The effect of 2-[(aminopropyl)amino] ethanethiol (WR-1065) on radiation induced DNA double strand damage and repair in V79 cells

Sigdestad, Curtis P.; Treacy, S. H.; Knapp, Leslie A.; Grdina, D J

doi:10.1038/bjc.1987.97

Cited by 44 publications

(19 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Figure 3. In contrast to the protective effect previously reported for WR1065 with respect to DSB formation in the DNA of cells irradiated by y-rays (Sigdestad et al, 1987;Murray et al, 1988), the presence of this aminothiol during irradiation with high-LET JANUS neutrons had no protective effect.…”

Section: Dna Damagecontrasting

confidence: 52%

“…Neutral elution Neutral elution was performed at pH 7.2, as described in detail elsewhere (Bradley & Kohn, 1979;Sigdestad et al, 1987). Briefly, 5 x 105 cells were impinged onto a 25 mm diameter (0.8pm pore size) polycarbonate filter (Nucleopore Corp., Pleasanton, CA, USA).…”

Section: Irradiationmentioning

confidence: 99%

“…It is well known that selected aminothiol compounds can protect against the induction of single-and double-strand breaks in the DNA of irradiated cells (LaSalle & Billen, 1964;Sawada & Okada, 1970;Billen, 1983;Grdina & Nagy, 1986;Sigdestad et al, 1987;Murray et al, 1988 Accordingly, the US Government retains a non-exclusive, royaltyfree licence to publish or reproduce the published form of this contribution, or allow others to do so, for US Government purposes.…”

mentioning

confidence: 99%

“…It is well known that selected aminothiol compounds can protect against the induction of single-and double-strand breaks in the DNA of irradiated cells (LaSalle & Billen, 1964;Sawada & Okada, 1970;Billen, 1983;Grdina & Nagy, 1986;Sigdestad et al, 1987;Murray et al, 1988 clastogenic effects of high-LET fission spectrum neutrons Schwartz et al, 1988) …”

mentioning

confidence: 99%

See 3 more Smart Citations

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

Grdina

Cp²,

Dale³

et al. 1989

Br J Cancer

Self Cite

View full text Add to dashboard Cite

Summary The effect(s) of the radioprotector 2-[(aminopropyl)amino] ethanethiol (WR1065) on fissionneutron-induced DNA damage and repair in V79 Chinese hamster cells was determined by using a neutral filter elution procedure (pH7.2). When required, WR1065, at a final working concentration of 4mM, was added to the culture medium, either 30min before and during irradiation with fission spectrum neutrons (beam energy of 0.85MeV) from the JANUS research reactor, or for selected intervals of time following exposure. The frequency of neutron-induced DNA strand breaks as measured by neutral elution as a function of dose equalled that observed for 60Coy-ray-induced damage (relative biological effectiveness of one). In contrast to the protective effect exhibited by WR1065 in reducing 60Co-induced DNA damage, WR1065 was ineffective in reducing or protecting against induction of DNA strand breaks by JANUS neutrons. The kinetics of DNA double-strand rejoining were measured following neutron irradiation. In the absence of WR1065, considerable DNA degradation by cellular enzymes was observed. This process was inhibited when WR1065 was present. These results indicate that, under the conditions used, the quality (i.e. nature), rather than quantity, of DNA lesions (measured by neutral elution) formed by neutrons was significantly different from that formed by y-rays.WR 1065 is the corresponding free thiol of the wellcharacterised radioprotector S-2-(3-aminopropylamino) ethyl phosphorothioic acid designated WR2721 (Purdie, 1979). The current clinical interest in these and similar compounds stems from early reports that these agents can preferentially protect normal as compared to neoplastic tissues against both acute and late-arising radiation-and/or chemotherapyinduced injuries (Yuhas, 1979;Phillips, 1980;Glover et al., 1984;Kligerman et al., 1984). Thiol compounds such as WR2721 and cysteamine have also been reported to be effective in protecting against oncogenesis in a number of experimental rodent systems (Marquardt et al., 1974;Apffel et al., 1975;Takeuchi & Murakami, 1978;Milas et al., 1984;Grdina et al., 1985b).WR1065 and cysteamine can both protect against radiation induced mutagenesis at the hypoxanthine-guanine phosphoribosyl transferase (HGPRT) locus in mammalian cells (Grdina et al., 1985a;Corn et al., 1987). WR1065 has also been found to be effective in protecting against the induction of HGPRT mutants by cisplatin , bleomycin and nitrogen mustard (Nagy & Grdina, 1986) and the transformation of 10T1/2 cells by ionizing radiation (Hill et al., 1986).Linked to the expression of each of these deleterious endpoints are, presumably, factors involving DNA damage and repair. It is well known that selected aminothiol compounds can protect against the induction of single-and double-strand breaks in the DNA of irradiated cells (LaSalle & Billen, 1964;Sawada & Okada, 1970;Billen, 1983;Grdina & Nagy, 1986;Sigdestad et al., 1987;Murray et al., 1988 Accordingly, the US Government retains a non-exclusive, royaltyfree licence to pu...

show abstract

Section: Dna Damagecontrasting

confidence: 52%

Section: Irradiationmentioning

confidence: 99%

mentioning

confidence: 99%

“…It is well known that selected aminothiol compounds can protect against the induction of single-and double-strand breaks in the DNA of irradiated cells (LaSalle & Billen, 1964;Sawada & Okada, 1970;Billen, 1983;Grdina & Nagy, 1986;Sigdestad et al, 1987;Murray et al, 1988 clastogenic effects of high-LET fission spectrum neutrons Schwartz et al, 1988) …”

mentioning

confidence: 99%

See 2 more Smart Citations

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

Grdina

Cp²,

Dale³

et al. 1989

Br J Cancer

Self Cite

View full text Add to dashboard Cite

show abstract

“…The drug has also been shown to reduce the rate of single strand break repair but not the repair of another class of damage, double strand breaks (Sigdestad (Sigdestad et al, 1987). No comparable protection was seen using the nucleoid assay.…”

Section: Discussionmentioning

confidence: 99%

Conformational changes in chromatin structure induced by the radioprotective aminothiol, WR 1065

Vaughan

Grdina²,

Meechan³

et al. 1989

Br J Cancer

Self Cite

View full text Add to dashboard Cite

al., 1980; Phillips, 1980). The active form of this drug in vivo is thought to be the corresponding free thiol, 2-[(aminopropyl) amino] ethanethiol, WR 1065. These compounds have also been shown to limit radiation-induced carcinogenesis in experimental animals and cellular transformation in vitro (Milas et al., 1984;Hill et al., 1986).In addition to reducing the lethal, carcinogenic and transforming effects of radiation, WR 1065 also protects against the induction of mutations by gamma-rays, as shown in Chinese hamster V79 cells monitored at the HPRT locus (Grdina et al., 1989a, b). Protection against both gammaand neutron-induced mutagenesis was seen even if the drug was administered up to 3 h after irradiation (Grdina et al., 1985). This last observation is difficult to explain if the WR 1065 is acting solely as a free radical scavenger. Such free radicals have lifetimes that are usually less than a second, and thus will have reacted by the time WR 1065 is added. To investigate this apparent anomaly we have studied the effect of WR 1065 on radiation-induced DNA damage using two different end-points. The technique of alkaline elution of DNA from filters is thought to measure single strand breaks and alkali labile sites within bulk samples of DNA (Kohn, 1979). Radiation-induced nucleoid expansion, as modified by us, responds to the same type of damage but the data are generated from the replicon level of chromatin organisation. Replicons are supercoiled loops of DNA, attached at their base to the nuclear matrix, and are the repeating units for DNA synthesis. DNA synthesis is initiated at the matrix attachment site and proceeds bidirectionally around the loop to the periphery. Individual replicons can be unwound and then rewound into the nucleoid by exposing them to increasing concentrations of ethidium bromide (Cook & Brazell, 1976a;Vogelstein et al., 1980;Milner et al., 1987). Radiation damage to the replicon structures stops the ethidium driven rewinding, leading to a relaxation in absolute loop size and therefore nucleoid diameter (Cook & Brazell, 1976b). We detect damage to replicon structures as an increase in light scatter from ethidium bromide stained nucleoids when passed through a flow cytometer. Methods DNA strand breaksChinese hamster AA8 cells were grown as monolayers in alpha-minimal essential medium supplemented with 7.5% bovine:2.5% newborn calf serum, in the presence of penicillin and streptomycin. The cells were incubated for 3 days before use in 1.85 kBq ml-' (0.05 tsCi ml-') tritiated thymidine.Before irradiation they were trypsinised, washed in complete media, adjusted to 2.5 x 106ml-' and then exposed on ice to graded doses of cobalt-60 gamma-rays at 1 Gy min-'. WR 1065 was freshly prepared as a IM solution and added to I ml of cells to give a 4 mM final concentration. These cells were then incubated for 30 min at 37°C before irradiation.Within I h of irradiation 200 Fl aliquots of the cell suspension were loaded on to 25 mm polycarbonate filters (0.8 gim pore size; Nucleopore), lysed, was...

show abstract

Induction of micronuclei by bleomycin in G₀ human lymphocytes: II. Potentiation by radioprotectors

1993

Environ and Mol Mutagen

View full text Add to dashboard Cite

Dimethylsulfoxide (DMSO) and WR-1065 are radioprotectors, in that they reduce the effectiveness with which ionizing radiation causes genetic damage. Unlike their protective effects with radiation, these agents potentiate the induction of micronuclei by bleomycin in the cytokinesis-block assay in G0 human lymphocytes. High concentrations of DMSO (1 M) are required to cause potentiation. In contrast, WR-1065 causes dose-dependent potentiation at relatively low concentrations (1.25 to 10 mM). Cytogenetic analysis supports the results from the micronucleus assay, showing higher levels of genetic damage induced by the combination of bleomycin with DMSO or WR-1065 than by bleomycin alone. Possible mechanisms of potentiation are proposed.

show abstract

The effect of 2-[(aminopropyl)amino] ethanethiol (WR-1065) on radiation induced DNA double strand damage and repair in V79 cells

Cited by 44 publications

References 13 publications

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

Conformational changes in chromatin structure induced by the radioprotective aminothiol, WR 1065

Induction of micronuclei by bleomycin in G₀ human lymphocytes: II. Potentiation by radioprotectors

Contact Info

Product

Resources

About

The effect of 2-[(aminopropyl)amino] ethanethiol (WR-1065) on radiation induced DNA double strand damage and repair in V79 cells

Cited by 44 publications

References 13 publications

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

The effect of 2-[(aminopropyl)amino] ethanethiol on fission-neutron-induced DNA damage and repair

Conformational changes in chromatin structure induced by the radioprotective aminothiol, WR 1065

Induction of micronuclei by bleomycin in G0 human lymphocytes: II. Potentiation by radioprotectors

Contact Info

Product

Resources

About

Induction of micronuclei by bleomycin in G₀ human lymphocytes: II. Potentiation by radioprotectors