Effect of isorhapontigenin on respiratory burst of rat neutrophils.

The effect of Isorhapontigenin (Iso) isolated from Belamcanda chinensis on respiratory burst of rat neutrophils was investigated. Iso (1, 10, 100 mmol/l) showed an inhibitory effect on superoxide anion and hydrogen peroxide production in phorbol myristate acetate (PMA) activated rat neutrophils in a concentration-dependent manner. Scanning electron microscopy detected that Iso (100 mmol/l) protected against surface changes in rat neutrophils stimulated with PMA. Also, 100 mmol/l Iso inhibited the release of beta-glucuronidase from the activated neutrophils. Electron-spin resonance (ESR) detected that Iso scavenged oxygen free radicals generated in the PMA activated Neutrophils. These results suggest that Iso inhibits respiratory burst of PMA-activated rat neutrophils by scavenging oxygen free radicals.