TY - JOUR
T1 - In vivo detection of a novel endogenous etheno-DNA adduct derived from arachidonic acid and the effects of antioxidants on its formation
AU - Fu, Ying
AU - Nath, Raghu G.
AU - Dyba, Marcin
AU - Cruz, Idalia M.
AU - Pondicherry, Sharanya R.
AU - Fernandez, Aileen
AU - Schultz, Casey L.
AU - Yang, Peiying
AU - Pan, Jishen
AU - Desai, Dhimant
AU - Krzeminski, Jacek
AU - Amin, Shantu
AU - Christov, Plamen P.
AU - Hara, Yukihiko
AU - Chung, Fung Lung
N1 - Funding Information:
We thank the Proteomics & Metabolomics Shared Resource of Lombardi Comprehensive Cancer Center (supported partially by NIH/NCI Grant P30-CA051008 ) for providing resources for the DNA adducts analysis. We thank Sanchita Sarangi, Ankeet Naik, and Simrandeep S. Sidhu for their help in DNA isolation and discussions; we also thank the Tissue Culture and Animal Core Facilities of Lombardi Cancer for the help in the in vivo bioassay. Y.F. thanks the Prevent Cancer Foundation (USA) for his postdoctoral fellowship (Carlucci Family Research Award). This work was supported by the National Institutes of Health ( RO1-CA-134892 to F.-L. Chung).
PY - 2014/8
Y1 - 2014/8
N2 - Previous studies showed that 7-(1′,2′-dihydroxyheptyl)- substituted etheno DNA adducts are products of reactions with the epoxide of (E)-4-hydroxy-2-nonenal, an oxidation product of ω-6 polyunsaturated fatty acids (PUFAs). In this work, we report the detection of 7-(1′,2′- dihydroxyheptyl)-1,N6-ethenodeoxyadenosine (DHHedA) in rodent and human tissues by two independent methods: a 32P-postlabeling/HPLC method and an isotope dilution liquid chromatography-electrospray ionization-tandem mass spectrometry method, demonstrating for the first time that DHHedA is a background DNA lesion in vivo. We showed that DHHedA can be formed upon incubation of arachidonic acid with deoxyadenosine, supporting the notion that ω-6 PUFAs are the endogenous source of DHHedA formation. Because cyclic adducts are derived from the oxidation of PUFAs, we subsequently examined the effects of antioxidants, α-lipoic acid, Polyphenon E, and vitamin E, on the formation of DHHedA and γ-hydroxy-1,N 2-propanodeoxyguanosine (γ-OHPdG), a widely studied acrolein-derived adduct arising from oxidized PUFAs, in the livers of Long Evans Cinnamon (LEC) rats. LEC rats are afflicted with elevated lipid peroxidation and prone to the development of hepatocellular carcinomas. The results showed that although the survival of LEC rats was increased significantly by α-lipoic acid, none of the antioxidants inhibited the formation of DHHedA, and only Polyphenon E decreased the formation of γ-OHPdG. In contrast, vitamin E caused a significant increase in the formation of both γ-OHPdG and DHHedA in the livers of LEC rats.
AB - Previous studies showed that 7-(1′,2′-dihydroxyheptyl)- substituted etheno DNA adducts are products of reactions with the epoxide of (E)-4-hydroxy-2-nonenal, an oxidation product of ω-6 polyunsaturated fatty acids (PUFAs). In this work, we report the detection of 7-(1′,2′- dihydroxyheptyl)-1,N6-ethenodeoxyadenosine (DHHedA) in rodent and human tissues by two independent methods: a 32P-postlabeling/HPLC method and an isotope dilution liquid chromatography-electrospray ionization-tandem mass spectrometry method, demonstrating for the first time that DHHedA is a background DNA lesion in vivo. We showed that DHHedA can be formed upon incubation of arachidonic acid with deoxyadenosine, supporting the notion that ω-6 PUFAs are the endogenous source of DHHedA formation. Because cyclic adducts are derived from the oxidation of PUFAs, we subsequently examined the effects of antioxidants, α-lipoic acid, Polyphenon E, and vitamin E, on the formation of DHHedA and γ-hydroxy-1,N 2-propanodeoxyguanosine (γ-OHPdG), a widely studied acrolein-derived adduct arising from oxidized PUFAs, in the livers of Long Evans Cinnamon (LEC) rats. LEC rats are afflicted with elevated lipid peroxidation and prone to the development of hepatocellular carcinomas. The results showed that although the survival of LEC rats was increased significantly by α-lipoic acid, none of the antioxidants inhibited the formation of DHHedA, and only Polyphenon E decreased the formation of γ-OHPdG. In contrast, vitamin E caused a significant increase in the formation of both γ-OHPdG and DHHedA in the livers of LEC rats.
UR - http://www.scopus.com/inward/record.url?scp=84901587470&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84901587470&partnerID=8YFLogxK
U2 - 10.1016/j.freeradbiomed.2014.04.032
DO - 10.1016/j.freeradbiomed.2014.04.032
M3 - Article
C2 - 24816294
AN - SCOPUS:84901587470
SN - 0891-5849
VL - 73
SP - 12
EP - 20
JO - Free Radical Biology and Medicine
JF - Free Radical Biology and Medicine
ER -