| Phytochemical | Source | Model used | In vivo/in vitro activity | Structure |
| Epigallocatechin-3-gallate (EGCG) | Green tea (Camellia sinensis) | Cocktail of monoclonal antibodies against collagen [5], AA model [6] In vitro | Clinical score, histology ↓ [5], histology, radiology, TNF-α, IL-6 ↓ [6]; iNOS, nitric oxide, MMP-1 and MMP-13, glycosaminoglycan, osteoclastogenesis ↓ NF-κB, c-Fos, NFATc ↓ [7] | |
| Curcumin | Turmeric (Curcuma longa) | CIA rat model In vitro | Clinical score, TNF-α, IL-1β, NF-κB ↓; iNOS, PGE2, COX-2, IL-6, IL-8, MMP-3, MMP-9 ↓ [8] PGE2, COX-2, MMP, NF-κB ↓ [9] | |
| Celastrol | Celastrus species |
AA rat model In vitro
| TNF-α, IL-1β, IL-6, IL-17, IL-18 ↓ [10, 11], RANKL, osteoclast ↓ [11] STAT3, MMP-9, pERK ↓ [12], NF-κB, IκB-α kinase, p-IκB-α, p-p65 ↓ [13, 14], p-JNK, p-c-Jun and NF-κB ↓ [15], AKT/mTOR [16], angiogenesis ↓ [16, 17] | |
| Resveratol | Grapes (Vitis vinifera) | CIA model In vitro
| Clinical score, IL-17, IL-1 ↓ [18] ROS, PGE2, MMPs ↓ in vitro. Proteoglycan synthesis and chondrocyte proliferation ↑ [19] | |
| Rosmarinic acid | Plectranthus amboinicus | CIA model In vitro | TRAP, pit formation ↓ [20] NFATc1 ↓ [20] | |
| Boswellic acid, AKBA | Boswellia plants | BSA-induced arthritis in rabbits, carrageenan- induced edema In vitro
| Leukocyte infiltration ↓ [21, 22] Phosphorylation of ERK-1/2 ↓ [23], STAT3 ↓ [24], NF-κB ↓ [25], angiogenesis ↓ [26] | |
| Genistein | Lupin, fava beans, soybeans, and coffee | Rat CIA model | IFN-γ ↓, IL-4 ↑ [27], ERK, MAPK ↓ [28] | |
| Lupeol | Calatropis gigantean | Rat AA model | TNF-α, IL-1β, IL-6 ↓ [29] | |
| 6-Shogaol | Ginger (Zingiber officinale) | CFA-induced monoarthritic model of the knee joint of rats In vitro
| Infiltration of leukocytes, cartilage protection [30] MMP-9, NF-κB, IκB phosphorylation ↓ [31] | |
| Naringin | Citrus fruits | Rat CIA model | Clinical score ↓, histology [32] | |
|
Hesperidin | Citrus fruits | Rat CIA model | Clinical score ↓, histology [33] | |
| Capsaicin | Capsicum | Osteoarthritis in rat In vitro
|
Bone erosion and trabecular damage ↓ [34] MMP-9, FAK/Akt, PKC/Raf/ERK, p38 (MAPK), AP-1 ↓ [35]
| |
| Ferulic acid | Coffee, apple, rice |
Ovariectomy-induced rats | Bone remodeling ↑ [36] | |
| Oleuropein aglycone | Olive oil | Mouse CIA model | Histological damage ↓ [37] | |
| Quercetin | Onion | Overiectomy-induced rats In vitro
| Osteoclast differentiation, osteoclast-related genes ↓ [38] MMP-1, 3, COX-2, PGE2 phosphorylation of ERK-1/2, p38, JNK, NF-κB ↓ [39] | |
| Silibinin | Silymarin |
In vitro RAW 264.7 cells, MC3T3 cells
|
Osteoclasts, OSCAR, NFATc1, Cat K, MMP-9, RANKL ↓ [9], ERK 1/2 and c-Jun phosphorylation ↓ [40]
| |
| Total flavonoid of orange (TFO) | Orange | Rat AA model | TNF-α, IL-1β, PGE2 and COX2 ↓ [41] | |
| Highly oligomeric procyanidins (HOPCs) | Jatoba | Mouse CIA model | Clinical score, joint histology ↓ [42] | |
| Green tea polyphenol (GTP) | Green tea (Camellia sinensis) | CIA, AA model | COX-2, TNF-α, IFN-γ ↓ [43], clinical score, IL-17 ↓, IL-10 ↑ [44] | |
| Proanthocyanidin | Grape seeds | Mouse CIA model | Clinical score, IL-17, IL-21, IL-22 ↓, Foxp3 ↑ [45] | |
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