Conserved roles for Hnf4 family transcription factors in zebrafish development and intestinal function.

Transcription factors play important roles in the development of the intestinal epithelium and its ability to respond to endocrine, nutritional, and microbial signals. Hepatocyte nuclear factor 4 family nuclear receptors are liganded transcription factors that are critical for the development and function of multiple digestive organs in vertebrates, including the intestinal epithelium. Zebrafish have 3 hepatocyte nuclear factor 4 homologs, of which, hnf4a was previously shown to mediate intestinal responses to microbiota in zebrafish larvae. To discern the functions of other hepatocyte nuclear factor 4 family members in zebrafish development and intestinal function, we created and characterized mutations in hnf4g and hnf4b. We addressed the possibility of genetic redundancy amongst these factors by creating double and triple mutants which showed different rates of survival, including apparent early lethality in hnf4a; hnf4b double mutants and triple mutants. RNA sequencing performed on digestive tracts from single and double mutant larvae revealed extensive changes in intestinal gene expression in hnf4a mutants that were amplified in hnf4a; hnf4g mutants, but limited in hnf4g mutants. Changes in hnf4a and hnf4a; hnf4g mutants were reminiscent of those seen in mice including decreased expression of genes involved in intestinal function and increased expression of cell proliferation genes, and were validated using transgenic reporters and EdU labeling in the intestinal epithelium. Gnotobiotics combined with RNA sequencing also showed hnf4g has subtler roles than hnf4a in host responses to microbiota. Overall, phenotypic changes in hnf4a single mutants were strongly enhanced in hnf4a; hnf4g double mutants, suggesting a conserved partial genetic redundancy between hnf4a and hnf4g in the vertebrate intestine.

Transcriptional Integration of Distinct Microbial and Nutritional Signals by the Small Intestinal Epithelium.

BACKGROUND & AIMS: The intestine constantly interprets and adapts to complex combinations of dietary and microbial stimuli. However, the transcriptional strategies by which the intestinal epithelium integrates these coincident sources of information remain unresolved. We recently found that microbiota colonization suppresses epithelial activity of hepatocyte nuclear factor 4 nuclear receptor transcription factors, but their integrative regulation was unknown. METHODS: We compared adult mice reared germ-free or conventionalized with a microbiota either fed normally or after a single high-fat meal. Preparations of unsorted jejunal intestinal epithelial cells were queried using lipidomics and genome-wide assays for RNA sequencing and ChIP sequencing for the activating histone mark H3K27ac and hepatocyte nuclear factor 4 alpha. RESULTS: Analysis of lipid classes, genes, and regulatory regions identified distinct nutritional and microbial responses but also simultaneous influence of both stimuli. H3K27ac sites preferentially increased by high-fat meal in the presence of microbes neighbor lipid anabolism and proliferation genes, were previously identified intestinal stem cell regulatory regions, and were not hepatocyte nuclear factor 4 alpha targets. In contrast, H3K27ac sites preferentially increased by high-fat meal in the absence of microbes neighbor targets of the energy homeostasis regulator peroxisome proliferator activated receptor alpha, neighbored fatty acid oxidation genes, were previously identified enterocyte regulatory regions, and were hepatocyte factor 4 alpha bound. CONCLUSIONS: Hepatocyte factor 4 alpha supports a differentiated enterocyte and fatty acid oxidation program in germ-free mice, and that suppression of hepatocyte factor 4 alpha by the combination of microbes and high-fat meal may result in preferential activation of intestinal epithelial cell proliferation programs. This identifies potential transcriptional mechanisms for intestinal adaptation to multiple signals and how microbiota may modulate intestinal lipid absorption, epithelial cell renewal, and systemic energy balance.

Predictors of Prolonged Breast Milk Provision to Very Low Birth Weight Infants.

OBJECTIVE: To identify factors associated with prolonged maternal breast milk (BM) provision in very low birth weight (VLBW) infants. STUDY DESIGN: This was a cohort study of VLBW infants who initially received maternal BM and were born at one of 197 neonatal intensive care units managed by the Pediatrix Medical Group from 2010 to 2012. We used multivariable logistic regression to identify demographic, clinical, and maternal factors associated with provision of maternal BM on day of life (DOL) 30 and at discharge. RESULTS: Median gestational age for all infants was 28 weeks (25th, 75th percentiles: 26, 30), and median maternal age was 28 years (23, 33). Of 8806 infants, 6261 (71%) received maternal BM on DOL 30, and 4003 of 8097 (49%) received maternal BM at discharge to home. Predictors of maternal BM provision at DOL 30 included increased maternal age, white maternal race, absence of history of necrotizing enterocolitis or late-onset sepsis, higher household income, lower education level, lack of donor BM exposure, and lower gestational age. CONCLUSIONS: Our results suggest that maternal-infant demographic and clinical factors and household neighborhood socioeconomic characteristics were associated with provision of maternal BM at 30 postnatal days to VLBW infants. Identification of these factors allows providers to anticipate mothers' needs and develop tailored interventions designed to improve rates of prolonged maternal BM provision and infant outcomes.

The association of C-reactive protein and physical activity among a church-based population of African Americans.

OBJECTIVE: Regular physical activity can reduce systemic inflammation and, thereby, the burden of chronic inflammatory-related conditions. This study examined whether regular physical activity, measured subjectively (Rapid Assessment of Physical Activity [RAPA]) and objectively (Bodymedia's SenseWear® activity monitor [SWA]), is associated with inflammatory or glycemic control markers. METHODS: Subjects were 345 participants of the Healthy Eating and Active Living in the Spirit (HEALS) lifestyle intervention among African American (AA) churches in South Carolina from 2009 to 2012. Linear regression analyses were performed to assess the relationship between both subjectively and objectively measured physical activity and inflammatory markers including high sensitivity C-reactive protein (CRP), interleukin-6 (IL-6), and glycosylated hemoglobin (HbA1c). RESULTS: Those who participated in regular physical activity (from RAPA) had lower CRP values compared to those who were sedentary (2.3 vs. 3.8mg/L, p<0.01). Lower levels of CRP or IL-6 were observed among those in the highest quartile of active energy expenditure (CRP: 2.0 vs. 3.6 mg/L, p=0.01) or moderate-vigorous physical activity minutes (CRP=1.7 vs. 4.5mg/L, p<0.01; IL-6=1.5 vs. 2.1pg/mL, p=0.01) compared to their lowest respective quartiles as measured by the SWA. CONCLUSION: Physical activity may improve chronic inflammation, which is a primary pathophysiological mechanism for numerous chronic disorders, especially among minority populations.

A comparison of a centralized versus de-centralized recruitment schema in two community-based participatory research studies for cancer prevention.

Use of community-based participatory research (CBPR) approaches is increasing with the goal of making more meaningful and impactful advances in eliminating cancer-related health disparities. While many reports have espoused its advantages, few investigations have focused on comparing CBPR-oriented recruitment and retention. Consequently, the purpose of this analysis was to report and compare two different CBPR approaches in two cancer prevention studies. We utilized frequencies and Chi-squared tests to compare and contrast subject recruitment and retention for two studies that incorporated a randomized, controlled intervention design of a dietary and physical activity intervention among African Americans (AA). One study utilized a de-centralized approach to recruitment in which primary responsibility for recruitment was assigned to the general AA community of various church partners whereas the other incorporated a centralized approach to recruitment in which a single lay community individual was hired as research personnel to lead recruitment and intervention delivery. Both studies performed equally well for both recruitment and retention (75 and 88 % recruitment rates and 71 and 66 % retention rates) far exceeding those rates traditionally cited for cancer clinical trials (~5 %). The de-centralized approach to retention appeared to result in statistically greater retention for the control participants compared to the centralized approach (77 vs. 51 %, p < 0.01). Consequently, both CBPR approaches appeared to greatly enhance recruitment and retention rates of AA populations. We further note lessons learned and challenges to consider for future research opportunities.

C-reactive protein levels in African Americans: a diet and lifestyle randomized community trial.

BACKGROUND: Chronic inflammation is linked to poor lifestyle behaviors and a variety of chronic diseases that are prevalent among African Americans, especially in the southeastern U.S. PURPOSE: The goal of the study was to test the effect of a community-based diet, physical activity, and stress reduction intervention conducted in 2009-2012 on reducing serum C-reactive protein (CRP) in overweight and obese African-American adults. METHODS: An RCT intervention was designed jointly by members of African-American churches and academic researchers. In late 2012, regression (i.e., mixed) models were fit that included both intention-to-treat and post hoc analyses conducted to identify important predictors of intervention success. Outcomes were assessed at 3 months and 1 year. RESULTS: At baseline, the 159 individuals who were recruited in 13 churches and had evaluable outcome data were, on average, obese (BMI=33.1 [±7.1]) and had a mean CRP level of 3.7 (±3.9) mg/L. Reductions were observed in waist-to-hip ratio at 3 months (2%, p=0.03) and 1 year (5%, p<0.01). In female participants attending ≥60% of intervention classes, there was a significant decrease in CRP at 3 months of 0.8 mg/L (p=0.05), but no change after 1 year. No differences were noted in BMI or interleukin-6. CONCLUSIONS: In overweight/obese, but otherwise "healthy," African-American church members with very high baseline CRP levels, this intervention produced significant reductions in CRP at 3 and 12 months, and in waist-to-hip ratio, which is an important anthropometric predictor of overall risk of inflammation and downstream health effects. TRIAL REGISTRATION: This study is registered at www.clinicaltrials.gov NCT01760902.