Resveratrol suppresses angiogenesis in gliomas: Evaluation by color Doppler ultrasound

Background: The effects of resveratrol (a natural polyphenol) on angiogenesis in rat gliomas were investigated by color Doppler ultrasound (CDUS). The correlation among the tumor growth rate, macroscopic angiogenesis measured by CDUS and microscopic angiogenesis was assessed by immunohistochemical staining. Materials and Methods: Fischer rats were subcutaneously inoculated with rat RT-2 glioma cells and treated with resveratrol for 4 weeks. The tumor size was measured and the animal survival followed. CDUS examination was used to measure tumor blood flow shown as the color Doppler vascularity index (CDVI). Immunohistochemical staining of CD31 was carried out to assess the microvessel density (MVD) of the tumors. The CDVI, MVD and tumor size were correlated. Results: Rats treated with resveratrol (40 mg/kg/day) had slower tumor growth rates than those of the control groups (p<0.05). The CDVI, MVD and tumor size were significantly correlated (linear regression, p<0.0001). Conclusion: Resveratrol-suppressed glioma growth was significantly correlated with the inhibition of macroscopic and microscopic angiogenesis.