Vitamin D: A new way to treat heart failure?

In addition to strengthening bones, strengthening the immune system, preventing some cancers, a recent study suggested a new benefit to list the benefits of vitamin D. Vitamin D, also known as ' Sunny 'vitamins, keep the heart - the body's long-distance runner - stay healthy.

Dr. Vitamin U. Simpson, PhD, of the University of Michigan, thinks that vitamin D should be called "cardio".

In the study with mice, Simpson and his research team gave the first concrete evidence that treatment with activated vitamin D can protect the body from heart failure. Their research results are published in the June issue of Cardiovascular Pharmacology magazine. In this study, treating with activated vitamin D prevents cardiac muscle cells from growing bigger - a condition called hypertrophy - makes the heart become larger, more active in people with heart failure. Treatment with vitamin D prevents excessive stimulation and contraction of cardiac muscle cells commonly seen during the development of heart failure.

About 5.3 million Americans suffer from heart failure - a disease that damages active capacity is constantly increasing. The disease causes the heart to grow because the heart is forced to work harder, which makes it even more difficult to function on a daily basis. Many people with hard-to-control heart disease or high blood pressure have a form of heart failure called congestive heart failure, which is a condition in which the heart cannot push blood throughout the body, causing depression, fluid in the lungs and limbs. Most patients with heart failure, often the elderly, lack vitamin D.

Simpson, a professor of pharmacology at UM Medical School, said: 'Heart failure continues to grow despite being treated with the best medicine. We think vitamin D slows down the development of disease and protects the heart . '

Researchers in UM want to know whether vitamin D is beneficial for heart that has developed heart failure or is at risk for heart failure. They used experimental mice to create human heart failure.

Left photo: Cardiac muscle cells in untreated mice show signs of heart failure.Cells are irregular in size and shape, with damaged fibers (purple area).Right: Healthy heart muscle cells in mice treated with calcitriol, vitamin D hormone secreted in the body.(Photo: University of Michigan Health System)

The scientists determined the effect of activated vitamin D (1,25 dihydroxyvitamin D3 called calcitriol) in rats with normal or high salt diets, and compared with the control group of mice also received two meals. The above part but not vitamin D. Mice have high salt diets with heart failure within a few months.

The group of rats with high salt diets, equivalent to fast food that people eat, quickly revealed the difference that vitamin D could produce.

Simpson said: 'From animals, we have obtained important and interesting results'.

After 13 weeks, the researchers found that mice with heart failure in a high-salt diet after being treated with calcitriol significantly reduced some of the basic symptoms of heart failure compared to mice in the same group. High-salt diet but not treated. The heart weight of treated mice also decreased. At the same time, their left ventricles also become smaller, the heart works less with each beat. While blood pressure remains the same, this indicates that their heart function is not impaired like untreated mice. The reduced heart weight, which means that the bulge does not occur, also occurs in treated mice with normal diets compared to those in the untreated group.

Simpson and colleagues studied the effects of vitamin D on heart muscle and cardiovascular system for more than 20 years. In 1987, when Simpson pointed out the link between vitamin D and heart health, that idea seemed difficult to achieve while funding was scarce. So far, there are many studies worldwide that validate this relationship (see quote below). The new understanding further raises concerns about widespread vitamin D deficiency - affecting up to one-third to half of the population of middle-aged or older Americans - increasing the risk Many types of diseases in humans. Pharmaceutical companies are developing anti-cancer drugs that use substances similar to vitamin D, a synthetic compound that produces the effects of vitamin D. Concerns about using vitamin D or similar substances to Treatment of immune disorders is also increasing.

In more than a dozen types of tissues and cells in the body, activated vitamin D acts as a powerful hormone, regulating the expression of essential genes and quickly activating enzymes and proteins. For the cardiovascular system, Simpson's team has revealed exactly how activated vitamin D binds to vitamin D receptors, creating a calming and protective effect. The research results are published in the February issue of Endocrinology.

Sunlight stimulates skin to produce activated vitamin D. People can absorb vitamin D from certain foods and vitamin D supplements. Taking a vitamin D supplement and sunbathing in a safe way are suitable for those who want to keep their heart healthy. . For people who have had heart failure or are at risk for heart failure, they need to use a vitamin D compound if they want to relieve symptoms. Simpson said the drugs would make vitamin D more effective for the heart.

Alternative compounds for vitamin D are already on the market. Their drawbacks are the effects of increasing the amount of calcium in the blood to an undesirable level. Simpson's lab is working on a less toxic compound. Efforts to develop a vitamin D-based drug to treat heart failure are taking a step closer to the first human test.

In addition to Simpson, UM authors participating in the study included Dr. Peter Mancuso (UM environmental health department), Lorendana Dandu and Karl A. Nibbelink (pharmacy department at UM medical school). The research was funded by the National Council for Health. Patents related to this study have been registered by UM Technology Transfer Office.