An apolipoprotein E4 fragment affects matrix metalloproteinase 9, tissue inhibitor of metalloproteinase 1 and cytokine levels in brain cell lines

• Published in: Neuroscience Vol. 210; pp. 21 - 32
• Main Authors: Dafnis, I, Tzinia, A.K, Tsilibary, E.C, Zannis, V.I, Chroni, A
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Ltd 17.05.2012; Elsevier
• Subjects: Alzheimer disease; Alzheimer Disease - metabolism; Alzheimer's disease; apolipoprotein E; Apolipoprotein E4; Apolipoprotein E4 - metabolism; Apolipoprotein E4 - pharmacology; apolipoprotein E4 fragments; Astrocytes - drug effects; Astrocytes - metabolism; Astrocytoma; Biological and medical sciences; Blotting, Western; Brain; Brain - drug effects; Brain - metabolism; Cell Line, Tumor; Chromium; Cytokines; Cytokines - drug effects; Cytokines - metabolism; Degenerative and inherited degenerative diseases of the nervous system. Leukodystrophies. Prion diseases; Extracellular levels; Fundamental and applied biological sciences. Psychology; Gelatinase B; Gene expression; Humans; Inflammation; Inflammation - metabolism; Interleukin 1; Interleukin 10; Matrix metalloproteinase; matrix metalloproteinase 9; Matrix Metalloproteinase 9 - drug effects; Matrix Metalloproteinase 9 - metabolism; Medical sciences; Nervous system; Neurodegenerative diseases; neuroinflammation; Neurology; Neurons - drug effects; Neurons - metabolism; Peptide Fragments - metabolism; Peptide Fragments - pharmacology; Polymerase chain reaction; Proteolysis; Real-Time Polymerase Chain Reaction; Risk factors; Tissue inhibitor of metalloproteinase 1; Tissue Inhibitor of Metalloproteinase-1 - drug effects; Tissue Inhibitor of Metalloproteinase-1 - metabolism; Transfection; Tumor necrosis factor- alpha; Vertebrates: nervous system and sense organs; Western blotting; threshold cycles; TNFα; Alzheimer disease; apolipoprotein E4 fragments; HRP; apoE; phenylmethylsulfonyl fluoride; interleukin-10; tissue inhibitor of metalloproteinase 1; interleukin-1β; Aβ; neuroinflammation; FBS; CSF; ethylenediaminetetraacetic acid; horseradish peroxidase; cytokines; TIMP1; Eagle; WT; quantitative real-time polymerase chain reaction; PBS; AD; apoE4-185; apoE4-165; qRT-PCR; apoE4[Δ(186–299)]; β-amyloid peptide; EDTA; IL-1β; apoE4[Δ(166–299)]; MMP9; IL-10; tumor-necrosis factor α; CT; fetal bovine serum; PMSF; matrix metalloproteinase 9; phosphate buffered saline; cerebrospinal fluid; apolipoprotein E; wild type; Minimum Essential Medium; GAPDH; glyceraldehyde 3-phosphate dehydrogenase; Nervous system diseases; Enzyme; Central nervous system; Cytokine; Metalloendopeptidases; Neuroinflammation; Gelatinase B; Cerebral disorder; Encephalon; Peptidases; Cell line; Apolipoprotein E; Central nervous system disease; Hydrolases; matrix metalloproteinase 9, neuroinflammation; Degenerative disease; Metalloproteinase
• ISSN: 0306-4522; 1873-7544
• DOI: 10.1016/j.neuroscience.2012.03.013

Abstract Apolipoprotein (apo) E4 isoform, a major risk factor for Alzheimer disease (AD), is more susceptible to proteolysis than apoE2 and apoE3 isoforms. ApoE4 fragments have been found in AD patients' brain. In the present study, we examined the effect of full-length apoE4 and apoE4 fragments apoE4[Δ(186–299)] and apoE4[Δ(166–299)] on inflammation in human neuroblastoma SK-N-SH and human astrocytoma SW-1783 cells. Western blot and zymography analysis showed that treatment of SK-N-SH cells with apoE4[Δ(186–299)], but not full-length apoE4 or the shorter apoE4[Δ(166–299)] fragment, leads to increased extracellular levels of matrix metalloproteinase 9 (MMP9) and tissue inhibitor of metalloproteinase 1 (TIMP1). Real-time PCR showed that interleukin (IL)-1β gene expression is also increased in SK-N-SH cells treated with apoE4[Δ(186–299)]. Treatment of SK-N-SH cells with IL-1β leads to increased MMP9 and TIMP1 extracellular levels, suggesting that the induction of IL-1β may be the mechanism by which apoE4[Δ(186–299)] regulates MMP9 and TIMP1 levels in these cells. In contrast to SK-N-SH cells, treatment of SW-1783 cells with apoE4[Δ(186–299)], and to a lesser extent with apoE4, leads to increased TIMP1 extracellular levels without affecting MMP9 levels. Additionally, apoE4[Δ(186–299)] leads to decreased IL-10 gene expression in SK-N-SH cells, whereas both apoE4 and apoE4[Δ(186–299)] lead to decreased TNFα gene expression without affecting IL-1β and IL-10 gene expression in SW-1783 cells. Overall, our findings indicate that a specific apoE4 fragment (apoE4[Δ(186–299)]), with molecular mass similar that of apoE4 fragments detected in AD patients' brain, can influence the level of inflammatory molecules in brain cell lines. It is possible that these phenomena contribute to AD pathogenesis.