2 and MDMX is required for endocrine pancreas development and function in a spatio-temporal manner. Dev Biol 2017; 423:34-45. [PMID: 28118981 DOI: 10.1016/j.ydbio.2017.01.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 01/19/2017] [Accepted: 01/20/2017] [Indexed: 02/06/2023]
Abstract
Although p53 is not essential for normal embryonic development, it plays a pivotal role in many biological and pathological processes, including cell fate determination-dependent and independent events and diseases. The expression and activity of p53 largely depend on its two biological inhibitors, MDM2 and MDMX, which have been shown to form a complex in order to tightly control p53 to an undetectable level during early stages of embryonic development. However, more delicate studies using conditional gene-modification mouse models show that MDM2 and MDMX may function separately or synergistically on p53 regulation during later stages of embryonic development and adulthood in a cell and tissue-specific manner. Here, we report the role of the MDM2/MDMX-p53 pathway in pancreatic islet morphogenesis and functional maintenance, using mouse lines with specific deletion of MDM2 or MDMX in pancreatic endocrine progenitor cells. Interestingly, deletion of MDM2 results in defects of embryonic endocrine pancreas development, followed by neonatal hyperglycemia and lethality, by inducing pancreatic progenitor cell apoptosis and inhibiting cell proliferation. However, unlike MDM2-knockout animals, mice lacking MDMX in endocrine progenitor cells develop normally. But, surprisingly, the survival rate of adult MDMX-knockout mice drastically declines compared to control mice, as blockage of neonatal development of endocrine pancreas by inhibition of cell proliferation and subsequent islet dysfunction and hyperglycemia eventually lead to type 1 diabetes-like disease with advanced diabetic nephropathy. As expected, both MDM2 and MDMX deletion-caused pancreatic defects are completely rescued by loss of p53, verifying the crucial role of the MDM2 and/or MDMX in regulating p53 in a spatio-temporal manner during the development, functional maintenance, and related disease progress of endocrine pancreas. Also, our study suggests a possible mouse model of advanced diabetic nephropathy, which is complementary to other established diabetic models and perhaps useful for the development of anti-diabetes therapies.
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Affiliation(s)
- Yiwei Zhang
- Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA; Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Shelya X Zeng
- Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA; Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Qian Hao
- Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA
| | - Hua Lu
- Department of Biochemistry & Molecular Biology, Tulane University School of Medicine, New Orleans, LA 70112, USA; Tulane Cancer Center, Tulane University School of Medicine, New Orleans, LA 70112, USA.
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41
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Zhu C, Dong Y, Liu H, Ren H, Cui Z. Hesperetin protects against H 2O 2-triggered oxidative damage via upregulation of the Keap1-Nrf2/HO-1 signal pathway in ARPE-19 cells. Biomed Pharmacother 2017; 88:124-133. [PMID: 28103505 DOI: 10.1016/j.biopha.2016.11.089] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 11/15/2016] [Accepted: 11/21/2016] [Indexed: 12/31/2022] Open
Abstract
Age-related macular degeneration (AMD) is an irreversible vision loss disease that primarily results from oxidative stress that causes oxidative damage to the retinal pigment epithelial (RPE) cells. Hesperetin (Hesp) is a common flavanone glycoside compound that has been demonstrated to exhibit a variety of biological and pharmacological properties that include anti-inflammatory and antioxidant properties. The aim of this study is to explore the ability of Hesp to attenuate oxidative damage in hydrogen peroxide (H2O2)-stimulated ARPE-19 cells. The results indicated that Hesp treatment not only increased cell survival but also decreased reactive oxygen species (ROS) generation, whereas these roles were effectively enhanced the superoxide dismutase (SOD) and glutathione (GSH) levels, and reduced malondialdehyde (MDA) formation. Importantly, the level of heme oxygenase-1 (HO-1) expression was increased by Hesp exposure, which resulted in a decrease after the transfection of cells with Nrf2-siRNA. Additionally, further results revealed that Hesp treatment significantly elevated Keap-1 protein expression, Nrf2 nuclear translocation and ARE activities. These observations indicated that Hesp treatment effectively protected against H2O2-induced oxidative damage in ARPE-19 cells by inhibiting cell apoptosis, ROS overproduction and MDA formation as well as enhancing the SOD and GSH levels. The underlying mechanisms may be related to the activation of the Keap1-Nrf2/HO-1 signal pathway, which may provide biological evidence to further encourage the investigation of the protective effect of Hesp in AMD disease.
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Affiliation(s)
- Chao Zhu
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun 130041, China
| | - Yuchen Dong
- Department of Ophthalmology, Second Hospital of Jilin University, Changchun 130041, China
| | - Haile Liu
- Department of Ophthalmology, First Hospital of Jilin University, Changchun 130021, China, China
| | - Hua Ren
- Department of Ophthalmology, First Hospital of Jilin University, Changchun 130021, China, China.
| | - Zhihua Cui
- Department of Ophthalmology, First Hospital of Jilin University, Changchun 130021, China, China.
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Abstract
The sphingolipid family of lipids modulate several cellular processes, including proliferation, cell cycle regulation, inflammatory signaling pathways, and cell death. Several members of the sphingolipid pathway have opposing functions and thus imbalances in sphingolipid metabolism result in deregulated cellular processes, which cause or contribute to diseases and disorders in humans. A key cellular process regulated by sphingolipids is apoptosis, or programmed cell death. Sphingolipids play an important role in both extrinsic and intrinsic apoptotic pathways depending on the stimuli, cell type and cellular response to the stress. During mitochondrial-mediated apoptosis, multiple pathways converge on mitochondria and induce mitochondrial outer membrane permeabilization (MOMP). MOMP results in the release of intermembrane space proteins such as cytochrome c and Apaf1 into the cytosol where they activate the caspases and DNases that execute cell death. The precise molecular components of the pore(s) responsible for MOMP are unknown, but sphingolipids are thought to play a role. Here, we review evidence for a role of sphingolipids in the induction of mitochondrial-mediated apoptosis with a focus on potential underlying molecular mechanisms by which altered sphingolipid metabolism indirectly or directly induce MOMP. Data available on these mechanisms is reviewed, and the focus and limitations of previous and current studies are discussed to present important unanswered questions and potential future directions.
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Affiliation(s)
- Gauri A Patwardhan
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA
| | - Levi J Beverly
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA.,Department of Medicine, University of Louisville, Louisville, KY, 40202, USA.,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA
| | - Leah J Siskind
- Department of Pharmacology and Toxicology, University of Louisville, Louisville, KY, 40202, USA. .,James Graham Brown Cancer Center, University of Louisville, 505 South Hancock Street, Clinical and Translational Research Building, Room 203, Louisville, KY, 40202, USA.
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43
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Ji C, Huang JW, Xu QY, Zhang J, Lin MT, Tu Y, He L, Bi ZG, Cheng B. Gremlin inhibits UV-induced skin cell damages via activating VEGFR2-Nrf2 signaling. Oncotarget 2016; 7:84748-84757. [PMID: 27713170 PMCID: PMC5356696 DOI: 10.18632/oncotarget.12454] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Accepted: 09/23/2016] [Indexed: 12/14/2022] Open
Abstract
Ultra Violet (UV) radiation induces reactive oxygen species (ROS) production, DNA oxidation and single strand breaks (SSBs), which will eventually lead to skin cell damages or even skin cancer. Here, we tested the potential activity of gremlin, a novel vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) agonist, against UV-induced skin cell damages. We show that gremlin activated VEGFR2 and significantly inhibited UV-induced death and apoptosis of skin keratinocytes and fibroblasts. Pharmacological inhibition or shRNA-mediated knockdown of VEGFR2 almost abolished gremlin-mediated cytoprotection against UV in the skin cells. Further studies showed that gremlin activated VEGFR2 downstream NF-E2-related factor 2 (Nrf2) signaling, which appeared required for subsequent skin cell protection. Nrf2 shRNA knockdown or S40T dominant negative mutation largely inhibited gremlin-mediated skin cell protection against UV. At last, we show that gremlin dramatically inhibited UV-induced ROS production and DNA SSB formation in skin keratinocytes and fibroblasts. We conclude that gremlin protects skin cells from UV damages via activating VEGFR2-Nrf2 signaling. Gremlin could be further tested as a novel anti-UV skin protectant.
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Affiliation(s)
- Chao Ji
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
| | - Jin-wen Huang
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
| | - Qiu-yun Xu
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
| | - Jing Zhang
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
| | - Meng-ting Lin
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
| | - Ying Tu
- Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming 650032, Yunnan, China
| | - Li He
- Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming 650032, Yunnan, China
| | - Zhi-gang Bi
- Department of Dermatology, BenQ Medical Center, Nanjing Medical University, Nanjing 210019, Jiangsu, China
| | - Bo Cheng
- Department of Dermatology, The First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian, China
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Shaheen HM, Onoda A, Shinkai Y, Nakamura M, El-Ghoneimy AA, El-Sayed YS, Takeda K, Umezawa M. The ceramide inhibitor fumonisin B1 mitigates the pulmonary effects of low-dose diesel exhaust inhalation in mice. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2016; 132:390-396. [PMID: 27376354 DOI: 10.1016/j.ecoenv.2016.06.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 06/15/2016] [Accepted: 06/17/2016] [Indexed: 06/06/2023]
Abstract
Recent studies have suggested that inhalation of diesel exhaust (DE), a major source of air pollution, results in pulmonary alterations; however, the effects of DE at low concentrations are poorly understood. Therefore, this study was conducted to elucidate the pulmonary effects of low-level exposure to DE and the potential role of a ceramide de novo biosynthesis inhibitor, fumonisin B1 (FB1) to ameliorate the DE-toxicity. Male C57BL/6J mice underwent 1- or 7-day experiments (4 equal groups/experiment) and were assigned to the control, DE (0.1mg/m(3)), FB1 (6.75mg/kg body weight SC at days 0, 3 and 6) or DE+FB1 groups. DE and/or FB1 treatment had no effect on the expression of Nos2, a biomarker of oxidative stress. Ceramide production in the bronchial epithelial cells and Sphk1 mRNA expression were induced in the lung after the 7-day DE exposure and were partially suppressed by the FB1 treatment. Additionally, the effects of DE on SP-A and SP-D mRNA expression were also suppressed by the FB1 treatment. These results suggest that ceramide and Sphk1 may be sensitive biomarkers for low-level DE-induced pulmonary effects. Collectively, ceramide likely contributes to the DE-induced early stage of airway inflammation, which is considered a potential pulmonary target during low-level DE exposure.
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Affiliation(s)
- Hazem M Shaheen
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan; Department of Pharmacology, Faculty of Veterinary Medicine, Damanhour University, Egypt.
| | - Atsuto Onoda
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan; Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Japan; Research Fellow of Japan Society for the Promotion of Science, Japan.
| | - Yusuke Shinkai
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan.
| | - Masayuki Nakamura
- Department of Hygienic Chemistry, Graduate School of Pharmaceutical Sciences, Tokyo University of Science, Japan.
| | - Ashraf A El-Ghoneimy
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan; Department of Pharmacology, Faculty of Veterinary Medicine, South Valley University, Egypt.
| | - Yasser S El-Sayed
- Department of Veterinary Forensic Medicine and Toxicology, Faculty of Veterinary Medicine, Damanhour University, Egypt.
| | - Ken Takeda
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan.
| | - Masakazu Umezawa
- The Center for Environmental Health Science for the Next Generation, Research Institute for Science and Technology, Organization for Research Advancement, Tokyo University of Science, Japan.
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45
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Li DD, Zhong BW, Zhang HX, Zhou HY, Luo J, Liu Y, Xu GC, Luan CS, Fang J. Inhibition of the oxidative stress-induced miR-23a protects the human retinal pigment epithelium (RPE) cells from apoptosis through the upregulation of glutaminase and glutamine uptake. Mol Biol Rep 2016; 43:1079-87. [DOI: 10.1007/s11033-016-4041-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 07/08/2016] [Indexed: 11/28/2022]
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46
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3H-1,2-dithiole-3-thione protects retinal pigment epithelium cells against Ultra-violet radiation via activation of Akt-mTORC1-dependent Nrf2-HO-1 signaling. Sci Rep 2016; 6:25525. [PMID: 27151674 PMCID: PMC4858705 DOI: 10.1038/srep25525] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2015] [Accepted: 04/14/2016] [Indexed: 12/14/2022] Open
Abstract
Excessive UV radiation and reactive oxygen species (ROS) cause retinal pigment epithelium (RPE) cell injuries. Nrf2 regulates transcriptional activation of many anti-oxidant genes. Here, we tested the potential role of 3H-1,2-dithiole-3-thione (D3T) against UV or ROS damages in cultured RPE cells (both primary cells and ARPE-19 line). We showed that D3T significantly inhibited UV-/H2O2-induced RPE cell death and apoptosis. UV-stimulated ROS production was dramatically inhibited by D3T pretreatment. D3T induced Nrf2 phosphorylation in cultured RPE cells, causing Nrf2 disassociation with KEAP1 and its subsequent nuclear accumulation. This led to expression of antioxidant response elements (ARE)-dependent gene heme oxygenase-1 (HO-1). Nrf2-HO-1 activation was required for D3T-mediated cytoprotective effect. Nrf2 shRNA knockdown or S40T dominant negative mutation as well as the HO-1 inhibitor Zinc protoporphyrin (ZnPP) largely inhibited D3T’s RPE cytoprotective effects against UV radiation. Yet, exogenous overexpression Nrf2 enhanced D3T’s activity in RPE cells. Further studies showed that D3T activated Akt/mTORC1 in cultured RPE cells. Akt-mTORC1 inhibitors, or Akt1 knockdown by shRNA, not only inhibited D3T-induced Nrf2-HO-1 activation, but also abolished the RPE cytoprotective effects. In vivo, D3T intravitreal injection protected from light-induced retinal dysfunctions in mice. Thus, D3T protects RPE cells from UV-induced damages via activation of Akt-mTORC1-Nrf2-HO-1 signaling axis.
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Li F, Zheng X, Liu Y, Li P, Liu X, Ye F, Zhao T, Wu Q, Jin X, Li Q. Different Roles of CHOP and JNK in Mediating Radiation-Induced Autophagy and Apoptosis in Breast Cancer Cells. Radiat Res 2016; 185:539-48. [PMID: 27135967 DOI: 10.1667/rr14344.1] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Unfolded protein response (UPR) is comprised of complex and conserved stress pathways that function as a short-term adaptive mechanism to reduce levels of unfolded or misfolded proteins and maintain homeostasis in the endoplasmic reticulum (ER). UPR can be triggered by prolonged or persistent ER stress under many physiological or pathological conditions, including radiation exposure. Radiation-induced ER stress elicits autophagy and apoptosis in cancer cells, where C/EBP homologous protein (CHOP) and c-Jun NH2-terminal kinase (JNK) may play crucial roles. However, the specific mechanisms that regulate autophagy and apoptosis through CHOP and JNK after radiation exposure and how the balance of these activities determines the cellular radiosensitivity remain largely unclear. In this study, we found that exposure to X-ray radiation induced ER stress, UPR and high expression of CHOP and JNK. Furthermore, autophagy and apoptosis occurred in sequential order when breast cancer MDA-MB-231 and MCF-7 cells were exposed to X-ray radiation. CHOP gene knockdown with RNA interference inhibited autophagy and enhanced radiosensitivity in MDA-MB-231 cells, while impacting apoptosis and subsequently increasing radioresistance in MCF-7 cells. However, treatment with JNK inhibitor decreased autophagy while promoting apoptosis, thereby leading to radiosensitivity in both cell lines. Our results indicate that CHOP mediates radiation-induced autophagy and apoptosis in a cellular environment. Importantly, the functional consistency of regulating apoptosis and autophagy in these two irradiated breast cancer cell lines suggests that JNK may be more useful as a potential target for maximizing the efficacy of radiation therapy for breast cancers.
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Affiliation(s)
- Feifei Li
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and.,d University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xiaogang Zheng
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and.,d University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan Liu
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and.,d University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ping Li
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and
| | - Xiongxiong Liu
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and
| | - Fei Ye
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and.,d University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ting Zhao
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and
| | - Qingfeng Wu
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Xiaodong Jin
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and
| | - Qiang Li
- a Institute of Modern Physics, Chinese Academy of Sciences, Lanzhou 730000, China;,b Key Laboratory of Heavy Ion Radiation Biology and Medicine of Chinese Academy of Sciences, Lanzhou 730000, China;,c Key Laboratory of Basic Research on Heavy Ion Radiation Application in Medicine, Gansu Province, Lanzhou 730000, China; and
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Qin S. Blockade of MerTK Activation by AMPK Inhibits RPE Cell Phagocytosis. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2016; 854:773-8. [PMID: 26427488 DOI: 10.1007/978-3-319-17121-0_103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Timely removal of shed photoreceptor outer segments by retinal pigment epithelial cells (RPE) plays a key role in biological renewal of these highly peroxidizable structures and in maintenance of retina health. How environmental stress cause RPE cell dysfunction is undefined however. AMP-activated protein kinase (AMPK), a heterotrimer of a catalytic α subunit and regulatory β and γ subunits, maintains energy homeostasis by limiting energy utilization and/or promoting energy production when energy supply is compromised. Intriguingly, AMPK has been shown to be important in functions of RPE cells. In this mini-review, the role and mechanisms of AMPK in controlling RPE cell phagocytosis are discussed.
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Affiliation(s)
- Suofu Qin
- Retinal Disease Research, Department of Biological Sciences, Allergan, Inc., RD3-2D, 92612, Irvine, CA, USA.
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49
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Zhao M, Pan W, Shi RZ, Bai YP, You BY, Zhang K, Fu QM, Schuchman EH, He XX, Zhang GG. Acid Sphingomyelinase Mediates Oxidized-LDL Induced Apoptosis in Macrophage via Endoplasmic Reticulum Stress. J Atheroscler Thromb 2016; 23:1111-25. [PMID: 26923251 PMCID: PMC5090817 DOI: 10.5551/jat.32383] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Aim: Macrophage apoptosis is a vital event in advanced atherosclerosis, and oxidized low-density lipoprotein (ox-LDL) is a major contributor to this process. Acid sphingomyelinase (ASM) and ceramide are also involved in the induction of apoptosis, particularly in macrophages. Our current study focuses on ASM and investigates its role in ox-LDL-induced macrophage apoptosis. Methods: Human THP-1 and mouse peritoneal macrophages were cultured in vitro and treated with ox-LDL. ASM activity and ceramide levels were quantified using ultra performance liquid chromatography. Protein and mRNA levels were analyzed using Western blot analysis and quantitative realtime PCR, respectively. Cell apoptosis was determined using Hoechst staining and flow cytometry. Results: Ox-LDL-induced macrophage apoptosis was triggered by profound endoplasmic reticulum (ER) stress, leading to an upregulation of ASM activity and ceramide levels at an early stage. ASM was inhibited by siRNA or desipramine (DES), and/or ceramide was degraded by recombinant acid ceramidase (AC). These events attenuated the effect of ox-LDL on ER stress. In contrast, recombinant ASM upregulated ceramide and ER stress. ASM siRNA, DES, recombinant AC, and ER stress inhibitor 4-phenylbutyric acid were blocked by elevated levels of C/EBP homologous protein (CHOP); ox-LDL induced elevated levels of CHOP. These events attenuated macrophage apoptosis. Conclusion: These results indicate that ASM/ceramide signaling pathway is involved in ox-LDL-induced macrophage apoptosis via ER stress pathway.
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Affiliation(s)
- Min Zhao
- Departments of Nuclear Medicine, Xiangya Hospital, Central South University
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50
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Abstract
Studies over the past two decades have identified ceramide as a multifunctional central molecule in the sphingolipid biosynthetic pathway. Given its diverse tumor suppressive activities, molecular understanding of ceramide action will produce fundamental insights into processes that limit tumorigenesis and may identify key molecular targets for therapeutic intervention. Ceramide can be activated by a diverse array of stresses such as heat shock, genotoxic damage, oxidative stress and anticancer drugs. Ceramide triggers a variety of tumor suppressive and anti-proliferative cellular programs such as apoptosis, autophagy, senescence, and necroptosis by activating or repressing key effector molecules. Defects in ceramide generation and metabolism in cancer contribute to tumor cell survival and resistance to chemotherapy. The potent and versatile anticancer activity profile of ceramide has motivated drug development efforts to (re-)activate ceramide in established tumors. This review focuses on our current understanding of the tumor suppressive functions of ceramide and highlights the potential downstream targets of ceramide which are involved in its tumor suppressive action.
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