TABLE 1.

Brief summary of studies on crocin and OA.

Reference	Models/Crocin doses	Main results	Conclusion
Lei et al. (2017)	Rats/30 mg/kg daily for 10 days	Decrease in joint pain, IL-6 level, LPO, and Nrf2 expression; increase in CS activity, MHC IIα expression, glutathione production, and glutathione peroxidase activity	Crocin reduces OA symptoms by affecting oxidative stress, inflammation, and JNK activity
Ding et al. (2013)	chondrocyte culture, and 5–100 µM (50–1,000 mg/ml) intra-articular injection	Repression of IL-1ß, downregulation of mRNA and protein expression of MMP-1, -3 and -13	Crocin reduces inflammation in-vitro and regenerates rabbit knee cartilage
(K. Li et al., 2015 )	NP cells/10–100 µM (100–1,000 mg/ml)	Decrease MMP-1, -3, and -13 overexpression, IL-1β, TNF-α, IL-6, and iNOS, and inhibit MAPK and JNK pathways	Crocin reduces inflammation in-vitro and ex-vivo
Poursamimi et al. (2020)	OA patients/15 mg tabs/day for 4 months	Decrease CRP and IL-17, increase regulatory T cells, shifted Treg/Th17 ratio towards regulatory T cells	Crocin decreases inflammation in OA patients