Chondroprotective role of whole grape polyphenols in stimulated SW 1353 cells (830.27)

Abstract

In aging, increases in oxidative stress and inflammation cause an imbalance in the metabolic activity of chondrocytes leading to onset and progression of osteoarthritis. Resveratrol, a polyphenol rich in grapes has shown to inhibit chondrocyte apoptosis and suppress cyclooxygenase (COX‐2). Our study investigated the effect of whole grape polyphenols on cartilage cell integrity and markers of cartilage health using SW 1353 human chondrosarcoma cells that are compatible to primary chondrocytes. Whole grape polyphenols (WGP) were extracted from grape powder and concentrations were determined using Folin‐Calteau assay. For all experiments, cells treated with WGP were stimulated with the inflammatory compound, tert‐butyl hydroperoxide (tbHP). Cell proliferation significantly (p<.05) increased in a dose dependent manner with WGP at 20ug/ml (147% vs. Control). Cartilage degradation as indicated by glycoprotein‐39 (YKL‐40) levels was significantly lower with the three highest doses of WGP in comparison to control and tbHP stimulated cells. Toluidine blue and Safarin O staining indicated increase presence of type II collagen and proteoglycan in WGP treated cells. Using In‐Cell colorimetric ELISA, we did not observe a significant effect on COX‐2 protein expression with any WGP doses. Elucidation of mechanisms by which WGP protect cartilage cell destruction in presence of an inflammatory agent are warranted. Grant Funding Source: Supported by California Table Grape Commission