Prairie Vole Study: Fathers Matter More Than You Think
Scientific studies are leaving no doubt that children - and especially boys - who grow up in environments with high levels of social and emotional support tend to experience longer, healthier lives. Conversely, early neglect or trauma can have adverse consequences.
The biological mechanisms that might allow this to happen have been a mystery, but recently, clues to this important puzzle have begun to emerge from animal research conducted at the University of Virginia in the laboratory of Psychology Professor Jess Connelly.
Using a rodent model, a team of scientists led by Joshua Danoff discovered that the amount of care offered to sons by fathers has the capacity to literally sculpt the developing nervous system and slow aging, while changing gene expression in the brain and behavioral patterns later life.
These startling conclusions arise from experiments conducted in a small mammal known as the prairie vole. Prairie voles share with humans a lifestyle, known in biology as “social monogamy,” in which both mothers and fathers care for and protect the young. However, as in humans, vole fathers - more than mothers – vary widely in the amount of care they offer their young. This unique social structure allowed the team in Connelly’s lab to examine how a highly enriched early life experience — in particular, one featuring the active role of fathers — impacts the development of offspring.
“I’m really interested in how experience affects development, and one of the reasons that I went to do my training with Jess was because of the prairie vole’s co-parenting model of the pups, their development is a lot more varied than you might get with just one parent,” said Danoff, who earned his Ph.D. from UVA this spring and is now a postdoctoral researcher at Rutgers University.
Young males that received high levels of care from fathers in early life subsequently were more socially responsive to babies. Remarkably, the brains of these highly nurtured young males were structurally different in brain areas, such as the nucleus accumbens, that regulate the capacity for reward. Males reared by high-nurture fathers also had changes in gene expression, specifically in genes that have previously been implicated in human sociality.
Perhaps even more remarkable was the finding that both males and females that had received extra “fathering” had levels of DNA methylation that indicate slower “epigenetic aging”: a measurement that reflects the “actual” age of our cells, tissues and organ systems.
“The way that the environment impacts your physiology can actually make you age quicker or slower than your actual chronological age,” Connelly said. “And we found that the animals that received high-care parenting actually were much younger epigenetically than those that did not. That’s a really important point: having a nurturing environment and having high-care parents is going to lead to a lower epigenetic age, which then actually might set you up to live longer.”
Although many questions remain to be explored, the authors of this work are quick to remind us that the behaviors seen in their work probably reflect an enhancement of neural endocrine patterns leading to high amounts of social behaviors, even by standards typical for prairie voles. In other words, the highly nurtured males may be experiencing development at a level beyond that seen in prairie voles reared by lower-care parents, becoming metaphorically little voles with “superpowers.” Whether comparable processes exist in humans is obviously not known, but these findings open intriguing possibilities.
These studies were published on July 24 in the Proceedings of the National Academy of Sciences. This study depended on the efforts of a large team of scientists, including graduate and undergraduate students at the University of Virginia mentored by Allison Perkeybile, senior scientist in the College and Graduate School of Arts & Sciences’ Department of Psychology, and Psychology Professors Alev Erisir, Sue Carter and Jess Connelly in collaboration with Prof. Karen Bales of the University of California, Davis. It was funded by the National Institutes of Health and Autism Speaks.