Abstract
Anti-inflammatory effects of Brazilian licorice (Periandra mediterranea or P. dulcis, local name: aracacuz da terra) extract on animal models for inflammatory or autoimmune diseases were examined comparing them to those of Chinese licorice (Glycyrrhiza glabra) extract. Brazilian licorice extracts potently inhibited the elevation of tumor necrosis factor-α and interleukin-6 concentrations, and glutamate-oxaloacetate transaminase activity in the sera of mice treated with P. acnes and lipopolysaccharide. Brazilian licorice extracts apparently inhibited the clinical symptom and bone destruction associated with the induction of arthritis in mice, and the body weight change in mice treated with Brazilian licorice extract was minimal. Brazilian licorice extracts apparently inhibited the clinical symptom and inflammatory cell accumulation in the parenchyma of spinal cord in rats immunized with bovine myelin basic protein. The inhibitory effects of Chinese licorice extract on these disease models were apparently less pronounced than those of Brazilian licorice extract. Furthermore, the IC50 value of Brazilian licorice extract against 11β-hydoxysteroid dehydrogenase activity, one of the metabolizing enzymes for corticosteroids, was more than 3 times of Chinese licorice extract. These results clearly indicate that Brazilian licorice possesses potent anti-inflammatory activities with little adverse effect when compared to Chinese licorice.
