Effects of Harmine Inducing Apoptosis on Mitochondrial Fusion and Division in PC 12 Cells / 医药导报

Objective To investigate the effects of harmine(HM)on the expression level of mitochondrion fusion related proteins and mitochondrial function injury in PC 12 cells.Methods PC 12 cells were divided into cell control group,HM group,mitochondrion mitosis inhibitor Mdivi-1 group,HM+Mdivi-1 group,mitochondrion fission agonist WY14643 group,HM+WY14643 group,with drug concentrations of 1,10,25,50,100 μmol·L-1.After 24 h treatment,the MTT method was used to detect the cell survival rate,and a microscope was used to observe the cell morphology,MitoTracker Red probe staining was used to observe the mitochondrial morphology and the length ratio of vertical and horizontal axes,JC-1 staining was used to detect the mitochondrial membrane potential,and a kit was used to detect ATP level and lactate dehydrogenase(LDH)activity.Immunofluorescence staining and Western blotting were used to assess the expression levels of caspase-3,apoptosis-promoting protein(Bax)cytochrome C(cyt-c),mitochondrial fusion protein(Mfn2)and mitochondrial mitotic protein(Drp-1).The interference sequence of Drp1 was transfected by electroporation,and the siRNA sequence with good transfection effect was screened.The related indicators were detected by fluorescence method,MTT method,and immunoblotting method in cooperation with drug intervention.Results MTT results showed that compared with the cell control group,the survival rate of HM group,Mdivi-1 group,HM+Mdivi-1 group,WY14643 group and HM+WY14643 group decreased significantly(P＜0.01),and the EC50 were(11.48±2.32),(12.35±1.67),(14.88±2.07),(39.14±3.25),(20.09±1.97),respectively.According to this,subsequent experiments selected 20 μmol·L-1for HM,WY 14643 and HM+WY14643 as working concentrations to construct PC 12 cell model.Microscopic observation and MitoTracker Red probe staining showed that the cell density in the drug group decreased in varying degrees,and a transition from branched to round morphology in the drug-treated groups was observed.The morphology of mitochondria tended to be round,and the ratio of the length of the longitudinal axis to transverse axis was(3.33±0.72)in the cell control group,(2.19±0.58)in the HM group,(2.45±0.44)in Mdivi-1 group,and(1.43±0.62)in HM+Mdivi-1 group,respectively.The results of JC-1 staining showed that compared with the cell control group,the mitochondrial mode potential of the HM group significantly decreased(P＜0.01).ROS significantly increased(P＜0.01)and ATP levels decreased(P＜0.01),and LDH enzyme activity increased(P＜0.01).Immunofluorescence staining and Western blotting results showed that compared with the cell control group,the expression levels of proapoptotic proteins Bax,cytochrome C,and caspase-3 in the HM group were significantly increased(all P＜0.01).Compared with the cell control group,the expression level of mitochondrial fission related protein Drp1 in HM group was significantly higher(P＜0.01).The expression level of mitochondrial fusion related protein Mfn2 significantly decreased(P＜0.01).After specific interference with Drp1 and synergistic intervention with HM,the survival rate of PC 12 cells in each interference group decreased compared to each drug intervention group.The expression of Drp1 and Mfn2 was downregulated,and the differences were statistically significant(P＜0.05 or P＜0.01).Conclusion HM can reduce the mitochoudrial membrane potential and ATP levels by accumulating ROS,there by activating the caspase-3 apoptosis pathway and promoting cell apoptosis.Mitochondrial fusion division may be involved in the damage of PC12 cells caused by HM,initiating apoptosis through the mitochondrial pathway.

Adipose-derived mesenchymal stem cell-derived exosomes alleviate hydrogen peroxide-induced PC12 cell apoptosis / 中国组织工程研究

BACKGROUND:Mesenchymal stem cell-derived exosomes may play a crucial role in tissue damage repair,and miRNA is an important component of exosomes for therapeutic effects.Among them,miR-29b-3p has the effect of reducing cell apoptosis,promoting axonal regeneration,and angiogenesis. OBJECTIVE:To study the protective effect of adipose-derived mesenchymal stem cell-derived exosome via miR-29b-3p on a neural cell injury model simulated by H2O2-treated PC12 cells,and explore the relevant mechanisms. METHODS:(1)First,the collagenase digestion method was used to extract rat adipose-derived mesenchymal stem cells.Adipose-derived mesenchymal stem cells were transfected with miR-29b-3p mimics and inhibitors.Exosomes were extracted from the culture supernatant by ultracentrifugation and identified so as to construct adipose-derived mesenchymal stem cell-derived exosomes with high expression and knockdown miR-29b-3p.(2)By constructing a neural cell injury model simulated by PC12 cells treated with H2O2,the relevant mechanisms of the protective effect of adipose-derived mesenchymal stem cell-derived exosome via miR-29b-3p on the simulated neuronal cell injury model were studied. RESULTS AND CONCLUSION:(1)Adipose-derived mesenchymal stem cell-derived exosome had a typical cup-shaped shape and a diameter distribution in the range of 50-140 nm,expressed membrane proteins Alix,CD63,and TSG101,which were specific markers on the surface of exosomes,and could be successfully ingested by PC12 cells.(2)Adipose-derived mesenchymal stem cell-derived exosome pretreatment could reduce cell apoptosis induced by H2O2 treatment in PC12 cells,and this protective effect was enhanced with the increase of miR-29b-3p expression in the exosomes and weakened with the decrease of miR-29b-3p expression in the exosomes.The mechanism of its effect was related to adipose-derived mesenchymal stem cell-derived exosome via miR-29b-3p promoting the expression of anti-apoptotic protein Bcl-2 and inhibiting the expression of apoptotic protein Bax.

Effects of tricholoma matsutake polysaccharides on 1-methy-4-pehnyl-pyridine ion-induced PC12 cell damage / 解剖学报

Obｊective To investigate the protective mechanism of tricholoma matsutake polysaccharides(TMP) against 1-methy-4-pehnyl-pyridine ion (MPP

Effects of latroeggtoxin-VI on dopamine and α-synuclein in PC12 cells and the implications for Parkinson's disease

Background Parkinson's disease (PD) is characterized by death of dopaminergic neurons leading to dopamine deficiency, excessive α-synuclein facilitating Lewy body formation, etc. Latroeggtoxin-VI (LETX-VI), a proteinaceous neurotoxin discovered from the eggs of spider L. tredecimguttatus, was previously found to promote the synthesis and release of PC12 cells, showing a great potential as a drug candidate for PD. However, the relevant mechanisms have not been understood completely. The present study explored the mechanism underlying the effects of LETX-VI on dopamine and α-synuclein of PC12 cells and the implications for PD. Results After PC12 cells were treated with LETX-VI, the level of dopamine was significantly increased in a dose-dependent way within a certain range of concentrations. Further mechanism analysis showed that LETX-VI upregulated the expression of tyrosine hydroxylase (TH) and L-dopa decarboxylase to enhance the biosynthesis of dopamine, and downregulated that of monoamine oxidase B to reduce the degradation of dopamine. At the same time, LETX-VI promoted the transport and release of dopamine through modulating the abundance and/or posttranslational modification of vesicular monoamine transporter 2 (VMAT2) and dopamine transporter (DAT). While the level of dopamine was increased by LETX-VI treatment, α-synuclein content was reduced by the spider toxin. α-Synuclein overexpression significantly decreased the dopamine level and LETX-VI efficiently alleviated the inhibitory action of excessive α-synuclein on dopamine. In the MPTP-induced mouse model of PD, application of LETX-VI ameliorated parkinsonian behaviors of the mice, and reduced the magnitude of MPTP-induced α-synuclein upregulation and TH downregulation. In addition, LETX-VI displayed neuroprotective effects by inhibiting MPTP-induced decrease in the numbers of TH-positive and Nissl-stained neurons in mouse brain tissues. Conclusions All the results demonstrate that LETX-VI promotes the synthesis and release of dopamine in PC12 cells via multiple mechanisms including preventing abnormal α-synuclein accumulation, showing implications in the prevention and treatment of PD.

Effect of bergapten on glucose and oxygen deprivation induced PC12 cell injury by regulating long non-coding RNA opioid receptor gene expression / 解剖学报

Objective To study whether bergapten (BG) protects PC12 cells from oxygen-glucose deprivation (OGD) induced cell injury by regulating long non-coding RNA (lncRNA) opioid receptor gene (Oprm1) expression. Methods PC12 cells were divided into control (Con) group, OGD group, OGD+ low concentration BG (BG-L) group, OGD+medium concentration BG (BG-M) group, OGD + high concentration BG (BG-H) group, OGD + pcDNA group, OGD+pcDNA-Oprm1 group, OGD+BG+si-NC group, OGD+BG+si-Oprm1 group. The malondialdehyde (MDA) content, superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities were measured by the kits. Cell apoptosis rate was analysed by flow cytometry. The expression level of Oprm1 was analysed by Real-time PCR. Results Compared with the Con group, the apoptosis rate and MDA content of PC12 cells in OGD group increased significantly, whereas Oprm1 expression, SOD and GSH-Px activity decreased significantly (P < 0. 05). Compared with the OGD group, the apoptosis rate and MDA content of PC12 cells in the OGD + BG-L group, OGD + BG-M group, OGD + BG-H group were significantly reduced, whereas the Oprm1 expression, SOD and GSH-Px activities increased significantly (P < 0. 05). Compared with the OGD+pcDNA group, the apoptosis rate and MDA content of the PC12 cells in the OGD+pcDNA-Oprm1 group reduced significantly, whereas the SOD and GSH-Px activities increased significantly (P<0. 05). Compared with the OGD+BG+si-NC group, the apoptosis rate and MDA content of PC12 cells in the OGD+BG+si-Oprm1 group increased significantly, whereas the SOD and GSH-Px activities decreased significantly (P < 0. 05). Conclusion Bergapten may alleviate OGD-induced PC12 cell injury, which is correlated to the up-regulation of lncRNA Oprm1 expression.

Comparison of PC-12 cells’ apoptosis induced by triazine herbicides atrazine, simazine and cyanazine / 西安交通大学学报(医学版)

【Objective】 To compare PC-12 cells’ apoptosis caused by the serotonin herbicides atrazine （ATR）， simazine （SIM） and cyanazine （CYA）. 【Methods】 The rat adrenal medullary pheochromoma PC-12 cell line was selected for routine culture. At the cell logarithmic growth phase， ATR， SIM and CYA were used at a concentration of 200 μmol/L for 24 h， respectively， and the same solvent was added in the control group. The CCK-8 method was used to detect the cell survival rate； the content of reactive oxygen species （ROS） in PC-12 cells was detected； the Real-time PCR and Western blotting methods were used to detect the mRNA and protein expressions of Bax， p53， Bcl-2 and Caspase-3. 【Results】 Compared with that in the control group， the survival rate of the cells in ATR group， SIM group and CYA group was significantly decreased. The intracellular ROS activity of the three groups was significantly increased， and the mRNA and protein expressions of Bax， p53 and Caspase-3 were increased. mRNA and protein expressions of Bcl-2 were significantly reduced （P<0.01）. Compared with that in ATR group， the cell survival rate of SIM group and CYA group was significantly increased， the intracellular ROS activity of the two groups was significantly decreased， the expressions of Bax， p53 and Caspase-3 mRNA and protein were significantly reduced， and the expressions of Bcl-2 mRNA and protein were significantly increased （P<0.01）. Compared with that of SIM group， the cell survival rate of CYA group was significantly increased， while the intracellular ROS activity was significantly decreased； the Bax， p53 and Caspase-3 mRNA and protein expressions were significantly reduced， and Bcl-2 mRNA and protein expressions were significantly increased （P<0.01）. 【Conclusion】 ATR， SIM and CYA can all promote PC-12 cells’ apoptosis； ATR has the strongest effect while CYA has the weakest effect.

MicroRNA-486 targeting TRIM10 to inhibit Parkinson’s disease cell model damage / 解剖学报

[Abstract] Objective To study the effect and mechanism of microRNA-486 (miR-486) on 1-methyl-4-phenylpyridine (MPP

Baicalein reduces Aβ25-35-induced PC12 cell damage by inhibiting the JAK2/STAT1 pathway / 药学学报

This study investigated the mechanism by which baicalein protected PC12 cells from Aβ25-35-induced injury. PC12 cells were treated with Aβ25-35 (20 μmol·L-1) and the ability of baicalein to prevent apoptosis was investigated by monitoring changes in cell morphology, Hoechst 33342 staining, and measurement of inflammatory factors. Western blotting was used to detect the expression of the apoptosis-related proteins cysteinyl aspartate specific proteinase-3 (caspase-3), cleaved cysteinyl aspartate specific proteinase-3 (cleaved caspase-3), proteins involved in the Janus kinase 2/signal transducer and activator of transcription 1 (JAK2/STAT1) pathway, and downstream inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). The results show that baicalein (80 μmol·L-1) can significantly inhibit apoptosis and the release of inflammatory factor IL-8 and TNF-α in Aβ25-35-treated PC12 cells. Western blotting results showed that baicalein can inhibit the phosphorylation of JAK2 and STAT1 and decrease the expression of downstream iNOS and COX-2, thereby inhibiting the JAK2/STAT1 signaling pathway and preventing Aβ25-35-induced PC12 cell damage.

Protective effect of α-asarone and β-asarone on Aβ -induced inflammatory response in PC12 cells and its / 浙江大学学报·医学版

To investigate effects of α-asarone and β-asarone on induced PC12 cell injury and related mechanisms. Aβ toxic injury cell model was induced by Aβ in PC12 cells. PC12 cells were divided into blank control group, model control group, α-asarone group (0.5, 1.0, β-asarone group (6.3, 12.5, vasoactive intestinal peptide (VIP) group, and VIP antagonist control group. Cell survival rate was detected by CCK-8 kit; cell apoptosis rate was detected by flow cytometry. The levels of inflammatory cytokines interleukin (IL)-1, , tumor necrosis factor (TNF)-α, oxidation-related inducible nitric oxide synthase (iNOS), nitric oxide (NO), apoptosis factors caspase-3 and p53 were detected by ELISA method. The expressions of C-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinase (p38MAPK) were detected by Western blotting. Compared with model control group, cell survival rates of group, β-asarone group and VIP group increased; the cell apoptosis rate decreased; levels of apoptosis-related factors caspase-3, p53, inflammatory factors IL-1, TNF-α decreased; IL-10 level increased; levels of oxidization-related factors iNOS and NO decreased; the expression of JNK and p38MAPK protein decreased (all 0.05). α-asarone and β-asarone have protective effects on PC12 cell injury induced by Aβ. β-asarone may inhibit inflammatory factors and oxidation-related factors through promoting VIP secretion, regulating JNK/MAPK pathway, and reducing PC12 cell apoptosis; however, the effect of α-asarone may be not related to VIP secretion.

Protective effect of fluoxetine against hypoxia induced injury on PC12 cells / 中国药理学通报

Aim To study the protective effect of fluoxetine against hypoxia induced injury on PC12 cells. Methods PC12 cells were randomly divided into control group, hypoxia group, and fluoxetine hydrochloride group. The last two groups were put into a hypoxic culture chamber for 18 hours, the cell state was observed under inverted microscope, and cell viability was detected using CCK-8 assay. Reactive oxygen species (ROS) level was evaluated by DCFH-DA. Lactate dehydrogenase (LDH), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) in cell culture supernatant were evaluated by enzyme labeling method. The expression levels of Bcl-2, Bax and caspase-3 were determined by Western blot. Results Compared with normal group, hypoxia caused obvious damage to PC12 cells. Fluoxetine hydrochloride at 10

Amphetamine causing damage of dopamine cells via inhibiting of protein kinase B / glycogen synthase kinase-3β/ collapsin response mediator protein-2 signal pathway / 解剖学报

Objective To explore the damage mechanism of dopamine cells induced by amphetamine (AMPH). Methods The damage model of dopaminergic cells in mice was established by intraperitoneal injection of AMPH. The mice were randomly grouped into control, saline, amphetamine treatment for 1 day, 7 days, 14 days and 28 days. Each group contained 10 mice. The model of cell injury was established by use of AMPH in PC12 cells. The dopaminergic fibers of corpus striatum and PC12 cells were observed by the immunohistochemistry and immunofluorescence method, and changes of proteins in the protein kinase B (Akt) / glycogen synthase kinase 3β(GSK-3β) / collapsin response mediator protein 2 (CRMP-2) signal pathway were detected by Western blotting. Results AMPH caused the damage of dopaminergic fibers in the mouse corpus striatum and PC12 cells. Meanwhile, AMPH inhibited Akt and GSK-3β phosphorylation levels, and increased phosphorylated CRMP-2 level. Nerve growth factor(NGF), an agonist of Akt, or SB216763, an inhibitor of GSK-3β protected PC12 cells against AMPH-induced toxicity through upregulation of Aat and GSK-3β phosphorylation and downregulated of phosphorylation CRMP-2. Conclusion AMPH causes damage of dopamine cells via inhibition of Akt/ GSK-3β/ CRMP-2 signal pathway.

Effect of ligustilide on oxygen and glucose deprivation/reperfusion-induced mitochondria fission in PC12 cells / 中国中药杂志

This study aimed to investigate the effect and mechanism of ligustilide, the main active ingredient in Ligusticum wallichii, on mitochondria fission after PC12 cell injury induced by oxygen and glucose deprivation/reperfusion(OGD/R). In the experiment, an OGD/R model was established in vitro, and PC12 cells were pre-treated with ligustilide for 3 h, and then the cell viability was detected by CCK-8 method. The effect of different concentrations of ligustilide on the morphology of PC12 cells after OGD/R injury was observed under an inverted microscope. Transmission electron microscopy was used to observe the mitochondrial fission of PC12 cells after OGD/R injury. DCFH-DA immunofluorescence staining method was used to detect intracellular reactive oxygen species(ROS) changes. Changes in mitochondria membrane potential(MMP) were detected by flow cytometry. Hochest 33258 was used to observe the apoptosis of PC12 cells. Western blot was used to detect changes in cytochrome C(Cyt C) content in mitochondria and cytoplasm, and mitochondrial fission-related proteins Drp 1 and Fis 1. All results showed that compared with the model group, ligustilide significantly increased the survival rate of PC12 cells and the number of cells. Further experiments showed that ligustilide inhibited the release of ROS and decline of mitochondrial membrane potential in PC12 cells after OGD/R injury. Moreover, ligustilide reduced the release of Cyt C and promoted the expressions of Drp1 and Fis1 in mitochondrial fission proteins. Verification experiments showed that mitochondrial fission inhibitor mdivi-1 decreased cell survival rate and inhibited fission. The results indicated that ligustilide exerted neuro-protective effects by promoting mitochondrial fission and reducing cell damage. It preliminary proves that the mechanism of ligustilide on ischemic brain injury may be related to the promotion of mitochondrial fission and the maintenance of cell homeostasis.

Study on the Protective Effects of Butein on Oxidative Stress Injury of PC 12 Cell and Its Effects on Mitochondrial Function / 中国药房

OBJECTIVE：To study the protective effects of butein on oxidative stress injury of PC12 cell and its effects on mitochondrial function. METHODS：Rats PC12 cells were divided into normal control group，model group，solvent control group（1 ‰ dimethyl sulfoxide），butein high，medium and low concentration groups（2，1，0.5 μmol/L）. The latter 4 groups were given relevant reagent/medicine for intervention；24 h later，other groups were given 100 mU/mL glucose oxidase to induce oxidant stress model except for normal control group. After 4 h culture，cell survival rate，apoptosis rate，the levels or activities of ROS，MDA，SOD，CAT，GSH-Px，ATP，IL-1β and TNF-α as well as the change of MMP were detected. RESULTS：Compared with normal control group，cell survival rate，the levels or activities of SOD，CAT，GSH-Px and ATP were all decreased significantly，and apoptotic rate，the content of ROS，the levels of MDA，IL-1β and TNF-α were all increased significantly（P＜0.05 or P＜0.01），while the MMP was decreased significantly. Compared with model group，above indexes of solvent control group had no significant change （P＞0.05），cell survival rates，the levels or activities of SOD （except for medium and low concentration groups），CAT，GSH-Px（except for medium and low concentration groups），ATP（except for low concentration group）were increased significantly in butein high，medium and low concentration groups，while apoptotic rates，the content of ROS，the levels of MDA，IL-1 β and TNF-α were decreased significantly（P＜0.05 or P＜0.01），while the MMP were increased significantly. CONCLUSIONS：Butein can increase the antioxidant enzyme activity， stabilize mitochondrial function， inhibit oxidative stress and inflammationthus， increase energy generation inhibiting neuronal cell apoptosis ultimately exerting a neuroprotective effect.

Effects of calycosin on mitochondrial apoptotic pathway in oxygen-glucose deprivation / reoxygenation PC12 cells / 解剖学报

Objective To investigate the effect of calycosin on mitochondrial apoptotic pathway in oxygen-glucose deprivation/ reoxygenation PC12 cells. Methods PC12 cells were randomly divided into four groups: control group, model group, calycosin group and nimodipine group. Except for the control group, the other groups were treated with oxygen and glucose deprivation for 2 hours and compound oxygen and glucose for 24 hours. Calycosin group and nimodipine group were treated with drug-containing medium containing calycosin (0. 07 μmol/ L) and nimodipine (5. 00 μmol/ L) simultaneously with reoxygenation. CCK-8 method was used to detect cell survival rate, flow cytometry was used to detect cell apoptosis rate, immunofluorescence method was used to detect Bax/ Bcl-2 ratio, Western blotting was used to detect the expression of key proteins cytochrome C (Cyt-C), apoptotic protease activating factor-1 (Apaf-1) and Caspase-3 in mitochondrial apoptotic pathway. Results Compared with the control group, the survival rate of cells in model group decreased significantly (P<0. 05), and the apoptotic rate increased significantly (P<0. 05), the ratio of Bax/ Bcl-2 was significantly increased (P<0. 05), and the expression of key proteins Cyt-C, Apaf-1 and Caspase-3 in mitochondrial apoptotic pathway were significantly increased (P<0. 05). Compared with the model group, the cell survival rates of calycosin group and nimodipine group increased significantly (P < 0. 05), apoptotic rate decreased significantly (P<0. 05), the ratio of Bax/ Bcl-2 was significantly decreased (P<0. 05), and the expression of key proteins of mitochondrial apoptotic pathway, Cyt-C, Apaf-1 and Caspase-3 were significantly decreased (P < 0. 05). The difference has statistical significance. Conclusion Calycosin can significantly improve the survival rate of oxygen-glucose deprivation/ reoxygenation PC12 cells and inhibit cell apoptosis. Its mechanism is closely related to the inhibition of the expression of key proteins Cyt-C, Apaf-1 and Caspase-3 in mitochondrial apoptotic pathway by calycosin.

Effects of puerarin on the expressions of CaM, CaMKⅡ, MECP2, BDNF and Akt in oxygen and glucose deprivation cell models / 西安交通大学学报(医学版)

Objective: To observe the effects of puerarin on the expressions of CaM, CaMKⅡ, BDNF and Akt in vascular dementia cell models induced by oxygen and glucose deprivation (OGD). Methods: The passaged well-differentiated PC12 cells were randomly divided into control group, model group, and low-dose, medium-dose and high-dose intervention groups. Vascular dementia cell model was established by OGD. Suitable OGD time and concentration of puererin were obtained from the cell viability measured by MTT assay. The release of LDH was measured to assess the extent of cell damage and identify cell models. The expressions of CaM, CaMKⅡ, MECP2, BDNF and Akt were detected by Western blot. Results: PC12 cells with OGD prolonged viability decreased in a time-dependent manner, with increased concentrations of puerarin increased in a concentration-dependent manner. Effective intervention of puerarin was 0.1-10 μmol/L and optimal time of OGD was 6 h. Compared with control group, the release of LDH in model group was significantly increased (P0.05). Puerarin could down-regulate the level of CaM protein, increase the expressions of MECP2 and BDNF and the phosphorylation of CaMKⅡ, and also increase the phosphorylation of Akt in addition to the low-dose group (P<0.05). Conclusion: The neuroprotective effect of puerarin may be related to the increase of the autophosphorylation of CaMKⅡ mediated by Ca2+-CaM complex, induce the phosphorylation of MECP2, up-regulate the expression of BDNF and activate the PI3K-Akt pathway to inhibit the expression of apoptotic genes and proteins.

Protective Effect and Mechanism of Tetramethylpyrazine Against t-BHP-induced PC12 Cell Injury / 中国实验方剂学杂志

Objective:To study the protective effect of tetramethylpyrazine (TMP) on PC12 cells induced by tert-butyl hydroperoxide (t-BHP) and the regulatory mechanism on signaling pathway of phosphatidylinositol-3-kinases (PI3K)/kinase B (Akt)/mammalian target of rapamycin(mTOR). Method:PC12 cells cultured in vitro were treated with t-BHP (200 μmol·L-1) for 6 h to establish a model of oxidative damage in PC12 cells. The experiment was divided into blank group, model group (200 μmol·L-1t-BHP), TMP group. PC12 cells were pretreated with TMP(25, 50, 100 μmol·L-1) for 12 h, and then treated with t-BHP for 6 h. The cell viability was detected by cell counting kit-8(CCK-8) method, and lactate dehydrogenase (LDH) leakage, malondialdehyde (MDA) content, superoxide dismutase (SOD) activity, reactive oxygen species (ROS) and glutathione peroxidase (GSH-Px) activity were detected by enzyme-linked immunosorbent assay (ELISA). Apoptosis was observed by annexin V-FITC/PI double staining. B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), total protein kinase B (Akt), and phosphorylated protein kinase B (p-Akt), mTOR and p-mTOR expressions were detected by Western blot. Result:The cell viability of PC12 cells treated with 200 μmol·L-1 t-BHP decreased to about 50%after 6 h. This condition was suitable for the establishment of oxidative damage model. Compared with the model group, TMP (25, 50, 100 μmol·L-1) pretreatment for 12 h significantly increased the survival rate of PC12 cells (PPPPPPP-1) pretreatment group increased significantly (PConclusion:Ligustrazine protects PC12 cell injury induced by t-BHP by activating PI3K/Akt/mTOR signaling pathway.

Effect of microenvironment on β-site amyloid precursor protein cleaving enzyme 1 expression in PC12 Cells / 上海交通大学学报（医学版）

Objective • To investigate the effect of microenvironment on the expression of β-site amyloid precursor protein cleaving enzyme 1 (BACE1) in PC12 cells. Methods • The PC12 cells were respectively treated with thapsigargin (Tg), lipopolysaccharide (LPS), H2O2, hypoxia incubator and hypoglycemic medium to produce mild endoplasmic reticulum stress (ERS), inflammatory environment, mild oxidative stress, hypoxia and low glucose conditions. Western blotting and fluorescence quantitative PCR were used to detect the expression of BACE1 protein and BACE1 mRNA. Results • After PC12 cells were treated with Tg (0.13 μmol/L) for 12 h or LPS (0.01 mg/mL) for 36 h, BACE1 protein and mRNA levels were significantly up-regulated (P0.05). Conclusion • Mild ERS and inflammatory condition can up-regulate BACE1 mRNA and protein expression in PC12 cells.

Protective effects of genistein on Aβ₂₅₋₃₅-induced PC12 cell injury via regulating CaM-CaMKIV signaling pathway / 中国中药杂志

Genistein is a kind of isoflavone compounds， also called phytoestrogens， with clinical effects on cardiovascular disease， cancer and postmenopausal-related gynecological diseases， and also has the potentiality in the prevention and treatment of Alzheimer's disease(AD). In this study， the protective effect of genistein on Aβ₂₅₋₃₅-induced PC12 cell injury and effect on CaM-CaMKIV signaling pathway were observed to investigate its mechanism for AD. PC12 cells were cultured and then the safe concentration of genistein and the modeling concentration and optimal time point of administration of Aβ₂₅₋₃₅ were screened by MTT assay. After being pretreated with different concentrations of genistein(25， 50， 100 μmol·L⁻¹) on PC12 cells， the AD model of PC12 cells was induced by Aβ₂₅₋₃₅. Then the survival rate of cells was detected by MTT assay; morphological change of cells was observed under the inverted microscope， and apoptosis of cells was assessed by AO/EB fluorescence staining; the neuroprotective effects of genistein on AD cell model were observed and the optimal concentration of genistein was determined. Expressions of mRNA and protein levels of CaM， CaMKK， CaMKIV and tau were detected by qRT-PCR and Western blot assay， respectively. The results showed that as compared with the blank group， the cell survival rate was decreased; the cell damage and apoptosis were increased; and the expressions of mRNA and protein levels of CaM， CaMKK， CaMKIV and tau were increased in AD model group. Genistein could significantly improve the cell survival rate， reduce the cell damage and apoptosis of AD cell model， and significantly down-regulate the expressions of mRNA and protein levels of CaM， CaMKK， CaMKIV and tau of AD cell model. These results indicated that genistein has obviously neuroprotective effect on the AD cell model induced by Aβ₂₅₋₃₅， and the mechanism may be related to the down-regulation of CaM-CaMKIV signaling pathway and Tau protein expression.

Protective effect of water soluble CoQ10 on rotenone-induced apoptosis in PC12 cells / 西安交通大学学报(医学版)

Objective To investigate the protective effect and the underlying mechanism of water soluble coenzyme Q10 (CoQ10)against rotenone induced injury on PC12 cells model.Methods PC12 cells were cultured with rotenone,water-soluble CoQ1 0 was added to the culture media 3 hours prior to the rotenone incubation.We determined cell viability by CCK8;reactive oxygen species (ROS)was detected by spectrophotometer;and Bcl-2, Bax,active Caspase-3,Caspase-9 and apoptosis-inducing factor (AIF)were measured by Western blotting after 24-hour rotenone incubation.Results After the treatment by rotenone,cell viability decreased significantly (P＜0.01)and ROS level increased (P＜0.01).CoQ10 could improve PC12 cell viability (P＜0.01)and reduce the level of ROS (P＜0.01).Western blotting experiments showed that CoQ10 could reduce rotenone-induced Caspase-9 (P＜0.05),active Caspase-3 (P＜0.05)and Bax (P＜0.01)expressions,increase the expression of Bcl-2 (P＜0.01),and prevent nuclear translocation of AIF (P＜0.05).Conclusion CoQ10 has a protective effect on rotenone-induced apoptosis in PC12 cells,the mechanism of which may be through scavenging ROS in cells;decreasing caspase-9 ,active caspase-3 and Bax expressions;and increasing the expression of Bcl-2 ;and preventing AIF nuclear translocation.

Preparation of DJ-1 overexpressing cell model by using lentiviral vector / 基础医学与临床

Objective To prepare gene overexpressing cell model of human wild-type DJ-1 and its L166P mutant, and to investigate the role of lentiviral vector in gene overexpressing cell model .Methods Wild type DJ-1 and L166P mutant DJ-1 lentiviral vector plasmids were respectively constructed .After sequencing and comparing cor-rectly, the plasmid was amplified and transfected into HEK 293T cell line.Expression of WT DJ-1 and L166P mu-tant DJ-1 in cell lines was detected by fluorescence and Western blot .After determining the accurate expression of the target protein, a large amount of HEK293T cells was transfected and packaged to produce lentiviral particles. The PC12 cells were infected with the titer of virus supernatant.The fluorescence intensity of GFP and the expres-sion of target protein were observed by fluorescence microscope and Western blot method ,and the infection effi-ciency of the virus was determined .Results Lentiviral vectors carrying wild type DJ-1 and its mutants were suc-cessfully constructed .The virus vector can be transfected into HEK 293T cells and the target protein can be correctly expressed.The viral titers of LV-DJ-1 and LV-DJ-1/L166P were 2×109 TU/mL and 2×108 TU/mL, respectively. Virus supernatant can efficiently infect PC 12 cells, and most cells can express target proteins .The protein expres-sions of exogenous wild-type DJ-1 and L166P mutants were 315% and 285% of endogenous content ,respectively. Conclusions Lentivirus vector can infect cells efficiently , and it is a good way to prepare gene over expressing cell model.A cell model overexpressing DJ-1 or its L166P mutant is successfully prepared .The model can be used for subsequent DJ-1 function research .