Eicosapentaenoic acid and docosahexaenoic acid moderate inflammation in porcine cartilage explants

Objective: To characterize the effects of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) and arachidonic acid (ARA) in various combinations on indices of inflammation in recombinant porcine IL-1 beta stimulated porcine articular cartilage explants. Methods: Cartilage was obtained from the humeral-ulnar joints of Yorkshire x Landrace market sized gilts. Explants were harvested from the humeral-ulnar joints within 8 h of slaughter. Explants were allocated to culture plates and cultured in 1 mL of Dulbecco’s Modified Eagle serum free medium for 24 h with 10% fetal bovine serum. At 48 and 72 h, 1 mL of treatment media containing fatty acids and 15 ng/mL of recombinant porcine IL-1 was added to each well. At 48, 72, and 96 h after cartilage was allocated to wells, media were removed from each well and reserved for analysis. Media were analyzed for proteoglycan, nitric oxide (NO), interleukin-6 and prostaglandin E2 concentrations. Results: In general, when EPA and/or DHA are supplemented to explants in combination with linoleic acid (LA) NO and prostaglandin E2 release is decreased. Explants treated with 25 μg/mL DHA released 53% less NO into the media than explants treated with the same level of EPA and 60% less than explants treated with LA alone. Conclusions: These data demonstrate that EPA and DHA are capable of modulating the inflammatory response on porcine articular cartilage in vitro.