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Vitamin D: New way to treat heart failure?

Strong bones, a healthy immune system, protection against some types of cancer: Recent studies suggest there’s yet another item for the expanding list of vitamin D benefits. Vitamin D, “the sunshine vitamin,” keeps the heart, the body’s long-distance runner, fit for life’s demands.

University of Michigan pharmacologist Robert U. Simpson, Ph.D., thinks it’s apt to call vitamin D “the heart tranquilizer.”

In studies in rats, Simpson and his team report the first concrete evidence that treatment with activated vitamin D can protect against heart failure. Their results appear online ahead of print in the Journal of Cardiovascular Pharmacology.

In the study, treatments with activated vitamin D prevented heart muscle cells from growing bigger – the condition, called hypertrophy, in which the heart becomes enlarged and overworked in people with heart failure. The treatments prevented heart muscle cells from the over-stimulation and increased contractions associated with the progression of heart failure.

About 5.3 million Americans have heart failure, a progressive, disabling condition in which the heart becomes enlarged as it is forced to work harder and harder, making it a challenge even to perform normal daily activities. Many people with heart disease or poorly controlled high blood pressure go on to experience a form of heart failure called congestive heart failure, in which the heart’s inability to pump blood around the body causes weakness and fluid build-up in lungs and limbs. Many people with heart failure, who tend to be older, have been found to be deficient in vitamin D.

“Heart failure will progress despite the best medications,” says Simpson, a professor of pharmacology at the U-M Medical School. “We think vitamin D retards that progression and protects the heart.”

The U-M researchers wanted to show whether a form of vitamin D could have beneficial effects on hearts that have developed or are at risk of developing heart failure. They used a breed of laboratory rats predisposed to develop human-like heart failure.

The researchers measured the effects of activated vitamin D (1,25 dihydroxyvitamin D3, a form called calcitriol) in rats given a normal diet or a high-salt diet, compared to control group rats given either of the same two diets, but no vitamin D treatment. The rats on the high-salt diet were likely to develop heart failure within months.

The rats on the high-salt diet, comparable to the fast food that many humans feast on, quickly revealed the difference vitamin D could make.

“From these animals, we have obtained exciting and very important results,” Simpson says.

After 13 weeks, the researchers found that the heart failure-prone rats on the high-salt diet that were given the calcitriol treatment had significantly lower levels of several key indicators of heart failure than the untreated high-salt diet rats in the study. The treated rats had lower heart weight. Also, the left ventricles of the treated rats’ hearts were smaller and their hearts worked less for each beat while blood pressure was maintained, indicating that their heart function did not deteriorate as it did in the untreated rats. Decreased heart weight, meaning that enlargement was not occurring, also showed up in the treated rats fed a normal diet, compared to their untreated counterparts.

Simpson and his colleagues have explored vitamin D’s effects on heart muscle and the cardiovascular system for more than 20 years. In 1987, when Simpson showed the link between vitamin D and heart health, the idea seemed far-fetched and research funding was scarce. Now, a number of studies worldwide attest to the vitamin D-heart health link.

The new heart insights add to the growing awareness that widespread vitamin D deficiency—thought to affect one-third to one-half of U.S. adults middle-aged and older—may be putting people at greater risk of many common diseases. Pharmaceutical companies are developing anti-cancer drugs using vitamin D analogs, which are synthetic compounds that produce vitamin D’s effects. There’s also increasing interest in using vitamin D or its analogs to treat autoimmune disorders.

In more than a dozen types of tissues and cells in the body, activated vitamin D acts as a powerful hormone, regulating expression of essential genes and rapidly activating already expressed enzymes and proteins. In the heart, Simpson’s team has revealed precisely how activated vitamin D connects with specific vitamin D receptors and produces its calming, protective effects. Those results appeared in the February issue of Endocrinology.

Sunlight causes the skin to make activated vitamin D. People also get vitamin D from certain foods and vitamin D supplements. Taking vitamin D supplements and for many people, getting sun exposure in safe ways, are certainly good options for people who want to keep their hearts healthy. But people with heart failure or at risk of heart failure will likely need a drug made of a compound or analog of vitamin D that will more powerfully produce vitamin D’s effects in the heart if they are to see improvement in their symptoms, Simpson says.

Vitamin D analogs already are on the market for some conditions. One present drawback of these compounds is that they tend to increase blood calcium to undesirable levels. Simpson’s lab is conducting studies of a specific analog which may be less toxic, so efforts to develop a vitamin D-based drug to treat heart failure are moving a step closer to initial trials in people.

Source: University of Michigan Health System

1,25-Dihydroxyvitamin-D3 Treatment Reduces Cardiac Hypertrophy and Left Ventricular Diameter in Spontaneously Hypertensive Heart Failure-Prone (cp/+) Rats Independent of Changes in Serum Leptin. Peter Mancuso, PhD; Ayesha Rahman, PhD; Stephen D Hershey, MD; Loredana Dandu, BS; Karl A Nibbelink, MD; Robert U Simpson, PhD. Journal of Cardiovascular Pharmacology. POST COPYEDIT, 15 May 2008. 10.1097/FJC.0b013e3181761906

Josh says:

I’ve always said that taking a multivitamin everyday has to increase your lifespan.

Chinese red yeast rice significantly reduces repeat heart attacks and mortality rates

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 multicenter, randomized, double-blind study, was conducted on almost 5,000 patients, ranging in age from 18-70 over a five-year period at over 60 hospitals in the People’s Republic of China. Corresponding author David M. Capuzzi, M.D., Ph.D, director of the Cardiovascular Disease Prevention Program at Jefferson’s Myrna Brind Center of Integrative Medicine and Zonliang Lu, M.D., Ph.D, from the Fuwai Hospital at the Chinese Academy of Medical Science report their findings in the June 15th edition of the American Journal of Cardiology.

“It’s very exciting because this is a natural product and had very few adverse side effects including no abnormal blood changes,” said Capuzzi. “People in the Far East have been taking Chinese red yeast rice as food for thousands of years, but no one has ever studied it clinically in a double-blind manner with a purified product against a placebo group until now and we are pleased with the results. However, people in the United States should know that the commercially available over-the-counter supplement found in your average health food store is not what was studied here. Those over-the-counter supplements are not regulated, so exact amounts of active ingredient are unknown and their efficacy has not been studied yet.”

The study looked at patients who had suffered a heart attack in the previous year. Study participants were given two-300-milligram XZK capsules or a placebo and tracked over a five-year period. The XZK capsules contained a combination of lovastatin, lovastatin hydroxyl acid, ergosterol and other components.

“I think it is surprising that a natural product like XZK would have this great an effect,” said Capuzzi. “If further testing and study prove true, my hope is that XZK becomes an important therapeutic agent to treat cardiovascular disorders and in the prevention of disease whether someone has had a heart attack or not. But it is important to recognize the fact we do not know exactly how Chinese red yeast rice works. The exact ingredients from the XZK capsules have not been isolated and studied yet. Still the results were so profound, even out performing statins prescribed in numerous western populations, that further study should certainly be investigated.”

Source:  Thomas Jefferson University

Effect of Xuezhikang, an Extract From Red Yeast Chinese Rice, on Coronary Events in a Chinese Population With Previous Myocardial Infarction. Zongliang Lu MD, PhD, Wenrong Kou MD, Baomin Du MD, Yangfend Wu MD, Shuiping Zhao MD, PhD, Osvaldo A. Brusco MD, John M. Morgan MD and David M. Capuzzi MD, PhD. Received 8 June 2007; revised 18 February 2008; accepted 18 February 2008. Available online 11 April 2008.

Kevin says:

Many Westerners dismiss Chinese/Eastern medicine because it is not a replacement for Western medicine. While it can’t replace Western medicine, there is much to be learned and it is great to see large studies like this showing significant results. Chinese medicine also has the benefit of being much, much more affordable to the world’s populations because patents and intellectual property and usually nil.