Anmeidan Improves Learning and Memory Ability of Sleep-deprived Rats by Regulating Astrocyte Activity / 中国实验方剂学杂志

ObjectiveTo explore the effect of Anmeidan （AMD） on the learning and memory ability of sleep-deprived rats and the mechanism. MethodA total of 50 SD rats were randomized into control group， model group， low-dose AMD group （4.55 g·kg-1·d-1）， high-dose AMD group （18.18 g·kg-1·d-1）， and estazolam group （0.09 mg·kg-1·d-1）. Insomnia was induced in rats with the self-made sleep deprivation box （21 days）. The learning and memory ability of rats was measured by Morris water maze. Immunofluorescence method was employed to detect the number of cells expressing N-myc downstream-regulated gene 2 （NDRG2） and glial fibrillary acidic protein （GFAP） in hippocampus of rats， real-time fluorescent quantitative polymerase chain reaction （Real-time PCR） to determine the mRNA expression of hippocampal NDRG2， glial glutamate transporter-1 （GLT-1）， and GluNR2A and GluNR2B N-methyl-D-aspartate （NMDA） receptor subunits， and Western blot to examine the protein expression of NDRG2 and GLT-1 in hippocampus. ResultCompared with control group， the model group showed increase in the latency to reach the platform and total swimming distance， significant decrease in the total distance moved in the target quadrant， time in target quadrant， and times of crossing the platform （P<0.01）， rise in the number of cells expressing NDRG2 and GFAP in the hippocampal CA1 region （P<0.01） and the mRNA level of NDRG2 and GluNR2B， reduction in the mRNA level of GLT-1 and GluNR2A， elevation in NDRG2 protein expression （P<0.01）， and decrease in GLT-1 protein expression （P<0.01）. In contrast to the model group， low-dose and high-dose AMD improved the learning and memory levels of sleep-deprived rats （P<0.01）， reduced the number of cells expressing NDRG2 and GFAP （P<0.01）， significantly decreased the mRNA expression of NDRG2 and GluNR2B， increased the mRNA expression of GLT-1 and GluNR2A， reduced NDRG2 protein level （P<0.05， P<0.01）， and raised GLT-1 protein level （P<0.01）. ConclusionAMD can improve the learning and memory ability of sleep-deprived rats. The mechanism is the likelihood that it regulates astrocyte activity， thereby affecting the neurotransmitter level and synaptic plasticity in the brain.

Effects of puerarin on H2O2-induced SH-SY5Y cell apoptosis / 中国药理学通报

Aim To investigate the neuroprotective effects of puerarin on H2O2-induced SH-SY5Y cell ap-optosis and the molecular mechanisms underlying the neuroprotective effects. Methods Neuron injury mod-el was established in vitro through H2O2-induced SH-SY5Y injury. MTT assay was performed to detect the effect of puerarin on H2O2-induced SH-SY5Y survival rates. Hoechst 33342 staining was used to observe the cell apoptosis. JC-1 staining was employed to detect the level of mitochondria membrane poential. Caspase-3 was determined by caspase-3 catalyze the substrate specificity Ac-DEVD-pNA. Caspase-9 was determined by caspase-9 catalyze the substrate specificity Ac-LE-HD-pNA. The effects of puerarin on the protein level of Bcl-2,Bax,p-Akt and Akt were determined by West-ern blot. Results The cell survival rate significantly increased after puerarin pretreatment compared with H2O2model group. Furthermore, puerarin pretreat-ment not only inhibited the decreasing of mitochondrial membrane potential,increasing of caspase-3, caspase-9 enzymatic activity and the expression of Bax,but also promoted the expression of p-Akt and Bcl-2, which was prevented by LY294002, an inhibitor of PI3K/Akt. Conclusion Puerarin can play a neuroprotective role for SH-SY5Y cell apoptosis induced by H2O2, maybe via activating PI3K/Akt signaling pathway.