Gene find helps show how eating a lot less could extend life

Scientists have identified a gene which helps to explain how drastically reducing food intake can extend lifespan. The discovery suggests that calorie restriction, which has been shown to work in animals, may also be beneficial to humans. It also opens the door for the development of drugs which could mimic the advantages of eating less without the need for people to alter their diets.

Until now, there has been scant evidence to suggest that calorie restriction diets extend human lives. But this has not stopped more than 1,000 people around the world from joining the Calorie Restriction Society, a California group which promotes the idea that eating less than half the recommended 2,000 calories a day can switch on physiological changes that slow the ageing process.

Experiments in the early 1930s showed that calorie-restricted laboratory animals lived longer and had a lower risk of cancer, diabetes and cardiovascular disease.

To get the life enhancement benefits, diets have to be restricted to 60-70% of the calories of normal food intake. "Dietary restriction is one of the universal forms of increasing longevity and this has been shown in everything ranging from yeast all the way up to dogs," said Andrew Dillin, of the Salk Institute for Biological Studies in California. By using genetically modified variants of the nematode worm - Caenorhabditis elegans - Professor Dillin's team found that the pha-4 gene was a key part of the life-enhancing response to restricting diet. Prof Dillin said that the results, published today in Nature, lay down "the cornerstone of defining the molecular pathway that responds to reduced food intake that results in increased longevity".

Pha-4 is the first gene to be exclusively linked to extending lifespan in response to calorie restriction in animals. Prof Dillin speculated that pha-4, which has an analogue in mice and humans with the Foxa family of genes, probably evolved to protect animals when food was scarce.

He said that it was unclear whether restricting diets would necessarily increase lifespan in humans. But he added: "The primate study that's going on right now, and is 35 years in, looks like the primates are going to respond very well to reduced food intake and going to live longer." As part of their experiment, the scientists also stimulated the pha-4 gene in the worms so that it worked harder than normal. They found that the worms could mimic the life-enhancing effects of dietary restriction without needing to restrict calories.

Prof Dillin said that the findings opened up new avenues of research to extend life in more complex animals. "Can people eat their normal diets but really ... enjoy the benefits of dietary restriction without having to go through the whole regimen?"
Source : http://www.guardian.co.uk

Study sees good news in heart treatment

Increased use of angioplasty and the introduction of new drugs over the last six years have nearly halved the number of hospitalized heart attack victims who die or suffer severe heart failure, an international team of researchers reports Wednesday.

"There have been a lot of lives saved, a lot of complications averted," said Dr. Joel Gore of the University of Massachusetts Medical School, one of the study's leaders.

The group could not attribute the improved outcomes to any one treatment or medication, concluding it was the total of all combined that was responsible.

The report showed "remarkable improvements" in the care of heart attack victims in all 14 countries studied, said Dr. Gregg Fonarow, a UCLA cardiology specialist, who was not involved in the study.

"It is not simple to manage these patients. Many therapies need to be applied very rapidly," Fonarow said. This study shows that individual drugs and treatments that have been validated in clinical trials can be combined in the real world to produce "meaningful benefits."

Added Dr. Keith Fox of the University of Edinburgh in Scotland, who led the study published in the Journal of the American Medical Association: "Our study supports the fact that hospitals are using new treatments effectively."

For every 1,000 patients admitted to hospitals, he said, there are 39 fewer deaths and 90 fewer patients with new heart failures compared with only six years ago.

The study, called the Global Registry of Acute Coronary Events, or GRACE, enrolled 44,372 patients at 113 hospitals from 1999 to 2006. All the patients had had a severe heart attack or suffered from acute coronary syndrome, which includes other types of heart attacks and a kind of chest pain called unstable angina.

Death rates from severe heart attacks while in the hospital were reduced to 4.5 percent at the end of the study from 8.4 percent at the beginning, according to the report.

The study was funded by the pharmaceutical company Sanofi-Aventis through an unrestricted educational grant to the University of Massachusetts to maintain the GRACE registry. Most of the authors have received funds from pharmaceutical companies.

Source : http://www.chicagotribune.com

FDA urges young adult warning on antidepressants

Warnings on antidepressant drugs should be expanded to say the risks of suicidal thoughts and behavior extend to adults ages 18 to 24, U.S. health officials said on Wednesday.

The danger decreases, however, for adults 65 and older when they take the medicines, the Food and Drug Administration said. New warning labels should note that finding and stress that depression and some other psychiatric disorders are themselves a major causes of suicide, officials said.

The drugs already come with strong warnings that taking them may increase the chances of suicidal thoughts or actions in children and teenagers. Many psychiatrists have criticized the warnings, saying they scare people away from effective treatment and may have contributed to an increase in suicide in recent years.

Millions of Americans take antidepressants. The drugs include Wyeth's Effexor, Pfizer Inc.'s Zoloft, GlaxoSmithKline Plc's Paxil, Eli Lilly and Co's Prozac and Cymbalta, and Forest Laboratories Inc.'s Lexapro.

The FDA reviewed 295 studies of various antidepressants that included more than 77,000 adults.

The analysis found a "slight increase" in suicidal thinking and behavior among young adults during early treatment, which was generally the first one to two months, the FDA said. The data did not find a higher risk for adults older than 24.

For every 1,000 patients treated, about five more cases of suicidal thoughts and actions were reported among 18- to 24-year-olds who took the drugs rather than a placebo.

"The risk is quite small, but we think it is a real risk and it's something that needs to be paid attention to," Dr. Thomas Laughren, director of the FDA's division of psychiatry products, told reporters.

Fourteen additional cases were seen in patients under 18 who took antidepressants. For people 65 and older, there were six fewer cases.

Patients of any age who start taking antidepressants should be monitored for worsening depression, suicidal actions or unusual changes in behavior, FDA officials said. Anyone now taking one of the drugs should not stop, but should consult a doctor if they have concerns, they said.

Some psychiatrists have urged the FDA to remove or revise the warnings for children, which are highlighted in a "black box," the most serious type of warning for prescription drugs.

Prescriptions dropped after the warning for children and teens was added in 2004. The cautions about adults would be added to that warning.

The American Psychiatric Association said it was pleased the FDA now wanted the black box to note that depression itself may lead to suicide.

Dr. Carolyn Robinowitz, the group's president-elect, said the revised warning was "a major step in the right direction."

"We believe the new label, which still contains important warning information, reminds physicians and patients that antidepressants save lives," she said.

Researchers who published a study in April in the Journal of the American Medical Association said they found the benefits of antidepressants for children and teens far outweighed the risk of suicidal thoughts and behavior.

Pfizer will add the new warning for young adults to the Zoloft label, company spokeswoman Shreya Prudlo said. She added "there is no established causal link between Zoloft and suicide in adults, young adults or children."

Officials at Lilly, Forest and Wyeth also said the companies would add the new warnings to their products.

Source : http://www.sciam.com

'Food safety czar' named

The Bush administration appointed a new "food safety czar" yesterday and directed him to develop a plan for addressing shortcomings exposed by recent scares in the human food supply.

Dr. David W.K. Acheson, a former University of Maryland medical school professor who had been chief medical officer at the Food and Drug Administration's food safety center, immediately stepped into the job.

The creation of the new position underscored the extent of public concern about the country's food safety system over a dangerous chemical found in pet food entering the human food supply, in addition to recent outbreaks of bacterial contamination in bagged spinach, Taco Bell lettuce and Peter Pan peanut butter. But Democrats said fears have intensified to a degree that a new appointment alone won't quell.

Acheson's first order of business will be to devise a strategy for addressing changes to the country's food supply, such as its increasing dependence upon imports from nations with varying degrees of safety vigilance.

"We've seen a rapid transformation of the food safety system due to advances in production technology, rapid methods of distribution and the globalization of food sources," FDA Commissioner Andrew C. von Eschenbach said in a statement. He said Acheson's experience and knowledge would help the FDA "keep pace" with the changes.

One thing Acheson said he wanted to take a look at is the agency's system for deciding which food to closely monitor. The FDA has enough inspectors to examine just 1 percent of imports, so it tries to determine the riskiest products worthy of inspectors' close attention.

But the tainted pet food ingredient wasn't among the high-risk products, prompting Acheson to say he would look at how the agency identifies risk. "We're in the process of re-examining that whole scenario," he said.

FDA challenges
The appointment came just before the House Oversight and Government Reform Committee held a hearing on the challenges facing the FDA, including protecting the food supply, that was attended by three former agency commissioners.

Dr. David A. Kessler, FDA commissioner under former Presidents George Bush and Bill Clinton, called the food safety system "broken" and said the FDA needs to restore research and other efforts to prevent foodborne illness.

"The FDA can react to outbreaks, but the emphasis needs to be on preventing outbreaks before they happen," he said.

Von Eschenbach vowed to work with other agencies and countries to prevent future outbreaks, and he challenged Kessler's characterization. "Our food safety system in this country is not broken," he said.

Republicans and Democrats have taken turns recently questioning the capabilities of the country's food safety system. Several Democrats, who began proposing food safety legislation, dismissed the creation of a food safety czar as insufficient to fix the gaps exposed by the pet food scare.

"I don't think that's going to get the job done," said Sen. Richard J. Durbin, the second-ranking Democrat in the Senate. The FDA "needs additional resources - that is, more inspectors - and more legal authority."

Food safety rules
Durbin said he has requested as much additional funding as possible for the FDA. He said he was working with fellow senators sponsoring drug safety legislation to add provisions requiring states to adopt consistent food safety standards and penalizing companies that fail to promptly report food contamination.

The Illinois senator had been urging Congress to give the FDA authority to order companies to recall tainted products - now, companies must agree - but Durbin said he has dropped the demand for the time being to increase the chances that the Senate will enact some food safety improvements.

Acheson moved to the University of Maryland School of Medicine from Tufts University in 2001. He was an associate professor studying E. coli before transferring the next year to the FDA, according to the agency. Medical school faculty did not return calls seeking comment.

During a conference call with reporters updating the pet food contamination, Acheson, 51, declined to answer what was different about his new job. "The goal is to develop a strategic way of thinking, moving into the future, acknowledging there has been change," he said.

The scare has led to one of the largest recalls of pet food products, more than 150 brands. Melamine, a plastic derivative not approved for use in food, was first discovered in wheat gluten added to thicken dog and cat food. The chemical and related compounds have since turned up in feed for hogs and now poultry.

Investigators have linked melamine to the deaths of cats and dogs, although previous studies had not found the chemical toxic.

The melamine came from China. Investigators believe Chinese producers of wheat gluten laced it with melamine to boost the price. Inspectors are now stopping all wheat gluten imports from China.

Investigators had collected 750 samples as of Thursday, and 330 tested positive for melamine or related compounds so far, according to an FDA import alert, published on the agency Web site.

FDA investigators met with Chinese government officials and intend to visit Chinese factories that manufacture wheat gluten and other vegetable protein products added to foods. They are facing delays because it is a holiday in China, FDA officials said.

Source : http://www.baltimoresun.com

High Calcium, Vitamin D Intake May Harm Aging Brain

Seniors who consume high levels of calcium and vitamin D are much more likely to have larger brain lesions that can lead to cognitive impairment, depression or stroke, new research reveals.

The study authors point out that brain lesions of various sizes are not uncommon, even among healthy elders. However, the observation that the overall amount of brain matter affected by lesions goes up with vitamin intake is fueling concerns about a possible connection.

"This is one of the first studies to examine the relationship between diet and brain lesions," said study author Martha E. Payne, an assistant professor in the department of psychiatry and behavioral sciences with the Neuropsychiatric Imaging Research Laboratory at Duke University, in Durham, N.C.

"Since our study only looked at diet and brain lesions at one point in time, we cannot conclude that calcium or vitamin D caused the brain lesions that we found," she cautioned. But she added that "our finding of a relationship between brain lesions and consumption of both calcium and vitamin D raises the question about a possible downside to high intakes of these nutrients."

However, one nutritionist said it's still far too early to warn people away from calcium and vitamin D, which is vital to bone health. "In general, the problem is that people don't have enough intake of vitamin D and calcium, not too much," said Susan Harris, a nutritional epidemiologist and scientist at the U.S. Department of Agriculture Nutrition Center at Tufts University, in Boston.

Payne's team released its results Tuesday as part of an American Society for Nutrition presentation at the Experimental Biology 2007 meeting, in Washington D.C.

The researchers conducted their work against the backdrop of public health messages that urge older Americans to take in calcium and vitamin D to ward off bone loss.

The authors note that calcium is also known to be important to proper nerve and muscle cell function.

According to the National Osteoporosis Foundation, vitamin D3 and calcium deficiency is a global problem. The organization's most recent scientific statement recommends that adults over the age of 50 consume 1,200 milligrams of calcium daily. A daily total of 800 to 1,000 I.U. of vitamin D3 is also suggested, although the foundation cautions that supplementation at that level should only be taken with a doctor's supervision.

In addition to ingesting it in supplement form, calcium can be found naturally in milk, cheese and broccoli, and is often added to fortify foods such as orange juice, cereals and breakfast bars.

Vitamin D, key to good calcium absorption, is produced by the skin following exposure to the sun, although production decreases with age. Vitamin D is also found in foods such as saltwater fish, liver and dairy products.

Payne's current work follows her earlier exploration into a similar association between large brain lesions and high intake of high-fat dairy products.

Having ruled out fat as the link between diet and lesions, Payne shifted her analysis towards calcium and vitamin D.

The researchers looked at MRI brain scans from 232 men and women, aged 60 to 86, all of whom showed brain lesions of varying sizes.

The scans were taken as part of a larger study on late-life depression. As a result, nearly half the participants were diagnosed with depression.

In addition to mental health status, vitamin D and calcium intake habits were noted along with age and blood pressure readings.

The researchers found that, even after accounting for all other mitigating factors, a "strong relationship" seemed to exist between total lesion volume and vitamin D and calcium consumption.

Payne and her associates believe the link may lie in an excess absorption of calcium by blood vessel walls. These could form bone-like deposits that narrow blood vessels and restrict elasticity. Excess vitamin D might exacerbate that process, they added.

In turn, blood vessel damage, if it were to occur in the brain, could lead to the development of brain lesions, they theorized.

Given that "higher intakes of calcium and vitamin D have been promoted in recent years as a way to prevent bone loss with aging", Payne said that more in-depth study is urgently needed to further test such possible explanations for the observed vitamin-lesion link.

But Harris said that no one should be unduly alarmed by the current findings, at least for the time being.

"You wouldn't want to change your intake of calcium and vitamin D based on this study," she advised. "It may generate some hypotheses that are worth testing, but at this point the research can't really speak to whether the brain lesions were related to the calcium, vitamin D, or some other factor that people with high intakes of calcium and vitamin D also have."
Source : http://www.forbes.com

Migraine during pregnancy ups risk of stroke

Women who suffer migraine headaches while pregnant are at increased risk for suffering a heart attack, stroke or other "vascular" event, according to research presented at the annual meeting of the American Academy of Neurology underway in Boston.

"Women with persistent migraine during pregnancy should be aware of their risk factors, such as high blood pressure, high cholesterol, diabetes, history of blood clots, heart disease, and prior stroke," said Dr. Cheryl Bushnell from Duke University, Durham, North Carolina.

There also seems to be a connection between migraine headache during pregnancy and preeclampsia, the most common and dangerous complication of pregnancy. "Good prenatal care is essential," Bushnell said.

Among nearly 17 million women with a pregnancy-related discharge from US hospitals during a 3-year period (2000-2003), a total of 33,956 women were treated for migraine during their pregnancy.

Women who were 35 or older when they delivered were more likely to have migraines than were younger women.

"We also found that there was a very close association between migraine and vascular disease," Bushnell said at a gathering of reporters at the meeting.

Women treated for migraine during pregnancy were 19 times more likely to suffer a stroke, five times more likely to have a heart attack and more than twice as likely to have heart disease, blood clots and other vascular problems. They were also more than twice as likely to develop preeclampsia or high blood pressure related to their pregnancy.

Risk factors for vascular disease such as diabetes, high blood pressure and smoking were also associated with experiencing migraine headache during pregnancy.

Previous research has linked migraine with stroke and cardiovascular disease in older women. The current study now supports the same association in women who are pregnant, Bushnell said.

"I don't think that we should assume that just because they are young and pregnant that they are not at risk for having a vascular event," she told Reuters Health.

Source : http://www.reuters.com

Testosterone cream fails as sex drive booster

Testosterone cream does not appear to boost the sex drives of women cancer survivors suffering from low libido, a new study shows.

"The idea is that libido is probably more complicated than just testosterone alone," Dr. Debra L. Barton of the Mayo Clinic College of Medicine in Rochester, Minnesota, the study's lead author, told Reuters Health. "It's a complicated issue that's probably going to take a broader, more complicated solution."

Some studies have found testosterone cream can help restore sexual interest in women with low libido, Barton and her team note in a report in the Journal of the National Cancer Institute this week.

They conducted the study to determine if the hormone cream could also be helpful to female cancer survivors, who frequently experience a drop in sex drive, especially after treatment for breast or gynecologic cancers.

The researchers randomized 150 women to receive the testosterone cream or a placebo cream for four weeks, after which they were switched to the opposite treatment for an additional four weeks.

While women given testosterone showed an increase in blood levels of the hormone, their change in libido was the same whether they were on the real testosterone cream or the placebo.

All studies in which testosterone cream was found to help increase libido were conducted in postmenopausal women taking estrogen, the researchers note. But because women in the current study were cancer survivors, estrogen supplementation was not an option, even though their levels of estrogen were low.

It's likely, Barton and her colleagues conclude, that a woman must have adequate levels of estrogen in order for testosterone to be an effective treatment for low libido.

In an editorial accompanying the study, Drs. Patricia A. Ganz and Gail A. Greendale of the University of California, Los Angeles say addressing low sex drive in female cancer survivors "must take a comprehensive approach," and should address body image, mental health and partner relationship.

SOURCE: Journal of the National Cancer Institute, May 2, 2007.

Symptomatic Persian Gulf War Vets Show Brain-Volume Deficits

According to preliminary results from a study probing the possible effects of chemical exposure during the Persian Gulf War, soldiers displaying multiple health-related symptoms upon their return from combat have decreased volume in two brain regions intimately linked to learning and memory.

This morning at the American Academy of Neurology's 59th Annual Meeting in Boston the study's senior investigator, Roberta White, chair of the department of environmental health at the Boston University School of Public Health, revealed early findings based on brain scans and memory tasks administered to 36 veterans.

"This study came out of a bunch of prior studies," says White, who has published multiple evaluations of both the health and cognitive state of Gulf War vets since the early 1990s.

In one study, she noted significant cognitive deficiencies in soldiers exposed to the plume resulting from the destruction of a suspected chemical weapons depot at Khamisiyah in southeastern Iraq in March 1991. Overall, 100,000 soldiers were informed that they might have encountered the nerve agent sarin in the blast. Exposure to the poison can result in loss of control of bodily functions as well as death.

In the current study, White separated Gulf War veterans into two groups—low symptom and high symptom—based on the results of a health evaluation given to them upon return from Iraq at Ft. Devens, in Massachusetts. The average soldier reported five symptoms out of a possible 20, which included forgetfulness, headaches, fatigue, nausea, skin rash and joint pain. Half of the soldiers in the report White presented today returned from the war with more than five of these symptoms; the other half had less than five.

Using magnetic resonance imaging (MRI), White's team determined that soldiers in the high-symptom group consistently evidenced a pair of discrepancies in brain volume: Two regions, their cortex and rostral anterior cingulate gyrus were, on average, 5 percent and 6 percent smaller, respectively. (Both the cortex, the outermost layer of the brain, and the cingulate gyrus, located in the midbrain, are believed to associated with learning and memory.)

In addition, the researchers also administered a memory evaluation called the California Verbal Learning Test—wherein subjects must memorize a list of 16 words and then recall them after time has passed or other lists have been committed to memory. This test registered the vets' ability to acquire and retain information.

In behavioral findings that matched the physical deficits that White had observed in the soldiers brains, the high-symptom group showed some cognitive deficiency, performing, on average, 12 to 15 percent worse on the test than their low-symptom counterparts.

White says that the results revealed a statistically significant correlation between lower brain volume and poor performance on the learning test, adding that these preliminary findings suggest the physical brain discrepancies are likely "a marker for some kind of underlying central nervous system difference between high- and low-symptom groups."

Going forward, she plans to factor in the kind and amount of potentially harmful substances the soldiers were exposed to—chemicals ranging from pesticides to nerve agents, like sarin. Adding exposure into the equation, she says, "gets us much … closer to some kind of change or an effect of some kind of exposure in the Gulf."

As to whether these symptoms are part of a pathology known as "Gulf War syndrome," an illness that has been linked to immune system disruptions in troops who had served in the Gulf War, White says she cannot be sure. "I have never been able, in 16 years of research, to identify a common core group of symptoms that could be characterized as Gulf War syndrome."

Source : http://www.sciam.com

Pistachios May Take Bite Out of Cholesterol

Pistachios could help lower cholesterol, according to an industry-funded study presented Monday at the Experimental Biology meeting in Washington, D.C.

"Pistachio amounts of 1.5 ounces and three ounces (per day) -- one to two handfuls -- reduced risk for cardiovascular disease by significantly reducing LDL ("bad") cholesterol levels, and the higher dose significantly reducing lipoprotein ratios," study author Sarah K. Gebauer, a graduate student in integrative biosciences at Penn State, said in a prepared statement.
The multi-week study, which received funding from the California Pistachio Commission , concluded that three ounces of pistachios a day reduced LDL levels by 11.6 percent, total cholesterol levels by 8.4 percent, and non-high density lipoproteins (non-HDL) by 11.2 percent. Levels of non-HDL are considered reliable predictors of cardiovascular disease (CVD) risk.

The researchers also said that a handful of pistachios provide the same antioxidants found in dark, leafy vegetables and brightly-colored fruit.

"Our study has shown that pistachios, eaten with a healthy heart diet, may decrease a person's CVD risk profile," primary investigator Dr. Penny Kris-Etherton, distinguished professor of nutrition at Penn State, said in a prepared statement.

Source : http://www.forbes.com