Prospective evaluation and follow-up of nutritional status of children hospitalized in secondary-care level hospitals: a multicentre study.

Although disease-associated undernutrition is still an important problem in hospitalized children that is often underrecognized, follow-up studies evaluating post-discharge nutritional status of children with undernutrition are lacking. The aim of this multicentre prospective observational cohort study was to assess the rate of acute undernutrition (AU) and/or having a high nutritional risk (HR) in children on admission to seven secondary-care level Dutch hospitals and to evaluate the nutritional course of AU/HR group during admission and post-discharge. STRONGkids was used to indicate HR, and AU was based on anthropometric data (z-score < -2 for weight-for-age (WFA; <1 year) or weight-for-height (WFH; ≥1 year)). In total, 1985 patients were screened for AU/HR over a 12-month period. On admission, AU was present in 9.9% of screened children and 6.2% were classified as HR; 266 (13.4%) children comprised the AU/HR group (median age 2.4 years, median length of stay 3 days). In this group, further nutritional assessment by a dietitian during hospitalization occurred in 44% of children, whereas 38% received nutritional support. At follow-up 4-8 weeks post-discharge, 101 out of orginal 266 children in the AU/HR group (38%) had available paired anthropometric measurements to re-assess nutrition status. Significant improvement of WFA/WFH compared to admission (-2.48 vs. -1.51 SD; p < 0.001) and significant decline in AU rate from admission to outpatient follow-up (69.3% vs. 35.6%; p < 0.001) were shown. In conclusion, post-discharge nutritional status of children with undernutrition and/or high nutritional risk on admission to secondary-care level pediatric wards showed significant improvement, but about one-third remained undernourished. Findings warrant the need for a tailored post-discharge nutritional follow-up.

Severe neonatal enterovirus infection in twins with different outcomes: A case report.

Enteroviruses are among the most common causes of acute viral illness worldwide, and in neonates, the clinical course of these infections is heterogeneous. Severe complications, such as myocarditis, are associated with high mortality rates. In this case report, we present the clinical course of premature twins born at 35 weeks of gestational age, suffering from a severe neonatal enterovirus infection with cardiac involvement, which proved fatal in one of the twins. This course led to prompt identification in the other twin and facilitated timely transfer to a neonatal intensive care unit with neonatal hemodynamic expertise, and facilitated the timely transfer to a neonatal intensive care nit with hemodynamic expertise and immediate availability of AZCMO would it have been indicated. Early supportive therapy in the other twin contributed to a positive outcome. Therefore, we emphasize the importance of early recognition in averting adverse consequences. As a recommendation, we propose routine screening of enterovirus in viral panels for febrile newborns.

Safety of Thioguanine in Pediatric Inflammatory Bowel Disease: A Multi-Center Case Series.

OBJECTIVES: Thioguanine (TG) has been shown as a safe alternative in adults with inflammatory bowel disease (IBD) who did not tolerate conventional thiopurines [azathioprine (AZA)/mercaptopurine]. However, data in pediatric IBD are scarce. Therefore, we aimed to assess the safety of TG as maintenance therapy. METHODS: A retrospective, multicenter cohort study of children with IBD on TG was performed in the Netherlands. TG-related adverse events (AE) were assessed and listed according to the common terminology criteria for AE. RESULTS: Thirty-six children with IBD (median age 14.5 years) on TG (median dose 15 mg/day) were included in 6 centers. Five AE occurred during follow-up [pancreatitis (grade 3), hepatotoxicity (grade 3) (n = 2), Clostridium difficile infection (grade 2), and abdominal pain (grade 2)]. All patients (n = 8) with a previously AZA-induced pancreatitis did not redevelop pancreatitis on TG. CONCLUSIONS: In pediatric IBD, TG seems a safe alternative in case of AZA-induced pancreatitis. Further research assessing long-term TG-related safety and efficacy is needed.

Evaluation of exclusive enteral nutrition and corticosteroid induction treatment in new-onset moderate-to-severe luminal paediatric Crohn's disease.

To induce remission in luminal paediatric Crohn's disease (CD), the ESPGHAN/ECCO guideline recommends treatment with exclusive enteral nutrition (EEN) or oral corticosteroids. In newly diagnosed moderate-to-severe paediatric CD patients, we determined the proportion of patients in which EEN or corticosteroids induced remission and maintained remission on azathioprine monotherapy. We included patients from the "TISKids" study assigned to the conventional treatment arm. Patients were aged 3-17 years and had new-onset, untreated luminal CD with weighted paediatric CD activity index (wPCDAI) > 40. Induction treatment consisted of EEN or oral corticosteroids; all received azathioprine maintenance treatment from start of treatment. The primary outcome of this study was endoscopic remission defined as a SES-CD score < 3 without treatment escalation at week 10. Secondary outcomes included proportion of patients without treatment escalation at week 52. In total, 27/47 patients received EEN and 20/47 corticosteroids. At baseline, patient demographics and several inflammation parameters were similar between the two treatment groups. At 10 weeks, clinical remission rates were 7/23 (30%) for EEN and 7/19 (37%) for corticosteroids (p = 0.661). Twenty-nine of 47 consented to endoscopy at 10 weeks, showing endoscopic remission rates without treatment escalation in 2/16 (13%) of EEN-treated patients and in 1/13 (8%) of corticosteroid-treated patients (p = 1.00). At week 52, 23/27 (85%) EEN-treated patients received treatment escalation (median 14 weeks) and 13/20 (65%) corticosteroid-treated patients (median 27 weeks), p = 0.070.Conclusion: In children with moderate-to-severe newly diagnosed CD, induction treatment with EEN or CS regularly is insufficient to achieve endoscopic remission without treatment escalation at week 10. Trial registration number: NCT02517684 What is Known: • Endoscopic remission is associated with a low risk of disease progression. • FL-IFX was superior to conventional treatment in achieving and maintaining remission in paediatric patients with moderate-to-severe CD the first year from diagnosis. What is New: • In children with newly diagnosed moderate-to-severe CD, clinical remission rates and endoscopic remission rates without treatment escalation at week 10 were 30% and 13% after EEN and 37% and 8% after corticosteroid induction treatment. • The current treatment target was often not achieved by either EEN or corticosteroid induction treatment after bridging to azathioprine.

Skills or Pills: Randomized Trial Comparing Hypnotherapy to Medical Treatment in Children With Functional Nausea.

BACKGROUND & AIMS: The potential effectiveness of gut-directed hypnotherapy (HT) is unknown for pediatric chronic nausea. This randomized controlled trial compared HT with standard medical treatment (SMT). METHODS: One hundred children (ages, 8-18 y) with chronic nausea and fulfilling functional nausea (FN) or functional dyspepsia (FD) criteria were allocated randomly (1:1) to HT or SMT, with a 3-month intervention period. Outcomes were assessed at baseline, at the halfway point, after treatment, and at the 6- and 12-month follow-up evaluation. Children scored nausea symptoms in a 7-day diary. The primary outcome was treatment success, defined as a reduction in nausea of 50% or more, at the 12-month follow-up evaluation. Secondary outcomes included adequate relief of nausea. RESULTS: After treatment and at the 6-month follow-up evaluation, there was a trend toward higher treatment success in the HT group compared with the SMT group (45% vs 26%, P = .052; and 57% vs 40%, P = .099, respectively). At 12 months, treatment success was similar in both groups (60% in the HT group and 55% in the SMT group; P = .667). In the FN group, significantly higher success rates were found for HT, but no differences were found in patients with FD. Adequate relief was significantly higher in the HT group than in the SMT group at the 6-month follow-up evaluation (children: 81% vs 55%, P = .014; parents: 79% vs 53%; P = .016), but not at the 12-month follow-up evaluation. CONCLUSIONS: HT and SMT were effective in reducing nausea symptoms in children with FN and FD. In children with FN, HT was more effective than SMT during and after the first 6 months of treatment. Therefore, HT and SMT, applied separately or in combination, should be offered to children with FN as a treatment option (Clinical trials registration number: NTR5814).

First-line treatment with infliximab versus conventional treatment in children with newly diagnosed moderate-to-severe Crohn's disease: an open-label multicentre randomised controlled trial.

OBJECTIVE: In newly diagnosed paediatric patients with moderate-to-severe Crohn's disease (CD), infliximab (IFX) is initiated once exclusive enteral nutrition (EEN), corticosteroid and immunomodulator therapies have failed. We aimed to investigate whether starting first-line IFX (FL-IFX) is more effective to achieve and maintain remission than conventional treatment. DESIGN: In this multicentre open-label randomised controlled trial, untreated patients with a new diagnosis of CD (3-17 years old, weighted Paediatric CD Activity Index score (wPCDAI) >40) were assigned to groups that received five infusions of 5 mg/kg IFX at weeks 0, 2, 6, 14 and 22 (FL-IFX), or EEN or oral prednisolone (1 mg/kg, maximum 40 mg) (conventional). The primary outcome was clinical remission on azathioprine, defined as a wPCDAI <12.5 at week 52, without need for treatment escalation, using intention-to-treat analysis. RESULTS: 100 patients were included, 50 in the FL-IFX group and 50 in the conventional group. Four patients did not receive treatment as per protocol. At week 10, a higher proportion of patients in the FL-IFX group than in the conventional group achieved clinical (59% vs 34%, respectively, p=0.021) and endoscopic remission (59% vs 17%, respectively, p=0.001). At week 52, the proportion of patients in clinical remission was not significantly different (p=0.421). However, 19/46 (41%) patients in the FL-IFX group were in clinical remission on azathioprine monotherapy without need for treatment escalation vs 7/48 (15%) in the conventional group (p=0.004). CONCLUSIONS: FL-IFX was superior to conventional treatment in achieving short-term clinical and endoscopic remission, and had greater likelihood of maintaining clinical remission at week 52 on azathioprine monotherapy. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov Registry (NCT02517684).

Response to Vaccination in Infants Exposed to Antitumor Necrosis Factor Alpha In Utero.

In this retrospective cohort study, the response to routinely administered Haemophilus influenzae type B vaccine, pneumococcal and pertussis vaccinations in 27 children exposed to antitumor necrosis factor alpha (anti-TNFα) during pregnancy was measured. The overall vaccination response seems comparable for children exposed to anti-TNFα and healthy infants. After primary vaccination series, inadequate response was present in some patients and might be related to exposure to anti-TNFα.

Illness Perceptions and Depression Are Associated with Health-Related Quality of Life in Youth with Inflammatory Bowel Disease.

BACKGROUND: In youth with inflammatory bowel disease (IBD), health-related quality of life (HRQOL) has been shown to be affected by individual disease factors and specific psychological factors. The innovative aim of this study is to examine the combined impact of psychological factors (illness perceptions, cognitive coping, anxiety, and depression) on HRQOL, over and above the associations of demographic and disease factors with HRQOL in youth with IBD. METHOD: Data on clinical disease activity, illness perceptions, cognitive coping, anxiety, depression, and HRQOL were prospectively collected in 262 consecutive youth (age 10-20, 46.6% male) with confirmed IBD. Multiple linear regression analyses tested the associations of demographic, disease, and psychological variables with HRQOL in separate groups for Crohn's disease (CD; N = 147) and ulcerative colitis and IBD unclassified (UC/IBD-U; N = 115), using age-specific validated instruments. RESULTS: In both disease groups, more negative illness perceptions (ß = - .412; ß = - .438, p < .001) and more depression (ß = - .454; ß = - .279, p < .001) were related to lower HRQOL. In the UC/IBD-U group, more anxiety was related to lower HRQOL (ß = - .201, p = .001). The model with the psychological variables explained a large and significant amount of variance in both groups: 74% and 83%, respectively (p < .001). CONCLUSION: In 10-20-year-old IBD patients, negative illness perceptions and depression were significantly and more strongly associated with lower HRQOL than demographic and disease factors. Thus, it is important to integrate psychological factors in the treatment for IBD patients. To improve HRQOL in young IBD patients, psychological interventions should be targeted at negative illness perceptions and depression.

Gut-directed hypnotherapy versus standard medical treatment for nausea in children with functional nausea or functional dyspepsia: protocol of a multicentre randomised trial.

INTRODUCTION: The treatment of chronic functional nausea or nausea due to functional dyspepsia in children is generally symptomatic. Moreover, these disorders pose a risk for worse psychosocial and health outcomes in children. Hypnotherapy (HT), by its ability to positively influence gastrointestinal and psychosocial functioning, may be an effective treatment for chronic nausea. METHODS AND ANALYSIS: To test efficacy, this multicentre, parallel, randomised controlled, open label trial evaluates whether gut-directed HT is superior to standard medical treatment (SMT) for reducing nausea. The study will be conducted at eleven academic and non-academic hospitals across the Netherlands. A total of 100 children (8-18 years), fulfilling the Rome IV criteria for chronic idiopathic nausea or functional dyspepsia with prominent nausea, will be randomly allocated (1:1) to receive HT or SMT. Children allocated to the HT group will receive six sessions of HT during 3 months, while children allocated to the SMT group will receive six sessions of SMT+supportive therapy during the same period. The primary outcome will be the difference in the proportion of children with at least 50% reduction of nausea, compared with baseline at 12 months' follow-up. Secondary outcomes include the changes in abdominal pain, dyspeptic symptoms, quality of life, anxiety, depression, school absences, parental absence of work, healthcare costs and adequate relief of symptoms, measured directly after treatment, 6 and 12 months' follow-up. If HT proves effective for reducing nausea, it may become a new treatment strategy to treat children with chronic functional nausea or functional dyspepsia with prominent nausea. ETHICS AND DISSEMINATION: Results of the study will be publicly disclosed to the public, without any restrictions, in peer-reviewed journal and international conferences. The study is approved by the Medical Research Ethics Committees United (MEC-U) in the Netherlands. TRIAL REGISTRATION NUMBER: NTR5814.

Translating Sepsis-3 Criteria in Children: Prognostic Accuracy of Age-Adjusted Quick SOFA Score in Children Visiting the Emergency Department With Suspected Bacterial Infection.

Background: Recent attempts to translate Sepsis-3 criteria to children have been restricted to PICU patients and did not target children in emergency departments (ED). We assessed the prognostic accuracy of the age-adjusted quick Sequential Organ Failure Assessment score (qSOFA) and compared the performance to SIRS and the quick Pediatric Logistic Organ Dysfunction-2 score (qPELOD-2). We studied whether the addition of lactate (qSOFA-L) would increase prognostic accuracy. Methods: Non-academic, single-center, retrospective study in children visiting the ED and admitted with suspected bacterial infection between March 2013 and January 2018. We defined suspected bacterial infection as initiation of antibiotic therapy within 24 h after ED entry. Age-adjusted qSOFA, SIRS, qPELOD-2, and qSOFA-L scores were compared by area under the receiver operating characteristics curve (AUROC) analysis. Primary outcome measure was PICU transfer and/or mortality and secondary outcome was prolonged hospital length of stay. Results: We included 864 ED visits [474 (55%) male; median age 2.5 years; IQR 9 months-6 years], of which 18 were transferred to a PICU and 6 ended in death [composite outcome PICU transfer and/or mortality; 23 admissions (2.7%)]. 179 (22.2%) admissions resulted in prolonged hospital length of stay. PICU transfer and/or death was present in 22.5% of visits with qSOFA≥2 (n = 40) compared to 2.0% of visits with qSOFA<2 (n = 444) (p < 0.01). qSOFA tends to be the best predictor of PICU transfer and/or mortality (AUROC 0.72 (95% CI, 0.57-0.86) compared to SIRS [0.64 (95% CI, 0.53-0.74), p = 0.23] and qPELOD-2 [0.60 (95% CI, 0.45-0.76), p = 0.03)]. Prolonged hospital length of stay was poorly predicted by qSOFA (AUROC 0.53, 95% CI 0.46-0.59), SIRS (0.49, 95% CI 0.44-0.54), and qPELOD-2 (0.51, 95%CI 0.45-0.57). qSOFA-L resulted in an AUROC of 0.67 (95% CI, 0.50-0.84) for PICU transfer and/or mortality and an AUROC of 0.56 (95% CI, 0.46-0.67) for prolonged hospital length of stay. Conclusion: The currently proposed bedside risk-stratification tool of Sepsis-3 criteria, qSOFA, shows moderate prognostic accuracy for PICU transfer and/or mortality in children visiting the ED with suspected bacterial infection. The addition of lactate did not improve prognostic accuracy. Future prospective studies in larger ED populations are needed to further determine the utility of the qSOFA score.

Home-Based Hypnotherapy Self-exercises vs Individual Hypnotherapy With a Therapist for Treatment of Pediatric Irritable Bowel Syndrome, Functional Abdominal Pain, or Functional Abdominal Pain Syndrome: A Randomized Clinical Trial.

Importance: 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 Participants: This 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. Interventions: The 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 Measures: Primary 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 Relevance: Long-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. Trial Registration: trialregister.nl Identifier: NTR2725.

Glucose hydrogen breath test for small intestinal bacterial overgrowth in children with abdominal pain-related functional gastrointestinal disorders.

OBJECTIVES: A potential link between small intestinal bacterial overgrowth (SIBO) and abdominal pain-related functional gastrointestinal disorders (AP-FGID) has been suggested by symptom similarities and by the reported prevalence of SIBO in children with irritable bowel syndrome (IBS) and functional AP. The aim of this study is to evaluate the prevalence of SIBO using the glucose hydrogen breath test (GHBT), in a cohort of Dutch children with AP-FGID fulfilling the Rome III criteria, and to identify potential predictors. METHODS: Children ages 6 to 18 years with AP-FGID fulfilling the Rome III criteria were included. All of the children underwent a GHBT. SIBO was diagnosed if the fasting breath hydrogen concentration was ≥20 ppm or an increase in H2 levels of ≥12 ppm above the baseline value was measured after ingestion of glucose. Gastrointestinal symptoms were collected using a standardised AP questionnaire. RESULTS: A total of 161 Dutch children with AP-FGID were enrolled. Twenty-three patients (14.3%) were diagnosed as having SIBO, as assessed by GHBT; 78% of the children diagnosed as having SIBO had fasting hydrogen levels ≥20 ppm. IBS was significantly more found in children with SIBO compared with children without SIBO (P = 0.001). An altered defecation pattern (ie, change in frequency or form of stool) (P = 0.013), loss of appetite (P = 0.007), and belching (P = 0.023) were significantly more found in children with SIBO compared with those without SIBO. CONCLUSIONS: SIBO is present in 14.3% of children presenting with AP-FGID. IBS, altered defecation pattern, loss of appetite, and belching were predictors for SIBO in children with AP-FGID.

Are constipation drugs effective and safe to be used in children? A review of the literature.

INTRODUCTION: Functional constipation is a common and often enduring problem in childhood. Although functional constipation is well defined by the Rome III criteria, these criteria have not always been integrated in general practice. Early diagnosis and treatment are key factors with respect to successful long-term outcome, as chronic constipation has a negative effect on the quality of life and is a burden for the public healthcare system. The safety of laxatives used for paediatric-functional constipation is based on well-designed trials carried out mostly in adults. Therefore, we conducted a review of the literature outlining the evidence for the efficacy and safety of laxatives used in chronic paediatric-functional constipation. AREAS COVERED: This review clearly shows a lack of large well-designed placebo-controlled trials in children with constipation. Therefore, any interpretation with regards to the evidence for the effectiveness or safety of laxatives used in children is difficult and we extended the search for side effects to the adult literature. EXPERT OPINION: In adults, new promising drugs are on the virtue of breaking through in the treatment of chronic constipation. Carrying out well-defined placebo-controlled trials in children should be the next step before using these drugs.

Hepatocyte nuclear factor-1alpha is required for expression but dispensable for histone acetylation of the lactase-phlorizin hydrolase gene in vivo.

Hepatocyte nuclear factor-1alpha (HNF-1alpha) is a modified homeodomain-containing transcription factor that has been implicated in the regulation of intestinal genes. To define the importance and underlying mechanism of HNF-1alpha for the regulation of intestinal gene expression in vivo, we analyzed the expression of the intestinal differentiation markers and putative HNF-1alpha targets lactase-phlorizin hydrolase (LPH) and sucrase-isomaltase (SI) in hnf1alpha null mice. We found that in adult jejunum, LPH mRNA in hnf1alpha(-/-) mice was reduced 95% compared with wild-type controls (P < 0.01, n = 4), whereas SI mRNA was virtually identical to that in wild-type mice. Furthermore, SI mRNA abundance was unchanged in the absence of HNF-1alpha along the length of the adult mouse small intestine as well as in newborn jejunum. We found that HNF-1alpha occupies the promoters of both the LPH and SI genes in vivo. However, in contrast to liver and pancreas, where HNF-1alpha regulates target genes by recruitment of histone acetyl transferase activity to the promoter, the histone acetylation state of the LPH and SI promoters was not affected by the presence or absence of HNF-1alpha. Finally, we showed that a subset of hypothesized intestinal target genes is regulated by HNF-1alpha in vivo and that this regulation occurs in a defined tissue-specific and developmental context. These data indicate that HNF-1alpha is an activator of a subset of intestinal genes and induces these genes through an alternative mechanism in which it is dispensable for chromatin remodeling.

Complex regulation of the lactase-phlorizin hydrolase promoter by GATA-4.

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.

Novel interaction at the Cdx-2 binding sites of the lactase-phlorizin hydrolase promoter.

Cdx-2 is an intestine-specific homeodomain-containing transcription factor that activates the promoters of intestinal genes through specific interactions with the consensus, TTTAT/C. Here, we demonstrate that Cdx-2 interacts with the lactase-phlorizin hydrolase (LPH) promoter at cis-element (CE)-LPH1a (-54 to -40 bp) as well as the LPH TATA-box. Affinity comparisons between SIF-1, CE-LPH1a, and the LPH TATA-box revealed that the TATA-box has the lowest affinity for Cdx-2. Characterization of CE-LPH1a using EMSAs revealed binding of a novel, non-Cdx-2 complex in multiple cell lines that bind to sequence that is different from that of the Cdx-2 binding site. Heterologous promoter analysis in transient transfection assays revealed a repressor function for this protein, and thus, it was designated as nuclear factor-LPH1/repressor (NF-LPH1/R). These data are consistent with the hypothesis that NF-LPH1/R represses LPH gene expression in non-Cdx-2-producing cells, and that this repression is released in cells that synthesize Cdx-2, such as those in the intestinal epithelium.

Hepatocyte nuclear factor-1 alpha, GATA-4, and caudal related homeodomain protein Cdx2 interact functionally to modulate intestinal gene transcription. Implication for the developmental regulation of the sucrase-isomaltase gene.

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.

Physical interaction between GATA-5 and hepatocyte nuclear factor-1alpha results in synergistic activation of the human lactase-phlorizin hydrolase promoter.

GATA-4, -5, and -6 zinc finger and hepatocyte nuclear factor-1alpha (HNF-1alpha) homeodomain transcription factors are expressed in the intestinal epithelium and synergistically activate the promoter of intestinal genes. Here, we demonstrate that GATA-5 and HNF-1alpha physically associate both in vivo and in vitro and that this interaction is necessary for cooperative activation of the lactase-phlorizin hydrolase promoter. Furthermore, physical association is mediated by the C-terminal zinc finger of GATA factors and the homeodomain of HNF-1alpha. Deletion of HNF-1alpha activation domains or interruption of HNF-1-binding sites in the lactase-phlorizin hydrolase promoter resulted in a complete loss of cooperativity, whereas deletion of GATA-5 activation domains or interruption of GATA-binding sites resulted in a reduction, but not an elimination, of cooperativity. We hypothesize that GATA/HNF-1alpha cooperativity is mediated by HNF-1alpha through its activation domains, which are oriented for high levels of activation through binding to DNA and physical association with GATA factors. These data suggest a paradigm whereby intestine-specific gene expression is regulated by unique interactions among tissue-restricted transcription factors coexpressed in the intestine. Parallel mechanisms in other tissues as well as in Drosophila suggest that zinc finger/homeodomain interactions are an efficient pathway of cooperative activation of gene transcription that has been conserved throughout evolution.