Fig. 5.

Effects of UCP2 over-expression on insulin secretion and cell death in islets exposed to glucotoxic conditions. (A) Glucose stimulated insulin secretion from WT and RIP-UCP2 islets was tested at the end of the 7-day culture period at either standard glucose (11 mM Glc) or glucotoxic condition (30 mM Glc). Both WT and RIP-UCP2 islets were pre-incubated at 2.8 mM glucose for 1hr and then insulin release was measured from islets kept at 2.8 mM glucose (Low) or stimulated by 22.8 mM glucose (Stim) for 1hr. *p < 0.05 versus corresponding Low of the same genotype and the same culture condition, #p < 0.05 versus corresponding WT in the same culture condition, &p < 0.05 versus corresponding secretion assay condition from the 11 mM Glc culture islets. (B) Islet cell apoptosis was determined in cell lysates by quantification of cytoplasmic nucleosomes in WT and RIP-UCP2 islets collected at the end of the 7-day culture period. **p < 0.01, *p < 0.05 versus corresponding genotype of 11 mM Glc; #p < 0.05 versus WT of 30 mM Glc.