Summary:
The review is aimed at the well-known chronic musculosceletal disorders, osteoarthritis (OA) and
rheumatoid arthritis (RA), and their increasing incidence during ageing. Especially, collagen type
II undergoes age-related non-enzymatic covalent modification (NECM), advanced glycation endproducts
(AGE) form, which then accumulate in the articular cartilage. Increased cartilage accumulation
of AGE results in cartilage quality alteration and decreases its mechanical damage resistance.
This finally contributes to degeneration of collagen fibril network and to initiation and/or progression
of joint damage. The molecular events of AGE formation represent reactive oxo-group of the
sugar and amino-group of the target molecule condensation (so-called Maillard reaction). This
reaction is potentiated by hyperglycemia and oxidative stress. Increased tissue accumulation of
AGE is seen not only during the natural process of aging but also during different pathologic
conditions (e.g. diabetes, renal insufficiency, some inflammatory and primary degenerative disorders).
AGE role in the inflammatory cell response or even in the initiation of the complex autoimmune
process in RA has been considered in recent years. Special cell receptor for AGE (RAGE) is
important for inflammatory cell activation and the presence ofRAGEon many cell types has already
been described. This paper also points at AGE presence in body fluids and tissues, at the usefulness
of their detection to follow up the disease activity of various disorders, at the attempts to elucidate
pathogenesis of these disorders, and also at the utility of AGE inhibitors, which could be of potential
significance slowing the disease progression.
Key words:
osteoarthritis (OA),rheumatoid arthritis (RA), non-enzymatic covalent modification
(NECM), Maillard reaction, advanced glycation endproducts (AGE),
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