Psychology researchers at The University of Texas at El Paso are advancing the understanding of the biological causes of depression, which is a major cause of disability that impacts about 280 million people globally. In a study printed this April in the Journal of Affective Disorders, UTEP psychologist Sergio Iñiguez, Ph.D., and his colleagues make a case that prairie voles, small rodents found throughout the central United States and Canada, can be effectively used as animal models for the study of clinical depression.The authors argue that prairie voles, small rodents found in the central United States and Canada, can be used as effective animal models to study clinical depression.
“The results of this research are significant because we have demonstrated, for the first time, that prairie voles exhibit some of the key symptoms of depression after being exposed to chronic stress — just like humans,” Iñiguez stated. “This is exciting because it means we can now use this animal model to potentially uncover the biological factors that contribute to illnesses such as depression and anxiety.”
The UTEP study focuses on the impact of “bullying”Researchers analyzed the behavioral patterns of voles by observing the effects of bullying on individual male voles for ten days, resulting in what Iñiguez describes as “social defeat stress.”
Iñiguez noted that the bullied voles displayed changes in body weight, performed poorly on spatial memory tests, and exhibited less sociable behavior towards other voles compared to those who were not bullied. Additionally, the bullied voles showed no preference for sugar water when given the choice between regular water and sugar water, indicating a loss of pleasure in regular activities, known as anhedonia.Iñiguez and his team found that engaging in harmful social interactions activated the voles’ stress response and increased the risk of symptoms similar to depression in humans. Despite the defining characteristics of depression, such as sadness, lack of pleasure in normal activities, and disruptions in sleep and eating patterns, researchers still do not have a complete understanding of its causes.The challenges of identifying the biological factors contributing to depression are complicated by the ethical considerations surrounding neurobiological research in humans, according to Iñiguez. While rats and mice are common subjects in psychology research, prairie voles have attributes more similar to humans, such as monogamous relationships and parenting behaviors, making them well-suited for studies. The study is led by psychology doctoral student Minerva Rodriguez, who highlights the significance of these special animals in advancing understanding of the condition.The article states that the researchers are exploring aspects of depression in prairie voles, as their unique social behaviors open up new possibilities for studying social stress-induced depression at a neurological level. Future studies will focus on how the voles recover from depression-like experiences and their response to antidepressant medications such as Prozac or ketamine. This project is supported by a grant from the National Institutes of Health.
