GCase protein levels and activity are reduced in sporadic AD brain tissues and Aβ_1–42 oligomer-treated primary neurons.

<p>(A and B) GCase expression was decreased in the hippocampal region of brains affected by Alzheimer’s disease (n = 6), as opposed to controls (n = 6). GCase expression levels were normalized to β-actin and quantified. (C) The GCase enzymatic activities were measured using lysosome-enriched fractions for the brains affected by Alzheimer’s disease and the controls (n = 6 per group). (D) Expression of <i>GBA1</i> gene was determined in AD hippocampal regions compared to the controls using real-time PCR. The β-actin mRNA was used as an internal reference control to normalize relative mRNA levels (n = 6 per group). (E) Oligomeric and monomeric Aβ_1–42 were identified by SDS-PAGE using anti-Aβ antibody (4G8). (F) Primary cortical neurons were incubated with 1 μM oligomeric Aβ_1–42 for 24 h at 10 days <i>in vitro</i>. The cell lysates were subjected to immunoblot using GCase and β-actin antibodies. (G) The expression level of GCase was quantified. Data are expressed as the mean ± SEM (Student’s t test, *<i>P</i> < 0.05, **<i>P</i> < 0.01).