Protective effect of the standardized leaf extract of Ginkgo biloba (EGb761) against hypertension-induced renal injury in rats

ABSTRACT

Background: Ginkgo biloba leaves extract has been widely used worldwide to protect against oxidative stress-induced cell damage and improves blood circulation. Methods: The potential protective role of the standardized leaf extract of Ginkgo biloba (EGb761) on hypertension-induced renal injury was investigated in rats. Hypertension was induced in rats by L-NAME. Result: Repeated treatment with EGb761 produced progressive reductions in the systolic, diastolic and mean arterial blood pressure. Also, EGb761 increased the progressive reductions in blood pressure induced by losartan. Hypertension-induced marked elevation of renal malondialdehyde (MDA) and nitrite levels and reduction of reduced glutathione (GSH) level were inhibited by EGb761. In addition, hypertension-induced increases in tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-1β (IL-1β)) levels in renal tissues were inhibited by EGb761. Also, treatment with EGb761 inhibited hypertension-induced decrease in endothelial nitric oxide synthase (eNOS) protein expression and increase in the protein expressions of inducible NO synthase (iNOS), TNF-α, IL-6 and IL-1B in the kidney tissues. EGb761 enhanced losartan effects on renal tissues oxidative stress, nitrite, and inflammatory markers levels and on protein expressions of eNOS, iNOS, TNF-α, IL-6 and IL-1B. effects. Conclusions:These results indicate that EGb761 has the ability to protect against hypertension-induced renal injury.

KEYWORDS:

• Ginkgo biloba extract
• hypertension
• immunohistochemistry
• losartan
• renal injury

Acknowledgments

This work was funded by the Grant office, Faculty of Medicine, Assiut University.