Inhibitory effects of S-nitrosoglutathione on cell proliferation and DNA synthesis: possible role of glyoxalase I inactivation.
We investigated the inhibitory effects of S-nitrosoglutathione (GSNO) on cell proliferation, DNA synthesis and several enzymatic activities using spontaneously immortalized human endothelial cells (ECV304). Proliferation of ECV304 was inhibited by GSNO in a dose-dependent manner (125-1000 microM). DNA synthesis was decreased 2 h after addition of GSNO to cells and was markedly repressed from 20 h after the addition. The activity of ribonucleotide reductase, a rate-limiting enzyme for DNA synthesis, was unchanged in GSNO-treated cells. GSNO inhibited less than 40% of mitochondrial respiration activity, and the membrane potential and cellular levels of ATP were not significantly decreased by GSNO. GSNO had no inhibitory effect on activities of glutathione peroxidase, glutathione S-transferase and glutathione reductase. However, glyoxalase I (Glo I) activity was decreased to 20% of the control level within 60 min, and was consistently repressed during exposure to GSNO for 20 h. A membrane-permeable Glo I inhibitor, S-bromobenzylglutathione diethylester, inhibited proliferation of ECV304 cells, while methylglyoxal (MG), a toxic metabolite generated during glycolysis and a substrate for Glo I, failed to inhibit the cell growth even at 100 microM. Glo I in several mammalian cell lines was inactivated by GSNO with a pI shift. Although we failed to detect accumulation of MG under conditions of Glo I inactivation, these results suggest that the inhibitory effects of GSNO on cell proliferation and DNA synthesis might be at least partly due to inactivation of Glo I.
Mitsumoto
A
A
School of Pharmaceutical Sciences, Kitasato University, 5-9-1 Shirokane, Tokyo, 108-8641, Minato-ku, Japan.
Kim
K R
KR
Oshima
G
G
Nakagawa
Y
Y
D000818:Animals; D002455:Cell Division / Q000187:drug effects* / Q000502:physiology; D002460:Cell Line; D004247:DNA / Q000096:biosynthesis*; D005978:Glutathione / Q000031:analogs & derivatives; D006801:Humans; D007791:Lactoylglutathione Lyase / Q000037:antagonists & inhibitors / Q000378:metabolism*; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D020030:Nitric Oxide Donors / Q000494:pharmacology; D011765:Pyruvaldehyde / Q000378:metabolism; D026422:S-Nitrosoglutathione / Q000494:pharmacology*
D020030:Nitric Oxide Donors; D026422:S-Nitrosoglutathione; D011765:Pyruvaldehyde; D004247:DNA; D007791:Lactoylglutathione Lyase; D005978:Glutathione