Neuroprotective effect of a caffeic acid derivative from Abacopteris penangiana.

CONTEXT

A new caffeic acid derivative, named (7'Z)-3-O-(3, 4-dihydroxyphenylethenyl)-caffeic acid (CADP), extracted from Abacopteris penangiana (Hook.) Ching.

OBJECTIVE

To elucidate the neuroprotective effect of CADP against H₂O₂-induced cytotoxicity in PC12 cells and D-galactose (D-gal)-induced neurotoxicity in mice brain.

MATERIALS AND METHODS

CADP was isolated from the methanol extract of the rhizomes of A. penangiana. In vitro, the protective effect of CADP (0.1-10 μM) against H₂O₂-induced oxidative damage on PC12 cells was investigated by a MTT assay. In vivo, behavioral tests and antioxidant enzymes measurements were performed to investigate the protective effect of intraperitoneal (i.p.) injection of CADP (5 or 10 mg/kg/day) for 2 weeks on D-gal-induced neurotoxicity in mice.

RESULTS

The results showed that CADP significantly attenuated cell toxicity in a dose-dependent manner, and the EC₅₀ value of CADP was 0.83 ± 0.02 μM. In vivo, it was found that CADP significantly improved the behavioral performance of D-gal-treated mice in both Morris water maze (MWM) test and step-down avoidance test. As compared with model group, CADP (5, 10 mg/kg/day) attenuated the decrease in superoxide dismutase (SOD) activities by 40.5 and 75.4%, respectively; attenuated the decrease in glutathione peroxidase (GPx) activities by 53.8 and 73.2%, respectively; attenuated the decrease in catalase activities by 12.0 and 53.3%, respectively; reduced the increased levels of malondialdehyde (MDA) by 38.6 and 79.9%, respectively.

DISCUSSION AND CONCLUSION

The results suggested that CADP has significant neuroprotective effects which can be attributed to inhibiting the generation of free radical and enhancing the activity of endogenous antioxidant enzymes.