Scientific basis of botanical medicine as alternative remedies for rheumatoid arthritis

Rheumatoid arthritis (RA) is a chronic, systemic autoimmune inflammatory disorder that causes permanent disability and mortality to approximately 1 to 100 people in the world. Patients with RA not only suffer from pain, stiffness, swelling, and loss of function in their joints, but also have a higher risk of cardiovascular disease and lymphoma. Typically prescribed medications, including pain-relieving drugs, nonsteroidal anti-inflammatory drugs (NSAID), and disease-modifying antirheumatic drugs, can help to relieve pain, reduce inflammation and slow the course of disease progression in RA patients. However, the general effectiveness of the drugs has been far from satisfactory. Other therapeutic modalities like TNF-alpha (TNF-α) inhibitors and interleukin-1 receptor antagonists targeting precise pathways within the immune system are expensive and may be associated with serious side effects. Recently, botanical medicines have become popular as alternative remedies as they are believed to be efficacious, safe and have over a thousand years experience in treating patients. In this review, we will summarize recent evidence for pharmacological effects of herbs including Black cohosh, Angelica sinensis, Licorice, Tripterygium wilfordii, Centella asiatica, and Urtica dioica. Scientific research has demonstrated that these herbs have strong anti-inflammatory and anti-arthritic effects. A wide range of phytochemicals including phenolic acids, phenylpropanoid ester, triterpene glycosides, phthalide, flavonoids, triterpenoid saponin, diterpene and triterpene have been isolated and demonstrated to be responsible for the biological effects of the herbs. Understanding the mechanisms of action of the herbs may provide new treatment opportunities for RA patients.