Electroacupuncture activates neurons to switch off inflammation

Abstract

Neurons that express a specific molecular marker are activated by ‘electroacupuncture’ stimulation. They can then mediate the treatment’s anti-inflammatory effects in a mouse model of the inflammatory condition sepsis.

Keywords: Immunology; Neuroscience; Physiology.

Figure 1 |. Neuronal targets of electroacupuncture.

In a treatment called electroacupuncture, certain sites on the body known as acupoints are stimulated electrically. For example, low-intensity stimulation of a leg acupoint called ST36 can reduce inflammation by activating the vagus nerve, which sends signals from the brain to the adrenal glands (located, as shown, on the kidneys), and promotes the release of anti-inflammatory catecholamine molecules such as dopamine and noradrenaline. Liu et al. used a mouse model of sepsis – a potentially fatal condition in which the inflammatory reaction to an infection gets out of control – to identify a population of sensory neurons that express the protein Prokr2 and that are needed for the anti-inflammatory effects of low-intensity ST36 stimulation, but not high-intensity stimulation (not shown). These neurons have cell bodies in the lower spinal cord, and have processes (red lines) that extend down the hindlimb and up to a brain structure called the nucleus tractus solitarius (NTS), which influences the activity of the vagus nerve.