ABC  Vol.4 No.1 , February 2014
N-acetylcysteine amide protects against dexamethasone-induced cataract related changes in cultured rat lenses
ABSTRACT
Glucocorticoids (GCs) are one of the most widely used immunosuppressive and anti-inflammatory agents. However, their long term and systemic use is associated with adverse drug reactions including posterior subcapsular cataracts as one of its ocular complications. Balanced redox state is crucial for maintenance of lens transparency, and a high content of glutathione (GSH) in the lens is believed to play a key role in doing so. Depletion of GSH is implicated in the etiopathogenesis of dexamethasone-induced cataracts and, therefore, the present study was sought to evaluate the efficacy of a novel thiol antioxidant, N-acetylcysteine amide (NACA), in preventing dexamethasone-induced cataractogenesis. Cataract formation was induced by incubation of rat lenses with 5 μM dexamethasone. To assess whether NACA had a significant impact on dexamethasone-induced cataracts, the rat lenses were divided into four groups: 1) control group (Dulbecco’s Modified Eagle Medium (DMEM), 2) dexamethasone group (DMEM with 5 μM dexamethasone), 3) NACA-only group (50 μM NACA solution), and 4) NACA pretreatment group (50 μM NACA for 6 hours followed by 5 μM dexamethasone only for 18 hours). Lenses were cultured for 7 days at 37°C under 5% CO2. Lenses were evaluated daily using a dissecting microscope and photographed and graded for the development of opacity. The rat lenses in both the control and the NACA-only groups were clear, whereas all lenses within the dexamethasone-only group developed well-defined cataracts. Overall observations indicated that NACA inhibits cataract formation by limiting lipid peroxidation and increasing the ratio of GSH/GSSG in lens. Therefore, NACA can be developed into a potential adjunctive therapeutic option for patients undergoing therapy with GCs to inhibit glucocorticoid-induced cataracts.

Cite this paper
Tobwala, S. , Pinarci, E. , Maddirala, Y. and Ercal, N. (2014) N-acetylcysteine amide protects against dexamethasone-induced cataract related changes in cultured rat lenses. Advances in Biological Chemistry, 4, 26-34. doi: 10.4236/abc.2014.41005.
References
[1]   Geley, S., Fiegl, M., Hartmann, B.L. and Kofler, R. (1996) Genes mediating glucocorticoid effects and mechanisms of their regulation. Reviews of Physiology, Biochemistry and Pharmacology, 128, 1-97.

[2]   Reichardt, H.M., Tronche, F., Berger, S., Kellendonk, C. and Schutz, G. (2001) New insights into glucocorticoid and mineralocorticoid signaling: Lessons from gene targeting. Advances in Pharmacology, 47, 1-21.

[3]   Jobling, A.I. and Augusteyn, R.C. (2002) What causes steroid cataracts? A review of steroid-induced posterior subcapsular cataracts. Clinical and Experimental Optometry, 85, 61-75.
http://dx.doi.org/10.1111/j.1444-0938.2002.tb03011.x

[4]   Carnahan, M.C. and Goldstein, D.A. (2000) Ocular complications of topical, periocular, and systemic corticosteroids. Current Opinion in Ophthalmology, 11, 478-483.

[5]   Wang, C., Dawes, L.J., Liu, Y., Wen, L., Lovicu, F.J. and McAvoy, J.W. (2013) Dexamethasone influences FGF-induced responses in lens epithelial explants and promotes the posterior capsule coverage that is a feature of glucocorticoid-induced cataract. Experimental Eye Research, 111, 79-87.
http://dx.doi.org/10.1016/j.exer.2013.03.006

[6]   Urban, R.C. and Cotlier, E. (1986) Corticosteroid-induced cataracts. Survey of Ophthalmology, 31, 102-110.
http://dx.doi.org/10.1016/0039-6257(86)90077-9

[7]   Praveen, M.R., Shah, G.D., Vasavada, A.R., Shah, A.R., Johar K., Gami Y., et al. (2011) Posterior capsule opacification in eyes with steroid-induced cataracts: Comparison of early results. Journal of Cataract & Refractive Surgery, 37, 88-96.
http://dx.doi.org/10.1016/j.jcrs.2010.08.035

[8]   Liu, A. and Manche, E.E. (2011) Bilateral posterior subcapsular cataracts associated with long-term intranasal steroid use. Journal of Cataract & Refractive Surgery, 37, 1555-1558.
http://dx.doi.org/10.1016/j.jcrs.2011.05.020

[9]   Nishigori, H., Lee, J.W., Yamauchi, Y. and Iwatsuru, M. (1986) The alteration of lipid peroxide in glucocorticoid-induced cataract of developing chick embryos and the effect of ascorbic acid. Current Eye Research, 5, 37-40.
http://dx.doi.org/10.3109/02713688608995163

[10]   Anderson, E.I., Wright, D.D. and Spector, A. (1979) The state of sulfhydryl groups in normal and cataractous human lens proteins. II. Cortical and nuclear regions. Experimental Eye Research, 29, 233-243.
http://dx.doi.org/10.1016/0014-4835(79)90004-6

[11]   Lou, M.F., Dickerson, J.E. Jr., Garadi, R. and York, B.M., Jr. (1988) Glutathione depletion in the lens of galactosemic and diabetic rats. Experimental Eye Research, 46, 517-530. http://dx.doi.org/10.1016/S0014-4835(88)80009-5

[12]   Reddy, V.N. (1990) Glutathione and its function in the lens—An overview. Experimental Eye Research, 50, 771-778.
http://dx.doi.org/10.1016/0014-4835(90)90127-G

[13]   Spector, A. (1995) Oxidative stress-induced cataract: Mechanism of action. The FASEB Journal, 9, 1173-1182.

[14]   Taylor, A. and Davies, K.J. (1987) Protein oxidation and loss of protease activity may lead to cataract formation in the aged lens. Free Radical Biology & Medicine, 3, 371-377.
http://dx.doi.org/10.1016/0891-5849(87)90015-3

[15]   Babizhayev M.A. and Costa E.B. (1994) Lipid peroxide and reactive oxygen species generating systems of the crystalline lens. Biochimica et Biophysica Acta, 1225, 326-337. http://dx.doi.org/10.1016/0925-4439(94)90014-0

[16]   Dische, Z. and Zil, H. (1951) Studies on the oxidation of cysteine to cystine in lens proteins during cataract formation. American Journal of Ophthalmology, 34,104-113.

[17]   Kleiman, N.J. and Spector, A. (1993) DNA single strand breaks in human lens epithelial cells from patients with cataract. Current Eye Research, 12, 423-431.
http://dx.doi.org/10.3109/02713689309024624

[18]   Spector, A. and Roy, D. (1978) Disulfide-linked high molecular weight protein associated with human cataract. Proceedings of the National Academy of Sciences of the United States of America, 75, 3244-3248.
http://dx.doi.org/10.1073/pnas.75.7.3244

[19]   Zigler, J.S. Jr., Huang, Q.L. and Du, X.Y. (1989) Oxidative modification of lens crystallins by H2O2 and chelated iron. Free Radical Biology & Medicine, 7, 499-505.
http://dx.doi.org/10.1016/0891-5849(89)90025-7

[20]   Simpanya, M.F., Ansari, R.R., Suh, K.I., Leverenz, V.R. and Giblin, F.J. (2005) Aggregation of lens crystallins in an in vivo hyperbaric oxygen guinea pig model of nuclear cataract: Dynamic light-scattering and HPLC analysis. Investigative Ophthalmology & Visual Science, 46, 4641-4651.
http://dx.doi.org/10.1167/iovs.05-0843

[21]   Zigler, J.S. Jr., Bodaness, R.S., Gery, I. and Kinoshita, J.H. (1983) Effects of lipid peroxidation products on the rat lens in organ culture: A possible mechanism of cataract initiation in retinal degenerative disease. Archives of Biochemistry and Biophysics, 225, 149-156.
http://dx.doi.org/10.1167/iovs.05-0843

[22]   Zigler, J.S. Jr., Gery, I., Kessler, D. and Kinoshita, J.H. (1983) Macrophage mediated damage to rat lenses in culture: A possible model for uveitis-associated cataract. Investigative Ophthalmology & Visual Science, 24, 651-654.

[23]   Goosey, J.D., Tuan, W.M. and Garcia, C.A. (1984) A lipid peroxidative mechanism for posterior subcapsular cataract formation in the rabbit: A possible model for cataract formation in tapetoretinal diseases. Investigative Ophthalmology & Visual Science, 25, 608-612.

[24]   Zigler, J.S. Jr. and Hess, H.H. (1985) Cataracts in the Royal College of Surgeons rat: Evidence for initiation by lipid peroxidation products. Experimental Eye Research, 41, 67-76.
http://dx.doi.org/10.1016/0014-4835(85)90095-8

[25]   Borchman, D., Paterson, C.A. and Delamere, N.A. (1989) Oxidative inhibition of Ca2+-ATPase in the rabbit lens. Investigative Ophthalmology & Visual Science, 30, 1633-1637.

[26]   Kagan V.E. (1988) Lipid peroxidation in biomembranes. CRC Press, Boca Raton, 181.

[27]   Park, J.W. and Floyd, R.A. (1992) Lipid peroxidation products mediate the formation of 8-hydroxydeoxygua-nosine in DNA. Free Radical Biology & Medicine, 12, 245-250. http://dx.doi.org/10.1016/0891-5849(92)90111-S

[28]   Harding, J.J. (1970) Free and protein-bound glutathione in normal and cataractous human lenses. Biochemical Journal, 117, 957-960.

[29]   Linetsky, M., James, H.L. and Ortwerth, B.J. (1999) Spontaneous generation of superoxide anion by human lens proteins and by calf lens proteins ascorbylated in vitro. Experimental Eye Research, 69, 239-248.
http://dx.doi.org/10.1006/exer.1999.0710

[30]   Fu, S., Dean, R., Southan, M. and Truscott, R. (1998) The hydroxyl radical in lens nuclear cataractogenesis. The Journal of Biological Chemistry, 273, 28603-28609.
http://dx.doi.org/10.1074/jbc.273.44.28603

[31]   Rathbun, W.B. and Bovis, M.G. (1986) Activity of glutathione peroxidase and glutathione reductase in the human lens related to age. Current Eye Research, 5, 381-385.
http://dx.doi.org/10.3109/02713688609025177

[32]   David, L.L. and Shearer, T.R. (1984) State of sulfhydryl in selenite cataract. Toxicology and Applied Pharmacology, 74, 109-115.
http://dx.doi.org/10.1016/0041-008X(84)90276-X

[33]   Calvin, H.I., Medvedovsky, C. and Worgul, B.V. (1986) Near-total glutathione depletion and age-specific cataracts induced by buthionine sulfoximine in mice. Science, 233, 553-555.
http://dx.doi.org/10.1126/science.3726547

[34]   Padgaonkar, V., Giblin, F.J. and Reddy, V.N. (1989) Disulfide cross-linking of urea-insoluble proteins in rab- bit lenses treated with hyperbaric oxygen. Experimental Eye Research, 49, 887-899.
http://dx.doi.org/10.1016/S0014-4835(89)80047-8

[35]   Dickerson, J.E. Jr., Dotzel, E. and Clark, A.F. (1997) Steroid-induced cataract: New perspective from in vitro and lens culture studies. Experimental Eye Research, 65, 507-516.
http://dx.doi.org/10.1006/exer.1997.0359

[36]   Nishigori, H., Kosano, H. and Umeda, I.O. (2004) Inhibition of glucocorticoid-induced cataracts in chick embryos by RU486: A model for studies on the role of glucocorticoids in development. Life Sciences, 75, 3027-3033.
http://dx.doi.org/10.1016/j.lfs.2004.04.051

[37]   Creighton, M.O., Sanwal, M., Stewart-DeHaan, P.J. and Trevithick, J.R. (1983) Modeling cortical cataractogenesis. V. Steroid cataracts induced by solumedrol partially prevented by vitamin E in vitro. Experimental Eye Research, 37, 65-76.
http://dx.doi.org/10.1016/0014-4835(83)90150-1

[38]   Hirsch, R.P. and Schwartz, B. (1983) Increased mortality among elderly patients undergoing cataract extraction. JAMA Ophthalmology, 101, 1034-1037.
http://dx.doi.org/10.1001/archopht.1983.01040020036004

[39]   Babizhayev, M.A., Burke, L., Micans, P. and Richer, S.P. (2009) N-Acetylcarnosine sustained drug delivery eye drops to control the signs of ageless vision: Glare sensitivity, cataract amelioration and quality of vision currently available treatment for the challenging 50,000-patient population. Clinical Interventions in Aging, 4, 31-50.

[40]   Zhang, S., Chai, F., Yan, H, Guo, Y. and Harding, J.J. (2008) Effects of N-acetylcysteine and glutathione ethyl ester drops on streptozotocin-induced diabetic cataract in rats. Molecular Vision, 14, 862-870.

[41]   Cotgreave, I.A. (1997) N-acetylcysteine: Pharmacological considerations and experimental and clinical applications. Advances in Pharmacology, 38, 205-227.
http://dx.doi.org/10.1016/S1054-3589(08)60985-0

[42]   Atlas, D., Melamed, E. and Offen, D. (1999) Brain targeted low molecular weight hydrophobic antioxidant compounds. US Patent No. 5874468.

[43]   Ates, B., Abraham, L. and Ercal, N. (2008) Antioxidant and free radical scavenging properties of N-acetylcysteine amide (NACA) and comparison with N-acetylcysteine (NAC). Free Radical Research, 42, 372-377.
http://dx.doi.org/10.1080/10715760801998638

[44]   Tobwala, S., Zhang, X., Zheng, Y., Wang, H.J., Banks, W.A. and Ercal, N. (2013) Disruption of the integrity and function of brain microvascular endothelial cells in culture by exposure to diesel engine exhaust particles. Toxicology Letters, 220, 1-7.
http://dx.doi.org/10.1016/j.toxlet.2013.03.023

[45]   Banerjee, A., Trueblood, M.B., Zhang, X., Manda, K.R., Lobo, P., Whitefield, P.D., Hagen, D.E. and Ercal, N. (2009) N-acetylcysteineamide (NACA) prevents inflammation and oxidative stress in animals exposed to diesel engine exhaust. Toxicology Letters, 187, 187-193.
http://dx.doi.org/10.1016/j.toxlet.2009.02.022

[46]   Carey, J.W., Pinarci, E.Y., Penugonda, S., Karacal, H. and Ercal, N. (2011) In vivo inhibition of l-buthionine- (S,R)-sulfoximine-induced cataracts by a novel antioxidant, N-acetylcysteine amide. Free Radical Biology and Medicine, 50, 722-729.
http://dx.doi.org/10.1016/j.freeradbiomed.2010.12.017

[47]   Grinberg, L., Fibach, E., Amer, J. and Atlas, D. (2005) N-acetylcysteine amide, a novel cell-permeating thiol, restores cellular glutathione and protects human red blood cells from oxidative stress. Free Radical Biology and Medicine, 38, 136-145.
http://dx.doi.org/10.1016/j.freeradbiomed.2004.09.025

[48]   Offen, D., Gilgun-Sherki, Y., Barhum, Y., Benhar, M., Grinberg, L., Reich, R., Melamed, E. and Atlas, D. (2004) A low molecular weight copper chelator crosses the blood-brain barrier and attenuates experimental autoimmune encephalomyelitis. Journal of Neurochemistry, 89, 1241-1251.
http://dx.doi.org/10.1111/j.1471-4159.2004.02428.x

[49]   Carey, J.W., Tobwala, S., Zhang, X., Banerjee, A., Ercal, N., Pinarci, E. and Karacal, H. (2012) N-acetyl L-cysteine amide protects retinal pigment epithelium against methamphetamine-induced oxidative stress. Journal of Biophysical Chemistry, 3, 101-110.
http://dx.doi.org/10.4236/jbpc.2012.32012

[50]   Tobwala, S., Fan, W., Stoeger, T. and Ercal, N. (2013) N-acetylcysteine amide, a thiol antioxidant, prevents bleomycin-induced toxicity in human alveolar basal epithelial cells (A549). Free Radical Research, 47, 740-749.
http://dx.doi.org/10.3109/10715762.2013.819974

[51]   Zhang, X., Tobwala, S. and Ercal, N. (2012) N-acetylcysteine amide protects against methamphetamine-induced tissue damage in CD-1 mice. Human & Experimental Toxicology, 31, 931-944.
http://dx.doi.org/10.1177/0960327112438287

[52]   Xie, G.L., Yan, H. and Lu, Z.F. (2011) Inhibition of glucocorticoid-induced alteration of vimentin by a glucocorticoid receptor antagonist RU486 in the organ-cultured rat lens. Molecular Vision, 17, 32-40.

[53]   Winters, R.A., Zukowski, J., Ercal, N., Matthews, R.H. and Spitz, D.R. (1995) Analysis of glutathione, glutathione disulfide, cysteine, homocysteine, and other biological thiols by high-performance liquid chromatography following derivatization by n-(1-pyrenyl) maleimide. Analytical Biochemistry, 227, 14-21.
http://dx.doi.org/10.1006/abio.1995.1246

[54]   Ates, B., Ercal, B.C., Manda, K., Abraham, L. and Ercal, N. (2009) Determination of glutathione disulfide levels in biological samples using thiol-disulfide exchanging agent, dithiothreitol. Biomedical Chromatography, 23, 119-123.
http://dx.doi.org/10.1002/bmc.1083

[55]   Draper, H.H., Squires, E.J., Mahmoodi, H., Wu, J., Agarwal, S. and Hadley, M. (1993) A comparative evaluation of thiobarbituric acid methods for the determination of malondialdehyde in biological materials. Free Radical Biology and Medicine, 15, 353-363.
http://dx.doi.org/10.1016/0891-5849(93)90035-S

[56]   Bhuyan, K.C. and Bhuyan, D.K. (1984) Molecular mechanism of cataractogenesis: III. Toxic metabolites of oxygen as initiators of lipid peroxidation and cataract. Current Eye Research, 3, 67-81.
http://dx.doi.org/10.3109/02713688408997188

[57]   Meister, A. (1991) Glutathione deficiency produced by inhibition of its synthesis, and its reversal; Applications in research and therapy. Pharmacology & Therapeutics, 51, 155-194.
http://dx.doi.org/10.1016/0163-7258(91)90076-X

[58]   Mitton, K.P., Dean, P.A.W., Dzialoszynski, T., Xiong, H., Sanford, S.E. and Trevithick, J.R. (1993) Modelling cortical cataractogenesis. 13. Early effects on lens ATP/ADP and glutathione in the strepto-zotocin rat model of the diabetic cataract. Experimental Eye Research, 56, 187-198.
http://dx.doi.org/10.1006/exer.1993.1026

[59]   Truscott, R.J. (2005) Age-related nuclear cataract-oxidation is the key. Experimental Eye Research, 80, 709-725.
http://dx.doi.org/10.1016/j.exer.2004.12.007

[60]   Lou, M.F. (2003) Redox regulation in the lens. Progress in Retinal and Eye Research, 22, 657-682.
http://dx.doi.org/10.1016/S1350-9462(03)00050-8

[61]   Wu, G., Fang, Y.Z., Yang, S., Lupton, J.R. and Turner, N.D. (2004) Glutathione metabolism and its implications for health. The Journal of Nutrition, 134, 489-492.

[62]   Agarwal, R. and Shukla, G.S. (1999) Potential role of cerebral glutathione in the maintenance of blood-brain barrier integrity in rat. Neurochemical Research, 24, 1507-1514.
http://dx.doi.org/10.1023/A:1021191729865

[63]   Pescosolido, N., Miccheli, A., Manetti, C., Iannetti, G.D., Feher, J. and Cavallotti, C. (2001) Metabolic changes in rabbit lens induced by treatment with dexamethasone. Ophthalmic Research, 33, 68-74.
http://dx.doi.org/10.1159/000055646

[64]   Nishigori, H., Hayashi, R., Lee, J.W., Maruyama, K. and Iwatsuru, M. (1985) Preventive effect of ascorbic acid against glucocorticoid-induced cataract formation of developing chick embryos. Experimental Eye Research, 40, 445-451. http://dx.doi.org/10.1016/0014-4835(85)90157-5

[65]   Nishigori, H., Yasunaga, M., Mizumura, M., Lee, J.W. and Iwatsuru, M. (1989) Preventive effects of pyrroloquinoline quinone on formation of cataract and decline of lenticular and hepatic glutathione of developing chick embryo after glucocorticoid treatment. Life Sciences, 45, 593-598.
http://dx.doi.org/10.1016/0024-3205(89)90044-1

[66]   Setogawa, T., Kosano, H., Ogihara-Umeda, I., Kayanuma, T. and Nishigori, H. (1994) Preventive effect of SA3443, a novel cyclic disulfide, on glucocorticoid-induced cataract formation of developing chick embryo. Experimental Eye Research, 58, 689-695.
http://dx.doi.org/10.1006/exer.1994.1066

[67]   Rikans, L.E. and Hornbrook, K.R. (1997) Lipid peroxidation, antioxidant protection and aging. Biochimica et Biophysica Acta, 1362, 116-127.
http://dx.doi.org/10.1016/S0925-4439(97)00067-7

[68]   Bhuyan, K.C., Bhuyan, D.K. and Podos, S.M. (1986) Lipid peroxidation in cataract of the human. Life Sciences, 38, 1463-1471.
http://dx.doi.org/10.1016/0024-3205(86)90559-X

[69]   Micelli-Ferrari, T., Vendemiale, G., Grattagliano, I., Boscia, F., Arnese, L., Altomare, E. and Cardia, L. (1996) Role of lipid peroxidation in the pathogenesis of myopic and senile cataract. British Journal of Ophthalmology, 80, 840-843.
http://dx.doi.org/10.1136/bjo.80.9.840

[70]   Simonelli, F., Nesti, A., Pensa, M., Romano, L., Savastano, S., Rinaldi, E. and Auricchio, G. (1989) Lipid peroxidation and human cataractogenesis in diabetes and severe myopia. Experimental Eye Research, 49, 181-187.
http://dx.doi.org/10.1016/0014-4835(89)90088-2

 
 
Top