OBJECTIVE: Mitophagy is known to contribute towards progression of Parkinson's disease. Korean red ginseng (KRG) is a widely used medicinal herb in East Asia, and recent studies have reported that KRG prevents 1-methyl-4-phenylpyridinium ion (MPP METHODS: SH-SY5Y cells were incubated with KRG for 24 h, and subsequently exposed to MPP RESULTS: MPP CONCLUSION KRG effectively prevents MPP
1-Methyl-4-phenylpyridinium/toxicity* ; Apoptosis ; Cell Line, Tumor ; Mitochondria ; Mitophagy ; Panax ; Reactive Oxygen Species

Gastrodiae Rhizoma-Uncariae Ramulus cum Uncis is the most frequently used herbal pair in the treatment of Parkinson's disease(PD). Gastrodin and isorhynchophylline are important components of Gastrodiae Rhizoma-Uncariae Ramulus cum Uncis herb pair with anti-Parkinson mechanism. This study aimed to investigate the effect of gastrodin combined with isorhynchophylline on 1-methyl-4-phenylpyridinium(MPP~+)-induced apoptosis of PC12 cells and their antioxidant mechanism. The leakage of lactate dehydrogenase(LDH) from cells to media was analyzed by spectrophotometry. Apoptotic cells were labeled with Annexin V-fluorescein isothiocyanate(FITC) and propidium iodide(PI) and analyzed by flow cytometry. The cell cycle was analyzed using propidium iodide(PI) staining. Lipid peroxidation(LPO) level was analyzed by spectrophotometry. The mRNA expression of caspase-3 was examined by Real-time RT-PCR. The protein expressions of heme oxygenase 1(HO-1) and NADPH: quinoneoxidore-ductase 1(NQO-1) were determined by Western blot. Gastrodin combined with isorhynchophylline reduced the percentage of Annexin V-positive cells and cell cycle arrest in MPP~+-induced PC12 cells. Gastrodin combined with isorhynchophylline down-regulated the mRNA expression of caspase-3, up-regulated the protein expressions of HO-1 and NQO-1, and reduced LPO content in MPP~+-induced PC12 cells. PD98059, LY294002 or LiCl could partially reverse these changes pretreated with gastrodin combined with isorhynchophylline, suggesting that gastrodin combined with isorhynchophylline inhibited MPP~+-induced apoptosis of PC12 cells and oxidative stress through ERK1/2 and PI3 K/GSK-3β signal pathways. Our experiments showed that gastrodin combined with isorhynchophylline could down-re-gulate the mRNA expression of caspase-3 and up-regulate the protein expressions of HO-1 and NQO-1, so as to reduce oxidative stress and inhibit apoptosis.
1-Methyl-4-phenylpyridinium/toxicity* ; Animals ; Antioxidants ; Apoptosis ; Benzyl Alcohols ; Cell Survival ; Glucosides ; Glycogen Synthase Kinase 3 beta ; Oxindoles ; PC12 Cells ; Rats

OBJECTIVETo investigate the protective effect of six Kaixin San formulas on simulated cells model of depression, Alzheimer's disease and Parkinson's disease.

METHODThe in vitro simulated cells model of depression, Alzheimer's disease and Parkinson's disease was established by injuring SH-SY5Y cells with corticosterone (0.4 mmol x L(-1)) , injuring PC12 cells with neurotoxic amyloid peptide (Abeta25-35) (20 micromol x L(-1)) and injuring SH-SY5Y cells with 1-methyl-4-phenylpyridinium ion (MPP+) (250 micromol x L(-1)). The cell survival rate was assayed with MTT method and the degree of cell injury was detected with LDH.

RESULT100, 500 mg x L(-1) Dingzhixiao Wan prepared as mentioned in Beiji Qianjin Yaofang could significantly increase the survival ratio of SH-SY5Y cells injured by corticosterone and reduce LDH concentration released. All of the Kaixin San formulas could significantly increase the survival ratio of PC12 cells injured by Abeta25-35 and reduce LDH concentration released. Particularly, Kaixin San (10, 100, 500 mg L(-1)) prepared as mentioned in Beiji Qianjin Yaofang shown the best effect. And 500 mg x L(-1) Fushen Wan prepared as mentioned in Gujin Luyan could significantly increase survival ratio of SH-SY5Y cell injured by MPP and reduce LDH concentration released.

CONCLUSIONDingzhixiao Wan prepared as mentioned in Beiji Qianjin Yaofang could protect corticosterone-induced SH-SY5Ycells injury, showing a potential antidepressant effect. All of the six Kaixin San formulas could protect Abeta25-35-induced PC12 cells injury, but Kaixin San prepared as mentioned in Beiji Qianjin Yaofang shown the best potential effect for Alzheimer's disease. Fushen Wan prepared as mentioned in Gujin Luyan could protect MPP(+)-induced SH-SY5Y cells injury to some extent.

1-Methyl-4-phenylpyridinium ; toxicity ; Alzheimer Disease ; drug therapy ; Amyloid beta-Peptides ; toxicity ; Animals ; Cell Survival ; drug effects ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Neurons ; cytology ; drug effects ; Neuroprotective Agents ; pharmacology ; PC12 Cells ; Parkinson Disease ; drug therapy ; Peptide Fragments ; toxicity ; Rats

OBJECTIVETo investigate the toxic effect of environmental neurotoxin MPP+ to C. elegans and identify the mechanisms that cause the toxicity.

METHODSHuman alpha-synuclein transgenic C. elegans was used as the animal model, the toxic effect of MPP+ to dopamine (DA) neurons and the lifespan of worms was tested. The worms were feed with OP50 to determine whether ATP increase can rescue the worm from toxicity. ATP level and aberrant protein accumulation were analyzed in the MPP+ treated worms with or without OP50 addition.

RESULTSWe found that MPP+ induced DA cell death and worm lethality, which could be prevented by OP50 treatment. OP50 exerted the protective effect by up-regulating ATP level, even though it also induced accumulation of alpha-synuclein. Despite the undefined role of protein aggregation to the cell death, our results showed that the toxicity of MPP+ was mainly caused by the ATP depletion in the alpha-synuclein transgenic C. elegans.

CONCLUSIONMPP+ could induce DA neuronal death and worm lethality in alpha-synuclein transgenic C. elegans; Compared with the aggregation of alpha-synuclein, the major cause of MPP+ toxicity appeared due to ATP depletion.

1-Methyl-4-phenylpyridinium ; toxicity ; Adenosine Triphosphate ; deficiency ; metabolism ; Animals ; Animals, Genetically Modified ; Caenorhabditis elegans ; Caenorhabditis elegans Proteins ; drug effects ; metabolism ; Cell Death ; Disease Models, Animal ; Dopamine ; metabolism ; Herbicides ; toxicity ; Humans ; MPTP Poisoning ; metabolism ; mortality ; Neurons ; drug effects ; metabolism ; alpha-Synuclein ; drug effects ; genetics ; metabolism

OBJECTIVETo investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP(+)) and to explore the potential mechanisms.

METHODSThe viability and apoptosis of PC12 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4',6'-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phosphorylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2).

RESULTSThe cell viability decreased and the number of apoptotic cells increased dramatically in MPP(+) group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP(+)-treated PC12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC12 cells induced by HPP.

CONCLUSIONHPP protects PC12 cells against MPP(+) toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.

1-Methyl-4-phenylpyridinium ; toxicity ; 14-3-3 Proteins ; biosynthesis ; Animals ; Apoptosis ; drug effects ; physiology ; Blotting, Western ; Cell Survival ; drug effects ; Enzyme-Linked Immunosorbent Assay ; Hydrogen Peroxide ; pharmacology ; Mitogen-Activated Protein Kinase 1 ; metabolism ; Mitogen-Activated Protein Kinase 3 ; metabolism ; Neurons ; drug effects ; metabolism ; pathology ; PC12 Cells ; Phosphorylation ; Rats ; Signal Transduction ; drug effects ; physiology ; Up-Regulation ; p38 Mitogen-Activated Protein Kinases ; metabolism

The purpose of our research was to evaluate the protective effect of the effective part of Acanthopanacis senticosus (AS) on the damage of PC12 cells induced by MPP+, an in vitro cell model for Parkinson's disease. Cell viability and apoptosis of PC12 cells induced by MPP' were assayed by MTT and flow cytometry respectively in the presence or absence of the effective part of AS. The contents of lactate dehydrogenase (LDH), nitric oxide (NO), nitric oxide synthase (NOS) and malondialdehyde (MDA) were determined by UV spectrophotometer. Our study showed that the survival rate of PC12 cells was markedly increased while cell apoptosis was decreased in the range of 200 to 400 mg x L(-1) of the effective part of AS. The contents of LDH, NO, NOS, MDA were reduced. Our experimental results indicated that the effective part of AS had the protective effect on the damage of PC12 cells induced by MPP+. The underlying mechanisms might be the combination of reduction of LDH leakage and decreases in the contents of NO, NOS and MDA, and finally prevent the apoptosis in PC12 cells and increase the cell survival rate.
1-Methyl-4-phenylpyridinium ; toxicity ; Animals ; Apoptosis ; drug effects ; Araliaceae ; chemistry ; Cell Survival ; drug effects ; Disease Models, Animal ; Drugs, Chinese Herbal ; administration & dosage ; Humans ; Malondialdehyde ; metabolism ; Neurons ; cytology ; drug effects ; metabolism ; Neuroprotective Agents ; administration & dosage ; Nitric Oxide ; metabolism ; PC12 Cells ; Parkinson Disease ; drug therapy ; metabolism ; physiopathology ; Rats

OBJECTIVEThe neuroprotective effect of erythropoietin (EPO) against 1-methyl-4-phenylpyridinium (MPP(+))-induced oxidative stress in cultured PC12 cells, as well as the underlying mechanism, were investigated.

METHODSPC12 cells impaired by MPP(+) were used as the cell model of Parkinson's disease. Methyl thiazolyl tetrazolium (MTT) was used to assay the viability of the PC12 cells exposed to gradient concentrations of EPO, and the terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) assay was used to analyze the apoptosis ratio of PC12 cells. The expression of Bcl-2 and Bax in PC12 cells were examined by Western blot, and the reactive oxygen species (ROS), the mitochondrial transmembrane potential and the activity of caspase-3 in each group were detected by spectrofluorometer.

RESULTSTreatment of PC12 cells with MPP(+) caused the loss of cell viability, which may be associated with the elevation in apoptotic rate, the formation of ROS and the disruption of mitochondrial transmembrane potential. It was also shown that MPP(+) significantly induced the upregulation of Bax/Bcl-2 ratio and the activation of caspase-3. In contrast, EPO significantly reversed these responses and had the maximum protective effect at 1 U/mL.

CONCLUSIONThe inhibitive effect of EPO on the MPP(+)-induced cytotoxicity may be ascribed to its anti-oxidative property and anti-apoptotic activity, and EPO may provide a useful therapeutic strategy for treatment of neurodegenerative diseases such as Parkinson's disease.

1-Methyl-4-phenylpyridinium ; toxicity ; Analysis of Variance ; Animals ; Apoptosis ; drug effects ; Caspase 3 ; metabolism ; Cell Survival ; drug effects ; Dose-Response Relationship, Drug ; Drug Interactions ; Erythropoietin ; pharmacology ; Flow Cytometry ; methods ; Herbicides ; toxicity ; In Situ Nick-End Labeling ; methods ; Membrane Potential, Mitochondrial ; drug effects ; Neuroprotective Agents ; pharmacology ; PC12 Cells ; drug effects ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Rats ; Reactive Oxygen Species ; metabolism ; Tetrazolium Salts ; Thiazoles ; bcl-2-Associated X Protein ; genetics ; metabolism

OBJECTIVENeuroinflammation with microglial activation has been implicated to have a strong association with the progressive dopaminergic neuronal loss in Parkinson's disease (PD). The present study was undertaken to evaluate the activation profile of microglia in 1-methyl-4-phenyl pyridinium (MPP+)-induced hemiparkinsonian rats. Triptolide, a potent immunosuppressant and microglia inhibitor, was then examined for its efficacy in protecting dopaminergic neurons from injury and ameliorating behavioral disabilities induced by MPP+.

METHODSThe rat model of PD was established by intranigral microinjection of MPP+. At baseline and on day 1, 3, 7, 14, 21 following MPP+ injection, the degree of microglial activation was examined by detecting the immunodensity of OX-42 (microglia marker) in the substantia nigra (SN). The number of viable dopaminergic neurons was determined by measuring tyrosine hydroxylase (TH) positive neurons in the SN. Behavioral performances were evaluated by counting the number of rotations induced by apomorphine, calculating scores of forelimb akinesia and vibrissae-elicited forelimb placing asymmetry.

RESULTSIntranigral injection of MPP+ resulted in robust activation of microglia, progressive depletion of dopaminergic neurons, and ongoing aggravation of behavioral disabilities in rats. Triptolide significantly inhibited microglial activation, partially prevented dopaminergic cells from death and improved behavioral performances.

CONCLUSIONThese data demonstrated for the first time a neuroprotective effect of triptolide on dopaminergic neurons in MPP+-induced hemiparkinsonian rats. The protective effect of triptolide may, at least partially, be related to the inhibition of MPP+-induced microglial activation. Our results lend strong support to the use of immunosuppressive agents in the management of PD.

1-Methyl-4-phenylpyridinium ; antagonists & inhibitors ; toxicity ; Animals ; Biomarkers ; metabolism ; CD11b Antigen ; analysis ; metabolism ; Cell Count ; Cell Survival ; drug effects ; physiology ; Disability Evaluation ; Diterpenes ; pharmacology ; therapeutic use ; Dopamine ; metabolism ; Encephalitis ; drug therapy ; immunology ; prevention & control ; Epoxy Compounds ; pharmacology ; therapeutic use ; Gliosis ; drug therapy ; immunology ; prevention & control ; Herbicides ; antagonists & inhibitors ; toxicity ; Immunosuppression ; methods ; Immunosuppressive Agents ; pharmacology ; therapeutic use ; Male ; Microglia ; drug effects ; immunology ; Neurons ; drug effects ; immunology ; pathology ; Parkinsonian Disorders ; drug therapy ; immunology ; physiopathology ; Phenanthrenes ; pharmacology ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Substantia Nigra ; drug effects ; immunology ; physiopathology ; Treatment Outcome ; Tyrosine 3-Monooxygenase ; analysis ; metabolism