Michele La Merrill, Ph.D.; Emma Kerry
University of California, Davis
NIEHS Grants R00ES019919, T32ES007059
An NIEHS grantee and colleagues report that female offspring of pregnant mice exposed to the pesticide dichlorodiphenyltrichloroethane (DDT) have increased risk for obesity, diabetes, high cholesterol, and related conditions later in life. The study is one of the first linking DDT exposure with higher risk of developing metabolic syndrome as an adult.
Even though DDT was banned in the United States more than 40 years ago, it persists in the environment and is still used to control malaria in other parts of the world. People exposed to elevated levels of DDT and its metabolite dichlorodiphenyldichloroethylene (DDE) are more likely to have diabetes and insulin resistance. To find out if DDT impairs metabolism and energy expenditure, the researchers exposed mice from gestational day 11.5 to postnatal day 5 to doses of DDT comparable to exposures of people living in malaria-infested regions and of pregnant mothers of U.S. adults who are now in their mid-50s.
The female offspring that experienced the DDT exposure showed reduced core body temperature, impaired cold tolerance, decreased energy expenditure, and a temporary early-life increase in body fat. In males, DDT exposure did not affect obesity or cholesterol levels and caused only a minor increase in glucose levels. The researchers gave the DDT-exposed offspring a high-fat diet for 12 weeks during adulthood, and found that the female mice developed glucose intolerance, excess insulin levels and abnormal amount of lipids circulating in the blood, and altered bile acid metabolism. The female mice fed the high-fat diet also showed further reductions in core temperature.
The researchers say that, based on their findings, perinatal DDT exposure is likely a risk factor for reduced energy expenditure in people, even decades after DDT use had stopped.
Citation: La Merrill M, Karey E, Moshier E, Lindtner C, La Frano MR, Newman JW, Buettner C. 2014. Perinatal Exposure of Mice to the Pesticide DDT Impairs Energy Expenditure and Metabolism in Adult Female Offspring. PLoS One 30;9(7):e103337.