SFM and chromatin-modifying reagents enhance reprogramming of exocrine pancreatic MSCs toward glucagon-producing cells. A: Representative phase contrast images of passaged exocrine pancreatic fractions cultured in serum-containing medium (SCM)
or in SFM. Scale bar = 50 µm. B: Passaged exocrine pancreatic cells were cultured in SCM or SFM and transduced with adenoviruses expressing the 4TFs. After
24 h, 1 nmol/L betacellulin, 10 nmol/L exendin-4, and 10 mmol/L nicotinamide (BEN) were added to both SCM and SFM cultures.
After 7 days, the cells were harvested and QRT-PCR was performed. The data are expressed relative to glyceraldehyde 3-phosphate
dehydrogenase and presented as mean ± SEM (n = 3). *P < 0.05, **P < 0.01, and ***P < 0.001. C: Passaged exocrine pancreatic cells were cultured in SFM supplemented with 1 μmol/L 5-Aza-2′deoxycytidine (A) and/or 1 mmol/L
sodium butyrate (Bu), transduced with adenoviruses (4TF), and treated with BEN as indicated. QRT-PCR was performed and the
data were expressed relative to glyceraldehyde 3-phosphate dehydrogenase and presented as mean ± SEM (n = 3). ***P < 0.001 relative to nontreated samples (N/A). D: Glucagon secretion in culture medium of N/A or reprogrammed (A + Bu + 4TFs + BEN) exocrine cells in the presence of basal
(2.5 mmol/L) or after stimulation for 1 h with high (20 mmol/L) glucose. Glucagon levels were measured by ELISA and data represent
the mean ± SEM (n = 3). *P < 0.05. E: Glucagon and C-peptide immunofluorescent staining in exocrine cells treated with 4TFs and BEN in the presence of 5-Aza-2′deoxycytidine
and sodium butyrate. Scale bar = 20 µm. GLC, glucagon; INS, insulin; SST, somatostatin.