New biological products
Alexey Levin, Voice of America
Bioweapons of streptococciResearchers from the USA, Great Britain and Israel believe that they have managed to identify the main factor of the pathogenic effect of one of the varieties of streptococcal bacteria on the human body.
Group A streptococci cause many diseases – from mild lesions of the throat and skin to deadly pathologies. These include diseases such as rheumatic heart disease and necrotizing fasciitis, purulent melting of soft tissues.
Scientists have long known that these microbes seriously weaken the immune system, but they were not sure exactly how this happens. Professor of pharmacology and pediatrics at the University of California Victor Nizet and his colleagues believe that they have managed to solve this mystery. They came to the conclusion that these bacilli reduce the activity of the immune defense of the infected organism with the help of the enzyme SpyCEP, which they produce in large quantities.
This substance belongs to the family of proteolytic enzymes that catalyze protein cleavage reactions. The researchers found that SpyCEP extremely strongly suppresses the activity of interleukin-8. This biologically active peptide plays a primary role in the mobilization of white blood cells from the neutrophil family, which absorb and destroy bacteria that have entered the body. The weakening of its work allows microbes to multiply at an increased rate.
The discovery of scientists from the Nizet group indicates the possibility of combating streptococcal infections with drugs that can prevent the release of the enzyme SpyCEP or block its action.
Yeast analgesicsAmerican scientists have turned yeast cells into biofactories for the production of alkaloids.
Chemists at the California Institute of Technology Christina Smolke and Kristy Hawkins have integrated three plant genes borrowed from opium poppy, yellow basilisk and rhesus Tal into the hereditary apparatus of yeast cells.
The added genes encode the structure of enzymes that catalyze the biosynthesis of alkaloids from the benzylisoquinoline family, which includes painkillers such as papaverine, codeine and morphine. The experimenters also provided yeast cells with the gene of the human enzyme P450, which affects the rate of reactions affecting alkaloid molecules.
Yeast cells with a modified hereditary apparatus began to produce significant amounts of seven different benzylisoquinolines. Already, the productivity of such crops ranges from 100 to 200 milligrams per liter, but their creators believe that it can be increased tenfold.
Of course, morphine and papaverine can be obtained in other ways. However, there is every reason to hope that other combinations of genes can be embedded in yeast cells, which will force them to synthesize other valuable alkaloids that have not yet been produced by industrial methods. So the technique of Pasadena chemists most likely has a great future.
Artificial heparinThe oldest technological university in America has developed a method for producing synthetic heparin.
Heparin is a biologically active substance from the family of polysaccharides that prevents blood clotting. For this reason, it is widely used in medicine for the prevention and treatment of thrombosis, blockage of blood vessels by blood clots. Currently, over half a billion doses of this drug are used worldwide every year.
In the mammalian body, heparin is produced by mast cells, which are mainly concentrated in the tissues of the inner lining of blood vessels, as well as in the lungs and liver. The medical industry manufactures heparin from the liver and lung tissues of cows and other cattle.
However, they sometimes carry biological contamination, which is not always possible to detect by factory control methods. For example, this spring a scandal broke out in the United States caused by reports of substandard Chinese-made heparin, which caused at least two dozen deaths. It is not surprising that chemists have been looking for ways of industrial synthesis of this anticoagulant for a long time.
Now researchers at Rensselaer Polytechnic Institute in New York State, working with colleagues from other research centers, have reported that they have made significant progress towards achieving this goal. The technology they have developed makes it possible to produce milligram quantities of ideal pure heparin. Of course, this figure looks very modest compared to the total global production of heparin, which now exceeds 30 tons.
However, the whole point is that the previous methods of heparin synthesis did not go beyond nanograms. Professor of biocatalysis and metabolic technologies Robert Lindhardt, who heads this project, is confident that in the near future his team will reach the kilogram milestone and that the pharmaceutical industry will be able to start mass production of synthetic heparin in five years.
Treatment of hypertension and Alzheimer's diseaseAmerican scientists have come to the conclusion that newly created drugs used to normalize blood pressure not only contribute to the prevention of Alzheimer's disease, but even slow down its course.
Researchers at Boston University have identified an unexpected link between Alzheimer's disease and drugs from the ARB family. This reduction is now well known to many people suffering from arterial hypertension. It stands for: blockers of tissue receptors to angiotensin II. All these drugs neutralize the protein-like substance angiotensin II, which causes narrowing of blood vessels and thereby increases blood pressure. Angiotensin II also stimulates the secretion of the hormones vasopressin and aldosterone, which again contribute to the increase in pressure.
The first representative of the drugs from the ARB group, losartan, was synthesized in the middle of the last decade. Since then, more effective drugs of similar action have appeared, for example, irbesartan and telmisartan. These drugs are considered a very promising weapon of medicine in the fight against hypertension.
And now Professor of pharmacology Benjamin Wolozin and his colleagues have revealed a very unexpected additional effect of BRA drugs. They subjected to statistical processing the health information of more than five million former servicemen stored in state data banks. This analysis showed that long-term use of angiotensin II receptor blockers reduces the risk of developing Alzheimer's disease and other forms of age-related dementia by 35-40%.
Scientists have also found that these drugs slow down the process of memory weakening and decreased intelligence after the onset of this disease. The reason for this effect of antihypertensive drugs from the ARB group has yet to be determined. Boston researchers made their presentation at the 11th International Conference on Alzheimer's Disease and Related Disorders, held in late July in Chicago.
Portal "Eternal youth" http://www.vechnayamolodost.ru07.10.2008