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who doesn’t feel the Woman WHAT THE FUTURE HOLDS.... As for people with CIP, Woods says he doesn't know if treatment using nalox- one is an option. Long-term use of naloxone could have side effects. What Woods can say, definitively, is that the mice in the experiment felt as little pain as mice who did not have the Nav1.7 channel naturally. Woods, his team, and the rest of the field are working to fill in the re- search gaps to start answering these questions for humans. “We hope to see our approach tested in human trials by 2017 and

STUDY METHODOLOGY Studying mice genetically modified to be without the Nav1.7 channel, Wood found that such mice had bodies that dis- played a large increase in certain genes responsible for creating opioid peptides. Opioid peptides occur naturally in the body as the body’s painkiller and have a similar effect as opioids. In making more of the opioid pep- tides, the mice were blocking any feelings of pain, which might be the reason people suffering from CIP also don't feel pain. Wood thought that if he gave mice a medicine that reversed the effect of the opioid peptides, it may reverse the disorder. He gave the mice naloxone—a medication used to reverse opioid overdoses—and it worked. Wood figured the same could be done for humans. “After a decade of rather disap- pointing drug trials, we now have confirmation that Nav1.7 is a key element in human pain,” Woods says. “The secret ingredient turned out to be good old-fashioned opioid peptides, and we have now filed a patent for combining low dose opioids with Nav1.7 blockers. This should replicate the pain- lessness experienced by people with rare mutations, and we have already successfully tested this approach in unmodified mice.” CONGENITAL INSEN- SITIVITY TO PAIN (CIP) is a very rare genetic mu- tation that prevents mes- sages of physical pain from reaching the brain.

Could help in making better painkillers.

Research researcher and his team of researchers studied a 39-year-old woman with CIP. Using a laser beam and a dose of naloxone, Wood helped the woman, who elected to partici- pate anonymously, feel pain for the first time in her life. “Used in combination with Nav1.7 blockers, the dose of opioid needed to prevent pain is very low,” says Wood in an UCL release. “People

Using a test subject with a ge- netic mutation that prevents her from feeling pain, scientists have conducted research that shows promise in creating more effec- tive painkillers—and potentially decreasing the need for addictive opioids. Congenital insensitivity to pain (CIP) is a very rare genetic muta- tion that prevents messages of physical pain from reaching the brain. Sufferers of the disorder, as babies, will chew their lips until they bleed. Toddlers have to deal with more potential for falls, bumps and being hurt by hot or sharp things. Adults are at a high- er risk of dying prematurely. The disorder leaves those afflict- ed without channels known as Nav1.7, which carry sodium to sensory nerves. Understanding this disorder and channels of pain reception and delivery has led re- searchers to study the disorder for ways to block pain in those who don't have the disorder. Research- ers thought they could block pain transporting channels in people without CIP so they can help those with chronic and painful ailments like arthritis. HELPING A WOMAN CRY In a study published by the journal Nature, John Wood, a University College London (UCL) Wolfson Institute for Biomedical

we can then start looking into drug combinations to help the millions of chronic pain patients around the world,” Woods says. Imperial College London professor Kenji Okuse reacted to Wood’s findings to the New Scientist, saying that the research will provide more information to doc- tors about pain.

with nonfunctioning Nav1.7 produce low levels of opioids throughout their lives without de- veloping tolerance or experiencing unpleasant side effects.”

We hope to see our

“Opioids and Nav1.7 blockers could provide much stronger analgesics, but they will not necessarily be better for patients,” Okuse says. “If we take the combination therapy route, people would have to take opioids throughout the lifetime, which is not a welcome thing.”

approach tested in human trials by 2017 and we can then start looking

into drug combinations to help the millions of chronic pain patients around the world. — John Wood, University College London Wolfson Institute for Biomedical Research researcher

As for this work leading to com- plete cessation of pain, Wood tells the New Scientist that some research has found success, but nothing has led to the complete pain loss found in those that are naturally without Nav1.7 channels.