Thiol and disulfide metabolites of the radiation protector and potential chemopreventive agent wr-2721 are linked to both its anti-cytotoxic and anti-mutagenic mechanisms of action

David J. Grdina, Naoyuki Shigematsu, Phylis Dale, Gerald L. Newton, Joseph A. Aguilera, Robert C. Fahey

Research output: Contribution to journalArticle

101 Citations (Scopus)

Abstract

The ability of the potential chemopreventive agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) to protect against radiation-induced mutagenesis at the hprt locus and cell killing was studied using CHO-AA8 cells incubated for 30 min at 37°C in growth medium containing its active thiol 2-[(aminopropyl)amino]ethanethiol (WR-1065). In parallel experiments, the thiol and disulfide forms of the drug present in cells and incubation medium were determined in order to identify which, if either, of the components were associated with the observed protective effects. Treatment with 4 mM WR-1065 produced significant intracellular levels of the thiol (WRSH) and disulfide (WRSS) forms of the drug, but also caused dramatic elevation of cellular glutathione (GSH) and cysteine levels, accompanied by marked protection against 60Co γ-photon- and neutron-induced cell killing and mutagenesis. When drug-treated cells were transferred to drug-free medium and incubated for 4 h at 37°C, levels of WRSH and WRSS and protection against cell killing decreased markedly, whereas levels of GSH and cysteine and protection against mutagenesis showed little change. GSH and cysteine levels were not associated with protection against radiation-induced mutagenesis, as established by experiments performed with buthionine sulfoximine to block GSH synthesis. These data do not support the hypothesis that modulation of GSH or cysteine levels by WR-1065 is a major mechanism accounting for protection. Protection against mutagenesis was seen for cells incubated in medium with concentrations of added WR-1065 as low as 10 μM, where cellular levels of WRSH and WRSS became difficult to measure (≦ 5 μM) and no protection against cell killing was found. An unexpected observation was that cells incubated in 40 μM WR-1065 incorporated the drug much more rapidly than expected for uptake by passive diffusion and concentrated the drug to a marked degree; this indicates that a cell-mediated transport system is involved in the uptake of WR-1065 at low drug concentrations.

Original languageEnglish
Pages (from-to)767-774
Number of pages8
JournalCarcinogenesis
Volume16
Issue number4
DOIs
Publication statusPublished - 1995 Apr
Externally publishedYes

Fingerprint

Mutagenesis
Metabolites
Sulfhydryl Compounds
Disulfides
Radiation
Cells
Drugs
Cell
Cysteine
Pharmaceutical Preparations
Cytoprotection
Radiation protection
Amifostine
Buthionine Sulfoximine
Cysteamine
Radiation Protection
CHO Cells
Neutrons
Photons
Experiments

ASJC Scopus subject areas

  • Statistics, Probability and Uncertainty
  • Applied Mathematics
  • Physiology (medical)
  • Physiology
  • Behavioral Neuroscience
  • Cancer Research

Cite this

Thiol and disulfide metabolites of the radiation protector and potential chemopreventive agent wr-2721 are linked to both its anti-cytotoxic and anti-mutagenic mechanisms of action. / Grdina, David J.; Shigematsu, Naoyuki; Dale, Phylis; Newton, Gerald L.; Aguilera, Joseph A.; Fahey, Robert C.

In: Carcinogenesis, Vol. 16, No. 4, 04.1995, p. 767-774.

Research output: Contribution to journalArticle

@article{8ffe8f4c86654932a691380c1453e666,
title = "Thiol and disulfide metabolites of the radiation protector and potential chemopreventive agent wr-2721 are linked to both its anti-cytotoxic and anti-mutagenic mechanisms of action",
abstract = "The ability of the potential chemopreventive agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) to protect against radiation-induced mutagenesis at the hprt locus and cell killing was studied using CHO-AA8 cells incubated for 30 min at 37°C in growth medium containing its active thiol 2-[(aminopropyl)amino]ethanethiol (WR-1065). In parallel experiments, the thiol and disulfide forms of the drug present in cells and incubation medium were determined in order to identify which, if either, of the components were associated with the observed protective effects. Treatment with 4 mM WR-1065 produced significant intracellular levels of the thiol (WRSH) and disulfide (WRSS) forms of the drug, but also caused dramatic elevation of cellular glutathione (GSH) and cysteine levels, accompanied by marked protection against 60Co γ-photon- and neutron-induced cell killing and mutagenesis. When drug-treated cells were transferred to drug-free medium and incubated for 4 h at 37°C, levels of WRSH and WRSS and protection against cell killing decreased markedly, whereas levels of GSH and cysteine and protection against mutagenesis showed little change. GSH and cysteine levels were not associated with protection against radiation-induced mutagenesis, as established by experiments performed with buthionine sulfoximine to block GSH synthesis. These data do not support the hypothesis that modulation of GSH or cysteine levels by WR-1065 is a major mechanism accounting for protection. Protection against mutagenesis was seen for cells incubated in medium with concentrations of added WR-1065 as low as 10 μM, where cellular levels of WRSH and WRSS became difficult to measure (≦ 5 μM) and no protection against cell killing was found. An unexpected observation was that cells incubated in 40 μM WR-1065 incorporated the drug much more rapidly than expected for uptake by passive diffusion and concentrated the drug to a marked degree; this indicates that a cell-mediated transport system is involved in the uptake of WR-1065 at low drug concentrations.",
author = "Grdina, {David J.} and Naoyuki Shigematsu and Phylis Dale and Newton, {Gerald L.} and Aguilera, {Joseph A.} and Fahey, {Robert C.}",
year = "1995",
month = "4",
doi = "10.1093/carcin/16.4.767",
language = "English",
volume = "16",
pages = "767--774",
journal = "Carcinogenesis",
issn = "0143-3334",
publisher = "Oxford University Press",
number = "4",

}

TY - JOUR

T1 - Thiol and disulfide metabolites of the radiation protector and potential chemopreventive agent wr-2721 are linked to both its anti-cytotoxic and anti-mutagenic mechanisms of action

AU - Grdina, David J.

AU - Shigematsu, Naoyuki

AU - Dale, Phylis

AU - Newton, Gerald L.

AU - Aguilera, Joseph A.

AU - Fahey, Robert C.

PY - 1995/4

Y1 - 1995/4

N2 - The ability of the potential chemopreventive agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) to protect against radiation-induced mutagenesis at the hprt locus and cell killing was studied using CHO-AA8 cells incubated for 30 min at 37°C in growth medium containing its active thiol 2-[(aminopropyl)amino]ethanethiol (WR-1065). In parallel experiments, the thiol and disulfide forms of the drug present in cells and incubation medium were determined in order to identify which, if either, of the components were associated with the observed protective effects. Treatment with 4 mM WR-1065 produced significant intracellular levels of the thiol (WRSH) and disulfide (WRSS) forms of the drug, but also caused dramatic elevation of cellular glutathione (GSH) and cysteine levels, accompanied by marked protection against 60Co γ-photon- and neutron-induced cell killing and mutagenesis. When drug-treated cells were transferred to drug-free medium and incubated for 4 h at 37°C, levels of WRSH and WRSS and protection against cell killing decreased markedly, whereas levels of GSH and cysteine and protection against mutagenesis showed little change. GSH and cysteine levels were not associated with protection against radiation-induced mutagenesis, as established by experiments performed with buthionine sulfoximine to block GSH synthesis. These data do not support the hypothesis that modulation of GSH or cysteine levels by WR-1065 is a major mechanism accounting for protection. Protection against mutagenesis was seen for cells incubated in medium with concentrations of added WR-1065 as low as 10 μM, where cellular levels of WRSH and WRSS became difficult to measure (≦ 5 μM) and no protection against cell killing was found. An unexpected observation was that cells incubated in 40 μM WR-1065 incorporated the drug much more rapidly than expected for uptake by passive diffusion and concentrated the drug to a marked degree; this indicates that a cell-mediated transport system is involved in the uptake of WR-1065 at low drug concentrations.

AB - The ability of the potential chemopreventive agent S-2-(3-aminopropylamino)ethylphosphorothioic acid (WR-2721) to protect against radiation-induced mutagenesis at the hprt locus and cell killing was studied using CHO-AA8 cells incubated for 30 min at 37°C in growth medium containing its active thiol 2-[(aminopropyl)amino]ethanethiol (WR-1065). In parallel experiments, the thiol and disulfide forms of the drug present in cells and incubation medium were determined in order to identify which, if either, of the components were associated with the observed protective effects. Treatment with 4 mM WR-1065 produced significant intracellular levels of the thiol (WRSH) and disulfide (WRSS) forms of the drug, but also caused dramatic elevation of cellular glutathione (GSH) and cysteine levels, accompanied by marked protection against 60Co γ-photon- and neutron-induced cell killing and mutagenesis. When drug-treated cells were transferred to drug-free medium and incubated for 4 h at 37°C, levels of WRSH and WRSS and protection against cell killing decreased markedly, whereas levels of GSH and cysteine and protection against mutagenesis showed little change. GSH and cysteine levels were not associated with protection against radiation-induced mutagenesis, as established by experiments performed with buthionine sulfoximine to block GSH synthesis. These data do not support the hypothesis that modulation of GSH or cysteine levels by WR-1065 is a major mechanism accounting for protection. Protection against mutagenesis was seen for cells incubated in medium with concentrations of added WR-1065 as low as 10 μM, where cellular levels of WRSH and WRSS became difficult to measure (≦ 5 μM) and no protection against cell killing was found. An unexpected observation was that cells incubated in 40 μM WR-1065 incorporated the drug much more rapidly than expected for uptake by passive diffusion and concentrated the drug to a marked degree; this indicates that a cell-mediated transport system is involved in the uptake of WR-1065 at low drug concentrations.

UR - http://www.scopus.com/inward/record.url?scp=0028953642&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0028953642&partnerID=8YFLogxK

U2 - 10.1093/carcin/16.4.767

DO - 10.1093/carcin/16.4.767

M3 - Article

C2 - 7728953

AN - SCOPUS:0028953642

VL - 16

SP - 767

EP - 774

JO - Carcinogenesis

JF - Carcinogenesis

SN - 0143-3334

IS - 4

ER -