Effects of Snake Venom Polypeptides on Central Nervous System

Abstract

The nervous system is a primary target for animal venoms as the impairment of its function results in the fast and efficient immobilization or death of a prey. There are numerous evidences about effects of crude snake venoms or isolated toxins on peripheral nervous system. However, the data on their interactions with the central nervous system (CNS) are not abundant, as the blood-brain barrier (BBB) impedes penetration of these compounds into brain. This updated review presents the data about interaction of snake venom polypeptides with CNS. Such data will be described according to three main modes of interactions: - Direct in vivo interaction of CNS with venom polypeptides either capable to penetrate BBB or injected into the brain. - In vitro interactions of cell or sub-cellular fractions of CNS with crude venoms or purified toxins. - Indirect effects of snake venoms or their components on functioning of CNS under different conditions. Although the venom components penetrating BBB are not numerous, they seem to be the most suitable candidates for the leads in drug design. The compounds with other modes of action are more abundant and better studied, but the lack of the data about their ability to penetrate BBB may substantially aggravate the potentials for their medical perspectives. Nevertheless, many such compounds are used for research of CNS in vitro. These investigations may give invaluable information for understanding the molecular basis of CNS diseases and thus lay the basis for targeted drug design. This aspect also will be outlined in the review.

Priapism following a juvenile Russell’s viper bite: An unusual case report

“…Since Russell's viper venom has neurotoxic manifestations, it is worth considering the action of this venom via brain synaptosomes to demonstrate if this unusual event may be linked with the rare effects on the pituitary gland or peripheral tissues. It is noteworthy that the venom proteins may largely act on the peripheral tissues as they don't usually penetrate the blood-brain barrier [21] except some toxins (e.g., apamin from bee venom) that were reported to pass through this barrier [21,22]. Other lines of enquiry resulting from some priapism case studies suggest α2δ1 subunits of voltage-gated calcium channels [23], the target of pregabalin as responsible for this condition.…”

Comparative analysis of intestinal bacteria among venom secretion and non-secrection snakes

“…In particular, known as “liquid gold” in the international market, and costing dozens of times more than gold, snake venom is insufficiently available as animal medicine in the international market. Due to its proven antivirus 7 , anti-inflammatory 8 , and immune regulatory 8 functions, snake venom not only has been in use as tranquilizer 9 , and for colorectal cancer treatment 10 , but also can be developed into health care products such as snake wines 11,12 .…”

Form and Function of the Vertebrate and Invertebrate Blood-Brain Barriers

“…Relative to amphibians, which have been used as animal models (see Section 5), and to fish (also used as models for human health and in the context of aquatic and marine contamination, see Section 6), the blood-brain barrier of reptiles has been largely ignored, apart from a few key studies, many now decades old. However, ironically, reptiles nonetheless feature prominently in BBB research-not because of the barrier characteristics of reptiles themselves, but rather for the variety of effects of their venoms (especially snake venoms) on the BBB of mammals [125][126][127][128]. Here, we review literature on the function of the reptile blood-brain barrier, which we recognize reads more like a fragmented, disjointed list of findings rather than a comprehensive account.…”