Paeonol, the main active component isolated from the root of Paeonia suffruticosa, has been reported to have anti-inflammatory properties. However, the effects of
paeonol on
osteoarthritis (OA) remain unclear. The aim of this study was to investigate the anti-inflammatory effects and mechanism of
paeonol in IL-1β-induced human OA chondrocytes as well as mice OA models. Human OA chondrocytes were pretreated with different concentrations of
paeonol 2 h prior to IL-1β (10 ng/mL) stimulation for 24 h.
Nitric oxide (NO) production was determined by Griess method. The levels of
prostaglandin E2 (
PGE2),
matrix metalloproteinase 1 (MMP-1), MMP-3, and MMP-13 were assessed by ELISA.
Inducible nitric oxide synthase (INOS), COX-2, and PI3K/Akt/NF-κB-related signaling molecules production were measured by Western blot. In vivo, mice OA models were established by destabilization of the medial meniscus. One month after surgery, mice in
paeonol-treated group were given
intraperitoneal injection of
paeonol in 30 mg/kg every day, while mice of vehicle-treated group were injected with
DMSO under the same conditions.
Hematoxylin and
eosin as well as
Safranin-O staining were applied to assess the severity of cartilage lesions. The results showed that pretreatment with
paeonol could inhibit IL-1β-induced NO and
PGE2 production. Meanwhile, the overproduction of INOS, COX-2, MMP-1, MMP-3, and MMP-13 were also reversed by
paeonol. Moreover,
paeonol was found to inhibit IL-1β-induced NF-κB activation, PI3K, and AKT phosphorylation. In vivo, treatment with
paeonol exhibited less cartilage degradation and lower
Osteoarthritis Research Society International scores in mice OA models. In conclusion, these results suggest that
paeonol may be a potential therapeutic agent in the treatment of OA.