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Amankwa CE, Acha LG, Dibas A, Chavala SH, Roth S, Mathew B, Acharya S. Neuroprotective and Anti-Inflammatory Activities of Hybrid Small-Molecule SA-10 in Ischemia/Reperfusion-Induced Retinal Neuronal Injury Models. Cells 2024; 13:396. [PMID: 38474360 PMCID: PMC10931063 DOI: 10.3390/cells13050396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 02/16/2024] [Accepted: 02/20/2024] [Indexed: 03/14/2024] Open
Abstract
Embolism, hyperglycemia, high intraocular pressure-induced increased reactive oxygen species (ROS) production, and microglial activation result in endothelial/retinal ganglion cell death. Here, we conducted in vitro and in vivo ischemia/reperfusion (I/R) efficacy studies of a hybrid antioxidant-nitric oxide donor small molecule, SA-10, to assess its therapeutic potential for ocular stroke. METHODS To induce I/R injury and inflammation, we subjected R28 and primary microglial cells to oxygen glucose deprivation (OGD) for 6 h in vitro or treated these cells with a cocktail of TNF-α, IL-1β and IFN-γ for 1 h, followed by the addition of SA-10 (10 µM). Inhibition of microglial activation, ROS scavenging, cytoprotective and anti-inflammatory activities were measured. In vivo I/R-injured mouse retinas were treated with either PBS or SA-10 (2%) intravitreally, and pattern electroretinogram (ERG), spectral-domain optical coherence tomography, flash ERG and retinal immunocytochemistry were performed. RESULTS SA-10 significantly inhibited microglial activation and inflammation in vitro. Compared to the control, the compound SA-10 significantly attenuated cell death in both microglia (43% vs. 13%) and R28 cells (52% vs. 17%), decreased ROS (38% vs. 68%) production in retinal microglia cells, preserved neural retinal function and increased SOD1 in mouse eyes. CONCLUSION SA-10 is protective to retinal neurons by decreasing oxidative stress and inflammatory cytokines.
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Affiliation(s)
- Charles E. Amankwa
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (C.E.A.); (A.D.); (S.H.C.)
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Lorea Gamboa Acha
- Department of Anesthesiology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA; (L.G.A.); (S.R.)
| | - Adnan Dibas
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (C.E.A.); (A.D.); (S.H.C.)
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Sai H. Chavala
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (C.E.A.); (A.D.); (S.H.C.)
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
| | - Steven Roth
- Department of Anesthesiology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA; (L.G.A.); (S.R.)
| | - Biji Mathew
- Department of Anesthesiology, College of Medicine, University of Illinois at Chicago, Chicago, IL 60612, USA; (L.G.A.); (S.R.)
| | - Suchismita Acharya
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, TX 76107, USA; (C.E.A.); (A.D.); (S.H.C.)
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, TX 76107, USA
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Murotomi K, Umeno A, Shichiri M, Tanito M, Yoshida Y. Significance of Singlet Oxygen Molecule in Pathologies. Int J Mol Sci 2023; 24:ijms24032739. [PMID: 36769060 PMCID: PMC9917472 DOI: 10.3390/ijms24032739] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2022] [Revised: 01/22/2023] [Accepted: 01/26/2023] [Indexed: 02/04/2023] Open
Abstract
Reactive oxygen species, including singlet oxygen, play an important role in the onset and progression of disease, as well as in aging. Singlet oxygen can be formed non-enzymatically by chemical, photochemical, and electron transfer reactions, or as a byproduct of endogenous enzymatic reactions in phagocytosis during inflammation. The imbalance of antioxidant enzymes and antioxidant networks with the generation of singlet oxygen increases oxidative stress, resulting in the undesirable oxidation and modification of biomolecules, such as proteins, DNA, and lipids. This review describes the molecular mechanisms of singlet oxygen production in vivo and methods for the evaluation of damage induced by singlet oxygen. The involvement of singlet oxygen in the pathogenesis of skin and eye diseases is also discussed from the biomolecular perspective. We also present our findings on lipid oxidation products derived from singlet oxygen-mediated oxidation in glaucoma, early diabetes patients, and a mouse model of bronchial asthma. Even in these diseases, oxidation products due to singlet oxygen have not been measured clinically. This review discusses their potential as biomarkers for diagnosis. Recent developments in singlet oxygen scavengers such as carotenoids, which can be utilized to prevent the onset and progression of disease, are also described.
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Affiliation(s)
- Kazutoshi Murotomi
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba 305-8566, Japan
| | - Aya Umeno
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan
| | - Mototada Shichiri
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Ikeda 563-8577, Japan
- Correspondence: ; Tel.: +81-72-751-8234
| | - Masaki Tanito
- Department of Ophthalmology, Shimane University Faculty of Medicine, Izumo 693-8501, Japan
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Umeno A, Yoshida Y, Kaidzu S, Tanito M. Positive Association between Aqueous Humor Hydroxylinoleate Levels and Intraocular Pressure. Molecules 2022; 27:molecules27072215. [PMID: 35408614 PMCID: PMC9000355 DOI: 10.3390/molecules27072215] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2022] [Revised: 03/28/2022] [Accepted: 03/28/2022] [Indexed: 02/01/2023] Open
Abstract
We previously proposed the total assessment of hydroxylinoleates (HODEs) by LC-MS/MS after saponification and reduction of the biologic samples as biomarkers to investigate pathogenesis, disease progression, and prognosis. In this study, HODE levels were estimated in aqueous humor (AH) samples from 63 eyes (41 Japanese subjects; 15 men; mean age, 77.3 ± 6.8 years) with primary open-angle glaucoma (POAG) or cataracts. The correlations between intraocular HODE levels and background parameters, including intraocular pressure (IOP), were analyzed to assess the possible involvement of oxidative stress in glaucoma pathology. Univariate analyses showed that linoleic acid (LA) (p = 0.034) and arachidonic acid (AA) (p = 0.0041) levels were associated negatively with age; 13-(Z,E)-HODE (p = 0.018) and 13-(E,E)-HODE (p = 0.021) were associated positively with IOP; 9-(Z,E)-HODE (p = 0.039), 13-(Z,E)-HODE (p = 0.021), totally assessed-HODE (t-HODE, p = 0.023), LA (p = 0.0080), and AA (p = 0.0051) were higher in eyes with glaucoma than cataract. No gender differences were seen. A mixed-effect regression model showed that higher 13-(Z,E)-HODE (p = 0.0040) and higher t-HODE (p = 0.040) were associated with glaucoma rather than cataracts; and higher levels of 13-(Z,E)-HODE/LA (p = 0.043), 13-(E,E)-HODE/LA (p = 0.042), 13-(Z,E)-HODE (p = 0.0054), and 13-(E,E)-HODE (p = 0.027) were associated with higher IOP. Linoleate-derived oxidation products were quantified successfully in AH samples from patients with glaucoma and cataracts. A free radical oxidation mechanism can be associated with IOP elevation, while enzymatic oxidation may be involved, specifically, in the pathogenesis of POAG.
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Affiliation(s)
- Aya Umeno
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Izumo 693-8501, Japan; (A.U.); (S.K.)
- Computational Bio Big Data Open Innovation Laboratory (CBBD-OIL), National Institute of Advanced Industrial Science and Technology, Tokyo 100-0004, Japan
- Health Research Institute, National Institute of Advanced Industrial Science and Technology, Takamatsu 761-0301, Japan
| | - Yasukazu Yoshida
- Head Office Laboratory, LG Japan Lab Inc., Kanagawa 220-0011, Japan;
| | - Sachiko Kaidzu
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Izumo 693-8501, Japan; (A.U.); (S.K.)
| | - Masaki Tanito
- Department of Ophthalmology, Faculty of Medicine, Shimane University, Izumo 693-8501, Japan; (A.U.); (S.K.)
- Correspondence: ; Tel.: +81-853-20-2284
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4
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Cáceres-Vélez PR, Hui F, Hercus J, Bui B, Jusuf PR. Restoring the oxidative balance in age-related diseases - An approach in glaucoma. Ageing Res Rev 2022; 75:101572. [PMID: 35065274 DOI: 10.1016/j.arr.2022.101572] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Revised: 12/10/2021] [Accepted: 01/18/2022] [Indexed: 02/07/2023]
Abstract
As human life expectancy increases, age-related health issues including neurodegenerative diseases continue to rise. Regardless of genetic or environmental factors, many neurodegenerative conditions share common pathological mechanisms, such as oxidative stress, a hallmark of many age-related health burdens. In this review, we describe oxidative damage and mitochondrial dysfunction in glaucoma, an age-related neurodegenerative eye disease affecting 80 million people worldwide. We consider therapeutic approaches used to counteract oxidative stress in glaucoma, including untapped treatment options such as novel plant-derived antioxidant compounds that can reduce oxidative stress and prevent neuronal loss. We summarize the current pre-clinical models and clinical work exploring the therapeutic potential of a range of candidate plant-derived antioxidant compounds. Finally, we explore advances in drug delivery systems, particular those employing nanotechnology-based carriers which hold significant promise as a carrier for antioxidants to treat age-related disease, thus reviewing the key current state of all of the aspects required towards translation.
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Maekawa S, Sato K, Kokubun T, Himori N, Yabana T, Ohno-Oishi M, Shi G, Omodaka K, Nakazawa T. A Plant-Derived Antioxidant Supplement Prevents the Loss of Retinal Ganglion Cells in the Retinas of NMDA-Injured Mice. Clin Ophthalmol 2022; 16:823-832. [PMID: 35330750 PMCID: PMC8939866 DOI: 10.2147/opth.s354958] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Accepted: 03/02/2022] [Indexed: 11/23/2022] Open
Affiliation(s)
- Shigeto Maekawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Kota Sato
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Taiki Kokubun
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Noriko Himori
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Aging Vision Healthcare, Tohoku University Graduate School of Biomedical Engineering, Sendai, Miyagi, Japan
| | - Takeshi Yabana
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Michiko Ohno-Oishi
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Ge Shi
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Kazuko Omodaka
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Collaborative Program for Ophthalmic Drug Discovery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
- Correspondence: Toru Nakazawa, Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo, Aoba, Sendai, Miyagi, 980-8574, Japan, Tel +81-22-717-7294, Fax +81-22-717-7298, Email
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6
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Neuroprotection in Glaucoma: NAD +/NADH Redox State as a Potential Biomarker and Therapeutic Target. Cells 2021; 10:cells10061402. [PMID: 34198948 PMCID: PMC8226607 DOI: 10.3390/cells10061402] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/24/2021] [Accepted: 05/27/2021] [Indexed: 02/07/2023] Open
Abstract
Glaucoma is the leading cause of irreversible blindness worldwide. Its prevalence and incidence increase exponentially with age and the level of intraocular pressure (IOP). IOP reduction is currently the only therapeutic modality shown to slow glaucoma progression. However, patients still lose vision despite best treatment, suggesting that other factors confer susceptibility. Several studies indicate that mitochondrial function may underlie both susceptibility and resistance to developing glaucoma. Mitochondria meet high energy demand, in the form of ATP, that is required for the maintenance of optimum retinal ganglion cell (RGC) function. Reduced nicotinamide adenine dinucleotide (NAD+) levels have been closely correlated to mitochondrial dysfunction and have been implicated in several neurodegenerative diseases including glaucoma. NAD+ is at the centre of various metabolic reactions culminating in ATP production—essential for RGC function. In this review we present various pathways that influence the NAD+(H) redox state, affecting mitochondrial function and making RGCs susceptible to degeneration. Such disruptions of the NAD+(H) redox state are generalised and not solely induced in RGCs because of high IOP. This places the NAD+(H) redox state as a potential systemic biomarker for glaucoma susceptibility and progression; a hypothesis which may be tested in clinical trials and then translated to clinical practice.
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Asano T, Nagayo Y, Tsuda S, Ito A, Kobayashi W, Fujita K, Sato K, Nishiguchi KM, Kunikata H, Fujioka H, Kamiya M, Urano Y, Nakazawa T. Companion Diagnosis for Retinal Neuroprotective Treatment by Real-Time Imaging of Calpain Activation Using a Novel Fluorescent Probe. Bioconjug Chem 2020; 31:2241-2251. [PMID: 32840357 DOI: 10.1021/acs.bioconjchem.0c00435] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Calpain activation induces retinal ganglion cell (RGC) death, while calpain inhibition suppresses RGC death, in animal studies. However, the role of calpain in human retinal disease is unclear. This study investigated a new strategy to study the role of calpain based on real-time imaging. We synthesized a novel fluorescent probe for calpain, acetyl-l-leucyl-l-methionine-hydroxymethyl rhodamine green (Ac-LM-HMRG) and used it for real-time imaging of calpain activation. The toxicity of Ac-LM-HMRG was evaluated with a lactate dehydrogenase cytotoxicity assay, retinal sections, and electroretinograms. Here, we performed real-time imaging of calpain activation in a rat model. First, we administered N-methyl-d-aspartate (NMDA) to induce retinal injury. Twenty minutes later, we administered an intravitreal injection of Ac-LM-HMRG. Real-time imaging was then completed with a noninvasive confocal scanning laser ophthalmoscope. The inhibitory effect of SNJ-1945 against calpain activation was also examined with the same real-time imaging method. Ac-LM-HMRG had no toxic effects. The number of Ac-LM-HMRG-positive cells in real-time imaging significantly increased after NMDA injury, and SNJ-1945 significantly lowered the number of Ac-LM-HMRG-positive cells. Real-time imaging with Ac-LM-HMRG was able to quickly quantify the NMDA-induced activation of calpain and the inhibitory effect of SNJ-1945. This technique, used as a companion diagnostic system, may aid research into the development of new neuroprotective therapies.
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Affiliation(s)
- Toshifumi Asano
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan
| | - Yuri Nagayo
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Satoru Tsuda
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan
| | - Azusa Ito
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan
| | - Wataru Kobayashi
- Department of Retinal Disease Control, Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Kosuke Fujita
- Department of Retinal Disease Control, Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Kota Sato
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.,Collaborative Program of Ophthalmic Drug Discovery, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Koji M Nishiguchi
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi 980-8574, Japan
| | - Hiroshi Kunikata
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.,Department of Retinal Disease Control, Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan
| | - Hiroyoshi Fujioka
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Tokyo 113-8654, Japan
| | - Mako Kamiya
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Yasuteru Urano
- Graduate School of Medicine, The University of Tokyo, Tokyo 113-0033, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, 1-1 Seiryo-machi, Aoba-ku, Sendai, Miyagi 980-8574, Japan.,Department of Retinal Disease Control, Ophthalmology, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan.,Collaborative Program of Ophthalmic Drug Discovery, Tohoku University Graduate School of Medicine, Sendai 980-8574, Japan.,Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Miyagi 980-8574, Japan.,Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Miyagi 980-8574, Japan
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8
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Ma T, Sun J, Li X, Ma Y, Liu L, Guo L, Liu Q, Sun Y. Optimization of extraction for Anemarrhena asphodeloides Bge. using silica gel-based vortex-homogenized matrix solid-phase dispersion and rapid identification of antioxidant substances. J Sep Sci 2020; 43:2180-2192. [PMID: 32133730 DOI: 10.1002/jssc.202000101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Revised: 02/28/2020] [Accepted: 03/03/2020] [Indexed: 12/30/2022]
Abstract
A novel and simple method was established for the extraction and determination of seven compounds in Anemarrhena asphodeloides Bge. using silica gel-based vortex-homogenized matrix solid-phase dispersion and ultra-high performance liquid chromatography quadrupole-time of-flight mass spectrometer. The conditions for the extraction were optimized. Silica gel was used as the dispersant, 50% methanol-water was selected as an elution solvent and the grinding time was 3 min. Compared with the traditional ultrasonic-assisted extraction, the developed method was rapid and efficient. In order to screen potential antioxidants, extract dealing with the optimized method was applied to a polyamide chromatography column and a D-101 macroporous resin column. Fr.2.2 showed the highest antioxidant activities with the most content of flavonoid. A total of 25 peaks were identified from the active fraction. A 2,2'-diphenyl-1-picrylhydrazyl ultra-high performance liquid chromatography coupled with mass spectrometry approach was adopted for the rapid and exact screening and identification of antioxidant compounds. It indicated that flavonoids exhibited potential antioxidant activities. The antioxidant activities of nine monomeric compounds in vivo were tested. Structure-activity relationships were discussed. Five flavonoids with the concentration of 500 µg/mL would reduce the oxidative stress of PC12 cells that were induced with 2,2'-azobis[2-methylpropionamidine] dihydrochloride.
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Affiliation(s)
- Tiancheng Ma
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China.,School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University, Shenyang, Liaoning, P. R. China
| | - Jia Sun
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Xiangkun Li
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Yukun Ma
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Lei Liu
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Lina Guo
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Qi Liu
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
| | - Yu Sun
- Research Institute of Medicine and Pharmacy, Qiqihar Medical University, Qiqihar, Heilongjiang, P. R. China
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Umeno A, Tanito M, Kaidzu S, Takai Y, Yoshida Y. Involvement of free radical-mediated oxidation in the pathogenesis of pseudoexfoliation syndrome detected based on specific hydroxylinoleate isomers. Free Radic Biol Med 2020; 147:61-68. [PMID: 31852620 DOI: 10.1016/j.freeradbiomed.2019.12.011] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 11/28/2019] [Accepted: 12/12/2019] [Indexed: 01/19/2023]
Abstract
We reported previously that enzymatic and singlet oxygen-mediated fatty acid oxidation may be major oxidation pathways in subjects with primary open angle glaucoma, based on measurement of serum levels of hydroxylinoleate (HODE) and hydroxyarachidonate (HETE) isomers after reduction and saponification. In this study, we measured serum levels of HODE and HETE isomers to investigate the pathogenesis of exfoliation syndrome (EX). In total, 311 Japanese subjects comprising EX patients (n = 192) and non-glaucomatous control subjects (n = 119) were included in this study. Patients with EX (n = 192) were divided into EX with glaucoma (EXG) and EX without glaucoma (EXS) groups (n = 128 and n = 64, respectively) depending on the intraocular pressure. Total HODE (/linoleic acid) serum levels were significantly (p = 0.0426) higher in the EX group (202.7 ± 153.2 μmol/mol) than in the controls (167.1 ± 105.3 μmol/mol). Among the HODE isomers, the levels of 9-(E,E)-HODEs (p < 0.0001) and 13-(E,E)-HODEs (p < 0.0001), both free radical-mediated oxidation products, were higher in the EX and EXG groups than in the controls, whereas no significant difference was observed between EXS and controls. After adjusting for differences in demographic parameters, multivariate analyses confirmed the association between 9- and 13-(E,E)-HODEs and EX. This is the first report of a dramatic increase in free radical-mediated oxidation products related to the pathogenesis of EX, and our findings suggest that free radical-mediated oxidation can be one of the causes of deterioration in EX.
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Affiliation(s)
- Aya Umeno
- Health Research Institute, National Institute of Advanced Industrial Science and Technology, 2217-14 Hayashicho, Takamatsu, Kagawa, 761-0395, Japan; Department of Ophthalmology, Shimane University Faculty of Medicine, 89-1 Enya, Izumo, Shimane, 693-8501, Japan
| | - Masaki Tanito
- Health Research Institute, National Institute of Advanced Industrial Science and Technology, 2217-14 Hayashicho, Takamatsu, Kagawa, 761-0395, Japan; Department of Ophthalmology, Shimane University Faculty of Medicine, 89-1 Enya, Izumo, Shimane, 693-8501, Japan.
| | - Sachiko Kaidzu
- Department of Ophthalmology, Shimane University Faculty of Medicine, 89-1 Enya, Izumo, Shimane, 693-8501, Japan
| | - Yasuyuki Takai
- Department of Ophthalmology, Shimane University Faculty of Medicine, 89-1 Enya, Izumo, Shimane, 693-8501, Japan
| | - Yasukazu Yoshida
- Health Research Institute, National Institute of Advanced Industrial Science and Technology, 2217-14 Hayashicho, Takamatsu, Kagawa, 761-0395, Japan
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Arkoun B, Galas L, Dumont L, Rives A, Saulnier J, Delessard M, Rondanino C, Rives N. Vitamin E but Not GSH Decreases Reactive Oxygen Species Accumulation and Enhances Sperm Production during In Vitro Maturation of Frozen-Thawed Prepubertal Mouse Testicular Tissue. Int J Mol Sci 2019; 20:ijms20215380. [PMID: 31671759 PMCID: PMC6861907 DOI: 10.3390/ijms20215380] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2019] [Revised: 10/15/2019] [Accepted: 10/16/2019] [Indexed: 02/05/2023] Open
Abstract
Freezing-thawing procedures and in vitro culture conditions are considered as a source of stress associated with increased reactive oxygen species (ROS) generation, leading to a damaged cell aerobic metabolism and consequently to oxidative stress. In the present study, we sought to investigate whether vitamin E (Vit E) or reduced glutathione (GSH) enhances sperm production by decreasing ROS accumulation during in vitro maturation of prepubertal mice testes. Testes of prepubertal mice were cryopreserved using a freezing medium supplemented or not supplemented with Vit E and were cultured after thawing. In presence of Rol alone in culture medium, frozen-thawed (F-T) testicular tissues exhibited a higher ROS accumulation than fresh tissue during in vitro culture. However, Vit E supplementation in freezing, thawing, and culture media significantly decreased cytoplasmic ROS accumulation in F-T testicular tissue during in vitro maturation when compared with F-T testicular tissue cultured in the presence of Rol alone, whereas GSH supplementation in culture medium significantly increased ROS accumulation associated with cytolysis and tissue disintegration. Vit E but not GSH promoted a better in vitro sperm production and was a suitable ROS scavenger and effective molecule to improve the yield of in vitro spermatogenesis from F-T prepubertal mice testes. The prevention of oxidative stress in the cytoplasmic compartment should be regarded as a potential strategy for improving testicular tissue viability and functionality during the freeze-thaw procedure and in vitro maturation.
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Affiliation(s)
- Brahim Arkoun
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Ludovic Galas
- Normandie Univ, UNIROUEN, INSERM, PRIMACEN, 76000 Rouen, France.
| | - Ludovic Dumont
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Aurélie Rives
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Justine Saulnier
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Marion Delessard
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Christine Rondanino
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
| | - Nathalie Rives
- Normandie Univ, UNIROUEN, EA 4308 "Gametogenesis and Gamete Quality", Rouen University Hospital, Biology of Reproduction-CECOS laboratory, 76000 Rouen, France.
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Tawarayama H, Feng Q, Murayama N, Suzuki N, Nakazawa T. Cyclin-Dependent Kinase Inhibitor 2b Mediates Excitotoxicity-Induced Death of Retinal Ganglion Cells. ACTA ACUST UNITED AC 2019; 60:4479-4488. [DOI: 10.1167/iovs.19-27396] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Hiroshi Tawarayama
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
- Division of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Qiwei Feng
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Namie Murayama
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Noriyuki Suzuki
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
| | - Toru Nakazawa
- Department of Ophthalmology, Tohoku University Graduate School of Medicine, Sendai, Japan
- Division of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, Japan
- Division of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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12
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Assessing retinal ganglion cell death and neuroprotective agents using real time imaging. Brain Res 2019; 1714:65-72. [DOI: 10.1016/j.brainres.2019.02.008] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 02/07/2019] [Accepted: 02/08/2019] [Indexed: 01/01/2023]
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Stankowska DL, Dibas A, Li L, Zhang W, Krishnamoorthy VR, Chavala SH, Nguyen TP, Yorio T, Ellis DZ, Acharya S. Hybrid Compound SA-2 is Neuroprotective in Animal Models of Retinal Ganglion Cell Death. Invest Ophthalmol Vis Sci 2019; 60:3064-3073. [PMID: 31348824 DOI: 10.1167/iovs.18-25999] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Purpose Determine the toxicity, bioavailability in the retina, and neuroprotective effects of a hybrid antioxidant-nitric oxide donor compound SA-2 against oxidative stress-induced retinal ganglion cell (RGC) death in neurodegenerative animal models. Methods Optic nerve crush (ONC) and ischemia reperfusion (I/R) injury models were used in 12-week-old C57BL/6J mice to mimic conditions of glaucomatous neurodegeneration. Mice were treated intravitreally with either vehicle or SA-2. Retinal thickness was measured by spectral-domain optical coherence tomography (SD-OCT). The electroretinogram and pattern ERG (PERG) were used to assess retinal function. RGC survival was determined by counting RBPMS-positive RGCs and immunohistochemical analysis of superoxide dismutase 1 (SOD1) levels was carried out in the retina sections. Concentrations of SA-2 in the retina and choroid were determined using HPLC and MS. In addition, the direct effect of SA-2 treatment on RGC survival was assessed in ex vivo rat retinal explants under hypoxic (0.5% O2) conditions. Results Compound SA-2 did not induce any appreciable change in retinal thickness, or in a- or b-wave amplitude in naive animals. SA-2 was found to be bioavailable in both the retina and choroid after a single intravitreal injection (2% wt/vol). An increase in SOD1 levels in the retina of mice subjected to ONC and SA-2 treatment, suggests an enhancement in antioxidant activity. SA-2 provided significant (P < 0.05) RGC protection in all three of the tested RGC injury models in rodents. PERG amplitudes were significantly higher in both I/R and ONC mouse eyes following SA-2 treatment (P ≤ 0.001) in comparison with the vehicle and control groups. Conclusions Compound SA-2 was effective in preventing RGC death and loss of function in three different rodent models of acute RGC injury: ONC, I/R, and hypoxia.
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Affiliation(s)
- Dorota L Stankowska
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Adnan Dibas
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Linya Li
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Wei Zhang
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Vignesh R Krishnamoorthy
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Sai H Chavala
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Tam Phung Nguyen
- Department of Bioengineering, The University of Texas at Arlington, Arlington, Texas, United States
| | - Thomas Yorio
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Dorette Z Ellis
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
- Department of Pharmaceutical Sciences, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Suchismita Acharya
- Department of Pharmacology and Neuroscience, University of North Texas Health Science Center, Fort Worth, Texas, United States
- North Texas Eye Research Institute, University of North Texas Health Science Center, Fort Worth, Texas, United States
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Comprehensive measurements of hydroxylinoleate and hydroxyarachidonate isomers in blood samples from primary open-angle glaucoma patients and controls. Sci Rep 2019; 9:2171. [PMID: 30778084 PMCID: PMC6379359 DOI: 10.1038/s41598-018-36952-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 11/27/2018] [Indexed: 12/12/2022] Open
Abstract
We previously reported that lower systemic antioxidant capacity is involved in primary open-angle glaucoma (POAG) and exfoliation syndrome pathogeneses as measured by ferric-reducing activity. In the present study, we measured hydroxylinoleate (HODE) and hydroxyarachidonate (HETE) isomer serum levels after sample reduction and saponification to investigate POAG pathogenesis. POAG patients (n = 198) were recruited and divided into normal- and high-tension glaucoma groups (n = 84 and 114, respectively) depending on intraocular pressure. Total HODE (/linoleic acid) and HETE (/arachidonic acid) serum levels were significantly higher in the POAG group (211.9 ± 143.0 and 181.0 ± 164.1 µmol/mol, respectively) than in controls (167.1 ± 105.2 and 132.5 ± 139.7 µmol/mol, p = 0.0025 and 0.0101, respectively). The associations between HODEs/HETEs and glaucoma were further confirmed by multivariate analyses after adjusting for differences in demographic parameters. Among the HODE isomers, the levels of 9- and 13-(Z,E)-HODEs (p = 0.0014) and singlet oxygen-specific products (i.e., 10- and 12-(Z,E)-HODEs, p = 0.0345) were higher in the POAG group than in controls, while free radical-mediated oxidation-specific products (i.e., 9- and 13-(E,E)-HODEs, p = 0.0557) demonstrated a marginal difference. Enzymatic and singlet oxygen-mediated fatty acid oxidation may be major pathways of oxidation process in glaucoma subjects.
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Mouse model of ocular hypertension with retinal ganglion cell degeneration. PLoS One 2019; 14:e0208713. [PMID: 30640920 PMCID: PMC6331128 DOI: 10.1371/journal.pone.0208713] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2018] [Accepted: 11/22/2018] [Indexed: 11/16/2022] Open
Abstract
Objectives Ocular hypertension is a primary risk factor for glaucoma and results in retinal ganglion cell (RGC) degeneration. Current animal models of glaucoma lack severe RGC cell death as seen in glaucoma, making assessment of physiological mediators of cell death difficult. We developed a modified mouse model of ocular hypertension whereby long-lasting elevation of intraocular pressure (IOP) is achieved, resulting in significant reproducible damage to RGCs. Results In this model, microbeads are mixed with hyaluronic acid and injected into the anterior chamber of C57BL/6J mice. The hyaluronic acid allows for a gradual release of microbeads, resulting in sustained blockage of Schlemm’s canal. IOP elevation was bimodal during the course of the model’s progression. The first peak occurred 1 hours after beads injection, with an IOP value of 44.69 ± 6.00 mmHg, and the second peak occurred 6–12 days post-induction, with an IOP value of 34.91 ± 5.21 mmHg. RGC damage was most severe in the peripheral retina, with a loss of 64.1% compared to that of untreated eyes, while the midperiphery exhibited a 32.4% loss, 4 weeks following disease induction. Conclusions These results suggest that sustained IOP elevation causes more RGC damage in the periphery than in the midperiphery of the retina. This model yields significant and reproducible RGC degeneration.
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Pinazo-Durán MD, Shoaie-Nia K, Zanón-Moreno V, Sanz-González SM, Benítez del Castillo J, García-Medina JJ. Strategies to Reduce Oxidative Stress in Glaucoma Patients. Curr Neuropharmacol 2018; 16:903-918. [PMID: 28677495 PMCID: PMC6120109 DOI: 10.2174/1570159x15666170705101910] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2017] [Revised: 05/17/2017] [Accepted: 06/22/2017] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Primary open-angle glaucoma (POAG) is a multifactorial pathology involving a variety of pathogenic mechanisms, including oxidative/nitrosative stress. This latter is the consequence of the imbalance between excessive formation and insufficient protection against reactive oxygen/nitrogen species. OBJECTIVE Our main goal is to gather molecular information to better managing pathologic variants that may determine the individual susceptibility to oxidative/nitrosative stress (OS/NS) and POAG. METHOD An extensive search of the scientific literature was conducted using PUBMED, the Web of Science, the Cochrane Library, and other references on the topic of POAG and OS/NS from human and animal model studies published between 2010 and 2017. Finally, 152 works containing relevant information that may help understanding the role of antioxidants, essential fatty acids, natural compounds and other similar strategies for counteracting OS/NS in POAG were considered. RESULTS A wide variety of studies have proven that antioxidants, among them vitamins B3, C and E, Coenzyme Q10 or melatonin, ω-3/ω-6 fatty acids and other natural compounds (such as coffee, green tea, bear bile, gingko biloba, coleus, tropical fruits, etc.,) may help regulating the intraocular pressure as well as protecting the retinal neurons against OS/NS in POAG. CONCLUSION Based on the impact of antioxidants and ω-3/ω-6 fatty acids at the molecular level in the glaucomatous anterior and posterior eye segments, further studies are needed by integrating all issues involved in glaucoma pathogenesis, endogenous and exogenous risk factors and their interactions that will allow us to reach newer effective biotherapies for preventing glaucomatous irreversible blindness.
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Affiliation(s)
- Maria D. Pinazo-Durán
- Address correspondence to this author at the Ophthalmic Research Unit “Santiago Grisolía”/FISABIO, University Hospital Dr. Peset. Ave/ Gaspar Aguilar 90; 46017, Valencia, Spain; Tel: + 34 961622497;, Fax: + 34 961622748; E-mail:
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Abstract
INTRODUCTION Calpains represent a family of neutral, calcium-dependent proteases, which modify the function of their target proteins by partial truncation. These proteases have been implicated in numerous cell functions, including cell division, proliferation, migration, and death. In the CNS, where calpain-1 and calpain-2 are the main calpain isoforms, their activation has been linked to synaptic plasticity as well as to neurodegeneration. This review will focus on the role of calpain-2 in acute neuronal injury and discuss the possibility of developing selective calpain-2 inhibitors for therapeutic purposes. Areas covered: This review covers the literature showing how calpain-2 is implicated in neuronal death in a number of pathological conditions. The possibility of developing new selective calpain-2 inhibitors for treating these conditions is discussed. Expert opinion: As evidence accumulates that calpain-2 activation participates in acute neuronal injury, there is interest in developing therapeutic approaches using selective calpain-2 inhibitors. Recent data indicate the potential use of such inhibitors in various pathologies associated with acute neuronal death. The possibility of extending the use of such inhibitors to more chronic forms of neurodegeneration is discussed.
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Affiliation(s)
- Yubin Wang
- Graduate College of Biomedical Sciences, COMP Western University of Health Sciences 309 E. 2 St., Pomona, CA 91766
| | - Xiaoning Bi
- Department of Basic Science, COMP Western University of Health Sciences 309 E. 2 St., Pomona, CA 91766
| | - Michel Baudry
- Graduate College of Biomedical Sciences, COMP Western University of Health Sciences 309 E. 2 St., Pomona, CA 91766
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Maekawa S, Sato K, Fujita K, Daigaku R, Tawarayama H, Murayama N, Moritoh S, Yabana T, Shiga Y, Omodaka K, Maruyama K, Nishiguchi KM, Nakazawa T. The neuroprotective effect of hesperidin in NMDA-induced retinal injury acts by suppressing oxidative stress and excessive calpain activation. Sci Rep 2017; 7:6885. [PMID: 28761134 PMCID: PMC5537259 DOI: 10.1038/s41598-017-06969-4] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2017] [Accepted: 06/22/2017] [Indexed: 12/21/2022] Open
Abstract
We found that hesperidin, a plant-derived bioflavonoid, may be a candidate agent for neuroprotective treatment in the retina, after screening 41 materials for anti-oxidative properties in a primary retinal cell culture under oxidative stress. We found that the intravitreal injection of hesperidin in mice prevented reductions in markers of the retinal ganglion cells (RGCs) and RGC death after N-methyl-D-aspartate (NMDA)-induced excitotoxicity. Hesperidin treatment also reduced calpain activation, reactive oxygen species generation and TNF-α gene expression. Finally, hesperidin treatment improved electrophysiological function, measured with visual evoked potential, and visual function, measured with optomotry. Thus, we found that hesperidin suppressed a number of cytotoxic factors associated with NMDA-induced cell death signaling, such as oxidative stress, over-activation of calpain, and inflammation, thereby protecting the RGCs in mice. Therefore, hesperidin may have potential as a therapeutic supplement for protecting the retina against the damage associated with excitotoxic injury, such as occurs in glaucoma and diabetic retinopathy.
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Affiliation(s)
- Shigeto Maekawa
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Kota Sato
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Kosuke Fujita
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Reiko Daigaku
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Hiroshi Tawarayama
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Namie Murayama
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Satoru Moritoh
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Takeshi Yabana
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Yukihiro Shiga
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Kazuko Omodaka
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Kazuichi Maruyama
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Koji M Nishiguchi
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan
| | - Toru Nakazawa
- Department of Ophthalmology and Visual Science, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan.
- Department of Ophthalmic Imaging and Information Analytics, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan.
- Department of Retinal Disease Control, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan.
- Department of Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, 980-8574, Japan.
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Zhang H, Chang L, Zhang H, Nie J, Zhang Z, Yang X, Vuong AM, Wang Z, Chen A, Niu Q. Calpain-2/p35-p25/Cdk5 pathway is involved in the neuronal apoptosis induced by polybrominated diphenyl ether-153. Toxicol Lett 2017; 277:41-53. [PMID: 28559121 DOI: 10.1016/j.toxlet.2017.05.027] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Revised: 05/18/2017] [Accepted: 05/25/2017] [Indexed: 02/03/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) have been demonstrated to induce neurotoxicity in experimental rats and mice, with neuronal apoptosis as one of the major mechanisms, however, the mechanisms underlying PBDEs-induced neuronal apoptosis remain unclear. In this study, we aimed to investigate the role of calpain/p35-p25/Cdk5 pathway in BDE-153-induced neuronal apoptosis in the hippocampus and primary neurons in rats. Results showed that compared to the controls, neuronal apoptosis was significantly increased in vivo and ex vivo, as manifested by the increased hippocampus TUNEL-positive cell rates, apoptotic neurons in Hoechst and AO/EB staining, and the increased LDH activity and percentage of Annexin V-positive cells in rat hippocampus and primary neurons. Calpain activity was significantly increased in all the BDE-153-treated groups in vivo and ex vivo when compared to non-treatment controls. In addition, we showed that calpain-2 accounted for the calpain activation instead of calpain-1, as demonstrated by the up-regulated mRNA and protein expressions in calpain-2 but not calpain-1. Activated calpain truncated p35 into p25, which resulted in the p25/Cdk5 formation and activation. Calpain inhibitor PD150606 or p25/Cdk5 inhibitor Roscovitine relieved neuronal apoptosis mainly via inhibiting the p25/Cdk5 activation. Overall, the findings suggested that calpain-2/p35-p25/Cdk5 pathway was involved in BDE-153-induced neuronal apoptosis, which provides novel insight into the mechanisms of PBDE neurotoxicity.
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Affiliation(s)
- Hongmei Zhang
- Department of Environmental Health, Shanxi Medical University, Taiyuan 030001, China.
| | - Lijun Chang
- Department of Environmental Health, Shanxi Medical University, Taiyuan 030001, China
| | - Huajun Zhang
- Department of Environmental Health, Shanxi Medical University, Taiyuan 030001, China
| | - Jisheng Nie
- Department of Occupational Health, Shanxi Medical University, Taiyuan 030001, China
| | - Zhihong Zhang
- Department of Environmental Health, Shanxi Medical University, Taiyuan 030001, China
| | - Xiaorong Yang
- Department of Physiology, Shanxi Medical University, Taiyuan 030001, China
| | - Ann M Vuong
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Zemin Wang
- Department of Environmental Health, Indiana University School of Public Health, Bloomington, IN 47408, USA
| | - Aimin Chen
- Department of Environmental Health, University of Cincinnati College of Medicine, Cincinnati, OH, USA
| | - Qiao Niu
- Department of Occupational Health, Shanxi Medical University, Taiyuan 030001, China
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20
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Yamamoto K, Sato K, Yukita M, Yasuda M, Omodaka K, Ryu M, Fujita K, Nishiguchi KM, Machida S, Nakazawa T. The neuroprotective effect of latanoprost acts via klotho-mediated suppression of calpain activation after optic nerve transection. J Neurochem 2017; 140:495-508. [PMID: 27859240 PMCID: PMC5299490 DOI: 10.1111/jnc.13902] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2016] [Revised: 11/08/2016] [Accepted: 11/10/2016] [Indexed: 12/15/2022]
Abstract
Latanoprost was first developed for use in glaucoma therapy as an ocular hypotensive agent targeting the prostaglandin F2α (FP) receptor. Subsequently, latanoprost showed a neuroprotective effect, an additional pharmacological action. However, although it is well-known that latanoprost exerts an ocular hypotensive effect via the FP receptor, it is not known whether this is also true of its neuroprotective effect. Klotho was firstly identified as the gene linked to the suppression of aging phenotype: the defect of klotho gene in mice results aging phenotype such as hypokinesis, arteriosclerosis, and short lifespan. After that, the function of klotho was also reported to maintain calcium homeostasis and to exert a neuroprotective effect in various models of neurodegenerative disease. However, the function of klotho in eyes including retina is still poorly understood. Here, we show that klotho is a key factor underlying the neuroprotective effect of latanoprost during post-axotomy retinal ganglion cell (RGC) degeneration. Importantly, a quantitative RT-PCR gene expression analysis of klotho in sorted rat retinal cells revealed that the highest expression level of klotho in the retina was in the RGCs. Latanoprost acid, the biologically active form of latanoprost, inhibits post-traumatic calpain activation and concomitantly facilitates the expression and shedding of klotho in axotomized RGCs. This expression profile is a good match with the localization, not of the FP receptor, but of organic anion transporting polypeptide 2B1, known as a prostaglandin transporter, in the ocular tissue. Furthermore, an organic anion transporting polypeptide 2B1 inhibitor suppressed latanoprost acid-mediated klotho shedding ex vivo, whereas an FP receptor antagonist did not. The klotho fragments shed from the RGCs reduced the intracellular level of reactive oxygen species, and a specific klotho inhibitor accelerated and increased RGC death after axotomy. We conclude that the shed klotho fragments might contribute to the attenuation of axonal injury-induced calpain activation and oxidative stress, thereby protecting RGCs from post-traumatic neuronal degeneration.
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Affiliation(s)
- Kotaro Yamamoto
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
| | - Kota Sato
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
- Department of Ophthalmic Imaging and Information AnalyticsTohoku University Graduate School of MedicineMiyagiJapan
| | - Masayoshi Yukita
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
| | - Masayuki Yasuda
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
| | - Kazuko Omodaka
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
- Department of Ophthalmic Imaging and Information AnalyticsTohoku University Graduate School of MedicineMiyagiJapan
| | - Morin Ryu
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
| | - Kosuke Fujita
- Department of Retinal Disease ControlTohoku University Graduate School of MedicineMiyagiJapan
| | - Koji M. Nishiguchi
- Department of Advanced Ophthalmic MedicineTohoku University Graduate School of MedicineMiyagiJapan
| | - Shigeki Machida
- Department of OphthalmologyDokkyo Medical University Koshigaya HospitalSaitamaJapan
- Department of OphthalmologyIwate Medical University School of MedicineIwateJapan
| | - Toru Nakazawa
- Department of OphthalmologyTohoku University Graduate School of MedicineMiyagiJapan
- Department of Ophthalmic Imaging and Information AnalyticsTohoku University Graduate School of MedicineMiyagiJapan
- Department of Retinal Disease ControlTohoku University Graduate School of MedicineMiyagiJapan
- Department of Advanced Ophthalmic MedicineTohoku University Graduate School of MedicineMiyagiJapan
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W. Smith A, K. Ray S, Das A, Nozaki K, Rohrer B, L. Banik N. Calpain inhibition as a possible new therapeutic target in multiple sclerosis. AIMS MOLECULAR SCIENCE 2017. [DOI: 10.3934/molsci.2017.4.446] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Himori N, Kunikata H, Kawasaki R, Shiga Y, Omodaka K, Takahashi H, Miyata T, Nakazawa T. The association between skin autofluorescence and mean deviation in patients with open-angle glaucoma. Br J Ophthalmol 2016; 101:233-238. [DOI: 10.1136/bjophthalmol-2016-309504] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2016] [Revised: 11/16/2016] [Accepted: 11/19/2016] [Indexed: 01/12/2023]
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Ozaki T, Yamashita T, Tomita H, Sugano E, Ishiguro SI. The protection of rat retinal ganglion cells from ischemia/reperfusion injury by the inhibitory peptide of mitochondrial μ-calpain. Biochem Biophys Res Commun 2016; 478:1700-5. [PMID: 27596965 DOI: 10.1016/j.bbrc.2016.09.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2016] [Accepted: 09/01/2016] [Indexed: 11/16/2022]
Abstract
Intracellular Ca(2+)-dependent cysteine proteases such as calpains have been suggested as critical factors in retinal ganglion cell (RGC) death. However, it is unknown whether mitochondrial calpains are involved in RGC death. The purpose of the present study was to determine whether the inhibition of mitochondrial μ-calpain activity protects against RGC death during ischemia/reperfusion (I/R) injury. This study used a well-established rat model of experimental acute glaucoma involving I/R injury. A specific peptide inhibitor of mitochondrial μ-calpain, Tat-μCL, was topically applied to rats via eye drops three times a day for 5 days after I/R. RGC death was determined by the terminal deoxynucleotidyl transferase dUTP nick end labeling assay. The truncation of apoptosis-inducing factor (AIF) was determined by western blot analyses. Retinal morphology was determined after staining with hematoxyline and eosin. In addition, the number of Fluoro Gold-labeled RGCs in flat-mounted retinas was used to determine the percentage of surviving RGCs after I/R injury. After 1 day of I/R, RGC death was observed in the ganglion cell layer. Treatment with Tat-μCL eye drops significantly prevented the death of RGCs and the truncation of AIF. After 5 days of I/R, RGC death decreased by approximately 40%. However, Tat-μCL significantly inhibited the decrease in the retinal sections and flat-mounted retinas. The results suggested that mitochondrial μ-calpain is associated with RGC death during I/R injury via truncation of AIF. In addition, the inhibition of mitochondrial μ-calpain activity by Tat-μCL had a neuroprotective effect against I/R-induced RGC death.
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Affiliation(s)
- Taku Ozaki
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Japan; Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki, Japan.
| | - Tetsuro Yamashita
- Department of Biological Chemistry, Faculty of Agriculture, Iwate University, Morioka, Japan
| | - Hiroshi Tomita
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Japan
| | - Eriko Sugano
- Department of Chemistry and Biological Sciences, Faculty of Science and Engineering, Iwate University, Morioka, Japan
| | - Sei-Ichi Ishiguro
- Department of Biochemistry and Molecular Biology, Faculty of Agriculture and Life Science, Hirosaki University, Hirosaki, Japan; Department of Ophthalmology, Tohoku University Graduate School of Medicine, Miyagi, Japan
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Zhao J, Wang S, Zhong W, Yang B, Sun L, Zheng Y. Oxidative stress in the trabecular meshwork (Review). Int J Mol Med 2016; 38:995-1002. [PMID: 27572245 DOI: 10.3892/ijmm.2016.2714] [Citation(s) in RCA: 60] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 08/11/2016] [Indexed: 11/06/2022] Open
Abstract
Glaucoma is the second leading cause of blindness worldwide and elevated intraocular pressure (IOP) is the most important risk factor. High IOP usually occurs as a result of an increase in aqueous humor outflow resistance at the trabecular meshwork (TM). An abnormal TM contributes to the development of glaucoma. Oxidative stress and vascular damage are considered two major cellular factors that lead to alterations in the TM. In this review, we discuss the findings related to oxidative damage to the TM, including the sources of oxidative stress in the TM such as the mitochondria, peroxisomes, endoplasmic reticulum, membrane, cytosol and exogenous factors. We also discuss antioxidants and clinical studies related to protection against oxidative stress in the TM. Although many questions remain unanswered, it is becoming increasingly clear that oxidative stress-induced damage to the TM is related to glaucoma. This may inspire new studies to find better and more stable antioxidants, and better models with which to elucidate the mechanisms involved, and to determine whether in vitro findings translate into in vivo observations. The regulation of the oxidative/redox balance may be the ultimate target for protecting the TM from oxidative stress and preventing glaucoma.
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Affiliation(s)
- Jing Zhao
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
| | - Shuang Wang
- Department of Ophthalmology, China-Japan Union Hospital, Jilin University, Changchun, Jilin 130031, P.R. China
| | - Wei Zhong
- Department of Ophthalmology, China-Japan Union Hospital, Jilin University, Changchun, Jilin 130031, P.R. China
| | - Ben Yang
- Department of Ophthalmology, China-Japan Union Hospital, Jilin University, Changchun, Jilin 130031, P.R. China
| | - Lixia Sun
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
| | - Yajuan Zheng
- Department of Ophthalmology, The Second Hospital of Jilin University, Changchun, Jilin 130041, P.R. China
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25
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Association between systemic oxidative stress and visual field damage in open-angle glaucoma. Sci Rep 2016; 6:25792. [PMID: 27165400 PMCID: PMC4863173 DOI: 10.1038/srep25792] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2016] [Accepted: 04/22/2016] [Indexed: 01/04/2023] Open
Abstract
Local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage may be involved in the pathogenesis of glaucoma. We reported previously that a lower level of systemic antioxidative capacity is associated with IOP elevation in open-angle glaucoma (OAG). We assessed the correlation between the visual field sensitivity value, i.e., mean deviation (MD), and systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in 202 patients with glaucoma. Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured using the diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free-radical analyzer. Univariate and multivariate analyses suggested a positive correlation between MD and BAP (R = 0.005 and P = 0.0442 by a multiple regression model adjusted for seven demographic parameters), but no significant associations between the MD and the dROM (R = 0.002 and P = 0.8556) and SH tests (R = −0.001 and P = 0.8280). Use of more antiglaucoma medication and primary OAG rather than normal tension glaucoma also were associated significantly with worse visual field damage. This large and comprehensive assessment of the association between systemic redox status and visual field damage in OAG suggests that lower systemic antioxidant capacity measured by ferric-reducing activity is associated with more severe visual field damage in OAG that partly explained its roles in IOP elevation.
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Abstract
Open-angle glaucoma (OAG) is characterized by optic nerve fiber atrophy and deterioration of the visual field, corresponding to damage to the optic nerve head. Intraocular pressure (IOP) is currently the only evidence-based, treatable risk factor for OAG. However, normal-tension glaucoma, the most common type of OAG in Asia, is a type of glaucoma with an unclear pathogenesis. Glaucoma is suspected to be a multifactorial disease with IOP-dependent and IOP-independent risk factors, including decreased ocular blood flow (OBF), oxidative stress, decreased axoplasmic flow, and genetic background. A number of epidemiological studies have generated strong evidence that OBF may be an especially important risk factor for the progression of glaucoma. Recent innovations in laser speckle flowgraphy and optical coherence tomography-based angiography have allowed us to noninvasively monitor changes in the microcirculation of the optic nerve head with high reproducibility. Laser speckle flowgraphy-derived measurement parameters include mean blur rate and pulse wave form parameters, whereas the main optical coherence tomography angiography-derived parameter is the vessel index. Decreases in these parameters are associated with the severity of glaucomatous damage, and changes are detectible even in the earliest, preperimetric stage of glaucoma. In the future, OBF analysis may improve significantly because of continuing progress in the development of the relevant instruments. This review will summarize possible connections between systemic and OBF abnormalities and OAG, describe the scientific rationale for these connections, and discuss their potential implications. Thus, this review will summarize the role of OBF in glaucoma pathogenesis and discuss the wide range of IOP-independent risk factors.
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Affiliation(s)
- Toru Nakazawa
- From the Department of Ophthalmology, Retinal Disease Control, Ophthalmology, and Advanced Ophthalmic Medicine, Tohoku University Graduate School of Medicine, Sendai, Japan
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27
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Correlation between Systemic Oxidative Stress and Intraocular Pressure Level. PLoS One 2015; 10:e0133582. [PMID: 26186651 PMCID: PMC4506090 DOI: 10.1371/journal.pone.0133582] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2015] [Accepted: 06/29/2015] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND The involvement of local and systemic oxidative stress in intraocular pressure (IOP) elevation and optic nerve damage has been hypothesized in the pathogenesis of glaucoma. We reported previously that the level of systemic antioxidative capacity is lower in patients with open-angle glaucoma than controls without glaucoma. Here, we assessed the correlation between IOP and systemic levels of prooxidants and antioxidants by analyzing the blood biochemistry in patients with glaucoma. METHODS Peripheral blood samples were collected from Japanese patients with primary open-angle glaucoma (n = 206), exfoliation syndrome (n = 199), and controls (n = 126). Serum levels of lipid peroxides, ferric-reducing activity, and thiol antioxidant activity were measured by diacron reactive oxygen metabolite (dROM), biological antioxidant potential (BAP), and sulfhydryl (SH) tests, respectively, using a free radical analyzer. To test the possible effect of oxidative stress on IOP levels, the patients were classified into one of four groups (Q1, Q2, Q3, and Q4, with Q1 having the lowest IOP) based on the quartile value of IOP. For this classification, the known highest IOP value in both the right and left eyes was regarded as each subject's IOP. For comparisons among the IOP groups, the differences were calculated using one-way analysis of variance followed by post-hoc unpaired t-tests. To adjust for differences in demographic characteristic distributions, the dROM, BAP, and SH test values were compared among the IOP groups using multiple logistic regression analysis; the odds ratio (OR) of each variable was calculated with the Q1 group as the reference. RESULTS The dROM and the SH levels did not differ significantly (p = 0.6704 and p = 0.6376, respectively) among the four IOP groups. The BAP levels differed significantly (p = 0.0115) among the four IOP groups; the value was significantly lower in the Q4 group (1,932 μmol/L) compared with the Q1 (2,023 μmol/L, p = 0.0042) and Q2 (2,003 μmol/L, p = 0.0302) groups and significantly lower in the Q3 group (1,948 μmol/L) than the Q1 (p = 0.0174) group. After adjustment for differences in various demographic characteristics, lower BAP values were significantly associated with the classification into higher IOP groups (Q3 group, p = 0.0261 and OR = 0.06/range; Q4 group, p = 0.0018 and OR = 0.04/range). The dROM and SH values did not reach significance in any comparisons. CONCLUSIONS Lower systemic antioxidant capacity measured by ferric-reducing activity is involved in the pathogenesis of open-angle glaucoma via its roles in IOP elevation.
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Nuschke AC, Farrell SR, Levesque JM, Chauhan BC. Assessment of retinal ganglion cell damage in glaucomatous optic neuropathy: Axon transport, injury and soma loss. Exp Eye Res 2015; 141:111-24. [PMID: 26070986 DOI: 10.1016/j.exer.2015.06.006] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2015] [Revised: 06/01/2015] [Accepted: 06/06/2015] [Indexed: 02/07/2023]
Abstract
Glaucoma is a disease characterized by progressive axonal pathology and death of retinal ganglion cells (RGCs), which causes structural changes in the optic nerve head and irreversible vision loss. Several experimental models of glaucomatous optic neuropathy (GON) have been developed, primarily in non-human primates and, more recently and commonly, in rodents. These models provide important research tools to study the mechanisms underlying glaucomatous damage. Moreover, experimental GON provides the ability to quantify and monitor risk factors leading to RGC loss such as the level of intraocular pressure, axonal health and the RGC population. Using these experimental models we are able to gain a better understanding of GON, which allows for the development of potential neuroprotective strategies. Here we review the advantages and disadvantages of the relevant and most often utilized methods for evaluating axonal degeneration and RGC loss in GON. Axonal pathology in GON includes functional disruption of axonal transport (AT) and structural degeneration. Horseradish peroxidase (HRP), rhodamine-B-isothiocyanate (RITC) and cholera toxin-B (CTB) fluorescent conjugates have proven to be effective reporters of AT. Also, immunohistochemistry (IHC) for endogenous AT-associated proteins is often used as an indicator of AT function. Similarly, structural degeneration of axons in GON can be investigated via changes in the activity and expression of key axonal enzymes and structural proteins. Assessment of axonal degeneration can be measured by direct quantification of axons, qualitative grading, or a combination of both methods. RGC loss is the most frequently quantified variable in studies of experimental GON. Retrograde tracers can be used to quantify RGC populations in rodents via application to the superior colliculus (SC). In addition, in situ IHC for RGC-specific proteins is a common method of RGC quantification used in many studies. Recently, transgenic mouse models that express fluorescent proteins under the Thy-1 promoter have been examined for their potential to provide specific and selective labeling of RGCs for the study of GON. While these methods represent important advances in assessing the structural and functional integrity of RGCs, each has its advantages and disadvantages; together they provide an extensive toolbox for the study of GON.
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Affiliation(s)
- Andrea C Nuschke
- Retina and Optic Nerve Research Laboratory, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Spring R Farrell
- Retina and Optic Nerve Research Laboratory, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Medical Neuroscience, Dalhousie University, Halifax, Nova Scotia, Canada; Capital District Health Authority, Halifax, Nova Scotia, Canada
| | - Julie M Levesque
- Retina and Optic Nerve Research Laboratory, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada
| | - Balwantray C Chauhan
- Retina and Optic Nerve Research Laboratory, Dalhousie University, Halifax, Nova Scotia, Canada; Department of Physiology and Biophysics, Dalhousie University, Halifax, Nova Scotia, Canada; Capital District Health Authority, Halifax, Nova Scotia, Canada; Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Nova Scotia, Canada.
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