Токсины Естественного Происхождения Как Своеобразные Силы Природы, Приходящие На Помощь Человеку. Яды Змей. Механизмы Токсического Воздействия. Применение В Медицине

Abstract

Modern medicine demands the development of novel medications with selectivity and activity that will reduce the adverse and toxic effects of existing medications as much as possible, while using both in monotherapy and in combination therapy. In this sense, it is more fascinating that certain poisons, which are incredible powers of nature, may be used as alternative medications to treat a wide range of illnesses, despite sometimes having very mild side effects because of their distinct structure. This work aims to cover the biochemical aspects of the poisonous mechanisms of these poisons, particularly snake venom, and to provide guidance for the precise selection of antidotes to be utilized in cases of poisoning (to the extent that the antidote’s efficiency is derived from the structure of poison) and, most importantly, to identify the phenomenon of curing effects on one or more organ systems. When a drug’s toxic property is primarily a continuous manifestation of its pharmacological effect, as is the case with one of the toxins found in the venoms of the widest variety of snakes discussed in the work (cobra, viper, etc.), the effect’s target is the sodium channels in the skeletal muscles, in CNS and PNS, whereas in toxins that exhibit a hemorrhagic impact the target is blood vessels. For toxins with a peptide structure- when the altrenagin-C protein is detached from the poison - the target is the myocardium, which will result in an increase in the latter’s contractility. If the tetrodotoxin or saxitoxin (mollusc poison) with a low molecular structure due to the guanidine residue (a structural analogue of the hydrated sodium ion) - an active ingredient, penetrates through the cracks of the sodium channels, acting as a molecular “stopper”, having the antiarrhythmic, pain-relieving effect in therapeutic doses, then bradykinin-potentiating peptides (cobra venom) lead to a decrease in arterial pressure. As a result, blood angiotensin decreases and bradykinin concentration increase. Hence, long-acting antihypertensive drugs have been made on their premise, whereas poisons containing Na-diuretic peptides can cause extreme orthostatic hypotension. The bite of pit vipers (particularly snakelets) affects the resistance of the blood system, causing hypofibrinogenemia, thrombocytopenia, and hemolysis of erythrocytes. The alternagin-C protein separated from the African viper increases myocardial contractility, which may be valuable in myocardial infarction, when the pumping work of the heart is failed, and sarafotoxin found in a few species of viper leads to the ventricular dysfunction and arrhythmia. It is interesting to note that the inclusion of tetradotoxin in a biodegradable polymer reduces its toxicity, to the extent that the poison is released gradually during hydrolysis in the body, and the anesthetic effect is maintained for quite a long time.