1
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Song P, Parsana D, Singh R, Pollock LM, Anand-Apte B, Perkins BD. Photoreceptor regeneration occurs normally in microglia-deficient irf8 mutant zebrafish following acute retinal damage. Sci Rep 2024; 14:20146. [PMID: 39209978 PMCID: PMC11362524 DOI: 10.1038/s41598-024-70859-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2024] [Accepted: 08/21/2024] [Indexed: 09/04/2024] Open
Abstract
Microglia are resident immune cells in the central nervous system, including the retina that surveil the environment for damage and infection. Following retinal damage, microglia undergo morphological changes, migrate to the site of damage, and express and secrete pro-inflammatory signals. In the zebrafish retina, inflammation induces the reprogramming and proliferation of Müller glia and the regeneration of neurons following damage or injury. Immunosuppression or pharmacological ablation of microglia reduce or abolish Müller glia proliferation. We evaluated the retinal architecture and retinal regeneration in adult zebrafish irf8 mutants, which have significantly depleted numbers of microglia. We show that irf8 mutants have normal retinal structure at 3 months post fertilization (mpf) and 6 mpf but fewer cone photoreceptors by 10 mpf. Surprisingly, light-induced photoreceptor ablation induced Müller glia proliferation in irf8 mutants and cone and rod photoreceptor regeneration. Light-damaged retinas from both wild-type and irf8 mutants show upregulated expression of mmp-9, il8, and tnfβ pro-inflammatory cytokines. Our data demonstrate that adult zebrafish irf8 mutants can regenerate normally following acute retinal injury. These findings suggest that microglia may not be essential for retinal regeneration in zebrafish and that other mechanisms can compensate for the reduction in microglia numbers.
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Affiliation(s)
- Ping Song
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Dhwani Parsana
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Rupesh Singh
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Lana M Pollock
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
| | - Bela Anand-Apte
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA
| | - Brian D Perkins
- Department of Ophthalmic Research, Cole Eye Institute, Cleveland Clinic, Cleveland, OH, USA.
- Department of Ophthalmology, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA.
- Department of Molecular Medicine, Cleveland Clinic Lerner College of Medicine, Case Western Reserve University, Cleveland, OH, USA.
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2
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Young AP, Szczesniak AM, Hsu K, Kelly ME, Denovan-Wright EM. Enantiomeric Agonists of the Type 2 Cannabinoid Receptor Reduce Retinal Damage during Proliferative Vitreoretinopathy and Inhibit Hyperactive Microglia In Vitro. ACS Pharmacol Transl Sci 2024; 7:1348-1363. [PMID: 38751621 PMCID: PMC11091991 DOI: 10.1021/acsptsci.4c00014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 04/09/2024] [Accepted: 04/16/2024] [Indexed: 05/18/2024]
Abstract
Microglia are resident immune cells of the central nervous system (CNS) and propagate inflammation following damage to the CNS, including the retina. Proliferative vitreoretinopathy (PVR) is a condition that can emerge following retinal detachment and is characterized by severe inflammation and microglial proliferation. The type 2 cannabinoid receptor (CB2) is an emerging pharmacological target to suppress microglial-mediated inflammation when the eyes or brain are damaged. CB2-knockout mice have exacerbated inflammation and retinal pathology during experimental PVR. We aimed to assess the anti-inflammatory effects of CB2 stimulation in the context of retinal damage and also explore the mechanistic roles of CB2 in microglia function. To target CB2, we used a highly selective agonist, HU-308, as well as its enantiomer, HU-433, which is a putative selective agonist. First, β-arrestin2 and Gαi recruitment was measured to compare activation of human CB2 in an in vitro heterologous expression system. Both agonists were then utilized in a mouse model of PVR, and the effects on retinal damage, inflammation, and cell death were assessed. Finally, we used an in vitro model of microglia to determine the effects of HU-308 and HU-433 on phagocytosis, cytokine release, migration, and intracellular signaling. We observed that HU-308 more strongly recruited both β-arrestin2 and Gαi compared to HU-433. Stimulation of CB2 with either drug effectively blunted LPS- and IFNγ-mediated signaling as well as NO and TNF release from microglia. Furthermore, both drugs reduced IL-6 accumulation, total caspase-3 cleavage, and retinal pathology following the induction of PVR. Ultimately, this work supports that CB2 is a valuable target for drugs to suppress inflammation and cell death associated with infection or sterile retinopathy, although the magnitude of effector recruitment may not be predictive of anti-inflammatory capacity.
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Affiliation(s)
- Alexander P. Young
- Department
of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Anna-Maria Szczesniak
- Department
of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Karolynn Hsu
- Department
of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
| | - Melanie E.M. Kelly
- Department
of Pharmacology, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Department
of Ophthalmology & Visual Sciences, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
- Department
of Anesthesia, Pain Management & Perioperative Medicine, Dalhousie University, Halifax, Nova Scotia B3H 4R2, Canada
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3
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Velazquez-Soto H, Groman-Lupa S, Cruz-Aguilar M, Salazar AL, Zenteno JC, Jimenez-Martinez MC. Exogenous CFH Modulates Levels of Pro-Inflammatory Mediators to Prevent Oxidative Damage of Retinal Pigment Epithelial Cells with the At-Risk CFH Y402H Variant. Antioxidants (Basel) 2023; 12:1540. [PMID: 37627535 PMCID: PMC10451625 DOI: 10.3390/antiox12081540] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Revised: 07/13/2023] [Accepted: 07/24/2023] [Indexed: 08/27/2023] Open
Abstract
Age-related macular degeneration (AMD) is a complex, progressive degenerative retinal disease. Retinal pigment epithelial (RPE) cells play an important role in the immune defense of the eye and their dysfunction leads to the progressive irreversible degeneration of photoreceptors. Genetic factors, chronic inflammation, and oxidative stress have been implicated in AMD pathogenesis. Oxidative stress causes RPE injury, resulting in a chronic inflammatory response and cell death. The Y402H polymorphism in the complement factor H (CFH) protein is an important risk factor for AMD. However, the functional significance of CFH Y402H polymorphism remains unclear. In the present study, we investigated the role of CFH in the pro-inflammatory response using an in vitro model of oxidative stress in the RPE with the at-risk CFH Y402H variant. ARPE-19 cells with the at-risk CFH Y402H variant were highly susceptible to damage caused by oxidative stress, with increased levels of inflammatory mediators and pro-apoptotic factors that lead to cell death. Pretreatment of the ARPE-19 cell cultures with exogenous CFH prior to the induction of oxidative stress prevented damage and cell death. This protective effect may be related to the negative regulation of pro-inflammatory cytokines. CFH contributes to cell homeostasis and is required to modulate the pro-inflammatory cytokine response under oxidative stress in the ARPE-19 cells with the at-risk CFH Y402H variant.
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Affiliation(s)
- Henry Velazquez-Soto
- Department of Immunology, Research Unit, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico; (H.V.-S.)
| | - Sergio Groman-Lupa
- Department of Immunology, Research Unit, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico; (H.V.-S.)
| | - Marisa Cruz-Aguilar
- Department of Immunology, Research Unit, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico; (H.V.-S.)
| | - Alberto L. Salazar
- Department of Immunology, Research Unit, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico; (H.V.-S.)
| | - Juan C. Zenteno
- Department of Genetics, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico
- Department of Biochemistry, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico
| | - Maria C. Jimenez-Martinez
- Department of Immunology, Research Unit, Institute of Ophthalmology “Conde de Valenciana Foundation”, Mexico City 06800, Mexico; (H.V.-S.)
- Department of Biochemistry, Faculty of Medicine, National Autonomous University of Mexico, Mexico City 04510, Mexico
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4
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Tugizov SM. Molecular Pathogenesis of Human Immunodeficiency Virus-Associated Disease of Oropharyngeal Mucosal Epithelium. Biomedicines 2023; 11:1444. [PMID: 37239115 PMCID: PMC10216750 DOI: 10.3390/biomedicines11051444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 05/01/2023] [Accepted: 05/11/2023] [Indexed: 05/28/2023] Open
Abstract
The oropharyngeal mucosal epithelia have a polarized organization, which is critical for maintaining a highly efficient barrier as well as innate immune functions. In human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) disease, the barrier and innate immune functions of the oral mucosa are impaired via a number of mechanisms. The goal of this review was to discuss the molecular mechanisms of HIV/AIDS-associated changes in the oropharyngeal mucosa and their role in promoting HIV transmission and disease pathogenesis, notably the development of opportunistic infections, including human cytomegalovirus, herpes simplex virus, and Epstein-Barr virus. In addition, the significance of adult and newborn/infant oral mucosa in HIV resistance and transmission was analyzed. HIV/AIDS-associated changes in the oropharyngeal mucosal epithelium and their role in promoting human papillomavirus-positive and negative neoplastic malignancy are also discussed.
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Affiliation(s)
- Sharof M Tugizov
- Department of Medicine, School of Medicine, University of California, San Francisco, CA 94143, USA
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5
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Bernardo-Colón A, Lerner M, Becerra SP. Pigment epithelium-derived factor is an interleukin-6 antagonist in the RPE: Insight of structure-function relationships. Front Physiol 2022; 13:1045613. [PMID: 36467689 PMCID: PMC9709256 DOI: 10.3389/fphys.2022.1045613] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Accepted: 11/03/2022] [Indexed: 07/04/2024] Open
Abstract
Retinal and choroidal inflammatory lesions increase the levels of the pro-inflammatory cytokine interleukin-6 (IL-6). Pigment epithelium-derived factor (PEDF) has anti-inflammatory properties, but it is not known if it can prevent the production of IL-6 by the retinal pigment epithelium. To investigate the anti-inflammatory effects of PEDF in the RPE, we used human ARPE-19 cells stimulated with human recombinant tumor necrosis factor-alpha (TNF-α) to induce overexpression of the IL6 gene. We found that the viability of ARPE-19 cells decreased by 22% with TNF-α at 10 ng/ml, being drastically decreased at ≥50 ng/ml. TNF-α at 5-100 ng/ml elevated the production and secretion of IL-6 protein, as measured by ELISA. To challenge the TNF-α-mediated stimulation of IL-6, we used recombinant human PEDF protein. PEDF at 100 nM recovered the TNF-α-mediated loss of cell viability and repressed IL-6 gene expression as determined by RT-PCR. PEDF at 10-100 nM attenuated the IL-6 protein secretion in a dose dependent fashion (IC50 = 65 nM), being abolished with 100 nM PEDF. To map the region that confers the IL-6 blocking effect to the PEDF polypeptide, we used chemically synthesized peptides designed from its biologically active domains, pro-death 34-mer, and pro-survival 44-mer and 17-mer (H105A), to challenge the IL-6 overproduction. The pro-survival peptides recovered the TNF-α-mediated cell viability loss, and inhibited IL-6 secretion, while the 34-mer did not have an effect, suggesting a role for the pro-survival domain in blocking TNF-α-mediated cell death and IL-6 stimulation. Our findings position PEDF as a novel antagonistic agent of IL-6 production in RPE cells, underscoring its use for the management of retinal disease-related inflammation.
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Affiliation(s)
| | | | - S. Patricia Becerra
- Laboratory of Retinal Cell and Molecular Biology, Section of Protein Structure and Function, National Eye Institute, National Institutes of Health, Bethesda, MD, United States
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6
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Wu J, Hu J, Zhang F, Jin Q, Sun X. High glucose promotes IL-17A-induced gene expression through histone acetylation in retinal pigment epithelium cells. Int Immunopharmacol 2022; 110:108893. [DOI: 10.1016/j.intimp.2022.108893] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2022] [Revised: 05/13/2022] [Accepted: 05/23/2022] [Indexed: 11/05/2022]
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7
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Looking into the Eyes—In Vitro Models for Ocular Research. Int J Mol Sci 2022; 23:ijms23169158. [PMID: 36012421 PMCID: PMC9409455 DOI: 10.3390/ijms23169158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 08/10/2022] [Accepted: 08/11/2022] [Indexed: 11/16/2022] Open
Abstract
Animal research undoubtedly provides scientists with virtually unlimited data but inflicts pain and suffering on animals. Currently, legislators and scientists alike are promoting alternative in vitro approaches allowing for an accurate evaluation of processes occurring in the body without animal sacrifice. Historically, one of the most infamous animal tests is the Draize test, mainly performed on rabbits. Even though this test was considered the gold standard for around 50 years, the Draize test fails to mimic human response mainly due to human and rabbit eye physiological differences. Therefore, many alternative assays were developed to evaluate ocular toxicity and drug effectiveness accurately. Here we review recent achievements in tissue engineering of in vitro 2D, 2.5D, 3D, organoid and organ-on-chip ocular models, as well as in vivo and ex vivo models in terms of their advantages and limitations.
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8
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Daldal H, Nazıroğlu M. Rituximab Attenuated Lipopolysaccharide-Induced Oxidative Cytotoxicity, Apoptosis, and Inflammation in the Human Retina Cells via Modulating the TRPM2 Signaling Pathways. Ocul Immunol Inflamm 2022; 30:1315-1328. [PMID: 35587813 DOI: 10.1080/09273948.2022.2075400] [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: 03/07/2022] [Revised: 04/17/2022] [Accepted: 05/04/2022] [Indexed: 10/18/2022]
Abstract
PURPOSE We investigated the possible protective effects of rituximab (RTX) on LPS-induced oxidant, inflammatory, and apoptotic adverse actions via the inhibition of TRPM2 channel in the adult retinal pigment epithelial-19 (ARPE-19) cells. METHODS In the cultured ARPE-19 cells, we induced five main groups as control, RTX (10 μg/ml), LPS (1 μg/ml), LPS+RTX, and LPS+TRPM2 blockers (ACA or 2/APB). RESULTS The levels of apoptosis, cell death, mitochondrial free reactive oxygen radicals (mitROS), cytosolic ROS, lipid peroxidation, caspase -3, caspase -8, caspase -9, ADP-ribose-induced TRPM2 current density, TNF-α, IL-1β, cytosolic free Zn2+, and Ca2+ were increased by LPS, although their levels were diminished by the treatments of RTX and TRPM2 blockers. CONCLUSIONS The LPS-induced mitROS, inflammatory cytokine, and apoptosis levels were modulated via TRPM2 inhibition in the human retinal epithelial cells by the RTX treatment. The RTX may be considered as a new therapeutic approach to LPS-induced human retinal epithelial cell injury.
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Affiliation(s)
- Hatice Daldal
- Department of Ophthalmology, Faculty of Medicine, Usak University, Usak, Turkey
| | - Mustafa Nazıroğlu
- Neuroscience Research Center, Suleyman Demirel University, Isparta, Turkey
- Drug Discovery Unit, BSN Health, Analyses, Innov., Consult., Org., Agricul., Ltd, Isparta, Turkey
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9
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Fangary S, Abdel-Halim M, Fathalla RK, Hassan R, Farag N, Engel M, Mansour S, Tammam SN. Nanoparticle Fraught Liposomes: A Platform for Increased Antibiotic Selectivity in Multidrug Resistant Bacteria. Mol Pharm 2022; 19:3163-3177. [PMID: 35876358 DOI: 10.1021/acs.molpharmaceut.2c00258] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Increasing antibiotic concentrations within bacterial cells while reducing them in mammalian ones would ultimately result in an enhancement of antibacterial actions, overcoming multidrug resistance, all while minimizing toxicity. Nanoparticles (NPs) have been used in numerous occasions to overcome antibiotic resistance, poor drug solubility, and stability. However, the concomitant increase in antibiotic concentration in mammalian cells and the resultant toxicity are usually overlooked. Without compromising bacterial cell fusion, large liposomes (Lip) have been reported to show reduced uptake in mammalian cells. Therefore, in this work, small NP fraught liposomes (NP-Lip) were formulated with the aim of increasing NP uptake and antibiotic delivery in bacterial cells but not in mammalian ones. Small polylactic-co-glycolic acid NPs were therefore loaded with erythromycin (Er), an antibiotic with low membrane permeability that is susceptible to drug efflux, and 3c, a 5-cyanothiazolyl urea derivative with low solubility and stability. In vitro experiments demonstrated that the incorporation of small NPs into large Lip resulted in a reduction in NP uptake by HEK293 cells while increasing it in Gram-negative bacteria (Escherichia coli DH5α, E. coli K12, and Pseudomonas aeruginosa), consequently resulting in an enhancement of antibiotic selectivity by fourfold toward E. coli (both strains) and eightfold toward P. aeruginosa. Ocular administration of NP-Lip in a P. aeruginosa keratitis mouse model demonstrated the ability of Er/3c-loaded NP-Lip to result in a complete recovery. More importantly, in comparison to NPs, the ocular administration of NP-Lip showed a reduction in TNF-alpha and IL-6 levels, implying reduced interaction with mammalian cells in vivo. This work therefore clearly demonstrated how tailoring the nano-bio interaction could result in selective drug delivery and a reduction in toxicity.
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Affiliation(s)
- Suzan Fangary
- Department of Pharmaceutical Technology, German University in Cairo (GUC), New Cairo 11835, Egypt
| | - Mohammad Abdel-Halim
- Department of Pharmaceutical Chemistry, German University in Cairo (GUC), New Cairo 24681, Egypt
| | - Reem K Fathalla
- Pharmaceutical and Medicinal Chemistry, Saarland University, D-66123 Saarbrücken, Germany
| | - Raghda Hassan
- Department of Pharmaceutical Technology, German University in Cairo (GUC), New Cairo 11835, Egypt
| | - Noha Farag
- Department of Microbiology and Immunology, German University in Cairo (GUC), New Cairo 11835, Egypt
| | - Matthias Engel
- Pharmaceutical and Medicinal Chemistry, Saarland University, D-66123 Saarbrücken, Germany
| | - Samar Mansour
- Department of Pharmaceutical Technology, German University in Cairo (GUC), New Cairo 11835, Egypt.,Department of Pharmaceutics and Industrial Pharmacy-Faculty of Pharmacy, Ain Shams University, Cairo 11566, Egypt
| | - Salma N Tammam
- Department of Pharmaceutical Technology, German University in Cairo (GUC), New Cairo 11835, Egypt
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10
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Collagen Mimetic Peptides Promote Adherence and Migration of ARPE-19 Cells While Reducing Inflammatory and Oxidative Stress. Int J Mol Sci 2022; 23:ijms23137004. [PMID: 35806007 PMCID: PMC9266392 DOI: 10.3390/ijms23137004] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2022] [Revised: 06/17/2022] [Accepted: 06/20/2022] [Indexed: 11/28/2022] Open
Abstract
Epithelial cells of multiple types produce and interact with the extracellular matrix to maintain structural integrity and promote healthy function within diverse endogenous tissues. Collagen is a critical component of the matrix, and challenges to collagen’s stability in aging, disease, and injury influence survival of adherent epithelial cells. The retinal pigment epithelium (RPE) is important for maintaining proper function of the light-sensitive photoreceptors in the neural retina, in part through synergy with the collagen-rich Bruch’s membrane that promotes RPE adherence. Degradation of Bruch’s is associated with RPE degeneration, which is implicated early in age-related macular degeneration, a leading cause of irreversible vision loss worldwide. Collagen mimetic peptides (CMPs) effectively repair damage to collagen helices, which are present in all collagens. Our previous work indicates that in doing so, CMPs promote survival and integrity of affected cells and tissues in models of ocular injury and disease, including wounding of corneal epithelial cells. Here, we show that CMPs increase adherence and migration of the ARPE-19 line of human RPE cells challenged by digestion of their collagen substrate. Application of CMPs also reduced both ARPE-19 secretion of pro-inflammatory cytokines (interleukins 6 and 8) and production of reactive oxygen species. Taken together, these results suggest that repairing collagen damaged by aging or other pathogenic processes in the posterior eye could improve RPE adherence and survival and, in doing so, reduce the inflammatory and oxidative stress that perpetuates the cycle of destruction at the root of age-related diseases of the outer retina.
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11
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Conti F, Lazzara F, Romano GL, Platania CBM, Drago F, Bucolo C. Caffeine Protects Against Retinal Inflammation. Front Pharmacol 2022; 12:824885. [PMID: 35069225 PMCID: PMC8773454 DOI: 10.3389/fphar.2021.824885] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Accepted: 12/13/2021] [Indexed: 01/28/2023] Open
Abstract
Caffeine, one of the most consumed central nervous system (CNS) stimulants, is an antagonist of A1 and A2A adenosine receptors. In this study, we investigated the potential protective effects of this methylxanthine in the retinal tissue. We tested caffeine by using in vitro and in vivo paradigms of retinal inflammation. Human retinal pigment epithelial cells (ARPE-19) were exposed to lipopolysaccharide (LPS) with or without caffeine. This latter was able to reduce the inflammatory response in ARPE-19 cells exposed to LPS, attenuating the release of IL-1β, IL-6, and TNF-α and the nuclear translocation of p-NFκB. Additionally, caffeine treatment restored the integrity of the ARPE-19 monolayer assessed by transepithelial electrical resistance (TEER) and the sodium fluorescein permeability test. Finally, the ischemia reperfusion (I/R) injury model was used in C57BL/6J mice to induce retinal inflammation and investigate the effects of caffeine treatment. Mouse eyes were treated topically with caffeine, and a pattern electroretinogram (PERG) was used to assess the retinal ganglion cell (RGC) function; furthermore, we evaluated the levels of IL-6 and BDNF in the retina. Retinal BDNF dropped significantly (p < 0.05) in the I/R group compared to the control group (normal mice); on the contrary, caffeine treatment maintained physiological levels of BDNF in the retina of I/R eyes. Caffeine was also able to reduce IL-6 mRNA levels in the retina of I/R eyes. In conclusion, these findings suggest that caffeine is a good candidate to counteract inflammation in retinal diseases.
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Affiliation(s)
- Federica Conti
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy
| | - Francesca Lazzara
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy
| | - Giovanni Luca Romano
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy.,Center for Research in Ocular Pharmacology-CERFO, University of Catania, Catania, Italy
| | - Chiara Bianca Maria Platania
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy
| | - Filippo Drago
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy.,Center for Research in Ocular Pharmacology-CERFO, University of Catania, Catania, Italy
| | - Claudio Bucolo
- Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Catania, Italy.,Center for Research in Ocular Pharmacology-CERFO, University of Catania, Catania, Italy
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12
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Saada J, McAuley RJ, Marcatti M, Tang TZ, Motamedi M, Szczesny B. Oxidative stress induces Z-DNA-binding protein 1-dependent activation of microglia via mtDNA released from retinal pigment epithelial cells. J Biol Chem 2022; 298:101523. [PMID: 34953858 PMCID: PMC8753185 DOI: 10.1016/j.jbc.2021.101523] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2021] [Revised: 12/17/2021] [Accepted: 12/19/2021] [Indexed: 11/28/2022] Open
Abstract
Oxidative stress, inflammation, and aberrant activation of microglia in the retina are commonly observed in ocular pathologies. In glaucoma or age-related macular degeneration, the chronic activation of microglia affects retinal ganglion cells and photoreceptors, respectively, contributing to gradual vision loss. However, the molecular mechanisms that cause activation of microglia in the retina are not fully understood. Here we show that exposure of retinal pigment epithelial (RPE) cells to chronic low-level oxidative stress induces mitochondrial DNA (mtDNA)-specific damage, and the subsequent translocation of damaged mtDNA to the cytoplasm results in the binding and activation of intracellular DNA receptor Z-DNA-binding protein 1 (ZBP1). Activation of the mtDNA/ZBP1 pathway triggers the expression of proinflammatory markers in RPE cells. In addition, we show that the enhanced release of extracellular vesicles (EVs) containing fragments of mtDNA derived from the apical site of RPE cells induces a proinflammatory phenotype of microglia via activation of ZBP1 signaling. Collectively, our report establishes oxidatively damaged mtDNA as an important signaling molecule with ZBP1 as its intracellular receptor in the development of an inflammatory response in the retina. We propose that this novel mtDNA-mediated autocrine and paracrine mechanism for triggering and maintaining inflammation in the retina may play an important role in ocular pathologies. Therefore, the molecular mechanisms identified in this report are potentially suitable therapeutic targets to ameliorate development of ocular pathologies.
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Affiliation(s)
- Jamal Saada
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, Texas, USA; Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Ryan J McAuley
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, Texas, USA
| | - Michela Marcatti
- Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, USA; Department of Neurology, University of Texas Medical Branch, Galveston, Texas, USA
| | - Tony Zifeng Tang
- Department of Neuroscience, Cell Biology and Anatomy, University of Texas Medical Branch, Galveston, Texas, USA
| | - Massoud Motamedi
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, Texas, USA
| | - Bartosz Szczesny
- Department of Ophthalmology and Visual Sciences, University of Texas Medical Branch, Galveston, Texas, USA; Department of Anesthesiology, University of Texas Medical Branch, Galveston, Texas, USA.
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13
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Salminen AT, Tithof J, Izhiman Y, Masters EA, McCloskey MC, Gaborski TR, Kelley DH, Pietropaoli AP, Waugh RE, McGrath JL. Endothelial cell apicobasal polarity coordinates distinct responses to luminally versus abluminally delivered TNF-α in a microvascular mimetic. Integr Biol (Camb) 2021; 12:275-289. [PMID: 33164044 DOI: 10.1093/intbio/zyaa022] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/28/2020] [Accepted: 10/05/2020] [Indexed: 12/27/2022]
Abstract
Endothelial cells (ECs) are an active component of the immune system and interact directly with inflammatory cytokines. While ECs are known to be polarized cells, the potential role of apicobasal polarity in response to inflammatory mediators has been scarcely studied. Acute inflammation is vital in maintaining healthy tissue in response to infection; however, chronic inflammation can lead to the production of systemic inflammatory cytokines and deregulated leukocyte trafficking, even in the absence of a local infection. Elevated levels of cytokines in circulation underlie the pathogenesis of sepsis, the leading cause of intensive care death. Because ECs constitute a key barrier between circulation (luminal interface) and tissue (abluminal interface), we hypothesize that ECs respond differentially to inflammatory challenge originating in the tissue versus circulation as in local and systemic inflammation, respectively. To begin this investigation, we stimulated ECs abluminally and luminally with the inflammatory cytokine tumor necrosis factor alpha (TNF-α) to mimic a key feature of local and systemic inflammation, respectively, in a microvascular mimetic (μSiM-MVM). Polarized IL-8 secretion and polymorphonuclear neutrophil (PMN) transmigration were quantified to characterize the EC response to luminal versus abluminal TNF-α. We observed that ECs uniformly secrete IL-8 in response to abluminal TNF-α and is followed by PMN transmigration. The response to abluminal treatment was coupled with the formation of ICAM-1-rich membrane ruffles on the apical surface of ECs. In contrast, luminally stimulated ECs secreted five times more IL-8 into the luminal compartment than the abluminal compartment and sequestered PMNs on the apical EC surface. Our results identify clear differences in the response of ECs to TNF-α originating from the abluminal versus luminal side of a monolayer for the first time and may provide novel insight into future inflammatory disease intervention strategies.
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Affiliation(s)
- Alec T Salminen
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Jeffrey Tithof
- Department of Mechanical Engineering, University of Rochester, Rochester, NY, USA
| | - Yara Izhiman
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Elysia A Masters
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Molly C McCloskey
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - Thomas R Gaborski
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
- Department of Biomedical Engineering, Rochester Institute of Technology, Rochester, NY, USA
| | - Douglas H Kelley
- Department of Mechanical Engineering, University of Rochester, Rochester, NY, USA
| | - Anthony P Pietropaoli
- Medicine, Pulmonary Disease and Critical Care, University of Rochester Medical Center, Rochester, NY, USA
| | - Richard E Waugh
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
| | - James L McGrath
- Department of Biomedical Engineering, University of Rochester, Rochester, NY, USA
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14
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Diacerein Inhibits Myopia Progression through Lowering Inflammation in Retinal Pigment Epithelial Cell. Mediators Inflamm 2021; 2021:6660640. [PMID: 34285659 PMCID: PMC8275387 DOI: 10.1155/2021/6660640] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 04/22/2021] [Accepted: 05/31/2021] [Indexed: 11/18/2022] Open
Abstract
Myopia is a highly prevalent refractive disorder. We investigated the effect of diacerein on monocular form deprivation (MFD) in hamsters as a possible therapeutic intervention. Diacerein is an anthraquinone derivative drug whose active metabolite is rhein. Diacerein or atropine was applied to the MFD hamsters, and their refractive error and axial length were measured after 21 days. The refractive error (control: −0.91 ± 0.023, atropine: −0.3 ± 0.08, and diacerein: −0.27 ± 0.07 D) and axial length (control: 0.401 ± 0.017, atropine: 0.326 ± 0.017, and diacerein: 0.334 ± 0.016 mm) showed statistically significant differences between control, atropine-treated, and diacerein-treated MFD eyes. Furthermore, we determined the level of transforming growth factor-beta- (TGF-) β1, matrix metalloproteinase- (MMP-) 2, type I collagen, interleukin- (IL-) 6, IL-8, and monocyte chemoattractant protein- (MCP-) 1 in the retina. Atropine and diacerein suppressed levels of the myopia-related TGF-β1 and MMP-2 while increasing type I collagen expression. They also inhibited the interleukin IL-6, IL-8, and MCP-1 levels. Diacerein reduced the IL-6, IL-8, and MCP-1 expression in ARPE-19 cells. Furthermore, diacerein inhibited inflammation by attenuating the phosphorylation of protein kinase B (AKT) and nuclear factor kappa-light-chain-enhancer of activated B (NF-κB) pathway. This suggests that diacerein has a therapeutic effect on myopia and is a potential treatment option.
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15
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Kim J, Park JY, Kong JS, Lee H, Won JY, Cho DW. Development of 3D Printed Bruch's Membrane-Mimetic Substance for the Maturation of Retinal Pigment Epithelial Cells. Int J Mol Sci 2021; 22:ijms22031095. [PMID: 33499245 PMCID: PMC7865340 DOI: 10.3390/ijms22031095] [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: 11/30/2020] [Revised: 01/20/2021] [Accepted: 01/21/2021] [Indexed: 12/15/2022] Open
Abstract
Retinal pigment epithelium (RPE) is a monolayer of the pigmented cells that lies on the thin extracellular matrix called Bruch's membrane. This monolayer is the main component of the outer blood-retinal barrier (BRB), which plays a multifunctional role. Due to their crucial roles, the damage of this epithelium causes a wide range of diseases related to retinal degeneration including age-related macular degeneration, retinitis pigmentosa, and Stargardt disease. Unfortunately, there is presently no cure for these diseases. Clinically implantable RPE for humans is under development, and there is no practical examination platform for drug development. Here, we developed porcine Bruch's membrane-derived bioink (BM-ECM). Compared to conventional laminin, the RPE cells on BM-ECM showed enhanced functionality of RPE. Furthermore, we developed the Bruch's membrane-mimetic substrate (BMS) via the integration of BM-ECM and 3D printing technology, which revealed structure and extracellular matrix components similar to those of natural Bruch's membrane. The developed BMS facilitated the appropriate functions of RPE, including barrier and clearance functions, the secretion of anti-angiogenic growth factors, and enzyme formation for phototransduction. Moreover, it could be used as a basement frame for RPE transplantation. We established BMS using 3D printing technology to grow RPE cells with functions that could be used for an in vitro model and RPE transplantation.
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Affiliation(s)
- Jongmin Kim
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (J.K.); (J.Y.P.); (H.L.)
| | - Ju Young Park
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (J.K.); (J.Y.P.); (H.L.)
| | - Jeong Sik Kong
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea;
| | - Hyungseok Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (J.K.); (J.Y.P.); (H.L.)
- Department of Mechanical and Biomedical Engineering, Kangwon National University, Chuncheon 24341, Korea
| | - Jae Yon Won
- Department of Ophthalmology and Visual Science, Eunpyeong St. Mary’s Hospital, The Catholic University of Korea, Seoul 03312, Korea
- Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul 14662, Korea
- Correspondence: (J.Y.W.); (D.W.C.)
| | - Dong Woo Cho
- Department of Mechanical Engineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea; (J.K.); (J.Y.P.); (H.L.)
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology (POSTECH), Pohang 37673, Korea;
- Institute of Convergence Science, Yonsei University, Seoul 03722, Korea
- Correspondence: (J.Y.W.); (D.W.C.)
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16
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Terheyden L, Roider J, Klettner A. Basolateral activation with TLR agonists induces polarized cytokine release and reduces barrier function in RPE in vitro. Graefes Arch Clin Exp Ophthalmol 2021; 259:413-424. [PMID: 32949301 PMCID: PMC7843481 DOI: 10.1007/s00417-020-04930-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Revised: 08/24/2020] [Accepted: 09/10/2020] [Indexed: 01/18/2023] Open
Abstract
PURPOSE Systemic inflammation may be of importance in the development of AMD. RPE cells can recognize danger signals with toll-like receptors (TLR) and may react in a pro-inflammatory manner. In this study, we evaluated the basal and apical secretions of TNFα, IL-6, and IL-1β in primary RPE cells and RPE/choroid explant cells under basolateral stimulation of TLR2, 3, and 4; the effects on barrier function; and their influence on neuronal cell viability. METHODS RPE/choroid tissue explants were prepared from porcine eyes and cultivated in modified Ussing chambers; primary porcine RPE cells on transwell plates. Cells were basally stimulated with agonists Pam2CSK4 (Pam; TLR2), polyinosinic/polycytidylic acid (Poly I:C; TLR3), and lipopolysaccharide (LPS; TLR4) for 24 h. Supernatants were evaluated with ELISA for cytokines TNFα, IL-6, and IL-1β. Apical supernatants were applied to SHSY-5Y cells, and cell viability was evaluated in MTT assay. Barrier function was tested by measuring transepithelial electrical resistance (TER) and occludin immunostaining. RESULTS None of the tested TLR agonists was toxic on RPE cells after 24 h of exposure. Unstimulated RPE cells secreted hardly any cytokines. Pam induced IL-6, IL-1ß, and TNFα on the basal and apical sides at all concentrations tested. Poly I:C induced IL-6 and TNFα primarily at the basal side at lower but on both sides at higher concentrations. LPS induced IL-6, IL-1ß, and TNFα apically and basally at all concentrations tested. In the RPE/choroid, a strong difference between apical and basal secretions could be found. IL-6 was constitutively secreted basally, but not apically, but was induced by all agonists on both sides. IL-1ß and TNFα alpha were strongly induced on the basal side by all agonists. TER was reduced by all agonists, with Pam and LPS being effective in all concentrations tested. Occludin expression was unaltered, but the distribution was influenced by the agonists, with a less distinct localization at the cell borders after treatment. None of the agonists or supernatants of treated RPE and RPE/choroid organ cultures exerted any effect on viability of SHSY-5Y cells. CONCLUSIONS Danger signals activating TLRs can induce polarized cytokine expression and contribute to the loss of barrier function in the RPE.
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Affiliation(s)
- Laura Terheyden
- grid.9764.c0000 0001 2153 9986University Medical Center, Department of Ophthalmology, University of Kiel, Arnold-Heller-Str. 3, Haus B2, 24105 Kiel, Germany
| | - Johann Roider
- grid.9764.c0000 0001 2153 9986University Medical Center, Department of Ophthalmology, University of Kiel, Arnold-Heller-Str. 3, Haus B2, 24105 Kiel, Germany
| | - Alexa Klettner
- grid.9764.c0000 0001 2153 9986University Medical Center, Department of Ophthalmology, University of Kiel, Arnold-Heller-Str. 3, Haus B2, 24105 Kiel, Germany
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17
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Lee BJ, Byeon HE, Cho CS, Kim YH, Kim JH, Che JH, Seok SH, Kwon JW, Kim JH, Lee K. Histamine causes an imbalance between pro-angiogenic and anti-angiogenic factors in the retinal pigment epithelium of diabetic retina via H4 receptor/p38 MAPK axis. BMJ Open Diabetes Res Care 2020; 8:8/2/e001710. [PMID: 33328159 PMCID: PMC7745681 DOI: 10.1136/bmjdrc-2020-001710] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/21/2020] [Accepted: 10/29/2020] [Indexed: 12/30/2022] Open
Abstract
INTRODUCTION Systemic histaminergic activity is elevated in patients with diabetes mellitus. There are a few studies suggesting that histamine is implicated in the pathogenesis of diabetes, but the exact role of histamine in the development of diabetic retinopathy is unclear. The aim of this study was to investigate the role of histamine receptor H4 (HRH4) in the regulation of retinal pigment epithelium (RPE)-derived pro-angiogenic and anti-angiogenic factors under diabetic conditions. RESEARCH DESIGN AND METHODS The levels of vascular endothelial growth factor (VEGF), interleukin-6 (IL-6), histamine and histidine decarboxylase (HDC) in the serum and vitreous samples of patients with diabetes were compared with those of patients without diabetes. The effect of hyperglycemia on expression levels of HRH4, VEGF, IL-6 and pigment epithelium-derived factor (PEDF) in the RPE was determined. The role of HRH4 in high glucose-induced regulation of VEGF, IL-6 and PEDF in ARPE-19 cells and the underlying regulatory mechanism were verified using an RNA interference-mediated knockdown study. RESULTS The serum and vitreous levels of VEGF, IL-6, histamine and HDC were more increased in patients with diabetic retinopathy than in patients without diabetes. HRH4 was overexpressed in RPE both in vitro and in vivo. Histamine treatment upregulated VEGF and IL-6 and downregulated PEDF expression in ARPE-19 cells cultivated under hyperglycemic conditions. Hyperglycemia-induced phosphorylation of p38 and subsequent upregulation of VEGF and IL-6 and downregulation of PEDF were dampened by small interfering RNA-mediated knockdown of HRH4 in ARPE-19 cells. CONCLUSIONS Taken together, HRH4 was a critical regulator of VEGF, IL-6 and PEDF in the RPE under hyperglycemic conditions and the p38 mitogen-activated protein kinase pathway mediated this regulatory mechanism.
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Affiliation(s)
- Byung Joo Lee
- Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Republic of Korea
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University, Seoul, Republic of Korea
| | - Hye Eun Byeon
- Institute of Medical Science, Ajou University School of Medicine and Graduate School of Medicine, Suwon, Gyeonggi-do, Republic of Korea
| | - Chang Sik Cho
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
| | - Young Ho Kim
- Department of Ophthalmology, Korea University College of Medicine, Seoul, Republic of Korea
| | | | - Jeong-Hwan Che
- Biomedical Center for Animal Resource Development and Institute for Experimental Animals, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Seung Hyeok Seok
- Macrophage Lab, Department of Microbiology and Immunology, and Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Republic of Korea
- Department of Microbiology and Immunology, and Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jung-Won Kwon
- Department of Microbiology and Immunology, and Institute of Endemic Disease, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jeong Hun Kim
- Fight against Angiogenesis-Related Blindness (FARB) Laboratory, Clinical Research Institute, Seoul National University Hospital, Seoul, Republic of Korea
- Department of Biomedical Sciences, Seoul National University, Seoul, Republic of Korea
- Ophthalmology, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kihwang Lee
- Department of Ophthalmology, Ajou University School of Medicine and Graduate School of Medicine, Suwon, Gyeonggi-do, Republic of Korea
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18
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Di Santo MC, Alaimo A, Domínguez Rubio AP, De Matteo R, Pérez OE. Biocompatibility analysis of high molecular weight chitosan obtained from Pleoticus muelleri shrimps. Evaluation in prokaryotic and eukaryotic cells. Biochem Biophys Rep 2020; 24:100842. [PMID: 33241127 PMCID: PMC7672293 DOI: 10.1016/j.bbrep.2020.100842] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2020] [Revised: 10/19/2020] [Accepted: 10/27/2020] [Indexed: 12/11/2022] Open
Abstract
The search for the exploitation and recycling of biomaterials is increasing for reducing the use of non-renewable resources and minimizing environmental pollution caused by synthetic materials. In this context, Chitosan (CS) being a naturally occurring biopolymer becomes relevant. The aim of the present work was to explore the effects of High Molecular Weight CS (H-CS) from Argentinean shrimp's wastes in prokaryotic and eukaryotic in vitro cell cultures. Ultrastructure of H-CS was analysed by SEM and TEM. In vitro studies were performed in prokaryotic (Lactobacillus casei BL23) and eukaryotic (Caco-2, ARPE-19, EA.hy926 and 3T3-L1) culture cells. High performance microscopic techniques were applied to examine culture cells. No changes in morphology were found in any of the cell types. In addition, fluorescent-dyed H-CS revealed that eukaryotic cells could internalize it optimally. Viability was maintained and proliferation rate even increased for Caco-2, ARPE-19 and 3T3-L1 cells under H-CS treatment. Besides, viability was neither altered in L. casei nor in EA.hy926 cells after H-CS exposure. In conclusion, H-CS could be a suitable biopolymer to be exploited for biomedical or food industry applications.
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Affiliation(s)
- Mariana Carolina Di Santo
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Biológica de La Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Agustina Alaimo
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Biológica de La Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Ana Paula Domínguez Rubio
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Biológica de La Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Regina De Matteo
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Biológica de La Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
| | - Oscar Edgardo Pérez
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
- Instituto de Química Biológica de La Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Consejo Nacional de Investigaciones Científicas y Técnicas, Buenos Aires, Argentina
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19
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Sharma R, Bose D, Maminishkis A, Bharti K. Retinal Pigment Epithelium Replacement Therapy for Age-Related Macular Degeneration: Are We There Yet? Annu Rev Pharmacol Toxicol 2020; 60:553-572. [PMID: 31914900 DOI: 10.1146/annurev-pharmtox-010919-023245] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Pluripotent stem cells (PSCs) are a potential replacement tissue source for degenerative diseases. Age-related macular degeneration (AMD) is a blinding disease triggered by degeneration of the retinal pigment epithelium (RPE), a monolayer tissue that functionally supports retinal photoreceptors. Recently published clinical and preclinical studies have tested PSC-derived RPE as a potential treatment for AMD. Multiple approaches have been used to manufacture RPE cells, to validate them functionally, to confirm their safety profile, and to deliver them to patients either as suspension or as a monolayer patch. Since most of these studies are at an early regulatory approval stage, the primary outcome has been to determine the safety of RPE transplants in patients. However, preliminary signs of efficacy were observed in a few patients. Here, we review the current progress in the PSC-derived RPE transplantation field and provide a comparative assessment of various approaches under development as potential therapeutics for AMD.
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Affiliation(s)
- Ruchi Sharma
- Unit on Ocular and Stem Cell Translational Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Devika Bose
- Unit on Ocular and Stem Cell Translational Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
| | - Arvydas Maminishkis
- Section on Epithelial and Retinal Physiology and Disease, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Kapil Bharti
- Unit on Ocular and Stem Cell Translational Research, National Eye Institute, National Institutes of Health, Bethesda, Maryland 20892, USA;
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20
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Dolinko AH, Chwa M, Atilano SR, Kenney MC. African and Asian Mitochondrial DNA Haplogroups Confer Resistance Against Diabetic Stresses on Retinal Pigment Epithelial Cybrid Cells In Vitro. Mol Neurobiol 2020; 57:1636-1655. [PMID: 31811564 PMCID: PMC7123578 DOI: 10.1007/s12035-019-01834-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 11/12/2019] [Indexed: 01/09/2023]
Abstract
Diabetic retinopathy (DR) is the most common cause of blindness for individuals under the age of 65. This loss of vision can be due to ischemia, neovascularization, and/or diabetic macular edema, which are caused by breakdown of the blood-retina barrier at the level of the retinal pigment epithelium (RPE) and inner retinal vasculature. The prevalence of diabetes and its complications differ between Caucasian-Americans and certain minority populations, such as African-Americans and Asian-Americans. Individuals can be classified by their mitochondrial haplogroups, which are collections of single nucleotide polymorphisms (SNPs) in mitochondrial DNA (mtDNA) representing ancient geographic origins of populations. In this study, we compared the responses of diabetic human RPE cybrids, cell lines containing identical nuclei but mitochondria from either European (maternal European) or maternal African or Asian individuals, to hypoxia and high glucose levels. The African and Asian diabetic ([Afr+Asi]/DM) cybrids showed (1) resistance to both hyperglycemic and hypoxic stresses; (2) downregulation of pro-apoptotic indicator BAX; (3) upregulation of DNA methylation genes, such as DNMT3A and DNMT3B; and (4) resistance to DNA demethylation by the methylation inhibitor 5-Aza-2'-deoxycytidine (5-Aza-dC) compared to European diabetic (Euro/DM) cybrids. Our findings suggest that mitochondria from African and Asian diabetic subjects possess a "metabolic memory" that confers resistance against hyperglycemia, hypoxia, and demethylation, and that this "metabolic memory" can be transferred into the RPE cybrid cell lines in vitro.
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Affiliation(s)
- Andrew H Dolinko
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, 92697, USA
- Department of Ophthalmology Research, Gavin Herbert Eye Institute, University of California Irvine, Hewitt Hall, Room 2028, 843 Health Science Road, Irvine, CA, 92697, USA
| | - Marilyn Chwa
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - Shari R Atilano
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, 92697, USA
| | - M Cristina Kenney
- Department of Pathology and Laboratory Medicine, University of California Irvine, Irvine, CA, 92697, USA.
- Department of Ophthalmology Research, Gavin Herbert Eye Institute, University of California Irvine, Hewitt Hall, Room 2028, 843 Health Science Road, Irvine, CA, 92697, USA.
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21
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Dai Y, Dai C, Sun T. Inflammatory mediators of proliferative vitreoretinopathy: hypothesis and review. Int Ophthalmol 2020; 40:1587-1601. [PMID: 32103371 PMCID: PMC7242233 DOI: 10.1007/s10792-020-01325-4] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Accepted: 02/15/2020] [Indexed: 02/06/2023]
Abstract
Purpose To review the role of inflammatory mediators in proliferative vitreoretinopathy (PVR) development and the current treatment for PVR prevention. Methods A PubMed search was carried out using these keywords “PVR,” “inflammatory mediators,” “growth factors,” “cytokines” and “treatment.” Studies regarding inflammatory mediators and PVR therapy were included and published up to December 2019. Results Inflammatory mediators, namely growth factors and cytokines, have been implicated in the occurrence and development of PVR. Among various inflammatory mediators, transforming growth factor-β, platelet-derived growth factor, interleukin-6, interleukin-8 and tumor necrosis factor-α are considered to be particularly important. In this review, we focus on the hypothesis that growth factors and cytokines are involved in the development of PVR, and current treatment for the prevention of PVR. Conclusion We support the hypothesis that growth factors and cytokines may participate in the complex process of PVR development. More importantly, the identification of inflammatory mediators provides novel and efficacious therapeutic targets for the treatment of PVR.
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Affiliation(s)
- Ying Dai
- Department of Ophthalmology, The First People's Hospital of Yancheng, No. 10, Nancheng River Road, Yancheng, 224000, Jiangsu Province, China
| | - Chenghua Dai
- Department of Ophthalmology, Yangzhou Hospital of Traditional Chinese Medicine Affiliated to Nanjing University of Chinese Medicine, Yangzhou, 225000, Jiangsu Province, China
| | - Tao Sun
- Department of Ophthalmology, The First People's Hospital of Yancheng, No. 10, Nancheng River Road, Yancheng, 224000, Jiangsu Province, China.
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22
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Milićević N, Mazzaro N, de Bruin I, Wils E, Ten Brink J, Asbroek AT, Mendoza J, Bergen A, Felder-Schmittbuhl MP. Rev-Erbα and Photoreceptor Outer Segments modulate the Circadian Clock in Retinal Pigment Epithelial Cells. Sci Rep 2019; 9:11790. [PMID: 31409842 PMCID: PMC6692399 DOI: 10.1038/s41598-019-48203-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2019] [Accepted: 07/30/2019] [Indexed: 12/24/2022] Open
Abstract
Retinal photoreceptor outer segments (POS) are renewed daily through phagocytosis by the adjacent retinal pigment epithelial (RPE) monolayer. Phagocytosis is mainly driven by the RPE circadian clock but the underlying molecular mechanisms remain elusive. Using ARPE-19 (human RPE cell-line) dispersed and monolayer cell cultures, we investigated the influence of cellular organization on the RPE clock and phagocytosis genes. PCR analysis revealed rhythmic expression of clock and phagocytosis genes in all ARPE-19 cultures. Monolayers had a tendency for higher amplitudes of clock gene oscillations. In all conditions ARNTL, CRY1, PER1-2, REV-ERBα, ITGB5, LAMP1 and PROS1 were rhythmically expressed with REV-ERBα being among the clock genes whose expression showed most robust rhythms in ARPE-19 cells. Using RPE-choroid explant preparations of the mPer2Luc knock-in mice we found that Rev-Erbα deficiency induced significantly longer periods and earlier phases of PER2-bioluminescence oscillations. Furthermore, early phagocytosis factors β5-Integrin and FAK and the lysosomal marker LAMP1 protein levels are rhythmic. Finally, POS incubation affects clock and clock-controlled phagocytosis gene expression in RPE monolayers in a time-dependent manner suggesting that POS can reset the RPE clock. These results shed some light on the complex interplay between POS, the RPE clock and clock-controlled phagocytosis machinery which is modulated by Rev-Erbα.
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Affiliation(s)
- Nemanja Milićević
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives (UPR 3212), 67000, Strasbourg, France.,Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Nadia Mazzaro
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives (UPR 3212), 67000, Strasbourg, France
| | - Ivanka de Bruin
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Esmée Wils
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jacoline Ten Brink
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Anneloor Ten Asbroek
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands
| | - Jorge Mendoza
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives (UPR 3212), 67000, Strasbourg, France
| | - Arthur Bergen
- Department of Clinical Genetics, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.,Department of Ophthalmology, Amsterdam UMC, University of Amsterdam, Meibergdreef 9, 1105 AZ, Amsterdam, The Netherlands.,Netherlands Institute for Neuroscience (NIN-KNAW), Amsterdam, The Netherlands
| | - Marie-Paule Felder-Schmittbuhl
- Centre National de la Recherche Scientifique, Université de Strasbourg, Institut des Neurosciences Cellulaires et Intégratives (UPR 3212), 67000, Strasbourg, France.
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Eichler W, Lohrenz A, Simon K, Krohn S, Lange J, Bürger S, Liebscher I. The role of ADGRE5/CD97 in human retinal pigment epithelial cell growth and survival. Ann N Y Acad Sci 2019; 1456:64-79. [DOI: 10.1111/nyas.14210] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2019] [Revised: 06/28/2019] [Accepted: 07/22/2019] [Indexed: 12/27/2022]
Affiliation(s)
| | | | - Kay‐Uwe Simon
- Rudolf Schönheimer Institute of Biochemistry, Molecular BiochemistryLeipzig University Leipzig Germany
| | - Sandra Krohn
- Clinic for Gastroenterology and Rheumatology, Hepatology SectionLeipzig University Leipzig Germany
| | - Johannes Lange
- Norwegian Center for Movement DisordersStavanger University Hospital Stavanger Norway
| | | | - Ines Liebscher
- Rudolf Schönheimer Institute of Biochemistry, Molecular BiochemistryLeipzig University Leipzig Germany
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The Cytoskeleton of the Retinal Pigment Epithelium: from Normal Aging to Age-Related Macular Degeneration. Int J Mol Sci 2019; 20:ijms20143578. [PMID: 31336621 PMCID: PMC6678077 DOI: 10.3390/ijms20143578] [Citation(s) in RCA: 37] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Revised: 07/15/2019] [Accepted: 07/18/2019] [Indexed: 12/15/2022] Open
Abstract
The retinal pigment epithelium (RPE) is a unique epithelium, with major roles which are essential in the visual cycle and homeostasis of the outer retina. The RPE is a monolayer of polygonal and pigmented cells strategically placed between the neuroretina and Bruch membrane, adjacent to the fenestrated capillaries of the choriocapillaris. It shows strong apical (towards photoreceptors) to basal/basolateral (towards Bruch membrane) polarization. Multiple functions are bound to a complex structure of highly organized and polarized intracellular components: the cytoskeleton. A strong connection between the intracellular cytoskeleton and extracellular matrix is indispensable to maintaining the function of the RPE and thus, the photoreceptors. Impairments of these intracellular structures and the regular architecture they maintain often result in a disrupted cytoskeleton, which can be found in many retinal diseases, including age-related macular degeneration (AMD). This review article will give an overview of current knowledge on the molecules and proteins involved in cytoskeleton formation in cells, including RPE and how the cytoskeleton is affected under stress conditions—especially in AMD.
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Cheng SC, Huang WC, S Pang JH, Wu YH, Cheng CY. Quercetin Inhibits the Production of IL-1β-Induced Inflammatory Cytokines and Chemokines in ARPE-19 Cells via the MAPK and NF-κB Signaling Pathways. Int J Mol Sci 2019; 20:ijms20122957. [PMID: 31212975 PMCID: PMC6628093 DOI: 10.3390/ijms20122957] [Citation(s) in RCA: 124] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2019] [Revised: 06/08/2019] [Accepted: 06/13/2019] [Indexed: 12/27/2022] Open
Abstract
Quercetin, a bioflavonoid derived from vegetables and fruits, exerts anti-inflammatory effects in various diseases. Our previous study revealed that quercetin could suppress the expression of matrix metalloprotease-9 (MMP-9) and intercellular adhesion molecule-1 (ICAM-1) to achieve anti-inflammatory effects in tumor necrosis factor-α (TNF-α)-stimulated human retinal pigment epithelial (ARPE-19) cells. The present study explored whether quercetin can inhibit the interleukin-1β (IL-1β)-induced production of inflammatory cytokines and chemokines in ARPE-19 cells. Prior to stimulation by IL-1β, ARPE-19 cells were pretreated with quercetin at various concentrations (2.5–20 µM). The results showed that quercetin could dose-dependently decrease the mRNA and protein levels of ICAM-1, IL-6, IL-8 and monocyte chemoattractant protein-1 (MCP-1). It also attenuated the adherence of the human monocytic leukemia cell line THP-1 to IL-1β-stimulated ARPE-19 cells. We also demonstrated that quercetin inhibited signaling pathways related to the inflammatory process, including phosphorylation of mitogen-activated protein kinases (MAPKs), inhibitor of nuclear factor κ-B kinase (IKK)α/β, c-Jun, cAMP response element-binding protein (CREB), activating transcription factor 2 (ATF2) and nuclear factor (NF)-κB p65, and blocked the translocation of NF-κB p65 into the nucleus. Furthermore, MAPK inhibitors including an extracellular signal-regulated kinase (ERK) 1/2 inhibitor (U0126), a p38 inhibitor (SB202190) and a c-Jun N-terminal kinase (JNK) inhibitor (SP600125) decreased the expression of soluble ICAM-1 (sICAM-1), but not ICAM-1. U0126 and SB202190 could inhibit the expression of IL-6, IL-8 and MCP-1, but SP600125 could not. An NF-κB inhibitor (Bay 11-7082) also reduced the expression of ICAM-1, sICAM-1, IL-6, IL-8 and MCP-1. Taken together, these results provide evidence that quercetin protects ARPE-19 cells from the IL-1β-stimulated increase in ICAM-1, sICAM-1, IL-6, IL-8 and MCP-1 production by blocking the activation of MAPK and NF-κB signaling pathways to ameliorate the inflammatory response.
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Affiliation(s)
- Shu-Chen Cheng
- Department of Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan 33372, Taiwan.
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.
| | - Wen-Chung Huang
- Graduate Institute of Health Industry Technology, Research Center for Chinese Herbal Medicine and Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 33303, Taiwan.
- Division of Allergy, Asthma, and Rheumatology, Department of Pediatrics, Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan.
| | - Jong-Hwei S Pang
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.
- Department of Physical Medicine and Rehabilitation, Chang Gung Memorial Hospital, Taoyuan 33305, Taiwan.
| | - Yi-Hong Wu
- Graduate Institute of Clinical Medical Sciences, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.
- Division of Chinese Internal Medicine, Center for Traditional Chinese Medicine, Chang Gung Memorial Hospital, Taoyuan 33372, Taiwan.
- School of Traditional Chinese Medicine, College of Medicine, Chang Gung University, Taoyuan 33302, Taiwan.
| | - Ching-Yi Cheng
- Graduate Institute of Health Industry Technology, Research Center for Chinese Herbal Medicine and Research Center for Food and Cosmetic Safety, College of Human Ecology, Chang Gung University of Science and Technology, Taoyuan 33303, Taiwan.
- Department of Thoracic Medicine, Chang Gung Memorial Hospital, Linkou 33305, Taiwan.
- Department of Ophthalmology, Chang Gung Memorial Hospital, Linkou 33305, Taiwan.
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Qin D, Jiang Y, Jin X. Effect of macrophage migration inhibitory factor on inflammatory cytokines and fibrogenic gene expression in human RPE cells. Mol Med Rep 2019; 20:830-836. [PMID: 31180524 DOI: 10.3892/mmr.2019.10277] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2018] [Accepted: 04/24/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Dong Qin
- Henan Eye Institute, Henan Provincial Eye Hospital, People's Hospital of Henan Province, Zhengzhou, Henan 450003, P.R. China
| | - Yanrong Jiang
- Department of Ophthalmology, People's Hospital of Peking University, Beijing 100044, P.R. China
| | - Xuemin Jin
- Henan Eye Institute, Henan Provincial Eye Hospital, People's Hospital of Henan Province, Zhengzhou, Henan 450003, P.R. China
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AnandBabu K, Sen P, Angayarkanni N. Oxidized LDL, homocysteine, homocysteine thiolactone and advanced glycation end products act as pro-oxidant metabolites inducing cytokine release, macrophage infiltration and pro-angiogenic effect in ARPE-19 cells. PLoS One 2019; 14:e0216899. [PMID: 31086404 PMCID: PMC6516731 DOI: 10.1371/journal.pone.0216899] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2019] [Accepted: 04/30/2019] [Indexed: 02/03/2023] Open
Abstract
Age-related Macular Degeneration (AMD) is one of the major vision-threatening diseases of the eye. Oxidative stress is one of the key factors in the onset and progression of AMD. In this study, metabolites associated with AMD pathology more so at the systemic level namely, oxidized LDL (oxLDL), homocysteine (Hcy), homocysteine thiolactone (HCTL), advanced glycation end product (AGE) were evaluated for their pro-oxidant nature in a localized ocular environment based on in vitro studies in human retinal pigment epithelial cells (ARPE-19 cells). Human ARPE-19 cells were treated with pro-oxidants 50 μg/mL oxLDL, 500 μM Hcy, 500 nM HCTL, 100 μg/mL AGE, 200 μM H2O2 and 200 μM H2O2 with and without pre-treatment of 5 mM N-acetyl cysteine (NAC). The cytokines IL-6, IL-8 and vascular endothelial growth factor (VEGF) secreted from ARPE-19 cells exposed to pro-oxidants were estimated by ELISA. In vitro angiogenesis assay was performed with conditioned media of the pro-oxidant treated ARPE-19 cells in Geltrex-Matrigel coated 96-well plate. The human acute monocytic leukemia cell line (THP-1) was differentiated into macrophages and its migration in response to conditioned media of ARPE-19 cells insulted with the pro-oxidants was studied by transwell migration assay. Western blot was performed to detect the protein expression of Bax, Bcl-2 and NF-κB to assess apoptotic changes. The compounds involved in the study showed a significant increase in reactive oxygen species (ROS) generation in ARPE-19 cells (oxLDL; Hcy; AGE: p < 0.001 and HCTL: p < 0.05). NAC pre-treatment significantly lowered the oxidative stress brought about by pro-oxidants as seen by lowered ROS and MDA levels in the cells. Treatment with pro-oxidants significantly increased the secretion of IL-6 (oxLDL: p < 0.05; Hcy, HCTL and AGE: p < 0.01) and IL-8 cytokines (oxLDL: p < 0.05; HCTL: p <. 001 and AGE: p < 0.01) in ARPE-19 cells. Serum samples of AMD patients (n = 23) revealed significantly higher IL-6 and IL-8 levels compared to control subjects (n = 23) (IL6: p < 0.01 and IL8: p < 0.05). The pro-oxidants also promoted VEGF secretion by ARPE-19 cells compared to untreated control (oxLDL: p < 0.001; Hcy: p < 0.01; HCTL and AGE: p < 0.05). In vitro angiogenesis assay showed that the conditioned media significantly increased the tube formation in RF/6A endothelial cells. Transwell migration assay revealed significant infiltration of macrophages in response to pro-oxidants. We further demonstrated that the pro-oxidants increased the Bax/Bcl-2 ratio and increased the NF-κB activation resulting in pro-apoptotic changes in ARPE-19 cells. Thus, oxLDL, Hcy, HCTL and AGE act as pro-oxidant metabolites in RPE that promote AMD through oxidative stress, inflammation, chemotaxis and neovascularization.
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Affiliation(s)
- Kannadasan AnandBabu
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, KBIRVO, Vision Research Foundation, Sankara Nethralaya, Chennai, India
- School of Chemical and Biotechnology, SASTRA University, Thanjavur, India
| | - Parveen Sen
- Shri Bhagwan Mahavir Vitreoretinal Services, Sankara Nethralaya, Chennai, India
| | - Narayanasamy Angayarkanni
- R.S. Mehta Jain Department of Biochemistry and Cell Biology, KBIRVO, Vision Research Foundation, Sankara Nethralaya, Chennai, India
- * E-mail: ,
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Milard M, Penhoat A, Durand A, Buisson C, Loizon E, Meugnier E, Bertrand K, Joffre F, Cheillan D, Garnier L, Viel S, Laugerette F, Michalski MC. Acute effects of milk polar lipids on intestinal tight junction expression: towards an impact of sphingomyelin through the regulation of IL-8 secretion? J Nutr Biochem 2019; 65:128-138. [DOI: 10.1016/j.jnutbio.2018.12.007] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 10/30/2018] [Accepted: 12/12/2018] [Indexed: 02/07/2023]
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ten Berge JC, Fazil Z, Born LI, Wolfs RCW, Schreurs MWJ, Dik WA, Rothova A. Intraocular cytokine profile and autoimmune reactions in retinitis pigmentosa, age-related macular degeneration, glaucoma and cataract. Acta Ophthalmol 2019; 97:185-192. [PMID: 30298670 PMCID: PMC6585720 DOI: 10.1111/aos.13899] [Citation(s) in RCA: 78] [Impact Index Per Article: 15.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2017] [Accepted: 07/21/2018] [Indexed: 12/27/2022]
Abstract
Purpose To analyse intraocular cytokine levels and prevalence of intraocular antiretinal antibodies (ARAs) in patients with retinitis pigmentosa (RP), age‐related macular degeneration (AMD), glaucoma and cataract, and correlate the results to clinical manifestations. Methods We collected intraocular fluid samples from patients with RP (n = 25), AMD (n = 12), glaucoma (n = 28) and cataract (n = 22), and serum samples paired with the intraocular fluids from patients with RP (N = 7) and cataract (n = 10). Interleukin (IL)‐1β, IL‐1ra, IL‐2, IL‐6, IL‐6rα, IL‐7, IL‐8, IL‐10, IL‐17A, IL‐23, thymus‐ and activation‐regulated chemokine (TARC), monocyte chemoattractant protein‐1 (MCP‐1), tumour necrosis factor‐alpha (TNF‐α), placental growth factor (PlGF) and vascular endothelial growth factor (VEGF) were measured using a multiplex assay. Antiretinal antibodies (ARA) detection was performed by indirect immunofluorescence. Results Increasing age was associated with increasing levels of IL‐6, IL‐8, TNF‐α and VEGF. All patient groups exhibited distinct profiles of intraocular cytokines. Intraocular levels of IL‐8 were highest in patients with AMD and glaucoma. Cataract patients exhibited high intraocular levels of IL‐23. Intraocular levels of IL‐2, IL‐6, MCP‐1 and PlGF in RP patients exceeded the levels of serum, indicating intraocular production. Intraocular ARAs were found in only one patient with AMD. Conclusion Increased levels of inflammatory cytokines in intraocular fluid of patients with originally noninflammatory ocular diseases show that intraocular inflammation is involved in their pathogenesis of these entities. Moreover, we show that increasing age is associated with increasing levels of intraocular cytokines and conclude that future studies on intraocular mediators should be corrected for age of patients.
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Affiliation(s)
| | - Zainab Fazil
- Department of Ophthalmology Erasmus Medical Center Rotterdam the Netherlands
| | | | - Roger C. W. Wolfs
- Department of Ophthalmology Erasmus Medical Center Rotterdam the Netherlands
| | - Marco W. J. Schreurs
- Department of Immunology Laboratory Medical Immunology Erasmus Medical Center Rotterdam the Netherlands
| | - Wim A. Dik
- Department of Immunology Laboratory Medical Immunology Erasmus Medical Center Rotterdam the Netherlands
| | - Aniki Rothova
- Department of Ophthalmology Erasmus Medical Center Rotterdam the Netherlands
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30
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Dumouchel JL, Chemuturi N, Milton MN, Camenisch G, Chastain J, Walles M, Sasseville V, Gunduz M, Iyer GR, Argikar UA. Models and Approaches Describing the Metabolism, Transport, and Toxicity of Drugs Administered by the Ocular Route. Drug Metab Dispos 2018; 46:1670-1683. [DOI: 10.1124/dmd.118.082974] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2018] [Accepted: 08/10/2018] [Indexed: 11/22/2022] Open
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31
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Sato K, Takeda A, Hasegawa E, Jo YJ, Arima M, Oshima Y, Ryoji Y, Nakazawa T, Yuzawa M, Nakashizuka H, Shimada H, Kimura K, Ishibashi T, Sonoda KH. Interleukin-6 plays a crucial role in the development of subretinal fibrosis in a mouse model. Immunol Med 2018; 41:23-29. [PMID: 30938258 DOI: 10.1080/09114300.2018.1451609] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Subretinal fibrosis has been recognized as a feature of an advanced stage of exudative age-related macular degeneration (AMD) that leads to irreversible loss of vision. This study was aimed at elucidating roles of interlukin-6 (IL-6) in the development of subretinal fibrosis. Immunohistochemistry (IHC) was performed with anti-human IL-6 antibody in surgically excised choroidal neovascular tissues from patients with exudative AMD. The area of subretinal fibrosis was measured in a mouse subretinal fibrosis model with injection of control small interfering RNA(siRNA) or IL-6 siRNA, or isotype control antibody or anti-IL-6 receptor antibody after peritoneal exudative cells (PECs) injection into the vitreous cavity. PECs derived from IL-6+/+ or IL-6-∕- mice were placed into the subretinal space of IL-6+/+ mice. IL-6 was expressed in the stroma and retinal pigment epithelial (RPE) layer in the choroidal neovascular tissues. IL-6 knockdown or blocking of the IL-6 receptor suppressed the formation of subretinal fibroblastic scars. The area of subretinal fibrosis induced by PECs derived from IL-6-∕- mice was less than that induced by PECs from IL-6+/+ mice. The results suggested that IL-6, expressed by activated macrophages, is a crucial mediator that promotes subretinal fibrosis. Targeting IL-6 and the corresponding signaling pathway would be an attractive therapeutic approach not only in choroidal neovascularization, but also in subretinal fibrosis.
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Affiliation(s)
- Kota Sato
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Atsunobu Takeda
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan.,b Clinical Research Center , National Hospital Organization, Kyushu Medical Center , Fukuoka , Japan
| | - Eiichi Hasegawa
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Young-Joon Jo
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Mitsuru Arima
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Yuji Oshima
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Yanai Ryoji
- c Department of Ophthalmology, Graduate School of Medicine , Yamaguchi University , Ube , Yamaguchi , Japan
| | - Toru Nakazawa
- d Department of Ophthalmology, Graduate School of Medicine , Tohoku University , Sendai , Miyagi , Japan
| | - Mitsuko Yuzawa
- e Division of Ophthalmology, Department of Ophthalmology , Nihon University School of Medicine , Tokyo , Japan
| | - Hiroyuki Nakashizuka
- e Division of Ophthalmology, Department of Ophthalmology , Nihon University School of Medicine , Tokyo , Japan
| | - Hiroyuki Shimada
- e Division of Ophthalmology, Department of Ophthalmology , Nihon University School of Medicine , Tokyo , Japan
| | - Kazuhiro Kimura
- c Department of Ophthalmology, Graduate School of Medicine , Yamaguchi University , Ube , Yamaguchi , Japan
| | - Tatsuro Ishibashi
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
| | - Koh-Hei Sonoda
- a Department of Ophthalmology, Graduate School of Medical Sciences , Kyushu University , Fukuoka , Japan
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FACTORS ASSOCIATED WITH VISUAL OUTCOME AFTER MACULA-OFF RHEGMATOGENOUS RETINAL DETACHMENT SURGERY. Retina 2018; 38:137-147. [DOI: 10.1097/iae.0000000000001512] [Citation(s) in RCA: 59] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Hytti M, Andjelic S, Josifovska N, Piippo N, Korhonen E, Hawlina M, Kaarniranta K, Nevalainen TJ, Petrovski G, Parkkari T, Kauppinen A. CB 2 receptor activation causes an ERK1/2-dependent inflammatory response in human RPE cells. Sci Rep 2017; 7:16169. [PMID: 29170454 PMCID: PMC5701010 DOI: 10.1038/s41598-017-16524-w] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2017] [Accepted: 11/13/2017] [Indexed: 12/21/2022] Open
Abstract
A chronic low-level inflammation contributes to the pathogenesis of age-related macular degeneration (AMD), the most common cause of blindness in the elderly in Western countries. The loss of central vision results from attenuated maintenance of photoreceptors due to the degeneration of retinal pigment epithelium (RPE) cells beneath the photoreceptor layer. It has been proposed that pathologic inflammation initiated in RPE cells could be regulated by the activation of type 2 cannabinoid receptors (CB2). Here, we have analysed the effect of CB2 activation on cellular survival and inflammation in human RPE cells. RPE cells were treated with the selective CB2 agonist JWH-133 in the presence or absence of the oxidative stressor 4-hydroxynonenal. Thereafter, cellular viability as well as the release of pro-inflammatory cytokines and potential underlying signalling pathways were analysed. Our results show that JWH-133 led to increased intracellular Ca2+ levels, suggesting that RPE cells are capable of responding to a CB2 agonist. JWH-133 could not prevent oxidative stress-induced cell death. Instead, 10 µM JWH-133 increased cell death and the release of proinflammatory cytokines in an ERK1/2-dependent manner. In contrast to previous findings, CB2 activation increased, rather than reduced inflammation in RPE cells.
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Affiliation(s)
- M Hytti
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland. .,Department of Ophthalmology, School of Medicine, University of Eastern Finland, Kuopio, Finland.
| | - S Andjelic
- Eye Hospital, University Medical Centre, Ljubljana, Slovenia
| | - N Josifovska
- Stem Cells and Eye Research Laboratory, Department of Ophthalmology, Faculty of Medicine, University of Szeged, Szeged, Hungary
| | - N Piippo
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.,Department of Ophthalmology, School of Medicine, University of Eastern Finland, Kuopio, Finland
| | - E Korhonen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland.,Department of Ophthalmology, School of Medicine, University of Eastern Finland, Kuopio, Finland
| | - M Hawlina
- Eye Hospital, University Medical Centre, Ljubljana, Slovenia
| | - K Kaarniranta
- Department of Ophthalmology, School of Medicine, University of Eastern Finland, Kuopio, Finland.,Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - T J Nevalainen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - G Petrovski
- Stem Cells and Eye Research Laboratory, Department of Ophthalmology, Faculty of Medicine, University of Szeged, Szeged, Hungary.,Centre of Eye Research, Department of Ophthalmology and the Norwegian Center for Stem Cell Research, Oslo University Hospital, University of Oslo, Oslo, Norway
| | - T Parkkari
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
| | - A Kauppinen
- School of Pharmacy, University of Eastern Finland, Kuopio, Finland
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Development and characterization of 2-dimensional culture for buffalo intestinal cells. Cytotechnology 2017; 70:361-373. [PMID: 29032508 DOI: 10.1007/s10616-017-0151-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2016] [Accepted: 10/04/2017] [Indexed: 12/16/2022] Open
Abstract
Small intestinal epithelial cells (IEC) play a major role in the absorption of nutrients and toxins. Due to the similarity of genome-wide single copy protein orthologues between cattle and human, establishment of ruminant's primary small IEC culture could be a valuable tool for toxicity studies. Therefore, the current study focused on the development and characterization of buffalo IEC culture, as cattle slaughter is banned in India. The buffalo jejunum fragments were washed consecutively several times in saline, warm phosphate buffered saline (PBS), PBS with 5 mM dithiothreitol, digesting solution and 2% sorbitol in PBS. The cells were cultured on 17 µg/cm2 collagen coated plates and transwell plates with serum (2% Fetal bovine serum (FBS) and 10% FBS) and serum-free culture conditions. The cells were differentiated into typical epithelial cobblestone morphology from day 5 onwards in 50% successful cultures. The cultured IEC were characterized by gene expression of epithelial cell markers, cytokeratin and vimentin, and enterocyte markers like villin, zonula occluden (ZO1), fatty acid binding protein 2 (FABP2) and small intestinal peptidase (IP). Based on the morphology and gene expression profile, 10% FBS has been recommended for culturing primary buffalo IEC on collagen coated plates for 10 days. However, 50% of the successful cultures could not show epithelial phenotype on 10% FBS culture conditions even on collagen coated plates. Interestingly, undifferentiated IEC showed an increasing expression of FABP2, IP and ZO1 transcripts compared to differentiated intestinal cells with 10% FBS on collagen plates. Therefore, future studies are needed to understand the role of FABP2, IP and ZO1 in differentiation of buffalo IEC.
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Ferrington DA, Ebeling MC, Kapphahn RJ, Terluk MR, Fisher CR, Polanco JR, Roehrich H, Leary MM, Geng Z, Dutton JR, Montezuma SR. Altered bioenergetics and enhanced resistance to oxidative stress in human retinal pigment epithelial cells from donors with age-related macular degeneration. Redox Biol 2017; 13:255-265. [PMID: 28600982 PMCID: PMC5466586 DOI: 10.1016/j.redox.2017.05.015] [Citation(s) in RCA: 121] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2017] [Accepted: 05/23/2017] [Indexed: 01/03/2023] Open
Abstract
Age-related macular degeneration (AMD) is the leading cause of blindness among older adults. It has been suggested that mitochondrial defects in the retinal pigment epithelium (RPE) underlies AMD pathology. To test this idea, we developed primary cultures of RPE to ask whether RPE from donors with AMD differ in their metabolic profile compared with healthy age-matched donors. Analysis of gene expression, protein content, and RPE function showed that these cultured cells replicated many of the cardinal features of RPE in vivo. Using the Seahorse Extracellular Flux Analyzer to measure bioenergetics, we observed RPE from donors with AMD exhibited reduced mitochondrial and glycolytic function compared with healthy donors. RPE from AMD donors were also more resistant to oxidative inactivation of these two energy-producing pathways and were less susceptible to oxidation-induced cell death compared with cells from healthy donors. Investigation of the potential mechanism responsible for differences in bioenergetics and resistance to oxidative stress showed RPE from AMD donors had increased PGC1α protein as well as differential expression of multiple genes in response to an oxidative challenge. Based on our data, we propose that cultured RPE from donors phenotyped for the presence or absence of AMD provides an excellent model system for studying "AMD in a dish". Our results are consistent with the ideas that (i) a bioenergetics crisis in the RPE contributes to AMD pathology, and (ii) the diseased environment in vivo causes changes in the cellular profile that are retained in vitro.
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Affiliation(s)
- Deborah A Ferrington
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA; Graduate Program in Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Mara C Ebeling
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Rebecca J Kapphahn
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Marcia R Terluk
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Cody R Fisher
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA; Graduate Program in Biochemistry, Molecular Biology and Biophysics, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Jorge R Polanco
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Heidi Roehrich
- Histology Core for Vision Research, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Michaela M Leary
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Zhaohui Geng
- Stem Cell Institute and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
| | - James R Dutton
- Stem Cell Institute and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
| | - Sandra R Montezuma
- Department of Ophthalmology and Visual Neurosciences, University of Minnesota, Minneapolis, MN 55455, USA.
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Retinal pigment epithelium-secretome: A diabetic retinopathy perspective. Cytokine 2017; 95:126-135. [PMID: 28282610 DOI: 10.1016/j.cyto.2017.02.013] [Citation(s) in RCA: 73] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2016] [Revised: 01/12/2017] [Accepted: 02/14/2017] [Indexed: 12/31/2022]
Abstract
Diabetic retinopathy is a major complication of diabetes mellitus that can lead to retinal vascular abnormalities and visual impairment. While retinal endothelial pathology is well studied, retinal pigment epithelium (RPE) layer modifications and the patho-physiological regulations are not widely understood. The RPE is a highly specialized pigmented layer regulating not only physiological functions such as transport of nutrients, ions, absorption of light, phagocytosis of photoreceptor membranes, but also secretion of a number of cytokines, chemokines, angiogenic and anti-angiogenic factors. The RPE secretome, though crucial in health and disease, remains elusive in diabetic retinopathy. A knowledge of these secreted factors would help explain and correlate the clinical phase of the disease aiding in improved disease management. A comprehensive knowledge of the secreted factors of the RPE is a potential tool for understanding the differential treatment regime of early diabetic retinopathy, diabetic proliferative retinopathy and diabetic macular edema. In this review, we have delineated the importance of factors secreted by the retinal pigment epithelium and its regulation in the pathogenesis of diabetic retinopathy.
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Abstract
Mouse models are powerful tools for the study of ocular diseases. Alterations in the morphology and function of the retinal pigment epithelium (RPE) are common features shared by many ocular disorders. We report a detailed protocol to collect, seed, culture and characterize RPE cells from mice. We describe a reproducible method that we previously developed to collect and culture murine RPE cells on Transwells as functional polarized monolayers. The collection of RPE cells takes ∼3 h, and the cultures mimic in vivo RPE cell features within 1 week. This protocol also describes methods to characterize the cells on Transwells within 1-2 weeks by transmission and scanning electron microscopy (TEM and SEM, respectively), immunostaining of vibratome sections and flat mounts, and measurement of transepithelial electrical resistance. The RPE cell cultures are suitable to study the biology of the RPE from wild-type and genetically modified strains of mice between the ages of 10 d and 12 months. The RPE cells can also be manipulated to investigate molecular mechanisms underlying the RPE pathology in the numerous mouse models of ocular disorders. Furthermore, modeling the RPE pathology in vitro represents a new approach to testing drugs that will help accelerate the development of therapies for vision-threatening disorders such as macular degeneration (MD).
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Shafaie S, Hutter V, Cook MT, Brown MB, Chau DYS. In Vitro Cell Models for Ophthalmic Drug Development Applications. Biores Open Access 2016; 5:94-108. [PMID: 27158563 PMCID: PMC4845647 DOI: 10.1089/biores.2016.0008] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Tissue engineering is a rapidly expanding field that aims to establish feasible techniques to fabricate biologically equivalent replacements for diseased and damaged tissues/organs. Emerging from this prospect is the development of in vitro representations of organs for drug toxicity assessment. Due to the ever-increasing interest in ocular drug delivery as a route for administration as well as the rise of new ophthalmic therapeutics, there is a demand for physiologically accurate in vitro models of the eye to assess drug delivery and safety of new ocular medicines. This review summarizes current existing ocular models and highlights the important factors and limitations that need to be considered during their use.
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Affiliation(s)
- Sara Shafaie
- Department of Pharmacy, Pharmacology, and Postgraduate Medicine, The Research Center in Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire , Hertfordshire, United Kingdom
| | - Victoria Hutter
- Department of Pharmacy, Pharmacology, and Postgraduate Medicine, The Research Center in Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire , Hertfordshire, United Kingdom
| | - Michael T Cook
- Department of Pharmacy, Pharmacology, and Postgraduate Medicine, The Research Center in Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire , Hertfordshire, United Kingdom
| | - Marc B Brown
- Department of Pharmacy, Pharmacology, and Postgraduate Medicine, The Research Center in Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire, Hertfordshire, United Kingdom.; MedPharm Ltd., Guildford, Surrey, United Kingdom
| | - David Y S Chau
- Department of Pharmacy, Pharmacology, and Postgraduate Medicine, The Research Center in Topical Drug Delivery and Toxicology, School of Life and Medical Sciences, University of Hertfordshire , Hertfordshire, United Kingdom
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High-Salt Enhances the Inflammatory Response by Retina Pigment Epithelium Cells following Lipopolysaccharide Stimulation. Mediators Inflamm 2015; 2015:197521. [PMID: 26783382 PMCID: PMC4689981 DOI: 10.1155/2015/197521] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2015] [Revised: 11/10/2015] [Accepted: 11/23/2015] [Indexed: 12/27/2022] Open
Abstract
High-salt has been shown to play a role in the pathogenesis of autoimmune disease. In this study, we investigated the effect of high-salt on the production of inflammatory mediators by ARPE-19 cells and the possible mechanisms involved. ARPE-19 cells were cultured with LPS in DMEM to which extra NaCl had been added (20 mM and 40 mM). NaCl had no influence on the apoptosis and proliferation of ARPE-19. Addition of 40 mM NaCl significantly induced IL-6 and MCP-1 production but had no effect on IL-8 secretion. High mannitol, as an osmotic stress control, did not affect the secretion of inflammatory mediators by ARPE-19 cells indicating that the effect was not mediated by osmolarity. Coculture of ARPE-19 cells with NaCl resulted in significant increases in the phosphorylation of p38 MAPK, Akt, and NF-κB and an upregulation of the transcription factors NFAT5 and SGK1. High-salt significantly promotes IL-6 and MCP-1 production by ARPE-19 cells and is associated with activation of the p38 MAPK, Akt, and NF-κB pathway and NFAT-SGK1 pathways.
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Lueck K, Busch M, Moss SE, Greenwood J, Kasper M, Lommatzsch A, Pauleikhoff D, Wasmuth S. Complement Stimulates Retinal Pigment Epithelial Cells to Undergo Pro-Inflammatory Changes. Ophthalmic Res 2015; 54:195-203. [PMID: 26502094 DOI: 10.1159/000439596] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 08/21/2015] [Indexed: 11/19/2022]
Abstract
BACKGROUND/AIMS We examined the effect of human complement sera (HCS) on retinal pigment epithelial (RPE) cells with respect to pro-inflammatory mediators relevant in early age-related macular degeneration (AMD). METHODS RPE cells were treated with complement-containing HCS or with heat-inactivated (HI) HCS or C7-deficient HCS as controls. Cells were analysed for C5b-9 using immunocytochemistry and flow cytometry. Interleukin (IL)-6, IL-8, and monocyte chemoattractant protein-1 (MCP-1) were quantified by ELISA and RT-PCR. Tumour necrosis factor-α (TNF-α), intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1), were analysed by Western blotting. The intracellular distribution of nuclear factor (NF)-x03BA;B was investigated by immunofluorescence. RESULTS A concentration-dependent increased staining for C5b-9 but no influence on cell viability was observed after HCS treatment. ELISA and RT-PCR analysis revealed elevated secretion and expression of IL-6, IL-8, and MCP-1. Western blot analysis showed a concentration-dependent increase in ICAM-1, VCAM-1, and TNF-α in response to HCS, and immunofluorescence staining revealed nuclear translocation of NF-x03BA;B. CONCLUSION This study suggests that complement stimulates NF-x03BA;B activation in RPE cells that might further create a pro-inflammatory environment. All these factors together may support early AMD development.
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Affiliation(s)
- Katharina Lueck
- Ophtha-Lab, Department of Ophthalmology at St. Franziskus Hospital, Muenster, Germany
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Piippo N, Korkmaz A, Hytti M, Kinnunen K, Salminen A, Atalay M, Kaarniranta K, Kauppinen A. Decline in cellular clearance systems induces inflammasome signaling in human ARPE-19 cells. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2014; 1843:3038-46. [PMID: 25268952 DOI: 10.1016/j.bbamcr.2014.09.015] [Citation(s) in RCA: 56] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 05/28/2014] [Revised: 09/15/2014] [Accepted: 09/16/2014] [Indexed: 11/25/2022]
Abstract
Retinal pigment epithelium (RPE) plays a major role in the maintenance of photoreceptors, and degeneration of RPE results in the development of age-related macular degeneration (AMD). Accumulation of intracellular protein aggregates, increased oxidative stress, and chronic inflammation are all factors damaging the functionality of aged RPE cells. Here, we report that inhibition of proteasomal degradation with MG-132 and autophagy with bafilomycin A1 resulted in the release of IL-1β but not that of IL-18 in human ARPE-19 cells. NLRP3 receptor became upregulated, and caspase-1, the functional component of an inflammasome complex, was activated. In addition to accumulating intracellular protein aggregates, inhibition of degradation systems induced oxidative stress which was demonstrated by elevated amounts of intracellular 4-hydroxynonenal (HNE)-protein adducts. Along with IL-1β, exposure to MG-132 and bafilomycin A1 resulted in the secretion of IL-8. A low concentration (1pg/ml) of IL-1β was capable of triggering significant IL-8 production which also became attenuated by treatment with a specific caspase-1 inhibitor. These results suggest that decline in intracellular degradation systems results not only in increased amounts of intracellular protein aggregates and oxidative stress but also in the activation of NLRP3 inflammasomes, arisen as a result of elevated production of biologically active IL-1β.
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Affiliation(s)
- Niina Piippo
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Ayhan Korkmaz
- Institute of Biomedicine, Physiology, University of Eastern Finland, Kuopio, Finland
| | - Maria Hytti
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland
| | - Kati Kinnunen
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Antero Salminen
- Department of Neurology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Department of Neurology, Kuopio University Hospital, Kuopio, Finland
| | - Mustafa Atalay
- Institute of Biomedicine, Physiology, University of Eastern Finland, Kuopio, Finland
| | - Kai Kaarniranta
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland
| | - Anu Kauppinen
- Department of Ophthalmology, Institute of Clinical Medicine, University of Eastern Finland, Kuopio, Finland; Department of Ophthalmology, Kuopio University Hospital, Kuopio, Finland.
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Kuznetsova AV, Kurinov AM, Aleksandrova MA. Cell models to study regulation of cell transformation in pathologies of retinal pigment epithelium. J Ophthalmol 2014; 2014:801787. [PMID: 25177495 PMCID: PMC4142280 DOI: 10.1155/2014/801787] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Revised: 06/16/2014] [Accepted: 06/30/2014] [Indexed: 11/25/2022] Open
Abstract
The retinal pigment epithelium (RPE) plays a key role in the development of many eye diseases leading to visual impairment and even blindness. Cell culture models of pathological changes in the RPE make it possible to study factors responsible for these changes and signaling pathways coordinating cellular and molecular mechanisms of cell interactions under pathological conditions. Moreover, they give an opportunity to reveal target cells and develop effective specific treatment for degenerative and dystrophic diseases of the retina. In this review, data are presented on RPE cell sources for culture models, approaches to RPE cell culturing, phenotypic changes of RPE cells in vitro, the role of signal pathways, and possibilities for their regulation in pathological processes.
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Affiliation(s)
- Alla V. Kuznetsova
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
| | - Alexander M. Kurinov
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
| | - Maria A. Aleksandrova
- N.K. Koltsov Institute of Developmental Biology, Russian Academy of Sciences, ul. Vavilova 26, Moscow 119334, Russia
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Kuznetsova AV. Morphological and physiological characteristics of the native retinal pigment epithelium in vertebrate animals and human. ACTA ACUST UNITED AC 2014. [DOI: 10.1134/s2079086414020030] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Cui W, Zhang H, Liu ZL. Interleukin-6 receptor blockade suppresses subretinal fibrosis in a mouse model. Int J Ophthalmol 2014; 7:194-7. [PMID: 24790857 DOI: 10.3980/j.issn.2222-3959.2014.02.02] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2013] [Accepted: 01/29/2014] [Indexed: 11/02/2022] Open
Abstract
AIM To determine the involvement of the interleukin (IL)-6 with the development of experimental subretinal fibrosis in a mouse model. METHODS Subretinal fibrosis was induced by subretinal injection of macrophage-rich peritoneal exudate cells and the local expression of IL-6 was assessed by quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbent assay (ELISA) at various time points. In addition, we investigated the effect of IL-6 receptor (IL-6R) monoclonal antibody (MR16-1) on subretinal fibrosis development. RESULTS IL-6 mRNA level was significantly elevated at 1d after subretinal fibrosis induction and increased further to about 12-fold at 2d, reaching the peak. The result of ELISA showed that IL-6 protein was not detected in naive mice. At 2d after subretinal fibrosis induction, IL-6 protein level was upregulated to 67.33±14.96 pg/mg in subretinal fibrosis mice. MR16-1 treatment resulted in a reduced subretinal fibrosis area by 48% compared to animals from control group at 7d. CONCLUSION Our results indicated that IL-6 signaling may contribute to the pathogenesis of subretinal fibrogenesis and IL-6R inhibition may provide an effective, novel treatment of advanced and late-stage neovascular age-related macular degeneration.
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Affiliation(s)
- Wei Cui
- Department of Ophthalmology, the First Hospital of China Medical University, Shenyang 110001, Liaoning Province, China
| | - Han Zhang
- Department of Ophthalmology, the First Hospital of China Medical University, Shenyang 110001, Liaoning Province, China
| | - Zhe-Li Liu
- Department of Ophthalmology, the First Hospital of China Medical University, Shenyang 110001, Liaoning Province, China
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Beta cyclodextrins bind, stabilize, and remove lipofuscin bisretinoids from retinal pigment epithelium. Proc Natl Acad Sci U S A 2014; 111:E1402-8. [PMID: 24706818 DOI: 10.1073/pnas.1400530111] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023] Open
Abstract
Accumulation of lipofuscin bisretinoids (LBs) in the retinal pigment epithelium (RPE) is the alleged cause of retinal degeneration in genetic blinding diseases (e.g., Stargardt) and a possible etiological agent for age-related macular degeneration. Currently, there are no approved treatments for these diseases; hence, agents that efficiently remove LBs from RPE would be valuable therapeutic candidates. Here, we show that beta cyclodextrins (β-CDs) bind LBs and protect them against oxidation. Computer modeling and biochemical data are consistent with the encapsulation of the retinoid arms of LBs within the hydrophobic cavity of β-CD. Importantly, β-CD treatment reduced by 73% and 48% the LB content of RPE cell cultures and of eyecups obtained from Abca4-Rdh8 double knock-out (DKO) mice, respectively. Furthermore, intravitreal administration of β-CDs reduced significantly the content of bisretinoids in the RPE of DKO animals. Thus, our results demonstrate the effectiveness of β-CDs to complex and remove LB deposits from RPE cells and provide crucial data to develop novel prophylactic approaches for retinal disorders elicited by LBs.
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46
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Shah K, McCormack CE, Bradbury NA. Do you know the sex of your cells? Am J Physiol Cell Physiol 2014; 306:C3-18. [PMID: 24196532 PMCID: PMC3919971 DOI: 10.1152/ajpcell.00281.2013] [Citation(s) in RCA: 143] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2013] [Accepted: 10/31/2013] [Indexed: 11/22/2022]
Abstract
Do you know the sex of your cells? Not a question that is frequently heard around the lab bench, yet thanks to recent research is probably one that should be asked. It is self-evident that cervical epithelial cells would be derived from female tissue and prostate cells from a male subject (exemplified by HeLa and LnCaP, respectively), yet beyond these obvious examples, it would be true to say that the sex of cell lines derived from non-reproductive tissue, such as lung, intestine, kidney, for example, is given minimal if any thought. After all, what possible impact could the presence of a Y chromosome have on the biochemistry and cell biology of tissues such as the exocrine pancreatic acini? Intriguingly, recent evidence has suggested that far from being irrelevant, genes expressed on the sex chromosomes can have a marked impact on the biology of such diverse tissues as neurons and renal cells. It is also policy of AJP-Cell Physiology that the source of all cells utilized (species, sex, etc.) should be clearly indicated when submitting an article for publication, an instruction that is rarely followed (http://www.the-aps.org/mm/Publications/Info-For-Authors/Composition). In this review we discuss recent data arguing that the sex of cells being used in experiments can impact the cell's biology, and we provide a table outlining the sex of cell lines that have appeared in AJP-Cell Physiology over the past decade.
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Affiliation(s)
- Kalpit Shah
- Department of Physiology and Biophysics, Chicago Medical School, Rosalind Franklin University of Medicine and Science, North Chicago, Illinois
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47
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Klotho regulates retinal pigment epithelial functions and protects against oxidative stress. J Neurosci 2013; 33:16346-59. [PMID: 24107965 DOI: 10.1523/jneurosci.0402-13.2013] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
The retinal pigment epithelium (RPE) is a highly specialized CNS tissue that plays crucial roles in retinal homeostasis. Age-related morphological changes in the RPE have been associated with retinal degenerative disorders; our understanding of the underlying molecular mechanisms, however, remains incomplete. Here we report on a key role of Klotho (Kl), an aging-suppressor gene, in retinal health and RPE physiology. Kl(-/-) mice show RPE and photoreceptor degeneration, reduced pigment synthesis in the RPE, and impaired phagocytosis of the outer segment of the photoreceptors. Klotho protein (KL) is expressed in primary cultured human RPE, and regulates pigment synthesis by increasing the expression of MITF (microphthalmia transcription factor) and TYR (tyrosinase), two pivotal genes in melanogenesis. Importantly, KL increases phagocytosis in cultured RPE by inducing gene expression of MERTK/AXL/TYRO3. These effects of KL are mediated through cAMP-PKA-dependent phosphorylation of transcription factor CREB. In cultured human RPE, KL increases the l-3,4-dihydroxyphenylalanine synthesis and inhibits vascular endothelial growth factor (VEGF) secretion from basal membrane by inhibiting IGF-1 signaling and VEGF receptor 2 phosphorylation. KL also regulates the expression of stress-related genes in RPE, lowers the production of reactive oxygen species, and thereby, protects RPE from oxidative stress. Together, our results demonstrate a critical function for KL in mouse retinal health in vivo, and a protective role toward human RPE cells in vitro. We conclude that KL is an important regulator of RPE homeostasis, and propose that an age-dependent decline of KL expression may contribute to RPE degeneration and retinal pathology.
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48
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Rossi O, Karczewski J, Stolte EH, Brummer RJM, van Nieuwenhoven MA, Meijerink M, van Neerven JRJ, van Ijzendoorn SCD, van Baarlen P, Wells JM. Vectorial secretion of interleukin-8 mediates autocrine signalling in intestinal epithelial cells via apically located CXCR1. BMC Res Notes 2013; 6:431. [PMID: 24164922 PMCID: PMC4231470 DOI: 10.1186/1756-0500-6-431] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Accepted: 09/25/2013] [Indexed: 12/20/2022] Open
Abstract
Background In the intestinal mucosa, several adaptations of TLR signalling have evolved to avoid chronic inflammatory responses to the presence of commensal microbes. Here we investigated whether polarized monolayers of intestinal epithelial cells might regulate inflammatory responses by secreting IL-8 in a vectorial fashion (i.e. apical versus basolateral) depending on the location of the TLR stimulus. Results In the Caco-2 BBE model of polarized villus-like epithelium, apical stimulation with TLR2 and TLR5 ligands resulted in the apical secretion of IL-8. The CXCR1 receptor for IL-8 was expressed only on the apical membrane of Caco-2 BBE cells and differentiated epithelial cells in the human small intestine and colon. Transcriptome analyses revealed that Caco-2 BBE cells respond to stimulation with IL-8 supporting the hypothesis that IL-8 induces G protein-coupled receptor signalling. Conclusions These results show that IL-8 induces autocrine signalling via an apical CXCR1 in Caco-2 BBE intestinal epithelial cells and that this receptor is also expressed on the apical surface of differentiated human intestinal epithelial cells in vivo, suggesting an autocrine function for IL-8 secreted in the lumen.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Jerry M Wells
- Host-Microbe Interactomics Group, ASG, University of Wageningen, Wageningen, The Netherlands.
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Bonilha VL. Retinal pigment epithelium (RPE) cytoskeleton in vivo and in vitro. Exp Eye Res 2013; 126:38-45. [PMID: 24090540 DOI: 10.1016/j.exer.2013.09.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2013] [Revised: 09/18/2013] [Accepted: 09/19/2013] [Indexed: 12/31/2022]
Abstract
The retinal pigment epithelium (RPE) constitutes a monolayer of cuboidal cells that interact apically with the interphotoreceptor matrix (IPM) and outer segments of the photoreceptor cells and basally with the subjacent Bruch's membrane. This highly polarized structure is maintained by the cytoskeleton of individual cells and their interactions at the basolateral junctional complexes that stabilize this epithelial structure. This RPE complex network of filaments, tubules and associated proteins is modeled by the cellular environment, the RPE intercellular interactions, and by its interactions with the extracellular matrix. This is a review of the key features of the RPE cytoskeleton in vivo and in vitro.
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Affiliation(s)
- Vera L Bonilha
- Department of Ophthalmic Research, The Cole Eye Institute, Cleveland Clinic Lerner College of Medicine, 9500 Euclid Avenue i31, Cleveland, OH 44195, USA.
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50
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A2E induces IL-1ß production in retinal pigment epithelial cells via the NLRP3 inflammasome. PLoS One 2013; 8:e67263. [PMID: 23840644 PMCID: PMC3696103 DOI: 10.1371/journal.pone.0067263] [Citation(s) in RCA: 104] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2012] [Accepted: 05/20/2013] [Indexed: 11/19/2022] Open
Abstract
AIMS With ageing extracellular material is deposited in Bruch's membrane, as drusen. Lipofuscin is deposited in retinal pigment epithelial cells. Both of these changes are associated with age related macular degeneration, a disease now believed to involve chronic inflammation at the retinal-choroidal interface. We hypothesise that these molecules may act as danger signals, causing the production of inflammatory chemokines and cytokines by the retinal pigment epithelium, via activation of pattern recognition receptors. METHODS ARPE-19 cells were stimulated in vitro with the following reported components of drusen: amyloid-ß (1-42), Carboxyethylpyrrole (CEP) modified proteins (CEP-HSA), Nε-(Carboxymethyl)lysine (CML) modified proteins and aggregated vitronectin. The cells were also stimulated with the major fluorophore of lipofuscin: N-retinylidene-N-retinylethanolamine (A2E). Inflammatory chemokine and cytokine production was assessed using Multiplex assays and ELISA. The mechanistic evaluation of the NLRP3 inflammasome pathway was assessed in a stepwise fashion. RESULTS Of all the molecules tested only A2E induced inflammatory chemokine and cytokine production. 25 µM A2E induced the production of significantly increased levels of the chemokines IL-8, MCP-1, MCG and MIP-1α, the cytokines IL-1ß, IL-2, IL-6, and TNF-α, and the protein VEGF-A. The release of IL-1ß was studied further, and was determined to be due to NLRP3 inflammasome activation. The pathway of activation involved endocytosis of A2E, and the three inflammasome components NLRP3, ASC and activated caspase-1. Immunohistochemical staining of ABCA4 knockout mice, which show progressive accumulation of A2E levels with age, showed increased amounts of IL-1ß proximal to the retinal pigment epithelium. CONCLUSIONS A2E has the ability to stimulate inflammatory chemokine and cytokine production by RPE cells. The pattern recognition receptor NLRP3 is involved in this process. This provides further evidence for the link between A2E, inflammation, and the pathogenesis of AMD. It also supports the recent discovery of NLRP3 inflammasome activation in AMD.
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