IL6 and osteoarthritis, knee: Experiments in different model animals showed that EA treatment could noticeably decrease the elevated expression levels of proinflammatory cytokines including IL-1β, TNF-α, and IL-6 in inflamed skin tissues [40], serum [41], peripheral nerves, and DRG [42], even synovia [43], after injection of complete Freund's adjuvant, nerve injury, knee osteoarthritis, or spinal cord ischemia-reperfusion injury [44].