Genotoxicity and Fetal Abnormality in Streptozotocin-Induced Diabetic Rats Exposed to Cigarette Smoke Prior to and During Pregnancy

Abstract

Background: Maternal hyperglycemia during early pregnancy is associated with increased risk of abnormalities in the offspring. Malformation rates among the offspring of diabetic mothers are 2–5-fold higher than that of the normal population, and congenital malformations are the major cause of mortality and morbidity in the offspring of diabetic mothers. Metabolic changes, such as hyperglycemia and the metabolites obtained from cigarettes both increase the production of reactive oxygen species (ROS) in the embryo or fetus, causing DNA damage.

Objective: To evaluate the maternal and fetal genotoxicity, and to assess the incidence of fetal anomaly in diabetic female rats exposed to cigarette smoke at different stages of pregnancy in rats.

Material and Method: Diabetes was induced by streptozotocin administration and cigarette smoke exposure was produced by a mechanical smoking device that generated mainstream smoke that was delivered into a chamber. Female Wistar rats were randomly assigned to: non-diabetic (ND) and diabetic (D) groups exposed to filtered air; a diabetic group exposed to cigarette smoke prior to and during pregnancy (DS) and a diabetic group only exposed to cigarette smoke prior to pregnancy (DSPP). On pregnancy day 21, blood samples were obtained for DNA damage analysis and fetuses were collected for congenital anomaly assessment. Statistical significance was set at p<0.05 for all analysis.

Results and Conclusion: Exposure of diabetic rats to tobacco smoke prior to pregnancy increased fetal DNA damage, but failed to induce teratogenicity. Thus, these results reinforce the importance for women to avoid exposure to cigarette smoke long before they become pregnant.

Key words

diabetes - cigarette smoke - pregnancy - genotoxicity - fetal anomaly - rat

References

• 1 American Diabetes Association . Diagnosis and classification of diabetes mellitus.  Diabetes Care. 2009;  32 S62-S67
• 2 Aliverti V, Bonanomi L, Giavini E. et al . The extent of fetal ossification as an index of delayed development in teratogenic studies on the rat.  Teratology. 1979;  20 237-242
• 3 Assis KR, Ladeira MS, Bueno RC. et al . Genotoxicity of cigarette smoking in maternal and newborn lymphocytes.  Mutat Res. 2009;  679 72-78
• 4 Autrup H, Vestergaard AB. Transplacental transfer of environmental genotoxins – polycyclic aromatic hydrocarbon-albumins in nonsmoking women.  Environ Health Perspect. 1996;  104 625-627
• 5 Damasceno DC, Volpato GT, Calderon IMP. et al . Oxidative stress and diabetes in pregnancy rats.  Anim Reprod Sci. 2002;  72 235-244
• 6 Dempsey DA, Benowitz NL. Risks and benefits of nicotine to aid smoking cessation in pregnancy.  Drug Saf. 2001;  24 277-322
• 7 de Souza Mda S, Lima PHO, Sinzato YK. et al . Effects of cigarette smoke exposure on pregnancy outcome and offspring of diabetic rats.  Reprod Biomed Online. 2009;  18 582-587
• 8 de Souza Mda S, Sinzato YK, Lima PHO. et al . Oxidative stress status and lipid profiles of diabetic pregnant rats exposed to cigarette smoke.  Reprod Biomed Online. 2010;  20 547-552
• 9 Eriksson UJ. Congenital anomalies in diabetic pregnancy.  Semin Fetal Neontal Med. 2009;  14 85-93
• 10 Eriksson UF, Cederberg J, Wentzel P. Congenital malformations in offspring of diabetic mothers – Animal and human studies.  Rev Endocr Metab Disord. 2003;  4 79-93
• 11 Ermis B, Ors R, Yildirim A. et al . Influence of smoking on maternal and neonatal serum malondialdehyde, superoxide dismutase and glutathione peroxidase levels.  Ann Clin Lab Sci. 2004;  34 405-409
• 12 Florek E, Tadrowska M, Szyfter K. Tobacco smoke-induced DNA strand breaks in rat estimated by comet assay.  Toxicol Lett. 1998;  95 186
• 13 Gladden BC, Zadorozhnaja TD, Chislovska N. Polycyclic aromatic hydrocarbons in placenta.  Hum Exp Toxicol. 2000;  19 597-603
• 14 Lima PH, Damasceno DC, Sinzato YK. et al . Levels of DNA damage in blood leukocyte samples from non-diabetic and diabetic female rats and their fetuses exposed to air or cigarette smoke.  Mutat Res. 2008;  653 44-49
• 15 Lodovici M, Akpan V, Evangelisti C. et al . Sidestream tobacco smoke as main predictor of exposure to polycyclic aromatic hydrocarbons.  J Appl Toxicol. 2004;  24 277-281
• 16 Miller MS. Transplacental lung carcinogenesis: molecular mechanisms and pathogenesis.  Toxicol Appl Pharmacol. 2004;  198 95-110
• 17 Ornoy A. Embryonic oxidative stress as a mechanism of teratogenesis with special emphasis on diabetic embryopathy.  Reprod Toxicol. 2007;  24 31-41
• 18 Staples RE, Schnell VL. Refinements in rapid clearing technic in the KOH-alizarin red S method for fetal bone.  Stain Technol. 1964;  39 61-63
• 19 Volpato GT, Damasceno DC, Rudge MVC. et al . Effect of Bauhinia forficata aqueous extract on the maternal-fetal outcome and oxidative stress biomarkers of streptozotocin-induced diabetic rats.  J Etnopharmacol. 2008;  116 131-137
• 20 Volpato GT, Damasceno DC, Kempinas WG. et al . Effect of exercise on the reproductive outcome and fetal development of diabetic rats.  Reprod Biomed Online. 2009;  19 852-858
• 21 Wilson JC. Methods for administering agents and detecting malformations in experimental animal.. In: Wilson JC, Warkany J (Eds). Teratology: principles and techniques. Chicago: Univ. of Chicago Press; 1965: 262-327
• 22 World Health Organization . The World Health Report 2002: Reducing risks, promoting healthy life.  World Health Organization, Geneva 2002; 
• 23 Zangen SW, Yafee P, Kohen R. et al . The role of reactive oxygen species in diabetes-induced anomalies in embryos of Cohen diabetic rats.  Int J Exp Diabetes Res. 2002;  3 247-255
• 24 Zhao Z, Reece EA. Nicotine-induced embryonic malformations mediated by apoptosis from increasing intracellular calcium and oxidative stress.  Birth Defects Res B Dev Reprod Toxicol. 2005;  74 383-391

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