A daily dose of two grams of cinnamon for 12 weeks may improve blood pressure measures and blood sugar levels in people with type-2 diabetes, says new research from Imperial College London.
According to findings of the randomized, placebo-controlled, double-blind clinical trial, the spice may be considered as interesting supplement to the conventional diabetes medications.
“The two gram dose of cinnamon administered in our study was safe and well tolerated over the 12 weeks of treatment,” wrote Dr Rajadurai Akilen and his co-workers in Diabetic Medicine.
“The sustainability and durability of the effect of cinnamon has not been tested, nor has its long-term tolerability and safety, both of which will need to be determined. However, the short-term effects of the use of cinnamon for patients with Type 2 diabetes look promising.”
Exploding statistics
The study adds to a growing body of research reporting that active compounds in cinnamon may improve parameters associated with diabetes.
With the number of people are affected by diabetes in the EU 25 projected to increase to 26 million by 2030, up from about 19 million currently – or 4 per cent of the total population –approaches to reduce the risk of diabetes are becoming increasing attractive.
The statistics are even more startling in the US, where almost 24 million people live with diabetes, equal to 8 per cent of the population. The total costs are thought to be as much as $174 billion, with $116 billion being direct costs from medication, according to 2005-2007 American Diabetes Association figures.
At the end of the study the results indicated that the cinnamon supplement was associated with a mean decrease in systolic and diastolic blood pressure of 3.4 and 5.0 mmHg, respectively. No significant reductions were recorded in the placebo group.
In terms of blood sugar, the researchers noted a reduction in levels of glycated hemoglobin (used to measure blood sugar levels) over 12 weeks from 8.22 to 7.86 percent in the cinnamon group, compared with an increase in the placebo group from 8.55 to 8.68 percent over 12 weeks.
“This is the first clinical trial in the United Kingdom in a multiethnic population that has confirmed beneficial effects of 2 g cinnamon on [glycated hemoglobin] and blood pressure in Type-2 diabetes patients,” wrote the researchers.
Cinnamon and diabetes
Despite numerous studies championing the role of cinnamon for diabetes management, a recent meta-analysis questioned the potential benefits of cinnamon for type-2 diabetes. The analysis considered only five randomized placebo-controlled trials involving 282 subjects, and found no significant benefits of cinnamon supplement on glycated hemoglobin (A1C), fasting blood glucose (FBG), or other lipid parameters (Diabetes Care, 2008, Vol. 31, pp. 41-43).
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3 December 2010
Belly fat may weaken bones
One of the few possible advantages of carrying extra weight is being shot down
In the past, doctors had suggested that excess body fat, which is associated with heart disease, diabetes, and many other bodily harms, may protect against the bone disease osteoporosis.
But now, a study finds that even this may be misleading. In fact, deep belly fat may contribute to osteoporosis, say scientists whose research will be presented at the Radiological Society of North America.
That's because the fat cells most likely produce substances, not yet understood, that lead to bone disease in addition to heart disease and diabetes, said Dr. Miriam Bredella of Harvard Medical School and Massachusetts General Hospital, where the study was conducted.
Bredella and colleagues looked at 50 premenopausal women and examined their fat using computerized tomography (CT), which can distinguish between compartments of fat. Bredella said the human body has two categories of fat: superficial fat, which lies under the skin, and visceral fat, which surrounds organs. The first type of fat has been shown to have benefits against diabetes and heart disease when distributed around the hips.
It's the second kind of fat, the deep belly fat, that is bad for bones, she said. The study found that this fat was associated with lower bone mineral density, a measure of bone strength.
Most other studies on fat and osteoporosis have looked at weight or body mass index (BMI), which do not reflect this distribution of fat, she said.
And there's no way to know where the fat goes when you gain weight, as it's largely determined by genetics, she said.
The researchers also used a new technique to look at bone marrow fat, or fat within bones, which also appears to make the bones weaker. Women with deep tummy fat also had more fat within their bones, Bredella said.
On the other hand, women with anorexia have also been known to be at increased risk of osteoporosis. The bottom line is that you should strive for a normal weight, because the extremes of too much or too little fat are both bad for bones, Bredella said.
The research is being presented for the first time at the conference, and has not yet appeared in a peer-reviewed journal. Further work should be done to confirm the results.
A future study will look at the relationship between deep belly fat and osteoporosis among men, Bredella said.
In the past, doctors had suggested that excess body fat, which is associated with heart disease, diabetes, and many other bodily harms, may protect against the bone disease osteoporosis.
But now, a study finds that even this may be misleading. In fact, deep belly fat may contribute to osteoporosis, say scientists whose research will be presented at the Radiological Society of North America.
That's because the fat cells most likely produce substances, not yet understood, that lead to bone disease in addition to heart disease and diabetes, said Dr. Miriam Bredella of Harvard Medical School and Massachusetts General Hospital, where the study was conducted.
Bredella and colleagues looked at 50 premenopausal women and examined their fat using computerized tomography (CT), which can distinguish between compartments of fat. Bredella said the human body has two categories of fat: superficial fat, which lies under the skin, and visceral fat, which surrounds organs. The first type of fat has been shown to have benefits against diabetes and heart disease when distributed around the hips.
It's the second kind of fat, the deep belly fat, that is bad for bones, she said. The study found that this fat was associated with lower bone mineral density, a measure of bone strength.
Most other studies on fat and osteoporosis have looked at weight or body mass index (BMI), which do not reflect this distribution of fat, she said.
And there's no way to know where the fat goes when you gain weight, as it's largely determined by genetics, she said.
The researchers also used a new technique to look at bone marrow fat, or fat within bones, which also appears to make the bones weaker. Women with deep tummy fat also had more fat within their bones, Bredella said.
On the other hand, women with anorexia have also been known to be at increased risk of osteoporosis. The bottom line is that you should strive for a normal weight, because the extremes of too much or too little fat are both bad for bones, Bredella said.
The research is being presented for the first time at the conference, and has not yet appeared in a peer-reviewed journal. Further work should be done to confirm the results.
A future study will look at the relationship between deep belly fat and osteoporosis among men, Bredella said.
For Health Benefits, Try Tai Chi
The gentle, 2,000-year-old Chinese practice of tai chi is often described as "meditation in motion." But the Harvard Women's Health Watch newsletter suggests a more apt description is "medication in motion."
Tai chi, the most famous branch of Qigong, or exercises that harness the qi (life energy, pronounced "chee"), has been linked to health benefits for virtually everyone from children to seniors. Researchers aren't sure exactly how, but studies show that tai chi improves the quality of life for breast cancer patients and Parkinson's sufferers. Its combination of martial arts movements and deep breathing can be adapted even for people in wheelchairs. And it has shown promise in treating sleep problems and high blood pressure.
Flexibility and strength. Tai chi is credited with so many pluses, physiological and psychological, that Chenchen Wang, an associate professor of medicine at Tufts University, set out earlier this year to analyze 40 studies on it in English and Chinese journals. Wang found that tai chi did indeed promote balance, flexibility, cardiovascular fitness, and strength. In a study comparing it with brisk walking and resistance training, a tai chi group improved more than 30 percent in lower-body strength and 25 percent in arm strength, nearly as much as a weight-training group and more than the walkers.
[For Better Balance, Pilates and Tai Chi Beat Yoga]
"Benefit was also found for pain, stress, and anxiety in healthy subjects," adds Wang, who was influenced by her mother, a Chinese doctor, to study an integration of complementary and alternative medicine with Western medicine.
In a 2008 analysis, Harvard Medical School's Gloria Yeh, an internist and assistant professor, reviewed 26 studies in English and Chinese and reported that in 85 percent of trials, tai chi lowered blood pressure. Other studies have shown it to reduce blood levels of B-type natriuretic peptide, a precursor of heart failure, and to maintain bone density in postmenopausal women. The nonprofit Arthritis Foundation offers its own 12-movement tai chi sequence.
Wang says more study is needed. Still, says New York Times personal health writer Jane Brody: "After reviewing existing scientific evidence for its potential health benefits, I've concluded that the proper question to ask yourself may not be why you should practice tai chi, but why not."
Lesson One: Find a teacher. "Learning from a book or video just does not work," says Greg Woodson, vice president of the international T'ai Chi Foundation and a teacher for 35 years. Students need real feedback from a teacher who can make sure exercises are done correctly "so the practice does not cause the type of injury it's designed to alleviate," he says. One example: Weight-bearing feet need to be flat on the floor to avoid knee stress, "an extremely subtle point that an experienced teacher will see." Woodson suggests that if a teacher has less than 10 years of experience, you should make sure he or she has the backing of a school or a more experienced teacher.
[Tai Chi May Help Ward Off Knee Pain in Seniors]
How much tai chi is enough? "Data suggest the minimum amount for effective results" is once- or twice-weekly sessions for eight to 12 weeks, says Wang. No pain, big gains.
Tai chi, the most famous branch of Qigong, or exercises that harness the qi (life energy, pronounced "chee"), has been linked to health benefits for virtually everyone from children to seniors. Researchers aren't sure exactly how, but studies show that tai chi improves the quality of life for breast cancer patients and Parkinson's sufferers. Its combination of martial arts movements and deep breathing can be adapted even for people in wheelchairs. And it has shown promise in treating sleep problems and high blood pressure.
Flexibility and strength. Tai chi is credited with so many pluses, physiological and psychological, that Chenchen Wang, an associate professor of medicine at Tufts University, set out earlier this year to analyze 40 studies on it in English and Chinese journals. Wang found that tai chi did indeed promote balance, flexibility, cardiovascular fitness, and strength. In a study comparing it with brisk walking and resistance training, a tai chi group improved more than 30 percent in lower-body strength and 25 percent in arm strength, nearly as much as a weight-training group and more than the walkers.
[For Better Balance, Pilates and Tai Chi Beat Yoga]
"Benefit was also found for pain, stress, and anxiety in healthy subjects," adds Wang, who was influenced by her mother, a Chinese doctor, to study an integration of complementary and alternative medicine with Western medicine.
In a 2008 analysis, Harvard Medical School's Gloria Yeh, an internist and assistant professor, reviewed 26 studies in English and Chinese and reported that in 85 percent of trials, tai chi lowered blood pressure. Other studies have shown it to reduce blood levels of B-type natriuretic peptide, a precursor of heart failure, and to maintain bone density in postmenopausal women. The nonprofit Arthritis Foundation offers its own 12-movement tai chi sequence.
Wang says more study is needed. Still, says New York Times personal health writer Jane Brody: "After reviewing existing scientific evidence for its potential health benefits, I've concluded that the proper question to ask yourself may not be why you should practice tai chi, but why not."
Lesson One: Find a teacher. "Learning from a book or video just does not work," says Greg Woodson, vice president of the international T'ai Chi Foundation and a teacher for 35 years. Students need real feedback from a teacher who can make sure exercises are done correctly "so the practice does not cause the type of injury it's designed to alleviate," he says. One example: Weight-bearing feet need to be flat on the floor to avoid knee stress, "an extremely subtle point that an experienced teacher will see." Woodson suggests that if a teacher has less than 10 years of experience, you should make sure he or she has the backing of a school or a more experienced teacher.
[Tai Chi May Help Ward Off Knee Pain in Seniors]
How much tai chi is enough? "Data suggest the minimum amount for effective results" is once- or twice-weekly sessions for eight to 12 weeks, says Wang. No pain, big gains.
Today, the Food and Nutrition Board has Failed Millions
After 13 years of silence, the quasi governmental agency, the Institute of Medicine's (IOM) Food and Nutrition Board (FNB), yesterday recommended that a three - pound premature infant can take virtually the same amount of vitamin D as a 300 pound pregnant woman. While that 400 IU/day dose is close to adequate for infants, 600 IU/day in pregnant women will do nothing to help the three childhood epidemics most closely associated with gestational and early childhood vitamin D deficiencies: asthma, auto-immune disorders, and, as recently reported in the largest pediatric journal in the world, autism (1). Professor Bruce Hollis of the Medical University of South Carolina has shown pregnant and lactating women need at least 5,000 IU/day, not 600.
The FNB also reported that vitamin D toxicity might occur at an intake of 10,000 IU/day (250 micrograms), although they could produce no reproducible evidence that 10,000 IU/day has ever caused toxicity in humans and only one poorly conducted study indicating 20,000 IU/day may cause mild elevations in serum calcium but not clinical toxicity.
Viewed with different measure, this FNB report recommends that an infant should take 10 micrograms/day (400 IU) and the pregnant women 15 micrograms/day (600 IU). As a single 30 minutes dose of summer sunshine gives adults more than 10,000 IU (250 micrograms), the FNB is apparently also warning that natural vitamin D input – as occurred from the sun before the widespread use of sunscreen – is dangerous. That is, the FNB is implying that God does not know what she is doing.
Disturbingly, this FNB committee focused on bone health, just like they did 14 years ago. They ignored the thousands of studies from the last ten years that showed higher doses of vitamin D helps: heart health, brain health, breast health, prostate health, pancreatic health, muscle health, nerve health, eye health, immune health, colon health, liver health, mood health, skin health, and especially fetal health. Tens of millions of pregnant women and their breast-feeding infants are severely vitamin D deficient, resulting in a great increase in the medieval disease, rickets. The FNB report seems to reason that if so many pregnant women have low vitamin D blood levels then it must be OK because such low levels are so common. However, such circular logic simply represents the cave man existence of most modern day pregnant women.
Hence, if you want to optimize your vitamin D levels – not just optimize the bone effect – supplementing is crucial. But it is almost impossible to significantly raise your vitamin D levels when supplementing at only 600 IU/day (15 micrograms). Pregnant women taking 400 IU/day have the same blood levels as pregnant women not taking vitamin D; that is, 400 IU is a meaninglessly small dose for pregnant women. Even taking 2,000 IU/day of vitamin D will only increase the vitamin D levels of most pregnant women by about 10 points, depending mainly on their weight. Professor Bruce Hollis has shown that 2,000 IU/day does not raise vitamin D to healthy or natural levels in either pregnant or lactating women. Therefore supplementing with higher amounts -- like 5000 IU/day -- is crucial for those women who want their fetus to enjoy optimal vitamin D levels, and the future health benefits that go along with it.
For example, taking only two of the hundreds of recently published studies, Professor Urashima and colleagues in Japan gave 1,200 IU/day of vitamin D3 for six months to Japanese 10 year-olds in a randomized controlled trial. They found vitamin D dramatically reduced the incidence of influenza A as well as the episodes of asthma attacks in the treated kids while the placebo group was not so fortunate. If Dr. Urashima had followed the newest FNB recommendations, it is unlikely that 400 IU/day treatment arm would have done much of anything and some of the treated young teenagers may have come to serious harm without the vitamin D. Likewise, a randomized controlled prevention trial of adults by Professor Joan Lappe and colleagues at Creighton University, which showed dramatic improvements in the health of internal organs, used more than twice the FNB's new adult recommendations.
Finally, the FNB committee consulted with 14 vitamin D experts and – after reading these 14 different reports – the FNB decided to suppress their reports. Many of these 14 consultants are either famous vitamin D researchers, like Professor Robert Heaney at Creighton, or in the case of Professor Walter Willett at Harvard, the single best-known nutritionist in the world. So, the FNB will not tell us what Professors Heaney and Willett thought of their new report? Why not? Yesterday, the Vitamin D Council directed our attorney to file a federal Freedom of Information (FOI) request to the IOM's FNB for the release of these 14 reports.
I, my family, most of my friends, hundreds of patients, and thousands of readers of the Vitamin D Council newsletter, have been taking 5,000 IU/day for up to eight years. Not only have they reported no significant side-effects, indeed, they have reported greatly improved health in multiple organ systems. My advice: especially for pregnant women, continue taking 5,000 IU/day until your (OH)D] is between 50 ng/ml and 80 ng/ml (the vitamin D blood levels obtained by humans who live and work in the sun and the mid-point of the current reference ranges at all American laboratories). Gestational vitamin D deficiency is not only associated with rickets, but a significantly increased risk of neonatal pneumonia (2), a doubled risk for preeclampsia (3), a tripled risk for gestational diabetes (4), and a quadrupled risk for primary cesarean section (5).
Yesterday, the FNB failed millions of pregnant women whose as yet unborn babies will pay the price. Let us hope the FNB will comply with the spirit of "transparency" by quickly responding to our freedom of Information requests.
The FNB also reported that vitamin D toxicity might occur at an intake of 10,000 IU/day (250 micrograms), although they could produce no reproducible evidence that 10,000 IU/day has ever caused toxicity in humans and only one poorly conducted study indicating 20,000 IU/day may cause mild elevations in serum calcium but not clinical toxicity.
Viewed with different measure, this FNB report recommends that an infant should take 10 micrograms/day (400 IU) and the pregnant women 15 micrograms/day (600 IU). As a single 30 minutes dose of summer sunshine gives adults more than 10,000 IU (250 micrograms), the FNB is apparently also warning that natural vitamin D input – as occurred from the sun before the widespread use of sunscreen – is dangerous. That is, the FNB is implying that God does not know what she is doing.
Disturbingly, this FNB committee focused on bone health, just like they did 14 years ago. They ignored the thousands of studies from the last ten years that showed higher doses of vitamin D helps: heart health, brain health, breast health, prostate health, pancreatic health, muscle health, nerve health, eye health, immune health, colon health, liver health, mood health, skin health, and especially fetal health. Tens of millions of pregnant women and their breast-feeding infants are severely vitamin D deficient, resulting in a great increase in the medieval disease, rickets. The FNB report seems to reason that if so many pregnant women have low vitamin D blood levels then it must be OK because such low levels are so common. However, such circular logic simply represents the cave man existence of most modern day pregnant women.
Hence, if you want to optimize your vitamin D levels – not just optimize the bone effect – supplementing is crucial. But it is almost impossible to significantly raise your vitamin D levels when supplementing at only 600 IU/day (15 micrograms). Pregnant women taking 400 IU/day have the same blood levels as pregnant women not taking vitamin D; that is, 400 IU is a meaninglessly small dose for pregnant women. Even taking 2,000 IU/day of vitamin D will only increase the vitamin D levels of most pregnant women by about 10 points, depending mainly on their weight. Professor Bruce Hollis has shown that 2,000 IU/day does not raise vitamin D to healthy or natural levels in either pregnant or lactating women. Therefore supplementing with higher amounts -- like 5000 IU/day -- is crucial for those women who want their fetus to enjoy optimal vitamin D levels, and the future health benefits that go along with it.
For example, taking only two of the hundreds of recently published studies, Professor Urashima and colleagues in Japan gave 1,200 IU/day of vitamin D3 for six months to Japanese 10 year-olds in a randomized controlled trial. They found vitamin D dramatically reduced the incidence of influenza A as well as the episodes of asthma attacks in the treated kids while the placebo group was not so fortunate. If Dr. Urashima had followed the newest FNB recommendations, it is unlikely that 400 IU/day treatment arm would have done much of anything and some of the treated young teenagers may have come to serious harm without the vitamin D. Likewise, a randomized controlled prevention trial of adults by Professor Joan Lappe and colleagues at Creighton University, which showed dramatic improvements in the health of internal organs, used more than twice the FNB's new adult recommendations.
Finally, the FNB committee consulted with 14 vitamin D experts and – after reading these 14 different reports – the FNB decided to suppress their reports. Many of these 14 consultants are either famous vitamin D researchers, like Professor Robert Heaney at Creighton, or in the case of Professor Walter Willett at Harvard, the single best-known nutritionist in the world. So, the FNB will not tell us what Professors Heaney and Willett thought of their new report? Why not? Yesterday, the Vitamin D Council directed our attorney to file a federal Freedom of Information (FOI) request to the IOM's FNB for the release of these 14 reports.
I, my family, most of my friends, hundreds of patients, and thousands of readers of the Vitamin D Council newsletter, have been taking 5,000 IU/day for up to eight years. Not only have they reported no significant side-effects, indeed, they have reported greatly improved health in multiple organ systems. My advice: especially for pregnant women, continue taking 5,000 IU/day until your (OH)D] is between 50 ng/ml and 80 ng/ml (the vitamin D blood levels obtained by humans who live and work in the sun and the mid-point of the current reference ranges at all American laboratories). Gestational vitamin D deficiency is not only associated with rickets, but a significantly increased risk of neonatal pneumonia (2), a doubled risk for preeclampsia (3), a tripled risk for gestational diabetes (4), and a quadrupled risk for primary cesarean section (5).
Yesterday, the FNB failed millions of pregnant women whose as yet unborn babies will pay the price. Let us hope the FNB will comply with the spirit of "transparency" by quickly responding to our freedom of Information requests.
29 November 2010
Garlic 'remedy for hypertension'
Garlic may be useful in addition to medication to treat high blood pressure, a study suggests.
Australian doctors enrolled 50 patients in a trial to see if garlic supplements could help those whose blood pressure was high, despite medication.
Those given four capsules of garlic extract a day had lower blood pressure than those on placebo, they report in scientific journal Maturitas.
The British Heart Foundation said more research was needed.
Garlic has long been though to be good for the heart.
Garlic supplements have previously been shown to lower cholesterol and reduce high blood pressure in those with untreated hypertension.
In the latest study, researchers from the University of Adelaide, Australia, looked at the effects of four capsules a day of a supplement known as aged garlic for 12 weeks.
They found systolic blood pressure was around 10mmHg lower in the group given garlic compared with those given a placebo.
Researcher Karin Ried said: "Garlic supplements have been associated with a blood pressure lowering effect of clinical significance in patients with untreated hypertension.
"Our trial, however, is the first to assess the effect, tolerability and acceptability of aged garlic extract as an additional treatment to existing antihypertensive medication in patients with treated, but uncontrolled, hypertension."
Experts say garlic supplements should only be used after seeking medical advice, as garlic can thin the blood or interact with some medicines.
Ellen Mason, senior cardiac nurse at the British Heart Foundation, said using garlic for medicinal purposes dates back thousands of years, but it is essential that scientific research proves that garlic can help conditions such as raised blood pressure.
She said: "This study demonstrated a slight blood pressure reduction after using aged garlic supplements but it's not significant enough or in a large enough group of people to currently recommend it instead of medication.
"It's a concern that so many people in the UK have poorly controlled blood pressure, with an increased risk of stroke and heart disease as a consequence. So enjoy garlic as part of your diet but don't stop taking your blood pressure medication."
Australian doctors enrolled 50 patients in a trial to see if garlic supplements could help those whose blood pressure was high, despite medication.
Those given four capsules of garlic extract a day had lower blood pressure than those on placebo, they report in scientific journal Maturitas.
The British Heart Foundation said more research was needed.
Garlic has long been though to be good for the heart.
Garlic supplements have previously been shown to lower cholesterol and reduce high blood pressure in those with untreated hypertension.
In the latest study, researchers from the University of Adelaide, Australia, looked at the effects of four capsules a day of a supplement known as aged garlic for 12 weeks.
They found systolic blood pressure was around 10mmHg lower in the group given garlic compared with those given a placebo.
Researcher Karin Ried said: "Garlic supplements have been associated with a blood pressure lowering effect of clinical significance in patients with untreated hypertension.
"Our trial, however, is the first to assess the effect, tolerability and acceptability of aged garlic extract as an additional treatment to existing antihypertensive medication in patients with treated, but uncontrolled, hypertension."
Experts say garlic supplements should only be used after seeking medical advice, as garlic can thin the blood or interact with some medicines.
Ellen Mason, senior cardiac nurse at the British Heart Foundation, said using garlic for medicinal purposes dates back thousands of years, but it is essential that scientific research proves that garlic can help conditions such as raised blood pressure.
She said: "This study demonstrated a slight blood pressure reduction after using aged garlic supplements but it's not significant enough or in a large enough group of people to currently recommend it instead of medication.
"It's a concern that so many people in the UK have poorly controlled blood pressure, with an increased risk of stroke and heart disease as a consequence. So enjoy garlic as part of your diet but don't stop taking your blood pressure medication."
Iron in Coronary Artery Plaque Is a Marker of Heart Attack Rick
Newswise — Plaque in a heart artery looks threatening, but cardiologists know that many of these buildups will not erupt, dislodge and block a vessel, causing a heart attack that can be fatal. Some will, however, and the challenge is to figure out atherosclerotic plaque that is dangerous and treat or remove it.
Now, researchers at Mayo Clinic have shown that iron, derived from blood, is much more prevalent in the kind of plaque that is unstable and is thus more likely to promote a myocardial infarction (MI) - heart attack - and possibly sudden death.
The team of researchers has demonstrated through a variety of experiments that iron buildup may be suitable as a marker of risk for a future MI, they reported today at the American Heart Association’s Scientific Sessions 2010 in Chicago.
For example, they have found that Dual Energy Computed Tomography (DECT) and three-dimensional computerized tomography (CT) micro scans can detect excess iron in plaque, thus holding promise that in the future a scanning device might be able to noninvasively detect dangerous plaque formations in patients.
“We know that 70 percent of heart attacks are caused by unstable plaque, so what we really need for our patients is a way to identify the plaque that turns evil and puts them at jeopardy,” says cardiologist Birgit Kantor, M.D., the study’s lead researcher. “The scans we use now just show narrowing of heart arteries from plaque buildup but that doesn’t tell us if the plaque inside those vessels walls is imminently dangerous.”
“We think it is possible, based on these findings, to use iron as a natural marker for risk,” she says. Dr. Kantor predicts that probably 5-10 years will pass before novel diagnostic scanners to identify these plaques become available in cardiology clinics.
Testing iron as a marker in human arteries
Excess iron in atherosclerotic plaque was noticed decades ago, but little research followed up on that observation, Dr. Kantor says. “The hypothesis then was that iron was the poison that created the plaque, but that was never proven and is in fact unlikely.”
Cardiologists now know that plaque can be classified as stable or unstable. Mayo Clinic researchers believe that the amount of iron in the plaque can be seen as a “readout” of prior hemorrhagic, or bleeding, events that put a person at risk for plaque eruption.
In normal heart arteries, small blood vessels known as vasa vasorum bring nutrients to the vessel wall, and when plaque starts to build up inside the artery wall, some of these tiny vessels grow as well to feed them. These vessels can rupture, depositing iron, a component of blood, into the growing plaque. This unstable plaque, which has a large core of dead cells covered by a thin fibrous cap, can eventually rupture, forming a big blood clot that can shut down a heart artery.
“This kind of plaque can bleed and heal, bleed and heal, depositing iron into the buildup,” Dr. Kantor says. “This plaque is at risk of breaking up and causing a heart attack.”
To conduct this study, the researchers used samples from a unique Mayo Clinic biobank of heart arteries collected over time from autopsies of 400 patients who died from a suspected heart attack. Small sections (1–1.5 inches) from the three main coronary arteries of each patient have been preserved.
In this study, pathologists examined 97 artery samples and separated them into stable and unstable groups based on their appearance under a microscope (dead zones and fiber cap). They classified 31 plaques as stable, 24 as “vulnerable,” and 22 as normal and then linked them to patient clinical records to see which patients died from a heart attack.
Then Yu Liu, M.D., Ph.D., the study’s first author, applied a stain to the samples to detect iron content. She found iron content in the unstable plaque group was significantly higher than in the other groups. Iron was absent in normal arteries.
In a third step, the researchers scanned a subset of the artery segments using a benchtop micro-CT scanner, and created 3-D images to look for iron deposits in plaque. The CT could identify iron in plaque without the need for staining. “There was a high correlation between the vulnerability of the plaque and the quantity of iron in it,” says Dr. Kantor.
Still, non-invasive imaging for plaque does not yet have the necessary resolution to differentiate high risk from low risk plaque in patients, she says, and so the research team is testing other imaging modalities such as photon counting that can overcome these barriers.
Now, researchers at Mayo Clinic have shown that iron, derived from blood, is much more prevalent in the kind of plaque that is unstable and is thus more likely to promote a myocardial infarction (MI) - heart attack - and possibly sudden death.
The team of researchers has demonstrated through a variety of experiments that iron buildup may be suitable as a marker of risk for a future MI, they reported today at the American Heart Association’s Scientific Sessions 2010 in Chicago.
For example, they have found that Dual Energy Computed Tomography (DECT) and three-dimensional computerized tomography (CT) micro scans can detect excess iron in plaque, thus holding promise that in the future a scanning device might be able to noninvasively detect dangerous plaque formations in patients.
“We know that 70 percent of heart attacks are caused by unstable plaque, so what we really need for our patients is a way to identify the plaque that turns evil and puts them at jeopardy,” says cardiologist Birgit Kantor, M.D., the study’s lead researcher. “The scans we use now just show narrowing of heart arteries from plaque buildup but that doesn’t tell us if the plaque inside those vessels walls is imminently dangerous.”
“We think it is possible, based on these findings, to use iron as a natural marker for risk,” she says. Dr. Kantor predicts that probably 5-10 years will pass before novel diagnostic scanners to identify these plaques become available in cardiology clinics.
Testing iron as a marker in human arteries
Excess iron in atherosclerotic plaque was noticed decades ago, but little research followed up on that observation, Dr. Kantor says. “The hypothesis then was that iron was the poison that created the plaque, but that was never proven and is in fact unlikely.”
Cardiologists now know that plaque can be classified as stable or unstable. Mayo Clinic researchers believe that the amount of iron in the plaque can be seen as a “readout” of prior hemorrhagic, or bleeding, events that put a person at risk for plaque eruption.
In normal heart arteries, small blood vessels known as vasa vasorum bring nutrients to the vessel wall, and when plaque starts to build up inside the artery wall, some of these tiny vessels grow as well to feed them. These vessels can rupture, depositing iron, a component of blood, into the growing plaque. This unstable plaque, which has a large core of dead cells covered by a thin fibrous cap, can eventually rupture, forming a big blood clot that can shut down a heart artery.
“This kind of plaque can bleed and heal, bleed and heal, depositing iron into the buildup,” Dr. Kantor says. “This plaque is at risk of breaking up and causing a heart attack.”
To conduct this study, the researchers used samples from a unique Mayo Clinic biobank of heart arteries collected over time from autopsies of 400 patients who died from a suspected heart attack. Small sections (1–1.5 inches) from the three main coronary arteries of each patient have been preserved.
In this study, pathologists examined 97 artery samples and separated them into stable and unstable groups based on their appearance under a microscope (dead zones and fiber cap). They classified 31 plaques as stable, 24 as “vulnerable,” and 22 as normal and then linked them to patient clinical records to see which patients died from a heart attack.
Then Yu Liu, M.D., Ph.D., the study’s first author, applied a stain to the samples to detect iron content. She found iron content in the unstable plaque group was significantly higher than in the other groups. Iron was absent in normal arteries.
In a third step, the researchers scanned a subset of the artery segments using a benchtop micro-CT scanner, and created 3-D images to look for iron deposits in plaque. The CT could identify iron in plaque without the need for staining. “There was a high correlation between the vulnerability of the plaque and the quantity of iron in it,” says Dr. Kantor.
Still, non-invasive imaging for plaque does not yet have the necessary resolution to differentiate high risk from low risk plaque in patients, she says, and so the research team is testing other imaging modalities such as photon counting that can overcome these barriers.
Vitamin C: A potential life-saving treatment for sepsis
Physicians caring for patients with sepsis may soon have a new safe and cost-effective treatment for this life-threatening illness. Research led by Dr. Karel Tyml and his colleagues at The University of Western Ontario and Lawson Health Research Institute have found that vitamin C can not only prevent the onset of sepsis, but can reverse the disease.
Sepsis is caused by a bacterial infection that can begin anywhere in your body. Your immune system goes into overdrive, overwhelming normal processes in your blood. The result is that small blood clots form, blocking blood flow to vital organs. This can lead to organ failure. Babies, the elderly and those with weakened immune systems are most likely to get sepsis. But even healthy people can become deathly ill from the disease.
According to Dr. Tyml, a professor at Western's Schulich School of Medicine & Dentistry, patients with severe sepsis have a high mortality rate, nearly 40 percent, because there is no effective treatment.
"There are many facets to sepsis, but the one we have focused on for the past 10 years is the plugging of capillaries," says Dr. Tyml. Plugged capillaries prevent oxygenation and the supply of life-supporting materials to your organ tissue and stop the removal of metabolic waste product. Plugged capillaries are seen in organs of septic patients. These organs may eventually fail, leading to multiple organ failure and death. Dr. Tyml's lab was the first to discover this plugging by using intravital microscopy, a technique Dr. Tyml pioneered in Canada.
According to Dr. Tyml's most recent publication, oxidative stress and the activated blood clotting pathway are the major factors responsible for the capillary plugging in sepsis. Through his research, Dr. Tyml has discovered that a single bolus of vitamin C injected early at the time of induction of sepsis, prevents capillary plugging. He has also found that a delayed bolus injection of vitamin C can reverse plugging by restoring blood flow in previously plugged capillaries.
"Our research in mice with sepsis has found that early as well as delayed injections of vitamin C improves chance of survival significantly," explains Dr. Tyml. "Furthermore, the beneficial effect of a single bolus injection of vitamin C is long lasting and prevents capillary plugging for up to 24 hours post-injection."
Dr. Tyml and his colleagues are eager to find appropriate support to move this research from the bench to the bedside to see if these findings translate to patients with sepsis.
The potential benefit of this treatment is substantial. "Vitamin C is cheap and safe. Previous studies have shown that it can be injected intravenously into patients with no side effects," says Dr. Tyml. "It has the potential to significantly improve the outcome of sepsis patients world-wide. This could be especially beneficially in developing countries where sepsis is more common and expensive treatments are not affordable."
Sepsis is caused by a bacterial infection that can begin anywhere in your body. Your immune system goes into overdrive, overwhelming normal processes in your blood. The result is that small blood clots form, blocking blood flow to vital organs. This can lead to organ failure. Babies, the elderly and those with weakened immune systems are most likely to get sepsis. But even healthy people can become deathly ill from the disease.
According to Dr. Tyml, a professor at Western's Schulich School of Medicine & Dentistry, patients with severe sepsis have a high mortality rate, nearly 40 percent, because there is no effective treatment.
"There are many facets to sepsis, but the one we have focused on for the past 10 years is the plugging of capillaries," says Dr. Tyml. Plugged capillaries prevent oxygenation and the supply of life-supporting materials to your organ tissue and stop the removal of metabolic waste product. Plugged capillaries are seen in organs of septic patients. These organs may eventually fail, leading to multiple organ failure and death. Dr. Tyml's lab was the first to discover this plugging by using intravital microscopy, a technique Dr. Tyml pioneered in Canada.
According to Dr. Tyml's most recent publication, oxidative stress and the activated blood clotting pathway are the major factors responsible for the capillary plugging in sepsis. Through his research, Dr. Tyml has discovered that a single bolus of vitamin C injected early at the time of induction of sepsis, prevents capillary plugging. He has also found that a delayed bolus injection of vitamin C can reverse plugging by restoring blood flow in previously plugged capillaries.
"Our research in mice with sepsis has found that early as well as delayed injections of vitamin C improves chance of survival significantly," explains Dr. Tyml. "Furthermore, the beneficial effect of a single bolus injection of vitamin C is long lasting and prevents capillary plugging for up to 24 hours post-injection."
Dr. Tyml and his colleagues are eager to find appropriate support to move this research from the bench to the bedside to see if these findings translate to patients with sepsis.
The potential benefit of this treatment is substantial. "Vitamin C is cheap and safe. Previous studies have shown that it can be injected intravenously into patients with no side effects," says Dr. Tyml. "It has the potential to significantly improve the outcome of sepsis patients world-wide. This could be especially beneficially in developing countries where sepsis is more common and expensive treatments are not affordable."
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