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Cavalu S, Saber S, Ramadan A, Elmorsy EA, Hamad RS, Abdel-Reheim MA, Youssef ME. Unveiling citicoline's mechanisms and clinical relevance in the treatment of neuroinflammatory disorders. FASEB J 2024; 38:e70030. [PMID: 39221499 DOI: 10.1096/fj.202400823r] [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: 04/11/2024] [Revised: 08/07/2024] [Accepted: 08/20/2024] [Indexed: 09/04/2024]
Abstract
Citicoline, a compound produced naturally in small amounts in the human body, assumes a pivotal role in phosphatidylcholine synthesis, a dynamic constituent of membranes of neurons. Across diverse models of brain injury and neurodegeneration, citicoline has demonstrated its potential through neuroprotective and anti-inflammatory effects. This review aims to elucidate citicoline's anti-inflammatory mechanism and its clinical implications in conditions such as ischemic stroke, head trauma, glaucoma, and age-associated memory impairment. Citicoline's anti-inflammatory prowess is rooted in its ability to stabilize cellular membranes, thereby curbing the excessive release of glutamate-a pro-inflammatory neurotransmitter. Moreover, it actively diminishes free radicals and inflammatory cytokines productions, which could otherwise harm neurons and incite neuroinflammation. It also exhibits the potential to modulate microglia activity, the brain's resident immune cells, and hinder the activation of NF-κB, a transcription factor governing inflammatory genes. Clinical trials have subjected citicoline to rigorous scrutiny in patients grappling with acute ischemic stroke, head trauma, glaucoma, and age-related memory impairment. While findings from these trials are mixed, numerous studies suggest that citicoline could confer improvements in neurological function, disability reduction, expedited recovery, and cognitive decline prevention within these cohorts. Additionally, citicoline boasts a favorable safety profile and high tolerability. In summary, citicoline stands as a promising agent, wielding both neuroprotective and anti-inflammatory potential across a spectrum of neurological conditions. However, further research is imperative to delineate the optimal dosage, treatment duration, and underlying mechanisms. Moreover, identifying specific patient subgroups most likely to reap the benefits of citicoline as a new therapy remains a critical avenue for exploration.
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Affiliation(s)
- Simona Cavalu
- Faculty of Medicine and Pharmacy, University of Oradea, Oradea, Romania
| | - Sameh Saber
- Department of Pharmacology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, Egypt
| | - Asmaa Ramadan
- Department of Biochemistry, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, Egypt
| | - Elsayed A Elmorsy
- Department of Pharmacology and Therapeutics, College of Medicine, Qassim University, Buraidah, Saudi Arabia
| | - Rabab S Hamad
- Biological Sciences Department, College of Science, King Faisal University, Al Ahsa, Saudi Arabia
- Central Laboratory, Theodor Bilharz Research Institute, Giza, Egypt
| | - Mustafa Ahmed Abdel-Reheim
- Department of Pharmaceutical Sciences, College of Pharmacy, Shaqra University, Shaqra, Saudi Arabia
- Department of Pharmacology and Toxicology, Faculty of Pharmacy, Beni-Suef University, Beni Suef, Egypt
| | - Mahmoud E Youssef
- Department of Pharmacology, Faculty of Pharmacy, Delta University for Science and Technology, Gamasa, Egypt
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Mirzahosseini G, Adam JM, Nasoohi S, El-Remessy AB, Ishrat T. Lost in Translation: Neurotrophins Biology and Function in the Neurovascular Unit. Neuroscientist 2023; 29:694-714. [PMID: 35769016 DOI: 10.1177/10738584221104982] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
The neurovascular unit (NVU) refers to the functional building unit of the brain and the retina, where neurons, glia, and microvasculature orchestrate to meet the demand of the retina's and brain's function. Neurotrophins (NTs) are structural families of secreted proteins and are known for exerting neurotrophic effects on neuronal differentiation, survival, neurite outgrowth, synaptic formation, and plasticity. NTs include several molecules, such as nerve growth factor, brain-derived neurotrophic factor, NT-3, NT-4, and their precursors. Furthermore, NTs are involved in signaling pathways such as inflammation, apoptosis, and angiogenesis in a nonneuronal cell type. Interestingly, NTs and the precursors can bind and activate the p75 neurotrophin receptor (p75NTR) at low and high affinity. Mature NTs bind their cognate tropomyosin/tyrosine-regulated kinase receptors, crucial for maintenance and neuronal development in the brain and retina axis. Activation of p75NTR results in neuronal apoptosis and cell death, while tropomysin receptor kinase upregulation contributes to differentiation and cell growth. Recent findings indicate that modulation of NTs and their receptors contribute to neurovascular dysfunction in the NVU. Several chronic metabolic and acute ischemic diseases affect the NVU, including diabetic and ischemic retinopathy for the retina, as well as stroke, acute encephalitis, and traumatic brain injury for the brain. This work aims to review the current evidence through published literature studying the impact of NTs and their receptors, including the p75NTR receptor, on the injured and healthy brain-retina axis.
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Affiliation(s)
- Golnoush Mirzahosseini
- Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Justin Mark Adam
- Department of Medicine, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
| | - Sanaz Nasoohi
- Neuroscience Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | | | - Tauheed Ishrat
- Department of Anatomy and Neurobiology, College of Medicine, University of Tennessee Health Science Center, Memphis, TN, USA
- Department of Pharmaceutical Sciences, College of Pharmacy, University of Tennessee Health Science Center, Memphis, TN, USA
- Neuroscience Institute, University of Tennessee Health Science Center, Memphis, TN, USA
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Oshitari T. Neurovascular Cell Death and Therapeutic Strategies for Diabetic Retinopathy. Int J Mol Sci 2023; 24:12919. [PMID: 37629100 PMCID: PMC10454228 DOI: 10.3390/ijms241612919] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2023] [Revised: 08/11/2023] [Accepted: 08/17/2023] [Indexed: 08/27/2023] Open
Abstract
Diabetic retinopathy (DR) is a major complication of diabetes and a leading cause of blindness worldwide. DR was recently defined as a neurovascular disease associated with tissue-specific neurovascular impairment of the retina in patients with diabetes. Neurovascular cell death is the main cause of neurovascular impairment in DR. Thus, neurovascular cell protection is a potential therapy for preventing the progression of DR. Growing evidence indicates that a variety of cell death pathways, such as apoptosis, necroptosis, ferroptosis, and pyroptosis, are associated with neurovascular cell death in DR. These forms of regulated cell death may serve as therapeutic targets for ameliorating the pathogenesis of DR. This review focuses on these cell death mechanisms and describes potential therapies for the treatment of DR that protect against neurovascular cell death.
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Affiliation(s)
- Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Japan; ; Tel.: +81-43-226-2124; Fax: +81-43-224-4162
- Department of Ophthalmology, School of Medicine, International University of Health and Welfare, 4-3 Kozunomori, Narita 286-8686, Japan
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Tatsumi T. Current Treatments for Diabetic Macular Edema. Int J Mol Sci 2023; 24:ijms24119591. [PMID: 37298544 DOI: 10.3390/ijms24119591] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 05/29/2023] [Accepted: 05/30/2023] [Indexed: 06/12/2023] Open
Abstract
Diabetic retinopathy is a major retinal disorder and a leading cause of blindness. Diabetic macular edema (DME) is an ocular complication in patients with diabetes, and it can impair vision significantly. DME is a disorder of the neurovascular system, and it causes obstructions of the retinal capillaries, damage of the blood vessels, and hyperpermeability due to the expression and action of vascular endothelial growth factor (VEGF). These changes result in hemorrhages and leakages of the serous components of blood that result in failures of the neurovascular units (NVUs). Persistent edema of the retina around the macula causes damage to the neural cells that constitute the NVUs resulting in diabetic neuropathy of the retina and a reduction in vision quality. The macular edema and NVU disorders can be monitored by optical coherence tomography (OCT). Neuronal cell death and axonal degeneration are irreversible, and their development can result in permanent visual loss. Treating the edema before these changes are detected in the OCT images is necessary for neuroprotection and maintenance of good vision. This review describes the effective treatments for the macular edema that are therefore neuroprotective.
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Affiliation(s)
- Tomoaki Tatsumi
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Japan
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Advanced Glycation End-Products and Diabetic Neuropathy of the Retina. Int J Mol Sci 2023; 24:ijms24032927. [PMID: 36769249 PMCID: PMC9917392 DOI: 10.3390/ijms24032927] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2022] [Revised: 01/29/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023] Open
Abstract
Diabetic retinopathy is a tissue-specific neurovascular impairment of the retina in patients with both type 1 and type 2 diabetes. Several pathological factors are involved in the progressive impairment of the interdependence between cells that consist of the neurovascular units (NVUs). The advanced glycation end-products (AGEs) are one of the major pathological factors that cause the impairments of neurovascular coupling in diabetic retinopathy. Although the exact mechanisms for the toxicities of the AGEs in diabetic retinopathy have not been definitively determined, the AGE-receptor of the AGE (RAGE) axis, production of reactive oxygen species, inflammatory reactions, and the activation of the cell death pathways are associated with the impairment of the NVUs in diabetic retinopathy. More specifically, neuronal cell death is an irreversible change that is directly associated with vision reduction in diabetic patients. Thus, neuroprotective therapies must be established for diabetic retinopathy. The AGEs are one of the therapeutic targets to examine to ameliorate the pathological changes in the NVUs in diabetic retinopathy. This review focuses on the basic and pathological findings of AGE-induced neurovascular abnormalities and the potential therapeutic approaches, including the use of anti-glycated drugs to protect the AGE-induced impairments of the NVUs in diabetic retinopathy.
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Xu K, Yu L, Wang Z, Lin P, Zhang N, Xing Y, Yang N. Use of gene therapy for optic nerve protection: Current concepts. Front Neurosci 2023; 17:1158030. [PMID: 37090805 PMCID: PMC10117674 DOI: 10.3389/fnins.2023.1158030] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Accepted: 03/20/2023] [Indexed: 04/25/2023] Open
Abstract
Gene therapy has become an essential treatment for optic nerve injury (ONI) in recent years, and great strides have been made using animal models. ONI, which is characterized by the loss of retinal ganglion cells (RGCs) and axons, can induce abnormalities in the pupil light reflex, visual field defects, and even vision loss. The eye is a natural organ to target with gene therapy because of its high accessibility and certain immune privilege. As such, numerous gene therapy trials are underway for treating eye diseases such as glaucoma. The aim of this review was to cover research progress made in gene therapy for ONI. Specifically, we focus on the potential of gene therapy to prevent the progression of neurodegenerative diseases and protect both RGCs and axons. We cover the basic information of gene therapy, including the classification of gene therapy, especially focusing on genome editing therapy, and then we introduce common editing tools and vector tools such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) -Cas9 and adeno-associated virus (AAV). We also summarize the progress made on understanding the roles of brain derived neurotrophic factor (BDNF), ciliary neurotrophic factor (CNTF), phosphatase-tensin homolog (PTEN), suppressor of cytokine signal transduction 3 (SOCS3), histone acetyltransferases (HATs), and other important molecules in optic nerve protection. However, gene therapy still has many challenges, such as misalignment and mutations, immunogenicity of AAV, time it takes and economic cost involved, which means that these issues need to be addressed before clinical trials can be considered.
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Affiliation(s)
- Kexin Xu
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Lu Yu
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Department of Ophthalmology, Aier Eye Hospital of Wuhan University, Wuhan, Hubei, China
| | - Zhiyi Wang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Pei Lin
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Ningzhi Zhang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
| | - Yiqiao Xing
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Department of Ophthalmology, Aier Eye Hospital of Wuhan University, Wuhan, Hubei, China
- *Correspondence: Yiqiao Xing,
| | - Ning Yang
- Department of Ophthalmology, Renmin Hospital of Wuhan University, Wuhan, Hubei, China
- Ning Yang,
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Mastropasqua L, Agnifili L, Ferrante C, Sacchi M, Figus M, Rossi GCM, Brescia L, Aloia R, Orlando G. Citicoline/Coenzyme Q10/Vitamin B3 Fixed Combination Exerts Synergistic Protective Effects on Neuronal Cells Exposed to Oxidative Stress. Nutrients 2022; 14:nu14142963. [PMID: 35889920 PMCID: PMC9316190 DOI: 10.3390/nu14142963] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Revised: 07/14/2022] [Accepted: 07/17/2022] [Indexed: 11/17/2022] Open
Abstract
Background: The present study aimed to investigate the rationale and efficacy of using a citicoline, coenzyme Q10 (CAVAQ10) and vitamin B3 fixed combination in combating inflammation and oxidation in neuronal cells exposed to oxidative stress. Methods: HypoE22 cells and isolated hypothalamic specimens were selected as in vitro models to conduct the experiments. The efficacy of citicoline, CAVAQ10, and vitamin B3, with their fixed combination, were assayed after the exposure of hypothalamic cells to hydrogen peroxide (concentration range 1 nM–10 µM), in order to evaluate the biocompatibility of treatments. The activity of neuroprotective and pro-inflammatory factors, namely, brain-derived neurotrophic factor (BDNF), interleukin-6 (IL-6), and tumor necrosis factor-α (TNFα), involved in the neuronal cell damage in neurodegenerative diseases, were assayed in isolated hypothalamus. Results: Neither citicoline, CAVAQ10, nor vitamin B3 significantly altered hypothalamic cell viability, thus suggesting the biocompatibility of single ingredients and fixed combination in the concentration range considered for the study. In the same condition, citicoline and CAVAQ10 were also effective in reducing the gene expression of monoaminoxidase-B, involved in dopamine degradation. However, only citicoline demonstrated an ability to reduce dopamine levels. Conversely, all compounds were effective in reducing the gene expression of IL-6, and TNFα, and in inducing the gene expression of BDNF, with the co-administration of citicoline/CAVAQ10/vitamin B3 being generally more effective than single ingredients. Conclusions: The present findings support the beneficial and synergistic effects of citicoline, CAVAQ10, and vitamin B3 in fixed combination in reducing inflammation and oxidation, and in stimulating neurotrophin production in neuronal cells.
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Affiliation(s)
- Leonardo Mastropasqua
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy; (L.M.); (R.A.)
| | - Luca Agnifili
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy; (L.M.); (R.A.)
- Correspondence: (L.A.); (L.B.); Tel.: +39-0871-358489 (L.A. & L.B.); Fax: +39-0871-358794 (L.A. & L.B.)
| | - Claudio Ferrante
- Department of Pharmacy, G. d’Annunzio University, 66013 Chieti, Italy; (C.F.); (G.O.)
| | - Matteo Sacchi
- University Eye Clinic, San Giuseppe Hospital, IRCCS Multimedica, 20900 Milan, Italy;
| | - Michele Figus
- Ophthalmology Unit, Department of Surgery, Medicine, Molecular and Emergency, University of Pisa, 56124 Pisa, Italy;
| | | | - Lorenza Brescia
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy; (L.M.); (R.A.)
- Correspondence: (L.A.); (L.B.); Tel.: +39-0871-358489 (L.A. & L.B.); Fax: +39-0871-358794 (L.A. & L.B.)
| | - Raffaella Aloia
- Ophthalmology Clinic, Department of Medicine and Aging Science, University G. d’Annunzio of Chieti-Pescara, 66100 Chieti, Italy; (L.M.); (R.A.)
| | - Giustino Orlando
- Department of Pharmacy, G. d’Annunzio University, 66013 Chieti, Italy; (C.F.); (G.O.)
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Kobayashi T, Uchino H, Elmér E, Ogihara Y, Fujita H, Sekine S, Ishida Y, Saiki I, Shibata S, Kawachi A. Disease Outcome and Brain Metabolomics of Cyclophilin-D Knockout Mice in Sepsis. Int J Mol Sci 2022; 23:961. [PMID: 35055146 PMCID: PMC8779771 DOI: 10.3390/ijms23020961] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2021] [Revised: 01/12/2022] [Accepted: 01/12/2022] [Indexed: 02/04/2023] Open
Abstract
Sepsis-associated encephalopathy (SAE) is a diffuse brain dysfunction resulting from a systemic inflammatory response to infection, but the mechanism remains unclear. The mitochondrial permeability transition pore (MPTP) could play a central role in the neuronal dysfunction, induction of apoptosis, and cell death in SAE. The mitochondrial isomerase cyclophilin D (CypD) is known to control the sensitivity of MPTP induction. We, therefore, established a cecal ligation and puncture (CLP) model, which is the gold standard in sepsis research, using CypD knockout (CypD KO) mice, and analyzed the disease phenotype and the possible molecular mechanism of SAE through metabolomic analyses of brain tissue. A comparison of adult, male wild-type, and CypD KO mice demonstrated statistically significant differences in body temperature, mortality, and histological changes. In the metabolomic analysis, the main finding was the maintenance of reduced glutathione (GSH) levels and the reduced glutathione/oxidized glutathione (GSH/GSSG) ratio in the KO animals following CLP. In conclusion, we demonstrate that CypD is implicated in the pathogenesis of SAE, possibly related to the inhibition of MPTP induction and, as a consequence, the decreased production of ROS and other free radicals, thereby protecting mitochondrial and cellular function.
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Affiliation(s)
- Takayuki Kobayashi
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Hiroyuki Uchino
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Eskil Elmér
- Mitochondrial Medicine, Department of Clinical Sciences, Lund University, 221 84 Lund, Sweden;
| | - Yukihiko Ogihara
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Hidetoshi Fujita
- Department of Biomedical Engineering, Osaka Institute of Technology, Osaka 535-8585, Japan;
| | - Shusuke Sekine
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Yusuke Ishida
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Iwao Saiki
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Shoichiro Shibata
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
| | - Aya Kawachi
- Department of Anesthesiology, Tokyo Medical University, Tokyo 160-0023, Japan; (H.U.); (Y.O.); (S.S.); (Y.I.); (I.S.); (S.S.); (A.K.)
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Neurovascular Impairment and Therapeutic Strategies in Diabetic Retinopathy. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 19:ijerph19010439. [PMID: 35010703 PMCID: PMC8744686 DOI: 10.3390/ijerph19010439] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2021] [Revised: 12/25/2021] [Accepted: 12/30/2021] [Indexed: 12/15/2022]
Abstract
Diabetic retinopathy has recently been defined as a highly specific neurovascular complication of diabetes. The chronic progression of the impairment of the interdependence of neurovascular units (NVUs) is associated with the pathogenesis of diabetic retinopathy. The NVUs consist of neurons, glial cells, and vascular cells, and the interdependent relationships between these cells are disturbed under diabetic conditions. Clinicians should understand and update the current knowledge of the neurovascular impairments in diabetic retinopathy. Above all, neuronal cell death is an irreversible change, and it is directly related to vision loss in patients with diabetic retinopathy. Thus, neuroprotective and vasoprotective therapies for diabetic retinopathy must be established. Understanding the physiological and pathological interdependence of the NVUs is helpful in establishing neuroprotective and vasoprotective therapies for diabetic retinopathy. This review focuses on the pathogenesis of the neurovascular impairments and introduces possible neurovascular protective therapies for diabetic retinopathy.
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The Pathogenesis and Therapeutic Approaches of Diabetic Neuropathy in the Retina. Int J Mol Sci 2021; 22:ijms22169050. [PMID: 34445756 PMCID: PMC8396448 DOI: 10.3390/ijms22169050] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 08/19/2021] [Accepted: 08/19/2021] [Indexed: 02/07/2023] Open
Abstract
Diabetic retinopathy is a major retinal disease and a leading cause of blindness in the world. Diabetic retinopathy is a neurovascular disease that is associated with disturbances of the interdependent relationship of cells composed of the neurovascular units, i.e., neurons, glial cells, and vascular cells. An impairment of these neurovascular units causes both neuronal and vascular abnormalities in diabetic retinopathy. More specifically, neuronal abnormalities including neuronal cell death and axon degeneration are irreversible changes that are directly related to the vision reduction in diabetic patients. Thus, establishment of neuroprotective and regenerative therapies for diabetic neuropathy in the retina is an emergent task for preventing the blindness of patients with diabetic retinopathy. This review focuses on the pathogenesis of the neuronal abnormalities in diabetic retina including glial abnormalities, neuronal cell death, and axon degeneration. The possible molecular cell death pathways and intrinsic survival and regenerative pathways are also described. In addition, therapeutic approaches for diabetic neuropathy in the retina both in vitro and in vivo are presented. This review should be helpful for providing clues to overcome the barriers for establishing neuroprotection and regeneration of diabetic neuropathy in the retina.
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Tang LHC, Fung FKC, Lai AKW, Wong IYH, Shih KC, Lo ACY. Autophagic Upregulation Is Cytoprotective in Ischemia/Reperfusion-Injured Retina and Retinal Progenitor Cells. Int J Mol Sci 2021; 22:8446. [PMID: 34445152 PMCID: PMC8395130 DOI: 10.3390/ijms22168446] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Revised: 08/02/2021] [Accepted: 08/03/2021] [Indexed: 11/16/2022] Open
Abstract
The cytoprotective versus cytotoxic role of macroautophagy in ocular ischemia/reperfusion injuries remains controversial and its effects under hyperglycemia are unclear. We investigated the involvement of autophagy in in vitro and in vivo normoglycemic and hyperglycemic models of retinal ischemia/reperfusion injury. Retinal ischemia (2 h) and reperfusion (2 or 22 h) was induced in wild-type and type I diabetic Ins2Akita/+ mice using a middle cerebral artery occlusion model. R28 retinal precursor cells were subjected to CoCl2-induced hypoxia with or without autophagic inhibitor NH4Cl. Autophagic regulation during ischemia/reperfusion was assessed through immunohistochemical detection and Western blotting of microtubule-associated protein 1A/1B-light chain 3 (LC3) and lysosomal associated membrane protein 1 (LAMP1). Effect of autophagic inhibition on cell viability and morphology under hypoxic conditions was also evaluated. Upregulation of autophagic markers in the inner retinae was seen after two hours reperfusion, with tapering of the response following 22 h of reperfusion in vivo. LC3-II turnover assays confirmed an increase in autophagic flux in our hypoxic in vitro model. Pharmacological autophagic inhibition under hypoxic conditions decreased cell survival and induced structural changes not demonstrated with autophagic inhibition alone. Yet no statistically significant different autophagic responses in ischemia/reperfusion injuries were seen between the two glycemic states.
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Affiliation(s)
| | | | | | | | | | - Amy Cheuk Yin Lo
- Department of Ophthalmology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong; (L.H.C.T.); (F.K.C.F.); (A.K.W.L.); (I.Y.H.W.); (K.C.S.)
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12
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Gromova OA, Torshin IY, Grishina TR, Demidov VI, Bogacheva TE. [Molecular and clinical aspects of the effect of cytidyndiphosphocholine on cognitive functions]. Zh Nevrol Psikhiatr Im S S Korsakova 2021; 121:88-97. [PMID: 34184483 DOI: 10.17116/jnevro202112105188] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE Systematization of the array of publications on cytidyldiphosphocholine (CDP-choline). MATERIAL AND METHODS Systematic computer analysis of all currently available publications on CDP-choline (1750 publications in PUBMED) using the topological theory of big data analysis. RESULTS CDP-choline is essential for acetylcholine biosynthesis, phospholipid metabolism, and DNA methylation. The article describes the effects of CDP-choline on acetylcholinergic and other types of neurotransmission, anti-inflammatory, neuroprotective and neurotrophic effects of CDP-choline. Also, the paper presents the effects of the molecule on lipid metabolism and gene expression within the post-genomic paradigm (in particular, an increase in the expression of nicotinic and muscarinic acetylcholine receptors). The results of fundamental and clinical studies of CDP-choline in the treatment of cognitive impairments associated with cerebral ischemia and neurodegeneration are presented. CONCLUSION The pharmacological effects of CDP-choline are mediated through multiple molecular mechanisms that contribute to the nootropic action of this molecule.
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Affiliation(s)
- O A Gromova
- Institute of Pharmacoinformatics of the Federal Research Center «Informatics and Control» RAS, Moscow, Russia.,Center for storing and analyzing big data of the National Center for Digital Economy of the Federal State Budgetary Educational Institution of Higher Education «Lomonosov Moscow State University», Moscow, Russia
| | - I Yu Torshin
- Institute of Pharmacoinformatics of the Federal Research Center «Informatics and Control» RAS, Moscow, Russia.,Center for storing and analyzing big data of the National Center for Digital Economy of the Federal State Budgetary Educational Institution of Higher Education «Lomonosov Moscow State University», Moscow, Russia
| | - T R Grishina
- Ivanovo State Medical Academy of the Ministry of Health of Russia, Ivanovo, Russia
| | - V I Demidov
- Ivanovo State Medical Academy of the Ministry of Health of Russia, Ivanovo, Russia
| | - T E Bogacheva
- Ivanovo State Medical Academy of the Ministry of Health of Russia, Ivanovo, Russia
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13
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Oshitari T. Understanding intrinsic survival and regenerative pathways through in vivo and in vitro studies: implications for optic nerve regeneration. EXPERT REVIEW OF OPHTHALMOLOGY 2021. [DOI: 10.1080/17469899.2021.1912595] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Japan
- Department of Ophthalmology, International University of Health and Welfare School of Medicine, Narita, Japan
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Oddone F, Rossetti L, Parravano M, Sbardella D, Coletta M, Ziccardi L, Roberti G, Carnevale C, Romano D, Manni G, Parisi V. Citicoline in Ophthalmological Neurodegenerative Disease: A Comprehensive Review. Pharmaceuticals (Basel) 2021; 14:281. [PMID: 33804675 PMCID: PMC8003774 DOI: 10.3390/ph14030281] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/17/2021] [Accepted: 03/18/2021] [Indexed: 12/12/2022] Open
Abstract
Cytidine 5'-diphosphocholine has been widely studied in systemic neurodegenerative diseases, like Alzheimer's disease, Parkinson's disease, and brain ischemia. The rationale for the use of citicoline in ophthalmological neurodegenerative diseases, including glaucoma, anterior ischemic optic neuropathy, and diabetic retinopathy, is founded on its multifactorial mechanism of action and the involvement in several metabolic pathways, including phospholipid homeostasis, mitochondrial dynamics, as well as cholinergic and dopaminergic transmission, all being involved in the complexity of the visual transmission. This narrative review is aimed at reporting both pre-clinical data regarding the involvement of citicoline in such metabolic pathways (including new insights about its role in the intracellular proteostasis through an interaction with the proteasome) and its effects on clinical psychophysical, electrophysiological, and morphological outcomes following its use in ophthalmological neurodegenerative diseases (including the results of the most recent prospective randomized clinical trials).
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Affiliation(s)
- Francesco Oddone
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Luca Rossetti
- Eye Clinic, ASST Santi Paolo e Carlo, San Paolo Hospital, University of Milan, Via Antonio di Rudinì, 8, 20142 Milan, Italy; (L.R.); (D.R.)
| | - Mariacristina Parravano
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Diego Sbardella
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Viale Oxford 81, 00133 Rome, Italy; (M.C.); (G.M.)
| | - Lucia Ziccardi
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Gloria Roberti
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Carmela Carnevale
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
| | - Dario Romano
- Eye Clinic, ASST Santi Paolo e Carlo, San Paolo Hospital, University of Milan, Via Antonio di Rudinì, 8, 20142 Milan, Italy; (L.R.); (D.R.)
| | - Gianluca Manni
- Department of Clinical Sciences and Translational Medicine, University of Rome Tor Vergata, Viale Oxford 81, 00133 Rome, Italy; (M.C.); (G.M.)
| | - Vincenzo Parisi
- IRCCS-Fondazione Bietti, Via Livenza, 3, 00198 Rome, Italy; (F.O.); (D.S.); (L.Z.); (G.R.); (C.C.); (V.P.)
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15
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Fudalej E, Justyniarska M, Kasarełło K, Dziedziak J, Szaflik JP, Cudnoch-Jędrzejewska A. Neuroprotective Factors of the Retina and Their Role in Promoting Survival of Retinal Ganglion Cells: A Review. Ophthalmic Res 2021; 64:345-355. [PMID: 33454713 DOI: 10.1159/000514441] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2020] [Accepted: 01/09/2021] [Indexed: 11/19/2022]
Abstract
Retinal ganglion cells (RGCs) play a crucial role in the visual pathway. As their axons form the optic nerve, apoptosis of these cells causes neurodegenerative vision loss. RGC death could be triggered by increased intraocular pressure, advanced glycation end products, or mitochondrial dysfunction. In this review, we summarize the role of some neuroprotective factors in RGC injury: ciliary neurotrophic factor (CNTF), nerve growth factor (NGF), brain-derived neurotrophic factor, vascular endothelial growth factor, pigment epithelium-derived factor, glial cell line-derived neurotrophic factor, and Norrin. Each, in their own unique way, prevents RGC damage caused by glaucoma, ocular hypertension, ischemic neuropathy, and even oxygen-induced retinopathy. These factors are produced mainly by neurons, leukocytes, glial cells, and epithelial cells. Neuroprotective factors act via various signaling pathways, including JAK/STAT, MAPK, TrkA, and TrkB, which promotes RGC survival. Many attempts have been made to develop therapeutic strategies using these factors. There are ongoing clinical trials with CNTF and NGF, but they have not yet been accepted for clinical use.
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Affiliation(s)
- Ewa Fudalej
- Department of Experimental and Clinical Physiology, Center for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Magdalena Justyniarska
- Department of Experimental and Clinical Physiology, Center for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
| | - Kaja Kasarełło
- Department of Experimental and Clinical Physiology, Center for Preclinical Research, Medical University of Warsaw, Warsaw, Poland,
| | - Jacek Dziedziak
- Department of Experimental and Clinical Physiology, Center for Preclinical Research, Medical University of Warsaw, Warsaw, Poland.,Department of Ophthalmology, SPKSO Ophthalmic University Hospital, Medical University of Warsaw, Warsaw, Poland
| | - Jacek P Szaflik
- Department of Ophthalmology, SPKSO Ophthalmic University Hospital, Medical University of Warsaw, Warsaw, Poland
| | - Agnieszka Cudnoch-Jędrzejewska
- Department of Experimental and Clinical Physiology, Center for Preclinical Research, Medical University of Warsaw, Warsaw, Poland
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16
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Current Medical Therapy and Future Trends in the Management of Glaucoma Treatment. J Ophthalmol 2020; 2020:6138132. [PMID: 32774906 PMCID: PMC7391108 DOI: 10.1155/2020/6138132] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Accepted: 06/29/2020] [Indexed: 01/02/2023] Open
Abstract
Glaucoma is a neurodegenerative disease characterized by progressive loss of retinal ganglion cells and their axons. Lowering of intraocular pressure (IOP) is currently the only proven treatment strategy for glaucoma. However, some patients show progressive loss of visual field and quality of life despite controlled IOP which indicates that other factors are implicated in glaucoma. Therefore, approaches that could prevent or decrease the rate of progression and do not rely on IOP lowering have gained much attention. Effective neuroprotection has been reported in animal models of glaucoma, but till now, no neuroprotective agents have been clinically approved. The present update provides an overview of currently available IOP-lowering medications. Moreover, potential new treatment targets for IOP-lowering and neuroprotective therapy are discussed. Finally, future trends in glaucoma therapy are addressed, including sustained drug delivery systems and progress toward personalized medicine.
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17
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Effect of neuroprotective citicoline eye drops on macular microcirculation. Int Ophthalmol 2020; 40:2237-2246. [PMID: 32388671 DOI: 10.1007/s10792-020-01404-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Accepted: 04/27/2020] [Indexed: 10/24/2022]
Abstract
BACKGROUND AND OBJECTIVE To use optical coherence tomography (OCTA) examination of the retinal microvascular structures to evaluate the effect of neuroprotective eye drops (citicoline, OMK1®) administered for laser in situ keratomileusis (LASIK) surgery. PATIENTS AND METHODS This prospective study included 45 patients treated with citicoline after LASIK and 48 patients not treated with citicoline after LASIK as a control group. In both groups, the foveal avascular zone (FAZ), retinal superficial vascular density (SVD), and deep vascular density (DVD) in the foveal and parafoveal areas were measured preoperatively and at 1 and 3 months postoperatively using OCTA. RESULTS No significant difference was detected between the groups in terms of preoperative SVD or DVD in the foveal and parafoveal zones and all quadrants (superior, inferior, temporal, and nasal) (P > 0.05). Similarly, no significant difference was detected between the citicoline group and control group in terms of SVD or DVD in the foveal and parafoveal zones at 1 and 3 months after LASIK (P > 0.05). CONCLUSIONS Despite their neuroprotective effect, topical citicoline drops had no significant effect on the superficial and deep microvascular structures of the retina or choriocapillaris.
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18
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Sbardella D, Coletta A, Tundo GR, Ahmed IMM, Bellia F, Oddone F, Manni G, Coletta M. Structural and functional evidence for citicoline binding and modulation of 20S proteasome activity: Novel insights into its pro-proteostatic effect. Biochem Pharmacol 2020; 177:113977. [PMID: 32298691 DOI: 10.1016/j.bcp.2020.113977] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2020] [Accepted: 04/10/2020] [Indexed: 02/01/2023]
Abstract
Citicoline or CDP-choline is a drug, made up by a cytidine 5'-diphosphate moiety and choline, which upon adsorption is rapidly hydrolyzed into cytidine 5'-diphosphate and choline, easily bypassing the blood-brain barrier. Once in the brain, these metabolites are used to re-synthesize citicoline in neurons and in the other cell histo-types which uptake them. Citicoline administration finds broad therapeutic application in the treatment of glaucoma as well as other retinal disorders by virtue of its safety profile and neuro-protective and neuroenhancer activity, which significantly improves the visual function. Further, though supported by limited clinical studies, this molecule finds therapeutic application in neurodegenerative disease, delaying the cognitive decline in Alzheimer's Disease (AD) and Parkinson's Disease (PD) subjects. In this work we show that citicoline greatly affects the proteolytic activity of the 20S proteasome on synthetic and natural substrates, functioning as a bimodal allosteric modulator, likely binding at multiple sites. In silico binding simulations identify several potential binding sites for citicoline on 20S proteasome, and their topology envisages the possibility that, by occupying some of these pockets, citicoline may induce a conformational shift of the 20S proteasome, allowing to sketch a working hypothesis for the structural basis of its function as allosteric modulator. In addition, we show that over the same concentration range citicoline affects the distribution of assembled proteasome populations and turn-over of ubiquitinated proteins in SH-SY5Y and SK-N-BE human neuroblastoma cells, suggesting its potential role as a regulator of proteostasis in nervous cells.
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Affiliation(s)
- Diego Sbardella
- IRCCS-Fondazione G.B. BIETTI, via Livenza, 3, 00189, Rome, Italy.
| | - Andrea Coletta
- Department of Chemistry, Aarhus University, Aarhus, Denmark
| | - Grazia Raffaella Tundo
- Department of Clinical Sciences and Translational Medicine, University of Roma Tor Vergata, via Montpellier, 1, 00133, Rome, Italy
| | - Ikhlas M M Ahmed
- Institute of Crystallography, CNR, via Gaifami, 18, 95126, Catania, Italy
| | - Francesco Bellia
- Institute of Crystallography, CNR, via Gaifami, 18, 95126, Catania, Italy
| | - Francesco Oddone
- IRCCS-Fondazione G.B. BIETTI, via Livenza, 3, 00189, Rome, Italy
| | - Gianluca Manni
- Department of Clinical Sciences and Translational Medicine, University of Roma Tor Vergata, via Montpellier, 1, 00133, Rome, Italy
| | - Massimo Coletta
- Department of Clinical Sciences and Translational Medicine, University of Roma Tor Vergata, via Montpellier, 1, 00133, Rome, Italy.
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19
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Mesentier-Louro LA, Shariati MA, Dalal R, Camargo A, Kumar V, Shamskhou EA, de Jesus Perez V, Liao YJ. Systemic hypoxia led to little retinal neuronal loss and dramatic optic nerve glial response. Exp Eye Res 2020; 193:107957. [PMID: 32032627 PMCID: PMC7673281 DOI: 10.1016/j.exer.2020.107957] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Revised: 12/19/2019] [Accepted: 02/03/2020] [Indexed: 01/23/2023]
Abstract
Vision loss is a devastating consequence of systemic hypoxia, but the cellular mechanisms are unclear. We investigated the impact of acute hypoxia in the retina and optic nerve. We induced systemic hypoxia (10% O2) in 6-8w mice for 48 h and performed in vivo imaging using optical coherence tomography (OCT) at baseline and after 48 h to analyze structural changes in the retina and optic nerve. We analyzed glial cellular and molecular changes by histology and immunofluorescence and the impact of pretreatment with 4-phenylbutyric acid (4-PBA) in oligodendroglia survival. After 48 h hypoxia, we found no change in ganglion cell complex thickness and no loss of retinal ganglion cells. Despite this, there was significantly increased expression of CCAAT-enhancer-binding protein homologous protein (CHOP), a marker of endoplasmic reticulum stress, in the retina and optic nerve. In addition, hypoxia induced obvious increase of GFAP expression in the anterior optic nerve, where it co-localized with CHOP, and significant loss of Olig2+ oligodendrocytes. Pretreatment with 4-PBA, which has been shown to reduce endoplasmic reticulum stress, rescued total Olig2+ oligodendrocytes and increased the pool of mature (CC-1+) but not of immature (PDGFRa+) oligodendrocytes. Consistent with a selective vulnerability of the retina and optic nerve in hypoxia, the most striking changes in the 48 h murine model of hypoxia were in glial cells in the optic nerve, including increased CHOP expression in the astrocytes and loss of oligodendrocytes. Our data support a model where glial dysfunction is among the earliest events in systemic hypoxia - suggesting that glia may be a novel target in treatment of hypoxia.
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Affiliation(s)
| | - Mohammed Ali Shariati
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Roopa Dalal
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Alexandra Camargo
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Varun Kumar
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, CA, USA
| | - Elya Ali Shamskhou
- Department of Pulmonary Medicine, Stanford University, School of Medicine, Stanford, CA, USA
| | - Vinicio de Jesus Perez
- Department of Pulmonary Medicine, Stanford University, School of Medicine, Stanford, CA, USA
| | - Yaping Joyce Liao
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, CA, USA; Department of Neurology, Stanford University, School of Medicine, Stanford, CA, USA.
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20
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Calbiague VM, Vielma AH, Cadiz B, Paquet‐Durand F, Schmachtenberg O. Physiological assessment of high glucose neurotoxicity in mouse and rat retinal explants. J Comp Neurol 2019; 528:989-1002. [DOI: 10.1002/cne.24805] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2019] [Revised: 09/09/2019] [Accepted: 10/20/2019] [Indexed: 12/31/2022]
Affiliation(s)
- Víctor M. Calbiague
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Facultad de Ciencias Universidad de Valparaíso Valparaíso Chile
- Programa Doctorado en Ciencias, mención Neurociencias Universidad de Valparaíso Valparaíso Chile
| | - Alex H. Vielma
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Facultad de Ciencias Universidad de Valparaíso Valparaíso Chile
| | - Bárbara Cadiz
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Facultad de Ciencias Universidad de Valparaíso Valparaíso Chile
| | - Francois Paquet‐Durand
- Cell Death Mechanism Group Institute for Ophthalmic Research, University of Tübingen Tübingen Germany
| | - Oliver Schmachtenberg
- Centro Interdisciplinario de Neurociencia de Valparaíso (CINV), Facultad de Ciencias Universidad de Valparaíso Valparaíso Chile
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21
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Kumar V, Mesentier-Louro LA, Oh AJ, Heng K, Shariati MA, Huang H, Hu Y, Liao YJ. Increased ER Stress After Experimental Ischemic Optic Neuropathy and Improved RGC and Oligodendrocyte Survival After Treatment With Chemical Chaperon. Invest Ophthalmol Vis Sci 2019; 60:1953-1966. [PMID: 31060051 PMCID: PMC6735778 DOI: 10.1167/iovs.18-24890] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Purpose Increased endoplasmic reticulum (ER) stress is one of the earliest subcellular changes in neuro-ophthalmic diseases. In this study, we investigated the expression of key molecules in the ER stress pathways following nonarteritic anterior ischemic optic neuropathy (AION), the most common acute optic neuropathy in adults over 50, and assessed the impact of chemical chaperon 4-phenylbutyric acid (4-PBA) in vivo. Methods We induced AION using photochemical thrombosis in adult mice and performed histologic analyses of key molecules in the ER stress pathway in the retina and optic nerve. We also assessed the effects of daily intraperitoneal injections of 4-PBA after AION. Results In the retina at baseline, there was low proapoptotic transcriptional regulator C/EBP homologous protein (CHOP) and high prosurvival chaperon glucose-regulated protein 78 (GRP78) expression in retinal ganglion cells (RGCs). One day after AION, there was significantly increased CHOP and reduced GRP78 expressions in the ganglion cell layer. In the optic nerve at baseline, there was little CHOP and high GRP78 expression. One day after AION, there was significantly increased CHOP and no change in GRP78 expression. Treatment immediately after AION using daily intraperitoneal injection of chemical chaperone 4-PBA for 19 days significantly rescued Brn3A+ RGCs and Olig2+ optic nerve oligodendrocytes. Conclusions We showed for the first time that acute AION resulted in increased ER stress and differential expression of ER stress markers CHOP and GRP78 in the retina and optic nerve. Rescue of RGCs and oligodendrocytes with 4-PBA provides support for ER stress reduction as possible treatment for AION.
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Affiliation(s)
- Varun Kumar
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | | | - Angela Jinsook Oh
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | - Kathleen Heng
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | - Mohammad Ali Shariati
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | - Haoliang Huang
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | - Yang Hu
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States
| | - Yaping Joyce Liao
- Department of Ophthalmology, Stanford University, School of Medicine, Stanford, California, United States.,Department of Neurology, Stanford University, School of Medicine, Stanford, California, United States
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22
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Parisi V, Barbano L, Di Renzo A, Coppola G, Ziccardi L. Neuroenhancement and neuroprotection by oral solution citicoline in non-arteritic ischemic optic neuropathy as a model of neurodegeneration: A randomized pilot study. PLoS One 2019; 14:e0220435. [PMID: 31348806 PMCID: PMC6660126 DOI: 10.1371/journal.pone.0220435] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Accepted: 07/05/2019] [Indexed: 12/02/2022] Open
Abstract
PURPOSE To evaluate whether treatment with Citicoline in oral solution (OS-Citicoline) would increase visual function, retinal ganglion cells (RGCs) function, and neural conduction along visual pathways (neuroenhancement), and/or induce preservation of RGCs fibers' loss (neuroprotection) in non-arteritic ischemic optic neuropathy (NAION), a human model of neurodegeneration. METHODS Thirty-six patients with NAION and 20 age-matched controls were enrolled. Nineteen NAION patients received 500 mg/day of OS-Citicoline for a 6-month period followed by 3-month of wash-out (NC Group); 17 NAION patients were not treated (NN Group) from baseline to 9 months. In all subjects at baseline, and in NC and NN eyes at 6 and 9 months of follow-up, we assessed Visual Acuity (VA), Pattern Electroretinogram (PERG), Visual Evoked Potentials (VEP), retinal nerve fiber layer thickness (RNFL-T), and Humphrey 24-2 visual field mean deviation (HFA MD). Mean differences were statistically evaluated with ANOVA between Groups, and linear correlations were analysed with Pearson's test. RESULTS At 6 months, significant differences between groups for all parameters were observed (ANOVA, p<0.01). In NC eyes, VA increased, PERG responses increased, VEP recordings improved and were significantly correlated with increases in HFA MD (p<0.01), and RNFL-T was unmodified or improved. In contrast, in NN eyes, VA, PERG, VEP responses, RNFL-T, and HFA MD were further worsened. Significant differences were still present at 9-month follow-up in the NN Group and after 3 months of OS-Citicoline wash-out in NC eyes. CONCLUSIONS OS-Citicoline treatment induced neuroenhancement (improvement in RGCs function and neural conduction along visual pathways related to improvement of visual field defects) and neuroprotection (unmodified or improved RNFL morphological condition) in a human model of NAION involving fast RGCs degeneration. TRIAL REGISTRATION ClinicalTrials.gov NCT03758118.
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Affiliation(s)
| | | | | | - Gianluca Coppola
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome—Polo Pontino, Latina, Italy
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23
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Parisi V, Oddone F, Ziccardi L, Roberti G, Coppola G, Manni G. Citicoline and Retinal Ganglion Cells: Effects on Morphology and Function. Curr Neuropharmacol 2018; 16:919-932. [PMID: 28676014 PMCID: PMC6120106 DOI: 10.2174/1570159x15666170703111729] [Citation(s) in RCA: 39] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2017] [Revised: 06/07/2017] [Accepted: 06/22/2017] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Retinal ganglion cells (RGCs) are the nervous retinal elements which connect the visual receptors to the brain forming the nervous visual system. Functional and/or morphological involvement of RGCs occurs in several ocular and neurological disorders and therefore these cells are targeted in neuroprotective strategies. Cytidine 5-diphosphocholine or Citicoline is an endogenous compound that acts in the biosynthesis of phospholipids of cell membranes and increases neurotransmitters' levels in the Central Nervous System. Experimental studies suggested the neuromodulator effect and the protective role of Citicoline on RGCs. This review aims to present evidence of the effects of Citicoline in experimental models of RGCs degeneration and in human neurodegenerative disorders involving RGCs. METHODS All published papers containing experimental or clinical studies about the effects of Citicoline on RGCs morphology and function were reviewed. RESULTS In rodent retinal cultures and animal models, Citicoline induces antiapoptotic effects, increases the dopamine retinal level, and counteracts retinal nerve fibers layer thinning. Human studies in neurodegenerative visual pathologies such as glaucoma or non-arteritic ischemic neuropathy showed a reduction of the RGCs impairment after Citicoline administration. By reducing the RGCs' dysfunction, a better neural conduction along the post-retinal visual pathways with an improvement of the visual field defects was observed. CONCLUSION Citicoline, with a solid history of experimental and clinical studies, could be considered a very promising molecule for neuroprotective strategies in those pathologies (i.e. Glaucoma) in which morpho-functional changes of RGCc occurs.
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Affiliation(s)
- Vincenzo Parisi
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy
| | | | - Lucia Ziccardi
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy
| | - Gloria Roberti
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy
| | | | - Gianluca Manni
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy.,DSCMT, Università di Roma Tor Vergata, Viale Oxford 81, 00133 Rome, Italy
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24
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Chakravarthy H, Devanathan V. Molecular Mechanisms Mediating Diabetic Retinal Neurodegeneration: Potential Research Avenues and Therapeutic Targets. J Mol Neurosci 2018; 66:445-461. [PMID: 30293228 DOI: 10.1007/s12031-018-1188-x] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/25/2018] [Indexed: 12/16/2022]
Abstract
Diabetic retinopathy (DR) is a devastating complication of diabetes with a prevalence rate of 35%, and no effective treatment options. Since the most visible clinical features of DR are microvascular irregularities, therapeutic interventions often attempt to reduce microvascular injury, but only after permanent retinal damage has ensued. However, recent data suggests that diabetes initially affects retinal neurons, leading to neurodegeneration as an early occurrence in DR, before onset of the more noticeable vascular abnormalities. In this review, we delineate the sequence of initiating events leading to retinal degeneration in DR, considering neuronal dysfunction as a primary event. Key molecular mechanisms and potential biomarkers associated with retinal neuronal degeneration in diabetes are discussed. In addition to glial reactivity and inflammation in the diabetic retina, the contribution of neurotrophic factors, cell adhesion molecules, apoptosis markers, and G protein signaling to neurodegenerative pathways warrants further investigation. These studies could complement recent developments in innovative treatment strategies for diabetic retinopathy, such as targeting retinal neuroprotection, promoting neuronal regeneration, and attempts to re-program other retinal cell types into functional neurons. Indeed, several ongoing clinical trials are currently attempting treatment of retinal neurodegeneration by means of such novel therapeutic avenues. The aim of this article is to highlight the crucial role of neurodegeneration in early retinopathy progression, and to review the molecular basis of neuronal dysfunction as a first step toward developing early therapeutic interventions that can prevent permanent retinal damage in diabetes. ClinicalTrials.gov: NCT02471651, NCT01492400.
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Affiliation(s)
- Harshini Chakravarthy
- Department of Biology, Indian Institute of Science Education and Research (IISER), Transit campus: C/o. Sree Rama Engineering College Campus, Karakambadi Road, Mangalam, Tirupati, 517507, India
| | - Vasudharani Devanathan
- Department of Biology, Indian Institute of Science Education and Research (IISER), Transit campus: C/o. Sree Rama Engineering College Campus, Karakambadi Road, Mangalam, Tirupati, 517507, India.
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25
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Antonio ML, Laura R, Annagrazia A, Tiziana CM, Rossella R. Rational Basis for Nutraceuticals in the Treatment of Glaucoma. Curr Neuropharmacol 2018; 16:1004-1017. [PMID: 29119928 PMCID: PMC6120110 DOI: 10.2174/1570159x15666171109124520] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Glaucoma, the second leading cause of blindness worldwide, is a chronic optic neuropathy characterized by progressive retinal ganglion cell (RGC) axons degeneration and death. Primary open-angle glaucoma (OAG), the most common type, is often associated with increased intraocular pressure (IOP), however other factors have been recognized to partecipate to the patogenesis of the optic neuropathy. IOP-independent mechanisms that contribute to the glaucoma-related neurodegeneration include oxidative stress, excitotoxicity, neuroinflammation, and impaired ocular blood flow. The involvement of several and diverse factors is one of the reasons for the progression of glaucoma observed even under efficient IOP control with the currently available drugs. METHODS Current research and online content related to the potential of nutritional supplements for limiting retinal damage and improving RGC survival is reviewed. RESULTS Recent studies have suggested a link between dietary factors and glaucoma risk. Particularly, some nutrients have proven capable of lowering IOP, increase circulation to the optic nerve, modulate excitotoxicity and promote RGC survival. However, the lack of clinical trials limit their current therapeutic use. The appropriate use of nutraceuticals that may be able to modify the risk of glaucoma may provide insight into glaucoma pathogenesis and decrease the need for, and therefore the side effects from, conventional therapies. CONCLUSION The effects of nutrients with anti-oxidant and neuroprotective properties are of great interest and nutraceuticals may offer some therapeutic potential although a further rigorous evaluation of nutraceuticals in the treatment of glaucoma is needed to determine their safety and efficacy.
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Affiliation(s)
- Morrone Luigi Antonio
- Address correspondence to this author at the Department of Pharmacy, Health and Nutritional Sciences, Section of Preclinical and Translational Pharmacology, University of Calabria, via P. Bucci, 87036 Rende (CS) Italy; E-mail:
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Bucolo C, Platania CBM, Drago F, Bonfiglio V, Reibaldi M, Avitabile T, Uva M. Novel Therapeutics in Glaucoma Management. Curr Neuropharmacol 2018; 16:978-992. [PMID: 28925883 PMCID: PMC6120119 DOI: 10.2174/1570159x15666170915142727] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 06/26/2017] [Accepted: 09/03/2017] [Indexed: 11/22/2022] Open
Abstract
BACKGROUND Glaucoma is a progressive optic neuropathy characterized by retinal ganglion cell death and alterations of visual field. Elevated intraocular pressure (IOP) is considered the main risk factor of glaucoma, even though other factors cannot be ruled out, such as epigenetic mechanisms. OBJECTIVE An overview of the ultimate promising experimental drugs to manage glaucoma has been provided. RESULTS In particular, we have focused on purinergic ligands, KATP channel activators, gases (nitric oxide, carbon monoxide and hydrogen sulfide), non-glucocorticoid steroidal compounds, neurotrophic factors, PI3K/Akt activators, citicoline, histone deacetylase inhibitors, cannabinoids, dopamine and serotonin receptors ligands, small interference RNA, and Rho kinase inhibitors. CONCLUSIONS The review has been also endowed of a brief chapter on last reports about potential neuroprotective benefits of anti-glaucoma drugs already present in the market.
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Affiliation(s)
- Claudio Bucolo
- Address correspondence to this author at the Department of Biomedical and Biotechnological Sciences, School of Medicine, University of Catania, Via S. Sofia 97, 95123 Catania, Italy; Tel: +39 095 4781196;
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Davinelli S, Chiosi F, Di Marco R, Costagliola C, Scapagnini G. Cytoprotective Effects of Citicoline and Homotaurine against Glutamate and High Glucose Neurotoxicity in Primary Cultured Retinal Cells. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2017; 2017:2825703. [PMID: 29163753 PMCID: PMC5661090 DOI: 10.1155/2017/2825703] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Accepted: 09/27/2017] [Indexed: 02/06/2023]
Abstract
Citicoline and homotaurine are renowned compounds that exhibit potent neuroprotective activities through distinct molecular mechanisms. The present study was undertaken to demonstrate whether cotreatment with citicoline and homotaurine affects cell survival in primary retinal cultures under experimental conditions simulating retinal neurodegeneration. Primary cultures were obtained from the retina of fetal rats and exposed to citicoline plus homotaurine (100 μM). Subsequently, neurotoxicity was induced using excitotoxic levels of glutamate and high glucose concentrations. The effects on retinal cultures were assessed by cell viability and immunodetection of apoptotic oligonucleosomes. The results showed that a combination of citicoline and homotaurine synergistically decreases proapoptotic effects associated with glutamate- and high glucose-treated retinal cultures. This study provides an insight into the potential application of citicoline and homotaurine as a valuable tool to exert neuroprotective effects against retinal damage.
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Affiliation(s)
- Sergio Davinelli
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
| | - Flavia Chiosi
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
| | - Roberto Di Marco
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
| | - Ciro Costagliola
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
| | - Giovanni Scapagnini
- Department of Medicine and Health Sciences “V. Tiberio”, University of Molise, Campobasso, Italy
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Wang Y, Zhou Y, Xiao L, Zheng S, Yan N, Chen D. E2f1 mediates high glucose-induced neuronal death in cultured mouse retinal explants. Cell Cycle 2017; 16:1824-1834. [PMID: 28825879 DOI: 10.1080/15384101.2017.1361070] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Diabetic retinopathy (DR) is the most common complication of diabetes and remains one of the major causes of blindness in the world; infants born to diabetic mothers have higher risk of developing retinopathy of prematurity (ROP). While hyperglycemia is a major risk factor, the molecular and cellular mechanisms underlying DR and diabetic ROP are poorly understood. To explore the consequences of retinal cells under high glucose, we cultured wild type or E2f1-/- mouse retinal explants from postnatal day 8 with normal glucose, high osmotic or high glucose media. Explants were also incubated with cobalt chloride (CoCl2) to mimic the hypoxic condition. We showed that, at 7 days post exposure to high glucose, retinal explants displayed elevated cell death, ectopic cell division and intact retinal vascular plexus. Cell death mainly occurred in excitatory neurons, such as ganglion and bipolar cells, which were also ectopically dividing. Many Müller glial cells reentered the cell cycle; some had irregular morphology or migrated to other layers. High glucose inhibited the hyperoxia-induced blood vessel regression of retinal explants. Moreover, inactivation of E2f1 rescued high glucose-induced ectopic division and cell death of retinal neurons, but not ectopic cell division of Müller glial cells and vascular phenotypes. This suggests that high glucose has direct but distinct effects on retinal neurons, glial cells and blood vessels, and that E2f1 mediates its effects on retinal neurons. These findings shed new light onto mechanisms of DR and the fetal retinal abnormalities associated with maternal diabetes, and suggest possible new therapeutic strategies.
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Affiliation(s)
- Yujiao Wang
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
| | - Yi Zhou
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
| | - Lirong Xiao
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
| | - Shijie Zheng
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
| | - Naihong Yan
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
| | - Danian Chen
- a Department of Ophthalmology, Research Laboratory of Ophthalmology and Vision Sciences , Torsten-Wiesel Research Institute of World Eye Organization, State Key Laboratory of Biotherapy, West China Hospital, Sichuan University , Chengdu , China
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Thomas CN, Berry M, Logan A, Blanch RJ, Ahmed Z. Caspases in retinal ganglion cell death and axon regeneration. Cell Death Discov 2017; 3:17032. [PMID: 29675270 PMCID: PMC5903394 DOI: 10.1038/cddiscovery.2017.32] [Citation(s) in RCA: 57] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Revised: 03/31/2017] [Accepted: 04/23/2017] [Indexed: 02/07/2023] Open
Abstract
Retinal ganglion cells (RGC) are terminally differentiated CNS neurons that possess limited endogenous regenerative capacity after injury and thus RGC death causes permanent visual loss. RGC die by caspase-dependent mechanisms, including apoptosis, during development, after ocular injury and in progressive degenerative diseases of the eye and optic nerve, such as glaucoma, anterior ischemic optic neuropathy, diabetic retinopathy and multiple sclerosis. Inhibition of caspases through genetic or pharmacological approaches can arrest the apoptotic cascade and protect a proportion of RGC. Novel findings have also highlighted a pyroptotic role of inflammatory caspases in RGC death. In this review, we discuss the molecular signalling mechanisms of apoptotic and inflammatory caspase responses in RGC specifically, their involvement in RGC degeneration and explore their potential as therapeutic targets.
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Affiliation(s)
- Chloe N Thomas
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Martin Berry
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Ann Logan
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
| | - Richard J Blanch
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK.,Academic Department of Military Surgery and Trauma, Royal Centre for Defence Medicine, Birmingham, UK
| | - Zubair Ahmed
- Neuroscience and Ophthalmology, Institute of Inflammation and Ageing, University of Birmingham, Birmingham, UK
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Combination of Neuroprotective and Regenerative Agents for AGE-Induced Retinal Degeneration: In Vitro Study. BIOMED RESEARCH INTERNATIONAL 2017; 2017:8604723. [PMID: 28573143 PMCID: PMC5440790 DOI: 10.1155/2017/8604723] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Revised: 02/27/2017] [Accepted: 04/04/2017] [Indexed: 11/18/2022]
Abstract
To determine the most effective combination of neuroprotective and regenerative agents for cultured retinal neurons from advanced glycation end products- (AGEs-) induced degeneration, retinal explants of 7 adult Sprague-Dawley rats were three-dimensionally cultured in collagen gel and incubated in serum-free media and in 7 media; namely, AGEs, AGEs + 100 μM citicoline, AGEs + 10 ng/mL NT-4, AGEs + 100 μM TUDCA, AGEs + 100 μM citicoline + TUDCA (doublet), and AGEs + 100 μM citicoline + TUDCA + 10 ng/mL NT-4 (triplet) were examined. The number of regenerating neurites was counted after 7 days of culture, followed by performing TUNEL and DAPI staining. The ratio of TUNEL-positive cells to the number of DAPI-stained nuclei was calculated. Immunohistochemical examinations for the active form of caspase-9 and JNK were performed. All of the neuroprotectants increased the number of neurites and decreased the number of TUNEL-positive cells. However, the number of neurites was significantly higher, and the number of TUNEL-positive cells and caspase-9- and JNK-immunopositive cells was fewer in the retinas incubated with the combined three agents. Combination solutions containing citicoline, TUDCA, and NT-4 should be considered for neuroprotective and regenerative therapy for AGE-related retinal degeneration.
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Mesenchymal stem cells attenuate hydrogen peroxide-induced oxidative stress and enhance neuroprotective effects in retinal ganglion cells. In Vitro Cell Dev Biol Anim 2016; 53:328-335. [PMID: 27864663 DOI: 10.1007/s11626-016-0115-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2016] [Accepted: 11/01/2016] [Indexed: 12/14/2022]
Abstract
The apoptosis of retinal ganglion cells leads to visual impairment and blindness in ocular neurodegenerative diseases, especially in diabetic retinopathy (DR). Mounting evidence suggests that oxidative stress contributes to the pathogenesis of DR. In the present study, we investigated whether bone mesenchymal stem cells (BMSCs) have protective ability to relieve hydrogen peroxide (H2O2)-induced injury on retinal ganglion cells in vitro. An immortalized retinal ganglion cells, RGC-5 cells, were exposed to an indicated concentration of H2O2 for 24 h. Cell viability was analyzed by CCK-8 assay to find out a certain concentration to build H2O2 oxidative damage model. Morphological changes in RGC-5 cells were observed under optical microscope, and cell apoptosis was detected with Hoechst fluorescence staining. Then, BMSCs were co-cultured with RGC-5 cells in a transwell culture system for 24 h and 48 h. Flow cytometry was performed to qualify the apoptosis rate of RGC-5 cells. Conditioned medium was collected for evaluation the inflammatory cytokines by ELISA. The content of intracellular malondialdehyde (MDA) and superoxide dismutase (SOD) was assayed by thiobarbituric acid and xanthine oxidase method, respectively. qRT-PCR and ELISA were conducted for analysis of the expression changes in brain-derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF), respectively. After H2O2 exposure, the morphological varieties were observed as cytoplasm shrinking and paramorphia together with nuclear gathering. Meanwhile, the apoptotic cells had hyperfluorescence with Hoechst 33258 staining. Co-culture with BMSCs significantly inhibited retinal cell death. It was found that BMSCs reduced H2O2-induced inflammatory factors IL-1β and TNF-α, down-regulated intracellular oxidant factor MDA, up-regulated intracellular antioxidant factor SOD, and increased neurotrophins BDNF and CNTF expression. BMSCs may enhance protective effect of RGC-5 cells in H2O2-induced damage through improving antioxidant capacity, inhibiting pro-inflammatory cytokine secretion, and promoting neurotrophin expression.
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Grieb P, Jünemann A, Rekas M, Rejdak R. Citicoline: A Food Beneficial for Patients Suffering from or Threated with Glaucoma. Front Aging Neurosci 2016; 8:73. [PMID: 27092075 PMCID: PMC4824764 DOI: 10.3389/fnagi.2016.00073] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 03/28/2016] [Indexed: 12/13/2022] Open
Abstract
Oral form of citicoline, a nootropic and neuroprotective drug in use for almost five decades, recently was pronounced a food supplement in both USA and EU. The idea of adding citicoline to topical treatment of primary open angle glaucoma (POAG) aimed at decreasing intraocular pressure (IOP) appeared as a logical consequence of accepting neurodegenerative character of this disease. Experimental data, and also few clinical studies indicate that this substance has potential to counteract some important pathological mechanisms which seem to contribute to POAG initiation and progression, such as excitotoxicity and oxidative stress.
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Affiliation(s)
- Pawel Grieb
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of Sciences Warsaw, Poland
| | - Anselm Jünemann
- Department of Ophthalmology, University of Rostock Rostock, Germany
| | - Marek Rekas
- Department of Ophthalmology, Military Institute of Medicine Warsaw, Poland
| | - Robert Rejdak
- Department of Experimental Pharmacology, Mossakowski Medical Research Centre, Polish Academy of SciencesWarsaw, Poland; Department of General Ophthalmology, Medical University of LublinLublin, Poland
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Ocular Complications of Diabetes and Therapeutic Approaches. BIOMED RESEARCH INTERNATIONAL 2016; 2016:3801570. [PMID: 27119078 PMCID: PMC4826913 DOI: 10.1155/2016/3801570] [Citation(s) in RCA: 89] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 02/03/2016] [Accepted: 03/02/2016] [Indexed: 12/15/2022]
Abstract
Diabetes mellitus (DM) is a metabolic disease defined by elevated blood glucose (BG). DM is a global epidemic and the prevalence is anticipated to continue to increase. The ocular complications of DM negatively impact the quality of life and carry an extremely high economic burden. While systemic control of BG can slow the ocular complications they cannot stop them, especially if clinical symptoms are already present. With the advances in biodegradable polymers, implantable ocular devices can slowly release medication to stop, and in some cases reverse, diabetic complications in the eye. In this review we discuss the ocular complications associated with DM, the treatments available with a focus on localized treatments, and what promising treatments are on the horizon.
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Roberti G, Tanga L, Michelessi M, Quaranta L, Parisi V, Manni G, Oddone F. Cytidine 5'-Diphosphocholine (Citicoline) in Glaucoma: Rationale of Its Use, Current Evidence and Future Perspectives. Int J Mol Sci 2015; 16:28401-17. [PMID: 26633368 PMCID: PMC4691046 DOI: 10.3390/ijms161226099] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2015] [Revised: 11/17/2015] [Accepted: 11/19/2015] [Indexed: 11/30/2022] Open
Abstract
Cytidine 5'-diphosphocholine or citicoline is an endogenous compound that acts in the biosynthetic pathway of phospholipids of cell membranes, particularly phosphatidylcholine, and it is able to increase neurotrasmitters levels in the central nervous system. Citicoline has shown positive effects in Parkinson's disease and Alzheimer's disease, as well as in amblyopia. Glaucoma is a neurodegenerative disease currently considered a disease involving ocular and visual brain structures. Neuroprotection has been proposed as a valid therapeutic option for those patients progressing despite a well-controlled intraocular pressure, the main risk factor for the progression of the disease. The aim of this review is to critically summarize the current evidence about the effect of citicoline in glaucoma.
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Affiliation(s)
- Gloria Roberti
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy.
| | - Lucia Tanga
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy.
| | | | - Luciano Quaranta
- DSMC, Università degli studi di Brescia, USVD "Centro per lo studio del Glaucoma" P.le Spedali Civili, 1, 25123 Brescia, Italy.
| | - Vincenzo Parisi
- IRCCS-Fondazione GB Bietti, Via Livenza, 3, 00198 Rome, Italy.
| | - Gianluca Manni
- DSCMT, Università di Roma Tor Vergata, Viale Oxford 81, 00133 Rome, Italy.
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Parisi V, Centofanti M, Ziccardi L, Tanga L, Michelessi M, Roberti G, Manni G. Treatment with citicoline eye drops enhances retinal function and neural conduction along the visual pathways in open angle glaucoma. Graefes Arch Clin Exp Ophthalmol 2015; 253:1327-40. [PMID: 26004075 DOI: 10.1007/s00417-015-3044-9] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2015] [Revised: 04/07/2015] [Accepted: 04/29/2015] [Indexed: 10/23/2022] Open
Abstract
PURPOSE To evaluate the retinal function and the neural conduction along the visual pathways after treatment with citicoline eye drops in patients with open angle glaucoma (OAG). METHODS Fifty-six OAG patients (mean age 52.4 ± 4.72 years, IOP <18 mmHg with beta-blocker monotherapy only) were enrolled. Of these, 47 eyes completed the study: 24 OAG eyes were treated with topical citicoline (OMK1®, Omikron Italia, 3 drops/day) (GC eyes) over a 4-month period (month 4) followed by a 2-month period of citicoline wash-out (month 6), and another 23 OAG eyes were only treated with beta-blocker monotherapy (GP eyes). In GC and GP eyes, pattern electroretinogram (PERG) and visual evoked potentials (VEP) were assessed at baseline and at months 4 and 6 in both groups. RESULTS At baseline, similar (ANOVA, p > 0.01) PERG and VEP values in GC and GP eyes were observed. After treatment with topical citicoline, a significant (p < 0.01) increase of PERG P50-N95 and VEP N75-P100 amplitudes, and a significant (p < 0.01) shortening of VEP P100 implicit times were found. In GC eyes, the shortening of VEP P100 implicit times was correlated significantly (p < 0.01) with the increase of PERG P50-N95 amplitudes. After a 2-month period of topical Citicoline wash-out, PERG and VEP values were similar (p > 0.01) to baseline ones. GP eyes showed not significant changes of PERG and VEP values during the entire follow-up. CONCLUSIONS Topical treatment with citicoline in OAG eyes induces an enhancement of the retinal bioelectrical responses (increase of PERG amplitude) with a consequent improvement of the bioelectrical activity of the visual cortex (shortening and increase of VEP implicit time and amplitude, respectively).
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Affiliation(s)
- Vincenzo Parisi
- "G.B. Bietti" Foundation for Study and Research in Ophthalmology - IRCCS, Via Livenza 3, 000198, Rome, Italy
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Primary retinal cultures as a tool for modeling diabetic retinopathy: an overview. BIOMED RESEARCH INTERNATIONAL 2015; 2015:364924. [PMID: 25688355 PMCID: PMC4320900 DOI: 10.1155/2015/364924] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Revised: 12/04/2014] [Accepted: 12/23/2014] [Indexed: 12/21/2022]
Abstract
Experimental models of diabetic retinopathy (DR) have had a crucial role in the comprehension of the pathophysiology of the disease and the identification of new therapeutic strategies. Most of these studies have been conducted in vivo, in animal models. However, a significant contribution has also been provided by studies on retinal cultures, especially regarding the effects of the potentially toxic components of the diabetic milieu on retinal cell homeostasis, the characterization of the mechanisms on the basis of retinal damage, and the identification of potentially protective molecules. In this review, we highlight the contribution given by primary retinal cultures to the study of DR, focusing on early neuroglial impairment. We also speculate on possible themes into which studies based on retinal cell cultures could provide deeper insight.
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Bikbova G, Oshitari T, Baba T, Yamamoto S. Altered Expression of NF- κ B and SP1 after Exposure to Advanced Glycation End-Products and Effects of Neurotrophic Factors in AGEs Exposed Rat Retinas. J Diabetes Res 2015; 2015:543818. [PMID: 26078979 PMCID: PMC4452840 DOI: 10.1155/2015/543818] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2014] [Revised: 04/04/2015] [Accepted: 04/04/2015] [Indexed: 12/31/2022] Open
Abstract
To determine the effect of advanced glycation end-products (AGEs) on neurite regeneration, and also to determine the regenerative effects of different neurotrophic factors (NTFs) on rat retinal explants, the retinas of SD rats were cultured in three-dimensional collagen gels and incubated in 6 types of media: (1) serum-free control culture media; (2) 100 μg/mL AGEs-BSA media; (3) AGEs-BSA + 100 ng/mL neurotrophin-4 (NT-4) media; (4) AGEs-BSA + 100 ng/mL hepatocyte growth factor media; (5) AGEs-BSA + 100 ng/mL glial cell line-derived neurotrophic factor media; or (6) AGEs-BSA + 100 µM tauroursodeoxycholic acid media. After 7 days, the number of regenerating neurites was counted. The explants were immunostained for nuclear factor-κB (NF-κB) and specificity protein 1 (SP1). Statistical analyses were performed by one-way ANOVA. In retinas incubated with AGEs, the numbers of neurites were fewer than in control. All of the NTFs increased the number of neurites, and the increase was more significant in the NT-4 group. The number of NF-κB and SP1 immunopositive cells was higher in retinas exposed to AGEs than in control. All of the NTFs decreased the number of NF-κB immunopositive cells but did not significantly affect SP1 expression. These results demonstrate the potential of the NTFs as axoprotectants in AGEs exposed retinal neurons.
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Affiliation(s)
- Guzel Bikbova
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, Chiba Prefecture 260-8670, Japan
| | - Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, Chiba Prefecture 260-8670, Japan
- *Toshiyuki Oshitari:
| | - Takayuki Baba
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, Chiba Prefecture 260-8670, Japan
| | - Shuichi Yamamoto
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba, Chiba Prefecture 260-8670, Japan
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Bikbova G, Oshitari T, Yamamoto S. Neuronal cell death and regeneration in diseases associated with advanced glycation end-products accumulation. Neural Regen Res 2014; 9:701-2. [PMID: 25206875 PMCID: PMC4146263 DOI: 10.4103/1673-5374.131569] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/19/2014] [Indexed: 12/18/2022] Open
Affiliation(s)
- Guzel Bikbova
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Chiba, Japan
| | - Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Chiba, Japan
| | - Shuichi Yamamoto
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Chiba, Japan
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Neuroprotection by rat Müller glia against high glucose-induced neurodegeneration through a mechanism involving ERK1/2 activation. Exp Eye Res 2014; 125:20-9. [DOI: 10.1016/j.exer.2014.05.011] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Revised: 04/17/2014] [Accepted: 05/15/2014] [Indexed: 12/15/2022]
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Matteucci A, Varano M, Gaddini L, Mallozzi C, Villa M, Pricci F, Malchiodi-Albedi F. Neuroprotective effects of citicoline in in vitro models of retinal neurodegeneration. Int J Mol Sci 2014; 15:6286-97. [PMID: 24736780 PMCID: PMC4013628 DOI: 10.3390/ijms15046286] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2014] [Revised: 03/11/2014] [Accepted: 03/25/2014] [Indexed: 01/19/2023] Open
Abstract
In recent years, citicoline has been the object of remarkable interest as a possible neuroprotectant. The aim of this study was to investigate if citicoline affected cell survival in primary retinal cultures and if it exerted neuroprotective activity in conditions modeling retinal neurodegeneration. Primary retinal cultures, obtained from rat embryos, were first treated with increasing concentrations of citicoline (up to 1000 μM) and analyzed in terms of apoptosis and caspase activation and characterized by immunocytochemistry to identify neuronal and glial cells. Subsequently, excitotoxic concentration of glutamate or High Glucose-containing cell culture medium (HG) was administered as well-known conditions modeling neurodegeneration. Glutamate or HG treatments were performed in the presence or not of citicoline. Neuronal degeneration was evaluated in terms of apoptosis and loss of synapses. The results showed that citicoline did not cause any damage to the retinal neuroglial population up to 1000 μM. At the concentration of 100 μM, it was able to counteract neuronal cell damage both in glutamate- and HG-treated retinal cultures by decreasing proapoptotic effects and contrasting synapse loss. These data confirm that citicoline can efficiently exert a neuroprotective activity. In addition, the results suggest that primary retinal cultures, under conditions inducing neurodegeneration, may represent a useful system to investigate citicoline neuroprotective mechanisms.
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Affiliation(s)
- Andrea Matteucci
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
| | - Monica Varano
- GB Bietti Eye Foundation IRCCS, Via Livenza, 3, Rome 00198, Italy.
| | - Lucia Gaddini
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
| | - Cinzia Mallozzi
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
| | - Marika Villa
- GB Bietti Eye Foundation IRCCS, Via Livenza, 3, Rome 00198, Italy.
| | - Flavia Pricci
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
| | - Fiorella Malchiodi-Albedi
- Department of Cell Biology and Neuroscience, Istituto Superiore di Sanità, Viale Regina Elena, 299, Rome 00161, Italy.
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Mysona BA, Shanab AY, Elshaer SL, El-Remessy AB. Nerve growth factor in diabetic retinopathy: beyond neurons. EXPERT REVIEW OF OPHTHALMOLOGY 2014; 9:99-107. [PMID: 25031607 PMCID: PMC4096131 DOI: 10.1586/17469899.2014.903157] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Diabetic retinopathy (DR), a major ocular complication of diabetes, is a leading cause of blindness in US working age adults with limited treatments. Neurotrophins (NTs), a family of proteins essential for growth, differentiation and survival of retinal neurons, have emerged as potential players in the pathogenesis of DR. NTs can signal through their corresponding tropomyosin kinase related receptor to mediate cell survival or through the p75 neurotrophin receptor with the co-receptor, sortilin, to mediate cell death. This review focuses on the role of NGF, the first discovered NT, in the development of DR. Impaired processing of proNGF has been found in ocular fluids from diabetic patients as well as experimental models. Evidence from literature and our studies support the notion that NTs appear to play multiple potential roles in DR, hence, understanding their contribution to DR may lead to promising therapeutic approaches for this devastating disease.
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Affiliation(s)
- Barbara A Mysona
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, USA and Culver Vision Discovery Institute, Georgia Regents University, Augusta, GA, USA and Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA
| | - Ahmed Y Shanab
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, USA and Culver Vision Discovery Institute, Georgia Regents University, Augusta, GA, USA and Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA
| | - Sally L Elshaer
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, USA and Culver Vision Discovery Institute, Georgia Regents University, Augusta, GA, USA and Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA
| | - Azza B El-Remessy
- Program in Clinical and Experimental Therapeutics, College of Pharmacy, University of Georgia, Augusta, GA, USA and Culver Vision Discovery Institute, Georgia Regents University, Augusta, GA, USA and Charlie Norwood Veterans Affairs Medical Center, Augusta, GA, USA
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Increased expression of phosphorylated c-Jun and phosphorylated c-Jun N-terminal kinase associated with neuronal cell death in diabetic and high glucose exposed rat retinas. Brain Res Bull 2013; 101:18-25. [PMID: 24333191 DOI: 10.1016/j.brainresbull.2013.12.002] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2013] [Revised: 12/01/2013] [Accepted: 12/02/2013] [Indexed: 01/01/2023]
Abstract
The aim of this study is to examine whether the increased expression of phosphorylated c-Jun (p-c-Jun) and phosphorylated c-Jun N-terminal kinase (p-JNK) are significantly associated with neuronal cell death in diabetic rat retinas and retinas exposed to high glucose. Retinas isolated from six adult male Sprague-Dawley rats and six streptozotocin-induced diabetic rats (DM) were cultured in serum-free medium. The explants from non-diabetic controls were cultured in normal-glucose (N) or high-glucose (HG) medium. Furthermore, neurotrophin-4 (NT-4) and Taurine-conjugated ursodeoxycholic acid (TUDCA) were incubated in HG medium. After 7 days, the numbers of regenerating neurites were counted per explant. After counting, the explants were fixed, cryosectioned, and stained by TUNEL, and also immunostained for p-c-Jun and p-JNK. The numbers of TUNEL-positive, p-c-Jun- and p-JNK-immunopositive cells in the GCL were significantly higher and the numbers of regenerating neurites were significantly lower in the HG and the DM groups than in the N groups. In the HG groups supplemented with NT-4 and TUDCA, the numbers of TUNEL-positive, p-c-Jun- and p-JNK-immunopositive cells were significantly lower and the numbers of neurites were significantly higher than in the HG group without NT-4 and TUDCA. Increased expression of p-c-Jun and p-JNK is associated with neuronal cell death in diabetic rat retinas and retinas exposed to high glucose. Neuroprotective effect of TUDCA and NT-4 is correlated with the suppression of p-c-Jun and p-JNK expression. These results provide a better understanding of the neurodegenerative process underlying DR.
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Oshitari T, Yamamoto S, Roy S. Increased Expression of c-Fos, c-Jun and c-Jun N-Terminal Kinase Associated with Neuronal Cell Death in Retinas of Diabetic Patients. Curr Eye Res 2013; 39:527-31. [DOI: 10.3109/02713683.2013.833248] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
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Bikbova G, Oshitari T, Yamamoto S. Neurite regeneration in adult rat retinas exposed to advanced glycation end-products and regenerative effects of neurotrophin-4. Brain Res 2013; 1534:33-45. [PMID: 23973749 DOI: 10.1016/j.brainres.2013.08.027] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2013] [Revised: 08/14/2013] [Accepted: 08/15/2013] [Indexed: 11/26/2022]
Abstract
The purpose of this study was to determine the effect of low concentrations of advanced glycation end-products on neurite regeneration in isolated rat retinas, and to determine the effects of neurotrophin-4 on regeneration in advanced glycation end-products exposed retinas. Retinal explants of 4 adult Sprague-Dawley rats were cultured on collagen gel and were incubated in; (1) serum-free control culture media, (2) glucose-advanced glycation end-products-bovine serum albumin media, (3) glycolaldehyde-advanced glycation end-products-bovine serum albumin media, (4) glyceraldehyde-advanced glycation end-products-bovine serum albumin media, (5) glucose-advanced glycation end-products+neurotrophin-4 media, (6) glycolaldehyde-advanced glycation end-products+neurotrophin-4 media, or (7) glyceraldehyde-advanced glycation end-products+neurotrophin-4 supplemented culture media. After 7 days, the number of regenerating neurites from the explants was counted. Then, explants were fixed, cryosectioned, and stained for TUNEL. The ratio of TUNEL-positive cells to all cells in the ganglion cell layer was determined. Immunohistochemical examinations for the active-form of caspase-9 and apoptosis-inducing factor were performed. In retinas incubated with advanced glycation end-products containing media, the number of regenerating neurites were fewer than in retinas without advanced glycation end-products, and the number of TUNEL-positive cells and caspase-9- and apoptosis-inducing factor-immunopositive cells was significantly higher than in control media. Neurotrophin-4 supplementation increased the numbers of regenerating neuritis, and the number of TUNEL-positives, caspase-9-, and apoptosis-inducing factor-immunopositive cells were significantly fewer than that in advanced glycation end-products without neurotrophin-4 media. Low doses of advanced glycation end-products impede neurite regeneration in the rat retinas. Neurotrophin-4 significantly enhances neurite regeneration in retinas exposed to advanced glycation end-products.
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Affiliation(s)
- Guzel Bikbova
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Chiba, Japan
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Hu J, Wu Q, Li T, Chen Y, Wang S. Inhibition of high glucose-induced VEGF release in retinal ganglion cells by RNA interference targeting G protein-coupled receptor 91. Exp Eye Res 2013; 109:31-9. [DOI: 10.1016/j.exer.2013.01.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Revised: 12/14/2012] [Accepted: 01/21/2013] [Indexed: 11/29/2022]
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Pascale A, Drago F, Govoni S. Protecting the retinal neurons from glaucoma: lowering ocular pressure is not enough. Pharmacol Res 2012; 66:19-32. [PMID: 22433276 DOI: 10.1016/j.phrs.2012.03.002] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 02/28/2012] [Accepted: 03/05/2012] [Indexed: 01/01/2023]
Abstract
The retina is theater of a number of biochemical reactions allowing, within its layers, the conversion of light impulses into electrical signals. The axons of the last neuronal elements, the ganglion cells, form the optic nerve and transfer the signals to the brain. Therefore, an appropriate cellular communication, not only within the different retinal cells, but also between the retina itself and the other brain structures, is fundamental. One of the most diffuse pathologies affecting retinal function and communication, which thus reverberates in the whole visual system, is glaucoma. This insidious disease is characterized by a progressive optic nerve degeneration and sight loss which may finally lead to irreversible blindness. Nevertheless, the progressive nature of this pathology offers an opportunity for therapeutic intervention. To better understand the cellular processes implicated in the development of glaucoma useful to envision a targeted pharmacological strategy, this manuscript first examines the complex cellular and functional organization of the retina and subsequently identifies the targets sensitive to neurodegeneration. Within this context, high ocular pressure represents a key risk factor. However, recent literature findings highlight the concept that lowering ocular pressure is not enough to prevent/slow down glaucomatous damage, suggesting the importance of combining the hypotensive treatment with other pharmacological approaches, such as the use of neuroprotectants. Therefore, this important and more novel aspect is extensively considered in this review, also emphasizing the idea that the neuroprotective strategy should be extended to the entire visual system and not restricted to the retina.
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Affiliation(s)
- Alessia Pascale
- Department of Drug Sciences, Section of Pharmacology, University of Pavia, Pavia, Italy
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47
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Protective role of somatostatin receptor 2 against retinal degeneration in response to hypoxia. Naunyn Schmiedebergs Arch Pharmacol 2012; 385:481-94. [DOI: 10.1007/s00210-012-0735-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2011] [Accepted: 01/25/2012] [Indexed: 12/20/2022]
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48
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Oshitari T, Yoshida-Hata N, Yamamoto S. Effect of neurotrophin-4 on endoplasmic reticulum stress-related neuronal apoptosis in diabetic and high glucose exposed rat retinas. Neurosci Lett 2011; 501:102-6. [PMID: 21767604 DOI: 10.1016/j.neulet.2011.06.057] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2011] [Revised: 06/10/2011] [Accepted: 06/28/2011] [Indexed: 02/02/2023]
Abstract
The purpose of this study was to investigate the effect of NT-4 on the endoplasmic reticulum (ER) stress-related apoptosis of retinal neurons of isolated retinas. The retinas were isolated from normal and diabetic rats, and the normal retinas were exposed to high glucose (HG). Our results showed that the number of TUNEL-positive, and PERK- and CHOP-positive cells was significantly higher in diabetic and HG exposed retinas than in normal retinas. In diabetic and HG exposed retinas supplemented with NT-4, the number of TUNEL-positive, and PERK- and CHOP-positive cells was significantly lower than in retinas without NT-4. The neuroprotective effect of NT-4 on retinas cultured under diabetic stress was correlated with the suppression in the expression of PERK and CHOP, ER stress-related factors.
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Affiliation(s)
- Toshiyuki Oshitari
- Department of Ophthalmology and Visual Science, Chiba University Graduate School of Medicine, Inohana 1-8-1, Chuo-ku, Chiba 260-8670, Japan.
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49
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Marra C, Gomes Moret D, de Souza Corrêa A, Chagas da Silva F, Moraes P, Linden R, Sholl-Franco A. Protein kinases JAK and ERK mediate protective effect of interleukin-2 upon ganglion cells of the developing rat retina. J Neuroimmunol 2011; 233:120-6. [PMID: 21262542 DOI: 10.1016/j.jneuroim.2010.12.008] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 12/14/2010] [Accepted: 12/19/2010] [Indexed: 01/12/2023]
Abstract
Interleukin-2 (IL-2), a prototypical pro-inflammatory cytokine firstly related to T cells differentiation, exerts pleiotrophic functions in several areas of the central nervous system. Previously we had described the neurotrophic roles of this interleukin upon retinal neurons. Therefore, the aim of this work was to investigate the signaling pathways involved in the neuroprotective effect of IL-2 on axotomized RGC. Herein we demonstrated that at postnatal day 2 IL-2 receptor α subunit (IL-2Rα) is expressed in inner plexiform layer, retinal ganglion cells layer and retinal nerve fibers layer. Moreover, using a model of organotypic retinal explants and rhodamine dextran retrograde labeling for specifically quantify RGC, we showed that IL-2 increased the survival of axotomized RGC after 2 (85.43±5.43%) and 5 (50.23%±5.32) days in vitro. Western blot analysis demonstrated that IL-2 treatment increased the phosphorilation of both extracellular signal-regulated kinases (ERK)1/2 and AKT (~two fold). However, its neuroprotective effect upon RGC was dependent of Janus kinase (JAK) and ERK1/2 activity but not of AKT activity. Taken together our results showed that the IL-2 neuroprotective action upon RGC in vitro is mediated by JAK and ERK1/2 activation.
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Affiliation(s)
- Camila Marra
- Programa de Neurobiologia, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Cidade Universitária, 21941-902Rio de Janeiro, RJ, Brazil
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