[Neuroprotective effect of ginsenoside Re on drosophila model of Parkinson's disease].

This study aims to explore the neuroprotective mechanism of ginsenoside Re(GS-Re) on drosophila model of Parkinson's disease(PD) induced by rotenone(Rot). To be specific, Rot was used to induce PD in drosophilas. Then the drosophilas were grouped and respectively treated(GS-Re: 0.1, 0.4, 1.6 mmol·L~(-1); L-dopa: 80 µmol·L~(-1)). Life span and crawling ability of drosophilas were determined. The brain antioxidant activity [content of catalase(CAT), malondialdehyde(MDA), reactive oxygen species(ROS), superoxide dismutase(SOD)], dopamine(DA) content, and mitochondrial function [content of adenosine triphosphate(ATP), NADH:ubiquinone oxidoreductase subunit B8(NDUFB8) Ⅰ activity, succinate dehydrogenase complex, subunit B(SDHB) Ⅱ activity] were detected by enzyme-linked immunosorbent assay(ELISA). The number of DA neurons in the brains of drosophilas was measured with the immunofluorescence method. The levels of NDUFB8 Ⅰ, SDHB Ⅱ, cytochrome C(Cyt C), nuclear factor-E2-related factor 2(Nrf2), heme oxygenase-1(HO-1), B-cell lymphoma/leukemia 2(Bcl-2)/Bcl-2-assaciated X protein(Bax), and cleaved caspase-3/caspase-3 in the brain were detected by Western blot. The results showed that model group [475 µmol·L~(-1) Rot(IC_(50))] demonstrated significantly low survival rate, obvious dyskinesia, small number of neurons and low DA content in the brain, high ROS level and MDA content, low content of SOD and CAT, significantly low ATP content, NDUFB8 Ⅰ activity, and SDHB Ⅱ activity, significantly low expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax, large amount of Cyt C released from mitochondria to cytoplasm, low nuclear transfer of Nrf2, and significantly high expression of cleaved caspase-3/caspase-3 compared with the control group. GS-Re(0.1, 0.4, and 1.6 mmol·L~(-1)) significantly improved the survival rate of PD drosophilas, alleviated the dyskinesia, increased DA content, reduced the loss of DA neurons, ROS level, and MDA content in brain, improved content of SOD and CAT and antioxidant activity in brain, maintained mitochondrial homeostasis(significantly increased ATP content and activity of NDUFB8 Ⅰ and SDHB Ⅱ, significantly up-regulated expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax), significantly reduced the expression of Cyt C, increased the nuclear transfer of Nrf2, and down-regulated the expression of cleaved caspase-3/caspase-3. In conclusion, GS-Re can significantly relieve the Rot-induced cerebral neurotoxicity in drosophilas. The mechanism may be that GS-Re activates Keap1-Nrf2-ARE signaling pathway by maintaining mitochondrial homeostasis, improves antioxidant capacity of brain neurons, then inhibits mitochondria-mediated caspase-3 signaling pathway, and the apoptosis of neuronal cells, thereby exerting the neuroprotective effect.

Neuroprotective effect of ginsenoside Re on drosophila model of Parkinson's disease / 中国中药杂志

This study aims to explore the neuroprotective mechanism of ginsenoside Re(GS-Re) on drosophila model of Parkinson's disease(PD) induced by rotenone(Rot). To be specific, Rot was used to induce PD in drosophilas. Then the drosophilas were grouped and respectively treated(GS-Re: 0.1, 0.4, 1.6 mmol·L~(-1); L-dopa: 80 μmol·L~(-1)). Life span and crawling ability of drosophilas were determined. The brain antioxidant activity [content of catalase(CAT), malondialdehyde(MDA), reactive oxygen species(ROS), superoxide dismutase(SOD)], dopamine(DA) content, and mitochondrial function [content of adenosine triphosphate(ATP), NADH:ubiquinone oxidoreductase subunit B8(NDUFB8) Ⅰ activity, succinate dehydrogenase complex, subunit B(SDHB) Ⅱ activity] were detected by enzyme-linked immunosorbent assay(ELISA). The number of DA neurons in the brains of drosophilas was measured with the immunofluorescence method. The levels of NDUFB8 Ⅰ, SDHB Ⅱ, cytochrome C(Cyt C), nuclear factor-E2-related factor 2(Nrf2), heme oxygenase-1(HO-1), B-cell lymphoma/leukemia 2(Bcl-2)/Bcl-2-assaciated X protein(Bax), and cleaved caspase-3/caspase-3 in the brain were detected by Western blot. The results showed that model group [475 μmol·L~(-1) Rot(IC_(50))] demonstrated significantly low survival rate, obvious dyskinesia, small number of neurons and low DA content in the brain, high ROS level and MDA content, low content of SOD and CAT, significantly low ATP content, NDUFB8 Ⅰ activity, and SDHB Ⅱ activity, significantly low expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax, large amount of Cyt C released from mitochondria to cytoplasm, low nuclear transfer of Nrf2, and significantly high expression of cleaved caspase-3/caspase-3 compared with the control group. GS-Re(0.1, 0.4, and 1.6 mmol·L~(-1)) significantly improved the survival rate of PD drosophilas, alleviated the dyskinesia, increased DA content, reduced the loss of DA neurons, ROS level, and MDA content in brain, improved content of SOD and CAT and antioxidant activity in brain, maintained mitochondrial homeostasis(significantly increased ATP content and activity of NDUFB8 Ⅰ and SDHB Ⅱ, significantly up-regulated expression of NDUFB8 Ⅰ, SDHB Ⅱ, and Bcl-2/Bax), significantly reduced the expression of Cyt C, increased the nuclear transfer of Nrf2, and down-regulated the expression of cleaved caspase-3/caspase-3. In conclusion, GS-Re can significantly relieve the Rot-induced cerebral neurotoxicity in drosophilas. The mechanism may be that GS-Re activates Keap1-Nrf2-ARE signaling pathway by maintaining mitochondrial homeostasis, improves antioxidant capacity of brain neurons, then inhibits mitochondria-mediated caspase-3 signaling pathway, and the apoptosis of neuronal cells, thereby exerting the neuroprotective effect.

Prolonged activation of cytomegalovirus early gene e1-promoter exclusively in neurons during infection of the developing cerebrum.

The brain is the major target of congenital cytomegalovirus (CMV) infection. It is possible that neuron disorder in the developing brain is a critical factor in the development of neuropsychiatric diseases in later life. Previous studies using mouse model of murine CMV (MCMV) infection demonstrated that the viral early antigen (E1 as a product of e1 gene) persists in the postnatal neurons of the hippocampus (HP) and cerebral cortex (CX) after the disappearance of lytic infection from non-neuronal cells in the periventricular (PV) region. Furthermore, neuron-specific activation of the MCMV-e1-promoter (e1-pro) was found in the cerebrum of transgenic mice carrying the e1-pro-lacZ reporter construct. In this study, in order to elucidate the mechanisms of e1-pro activation in cerebral neurons during actual MCMV infection, we have generated the recombinant MCMV (rMCMV) carrying long e1-pro1373- or short e1-pro448-EGFP reporter constructs. The length of the former, 1373 nucleotides (nt), is similar to that of transgenic mice. rMCMVs and wild type MCMV did not significantly differed in terms of viral replication or E1 expression. rMCMV-infected mouse embryonic fibroblasts showed lytic infection and activation of both promoters, while virus-infected cerebral neurons in primary neuronal cultures demonstrated the non-lytic and persistent infection as well as the activation of e1-pro-1373, but not -448. In the rMCMV-infected postnatal cerebrum, lytic infection and the activation of both promoters were found in non-neuronal cells of the PV region until postnatal 8 days (P8), but these disappeared at P12, while the activation of e1-pro-1373, but not -448 appeared in HP and CX neurons at P8 and were prolonged exclusively in these neurons at P12, with preservation of the neuronal morphology. Therefore, e1-pro-448 is sufficient to activate E1 expression in non-neuronal cells, however, the upstream sequence from nt -449 to -1373 in e1-pro-1373 is supposed to work as an enhancer necessary for the neuron-specific activation of e1-pro, particularly around the second postnatal week. This unique activation of e1-pro in developing cerebral neurons may be an important factor in the neurodevelopmental disorders induced by congenital CMV infection.

Effect of IL-6、IL-1?、TNF? on the Growth of Human Fetal Cerebral Neurons in vitro / 中国免疫学杂志

Objective:To study the effects of Il 6?IL 1??TNF? on the growth and development of cultured human fetal cerebral neurons.Methods:Established the model of primary culture of human fetal cerbral neurons in SFFD,by morphological observation and MTT assay.Results:IL 6 and IL 1? both promote the survival of neurons and IL 6 also promote the outgrowth of neuritis and differentiation of neurons in culture.TNF ? continuously inhibit the survival of neurons.Conclusion:IL 6?IL 1??TNF? can effect the development of cultured neurons.IL 6 and IL 1? both may effect as neurotrophic factor in the survival?growth and development by indirect mechanism.TNF? directly show neurotoxin effect in culture.

IL-6、IL-1? and TNF? induce the expression of c-fos and c -jun in human fetal cere-bral neurons / 中国免疫学杂志

Objective:To study the effects of IL 6、IL 1? and TNF? on the expression of c fos and c jun,which may provide the foundation for a further study in clinic.Methods:Used the a model of primary culture of human fetal cerebral neurons in serum free medium,by DNA RNA dot blot hybrdization.Results:The expression of c fos and c jun was increased between 15 min to 30 min after stimulation,reached a maximum at 1 h and declined over the subsequent 1 h.Conclusion:IL 6、IL 1? and TNF ? have induce the expression of c fos and c jun during development of human fetal cerebral neurons in vitro at the level of transcription.

The Protective Effect of Vitamin E and Desferrioxamine on Cultured Cerebral Neurons of Neonatal Mouse Damaged by Ischemic Condition

PURPOSE: Perinatal asphyxia is an important cause of neurologic morbidity. Experiments in animal models of hypoxic-ischemic brain injury demonstrate that brain damage starts during hypoxia-ischemia. In order to evaluate the ischemic condition-induced neurotoxic effect in view of oxi-dative stress, we examined the cytotoxic effect in cultured cerebral neurons of neonatal mouse. METHODS: Dissociated cell cultures were prepared from cerebrum of neonatal mouse. Tissues were diced into small pieces and were incubated in phosphate buffered saline at 37degrees C. Isolated cells were resuspended in the medium and plated in poly-L-lysine coated 96 well multichambers at a cell density of 5x104cells/well. Cells were grown in a 5% CO2/95% air atmosphere at 37degrees C. Cytotoxic effects were examined in the cultured cerebral neurons with time interval in the ischemic condition with a 95% nitrogen/5% CO2. And the protective effect of vitamin E and desferrioxamine as an antioxidant was examined by MTT assay and neurofilament enzymeimmunoassay(EIA). Microscopic examinations were also done. RESULTS: Ischemic condition markedly decreased the cell viability in a time-dependent manner in cultured cerebral neurons. MTT50 value was estimated at 10 minutes, when cerebral neurons were incubated for various time intervals in ischemic condition. Under light microscopy, the number of cells and neurites were decreased when cerebral neurons were cultured for 10 minutes in the ischemic condition. Vitamin E was an effective antioxidant in blocking ischemic condition-induced neurotoxicity, while desferrioxamine was not in these cultures. CONCLUSION: It is suggested that ischemic conditions are neurotoxic and selective antioxidant such as vitamin E is effective in protecting against the neurotoxicity induced by ischemic condition in cultured cerebral neurons of neonatal mouse.

Antioxidant Effect of Allopurinol on Oxygen Radical-Induced Toxicity in Cultured Mouse Cerebral Neurons / 체질인류학회지

In order to elucidate the neurotoxic effect of oxygen radicals on cultured mouse cerebral neurons, the neurotoxicity induced by xanthine oxidase (XO) and hypoxanthine (HX), was evaluated by MTT assay. The neuroprotective effect of allopurinol against oxidant -mediated neurotoxicity was also examined in these cultures by MTT assay and neurofilament enzymeimmunoassay (EIA) with light microscopy. The results were as follows: 1. Oxygen radicals induced degenerative changs such as the decrease of cell number and the loss of neurites in cultured mouse cerebral neurons. 2. The value of midcytotoxicity value (MTT50) of oxygen radicals was estimated at a concentration of 20 mU/ml XO and 0.1 mM HX for 4 hours in these cultures. 3. Cell viability of cultured mouse cerebral neurons was significantly decreased by XO/HX in a dose -and time -dependent manners. 4. Allopurinol was very effective in blocking the neurotoxicity induced by XO/HX at a concentration of 30 microM as determined by MTT assay and neurofilament enzymeimmunoas-say. From the above results, it is suggested that oxygen radicals show neurotoxicity, and the selective antioxidant such as allopurinol are very effective in blocking oxidant -mediated neurotoxicity on cultured mouse cerebral neurons.