Alterations in Human Articular Cartilage N-glycan Profiles
with Cuff Tear Arthropathy

Abstract

Osteoarthritis (OA), which is a progressive degenerative joint disease, is one of the most common forms of arthritis. Therefore, OA poses a significant public health problem. However, the etiology of OA still remains poorly understood. Glycobiology, defined as the analysis of the biological function of sugar chains covalently bound to proteins and lipids, has been recently applied to molecular-based investigations. Several studies have shown that glycan modifications of proteins contribute to the pathogenesis of some diseases. In this study, we attend to the relationship between human articular cartilage N-glycans and cartilage degradation such as cuff tear arthropathy. In this study, we first showed alterations in the N-glycan pattern of human articular cartilage between a normal group and a cuff tear arthropathy group. By comparing the N-glycan pattern obtained from these groups, we showed that the composition of human articular cartilage N-glycans significantly changed with cuff tear arthropathy. In addition, these N-glycans were localized on the chondrocyte surfaces and in the cytoplasm. The N-glycan modifies almost all protein after translation. Several reports showed that intercellular reactions, the receptor workings, and the quality control of glycoprotein are controlled by changing the composition of N-glycans. The N-glycans identified in this study are expected to attach to the glycoproteins and the receptors on the chondrocyte surface, and to contribute heavily to the degradation of articular cartilage. Future studies are required to determine the biological roles of the N-glycans identified here in OA pathogenesis.