Abstract:

To explore the effect of flavonoids from flowers of Paulownia tomentosa on the ultrastructure of spleen and thymus in mice, 120 Kunming mice were randomly divided into four groups (n = 30, half male and half female). Using daily intragastric administration of flavonoids from Paulownia tomentosa flower according to the weight to establish the experimental animal model: Mice in flavonoid group Ⅰ, flavonoid group Ⅱ and flavonoid group Ⅲ were drenched (once daily for 28 days) with 40, 120 and 360 mg·(kg·d)^－1 flavonoid, respectively. Mice in control group were gavaged with equal volume PBS containing 0.5% CMC-Na. On the 28^th day of the treatment, spleens and thymuses were collected and organ index was calculated. Proliferation and transformation of spleen lymphocytes induced by ConA were determined by MTT method. Phagocytosis of peritoneal macrophages was tested by neutral red test. The ultrastructure of spleen and thymuses were observed through scanning electron microscope. The results showed that different doses of flavonoids from Paulownia tomentosa flowers can significantly improve the thymus and spleen index and lymphocyte proliferation response (P<0.05) in a dose-dependent manner. Compared with the control group, the number of mature lymphocytes in mice spleen and thymus increased significantly in the three flavonoid-treated groups, especially in high dose group. The results suggest that flavonoids from Paulownia tomentosa flowers affect the ultrastructure of spleen and thymus by increasing immune organ quality, immune organs mature lymphocyte number. In addition, lymphocyte proliferation response, flavonoids from Paulownia tomentosa flowers has a certain regulation effect on the immune function in mice by reinforcing the T lymphocyte proliferation response of spleen and thymus to the cellular immune function.