In vivo and in vitro anti-inflammatory activity of red clover Trifolium pratense dry extract

Red clover Trifolium pratense L., Fabaceae, contains four isoflavones, mainly formononetin and biochanin A, and in smaller concentrations, daidzein and genistein. These compounds have gained a lot interest due to its human health benefits, such as estrogenic and progestogenic activities, antioxidant, anti-cancer and others. The objective of this study was to determine in vivo and in vitro anti-inflammatory activity of red clover dry extract. The in vitro anti-inflammatory activity was assayed by the technique using the Boyden chamber method, evaluating the leukocyte migration inhibition (chemotaxis). The in vivo anti-inflammatory activity was tested by a carrageenan-induced rat paw edema test. The results of anti-inflammatory in vitro test showed that there was a significant inhibition of leukocyte migration at the concentrations of 100, 50, 25, 10 and 5 µg/mL of red clover dry extract, these doses resulted in 94.73, 95.39, 94.73, 84.68 and 78.75% of inhibition for each dose, respectively. The anti-inflammatory in vivo test resulted in a significant activity in both tested doses (100 and 50 mg/kg of red clover dry extract) and at each tested time. The average percentage of edema inhibition was 63.37%. The findings of this study suggested that red clover extract might be suitable for the treatment of inflammatory diseases.