Lipoic acid could reduce atherosclerosis, weight gain

A new study done with mice has discovered that supplements of lipoic acid can inhibit formation of arterial lesions, lower triglycerides, and reduce blood vessel inflammation and weight gain – all key issues for addressing cardiovascular disease.

Although the results cannot be directly extrapolated beyond the laboratory, researchers report that “they strongly suggest that lipoic acid supplementation may be useful as an inexpensive but effective intervention strategy . . . reducing known risk factors for the development of atherosclerosis and other inflammatory vascular diseases in humans.”

The findings were made by scientists from the Linus Pauling Institute and College of Veterinary Medicine at Oregon State University, and the Department of Medicine at the University of Washington. They were just published in Circulation, a journal of the American Heart Association.

Heart disease is the leading cause of death in the United States.

The study found that lipoic acid supplements reduced atherosclerotic lesion formation in two types of mice that are widely used to study cardiovascular disease, by 55 percent and 40 percent, respectively. The supplements were also associated with almost 40 percent less body weight gain, and lower levels of triglycerides in very low-density lipoproteins.

As a result, the authors concluded that “lipoic acid may be a useful adjunct in the prevention and treatment of atherosclerotic vascular diseases.”

“We are excited about these results, particularly since the supplements of lipoic acid appear to provide several different mechanisms to improve cardiovascular health,” said Balz Frei, professor and director of the Linus Pauling Institute. “They are helping in a fundamental way to reset and normalize metabolic processes, in ways that could help address one of the most significant health problems in the Western world.

“These findings also reinforce the need for more comprehensive human studies,” Frei said. “That will be the next step in our research, in double-blind, randomized, clinical studies during the next five years with Oregon Health and Science University.”

Alpha lipoic acid is a naturally occurring nutrient found at low levels in green leafy vegetables, potatoes and meats, especially organ meats such as kidney, heart or liver. The amounts used in this research would not be obtainable by any normal diet, researchers said, and for human consumption might equate to supplements of about 2,000 milligrams per day. Even at low, normal, dietary levels, the compound can play a key role in energy metabolism.

Atherosclerosis, or what used to be called “hardening of the arteries,” is a long-term process that is now seen as a chronic inflammatory disease, which begins when certain types of white blood cells called monocytes bind to “adhesion molecules” on the walls of arteries. This in turn allows the monocytes to enter the arterial wall, there they become inflammatory macrophages that, in the presence of low density lipoprotein, or LDL, can transform into lipid-laden foam cells – ultimately, an arterial fat deposit.

This chronic process often begins during adolescence, can continue for a lifetime, and has been linked to obesity, poor diet, lack of exercise, diabetes, high blood pressure, genetic predisposition and other causes. The fatty deposits in arteries can ultimately trigger a heart attack or stroke.

Researchers now believe that high levels of alpha lipoic acid can be particularly useful in preventing this process, by inhibiting the formation of the adhesion molecules. It can also lower triglycerides, another important risk factor for cardiovascular disease. It may also function as an antioxidant, and helps to normalize insulin signaling and glucose metabolism.

“From what we understand, this supplement would be most valuable as a preventive mechanism before people have advanced cardiovascular disease,” Frei said. “However, it may help retard the process at any stage, and may also be of value in treating diabetic complications.”

Also of considerable interest, Frei said, is the apparent role of lipoic acid supplementation in reducing weight gain. It appears to have this effect both through appetite suppression, an enhanced metabolic rate, and – at least in laboratory animals – has been shown to stimulate higher levels of physical activity, which again would increase caloric expenditure and further reduce weight.

Mice given lipoic acid supplements simply chose to eat less than a control group that did not receive supplements, suggesting a reduced appetite. In another test, mice that received supplements gained less weight than other mice in a control group that were given identical amounts to eat, suggesting a higher metabolic rate and enhanced activity levels.

Weight gain and obesity is a major risk factor for atherosclerosis and heart disease, and lower weight and abdominal fat may be one of the mechanisms by which lipoic acid has beneficial effects, Frei said. The study concluded that “lipoic acid supplementation may be a promising approach to prevent weight gain and to lower cardiovascular disease risk in humans.”

Although some of the most compelling research with lipoic acid research has been done in mouse models, scientists say, there should be a reasonable extrapolation to humans, because the lipoprotein profile is similar, as well as the composition of the atherosclerotic lesions. These mouse models are routinely used in studies of human atherosclerosis.

Source: Oregon State University

Related stories:

Study finds Chinese food good for your heart
A clinical study on patients who have suffered a heart attack found that a partially purified extract of Chinese red yeast rice, Xuezhikang (XZK), reduced the risk of repeat heart attacks by 45%, revascularization (bypass surgery/angioplasty), cardiovascular mortality and total mortality by one-third and cancer mortality by two-thirds.
The good news in our DNA: Defects you can fix with vitamins and minerals
As the cost of sequencing a single human genome drops rapidly, with one company predicting a price of $100 per person in five years, soon the only reason not to look at your "personal genome" will be fear of what bad news lies in your genes.
UK's organic cows are cream of the crop
A new study by Newcastle University proves that organic farmers who let their cows graze as nature intended are producing better quality milk. The Nafferton Ecological Farming Group study found that grazing cows on organic farms in the UK produce milk which contains significantly higher beneficial fatty acids, antioxidants and vitamins than their conventional ‘high input’ counterparts.
Study identifies trends of vitamin B6 status in US population sample
In an epidemiological study, Tufts University researchers identified trends of vitamin B6 status in a sample of the United States population based on measures of plasma pyridoxal 5'- phosphate (PLP) levels in the bloodstream. Plasma PLP is the indicator used by the federal government to set the current Recommended Dietary Allowance (RDA) of vitamin B6, a nutrient essential for red blood cell function and important for maintaining a healthy immune system and blood glucose levels.
Folic acid, B vitamins not linked to reduced risk of cardiovascular events in high-risk women
Women at high-risk of cardiovascular disease who took a daily supplement of folic acid and vitamin B6 and B12 for seven years did not have an overall reduced rate of cardiovascular events, despite a significant lowering of homocysteine levels, according to a study in the May 7 issue of JAMA.
Vitamin D in brain function
In a definitive critical review, scientists at Children’s Hospital & Research Center Oakland ask whether there is convincing biological or behavioral evidence linking vitamin D deficiency to brain dysfunction. Joyce C. McCann, Ph.D., assistant staff scientist and Bruce N. Ames, Ph.D., senior scientist at Children’s Hospital Oakland Research Institute (CHORI) conclude that there is ample biological evidence to suggest an important role for vitamin D in brain development and function, and that supplementation for groups chronically low in vitamin D is warranted. Their conclusions will be published on April 22, 2008 in the Federation of American Societies for Experimental Biology (FASEB) Journal.
Herbal Science-brand supplements recalled
The U.S. Food and Drug Administration announced the recall of 12 Herbal Science-brand dietary supplements because they might present a health hazard.
Dietary oil may need help in avoiding any side effects of weight loss
An oil made of natural fatty acids that is sometimes used as a weight-loss supplement may need to be paired with hormones or other substances to prevent health problems that can follow rapid weight loss, a new study suggests.

News discussion:

Medicine & Health news