News Briefs – Dec 2016 / Jan 2017

POMEGRANATE EXTRACT PROTECTS THE BRAIN AGAINST ALZHEIMER’S AND DEGENERATION

New research shows that a diet rich in pomegranates has significant positive impacts on the brain health of mice with Alzheimer’s disease. An international team of scientists supplemented the standard diets of mice (that had been bred to provide a model of Alzheimer’s disease) with a 4% extract of pomegranate over a 15-month period. These transgenic mice had demonstrated progressive, age-related, brain decline linked to the build-up of amyloid-beta protein (the main component of the brain plaques found in patients with Alzheimer’s disease) in the brain.

After the introduction of pomegranate, the team observed decreased oxidative stress and neuroinflammation, a reduction in the production of amyloid-beta protein, and improved synaptic plasticity in the brains of the supplemented mice. Synaptic function improved. Compared to other fruits and vegetables, pomegranates contain high concentrations of antioxidant compounds known as polyphenols that apparently play an important role in preventing neurodegenerative disease. It was previously found that giving these polyphenols in isolation, without any of the fruit from which they were extracted, had been unsuccessful and generated unintended consequences. This study shows the synergistic effect of supplementing with polyphenols together with the compounds with which they naturally co-occur. It suggests a novel approach to inhibiting brain decline in Alzheimer’s and other forms of neurodegeneration.

This study was posted under Advanced Online Publications on the site of the journal Oncotarget. The full study report is available at https://tinyurl.com/gs33pbl

VITAMIN E MAY PREVENT PNEUMONIA IN FORMER SMOKERS

Researchers report that administering a small daily dose of 50 mg of vitamin E decreased the overall incidence of pneumonia among males aged between 50 and 69 who were former smokers. The age when the participant had started smoking significantly modified the pneumonia-protective effect of vitamin E. For example, the vitamin had no apparent effect on pneumonia risk for those who had started smoking prior to age 21. Also, vitamin E did not have any significant effect on participants who still smoked heavily or had not been doing exercise. Among participants who started to smoke after age 21 and still smoked moderately, small-dose vitamin E supplementation reduced the incidence of pneumonia by 69% among those who also exercised regularly. Of those who had started smoking after age 21 and who quit later in life, 50 mg of vitamin E daily reduced the incidence of pneumonia by 72% even if they did not exercise and even if they had been heavy smokers.

Because the 1985-1993 Finnish database used in this study included men born in the 1920s and 1930s, this evidence of benefit from vitamin E against community-acquired pneumonia in elderly males should not be generalized to current elderly men in all Western countries. (A dose of 50 mg of vitamin E translates to a dose of 75 I.U.)

This study was published October 3, 2016 in the journal Clinical Interventions in Aging. The full study is available free of charge at https://tinyurl.com/zv69rhf (click on the Download Article button on that page).

LOW VITAMIN D STATUS LINKED TO INCREASED DEPRESSIVE SYMPTOMS

A new study has found that a low vitamin D level is associated with higher levels of negative and depressive symptoms. (Low vitamin D has in the past been linked to increased disease severity in psychotic disorders.) From inpatient and outpatient clinics, the scientists recruited some patients with symptoms that were assessed by special tools (called Positive and Negative Syndrome Scale and the Calgary Depression Scale for Schizophrenia). More volunteers were recruited via assessment by a cognitive test battery that included processing speed, verbal learning, verbal memory, and executive function tests. Low vitamin D levels were found to be significantly associated with increased negative and depressive symptoms. Also there was an association between vitamin D deficiency and cognitive impairments in processing speed and verbal fluency. The team is now running studies investigating potential associations between vitamin D levels and brain structures, which will be measured by magnetic resonance imaging (MRI).

This research was presented October 21, 2016 at the International Early Psychosis Association meeting in Milan. It has not yet been journal-published.

TIMING OF DAILY WALK IMPROVES BLOOD SUGAR IN DIABETICS

New research suggests that people can better manage their Type 2 diabetes if they walk after meals, which offers the greatest blood sugar-lowering benefits. (Current advice suggests that people with Type 2 diabetes walk at least 30 minutes a day, but no particular time of the day is advised. Controlling post-meal glucose is regarded as critical for diabetics, because it contributes to overall blood-sugar control, reduces cardiovascular risk, and may prevent the need for an increased insulin dose which causes weight gain.)

The researchers asked some of 41 patients with Type 2 diabetes to walk for thirty minutes a day and the rest to walk for 10 minutes after each of three daily meals. The patients were fitted with accelerometers that measured their physical activity, as well as devices that measured their blood sugar every five minutes. Post-meal blood sugar levels dropped 12% on average when the participants followed the walking-after-meals advice compared to walking at any time of the day. Most of this average effect came from the highly significant 22% reduction in blood sugar when walking after evening meals, which were the most carb-heavy, and which were ordinarily followed by the most sedentary time.

This study was released October 17, 2016, ahead of later publication in the journal Diabetologia. The full-text study is available at https://tinyurl.com/gnyegmv free of charge.

ANTIOXIDANT N-A-C COMPOUND MAY HELP RESISTANCE TO AGE-RELATED DECLINE

A new study suggests that supplementing with a compound known as N-acetyl-cysteine, or NAC, may help maintain body levels of a compound naturally found in the body that helps resist the toxic cellular stresses of everyday life. Glutathione, or GSH, is a specific detoxification compound that serves as an extremely powerful primary antioxidant (meaning it is produced by the body). Glutathione helps the body to resist the damage of free radicals, toxic stresses, and metabolic declines associated with aging, but its levels decline with age. The decline of glutathione, and consequent decline of natural detoxification pathways, promotes a range of age-related health problems such as cardiovascular disease, diabetes, and cancer. (Glutathione is such an important antioxidant that its existence appears to date back as far as aerobic, or oxygen-dependent, life itself, which is about 1.5 billion years. It is a principal compound to detoxify environmental stresses, air pollutants, heavy metals, pharmaceuticals, and many other toxic insults.)

Scientists have found that supplementing with NAC helps maintain GSH activity. Researchers showed that cells from younger animals are far more resistant to stress than those from older animals, and in young animal cells stress does not cause such a rapid loss of glutathione. The cells from older animals were quickly depleted of glutathione and died twice as fast when subjected to stress. When researchers pretreated older cells with NAC, glutathione levels increased, largely reducing the death of old cells. This suggests that, although glutathione supplements are poorly absorbed*, supplementing with N-acetyl-cysteine may indirectly maintain glutathione, which may inhibit the decline of aging.

This study will be published in the December 2016 issue of the journal Redox Biology. It can be read online now at https://tinyurl.com/jlh9yg8 free of charge.

(*Ed. note: A new form of glutathione, named Setria Glutathione, has been found to be well absorbed orally.)

MECHANISM FOUND, PROOF THAT CRANBERRIES STOP BACTERIAL INFECTIONS

A new study shows that cranberries combat infection via a novel, newly discovered mechanism, thus verifying their long-suspected, infection-fighting capacity and suggesting a greater role for cranberries in the future. (Native Americans have used cranberries for centuries in poultices to treat wounds, and many modern American women use cranberries to help prevent urinary tract infections or UTIs. For years, there was little scientific evidence to back up the medicinal benefits of cranberries in treating UTIs, especially since no one could demonstrate exactly how they might work.)

Recent studies have indicated that cranberries contain compounds such as proanthocyanidins that prevent the bacteria from sticking to urinary tract walls, either by creating a slippery coating that discourages bacteria from sticking, or by changing the bacteria themselves and making them incapable of sticking. But this new study reveals how cranberries really work. They are now believed to disrupt the critical ability of bacteria to communicate, stopping them in their tracks and preventing them from becoming virulent. This communication is a necessary part of the chain of events associated with the spread and severity of chronic bacterial infections. Fruit flies fed cranberry extract were able to fend off bacterial infections, because the extract reduced the severity of any infection, and the flies also lived longer. The study author indicated that cranberries could be part of the arsenal used to control virulent, global infections and potentially minimize depen-dence on antibiotics.

This study was posted online by Scientific Reports, and is now available at https://tinyurl.com/h8m5shq

CT SCAN IRRADIATION COULD CONTRIBUTE TO ALZHEIMER’S

A new study suggests that ionizing radiation encountered in daily life may be a confounding factor in the development of cognitive impairment and in the neurodegenerative disease Alzheimer’s. (More humans today are exposed to ionizing radiation as technicians using nuclear medical equipment and as airline staff during flights. More than 62 million CT scans per year are currently carried out in the U.S. About one third of all diagnostic CT examinations are scans of the head region. This research focuses on possible connections between radiation and cognitive impairments.)

An international consortium has shown that low doses of ionizing radiation can induce molecular changes in the brain that resemble the pathologies of Alzheimer’s. A few head scans in a lifetime should pose no risk, reported the scientists, but some people receive repeated scans. So, using mice, the researchers elucidated molecular alterations caused by chronic, low-dose irradiation in the hippocampus, an important brain region responsible for learning and memory formation and known to be negatively affected in Alzheimer’s. Both low dose rates used seemed capable of inducing Alzheimer’s-like molecular changes. Strik-ingly, the exposure dose for these mice was more than 1000 times smaller than what a patient gets from a single CT scan in the same time interval. The conclusion was that chronic low-dose-rate radiation targets the integration of newborn neurons in existing synaptic wires.

This study was posted online ahead of publication in an upcoming issue of the journal Oncotarget. It can now be read online at https://tinyurl.com/zrx5gdc

STRESS TRIGGERS ABDOMINAL FAT, WEIGHT GAIN

Researchers have discovered that stress causes hormonal changes that cause weight gain. (It is well-known that stress can lead to weight gain as a direct result of the overeating that stress triggers in some people. But this new research identifies a different way in which stress itself, with or without any overeating, packs on the pounds.) The study explains that stress triggers a hormone called Adamts1 that causes fat cells in the body to mature. Not only does this hormone create fat, but it is the visceral type of fat that creates a beer belly, encases internal organs in fat, and increases risk for Type 2 diabetes and heart disease. There are fat deposits scattered around the body that contain many mature fat cells and small numbers of stem cells. The stem cells can differentiate into any type of cell in the body, including fat cells, but until now, no one has known how the process was triggered.

The study found that the trigger is the Adamts1 hormone, which turns stem cells into more fat cells ready to store in fat depots. A high-fat diet also triggers higher Adamts1 production, as well as medications such as prednisone. Whether Adamts1 is triggered by stress hormones or by stress-related eating, the result is the same: weight gain.

This study was published October 25, 2016 in the journal Science Signaling. The full-text report is available at https://tinyurl.com/hqgmg4m for a fee.