Do Connexin Mutants Cause Cataracts by Perturbing Glutathione Levels and Redox Metabolism in the Lens?
Abstract
:1. Introduction
2. Materials and Methods
2.1. Animals
2.2. Measurement of Reduced and Oxidized Glutathione (GSH and GSSG)
2.3. Antibodies
2.4. Polyacrylamide Gel Electrophoresis, Immunoblotting, and Silver Staining
2.5. Detection and Quantification of Carbonylated Proteins
2.6. Statistical Analysis
3. Results
3.1. GSH Levels are Not Reduced in Connexin Mutant Lenses
3.2. Enzymes for GSH Production Are Increased in Cx50D47A and Cx46fs380 Lenses
3.3. Oxidation of Glutathione is Greater in Cx50D47A than in Cx46fs380 Lenses
3.4. GSH levels are Decreased and Its Oxidation Is Increased in the Nucleus of Older Cx46fs380 Lenses
3.5. Carbonylation of Lens Proteins Is Increased in Cx50D47A, but Not in Cx46fs380 Lenses
3.6. Cx50D47A and Cx46fs380 Lenses Show Some Increases in High Molecular Weight Proteins
4. Discussion
5. Conclusions
Author Contributions
Funding
Conflicts of Interest
References
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Cx46fs380 | Cx50D47A | |
---|---|---|
Age of Noticeable Cataract | ~2 months homozygotes; ≥4 months heterozygotes | <1 month heterozygotes and homozygotes |
Differentiation | Normal | Impaired |
Lens Size | Normal | Smaller than wild-type |
Severity of Cataract | Less severe compared with Cx50D47A cataracts | Severe |
Age | Genotype | Mean Grey Value (Mean ± S.E.M.) | Number of Sets (n) | |
---|---|---|---|---|
Non-reducing | Reducing | |||
1 month | +/+ | 52.1 ± 6.4 | 57.9 ± 10.0 | 4 |
+/D47A | 52.5 ± 7.0 | 68.4 ± 10.3 | ||
D47A/D47A | 60.0 ± 7.1 | 82.3 ± 10.3 * | ||
2.5 months | +/+ | 35.1 ± 3.3 | 47.5 ± 1.3 | 3 |
+/D47A | 37.3 ± 4.2 | 58.6 ± 0.6 * | ||
D47A/D47A | 64.3 ± 8.3 | 71.2 ± 2.1 * | ||
2.5 months | +/+ | 41.1 ± 5.2 | 64.8 ± 7.0 | 3 |
+/fs380 | 38.0 ± 4.0 | 79.4 ± 3.2 | ||
fs380/fs380 | 42.1 ± 1.9 | 76.4 ± 2.2 | ||
4.5 months | +/+ | 92.5 ± 1.7 | 78.6 ± 5.6 | 3 |
fs380/fs380 | 105.3 ± 3.4 * | 77.9 ± 4.0 |
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Jara, O.; Minogue, P.J.; Berthoud, V.M.; Beyer, E.C. Do Connexin Mutants Cause Cataracts by Perturbing Glutathione Levels and Redox Metabolism in the Lens? Biomolecules 2020, 10, 1418. https://0-doi-org.brum.beds.ac.uk/10.3390/biom10101418
Jara O, Minogue PJ, Berthoud VM, Beyer EC. Do Connexin Mutants Cause Cataracts by Perturbing Glutathione Levels and Redox Metabolism in the Lens? Biomolecules. 2020; 10(10):1418. https://0-doi-org.brum.beds.ac.uk/10.3390/biom10101418
Chicago/Turabian StyleJara, Oscar, Peter J. Minogue, Viviana M. Berthoud, and Eric C. Beyer. 2020. "Do Connexin Mutants Cause Cataracts by Perturbing Glutathione Levels and Redox Metabolism in the Lens?" Biomolecules 10, no. 10: 1418. https://0-doi-org.brum.beds.ac.uk/10.3390/biom10101418