Topic:Chondrocytes
Chondrocytes are specialized cells found in the cartilage of horses, responsible for maintaining the extracellular matrix and overall cartilage health. These cells play a role in the synthesis and turnover of cartilage components such as collagen and proteoglycans. In equine research, chondrocytes are studied to understand their function in joint health and disease, particularly in conditions like osteoarthritis. Factors influencing chondrocyte activity include mechanical stress, biochemical signals, and genetic factors. This page compiles peer-reviewed research studies and scholarly articles that examine the biology, regulation, and clinical significance of chondrocytes in equine joint health and disease.
Adverse conditions in vitro stimulate chondrocytes to produce prostaglandin E2 and stromelysin. Chondrocytes subjected to adverse culture conditions in vitro are stimulated to produce the eicosanoid prostaglandin E2 (PGE2) and the neutral metalloproteinase stromelysin (proteoglycanase). This indicates the potential role of the chondrocyte in cartilage degeneration in equine clinical joint disease and suggests a mechanism which may be involved in the potentiation of the effects of other inflammatory mediators. Therefore, adverse conditions within the joint, such as decreased pH in an inflammatory focus and decreased access of nutrients to deeper layers of cartilage, might contribute to th...
Osteochondrosis in the horse–searching for the key to pathogenesis. This paper reviews current developments in equine osteochondrosis complex and the clinical syndromes associated with it. Although the primary lesion has been defined as a failure of endochondral ossification, its definitive cause is unknown and appears to involve heredity, growth rate, nutrition, mineral imbalance, endocrinological dysfunction and biomechanical trauma. Despite the international importance of osteochondrosis in horses, surprisingly few controlled investigations have been performed on its pathogenesis. The studies that have been conducted suggest that local effects on differenti...
Polysulfated glycosaminoglycan accelerates net synthesis of collagen and glycosaminoglycans by arthritic equine cartilage tissues and chondrocytes. Low molecular weight polysulfated glycosaminoglycan (PSGAG) stimulated net collagen and glycosaminoglycan synthesis by normal and arthritic equine fetlock cartilage tissues in organ culture. Arthritic tissues were more sensitive to PSGAG stimulation. The rates of cartilage-specific type-II collagen and chondroitin sulfate-rich glycosaminoglycan synthesis by confluent chondrocyte cell cultures obtained from normal and arthritic equine cartilage tissues were increased by 25 and 50 mg of PSGAG/ml. Cells from arthritic cartilage were also more sensitive to the presence of PSGAG. In addition, conce...
Identity of the E-series prostaglandin produced by equine chondrocytes and synovial cells in response to a variety of stimuli. Although an E-series prostaglandin has previously been identified in equine inflammatory exudate, the identity of this eicosanoid as PGE2 has not been confirmed. The objective of this study was the specific characterisation of the prostaglandin produced by equine cells in the presence of an inflammatory stimulus. By using two radioimmunoassays, a relatively non-specific PGE2 assay and a more specific PGE1 assay, it has been possible to identify the E-series prostaglandin produced by equine chondrocytes and synovial cells, in response to a variety of stimuli, as PGE2.
Pathogenesis of degenerative joint disease. Proteoglycan degradation is central to the development of degenerative joint disease. Proteoglycans may be degraded by lysosomal enzymes from chondrocytes, synoviocytes or leucocytes. Collagen and matrix degradation occurs either by direct damage or due to degrading enzymes released into synovial fluid. Once the pathological sequence has begun it continues in a cyclic manner unless arrested by the ability of chondrocytes to synthesise sufficient matrix components. Treatment should ideally be directed to this end.
Caveolar system of the articular chondrocyte. Tangential articular chondrocytes contain a complex system of membrane invaginations called caveolae. Caveolae are about 600 A in diameter, open to the extracellular space, and may attract and sequester calcium ions. On the average each chondrocyte has approximately 17 700 caveolac. This chondrocytic caveolar system appears remarkably similar to the caveolar system of smooth muscle cells, and it is proposed that chondrocytic caveolae may contribute to an excitation-contraction coupling mechanism similar to the mechanism in smooth muscle cells.