NEW YORK (GenomeWeb News) – New research suggests that programs aimed at creating a sense of relaxation and mind-body unity can alter gene expression — including some genes related to stress response.
In a study published online last night in PLoS ONE, a team of American researchers found thousands of gene expression differences between individuals who’d regularly practiced relaxation techniques for several years and those who’d never participated as well as in individuals before and after eight weeks of relaxation training. While it’s too early to draw conclusions about the consequences of these expression differences, the results pave the way for more in-depth studies on the physiological effects of relaxation.
“It was very exciting for me,” said co-senior author Towia Libermann, director of the Beth Israel Deaconess Medical Center’s Genomics Center. Although Libermann has participated in several genomics studies on diseases such as cancer and diabetes, he told GenomeWeb Daily News that this was his first foray into more non-traditional research, melding genomics with a field perceived by some to be “soft science.”
“This is something that’s more on the cutting edge, so to speak,” he said.
Techniques such as yoga, breathing exercises, or meditation have been linked to therapeutic benefits such as decreased blood pressure and lower heart rate. But the physiological changes related to the relaxation response, a mind-body state intended to compensate for the effects of stress, remained poorly studied.
To better understand these changes, the researchers compared 19 healthy individuals who had regularly practiced relaxation techniques such as meditation, yoga, or repetitive prayer for between four and 20 years with 19 age and gender-matched controls who didn’t. They also followed 20 healthy individuals as they embarked on eight weeks of relaxation response training. For each, they measured gene expression from whole blood samples using Affymetrix HG-U133 Plus 2.0 microarrays.
They then verified their results in a second, smaller group, including six long-term practitioners, five non-practicing individuals, and five novices who’d undergone eight weeks of training.
The team found more than 2,200 genes that were expressed differently in relaxation response practitioners — 1,275 that were up-regulated and 934 that were down-regulated. Likewise, eight weeks of relaxation response training altered the expression of 1,561 genes, up-regulating 874 genes and down-regulating 687 others.
And although they found significant differences in gene expression between long- and short-term relaxation practitioners, the researchers also found a shared group of 433 genes with the similar expression patterns in the long- and short-term practitioners.
Genes related to ubiquitination, oxidative phosphorylation, electron transfer, ribosomal function, NF kappa B, RNA metabolism, and stress response pathways were among those whose expression changed in relaxation practitioners.
“Some of the things were definitely not what we’d anticipate,” Libermann noted.
The study also posed new experimental design, bioinformatics, and data analysis challenges, Libermann said. And there were certain limitations that were unavoidable. For instance, the researchers depended to a large extent on self-reported information from individuals about how often they practiced relaxation techniques. In addition, Libermann noted, it’s possible that some individuals in the control group were naturally more relaxed than some in the practitioner group, which could confound the results.
Libermann said the team is currently doing a larger genomic study, collecting more samples over shorter windows from those participating in relaxation response training. Rather than looking at broad changes in gene expression over several weeks, they will compare participants’ gene expression before, during, and after relaxation response sessions.
And while the research so far has focused on healthy individuals, he added, they would eventually like to do studies to help them understand how the relaxation response influences conditions such as obesity, diabetes, and high blood pressure.