Delving into the DNA

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Many practices and traditions, mostly in the orient, combine physical and mind control disciplines.

These practices are known to bring about calmness, reduce anxiety and the perception of stress, relieve depression or help people cope with chronic disease. While these methods are associated with control of hypertension, insomnia, arthritis and many stress induced conditions, the mechanism by which the reported benefits arise has not been understood.

Ivana Buric, Miguel Farias, Jonathan Jong, Christopher Mee and Inti A Brazil, working in Coventry University, UK, Radboud University, Nijmegen, Netherlands and Antwerp University, Belgium have looked into how these practices may affect the body at the cellular level.

Their report, in the journal, Frontiers in Immunology, finds that mind-body interventions suppress the presence of a main factor that is known to facilitate the reaction of cells to stress, which leads to inflammation-related diseases.

While there have been studies of the effects of MBI on the parts of the brain that control things like emotions, learning and memory, these have not been conclusive, the paper says.

However, powerful techniques to study how genes, or portions of the genetic record in the interior of cells become effective, are now available and there are several reports of analyses of gene expression and MBI research, the paper says.

The centre, called the nucleus of living cells, contains a long, chain molecule, the DNA, which consists of millions of segments. Each segment contains the code for the assembly of a unique protein. Some proteins go to make up body tissue, like muscle tissue, or hair or skin.

Others, like haemoglobin, can play a role almost like an organ, which has a specific function. And yet other proteins are messengers that go from cell to cell or from one part of a cell to another, to start or stop things that the cells do. As proteins have complex and unique shapes, or profiles, they can act as very secure “keys” to fit specific “keyholes” in cells, to set in motion various sequences, including the release of other proteins.

When cells create proteins, the method is that a part of the DNA, the part that codes for that protein, is copied and transferred to another part of the cell where the protein is assembled. One group of messenger proteins, the transcription factors, specialise in setting in motion the process of copying a part of the DNA, for creation of proteins.

A study of the effect of individual genes, however, is not feasible, as there are so many and because genes generally work, not by themselves, but in in groups. Genes are hence studied using statistical methods and computer controlled artificial intelligence systems, to identify which ones are associated with the same pathways and related functions.

In the context of research on MBIs, the paper says that the most studied transcription factor, or the protein that sets in motion the process of protein assembly, is one called nuclear factor kappa B (NF-kB).

This factor gets released when the organism is stressed, to set in motion the “self-defence” processes in the cell. NF-kB is found in almost all kinds of animal cells and the stress could be the presence of the so called, “free radicals” (which are suppressed by antioxidants), heavy metal poisoning, ultra violet radiation, responses to bacteria or viruses or other stress signalling proteins.

When the messengers that signal attack or danger make contact with the cell, NF-kB — a “rapid acting” transcription factor — gets released because it is present in the cell and need not be generated. The cells then respond by releasing proteins that bring about inflammation.

These proteins set in motion a “cell survival” response or could lead to cell proliferation, to combat the threat. And to prevent run-away cell response, NFkB also sets in motion a substance that suppresses NF-kB itself, to turn off the emergency alert.

Errors in the regulation of NF-kB, however, can lead to continued inflammation, and this leads to autoimmune diseases, where the body attacks itself, like bowel disease or arthritis. As NF-kB brings about replication of cells, it can cause cancers and it even encourages some viruses to multiply.

While the release of NFkB helps the body cope when there is a threat or challenge, modern living often creates continuous stressful conditions and excess release of NFkB.

“Chronic inflammation is associated with increased risk for some types of cancer, neurodegenerative diseases, asthma, arthritis, cardiovascular diseases, and psychiatric disorders,” the paper says. As MBIs are known to help stressful conditions, there is a hypothesis that MBIs can turn around, or reverse, the expression of genes involved in inflammatory reactions that are induced by stress, the paper says.

To see if this actually happens, the researchers reviewed available information about the changes in gene expression that occur when persons undertake MBI practices. World-wide publications were scanned and 716 articles were identified and analysed, to be left with 18 studies and 846 participants, which were statistically reliable.

The MBI practices studied include Asian Qigong (reading of texts and light physical practice), sudarshan kriya (yogic breathing practice), pranayama (breath control), kirtan kriya meditation, Tai Chi, Iyengar yoga (a form of Hatha yoga with emphasis on precise alignment and breath control in each posture), Relaxation Response and Mindfulness practice. The studies were carried out by creating groups of practitioners of the MBIs, along with groups of comparable persons who did not practice the MBI.

Which genes were active in different types of cells in the two groups was then ascertained.

A study with Qigong, for instance, used neutrophils, the most common type of white blood corpuscles, which are crucial in the defence against infection —12,000 genes were studied and it was found that 132 genes were suppressed and 118 were promoted.

“Some of the differentially expressed genes have common functions, which suggests that Qigong enhances immunity, down regulates cellular metabolism, and delays cell death,” the paper says. Studies with sudarshan kriya, pranayama, yogic meditation, mindfulness and Tai Chi led to similar results. One study explored the effects of three months of Iyengar yoga on inflammatory processes in breast cancer survivors with fatigue — 282 genes were found to be promoted and 153 were suppressed in the yoga group, as compared to the health education control group.

The majority of the genes suppressed were the ones associated with fatigue in cancer patients. Iyengar yoga was found both to reduce the activity of NF-kB, the key regulator, and to increase the activity of cell features that reduced inflammation.

One study was with patients of Irritable Bowel Syndrome and Inflammatory Bowel Disease. The researchers explored the value of Relaxation Response — breath focus, imagery, mindful awareness, and yoga.

They found that nine weeks of hour-long weekly sessions with 20 mins of daily home practice brought remission of pain and anxiety and a rise in the quality of life.

In the IDB group, 1059 genes were found to have changed — and these were related to improvements in inflammatory response, cell growth, multiplication of cells, and the effect of oxidising “free radicals”. Another 119 genes were related to cell-cycle regulation and DNA damage.

The authors caution that the studies are still not exact and do not deal with the possible effects of other factors, like diet, sleep, exercise or environment.

However, “the results of 18 studies that used gene expression analysis in research on meditation and related MBIs have overall found down regulation of NF-kB-targeted genes, which can be understood as the reversal of the molecular signature of the effects of chronic stress,” the paper says.

The writer can be contacted at response@simplescience.in

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