Effects of an aqueous extract of Eucommia on articular cartilage in a rat model of osteoarthritis of the knee

Abstract

Osteoarthritis is a common chronic and progressively degenerative joint condition. The stem bark of Eucommia ulmoides Oliver (a member of the Eucommiaceae family), which is also known as Du-Zhong, is a traditional Chinese medicine commonly used for the treatment of rheumatoid arthritis. However, the mechanisms underlying the effects of Eucommia in the treatment of arthritis of the knee require further study. The present study investigated the effects of an aqueous extract of Eucommia on the articular cartilage (by Mankin’s grade) and the levels of matrix metalloproteinase-1 (MMP-1), MMP-3 and MMP-13 in the serum and synovial fluid in a rat model of osteoarthritis. The serum levels of MMP-1, -3 and -13 were measured by double-antibody sandwich enzyme-linked immunosorbent assay (ELISA) at weeks 1, 2 and 4. The levels of MMP-1, -3 and 13 were significantly decreased in the rats treated with Eucommia compared with those in the control rats (P<0.05). Histopathological examination results indicated a lower Mankin’s grade in the Eucommia group compared with that of the control rats. Therefore, Eucommia was demonstrated to have a cartilage-protecting effect in rats with osteoarthritis, potentially by improving cartilage metabolism, regulating the degradation of the extracellular matrix of the articular cartilage, and inhibiting apoptosis in chondrocytes, thereby slowing down joint degeneration.

Aucubin prevents interleukin-1 beta induced inflammation and cartilage matrix degradation via inhibition of NF-κB signaling pathway in rat articular chondrocytes

“…Recent evidence has shown that Aucubin possesses anti-inflammatory property and inhibits NF-κB activation [22]. Moreover, an interesting study addressing the pharmaceutical effects of Eucommia ulmoides, a native Chinese medicinal herb whose major ingredient is Aucubin, indicates that it can inhibit inflammatory factors and prevents the degradation of the cartilage matrix in rats with OA [25]. Consistent with these reports, the present study confirms the anti-inflammatory and chondro-protective role, as well as the biosafety, of Aucubin at the cellular level.…”

Obesity-associated metabolic syndrome spontaneously induces infiltration of pro-inflammatory macrophage in synovium and promotes osteoarthritis

“…Moreover, in this study, we observed that HCHF synovial fluid, had remarkable effects on both synovial macrophages and chondrocytes, however, an overall profile of cytokines, chemokines and other signalling proteins of the synovial fluid from the two group of animals is required to clearly elucidate the association between the diet-induced obesity and OA. Additionally, we obtained joint synovial fluid sample by a standard lavage procedure [ 78 ]. Nonetheless, it is possible that different concentrations of synovial fluid analytes can be generated by the collection process alone, in addition to any changes due to obesity.…”

Insights into the Action Mechanisms of Traditional Chinese Medicine in Osteoarthritis

“…The results show that a lower Mankin's grade induced by Eucommia is involved in histopathological examination. The levels of MMP-1, MMP-3, and MMP-13 in the serum and synovial fluid are negatively controlled by Eucommia [ 77 ]. These might be associated with downregulation of PI3K/Akt signaling pathway [ 78 ].…”