Ginsenoside Rg1 inhibits β-secretase activity in vitro and protects against Aβ-induced cytotoxicity in PC12 cells

Abstract

Ginsenoside Rg1 (1) is a major active component of Panax notoginseng, a Chinese herb widely used in traditional Chinese medicine to improve learning and memory function. Increasing evidence suggests that β-amyloid peptide (Aβ) plays a central role in the pathophysiology of Alzheimer's disease (AD). To elucidate the mechanism of 1 on improving the ability of learning and memory, we investigated whether 1 could affect Aβ generation or protect Aβ-induced neurotoxicity. The results showed that 1 could inhibit β-secretase activity in vitro and also protect the PC12 cells against injuries caused by exposure of PC12 cells to 50 μM Aβ_25-35 for 48 h. The cell death, LDH release, NO release, ROS production, lipid peroxidation, intracellular calcium elevation, and apoptosis are associated events induced by Aβ that can be rescued by 1 in PC12 cells. In conclusion, 1 may be a promising agent for AD, and the mechanism is related to β-secretase inhibition and protection against Aβ-induced cytotoxicity.

Keywords:

• ginsenoside Rg1
• β-secretase
• β-amyloid peptide

Acknowledgements

The present study was supported by the project (No. 30630073) from the National Natural Science Foundation of China and the project (No. 2006QN40) from the Young Foundation of Institute of Materia Medica, Chinese Academy of Medical Sciences.