1
|
Vázquez-Meza H, Vilchis-Landeros MM, Vázquez-Carrada M, Uribe-Ramírez D, Matuz-Mares D. Cellular Compartmentalization, Glutathione Transport and Its Relevance in Some Pathologies. Antioxidants (Basel) 2023; 12:antiox12040834. [PMID: 37107209 PMCID: PMC10135322 DOI: 10.3390/antiox12040834] [Citation(s) in RCA: 18] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2022] [Revised: 03/24/2023] [Accepted: 03/27/2023] [Indexed: 03/31/2023] Open
Abstract
Reduced glutathione (GSH) is the most abundant non-protein endogenous thiol. It is a ubiquitous molecule produced in most organs, but its synthesis is predominantly in the liver, the tissue in charge of storing and distributing it. GSH is involved in the detoxification of free radicals, peroxides and xenobiotics (drugs, pollutants, carcinogens, etc.), protects biological membranes from lipid peroxidation, and is an important regulator of cell homeostasis, since it participates in signaling redox, regulation of the synthesis and degradation of proteins (S-glutathionylation), signal transduction, various apoptotic processes, gene expression, cell proliferation, DNA and RNA synthesis, etc. GSH transport is a vital step in cellular homeostasis supported by the liver through providing extrahepatic organs (such as the kidney, lung, intestine, and brain, among others) with the said antioxidant. The wide range of functions within the cell in which glutathione is involved shows that glutathione’s role in cellular homeostasis goes beyond being a simple antioxidant agent; therefore, the importance of this tripeptide needs to be reassessed from a broader metabolic perspective.
Collapse
|
2
|
Du Y, Tong Y, Quan Y, Wang G, Cheng H, Gu S, Jiang JX. Protein kinase A activation alleviates cataract formation via increased gap junction intercellular communication. iScience 2023; 26:106114. [PMID: 36852280 PMCID: PMC9958365 DOI: 10.1016/j.isci.2023.106114] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2022] [Revised: 12/09/2022] [Accepted: 01/28/2023] [Indexed: 02/05/2023] Open
Abstract
Cataract is the leading cause of blindness worldwide. Here, we reported a potential, effective therapeutic mean for cataract prevention and treatment. Gap junction communication, an important mechanism in maintaining lens transparency, is increased by protein kinase A (PKA). We found that PKA activation reduced cataracts induced by oxidative stress, increased gap junctions/hemichannels in connexin (Cx) 50, Cx46 or Cx50 and Cx46 co-expressing cells, and decreased reactive oxygen species (ROS) levels. However, ROS reduction was shown in wild-type, Cx46 and Cx50 knockout, but not in Cx46/Cx50 double KO lens. In addition, PKA activation protects lens fiber cell death induced by oxidative stress via hemichannel-mediated glutathione transport. Connexin deletion increased lens opacity induced by oxidative stress associated with reduction of anti-oxidative stress gene expression. Together, our results suggest that PKA activation through increased connexin channels in lens fiber cell decreases ROS levels and cell death, leading to alleviated cataracts.
Collapse
Affiliation(s)
- Yu Du
- Department of Ophthalmology, Lanzhou University Second Hospital; Second Clinical School, Lanzhou University, Lanzhou, Gansu, 730000, China
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| | - Yuxin Tong
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| | - Yumeng Quan
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
- Department of Ophthalmology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Guangyan Wang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
- Department of Ophthalmology, First Affiliated Hospital of Xi’an Jiaotong University, Xi’an, Shaanxi, China
| | - Hongyun Cheng
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| | - Sumin Gu
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| | - Jean X. Jiang
- Department of Biochemistry and Structural Biology, University of Texas Health Science Center, San Antonio, TX 78229-3900, USA
| |
Collapse
|
3
|
Martis RM, Li B, Donaldson PJ, Lim JCH. Early Onset of Age-Related Cataracts in Cystine/Glutamate Antiporter Knockout Mice. Invest Ophthalmol Vis Sci 2021; 62:23. [PMID: 34156426 PMCID: PMC8237109 DOI: 10.1167/iovs.62.7.23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Purpose The purpose of this study was to determine the importance of the xCT is a subunit. The cystine/glutamate antiporter is actually system xc-xCT subunit of the cystine/glutamate antiporter in maintaining redox balance by investigating the effects of the loss of xCT on lens transparency and cystine/cysteine balance in the aqueous humour. Methods C57Bl/6 wild-type and xCT knockout mice at five age groups (6 weeks to 12 months) were used. Lens transparency was examined using a slit-lamp and morphological changes visualized by immunolabelling and confocal microscopy. Quantification of glutathione in lenses and cysteine and cystine levels in the aqueous was conducted by liquid chromatography tandem mass spectrometry (LC-MS/MS). Results Slit-lamp examinations revealed that 3-month-old wild-type mice and xCT knockout mice lenses exhibited an anterior localized cataract. The frequency of this cataract significantly increased in the knockout mice compared to the wild-type mice. Morphological studies revealed a localized swelling of the lens fiber cells at the anterior pole. Glutathione levels in whole lenses were similar between wild-type and knockout mice. However, glutathione levels were significantly decreased at 3 months in the knockout mice in the lens epithelium compared to the wild-type mice. Aqueous cysteine levels remained similar between wild-type and knockout mice at all age groups, whereas cystine levels were significantly increased in 3-, 9-, and 12-month-old knockout mice compared to wild-type mice. Conclusions Loss of xCT resulted in the depletion of glutathione in the epithelium and an oxidative shift in the cysteine/cystine ratio of the aqueous. Together, these oxidative changes may contribute to the accelerated development of an anterior cataract in knockout mice, which appears to be a normal feature of aging in wild-type mice.
Collapse
Affiliation(s)
- Renita Maria Martis
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Bo Li
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Paul James Donaldson
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Julie Ching-Hsia Lim
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, New Zealand.,New Zealand National Eye Centre, University of Auckland, Auckland, New Zealand
| |
Collapse
|
4
|
Li B, Kim JY, Martis RM, Donaldson PJ, Lim JC. Characterisation of Glutathione Export from Human Donor Lenses. Transl Vis Sci Technol 2020; 9:37. [PMID: 32855883 PMCID: PMC7422761 DOI: 10.1167/tvst.9.8.37] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2020] [Accepted: 06/03/2020] [Indexed: 01/13/2023] Open
Abstract
Purpose To investigate whether human donor lenses are capable of exporting reduced glutathione. Methods Human lenses of varying ages were cultured in artificial aqueous humor for 1 hour under hypoxic conditions to mimic the physiologic environment and reduced glutathione (GSH) and oxidized glutathione (GSSG) levels measured in the media and in the lens. Results Human donor lenses released both GSH and GSSG into the media. Donor lenses cultured in the presence of acivicin, a γ-glutamyltranspeptidase inhibitor, exhibited a significant increase in GSSG levels (P < 0.05), indicating that GSSG undergoes degradation into its constituent amino acids. Screening of GSH/GSSG efflux transporters revealed Mrp1, Mrp4, and Mrp5 to be present at the transcript level, but only Mrp5 was expressed at the protein level. Blocking Mrp5 function with the Mrp inhibitor MK571 led to a significant decrease in GSSG efflux (P < 0.05), indicating that Mrp5 is likely to be involved in mediating GSSG efflux. Measurements of efflux from the anterior and posterior surface of the lens revealed that GSH and GSSG efflux occurs at both surfaces but predominantly at the anterior surface. Conclusions Human lenses export GSH and GSSG into the surrounding ocular humors, which can be recycled by the lens to maintain intracellular GSH homeostasis or used by neighboring tissues to maintain GSH levels. Translational Relevance Early removal of a clear lens, as occurs to treat myopia and presbyopia, would eliminate this GSH reservoir and reduce the supply of GSH to other tissues, which, over time, may have clinical implications for the progression of other ocular diseases associated with oxidative stress.
Collapse
Affiliation(s)
- Bo Li
- Department of Physiology, University of Auckland, New Zealand
- New Zealand-National Eye Centre, University of Auckland, New Zealand
- School of Medical Sciences, University of Auckland, New Zealand
| | - Ji-Youn Kim
- Department of Physiology, University of Auckland, New Zealand
- New Zealand-National Eye Centre, University of Auckland, New Zealand
- School of Medical Sciences, University of Auckland, New Zealand
| | - Renita M. Martis
- Department of Physiology, University of Auckland, New Zealand
- New Zealand-National Eye Centre, University of Auckland, New Zealand
- School of Medical Sciences, University of Auckland, New Zealand
| | - Paul J. Donaldson
- Department of Physiology, University of Auckland, New Zealand
- New Zealand-National Eye Centre, University of Auckland, New Zealand
- School of Medical Sciences, University of Auckland, New Zealand
| | - Julie C. Lim
- Department of Physiology, University of Auckland, New Zealand
- New Zealand-National Eye Centre, University of Auckland, New Zealand
- School of Medical Sciences, University of Auckland, New Zealand
| |
Collapse
|
5
|
Identification, Expression, and Roles of the Cystine/Glutamate Antiporter in Ocular Tissues. OXIDATIVE MEDICINE AND CELLULAR LONGEVITY 2020; 2020:4594606. [PMID: 32655769 PMCID: PMC7320271 DOI: 10.1155/2020/4594606] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/15/2020] [Accepted: 05/21/2020] [Indexed: 01/21/2023]
Abstract
The cystine/glutamate antiporter (system x c -) is composed of a heavy chain subunit 4F2hc linked by a disulphide bond to a light chain xCT, which exchanges extracellular cystine, the disulphide form of the amino acid cysteine, for intracellular glutamate. In vitro research in the brain, kidney, and liver have shown this antiporter to play a role in minimising oxidative stress by providing a source of intracellular cysteine for the synthesis of the antioxidant glutathione. In vivo studies using the xCT knockout mouse revealed that the plasma cystine/cysteine redox couple was tilted to a more oxidative state demonstrating system xc - to also play a role in maintaining extracellular redox balance by driving a cystine/cysteine redox cycle. In addition, through import of cystine, system xc - also serves to export glutamate into the extracellular space which may influence neurotransmission and glutamate signalling in neural tissues. While changes to system xc - function has been linked to cancer and neurodegenerative disease, there is limited research on the roles of system xc - in the different tissues of the eye, and links between the antiporter, aging, and ocular disease. Hence, this review seeks to consolidate research on system xc - in the cornea, lens, retina, and ocular humours conducted across several species to shed light on the in vitro and in vivo roles of xCT in the eye and highlight the utility of the xCT knockout mouse as a tool to investigate the contribution of xCT to age-related ocular diseases.
Collapse
|
6
|
Martis RM, Donaldson PJ, Li B, Middleditch M, Kallingappa PK, Lim JC. Mapping of the cystine-glutamate exchanger in the mouse eye: a role for xCT in controlling extracellular redox balance. Histochem Cell Biol 2019; 152:293-310. [PMID: 31396687 DOI: 10.1007/s00418-019-01805-4] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/24/2019] [Indexed: 12/13/2022]
Abstract
The cystine-glutamate exchanger (system xc-) is responsible for the exchange of extracellular cystine for intracellular glutamate. In this study, we mapped the expression of xCT, the light chain subunit of system xc- in the different tissues of 3-6-week-old mouse (C57BL/6J) eye and have used an xCT knockout mouse to verify labelling specificity. Moreover, using the xCT knockout mouse, we investigated whether xCT was involved in maintaining extracellular redox balance in the eye. xCT transcript and protein were present in the cornea, lens and retina of wild-type mice, but not knockout mice. xCT was localised to the corneal epithelium, and the lens epithelium and cortical fibre cells but was absent in the iris. xCT localisation could not be determined in the ciliary body or retina, since xCT labelling was also detected in the knockout indicating a lack of specificity of the xCT antibody in tissues of a neural origin. Intracellular cysteine and cystine concentrations were similar in the wild-type and xCT knockout mouse for the cornea, lens, and retina. While extracellular cysteine levels were similar between the plasma, aqueous humour, and vitreous humour of the wild-type and xCT knockout mouse, extracellular cystine levels in the plasma and aqueous were significantly elevated in the xCT knockout mouse relative to the wild type. This suggests that loss of xCT results in an increased oxidative environment, particularly within the anterior chamber of the eye in which the aqueous humour resides. How this oxidative shift impacts ocular tissues that interface with the aqueous humour over time will be the focus of future work.
Collapse
Affiliation(s)
- Renita M Martis
- Department of Physiology, School of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand.,School of Medical Sciences, University of Auckland, Auckland, New Zealand.,NZ National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Paul J Donaldson
- Department of Physiology, School of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand.,School of Medical Sciences, University of Auckland, Auckland, New Zealand.,NZ National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Bo Li
- Department of Physiology, School of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand.,School of Medical Sciences, University of Auckland, Auckland, New Zealand.,NZ National Eye Centre, University of Auckland, Auckland, New Zealand
| | - Martin Middleditch
- School of Biological Sciences, University of Auckland, Auckland, New Zealand
| | - Prasanna K Kallingappa
- Department of Molecular Medicine and Pathology, University of Auckland, Auckland, New Zealand.,School of Medical Sciences, University of Auckland, Auckland, New Zealand
| | - Julie C Lim
- Department of Physiology, School of Medical and Health Sciences, University of Auckland, Auckland, 1023, New Zealand. .,School of Medical Sciences, University of Auckland, Auckland, New Zealand. .,NZ National Eye Centre, University of Auckland, Auckland, New Zealand.
| |
Collapse
|
7
|
Umapathy A, Li B, Donaldson PJ, Lim JC. Functional characterisation of glutathione export from the rat lens. Exp Eye Res 2018; 166:151-159. [DOI: 10.1016/j.exer.2017.10.010] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Revised: 09/19/2017] [Accepted: 10/10/2017] [Indexed: 02/08/2023]
|
8
|
Fan X, Monnier VM, Whitson J. Lens glutathione homeostasis: Discrepancies and gaps in knowledge standing in the way of novel therapeutic approaches. Exp Eye Res 2016; 156:103-111. [PMID: 27373973 DOI: 10.1016/j.exer.2016.06.018] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/10/2016] [Accepted: 06/25/2016] [Indexed: 01/18/2023]
Abstract
Cataract is the major cause of blindness worldwide. The WHO has estimated around 20 million people have bilateral blindness from cataract, and that number is expected to reach 50 million in 2050. The cataract surgery is currently the main treatment approach, though often associated with complications, such as Posterior Capsule Opacification (PCO)-also known as secondary cataract. The lens is an avascular ocular structure equipped with an unusually high level of glutathione (GSH), which plays a vital role in maintaining lens transparency by regulating lenticular redox state. The lens epithelium and outer cortex are thought to be responsible for providing the majority of lens GSH via GSH de novo synthesis, assisted by a continuous supply of constituent amino acids from the aqueous humor, as well as extracellular GSH recycling from the gamma-glutamyl cycle. However, when de novo synthesis is impaired, in the presence of low GSH levels, as in the aging human lens, compensatory mechanisms exist, suggesting that the lens is able to uptake GSH from the surrounding ocular tissues. However, these uptake mechanisms, and the GSH source and its origin, are largely unknown. The lens nucleus does not have the ability to synthesize its own GSH and fully relies on transport from the outer cortex by yet unknown mechanisms. Understanding how aging reduces GSH levels, particularly in the lens nucleus, how it is associated with age-related nuclear cataract (ARNC), and how the lens compensates for GSH loss via external uptake should be a major research priority. The intent of this review, which is dedicated to the memory of David C. Beebe, is to summarize our current understanding of lens GSH homeostasis and highlight discrepancies and gaps in knowledge that stand in the way of pharmacologically minimizing the impact of declining GSH content in the prevention of age-related cataract.
Collapse
Affiliation(s)
- Xingjun Fan
- Department of Pathology, Case Western Reserve University, USA.
| | - Vincent M Monnier
- Department of Pathology, Case Western Reserve University, USA; Department of Biochemistry, Case Western Reserve University, USA
| | - Jeremy Whitson
- Department of Pathology, Case Western Reserve University, USA
| |
Collapse
|
9
|
Lim JC, Umapathy A, Grey AC, Vaghefi E, Donaldson PJ. Novel roles for the lens in preserving overall ocular health. Exp Eye Res 2016; 156:117-123. [PMID: 27282996 DOI: 10.1016/j.exer.2016.05.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2016] [Revised: 05/12/2016] [Accepted: 05/29/2016] [Indexed: 12/11/2022]
Abstract
Outside the traditional roles of the lens as an important refractive element and a UV filter, it was David Beebe's group that first demonstrated that the lens acts an oxygen sink that protects the tissues of the anterior segment of the eye from oxygen or oxygen metabolites. In this review, we follow on from this work, and present new evidence from our laboratory to demonstrate that the lens serves as a reservoir for the release of the antioxidant glutathione (GSH) into the aqueous humor to provide a source of GSH and/or its precursor amino acids to nearby tissues that interface with the aqueous humor, or to remove toxic metabolites from the eye via the aqueous outflow pathway. In addition to GSH release, our laboratory and others have shown that ATP is released from the lens under hyposmotic conditions to activate purinergic signalling pathways in an autocrine manner to alter lens function. In this review, we raise the idea that ATP and/or its subsequent degradation product adenosine may exert a paracrine function and influence purinergic signalling systems in other tissues to alter aqueous humor outflow. These new secondary roles indicate that the lens is not just a passive optical element, but a highly dynamic and active tissue that interacts with its neighbouring tissues, through modifying the environments in which these tissues function. We believe that the lens actively contributes to the ocular environment and as a consequence, removal of the lens would alter the functionality of neighbouring tissues. We speculate that a long term effect of lens removal may be to inadvertently increase the exposure of anterior tissues of the eye to oxidative stress due to elevated oxygen levels and a reduction in the availability of GSH and purinergic signalling molecules in the aqueous humor. Since cataract surgery is now being performed on younger patients due to our increasing diabetic population, over time, we predict these changes may increase the susceptibility of these tissues to oxidative stress and the incidence of subsequent ocular pathologies. If our view of the lens is correct, the actual loss of the biological lens may have longer term consequences for overall ocular health than currently appreciated.
Collapse
Affiliation(s)
- Julie C Lim
- Department of Physiology, University of Auckland, Auckland, New Zealand; School of Medical Sciences, University of Auckland, New Zealand; New Zealand National Eye Centre, University of Auckland, New Zealand.
| | - Ankita Umapathy
- Department of Physiology, University of Auckland, Auckland, New Zealand; School of Medical Sciences, University of Auckland, New Zealand; New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Angus C Grey
- Department of Physiology, University of Auckland, Auckland, New Zealand; School of Medical Sciences, University of Auckland, New Zealand; New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Ehsan Vaghefi
- School of Optometry and Vision Science, University of Auckland, New Zealand; New Zealand National Eye Centre, University of Auckland, New Zealand
| | - Paul J Donaldson
- Department of Physiology, University of Auckland, Auckland, New Zealand; School of Medical Sciences, University of Auckland, New Zealand; New Zealand National Eye Centre, University of Auckland, New Zealand
| |
Collapse
|
10
|
Martínez-González JJ, Guevara-Flores A, Rendón JL, Arenal IPD. Auranofin-induced oxidative stress causes redistribution of the glutathione pool in Taenia crassiceps cysticerci. Mol Biochem Parasitol 2015; 201:16-25. [PMID: 26024834 DOI: 10.1016/j.molbiopara.2015.05.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2014] [Revised: 03/28/2015] [Accepted: 05/06/2015] [Indexed: 12/16/2022]
Abstract
Previously, we have studied the effect of the gold-compound auranofin (AF) on both thioredoxin-glutathione reductasa (TGR) activity and viability of Taenia crassiceps cysticerci. It was demonstrated that micromolar concentrations of AF were high enough to fully inhibit TGR and kill the parasites. In this work, the dynamics of changes in the glutathione pool of T. crassiceps cysticerci following the addition of AF, was analyzed. A dose-dependent decrease in the internal glutathione concentration, concomitant with an increase in ROS production was observed. These changes were simultaneous with the formation of glutathione-protein complexes and the export of glutathione disulfide (GSSG) to the culture medium. Incubation of cysticerci in the presence of both AF and N-acetyl cysteine (NAC) prevents all the above changes, maintaining cysticerci viability. By contrast, the presence of both AF and buthionine sulfoximine (BSO) resulted in a potentiation of the effects of the gold compound, jeopardizing cysticerci viability. These results suggest the lethal effect of AF on T. crassiceps cysticerci, observed at micromolar concentrations, can be explained as a consequence of major changes in the glutathione status, which results in a significant increase in the oxidative stress of the parasites.
Collapse
Affiliation(s)
- J J Martínez-González
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70-159, 04510 Mexico, DF, Mexico
| | - A Guevara-Flores
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70-159, 04510 Mexico, DF, Mexico
| | - J L Rendón
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70-159, 04510 Mexico, DF, Mexico
| | - I P Del Arenal
- Departamento de Bioquímica, Facultad de Medicina, Universidad Nacional Autónoma de México (UNAM), Apartado Postal 70-159, 04510 Mexico, DF, Mexico.
| |
Collapse
|
11
|
Langford MP, Redens TB, Texada DE. Excitatory Amino Acid Transporters, Xc− Antiporter, γ-Glutamyl Transpeptidase, Glutamine Synthetase, and Glutathione in Human Corneal Epithelial Cells. OXIDATIVE STRESS IN APPLIED BASIC RESEARCH AND CLINICAL PRACTICE 2015. [DOI: 10.1007/978-1-4939-1935-2_4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
|
12
|
The Histochem Cell Biol conspectus: the year 2013 in review. Histochem Cell Biol 2014; 141:337-63. [PMID: 24610091 PMCID: PMC7087837 DOI: 10.1007/s00418-014-1207-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/25/2014] [Indexed: 11/29/2022]
Abstract
Herein, we provide a brief synopsis of all manuscripts published in Histochem Cell Biol in the year 2013. For ease of reference, we have divided the manuscripts into the following categories: Advances in Methodologies; Molecules in Health and Disease; Organelles, Subcellular Structures and Compartments; Golgi Apparatus; Intermediate Filaments and Cytoskeleton; Connective Tissue and Extracellular Matrix; Autophagy; Stem Cells; Musculoskeletal System; Respiratory and Cardiovascular Systems; Gastrointestinal Tract; Central Nervous System; Peripheral Nervous System; Excretory Glands; Kidney and Urinary Bladder; and Male and Female Reproductive Systems. We hope that the readership will find this annual journal synopsis of value and serve as a quick, categorized reference guide for “state-of-the-art” manuscripts in the areas of histochemistry, immunohistochemistry, and cell biology.
Collapse
|
13
|
Umapathy A, Donaldson P, Lim J. Antioxidant delivery pathways in the anterior eye. BIOMED RESEARCH INTERNATIONAL 2013; 2013:207250. [PMID: 24187660 PMCID: PMC3804153 DOI: 10.1155/2013/207250] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/02/2013] [Accepted: 08/08/2013] [Indexed: 02/04/2023]
Abstract
Tissues in the anterior segment of the eye are particular vulnerable to oxidative stress. To minimise oxidative stress, ocular tissues utilise a range of antioxidant defence systems which include nonenzymatic and enzymatic antioxidants in combination with repair and chaperone systems. However, as we age our antioxidant defence systems are overwhelmed resulting in increased oxidative stress and damage to tissues of the eye and the onset of various ocular pathologies such as corneal opacities, lens cataracts, and glaucoma. While it is well established that nonenzymatic antioxidants such as ascorbic acid and glutathione are important in protecting ocular tissues from oxidative stress, less is known about the delivery mechanisms used to accumulate these endogenous antioxidants in the different tissues of the eye. This review aims to summarise what is currently known about the antioxidant transport pathways in the anterior eye and how a deeper understanding of these transport systems with respect to ocular physiology could be used to increase antioxidant levels and delay the onset of eye diseases.
Collapse
Affiliation(s)
- Ankita Umapathy
- Department of Optometry and Vision Science, University of Auckland, Auckland 1023, New Zealand
- New Zealand National Eye Centre, University of Auckland, Auckland 1023, New Zealand
| | - Paul Donaldson
- New Zealand National Eye Centre, University of Auckland, Auckland 1023, New Zealand
- School of Medical Sciences, University of Auckland, Auckland 1023, New Zealand
| | - Julie Lim
- Department of Optometry and Vision Science, University of Auckland, Auckland 1023, New Zealand
- New Zealand National Eye Centre, University of Auckland, Auckland 1023, New Zealand
| |
Collapse
|