scholarly journals Preparation of neuroprotective condensed 1,4-benzoxazepines by regio- and diastereoselective domino Knoevenagel–[1,5]-hydride shift cyclization reaction

2014 ◽  
Vol 10 ◽  
pp. 2594-2602 ◽  
Author(s):  
László Tóth ◽  
Yan Fu ◽  
Hai Yan Zhang ◽  
Attila Mándi ◽  
Katalin E Kövér ◽  
...  

Condensed O,N-heterocycles containing tetrahydro-1,4-benzoxazepine and tetrahydroquinoline moieties were prepared by a regio- and diastereoselective domino Knoevenagel–[1,5]-hydride shift cyclization reaction of a 4-aryl-2-phenyl-1,4-benzoxazepine derivative obtained from flavanone. The relative configuration of products were determined by the correlation of 3 J H,H coupling data with the geometry of major conformers accessed by DFT conformational analysis. Separated enantiomers of the products were characterized by HPLC-ECD data, which allowed their configurational assignment on the basis of TDDFT-ECD calculation of the solution conformers. Two compounds showed neuroprotective activities against hydrogen peroxide (H2O2) or β-amyloid25–35 (Aβ25–35)-induced cellular injuries in human neuroblastoma SH-SY5Y cells in the range of those of positive controls.

2010 ◽  
Vol 2010 ◽  
pp. 1-4 ◽  
Author(s):  
Jirapa Chetsawang ◽  
Piyarat Govitrapong ◽  
Banthit Chetsawang

It has been reported that overproduction of reactive oxygen species occurs after brain injury and mediates neuronal cells degeneration. In the present study, we examined the role of Ras signaling on hydrogen peroxide-induced neuronal cells degeneration in dopaminergic neuroblastoma SH-SY5Y cells. Hydrogen peroxide significantly reduced cell viability in SH-SY5Y cultured cells. An inhibitor of the enzyme that catalyzes the farnesylation of Ras proteins, FTI-277, and a competitive inhibitor of GTP-binding proteins, GDP-beta-S significantly decreased hydrogen peroxide-induced reduction in cell viability in SH-SY5Y cultured cells. The results of this study might indicate that a Ras-dependent signaling pathway plays a role in hydrogen peroxide-induced toxicity in neuronal cells.


1999 ◽  
Vol 155 (2) ◽  
pp. 252-259 ◽  
Author(s):  
C. Fabrizi ◽  
R. Businaro ◽  
G.M. Lauro ◽  
G. Starace ◽  
L. Fumagalli

PLoS ONE ◽  
2020 ◽  
Vol 15 (10) ◽  
pp. e0240022
Author(s):  
Wei-Ting Chen ◽  
Yu-Yi Kuo ◽  
Guan-Bo Lin ◽  
Chueh-Hsuan Lu ◽  
Hao-Ping Hsu ◽  
...  

Cells ◽  
2019 ◽  
Vol 8 (12) ◽  
pp. 1539 ◽  
Author(s):  
Bussiere ◽  
Oulès ◽  
Mary ◽  
Vaillant-Beuchot ◽  
Martin ◽  
...  

Dysregulation of the Endoplasmic Reticulum (ER) Ca2+ homeostasis and subsequent ER stress activation occur in Alzheimer Disease (AD). We studied the contribution of the human truncated isoform of the sarco-endoplasmic reticulum Ca2+ ATPase 1 (S1T) to AD. We examined S1T expression in human AD-affected brains and its functional consequences in cellular and transgenic mice AD models. S1T expression is increased in sporadic AD brains and correlates with amyloid β (Aβ) and ER stress chaperone protein levels. Increased S1T expression was also observed in human neuroblastoma cells expressing Swedish-mutated β-amyloid precursor protein (βAPP) or treated with Aβ oligomers. Lentiviral overexpression of S1T enhances in return the production of APP C-terminal fragments and Aβ through specific increases of β-secretase expression and activity, and triggers neuroinflammation. We describe a molecular interplay between S1T-dependent ER Ca2+ leak, ER stress and βAPP-derived fragments that could contribute to AD setting and/or progression.


2019 ◽  
Vol 59 ◽  
pp. 15-24
Author(s):  
Fatih Doğan Koca ◽  
Gökhan Ünal ◽  
Mehmet Gökhan Halici

Nanoparticles, smaller than 100 nm are synthesized by chemical and physical methods. Biological synthesis of nanoparticles is very popular in science recently. The aim of the study is green synthesis of zinc oxide nanoparticles (ZnO NPs) using the lichen extract (Ramalina fraxinea) and investigating the cytotoxic effects of ZnO NPs on human neuroblastoma cells (SHSY-5Y). Despite the widespread use of ZnO NPs, a limited number of studies have investigated the neurobiological effects of ZnO NP. Therefore, we tested the neurotoxic effect of green synthesized ZnO NPs administration and its neuroprotective effect against hydrogen peroxide-induced cell damage on SH-SY5Y human neuroblastoma cell line. The absorbance peak of the ZnO NPs was detected by UV–visible spectroscopy (UV-Vis) at 330 nm. The average diameter of ZnO NPs was measured as about 21 nm by Scanning Electron Microscope (SEM) and Field Emission Scanning Electron Microscope (FE-SEM) images. According to X-ray Diffraction (XRD) diagram, ZnO NPs were hexagonal in structure. The peaks observed in the Fourier Transform Infrared (FT-IR) test showed functional groups in the structure of the nanoparticles. According to our results, ZnO NPs may have beneficial effects at the low concentrations while neurotoxic effects at the higher doses in SH-SY5Y. In addition, we indicate that hydrogen peroxide-induced cell death could not reverse by ZnO NPs and its higher doses potentiated the neurodegenerative effect of hydrogen peroxide. In conclusion, here we report that ZnO NPs, widely used in various products, may have beneficial or harmful effects in a dose-dependent manner and play a role in neuropsychiatric disease, especially neurodegenerative diseases. This is the first study dealing with neurotoxicity on SHSY-5Y of Ramalina fraxinea extract based ZnO NPs.


2019 ◽  
Vol 44 (4) ◽  
pp. 884-896 ◽  
Author(s):  
Aline Lukasievicz Chenet ◽  
Adriane Ribeiro Duarte ◽  
Fhelipe Jolner Souza de Almeida ◽  
Cláudia Marlise Balbinotti Andrade ◽  
Marcos Roberto de Oliveira

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