Editorial [Hot Topic: Pharmacological Impact of Snake Venom Compounds (Executive Editor: C. Marcinkiewicz)]

The snake venoms are the natural sources of many compounds that fascinated people through the history of pharmacology. Thus, the major part of logos of many national pharmaceutical organizations contains the image of a snake. Current drug design research considers venoms of many snakes as a valuable source for identification of new compounds with potential application in the pharmacology of many diseases. Moreover, toxic and non toxic components of snake venoms are very useful reagents for conducting medical research and understanding the physiology and pathology of many processes occurring in the body. Good examples are the snake venom disintegrins that inspired researchers to discover and characterize mammalian ADAM family proteins. The same snake venom disintegrins became a paradigm for the synthesis of new anti-platelet peptides and peptidomimetics that are currently used as therapy for certain heart and cardiovascular diseases. In this issue authors will describe the current stage and the future of research related to the compounds isolated from snake venoms. Among the many others, these compounds include for example anti-adhesive proteins such as disintegrins; enzymes such as phospholipases, metalloproteinases or serine proteases; and many neurotoxins affecting the central and peripheral nervous system. They are utilized in the pharmaceutical research of many diseases including blood coagulation, vasculature, nervous system, cancer, inflammatory diseases. The first two review papers of this issue are devoted to snake venom disintegrins, in the context of their application in angiogenesis research. The first review [1] summarizes current knowledge about disintegrins that inhibit α1β1 integrin. This integrin is highly expressed on all types of microvascular endothelial cells and its participation in the neovascularization process has been established. The authors discuss structure-function correlation of the novel group of snake venom disintegrins that contain KTS or RTS motifs in their integrin-binding loop. These disintegrins are currently in the laboratory trials as a therapeutic approach toward inhibition of tumor vascularization. Swenson and his colleagues [2] focused their review on the characterization of the effect of RGD-containing disintegrins on angiogenesis in various cancer models such as breast, ovarian and prostate. The RGD-disintegrins are the most investigated snake venom proteins, and in the past based on their structure two drugs, triofiban and eptifibatide were introduced for the therapy of certain cardiovascular diseases. The major interest of the authors is the homodimeric disintegrin contortrostatin and its inhibitory effect on the αvβ3 integrin present on endothelial cells. This recombinant disintegrin in a monomeric form appears to be a promising compound, and is an alternative to conventional anti-angiogenic agents. The majority of viper venoms work on the prey by affecting blood coagulation and the vascular system. Many laboratories focused on these properties of venoms and isolated several compounds that are useful in pharmaceutical research related to these systems. The next two articles will characterize these compounds. Yamazaki and Morita [3] described a variety of toxins present in viper venoms that have unique biological activities that are not seen in mammals. These toxins affect platelet aggregation, blood coagulation cascade and vascular endothelial cells and have potentials in drug design. In this context, the authors also considered toxins from other organism including leeches and ticks. The more oriented review on snake venom agents that affect hemostasis is presented by Clemetson et al. [4]. The aspect of using serine proteases, metalloproteases, C-type lectins, disintegrins and phospholipases is carefully discussed. The authors excellently summarized the effect of these compounds on platelets including investigation of receptor functions and signal transductions. It is interesting that properties of snake venom proteins lead to identification of new platelet receptors such as GPVI. Further studies of these proteins may provide new directions in diagnosis and therapy of human blood diseases......