Animal Toxin: Hidden Cures

 
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They slither... Snakes

The Danger:
Snakes bites can range from being considered relatively harmless (with the exception of punctured skin), like that of the common garden snake1 , to bites that lead to immediate death with a minimum amount of venom, such as that of the King Cobra. Similarly, snake toxins have some of the most diverse mechanisms of disrupting human physiology. For the most part, the toxins produced area mix of “proteinaceous” and “non-proteinaceous”  components with the “proteinaceous” components usually compromising enzymes and other polypeptides that are essential to an organism’s function and  structure.  The chemical toxins’ mechanisms of action range from disrupting the nervous system, to cardiotoxins, to myotoxins, to increasing or decreasing coagulative functions, to merely causing an inflammation and numbing the area affected (11).
Snake venom, according to the species that produces it, has the ability to behave as a procoagulant or anticoagulant. The toxin has the ability to activate coagulation factors (i.e. Factors X, V,) in the blood system that will start the clotting reaction in the circulatory system.  The release of or von Willebrand  factor initiates am increase of plaquets in the organism facilitating coagulation. Likewise, toxins can force normal proteins to change from a non-functional stage (protrombine) to one that promotes coagulation (trombine). Examples of snakes producing coagulant toxins are Vipera russellii, Notechis scutatus,and Bothrops sp. Usually, these coagulant toxins are also accompanied by the addition of other toxic components such as neurotoxins, myotoxins, etc.(1)

Anticoagulantes behave in a complimentary manner. They too activate proteins that promote “clot dissolution,” such as Plasminogens, to a degree that no blood clot can begin to form. They may directly attack the ability of plaquette aggregation, or disrupt the phospholipids of plaquettes’ membrane. They also work as inhibitors to the naturally occurring coagulation mechanism frustrating an organism’s attempt to stop the blood flow. Examples of species that present anticoagulant abilities are Bitis nasicorni, Crotalus terrificus terrificusI,and Bothrops insularis.(1)
Neuromuscular blockage (due to neurotoxins) is another effect of snake venom and is due to the myotoxins. These toxins can work in two ways. The first pathway has the toxin act as a competitor in acetylcholine receptor and irreversibly bind to its active site. The second mechanism of action is the use of toxins that disrupt the release of acetylcholine and other transmitters by simply disrupting the mechanisms that allow for the exocytosis of vesicles containing the transmitters. Both pathways will cause paralysis, disrupting the organism’s motility. The Bungarus multicinctus contains a mixture of toxins that work in both these ways. (11)
Neurotoxins in general, such as that found in King Cobra venom, produce the death of cells, especially those important to the nervous system which  governs an organism’s physiological functions. The effects of these neurtoxins can induce myonecrosis (11).

Cobra

Ophiophagus hannah-- Courtesy of Wikipedia

Nature’s twist
Although the procoagulant and anticoagulant toxins maybe an effective way to disrupt an organism’s physiology. In small quantities, the compounds found in these toxins can be used to correct clotting problems in humans, especially the anticoagulant compounds. Fibrolase is a toxin compound isolated from a copperhead snake. It has anticoagulant properties that have “direct action” on the clotting proteins in a human hence helping to eliminate clots in thrombosis. In fact, the anticoagulant toxin has been tested in dogs to treat thrombosis by eliminating thrombus in a carotid artery(13).
Hannalgesin, a toxin king cobras produce, is a neurotoxin that can be used as an analgesic in small quantities36 in 11 without disrupting neurological or muscular functions. Furthermore, the same toxin enabled research to investigate mechanisms blocking the anesthetic effect which can be used to study both the antidote for the toxin itself and the participation of other factors in anti-nociceptive pathways in organism. (11)
Neurotoxins have also been found to have therapeutic properties for autoimmune diseases, such as HIV, by acting as the virus’ innocuous competitor for the CD4 and CD8 receptors. The compound stops the pathogen from infecting the cell by preventing its attachment to the host cell. (13)
All citation numbers are referenced in "Works Cited" Page
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