The immunogenic involvement of miRNA-492 in mycoplasma pneumoniae infection in pediatric patients

Abstract Objective: This study aimed to evaluate the role of miRNA-492 in the progression of mycoplasma pneumoniae (MP) infection in pediatric patients. Methods: Forty-six children admitted to the present study's hospital and diagnosed with mycoplasma pneumonia were recruited as the study group from March 2018 to August 2019, and 40 healthy children were selected as the control group. Results: The expression levels of miRNA-492, TNF-α, IL-6 and IL-18 in the study group were significantly higher than those in the control group (p < 0.05). There was no significant correlation between miRNA-492 and most of the immune-correlated indicators in the study group, except for IL-6, IL-18 and HMGB1. Meanwhile, overexpression of miRNA-492 increased IL-6 secretion in PMA-activated monocytes (p < 0.01). Conclusion: The present study's results suggested that miRNA-492 might play a role in the pathogenesis of mycoplasma pneumoniae pneumonia in children by regulating the secretion of immune-inflammatory factors such as IL-6 and IL-18 in the mononuclear macrophages.

Effects of Ligusticum Chuanxiong extract on MPP+-induced SH-SY5Y cells in Parkinson’s syndrome model via miR-23a-3p/SNCA axis / 西安交通大学学报(医学版)

【Objective】 To explore the effects of Ligusticum Chuanxiong extract on MPP+-induced SH-SY5Y cell damage and Parkinson’s syndrome. 【Methods】 1-methyl-4phenylpyridine ion (MPP+) interfered with SH-SY5Y to establish a cell model of elderly Parkinson’s syndrome (SH-SY5Y-MPP+). After intervention with Ligusticum Chuanxiong extract, cell proliferation and apoptosis as well as miR-23a-3p and SNCA expressions were detected. In addition, the changes of SH-SY5Y-MPP+ after regulating the expression of miR-23a-3p and SNCA were observed, and the relationship between miR-23a-3p and SNCA was verified by dual luciferase reporter. 【Results】 The cell proliferation capacity of SH-SY5y-MPP+ was significantly lower than that of SH-SY5Y, while the apoptosis rate was higher than that of SH-SY5Y (P<0.05). Under the intervention of Ligusticum Chuanxiong extract, the proliferation ability of SH-SY5Y-MPP+, and Bcl-2 and SNCA protein increased, the apoptosis rate, miR-23a-3p, and Bax proteins decreased (P<0.05). Both silencing miR-23a-3p and increasing SNCA could promote the proliferation of SH-SY5Y-MPP+ and inhibit apoptosis, while increasing miR-23a-3p and silencing SNCA were the opposite (P<0.05). The online target gene prediction website found that miR-23a-3p and SNCA had complementary sites that could bind, and the dual luciferase reporter enzyme showed that the firefly activity of SNCA-wt was significantly inhibited after the miR-23a-3p mimic sequence was transfected (P<0.05). After increasing miR-23a-3p, the expression of SNCA protein in SH-SY5Y-MPP+ decreased, while silencing miR-23a-3p was the opposite (P<0.05). Rescue experiments showed that the intervention effect of Ligusticum Chuanxiong extract on SH-SY5Y-MPP+ was completely reversed by increasing miR-23a-3p or silent SNCA (P>0.05); the effect of increasing miR-23a-3p on SH-SY5Y-MPP+ increased SNCA reversion (P>0.05). 【Conclusion】 Ligusticum Chuanxiong extract can affect the biological behavior changes of SH-SY5Y induced by MPP+ by regulating the miR-23a-3p/SNCA axis, which may be a new direction for the treatment of elderly Parkinson’s syndrome in the future.

The critical function of miR-1323/Il6 axis in children with Mycoplasma pneumoniae pneumonia

Abstract Objective: Mycoplasma pneumoniae pneumonia (MPP) is a common respiratory infection in children. Tumor necrosis factor-cx (TNF-α), interleukin-17 (IL-17), and IL-6 have correlation with Mycoplasma pneumoniae lung infection and MPP pathogenesis. Method: miRNAs participate in the pathogenesis of various diseases by regulating the development and differentiation of the immune cell. Blood was collected and total RNA was isolated. miRNA microarrays were performed to identify differentially expressed miRNAs in MPP patients. The levels of relative miRNAs and mRNAs were evaluated by qRT-PCR. Results: There are 23 differentially expressed miRNAs in MPP children's plasma, 15 miRNAs had enhanced expression and 8 had depressed expression. MPP patients showed lower mir-1323 level in blood samples than healthy controls. MPP patients with pleural effusion had much higher Il6 and Il17a mRNA levels than those without pleural effusion. The expression level of Il6 had a negative correlation with miR-1323 level. In the human THP-1 cell line, the level of miR-1323 was significantly reduced through lipopolysaccharides treatment. In THP-1 cells, overexpression or silencing of miR-1323 significantly reduced or promoted Il6 expression. Conclusion: In conclusion, miR-1323 targets the mRNA of Il6 and inhibits the expression of Il6. The pathogenesis of MPP inhibits the expression of miR-1323 in macrophages, triggers the overexpression of Il6, and enhances inflammation response.

SNHG1 promotes MPP+-induced cytotoxicity by regulating PTEN/AKT/mTOR signaling pathway in SH-SY5Y cells via sponging miR-153-3p

BACKGROUND: Long non-coding RNA small molecule RNA host gene 1 (SNHG1) was previously identified to be relevant with Parkinson's disease (PD) pathogenesis. This work aims to further elucidate the regulatory networks of SNHG1 involved in PD. Methods: 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine-hydrochloride (MPTP)-induced mice and 1-methyl-4-phenylpyridinium (MPP+)-treated SH-SY5Y cells were respectively constructed as the in vivo and in vitro PD models. Expression levels of SNHG1 and miR-153-3p were detected by qRT-PCR. Protein expression levels of phosphate and tension homology deleted on chromosome ten (PTEN) were measured by western blotting assay. Cell viability and apoptosis were determined by MTT and flow cytometry assays. The interactions among SNHG1, miR-153-3p and PTEN were identified by luciferase reporter assay, RNA immunoprecipitation, and/or RNA pull-down analysis. RESULTS: Increased SNHG1 expression was found in midbrain of MPTP-induced PD mice and MPP+-treated SH-SY5Y cells. Overexpression of SNHG1 lowered viability and enhanced apoptosis in MPP+-treated SH-SY5Y cells. Moreover, SNHG1 acted as a molecular sponge to inhibit the expression of miR-153-3p. Furthermore, miR-153-3p-mediated suppression of MPP+-induced cytotoxicity was abated following SNHG1 up-regulation. Additionally, PTEN was identified as a direct target of miR-153-3p, and SNHG1 could serve as a competing endogenous RNA (ceRNA) of miR-153-3p to improve the expression of PTEN. Besides, enforced expression of PTEN displayed the similar functions as SNHG1 overexpression in regulating the viability and apoptosis of MPP+-treated SH-SY5Y cells. Finally, SNHG1 was found to activate PTEN/AKT/mTOR signaling pathway in SH-SY5Y cells by targeting miR-153-3p. CONCLUSION: SNHG1 aggravates MPP+-induced cellular toxicity in SH-SY5Y cells by regulating PTEN/AKT/mTOR signaling via sponging miR-153-3p, indicating the potential of SNHG1 as a promising therapeutic target for PD.

Clinical Efficacy of Different Doses of Methylprednisolone Combined with Azithromycin in the Treatment of Severe Pulmonary Lobar Degeneration in Children with MP / 中国药学杂志

OBJECTIVE: To discuss the effect of different doses of methylprednisolone combined with azithromycin in the treatment of severe pulmonary lobar degeneration in children with MPP. METHODS: One hundred and twenty-eight children with severe MPP of pulmonary lobar degeneration were randomly divided into the low dose group and the high dose group with 64 cases in each group. The children of two groups were given azithromycin. On this basis, the children of low dose group were given conventional doses of methylprednisolone, the children of high dose group were given high-dose methylprednisolone. The clinical efficacy, immune function, inflammatory indexes and adverse reaction were compared.RESULTS: Compared with the low dose group, the disappearance time of cough, expectoration, wheezing and fever in the observation group was significantly shorter, the effective rate of the high dose group was significantly higher,the incidence of respiratory sequelae was significantly higher, the IL-2, IL-6, IL-13, TNF-α, IFN-γ in the observation group were significantly better (P0.05). CONCLUSION: Large dose of methylprednisolone combined with azithromycin can relieve the clinical symptoms of severe MPP in children with lobar degeneration. It also can promote the rehabilitation of the disease, effectively inhibit the inflammatory response of children and long-term sequelae, has the exact application value.

Effects of salvianolic acid D on mitochondrial function and biosynthesis in SH-SY5Y cells after MPP+injury / 中国药理学通报

Aim To investigate the effects of salvianol-ic acid D ( SalD) on mitochondrial function and bio- synthesis in SH-SY5Y cells after MPP+injury and the possible mechanisms. Methods The cell model was established by MPP+injury in SH-SY5Y cells. The cytotoxicity of MPP+was detected by MTT assay. The effects of SalD on viability of SH-SY5Y cells were ex-amined by MTT and LDH assay. The apoptosis of SH-SY5Y cells was detected by AO/EB assay. The levels of ROS and mitochondrial superoxide were determined using DCFH-DA and MitoSOX probes, respectively. Mitochondrial function was examined by measuring ATP level and mitochondrial membrane potential. The levels of PGC-1α and its downstream regulatory genes NRF1 and TFAM mRNA were detected by qPCR. The protein levels of PGC-1α, NRF1 and TFAM in cells were detected by Western blot and immunofluorescence assays. Results MPP+injury resulted in a significant reduction of cell viability to 51.34%. 0.1, 1, 5 μmol ·L-1SalD and 5 mmol·L-1NAC could reduce MPP+-induced SH-SY5Y cell injury and LDH release. The cell viability increased to 67.98% , 71.79% , 76.91% and 77.55% , respectively. Moreover, SalD could reduce the increase of intracellular ROS and mi-tochondrial superoxide induced by MPP+, decrease mitochondrial membrane potential and improve mito-chondrial function. SalD also significantly increased both the transcription and expression levels of PGC-1α, NRF1 and TFAM. Conclusion SalD could in-hibit MPP+-induced SH-SY5Y cell injury and improve mitochondrial function and mitochondrial biosynthesis.

Acute Restraint Stress Augments 1-Methyl-4-phenyl-1,2,3,6-tetrahydropyridine Neurotoxicity via Increased Toxin Uptake into the Brain in C57BL/6 Mice / 神经科学通报·英文版

As an environmental risk factor, psychological stress may trigger the onset or accelerate the progression of Parkinson's disease (PD). Here, we evaluated the effects of acute restraint stress on striatal dopaminergic terminals and the brain metabolism of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which has been widely used for creating a mouse model of PD. Exposure to 2 h of restraint stress immediately after injection of a low dose of MPTP caused a severe loss of striatal dopaminergic terminals as indicated by decreases in the dopamine transporter protein and dopamine levels compared with MPTP administration alone. Both striatal 1-methyl-4-phenylpyridinium ion (MPP) and MPTP concentrations were significantly increased by the application of restraint stress. Striatal monoamine oxidase-B, which catalyzes the oxidation of MPTP to MPP, was not changed by the restraint stress. Our results indicate that the enhanced striatal dopaminergic terminal loss in the stressed mice is associated with an increase in the transport of neurotoxin into the brain.

Oxidative stress and autophagy in SK-N-SH cells induced by manganese chloride or 1-methyl-4-phenylpyridinium: a comparative analysis / 中华劳动卫生职业病杂志

Objective@#To investigate the effect of manganese chloride (MnCl2) or 1-methyl-4-phenylpyridinium (MPP +) on oxidative stress and autophagy in human neuroblastomaSK-N-SH cells and the mechanism of the neurotoxicity of manganese.@*Methods@#SK-N-SH cells were treated with MnCl2 or MPP+ at doses of 0.062 5, 0.125, 0.25, 0.5, 1.0, and 2.0 mmol/L for 24 hours, and MTT assay was used to measure cell viability. The cells weretreated with MnCl2 or MPP+ at doses of 0.125, 0.25, and 0.5 mmol/L for 24 hours, and flow cytometry was used to measure the content of reactive oxygen species (ROS) in cells, a laser scanning confocal microscope was used to observe autophagosome in cells, and Western blot was used to measure the expression of autophagy-related proteins P62 and LC3-II/LC3-I.@*Results@#Compared with the control group, the 0.0625-2.0 mmol/L MnCl2 and 0.125-2.0 mmol/L MPP + treatment groups had significant reductions in the viability of SK-N-SH cells, and the 0.25-2.0 mmol/L MnCl2 treatment groups had significantly lower viability than the groups treated with the same doses of MPP+ (all P<0.05) . Compared with the control group, the 0.125-0.25 mmol/L MnCl2 and 0.125-0.5 mmol/L MPP+ treatment groups had significant increases in the content of ROS, and the 0.25-0.5 mmol/L MPP+ treatment groups had significantly higher content of ROS than the groups treated with the same doses of MnCl2 (all P<0.05) . Compared with the control group, the 0.25-0.5 mmol/L MnCl2 andMPP+ treatment groups had significant increases in autophagy-related proteins LC3-II/LC3-I and significant reductions in P62 expression; the 0.125-0.5 mmol/L MPP+ treatment groups had significantly higher LC3-II/LC3-I than the groups treated with the same doses of MnCl2, and the 0.125 and 0.25 mmol/L MPP + treatment groups had significantly lower P62 expression than the groups treated with the same doses of MnCl2 (all P<0.05) .@*Conclusion@#Both MnCl2 and MPP+ can induce oxidative stress and autophagy in SK-N-SH cells, and MPP+ has a significantly greater inductive effect on autophagy of SK-N-SH cells than MnCl2.

The Reliability and Validity Evaluation of Mandarin Version of the Parental Perspective Instrument for Pediatric Cochlear Implantation / 听力学及言语疾病杂志

Objective The aim of the present study is to evaluate the reliability and validity of the Mandarin version of the PP (MPP) .Methods The first step in the establishment was to translate the original English version into mandarin version with the method of cross -culture translation .The reliability was performed with the internal consistency analysis and test -retest reliability .The validity was performed for the content validity and structure va-lidity .The samples were from 80 Chinese CI children ,and 43 parents answered this questionnaire again 1 month lat-er to evaluate the test -retest reliability .The average age at cochlear implantation were 26 ± 14 months ,ranging from 7 months to 68 months ,the average duration of CI use were 10 ± 7 months ,ranging from 0 month to 24 months .Results The reliability analysis indicates that the Cronbach'sαcoefficient was 0 .797 ,except for the well-being and happiness ,education ,whose coefficients are respectively 0 .303 ,and 0 .341 ,all of the other sundomainscoefficient were greater than 0 .5 ,indicating the internal consistency was good .Test -retest reliability of the scale Cronbach'sαwas satisfactory .All subdomains and total score of the scale coefficients were greater than 0 .70(P<0 .01) .The validity analysis indicated that the pearson correlation coefficients among the total scale and the 8 subdo-mains were 0 .395~0 .992 ,the correlation coefficients among each subdomains were 0 .09~0 .654 ,which confirmed with the psychological characteristics ,proving its good structure validity .Conclusion The Chinese version of the PP show s good reliability and validity and can be used to evaluation the quality of life in mandarin CI children.

The protective action and its mechanism of 5-hydroxy-1 H-indazole in SH-SY5 Y cells / 中国药理学通报

Aim To study the protection and possible mechanism of 5-hydroxy-1 H-indazole against 1-methyl-4-phenylpyridinium iodide ( MPP+)-induced SH-SY5 Y cell apoptosis. Methods An apoptotic model was es-tablished in human neuroblastoma SH-SY5 Y by MPP+in vitro. MTT analysis was used to evaluate the protec-tive effect of 5-hydroxy-1H-indazole. Immunochemistry and Hoechst33258 nuclear staining were used to ob-serve the neuroprotection and anti-apoptosis of 5-hy-droxy-1H-indazole. Western blot was used to detect the levels of P-tau ( Ser396 ) closely related to neuronal apoptosis and its upstream kinases:P-GSK-3β and CDK5 . Results MPP+ induced activation of GSK-3β, increase of activity of CDK5 , tau hyperphosphory-lation and neuronal cell apoptosis. However,5-hydrox-y-1 H-indazole reduced the activities of GSK-3β and CDK5,then decreased the level of tau hyperphosphory-lation and inhibited MPP+-induced SH-SY5 Y cells ap-optosis. Conclusions 5-hydroxy-1H-indazole could attenuate MPP+-induced SH-SY5 Y neuronal cell apop-tosis. Possible mechanism is that 5-hydroxy-1H-in-dazole inhibits GSK-3βand CDK5 two signal transduc-tion pathways to lower the level of tau phosphorylation, then plays a role of neuroprotection.

Effects of propofol treatment on neuroapoptosis in primary cultured cortical neurons / 临床麻醉学杂志

Objective To investigate the effect of propofol exposure on neuroapoptosis in pri-mary cultured cortical neurons and its mechanisms.Methods Cortical neurons were primarily cultured for seven days,then divided into two groups:control group (treated with equal volume of 20% in-tralipid),propofol-treated group (treated with 500 μmol/L propofol).The neurons were treated for 12 h.The neuron viability was determined by MTT.Neuroapoptosis was identified by Hoechest 33 258 dying.Mitochondrial membrane potential was measured by the fluorescent dye rhodamine 123 (Rh123).Western blot was performed to detect the level of cyt-c and cleaved-caspase-3.Results Neu-rons survival rate (54.4%±6.4%)in the propofol group was significantly lower than that of control group (99.8% ± 4.1%) (P < 0.05 ), the rate of neuronal apoptosis (46.5% ± 5.3%) was significantly higher than that of control group (7.2%±0.9%)(P <0.05),mitochondrial membrane potential (59.6%±4.3%)was significantly lower than that of the control group (99.9% ± 5.7%) (P <0.05 ),cyt-C protein level (0.38 ± 0.03 )was significantly higher than that of control group (0.1 5±0.02)(P < 0.05 ),level of cleaved-caspase-3 protein level (0.46 ± 0.04)was significantly higher than that of control group (0.13±0.02)(P <0.05).Conclusion Propofol induces neuroapo-tosis in primary cultured cortical neurons,which is associated with the decreased level of MPP and the increase levels of cyt-c and cleaved-caspase-3.

Expression of CXCL8 and its mRNA in peripheral blood of children with Myco-plasmal pneumonia / 中国免疫学杂志

Objective:To study the expression of CXCL 8 in the serum and CXCL8 mRNA in the peripheral blood mononuclear cells(PBMCs) of the children with Mycoplasma pneumoniae pneumonia (MPP) and its clinical significance.Methods: Forty-eight children(severe cases 12,light cases 36) with MPP were recruited from October 2013 to March 2015 in the Maternal and Child Health-Care Hospital of Huainan.The concentration of the CXCL8 in serum and the level of CXCL8 mRNA in the PBMCs were measured by enzyme linked immunosorbent assay ( ELISA) and polymerase chain reaction ( PCR).Taking GAPDH as the internal reference ,the ratio of lgcDNA/lgGAPDH was regarded as the extreme level of CXCL 8 mRNA.Results: The serum level of CXCL8 and expression of CXCL8 mRNA in PBMCs in the children with MPP were ( 298.917 ±51.860 ) pg/ml and ( 1.848 ±0.525 ) lgcDNA/lgGAPDH.Compared with the normal control ,there were significant differences between the two groups ( P0.05).However, the expression of CXCL8 mRNA in peripheral blood of the children with severe illness was significantly higher than those in light cases (P<0.05).Intravenous infusion of Erythromycin was provided in the acute phase for seven to ten days ,so that the children′s condition could be significantly controlled , and the symptoms of pulmonary inflammation were also relieved .Followed by the use of sequential therapy of Azithromycin for about two to three weeks ,the children′s condition were gradually from acute stage to recovery stage .At this time,the CXCL8 and its mRNA levels in peripheral blood of the sick children were all significantly decreased comparing with those in the acute stage(P<0.05).Conclusion: The expression of CXCL8 and its mRNA were increased in the peripheral blood of the sick children with Mycoplasma pneumonia ,and also correlated with the severity of the disease .CXCL8 can participate in the pathogenesis of Mycoplasma pneumonia ,and has a certain cue effect on the severity and prognosis of the disease .Azithromycin can reduce the content of CXCL8 in serum of the sick children via the pathway of inhibiting the proliferation of Mycoplasma pneumoniae ,and down regulate the expression of mRNA ,so that the immune injury mediated by Mycoplasma pneumoniae may be gradually inhibited .

Glucose Levels in Culture Medium Determine Cell Death Mode in MPP+-treated Dopaminergic Neuronal Cells

We previously demonstrated that 1-methyl-4-phenylpyridinium (MPP+) causes caspase-independent, non-apoptotic death of dopaminergic (DA) neuronal cells. Here, we specifically examined whether change of glucose concentration in culture medium may play a role for determining cell death modes of DA neurons following MPP+ treatment. By incubating MN9D cells in medium containing varying concentrations of glucose (5~35 mM), we found that cells underwent a distinct cell death as determined by morphological and biochemical criteria. At 5~10 mM glucose concentration (low glucose levels), MPP+ induced typical of the apoptotic dell death accompanied with caspase activation and DNA fragmentation as well as cell shrinkage. In contrast, MN9D cells cultivated in medium containing more than 17.5 mM (high glucose levels) did not demonstrate any of these changes. Subsequently, we observed that MPP+ at low glucose levels but not high glucose levels led to ROS generation and subsequent JNK activation. Therefore, MPP+-induced cell death only at low glucose levels was significantly ameliorated following co-treatment with ROS scavenger, caspase inhibitor or JNK inhibitor. We basically confirmed the quite similar pattern of cell death in primary cultures of DA neurons. Taken together, our results suggest that a biochemically distinct cell death mode is recruited by MPP+ depending on extracellular glucose levels.

The role of α-synuclein ubiquitination in its selectivity of degradation pathway / 实用医学杂志

Objective To investigate SIAH′s role in α-synuclein degradation, formation of Lewy bodies and neuronal death. Methods Proliferative activity of PC12 cells was measures by MTT assay after treatment with MPP and Rapamycin. Western Blot was applied determine the protein expression of LC3-Ⅱ, E1, SIAH-1, P53 and α-synucleinto. PCR was applied to measure protein related mRNA levels. Immunofluorescent techniques were used to detect the distribution of α-synuclein, SIAH-1 and LC3 in cells after SIAH antibody processing. Results MPP+ treatment increased α-synuclein, E1 expression and SIAH-1 activity, however, LC3-Ⅱ, P53 and α-synuclein protein levels decreased significantly. Anti-SIAH-1 antibody treatment reversed this trend, with E1 significantly increased. Rapamycin treatment reduced SIAH-1 and α-synuclein levels in the MPP+ group. SIAH-1 antibody significantly decreased the positive immuno-stain of α-synuclein, SIAH-1 and LC3, suggesting loss of co-localization. Conclusions Anti-SIAH-1 supports the clearance of non-aggregated α-synuclein by the UPS. SIAH plays a key role in the pathogenesis of Parkinson′s disease and is a potential therapeutic target of neurodegenerative diseases.

Protection of 20-hydroxyecdysone on SH-SY5Y cells from 1-methy-4-phenylpyridinium-induced injury / 中国药学杂志

OBJECTIVE: To investigate the protective effect and probable mechanism of 20-Hydroxyecdysone on SH-SY5Y cells injured by MPP+. METHODS: MPP+ induced SH-SY5Y cells injury model was established. 20-Hydroxyecdysone was added into the culture to test its protective effect. The morphological changes of cells were observed. Cell viability was detected by method of MTT. The contents of LDH, MDA and activity of SOD were inspected by kits. Apoptosis rate of cells was detected by flow cytometry. RESULTS: Compared with MPP+ group, 20-Hydroxyecdysone group (50, 100, 150 μmol·L-1) alleviated the damage of SH-SY5Y cells induced by MPP+, significantly improved cell survival rate, reduced the release of LDH, increased the activity of SOD, decreased the contents of MDA and reduced the apoptosis of cells. CONCLUSION: 20-Hydroxyecdysone has a significant protective effect on SH-SY5Y cells injured by MPP+. The probable mechanism may be anti-oxidation and anti-apoptosis.

Inhibition of Tau phosphorylation protects SH-SY5Y cells from MPP +-induced apoptosis by 6-Hydroxy-1H-indazole / 中国药理学通报

Aim To study the protective effect of 6-Hydroxy-1 H-indazole via inhibition of Tau phosphoryla-tion on MPP +-induced SH-SY5Y cells apoptotsis. Methods An apoptotic model induced by 1 -methy-4-phenylpridnium ion (MPP +)was established in cul-tured human neuroblastoma SH-SY5Y in vitro.MTT a-nalysis was used to evaluate the protective effect of pre-treatment of cells with 6-Hydroxy-1 H-indazole for 2 h. Hoechst33258 staining was used to observe apoptotic situation.Immunohistochemistry was used to detect the p-Tau (Ser396)expression.Results The viability of cells exposed to 200 μmol · L -1 MPP + for 48h was (47.80 ±0.84)% (P <0.01 ),MPP + induced phos-phorylation of Tau at Ser396 and neuronal apoptosis, while 6-Hydroxy-1 H-indazole inhibited MPP +-induced cellular apoptosis,increased the number of TH-positive cells via inhibiting Tau phosphorylation.Conclusion These results indicate that Tau may be a new target used to cure neurodegenerative disorders such as PD.

Neuroprotective Effect of Chebulagic Acid via Autophagy Induction in SH-SY5Y Cells

Autophagy is a series of catabolic process mediating the bulk degradation of intracellular proteins and organelles through formation of a double-membrane vesicle, known as an autophagosome, and fusing with lysosome. Autophagy plays an important role of death-survival decisions in neuronal cells, which may influence to several neurodegenerative disorders including Parkinson's disease. Chebulagic acid, the major constituent of Terminalia chebula and Phyllanthus emblica, is a benzopyran tannin compound with various kinds of beneficial effects. This study was performed to investigate the autophagy enhancing effect of chebulagic acid on human neuroblastoma SH-SY5Y cell lines. We determined the effect of chebulagic acid on expression levels of autophagosome marker proteins such as, DOR/TP53INP2, Golgi-associated ATPase Enhancer of 16 kDa (GATE 16) and Light chain 3 II (LC3 II), as well as those of its upstream pathway proteins, AMP-activated protein kinase (AMPK), mammalian target of rapamycin (mTOR) and Beclin-1. All of those proteins were modulated by chebulagic acid treatment in a way of enhancing the autophagy. Additionally in our study, chebulagic acid also showed a protective effect against 1-methyl-4-phenylpyridinium (MPP+) - induced cytotoxicity which mimics the pathological symptom of Parkinson's disease. This effect seems partially mediated by enhanced autophagy which increased the degradation of aggregated or misfolded proteins from cells. This study suggests that chebulagic acid is an attractive candidate as an autophagy-enhancing agent and therefore, it may provide a promising strategy to prevent or cure the diseases caused by accumulation of abnormal proteins including Parkinson's disease.

Protective effects of paeoniflorin on dopaminergic neurons in brain slice of substantia nigra treated with 1-methyl-4-phenylpytidinium / 中国药理学通报

Aim To study the protective effects of Paeoniflorin (PF) on dopaminergic neurons in brain slice of substantia nigra treated with MPP~+ and to investigate the transcription of alpha-synuclei (α-syn) mRNA.Methods The organatypic brain slice culture of substantia nigra prepared from neonatal SD rats was placed on Millicell-CM porous membranes and cultured to day-10.Then the cultrues of slice were treated with different concentrations (0.1,0.5,1.0 mmol·L~(-1)) of MPP~+ for 24 h.Some of the cultrues treated with 0.5 mmol·L~(-1) MPP~+ also received PF (1 or 10 μmol·L~(-1)).Slices cultured in normal medium were used as vehicle control.The tyrosine hydroxylase (TH) immunohistochemical staining with the cell counting was used to determine the dopaminergic neruons.The transcription of α-syn mRNA was examined by real-time quantitative RT-PCR.Results MPP~+(0.1,0.5,1.0 mmol·L~(-1)) exposure markedly decreased the number of TH~+ cells in a dose-dependent manner (P<0.05 or P<0.01) and sharply induced the transcription of α-syn mRNA (P<0.01) in slices treated with 0.5 mmol·L~(-1) MPP~+.The addition of PF (10 μmol·L~(-1)) to MPP~+-treated slices significantly increased dopaminergic neurons survival (P<0.01) and downregulated the transcription of α-syn mRNA significantly (P<0.05).Conclusion PF can effectively inhibit the injury of dopaminergic neurons induced by MPP~+ on brain slice of substantia nigra and downregulate the transcription of alpha-synuclein.

The protective action of chromomycin on dopaminergic neurons / 中国药理学通报

Aim To study the effect of chromomycin on MPP~+-induced dopaminergic neuronal apoptosis.Methods An apoptosis model induced by 1-methyl-4-phenylpridnium ion(MPP~+)was established in cultured fetal mesencephalic neurons in vitro.Dopaminergic neuronal apoptosis was detected by Hoechst 33258 staining and phospho-Tau levels were detected by immunofluorescence.Results 10 μmol·L~(-1) MPP~+ hyperphosphorylated Tau at Ser396 and induced dopaminergic neuronal apoptosis.Chromomycin increased the number of TH-positive cells via inhibiting Tau phosphorylation.Conclusion These results indicate thatchromomycin inhibits Tau phosphorylation at Ser396 and therefore protects dopaminergic mesencephalic neurons from apoptosis induced by MPP+,which suggests that Chromomycin may be used to cure neurodegenerative disorders such as Parkinson's disease in clinic.

Glycyrrhizin Attenuates MPTP Neurotoxicity in Mouse and MPP+-Induced Cell Death in PC12 Cells

The present study examined the inhibitory effect of licorice compounds glycyrrhizin and a metabolite 18 beta-lycyrrhetinic acid on the neurotoxicity of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) in the mouse and on the 1-methyl-4-phenylpyridinium (MPP+-induced cell death in differentiated PC12 cells. MPTP treatment increased the activities of total superoxide dismutase, catalase and glutathione peroxidase and the levels of malondialdehyde and carbonyls in the brain compared to control mouse brain. Co-administration of glycyrrhizin (16.8 mg/kg) attenuated the MPTP effect on the enzyme activities and formation of tissue peroxidation products. In vitro assay, licorice compounds attenuated the MPP+induced cell death and caspase-3 activation in PC12 cells. Glycyrrhizin up to 100 micrometer significantly attenuated the toxicity of MPP+ Meanwhile, 18beta-lycyrrhetinic acid showed a maximum inhibitory effect at 10 micrometer; beyond this concentration the inhibitory effect declined. Glycyrrhizin and 18beta-lycyrrhetinic acid attenuated the hydrogen peroxide- or nitrogen species-induced cell death. Results from this study indicate that glycyrrhizin may attenuate brain tissue damage in mice treated with MPTP through inhibitory effect on oxidative tissue damage. Glycyrrhizin and 18 beta-lycyrrhetinic acid may reduce the MPP+toxicity in PC12 cells by suppressing caspase-3 activation. The effect seems to be ascribed to the antioxidant effect.