Can active components of licorice, glycyrrhizin and glycyrrhetinic acid, lick rheumatoid arthritis?
OBJECTIVE
This review stated the possible application of the active components of licorice, glycyrrhizin (GL) and glycyrrhetinic acid (GA), in rheumatoid arthritis (RA) treatment based on the cyclooxygenase (COX)-2/thromboxane A2 (TxA2) pathway.


METHODS
The extensive literature from inception to July 2015 was searched in PubMed central, and relevant reports were identified according to the purpose of this study.


RESULTS
The active components of licorice GL and GA exert the potential anti-inflammatory effects through, at least in part, suppressing COX-2 and its downstream product TxA2. Additionally, the COX-2/TxA2 pathway, an auto-regulatory feedback loop, has been recently found to be a crucial mechanism underlying the pathogenesis of RA. However, TxA2 is neither the pharmacological target of non-steroidal anti-inflammatory drugs (NSAIDs) nor the target of disease modifying anti-rheumatic drugs (DMARDs), and the limitations and side effects of those drugs may be, at least in part, attributable to lack of the effects on the COX-2/TxA2 pathway. Therefore, GL and GA capable of targeting this pathway hold the potential as a novel add-on therapy in therapeutic strategy, which is supported by several bench experiments.


CONCLUSIONS
The active components of licorice, GL and GA, could not only potentiate the therapeutic effects but also decrease the adverse effects of NSAIDs or DMARDs through suppressing the COX-2/TxA2 pathway during treatment course of RA.
Department of Rheumatology, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Qing-Chun
QC
Huang
Central Laboratory, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Mao-Jie
MJ
Wang
Department of Rheumatology, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Xiu-Min
XM
Chen
Central Laboratory, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Wan-Lin
WL
Yu
Department of Rheumatology, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Yong-Liang
YL
Chu
Department of Rheumatology, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Xiao-Hong
XH
He
Department of Rheumatology, The Second Affiliated Hospital, Guangzhou University of Chinese Medicine (Guangdong Provincial Hospital of Chinese Medicine), Guangzhou, China.
Run-Yue
RY
Huang
D018501:Antirheumatic Agents / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000188:drug therapy* / Q000378:metabolism; D051546:Cyclooxygenase 2 / Q000378:metabolism; D006034:Glycyrrhetinic Acid / Q000627:therapeutic use*; D006035:Glycyrrhiza / Q000737:chemistry*; D019695:Glycyrrhizic Acid / Q000627:therapeutic use*; D006801:Humans; D008517:Phytotherapy / Q000379:methods; D013928:Thromboxane A2 / Q000378:metabolism; D016896:Treatment Outcome
D018501:Antirheumatic Agents; D013928:Thromboxane A2; D019695:Glycyrrhizic Acid; D051546:Cyclooxygenase 2; D006034:Glycyrrhetinic Acid
glycyrrhetinic acid; glycyrrhizin; licorice; rheumatoid arthritis; the COX-2/TxA2 pathway