ABSTRACT
Nitric oxide (NO) has been considered as an important mediator in inflammatory phases and in loss of cartilage. In inflammatory arthritis, NO levels are correlated with disease activity and articular cartilage is able to produce large amounts of NO with the appropriate inducing factor such as cytokines. The old animals are shown to have a greater sensitivity to NO than young animals. This study evaluated the basal production of NO in normal and OA-affected chondroyctes from young and old patients and compared the levels of NO formation in response to IL-1beta. The results showed that the basal levels were 7-fold higher in old chondrocytes than those of young cells. However, the IL-1beta induced NO production was seen to decrease with age. Aminoguianidine (AG), a competitive inhibitor of iNOS, inhibited NO formation completely in both chondrocytes from young and old individuals. However, at the same concentration of AG it caused partial inhibition of NO and iNOS formation in chondrocytes from OA-affected individuals. In addition, although the IL-1beta induced NO production was much lesser than that of young chondrocytes, the inhibition of collagen production by IL-1beta was prominent in old chondrocytes and OA-affected chondrocytes. These results suggest that age-related differences in the regulation of NO production and collagen production, which may affect the ageing cells and osteoarthritic changes in some way.
Subject(s)
Humans , Aging/physiology , Cartilage, Articular/physiopathology , Cells, Cultured , Chondrocytes/metabolism , Collagen Type II/metabolism , Enzyme Inhibitors/pharmacology , Guanidines/pharmacology , Interleukin-1/pharmacology , Nitric Oxide/biosynthesis , Osteoarthritis/metabolismABSTRACT
Nitric oxide (NO) has been considered as an important mediator in inflammatory phases and in loss of cartilage. In inflammatory arthritis, NO levels are correlated with disease activity and articular cartilage is able to produce large amounts of NO with the appropriate inducing factor such as cytokines. The old animals are shown to have a greater sensitivity to NO than young animals. This study evaluated the basal production of NO in normal and OA-affected chondroyctes from young and old patients and compared the levels of NO formation in response to IL-1beta. The results showed that the basal levels were 7-fold higher in old chondrocytes than those of young cells. However, the IL-1beta induced NO production was seen to decrease with age. Aminoguianidine (AG), a competitive inhibitor of iNOS, inhibited NO formation completely in both chondrocytes from young and old individuals. However, at the same concentration of AG it caused partial inhibition of NO and iNOS formation in chondrocytes from OA-affected individuals. In addition, although the IL-1beta induced NO production was much lesser than that of young chondrocytes, the inhibition of collagen production by IL-1beta was prominent in old chondrocytes and OA-affected chondrocytes. These results suggest that age-related differences in the regulation of NO production and collagen production, which may affect the ageing cells and osteoarthritic changes in some way.
Subject(s)
Humans , Aging/physiology , Cartilage, Articular/physiopathology , Cells, Cultured , Chondrocytes/metabolism , Collagen Type II/metabolism , Enzyme Inhibitors/pharmacology , Guanidines/pharmacology , Interleukin-1/pharmacology , Nitric Oxide/biosynthesis , Osteoarthritis/metabolismABSTRACT
PURPOSE: Bone and cartilage were manufactured by using tissue engineering of mesenchymal stem cell (MSC) which can differentiate into variety of cell types. MATERIAL AND METHOD: MSC was isolated and cultured from the rabbit weighing 500g, and it was seeded into PGA mesh and pre-cultured for 1 week with different TGF- beta 3 treated conditions. It was implanted into nude mice and tissues generated were recovered from 1, 2, 3, 4, 8 ,and 12 weeks respectively. Degree of bone and cartilage formation was analyzed with histology and immunohistochemistry assay. RESULT: Pre-culture condition with TGF- beta 3 treatment showed early start of chondrogenic differentiation, and degree of bone and cartilage formation was promoted as time passed. But both of the cases differentiated into complete bone after 12 weeks. CONCLUSION: The results show that pretreatment of TGF- beta 3 promotes the differentiation process in vivo condition under the in vivo system where MSC differentiate into bone via cartilage formation.