Sunday, November 13, 2011

New drugs to significantly decrease heart attacks

Several pharmaceutical companies are betting on a gene that, when its transcription is inhibited, increases the filtering of cholesterol by the liver. Less cholesterol means less chance of atherosclerosis, in which fatty deposits can lead to blocking of coronary arteries, resulting in a heart attack. Therefore, it is seen as a big opportunity in medicine, especially because heart attacks caused by building up fat in artery walls are increasing in frequency because of our eating habits. It will, however, still take years to develop a working drug for use in human patients.

Big pharmaceutical companies such as Sanofi, Pfizer and Agmen are attempting to develop a drug that inhibits the cholesterol gene, called PCSK9. Its biological effect was found in people carrying a mutation, which causes dysfunction of the gene. These people, a small percentage of the population, were found to have a significant decrease in the incidence of heart attack. Interestingly, there is a big difference between black and white people. Black people were found to have a decreased risk of 88 percent, compared to people with a functional PCSK9 gene, while white people only found their risk decreased by 47 percent. Nevertheless, if you would be able to prevent half of the world's heart attacks, that could save the lives of millions.

PCSK9 codes for an enzyme that is involved with cholesterol homoeostasis. That means it is part of a system that is meant to keep a balance in the body's cholesterol. Specifically, PCSK9 targets the LDL receptor, that is involved with uptake of LDL, which is a bad form of cholesterol. Because LDL can't bind to its receptor anymore, breakdown of the bad cholesterol is decreased, which results in increased LDL, that is free to roam in the body, and can attach to vascular walls where it can cause harm by obstructing the vessels.

In our society, many people suffer from too high levels of cholesterol. That is not because of an overactive PCSK9 gene, but because people eat too much fatty foods. Improving our eating habits would be the best way to prevent a heart attack caused by obstructed vessels in atherosclerosis, but a lot of people can't find an incentive for change. For pharmaceutical companies, finding drugs that help solve the problem means a guarantee for billions of profits, hence why many companies seek to develop a drug that is based on PCSK9 inhibition. It is also interesting to note that having no functional PCSK9 at all seems not to cause any side-effects in the body, as was concluded from observing people with a mutation in both copies of their genes.

In addition to genes involved with PCSK9 metabolism, chocolate consumption can also play a role in preventing cardiovascular disease. That is probably something most people with high cholesterol would love to know.

No comments:

Post a Comment