Résumé
Aim To explore the protective effect of Zishen Huoxue Prescription on OGD/R-induced primary hippocampal neuron damage in rats and the possible mechanism. Methods After the isolated primary hippocampal neurons were identified by immunofluorescence, OGD/R induced neuronal damage, and the changes of autophagic flux at different re-oxygenation time were observed by confocal laser scanning microscopy. After OGD/R-induced primary hippocampal neurons were intervened with serum containing Zishen Huoxue Prescription, cell viability was detected by CCK-8, cell apoptosis was detected by flow cytometry, autophagosomes were detected by transmission electron microscopy, and autophagy-related protein expressions were detected by Western blot. Results 10% Zishen Huoxue Prescription-containing serum could significantly improve cell viability and reduce the proportion of cell apoptosis, increase the number of autophagosomes in neurons, and up-regulate the expression of autophagy-related protein PINK1, Parkin, and pATG16L1. Conclusions Zishen Huoxue Prescription can effectively resist OGD/R-induced apoptosis of primary hippocampal neurons in rats, and its effect may be related to the regulation of PINK1-Parkin pathway to promote mitophagy.
Résumé
ObjectiveTo investigate the effect of Zishen Huoxue prescription on promoting neurogenesis in hippocampal CA1 region of vascular dementia （VD） rats by regulating mitophagy. MethodThe 2-VO method was used to establish the VD rat model and 60 SD rats were randomly divided into sham operation group， model group， donepezil hydrochloride group， and Zishen Huoxue prescription low-dose（8.9 g·kg-1）， medium-dose（17.8 g·kg-1） and high-dose（35.6 g·kg-1） groups. Morris water maze test was performed to detect the escape latency and the number of crossing platform in each group. The expression of phosphatase and tensin homology-induced kinase 1 （PINK1） and Parkinson protein （Parkin） mRNA in hippocampal CA1 region was detected by Real-time fluorescent quantitative polymerase chain reaction（Real-time PCR）. Western blot was used to determine the expression of mitochondrial autophagy signaling pathway-related proteins Parkin， prohibitin 2 （PHB2）， mitofusin 2 （Mfn2） and dynamin-related protein 1 （Drp1） in hippocampal CA1 region. The neurogenesis in hippocampal CA1 region was tested by Brdu method. ResultCompared with the conditions in the sham operation group， the learning and spatial memory abilities of the model group were decreased （P<0.05）， with damaged mitochondrial structure and autolysosome formation in the hippocampal CA1 region. The expressions of Parkin， Pink1 mRNA and Parkin， PHB2， and Drp1 proteins were up-regulated （P<0.05）， while the expression of Mfn2 protein and the neuronal regeneration in hippocampal CA1 region were reduced （P<0.05， P<0.05）. Compared with the conditions in the model group， Zishen Huoxue prescription enhanced the learning and spatial memory abilities of VD rats （P<0.05）， increased the number of autophagosomes in hippocampal CA1 region and improved the mitochondrial structure. The expression of Parkin， Pink1 mRNA and Parkin， PHB2， and Drp1 proteins in hippocampal CA1 region was up-regulated （P<0.05， P<0.01）while the expression of Mfn2 protein was down-regulated（P<0.05， P<0.01）. The number of new neurons in hippocampal CA1 region was also increased（P<0.05， P<0.01）. ConclusionThe promoting effect of Zishen Huoxue prescription on the neurogenesis in hippocampal CA1 region of VD rats was related to the mitophagy mediated by Pink1/Parkin signaling pathway.