Epigenetics is the study of how different biological and environmental signals affect gene expression. Rather than change DNA itself, epigenetic signals can, for example, encourage changes in the number of methyl chemical groups attached to a gene, turning it on or off.
What we eat is an important source of epigenetic signals, and scientists are investigating how eating habits modify gene expression in adults and their offspring. Understanding that relationship could help researchers identify nutritional elements that might help prevent or treat diseases such as obesity, diabetes, coronary artery disease, cancer and Alzheimer’s.
Epidemiological studies show how certain exposures have shaped the health of specific populations over time, particularly between mother and child. One famous example is the Dutch Hunger Winter. In 1944, a famine struck the western Netherlands, forcing inhabitants—including pregnant mothers—to live on between 400 and 800 calories a day. When scientists later studied the babies conceived, carried, or delivered during this period, they found elevated rates of obesity, altered lipid profiles and cardiovascular disease in adulthood.
Research has also shown that the environments we grow up in can also cause improper regulation of inflammation during adulthood. One cohort comprised over 3,000 pregnant women recruited in the Philippines in 1983. These women came from all different aspects of life: They differed in access to clean water or a roof over their heads, whether they lived in an urban or a rural area, and whether they came into frequent contact with animals. The data looked at over 500 of those women in order to figure out if their child’s environment growing up led to epigenetic modifications to their DNA and later to a change in inflammatory proteins in their blood in adulthood.
Once their children were born, the investigators kept track of them and of the environments they were exposed to throughout their lives. Once they turned 21, the investigators took a blood sample that they used to measure the DNA methylation throughout their genome, as well as inflammation-related proteins that have been previously associated with cardiovascular diseases and other aging-related diseases.
The authors determined that the childhood environment of these youths affected the level of inflammation-related proteins in their blood during adulthood, likely as a result of methylation of some of their inflammation-related genes. The dysregulation of these proteins can affect health and risk of disease.
Comments