Grant: Master's Award: Canada Graduate Scholarships

Cartilage is composed of specialized cells called chondrocytes. Cartilage acts as a template on which the majority of bones in our body are formed. This specialized process by which bones develop on a cartilage template is called endochondral ossification. The exact mechanism through which growth and development of cartilage is controlled is largely unknown. Our preliminary animal and cell based studies suggest that a biological factor called PPARgamma is involved in cartilage growth and development and may influence the formation of bones. To test the role of PPARgamma in cartilage growth and development and in the formation of bones, we generated animals in which PPARgamma is genetically absent only in cartilage. Using these mice we will be able to specifically understand and answer the following questions: (1)Does PPARgamma control growth and development of cartilage? (2)Does PPARgamma control formation and growth of bones? (3)Does PPARgamma control survival of chondrocytes? Thus far, my results show that those animals, which lack PPARgamma have reduced body size and reduced body weight. They also have reduced skeletal size and reduced length of long bones compared to normal control mice. The levels of biological markers that are involved in cartilage growth are reduced in the cells of the mice in which PPARgamma is absent. Furthermore, the levels of biological markers that are involved in the degradation of cartilage are higher in the cells of the mice in which PPARgamma is absent. All of these results collectively suggest a potential role of PPARgamma in growth and development of cartilage. This project has the potential to generate new therapeutic strategies for the treatment of growth-related disorders and diseases such as osteoarthritis and osteoporosis.