Involvement of CRF2 signaling in enterocyte differentiation

Figure 6 Corticotropin releasing factor receptor 2 signaling alters expression of characteristic markers of enterocyte differentiation. A: Right panel: Detection of DPPIV and AP mRNA expression by RT-PCR during the kinetic of Caco-2 cell differentiation and after acute (5 h) or chronic (every day) exposure to 100 nmol/L Ucn3 of 21 d differentiated cells. GAPDH served as a housekeeping control. Quantification of KLF4 and AP mRNA from RT-PCR assays (lower panel). Data were expressed as fold increase of KLF4 or AP/GAPDH mRNA levels of differentiated (D7, D15, D21) vs undifferentiated cells (D0). Data represents means of three different experiments ± SEM. ^a,cP < 0.01 vs undifferentiated Caco-2 cells (D0), ^d,eP < 0.001 vs D0, ^bP < 0.05 vs differentiated Caco-2 cells (D21), ^fP < 0.01 vs D21, ^gP < 0.001 vs D21; Note that normality of distribution was not respected for DPPIV PCR. Left panel: Detection of DPPIV and AP mRNA expression by RT-PCR during the kinetic of HT-29 cell differentiation and after acute (5 h) or chronic (every day) exposure to 100 nmol/L Ucn3 of 10 d differentiated cells. GAPDH served as a housekeeping control. Quantification of DPPIV and AP mRNA from RT-PCR assays (lower panel). Data were expressed as fold increase of DPPIV and AP/GAPDH mRNA levels of differentiated (D6 and D10) vs undifferentiated cells (D0). Data represents means of three different experiments ± SEM. Data represents means of three different experiments ± SEM. ^a,dP < 0.01 vs undifferentiated HT-29 cells (D0); ^bP < 0.01 vs early differentiated HT-29 cells (D10), ^c,e,fP < 0.001 vs D10; B: Left panel: Detection of DPPIV protein expression by western blot during the kinetic of Caco-2 cell differentiation and after acute (5 h) or chronic (every day) exposure to 100 nmol/L Ucn3 of 21 d differentiated cells. Actin served as a loading control. Right panel: Quantification of DPPIV protein levels from western blot analysis. Data were expressed as fold increase of DPPIV/actin protein levels of differentiated (D7, D15, D21) vs undifferentiated cells (D0). Data represents means of three different experiments ± SEM. ^aP < 0.01 vs undifferentiated Caco-2 cells (D0), ^b,cP < 0.001 vs D0, ^dP < 0.01 vs differentiated Caco-2 cells (D21), ^eP < 0.001 vs D21. C and D: Detection of DPPIV (C) and AP (D) enzymatic activities during the kinetic of Caco-2 cell differentiation and after acute (5 h) or chronic (every day) exposure to 100 nmol/L Ucn3 of 21 d differentiated cells. Data were expressed as fold increase of enzymatic activities of differentiated (D7, D15, D21) vs undifferentiated cells (D0). Data represents means of three different experiments ± SEM. For C: ^a,bP < 0.001 vs undifferentiated Caco-2 cells (D0); ^cP < 0.01 vs differentiated Caco-2 cells (D21). For D: ^aP < 0.05 vs undifferentiated Caco-2 cells (D0), ^b,cP < 0.001 vs D0, ^dP < 0.05 vs differentiated Caco-2 cells (D21) and ^eP < 0.001 vs D21.