Effects of barakol from Cassia siamea on neuroblastoma SH-SY5Y cell line: A potential combined therapy with doxorubicin.

Management of neuroblastoma is challenging because of poor response to drugs, chemotherapy resistance, high relapse, and treatment failures. Doxorubicin is a potent anticancer drug commonly used for neuroblastoma treatment. However, doxorubicin induces considerable toxicities, particularly those caused by oxidative-related damage. To minimize drug-induced adverse effects, the combined use of anticancer drugs with natural-derived compounds possessing antioxidant properties has become an interesting treatment strategy. Barakol is a major compound found in Cassia siamea, an edible plant with antioxidant and anticancer properties. Therefore, barakol could potentially be used in combination with doxorubicin to synergize the anticancer effect, while minimizing the oxidative-related toxicities. Herein, the potential of barakol (0.0043-43.0 µM) to synergize the anticancer effect of low-dose doxorubicin (0.5 and 1.0 µM) was investigated. Results indicated that barakol could enhance the cytotoxic effect of low-dose doxorubicin by affecting the cell viability of the treated cells. Furthermore, the co-treatment with barakol and low-dose doxorubicin decreased the levels of intracellular ROS when compared with the control. Moreover, the antimetastatic effect of the barakol itself was studied through its ability to inhibit metalloproteinase-3 (MMP-3) activity and prevent cell migration. Results revealed that the barakol inhibited MMP-3 activity and prevented cell migration in time- and dose-dependent manners. Additionally, barakol was a non-cytotoxic agent against the normal tested cell line (MRC-5), which suggested its selectivity and safety. Taken together, barakol could be a promising compound to be further developed for combination treatment with low-dose doxorubicin to improve therapeutic effectiveness but decrease drug-induced toxicities. The inhibitory effects of barakol on MMP-3 activity and cancer cell migration also supported its potential to be developed as an antimetastatic agent.

3,4-Dihydroxybenzalacetone Inhibits the Propagation of Hydrogen Peroxide-Induced Oxidative Effect via Secretory Components from SH-SY5Y Cells.

The polyphenol derivative 3,4-dihydroxybenzalacetone (DBL) is the primary antioxidative component of the medicinal folk mushroom Chaga (Inonotus obliquus (persoon) Pilat). In this study, we investigated whether the antioxidative effect of DBL could propagate to recipient cells via secreted components, including extracellular vesicles (EVs), after pre-exposing SH-SY5Y human neuroblastoma cells to DBL. First, we prepared EV-enriched fractions via sucrose density gradient ultracentrifugation using conditioned medium from SH-SY5Y cells exposed to 100 µM hydrogen peroxide (H2O2) for 24 h, with and without 1 h of 5 µM DBL pre-treatment. CD63 immuno-dot blot analysis demonstrated that fractions with density of 1.06-1.09 g/cm3 had CD63-like immuno-reactivities. Furthermore, the 2,2-diphenyl-1-picrylhydrazyl assay revealed that the radical scavenging activity of fraction 11 (density of 1.06 g/cm3), prepared after 24-h H2O2 treatment, was significantly increased compared to that in the control group (no H2O2 treatment). Notably, 1 h of 5 µM DBL pre-treatment or 5 min of heat treatment (100 °C) diminished this effect, although concentrating the fraction by 100 kDa ultrafiltration enhanced it. Overall, the effect was not specific to the recipient cell types. In addition, the uptake of fluorescent Paul Karl Horan-labeled EVs in concentrated fraction 11 was detected in all treatment groups, particularly in the H2O2-treated group. The results suggest that cell-to-cell communication via bioactive substances, such as EVs, in conditioned SH-SY5Y cell medium, propagates the H2O2-induced radical scavenging effect, whereas pre-conditioning with DBL inhibits it.

Effects of Munc13-1 and Munc18-1 on dopamine secretion dysfunction in manganese-exposed SH-SY5Y cells / 环境与职业医学

Background Neurotransmitter secretion disorder induced by chronic manganese poisoning has always been one of the important causes of body injury, but the mechanism of neurotransmitter secretion disorder caused by manganese is not clear at present. Objective To investigate the effects of presynaptic membrane intracellular protein 13-1 (Munc13-1) and synapse fusion protein binding protein 18-1 (Munc18-1) on dopamine secretion dysfunction induced by manganese chloride (MnCl2) in human neuroblastoma (SH-SY5Y) cells. Methods A SH-SY5Y cell model induced by MnCl2 was established. Cell viability was measured by MTT assay. Four experimental groups were set up: control group and low-, medium-, and high-dose manganese groups (0, 100, 200, and 400 μmol·L−1 MnCl2). They were treated with corresponding doses of MnCl2 for 24 h. The secretion of dopamine was measured by enzyme-linked immunosorbent assay. The mRNA expression of Syntaxin-1 was detected by real-time quantitaive PCR. Total cell proteins were extracted, and the protein expression levels of Munc13-1, Munc18-1, and Syntaxin-1 were detected by Western blotting. The correlations of MnCl2 exposure and dopamine secretion with the protein expressions of Munc13-1 and Munc18-1 were also analyzed by Pearson correlation. Results Compared with the control group, the cell viability rate decreased gradually with the increase of manganese exposure concentration, and the difference between the medium- and the high-dose manganese groups was statistically significant (P<0.05). The concentration of dopamine in cell culture medium of all manganese exposure groups decreased with the increase of manganese concentration, and compared with the control group and the low-dose manganese group, the medium- and the high-dose manganese groups were statistically significant (P<0.05). The expression of Syntaxin-1 at mRNA or protein level did not change significantly among groups (P>0.05). Compared with the control group, the protein expression of Munc13-1 decreased and that of Munc18-1 increased with the increase of manganese concentration (P<0.05). Compared with the low-dose manganese group, the changes of Munc13-1 protein in the high-dose manganese group and Munc18-1 protein in the medium- and high-dose manganese groups had statistical significance (P<0.05). Compared with the medium-dose manganese group, the protein changes of Munc18-1 in the high-dose manganese group were statistically significant (P<0.05). The correlation analysis showed that MnCl2 dose was negatively correlated with Munc13-1 protein expression (r=−0.898, P<0.05), and positively correlated with Munc18-1 protein expression (r=0.678, P<0.05). Dopamine secretion was positively correlated with Munc13-1 protein expression (r=0.932, P<0.05), and negatively correlated with Munc18-1 protein expression (r=−0.817, P<0.05). Conclusion The inhibition of dopamine secretion in SH-SY5Y cells induced by manganese exposure is related to up-regulation of Munc18-1 and down-regulation of Munc13-1 expression levels, which may be one of the reasons for nerve injury caused by manganese.

Phosphatidylcholine-Plasmalogen-Oleic Acid Has Protective Effects against Arachidonic Acid-Induced Cytotoxicity.

Plasmalogens are a group of glycerophospholipids containing a vinyl-ether bond at the sn-1 position in the glycerol backbone. Cellular membrane plasmalogens are considered to have important roles in homeostasis as endogenous antioxidants, differentiation, and intracellular signal transduction pathways including neural transmission. Therefore, reduced levels of plasmalogens have been suggested to be associated with neurodegenerative diseases such as Alzheimer's disease. Interestingly, although arachidonic acid is considered to be involved in learning and memory, it could be liberated and excessively activate neuronal activity to the excitotoxic levels seen in Alzheimer's disease patients. Here, we examined the protective effects of several kinds of plasmalogens against cellular toxicity caused by arachidonic acid in human neuroblastoma SH-SY5Y cells. As a result, only phosphatidylcholine-plasmalogen-oleic acid (PC-PLS-18) showed protective effects against arachidonic acid-induced cytotoxicity based on the results of lactate dehydrogenase release and ATP depletion assays, as well as cellular morphological changes in SH-SY5Y cells. These results indicate that PC-PLS-18 protects against arachidonic acid-induced cytotoxicity, possibly via improving the stability of the cellular membrane in SH-SY5Y cells.

Indoles and 1-(3-(benzyloxy)benzyl)piperazines: Reversible and selective monoamine oxidase B inhibitors identified by screening an in-house compound library.

The therapeutic indications for monoamine oxidases A and B (MAO-A and MAO-B) inhibitors that have emerged from biological studies on animal and cellular models of neurological and oncological diseases have focused drug discovery projects upon identifying reversible MAO inhibitors. Screening of our in-house academic compound library identified two hit compounds that inhibit MAO-B with IC50 values in micromolar range. Two series of indole (23 analogues) and 3-(benzyloxy)benzyl)piperazine (16 analogues) MAO-B inhibitors were derived from hits, and screened for their structure-activity relationships. Both series yielded low micromolar selective inhibitors of human MAO-B, namely indole 2 (IC50 = 12.63 ± 1.21 µM) and piperazine 39 (IC50 = 19.25 ± 4.89 µM), which is comparable to selective MAO-B inhibitor isatin (IC50 = 6.10 ± 2.81 µM), yet less potent in comparison to safinamide (IC50 = 0.029 ± 0.002 µM). Selective MAO-B inhibitors 2, 14, 38 and 39 exhibited favourable permeation of the blood-brain barrier and low cytotoxicity in the human neuroblastoma cell line SH-SY5Y.

Protective role of selenium on MPP+ and homocysteine-induced TRPM2 channel activation in SH-SY5Y cells.

Homocysteine is an intermediate product of biochemical reactions occurring in living organisms. It is known that drugs that increase dopamine synthesis used in Parkinson's disease (PD) cause an increase in the plasma homocysteine level. As the plasma homocysteine level increases, the amount of intracellular free calcium ion ([Ca2+]i) and oxidative stress increase. As a result, it contributes to the excitotoxic effect by causing neurodegeneration. TRPM2 cation channel is activated by high [Ca2+]i and oxidative stress. The role of TRPM2 in the development of neuronal damage due to the increase in homocysteine in PD has not yet been elucidated. In current study, we aimed to investigate the role of the TRPM2 and selenium (Se) in SH-SY5Y neuronal cells treated with homocysteine (HCT) and MPP . SH-SY5Y cells were divided into four groups: control, MPP, MPP + HCT, and MPP + HCT + Se. The results of plate reader assay, confocal microscope imaging, and western blot analyses indicated upregulation of apoptosis, [Ca2+]i, mitochondrial membrane depolarization, caspase activation, and intracellular ROS values in the cells. The MPP + HCT group had considerably higher values than the other groups. The MPP + HCT + Se group had significantly lower values than all the other groups except the control group. In addition, incubation of MPP + HCT and MPP + HCT + Se groups with TRPM2 antagonist 2-APB increased cell viability and reduced intracellular calcium influx and apoptosis levels. It is concluded that the activation of TRPM2 was propagated in HCT and MPP-induced SH-SY5Y cells by the increase of oxidative stress. The antioxidant property of Se regulated the TRPM2 channel activation and neurodegeneration by providing intracellular oxidant/antioxidant balance.

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

BACKGROUND: 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. METHODS AND RESULTS: To establish Parkinson's Disease (PD) model in cell culture conditions, SH-SY5Y cells were exposed to 200 µM 6-OHDA for 1 day. Prior to 6-OHDA treatment, SH-SY5Y cells had been pre-treated with bromelain (25 µg/mL, 50 µg/mL, 75 µg/mL and 100 µg/mL). After 1 day, 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. CONCLUSIONS: These findings indicated that bromelain, with its neuroprotective features can be useful for neuroprotection in PD.

[Mechanism of puerarin reversing SH-SY5Y cell injury induced by Aß_(1-42) based on proteomics].

Puerarin has the anti-Alzheimer's disease (AD) activity,which can reverse nerve injury induced by Aßand inhibit neuronal apoptosis.However,its potential pharmacodynamic mechanism still needs to be further researched.The occurrence and development of AD is due to the change of multiple metabolic links in the body,which leads to the destruction of balance.Puerarin may act on multiple targets and multiple metabolic processes to achieve therapeutic purposes.Quantitative proteomic analysis provides a new choice to understand the mechanism as completely as possible.This research adopted SH-SY5Y cells induced by Aß_(1-42)to establish AD cell model,and Aßimmunofluorescence detection showed that Aßdecreased significantly after puerarin intervention.The mechanism of puerarin reversing SH-SY5Y cell injured by Aß_(1-42)was further explored by using label-free non-labeled quantitative technology and Western blot detection based on bioinformatics analysis result.The results showed that most of the differential proteins were related to biological processes such as cellular component organization or biogenesis,cellular component organization and cellular component biogenesis,and they mainly participated in the top ten pathways of P value such as pathogenic Escherichia coli infection,m TOR signaling pathway,regulation of autophagy,regulation of actin cytoskeleton,spliceosome,hepatocellular carcinoma,tight junction,non-small cell lung cancer,apoptosis and gap junction.Annexin V/PI flow cytometry and TUNEL were used to detect apoptosis,and the results showed that Aßdecreased significantly and the rate of apoptosis decreased significantly after puerarin intervention.Western blot analysis found that the protein expression level of autophagy related protein LC3Ⅱwas up-regulated after Aßinduction,and the degree of this up-regulation was further enhanced in puerarin intervention group.The trend of the ratio of LC3Ⅱ/LC3Ⅰamong groups was the same as the protein expression level of LC3Ⅱ，the protein expression level of p62 in the control group,AD model group and puerarin intervention group decreased successively.Protein interaction network analysis showed that CAP1 was correlated with TUBA1B,HSP90AB2P,DNM1L,TUBA1A and ERK1/2,and the correlation between CAP1 and ERK1/2 was the highest among them.Western blot showed that the expressions of p-ERK1/2,Bax and CAP1 were significantly down-regulated and the protein expression level of Bcl-2 was significantly up-regulated after puerarin intervention.Therefore,puerarin might improve the SH-SY5Y cells injured by Aß_(1-42)through the interaction of multiple biological processes and pathways in cells multiple locations,and CAP1 might play an important role among them.

In vitro differentiation modifies the neurotoxic response of SH-SY5Y cells.

The SH-SY5Y cell line is commonly used for the assessment of neurotoxicity in drug discovery. These neuroblastoma-derived cells can be differentiated into neurons using many methods. The present study has compared 24 of these differentiation methods on SH-SY5Y cells. After morphologic selection of the three most differentiating media (retinoic acid in 10% fetal bovine serum (FBS), staurosporine in 1% FBS medium, and cyclic adenosine monophosphate (cAMP) in B21-supplemented neurobasal medium), cells were analyzed for pan-neuronal and specific neuronal protein expression by fluorescent automated imaging. The response of SH-SY5Y to a set of compounds of known toxicity was examined in these culture conditions performed in 2D, and also in a 3D hyaluronic acid-based hydroscaffold™ which mimics the extracellular matrix. The extent of neuronal markers expression and the sensitivity to neurotoxic compounds varied according to the differentiation medium. The cAMP B21-supplemented neurobasal medium led to the higher neuronal differentiation, and the higher sensitivity to neurotoxic compounds. The culture in 3D modified the neurotoxic response, through a lower sensitivity of cells compared to the 2D culture. The in vitro differentiation environment influences the neurotoxic response of SH-SY5Y cells and thus should be considered carefully in research as well as in drug discovery.

Synthesis of Novel Baicalein Amino Acid Derivatives and Biological Evaluation as Neuroprotective Agents.

Baicalein, a famously effective component of the traditional Chinese medicine Rhizoma Huang Qin (Scutellaria altissima L.), has been proved to have potent neuroprotection and anti-platelet aggregation effects with few side effects. Meanwhile, recent studies have revealed that the introduction of amino acid to baicalein could improve its neuroprotective activity. In the present study, a series of novel baicalein amino acid derivatives were designed, synthesized, and screened for their neuroprotective effect against tert-butyl, hydroperoxide-induced, SH-SY5Y neurotoxicity cells and toxicity on the normal H9C2 cell line by standard methylthiazol tetrazolium (MTT) assay. In addition, all of the newly synthesized compounds were characterized by 1H-NMR, 13C-NMR, and high resolution mass spectrometry (HR-MS). The results showed that most of the compounds provided more potent neuroprotection than baicalein, and were equivalent to the positive drug edaravin. They showed no obvious cytotoxicity on normal H9C2 cells. Notably, the most active compound 8 displayed the highest protective effect (50% effective concentration (EC50) = 4.31 µM) against tert-butyl, hydroperoxide-induced, SH-SY5Y neurotoxicity cells, which was much better than the baicalein (EC50 = 24.77 µM) and edaravin (EC50 = 5.62 µM). Further research on the chick chorioallantoic membrane (CAM) model indicated that compound 8 could significantly increase angiogenesis, which might promote neurovascular proliferation. The detection of apoptosis analysis showed that compound 8 could dramatically alleviate morphological manifestations of cell damage. Moreover, the benzyloxycarbonyl (cbz)-protected baicalein amino acid derivatives showed better neuroprotective activity than the t-Butyloxy carbonyl (boc)-protected derivatives.

Neuroprotective effect of Mayan medicinal plant extracts against glutamate-induced toxicity.

Neurological disorders are a public health problem worldwide for which there is currently no direct treatment of the cause of the disorder. The goal of this study was to investigate the potential in vitro neuroprotective property of plants used in Mayan traditional medicine. Plant ethanolic extracts were prepared and tested on models in which neuronal damage was induced by glutamate, i.e., a human neuroblastoma cell line (SH-SY5Y) and rat cortical neurons. HPLC profiles from active extracts were also obtained. A total of 51 plant species were identified in the literature as plant species used in Mayan traditional medicine for the treatment of symptoms suggestive of neurological disorders, and we studied 34 of these in our analysis. Six extracts had a neuroprotective effect on SH-SY5Y cells, with the most active extract being that from Schwenckia americana roots (half maximal effective concentration [EC50] 11.3 ± 2.9 µg/mL), and three extracts exhibited a neuroprotective effect in the rat neuron cortical model, with the most active extract being that from Elytraria imbricata aerial parts (EC50 6.8 ± 3.1 µg/mL). These results suggest that the active extracts from such plants have the potential to be a great resource. Future studies should be performed that are more extensive and which isolate the active constituents.

The protective effects of vernicilignan A, a new flavonolignan isolated from Toxicodendron vernicifluum on SH-SY5Y cells against oxidative stress-induced injury.

In this study, a new flavonolignan vernicilignan A was isolated from Toxicodendron vernicifluum. The neuroprotective effects of this compound against H2O2 induced cell injury in SH-SY5Y cells were evaluated by MTT assay and LDH release assay. Vernicilignan A dose-dependently attenuated the cell injury and LDH release induced by H2O2 in SH-SY5Y cells. Further study indicated that vernicilignan A reduced cell apoptosis caused by H2O2 treatment via regulation of some apoptotic related proteins including Bax, Bcl-2, caspase 3 and caspase 9. Also, vernicilignan A increase the cell viability of H2O2 treated cells via the activation of Akt and GSK3ß. Base on the findings, vernicilignan A exhibited neuroprotective effects through the activation of PI3K/Akt signaling and inhibition of mitochondria apoptosis pathway. Vernicilignan A might be a promising therapeutic agent for oxidative stress induced neurodegenerative diseases.

[Effect of Ginkgo biloba extract (EGb50) on mitochondrial function in SH-SY5Y cells after hypoxia/reoxygenation injury].

Ischemic cerebrovascular disease and cerebral ischemia/reperfusion injury threaten the health of human being. We studied the protective effect of Ginkgo biloba extract 50 (EGb50) on the mitochondrial function in SH-SY5Y cells after hypoxia/reoxygenation (H/R) injury and explored its mechanisms, so as to provide new ideas for studies on the treatment for ischemic cerebrovascular disease. We established the H/R injury model in SH-SY5Y cells after administrating EGb50. Subsequently, the mitochondrial membrane potential and the concentration of intracellular Ca²âº were measured by flow cytometer. The levels of optic atrophy1 (Opa1) and dynamin-like protein 1 (Drp1) were evaluated by immunofluorescence and western blot. The results showed that the mitochondrial membrane potential was decreased and the level of intracellular Ca²âº was increased after H/R injury. Moreover, the expression of mitochondrial fusion protein Opa1 was decreased, while the expression of mitochondrial fission protein Drp1 was increased. However, EGb50 significantly increased the mitochondrial membrane potential and suppressed the level of intracellular Ca²âº. In addition, EGb50 increased the expression of Opa1 and decreased the expression of Drp1. The results demonstrated that EGb50 has a neuroprotective effect on SH-SY5Y cells after H/R injury, and could improve the energy metabolism and mitochondrial function. The underlying mechanisms may be associated with the regulation of mitochondrial fusion and fission, which provided data support for the treatment of ischemic cerebrovascular disease with EGb50.

Effect of Ginkgo biloba extract (EGb50) on mitochondrial function in SH-SY5Y cells after hypoxia/reoxygenation injury / 中国中药杂志

Ischemic cerebrovascular disease and cerebral ischemia/reperfusion injury threaten the health of human being. We studied the protective effect of Ginkgo biloba extract 50 (EGb50) on the mitochondrial function in SH-SY5Y cells after hypoxia/reoxygenation (H/R) injury and explored its mechanisms, so as to provide new ideas for studies on the treatment for ischemic cerebrovascular disease. We established the H/R injury model in SH-SY5Y cells after administrating EGb50. Subsequently, the mitochondrial membrane potential and the concentration of intracellular Ca²⁺ were measured by flow cytometer. The levels of optic atrophy1 (Opa1) and dynamin-like protein 1 (Drp1) were evaluated by immunofluorescence and western blot. The results showed that the mitochondrial membrane potential was decreased and the level of intracellular Ca²⁺ was increased after H/R injury. Moreover, the expression of mitochondrial fusion protein Opa1 was decreased, while the expression of mitochondrial fission protein Drp1 was increased. However, EGb50 significantly increased the mitochondrial membrane potential and suppressed the level of intracellular Ca²⁺. In addition, EGb50 increased the expression of Opa1 and decreased the expression of Drp1. The results demonstrated that EGb50 has a neuroprotective effect on SH-SY5Y cells after H/R injury, and could improve the energy metabolism and mitochondrial function. The underlying mechanisms may be associated with the regulation of mitochondrial fusion and fission, which provided data support for the treatment of ischemic cerebrovascular disease with EGb50.

White sesame seed water-soluble fraction enhances human neuroblast cell viability via an anti-apoptotic mechanism.

Defatted sesame seed flour is recovered as a byproduct after oil extraction and is usually considered a waste product. Previously, we showed that water-soluble fractions purified from defatted white and gold sesame seed flour exhibited good antioxidant activity in vitro. We also identified ferulic acid and vanillic acid as the bioactive antioxidants in both white and gold sesame seed water-soluble fractions (WS-wsf and GS-wsf, respectively). In this study, we hypothesized that WS-wsf and GS-wsf may have neuroprotective effects due to their antioxidant potential. Treatment with WS-wsf for 24 hours enhanced human neuroblastoma SH-SY5Y cell viability and proliferation, while GS-wsf, ferulic acid, and vanillic acid did not show similar effects. In addition, WS-wsf (1-3 mg/mL) significantly and dose-dependently protected SH-SY5Y cells against camptothecin-induced apoptosis, suggesting the involvement of an anti-apoptosis mechanism in the neuroprotective effects of WS-wsf. In fact, treatment with WS-wsf significantly decreased the mRNA expression levels of pro-apoptotic Bax and p53 genes. WS-wsf also enhanced Bcl-2 protein level and Akt phosphorylation. Taken together, this study showed that WS-wsf has interesting neuroprotective potential via an anti-apoptotic mechanism, which is independent from its antioxidant capacity.

Component analysis and target cell-based neuroactivity screening of Panax ginseng by ultra-performance liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry.

Ginseng is one of the most widely used natural medicines in the world. Recent studies have suggested Panax ginseng has a wide range of beneficial effects on aging, central nervous system disorders, and neurodegenerative diseases. However, knowledge about the specific bioactive components of ginseng is still limited. This work aimed to screen for the bioactive components in Panax ginseng that act against neurodegenerative diseases, using the target cell-based bioactivity screening method. Firstly, component analysis of Panax ginseng extracts was performed by UPLC-QTOF-MS, and a total of 54 compounds in white ginseng were characterized and identified according to the retention behaviors, accurate MW, MS characteristics, parent nucleus, aglycones, side chains, and literature data. Then target cell-based bioactivity screening method was developed to predict the candidate compounds in ginseng with SH-SY5Y cells. Four ginsenosides, Rg2, Rh1, Ro, and Rd, were observed to be active. The target cell-based bioactivity screening method coupled with UPLC-QTOF-MS technique has suitable sensitivity and it can be used as a screening tool for low content bioactive constituents in natural products.

Chemical constituents of Narcissus tazetta var. chinensis and their antioxidant activities.

Two new flavan derivatives tazettones C-D (1-2), one new ß-coumaranone (tazettone E, 3), one new flavan (tazettone F, 4), and one new phenylpropanoid (tazettone G, 5), together with six known flavonoids (6-11), were isolated from the bulbs of Narcissus tazetta var. chinensis Roem. Their structures were elucidated by spectroscopic analysis. In addition, the structures of 1-3 were confirmed by single crystal X-ray diffraction. All isolated compounds were tested for antioxidant activity by Cell Counting Kit-8 (CCK-8) assay. Compounds 6-8 and 10-11 exhibited potent antioxidant activity against H2O2-induced impairment in human SH-SY5Y neuroblastoma cells at tested concentrations.

Nimodipine, an L-type calcium channel blocker attenuates mitochondrial dysfunctions to protect against 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-induced Parkinsonism in mice.

Parkinson's disease (PD), the most common progressive neurodegenerative movement disorder, results from loss of dopaminergic neurons of substantia nigra pars compacta. These neurons exhibit Cav1.3 channel-dependent pacemaking activity. Epidemiological studies suggest reduced risk for PD in population under long-term antihypertensive therapy with L-type calcium channel antagonists. These prompted us to investigate nimodipine, an L-type calcium channel blocker for neuroprotective effect in cellular and animal models of PD. Nimodipine (0.1-10 µM) significantly attenuated 1-methyl-4-phenyl pyridinium ion-induced loss in mitochondrial morphology, mitochondrial membrane potential and increases in intracellular calcium levels in SH-SY5Y neuroblastoma cell line as measured respectively employing Mitotracker green staining, TMRM, and Fura-2 fluorescence, but only a feeble neuroprotective effect was observed in MTT assay. Nimodipine dose-dependently reduced 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonian syndromes (akinesia and catalepsy) and loss in swimming ability in Balb/c mice. It attenuated MPTP-induced loss of dopaminergic tyrosine hydroxylase positive neurons in substantia nigra, improved mitochondrial oxygen consumption and inhibited reactive oxygen species production in the striatal mitochondria measured using dichlorodihydrofluorescein fluorescence, but failed to block striatal dopamine depletion. These results point to an involvement of L-type calcium channels in MPTP-induced dopaminergic neuronal death in experimental parkinsonism and more importantly provide evidences for nimodipine to improve mitochondrial integrity and function.

Protection of 20 Chinese materia medica extracts to Aβ25-35-induced SH-SY5Y cell injury using high content screening / 中草药

Objective: To identify neuroprotective extracts with the protective effects on Aβ25-35-induced SH-SY5Y cell injury via high content screening (HCS). Methods: Hoechst 33342/PI double staining method was used to screen neuroprotective extracts from 60 Chinese materia medica (CMM) extracts. Further more, the effects of neuroprotective extracts on Aβ25-35-induced changes in the levels of Caspase-3/7 were detected. Results: The results showed that 17 extracts had obviously neuroprotective effects. Among the 17 extracts, 8 of them inhibited Aβ25-35-induced up-regulation of Caspase-3/7. Conclusion: HCS is an efficient method to screen neuroprotective extracts with the protective effects of Aβ25-35-induced SH-SY5Y cell injury. The neuroprotective extracts have potential medicinal value in Alzheimer's disease.

Tetramethylpyrazine induces SH-SY5Y cell differentiation toward the neuronal phenotype through activation of the PI3K/Akt/Sp1/TopoIIß pathway.

Tetramethylpyrazine (TMP) is an active compound extracted from the traditional Chinese medicinal herb Chuanxiong. Previously, we have shown that TMP induces human SH-SY5Y neuroblastoma cell differentiation toward the neuronal phenotype by targeting topoisomeraseIIß (TopoIIß), a protein implicated in neural development. In the present study, we aimed to elucidate whether the transcriptional factors specificity protein 1 (Sp1) and nuclear factor Y (NF-Y), in addition to the upstream signaling pathways ERK1/2 and PI3K/Akt, are involved in modulating TopoIIß expression in the neuronal differentiation process. We demonstrated that SH-SY5Y cells treated with TMP (80µM) terminally differentiated into neurons, characterized by increased neuronal markers, tubulin ßIII and microtubule associated protein 2 (MAP2), and increased neurite outgrowth, with no negative effect on cell survival. TMP also increased the expression of TopoIIß, which was accompanied by increased expression of Sp1 in the differentiated neuron-like cells, whereas NF-Y protein levels remained unchanged following the differentiation progression. We also found that the phosphorylation level of Akt, but not ERK1/2, was significantly increased as a result of TMP stimulation. Furthermore, as established by chromatin immunoprecipitation (ChIP) assay, activation of the PI3K/Akt pathway increased Sp1 binding to the promoter of the TopoIIß gene. Blockage of PI3K/Akt was shown to lead to subsequent inhibition of TopoIIß expression and neuronal differentiation. Collectively, the results indicate that the PI3K/Akt/Sp1/TopoIIß signaling pathway is necessary for TMP-induced neuronal differentiation. Our findings offer mechanistic insights into understanding the upstream regulation of TopoIIß in neuronal differentiation, and suggest potential applications of TMP both in neuroscience research and clinical practice to treat relevant diseases of the nervous system.