The leech has recently confirmed its biomedical interest for scientists by showing that it contains an extensive list of new potential molecules that may become useful tools in the treatment of cardiovascular diseases.
The details of this research appear in the October issue of Molecular and Cellular Proteomics, an American Society for Biochemistry and Molecular Biology journal.
Scientists have increasingly turned to blood-feeding invertebrates as a source for drugs and lead compounds to treat cardiovascular disease because these animals have evolved highly efficient mechanisms to feed on their hosts by blocking blood coagulation.
"Most heart attacks and strokes are associated with a blocked artery," explains study author Oscar Yanes. "In some cases, blood clots may cause the blockage of arteries that lead to cardiovascular disease. People with cardiovascular disease typically have an increased tendency to form blood clots, and a decreased ability to dissolve clots before they can do any damage. Therefore, compounds interrupting the blood coagulation cascade may inhibit thrombus development."
Using a strategy dubbed "Intensity Fading MALDI MS," Yanes and his colleagues at the Universitat Autònoma de Barcelona analyzed peptides and small proteins in the saliva of the medical leech Hirudo medicinalis for their ability to bind to molecules called serine proteases. This is a fast and extremely sensitive mass spectrometry-based analytical approach. Most of the coagulation factors involved in blood coagulation cascade are enzymes that belong to the serine protease family. Thus molecules that can bind to and block the action of such serine proteases can prevent coagulation.
Of the nearly 2,000 molecules the researches screened, more than 75 of them interacted specifically with the serine protease used throughout the work as target molecule. Sixteen of these binding molecules were isolated and subsequently characterized as new inhibitors that had potential to be used as drugs in treating cardiovascular disease.