SNAKE VENOM USED IN MEDICINE DEVELOPMENT – JOHNS HOPKINS UNIVERSITY

By The News-Letter on February 14, 2013

The snake — the very creature considered a devil by some religions, feared as a resurrecting deity by ancient Egyptians and a cause for panic throughout the world — might just have a shot at public redemption.

Here in Maryland, only two to six people a year are bitten by snakes, and these bites rarely result in death. However, the thought of what a snake’s deadly toxins can do in minutes still sends chills down our spines. But what if we were told that snakes held the cure to heart disease, high blood pressure, multiple sclerosis or even cancer?

Snake venom varies in each of the 3,150 registered snake species worldwide. Within these types of venom, even more toxic proteins, peptides and molecules exist. The most potent of these toxins belongs to a group of around 600 species whose venom is known to be dangerous to humans. However, smaller traces of venom are also present in the wider group of 3,000 or so species of snakes. These lesser-known toxins have their own unique and valuable biochemical properties.

In general, venom targets two major body functions: the neuromuscular and cardiovascular systems, although many variations and exceptions exists. Since these systems are often implicated in many human diseases and conditions, venom makes an ideal drug template for human exploitation.

Already, different animal venoms have taken part in at least 10 different medications, a number that is certain to grow as research and clinical trials continue.

“An estimated 20 million toxins in well more than 100,000 venomous animal species exist in nature,” Zoltan Takacs, pharmacologist and founder of the World Toxin Bank, said.

“Science has only studied about 1,000 toxins in depth, yet we have major life-saving, best-selling, and first-in-a-class pioneer medications originating from toxins. It is a goldmine for medicine.”

After earning a Ph.D. from Columbia in evolutionary studies on cobra venom resistance, and serving on the University of Chicago faculty, Takacs is taking the toxin-tweaking to a different level. He now travels the world in search of snakes and other venomous creatures, collecting their tissues for toxin RNA and DNA, and assembling toxin libraries for drug discovery. Takacs founded the World Toxin Bank project in an effort to single out the best of toxins for medicinal development. The toxin libraries offer the opportunity to isolate those toxin candidates that have the most desirable effect on pharmaceutical targets.

“We are expanding on our Designer Toxins technology — a constantly growing library of natural animal toxins and their combinatorial variants that are screened against a target of interest…” Takacs said. “The beauty of this is that variants in the library are biased toward the target to start with, and can handle thousand to millions of toxin variants at once.”

From these findings, it has become easier to search for the particular chemicals needed for a specific reaction. Toxins in snakes have been around since before they became apparent in potent venoms.

They used to fulfill other, non-toxic physiological functions. In fact, snakes’ ability to revert their toxins back into harmless molecules is one of the empowering characteristics useful in the treatment of diseases like cancer.

Integrin antagonists like contortrostatin, which can block a bond between cells and tissue, are found in some snake venom and can revert one of cancer’s invasive mechanisms to stop cells form migrating. Thus, metastasis, one of the major complications of cancer, is prevented. Takacs envisioned the most important direction the work would take with unlimited funding.

“[We would] protect the world’s habitats and species, while making all toxins available for research, drug discovery and bioengineering. These are some of the coolest and most valuable molecules that nature produced, and if we´re not acting in time we may loose the wisdom they hold.” Unfortunately, the negative image snakes currently hold has hindered the possibilities of conservation. With snake species becoming endangered by the day, potential drugs will proportionally begin dissipating as well. If public redemption became a possibility through education, snakes might just live to partake in medical breakthroughs addressing the world’s greatest health obstacles.