[Effects of electroacupuncture on the activity and polarization phenotype of microglia in anterior cingulate cortex of rats with knee osteoarthritis accompanied by chronic pain and related negative emotions].

Researchers in China have discovered how electroacupuncture may help relieve both pain and anxiety in people with knee osteoarthritis. The study examined rats with knee osteoarthritis who developed chronic pain and anxiety-like behaviors. Scientists focused on a brain region called the anterior cingulate cortex, which processes both pain and emotions. The researchers treated one group of animals with electroacupuncture at two specific points: Yanglingquan (GB34) and Dubi (ST35), both located near the knee. The treatment involved 15-minute sessions once daily for two weeks, using electrical stimulation at specific frequencies. Results showed that electroacupuncture significantly reduced pain sensitivity and anxiety behaviors compared to untreated animals. The treatment worked by calming overactive immune cells in the brain called microglia and shifting them toward an anti-inflammatory state. Specifically, electroacupuncture decreased inflammatory proteins (TNF-α and IL-1β) while increasing anti-inflammatory proteins (IL-10). It also reduced the pro-inflammatory M1 form of microglia while increasing the healing M2 form. This suggests electroacupuncture doesn't just address knee pain locally but also modulates brain inflammation that contributes to both chronic pain and emotional distress. For people with knee osteoarthritis experiencing both pain and mood changes, electroacupuncture may offer benefits beyond simple pain relief by addressing underlying neuroinflammation. If considering acupuncture treatment, seek a qualified, licensed acupuncturist experienced in treating osteoarthritis and chronic pain conditions.

This animal study investigated electroacupuncture's effects on microglial activity and polarization in the anterior cingulate cortex of rats with monosodium iodoacetate-induced knee osteoarthritis. Twenty rats received MIA injection; 10 were treated with electroacupuncture at GB34 and ST35 (2 Hz/100 Hz, 2 mA, 15 minutes daily for 10 sessions) beginning day 15 post-injection. Compared to model controls, electroacupuncture significantly improved thermal withdrawal latency, mechanical withdrawal threshold, and open field test parameters (P<0.01). Western blot analysis revealed decreased TNF-α and IL-1β with increased IL-10 expression (P<0.05). Immunofluorescence demonstrated reduced Iba-1 expression and CD68/Iba-1 co-expression (M1 phenotype) with increased CD206/Iba-1 co-expression (M2 phenotype) (P<0.01). Clinical relevance: Electroacupuncture at local knee points modulates central neuroinflammation by inhibiting microglial activation and promoting M2 polarization in pain-processing brain regions, supporting its use for KOA-associated chronic pain and comorbid anxiety.