Apoptosis In SH-SY5Y Cells Research Articles

Cordycepin exacerbates cadmium-induced neurotoxicity via promoting endoplasmic reticulum stress-associated apoptosis

• Exposure of Cor deteriorated Cd-induced learning and memory deficits in mice. • Cor promoted Cd-induced neuronal apoptosis both in vivo and vitro. • The ER stress pathway was involved in the increased Cd- and Cor-induced neurotoxicity. Cordycepin (Cor) is a potent bioactive constituent of Cordyceps militaris , which has been used as a daily tonic food and herbal medicine in Asia. Cadmium (Cd) is a widespread neurotoxic environmental contaminant, and it has been detected as a pollutant in Cordyceps militaris . However, the potential effects of Cor on Cd neurotoxicity remains unknown. This study aimed to investigate the effects and possible mechanisms of Cor on neurotoxicity in Cd-induced cell and preclinical models. It was observed that Cor administration aggravated Cd-induced cognitive impairment and neurotoxicity in mice, exerted synergistic growth inhibition, and promoted apoptosis of SH-SY5Y cells. These effects were found to be mediated through the activation of endoplasmic reticulum (ER) stress. Overall, our findings suggest that Cor can increase Cd-induced neurotoxicity via promoting ER stress-associated apoptosis. These observations may support the implementation of stricter criterion for the detection of Cd in Cordyceps militaris , to keep the consumers safe.

MicroRNA-181a\u20132\u20133p shuttled by mesenchymal stem cell-secreted extracellular vesicles inhibits oxidative stress in Parkinson\u2019s disease by inhibiting EGR1 and NOX4

The current study investigated the physiological mechanisms by which extracellular vesicle (EV)-encapsulated miR-181a–2–3p derived from mesenchymal stem cells (MSCs) might mediate oxidative stress (OS) in Parkinson’s disease (PD). First, 6-hydroxydopamine (6-OHDA)-induced PD cell and mouse models were established, after which miR-181a–2–3p, EGR1, and NOX4 expression patterns were determined in SH-SY5Y cells and substantia nigra (SN) of PD mice. Next, the binding affinity among miR-181a–2–3p, EGR1, and NOX4 was identified using multiple assays. Gain- or loss-of-function experiments were further adopted to detect SH-SY5Y cell proliferation and apoptosis and to measure the levels of SOD, MDA, and ROS. Finally, the effects of miR-181a–2–3p from MSC-derived EVs in PD mouse models were also explored. It was found that miR-181a–2–3p was poorly expressed in 6-OHDA-induced SH-SY5Y cells, whereas miR-181a–2–3p from MSCs could be transferred into SH-SY5Y cells via EVs. In addition, miR-181a–2–3p could target and inhibit EGR1, which promoted the expression of NOX4. The aforementioned miR-181a–2–3p shuttled by MSC-derived EVs facilitated SH-SY5Y proliferation and SOD levels, but suppressed apoptosis and MDA and ROS levels by regulating EGR1 via inhibition of NOX4/p38 MAPK, so as to repress OS of PD. Furthermore, in PD mice, miR-181a–2–3p was carried by EVs from MSCs to alleviate apoptosis of dopamine neurons and OS, accompanied by increased expressions of α-syn and decreased 4-HNE in SN tissues. Collectively, our findings revealed that MSC-derived EV-loaded miR-181a–2–3p downregulated EGR1 to inhibit OS via the NOX4/p38 MAPK axis in PD.

Selenite Ameliorates Cadmium-induced Cytotoxicity Through Downregulation of ROS Levels and Upregulation of Selenoprotein Thioredoxin Reductase 1 in SH-SY5Y Cells.

Cadmium (Cd) as a ubiquitous toxic heavy metal in the environment, causes severe hazards to human health, such as cellular stress and organ injury. Selenium (Se) was reported to reduce Cd toxicity and the mechanisms have been intensively studied so far. However, it is not yet crystal clear whether the protective effect of Se against Cd-induced cytotoxicity is related to selenoproteins in nerve cells or not. In this study, we found that Cd inhibited selenoprotein thioredoxin reductase 1 (TrxR1; TXNRD1) and decreased the expression level of TrxR1, resulting in cellular oxidative stress, and Se supplements ameliorated Cd-induced cytotoxicity in SH-SY5Y cells. Mechanistically, the detoxification of Se against Cd is attributed to the increase of the cellular TrxR activity and upregulated TrxR1 protein level, culminating in strengthened antioxidant capacity. Results showed that Se supplements attenuated the ROS production and apoptosis in SH-SY5Y cells, and significantly mitigated Cd-induced SH-SY5Y cell death. This study may be a valuable reference for shedding light on the mechanism of Cd-induced cytotoxicity and the role of TrxR1 in Se-mitigated cytotoxicity of Cd in neuroblast cells, which may be helpful for understanding the therapeutic potential of Cd and Se in treating or preventing neurodegenerative diseases, like Alzheimer's disease (AD) and Parkinson's disease (PD).

Curcumin Attenuates the PERK-eIF2α Signaling to Relieve Acrylamide-Induced Neurotoxicity in SH‑SY5Y Neuroblastoma Cells.

Curcumin is a natural polyphenolic compound with neuroprotective and antioxidant properties. Acrylamide (ACR) is a by-product of food processing that produces neurotoxicity in humans and animals. The pancreatic endoplasmic reticulum kinase (PERK)-eukaryotic initiation factor-2α (eIF2α) signaling is involved in the occurrence of neurotoxicities. This study is aimed to investigate the protective effect of curcumin on ACR-induced cytotoxicity and explore the role of PERK-eIF2α signaling in this process. ACR exposure at 2.5 mM for 24h caused oxidative stress as revealed by the distinct increase in cellular reactive oxygen species (ROS) and malondialdehyde (MDA) level, and a significant decrease in glutathione (GSH) content. ACR induced phosphorylated tau aggregation, phosphorylated cAMP response elements binding protein (CREB) reduction, and Bax/Bcl-2 ratio up-regulation in SH-SY5Y cells. ACR also activated the PERK-eIF2α signaling in SH-SY5Y cells and triggered the activation of glycogen synthase kinase-3β (GSK-3β), up-regulated activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP). Curcumin pretreatment significantly attenuated ACR-induced neuronal toxicity as revealed by the ameliorated cell viability, mitigated intracellular ROS and MDA level, and elevated GSH content. Moreover, curcumin pretreatment inhibited PERK-dependent eIF2α phosphorylation, further suppressed GSK-3β and ATF4 function, and abolished abnormal tau phosphorylation, P-CREB reduction, and CHOP-induced apoptosis in SH-SY5Y cells. These results provided empirical evidence between curcumin and PERK-eIF2α signaling in ACR-induced neurotoxicity.

The neuroprotective effects of Galectin-1 on Parkinson's Disease via regulation of Nrf2 expression.

Parkinson's disease (PD) is one of the neurodegenerative diseases. Galectin-1 (Gal-1) is expressed in the central nervous system. Our study sought to explore the neuroprotective effect of Gal-1 in 1‑methyl‑4‑phenyl pyridine ion (MPP+)-induced cytotoxicity on SH-SY5Y cells. SH-SY5Y cells were cultured in vitro, pretreated with Gal-1, and then exposed to MPP+. Thereafter, the generation of reactive oxygen species (ROS) in SH-SY5Y cells was investigated. The effects of Gal-1 on DNA breakage, cell damage (release of lactate dehydrogenase (LDH)), viability, and apoptosis in SH-SY5Y cells were examined by comet assay, LDH assay, WST-1 assay, and flow cytometry, respectively. Additionally, the regulatory effect of Gal-1 on Nrf2 expression was examined by western blot. Zebrafish embryos were pretreated with Gal-1 and then exposed to MPP+. The locomotor ability of zebrafish larvae was then investigated. MPP+ induced the production of ROS in cells, which can be alleviated by pretreatment with Gal-1. Gal-1 protected cells from MPP+-induced cytotoxicity by preventing DNA breakage and cell injury. Gal-1 inhibited apoptosis in SH-SY5Y cells. The neuroprotective effect of Gal-1 could be abolished when Nrf2 expression knockdown. Moreover, exposure to MPP+ decreased the locomotor activity of zebrafish, which was attenuated by pretreatment with Gal-1. Our study demonstrated that the administration of Gal-1 could protect neurons from cellular stress by preventing apoptosis and eliminating ROS. Moreover, the neuroprotective effect of Gal-1 in neuronal cells could be related to the activation of Nrf2 expression. Therefore, Gal-1 could be a promising strategy for treating PD.

LncRNA SNHG12 ameliorates bupivacaine-induced neurotoxicity by sponging miR-497-5p to upregulate NLRX1.

Long non-coding RNA (lncRNA) small nucleolar RNA host gene 12 (SNHG12) has been reported to participate in the regulation of various nervous system disorders. Bupivacaine (BV), a commonly used local anesthetic, could generate neurotoxicity in neurons. This work intended to investigate the role and specific mechanism of SNHG12 in BV-induced neurotoxicity. In this study, we established an in vitro cell model of BV-induced neurotoxicity by exposing human neuroblastoma cells (SH-SY5Y) to BV. It was found that SNHG12 and NLRX1 levels were gradually downregulated, while miR-497-5p enrichment was upregulated accordingly with the increase of BV concentration. As indicated by functional assays, SNHG12 overexpression promoted cell viability but inhibited cell apoptosis and oxidative stress in BV-treated SH-SY5Y cells. In addition, it was identified that SNHG12 directly targeted miR-497-5p and attenuated BV-induced neurotoxicity via interaction with miR-497-5p. Besides, it was confirmed that SNHG12 could upregulate NLRX1 expression by absorbing miR-497-5p. Moreover, miR-497-5p decreased cell viability and induced cell apoptosis and oxidative stress, which was partly reversed by NLRX1 upregulation. In conclusion, our findings indicated that SNHG12 might relieve BV-associated neurotoxicity by upregulating NLRX1 via miR-497-5p in vitro, providing novel clues and biomarkers for the treatment and prevention of BV-associated neurotoxicity.

Osthole-Mediated Inhibition of Neurotoxicity Induced by Ropivacaine via Amplification of the Cyclic Adenosine Monophosphate Signaling Pathway.

BackgroundRopivacaine is widely used for clinical anesthesia and postoperative analgesia. However, the neurotoxicity induced by ropivacaine in a concentration- and duration-dependent manner, and it is difficult to prevent neurotoxicity. Osthole inhibits phosphodiesterase-4 activity by binding to its catalytic site to prevent cAMP hydrolysis. The aim of this present study is to explore the precise molecular mechanism of osthole-mediated inhibition of neurotoxicity induced by ropivacaine.Methods:SH-SY5Y cell viability and apoptosis were measured in different concentration and duration. Protein concentration was determined in each signaling pathway. The molecular mechanism of osthole-mediated inhibition of ropivacaine-caused neurotoxicity was evaluated.ResultsThe study demonstrated that osthole inhibits SH-SY5Y cells neurotoxicity in a duration- and concentration-dependent manner. Moreover, ropivacaine significantly increased the expression of caspase-3 by promoting the phosphorylation of p38. Osthole-induced upregulation of cAMP activated cAMP-dependent signaling pathway, sequentially leading to elevated cyclic nucleotide response element-binding protein levels, which inhibits P38-dependent signaling and decreases apoptosis of SH-SY5Y.ConclusionsThis study display the evidence confirmed the molecular mechanism by which osthole amplification of cAMP-dependent signaling pathway, and overexpression of cyclic nucleotide response element-binding protein inhibits P38-dependent signaling and decreases ropivacaine-induced SH-SY5Y apoptosis.

Upregulated hexokinase 2 expression induces the apoptosis of dopaminergic neurons by promoting lactate production in Parkinson's disease

Parkinson's disease (PD) is characterized by impaired mitochondrial function and decreased ATP levels. Aerobic glycolysis and lactate production have been shown to be upregulated in dopaminergic neurons to sustain ATP levels, but the effect of upregulated glycolysis on dopaminergic neurons remains unknown. Since lactate promotes apoptosis and α-synuclein accumulation in neurons, we hypothesized that the lactate produced upon upregulated glycolysis is involved in the apoptosis of dopaminergic neurons in PD. In this study, we examined the expression of hexokinase 2 (HK2) and lactate dehydrogenase (LDH), the key enzymes in glycolysis, and lactate levels in the substantia nigra pars compacta (SNpc) of a MPTP-induced mouse model of PD and in MPP+-treated SH-SY5Y cells. We found that the expression of HK2 and LDHA and the lactate levels were markedly increased in the SNpc of MPTP-treated mice and in MPP+-treated SH-SY5Y cells. Exogenous lactate treatment led to the apoptosis of SH-SY5Y cells. Intriguingly, lactate production and the apoptosis of dopaminergic neurons were suppressed by the application of 3-bromopyruvic acid (3-Brpa), a HK2 inhibitor, or siRNA both in vivo and in vitro. 3-Brpa treatment markedly improved the motor behaviour of MPTP-treated mice in pole test and rotarod test. Mechanistically, lactate increases the activity of adenosine monophosphate-activated protein kinase (AMPK) and suppresses the phosphorylation of serine/threonine kinase 1 (Akt) and mammalian target of rapamycin (mTOR). Together, our data suggest that upregulated HK2 and LDHA and increased lactate levels prompt the apoptosis of dopaminergic neurons in PD. Inhibition of HK2 expression attenuated the apoptosis of dopaminergic neurons by downregulating lactate production and AMPK/Akt/mTOR pathway in PD.

Inhibitory Effect of CCK-8 on Methamphetamine-Induced Apoptosis.

To investigate the inhibitory effect of cholecystokinin octapeptide (CCK-8) binding to cholecystokinin 2 receptor (CCK2R) on methamphetamine (METH)-induced neuronal apoptosis, and to explore the signal transduction mechanism of β-arrestin 2 in CCK-8 inhibiting METH-induced neuronal apoptosis. SH-SY5Y cell line was cultured, and HEK293-CCK1R and HEK293-CCK2R cell line were constructed by lentivirus transfection. Small interfering RNA (siRNA) was used to knockdown the expression of β-arrestin 2. Annexin Ⅴ-FITC/PI staining and flow cytometry were used to detect the apoptotic rate of cells, and Western blotting was used to detect the expression of apoptosis-related proteins. The apoptosis of SH-SY5Y cells was induced by 1 mmol/L and 2 mmol/L METH treatment, the number of nuclear fragmentation and pyknotic cells was significantly increased, and the expression of apoptosis-related proteins Bax and cleaved caspase-3 were increased. CCK-8 pre-treatment at the dose of 0.1 mmol/L and 1 mmol/L significantly reversed METH-induced apoptosis in SH-SY5Y cells, and inhibited cell nuclear fragmentation, pyknosis and the changes of apoptosis-related proteins induced by METH. In lentivirus transfected HEK293-CCK1R and HEK293-CCK2R cells, the results revealed that CCK-8 had no significant effect on METH-induced changes of apoptosis-related proteins in HEK293-CCK1R cells, but it could inhibit the expression level of apoptosis-related proteins in HEK293-CCK2R cells induced by METH. The inhibitory effect of CCK-8 on METH-induced apoptosis was blocked by the knockdown of β-arrestin 2 expression in SH-SY5Y cells. CCK-8 can bind to CCK2R and exert an inhibitory effect on METH-induced apoptosis by activating the β-arrestin 2 signal.

Hibiscus Flower and Olive Leaf Extracts Activate Apoptosis in SH-SY5Y Cells

Compounds of natural origin may constitute an interesting tool for the treatment of neuroblastoma, the most prevalent extracranial solid tumor in children. PRES is a commercially available food supplement, composed of a 13:2 (w/w) extracts mix of Olea europaea L. leaves (OE) and Hibiscus sabdariffa L. flowers (HS). Its potential towards neuroblastoma is still unexplored and was thus investigated in human neuroblastoma SH-SY5Y cells. PRES decreased the viability of cells in a concentration-dependent fashion (24 h IC50 247.2 ± 31.8 µg/mL). Cytotoxicity was accompanied by an increase in early and late apoptotic cells (AV-PI assay) and sub G0/G1 cells (cell cycle analysis), ROS formation, reduction in mitochondrial membrane potential, and caspases activities. The ROS scavenger N-acetyl-L-cysteine reverted the cytotoxic effects of PRES, suggesting a key role played by ROS in PRES-mediated SH-SY5Y cell death. Finally, the effects of OE and HS extracts were singularly tested and compared to those of the corresponding mixture. OE- or HS-mediated cytotoxicity was always significantly lower than that caused by PRES, suggesting a synergic effect. In conclusion, the present findings highlight the potential of PRES for the treatment of neuroblastoma and offers the basis for a further characterization of the mechanisms underlying its effects.

Attenuation of the cytoprotection induced by hypoxic preconditioning upon transfection with BNIP3-siRNA in human neuroblastoma SH-SY5Y cells

Purpose The aim of this study was to investigate the functional role of hypoxic preconditioning (HPC) in human neuroblastoma cells. Methods BNIP3 small-interfering RNA (BNIP3-siRNA) sequence was synthesized and used to transfect human neuroblastoma SH-SY5Y cell lines. Thereafter, BNIP3 expression at mRNA and protein levels and its effects on the cell proliferation were analyzed. The most effective pair of siRNA was selected to knockdown the expression level of BNIP3. Moreover, the effects of HPC on oxygen-glucose deprivation/reperfusion (OGD/R)-induced apoptosis and autophagy in SH-SY5Y cells were explored to further reveal the possible mechanisms underlying HPC. Results BNIP3-siRNA attenuated the protective effects of HPC by decreasing the cell viability, increasing the enzymatic activity of caspase-3 and 9, increasing the rate of apoptosis, and increasing the protein expression level of activated caspase-3. Additionally, BNIP3-siRNA had no significant influence on the expression level of HIF-1α induced by HPC, while it substantially inhibited HPC-induced BNIP3/Beclin1 and autophagy. Conclusions HPC promoted autophagy through regulating BNIP3 to reduce OGD/R.

Protect Effects of Seafood-Derived Plasmalogens Against Amyloid-Beta (1-42) Induced Toxicity via Modulating the Transcripts Related to Endocytosis, Autophagy, Apoptosis, Neurotransmitter Release and Synaptic Transmission in SH-SY5Y Cells.

To investigate the underlying mechanisms of decreased plasmalogens (Pls) levels in neurodegenerative diseases, here the effects of seafood-derived Pls on undifferentiated and differentiated human SH-SY5Y neuroblastoma cells exposed to amyloid-β1–42 was analyzed. Transcriptional profiles indicated that a total of 6,581 differentially expressed genes (DEGs) were significantly identified among different experimental groups, and KEGG analysis indicated that these DEGs were related to AD, endocytosis, synaptic vesicle cycle, autophagy and cellular apoptosis. After Pls treatment, the striking expression changes of ADORA2A, ATP6V1C2, CELF6, and SLC18A2 mRNA strongly suggest that Pls exerts a beneficial role in alleviating AD pathology partly by modulating the neurotransmitter release and synaptic transmission at the transcriptional level. Besides these, GPCRs are also broadly involved in Pls-signaling in neuronal cells. These results provide evidence for supporting the potential use of Pls as an effective therapeutic approach for AD.

Fine particulate matter induces endoplasmic reticulum stress-mediated apoptosis in human SH-SY5Y cells

Exposure to ambient fine particulate matter (PM2.5) may contribute to brain injury, however, the molecular mechanisms have not yet been fully described. In this study, the human SH-SY5Y cells were treated with PM2.5 with different concentrations (0, 25, 100, and 250 μg/mL) for 24 h to investigate the cell apoptosis mediated by endoplasmic reticulum (ER) stress. The ratio of apoptosis, Ca2+ level, biomarkers of ER stress and apoptosis were determined. The results revealed that PM2.5 triggered the increase of apoptosis ratio and cellular Ca2+ levels. Compared with control, the expression of GRP78 and phosphorylation of IER1α and p38 were enhanced significantly in the cells under the conditions of PM2.5 exposure for activating ER stress signals. Besides, the key genes (CHOP/DR5/Caspase8/Caspase12) in ER stress-induced apoptosis signals were up-regulated after the PM2.5 treatment compared to the control. The results suggested PM2.5 induced apoptosis in SH-SY5Y cells by the stimulation of ER stress, which may be the potential mechanism of neurological diseases incurred by PM2.5.

Protective effect of EGb761 against Aβ1-42 -induced SHSY5Y cells injury and blood-brain barrier disruption via regulating Akt/Nrf2 signaling pathway

Purpose: Alzheimer’s disease (AD) is a common disease in the world caused by deposition in the brain parenchyma, accumulation of beta amyloid which leads to the blood brain barrier (BBB) disruption. Regardless of enough progress in the treatment of AD, the principal mechanism of BBB injury is yet not clear.Methods: In this study we examined the impact of EGb761on Aβ 1-42-induced SH-SY5Y cells in vitro model of AD. Cell viability was assessed by using MTT assay, flow cytometry was used to check the rate of cell apoptosis, ROS generation and BBB leakage was assessed by measuring the level of fluorescence in Aβ-induced SH-SY5Y cells using a reactive oxygen species kit assay and BBB permeability assay, and mRNA levels of Bax, Bcl-2, caspase-3 was measured by using RT-qPCR. Furthermore, western blot analysis was used to measure the protein expressions of Akt, Nrf2 and HO-1 in Aβ 1-42-induced SH-SY5Y cells.Results: The effect of EGb761 was investigated on the cell apoptosis induced by Aβ 1-42 andgeneration of ROS and we found that EGb761 plays a protective role against cell injury induced by Aβ 1-42. Cell apoptosis and ROS generation in SH-SY5Y cells decreased significantly with the treatment of EGb761. Furthermore, BBB permeability reduced considerably when the cells treated with EGb761 and the expression levels of Caspase-3 and Bax decreased while that of Bcl-2 were markedly increased in the Aβ 1-42-induced SH-SY5Y cells. Also, an increased in expression levels of p-Akt, Nrf2 (nucleus) and HO-1 was observed with the treatment of EGb761 in Aβ 1-42-induced SH-SY5Y cells.Conclusion: It can be concluded from these results that EGb761 could play a protective role byinhibiting apoptosis and protect Aβ 1-42-induced cell injury in vitro model of AD via activating Akt/Nrf2signaling pathway. Our study suggested that EGb761 might be a therapeutic agent for the preventionand treatment of AD.

Thioredoxin-1 mediates neuroprotection of Schisanhenol against MPP+-induced apoptosis via suppression of ASK1-P38-NF-\u03baB pathway in SH-SY5Y cells

Oxidative stress-induced dopaminergic neuronal loss and apoptosis play a crucial role in the pathogenesis of Parkinson’s disease (PD), and as a vital antioxidant protein, thioredoxin (Trx) exerts neuroprotection against PD. In this study, we investigated the effect of Schisanhenol (Sal), an active component from a traditional Chinese herb Schisandra rubriflora (Franch.), on MPP+-induced apoptosis and its association with thioredoxin-1 (Trx1) in SH-SY5Y cells. The protein levels of Trx1 and apoptosis-related proteins were detected by Western blot, the expression of Trx1 mRNA by real time qPCR, and apoptosis was detected by fluorescence microscopy and flow cytometry. Pretreatment with Sal (1 µM, 10 µM, and 50 µM) dose-dependently ameliorated MPP+-induced neuronal injury, confirmed by the improvement of the viability and morphological changes. Sal decreased the apoptosis rate of cells, suppressed the production of DNA ladder and sub-G1 peak, inhibited the Caspase-3 activity and the expression of apoptosis-related proteins. Sal enhanced the expression of Trx1 both in the protein and mRNA levels. However, the Trx1 inhibitor PX-12 suppressed the protective effects of Sal. In addition, Sal inhibited NF-κB translocation and activation. These results suggest that Sal has a protective effect against MPP+-induced apoptosis in SH-SY5Y cells via up-regulation of Trx1 expression and suppression of ASK1-P38-NF-κB pathway.

The effects of the renin inhibitor aliskiren on neuronal toxic damage.

The neurotoxicity of amyloid-β (Aβ) and its deposition in neurons plays a critical role in the occurrence and development of Alzheimer's disease (AD). Several preclinical experiments have found that the renin inhibitor aliskiren has a wide range of physiological effects, including hindering the progression of atherosclerosis and anti-inflammatory. This study is aimed to explore the effect of aliskiren on neuronal toxic damage and the underlying mechanism. This study established an in vitro nerve injury model through Aβ 1-42 induction; the effects of aliskiren on the viability, inflammatory damage and apoptosis of SH-SY5Y cells were examined. For the sake of explore the underlying mechanism; SwissTargetPrediction website and molecular docking were utilized to predict the target of aliskiren. Then the impacts of the target protein overexpression were determined to verify its mediation. The results of the current study demonstrate that aliskiren has no effect on the viability of SH-SY5Y cells while Aβ1-42accumulation could significantly downregulate cell viability. In addition, aliskiren could alleviate neuronal inflammatory damage and apoptosis arise from Aβ 1-42accumulation. Following confirming the high expression level of the predicted target PDE4B in damaged cells, it was found that PDE4B overexpression can reverse the influence of aliskiren on cell viability, inflammatory damage and apoptosis. In conclusion, aliskiren upregulates cell viability, reduces inflammatory damage and apoptosis induced by Aβ accumulation in AD via inhibiting PDE4B. These findings have expanded the scope of future application of aliskiren and provided a theoretical basis.

WITHDRAWN: β4 ameliorates oxidative damage and apoptosis through ERK/MAPK and 5-HT1A signaling pathway in Aβ insulted SH-SY5Y cells

Alzheimer's disease (AD) is the most common progressive neurodegenerative disorder seriously endangering the physical and mental health of the elderly, while no effective treatments and drugs in clinical practice are available. Thymosin β4 (Tβ4) is a multifunctional polypeptide involved in many physiological and pathological processes including AD. This study aims to understand the function and molecular mechanism of Tβ4 in the development of AD. Neuroblastoma cell line SH-SY5Y was treated with β-amyloid (Aβ) to induce AD-like pathological changes, which serves as Alzheimer's disease model. Tβ4 was overexpressed in SH-SY5Y cells by lentivirus infection, and downregulated by siRNA transfection. Apoptosis of transfected SH-SY5Y cells after Aβ-treatment was examined by western blot and flow cytometry. Apoptotic proteins and Tβ4-related signaling pathways were also investigated by western blot. We found that Tβ4 overexpression increased viability and suppressed apoptosis of Aβ-treated SH-SY5Y cells. Tβ4 ameliorated oxidative damage and suppressed reactive oxygen species production in Aβ-treated SH-SY5Y cells. Consistently, Tβ4 overexpression down-regulated the expression levels of pro-apoptotic markers such as Caspase-3, Caspase-8, and Bax, while up-regulated the expression level of anti-apoptotic gene Bcl-2 in Aβ-stimulated SH-SY5Y cells. Mechanistically, we demonstrated that Tβ4 dampened ERK/p38 MAPK signaling and enhanced 5-HTR1A expression in Aβ-treated SH-SY5Y cells. Moreover, we revealed that Tβ4 inhibited the activation of ERK pathway through up-regulating 5-HTR1A in Aβ-treated SH-SY5Y cells. Taken together, our findings provide evidences to support the neuroprotective role of Tβ4 and might open up new therapeutic applications of Tβ4 in AD treatment.

Magnolol upregulates CHRM1 to attenuate Amyloid-β-triggered neuronal injury through regulating the cAMP/PKA/CREB pathway.

Alzheimer's disease (AD) is a common neurodegenerative disease characterized by neuronal degeneration and hyperphosphorylated Tau. Magnolol is an active component isolated from Magnolia officinalis with potential neuroprotection activity. However, the function and mechanism of magnolol in AD progression is largely uncertain. In present study, the biomarkers related to AD and magnolol were predicted by bioinformatics analyses. The key biomarker levels were predicted by GSE5281 and GSE36980 using AlzData. Cell viability was detected by CCK-8 assay. mRNA and protein levels were examined by qRT-PCR and western blotting assays. Cell apoptosis was investigated by caspase-3 activity and flow cytometry analyses. The cAMP/PKA/CREB signaling was evaluated by ELISA and western blotting analyses. The results showed that CHRM1 was a key biomarker for magnolol against AD progression. Magnolol attenuated Aβ-induced viability inhibition, Tau hyperphosphorylation and apoptosis in SH-SY5Y cells by upregulating CHRM1. In addition, the cAMP signaling might be a potential pathway of CHRM1 in AD. Magnolol contributed to activation of the cAMP/PKA/CREB pathway through enhancing CHRM1 level. Inactivation of the cAMP/PKA/CREB signaling reversed the suppressive effect of magnolol on Tau hyperphosphorylation and apoptosis in Aβ-treated SH-SY5Y cells. As a conclusion, magnolol mitigated Aβ-induced Tau hyperphosphorylation and neuron apoptosis by upregulating CHRM1 and activating the cAMP/PKA/CREB pathway.

Neuroprotective effect of bromelain in 6-hydroxydopamine induced in vitro model of Parkinson's disease.

This study was designed to investigate the neuroprotective effects of bromelain, which is known to have anti-oxidant and anti-inflammatory properties, against the neurotoxicity (induced by 6-OHDA) in SH-SY5Y cells. To establish Parkinson's Disease (PD) model in cell culture conditions, SH-SY5Y cells were exposed to 200 µM 6-OHDA for 1day. Prior to 6-OHDA treatment, SH-SY5Y cells had been pre-treated with bromelain (25µg/mL, 50µg/mL, 75µg/mL and 100µg/mL). After 1day, cell viability was determined with the 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) and lactate dehydrogenase (LDH) assays. Oxidative stress was assessed with total antioxidant capacity (TAC), total oxidant status (TOS), glutathione reductase (GR) and malondialdehyde (MDA) analyses. The effect of the bromelain in SH-SY5Ycells was also examined by 4',6-diamidino-2-phenylindole (DAPI) staining. We found that 6-OHDA increased LDH leakage, and cellular apoptosis in SH-SY5Y cells. 6-OHDA aggravated oxidative stress by increasing TOS, MDA and GR and eventually promoted apoptosis in SH-SY5Y cells, while pretreatment with bromelain attenuated these toxic effects of 6-OHDA. These findings indicated that bromelain, with its neuroprotective features can be useful for neuroprotection in PD.

Downregulation of lncRNA MEG3 is involved in Parkinson's disease.

Long non-coding RNA (lncRNA) MEG3 regulates human cancers, while its role in Parkinson's disease (PD) is unknown. The present study explored the involvement of MEG3 in PD. This study enrolled PD patients (n = 79) and healthy controls (n = 62) who were admitted to the Second Affiliated Hospitalof Nanchang University from May 2016 to March 2018. RT-qPCR was performed to measure the expression of MEG3 and LRRK2. ROC curve analysis was performed for diagnostic analysis. Cell transfections were performed to analyze the interaction between MEG3 and LRRK2. Cell apoptosis and MTT assays were performed to evaluate the effect of cell transfections on cell apoptosis and viability. MEG3 was downregulated in PD patients compared to that in the healthy controls. ROC curve analysis showed altered expression of MEG3 in PD patients. MEG3 was also down-regulated in SH-SY5Y cells treated with MPP + . Overexpression of MEG3 increased the expression levels of leucine-rich repeat kinase 2 (LRRK2) in SH-SY5Y cells. In contrast, overexpression of LRRK2 showed no significant effects on MEG3. Overexpression of MEG3 improved the viability and inhibited the apoptosis of SH-SY5Y cells pretreated with MPP + . In conclusion, lncRNA MEG3 is downregulated in PD and may affect the expression of LRRK2 to regulate cell viability and apoptosis involved in PD.