Figure 2. Nampt and NMN have no direct effects on beta-cell survival in human islets.

(A,B) Human pancreatic islets were cultured in suspension with the mixture of 22.2 mM glucose/0.5 mM palmitate or 2 ng/ml IL-1β/1000 IU IFN-γ in the absence (con) or presence of NMN (100 µM) or Nampt (2.5 ng/ml) for 72 h. Apoptosis was analysed in paraffin embedded islet sections by the TUNEL assay (red nuclei, white arrows) and counter-stained in green for insulin (B). Results are means ±SEM of the %TUNEL-positive beta-cells (the average number of beta-cells counted were 1456±277 for each treatment group in each experiment) of three different experiments from three different organ donors. B: shows representative staining pictures. *p<0.05 compared to vehicle treated control.