Figure 4: Relative expression of mTOR, ULK1, p21, caspase 3 (a), COL10A1, MMP-13, and MMP-9 (b) genes compared between healthy cartilages ( , set 1) and osteoarthritic cartilages ( , set 1) as determined by real-time PCR analyses with reference to β -actin. Controls are shown as 1.0 as required for relative quantification with the real-time PCR protocol. Asterisks ( ) indicate significant differences from the control (Student’s unpaired -test).