Eucommia ulmoides Oliv. and Its Active Components: A Comprehensive Review of their Role and Mechanisms in the Treatment of Rheumatoid Arthritis

Abstract

Eucommia ulmoides Oliv., a traditional Chinese medicinal herb, has long been used to strengthen bones, tonify the liver and kidneys, and alleviate inflammation-induced bone damage, particularly in rheumatoid arthritis (RA). Modern pharmacological studies have confirmed its anti-inflammatory, antioxidant, and antiosteoclastic properties, as well as its ability to inhibit synovial hyperplasia and angiogenesis, key pathological processes in RA progression. This review synthesizes existing knowledge on the bioactive components of E. ulmoides Oliv. and their underlying mechanisms of action, aiming to establish a scientific basis for its clinical application in RA therapy. E. ulmoides Oliv. is a safe, edible plant with high nutritional value, containing a variety of bioactive compounds, including lignans, iridoids, flavonoids, and phenolic acids. These constituents collectively contribute to its anti-RA effects by targeting multiple pathological pathways. Specifically, E. ulmoides Oliv. extracts inhibit vascular endothelial growth factor expression, thereby reducing synovial angiogenesis and hyperplasia. They also modulate critical inflammatory pathways such as nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK), downregulating the expression of proinflammatory cytokines. In addition, E. ulmoides Oliv.-derived components suppress osteoclast activity, preventing bone erosion and protecting joint integrity. Emerging research suggests that E. ulmoides Oliv. may also influence RA pathogenesis through the modulation of gut microbiome composition. Pharmacokinetic studies have identified 24 E. ulmoides Oliv.-derived compounds with potential for anti-RA drug development. In summary, E. ulmoides Oliv. offers a multifaceted approach to RA treatment, simultaneously addressing inflammation, synovial proliferation, and bone destruction. These findings bridge the gap between the traditional medicinal use of E. ulmoides Oliv. and modern scientific evidence, positioning E. ulmoides Oliv. as a promising candidate for integrative RA management. Future research should focus on well-designed clinical trials to assess its efficacy and safety, optimize dosing regimens, and explore potential synergies with conventional RA therapies.