The new Viagra effect
Viagra prevented bowel cancer in mice
Ksenia Malysheva, Naked Science
Sildenafil, better known as Viagra, is a drug with a complicated history. It was developed as a cure for coronary heart disease and angina pectoris, but it turned out that it has little effect on blood flow in the heart area, but it increases blood flow to the pelvic organs, which determined its further use as a remedy for erectile dysfunction. However, sildenafil is indicated for women and children with pulmonary hypertension. And this year, scientists from the Medical College at the University of Georgia proved that this drug in very small doses is able to prevent the formation of intestinal polyps – outgrowths above the intestinal mucosa. Polyps themselves are not dangerous, but malignant tumors form in them more often than in other tissues.
So far, the drug has been tested only on genetically modified mice (microdoses of sildenafil were added to drinking water). A mutation introduced into the DNA of mice caused their intestines to grow polyps with great speed and frequency; the vast majority of mice developed bowel cancer sooner or later. This mutation is also found in humans. Viagra halved the likelihood of polyps in mice. The next step is testing on people at risk: those who had close relatives suffering from bowel cancer, who previously had intestinal polyps, and people suffering from chronic diseases of the digestive tract, such as colitis. We wrote about the survival calculator for bowel cancer earlier.
The stimulating effect of viagra, familiar to everyone, is associated with the drug's ability to relax the smooth muscles of blood vessels, allowing blood to fill the cavernous bodies of the penis. However, the drug has another effect: it stimulates the synthesis of cyclic guanosine monophosphate, an important component of the membranes of epithelial cells lining the intestine from the inside. The exact mechanism of action of sildenafil is unknown, however, the authors of an article published in Cancer Prevention Research note that an increased concentration of cyclic guanosine monophosphate suppresses excessively active division of epithelial cells; moreover, with an excess of this substance, the body gets rid of mutant cells more easily with the help of apoptosis – the process of controlled cell death.
Sildenafil does not help to get rid of already formed polyps, the authors of the study note, therefore its potential is to prevent the disease in people at risk, not treatment.
There is another well–known drug that increases the level of cyclic guanosine monophosphate in cells - this is linaclotide, a drug for the treatment of chronic constipation and irritable bowel syndrome. It also proved effective against the formation of new polyps, but in any, even very small, dosages it causes diarrhea; small doses of viagra have not yet shown any side effects.
Another study was published in July the same group of authors, which described the effect of viagra on the formation of polyps in GM mice suffering from chronic colitis; in this case, the drug was less effective, but also reduced the number of polyps and also partially relieved inflammation. About 5% of all cases of cancer of the rectum and colon are explained by chronic inflammation, 80% – the spontaneous emergence of a non-stop dividing group of cells. Statistical studies link bowel cancer with the use of processed foods with a large amount of dietary supplements (although if you carefully analyze the data obtained, it turns out that these fears are greatly exaggerated – VM).
Portal "Eternal youth" http://vechnayamolodost.ru