Chondrocytes articular cartilage

The latter issue was addressed more recently by Hamilton et al. who developed a trilayer composite consisting of CPP, articular cartilage (CEP), and NP tissue [125]. By sequential seeding of chondrocytes onto the CPP surface followed 2 weeks later by seeding NP cells onto the matrix produced by the chondrocytes, the authors were able to form a tissue composite construct. Although it appeared that the NP cells were able to maintain a rounded morphology, the interfacial shear load required to... 

Collier S, Ghosh R Comparison of the effects of NSAIDs on proteoglycan synthesis by articular cartilage explant and chondrocyte monolayer cultures. Biochem Pharmacol. 1991 41 1375-1384. 

Isolated chondrocytes grown in type I and type II collagen-glycosaminoglycan matrices contract the matrix and immunochemically stain for alpha-smooth muscle actin. These results suggest that chondrocytes can also generate active tension and may be responsible for maintaining the tension in articular cartilage. 

Figure 9.6. Diagram illustrating the pretension present in the superficial zone of articular cartilage. Normal articular cartilage shown at the top is loaded in tension across the surface like a drumhead that is pulled taut over a drum. When a piece of cartilage is cut from the surface, it curls as a result of release of this tension, as shown in the lower diagram. The presence of tension in the superficial zone makes articular cartilage behave like a drumhead, allowing compressive forces applied to the surface at specific points to be distributed across the surface to lower local stresses. The presence of tension on the chondrocytes in the superficial layer may be important to limit inflammation and support reparative processes by stimulating mechanochemical transduction.

Loening AM, James IE, Levenston ME, Badger AM, Frank EH, Kurz B, Nuttall ME, Hung H-H, Blake SM, Grodzinsky AJ, Lark MW. Injurious mechanical compression of bovine articular cartilage indices chondrocyte apoptosis. Arch Biochem Biophys. 2000 381 205-212. 

The potential beneficial and detrimental effects of MPA on articular cartilage and chondrocytes... 

The growth plate chondrocytes undergo proliferation, growth, degradation, mineralization, and resorption and provide the support structure for new bone formation. Bones can increase in length and width through this process. Endochondral ossification occurs near the base of the articular cartilage at the joints. 

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