December 18, 2016
Each year, snakebites kill tens of thousands of people, all over the world. Proper first aid is of paramount importance in the life of a snake bite victim, especially in the first hour, also known as the 'golden hour'. Administering the correct antivenom on a timely basis will result in a 100 % chance of survival.Whythen do so many people die from venomous snake bites?The reasons are many.First,the cost of antivenom is pretty high which the common man cannot afford.Second, lack of availability of antivenom in villages. Lastly, multinational drug companies have stopped making antivenom as it is increasingly unprofitable. Also, animal right activists object because the horses suffer.
The first antivenom was introduced, against the Indian spectacled cobra, more than 100 years ago by French Scientist, Albert Calmette, a protégé of Louis Pasteur. He eventually discovered a process by which horses when injected with venom to produce antibodies, whose blood was then extracted and injected in the snake-bitten victim. Today, although much improved over the century, the process remains more or less the same.
Antivenoms can be classified into monovalent (when they are effective against a single species' venom) or polyvalent (when they are effective against a range of species, or several different species at the same time).
The objective of writing this article is to help all Nature loving people to understand the role of venom in modern medicine & how it could save millions of precious lives worldwide.
Even though wrongly misrepresented by Man, reptiles in general and snakes in particular are vital in maintaining the energy balances in terms of predator and prey. The fact of the matter is that 100,000 animals have evolved to produce venom with appropriate glands to house it and the apparatus to expel it; Snakes, scorpions, spiders, a few lizards, bees, sea creatures, octopuses and numerous species of fish.
Today, with cutting edge molecular tools, the scientific community is only beginning to realize the immense potential of snake venom, not only for antivenom but also for cures. Already top medicines for heart disease and diabetes have been derived from snake venom. The potential is such that new treatments for autoimmune diseases, Cancer and pain should be available within a decade. Proteins and toxins within venom can provide key blue prints for treating a wider variety of ailments, including autoimmune disease, stroke and multiple sclerosis.
Importance of Venom
Venom from snake fangs is one of nature’s most efficient prey killers. It consists of a complex cocktail of tissue destroying enzymes with toxic proteins, peptides, short strings of amino acids similar to proteins. The molecules may have different targets and special effects but they work synergistically to either block the auto immune system or paralyze the nervous system or muscle. The end result is the same; the venom has a dilapidating effect on cells and tissue resulting in multi organ failure. Venom can kill by clotting blood and stopping the heart or by preventing clotting and triggering a killer bleed. Dozens, even hundreds of toxins can be delivered in a single bite.
Ironically, the properties that make venom deadly are also what make it so valuable for medicine. Many venom toxins target the same molecules that need to be controlled to treat diseases. These toxins and enzymes target particular molecules fitting into them like keys into locks (most medicines work that way) fitting into and controlling molecular locks to thwart ill effects. We aren’t talking about novel drugs, but entire class of drugs that will directly come from understanding the biochemical nature of venom. So far fewer than a thousand toxins have been screened for medicinal value and a dozen or so major drugs have made it to the market. In reality there could be upwards of 20 million venom toxins waiting to be screened. Toxins from venom and poison sources are also giving a clearer picture of how proteins that control many of the body’s cellular functions work. More importantly, scientists are now manufacturing designer toxins for various therapeutic values. Crystallized venom from snakes is now a medical export from Azerbaijan.
Venom-based Cures
Venom-based cures aren’t a new idea. They show up for example in Sanskrit texts from the second century AD and around 67 BC Mithradates VI of Pontus, an enemy of Rome who dabbed in toxicology was supposedly saved twice on the battle field by Shamans who administered viper venom to his wounds. Cobra venom applied for centuries in traditional Chinese and Indian medicines was introduced to the west in the 1830’s as a homeopathic pain remedy. John Henry Clarke's 'Materia Medica' published around 1900, describes the venom as alleviating many ills, even those caused by venom. Clinical applications of carefully diluted cobra venom include‘Angina pectoris, asthma, Dementia, Hay fever, headache and heart disease.
The science of transforming venom into cures took off in the 1960’s when an English clinician named Hugh Alistair Reid suggested that the venom of the Malayan pit viper might be used against deep vein thrombosis. He had discovered that one of the snake toxins, a protein called 'ANCROD', saps a fibrous protein from the blood, preventing clotting. “Arvin”, a clot busting drug derived from pit viper venom reached clinics in Europe in 1968. The Brazilian pit vipers venom led to the development in the 1970’s of a class of drugs called “ACE inhibitors” now widely used against hypertension. Heart patients owe gratitude to the eastern Green Mamba, whose venom impairs its victim’s nerves and blood circulation. A key peptide from the venom is used to make CENDERITIDE which lowers blood pressure and reduces fibrosis in a failing heart but also shields the kidneys from an overload of salt and water.
Our own experience of three decades in documenting the reptiles in general and snakes in particular has opened a world of possibilities in conservation of threatened reptiles and their habitats. The larger picture involves preservation of all reptile species, which will hold a clue to the discovery of new drugs for potential medicinal treatments and cures. The therapeutic effects of a wide variety of venom, when used the right way, would be a life saver. After all, life is very precious.
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