First Author | Piwien-Pilipuk G | Year | 2002 |
Journal | J Biol Chem | Volume | 277 |
Issue | 14 | Pages | 11896-903 |
PubMed ID | 11809749 | Mgi Jnum | J:75791 |
Mgi Id | MGI:2177855 | Doi | 10.1074/jbc.M109530200 |
Citation | Piwien-Pilipuk G, et al. (2002) Impairment of mineralocorticoid receptor (MR)-dependent biological response by oxidative stress and aging: correlation with post-translational modification of MR and decreased ADP-ribosylatable level of elongating factor 2 in kidney cells. J Biol Chem 277(14):11896-903 |
abstractText | Acute and chronic treatments of mice with the glutathione-depleting agent, L-buthionine-(SR)-sulfoximine (BSO), impaired the mineralocorticoid receptor (MR)-dependent biological response by inhibiting aldosterone binding. This steroid-binding inhibition was fully reversed when reducing agents were added to kidney cytosol obtained from mice treated for 5 h, but it was only partially reversed in cytosol obtained from mice treated for 10 days. Although the oligomeric structure of the MR-hsp90 heterocomplex was always unaffected, a decreased amount of MR protein was evidenced after the long term treatment. Such a deleterious effect was correlated with a post-translational modification of MR, as demonstrated by an increased level of receptor carbonylation. In addition, a failure at the elongation/termination step was also observed during the receptor translation process in a reticulocyte lysate system. Thus, a high polyribosomes/monomers ratio and both increased proteolysis and decreased ADP-ribosylatable concentration of elongation factor 2 (EF-2) were shown. Importantly, similar observations were also performed in vivo after depletion of glutathione. Notwithstanding the EF-2 functional disruption, not all renal proteins were equally affected as the MR. Interestingly, both EF-2 and MR expressed in old mice were similarly affected as in L-buthionine-(SR)-sulfoximine-treated young mice. We therefore propose that a dramatic depletion of glutathione in kidney cells mimics the cumulative effect of aging which, at the end, may lead to a renal mineralocorticoid dysfunction. |