Activity In SH-SY5Y Cells Research Articles

Rational Search for Betaine/GABA Transporter 1 Inhibitors─In Vitro Evaluation of Selected Hit Compound.

Inhibitory neurotransmission mediated by γ-aminobutyric acid (GABA) plays an important role in maintaining body homeostasis. Disturbances in GABA signaling are implicated in a multitude of neurologic and psychiatric conditions, including epilepsy, ischemia, anxiety, depression, insomnia, and mood disorders. Clinically relevant increases in GABA neurotransmitter level can be achieved by inhibition of its uptake into presynaptic neurons and surrounding glial cells, driven by GABA transporters (GAT1, BGT1, GAT2, and GAT3). Herein, we focused on the search for inhibitors of the BGT1 transporter which is understudied and for which the therapeutic potential of its inhibition is partly unknown. We applied multilevel virtual screening to identify compounds with inhibitory properties. Among selected hits, compound 9 was shown to be a preferential inhibitor of BGT1 (IC50 13.9 μM). The compound also revealed some inhibitory activity against GAT3 (4x lower) while showing no or low activity (IC50 > 100 μM) toward GAT1 and GAT2, respectively. The predicted binding mode of compound 9 was confirmed by mutagenesis studies on E52A, E52Y, Q299L, and E52A+Q299L human BGT1 mutants. Subsequent evaluation showed that the selected hit displayed no affinity toward major GABAA receptor subtypes. Moreover, it was nontoxic when tested on normal human astrocytes and even showed some neuroprotective activity in SH-SY5Y cells. Compound 9 is considered a promising candidate for further evaluation of the therapeutic potential of BGT1 transporter inhibition and the development of novel inhibitors.

Metabolites of Culinary-medicinal Mushroom Hericium erinaceus Showed Anti-neuroinflammatory Activity in BV2 Cells and Anti-H2O2-induced Oxidative Stress Activity in SH-SY5Y Cells

Background: Hericium erinaceus is a versatile mushroom with potential therapeutic benefits. A variety of bioactive compounds have been found in this mushroom that have anti-ulcer, antiinflammatory, immunomodulatory, and blood sugar and lipid regulating effects. Objectives: The aim is to isolate and characterize compounds from the rice medium of H. erinaceus and evaluate their potential therapeutic effects on oxidative stress-associated diseases. Methods: Fifteen compounds were isolated and characterized using NMR spectra and ESI-MS. The effects of compounds 3 and 7 on LPS-induced nitric oxide (NO) generation in BV2 cells and H2O2- induced cytotoxicity in SH-SY5Y cells were investigated. The regulation of nitric oxide production and apoptosis-associated proteins Bcl-2 and Bax were also examined. Results: Compounds 3 and 7 exhibited potent inhibitory effects on LPS-induced NO generation in microglial cells and significant resistance to H2O2-induced cytotoxicity in neuronal cells. Molecular docking simulations demonstrated the interaction of compounds 3 and 7 with iNOS and Bax, respectively. Western blot analysis revealed that 7 inhibited NO production and regulated the expression of Bax and Bcl-2, suggesting a protective effect against H2O2-induced apoptosis. Conclusion: Compounds 3 and 7 isolated from H. erinaceus are potential therapeutic candidates for oxidative stress-associated diseases, possibly through their regulation of nitric oxide production and apoptosis-related proteins. Further investigations are warranted to elucidate their mechanisms of action and therapeutic potential.

The intracellular monoamine oxidase-A inhibitory activity and the protective effect of small hairtail-related peptides in nerve cells (SH-SY5Y).

This study was to investigate the inhibitory activity of small hairtail-related peptides (VFEVFW, LPNSLYQQ, LPNSLYQK, and FADAME) on intracellular monoamine oxidase-A (MAO-A) and their protective effects in a cell model. Specifically, the inhibition activity in SH-SY5Y cells indicated that VFEVFW and LPNSLYQK reduced ∼50% of MAO-A activity in cells, at 0.5m m. The survival experiment demonstrated that the toxic effect of dexamethasone (DEX) on cells can be significantly alleviated in the presence of peptides, and these peptides can restore (>20%) the mitochondrial membrane potential of SH-SY5Y cells reduced by DEX. Circular dichroism displayed that peptides affected the secondary structure of MAO-A in a concentration-dependent manner. Finally, the real-time quantitative polymerase chain reaction assay revealed that the MAO-A inhibitory activity of the peptides was associated with the upregulation of brain derived neurotrophic factor/cAMP (Cyclic adenosine monophosphate) response element binding protein)/B-cell lymphoma-2 mRNA levels.

P21-11: Synthetic Cannabinoids and senescence markersi n vitro: impact on cell proliferation, influence of cannabinoid receptors, and beta-galactosidase activity in SH-SY5Y cells

P21-11: Synthetic Cannabinoids and senescence markersi n vitro: impact on cell proliferation, influence of cannabinoid receptors, and beta-galactosidase activity in SH-SY5Y cells

Aronia juice improves working memory and suppresses δ-secretase activity in 5XFAD mice

Asparagine endopeptidase (AEP) cleaves amyloid precursor protein to facilitate amyloid β (Aβ) production in the brain. Aronia berry (Aronia melanocarpa) has various beneficial effects on health through inhibition of enzymes such as dipeptidyl peptidase IV. In this study, to examine neuroprotective effects of aronia juice (AJ), AJ was given to male 5XFAD Alzheimer's disease model mice via drinking bottles over a period from 2 weeks to 12 weeks of age. AJ intake improved the performance of Y-maze test in 5XFAD mice, and suppressed the δ-secretase activity in the mouse brains. AJ intake reduced significantly Aβ deposition in the brain. AJ reduced δ-secretase activity in human neuroblastoma SH-SY5Y cells. Out of five fractions (F1–F5) obtained from AJ, only F5 reduced δ-secretase activity in SH-SY5Y cells in a dose-dependent manner. LC-MS/MS analysis suggested that F5 contains three quercetin glycosides. AJ has neuroprotective function through inhibition of δ-secretase activity of AEP.

Heme and Cu2+-induced vasoactive intestinal peptide (VIP) tyrosine nitration: A possible molecular mechanism for the attenuated anti-inflammatory effect of VIP in inflammatory diseases

Vasoactive intestinal peptide (VIP) is a neuropeptide that play an important role in immunoregulation and anti-inflammation. Numerous inflammatory/autoimmune disorders are associated with decreased VIP binding ability to receptors and diminished VIP activation of cAMP generation in immune cells. However, the mechanisms linking oxidative/nitrative stress to VIP immune dysfunction remain unknown. It has been reported that the elevated heme or Cu2+ in inflammatory diseases can cause oxidative and nitrative damage to nearby biological targets under high oxidative stress conditions, which affects the structure and activity of linked peptides or proteins. Thus, the VIP down-regulated immune response may be interfered by redox metal catalyzed VIP tyrosine nitration. To explore this, we systematically investigated the possibility of heme or Cu2+ to catalyze VIP tyrosine nitration. The results showed that Tyr10 and Tyr22 of VIP can both be nitrated in heme/H2O2/NO2− system as well as in Cu2+/H2O2/NO2− system. Then, we used synthetic mutant VIPs with tyrosine residues substituted by 3-nitrotyrosine to study the impact of tyrosine nitration on VIP activity in SHSY-5Y cells. Our findings demonstrated that VIP nitration dramatically decreased the content of its α-helix and random coil, suggesting that VIP nitration might reduce its affinity to the receptor. This was further confirmed in the cAMP assay. The results showed that 10 nM of these tyrosine nitrated VIPs could significantly (p < 0.01) decrease cAMP secretion compared to the wild type VIP. Our data reveal that the attenuation of the neuroprotective effect of VIP in inflammation-related diseases might be attributed to metal-catalyzed VIP tyrosine nitration.

Ipconazole Induces Oxidative Stress, Cell Death, and Proinflammation in SH-SY5Y Cells.

Ipconazole is an antifungal agrochemical widely used in agriculture against seed diseases of rice, vegetables, and other crops; due to its easy accumulation in the environment, it poses a hazard to human, animal, and environmental health. Therefore, we investigated the cytotoxic effect of ipconazole on SH-SY5Y neuroblastoma cells using cell viability tests (MTT), ROS production, caspase3/7 activity, and molecular assays of the biomarkers of cell death (Bax, Casp3, APAF1, BNIP3, and Bcl2); inflammasome (NLRP3, Casp1, and IL1β); inflammation (NFκB, TNFα, and IL6); and antioxidants (NRF2, SOD, and GPx). SH-SY5Y cells were exposed to ipconazole (1, 5, 10, 20, 50, and 100 µM) for 24 h. The ipconazole, in a dose-dependent manner, reduced cell viability and produced an IC50 of 32.3 µM; it also produced an increase in ROS production and caspase3/7 enzyme activity in SH-SY5Y cells. In addition, ipconazole at 50 µM induced an overexpression of Bax, Casp3, APAF1, and BNIP3 (cell death genes); NLRP3, Casp1, and IL1B (inflammasome complex genes); and NFκB, TNFα, and IL6 (inflammation genes); it also reduced the expression of NRF2, SOD, and GPx (antioxidant genes). Our results show that ipconazole produces cytotoxic effects by reducing cell viability, generating oxidative stress, and inducing cell death in SH-SY5Y cells, so ipconazole exposure should be considered as a factor in the presentation of neurotoxicity or neurodegeneration.

Effects of nourishing qi, activating blood circulation, and inducing resuscitation on nerve cell pyroptosis after cerebral ischemia-reperfusion

Cerebral ischemia-reperfusion (CIR) is a serious complication often associated with cerebral ischemia. The purpose of this study was to explore the therapeutic effect of nourishing qi, activating blood circulation, and inducing resuscitation (Borneol with astragaloside IV and Panax notoginseng total saponins, BAP) on CIR. Neurological function score system was used to determine the neurological function. The survival of nerve cells was detected by Nissl staining. The levels of IL-1β, IL-18, IL-4, and IL-10 were detected by ELISA. The expression of GSDMD, GSDMD-N, Nrf2, and HO-1 proteins in hippocampus tissues was measured by immunohistochemistry (IHC). Western blot, RT-qPCR, or immunofluorescence (IF) were used to detect the NACHT, LRR, and PYD domains-containing protein 3 (NLRP3), pro-Caspase-1, Caspase-1, Nrf2, and HO-1 expression. Lactate dehydrogenase (LDH) level was analyzed by LDH release assay. Cell viability was determined by cell counting kit-8 (CCK8). Apoptosis was detected by flow cytometry. BAP significantly promoted the recovery of nerve function, the activity of nerve cells, and the expression of Nrf2, HO-1, IL-4, and IL-10 in rat hippocampus tissues after CIR. BAP has an obvious inhibitory effect on the expression of NLRP3, pro-Caspase-1, and Caspase-1 proteins, the release of IL-1β and IL-18 factors, and neuronal pyroptosis in hippocampal tissues. BAP also promoted IL-4 and IL-10 levels, and the activity of SH-SY5Y cells. The IL-1β, IL-18, NLRP3, pro-Caspase-1, Caspase-1, GSDMD, and GSDMD-N expressions were significantly inhibited by BAP in vitro, which was reversed by Nrf2 knockdown. This study confirmed that BAP alleviated rat CIR and inhibited the pyroptosis of SH-SY5Y cells by regulating the Nrf2/HO-1 signaling pathway. This study provided new directions and ideas for the treatment of CIR.

Ameliorative Effect of Medicarpin on Scopolamine-Induced Cognitive Impairment in Mice

The ameliorative effect of medicarpin (MC) was investigated by animal behavioral experiments such as Morris water maze (MWM), Y-maze, and passive avoidance test (PAT), using scopolamine-induced cognitively impaired mice. The scopolamine (5 mg/kg), donepezil (5 mg/kg), and MC (5 and 15 mg/kg) were administered by intraperitoneal injection at a volume of 0.3 mL. In the MWM, the escape latency times of MC-treated groups were significantly decreased compared with the scopolamine-treated negative control, and times spent in the platform zone of MC-treated groups were increased dose-dependently. In the Y-maze, the zone alternations of the MC-treated group were increased to the level of the donepezil-treated positive control. In the PAT, the crossing times of MC-treated groups were significantly higher than those of the negative control with dose-dependency. On the other hand, the monoamine oxidase (MAO)-A, MAO-B, and acetylcholinesterase (AChE) activities, relating to cognitive functions, in hippocampus treated with MC were decreased. In addition, the AChE activity in SH-SY5Y cells was significantly decreased. In Western blots, phosphorylated cyclic adenosine monophosphate (cAMP) response element-binding protein (p-CREB), brain-derived neurotrophic factor (BDNF), phosphorylated protein kinase B (p-Akt), and dopamine D2 receptor (D2R) levels in the hippocampus were higher than those of the negative control. In addition, p-CREB, BDNF, p-Akt, and D2R levels in SH-SY5Y cells treated with MC were significantly increased. These results showed that MC ameliorated a cognitive function along with increased BDNF and D2R expressions, and they suggested that MC could be used for the treatment of neurological disorders such as Alzheimer’s disease and Parkinson’s disease.

Effects of Different Opioid Drugs on Oxidative Status and Proteasome Activity in SH-SY5Y Cells.

Opioids are the most effective drugs used for the management of moderate to severe pain; however, their chronic use is often associated with numerous adverse effects. Some results indicate the involvement of oxidative stress as well as of proteasome function in the development of some opioid-related side effects including analgesic tolerance, opioid-induced hyperalgesia (OIH) and dependence. Based on the evidence, this study investigated the impact of morphine, buprenorphine or tapentadol on intracellular reactive oxygen species levels (ROS), superoxide dismutase activity/gene expression, as well as β2 and β5 subunit proteasome activity/biosynthesis in SH-SY5Y cells. Results showed that tested opioids differently altered ROS production and SOD activity/biosynthesis. Indeed, the increase in ROS production and the reduction in SOD function elicited by morphine were not shared by the other opioids. Moreover, tested drugs produced distinct changes in β2(trypsin-like) and β5(chymotrypsin-like) proteasome activity and biosynthesis. In fact, while prolonged morphine exposure significantly increased the proteolytic activity of both subunits and β5 mRNA levels, buprenorphine and tapentadol either reduced or did not alter these parameters. These results, showing different actions of the selected opioid drugs on the investigated parameters, suggest that a low µ receptor intrinsic efficacy could be related to a smaller oxidative stress and proteasome activation and could be useful to shed more light on the role of the investigated cellular processes in the occurrence of these opioid drug side effects.

Valproic acid upregulates sodium-dependent vitamin C transporter-2 functional expression in neuronal cells

Neuronal uptake of ascorbic acid (AA) in humans occurs via the human sodium-dependent vitamin C transporter-2 (hSVCT2). Recent studies show that a significantly lower level of vitamin C is present in the blood of epileptic patients. Consequently, focused studies investigating the involved molecular mechanisms for hSVCT2 regulation are vital to enhance vitamin C body homeostasis. Currently, little is known about the role of valproic acid (VPA), a drug utilized to treat epilepsy and a class I histone deacetylase inhibitor (HDACi), on AA uptake in neuronal systems. Thus, this study aims to examine the effect of VPA on hSVCT2 functional expression in neuronal cells. VPA treatment upregulated the AA uptake and this increased AA uptake was associated with a significant increase in hSVCT2 expression and SLC23A2 promoter activity in SH-SY5Y cells. Knockdown of HDAC2, a predominant isoform in neuronal systems, significantly increased hSVCT2 functional expression. VPA treatment in mice displayed increased mouse (m)SVCT2 protein, mRNA and heterogenous nuclear RNA (hnRNA) expression in the brain. In addition, Yin Yang-1 (YY1), a transcription factor that drives the SLC23A2 promoter activity, protein and mRNA expression levels were markedly upregulated in VPA-treated SH-SY5Y cells and mice brain. Together, our findings suggest that VPA upregulates the functional expression of SVCT2 via HDAC2 and transcriptional mechanism(s).

A Pretreatment with Isoorientin Attenuates Redox Disruption, Mitochondrial Impairment, and Inflammation Caused by Chlorpyrifos in a Dopaminergic Cell Line: Involvement of the Nrf2/HO-1 Axis.

The C-glucosyl flavone isoorientin (ISO) is obtained by humans from the diet and exhibits several cytoprotective effects, as demonstrated in different experimental models. However, it was not previously shown whether ISO would be able to prevent mitochondrial impairment in cells exposed to a chemical stressor. Thus, we treated the human neuroblastoma SH-SY5Y cells with ISO (0.5-20µM) for 18h before a challenge with chlorpyrifos (CPF) at 100µM for additional 24h. We observed that ISO prevented the CPF-induced lipid peroxidation and protein carbonylation and nitration in the membranes of mitochondria extracted from CPF-treated cells. ISO also attenuated the CPF-elicited increase in the production of reactive species in this experimental model. Moreover, ISO prevented the CPF-induced disruption in the activity of components of the oxidative phosphorylation (OXPHOS) system in the SH-SY5Y cells. ISO also promoted an anti-inflammatory action in the cells exposed to CPF. CPF caused a decrease in the activity of the enzyme heme oxygenase-1 (HO-1), a cytoprotective agent. On the other hand, ISO upregulated HO-1 activity in SH-SY5Y cells. Inhibition of HO-1 by zinc protoporphyrin-IX (ZnPP-IX) suppressed the cytoprotection induced by ISO in the CPF-treated cells. Besides, silencing of the transcription factor nuclear factor erythroid 2-related factor 2 (Nrf2) abolished the ISO-induced HO-1 upregulation and mitochondrial benefits induced by this flavone on the CPF-challenged cells. Thus, ISO protected mitochondria of the CPF-treated cells by an Nrf2/HO-1-dependent fashion in the SH-SY5Y cells.

DNSP‐11 reduces 6‐OHDA‐induced caspase 3/7 activation in an SH‐SY5Y cell model: Potential Role of ERK signaling pathway?

Glial cell line‐derived neurotrophic factor (GDNF) has been shown to be a promising therapeutic molecule for treating Parkinson’s disease (PD). However, because of the failure of GDNF infusion in clinical trials, due to its poor bio‐distribution, there was a need to develop other molecules with similar properties to GDNF that have improved bioavailability and administration. Dopamine neuron stimulating peptide‐11 (DNSP‐11) is a synthetic, amidated 11‐amino acid neuroactive peptide derived from the human proGDNF domain. DNSP‐11 has been shown to protect dopaminergic cells in vitro and restore dopaminergic activity in vivo. Therefore, the objective of our study was to test if DNSP‐11 protects human dopaminergic neuroblastoma SH‐SY5Y cells against 6‐OHDA induced toxicity and to elucidate the protective mechanism of action. DNSP‐11 reduced the 6‐OHDA–induced increase in caspase‐3/7 activity in SH‐SY5Y cells at early time points, indicating possible protection against apoptosis. DNSP‐11 also activated the cell survival signaling pathways, ERK1, 2, and 5 in SH‐SY5Y cells. In addition, a single injection of DNSP‐11 in adult rat striatum leads to modulation of these ERK proteins in the substantia nigra. Overall, the results indicate that DNSP‐11 protects human dopaminergic neuroblastoma cells against apoptotic cell death and activates neuroprotective ERK signaling pathways, suggesting its potential therapeutic role in Parkinson’s disease (PD).

Cryptotanshinone ameliorates MPP+-induced oxidative stress and apoptosis of SH-SY5Y neuroblastoma cells: the role of STAT3 in Parkinson's disease.

Cryptotanshinone (CTN) has shown its neuroprotective and anti-inflammatory qualities in non-genetic mouse model of Alzheimer's disease. According to bioinformatics analysis, CTN and Signal Transducer and Activator of Transcription 3 (STAT3) may interact to form a drug-target network. This study was conducted to identify the role of CTN-STAT3 interaction in Parkinson's disease (PD). PD model was established with MMP+-stimulated SH-SY5Y cells. After pre-treatment with CTN or co-treatment with CTN and STAT3 agonist, MTT assay was performed to observe cell viability; ELISA kit was used to measure the expression level of pro-inflammatory cytokines; DCFH-DA and corresponding assay kits were employed to determine the production of ROS, SOD, CAT and GSH-px; TUNEL assay and western blot were performed to detect cell apoptosis. STAT3 activity was also detected by western blot. Treatment with CTN alone had no impact on SH-SY5Y cell viability, but CTN pre-treatment effectively improved MPP+-induced loss of viability in SH-SY5Y cells. Moreover, pre-treatment with CTN inhibited MPP+-induced oxidative stress, apoptosis and STAT3 activity in SH-SY5Y cells, whereas this inhibitory effect was diminished after additional treatment with STAT3 agonist. CTN ameliorates MPP+-induced oxidative stress and apoptosis of SH-SY5Y neuroblastoma cells by inhibiting the expression of STAT3. Therefore, CTN could be a promising therapeutic agent, and STAT3 could be a potential target for PD treatment.

Effect of amyloid-β on the redox system activity in SH-SY5Y cells preincubated with lipopolysaccharide or co-cultured with microglia cells

Amyloid deposits and hyperphosphorylation of the tau protein are still believed to be the two main causes of Alzheimer’s disease. However, newer studies show the beneficial (including antiradical and antimicrobial) effects of amyloid at physiological concentrations. Therefore, this study aimed to investigate the impact of three amyloid fragments – 25–35, 1–40, and 1–42 at concentrations close to physiological levels on the oxidative stress induced by the administration of lipopolysaccharide (LPS) or co-culturing with microglia cells. Differentiated SH-SY5Y cells were used, constituting a model of neuronal cells that were preincubated with LPS or supernatant collected from THP-1 cell culture. The cells were treated with amyloid-β fragments at concentrations of 0.001, 0.1, and 1.0 µM, and then biological assays were carried out. The results of the study support the antioxidant properties of Aβ, which may protect neurons from the damaging effects of neuroinflammation. All tested amyloid-β fragments reduced oxidative stress and increased the levels of enzymatic stress parameters – the activity of SOD, GPx and catalase. In addition, the administration of amyloid-β at low physiological concentrations also increased reduced glutathione (GSH) levels and the ratio between reduced and oxidized glutathione (GSH/GSSG), which is considered a good indicator of maintaining cellular redox balance. Furthermore, a stronger antioxidant effect of 1–40 fragment was observed, occurring in a wider range of concentrations, compared to the other tested fragments 25–35 and 1–42.

Calcium-Mediated Calpain Activation and Microtubule Dissociation in Cell Model of Hereditary Sensory Neuropathy Type-1 Expressing V144D SPTLC1 Mutation.

Hereditary sensory neuropathy type 1A (HSN1A) is an autosomal, dominantly inherited peripheral neuropathy caused by mutations in serine palmitoyl transferase long chain 1 (SPTLC1), involved in the de novo synthesis of sphingolipids. We have previously reported calcium imbalance, as well as mitochondrial and ER stress in both HSN1 patient lymphoblasts and a transiently transfected cell model. In this study, we investigated the role of the Ca2+-activated protease calpain in destabilizing the cell cytoskeleton, by examining calpain activity in SH-SY5Y cells overexpressing the V144D mutant and changes in microtubule-associated proteins (MAP). Intramitochondrial Ca2+ was found to be significantly depleted and cytoplasmic Ca2+ increased in the V144D mutant. Subsequently, calpain and proteasome activity were increased and calpain substrates, microtubule associated proteins MAP2, and tau were significantly reduced in the microtubule fraction of the mutant. Significant changes were also found in motor proteins dynein and KIF2A detected in the microtubule fraction of cells overexpressing the V144D mutation. There was also a reduction in anterograde and retrograde mitochondrial transport velocities in the V144D mutant. These findings strongly implicate cytoskeletal aberration caused by Ca2+ dysregulation and subsequent loss of microtubule transport functions as the cause of axonal dying back that is characteristic of HSN1.

Induction of Sirtuin1 Activity in SH-SY5Y Cells by Cyanidin-3-O-Glucocide Induced

An increase in oxidative stress plays a key role in neurotoxicity induction and cell death, which leads to neurodegenerative diseases such as Parkinson’s disease and Alzheimer’s disease. Cyanidin-3-glucoside (C3G) is a common anthocyanin and shows antioxidant activity in neuronal cells. Silent information regulator 2-related protein 1 (Sirt1) regulates antioxidant and anti-inflammatory effects. However, the effects of C3G on Sirt1 in neuronal cells remain unclear. This study evaluated the effect of C3G on Sirt1 expression and activity in human neuroblastoma (SH-SY5Y) cells. In the study, C3G increased the expression of Sirt1 and Sirt1 activity in SH-SY5Y cells. Additionally, C3G increased the expression of nuclear factor erythroid 2-related factor 2, a vital transcription factor for regulating the expression of antioxidant genes, as well as antioxidant enzymes such as superoxide dismutase and catalase. Moreover, C3G protected SH-SY5Y cells from oxidative stress. These results suggest that C3G decreased oxidative stress-induced cell injury by increasing the expression of Sirt1 and other antioxidant factors. Therefore, C3G might merit further investigation for use in attenuating the progress of neurodegenerative diseases.

Downregulation of aromatase by siRNA decreases acetylcholinesterase mRNA and specific activity in SHSY5Y cells

Downregulation of aromatase by siRNA decreases acetylcholinesterase mRNA and specific activity in SHSY5Y cells

CPEB1, a novel risk gene in recent-onset schizophrenia, contributes to mitochondrial complex I defect caused by a defective provirus ERVWE1.

BACKGROUNDSchizophrenia afflicts 1% of the world population. Clinical studies suggest that schizophrenia patients may have an imbalance of mitochondrial energy metabolism via inhibition of mitochondrial complex I activity. Moreover, recent studies have shown that ERVWE1 is also a risk factor for schizophrenia. Nevertheless, there is no available literature concerning the relationship between complex I deficits and ERVWE1 in schizophrenia. Identifying risk factors and blood-based biomarkers for schizophrenia may provide new guidelines for early interventions and prevention programs. AIMTo address novel potential risk factors and the underlying mechanisms of mitochondrial complex I deficiency caused by ERVWE1 in schizophrenia. METHODSQuantitative polymerase chain reaction (qPCR) and enzyme-linked immunosorbent assay were used to detect differentially expressed risk factors in blood samples. Clinical statistical analyses were performed by median analyses and Mann-Whitney U analyses. Spearman’s rank correlation was applied to examine the correlation between different risk factors in blood samples. qPCR, western blot analysis, and luciferase assay were performed to confirm the relationship among ERVWE1, cytoplasmic polyadenylation element-binding protein 1 (CPEB1), NADH dehydrogenase ubiquinone flavoprotein 2 (NDUFV2), and NDUFV2 pseudogene (NDUFV2P1). The complex I enzyme activity microplate assay was carried out to evaluate the complex I activity induced by ERVWE1. RESULTSHerein, we reported decreasing levels of CPEB1 and NDUFV2 in schizophrenia patients. Further studies showed that ERVWE1 was negatively correlated with CPEB1 and NDUFV2 in schizophrenia. Moreover, NDUFV2P1 was increased and demonstrated a significant positive correlation with ERVWE1 and a negative correlation with NDUFV2 in schizophrenia. In vitro experiments disclosed that ERVWE1 suppressed NDUFV2 expression and promoter activity by increasing NDUFV2P1 level. The luciferase assay revealed that ERVWE1 could enhance the promoter activity of NDUFV2P1. Additionally, ERVWE1 downregulated the expression of CPEB1 by suppressing the promoter activity, and the 400 base pair sequence at the 3′ terminus of the promoter was the minimum sequence required. Advanced studies showed that CPEB1 participated in regulating the NDUFV2P1/NDUFV2 axis mediated by ERVWE1. Finally, we found that ERVWE1 inhibited complex I activity in SH-SY5Y cells via the CPEB1/NDUFV2P1/NDUFV2 signaling pathway. CONCLUSIONIn conclusion, CPEB1 and NDUFV2 might be novel potential blood-based biomarkers and pathogenic factors in schizophrenia. Our findings also reveal a novel mechanism of ERVWE1 in the etiology of schizophrenia.

Exposure to PM2.5 induces neurotoxicity, mitochondrial dysfunction, oxidative stress and inflammation in human SH-SY5Y neuronal cells

Ambient air pollution is a global public health issue. Recent evidence suggests that exposure to fine aerosolized particulate matter (PM) as small as ≤2.5 microns (PM2.5) is neurotoxic to brain structures. Many studies also suggest exposure to PM2.5 may cause neurotoxicity and affect brain function. However, the molecular mechanisms by which PM2.5 exerts these effects are not fully understood. Thus, we evaluated the hypothesis that PM2.5 exposure exerts its neurotoxic effects via increased oxidative and inflammatory cellular damage and mitochondrial dysfunction using human SH-SY5Y neuronal cells. Here, we show PM2.5 exposure significantly decreases viability, and increases caspase 3 and 9 protein expression and activity in SH-SY5Y cells. In addition, PM2.5 exposure decreases SH-SY5Y survival, disrupts cell and mitochondrial morphology, and significantly decreases ATP levels, D-loop levels, and mitochondrial mass and function (maximal respiratory function, COX activity, and mitochondrial membrane potential) in SH-SY5Y cells. Moreover, SH-SY5Y cells exposed to PM2.5 have significantly decreased mRNA and protein expression levels of survival genes (CREB and Bcl-2) and neuroprotective genes (PPARγ and AMPK). We further show SH-SY5Y cells exposure to PM2.5 induces significant increases in the levels of oxidative stress, and expression levels of the inflammatory mediator’s TNF-α, IL-1β, and NF-κB. Taken together, these results provide the first evidence of the biochemical, molecular and morphological effects of PM2.5 on human neuronal SH-SY5Y cells, and support our hypothesis that increased mitochondrial disruption, oxidative stress and inflammation are critical mediators of its neurotoxic effects. These findings further improve our understanding of the neuronal cell impact of PM2.5 exposure, and may be useful in the design of strategies for the treatment and prevention of human neurodegenerative disorders.