Anti-inflammatory and anti-nociceptive activities of Alpinia Oxyphylla Miquel extracts in animal models

Ethnopharmacological relevance: Alpinia Oxyphylla Miquel is a widely used traditional herbal medicine for the treatment of abdominal pain, intestinal disorders, enuresis, and inflammatory conditions. Aim of the study: In this study we aimed to demonstrate the anti-inflammatory and anti-nociceptive effects of Alpinia Oxyphylla Miquel extracts with 50% ethanol (AOE) in animal models. Material and method: The anti-inflammatory and nociceptive effects of AOE were estimated in vivo using a carrageenan-induced rat paw edema model, an arachidonic acid-induced mice ear edema model, an acetic acid induced mice writhing test model, and an ex vivo sulfated glycosaminoglycan (GAG) inhibition assay. In vitro inhibition assays for cyclooxygenase (COX) and lipoxygenase (LOX) were performed to determine the IC50 of AOE. Results: Compared with the control, AOE caused a significant inhibition of paw edema, ear thickness, and abdominal constriction in animals. Compared with untreated explants exposed to interleukin-l alpha (IL-1 alpha), preoteoglycan degradation by IL-1 alpha was inhibited (18.2%-82.0%) in explants treated with AOE (50-400 mu g/ml). In vitro, IC50 values of AOE were 299.87, 199.07, and 170.29 mu g/ml for COX-1, COX-2, and 5-LOX respectively. Conclusions: These data demonstrate the potent anti-inflammatory and analgesic effects of AOE and suggest AOE to be useful for the treatment of osteoarthritis and/or associated symptoms.