Effects of dietary chlorogenic acid on ileal intestinal morphology, barrier function, immune factors and gut microbiota of broilers under high stocking density stress.

Aims: The purpose of this research was to assess the effect of chlorogenic acid (CGA) in the diet on ileac structure, barrier function, immunological state, and microbial profile of broiler chickens in a high stocking density (HD) environment. Methods: Four hundred and seventy-six male AA broiler chickens were randomly split into four groups, two with a normal stocking density (ND) of fourteen birds per m2 and two with a high stocking density of twenty-two birds per m2. Each of the treatments consisted of five replicates. One of the two ND and HD groups received the usual feed, while the other two were given at 1.5 g/kg CGA as part of their dietary regimen. Results: The ND CGA group showed a greater increase in villus height and villus height/crypt depth compared to the ND group at 35 and 42 days. The HD group experienced a greater elevation in villus height due to CGA supplementation than the HD group across days 28, 35, and 42. At day 42, the HD group saw a decline in OCLN and ZO-1 mRNA expression in the ileum, but CGA was able to restore them. The HD group experienced a greater rise in OCLN mRNA than the control HD group when supplemented with CGA. The expression of TNF-α, IL-1ß, and IL-6 in the ileum was higher in the HD group, and CGA supplementation enhanced this effect. The HD group experienced a greater rise in IL-10 mRNA expression than the control group following the administration of CGA. The HD group showed reduced alpha diversity and an increase in detrimental microbes such as Turicibacter and Shigella in the gut compared to the ND group, while the HD CGA group saw a reduction in Turicibacter, Shigella, and other harmful microbes. These findings reveal that HD stress suppressed the growth of ileac villi, decreased the expression of tight-junction genes, amplified the expression of inflammatory genes, and disturbed the gut microbiota, ultimately leading to increased intestinal permeability. Conclusion: We conclude that when chickens are given dietary CGA, the disruption of the ileac barrier and increased oxidative damage and inflammation due to HD stress are reduced, which increases ileac integrity and the presence of beneficial intestinal bacteria.

[Combinatorial CRISPR inversions of CTCF sites in HOXD cluster reveal complex insulator function].

CTCF (CCCTC-binding factor) is a zinc-finger protein which plays a vital role in the three-dimensional (3D) genome architecture. A pair of forward-reverse convergent CTCF binding sites (CBS elements) mediates long-distance DNA interactions to form chromatin loops with the assistance of the cohesin complex, while CBS elements at the chromatin domain boundaries show reverse-forward divergent patterns and function as insulators to discriminate against DNA interaction between chromatin domains. However, there are still many unresolved problems regarding CTCF-mediated insulation function. In order to study the connections between chromatin loops and the insulation function of CBS elements, we combinatorically inverted CBS elements at the HOXD locus by using CRISPR/Cas9 DNA-fragment editing methods in the HEK293T cell line and obtained five different kinds of single-cell CRISPR clones. By performing quantitative high-resolution chromosome conformation capture copy (QHR-4C) experiments, we found that boundary CBS inversions abolish original chromatin loops and establish new loops from the opposite direction, thus shifting the insulator boundary to the new divergent CTCF sites. Furthermore, tandem CBS elements block cohesin permeated from the opposite orientation to function as insulators. RNA-seq experiments showed that alterations of local three-dimensional genome architecture would further influence gene expression of the HOXD cluster. In conclusion, a pair of divergent CBS elements function as insulators by forming chromatin loops within chromatin domains to block cohesin sliding.

Dietary Choline Intake during Pregnancy and PEMT rs7946 Polymorphism on Risk of Preterm Birth: A Case-Control Study.

INTRODUCTION AND AIMS: Choline-metabolizing genetic variation may interact with choline intake on fetal programming and pregnancy outcome. This case-control study aims to explore the association of maternal choline consumption and phosphatidylethanolamine N-methyltransferase (PEMT) gene polymorphism rs7946 with preterm birth risk. METHODS: 145 Han Chinese women with preterm delivery and 157 Han Chinese women with term delivery were recruited in Shanghai. Dietary choline intake during pregnancy was assessed using a validated food frequency questionnaire. Additionally, DNA samples were genotyped for PEMT rs7946 (G5465A) with plasma homocysteine (Hcy) levels measured. RESULTS: Compared with the lowest quartile of choline intake, women within the highest consumption quartile had adjusted odds ratio (aOR) for preterm birth of 0.48 (95% confidence interval, CI [0.24, 0.95]). There was a significant interaction between maternal choline intake and PEMT rs7946 (p for interaction = 0.04), where the AA genotype carriers who consumed the energy-adjusted choline <255.01 mg/day had aOR for preterm birth of 3.75 (95% CI [1.24, 11.35]), compared to those with GG genotype and choline intake >255.01 mg/day during pregnancy. Additionally, the greatest elevated plasma Hcy was found in the cases with AA genotype and choline consumption <255.01 mg/day (p < 0.001). CONCLUSION: The AA genotype of PEMT rs7946 may be associated with increased preterm birth in these Han Chinese women with low choline intake during pregnancy.