MMP13 and osteoarthritis: In a study by Simopoulu et al. [18] of cartilage culture samples obtained from patients with primary osteoarthritis, reverse transcription polymerase chain reaction (RT-PCR) and Western blot analysis were used to evaluate the effects of 2-day administration of 50 μM statin on the production of inflammatory cytokines and proteolytic enzymes and it was reported that this agent had reduced the production of IL-1 and blocked the transcription of MMP-13 mRNA.