Past News Items - August 2008
Return to past News items index
In The News
Study Suggests Relaxation Response Induces Genomic Counter-stress Changes
Cancer Studies Champion Magnolia Compound, Resveratrol
Early-life Nutrition May Ensure Adult Intellectual Functioning
Omega-3 Combo Boosts Memory and Learning
Study Suggests Relaxation Response Induces Genomic Counter-stress Changes
Is it possible that a simple relaxation response can alter the expression of genes? A study appearing in the July 2 issue of the open-access journal PLoS One found the answer to be yes—potentially offering relief to people suffering from health issues ranging from high blood pressure to infertility as well as pain and rheumatological disorders. Research performed in a collaboration between the Benson-Henry Institute for Mind/Body Medicine at Massachusetts General Hospital and the Genomics Center at Beth Israel Deaconess Medical Center suggests that the relaxation response, a physiologic state of deep rest, can influence the activation patterns of genes associated with the body’s response to stress.
Touted as the first comprehensive study of the mind’s effects on gene expression, this investigation focused on the relationship between the relaxation response and the activation or repression of certain genes. The first phase of the study compared gene expression patterns in 19 long-term practitioners of different relaxation response techniques with those of 19 individuals who had never engaged in such practices. The control participants then went through an 8-week training program to determine whether initiating a relaxation response practice would change gene expression over time.
The results were conclusive. Each phase of the study indicated that the relaxation response alters the expression of genes involved in inflammation, programmed cell death, and the body’s handling of free radicals (those molecules produced by normal metabolism that can damage cells and tissues if not properly neutralized). To validate those results, both phases were repeated in 11 participants—6 relaxation response practitioners and 5 non-practitioners. Results showed significantly similar changes in gene expression.
The relaxation response can be elicited by such practices as meditation, deep breathing, and prayer and has been documented in previous studies to alleviate anxiety, heart arrhythmias, high blood pressure, and posttraumatic stress disorder. The researchers of this study hope that their work will generate hypotheses that may later be tested in laboratory and clinical trials.
Genetic Variants Associated With Vitamin B12
A natural compound from magnolia (Magnolia grandifloris) obstructs pathways for cancer growth that were previously termed undruggable, researchers have found. A study performed at Emory University School of Medicine in collaboration with research teams from Hunter College of the City University of New York and Dafna Bar-Sagi at New York University School of Medicine centered on the compound honokiol, a biphenolic compound present in the cones, bark, and leaves of magnolia. The results of the research were published in the July issue of Clinical Cancer Research. Honokiol is used in Japanese and Chinese herbal medicines and was found in 2003 to inhibit tumor growth in mice.
The study’s lead scientists believe that understanding how honokiol works will teach them which cancers are best treated with it. At present, the compound seems most potent against tumors with activated Ras, a family of genes whose mutation stimulates the growth of several types of cancers. Although the Ras family is mutated in close to a third of human cancers, medicinal chemists have considered it an intractable target.
Honokiol's properties could make it useful in combination with other antitumor drugs, because blocking Ras activation would prevent tumors from escaping the effects of these drugs. The compound may work best in making tumors more sensitive to the effects of chemotherapy. Emory University is in the process of licensing honokiol and related compounds to ensure that further human studies may go forward.
In another cancer study, resveratrol, a compound found in red grapes and red wine, was found to suppress abnormal cell function that leads to breast cancer. The research, published in the July issue of Cancer Prevention Research, found that as little as 10 μmol/L of resveratrol could suppress DNA adducts associated with breast cancer. Resveratrol induces an enzyme called quinone reductase, which reduces estrogen metabolites back to inactive form and reduces breast cancer risk. These effects on estrogen are important, as it is known that increased estrogen fuels many types of breast cancer.
Editor’s note: IMCJ will be running articles on both resveratrol and estrogenic breast cancers in the upcoming October-November issue. Stay tuned. . . .
Early-life Nutrition May Ensure Adult Intellectual Functioning
Adults who had improved nutrition in early childhood may score better on intellectual tests, regardless of the number of years they attended school, according to a report in the July issue of Archives of Pediatrics & Adolescent Medicine, one of the JAMA/Archives journals. Previous research has also suggested that poor nutrition in early life is associated with poor performance on cognitive (thinking, learning, and memory) tests in adulthood, so clearly nutrition and early-childhood intellectual enrichment work hand in hand to determine intellectual functioning in adulthood.
For this study, Guatemalan children in 4 villages participated in a trial of nutritional supplementation between 1969 and 1977. Through the trial, some were exposed to atole, a protein-rich enhanced nutritional supplement, while others were exposed to fresco, a sugar-sweetened beverage. Researchers from the Rollins School of Public Health, Emory University, analyzed data from intellectual testing and interviews conducted between 2002 and 2004, when 1448 surviving participants (68.4%) were an average of 32 years old.
Individuals exposed to atole between birth and age 24 months scored higher on intellectual tests of reading comprehension and cognitive functioning in adulthood than those not exposed to atole or who were exposed to it at other ages. This association remained significant when the researchers controlled for other factors associated with intellectual functioning, including years of schooling. Those children who were exposed to atole for the first 3 years of life saw an increase of 0.4 years of schooling compared to those children exposed to fresco. The association was even higher for female participants, whose schooling increased by 1.2 years.
This study was supported by grants from the National Institutes of Health and from the National Science Foundation.
Omega-3 Combo Boosts Memory and Learning
A nutrient cocktail composed of omega-3 fatty acids, uridine, and choline improved memory and learning in gerbils and may have benefits for Alzheimer patients, according to a study performed by researchers at the Massachusetts Institute of Technology (MIT) and published July 7 online ahead of print in the Federation of American Societies of Experimental Biology (FASEB) journal. Animals fed the nutrient mix performed better in maze tests than animals not fed the combination, a result attributed to improved cognitive function.
For the gerbil trial, researchers supplemented the diets of gerbils with uridine (in its monophosphate form, 0.5%) and choline (0.1%), and docosahexaenoic acid (DHA, 300 mg/kg/d) for 4 weeks. Uridine is found in breast milk and synthesized by the body and cannot be obtained from food sources. Choline is found in meats, nuts and eggs, and can also be made by the body. DHA is an omega-3 fatty acid obtained predominantly from marine sources.
At the end of the study, significant increases in phospholipid levels in the brain were observed when the compounds were given together. For example, when the animals were subjected to different maze tests, the combination of supplements produced the best results, indicating enhanced cognitive function.
All 3 dietary supplements used in the study are precursors to the fatty molecules that make up cell membranes, including the membranes of brain cells, which form synapses. Synaptic health plays a vital role in learning and memory functions. The MIT researchers report that gerbils that received all 3 supplements had as much as 70% more phospholipids in the cell membranes than control animals, suggesting the formation of new synapses.
The preliminary results of the clinical trial will be available at the end of the month, at which time researchers hope to discover if similar benefits can be repeated in humans.