Maternal Dietary Zinc Influences DNA Strand Break and 8-Hydroxy-2'-Deoxyguanosine Levels in Infant Rhesus Monkey Liver

Abstract

Severe zinc deficiency in rodent models has been shown to influence the frequency of single-strand breaks in DNA isolated from liver. In the current study, we investigated whether DNA isolated from infant monkeys born to mothers fed zinc-restricted diets would be characterized by higher than normal levels of DNA damage. DNA was isolated from 30-day-old infants born to dams fed low zinc (2 or 4 micrograms Zn/g) or control zinc (50 micrograms Zn/g) diets. The amount of single-strand breaks in liver DNA was significantly higher in the low zinc group than in controls; consistent with the above, there was a trend for higher steady state levels of liver 8-hydroxy-2'-deoxyguanosine in the low zinc group. While evidence for DNA damage in the low zinc group was obtained, the activities of several antioxidant enzymes were similar between the low zinc and control groups. In summary, infants born to monkeys fed low zinc diets are characterized by evidence of DNA damage shortly after birth; this damage may be due to an increased rate of oxidative damage and/or a reduction in the rate of DNA repair.