Figure 5.

Loperamide counters FoxO inhibition in different model systems.A. Overview of C. elegans development in favorable or unfavorable environmental conditions. B. Effects of FoxOi and loperamide treatment on the FOXO-dependent developmental process of Dauer formation in C. elegans. Eggs of CB1370 animals were hedged and grown at 23 °C (left panel) or 22 °C (right panel) in the presence of FoxOi or loperamide at the indicated concentrations. In the absence of compounds (0 μM), the fraction of animals forming Dauer was 20.2% (left panel) and 3.2% (right panel). Compound-induced fold changes of this fraction are shown. N = 3; 100 animals per condition and replicate. C. Representative images of developmental defects in zebrafish larvae following 48h FoxOi treatment and rescue with loperamide. D. Quantification of insulin or glucagon-positive cells following loperamide treatment in zebrafish larvae. N_control = 12; N_loperamide = 21. E. Representative images of pancreatic human islets stained for insulin and glucagon. Scale bars = 10 μm. On the right: Summary of the population distribution change in the human islets. F. Measurement of INS and GCG transcription in human islets treated with loperamide by RT-qPCR. All the data points are normalized to DMSO control, n = 4. G. Transcription of GCG, INS, and PDX1 in pancreatic islets from human diabetic donors treated for 48h with loperamide, as measured by RT-qPCR, n = 2. H. Glucose-stimulated insulin secretion assay on diabetic human islets pretreated with loperamide for 48 h, n = 2. Basal = 0.3 g/L glucose; stimulated = 3 g/L glucose. I. Relative insulin and Pdx1 mRNA levels in islets from db/db mice pretreated with loperamide for 48h.