Protective effects of aqueous extract of arctium lappa root on vascular endothelial cell injury of hypertensive rats.

Objective To study the protective effects and mechanism of aqueous extract of arctium lappa root on vascular endothelial cell injury in hypertensive rats. Methods The hypertensive rat model was induced by N-nitro-L-argi-nine. Rats were randomly divided into normal control group, model control group, positive control group (aptopril 15 mg/kg), low concentration of aqueous extract of arctium lappa root (0.5 g/kg), medium concentration of (1 g/kg) and high concentration of (2 g/kg) groups. After six weeks of continuous intragastric administration, the systolic blood pressure levels at tail artery were measured at 1, 4, 7, 10, 13, 16, 19, 22, 29, 36 and 42 d after treatment. And other indicators related to inflammatory factors were detected including C-reactive protein (CRP) and interleukin (IL)-6. The intercellular adhesion molecule-1 (ICAM-1) level was detected by taking samples of thoracic aorta. Results (1) The systolic blood pressure level at tail artery was significantly lower in aqueous extract of arctium lappa root group than that of model control group (P<0.05). (2) The aqueous extract of arctium lappa root can significantly improve the vascular endothelial cell injury, suppress vascular endothelial cell loss and blood cell adhesion, and cell proliferation with collagen fibers in muscle membrane. (3) The serum levels of IL-6, CRP and vascular endothelial ICAM-1 were significantly reduced in aqueous extract of arctium lappa root group than that of model control group (P<0.05). Conclusion Aqueous extract of arctium lappa root can significantly improve vascular endothelial cell injury in hypertensive rats. The mechanism may be related to the inhibition of inflammatory cytokines like IL-6, CRP and the expression of ICAM-1, and the improvement of chronic inflammatory response in vascular endothelium of hypertensive rats. [ABSTRACT FROM AUTHOR]