Sucrase-isomaltase (SI), an intestine-specific gene, is induced in the differentiated small intestinal villous epithelium during the suckling-weaning transition in mice. We have previously identified cis-acting elements within a short evolutionarily conserved SI promoter. However, the nature and profile of expression of the interacting proteins have not been fully characterized during this developmental transition. Herein, we show that hepatocyte nuclear factor-1 alpha (HNF-1 alpha), GATA-4, and caudal related homeodomain proteins Cdx2 and Cdx1 are the primary transcription factors from the adult mouse intestinal epithelium to interact with the SIF3, GATA, and SIF1 elements of the SI promoter. We wanted to study whether HNF-1 alpha, GATA-4, and Cdx2 can cooperate in the regulation of SI gene expression. Immunolocalization experiments revealed that HNF-1 alpha is detected in rare epithelial cells of suckling mice and becomes progressively more expressed in the villous epithelial cells during the suckling-weaning transition. GATA-4 protein is expressed exclusively in villous differentiated epithelial cells of the proximal small intestine, decreases in expression in the ileum, and becomes undetectable in the colon. HNF-1 alpha, GATA-4, and Cdx2 interact in vitro and in vivo. These factors activate SI promoter activity in cotransfection experiments where GATA-4 requires the presence of both HNF-1 alpha and Cdx2. These findings imply a combinatory role of HNF-1 alpha, Cdx2, and GATA-4 for the time- and position-dependent regulation of SI transcription during development.

The effects of GATA-4, -5, and -6, hepatocyte nuclear factor-1 alpha (HNF-1 alpha) and -beta, and Cdx-2 on the rat and human lactase-phlorizin hydrolase (LPH) and human sucrase-isomaltase (SI) promoters were studied using transient cotransfection assays in Caco-2 cells. GATA factors and HNF-1 alpha were strong activators of the LPH promoters, whereas HNF-1 alpha and Cdx-2 were strong activators of the SI promoter, although GATA factors were also necessary for maximal activation of the SI gene. Cotransfection of GATA-5 and HNF-1 alpha together resulted in a higher activation of all three promoters than the sum of the activation by either factor alone, demonstrating functional cooperativity. In the human LPH promoter, an intact HNF-1 binding site was required for functional synergy. This study is the first to demonstrate 1) differential activation of the LPH and SI promoters by multiple transcription factors cotransfected singly and in combination and 2) that GATA and HNF-1 transcription factors cooperatively activate intestinal gene promoters. Synergistic activation is a mechanism by which higher levels of tissue-specific expression might be attained by overlapping expression of specific transcription factors.

Individual gut-directed hypnotherapy (HT) is effective in pediatric irritable bowel syndrome (IBS) and functional abdominal pain or functional abdominal pain syndrome (FAP[S]). It is, however, unavailable to many children.OBJECTIVE To compare the effectiveness of HT by means of home-based self-exercises using a CD with that of individual HT (iHT) performed by qualified therapists. DESIGN, SETTING, AND PARTICIPANTSThis noninferiority randomized clinical trial with a follow-up of 1 year after the end of treatment was conducted from July 15, 2011, through June 24, 2013, at 9 secondary and tertiary care centers throughout the Netherlands. A total of 303 children were eligible to participate. Of those, 260 children (aged 8-18 years) with IBS or FAP(S) were included in this study. Children were randomized (1:1 ratio) to home-based HT with a CD (CD group) or iHT performed by qualified therapists (iHT group). No children withdrew from the study because of adverse effects. INTERVENTIONSThe CD group was instructed to perform exercises 5 times per week or more for 3 months. The iHT group consisted of 6 sessions during 3 months. MAIN OUTCOMES AND MEASURESPrimary outcomes were treatment success directly after treatment and after 1-year follow-up. Treatment success was defined as a 50% or greater reduction in pain frequency and intensity scores. The noninferiority limit was set at 50% treatment success in the CD group, with a maximum of 25% difference in treatment success with the iHT group after 1-year follow-up. Modified intention-to-treat analyses were performed.RESULTS A total of 132 children were assigned to the CD group and 128 to the iHT group; 250 children were analyzed (126 in the CD group and 124 in the iHT group) (mean [SD] age, 13.4 [2.9] years in the CD group and 13.3 [2.8] years in the iHT group; 94 female [74.6%] in the CD group and 85 [68.5%] in the iHT group). Directly after treatment, 46 children (36.8%) in the CD group and 62 (50.1%) in the iHT group were successfully treated. After 1-year follow-up, the 62.1% treatment success in the CD group was noninferior to the 71.0% in the iHT group (difference, −8.9%; 90% CI, −18.9% to 0.7%; P = .002). CONCLUSIONS AND RELEVANCELong-term effectiveness of home-based HT with a CD is noninferior to iHT performed by therapists in pediatric IBS or FAP(S). Treatment with hypnosis using a CD provides an attractive treatment option for these children.

Lactase-phlorizin hydrolase (LPH), a marker of intestinal differentiation, is expressed in absorptive enterocytes on small intestinal villi in a tightly regulated pattern along the proximal-distal axis. The LPH promoter contains binding sites that mediate activation by members of the GATA-4, -5, and -6 subfamily, but little is known about their individual contribution to LPH regulation in vivo. Here, we show that GATA-4 is the principal GATA factor from adult mouse intestinal epithelial cells that binds to the mouse LPH promoter, and its expression is highly correlated with that of LPH mRNA in jejunum and ileum. GATA-4 cooperates with hepatocyte nuclear factor (HNF)-1alpha to synergistically activate the LPH promoter by a mechanism identical to that previously characterized for GATA-5/HNF-1alpha, requiring physical association between GATA-4 and HNF-1alpha and intact HNF-1 binding sites on the LPH promoter. GATA-4 also activates the LPH promoter independently of HNF-1alpha, in contrast to GATA-5, which is unable to activate the LPH promoter in the absence of HNF-1alpha. GATA-4-specific activation requires intact GATA binding sites on the LPH promoter and was mapped by domain-swapping experiments to the zinc finger and basic regions. However, the difference in the capacity between GATA-4 and GATA-5 to activate the LPH promoter was not due to a difference in affinity for binding to GATA binding sites on the LPH promoter. These data indicate that GATA-4 is a key regulator of LPH gene expression that may function through an evolutionarily conserved mechanism involving cooperativity with an HNF-1alpha and/or a GATA-specific pathway independent of HNF-1alpha.