Assessment of Genotoxic and Cytotoxic Hazards in Brain and Bone Marrow Cells of Newborn Rats Exposed to Extremely Low-Frequency Magnetic Field

The present study aimed to evaluate the association between whole body exposure to extremely low frequency magnetic field (ELF-MF) and genotoxic , cytotoxic hazards in brain and bone marrow cells of newborn rats. Newborn rats (10 days after delivery) were exposed continuously to 50 Hz, 0.5 mT for 30 days. The control group was treated as the exposed one with the sole difference that the rats were not exposed to magnetic field. Comet assay was used to quantify the level of DNA damage in isolated brain cells. Also bone marrow cells were flushed out to assess micronucleus induction and mitotic index. Spectrophotometric methods were used to measure the level of malondialdehyde (MDA) and the activity of glutathione (GSH) and superoxide dismutase (SOD). The results showed a significant increase in the mean tail moment indicating DNA damage in exposed group (P < 0.01, 0.001, 0.0001). Moreover ELF-MF exposure induced a significant (P < 0.01, 0.001) four folds increase in the induction of micronucleus and about three folds increase in mitotic index (P < 0.0001). Additionally newborn rats exposed to ELF-MF showed significant higher levels of MDA and SOD (P < 0.05). Meanwhile ELF-MF failed to alter the activity of GSH. In conclusion, the present study suggests an association between DNA damage and ELF-MF exposure in newborn rats.

[1]  Robert L. Elston,et al.  Chemical mutagens. Principles and methods for their detection. Volume 2 , 1971 .

[2]  Aaas News,et al.  Book Reviews , 1893, Buffalo Medical and Surgical Journal.

[3]  L. Knudsen,et al.  The comet assay as a rapid test in biomonitoring occupational exposure to DNA-damaging agents and effect of confounding factors. , 2000, Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology.

[4]  J. Crapo,et al.  Biology of disease: free radicals and tissue injury. , 1982, Laboratory investigation; a journal of technical methods and pathology.

[5]  W. Schmid.  The Micronucleus Test for Cytogenetic Analysis , 1976 .

[6]  B. Lucchesi.  Free radicals and tissue injury , 1998 .

[7]  K. Yagi,et al.  The occurrence of superoxide anion in the reaction of reduced phenazine methosulfate and molecular oxygen. , 1972, Biochemical and biophysical research communications.

[8]  E. Beutler,et al.  Improved method for the determination of blood glutathione. , 1963, The Journal of laboratory and clinical medicine.

[9]  A. Favier,et al.  Influence of static magnetic field on cadmium toxicity: study of oxidative stress and DNA damage in rat tissues. , 2006, Journal of trace elements in medicine and biology : organ of the Society for Minerals and Trace Elements.

[10]  F. Serres.  CHEMICAL MUTAGENS: PRINCIPLES AND METHODS FOR THEIR DETECTION , 1972 .

[11]  S. Monarca,et al.  Genotoxic hazard evaluation in welders occupationally exposed to extremely low-frequency magnetic fields (ELF-MF). , 2011, International journal of hygiene and environmental health.

[12]  Narendra Singh,et al.  Melatonin and N‐tert‐butyl‐α‐phenylnitrone block 60‐Hz magnetic field‐induced DNA single and double strand breaks in rat brain cells , 1997, Journal of pineal research.

[13]  K. Mclauchlan,et al.  Free radical mechanism for the effects of environmental electromagnetic fields on biological systems. , 1996, International journal of radiation biology.

[14]  H. Berg,et al.  Problems of weak electromagnetic field effects in cell biology. , 1999, Bioelectrochemistry and bioenergetics.

[15]  L. Paulsson,et al.  DNA damage, cell kinetics and ODC activities studied in CBA mice exposed to electromagnetic fields generated by transmission lines. , 1999, In vivo.

[16]  R. Tice,et al.  A simple technique for quantitation of low levels of DNA damage in individual cells. , 1988, Experimental cell research.

[17]  N. Wertheimer,et al.  Electrical wiring configurations and childhood cancer. , 1979, American journal of epidemiology.

[18]  N. Hsia,et al.  The toxicities of native and modified hemoglobins. , 1997, Free radical biology & medicine.

[19]  D D Ager,et al.  Effect of 60-Hz magnetic fields on ultraviolet light-induced mutation and mitotic recombination in Saccharomyces cerevisiae. , 1992, Mutation research.

[20]  Svedenstål Bm,et al.  DNA damage induced in brain cells of CBA mice exposed to magnetic fields. , 1999 .

[21]  W. Awara,et al.  Assessment of vinyl chloride-induced DNA damage in lymphocytes of plastic industry workers using a single-cell gel electrophoresis technique. , 1998, Toxicology.

[22]  Narendra Singh,et al.  Magnetic-field-induced DNA strand breaks in brain cells of the rat. , 2004, Environmental health perspectives.

[23]  R. Tice,et al.  Single cell gel/comet assay: Guidelines for in vitro and in vivo genetic toxicology testing , 2000, Environmental and molecular mutagenesis.

[24]  V. Caracciolo,et al.  Fifty hertz extremely low‐frequency magnetic field exposure elicits redox and trophic response in rat‐cortical neurons , 2009, Journal of cellular physiology.

[25]  J. Miyakoshi,et al.  Increased chromatid-type chromosomal aberrations in mouse m5S cells exposed to power-line frequency magnetic fields. , 2000, International journal of radiation biology.

[26]  Polycarpos Pissis,et al.  Role of oxidative stress and DNA damage in human carcinogenesis. , 2011, Mutation research.

[27]  W. Marsden.  I and J , 2012 .

[28]  C. Tanzarella,et al.  Clastogenicity and aneuploidy in newborn and adult mice exposed to 50 Hz magnetic fields , 2006, International journal of radiation biology.

[29]  J. Cristol,et al.  [Nitric oxide and lipid peroxidation]. , 1995, Comptes rendus des seances de la Societe de biologie et de ses filiales.

[30]  R. Pasquini,et al.  Micronucleus induction in cells co-exposed in vitro to 50 Hz magnetic field and benzene, 1,4-benzenediol (hydroquinone) or 1,2,4-benzenetriol. , 2003, Toxicology in vitro : an international journal published in association with BIBRA.

[31]  R. Hesketh,et al.  Biological responses to electromagnetic fields 1 , 1998, FASEB journal : official publication of the Federation of American Societies for Experimental Biology.

[32]  R. Cooke.  Biology of Disease , 1948, The Yale Journal of Biology and Medicine.

[33]  G. Obe,et al.  Cytological effects of 50 Hz electromagnetic fields on human lymphocytes in vitro. , 1995, Mutation research.

[34]  E. Wood,et al.  Biology of Disease , 2006 .

[35]  D. K. Agarwal,et al.  An improved chemical substitute for fetal calf serum for the micronucleus test. , 1993, Biotechnic & histochemistry : official publication of the Biological Stain Commission.

[36]  M. Uchiyama,et al.  Determination of malonaldehyde precursor in tissues by thiobarbituric acid test. , 1978, Analytical biochemistry.

[37]  H. Lai,et al.  Acute exposure to a 60 Hz magnetic field increases DNA strand breaks in rat brain cells. , 1997, Bioelectromagnetics.