Lipotoxic Stress Induces Pancreatic β-Cell Apoptosis through Modulation of Bcl-2 Proteins by the Ubiquitin-Proteasome System

Figure 3

UPS inactivation induces ER stress in β-cells. ((a)–(f)) MIN6 cells were treated with 0.5 mM palmitate ((a), (c), and (e)) or 10 μM MG132 ((b), (d), and (f)) and ER stress markers (ATF4, Chop, and Bip) measured as indicated. RNA was isolated using NucleoSpin RNA XS kit and cDNA was made with a High Capacity cDNA Reverse Transcriptase Kit. mRNA was analysed via real-time PCR analysis and standardised to β-actin internal control levels. ((g)-(h)) MIN6 cells were treated with 0.5 mM palmitate (g) or 10 μM MG132 (h) as indicated, and levels of Chop protein expression were measured by Western blot. Band intensities were quantified and standardised to β-actin loading control. Results are the means ± SEM of 3–5 independent experiments. , , and .

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