News Briefs – June 2015
Michael Downey May 28, 2015Antioxidant Therapy May Help Treat Concussion Injuries
A researcher has found that antioxidants may play a key role in reducing the long-term effects of concussions and could potentially offer a unique new approach for treatment. (Common among athletes and soldiers, it is estimated that 3.4 million concussions occur each year in the US. The development of a readily available oral supplement would have the potential to improve brain function in a percentage of concussion sufferers.)
This study adds to recent findings that concussions can lead to chronic traumatic encephalopathy (CTE), a disease associated with long-term brain damage and behavioural symptoms including memory loss, impulsive behaviour, depression, and aggression. The number of retired athletes and veterans diagnosed with CTE has climbed in recent years. The researcher reported that concussions can contribute to long-term changes within the brain and these changes are the result of cell death, which might be caused by oxidative stress.
This study showed that antioxidants such as lipoic acid can reduce the long-term deficits when given after a concussion. Rats were divided into three groups: a non-concussed control group, a group that experienced concussive injury, and another concussed group that received lipoic acid supplementation. Seven days after concussion, rats were tested for seemingly impulsive behaviour through an elevated maze. The rats exposed to concussion without lipoic acid had increased impulsive behaviour, and spent more time exploring open spaces indicative of risk-taking behaviour, which shows underlying brain damage. Analysis of brains of the group receiving lipoic acid supplementation showed markedly decreased impulsive behaviour. (This makes sense because lipoic acid works to help reduce toxic free radicals that can damage cells.)
The study results were presented in Boston on April 1, 2015 at Experimental Biology 2015.
Vitamin E Can Prevent Harm Caused by Oxidative Stress
Researchers have uncovered the mechanism through which oxidative stress reduces immunity and drives disease, and they have found that, at least in mice, high doses of vitamin E reverse these effects on the immune system. Oxidative stress is implicated in many diseases and may even be a cause of some. It is believed that oxidative stress suppresses the normal immune response, but the mechanism has never been clear. (Factors such as UV radiation, air pollution, smoking, alcohol consumption, and infections increase oxidative stress in the body, which in turn weakens the immune system and allows infections to become chronic or potentially serious.)
When viruses or other pathogens enter the body, certain immune cells known as T cells proliferate rapidly. T cells known as CD8+ cells eliminate the virus by killing the human cells it has infected. T cells known as CD4+ cells coordinate the immune response to all kinds of pathogens. However, this study has shown that this immune response does not work if significant oxidative stress is damaging the T cells and depriving the body of the repair enzyme (called Gpx4) it needs to repair oxidative damage to the T cell membrane. The T cells die off, allowing the infection to become chronic.
The team tested mice whose immune cells lacked the T cell repair enzyme (Gpx4) and found that the T cells were protected against cell death by high doses of vitamin E and could multiply successfully and beat the infection. The doses were 10 times higher than in standard lab mouse food, but mouse levels cannot be translated into human terms without extensive research. The researchers noted that the type of death found in T cells under oxidative stress is the same as the death of some kinds of cancer cells when treated with cancer cell-killing (cytostatic) drugs. The team suggested that vitamin E supplements may be useful in supporting immunity at those times when the body is under oxidative stress such as infection or excess UV radiation.
This study was published in the April 6, 2015 issue of the Journal of Experimental Medicine. It is available at https://tinyurl.com/nwpyyee for a fee.
Saffron Supplements Prevent Sports-Related Muscle Pain Better than Drugs
A new report indicates that daily saffron supplements are more effective at preventing muscle weakness and pain following strenuous exercise than anti-inflammatory drugs. This type of weakness and pain is delayed-onset muscle soreness, or DOMS, which often occurs after unaccustomed or unusual exercise. It can reduce subsequent exercise performance.
The study showed that two saffron carotenoids, crocin and crocetin, may have anti-inflammatory and pain-relieving properties that prevent DOMS. (Past studies have shown that the popular spice saffron, produced from the flower of the Crocus sativus, contains beneficial compounds called carotenoids which are associated with cancer and heart-disease prevention.)
Researchers tracked 39 men, 12 of whom took daily capsules containing 300 milligrams of powdered saffron, one week before and three days after a strenuous exercise session. Another 12 men took indomethacin, a nonsteroidal anti-inflammatory drug (NSAID), three times a day. Fifteen others received placebo pills. Those given a placebo reported severe muscle pain for three days. The drug group experienced minor pain at 24 hours that disappeared after 72 hours. But the saffron group was pain-free for three days after the exercise session.
This study was presented April 14-19, 2015 at the 24th annual meeting of the American Medical Society for Sports Medicine in Hollywood, Florida. It is available on the website of the Clinical Journal of Sports Medicine at https://tinyurl.com/m6ztkj4 without cost.
Diabetes and Depression Linked to High Risk of Dementia
Scientists have found that depression and Type 2 diabetes are each associated with increased dementia risk. And they found that the risk of dementia is more than double for those who have both depression and diabetes. Over six years, the researchers analyzed dementia risk among individuals with depression, Type 2 diabetes, or both. These were then compared with individuals who had neither condition in a group of over 2.4 million people aged 50 and older and free from dementia at the start of the study. Overall, 19.4% had diagnosed depression, 9.1% had Type 2 diabetes, and 3.9% had both diabetes and depression.
During the six-year study, 2.4% of individuals developed dementia. The results indicated that Type 2 diabetes alone was linked to a 20% greater risk for dementia. Depression alone was linked to an 83% greater risk. Having both depression and Type 2 diabetes was linked to a 117% greater risk of depression. These links appeared to be even greater among participants younger than 65. It is important to remember that epidemiological studies do not prove that such associations are cause-and-effect.
This study was released online April 15, 2015 by JAMA Psychiatry, which will publish it in a future issue. It can now be read online at https://tinyurl.com/n5c3qpg free of charge.
Excess Sugar and Carbs Behind Obesity Trend – Not Lack of Exercise
Excessive intake of sugar and carbohydrates, not physical inactivity, are behind the overall increase in obesity in modern society, reports an article in a prestigious sports journal.
Regular exercise may be important for warding off serious diseases such as diabetes, heart disease, and dementia, write the authors, but commonly calorie-laden diets now generate more ill-health than physical inactivity, alcohol, and smoking combined. Evidence now suggests that up to 40% of those within a normal weight (BMI) range will still have harmful metabolic abnormalities typically associated with obesity. Few people realize this, and many wrongly believe that obesity is entirely due to lack of exercise, a perception that is firmly rooted in corporate marketing, write the authors. They describe the public relations tactics of the food industry as “chillingly similar to those of Big Tobacco” which deployed denial and doubt to dissuade the public that smoking was linked to lung cancer.
The authors add that public health messages have focused on maintaining a healthy weight through calorie counting, when in fact it is the source of the calories that matters. Sugar calories promote fat storage and hunger. The prevalence of diabetes increases 11-fold for every 150 additional sugar calories consumed daily, compared with the equivalent amount of calories consumed as fat. (Recent research indicates that dietary carbohydrate increases features of metabolic syndrome whether weight gain is involved or not. Other research suggests that carbohydrate loading ahead of intense exercise is a health risk and possibly, a diabetes risk.) The article concludes that, “You cannot outrun a bad diet.”
This editorial was released April 22, 2015 on the website of the British Journal of Sports Medicine. It can be accessed online now at https://tinyurl.com/q3w77ns with fee payment.
Did You Know…?
People with osteoporosis have a 1.76-fold higher risk of developing sudden deafness than those without this bone disease, according to a study published in the Journal of Clinical Endocrinology and Metabolism.
Statin Drugs Raise Diabetes Risk by 46 Percent
A study has found a new link between cholesterol-lowering statin drugs and diabetes, reporting a 46% increase in the risk of developing diabetes among statin users. (Previous studies have suggested this association, but have been inconclusive or limited in scope. This new study is the most rigorous epidemiological study to date.)
Researchers tracked connections between statin treatment and development of Type 2 diabetes, or deteriorated blood sugar control, in 8,749 non-diabetic men over a 6-year period. They found that patients treated with statin drugs were 46% more likely to develop diabetes, even after discounting such potentially confounding factors as age, weight, physical inactivity, smoking, alcohol intake, and family history of diabetes.
The association between statin use and increased diabetes risk is likely related directly to statins decreasing both insulin sensitivity and secretion, the study found.
This study was published in the May 2015 issue of the journal Diabetologia. The full-text report can be downloaded, only as a PDF, at https://tinyurl.com/n8k4pff free of charge.
Even Modest Exercise Increases Lifespan
A new analysis of six past studies has found that staying active, even only modestly, confers major longevity benefits. During many years of follow-up, people who did less than the minimum recommended amount of physical activity still had a considerable decrease in risk of death compared to people who did no activity. These findings determined that there is a substantial benefit from following the 2008 Physical Activity Guidelines for Americans, which recommend either a minimum of 150 minutes of moderate-intensity, or 75 minutes of vigorous-intensity, activity per week. They also suggested an additional benefit for those who achieve more than double the exercise minimum.
Researchers pooled data on more than 660,000 men and women in the U.S. and Europe from previous studies, and half the studies had tracked participants for more than 14 years. People who did less than the recommended minimum of activity were still 20% less likely to die during the studies than people who were not active at all. Mortality risk was 31% lower for people who did one to two times the recommended minimum, and 37% lower for those who did two to three times the recommended minimum activity.
Mortality risk seemed to level off at the high level of three to five times the recommended minimum amount of exercise; this high level is equivalent to walking for a weekly total of seven hours or running for a weekly total of two hours 15 minutes. The results were similar for deaths from any cause or deaths specifically from cardiovascular disease or cancer. The team adjusted for mortality risk factors such as body mass-index and smoking, but could not adjust for diet; so different diets could have played some role. Just one hour of brisk walking, or 30 minutes of jogging or biking, over the course of a week is enough to move out of the inactive category into the “substantial benefit” category.
The study found that volume of activity, rather than intensity, drives longevity benefit. (But another study from the same journal issue found that vigorous activity was more strongly linked to a decreased mortality than moderately intense activity; so further research is needed to determine whether associations between physical activity and mortality differ by specific activities.)
This study was released on April 6, 2015, and will be published in a later issue of JAMA Internal Medicine. The report is at https://tinyurl.com/pq8jd2h for purchase.
Folic Acid May Help the Elderly Survive Heat Waves
According to researchers, supplemental folic acid (vitamin B9) can enhance blood vessel dilation in older adults, suggesting that they may be an inexpensive alternative for helping older adults to increase skin blood flow during heat waves and reduce the risk of cardiovascular events such as strokes and heart attacks. When older adults are exposed to excessive heat, their bodies are not able to increase skin blood flow to promote sweat and cool the body to the same extent that young persons do, and as a consequence, older adults are at greater risk for cardiovascular events, such as heart attack and stroke, during environmental heat waves. This is due, in part, to aged blood vessels that cannot produce enough nitric oxide, the blood vessel-relaxing molecule produced using an enzyme that requires tetrahydrobiopterin, or BH4. As people age, BH4 bioavailability decreases. For this whole-body heating study, elderly humans took 5 milligrams of folic acid or a placebo once daily for six weeks. It was shown that folic acid increased nitric oxide production by increasing BH4. This study was published online in the journal Clinical Science and is now available at https://tinyurl.com/p73494a for purchase.
Western Diet Shown to Increase Colon Cancer Risk in Two Weeks
A new study has found that when African-Americans and rural South Africans swapped diets for two weeks, there was a surprisingly sudden shift in the risk of colon cancer for each group: the normally higher risk among African-Americans decreased and the normally lower risk among rural South Africans increased. (Colon or colorectal cancer is the third most common cancer worldwide and the fourth most common cause of cancer death. Rates of colon cancer are much higher in the western world than in Africa and the Far East. Yet in the U.S, the highest rates of all occur among African-Americans. The traditional African diet contains more soluble fiber and less animal protein and fat.)
For the study, 20 African-American and 20 rural South African volunteers aged 50-65 spent two weeks under controlled conditions where they ate only the normal diet of the opposite group. The researchers examined fecal and colon content sampled from each participant at the start and end of the swap. Participants also underwent colonoscopy exams at the study start and end. The study took place at a university site in the U.S. and a lodging facility in South Africa, allowing the researchers to control the experiment.
The study leader indicated that the higher animal protein and fat, along with lower soluble fibre, in the African-American diet increases colon cancer risk. Despite the very brief period of the diet swap, just two weeks, each group took on the indicators for colon cancer risk of the other group (levels of fibre fermentation, butyrate production, turnover of cells in the gut lining, markers of metabolic activity in gut microbes, inflammation, and intestinal bacteria makeup).
This study was published in the April 28, 2015 issue of Nature Communications and is now available at https://tinyurl.com/nt9ksna for a fee.
Turmeric May Help Treat Oral Cancer
A study has found that turmeric, the yellow spice commonly used in Indian and Asian cooking, may play a therapeutic role in oral cancers which are associated with human papillomavirus (HPV). One of the key active compounds in turmeric is an antioxidant called curcumin, which appears to quell the activity of HPV. (HPV is a virus that promotes development of cervical and oral cancer. There is no cure. Turmeric has antiviral and anti-cancer properties.) The research group found that curcumin turns down the expression of HPV in infected oral cancer cells by downregulating levels of inflammation (as shown by reduced levels of cellular transcription factors). These findings could suggest a new therapeutic role for curcumin in cancer control. Researchers concluded that the use of turmeric and other antioxidants may be good for health in general and HPV-related oral cancers in particular.
This study was published online April 22, 2015 by the journal ecancermedicalscience. The full report can be read at https://tinyurl.commom6gso free of charge.