TY - JOUR
T1 - Synthesis and Characterization of Estrogen 2,3-and 3,4-Quinones. Comparison of DNA Adducts Formed by the Quinones versus Horseradish Peroxidase-Activated Catechol Estrogens
AU - Dwivedy, I.
AU - Devanesan, P.
AU - Cremonesi, P.
AU - Rogan, Eleanor G
AU - Cavalieri, Ercole
PY - 1992/11/1
Y1 - 1992/11/1
N2 - Catechol estrogens (CE) are among the major metabolites of estrone (E1) and 17β-estradiol (E2). Oxidation of these metabolites to semiquinones and quinones could generate ultimate carcinogenic forms of E1 and E2. The 2,3-and 3,4-quinones of E1 and E2 were synthesized by MnO2 oxidation of the corresponding CE, following the method for synthesizing E1-3,4-quinone [Abul-Hajj (1984) J. Steroid Biochem. 21,621-622]. Characterization of these compounds was accomplished by UV, nuclear magnetic resonance, and mass spectrometry. The relative stability of these compounds was determined in DMSO/H2O (2:1) at room temperature, and the 3,4-quinones were more stable than the 2,3-quinones. The four quinones directly reacted with calf thymus DNA to form DNA adducts analyzed by the 32P-postlabeling method. The adducts were compared to those formed when the corresponding CE were activated by horseradish peroxidase (HRP) to bind to DNA. The E1-and E2-2,3-quinones formed much higher levels of DNA adducts than the corresponding 3,4-quinones. In addition, many of the adducts (70-90%) formed by the E1-and E2-2,3-quinones appeared to be the same as those formed by activation of 2-OHE1 or 2-OHE2 by HRP to bind to DNA. Little overlap was observed between the adducts formed by E1-and E2-3,4-quinones and HRP-activated 4-OHE1 and 4-OHE2. These results suggest that semiquinones and/or quinones are ultimate reactive intermediates in the peroxidatic activation of catechol estrogens.
AB - Catechol estrogens (CE) are among the major metabolites of estrone (E1) and 17β-estradiol (E2). Oxidation of these metabolites to semiquinones and quinones could generate ultimate carcinogenic forms of E1 and E2. The 2,3-and 3,4-quinones of E1 and E2 were synthesized by MnO2 oxidation of the corresponding CE, following the method for synthesizing E1-3,4-quinone [Abul-Hajj (1984) J. Steroid Biochem. 21,621-622]. Characterization of these compounds was accomplished by UV, nuclear magnetic resonance, and mass spectrometry. The relative stability of these compounds was determined in DMSO/H2O (2:1) at room temperature, and the 3,4-quinones were more stable than the 2,3-quinones. The four quinones directly reacted with calf thymus DNA to form DNA adducts analyzed by the 32P-postlabeling method. The adducts were compared to those formed when the corresponding CE were activated by horseradish peroxidase (HRP) to bind to DNA. The E1-and E2-2,3-quinones formed much higher levels of DNA adducts than the corresponding 3,4-quinones. In addition, many of the adducts (70-90%) formed by the E1-and E2-2,3-quinones appeared to be the same as those formed by activation of 2-OHE1 or 2-OHE2 by HRP to bind to DNA. Little overlap was observed between the adducts formed by E1-and E2-3,4-quinones and HRP-activated 4-OHE1 and 4-OHE2. These results suggest that semiquinones and/or quinones are ultimate reactive intermediates in the peroxidatic activation of catechol estrogens.
UR - http://www.scopus.com/inward/record.url?scp=0027097569&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0027097569&partnerID=8YFLogxK
U2 - 10.1021/tx00030a016
DO - 10.1021/tx00030a016
M3 - Article
C2 - 1336990
AN - SCOPUS:0027097569
VL - 5
SP - 828
EP - 833
JO - Chemical Research in Toxicology
JF - Chemical Research in Toxicology
SN - 0893-228X
IS - 6
ER -