Assistant Professor K.S. Hegde Medical Academy Mangalore, Karnataka, India
Abstract: Knee osteoarthritis is a burdensome condition since it affects the quality of life and is also immoderately expensive for operative management. In a quest for effective alternative solutions, nutraceutical supplementation has been extensively investigated over the past decade due to its ability to attenuate reactive oxygen species (ROS) formation within chondrocytes, a critical step in the pathogenesis of this disease. Recently, there have been some tangible advances in the development of natural nutraceutical supplements, such as quercetin and vitamin C as the substitute for growth factors to repair cartilage defects. Understanding the possible protective mechanisms by supplementation of quercetin and vitamin C will have clinical implications in the treatment of OA. The present was conducted to examine the effect of quercetin and/or vitamin C on cell vitality and phenotypic properties of human chondroprogenitors (CPs) and to determine the effect of quercetin and/or vitamin C supplementation on the differentiation potential of chondroprogenitors into chondrocytes. FACS analysis of CPs was confirmative for the phenotypic expression of positive markers (CD73, CD90, CD105, CD146, CD166, CD271, collagen type II, aggrecan), and negative markers (CD45 and HLA-DR). CPs supplemented with a combination of quercetin (10 μM) and vitamin C (100 μM) exhibited decreased ROS activity, least apoptotic cells and superior chondrogenesis as confirmed by the mRNA expression of Collagen type II α1, Aggrecan, Collagen type XI α1, Collagen type X, SOX9, Cartilage oligomeric matrix protein (COMP), transforming growth factor-β (TGF-β), fibroblast growth factor-2 (FGF2), Cartilage-derived retinoic acid-sensitive protein (CD-RAP) by qPCR. The present study results are conclusive of the synergistic potential of quercetin (a multiple signaling inhibitor) and vitamin C (an antioxidant agent) in possible prevention of cellular damage and enhanced cartilage regeneration. However, preclinical investigations are required priorly, keeping in view of the transplantation approaches of quercetin and vitamin C supplemented CPs as a clinical source for cartilage tissue regenerative therapies.
