Tingly Szechuan Spice May Help Treat Chronic Pain
A tingly Asian spice frequently found in Szechuan cuisine might help treat patients with chronic pain, a new study suggests.
Researchers at the University College London found that the Szechuan pepper mimics the sense of touch in the brain. The spice chemically activates light-touch fibers on the lips and tongue and sends the equivalent of 50 light taps to the brain every second.
Researchers said the latest research helps provide insight into the complex interactions between the senses of taste and touch, and could potentially lead to a greater understanding of the cause of the tingling sensations experienced by many chronic pain patients.
"This is the first time that we've been able to show how chemicals activate touch fibers, inducing a measureable frequency. We know that natural products like chili, mustard oil and menthol can activate the thermal and pain fibers in the skin, but we wanted to find out why Szechuan pepper specifically works on the light-touch fibers, producing a conscious sensation of touch and that distinctive tingling feeling," lead researchers Dr Nobuhiro Hagura of the UCL Institute of Cognitive Neuroscience, said in a news release.
In the study, researchers applied Szechuan pepper to the lips of study participants. Afterwards, participants were asked to match the frequency of the resulting tingling sensation by adjusting a vibrating stimulus, either higher or lower, on their fingertips.
The findings revealed that an active ingredient in the pepper stimulates specific RA1 fibers in the lips and tongue. Researchers explained that these fibers are responsible for transmitting touch sensation and sending the equivalent of a light tap on the skin to the brain at the rate of 50 times per second.
"What we found was that a unique active ingredient in the pepper, called sanshool, activates these fibers, sending a highly specific signal to the brain. Szechuan peppers and physical touch sensations share this same pathway to the brain," Hagura said.
"We hope that laboratory studies of the tingling sensations caused by sanshool could help to clarify the brain processes underlying these sensations, and how they are related to pain in some cases," he added.