22R-Hydroxycholesterol induces differentiation of human NT2 precursor (Ntera2/D1 teratocarcinoma) cells.
Recently, we have shown that 22R-hydroxycholesterol, a steroid intermediate in the pathway of pregnenolone formation from cholesterol, is present at lower levels in Alzheimer's disease (AD) hippocampus and frontal cortex tissue specimens than in age-matched controls, and that this substance protects against cell death induced by amyloid beta-peptide in both rat sympathetic nerve pheochromocytoma (PC12) and differentiated human Ntera2/D1 teratocarcinoma neurons. Herein we report that 22R-hydroxycholesterol inhibits the proliferation of human Ntera2/D1 teratocarcinoma precursor cells (NT2) and induces these cells to differentiate into "neuron-like" or "astrocyte-like" cells. 22R-Hydroxycholesterol-induced differentiation of NT2 cells is associated with increases in the expression of neurofilament protein NF200, the cytoskeletal proteins microtubule-associated protein type II (MAP2) a and MAP2b, glial fibrillary acidic protein (GFAP) and glial cell line-derived neurotrophic factor receptor-alpha 2 (GFRalpha2). These effects of 22R-hydroxycholesterol are considered to be stereospecific because its enantiomer 22S-hydroxycholesterol and other steroids failed to induce differentiation of NT2 cells. 22R-Hydroxycholesterol was found to lack specific binding for numerous receptors, including all steroid receptors tested. However, using a cholesterol protein binding blot assay we demonstrated the presence of a 22R-hydroxycholesterol-binding protein in NT2 cells distinct from the human oxysterol receptors liver X receptor LXRalpha and beta.
Yao
Z-X
ZX
Department of Biochemistry and Molecular and Cellular Biology, Georgetown University Medical Center, Washington, DC 20057, USA.
Han
Z
Z
Xu
J
J
Greeson
J
J
Lecanu
L
L
Papadopoulos
V
V
D001973:Bromodeoxyuridine; D016923:Cell Death / Q000187:drug effects; D002454:Cell Differentiation / Q000187:drug effects*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002784:Cholesterol / Q000378:metabolism / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry / Q000379:methods; D005786:Gene Expression Regulation / Q000187:drug effects; D020662:Guanine Nucleotide Exchange Factors / Q000378:metabolism; D006801:Humans; D006888:Hydroxycholesterols / Q000378:metabolism / Q000494:pharmacology*; D007770:L-Lactate Dehydrogenase; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000187:drug effects / Q000502:physiology*; D018243:Teratocarcinoma; D013778:Tetrazolium Salts; D013844:Thiazoles; D013997:Time Factors; D014316:Tritium / Q000378:metabolism; D020663:ras Guanine Nucleotide Exchange Factors
D020662:Guanine Nucleotide Exchange Factors; D006888:Hydroxycholesterols; D009419:Nerve Tissue Proteins; C417242:RAPGEF5 protein, human; D013778:Tetrazolium Salts; D013844:Thiazoles; D020663:ras Guanine Nucleotide Exchange Factors; D014316:Tritium; C003585:22-hydroxycholesterol; D002784:Cholesterol; D007770:L-Lactate Dehydrogenase; C022616:thiazolyl blue; D001973:Bromodeoxyuridine