Effect of Dioscorea villosa extract and the phytoestrogen diosgenin on ovariectomized mice with zymosan-induced arthritis

Abstract Humans are exposed to natural compounds such as phytoestrogens primarily through diet and supplements. These compounds promote health by alleviating the symptoms and illnesses associated with menopause and arthritis. Diosgenin (DSG) occurs naturally in plants such as Dioscorea villosa (DV) and binds to estrogen receptors, so it may have similar effects to this hormone, including against arthritis. Thus, we investigated the effect of chronic treatment with dry extract of DV and its phytoestrogen DSG on ovariectomized mice with arthritis. We found that dry extract of Dioscorea villosa (DV) contains the phytoestrogen diosgenin (DSG) in its composition. Furthermore, arthritic mice treated with DV and DSG showed reduced neutrophil accumulation in the articular cartilage. Also, the dry extract of DV administered orally (v.o) did not alter the leukocyte count in the joints or promote changes in the reproductive tract. However, DSG altered these parameters, with possible beneficial effects by reducing symptoms related to reproductive aging. Thus, oral treatment with dry extract of DV and subcutaneous (s.c) treatment with DSG showed promise by acting against inflammation caused by arthritis and reducing symptoms in the reproductive tract due to menopause.

Expression of glycine receptor α3 subunit in neuropathic and inflammatory central pain sensitization

INTRODUCTION: Increasing evidence suggests that changes in the balance of excitatory/inhibitory neurotransmission are involved in the development of the majority of chronic pain forms. In this context, impairment in glycine mediated inhibitory neurotransmission is thought to play a critical role in the disinhibition that accounts for the development and maintenance of central pain hypersensitivity. AIMS: The goal of this study was to evaluate the Glycine Receptor α3 subunit (α3GlyR) expression in neuropathic (Chronic Constriction Injury, CCI) and inflammatory (Zymosan A injected) animal models of chronic pain. RESULTS AND CONCLUSION: RT-qPCR analysis of spinal cord samples showed that glra3 gene expression does not change after 3 days of CCI and 4 hours of Zymosan A injection. However, we found that protein levels evaluated by Western blot increased after inflammatory pain. These data suggest that central sensitization is differentially regulated depending on the type of pain. α3GlyR protein expression plays an important role in the first step of inflammatory pain establishment.