• Molecules and Cells
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• 제20권2호
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• pp.256-262
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• 2005

The neuronal cytoskeleton is essential for establishment of neuronal polarity, but mechanisms controlling generation of polarity in the cytoskeleton are poorly understood. The nonreceptor tyrosine kinase, Fer, has been shown to bind to microtubules and to interact with several actin-regulatory proteins. Furthermore, Fer binds p120 catenin and has been shown to regulate cadherin function by modulating cadherin-${\beta}$-catenin interaction. Here we show involvement of Fer in neuronal polarization and neurite development. Fer is concentrated in growth cones together with cadherin, ${\beta}$-catenin, and cortactin in stage 2 hippocampal neurons. Inhibition of Fer-p120 catenin interaction with a cell-permeable inhibitory peptide (FerP) increases neurite branching. In addition, the peptide significantly delays conversion of one of several dendrites into an axon in early stage hippocampal neurons. FerP-treated growth cones also exhibit modified localization of the microtubule and actin cytoskeleton. Together, this indicates that the Fer-p120 interaction is required for normal neuronal polarization and neurite development.

• Molecules and Cells
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• 제43권6호
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• pp.581-589
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• 2020

Neurons have multiple dendrites and single axon. This neuronal polarity is gradually established during early processes of neuronal differentiation: generation of multiple neurites (stages 1-2); differentiation (stage 3) and maturation (stages 4-5) of an axon and dendrites. In this study, we demonstrated that the neuron-specific n-glycosylated protein NELL2 is important for neuronal polarization and axon growth using cultured rat embryonic hippocampal neurons. Endogenous NELL2 expression was gradually increased in parallel with the progression of developmental stages of hippocampal neurons, and overexpression of NELL2 stimulated neuronal polarization and axon growth. In line with these results, knockdown of NELL2 expression resulted in deterioration of neuronal development, including inhibition of neuronal development progression, decreased axon growth and increased axon branching. Inhibitor against extracellular signal-regulated kinase (ERK) dramatically inhibited NELL2-induced progression of neuronal development and axon growth. These results suggest that NELL2 is an important regulator for the morphological development for neuronal polarization and axon growth.

• Natural Product Sciences
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• 제15권3호
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• pp.162-166
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• 2009

Oxczaasssaidative stress plays an important role in neuronal cell death, which is associated with neurodegenerative conditions such as Alzheimer's and Parkinson's disease. This study evaluated the neuroprotective effect of Euryale ferox (EF) extracts against glutamate-induced cytotoxicity in hybridoma N18-RE-105 cells. Specifically, neuroprotective effects of methanol and ethanol extracts were evaluated by the MTT reduction assay. The ethanol extracts of EF displayed dose dependent protection against neuronal cell death induced by 20 mM of glutamate. Furthermore, the ethanol extracts of EF was sequentially fractionated with hexane, diethyl ether, ethyl acetate, and water layer according to degree of polarity. The hexane fractions exhibited neuroprotective effect against glutamate-stressed N18-RE-105 cells. Overall, results suggest that EF extracts can potentially be used as chemotherapeutic agents against neuronal diseases.

• Archives of Pharmacal Research
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• 제14권4호
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• pp.325-329
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• 1991

Effects of Lycii Fructus on primary cultured chicken embryonic brain cells were studied by microscopic observation, determination of the activity of pyruvate dehydrogenase complex (PDHC), and syntheses of protein, RNA and DNA. The brain cells were prepared from the brains or 10-day-old chicken embryos and cultured with a deficient medium. The activity of PDHC in the brain cells cultured with a deficient medium was increased to 1.8 times by the addition of $30\;{\mu}g/ml$ of the total methanol extract of Lycii Fructus. To seek the active fraction, total methanol extract was further fractionated by the polarity. The survival rate of neuronal cells was significantly increased by the addition of $100\;{\mu}g/ml$ of the buthanol or aqueous fraction. At this concentration, the significant increase of the syntheses of protein and RNA, but not of DNA, indicates that the fractions may act on the neuronal cells which are known to be non-dividing cells.

• 생명과학회지
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• 제19권7호
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• pp.963-967
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• 2009

본 연구에서는 glutamate로 유도된 세포독성으로부터 신경세포를 보호하는 상백피(Morus alba) 추출물의 활성을 확인하기 위하여 N18-RE-105 세포주를 이용하여 MTT reduction assay, LDH release assay 및 광학 현미경을 이용하여 형태학적인 변화를 관찰하였다. 그 결과, 상백피 methanol 추출물에서 농도 의존적으로 신경세포 보호효과가 나타났으며, 50 본 연구에서는 glutamate 로 유도된 세포독성으로부터 신경세포를 보호하는 상백피 (Morus alba) 추출물의 활성을 확인하기 위하여 NI8-RE-I05 세포주를 이용하여 MTT reduction assay, LDH release assay 및 광학 현 미 경 을 이 용하여 형태학적인 변화를 관찰하였다. 그 결과y 상백피 methanol 추출물에서 농도 의존적으로 신경세포 보호효과가 나타났으며, 50 ${\mu}g$/ml 농도에서는 80% 이상의 세포생존율을 확인할수 있었다. 이 결과는 N18-RE-105 세포주의 LDH release assay와 형태학적 변화에서도 일치하는 결과를 확인하였다. 가장 높은 활성을 보인 상백피 methanol 추출물을 hexane, diethyl ether, ethyl acetate, water 층으로 분획하여 각 각 1, 5, 10 ${\mu}g$/ml 농도로 처리 시 hexane 층에서 48.0%, 65.6%, 71.5%로 가장 높은 신경세포 보호효과를 확인할 수 있었다. 따라서 상백피 추출물은 glutamate 에 의한 세포독성으로부터 신경세포 손상을 억제하며 신경세포를 보호하는 효과가 있다는 것을 알 수 있었다.

• 생명과학회지
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• 제20권2호
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• pp.253-259
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• 2010

본 연구는 땅콩나물 추출물이 glutamate가 유도하는 세포독성으로부터 신경세포를 보호하는 효과를 확인하였다. 땅콩나물을 부위별로 전체, 머리, 줄기 부분으로 나누어 methanol로 처리하여 얻어진 각각의 추출물 WME, HME 그리고 SME를 이용하여 glutamate에 의하여 유도된 세포독성에 대한 신경세포보호효과를 관찰하였다. 기지의 신경세포 N18-RE-105 세포주를 이용하여 MTT reduction assay, LDH release assay, 형태학적인 변화 및 apoptosis를 관찰한 결과로부터 HME에서 효율적인 신경세포보호효과를 보였다. 다음으로 HME를 이용하여 hexane, diethyl ether, ethyl acetate, water 층으로 분획하여 신경세포 보호 효과를 확인한 결과, diethyl ether 층에서 가장 높은 활성을 확인할 수 있었다. 그리고 HME의 apoptosis 억제 효과를 확인하기 위하여 flow cytometric analysis를 실시한 결과에서 glutamate 만을 처리하였을 경우 sub-G1기 세포가 58.5%의 확인되었으나 HME를 100 mg/ml 동시 처리하였을 때에는 sub-G1 세포가 9.1%로 감소하여 높은 apoptosis 억제 효과를 확인할 수 있었다. 이상의 결과로부터 땅콩나물 머리 부분 methanol 추출물에는 glutamate에 의한 세포독성으로부터 신경세포를 보호하는 효과가 있다는 것을 알 수 있었다.