IL6 and osteoarthritis: The role of pro-inflammatory cytokines, including IL-6, IL-1β, TNF-α, IL-33, and IL-8, secreted because of the activation of downstream pro-inflammatory signaling and anti-inflammatory cytokines, including IL-10 and IL-37, in inflammation, macrophage polarization, and osteoarthritis, has been reported [4,5,6,7,8,9,10,11,12,13,14].