Inhibitory effects of Acanthopanax sessiliflorus Harms extract on the etiology of rheumatoid arthritis in a collagen-induced arthritis mouse model.

BACKGROUND: The biological function of Acanthopanax sessiliflorus Harm (ASH) has been investigated on various diseases; however, the effects of ASH on arthritis have not been investigated so far. This study investigates the effects of ASH on rheumatoid arthritis (RA). METHODS: Supercritical carbon dioxide (CO2) was used for ASH extract preparation, and its primary components, pimaric and kaurenoic acids, were identified using gas chromatography-mass spectrometer (GC-MS). Collagenase-induced arthritis (CIA) was used as the RA model, and primary cultures of articular chondrocytes were used to examine the inhibitory effects of ASH extract on arthritis in three synovial joints: ankle, sole, and knee. RESULTS: Pimaric and kaurenoic acids attenuated pro-inflammatory cytokine-mediated increase in the catabolic factors and retrieved pro-inflammatory cytokine-mediated decrease in related anabolic factors in vitro; however, they did not affect pro-inflammatory cytokine (IL-1ß, TNF-α, and IL-6)-mediated cytotoxicity. ASH effectively inhibited cartilage degradation in the knee, ankle, and toe in the CIA model and decreased pannus development in the knee. Immunohistochemistry demonstrated that ASH mostly inhibited the IL-6-mediated matrix metalloproteinase. Gene Ontology and pathway studies bridge major gaps in the literature and provide insights into the pathophysiology and in-depth mechanisms of RA-like joint degeneration. CONCLUSIONS: To the best of our knowledge, this is the first study to conduct extensive research on the efficacy of ASH extract in inhibiting the pathogenesis of RA. However, additional animal models and clinical studies are required to validate this hypothesis.

Inhibitory effects of Ganoderma lucidum spore oil on rheumatoid arthritis in a collagen-induced arthritis mouse model.

Holistic healthcare practitioners have now started to focus on specific traditional medicinal mushrooms to treat rheumatoid arthritis (RA). Ganoderma lucidum (GL) is one of the oldest mushrooms that have been used in ancient Chinese medicine to treat inflammatory ailments, including autoimmune diseases such as RA. Spores from this mushroom have specific effects on immunomodulation, aging, and cancer. However, the effect of G. lucidum spores (GLS) on arthritis remains unclear. Therefore, we investigated the effects of GLS oil in a collagen-induced rheumatoid arthritis (CIA) model. Metabolomics analysis revealed that GLS oil contains ten acids, of which oleic acid (52.12%) and linoleic acid (16.77%) predominated. The GLS oil-treated CIA mice had a significantly lower clinical score (p = 0.0384) for RA than the control CIA mice. Moreover, GLS oil reduced CIA-induced cartilage degeneration and synovial membrane inflammation in the knee. The GLS oil group showed significantly reduced knee eosinophilia (p = 0.0056). Immunostaining of neutrophils revealed that neutrophils infiltrated the CIA group; however, infiltrated neutrophils were significantly reduced in the GLS oil group in both the knees (p = 0.0006) and ankles (p = 0.0023). GLS oil treatment substantially suppressed LPS- or TNF-α-induced IL-6 mRNA expression in primary cultured chondrocytes. IL-6 immunohistochemistry results showed that the protein levels of IL-6 were attenuated in the GLS oil group compared to the CIA group. These findings suggest that GLS oil may be useful for the development of RA drugs. Further clinical research is required to identify significant improvements.

GSK5182, 4-Hydroxytamoxifen Analog, a New Potential Therapeutic Drug for Osteoarthritis.

Estrogen-related receptors (ERRs) are the first identified orphan nuclear receptors. The ERR family consists of ERRα, ERRß, and ERRγ, regulating diverse isoform-specific functions. We have reported the importance of ERRγ in osteoarthritis (OA) pathogenesis. However, therapeutic approaches with ERRγ against OA associated with inflammatory mechanisms remain limited. Herein, we examined the therapeutic potential of a small-molecule ERRγ inverse agonist, GSK5182 (4-hydroxytamoxifen analog), in OA, to assess the relationship between ERRγ expression and pro-inflammatory cytokines in mouse articular chondrocyte cultures. ERRγ expression increased following chondrocyte exposure to various pro-inflammatory cytokines, including interleukin (IL)-1ß, IL-6, and tumor necrosis factor (TNF)-α. Pro-inflammatory cytokines dose-dependently increased ERRγ protein levels. In mouse articular chondrocytes, adenovirus-mediated ERRγ overexpression upregulated matrix metalloproteinase (MMP)-3 and MMP-13, which participate in cartilage destruction during OA. Adenovirus-mediated ERRγ overexpression in mouse knee joints or ERRγ transgenic mice resulted in OA. In mouse joint tissues, genetic ablation of Esrrg obscured experimental OA. These results indicate that ERRγ is involved in OA pathogenesis. In mouse articular chondrocytes, GSK5182 inhibited pro-inflammatory cytokine-induced catabolic factors. Consistent with the in vitro results, GSK5182 significantly reduced cartilage degeneration in ERRγ-overexpressing mice administered intra-articular Ad-Esrrg. Overall, the ERRγ inverse agonist GSK5182 represents a promising therapeutic small molecule for OA.