Intra-articular injectable poly (gallic acid) and hyaluronic acid reduce inflammation and oxidative stress for the treatment of osteoarthritis.

Knee osteoarthritis (KOA) is a degenerative disease associated with chronic pain, cartilage degradation, subchondral bone sclerosis, and synovial inflammation. The search for new molecules capable of reducing the release of pro-inflammatory cytokines has led to the investigation of poly (gallic acid) (PGAL), an enzyme-mediated polyoxidized form of gallic acid, due to its relatively high stability and antioxidant activity. Experimental evidence suggests that PGAL (100 ppm) is capable to decrease IL-6, TNF-α, and IL-1β levels in human osteoarthritic synoviocytes. Additionally, a combination of PGAL with hyaluronic acid (HA) decreases the production of reactive oxygen species (ROS) and hydrogen peroxide (H2O2). In silico analysis demonstrated that PGAL interacts favorably with HA, primarily through key electrostatic interactions. These properties of PGAL-HA might be useful to develop new treatments for KOA, representing a promising and effective strategy to address the inflammatory and oxidative aspects associated with this degenerative pathology and providing new therapeutic options to improve the quality of life of KOA patients.