Synovial fluid analyses detect and differentiate proteoglycan metabolism in canine experimental models of osteoarthritis and disuse atrophy

Phytoestrogen (Daidzein) Promotes Chondrogenic Phenotype of Human Chondrocytes in 2D and 3D Culture Systems

Clinical investigations have shown a significant relationship between osteoarthritis (OA) and estrogens levels in menopausal women. Therefore, treatment with exogenous estrogens has been shown to decrease the risk of OA. However, the effect estrogen has not been clearly demonstrated in the chondrocytes using phytoestrogens, which lack the specific side-effects of estrogens, may provide an alternative therapy. This study was designed to examine the possible effects of phytoestrogen (daidzein) on human chondrocyte phenotype and extracellular matrix formation. Phytoestrogens which lack the specific side-effects of estrogens may provide beneficial effect without causing hormone based side effect. Human chondrocytes cells were cultured in 2D (flask) and 3D (PCL-CA scaffold) systems. Daidzein cytotoxic effect was determined by MTT assay. Chondrocyte cellular content of glycosaminoglycans (GAGs), total collagen and chondrogenic gene expression were determined in both culture systems after treatment with daidzein. Daidzein showed time-dependent and dose-independent effects on chondrocyte bioactivity. The compound at low doses showed significant (p < 0.05) increase in total collagen and GAGs production at similar levels in 2D and 3D culture environment. The mRNA levels of Collagen II and Sox9 were increased significantly (p < 0.01) after the treatment while the upregulation in COMP expression was statistically insignificant (p > 0.05). The expression levels of Fibronectin, Laminin and Integrin β1 were significantly increased especially in 3D culture system. This study was illustrated the potential positive effects of daidzein on maintenance of human chondrocyte phenotype and extracellular matrix formation suggesting an attractive and viable alternative therapy for OA.

Hyaluronan production and chondrogenic properties of primary human chondrocyte on gelatin based hematostatic spongostan scaffold

BACKGROUND

Autologous chondrocyte transplantation is a promising technique for treatment of cartilage defects. Three dimensional chondrocyte cultures on a scaffold are widely used to retain the chondrogenic phenotype. Using a biodegradable gelatin scaffold is one option for the cell delivery system, but molecular and histological studies of the method have not yet been done.

METHODS

We evaluated the chondrogenic property of the primary human chondrocyte on a gelatin scaffold as compared to a collagen scaffold over a period of 21 days. We examined the production of glycosaminoglycan by quantitative and histological analysis. Gene expression of cartilage-associated molecules was assessed by quantitative RT-PCR.

RESULTS

The gelatin scaffold showed the ability to promote chondrocyte expansion, chondrogenic phenotype retention at molecular and mRNA levels.

CONCLUSIONS

This scaffold is thus suitable for use as an in vitro model for chondrocyte 3D culture.

Biomarkers of joint tissue metabolism in canine osteoarthritic and arthritic joint disorders

OBJECTIVE

To explore the levels of matrix metalloprotease-3 (MMP-3), tissue inhibitor of metalloproteases-1 (TIMP-1), 5D4 keratan sulfate, and two 3B3 chondroitin-sulfate epitopes in several canine osteoarthritic and inflammatory arthropathies.

METHODS

Blood and synovial fluid were obtained from 103 dogs with rupture of the anterior cruciate ligament (ACLR), osteochondritis dissecans (OCD), fragmented coronoid process (FPC), patella luxation (PL), hip dysplasia (HD) or infectious arthritis. Dogs with non-musculosceletal disorders were used as controls. The biomarkers were measured by immunoassays.

RESULTS

Median levels of synovial MMP-3, TIMP-1 and molar ratios of MMP/TIMP-1 were significantly higher in the arthritis than in the control group. The release of 5D4 keratan sulfate epitope and serum 3B3 neoepitope was reduced in arthritis patients. Increases in synovial TIMP-1 in OA were less pronounced and the molar ratio of MMP-3/TIMP-1 remained far below 1.0, demonstrating a surplus of the protease inhibitor. In osteoarthritic patients median levels of synovial 5D4 keratan sulfate were up-regulated after ACLR and PL and were inversely correlated with increasing duration of lameness. Serum TIMP-1 levels were significantly reduced in the joint disorder group when compared with the control group.

CONCLUSION

Our observations present the TIMP-1 serum level as a potential marker for the detection of degenerative changes in cartilage and also indicate that in canine OA, the MMP-3 mediated matrix destruction is not of major importance. However MMP-3 seems to be a sensitive marker for the local inflammation in canine arthritis.