Preventative treatment of red light-emitting diode protected osteoarthritis-like chondrocytes from oxidative stress-induced inflammation and promoted matrix gene expression

Abstract Background Osteoarthritis (OA) has become the most common type of arthritis, and the cellular and molecular mechanisms involved in OA is complex and not fully understood. Inflammation and matrix degradation have been indicated to play vital roles in pathogenesis of OA. Apart from biochemical molecules such as anti-oxidants which have been suggested to reduce inflammatory responses, photobiomodulation has become interesting targets for developing therapeutic strategies of cartilage repair and regeneration. Methods To investigate the effect of photobiomodulation on OA, red light-emitting diode (LED) was preventatively applied to hydrogen peroxide induced OA-like chondrocytes. Lumen density was measured for the level of free radicals and gene expression of IL-1β, TNF-α, MMP-1, MMP-13, and COL-2 was analyzed. Significant Findings Our results showed that pre-treatment of 635-nm LED for 2 h significantly reduced free radical formation (from 100% to 8.25%) and inflammatory gene IL-1β, TNF-α expression in OA-like cells while matrix gene COL-2 was enhanced. Furthermore, combination of preventative LED treatment with anti-oxidant(s) (vitamin E or/and resveratrol) exerted synergistic effects of anti-inflammation and MMP-13 reduction. In conclusion, preventative LED irradiation combined with anti-oxidants provides a novel therapeutic strategy for treating early OA prior to the progression of the disease.