Application of Cartilage Extracellular Matrix to Enhance Therapeutic Efficacy of Methotrexate

BACKGROUND@#Rheumatoid arthritis (RA) is characterized by chronic inflammation and joint damage. Methotrexate (MTX), a commonly used disease-modifying anti-rheumatic drug (DMARD) used in RA treatment. However, the continued use of DMARDs can cause adverse effects and result in limited therapeutic efficacy. Cartilage extracellular matrix (CECM) has anti-inflammatory and anti-vascular effects and promotes stem cell migration, adhesion, and differentiation into cartilage cells. @*METHODS@#CECM was assessed the dsDNA, glycosaminoglycan, collagen contents and FT-IR spectrum of CECM.Furthermore, we determined the effects of CECM and MTX on cytocompatibility in the SW 982 cells and RAW 264.7 cells. The anti-inflammatory effects of CECM and MTX were assessed using macrophage cells. Finally, we examined the in vivo effects of CECM in combination with MTX on anti-inflammation control and cartilage degradation in collageninduced arthritis model. Anti-inflammation control and cartilage degradation were assessed by measuring the serum levels of RA-related cytokines and histology. @*RESULTS@#CECM in combination with MTX had no effect on SW 982, effectively suppressing only RAW 264.7 activity.Moreover, anti-inflammatory effects were enhanced when low-dose MTX was combined with CECM. In a collageninduced arthritis model, low-dose MTX combined with CECM remarkably reduced RA-related and pro-inflammatory cytokine levels in the blood. Additionally, low-dose MTX combined with CECM exerted the best cartilage-preservation effects compared to those observed in the other therapy groups. @*CONCLUSION@#Using CECM as an adjuvant in RA treatment can augment the therapeutic effects of MTX, reduce existing drug adverse effects, and promote joint tissue regeneration.

Resveratrol Inhibits Nitric Oxide-Induced Apoptosis via the NF-Kappa B Pathway in Rabbit Articular Chondrocytes

Resveratrol (trans-3,4'-trihydroxystillbene), a naturally occurring polyphenolic antioxidant found in grapes and red wine, elicits diverse biochemical responses and demonstrates anti-aging, anti-inflammatory, and anti-proliferative effects in several cell types. Previously, resveratrol was shown to regulate differentiation and inflammation in rabbit articular chondrocytes, while the direct production of nitric oxide (NO) in these cells by treatment with the NO donor sodium nitroprusside (SNP) led to apoptosis. In this study, the effect of resveratrol on NO-induced apoptosis in rabbit articular chondrocytes was investigated. Resveratrol dramatically reduced NO-induced apoptosis in chondrocytes, as determined by phase-contrast microscopy, the MTT assay, FACS analysis, and DAPI staining. Treatment with resveratrol inhibited the SNP-induced expression of p53 and p21 and reduced the expression of procaspase-3 in chondrocytes, as detected by western blot analysis. SNP-induced degradation of I-kappa B alpha (IkappaB-alpha) was rescued by resveratrol treatment, and the SN50 peptide-mediated inhibition of NF-kappa B (NF-kappaB) activity potently blocked SNP-induced caspase-3 activation and apoptosis. Our results suggest that resveratrol inhibits NO-induced apoptosis through the NF-kappaB pathway in articular chondrocytes.

Snapshot of degenerative aging of porcine intervertebral disc: a model to unravel the molecular mechanisms

Larger animal models, such as porcine, have been validated as appropriate models of the human disc with respect to biomechanics and biochemistry. They are advantageous for research as the models are relatively straightforward to prepare and easily obtainable for research to perform surgical techniques. The intention of this study was to quantitatively analyze gene expression for collagen and proteoglycan components of the extracellular matrix and for collagenase (MMP-1) in porcine discs of varying ages (Newborn; 2-3weeks, Mature; 6-9 month, Older; 2-3 years). In this study, we observed that the cell number and GAG (glycosaminoglycan) formation dramatically decreased with aging. Also, gene expression in the annulus fibrosus (AF) and nucleus pulposus (NP) cells changed with aging. The level of MMP-1 mRNA increased with age and both type I, II collagens decreased with age. The level of aggrecan mRNA was highest in the mature group and decreased significantly with aging. In the mature group, MMP-1 expression was minimal compared to the newborn group. In AF cells, type II collagen was expressed at a high level in the mature group with a higher level of aggrecan, when aged NP showed a decrease in type II collagen. The model of IVD degeneration in the porcine disc shows many changes in gene expression with age that have been previously documented for human and may serve as a model for studying changes in IVD metabolism with age. We concluded that the porcine model is excellent to test hypotheses related to disc degeneration while permitting time-course study in biologically active systems.