These epigenetic-induced changes in chondrocytes skew the balance the dictate cartilage homeostasis and induces alterations of the ECM and cartilage integrity that promote development of OA. Loss of biomechanical function of cartilage during aging has been associated with a decrease in glycosaminoglycan content ,which is normally deposited by chondrocytes. Besides direct modulation of the EMC components has been proposed to mediate cartilage decay. Age-dependent accumulation and consequent cross-linking of advanced glycation end products (AGE) in collagen has been shown to increase cartilage stiffness, which makes it brittle and impairs it’s load-absorbing function. Moreover ,chondrocytes express the receptor for AGE (RAGE) and engagement of the receptor induces the production of cartilage-degrading enzymes. Together, age – related changes in chondrocytes and components of ECM crucially impair the function of cartilage and its capacity to cope with mechanical or environmental stress factors ,which is likely to predispose to OA development.