[Influence of beta-amyloid peptide on cell membrane lipids and cholinergic receptors in human neuroblastoma SH-SY5Y cells].
OBJECTIVE
To study the effects of beta-amyloid peptide (Abeta) on cell membrane lipids and cholinergic receptors of human neuroblastoma cells.


METHODS
Human SH-SY5Y neuroblastoma cells were treated with different concentrations of Abeta(1-42) with and without pretreatment of vitamin E. MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide] reduction, lipid peroxidation, protein oxidation and phospholipids were measured by spectrophotometry. Levels of cholesterol and unbiquinone were determined by high-performance liquid chromatography (HPLC). The numbers of cholinergic receptor binding sites were determined by receptor binding assay and the protein levels of nicotinic receptor alpha3 and alpha7 subunits were studied by Western blotting.


RESULTS
SH-SY5Y cells showed decreased reduction rates of MMT and phospholipids, and increased lipid peroxidation and protein oxidation after exposure to Abeta (0.1 micromol/L) as compared to the control. The number of cholinergic receptor binding sites, the protein level of nicotinic receptor alpha3 and alpha7 subunits and the content of ubiquinone decreased in cells treated with high dose of Abeta (1 micromol/L). Although the level of cholesterol was not changed in any way, vitamin E partially prevented the neurotoxic effects of Abeta.


CONCLUSIONS
beta-amyloid peptide reduces the level of cell membrane lipids and cholinergic receptors in human SH-SY5Y neuroblastoma cells, likely through the induction of an enhanced oxidative stress.
Qi
Xiao-lan
XL
Department of Pathology, Guiyang Medical College, Guiyang 550004, China.
Shan
Ke-ren
KR
Xiao
Yan
Y
Liu
Ru-yu
RY
Gu
Ran
R
Guan
Zhi-zhong
ZZ
D016229:Amyloid beta-Peptides / Q000008:administration & dosage / Q000378:metabolism / Q000633:toxicity*; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism; D002784:Cholesterol / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D006801:Humans; D015227:Lipid Peroxidation / Q000187:drug effects; D008315:Malondialdehyde / Q000378:metabolism; D008563:Membrane Lipids / Q000378:metabolism*; D009447:Neuroblastoma / Q000378:metabolism* / Q000473:pathology; D018384:Oxidative Stress / Q000187:drug effects; D010446:Peptide Fragments / Q000008:administration & dosage / Q000378:metabolism / Q000633:toxicity*; D010743:Phospholipids / Q000378:metabolism; D011978:Receptors, Nicotinic / Q000378:metabolism*; D014451:Ubiquinone / Q000378:metabolism; D014810:Vitamin E / Q000378:metabolism / Q000494:pharmacology
D016229:Amyloid beta-Peptides; D002784:Cholesterol; D008315:Malondialdehyde; D008563:Membrane Lipids; D010446:Peptide Fragments; D010743:Phospholipids; D011978:Receptors, Nicotinic; D014451:Ubiquinone; D014810:Vitamin E; C075222:amyloid beta-protein (1-42)