Nrf2 Activation Protects Mouse Beta Cells from Glucolipotoxicity by Restoring Mitochondrial Function and Physiological Redox Balance

Figure 7

Nrf2 activation influences cell viability of islet cells. (a) Culturing mouse islet cells in standard medium with or without oltipraz (10 μmol/L) for approximately 16 h did not affect the fraction of apoptotic cells. (b) After the 16 h culture period, cells were stressed by 25 or 100 μmol/L H₂O₂ in the continued presence of oltipraz for 2 h. Apoptosis tends to be reduced by oltipraz in those cells exposed to the lower H₂O₂ concentration (left diagram), but not when H₂O₂-induced cell damage was high (right diagram). Note that scaling is different to provide adequate resolution. (c) After the 16 h culture period, medium was exchanged and culture was continued in the presence of 33 mmol/L glucose and 10 μmol/L T0901317 in the presence or absence of oltipraz for 7 days. Nrf2 activation markedly reduced the fraction of apoptotic cells. Images of one representative experiment are shown on the right. The upper images illustrate nuclear staining. Arrows indicate TUNEL-positive cells shown in the lower traces. Numbers in bars indicate the number of independent preparations. .

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