DURHAM, England — Ticks are one of the most feared bugs among humans, but they may provide some good after all. A new drug derived from the saliva of the disease-causing arachnids could potentially ease itching and chronic pain in humans.
The protein was discovered in the saliva of the brown-ear tick, which spreads parasites that cause East Coast fever in cattle across Africa. Now, medication made from it is hoped to one day be a replacement for opioids, which can be ineffective, have serious side-effects and can be addictive.
Researchers from Durham and Newcastle universities in England say that the protein, called Votucalis, was able to provide both pain and itch relief in a study involving mice. The compound was discovered when researchers found the brown-ear tick was able to secrete it into their host. They say Votucalis was delivered into the host as they fed, so the host was unaware they had been bitten.
On a chemical level, the protein binds histamine produced in the body from activating resulting in reduced itch or chronic pain responses. Unlike opioids, the research shows votucalis does not enter the brain which means it is far less likely to be addictive and less likely to cause side-effects.
“Votucalis has already been tested in humans with other conditions, including conjunctivitis, without major side-effects, so the potential for this to be developed into a drug to tackle chronic pain and itching is definitely there,” says co-author Dr. Ilona Obara, of Newcastle University, in a statement. “It is amazing that a protein found in the saliva of this tiny creature could prevent chronic pain and itching in people. These are conditions that bring a huge amount of misery, and current medication displays limited efficacy, and can also often be detrimental to patients.”
The researchers say the next step towards clinical testing is to develop a delivery system to effectively administer the drug at the site of itch and pain. “Persistent or chronic pain is a huge global health challenge, which affects over 20 percent of the population,” says co-author Dr. Paul Chazot, of Durham University. “It is the single biggest reason that people in the UK visit their doctor and it is recognized as a priority disease by the World Health Organisation.
“The National Institute for Health and Care Excellence (NICE) has recommended that current opioid and gabapentinoid pain medications should not be prescribed to patients newly diagnosed with chronic pain, apart from cancer sufferers, so there is an urgent need to develop a new, long-lasting medication that is both effective and safe to use,” Chazot continues. “Our study is the first to show evidence of the anti-itch and pain relief potential of Votucalis, which is very exciting. We could be on the brink of discovering a viable alternative to opioid and gabapentinoid drugs.”
The research is published in the journal Frontiers in Pharmacology.
South West News Service writer Joe Morgan contributed to this report.