re 5a), a trend conditions inin untreated animals (Figure5a), a trend that was also seen for Claudin-2 exwas also noticed for Claudin-2 pression (Figure 5d, p 0.05). Having said that, all round, in our in vivo the Selenof Selenof PLK4 MedChemExpress expression (Figure 5d, p 0.05). Nonetheless, all round, in our in vivo model,model, the genotype showed showed small to no effect on mRNA expression of tight Nav1.2 site junction proteins genotype tiny to no impact on mRNA expression of tight junction proteins Claudin-1 (Cldn-1), two (Cldn-2) and 15 (Cldn-15). Western blot analyses Western blot analyses claudin-2 overClaudin-1 (Cldn-1), two (Cldn-2) and 15 (Cldn-15). showed low expression ofshowed low all, and no visible variations in protein visible differences in protein expression for expression of claudin-2 general, and no expression for Claudin-1 or Claudin-3 (Figure 5g) or Claudin-2 (Figure (Figure 5g) WT and KO (Figure 5h) involving WT and KO mice. It Claudin-1 or Claudin-35h) amongst or Claudin-2mice. It should be noted that mRNA expression be noted that mRNA expression of these tight junction genes in AOM/DSS-treated must of those tight junction genes in AOM/DSS-treated animals, interestingly, showed a positiveinterestingly, showed a positivewith substantial impact on expression of with animals, correlation with dietary selenium, correlation with dietary selenium, Cldn-2 (p = 0.0016) and on expression of Cldn-2 (p = 0.0016) and Cldn-15 (p = 0.0008). significant influence Cldn-15 (p = 0.0008). As well as tight junction genes, we also evaluated the mRNA expression of genes typically related with adherens junctions and other barrier integrity functions in manage animals’ colon scrapes and in colon tumor tissues (Figure S8). Dietary selenium levels appeared to influence mRNA expression with the transmembrane glycoprotein epithelial cell adhesion molecule (EpCAM), Nectin cell adhesion molecule (Nectin)-2, membrane-associated carbonic anhydrase 4 (Car4), and also the secreted glycoprotein mucin two (Muc2) in either WT or KO mice, or both. Interestingly, Selenof -genotype did not appear to considerably influence mRNA expression from the investigated genes in colons of mice, except for Epcam, which was significantly lower in tumors of Selenof-KO mice compared to WT mice, but only at higher selenium levels. On the other hand, even though gene expression of tight junction and adherens junction genes weren’t drastically altered amongst Selenof-KO mice and their WT littermates, the dramatically increased size of goblet cells in KO mice suggest structural changes relevant to colon tumorigenesis.Int. J. Mol. Sci. 2021, 22, 10651 Int. J. Mol. Sci. 2021, 221,ten of 19 ten ofFigure five. Expression of tight junction Claudin genes. mRNA expression was measured with qPCR Figure 5. Expression of tight junction Claudin genes. mRNA expression was measured with qPCR in (a,c,e) colon scrapes of control mice and (b,d,f) colon tumors ofof AOM/DSS-treated mice. Mean in (a,c,e) colon scrapes of manage mice and (b,d,f) colon tumors AOM/DSS-treated mice. Mean (N = 4) + SEM, 2-way ANOVA, followed by Tukey’s post hoc analyses to evaluate KO vs. WT by diet plan; (N = four) + SEM, 2-way ANOVA, followed by Tukey’s post hoc analyses to compare KO vs. WT by diet regime; letters indicate statistically considerable differences. Protein expression of (g) Claudin-1 and Claudinletters indicate statistically substantial variations. Protein expression of (g) Claudin-1 and Claudin-3, 3, and (h) Claudin-2 in colon scrapes of manage mice on selenium-specific diets was asse
