IL13 and tendinitis: In order to investigate the in vivo anti-inflammatory effects of SIM/PMSs on collagenase-induced Achilles tendinitis models, we monitored the mRNA levels of both pro-inflammatory cytokines (MMP-3, COX-2, IL-6, TNF-α, and MMP-13) and anti-inflammatory cytokines (IL-4, IL-10, and IL-13).