The Medical News recently posted and article entitled: Research suggests potential new treatment for anxiety disorders and depression.
The article reviews the study A New Role for FGF2 as an Endogenous Inhibitor of Anxiety, which was published by The Journal of Neuroscience on May 13, 2009.
The article reminds us that “(p)revious human studies…showed that people with severe depression had low levels of FGF2 and other related chemicals. However, it was unclear whether reductions in FGF2 were the cause or effect of the disease.”
FGF2 wears several hats in the human body. According to Wikipedia, FGF2 plays a role in “excessive anxiety…wound healing…tumor development.” Further, FGF2 is “a critical component of human embryonic stem cell culture…”
The researchers studied rats that were genetically bred for high anxiety and low anxiety. They “found lower FGF2 levels in rats bred for high anxiety compared to those bred for low anxiety.”
The study’s lead researcher, Javier Perez, PhD, at the University of Michigan, states that “We have discovered that FGF2 has two important new roles: it’s a genetic vulnerability factor for anxiety and a mediator for how the environment affects different individuals. This is surprising, as FGF2 and related molecules are known primarily for organizing the brain during development and repairing it after injury.”
In other words, persons with genetically low levels of FGF2 are at higher risk for anxiety.
The researchers also looked at the complex interplay between the environment and FGF2 levels.
Very interestingly, “Perez and colleagues found that giving the high-anxiety rats a series of new toys reduced anxiety behaviors and increased their levels of FGF2.” So, changing and enriching the environment has an effect of anxiety reduction and increasing FGF2 levels.
Perhaps, then, genetically low levels of FGF2 might be compensated for in part if the environment is made interesting, fun, and relatively low stress.
On the other hand, according to The Medical News, the researchers “found that FGF2 treatment alone reduced anxiety behaviors in the high-anxiety rats.”
How does FGF2 specifically impact anxiety? The Medical News summarizes the studies findings:
“Finally, the findings suggest that part of FGF2’s role in reducing anxiety may be due to its ability to increase the survival of new cells in a brain region called the hippocampus….Although the researchers found that high-anxiety rats produced the same number of new brain cells as low-anxiety rats, they found decreased survival of new brain cells in high-anxiety rats compared to low-anxiety rats. However, FGF2 treatment and environmental enrichment each restored brain cell survival.”
Thus, in one of life’s many cruel twists of fate, people who are vulnerable to anxiety because of low levels of FGF2, also suffer from increased levels of cell death at times of stress. The cell death makes them less able to cope with the environmental and other precipitants to their anxiety. Those who would benefit the most from increased brain cell growth and survival are deprived of it due to genetically low levels of FGF2.
This study also sheds a very engaging light onto the age old question of nature versus nurture. It would seem, from this study, that neither nature nor nurture by themselves can adequately explain why some people are more anxious than others. Rather, it is a complex interaction of both genetic and environmental factors.
Future studies might be able to identify new medications to bolster levels of FGF2 as well as to identify changes in a person’s lifestyle and environment that support FGF2 levels and the consequent improvements in cell growth and anxiety reduction.