CNS neuroscience & therapeutics

Compound MQA, a Caffeoylquinic Acid Derivative, Protects Against NMDA-Induced Neurotoxicity and Potential Mechanisms In Vitro.

PMID 26096046


Compound MQA (1,5-O-dicaffeoyl-3-O-[4-malic acid methyl ester]-quinic acid) is a natural derivative of caffeoylquinic acid isolated from Arctium lappa L. roots. However, we know little about the effects of MQA on the central nervous system. This study aims to investigate the neuroprotective effects and underlying mechanisms of MQA against the neurotoxicity of N-methyl-d-aspartate (NMDA). Pretreatment with MQA attenuated the loss of cell viability after SH-SY5Y cells treated with 1 mM NMDA for 30 min by MTT assay. Hoechst 33342 and Annexin V-PI double staining showed that MQA inhibited NMDA-induced apoptosis. In addition to preventing Ca(2+) influx, the potential mechanisms are associated with increases in the Bcl-2/Bax ratio, attenuation of cytochrome c release, caspase-3, caspase-9 activities, and expressions. Also, MQA inhibited NMDA-induced phosphorylation of ERK1/2, p38, and JNK1/2. Furthermore, deactivation of CREB, AKT, and GSK-3β, upregulation of GluN2B-containing NMDA receptors (NMDARs), and downregulation of GluN2A-containing NMDARs were significantly reversed by MQA treatment. Computational docking simulation indicates that MQA possesses a well affinity for NMDARs. The protective effects of MQA against NMDA-induced cell injury may be mediated by blocking NMDARs. The potential mechanisms are related with mitochondrial apoptosis, ERK-CREB, AKT/GSK-3β, p38, and JNK1/2 pathway.