Neuroprotective effect of lyophilized powder of catalpol and puerarin on oxygen-glucose deprivation/reperfusion injury in astrocytes of rat cerebral cortex in vitro / 中国药学杂志

ABSTRACT

OBJECTIVE: To investigate the protection of lyophilized powder of catalpol and puerarin (C-P) on oxygen-glucose deprivation/reperfusion(OGD/R)-injured astrocytes and the possible mechanism in vitro. METHODS: Primary astrocytes were isolated from the cerebral cortex of neonatal rats. The purity of astrocytes was identified by GFAP immunofluorescence. Astrocytes were divided into 6 groups normal group, model group, excipients group, and three groups with gradient doses of C-P (12.25, 24.50, 49.00 μg·mL-1). After astrocytes suffered from OGD/R (OGD 6 h/R 12 h) with or without C-P, cell survival, LDH leakage, and apoptosis were analyzed by MTT, colorimetry, and TUNEL respectively. The apoptotic protein, caspase-3, was evaluated by Western blot. Meanwhile, oxidative indexes including SOD, GSH, ROS, MDA, and NO were detected by assay kits. In terms of inflammation, TNF-α, IL-1β, and PGE2 in medium were evaluated via ELISA. iNOS, COX-2, NF-κB p65, p-NF-κB p65, IκB-α, and p-IκB-α were examined by Western blot. RESULTS: The purity of primary astrocytes was more than 97%. Compared with normal group, the cell survival rate of model group decreased significantly, while the LDH leakage rate and cell apoptosis rate markedly increased after OGD/R injury in model group. Meanwhile, SOD activity and GSH level in astrocytes markedly decreased. The level of MDA and ROS significantly increased. The content of NO, TNF-α, IL-1β, and PGE2 released in medium also sharply increased. However, those changes of related biochemical indexes above could be reversed by different gradient doses of C-P. There was no significant difference between excipients group and model group. Further study found that C-P could inhibit the protein expression of caspase-3, iNOS, and COX-2, as well as the increase of phosphorylation level of NF-κB p65 and IκB-α significantly. CONCLUSION: C-P shows a protective effect on the OGD/R injured astrocytes in vitro, and its protection mechanism involves in anti-inflammation, antioxidant, inhibiting the cell apoptosis and activation of NF-κB signaling pathway.