A novel approach to enhancing cellular glutathione levels. Export

@article{citeulike:3401858, abstract = {GSH and GSH-associated metabolism provide the major line of defense for the protection of cells from oxidative and other forms of toxic stress. Of the three amino acids that comprise GSH, cysteine is limiting for GSH synthesis. As extracellularly cysteine is readily oxidized to form cystine, cystine transport mechanisms are essential to provide cells with cysteine. Cystine uptake is mediated by system x(c)(-), a Na(+)-independent cystine/glutamate antiporter. Inhibition of system x(c)(-) by millimolar concentrations of glutamate, a pathway termed oxidative glutamate toxicity, results in GSH depletion and nerve cell death. Recently, we described a series of compounds derived from the conjugation of epicatechin (EC) with cysteine and cysteine derivatives that protected nerve cells in culture from oxidative glutamate toxicity by maintaining GSH levels. In this study, we characterize an additional EC conjugate, cysteamine-EC, that is 5- to 10-fold more potent than the earlier conjugates. In addition, we show that these EC conjugates maintain GSH levels by enhancing the uptake of cystine into cells through induction of a disulfide exchange reaction, thereby uncoupling the uptake from system x(c)(-). Thus, these novel EC conjugates have the potential to enhance GSH synthesis under a wide variety of forms of toxic stress.}, author = {Maher, Pamela and Lewerenz, Jan and Lozano, Carles and Torres, Josep Llu\'{\i}s L.}, citeulike-article-id = {3401858}, citeulike-linkout-0 = {http://dx.doi.org/10.1111/j.1471-4159.2008.05620.x}, citeulike-linkout-1 = {http://www.ingentaconnect.com/content/bsc/jnc/2008/00000107/00000003/art00010}, citeulike-linkout-2 = {http://view.ncbi.nlm.nih.gov/pubmed/18702664}, citeulike-linkout-3 = {http://www.hubmed.org/display.cgi?uids=18702664}, doi = {10.1111/j.1471-4159.2008.05620.x}, issn = {1471-4159}, journal = {Journal of neurochemistry}, keywords = {glutathione, xc\_tranporter}, month = {November}, number = {3}, pages = {690--700}, posted-at = {2009-04-12 03:08:53}, priority = {3}, publisher = {Blackwell Publishing}, title = {A novel approach to enhancing cellular glutathione levels.}, url = {http://dx.doi.org/10.1111/j.1471-4159.2008.05620.x}, volume = {107}, year = {2008} }

TY - JOUR ID - citeulike:3401858 L3 - citeulike-article-id:3401858 N2 - GSH and GSH-associated metabolism provide the major line of defense for the protection of cells from oxidative and other forms of toxic stress. Of the three amino acids that comprise GSH, cysteine is limiting for GSH synthesis. As extracellularly cysteine is readily oxidized to form cystine, cystine transport mechanisms are essential to provide cells with cysteine. Cystine uptake is mediated by system x(c)(-), a Na(+)-independent cystine/glutamate antiporter. Inhibition of system x(c)(-) by millimolar concentrations of glutamate, a pathway termed oxidative glutamate toxicity, results in GSH depletion and nerve cell death. Recently, we described a series of compounds derived from the conjugation of epicatechin (EC) with cysteine and cysteine derivatives that protected nerve cells in culture from oxidative glutamate toxicity by maintaining GSH levels. In this study, we characterize an additional EC conjugate, cysteamine-EC, that is 5- to 10-fold more potent than the earlier conjugates. In addition, we show that these EC conjugates maintain GSH levels by enhancing the uptake of cystine into cells through induction of a disulfide exchange reaction, thereby uncoupling the uptake from system x(c)(-). Thus, these novel EC conjugates have the potential to enhance GSH synthesis under a wide variety of forms of toxic stress. IS - 3 JF - Journal of neurochemistry SN - 1471-4159 EP - 700 TI - A novel approach to enhancing cellular glutathione levels. PB - Blackwell Publishing VL - 107 SP - 690 KW - glutathione KW - xc_tranporter AU - Maher, Pamela AU - Lewerenz, Jan AU - Lozano, Carles AU - Torres, Josep Lluís PY - 2008/11// UR - http://dx.doi.org/10.1111/j.1471-4159.2008.05620.x ER -