A new study has found that elicitation of the relaxation response - a physiologic state of deep rest induced by practices such as meditation, yoga, deep breathing and prayer - produces immediate changes in the expression of genes involved in immune function, energy metabolism and insulin secretion.
The study from investigators at the Benson-Henry Institute for Mind/Body Medicine at Massachusetts General Hospital (MGH) and Beth Israel Deaconess Medical Center (BIDMC) combined advanced expression profiling and systems biology analysis to both identify genes affected by relaxation response practice and determine the potential biological relevance of those changes.
"Many studies have shown that mind/body interventions like the relaxation response can reduce stress and enhance wellness in healthy individuals and counteract the adverse clinical effects of stress in conditions like hypertension, anxiety, diabetes and aging," said Herbert Benson, MD, director emeritus of the Benson-Henry Institute.
"Now for the first time we've identified the key physiological hubs through which these benefits might be induced," he stated.
Towia Libermann, PhD - director of the Beth Israel Deaconess Medical Center (BIDMC) Genomics, Proteomics, Bioinformatics and Systems Biology Center and co-senior author of the study - added, "Some of the biological pathways we identify as being regulated by relaxation response practice are already known to play specific roles in stress, inflammation and human disease. For others, the connections are still speculative, but this study is generating new hypotheses for further investigation."
The current study examined changes produced during a single session of relaxation response practice, as well as those taking place over longer periods of time.
The study enrolled a group of 26 healthy adults with no experience in relaxation response practice, who then completed an 8-week relaxation response training course.
The results revealed significant changes in the expression of several important groups of genes between the novice samples and those from both the short- and long-term sets, with even more pronounced changes in the long-term practitioners.
A systems biology analysis of known interactions among the proteins produced by the affected genes revealed that pathways involved with energy metabolism, particularly the function of mitochondria, were upregulated during the relaxation response. Pathways controlled by activation of a protein called NF-?B - known to have a prominent role in inflammation, stress, trauma and cancer - were suppressed after relaxation response elicitation. The expression of genes involved in insulin pathways was also significantly altered.
After eight weeks of performing the technique daily, the volunteers gene profile was analysed . Clusters of important beneficial genes had become more active and harmful ones less so.
The boosted genes had three main beneficial effects: improving the efficiency of mitochondria, the powerhouse of cells; boosting insulin production, which improves control of blood sugar; and preventing the depletion of telomeres, caps on chromosomes that help to keep DNA stable and so prevent cells wearing out and ageing.
Clusters of genes that became less active were those governed by a master gene called NF-kappaB, which triggers chronic inflammation leading to diseases including high blood pressure, heart disease, inflammatory bowel disease and some cancers.
By taking blood immediately after before and after performing the technique on a single day, researchers also showed that the gene changes happened within minutes.
For comparison, the researchers also took samples from 26 volunteers who had practised relaxation techniques for at least three years. They had beneficial gene profiles even before performing their routines in the lab, suggesting that the techniques had resulted in long term changes to their genes.
"It seems fitting that you should see these responses after just 15 to 20 minutes just as, conversely, short periods of stress elevate stress hormones and other physiological effects that are harmful in the long term," says Julie Brefczynski-Lewis of West Virginia University in Morgantown, who studies the physiological effects of meditation techniques. "I hope to see these results replicated by other groups."
"We found that the more you do it, the more profound the genomic expression changes," says Benson. He and his colleagues are now investigating how gene profiles are altered and whether these techniques could ease symptoms in people with high blood pressure, inflammatory bowel disease and multiple myeloma, a type of bone marrow cancer.
Manoj K. Bhasin, PhD, co-lead author of the study and co-director of the BIDMC Genomics, Proteomics, Bioinformatics and Systems Biology Center, noted that these insights should provide a framework for determining, on a genomic basis, whether the relaxation response will help alleviate symptoms of diseases triggered by stress and developing biomarkers that may suggest how individual patients will respond to interventions.
Benson stresses that the long-term practitioners in this study elicited the relaxation response through many different techniques - various forms of meditation, yoga or prayer - but those differences were not reflected in the gene expression patterns.
