Guanine-specific DNA oxidation photosensitized by the tetraphenylporphyrin P(V) complex
Guanine-specific DNA oxidation photosensitized by the tetraphenylporphyrin P(V) complex
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DOI：
10.1142/s108842460600065x
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发表时间：
2006-11
影响因子：
1.5
通讯作者：
Kazutaka Hirakawa;S. Kawanishi;H. Segawa;T. Hirano
中科院分区：
文献类型：
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作者：
Kazutaka Hirakawa;S. Kawanishi;H. Segawa;T. Hirano
卟啉已被研究作为光动力疗法中的光敏剂。 DNA是敏化剂最重要的靶标之一。在本研究中，我们研究了二羟基P(V)四苯基卟啉(P(V)TPP)（一种阳离子水溶性卟啉）引起的光敏DNA损伤。 P(V)TPP 光敏鸟嘌呤特异性损伤 DNA 片段。 P(V)TPP 对单链 DNA 而非双链 DNA 造成严重的光损伤。高效液相色谱测定证实了2'-脱氧鸟苷的氧化产物8-oxo-7,8-二氢-2'-脱氧鸟苷（8-oxo-G）的形成，并表明单链DNA中8-oxo-G的含量高于双链DNA。活性氧清除剂对 DNA 损伤的影响表明单线态氧 (1O2) 的参与。通过近红外发射测量证实了光敏 1O2 的形成。结果表明，1O2 的形成主要有助于 P(V) 的 DNA 光损伤机制...
Porphyrins have been studied as photosensitizers in photodynamic therapy. DNA is one of the most important targets of the sensitizer. In the present study, we have examined the photosensitized DNA damage caused by dihydroxoP(V) tetraphenylporphyrin (P(V)TPP), a cationic water-soluble porphyrin. P(V)TPP photosensitized guanine-specific damage to the DNA fragment. P(V)TPP induced severe photodamage to single-stranded rather than to double-stranded DNA. High performance liquid chromatography measurements confirmed the formation of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxo-G), an oxidized product of 2'-deoxyguanosine, and showed that the content of 8-oxo-G in single-stranded DNA is larger than that in double-stranded DNA. The effects of reactive oxygen scavengers on DNA damage suggested the involvement of singlet oxygen (1O2). Photosensitized 1O2 formation was confirmed by near-infrared emission measurements. The results showed that 1O2 formation mainly contributes to the mechanism of DNA photodamage by P(V)...