Hairy, eight-legged menaces they may be, but tarantulas aren’t all bad — at least not from a medical science point of view, as a team of scientists has recently produced a working procedure for extracting the spider’s venom and using it to produce painkillers.
The list of potential donor spiders for painkiller development stretches into the thousands, with their available toxins in the millions. (It’s sort of ironic, considering how many of their comrades have been reflexively squashed underfoot by people ignorant of the fact that some of these spiders may one day save their lives.) But thankfully, researchers at Yale University have devised a method for screening this laundry list of toxins, known as “toxineering,” that can comb through each toxin and spit out its compatibility with painkiller development.
To conduct their study, Yale associate professor of cellular and molecular physiology Dr. Michael Nitabach and his colleagues screened a variety of species for the appropriate venoms. Specifically, they were looking for a toxin that blocked TRPA1, an ion channel on the surface of pain-sensing neurons responsible for inflammation and pain. But rather than essentially guess which toxins would block TRPA1, the team used their toxineering method, which employs huge stores of cloned DNA to sort out which neural pathways the toxins affect. The process opens countless doors for future research opportunity, Nitabach remarked.
“The likelihood is that within the vast diversity of spider toxins we will find others that are active against other channels important for pain,” he said in a university news release. The key difference with the TRPA1 channel is that surrounding nerve pathways are unaffected, basically implying that you will enjoy pain relief without having to worry about losing all feeling in your arm.
Through their toxineering process, the team has identified the Peruvian green velvet tarantula’s toxin as the developmental sweet spot. The spider produces a venom that, if harnessed properly, could blunt both chronic pathological pain and “normal-functioning” pain. (Think Advil and morphine.) More interesting, the team can use their method to screen the capabilities of toxins not found in nature. Effectively, because they scan through their library of toxins for a desired ion channel, rather than many channels for one toxin, whether the toxin comes from a tarantula, or some other thing, is less relevant.
More important is getting the two to match up, and through that process identifying “higher-potency and more specific molecular variants that lack deleterious effects on essential nerve functions,” Nitabach said in the release. From there, the team will rev up their screening to include tens of thousands of toxins, in the hopes of gaining as much information as possible before pharmacological approaches reach the table.
Source: Gui J, Liu B, Cao G, et al. A Tarantula-Venom Peptide Antagonizes the TRPA1 Nociceptor Ion Channel by Binding to the S1–S4 Gating Domain. Current Biology. 2014.