Amyloid beta-Peptides ; toxicity ; Animals ; Drugs, Chinese Herbal ; pharmacology ; Estradiol ; pharmacology ; PC12 Cells ; Peptide Fragments ; toxicity ; Rats

OBJECTIVEAnthracyclines (ANT) are effective for leukemia and solid tumors. However the long-term life quality of patients is seriously affected by ANT-related cardiotoxicity. The aim of this study was to evaluate the value of two dimension echocardiography (2DE) and serum biochemical indicators in monitoring ANT-related cardiotoxicity.

METHODSSeventy children who received ANT chemotherapy (ANT dose: 124 ± 73 mg/m2) and were followed up for 22 ± 13 months were enrolled. 2DE with aspects of conventional indexes (left ventricular diameter and wall thickness, ejection fraction, E/A), myocardial performance index (MPI) and tissue Doppler imaging (TDI) were performed. Serum levels of troponin (CTnI) and brain natriuretic peptide (BNP) were measured. Thirty-seven healthy children served as the control group.

RESULTSThere were no significant differences in conventional indexes of 2DE between the ANT and the control groups. The MPI of left and right ventricular in the ANT group increased significantly compared with that in the control group (0.237 ± 0.06 vs 0.203 ± 0.06, 0.171 ± 0.05 vs 0.140 ± 0.04 respectively; P<0.01). TDI showed the late diastolic peak velocity in the basal and middle sections of left ventricular, interventricular septum and right ventricular in the ANT group were significantly higher than the controls. There were significant differences in the ratio of early to late diastolic peak velocity of the middle section of left ventricular and the basal and middle sections of the interventricular septum between the two groups (P<0.05). The changes of MPI and TDI became more obvious with the increased dose of ANT. There were no significant differences in serum CtnI and BNP levels between the two groups.

CONCLUSIONSThe heart function of patients who received ANT chemotherapy needs to be monitored for a long term. MPI and TDI can be used as early indexes for monitoring the heart function.

Adolescent ; Anthracyclines ; toxicity ; Child ; Child, Preschool ; Dose-Response Relationship, Drug ; Echocardiography ; Female ; Heart ; drug effects ; Humans ; Infant ; Male ; Natriuretic Peptide, Brain ; blood ; Peptide Fragments ; blood ; Troponin I ; blood

OBJECTIVETo examine the protective effect of ecdysterone (ECR) against beta-amyloid peptide fragment(25-35) (Abeta(25-35))-induced PC12 cells cytotoxicity, and to further explore its mechanism.

METHODSExperimental PC12 cells were divided into the Abeta group (treated by Abeta(25-35) 100 micromol/L), the blank group (untreated), the positive control group (treated by Vit E 100 micromol/L after induction) and the ECR treated groups (treated by ECR with different concentrations of 1, 50 and 100 micromol/L). The damaged and survival condition of PC12 cells in various groups was monitored by lactate dehydrogenase (LDH) release and MTT assay. The content of malondialdehyde (MDA) was measured by fluorometric assay to indicate the lipid peroxidation. And the antioxidant enzymes activities in PC12 cells, including superoxide dismutases (SOD), catalase (CAT) and glutathione peroxidase (GSH-Px), were detected respectively.

RESULTSAfter PC12 cells were treated with Abeta(25-35) (100 micromol/L) for 24 hrs, they revealed a great decrease in MTT absorbance and activity of antioxidant enzymes, including SOD, CAT and GSH-Px as well as a significant increase of LDH activity and MDA content in PC12 cells (P < 0.01). When the cells was pretreated with 1-100 micromol/L ECR for 24 hrs before Abeta(25-35) treatment, the above-mentioned cytotoxic effect of Abeta(25-35) could be significantly attenuated dose-dependently, for ECR 50 micromol/L, P < 0.05 and for ECR 100 micromol/L, P < 0.01. Moreover, ECR also showed significant inhibition on the Abeta(25-35) induced decrease of SOD and GSH-Px activity, but not on that of CAT.

CONCLUSIONECR could protect PC12 cells from cytotoxicity of Abeta(25-35), and the protective mechanism might be related to the increase of SOD and GSH-Px activities and the decrease of MDA resulting from the ECR-pretreatment.

Amyloid beta-Peptides ; toxicity ; Animals ; Catalase ; analysis ; Ecdysterone ; pharmacology ; Glutathione Peroxidase ; analysis ; L-Lactate Dehydrogenase ; analysis ; Malondialdehyde ; analysis ; PC12 Cells ; Peptide Fragments ; toxicity ; Rats

OBJECTIVETo compare the toxicity of mechanism beta amyloid peptide (Abeta) 25-35 and 31-35 to cultured rat cortical neurons.

METHODSThe primary rat cerebral cortical neurons of rat were cultured 48 hours and randomly divided into control, Abeta25-35 (25 micromol/L)and Abeta31-35 (25 micromol/L) treated groups. After twenty four hours culturing, the cells were collected MTT assay was performed to measure the viability of cultured neurons. The mitochondrial membrane potential was determined to investigate the alteration of mitochondrial structure and function of neurons by laser scanning confocal microscope. The DNA damage of neurons was measured by single cell gel electrophoresis. The expressions of Bcl-2, Bax and p53 gene were measured by reverse transcriptase polymerase chain reaction (RT-PCR). Each experiment was repeated three times.

RESULTSThe absorbance (0.746 +/- 0.071, 0.811 +/- 0.083) and fluorescence intensity (3.050 +/- 0.240, 2.806 +/- 0.203) of neurons in Abeta25-35 and 31-35 treated group were significantly lower (t(A) were 4.023 and 5.401, t(fluorescence intensity) were 9.524 and 7.589 respectively, P < 0.01) than those in control group (1.038 +/- 0.125 and 4.280 +/- 0.358 respectively). The percentage of comet cells (59.0%, 48.5%) and tail length (57.3 +/- 4.7, 54.2 +/- 6.8) microm in Abeta25-35 and 31-35 treated group were significantly higher (chi(2)(comet cell) were 99.397 and 137.071, t(tail length) were 19.058 and 29.173 respectively, P < 0.01) than those in control group (4.5% and (5.2 +/- 1.1) microm respectively). Compared with control group (Bax/Bcl-2 ratio 0.2090 +/- 0.0991, p53/beta-actin ratio 1.6560 +/- 0.0853), the Bax/Bcl-2 ratio (t value were 2.429 and 2.356 respectively, P < 0.05) and expressions of p53 (t value were 2.366 and 2.503 respectively, P < 0.05) gene were significantly increased (P < 0.05) in Abeta25-35 (Bax/Bcl-2 ratio 1.2774 +/- 0.0762, p53/beta-actin ratio 2.0284 +/- 0.2223) and Abeta31-35 (Bax/Bcl-2 ratio 1.0330 +/- 0.0683, p53/beta-actin ratio 1.9505 +/- 0.2725) treated group.

CONCLUSIONSNeurotoxicity-induced by Abeta31-35 in cortical neurons is similar to that induced by Abeta25-35, which is possibly related to its direct neurotoxic and apoptotic effects to neurons.

Amyloid beta-Peptides ; toxicity ; Animals ; Apoptosis ; drug effects ; Cells, Cultured ; Cerebral Cortex ; cytology ; Neurons ; drug effects ; Peptide Fragments ; toxicity ; Rats ; Rats, Wistar

OBJECTIVETo explore the biological activity of recombinant human single-chain antibody against amyloid beta peptide in vitro.

METHODSHuman single-chain antibody against amyloid beta peptide was obtained from recombinant bacteria. The antigen-binding activity of this antibody was measured by enzyme-linked immunosorbent assay (ELISA) and competitive ELISA. Human neuroblastoma SH-SY5Y cells were used as cell models to test the protective role of human single-chain antibody against amyloid beta peptide.

RESULTSRecombinant human single-chain antibody was mainly located in the insoluble inclusion bodies of bacteria. The antibody was dissolved by urea and purified by metal affinity chromatography as active form to bind synthetic amyloid beta peptide 40 or amyloid beta peptide 42. The improvement of the survival rates of human neuroblastoma cells was significantly superior in amyloid peptide 42 plus equimolar antibody group than in amyloid peptide 42 group (P < 0.05), and was significantly superior in the amyloid peptide 40 plus equimolar antibody group than in amyloid peptide 40 group (P < 0.01).

CONCLUSIONThe recombinant human single-chain antibody against beta amyloid peptide 40 from E. coli can partially inhibit the neurotoxicity effect of amyloid beta peptide in vitro.

Amyloid beta-Peptides ; immunology ; metabolism ; toxicity ; Cell Line, Tumor ; Cell Survival ; drug effects ; Humans ; Peptide Fragments ; metabolism ; toxicity ; Protein Binding ; Recombinant Proteins ; pharmacology ; Single-Chain Antibodies ; pharmacology

OBJECTIVETo investigate the effect of berberine on expressions of tumor necrosis factor alpha (TNF-alpha) and receptor type I (TNFR1) in Abeta25-35-induced inflammatory reaction in SH-SYSY cell lines.

METHODThe 5 micromol . L-1 Abeta25-35 was used to treat SH-SY5Y cells for 24 hours, in order to establish the Alzheimer's disease (AD) model. Before modeling, berberine was given for pretreatment for 2 hours. The experiment included the normal control group, the AD model group, and indometacin low dose and high dose groups. Spectrophotometry was adopted to detect the activity of LDH. Meanwhile, the level of TNF-alpha was determined by ELISA, and the expression of TNFR1 genes was detected by RT-PCR.

RESULTCompared with the normal control group, the AD cell model group showed significant increase in LDH, TNF-alpha, and TNFR1 gene and protein expressions in the culture media. After intervention with berberine, the activity of LDH and TNF-alpha reduced in cell supernatant. The intervention with berberine could down-regulate TNFR1 gene and protein expressions, particularly 1, 10 x 10(-6) mol . L-l berberine showed a more notable effect in regulating TNFR1.

CONCLUSIONBerberine has the protective effect in Abeta-induced inflammatory injury in SH-SY5Y cells. Its mechanism may be related to the expression of its anti inflammatory factor TNF-alpha and its type I receptor TNFR1. Specifically, its regulation to TNFR1 shows dose dependence.

Amyloid beta-Peptides ; toxicity ; Berberine ; pharmacology ; Cell Line ; Humans ; Inflammation ; chemically induced ; metabolism ; Peptide Fragments ; toxicity ; Receptors, Interleukin-1 Type I ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

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

Amyloid beta (Abeta) neurotoxicity is believed to play a critical role in the pathogenesis of Alzheimer's disease (AD) mainly because of its deposition in AD brain and its neuronal toxicity. However, there have been discrepancies in Abeta-induced cytotoxicity studies, depending on the assay methods. Comparative analysis of Abeta42-induced in vitro cytotoxicity might be useful to elucidate the etiological role of Abeta in the pathogenesis of AD. In this study, MTT, CCK-8, calcein-AM/EthD-1 assays as well as thorough microscopic examinations were comparatively performed after Abeta42 treatment in a neuronal precursor cells (NT2) and a somatic cells (EcR293). Extensive formation of vacuoles was observed at the very early stage of Abeta42 treatment in both cells. Early observation of Abeta42 toxicity as seen in vacuole formation was also shown in MTT assay, but not in CCK-8 and calcein-AM/EthD-1 assays. In addition, Abeta42 treatment dramatically accelerated MTT formazan exocytosis, implying its effect on the extensive formation of cytoplasmic vacuoles. Abeta42 seems to cause indirect inhibition on the intracellular MTT reduction as well as vacuole formation and exocytosis enhancement. Following the acute cellular dysfunction induced by Abeta42, the prolonged treatment of micromolar concentration of Abeta42 resulted in slight inhibition on redox and esterase activity. The early Abeta42-induced vacuolated morphology and later chronic cytotoxic effect in neuronal cell might be linked to the chronic neurodegeneration caused by the accumulation of Abeta42 in AD patients' brain.
Amyloid beta-Protein/*toxicity ; Animals ; Cell Death/drug effects ; Cell Line ; Dose-Response Relationship, Drug ; Exocytosis/*drug effects ; Formazans ; Neurons/*drug effects/metabolism/*pathology ; Peptide Fragments/*toxicity ; Research Support, Non-U.S. Gov't ; Tetrazolium Salts ; Time Factors ; Vacuoles/*drug effects

OBJECTIVETo investigate the changes of p38MAPK expression in a rat model of Alzheimer disease (AD).

METHODSSeventy-two adult SD rats were randomized equally into 4 groups, and a single-dose injection of Abeta25-35 (dementia group), normal saline (saline group), SB203580 (inhibitor group), or DMSO (inhibitor control group) was administered into the lateral cerebral ventricle. Y-maze tast was performed to evaluate the behavioral changes of the rats after the injections, and on days 4, 7 and 14 after the injection, p38MAPK expression in the hippocampal CA1 area was measured by means of immunohistochemistry.

RESULTSOn days 7 and 14 following Abeta25-35 injection, the training times, error number and total reaction time were significantly higher in dementia group than in saline group (P<0.05), but all these indices were significantly lowered in the inhibitor group as compared with the dementia group (P<0.05). Immunohistochemistry revealed obvious p38 expression in the dementia group 4 days after Abeta25-35 injection, which increased significantly with the passage of time (P<0.01). The gray scale in the inhibitor group was significantly higher than that in the dementia group (P<0.01).

CONCLUSIONp38MAPK activation in the hippocampal CA1 area is an event that persists during the entire course of Abeta25-35-induced AD in rats, and the inhibitor SB203580 prevents p38MAPK expression and improves the learning and memory abilities of the rats.

Alzheimer Disease ; chemically induced ; enzymology ; metabolism ; Amyloid beta-Peptides ; administration & dosage ; toxicity ; Animals ; Hippocampus ; drug effects ; enzymology ; Immunohistochemistry ; Male ; Maze Learning ; drug effects ; Peptide Fragments ; administration & dosage ; toxicity ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; p38 Mitogen-Activated Protein Kinases ; biosynthesis

Whole-cell patch clamp recording was used to investigate the action of beta-amyloid peptide(1-40) (Abeta(1-40)) on high voltage-activated calcium channel current (I(HVA)) in acutely isolated hippocampal CA1 pyramidal neurons in rats and observe its modulation by ginkgolide B (GB). Drug was applied by extracellular bath or adding in the pipette solution, and its effect was determined by comparing the amplitude of I(HVA) before and after the drug application. Bath application of aggregated Abeta(1-40) at concentrations of 0.01~30 mumol/L increased the amplitude of I(HVA) in a dose-dependent manner by (5.43+/-3.01)% (n=8, P>0.05), (10.49+/-4.13) % (n=11, P>0.05), (40.69+/-8.01) % (n=16, P<0.01), (58.32+/-4.85) % (n=12, P<0.01), and (75.45+/-5.81) % (n=6, P<0.01), respectively, but had no effect on the I-V curve of I(HVA); fresh Abeta(1-40) almost had no effect on I(HVA) (n=5, P>0.05). L-type calcium channel antagonist nifedipine abolished the increase of I(HVA)by Abeta(1-40). The increase of I(HVA) by Abeta(1-40) (1.0 mumol/L) was enhanced to (66.19+/-5.74) % (P<0.05) by 8-Br-cAMP (membrane permeable analogue of cAMP) and to (73.21+/-6.90) % (P<0.05) by forskolin, an adenylyl cyclase (AC) agonist, and reduced to (20.08+/-2.18) % (P<0.05) by H-89, cyclic adenosine monophosphate (cAMP)-dependent protein kinase A (PKA) antagonist. GB effectively inhibited the increase of I(HVA) by Abeta(1-40). The results indicate that Abeta(1-40) leads to an intracellular calcium overload by increasing I(HVA) via AC-cAMP-PKA. This may be one of the mechanisms for its neurotoxicity. GB can prevent neurons from neurotoxicity by inhibiting abnormal calcium influx caused by Abeta(1-40).
Amyloid beta-Peptides ; toxicity ; Animals ; Animals, Newborn ; Calcium Channels ; drug effects ; Ginkgolides ; pharmacology ; Hippocampus ; cytology ; metabolism ; Lactones ; pharmacology ; Neurons ; drug effects ; metabolism ; Neuroprotective Agents ; pharmacology ; Patch-Clamp Techniques ; Peptide Fragments ; toxicity ; Rats ; Rats, Wistar