Crocin Attenuates Joint Pain and Muscle Dysfunction in Osteoarthritis Rat.

Osteoarthritis is the most prevalent form of arthritis, affecting a large part of population. It has been reported that muscle weakness and inflammation contribute to osteoarthritis development and progression. Oxidative stress plays important roles in muscle dysfunction and inflammation induction. Crocin, a component of saffron, has excellent antioxidative property. However, it is unclear if crocin can be a potential medicine for osteoarthritis therapy. Osteoarthritis in rats was induced by meniscectomy (MNX) surgery. Then, rats were given with 30 mg/kg of crocin daily for 10 days after osteoarthritis induction. The parameters were determined 7 days after crocin administration. MNX surgery induced osteoarthritis in rats. Crocin treatment significantly decreased osteoarthritis-associated joint pain, decreased muscular interleukin-6 (IL-6) level, and increased citrate synthase (CS) activity, as well as myosin heavy chain (MHC) IIα expression. In addition, crocin reduced muscular lipid peroxidation (LPO) and Nrf2 expression and increased glutathione production and glutathione peroxidase activity. Finally, crocin inhibited the activity of JNK, but not ERK, to repress NF-κB activation and inflammation induction. Crocin attenuates osteoarthritis symptoms through alleviating oxidative stress and inflammation, suggesting that crocin is a potential medicine for osteoarthritis therapy.