Establishment of oxygen glucose deprivation reperfusion model of senescent SH-SY5Y cells

Obejective:To explore the establishment of an oxygen glucose deprivation/reperfusion model of senescent SH-SY5Y cells.Methods:SH-SY5Y cells were randomly divided into control(D-galactose 0 mmol/L group),D-galactose(25 mmol/L,50 mmol/L,100 mmol/L,200 mmol/L,400 mmol/L)groups,and treated with corresponding concentrations of D-galactose for 48 h.The changes of cell morphology,β-galactosidase,the cell morphology,β-galactosidase activity by microscopic observation,cell proliferation rate by EdU kit and cell survival rate by CCK-8 assay were used to determine the decaying concentration of D-galactose and to establish the senescence model.The senescent SH-SY5Y cells were randomly divided into control group(oxygen glucose deprivation without treatment group),oxygen glucose deprivation treatment(0.5 h,1 h,1.5 h,2 h)group,followed by re-glucose reoxygenation for 24 h,and CCK-8 assay for the survival rate of senescent SH-SY5Y cells.Results:There were no significant changes in cell morphology and β-gal activity in the 25 mmol/L and 50 mmol/L groups compared with the control group(P>0.05),cytosolic hypertrophy was seen in the cells of the 100 mmol/L group,chromatin fixation in the cells of the 200 mmol/L group,and massive vacuolization in the cells of the 400 mmol/L group;the positive rate ofβ-galactosidase staining in the cells of the(100-400 mmol/L)group was significantly higher compared with the control group(P<0.05),with little difference between the 100 mmol/L and 200 mmol/L groups(P>0.05);the cell proliferation ability of the(100-400 mmol/L)group was significantly decreased in a concentration-dependent manner(P<0.05);the cell survival rate was decreased in a concentration-dependent manner(P<0.05),with IC_(50) between 100 mmol/L and 200 mmol/L.The survival of senescent SH-SY5Y cells showed a time-dependent decrease in oxygen-glucose deprivation(P<0.05),with an IC_(50) close to 1 h.Conclusion:D-gal concentration of 100 mmoL/L and 48 h of cell action could establish a survival rate of about 50%of senescent SH-SY5Y cells,and oxygen glucose deprivation of senescent SH-SY5Y cells for 1 h and reperfusion for 24 h could establish an oxygen glucose deprivation/reperfusion model of senescent SH-SY5Y cells with a survival rate close to 50%.

Overexpression of the neuroglobin gene delivered by ultrasound-targeted microbubble destruction protects SH-SY5Y cells against cobalt chloride induced hypoxia

In this study, we examined the effects of neuroglobin gene （Ngb） transfection into SH-SY5Y cells, using ultrasound-targeted microbubble destruction （UTMD）, on cobalt chloride-induced hypoxia. With an ultrasound intensity of 0.8 W/cm2, a 60-second exposure duration, 50% duty cycle, and 20% microbubble concentration, pAcGFP1-C1-Ngb-transfected cells exhibited the highest cell viability and transfection efficiency. The efficiency of plasmid delivery was significantly higher with UTMD than transfection with plasmid alone, transfection with plasmid using microbubbles, or transfection of plasmid by ultrasound. In addition, during cobalt chloride-induced hypoxia, caspase-3 activity in pAcGFP1-C1-Ngb-transfected cells was significantly lower than in untransfected cells. Ngb protein and mRNA expression were significantly higher in cells transfected by UTMD than in cells transfected with the other methods. These results demonstrate that UTMD can very efficiently mediate exogenous gene delivery, and that Ngb overexpression protects cells against cobalt chloride-induced hypoxia.

Geniposide protects human neuroblastoma SH-SY5Y cells against corticosterone-induced injury

In vitro cultured human neuroblastoma SH-SY5Y cells were pretreated with 50 or 5 ug/mL geniposide for 12 hours and exposed to 400 umol/L corticosterone. Corticosterone exposure in cultures not pretreated with geniposide resulted in inhibited cell growth, reduced cell survival, and increased P53 and P21 protein expression. However, in geniposide pretreated SH-SY5Y cells, cell viability and the number of cells in the G2 phase of the cell cycle were significantly increased, P21 and P53 protein expression was reduced, and cell apoptosis was inhibited following corticosterone exposure. These results indicate that geniposide can protect SH-SY5Y cells against high-dose corticosterone-induced injury.

Shuyusan-containing serum protects SH-SY5Y cells against corticosterone-induced impairment

The Chinese herb Shuyusan, whose main constituent is jasminoidin, has been shown to protect SH-SY5Y cells against corticosterone-induced damage. SH-SY5Y cells injured by 400 μmol/L cor- ticosterone were treated with 5 and 30 μg/mL Shuyusan-containing serum. Results revealed that Shuyusan-containing serum elevated the survival rate of SH-SY5Y cells, reduced Bax expression, increased Bcl-2 expression, markedly elevated brain-derived neurotrophic factor mRNA expression, and blocked cell apoptosis. Moreover, the effect of high-dose （30 μg/mL） Shuyusan-containing se- rum was more remarkable. Therefore, Shuyusan-containing serum appears to protect SH-SY5Y cells against corticosterone-induced impairment by adjusting the expression of apoptosis-associ- ated proteins and brain-derived neurotrophic factor. Moreover, high-dose Shuyusan-containing se- rum has a protective effect on high-dose corticosterone-induced impairment.

Chronic neuroprotective effects of low concentration lithium on SH-SY5Y cells:possible involvement of stress proteins and gene expression

To investigate the molecular mechanism underlying the neuroprotective effect of lithium on cells, in this study, we exposed SH-SY5Y cells to 0.5 mmol/L lithium carbonate （Li2CO2） for 25-50 weeks and then detected the expression levels of some neurobiology related genes and post-translational modifications of stress proteins in SH-SYSY cells, cDNA arrays showed that pyruvate kinase 2 （PKM2） and calmodulin 3 （CaM 3） expression levels were significantly down-regulated, phosphatase protein PP2A expression was lightly down-regulated, and casein kinase II （CK2）, threonine/tyrosine phosphatase 7 （PYST2）, and dopamine beta-hydroxylase （DBH） expression levels were significantly up-regulated. Besides, western blot analysis of stress proteins （HSP27, HSP70, GRP78 and GRP94） showed an over-expression of two proteins： a 105 kDa protein which is a hyper-phosphorylated isoform of GRP94, and a 108 kDa protein which is a phosphorylated tetramer of HSP27. These results suggest that the neuroprotective effects of lithium are likely related to gene expressions and post-translational modifications of proteins cited above.

Levetiracetam induces tyrosine kinase receptor B expression in SH-SY5Y cells

Tyrosine kinase receptor B （TrkB） plays an important role in long-term potentiation and memory formation.The present study used all-trans retinoic acid to induce TrkB expression in SH-SY5Y cells,and observed the effects of levetiracetam （LEV） on TrkB expression.Following exposure to 10,50,and 100 μg/mL LEV,the number of TrkB-positive cells,and average absorbance value were increased.Results demonstrated that LEV can induce TrkB expression in SH-SY5Y cells.

Two potentially specific but relevant patterns of proteomic change Response of SH-SY5Y cells to differentiation with retinoic acid followed by phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate, and susceptibility of differentiated cells to dopamine

Dopamine （DA） exposure at a dose of 100 pmol/L for 24 hours causes oxidative stress in SH-SY5Y cells with induction of neuronal differentiation by retinoic acid （RA,10 pmol/L,72 hours） followed by phorbol ester 12-O-tetradecanoyl-phorbol-13-acetate （TPA,80 nmol/L,72 hours）. However,it remains unclear whether the alteration of phenotype observed in response to oxidative stress is associated with protein regulation in this cellular model for Parkinson＇s disease. The present study detected protein regulation affected by oxidative stress at a proteomic level：selection of differentially altered proteins using two dimensional difference in-gel electrophoresis and identification of these proteins using matrix assisted laser desorption/ionization time-of-flight mass spectrometry. The results demonstrated significant alterations in expression of six proteins in SH-SY5Y cells following the differentiation and fourteen proteins in the differentiated cells following the exposure,exemplified by an increase of tubulin alpha1 in the former but a decrease of tubulin alpha-ubiquitous chain in the latter. These results suggest that two potentially specific but relevant patterns of proteomic change may be produced in SH-SY5Y cells with the induction of differentiation by RA followed by TPA,and in the differentiated cells after DA exposure.

Identification of differentially expressed proteins in SH-SY5Y cells treated with resveratrol

To gain insight into the molecular mechanisms of resveratrol-mediated neuroprotection, two-dimensional difference gel electrophoresis in combination with matrix-assisted laser desorption ionization time-of-flight mass spectrometry was used to identify proteins differentially-expressed in SH-SY5Y cells treated with resveratrol. Compared with the control group, resveratrol treatment significantly affected the expression of four proteins： endoplasmic reticulum oxidoreductin 1-like protein alpha, p21-activated kinase 1, Archain 1, and T cell receptor beta chain. The former three were downregulated and the latter was upregulated. These proteins are primarily associated with endoplasmic reticulum stress, intracellular trafficking, and immune function.

The recovery and protective effects of asiatic acid on differentiated human neuroblastoma SH-SY5Y cells cytotoxic-induced by cholesterol

Objective:To investigate the effect of asiatic acid(AA) on the differentiated human neuroblastoma SH-SY5 Y cells cytotoxic-induced by cholesterol.Methods:Human neuroblastoma SH-SY5 Y cells were either exposed to different concentrations of AA or treated with different doses of cholesterol to reveal their responding viability by MTT assay.The selective 1 mmol/L concentration of AA was then used to test for either the protective or the recovery effects on the cells treated with 250 mmol/L concentration of cholesterol.Results:AA has a propensity to directly increase the viability of differentiated human neuroblastoma SH-SY5 Y cells.Cholesterol has significant cytotoxic effect on those cells in a concentration-dependent manner.AA has the ability to slightly recover the viability of the differentiated culture cytotoxic-induced by cholesterol but could not protect those cells from cytotoxic-induced by cholesterol.Conclusions:High concentrations of cholesterol were observed to be harmful to the neurons and AA had a slight effect of reducing neuronal death caused by cholesterol.

Valproic acid alters differential protein expression in SH-SY5Y cells

This study sought to identify differentially expressed proteins in SH-SY5Y cells treated with valproic acid, using two-dimensional difference gel electrophoresis analysis. Three proteins were unambi-guously identified： the eukaryotic translation initiation factor 4A isoform 1 and ATP6V1B2 protein were downregulated, while the heterogeneous nuclear ribonucleoprotein K was upregulated. Moreover, all three proteins are associated with altered expression due to oxidative stress. Ma-trix-assisted laser desorption/ionization-time of flight mass spectrometry and protein immunoblotting assay confirmed the differential expression of eukaryotic translation initiation factor 4A isoform 1. The results indicate that valproic acid exerts an antioxidation effect by regulating the expression of eukaryotic translation initiation factor 4A isoform 1.

Effects of brain-derived neurotrophic factor on induced differentiation of SH-SY5Y cells in vitro

BACKGROUND： Previous studies have demonstrated that brain-derived neurotrophic factor （BDNF） promotes neural differentiation. However, the mechanisms involved in cell cycle-related protein regulation, which highly correlates to neural proliferation and apoptosis, remain poorly understood. OBJECTIVE： To investigate the effects of various concentrations of BDNF on cycle-related protein mRNA expression in induce-differentiated SH-SY5Y cells in vitro prior to and following G2 phase, and to analyze the neuroprotective effects of BDNF. DESIGN, TIME AND SETTING： A comparison, observational study, based on cell biology, was performed at the Department of Biochemistry, Medical College of Tongji University, from March 2005 to October 2006. MATERIALS： SH-SY5Y cells were provided by Shanghai Institute of Cytology, Chinese Academy of Science; BDNF by Alomone Labs, Israel; all-trans retinoic acid （ATRA） by Sigma-Aldrich, USA. METHODS： SH-SY5Y cells were randomly divided into three groups： blank control [cells were treated in Insulin-Transferrin-Selenium （ITS） solution for 7 days], ATRA （cells were treated with ITS solution containing 10 μmol/L ATRA for 7 days）, and BDNF （cells were treated identical to the ATRA group for 5 days, and then respectively treated in ITS solution containing 1, 10, and 100 μg/L BDNF for 2 days）. The experiment was repeated three times for each group. MAIN OUTCOME MEASURES： mRNA expression levels of cyclin A1, B1, B2, cyclin-dependent kinase 1, and 5 were detected using quantitative real-time RT-PCR; percentage of cells in G1, S, and G2 phases were detected using fluorescence-activated cell sorting. RESULTS： mRNA expression levels of cyclin A1 in the high-dose BDNF group was significantly less than the ATRA group （P 〈 0.05）.mRNA expression levels of cyclin B1 was significantly less in the different BDNF concentration groups compared with the control and ATRA groups （P 〈 0.05 or P 〈 0.01）. mRNA expression levels of cyclin B2 and cyclin-dependent kinase 1 were significantly decreased in the high-dose BDNF group （P 〈 0.05 or P 〈 0.01）. Cyclin-dependent kinase 5 mRNA expression was significantly greater in the low-dose and moderate-dose BDNF groups compared with the ATRA group （P 〈 0.05）. The percentage of cells in G1 phase was significantly greater in the different BDNF concentration groups compared with the ATRA and control groups （P 〈 0.01）. Moreover, the percentage of cells in S phase was significantly less in the three BDNF groups compared with the ATRA group （P 〈 0.01）. However, the percentage of cells in S phase was significantly less in the low-dose and high-dose BDNF groups compared with the control group （P 〈 0.01）. CONCLUSION： BDNF enhanced the percentage of cells in G1 phase, but did not alter mRNA expression of cell cycle-related proteins prior to or following G2 phase. These results suggested that BDNF was not a risk factor for inducing apoptosis.

Protective effect of Fructus Mume total flavone against SH-SY5Y cells damage induced by MPP+and its mechanism

Objective:To investigate the neuroprotective effects of Fructus Mume total flavone(FMF)against cell apoptosis and mitochondrial injury induced by 1-methyl-4-phenylpyridinium(MPP^(+))in human neuroblastoma(SH-SY5Y)cells and explore its molecular mechanisms.Methods:MPP^(+) induced SH-SY5Y cells injury model were established in vitro cell culture,the cells were divided into 5 groups:normal control group,model group(250μmol·L^(-1) MPP^(+)),FMF low-and middle-and high-dose experimental group(10,50,100μmol·L^(-1) FMF).After 72 h administration,4’,6-diamidino-2-phenylindole(DAPI)staining was used to observe the effects of different concentrations of FMF on the morphologic changes of apoptotic cells,the ratio of cell apoptosis was measured by Annexin-FITC/PI double staining.The mitochondrial membrane electro-bit were detected by flow cytometry(FCM).The expression of Bcl-2,Bax and Caspase-3 were detected by Western blot.Results:The results of DAPI staining showed that the injury SH-SY5Y cells induced by MPP+were densely condensed,the nucleus showed nuclear shrinkage,showing an apoptotic characteristic morphology;after 72h of FMF action,the apoptotic morphology of the cells showed different degrees of improvement,and the apoptotic number of SH-SY5Y cells also decreased.Compared with that in the normal control group,the apoptotic rate and of mitochondrial membrane electrobit of SH-SY5Y cells in the model group increased significantly(P<0.01),the expression of Bax and Caspase-3 proteins increased significantly(P<0.01),Bcl-2 protein and the ratio of Bcl-2/Bax decreased significantly(P<0.01).Compared with that in the model group,the apoptotic rate and mitochondrial membrane electro-bit of SH-SY5Y cells in FMF groups(10,50,100μmol·L^(-1))were significantly lower,while Bax and Caspase-3 proteins were significantly lower(P<0.01),and Bcl-2 protein and the ratio of Bcl-2/Bax were significantly higher,with statistically significant difference in FMF middle-and high-dose experimental groups(P<0.01).The results indicated that FMF can decrease the experession level of Bax and Caspase-3 and increase the ratio of Bcl-2/Bax,inhibit MPP+induced apoptosis.Conclusion:FMF improves the damage of SH-SY5Y cells induced by MPP+,and plays a neuroprotective effect by regulating the expressions of related proteins in mitochondrial apoptosis pathway.

Effect of Alteration of Glutathione Content on Cell Viability in α-Synuclein-Transfected SH-SY5Y Cells

It is well known that α-synuclein (αS) plays an important role in the pathogenesis of Parkinson’s disease (PD). Moreover, oxidative stress is also thought to be an important factor in PD due to induction of dopaminergic neuronal cell death by free radicals and enhancement of αS fibrillation by oxidized stress. In the present study, to clarify the role of glutathione (GSH), an intracellular antioxidant, on the molecular mechanism of αS-induced cell injury, we examined the effects of L-buthionine-SR-sulfoximine (BSO), a GSH synthase inhibitor, with or without N-acetyl-L-cysteine (NAC), a source of GSH, on αS-induced cell injury in human neuroblastoma SH-SY5Y cells. Treatment with BSO significantly reduced the cell viability of both empty-vector- and αS-transfected SH-SY5Y cells in a dose-dependent manner (p < 0.01), although the ratio of αS-induced reduction of cell viability in α-syn-transfected cells was much greater than that in empty-vector-transfected cells. Moreover, BSO significantly reduced the intracellular total GSH level in both types of transformant cells. However, NAC significantly prevented BSO-induced reduction of both cell viability and GSH level in the αS-transfected cells. These findings suggest that GSH plays an important role in αS-induced cell injury by reducing cell viability.

Aged Garlic Extract Reduces ROS Production and Cell Death Induced by 6-Hydroxydopamine through Activation of the Nrf2-ARE Pathway in SH-SY5Y Cells

Many degenerative or pathological processes, such as aging, cancer and coronary heart disease, are related to reactive oxygen species (ROS) and radical-mediated reactions. We examined the effectiveness of aged garlic extract (AGE), a garlic preparation rich in water-soluble cysteinyl moieties, for protection of cells from ROS produced by 6-hydroxy-dopamine (6-OHDA) using human neuroblastoma SH-SY5Y cells. Concomitant treatment of cells with AGE (2 and 4 mg/ml) showed the dose-dependent protective effect on the cell death induced by 6-OHDA. In addition, the AGE treatment significantly suppressed the increase of ROS generation by 6-OHDA. Furthermore, the protective effect of AGE was accompanied by activation of the nuclear factor erythroid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) pathway and the increase of mRNAs of heme oxygenase-1 and NAD(P)H quinone oxidoreductase 1. These two enzymes are important in the cellular antioxidant system. These results indicated that AGE protected cells from ROS damage by not only capturing ROS directly but also activating the cellular antioxidant system by stimulating antioxidant gene expression via the Nrf2-ARE pathway. The present study suggested that AGE may be useful for prevention and treatment of cell damage caused by ROS.

ERβ modulation and non-modulation of ERα by administration of geniposide and panax notoginseng saponins in SH-SY5Y cells

Objective:To illustrate the effect of geniposide (GP) and panax notoginseng saponins (PNS) on estrogen receptors (ER) including ERα and ERβ within the cytoplasm and nucleus of SH-SY5Y cells.Methods:Immunofluorescence was used to observe the distribution of ERα and ERβ in cytoplasm and nucleus,but Western blot was only for ERβ detection.q-PCR was applied to detect NR3C1,S100A6 and LGALS1downstream mRNA gene expression levels of ER.Results:Through analyzing fluorescence intensity under the administration of GP and PNS in SHSY5Y cells,we found that the distribution of ERα has not been affected.We also discovered that GP and/or PNS significantly stimulated the transportation of ERβ into the nucleus in a timedependent manner (all P <.001).When SH-SY5Y cells were treated with supplements of GP,PNS,GP + PNS at 15 minutes,30 minutes and 45 minutes,the distribution of ERβ in the nucleus significantly increased compared with that in control group (all P <.001).Evidently,treatment with GP,PNS,GP + PNS was able to significantly increase the levels of ERβ protein within the nucleus compared with control group at both 30 minutes and 45 minutes intervals (all P <.001).Furthermore,GP and PNS showed signs of activating to NR3C1 and LGALS1,two genes downstream of ER.It is possible that the 5100A6 gene mainly encoded the downstream gene in ERα's signaling pathway,which was not affected after the treatment of GP and/or PNS.Conclusion:The distribution and expression of ERβ has been modulated under the administration of GP + PNS within the SH-SY5Y cells,whereas ERα has not.GP and PNS in combination may play an estrogenic-like effect with selectivity on ERβ modulation.

Beyond boundaries:Neuroprotective effects of steroids and ecdysteroids in SH-SY5Y cells-A systematic review

Steroids and ecdysteroids have been shown to exhibit a range of biological effects,including anti-inflammatory,anticancer,and neuroprotective.This systematic review aims to highlight the evidence-based neuroprotective and antioxidant effects of steroids and ecdysteroids in SH-SY5Y neuroblastoma cells.A comprehensive literature search was conducted on May 11,2023,without publication source restrictions,using various electronic databases,including PubMed,Web of Science(WoS),Scopus,and Cumulative Index toNursing and Allied Health Literature.Of 103articles,only20 studies were included for investigating the neuroprotective effects of steroids and ecdysteroids in SH-SY5Y cells exposed to oxidative stress or neurotoxic agents.The risk of bias and quality assessment of the included studies were evaluated in accordance with the Nature Publication Quality Improvement Project specific criteria.The selected studies reported the antioxidant effects of the tested compounds on SH-SY5Y cells and demonstrated their ability to scavenge free radicals and prevent lipid peroxidation.These findings suggest that neurosteroids have potential therapeutic applications for the prevention and treatment of neurodegenerative diseases characterized by oxidative stress and neuronal damage.Some studies have investigated the molecular mechanisms underlying the neuroprotective and antioxidant effects of steroids and ecdysteroids in SH-SY5Y cells.These mechanisms include the activation of antioxidant enzymes,such as superoxide dismutase and glutathione peroxidase,and the modulation of various signaling pathways,including the phosphoinositide 3-kinase/protein kinase B and mitogen-activated protein kinase/extracellular signal-regulated kinase pathways.This review provides evidence that the tested compounds have remarkable neuroprotective and antioxidant effects in human neuroblastoma SH-SY5Y cells.

Cellular Lipidome Changes during Retinoic Acid(RA)-Induced Differentiation in SH-SY5Y Cells:A Comprehensive In Vitro Model for Assessing Neurotoxicity of Contaminants

The SH-SY5Y,neuroblastoma cell line,is a common in vitro model used to study physiological neuronal function and the neuronal response to different stimuli,including exposure to toxic chemicals.These cells can be differentiated to neuron-like cells by administration of various reagents,including retinoic acid or phorbol12-myristate-13-acetate.Despite their common use,there is an incomplete understanding of the molecular changes that occur during differentiation.Therefore,there is a critical need to fully understand the molecular changes that occur during differentiation to properly study neurotoxicity in response to various environmental exposures.Previous studies have investigated the proteome and transcriptome during differentiation;however,the regulation of the cellular lipidome in this process is unexplored.In this work,we conducted liquid chromatography−mass spectrometry(LC−MS)-based untargeted lipidomics in undifferentiated and differentiated SH-SY5Y cells,induced by retinoic acid.We show that there are global differences between the cellular lipidomes of undifferentiated and differentiated cells.Out of thousands of features detected in positive and negative electrospray ionization modes,44 species were identified that showed significant differences(p-value≤0.05,fold change≥2)in differentiated cells.Identification of these features combined with targeted lipidomics highlighted the accumulation of phospholipids,sterols,and sphingolipids during differentiation while triacylglycerols were depleted.These results provide important insights into lipid-related changes that occur during cellular differentiation of SH-5YSY cells and emphasize the need for the detailed characterization of biochemical differences that occur during differentiation while using this in vitro model for assessing ecological impacts of environmental pollutants.

miR-181a靶向Bcl-2调控氧糖剥夺/再灌注模型诱导的SH-SY5Y神经细胞凋亡

目的皮层是响应脑缺血缺氧最为敏感的组织之一,基于前期深度测序技术,我们筛选获得响应脑缺血缺氧应激的皮层区目标基因miR-181a及Bcl-2。本研究旨在SH-SY5Y细胞株氧糖剥夺/复糖复氧模型验证二者靶向调控关系及功能,明确miR-181a—Bcl-2调控网络在OGD/R诱导的神经细胞凋亡中的作用。方法采用线栓法构建大鼠缺血缺氧再灌注损伤模型,脑切片TTC染色及行为学评分法评估模型。应用qRT-PCR及Western Blot验证目标基因的表达。生物信息学分析miR-181a与Bcl-2的靶向结合位点并比对结合位点的保守性,双荧光素酶报告基因实验验证miR-181a与Bcl-2靶向结合的特异性。采用OGD/R细胞模型体外模拟脑缺血再灌注损伤,检测凋亡相关蛋白表达及Hoechst荧光染色评估细胞凋亡。结果大鼠大脑中动脉阻塞后miR-181a、Bcl-2表达变化趋势相反。RNA hybird软件预测miR-181a可结合Bcl-2的3′-UTR区,且结合区域高度保守。双荧光素酶报告基因实验发现,相对于Bcl-23′UTR-WT与mimic-NC共转染组,Bcl-23′UTR-WT与miR-181a mimic共转染后的荧光活性更低(P<0.001),而Bcl-2-Mut与miR-181a mimic共转染组,荧光活性无显著差异(P>0.05)。分别用miR-181a的模拟物及抑制物转染OGD/R诱导的SH-SY5Y细胞,miR-181a可以抑制Bcl-2 mRNA及其蛋白的表达水平(P<0.001)。过表达miR-181a显著增加了SH-SY5Y细胞的凋亡(P<0.001),而抑制miR-181a表达可使SH-SY5Y细胞凋亡显著降低(P<0.001)。结论miR-181a可靶向结合Bcl-2,下调miR-181a可通过促进Bcl-2的表达进而抑制SH-SY5Y神经细胞OGD/R损伤诱导的细胞凋亡。

槟榔碱对H_(2)O_(2)诱导SH-SY5Y神经细胞氧化应激损伤的保护作用及机制研究

本研究通过建立过氧化氢(H_(2)O_(2))诱导的SH-SY5Y神经细胞氧化应激模型,旨在探究槟榔碱对氧化应激诱导神经细胞损伤的保护作用及其作用机制。采用CCK-8法检测细胞活力,采用分光光度法检测乳酸脱氢酶(LDH)释放、丙二醛(MDA)含量、超氧化物歧化酶(SOD)和过氧化氢酶(CAT)活性,采用流式细胞术检测细胞凋亡、线粒体膜电位,采用Western blot技术检测Nrf2、HO-1、Keap1、Bcl-2、Bax、Caspase-3的表达。结果表明:槟榔碱干预均能有效降低细胞凋亡并显著上调线粒体膜电位;在提高SOD、CAT水平的同时降低MDA水平;140μmol/L槟榔碱处理能够显著上调Nrf2、HO-1、Bcl-2蛋白的表达(P<0.001,P<0.0001),并下调Keap1、Bax、Caspase-3蛋白的表达(P<0.001,P<0.0001)。表明槟榔碱能够有效改善H_(2)O_(2)诱导的氧化应激损伤,其作用机制与激活Nrf2/HO-1信号通路、提升细胞抗氧化活力、调控Bcl-2/Bax/Caspase-3信号通路和抑制细胞凋亡有关。

佛手多糖对1-甲基-4-苯基-吡啶离子诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用研究

该文探究佛手多糖对1-甲基-4-苯基-吡啶离子(1-methyl-4-phenyl-pyridine ion,MPP+)诱导人神经母细胞瘤(SH-SY5Y)细胞损伤的保护作用及其机制。佛手多糖经大孔吸附树脂AB-8进行纯化。体外培养SH-SY5Y细胞,构建帕金森病(Parkinson′s disease,PD)细胞模型,实验分为对照组、MPP+模型组、佛手多糖组。采用噻唑蓝(methye thiazdye telrazlium,MTT)法检测细胞存活率,Hoechst33258染色法观察细胞形态,2′,7′-二氯荧光黄双乙酸盐荧光探针检测细胞活性氧(reactive oxygen species,ROS)水平,JC-1荧光探针法检测线粒体膜电位,蛋白免疫印迹(Western blot)检测磷酸化蛋白激酶B(phosphorylated protein kinase B,p-Akt)、蛋白激酶B(protein kinase B,Akt)、磷酸化细胞外调节蛋白激酶(phosphorylated extracellular regulated protein kinases1/2,p-ERK1/2)和细胞色素c(cytochrome c,Cyt-c)蛋白表达水平。结果表明,佛手多糖的得率4.86%,纯度为44.46%,经过AB-8纯化后,纯度提高到60.81%;与对照组相比,模型组细胞的存活率显著降低,Hoechst33258染色下可见细胞破碎,细胞核皱缩,细胞内ROS显著增加,线粒体膜电位显著降低。与模型组相比,佛手多糖组的细胞存活率显著增加,细胞形态明显得到改善,ROS水平下降,线粒体膜电位升高。Western blot结果显示,佛手多糖能抑制MPP+引起的p-Akt和p-ERK1/2的降低,以及Cyt-c的上升。综上,佛手多糖对MPP+诱导SH-SY5Y细胞损伤具有保护作用,其机制可能是通过调节线粒体ROS的产生和Cyt-c的释放,进而维持线粒体稳态,激活Akt信号通路和ERK信号通路,抑制细胞的凋亡,从而起到保护作用。研究结果可为缓解帕金森病的发生发展提供理论依据,同时也能更好地开发和利用佛手资源。