Electroacupuncture can Ease Fibromyalgia-related Pain by Normalizing Specific Protein Levels in the Brain, Mouse Study Suggests

Electroacupuncture can Ease Fibromyalgia-related Pain by Normalizing Specific Protein Levels in the Brain, Mouse Study Suggests

Electroacupuncture can ease pain associated with fibromyalgia by normalizing the levels of two proteins — TRPV1 and pERK — in specific regions of the brain, according to a mouse study.

These findings not only reinforce the increasing evidence supporting electroacupuncture’s benefits in alleviating chronic pain, but also shed light on potential underlying mechanisms.

The study, “Electroacupuncture reduces fibromyalgia pain by downregulating the TRPV1–pERK signalling pathway in the mouse brain,” was published in the journal Acupuncture in Medicine.

Acupuncture is an ancient healing technique of traditional Chinese medicine that has been practiced in China for more than 3,000 years to treat a variety of disorders. It has also been studied by the World Health Organization as a method for pain relief.

Acupuncture involves the strategic placement of thin sterile needles through a person’s skin at specific points in the body. In electroacupuncture, a small electrical charge is applied to the needles to stimulate these particular body points, which is thought to increase the technique’s effectiveness in treating pain.

A previous review showed that acupuncture safely and effectively lessens chronic pain and improves the quality of life of people with fibromyalgia.

While the molecular mechanisms underlying acupuncture’s therapeutic benefits remain largely unknown, evidence suggests that it involves changes in both the peripheral nervous system and the central nervous system.

Of note, the peripheral nervous system comprises all the nerves found outside the central nervous system, while the central nervous system includes the brain and spinal cord.

TRPV1 is a calcium channel present in nerve cells and is activated by several physical and chemical stimuli, including high temperatures and acid solutions. The channel’s activation in nerve cells was shown to increase the levels of pERK, a signaling protein of the ERK family, which is involved in several key cellular processes.

TRPV1 and pERK have been associated with pain processes and found at higher-than-normal levels in specific regions of the nervous system related to pain, including the peripheral dorsal root ganglion, amygdala, and thalamus, in a mouse model of induced fibromyalgia.

In these animals, fibromyalgia is triggered by repeatedly injecting their muscles with acid solutions that progressively increase their sensitivity to pain, thereby mimicking the symptoms of the disease in humans.

Previously, a team of researchers in Taiwan showed that electroacupuncture could ease pain in this mouse model and hypothesized these benefits were associated with the suppression of the TRPV1-pERK signaling pathway in the dorsal root ganglion.

In the new study, the same team of researchers confirmed the association between electroacupuncture’s therapeutic benefits in pain management and the reduction of TRPV1 and pERK levels in several brain regions of the same mouse model of fibromyalgia.

They analyzed the effects of electroacupuncture on the levels of TRPV1 and pERK in the thalamus, amygdala, and somatosensory cortex — a brain region that receives and processes sensory information from the entire body — of mice with induced fibromyalgia.

Mice were injected with an acid saline solution (fibromyalgia mice) or a saline solution (healthy mice) in their calf muscle. Electroacupuncture was performed at a specific point in the anterior lower leg muscle (true treatment) or at an irrelevant point in the gluteus muscle (sham treatment).

Results showed that the acid saline injection induced high sensitivity to pain in the animals’ muscle, along with increased levels of TRPV1 and pERK in the thalamus, amygdala, and somatosensory cortex. Mice injected with normal saline solution did not show any of these effects.

Unlike the sham treatment, electroacupuncture restored both pain sensitivity and the levels of TRPV1 and pERK in the three brain regions of the mice.

“We hypothesize that acid saline activates TRPV1 receptors, which contribute to the development of [high sensitivity to pain associated with fibromyalgia] via the pERK signalling pathway,” the researchers wrote, adding that electroacupuncture can reverse this effect by suppressing the TRPV1-ERK signalling pathway in the brain.

“Thus, our findings provide mechanistic evidence supporting the potential therapeutic efficacy of [electroacupuncture] for treating [fibromyalgia] pain,” they said.