One Drink Of Red Wine Or Alcohol Is Relaxing To Circulation, But Two Drinks Are Stressful

Daily Science Journal (Feb. 13, 2008) — One drink of either red wine or alcohol slightly benefits the heart and blood vessels, but the positive effects on specific biological markers disappear with two drinks, say researchers at the Peter Munk Cardiac Centre of the Toronto General Hospital.

Researchers conducted a real-time study of thirteen volunteers to determine whether a red wine with a verified high polyphenol content differs from alcohol in its effects on specific markers associated with a greater risk of high blood pressure, coronary artery disease and heart failure.

A large number of population studies have shown a protective effect of light or moderate alcohol drinking against the risk of death and the development of heart disease. Many studies have also reported specific benefits of red wine.

Population surveys found lower rates of heart disease, despite high-fat diets, in some European countries where red wine was consumed regularly. Widely known at the French paradox, this has created a huge interest in exploring if and how red wine has a protective effect against heart disease.

However, the findings of this study* showed virtually identical effects of red wine and alcohol on the specific markers tested. After one drink of either red wine or alcohol, blood vessels were more “relaxed” or dilated, which reduced the amount of work the heart had to do. But, after two drinks, the heart rate, amount of blood pumped out of the heart, and action of the sympathetic nervous system all increased. At the same time, the ability of the blood vessels to expand in response to an increase in blood flow diminished. This counteracted the beneficial effect of one drink of red wine or alcohol.

“We had anticipated that many of the effects of one ethanol drink would be enhanced by red wine. What was most surprising was how similar the effects were of red wine and ethanol. Any benefits that we found were not specific to red wine,” said Dr. John Floras, Director of Cardiology Research at the Peter Munk Cardiac Centre, and at Mount Sinai Hospital, in whose laboratory the study was performed. However, Dr. Floras cautioned this study measured the effects of these drinks on one occasion only. The effects of daily wine or alcohol intake may be quite different.

The laboratory of Dr. Floras, who holds the Canada Research Chair in Integrative Cardiovascular Biology and is a Professor of Medicine at the University of Toronto, and a Career Investigator of the Heart and Stroke Foundation, is one of the few in the world equipped to measure simultaneously a broad spectrum of factors such as blood pressure, heart rate, sympathetic nerve firing and arterial diameter.

Healthy, non-smoking adults who were not heavy drinkers or total alcohol abstainers were studied. Participants attended three separate morning sessions during which “standard” drinks of red wine, ethanol or water were administered at random, single-blind, two weeks apart. A 4-oz glass of wine (120 ml), and a 1.5-oz (44 ml) shot of spirits is considered to be one standard drink. All blood alcohol levels alcoholic were below .08, the legal limit for drivers.

The Quality Assurance Laboratory of the Liquor Control Board of Ontario selected a moderately priced pinot noir with a verified high t-resveratrol content, a polyphenol compound found in plants, including red grapes, which exhibits antioxidant properties. Alcohol or substances in alcohol such as resveratrol may improve blood vessel function and also prevent platelets in the blood from sticking together, which may reduce clot formation and the risk of heart attack or stroke.

Select study findings:

One drink of either red wine or alcohol:

* Has no effect on heart rate, blood pressure or sympathetic nerve activity, which activates the “fight or flight” reaction and generally modulates heart rate and sets the diameter of blood vessels in order to redistribute blood;
* Dilates the brachial artery.

Two drinks of either alcohol or red wine:

* Increase sympathetic nerve activity, heart rate, and the amount of blood the heart pumps out, and also blunt the ability of the brachial artery to expand further in response to blood flow.
* Increases in heart rate and sympathetic nerve activity are recognized markers for hypertension (high blood pressure), heart failure and sudden death.

“Our findings point to a slight beneficial effect of one drink – be it alcohol or red wine – on the heart and blood vessels, whereas two or more drinks would seem to turn on systems that stress the circulation. If these actions are repeated frequently because of high alcohol consumption these effects may expose individuals to a higher risk of heart attacks, stroke or chronic high blood pressure,” noted Dr. Floras, adding that the American Heart Association (AHA) does not recommend that anyone start drinking alcohol to prevent heart disease. Reducing risk can be done using other methods such as exercise and following a healthy diet.

The study entitled “Dose-related effects of red wine and alcohol on hemodynamics, sympathetic nerve activity, and arterial diameter”, was published in the February edition of the American Journal of Physiology, Heart and Circulatory Physiology. This study was supported by the Heart and Stroke Foundation of Ontario, the Canadian Institutes of Health Research, and the Canada Research Chairs Program.

Adapted from materials provided by University Health Network, via Newswise.

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'Weight Training' Reduces Fat And Improve Metabolism In Mice

Daily Science Journal (Feb. 8, 2008) — Researchers from the Boston University School of Medicine (BUSM) have demonstrated that in mice, the use of barbells may be as important to losing weight and improving health as the use of running shoes. The discovery builds upon the fact that skeletal muscle consists of two types of fibers. Endurance training such as running increases the amount of type I muscle fibers, while resistance training such as weightlifting increases type II muscle fibers. Using a mouse genetic model, BUSM researchers demonstrated that an increase in type II muscle mass can reduce body fat which in turn reduces overall body mass and improves metabolic parameters such as insulin resistance. These studies indicate that weight bearing exercise, in addition to endurance training, may benefit overweight people.

Weight-lifting. "We've shown that type II muscle does more than allow you to pick up heavy objects," said Kenneth Walsh of Boston University School of Medicine. "It is also important in controlling whole-body metabolism." (Credit: iStockphoto/Sean Locke)

Researchers used a genetic trick in obese mice that caused the mice's muscles to bulk up as though they had been lifting weights. The researchers found that the "genetically reprogrammed" mice lost fat and showed other signs of metabolic improvement throughout the body. What's more, those benefits were seen even though the mice continued eating a diet high in both fat and sugar and didn't increase their physical activity at all.

The researchers genetically engineered a mouse, called the MyoMouse, to grow type II fibers by activating a muscle growth-regulating gene. The gene, called Akt1, was engineered in such a way that it could be turned on and off at will by researchers. Even without exercise, activating the gene made the MyoMouse physically stronger. When the gene was de-activated, the mouse returned to its original strength. While stronger and faster than a regular mouse, the MyoMouse did not run with as much endurance on a treadmill, a finding that is consistent with the growth of type II rather than type I muscle. These findings demonstrate that the mouse was genetically programmed to have the characteristics of a lean and powerful sprinter rather than those of a gaunt marathon runner.

"We've shown that type II muscle does more than allow you to pick up heavy objects," said Kenneth Walsh of Boston University School of Medicine. "It is also important in controlling whole-body metabolism."

In the study, the Akt1 gene was turned off and the MyoMice were fed a high fat/high sugar diet with a similar caloric composition as a meal from a fast food restaurant. Over an eight-week period, the mice became obese and insulin resistant and developed fatty acid deposits in their liver, a condition referred to as hepatic steatosis or fatty liver disease.

The researchers then activated the Akt1 gene in the animals which led to the growth of type II muscle fibers. "Remarkably, type II muscle growth was associated with an overall reduction in body mass, due to a large decrease in fat mass. In addition, blood tests showed that these mice became metabolically normal and their fatty liver disease rapidly resolved," said senior author Kenneth Walsh, PhD, a professor of medicine and head of Molecular Cardiology at the Whitaker Cardiovascular Institute at BUSM.

The beneficial changes occurred despite the fact that the mice continued to eat the same high-calorie diet and did not display any increase in physical activity. "This work shows that type II muscle just doesn't allow you to pick up heavy objects, it is also important in controlling whole body metabolism," added Walsh.

Further analysis found that the mice burned fat because of changes in the physiology and gene expression of their fat and liver cells. "Thus, it appears that the increase in type II muscle fiber orchestrates changes in the body through its ability to communicate with these other tissues," he said.

These findings indicate that type II muscle has a previously unappreciated role in regulating whole body metabolism through its ability to alter the metabolic properties of remote tissues. These data also suggest that strength training, in addition to the widely-prescribed therapy of endurance training, may be of particular benefit to overweight individuals

Finally, these findings may be relevant for understanding aspects of the aging process. "Beyond the age of thirty, humans lose approximately 6 lbs of muscle mass per decade. Surprisingly, aging individuals predominantly lose type II muscle. Thus a 50 year old may be relatively good at playing tennis or jogging because type I muscle is preserved, but a measurement of grip strength or core body strength could show appreciable declines," explained Walsh. Therefore, this new study suggests that the loss of type II muscle contributes to the development of obesity and diabetes as we age.

The BUSM researchers suspect that the beneficial effects of muscle growth seen in the MyoMouse are mediated through the production and secretion of a variety of signaling factors. Walsh and his colleagues are currently identifying the novel proteins in muscle that communicate with other tissues. These new proteins, referred to as "myokines" from the Greek words "muscle" and "motion," may represent new targets for therapies that mimic the benefits of weight training for the treatment of obesity and diabetes as well as muscle wasting disorders.

"The work of [Walsh and his colleagues] reveals the intricate interplay between diet, energy balance, and the function/morphology of diverse tissue systems such as skeletal muscle and liver," said Brooke Harrison and Leslie Leinwand of the University of Colorado at Boulder in a commentary in the journal Cell Metabolism. "These findings indicate that interventions designed to increase skeletal muscle mass in at-risk human populations may prove to be critical weapons in the fight against obesity and obesity-related comorbidities including diabetes, heart disease, stroke, hypertension, and cancer."

The study appears in the February 6th issue of Cell Metabolism. The researchers include Yasuhiro Izumiya, Teresa Hopkins, Carl Morris, Kaori Sato, Ling Zeng, Jason Viereck, James A. Hamilton, Noriyuki Ouchi, Nathan K. LeBrasseur, and Kenneth Walsh, of Boston University School of Medicine, Boston, MA.

Adapted from materials provided by Boston University, via EurekAlert!, a service of AAAS.

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Theory Of Facial Aging Gets A Facelift

Daily Science Journal (Aug. 9, 2007) — The longstanding idea that the entire human face ages uniformly is in need of a facelift, say researchers at UT Southwestern Medical Center who have found that multiple, distinct compartments of fat in the face age at different rates.

Drs. Rod Rohrich (right) and Joel Pessa have discovered that the human face is made up of individual fat compartments that gain and lose fat at different times and different rates as people age. Facial aging is, in part, characterized by how these separate compartments change as we grow older. (Credit: UT Southwestern Medical Center)

The findings, published in a recent issue of Plastic and Reconstructive Surgery, challenge previously held theories regarding aging and may offer new ways to help turn back the clock, UT Southwestern plastic surgeons say.

"For hundreds of years, everyone has believed that the fat on the face is one confluent mass, which eventually gets weighed down by gravity, creating sagging skin," said Dr. Joel Pessa, assistant professor of plastic surgery and the study's lead author. "In our studies, however, we were surprised to find that this is not the case; the face is made up of individual fat compartments that gain and lose fat at different times and different rates as we age."

The study involved injecting different types of dye into facial cavities of 30 cadavers. Despite at least 24 hours of settling time, the dye, rather than permeating the entire face, stayed in separate areas -- showing that individual facial compartments have boundaries between them that act like fences. These fences, which seem to be composed of fibrous tissue, allow the face to maintain its blood supply should it become injured.

Dr. Pessa said the face resembles a three-dimensional puzzle, with fat divided into distinct units around the forehead, eyes, cheeks and mouth. Facial aging is, in part, characterized by how these separate compartments change as we grow older.

A youthful face is characterized by a smooth transition between these compartments. As people age, contour changes occur between these regions due to volume losses and gains as well as repositioning of the compartments. Eventually, this can result in sagging or hollowed skin and wrinkles.

"This is a revolutionary way of viewing facial anatomy. It not only tells us how we age, it shows us why we age the way we do, and why every part of the face, from the eyelids to the cheeks, ages differently," said Dr. Rod Rohrich, chairman of plastic surgery and senior author of the study. "This will help plastic surgeons around the world not only understand how we can better rejuvenate the face, but how people age as a physiological process."

This breakthrough could have tremendous implications in helping plastic surgeons target facial "trouble" areas and use injectible fillers to add volume to individual sections of the face. It could also aid in developing new and improved cosmetic and reconstructive surgery techniques, Dr. Rohrich said.

"Understanding how fat is compartmentalized will allow us to be very accurate and precise in how we approach facial rejuvenation," Dr. Pessa said. "This gives us an algorithm, or scientific approach, to help ascertain what areas of the face may need extra fat to combat the aging process. It also is a major breakthrough in facial anatomy that will have major implications for future studies on aging and possibly hold clues to the study of other diseases such as obesity, diabetes and cancer."

Adapted from materials provided by UT Southwestern Medical Center, via EurekAlert!, a service of AAAS.

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