Fig 2: Serum from resistance-trained mice protects INS-1E cells from cytokine-induced apoptosis. INS-1E cells were incubated with conditioned medium containing 10% of serum from control or trained healthy mice for 24 h, followed by exposure to IL-1ß plus IFN-? for 24 h. Protein expression of iNOS (A), cleaved caspase-3 (B), BAX (C), and Bcl-2 (D) normalized by a-tubulin in INS-1E cells from different treatments as indicated in the graph (n = 3–6). BAX and Bcl-2 ratio is shown (E) (n = 5). Representative blots (F). Cell apoptosis was measured by HO and PI staining (n = 4) (G). Representative images from HO and PI stained cells (H). Data are the mean ± SEM. Letters shared in common between groups indicate no significant difference. Different letters indicate statistical difference between groups, p = 0.05 (one-way ANOVA).

Fig 3: Verification of Recellularization: (A) Immunofluorescence staining of a recellularized pancreas. The recellularized rat pancreas was stained with DAPI nuclear staining (blue), INS for INS-1E cells (green) and vWF for NAEC cells (red). B TEM in a recellularized pancreas showing that the INS-1E cells tended to aggregate into groups and that the NAEC cells were prone to colonize and adhere tightly within the parenchymal space

Fig 4: Loss of mesenchymal Sufu and Spop impairs pancreatic growth and differentiation. a E17.5 control embryonic gut displaying stomach (St), spleen (Spl), pancreas (Panc), and proximal intestine (Int). b Mesenchymal Sufu knockout (Bapx1Cre/+;Sufuf/f) exhibiting loss of external pancreas. c Heterozygous loss of Spop in Sufu knockout background (Bapx1Cre/+;Sufuf/f;Spopf/+). d Mesenchymal loss of both Sufu and Spop (Bapx1Cre/+;Sufuf/f;Spopf/f) leads to severe morphological dysregulation. e qPCR gene expression analysis for Hedgehog pathway members and targets in pancreatic mesenchyme upon Sufu and Spop deletion (n = 3 samples per genotype). f–i Histological images distinguishing highly cytoplasmic pancreatic tissue (pink eosin staining) in E17.5 control (f), Bapx1Cre/+;Sufuf/f (g), Bapx1Cre/+;Sufuf/f;Spopf/+ (h), and Bapx1Cre/+;Sufuf/f;Spopf/f (i) embryos (dashed line outlines pancreas). j Quantification of pancreatic volume (mm3) normalized to gut weight (mg) in Sufu and Spop mesenchymal mutants (n = 5 control samples, n = 3 samples per mutant genotype). k–n Immunostaining for INS and GCG in E17.5 control (k), Bapx1Cre/+;Sufuf/f (l), Bapx1Cre/+;Sufuf/f;Spopf/+ (m), and Bapx1Cre/+;Sufuf/f;Spopf/f (n) pancreata. o Assessment of INS+ to GCG+ cell number ratios in Sufu and Spop compound mutants, normalized to controls (n = 3 samples per genotype). Data are means ± SEM. n.s. denotes not significant, * denotes p < 0.05, ** denotes p < 0.005, *** denotes p < 0.0005 by Student’s un-paired, two tailed t-test. Scale bars: Whole mount; 1 mm, Histology; 500 µm, Immunofluorescence; 100 µm

Fig 5: Mesenchymal loss of Sufu and Spop impairs progenitor growth and beta cell genesis. a, b Immunostaining for the SOX2+ stomach domain (St) and PDX1+ pancreatic domain (Panc) in E10.5 control a and Bapx1Cre/+;Sufuf/f;Spopf/f mutants b embryos. c, d Immunostaining for E10.5 PDX1+ control c vs. mutant d pancreatic progenitors marked with thymidine analog, 5-bromo-2'-deoxyuridine (BrdU) 1 h after administration. e Assessment of the proportion of PDX1+ progenitors marked by BrdU as a measure of progenitor proliferation in mutants vs. controls (n = 4 samples per genotype). f, g Immunostaining for E13.5 NGN3+ control f vs. mutant g endocrine progenitors in the SOX9+ pancreatic progenitor pool. Arrows indicate non-specific staining. h Quantification of the proportion of NGN3+ committed endocrine progenitors out of the total NGN3+ and/or SOX9+ progenitor pool in mutants vs. controls (n = 3 control samples, n = 4 mutant samples). i, j Immunostaining for control i vs. mutant j INS+ cells labelled with BrdU after administration every 24 h during beta cell genesis (E14.5-E16.5). Arrows indicate representative BrdU+ labelled INS+ cells. k Assessment of INS+ cells labelled with BrdU after E14.5-E16.5 tracing as a measure of beta cell genesis in mutants vs. controls (n = 3 samples per genotype). l Diagram illustrating the temporal roles of mesenchymal Sufu and Spop throughout pancreatic development. Data are means ± SEM. n.s. denotes not significant, * denotes p < 0.05 by Student’s un-paired, two tailed t-test. Scale bars- 100 µm