CNO Report 189
Release Date 15 SEP 2014
Draft Report Compiled by
In This Issue:
- Drinking tea reduces non-CV mortality by 24 percent
- Fruit consumption cuts CVD risk by up to 40 percent
- Can action movies make you fat?
- Spinach extract decreases cravings, aids weight loss
- Estrogen increases cannabis sensitivity
- Intestinal barrier damage in multiple sclerosis
- Study: Oxidized LDL might actually be ‘good guy’
- Flour identified as the main cause of occupational asthma in France
- Fish oil may help curb seizure frequency in epilepsy
- Breast milk may be protective against devastating intestinal disorder
- New study: Emerging research indicates mangos may lower blood sugar in obese adults
- Gut microbes determine how well the flu vaccine works
- Not enough vitamin B1 can cause brain damage
Drinking tea reduces non-CV mortality by 24 percent
Barcelona, Spain – Sunday 31 August 2014: Drinking tea reduces non-cardiovascular mortality by 24%, reveals a study in 131 000 people presented at ESC Congress today by Professor Nicolas Danchin from France.
Professor Danchin said: “If you have to choose between tea or coffee it’s probably better to drink tea. Coffee and tea are important components of our way of life. Their effects on cardiovascular (CV) health have been investigated in the past with sometimes divergent results. We investigated the effects of coffee and tea on CV mortality and non-CV mortality in a large French population at low risk of cardiovascular diseases.”
The study included 131 401 people aged 18 to 95 years who had a health check up at the Paris IPC Preventive Medicine Center between January 2001 and December 2008. During a mean 3.5 years follow up there were 95 deaths from CV and 632 deaths from non-CV causes. Coffee or tea consumption was assessed by a self-administered questionnaire as one of three classes: none, 1 to 4, or more than 4 cups per day.
The researchers found that coffee drinkers had a higher CV risk profile than non-drinkers, particularly for smoking. The percentage of current smokers was 17% for non-drinkers compared with 31% in those who drank 1 to 4 cups per day and 57% in those who drank more than 4 cups per day.
Non-coffee drinkers were more physically active, with 45% having a good level of physical activity compared to 41% of the heavy coffee drinkers. Professor Danchin said: “This is highly significant in our large population.”
Heavy drinkers of coffee were older than the non-drinkers, with a mean age of 44 compared to 40 years. The differences in blood pressure were small, with heavy coffee drinkers having a slightly lower systolic blood pressure (SBP) and higher diastolic blood pressure (DBP) compared to non-drinkers when adjusted for age.
Tea drinkers had the reverse profile of coffee drinkers, with consumers having a better CV risk profile than non-consumers. One-third (34%) of the non-drinkers of tea were current smokers compared to 24% of those who drank 1-4 cups per day and 29% of those who drank more than 4 cups. Physical activity increased with the number of cups of tea per day from 43% in the moderate tea drinkers to 46% in the heavy drinkers.
Tea had a more marked effect on blood pressure than coffee, with a 4-5 mmHg decrease in SBP and 3 mmHg decrease in DBP in the heavy tea drinkers, compared to non-drinkers, when adjusted for age.
Professor Danchin said: “Overall we tend to have a higher risk profile for coffee drinkers and a lower risk profile for tea drinkers. We also found big differences with gender. Men tend to drink coffee much more than women, while women tend to drink more tea than men.”
Coffee showed a trend for increasing CV mortality in the heavy compared to non-drinkers but the effect was not significant. Coffee significantly increased non-CV mortality but the increased risk disappeared when the effect was adjusted for smoking. Professor Danchin said: “The trend for higher mortality in coffee drinkers is probably largely explained by the fact that there are more smokers in the group who drink a lot of coffee.”
There was a trend for tea drinking to decrease CV mortality but the effect was not quite significant after adjusting for age, gender and smoking. But tea significantly lowered the risk of non-CV death, with a hazard ratio of 0.76 for tea drinkers compared with no tea at all.
Professor Danchin said: “Tea drinking lowered the risk of non-CV death by 24% and the trend towards lowering CV mortality was nearly significant. When we extended our analysis to 2011 we found that tea continued to reduce overall mortality during the 6 year period. Interestingly, most of the effect of tea on non-CV mortality was found in current or ex-smokers, while tea had a neutral effect in non-smokers.”
He concluded: “Tea has antioxidants which may provide survival benefits. Tea drinkers also have healthier lifestyles so does tea drinking reflect a particular person profile or is it tea, per se, that improves outcomes – for me that remains an open question. Pending the answer to that question, I think that you could fairly honestly recommend tea drinking rather than coffee drinking and even rather than not drinking anything at all.”
Fruit consumption cuts CVD risk by up to 40 percent
Barcelona, Spain – Monday 1 September 2014: Daily fruit consumption cuts the risk of cardiovascular disease (CVD) by up to 40%, according to research presented at ESC Congress today by Dr Huaidong Du from Oxford, UK. The findings from the seven year follow-up study of nearly 0.5 million people in the China Kadoorie Biobank found that the more fruit people ate, the more their risk of CVD declined.
Dr Du said: “CVD, including ischaemic heart disease (IHD) and stroke, is the leading cause of death worldwide. Improving diet and lifestyle is critical for CVD risk reduction in the general population but the large majority of this evidence has come from western countries and hardly any from China.”
She added: “China has a different pattern of CVD, with stroke as the main cause compared to western countries where IHD is more prevalent. Previous studies have combined ischaemic and haemorrhagic stroke probably due to the limited number of stroke cases in their datasets. Given their different physiology and risk factors, we have conducted the first large prospective study on the association of fruit with subtypes of stroke in Chinese adults from both rural and urban areas.”
The current study included 451 681 participants with no history of CVD and not on anti-hypertensive treatment at baseline from the China Kadoorie Biobank(1) conducted in 10 different areas of China, 5 rural and 5 urban. Habitual consumption of fruit was recorded at baseline according to five categories: never, monthly, 1-3 days per week, 4-6 days per week, daily.
Over the seven year follow up period there were 19 300 cases of IHD and 19 689 strokes (14 688 ischaemic and 3562 haemorrhagic). Some 18% of participants consumed fruit daily and 6.3% never consumed fruit. The average amount of fruit eaten by the daily consumers was 1.5 portions (~150g) (2).
The researchers found that compared to people who never ate fruit, those who ate fruit daily cut their CVD risks by 25-40% (around 15% for IHD, around 25% for ischaemic stroke and 40% for haemorrhagic stroke). There was a dose response relationship between the frequency of fruit consumption and the risk of CVD (see figure).
Dr Du said: “Our data clearly shows that eating fresh fruit can reduce the risk of cardiovascular disease, including ischaemic heart disease and stroke (particularly haemorrhagic stroke). And not only that, the more fruit you eat the more your CVD risk goes down. It does suggest that eating more fruit is beneficial compared to less or no fruit.”
The researchers also found that people who consumed fruit more often had significantly lower blood pressure (BP). Eating fruit daily was associated with 3.4/4.1 mmHg lower systolic/diastolic BP compared to those who never ate fruit. Dr Du said: “Our data shows that eating fresh fruit was associated with lower baseline BP. We also found that the beneficial effect of fruit on the risk of CVD was independent of its impact on baseline BP.”
In a separate analysis, the researchers examined the association of fruit consumption with total mortality and CV mortality in more than 61 000 patients from the China Kadoorie Biobank who had CVD or hypertension at baseline. They found that compared to those who never ate fruit, daily consumers of fruit cut their overall risk of death by 32%. They also reduced their risks of dying from IHD by 27% and from stroke by around 40%.
Professor Zhengming Chen, the principal investigator of the China Kadoorie Biobank, said: “Patients with CVD and hypertension should also be encouraged to consume more fresh fruit. Many western populations have experienced a rapid decrease in CVD mortality during the past several decades, especially stroke mortality since the early 1950s, for reasons that are not yet fully explained. Improved access to fresh fruit may well have contributed importantly to that decline.”
The researchers concluded: “Our results show the benefit of eating fruit in the healthy general population and in patients with CVD and hypertension. Fruit consumption is an effective way to cut CVD risk and should not only be regarded as ‘might be useful’. Policies are needed to promote the availability, affordability and acceptability of fresh fruit through educational and regulatory measures.”
Can action movies make you fat?
Snacking while watching action movies leads to overeating
Is television making us fat? An increasing amount of research shows an association between TV viewing and higher food consumption and a more sedentary lifestyle. Now, a new Cornell University study points out that not all TV is alike. Some TV programs might lead people to eat twice as much as other programs! “We find that if you’re watching an action movie while snacking your mouth will see more action too!” says Aner Tal, Ph.D. lead author on the new article just published in the Journal of the American Medical Association: Internal Medicine. “In other words, the more distracting the program is the more you will eat.”
In the study, conducted by researchers at the Cornell Food and Brand Lab, 94 undergraduates snacked on M&Ms, cookies, carrots and grapes while watching 20 minutes of television programming. A third of the participants watched a segment of the action movie The Island, a third watched a segment from the talk show, the Charlie Rose Show, and a third watched the same segment from The Island without sound.
“People who were watching The Island ate almost twice as many snacks – 98% more than those watching the talk show!” says co-author Brian Wansink, author of Slim by Design (forthcoming) and Professor and Director of the Cornell Food and Brand Lab. “Even those watching “The Island” without sound ate 36% more.” People watching the more distracting content also consumed more calories, with 354 calories consumed by those watching The Island (314 calories with no sound) compared to 215 calories consumed by those watching the Charlie Rose Show.
“More stimulating programs that are fast paced, include many camera cuts, really draw you in and distract you from what you are eating. They can make you eat more because you’re paying less attention to how much you are putting in your mouth,” explains Tal. Because of this, programs that engage viewers more might wind up being worse for their diets!
So what can you do to avoid overeating during your favorite chase scene? The researchers suggest pre-plating or pre-portioning your TV snacks instead of bringing out a whole bag of chips or box of cookies. Wansink notes that the best solution is to bring out the healthy munchable snacks, like carrots. “The good news,” says Wansink “is that action movie watchers also eat more healthy foods, if that’s what’s in front of them. Take advantage of this!”
Spinach extract decreases cravings, aids weight loss
A spinach extract containing green leaf membranes called thylakoids decreases hedonic hunger with up to 95% – and increases weight loss with 43%. This has been shown in a recently published long-term human study at Lund University in Sweden.
Hedonic hunger is another term for the cravings many people experience for unhealthy foods such as sweets or fast food, a common cause of obesity and unhealthy eating habits. The study shows that taking thylakoids reinforces the body’s production of satiety hormones and suppresses hedonic hunger, which leads to better appetite control, healthier eating habits and increased weight loss.
“Our analyses show that having a drink containing thylakoids before breakfast reduces cravings and keeps you feeling more satisfied all day”, says Charlotte Erlanson-Albertsson, Professor of Medicine and Physiological Chemistry at Lund University.
The study involved 38 overweight women and ran for three months. Every morning before breakfast the participants had a green drink. Half of the women were given 5 grams of spinach extract and the other half, the control group, were given a placebo. The participants did not know which group they belonged to – the only instructions they received were to eat a balanced diet including three meals a day and not to go on any other diet.
“In the study, the control group lost an average of 3.5 kg while the group that was given thylakoids lost 5 kg. The thylakoid group also found that it was easier to stick to three meals a day – and they did not experience any cravings”, said Charlotte Erlanson-Albertsson.
The key is the feeling of satiety and suppression of hedonic hunger, vs homeostatic hunger that deals with our basic energy needs. Modern processed food is broken down so quickly that the hormones in the intestines that send satiety signals to the brain and suppress cravings cannot keep up. The green leaf membranes slow down the digestion process, giving the intestinal hormones time to be released and communicate to the brain that we are satisfied.
“It is about making use of the time it takes to digest our food. There is nothing wrong with our digestive system, but it doesn’t work well with the modern ‘pre-chewed’ food. The thylakoids extend digestion, producing a feeling of satiety. This means that we are able to stick to the diet we are meant for without snacks and unnecessary foods like sweets, crisps and such”, says Charlotte Erlanson-Albertsson.
Estrogen increases cannabis sensitivity
Females more likely to see tolerance and addiction while males get the munchies
PULLMAN, Wash. – Smoking today’s concentrated pot might be risky business for women, according to new research from Washington State University. The study is the first to demonstrate sex differences in the development of tolerance to THC.
Psychology professor Rebecca Craft showed that, thanks to their estrogen levels, female rats are at least 30 percent more sensitive than males to the pain-relieving qualities of THC—the key active ingredient in cannabis. Females also develop tolerance to THC more quickly. These sensitivities could increase vulnerability to negative side effects like anxiety, paranoia and addiction.
The findings were recently published in the journal Drug and Alcohol Dependence.
The research was supported by a grant from the National Institute on Drug Abuse.
Craft said other researchers, like Margaret Haney at the Columbia University Medical Center, have shown that women are more susceptible to cannabis abuse and dependence than men. Haney has documented a cannabis withdrawal syndrome of irritability, sleep disruption and decreased food intake that Craft said tends to be more severe in women. Women also have a greater tendency to relapse when trying to stop using the drug.
Despite the known differences in how marijuana affects the sexes, Craft said most THC tolerance studies have been done on males.
With recent legalization of recreational marijuana in Washington and Colorado—and many more states allowing medicinal use—Craft said there is greater burden on researchers to understand the effects of cannabis and ferret out differences between males and females.
She said the “munchie effect” appears to be the only THC reaction where males show more sensitivity than females. Studies in California found that THC stimulated the appetites of male animals more than those of females.
The marijuana plant contains more than 60 compounds known as cannabinoids. THC, or tetrahydrocannabinol, is the psychoactive ingredient behind the characteristic mental high. Cannabidiol and cannabinol occur in smaller amounts but may be useful for medical purposes.
All three compounds are present in the most common species of marijuana, Cannabis sativa and C. indica, but in varying proportions.
Craft said most medical marijuana patients prefer a balance between the cannabinoids. But when it comes to recreational pot, selective breeding has resulted in THC concentrations double or triple those seen in the 1960s and 70s.
“Marijuana is very different than it was 40 years ago,” she said. “It’s much higher in THC and lower in cannabidiol, so a little bit goes a very long way.
“We’re more likely to see negative side effects today like anxiety, confusion, panic attacks, hallucinations or extreme paranoia,” she said. “And women are at higher risk.”
One of the few female studies
Most clinical drug trials have been conducted on men due to their more stable hormonal profile. Despite the recommendation of the National Institutes of Health in 1993 to include more women in studies or give good reasons not to, many researchers still avoid dealing with the hormone swings inherent in a woman’s biology.
But Craft has been studying drug sensitivities in females for years.
Working with rats in her laboratory, Craft said she and her team “routinely manipulate hormones and follow females across their cycles to see if their drug sensitivities change along with their hormones. And they do…very frequently.” Estrogen is the culprit.
“What we’re finding with THC is that you get a very clear spike in drug sensitivity right when the females are ovulating – right when their estrogen levels have peaked and are coming down,” she said.
In the current study, Craft and her team examined the pain relieving effects of THC in male and female rats. After 10 days of treatment, tolerance to THC was shown to be significantly greater in females than males.
Tolerance occurs when the rat “adapts” to THC so that larger doses are required to produce the same pain-relieving effects initially seen with the first dose.
Because Craft already knew that females were more sensitive to THC, she adjusted their doses to be 30 percent lower than doses for males. The females still developed more tolerance.
“This is the lowest dose anyone has ever used to induce tolerance,” she said.
The team also found that a low dose of THC did not disrupt the reproductive cycle in female rats, something that has been under debate and, Craft said, needs more study.
Hoping to gain greater insights into marijuana’s medical potential, Craft and her team are also studying the effects of cannabidiol, which can counter some of THC’s negative side effects.
The THC and cannabidiol studies will be extended to include chronic types of pain typically seen in people who request medical marijuana—such as those with debilitating back or joint pain, cancer, Crohn’s disease, multiple sclerosis, severe muscle spasms and more.
“These people have pain that lasts for months or years,” Craft said. “Tolerance develops differently and sometimes you get a lot less tolerance to a drug when people are in chronic pain.”
Craft uses a standard research formulation of delta-9-THC for her studies and is approved by the U.S. Drug Enforcement Administration to work with Schedule I drugs such as cannabis.
Intestinal barrier damage in multiple sclerosis
Researchers at Lund University have published new research findings on the role of the intestinal barrier in the autoimmune disease multiple sclerosis (MS).
Within medical science, it is not known for certain how MS develops or why the body’s immune system attacks cells in the central nervous system. Inflammation develops for an unknown reason, which hinders transport of neural impulses. This can produce various physical and mental symptoms, including a loss of sensation, motor difficulties, blurred vision, dizziness and tiredness.
The present study investigates whether the function of the intestines is also attacked in MS. The results, obtained from a disease model of MS in mice, shows inflammation and changes in the barrier function of the intestines early in the course of the disease. The study has been published in the scientific journal PLOS ONE.
“We know that the permeability of the intestines to harmful substances is raised in inflammatory bowel diseases such as Crohn’s disease and ulcerous colitis, as well as in some other autoimmune diseases such as type 1 diabetes. The condition is called ‘leaky gut syndrome’. Our studies indicate a leaky gut and increased inflammation in the intestinal mucous membrane and related lymphoid tissue before clinical symptoms of MS are discernible. It also appears that the inflammation increases as the disease develops”, said Shahram Lavasani, one of the authors of the study.
Dr Lavasani and his colleagues at Lund University have previously shown that probiotic bacteria could give a certain amount of protection against MS. They therefore wondered whether the intestinal barrier is affected and decided to investigate inflammatory cells and processes in the intestine. The hypothesis was tested in a research project in collaboration with Professor Björn Weström, doctoral student Mehrnaz Nouri and reader Anders Bredberg.
“To our surprise, we saw structural changes in the mucous membrane of the small intestine and an increase in inflammatory T-cells, known as Th1 and Th17. At the same time, we saw a reduction in immunosuppressive cells, known as regulatory T-cells. These changes are often linked to inflammatory bowel diseases, and biologically active molecules produced by Th1 and Th17 are believed to be behind this damage to the intestines.”
Neuroinflammatory processes in MS are believed to lead to damage and leakage in the blood-brain barrier that protects the central nervous system and regulates the transport of cells. The researchers have now observed similar damage in the intestinal barrier, especially to the ‘tight junctions’ that bind the cells together in the mucous membrane of the intestine, and have demonstrated that these are connected to disease-specific T-cells.
“In most cases, we don’t know what triggers autoimmune diseases, but we know that pathogenic cells frequent and disrupt the intestines. A leaky gut enables harmful bacteria and toxic substances in the body to enter the intestine, which creates even more inflammation. Our findings provide support for the idea that a damaged intestinal barrier can prevent the body ending an autoimmune reaction in the normal manner, leading to a chronic disease such as MS”, said Dr Lavasani.
Shahram Lavasani and his colleagues believe that future drugs to treat this type of disease should perhaps not only focus on the central nervous system, but also on the intestines by repairing and restoring the intestinal barrier.
“In the long run, we hope that our findings will lead to better understanding of what actually happens in the development of MS. Looking even further to the future, we hope for the development of a better treatment that aims at the intestinal barrier as a new therapeutic target.”
The research group is now studying other inflammatory parameters in the gut that could affect the development of MS. Their aim is to draw up treatment methods that can heal the mucous membrane in the intestine in the hope of preventing the development of the disease. Some of this work forms part of Mehrnaz Nouri’s thesis, which will be defended later in the year.
Study: Oxidized LDL might actually be ‘good guy’
LEXINGTON, Ky (Sept. 4, 2014) — A team of investigators at the University of Kentucky has made a thought-provoking discovery about a type of cholesterol previously believed to be a “bad guy” in the development of heart disease and other conditions.
Jason Meyer, a University of Kentucky MD-PhD candidate, worked with Deneys van der Westhuyzen, Ph.D., a Professor in the Departments of Internal Medicine and Molecular and Cellular Biochemistry, to study the role oxidized LDL plays in the development of plaque inside artery walls.
According to Meyer, the medical research community has traditionally believed that oxidized LDL plays a pivotal role in that process.
“Oxidized LDL moves rapidly into arterial walls and engorges them with cholesterol,” explains Meyer. “Cholesterol ultimately converts into plaque, blocking the arteries or, in a worst case scenario, rupturing and sending clots into the bloodstream, causing heart attacks and/or strokes.”
However, more recent studies in animals and humans have brought that assumption into question, and the oxidized LDL theory is currently the subject of lively debate.
Though in its very early stages, our research will add considerably to that controversy,” Meyer says, “because it seems to indicate that oxidized LDL might in fact be a ‘good guy’ in the process.”
The team’s findings come from a project studying a pathway of cholesterol transport called “selective lipid uptake.”
“Based on our analysis, we were surprised to find that, instead of increasing the amount of cholesterol uptake and accumulation in the macrophage foam cells, mildly oxidized LDL almost completely prevents increases in cholesterol,” Dr. van der Westhuyzen said.
Meyer says the implications of the study are potentially profound.
“If it is demonstrated that oxidized LDL actually has a preventive effect on the accumulation of cholesterol in arterial walls, it may be possible to create a medicine from oxidized LDL to help prevent or treat this killer disease,” Meyer said. “There is still much work to do because this project is very early in development and has not been tested in animals, but the results we have so far are very promising.”
Meyer and van der Westhuyzen’s findings were published in the August issue of the Journal of Lipid Research.
Flour identified as the main cause of occupational asthma in France
Munich, Germany: Flour has been identified as the main cause of occupational asthma in France, closely followed by cleaning products.
A new study, which was presented at the European Respiratory Society’s International Congress today (07 September 2014), analysed all cases of occupational asthma in France. The research, which is the largest of its kind to be undertaken in France, aimed to understand who was most affected by the condition and what the main causes were.
Data were collected over a 3-year period from a network of respiratory doctors specialised in occupational diseases. 330 cases were analysed.
Researchers estimated the incidence rate based on the figures they collected and the results of the analysis showed that;
- Flour was identified as the main cause (seen in 20% of cases), closely followed by ammonium compounds often found in cleaning products (seen in 15% of cases)
- Women were more likely to be diagnosed with occupational asthma (43 per million compared with 29 per million seen in men)
- Incidence rates were higher among skilled and unskilled workers (116 per million) when compared with farmers (97 per million)
- The highest incidence rate was seen in people working in the manufacture of food products and beverages (279 per million) compared with those working in agriculture (160 per million)
Professor Frederic De Blay, lead author from the University Hospital Strasborg, said: “This study has given us a detailed understanding of the occupational asthma cases in France. It helps to show us where people are being exposed to harmful agents and who is most likely to be affected. These findings are important as they can help with future prevention methods to make sure people who are at risk of occupational asthma are protected from it.”
Fish oil may help curb seizure frequency in epilepsy
Low doses might be helpful in epilepsy that no longer responds to drug treatment
But high doses were no better than dummy (placebo treatment), the findings indicated.
The omega-3 fatty acids found in fish oil are able to cross over from the bloodstream into heart cells where they work to stabilise heart rhythm and protect against heart attacks.
This is particularly important for people with epilepsy because they have a significantly higher risk of having a heart attack than those without the condition.
And experimental research indicates that omega 3 fatty acids can also cross over into the central nervous system, where they reduce the excitability of brain cells which trigger seizures.
But previous research looking at the impact of high dose fish oil on seizure frequency in people whose epilepsy no longer responded to treatment, found that it didn’t affect seizure frequency.
The researchers in the current study wanted to know what difference, if any, low dose fish oil made to seizure frequency and/or cardiovascular health.
Twenty four people, whose epilepsy was no longer responsive to drugs were therefore given three separate treatments, each lasting 10 weeks, and separated by a period of 6 weeks.
These comprised: 3 capsules of fish oil daily (low dose) equivalent to 1080 mg omega-3 fatty acids every day, plus 3 capsules of corn oil (placebo); 6 capsules of fish oil daily, equivalent to 2160 mg every day; and 3 capsules of corn oil twice a day.
The average number of seizures among those taking low dose fish oil was around 12 a month. This compares with just over 17 for the high dose, and just over 18 for the placebo, equivalent to a fall of a third (33.6%) in the number of seizures while on the low dose.
Two people on the low dose were completely seizure free during the 10 week trial. No one taking the high dose fish oil or the placebo was seizure free.
Low dose fish oil was also associated with a modest fall in blood pressure of 1.95 mm Hg over the 10 week period, unlike high dose fish oil which was associated with an average increase of 1.84 mm Hg.
But fish oil was not associated with any changes in heart rate or blood fat levels, or severity of seizures.
The researchers caution that a much larger study is needed to confirm or refute these findings before any firm conclusions can be drawn, and recommendations made.
But they write: “Low dose fish oil is a safe and low cost intervention that may reduce seizures and improve cardiovascular health in people with epilepsy.”
Breast milk may be protective against devastating intestinal disorder
Growth factor found in breast milk may be protective against devastating intestinal disorder of newborn infants
Premature infants are at increased risk for a potentially lethal gastrointestinal disease called necrotizing enterocolitis, or NEC. Studies conducted by researchers at Children’s Hospital Los Angeles demonstrate that a protein called neuregulin-4 (NRG4)—present in breast milk, but absent from formula—may be protective against the intestinal destruction caused in NEC. Their results will be published online on September 9 in advance of the print edition of the American Journal of Pathology.
Thirty percent of babies with NEC die from their disease, and even survivors can face lifelong consequences that may include removal of part of their intestine and dependence upon intravenous nutrition. Formula feeding is a known risk factor for the disease.
“Our research suggests that without the NRG4 protein found in breast milk, a normal protection mechanism for the immature gut may be missing,” said Mark R. Frey, PhD, the study’s principal investigator at The Saban Research Institute of Children’s Hospital Los Angeles. “If a baby on formula encounters an NEC trigger such as intestinal infection or injury, he or she may be at increased risk for a life-threatening condition.”
The investigators conducted a series of studies using rodent models, as well as in vitro analysis and examination of human breast milk and infant intestinal tissue. Formula-fed rats developed a condition similar to NEC, but those receiving formula plus the NRG4 were protected against intestinal damage, as were cultured intestinal cells challenged with bacteria related to strains that may induce NEC in humans. These experiments suggest that NRG4 binds specifically with a receptor found in the intestine, ErbB4, to block inflammatory intestinal damage. In addition, NRG4 was present in human breast milk samples but not formula.
Human NEC is characterized by a loss of specialized intestinal cells, called Paneth cells. Located throughout the small intestine, these cells protect the organ from microbial damage. The Paneth cells also sustain intestinal stem cells that are required for ongoing renewal of the intestinal lining. In a mouse model of NEC, the investigators demonstrated that NRG4 prevented loss of Paneth cells.
“We’re finding a protective protein in breast milk, with its receptor in the intestine,” says Frey, who is also an assistant professor of Pediatrics and Biochemistry & Molecular Biology at the Keck School of Medicine of the University of Southern California. “Given that NEC is a significant clinical problem without an effective treatment, we plan to evaluate NRG4 for its therapeutic potential in this disease.”
New study: Emerging research indicates mangos may lower blood sugar in obese adults
ORLANDO, FL – SEPTEMBER 9, 2014 – Research published in the journal Nutrition and Metabolic Insights found that regular consumption of mango by obese adults may lower blood sugar levels and does not negatively impact body weight. These are important findings considering that approximately 34 percent of U.S. adults have been classified as obese and given the health concerns related to obesity, such as type 2 diabetes (T2DM) and metabolic syndrome.
“We are excited about these promising findings for mangos, which contain many bioactive compounds, including mangiferin, an antioxidant that may contribute to the beneficial effects of mango on blood glucose. In addition, mangos contain fiber, which can help lower glucose absorption into the blood stream,” said Edralin Lucas, Ph.D., associate professor of nutritional sciences at Oklahoma State University, College of Human Sciences and lead study author. “Our results indicate that daily consumption of 10 grams of freeze-dried mango, which is equivalent to about one-half of a fresh mango (about 100 grams), may help lower blood sugar in obese individuals.”
This pilot study was designed to investigate the effects of mango consumption on anthropometric measurements, biochemical parameters, and body composition in obese adults. Participants completing the 12-week study included 20 adults (11 males and 9 females) ages 20 to 50 years old with a Body Mass Index (BMI) of 30 to 45 kg/m2. The study subjects were asked to maintain their usual diet, exercise habits, and regimen of regularly prescribed medications.
Each day during the study period, participants consumed 10 grams of freeze-dried mango, and dietary intake was monitored via 3-day food records assessed at baseline and after 6- and 12- weeks of mango supplementation. Anthropometric measurements (height, weight, and circumference of waist and hip) were measured at baseline and after 6- and 12- weeks of mango supplementation. Body composition and blood analyses of fasting blood triglyceride, HDL-cholesterol, glucose, hemoglobin A1c, and plasma insulin concentration were evaluated at baseline and at the end of 12 weeks of mango supplementation.
The researchers found that after 12 weeks, participants had reduced blood glucose (-4.41 mg/dL, P<0.001), and this glucose lowering effect was seen in both males (-4.5 mg/dL, P=0.018) and females (-3.6 mg/dL, P=0.003). No changes were observed in overall body weight, hip or waist circumference, waist to hip ratio, percent fat mass, and lean mass. However, hip circumference was significantly lower in males (-3.3 cm, P=0.048) but not females. BMI tended to be higher in females (+0.9 kg/m2, P=0.062) but not males after mango supplementation, although these results were not statistically significant. Overall and by gender, there were no significant changes in triglycerides, HDL-cholesterol, or blood pressure. The blood sugar findings of this study are in agreement with Lucas’ previous animal research, which was published in the British Journal of Nutrition.
“We believe this research suggests that mangos may give obese individuals a dietary option in helping them maintain or lower their blood sugar. However, the precise component and mechanism has yet to be found and further clinical trials are necessary, particularly in those that have problems with sugar control, such as diabetics, are necessary,” said Lucas.
Results from this present study could have been influenced by a number of factors including the small sample size, lack of a control group, duration of mango supplementation, inaccurate self-reporting of dietary intake and physical activity level by study subjects, or from lack of compliance with daily mango supplementation as part of the study protocol. Additional human studies with larger sample sizes and of longer duration of mango supplementation should be conducted.
A nutrient rich fruit, mangos contain over 20 different vitamins and minerals, supporting optimal function of processes throughout the body. Mangos are an excellent source of the antioxidant vitamins C and A as well as folate. They are also a good source of fiber, copper, and vitamin B6.
Hold the Mayo
Researchers at UCSB and the University of Pittsburgh use breast milk to show a correlation between dietary fats and academic success
By Andrea Estrada
Tuesday, September 9, 2014 – 22:45
Santa Barbara, CA
This graph shows the relationship between breast milk fats and test
performance. Countries in which diets contain less of the good (omega-3) fat and more bad (omega-6) fat are toward the left. Those with better test score are toward the top. Breast milk in the USA is among the worst in terms of its fat balance, but children perform somewhat better than expected based on this nutritional data alone.
You are what you eat, the saying goes, and now a study conducted by researchers at UC Santa Barbara and the University of Pittsburgh suggests that the oft-repeated adage applies not just to physical health but to brain power as well.
In a paper published in the early online edition of the journal Prostaglandins, Leukotrienes and Essential Fatty Acids, the researchers compared the fatty acid profiles of breast milk from women in over two dozen countries with how well children from those same countries performed on academic tests.
Their findings show that the amount of omega-3 docosahexaenoic acid (DHA) in a mother’s milk — fats found primarily in certain fish, nuts and seeds — is the strongest predictor of test performance. It outweighs national income and the number of dollars spent per pupil in schools.
DHA alone accounted for about 20 percent of the differences in test scores among countries, the researchers found.
On the other hand, the amount of omega-6 fat in mother’s milk — fats that come from vegetable oils such as corn and soybean — predict lower test scores. When the amount of DHA and linoleic acid (LA) — the most common omega-6 fat — were considered together, they explained nearly half of the differences in test scores. In countries where mother’s diets contain more omega-6, the beneficial effects of DHA seem to be reduced.
“Human intelligence has a physical basis in the huge size of our brains — some seven times larger than would be expected for a mammal with our body size,” said Steven Gaulin, UCSB professor of anthropology and co-author of the paper. “Since there is never a free lunch, those big brains need lots of extra building materials — most importantly, they need omega-3 fatty acids, especially DHA. Omega-6 fats, however, undermine the effects of DHA and seem to be bad for brains.”
Both kinds of omega fat must be obtained through diet. But because diets vary from place to place, for their study Gaulin and his co-author, William D. Lassek, M.D., a professor at the University of Pittsburgh’s Graduate School of Public Health and a retired assistant surgeon general, estimated the DHA and LA content — the good fat and the bad fat — in diets in 50 countries by examining published studies of the fatty acid profiles of women’s breast milk.
The profiles are a useful measure for two reasons, according to Gaulin. First, because various kinds of fats interfere with one another in the body, breast milk DHA shows how much of this brain-essential fat survives competition with omega-6. Second, children receive their brain-building fats from their mothers. Breast milk profiles indicate the amount of DHA children in each region receive in the womb, through breastfeeding, and from the local diet available to their mothers and to them after they are weaned.
The academic test results came from the Programme for International Student Assessment (PISA), which administers standardized tests in 58 nations. Gaulin and Lassek averaged the three PISA tests — math, science and reading ability — as their measure of cognitive performance. There were 28 countries for which the researchers found information about both breast milk and test scores.
“Looking at those 28 countries, the DHA content of breast milk was the single best predictor of math test performance,” Gaulin said. The second best indicator was the amount of omega-6, and its effect is opposite. “Considering the benefits of omega-3 and the detriment of omega-6, we can get pretty darn close to explaining half the difference in scores between countries,” he added. When DHA and LA are considered together, he added, they are twice as effective at predicting test scores as either is alone, Gaulin said.
Gaulin and Lassek considered two economic factors as well: per capita gross domestic product (a measure of average wealth in each nation) and per student expenditures on education. “Each of these factors helps explain some of the differences between nations in test scores, but the fatty acid profile of the average mother’s milk in a given country is a better predictor of the average cognitive performance in that country than is either of the conventional socioeconomic measures people use,” said Gaulin.
From their analysis, the researchers conclude that both economic wellbeing and diet make a difference in cognitive test performance, and children are best off when they have both factors in their favor. “But if you had to choose one, you should choose the better diet rather than the better economy,” Gaulin said.
The current research follows a study published in 2008 that showed that the children of women who had larger amounts of gluteofemoral fat “depots” performed better on academic tests than those of mothers with less. “At that time we weren’t trying to identify the dietary cause,” explained Gaulin. “We found that this depot that has been evolutionarily elaborated in women is important to building a good brain. We were content at that time to show that as a way of understanding why the female body is as evolutionarily distinctive as it is.”
Now the researchers are looking at diet as the key to brain-building fat, since mothers need to acquire these fats in the first place.
Their results are particularly interesting in 21st-century North America, Gaulin noted, because our current agribusiness-based diets provide very low levels of DHA — among the lowest in the world. Thanks to two heavily government-subsidized crops — corn and soybeans — the average U.S. diet is heavy in the bad omega-6 fatty acids and far too light on the good omega-3s, Gaulin said.
“Back in the 1960s, in the middle of the cardiovascular disease epidemic, people got the idea that saturated fats were bad and polyunsaturated fats were good,” he explained. “That’s one reason margarine became so popular. But the polyunsaturated fats that were increased were the ones with omega-6, not omega-3. So our message is that not only is it advisable to increase omega 3 intake, it’s highly advisable to decrease omega-6 — the very fats that in the 1960s and ’70s we were told we should be eating more of.”
Gaulin added that mayonnaise is, in general, the most omega-6-laden food in the average person’s refrigerator. “If you have too much of one — omega-6 — and too little of the other — omega 3 — you’re going to end up paying a price cognitively,” he said.
The issue is a huge concern for women, Gaulin noted, because “that’s where kids’ brains come from. But it’s important for men as well because they have to take care of the brains their moms gave them.
“Just like a racecar burns up some of its motor oil with every lap, your brain burns up omega-3 and you need to replenish it every day,” he said.
Gut microbes determine how well the flu vaccine works
Annual flu epidemics cause millions of cases of severe illness and up to half a million deaths every year around the world, despite widespread vaccination programs. A study published by Cell Press on September 11th in Immunity reveals that gut microbes play an important role in stimulating protective immune responses to the seasonal flu vaccine in mice, suggesting that differences in the composition of gut microbes in different populations may impact vaccine immunity. The study paves the way for global public health strategies to improve the effectiveness of the flu vaccine.
“Our findings raise the possibility that antibiotic treatment prior to or during vaccination may impact immunity,” says senior study author Bali Pulendran of the Emory Vaccine Research Center. “Another potential implication of our study is that we may be able to manipulate gut microbes in order to improve immune responses to the vaccine.”
Vaccines are less effective in many parts of developing countries compared to industrialized areas, and a significant proportion of vaccinated individuals, especially the young and elderly, remain susceptible to infection. The underlying reasons for the lack of complete protection have not been clear, in part because relatively little is known about how vaccines elicit host immune responses.
In a previous study, Pulendran and his team found that the antibody response in healthy human adults vaccinated with the seasonal flu vaccine, known as trivalent inactivated influenza vaccine (TIV), depended on expression of a gene called Toll-like receptor 5 (TLR5). Because this gene encodes a cell-surface receptor that detects bacterial flagellin—a protein that makes up the whip-like appendage that helps bacteria move—the researchers suspected that gut microbes may influence immunity to flu vaccination.
Pulendran and his collaborators tested this possibility in the new study. Upon vaccination with TIV, mice that were genetically manipulated to lack TLR5 showed significantly reduced antibody responses compared with normal mice. Moreover, mice that were either raised in a germ-free environment or treated with antibiotics showed lower vaccine-induced antibody levels compared with germ-exposed mice. TLR5-deficient mice also showed reduced antibody responses to the polio vaccine, which is composed of specific viral molecules rather than an active virus, similar to TIV.
Taken together, the findings suggest that the effectiveness of inactivated, subunit vaccines in eliciting protective immune responses strongly depends on gut microbes. “In the future, it will be important to determine the impact of antibiotic treatment on immunity to vaccination in humans and to study whether differences in the composition of gut microbes in different populations can impact vaccine immunity,” Pulendran says.
Not enough vitamin B1 can cause brain damage
Toxins and other metabolic disorders also can cause encephalopathy
MAYWOOD, Ill – (Sept. 11, 2014) A deficiency of a single vitamin, B1 (thiamine), can cause a potentially fatal brain disorder called Wernicke encephalopathy.
Symptoms can include confusion, hallucinations, coma, loss of muscle coordination and vision problems such as double vision and involuntary eye movements. Untreated, the condition can lead to irreversible brain damage and death, according to neurologists at Loyola University Medical Center.
In the developed world, Wernicke encephalopathy typically occurs in people who have disorders such as alcoholism and anorexia that lead to malnourishment.
Wernicke encephalopathy is an example of the wide range of brain diseases, called encephalopathies, that are caused by metabolic disorders and toxic substances, according to a report by Loyola neurologists Matthew McCoyd, MD, Sean Ruland, DO and Jose Biller, MD in the journal Scientific American Medicine.
Acute encephalopathy has a rapid onset of between hours and days. It is commonly due to toxic and metabolic factors.
“Toxic and metabolic encephalopathies may range in severity from the acute confusional state to frank coma,” McCoyd, Ruland and Biller write. “As permanent injury may occur, an organized approach is needed to make an accurate and rapid diagnosis.”
The hallmark of toxic and metabolic encephalopathies is altered sensorium. This can range from mild attention impairment, such as difficulty spelling a word backwards, to coma.
Toxic encephalopathy can be caused by illegal drugs, environmental toxins and reactions to prescription drugs.
Thiamine deficiency is among the nutritional deficiencies that can cause brain diseases such as Wernicke encephalopathy. The condition likely is underdiagnosed. Although clinical studies find a rate of 0.13 percent or less, autopsy studies show a prevalence as high as 2.8 percent.
“Particularly in those who suffer from alcoholism or AIDS, the diagnosis is missed on clinical examination in 75 to 80 percent of cases,” the Loyola neurologists write.
Untreated, Wernicke encephalopathy can lead to Korsakoff syndrome (KS), characterized by profound memory loss and inability to form memories – patients often can’t remember events within the past 30 minutes. Other KS symptoms can include apathy, anxiety and confabulation (fabricating imaginary experiences to compensate for memory loss).
About 80 percent of Wernicke encephalopathy patients develop KS, and once this occurs, only about 20 percent of patients recover.
Wernicke encephalopathy is a medical emergency that requires immediate thiamine treatment, either by injection or IV. “In the absence of treatment, deficiency can lead to irreversible brain damage and death with an estimated mortality of 20 percent,” the Loyola neurologists write.