Magnesium-DNA interactions and the possible relation of magnesium to carcinogenesis. Irradiation and free radicals

Anastassopoulou, J; Theophanides, T

dc.contributor.author	Anastassopoulou, J	en
dc.contributor.author	Theophanides, T	en
dc.date.accessioned	2014-03-01T11:44:31Z
dc.date.available	2014-03-01T11:44:31Z
dc.date.issued	2002	en
dc.identifier.issn	1040-8428	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/36990
dc.subject	5′-Guanosine monophosphate	en
dc.subject	Cancer	en
dc.subject	DNA	en
dc.subject	FAB-MS	en
dc.subject	Free radicals	en
dc.subject	FT-IR	en
dc.subject	Irradiation	en
dc.subject	Magnesium	en
dc.subject	Raman	en
dc.subject	Superoxide anions	en
dc.subject.classification	Oncology	en
dc.subject.classification	Hematology	en
dc.subject.other	cisplatin	en
dc.subject.other	free radical	en
dc.subject.other	hydroxyl radical	en
dc.subject.other	lead	en
dc.subject.other	lithium	en
dc.subject.other	magnesium	en
dc.subject.other	manganese	en
dc.subject.other	metal	en
dc.subject.other	oxygen radical	en
dc.subject.other	cancer radiotherapy	en
dc.subject.other	carcinogenesis	en
dc.subject.other	cell cycle	en
dc.subject.other	chemotherapy	en
dc.subject.other	conformational transition	en
dc.subject.other	DNA binding	en
dc.subject.other	DNA structure	en
dc.subject.other	drug DNA interaction	en
dc.subject.other	human	en
dc.subject.other	hypomagnesemia	en
dc.subject.other	magnesium deficiency	en
dc.subject.other	metal binding	en
dc.subject.other	nonhuman	en
dc.subject.other	review	en
dc.subject.other	5'-Guanylic Acid	en
dc.subject.other	Animals	en
dc.subject.other	Cations, Divalent	en
dc.subject.other	DNA	en
dc.subject.other	DNA Damage	en
dc.subject.other	DNA Repair	en
dc.subject.other	Guanine	en
dc.subject.other	Humans	en
dc.subject.other	Hydrogen Bonding	en
dc.subject.other	Hydroxyl Radical	en
dc.subject.other	Immunologic Deficiency Syndromes	en
dc.subject.other	Magnesium	en
dc.subject.other	Magnesium Deficiency	en
dc.subject.other	Neoplasms	en
dc.subject.other	Nucleic Acid Conformation	en
dc.subject.other	Oxidative Stress	en
dc.subject.other	Radiation Injuries	en
dc.subject.other	Radiation Tolerance	en
dc.subject.other	Radiotherapy	en
dc.subject.other	Rats	en
dc.subject.other	Superoxides	en
dc.subject.other	Whole-Body Irradiation	en
dc.title	Magnesium-DNA interactions and the possible relation of magnesium to carcinogenesis. Irradiation and free radicals	en
heal.type	other	en
heal.identifier.primary	10.1016/S1040-8428(02)00006-9	en
heal.identifier.secondary	http://dx.doi.org/10.1016/S1040-8428(02)00006-9	en
heal.language	English	en
heal.publicationDate	2002	en
heal.abstract	Magnesium deficiency causes renal complications. The appearance of several diseases is related to its depletion in the human body. In radiotherapy, as well as in chemotherapy, especially in treatment of cancers with cis-platinum, hypomagnesaemia is observed. The site effects of chemotherapy that are due to hypomagnesaemia are decreased using Mg supplements. The role of magnesium in DNA stabilization is concentration dependent. At high concentrations there is an accumulation of Mg binding, which induces conformational changes leading to Z-DNA, while at low concentration there is deficiency and destabilization of DNA. The biological and clinical consequences of abnormal concentrations are DNA cleavage leading to diseases and cancer. Carcinogenesis and cell growth are also magnesium-ion concentration dependent. Several reports point out that the interaction of magnesium in the presence of other metal ions showed that there is synergism with Li and Mn, but there is magnesium antagonism in DNA binding with the essential metal ions in the order: Zn > Mg > Ca. In the case of toxic metals such as Cd, Ga and Ni there is also antagonism for DNA binding. It was found from radiolysis of deaerated aqueous solutions of the nucleoside 5'-guanosine monophosphate (5'-GMP) in the presence as well as in the absence of magnesium ions that, although the addition of hydroxyl radicals ((OH)-O-.) has been increased by 2-fold, the opening of the imidazole ring of the guanine base was prevented. This effect was due to the binding of Mg2+ ions to N7 site of the molecule by stabilizing the five-member ring imitating cis-platinum. It was also observed using Fourier Transform Infrared spectroscopy, Raman spectroscopy and Fast Atom Bombardment mass spectrometry that (OH)-O-. radicals subtract H atoms from the C1', C4' and C5' sites of the nucleotide. Irradiation of 5'-GMP in the presence of oxygen (2.5 x 10(-4) M) shows that magnesium is released from the complex. There is spectroscopic evidence that superoxide anions (O-2(-.)) react with magnesium ions leading to magnesium release from the complex. From radiolysis data it was suggested that magnesium ions can act as radiosensitizers in the absence of oxygen, while in the presence of oxygen they act as protectors and stabilizers of DNA. (C) 2002 Elsevier Science Ireland Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCIENCE INC	en
heal.journalName	Critical Reviews in Oncology/Hematology	en
dc.identifier.doi	10.1016/S1040-8428(02)00006-9	en
dc.identifier.isi	ISI:000175260200007	en
dc.identifier.volume	42	en
dc.identifier.issue	1	en
dc.identifier.spage	79	en
dc.identifier.epage	91	en