January 30, 2008
B2-microglobulin levels predict mortality in older individuals
The January 28, 2008 issue of the Archives of Internal Medicine reported the finding of Tokyo researchers that circulating levels of beta 2-microglobulin (B2-M) are associated with an increased risk of death during an eight year period among men and women aged 65 and older.
B2-microglobulin is an immune system molecule that is widely distributed in the nucleated cells of the body, and which occurs in higher levels in lymphocytes and monocytes (types of white blood cells). Because its concentration in the blood is largely affected by the kidneys' glomerular filtration rate, increased levels have been associated with kidney dysfunction. B2-microglobulin is also elevated in certain diseases, including some cancers, autoimmune disease and infection, due to increased production.
The current study included 1,034 men and women who were aged 65 to 89 upon enrollment in the Tokyo Metropolitan Institute of Gerontology Longitudinal Interdisciplinary Study on Aging. Medical examinations and participant interviews determined functional status, medical history, and other data. Blood samples collected at the beginning of the study were analyzed for serum B2-M, creatinine, cystatin C, and high-sensitivity C-reactive protein.
Over an average of 7.9 years of follow-up there were 223 deaths. Participants whose serum B2-M concentrations were in the top one-third of participants had nearly three times the risk of dying than those whose levels were in the lowest third, and those whose levels fell in the middle third experienced twice the risk. Participants whose cystatin C and C-reactive protein levels were highest also had a greater risk of dying than those whose were lowest, although the risk was not as great as that associated with high B2-M.
"Serum B2-M is an independent predictor of total mortality in a general population of older adults and may be a better predictor than cystatin C or CRP," the authors conclude.
January 28, 2008
Boswellic acid inhibits atherosclerotic lesions in mice
The February, 2008 issue of the American Heart Association journal Arteriosclerosis, Thrombosis and Vascular Biology reported the finding of researchers at the Institut National de la Sante et de la Research Medicale (INSERM) in France that treatment with boswellic acid inhibits the development of atherosclerosis in a mouse model of the disease.
Boswellic acid is derived from the resin of the Boswellia species, also known as frankincense. Acetyl-boswellic acids have been found to inhibit the signaling of nuclear factor-kappa beta (NF-kB), a transcription factor made by the body that initiates inflammation. "There is increasing recognition of the link between inflammation and atherosclerosis," the authors note.
The researchers induced atherosclerotic lesions in mice bred to develop atherosclerosis via weekly injections of lipopolysaccharide (LPS), an inflammation-promoting endotoxin. During this time, some of the animals were treated daily with a purified water-soluble acetyl-boswellic acid.
At the end of the treatment period, mice that did not receive boswellic acid experienced a 100 percent increase in atherosclerotic lesion size, while lesions in those that received boswellic acid grew by only 50 percent. Nuclear factor-kappa beta was reduced in the boswellic acid treated animals' plaques, and several NF-kB dependent genes involved in inflammation, including MCP-1, MCP-3, interleukin-1 alpha (IL-1a), MIP-2, vascular endothelial growth factor (VEGF), and tissue factor (TF) were downregulated.
Boswellic acid did not reduce the rise in cholesterol and triglycerides that accompanied lipopolysaccharide treatment, demonstrating that its effect on atherosclerotic lesions is due to other than lipid level reduction. The authors conclude that all of the data from the current study clearly indicate that boswellic acid reduced chronic inflammation in the mice through inhibition of the NF-kB system. "The inhibition of NF-kB by plant resins from species of the Boswellia family might represent an alternative for classical medicine treatments for chronic inflammatory diseases such as atherosclerosis," they suggest.
January 25, 2008
Meta-analysis finds hawthorn helps improve heart failure symptoms
A review published on January 23, 2008 in the Cochrane Library, a publication of the Cochrane Collaboration, concluded that consuming an extract of the leaves, flowers and fruit of hawthorn is associated with improvements in several measurements of function in patients with heart failure. Heart failure, which can be caused by clogged arteries which force the heart to work harder, is estimated to affect five million Americans. The condition results in enlargement of the heart and fluid buildup in the legs and lungs, which leads to shortness of breath and other symptoms.
For the meta-analysis, Cochrane researchers Dr Max H. Pittler, Dr Ruoling Guo and Edzard Ernst selected 10 double-blind randomized clinical trials of hawthorn that involved a total of 855 patients with mild to moderate chronic heart failure. The doses used in the trials ranged from 160 to 1800 milligrams standardized hawthorn extract. In some of the trials, the participants were also being treated with drugs for their condition, which included ACE inhibitors and diuretics.
The review found improved maximal workload, increased exercise tolerance, lowered cardiac oxygen consumption, and reduced shortness of breath and fatigue in heart failure patients that received hawthorn extract compared with those that received a placebo. Side effects, when experienced, were mild and short-lasting, and were absent in five of the trials.
According to Dr Pittler, who is the deputy director of complementary medicine at Peninsula Medical School in Exeter, England, hawthorn appears to increase the strength of heart contractions, improve arterial blood flow, and reduce irregular beats. "If I had chronic heart failure, I certainly would consider it,” he remarked.
“There is good evidence that, when used alongside conventional therapy, hawthorn extract can bring additional benefits,” lead researcher Dr Guo concluded
January 23, 2008
Long-term aspirin users have a lower risk of colorectal cancer
The January, 2008 issue of the journal Gastroenterology reported the finding of researchers at Massachusetts General Hospital and Harvard University that regular long-term users of aspirin have a reduced risk of colorectal cancer compared with those who don't use the drugs. Unfortunately, the doses associated with the lowest risk are higher than those commonly recommended for long term use for the prevention of cardiovascular and other diseases, and might increase the risk of gastrointestinal bleeding.
The current study included 47,636 participants in the Health Professionals Follow-up Study, a prospective cohort study of 51,529 male dentists, osteopaths, podiatrists, pharmacists and veterinarians aged 40 to 75 upon enrollment in 1986. Participants completed questionnaires concerning aspirin use, medical diagnoses, and other factors at the beginning of the study and every two years thereafter for eighteen years.
By the end of the follow-up period 975 cases of colorectal cancer had been diagnosed. Adjusted analysis of the data determined that regular use of aspirin, defined as two or more aspirin per week, was associated with a significantly lower risk of colorectal cancer, including distal, proximal, early stage and advanced stage colon cancer, as well as rectal malignancies. Significant risk reduction was not evident until aspirin had been used regularly for six to ten years and disappeared four to five years after the drug was discontinued. The greatest reduction was associated with consuming at least 14 standard sized 325 milligram tablets per week. Men who reported this level of aspirin use experienced a 70 percent lower risk of colorectal cancer compared with men who reported no aspirin use.
“These data support the need to further characterize those for whom the potential benefits of aspirin outweigh the hazards and to improve our understanding of the mechanisms by which aspirin inhibits carcinogenesis," the authors conclude.
January 21, 2008
Increased carotene intake associated with reduced cardiovascular mortality
The February, 2008 issue of the Journal of Nutrition published the results of a study conducted by researchers at Wageningen University in The Netherlands which found a reduction in deaths caused by cardiovascular disease over a 15 year period among older men with a high intake of alpha and beta-carotene.
The researchers utilized data from 559 participants in the Zutphen Elderly Study, a prospective cohort study conducted in the Netherlands. Men participating in the study were an average of 72 years old upon enrollment, and were followed for 15 years. Subjects included in the current analysis were free of cardiovascular disease, diabetes and cancer at the beginning of the study. Information on dietary intake collected in 1985, 1990, and 1995 was analyzed for intake levels of carotenoids, vitamin C, tocopherols, and other nutrients.
At the end of the follow-up period, there were 89 deaths from ischemic heart disease, 52 deaths from stroke, and 56 from other cardiovascular causes. The researchers found a reduction in cardiovascular deaths associated with alpha-carotene and beta-carotene, as well as for carrots, an abundant source of these nutrients. There were no associations found between death from cardiovascular disease and any of the other nutrients analyzed.
In their discussion of the findings, the authors remark that both alpha and beta-carotene are important antioxidants, and that lipoprotein oxidation caused by reactive nitrogen species within the arterial wall may preferentially deplete these carotenes and other fat-soluble antioxidants, resulting in increased susceptibility of lipoprotein to oxidation when intake of the carotenes are low. Circulating carotenoids have also been shown to be associated with a reduction in inflammation and improved endothelial function. "More observational studies on the intake of individual carotenoids and their specific sources, as well as foods correlated with their intake, in relation to cardiovascular disease are warranted," the authors conclude.
January 18, 2008
Vitamin D supplementation reduces women's risk of falling
The January 14, 2008 issue of the Archives of Internal Medicine revealed the finding of Australian researchers that women with a history of falls who consumed vitamin D supplements have a lower risk of falling than women who did not receive the vitamin, particularly during winter, when sunlight exposure is lower. Approximately one-third of women older than 65 years fall each year, 6 percent of whom sustain a fracture.
Richard L. Prince, MD, of the Sir Charles Gairdner Hospital, in Nedlands, Australia, and colleagues randomized 302 women aged 70 to 90 whose vitamin D levels were less than 24 nanograms to receive 1,000 international units vitamin D2 (ergocalciferol) or a placebo for one year. Both groups received 500 milligrams calcium twice daily. Data on falls was collected every six weeks.
Fifty-three percent of those who received vitamin D experienced a fall over the course of the study, compared with 62.9 percent of those who received the placebo. When those who fell were analyzed by the season during which their first fall occurred or the number of falls they experienced, vitamin D was found to lower the risk of experiencing a first fall during winter and spring, but not summer and autumn, and to reduce the risk of experiencing a first fall, but not multiple falls. Serum measurement of 25-hydroxyvitamin D found a 28 percent higher level of of the vitamin during winter/spring among those who received vitamin D, and a 12.5 higher level during summer and autumn compared with the placebo group. For the placebo group, vitamin D status only improved during the summer.
The authors conclude that “Ergocalciferol, 1,000 international units per day, added to a high calcium intake is associated with 23 percent reduction of the risk of falling in winter/spring to the same level as in summer/autumn.”
January 16, 2008
Cranberries, woman's best friend
Research conducted by Tel Aviv University professor Itzhak Ofek and his colleagues is revealing a surprising array of benefits for cranberries. Long known to be helpful for the prevention of urinary tract infections, Dr Ofek has discovered that cranberry juice can help prevent cavities, fight influenza, and reduce the recurrence of gastric ulcers. However, the berries appear to provide a greater benefit to women than men.
A letter published in the May 30, 1991 issue of the New England Journal of Medicine discussed Dr Ofek's team's finding that a compound found in the berries known as non-dialyzable material or NDM appears to coat some of the body's surfaces which prevents the adherence of infectious agents while not affecting the body's beneficial bacteria. “We understood that there was something in cranberry juice that doesn’t let infections adhere to a woman’s bladder," Dr Ofek said. "We figured it was a specific inhibitor and proved this to be the case.”
Following this work, a trial at Tel Aviv University’s School of Dental Medicine revealed other benefits for the berry. "We found that NDM inhibits adhesion of oral bacteria to tooth surfaces and as a consequence reduced the bacterial load that causes cavities in the mouth.” Dr Ofek explained.
And in the June, 2007 issue of Molecular Nutrition & Food Research, an article coauthored by Dr Ofek describes the effect of cranberries on the eradication of H. Pylori, the bacteria that causes ulcers, when combined with standard drug treatment. The report concluded that, "The addition of cranberry to triple therapy improves the rate of H. pylori eradication in females."
“The whole thing with cranberries seems to be female-oriented,” Dr Ofek noted. “The take-home message is that God created this fruit with a polyphenolic material. We still don't know its chemical formula, but it seems to target a fraction of bacteria and viruses.”
January 14, 2008
Scientists achieve record extension of life span in simple organism
In an article scheduled to appear in the January 25, 2008 issue of the journal PLoS Genetics, researchers at the University of Southern California report that a combination of dietary restriction and knocking out two genes resulted in baker's yeast living ten times longer than their normal life span. The yeast in the study survived the equivalent of 800 yeast years without any adverse effects.
University of Southern California associate professor in gerontology Valter Longo, PhD and associates knocked out FAS2 and SCH9, which are genes that had been found to promote aging in yeast as well as in humans with Werner/Bloom syndromes, diseases characterized by accelerated aging and an increased incidence of cancer. A companion study, which will appear in the January 14, 2008 issue of the Journal of Cell Biology, revealed that these same genetic knock outs reversed a yeast model of the diseases. Dr Longo's group is currently studying a human population in Ecuador with similar mutations.
“People with two copies of the mutations have very small stature and other defects,” Dr Longo observed. “We are now identifying the relatives with only one copy of the mutation, who are apparently normal. We hope that they will show a reduced incidence of diseases and an extended life span.”
Previous research, published in the July 27, 2007 issue of Cell, found that mice with a mutation initially identified by Dr Longo's team survived 30 percent beyond their normal life span while being protected from osteoporosis and aging-induced cardiomyopathy.
Dr Longo cautioned that longevity mutations can be accompanied by health problems, and expressed the hope that researchers use the knowledge gained in these studies "in a fairly limited way, to reprogram disease prevention."
“We’re setting the foundation for reprogramming healthy life," he said.
January 11, 2008
Wine polyphenols reduce damage caused by fatty food
For centuries, many people have considered wine to be an essential component of a satisfying meal. In the January, 2008 issue of the Journal of The Federation of American Societies for Experimental Biology (FASEB), Israeli researchers reveal a new reason why drinking wine with meals may be healthy as well as pleasurable.
Joseph Kanner of the Volcani Center in Bet Dagan, Israel and his associates gave six men and four women meals consisting of dark turkey meat and water, turkey meat and polyphenols in the form of concentrated wine added after cooking, followed with a glass of red wine; or turkey meat soaked in wine polyphenols before cooking, followed by a glass of wine. Polyphenols are compounds that naturally occur in red grapes and wine which have been shown to have a number of health-protecting benefits.
Blood and urine samples obtained before and after the meal were analyzed for levels of malondialdehyde (MDA), a by-product of fat digestion which increases the risk of heart disease and other conditions. While the participants' MDA levels nearly quintupled following the meal that did not contain wine polyphenols, those who consumed the meal in which polyphenols were added before cooking experienced no increase. The meal in which polyphenols were added after cooking was nearly as effective.
“We suggest a new hypothesis to explain polyphenols,” Dr Kanner stated “For the first time, these compounds were demonstrated to prevent significantly the appearance of toxic food derivative compounds in human plasma.”
“As long as deep fried candy bars are on menus, scientists will need to keep serving up new ways to prevent the cellular damage caused by these very tasty treats,” Gerald Weissmann, MD, Editor-in-Chief of The FASEB Journal added. “This study suggests that the time will come where people can eat french fries without plugging their arteries.”
January 09, 2008
How does an extra fourteen years sound?
A report published online on January 8, 2008 in PLoS (Public Library of Science) Medicine concluded that individuals who adopt just four healthy behaviors live an average of fourteen years longer than those who don't.
For the current study, Kay-Tee Khaw and associates at the University of Cambridge and the Medical Research Council in Cambridge, England examined data from 20,244 participants in the European Prospective Investigation into Cancer and Nutrition (EPIC) Norfolk study which enrolled men and women between the ages of 45 and 79 who were free of cancer or cardiovascular disease between 1993 and 1997. Questionnaires completed by the participants awarded one point each for not smoking, being physically active, consuming alcohol in moderation (defined as 1 to 14 units per week), and having a plasma vitamin C level consistent with eating five servings of vegetables or fruit per day. The subjects were followed until 2006, during which time any deaths were recorded.
It was determined that those who scored no points on the questionnaires were four times as likely to die over the follow-up period than those who scored 4 points, and those with a score of 2 were twice as likely to have died. The research team found that participants whose score was 0 had the same risk of dying as subjects who were 14 years older who had practiced all four healthy behaviors. Adjustment of the results for body mass index and age failed to modify the finding.
The study's results emphasize the impact of a few combined behavioral changes on on longevity. "These results may provide further support for the idea that even small differences in lifestyle may make a big difference to health in the population and encourage behavior change," the authors conclude.
January 07, 2008
A grape way to fight cavities
An article published online on November 14, 2007 in the Journal of Agricultural and Food Chemistry revealed the discovery of researchers at the University of Rochester and Cornell University that polyphenols in red grapes may reduce the ability of bacteria to cause tooth decay.
Hyun Koo, DDS, PhD, who is an assistant professor of Dentistry in the Eastman Department of Dentistry and Center for Oral Biology at Rochester University Medical Center, and his associates extracted polyphenols from several varieties of red wine as well as from pomace, which consists of fermented seeds and skins that are discarded after grapes are pressed. The extracts were tested for their ability to reduce the virulence of Streptococcus mutans, the bacteria that causes cavities.
All of the polyphenol extracts tested were found to inhibit glucosyltransferases (GTFs) B and C, bacterial enzymes that produce glucans which attach bacteria to tooth surfaces to form the dental biofilm known as plaque. Polyphenols derived by Cabernet Franc extracts were found to be the most effective by inhibiting 85 percent of these enzymes. Additionally, polyphenols reduced the ability of Streptococcus mutans to secrete acid, which enhances its survival. "Overall, the phenolic extracts disrupt essential virulence traits for a widespread, destructive oral pathogen, but without killing it," commented research team member Olga I. Padilla-Zakour, PhD, of Cornell. "We are excited about the potential application of active compounds from wine grape by-products in the control of biofilms as part of the precise targeting of bacterial disease."
“Most foods contain compounds that are both good and bad for dental health, so the message is not ‘drink more wine to fight bacteria,’” Dr Koo advised. “We hope to isolate the key compounds within the winemaking waste that render bad bacteria harmless, perhaps in the mouth with a new kind of rinse.”
January 04, 2008
N-acetylcysteine improves non-acetaminophen induced acute liver failure recovery in children
A report published in the January, 2008 issue of the journal Liver Transplantation described the finding of researchers at King’s College Hospital in London that N-acetylcysteine (NAC), an amino acid used to treat acute liver failure caused by acetaminophen toxicity, also aids in the recovery from non-acetaminophen induced acute liver failure.
N-acetylcysteine is an antioxidant that replenishes glutathione stores in the mitochondria and cytosome of the cell. While widely used for many years to treat acetaminophen-induced liver failure, NAC was introduced at King's College Hospital in 1995 as a treatment for acute liver failure not caused by the drug.
Christine Kortsalioudaki and colleagues evaluated the medical records of 170 King's College Hospital patients under the age of eighteen who were treated for non-acetaminophen induced acute liver failure. Children who received intravenous NAC along with standard care were compared with those who received standard care only.
Ten year survival was 75 percent among children who received NAC compared with 50 percent of those who received standard care only. The team found that 43 percent of those who received NAC survived with their own liver, compared with 22 percent of those who did not receive the compound. Sixteen percent who received NAC died following liver transplant, compared with 39 percent of those who received standard care. Treatment with N-acetylcysteine was also linked with shorter hospital stays, and fewer and shorter intensive care stays.
“Our data demonstrates that NAC has minor, self-limited adverse effects and can be safely administered to children with non-acetaminophen induced acute liver failure,” the authors write. “Additionally this study suggests NAC may have a positive effect on the outcome of non-acetaminophen induced acute liver failure, improving the survival with native liver as well as post liver transplant survival.”
January 03, 2008
Scientists discover how fish oil helps protect the brain from Alzheimer's disease
The December 26, 2007 issue of The Journal of Neuroscience reported the finding of Greg Cole and colleagues at the University of California, Los Angeles of a mechanism by which the omega-3 fatty acid docosahexaenoic acid (DHA), found in fish oil, helps prevent Alzheimer's disease. Research has suggested a protective effect for fish oil against Alzheimer's disease and dementia, but the mechanisms responsible for this benefit had not been determined.
Dr Cole, who is a professor of medicine and neurology at UCLA's David Geffen School of Medicine, and his colleagues found that DHA increases the production of a protein known as LR11, which is reduced in Alzheimer's disease patients. LR11 decreases the formation of beta amyloid, a protein that forms brain plaques which characterize the disease.
Dr Cole's team was able to confirm DHA's effect by adding fish oil or DHA to the diet of rodents, or applying it to rat neurons. "We found that even low doses of DHA increased the levels of LR11 in rat neurons, while dietary DHA increased LR11 in brains of rats or older mice that had been genetically altered to develop Alzheimer's disease," Dr Cole stated. DHA was also shown to increase LR11 when administered to cultured human neurons.
What the research team has yet to determine "is what the optimal dose should be," Dr Cole noted. "It could be that a smaller amount might be helpful, especially in a place like the south of France, where people are already on a Mediterranean diet."
However, in the United States, where fish consumption is low, a greater dose may be needed. "There's a deficiency of DHA to begin with," Dr Cole stated, "and this may contribute to the low LR11 seen in many Alzheimer's patients."
What's Hot Archive