Primary biliary cirrhosis (PBC) is a chronic cholestatic liver condition characterized by the immune-mediated damage of the intrahepatic bile ducts. Polymorphisms of vitamin D receptor (VDR) are considered to contribute to its pathogenesis however their incidence varies in different populations and their potential association with the course of the disease has not been studied. In this paper we investigated the incidence and correlation of three VDR polymorphisms (BsmI, ApaI or TaqI) with various clinical, biochemical, and serological factors in a homogenous group of 143 Caucasian patients with PBC. Control group comprises 306 DNA samples from umbilical cord blood of healthy newborn children. When compared to controls, we observed a significant dominance of the b allele in the BsmI (OR = 1.69 [1.27–2.24]; P = 0.0003) and t allele in the TaqI (OR = 0.62 [0.47–0.82], P = 0.0001) in patients with PBC. Moreover the BsmI and TaqI polymorphisms were associated with the presence of advanced fibrosis/liver cirrhosis at the diagnosis of PBC. Pairwise linkage disequilibrium (LD) calculations proved that the analyzed SNPs are within an LD block (100% of LDs were D'>0.9). Our study showed, for the first time, that the analyzed polymorphisms of VRD may exert an effect on a natural history of PBC.

Background/Aims: The common G22A polymorphism in the adenosine deaminase (ADA) gene leads to substitution Asp8Asn. The lower activity of the enzyme encoded by A22 (ADA*2) allele may increase tissue concentrations of adenosine, a potent cardioprotective agent. In a case-control study, we investigated the association between ADA polymorphism and coronary artery disease (CAD). Methods: A hundred and seventy-one CAD patients from the north-western part of Poland and 200 consecutive newborns from the same population were genotyped by PCR-RFLP. Results: Twenty-five ADA*1/*2 heterozygotes (12.5%) and 2 ADA*2/*2 homozygotes (1%) were found in the control group, while only 10 *1/*2 heterozygotes (5.9%) and no *2/*2 homozygotes were found in the CAD group. Frequencies of ADA*2 carriers (5.9% vs. 13.5%, p = 0.015) and ADA*2 allele (2.9% vs. 7.3%, p = 0.0083) were lower in CAD patients than in controls. Among CAD patients, a significantly lower proportion of *2 allele carriers was treated with diuretics and ACE inhibitors when compared to *1/*1 wild-type homozygotes. Conclusion: ADA*2 allele may decrease genetic susceptibility to CAD. ADA should be added to the list of candidate genes modifying the risk of cardiovascular diseases.

Background: It can be hypothetically assumed that maternal and perinatal factors influence the intestinal barrier. Methods: The study was conducted with 100 healthy, full-term newborns breastfed in the first week of life, with similar analyses for their mothers. Zonulin and calprotectin levels were used as intestinal permeability markers. Results: The median (range) zonulin concentrations (ng/mL) were in mothers: serum, 21.39 (6.39–57.54); stool, 82.23 (42.52–225.74); and newborns: serum cord blood, 11.14 (5.82–52.34); meconium, 54.15 (1.36–700.65); and stool at age seven days, 114.41 (29.38–593.72). Calprotectin median (range) concentrations (µg/mL) in mothers were: stool, 74.79 (3.89–211.77); and newborns: meconium, 154.76 (6.93–8884.11); and stool at age seven days 139.12 (11.89–627.35). The use of antibiotics during pregnancy resulted in higher zonulin concentrations in umbilical-cord serum and calprotectin concentrations in newborn stool at seven days, while antibiotic therapy during labour resulted in higher zonulin concentrations in the stool of newborns at seven days. Zonulin concentrations in the stool of newborns (at seven days) who were born via caesarean section were higher compared to with vaginal birth. With further analyses, caesarean section was found to have a greater effect on zonulin concentrations than prophylactic administration of antibiotics in the perinatal period. Pregnancy mass gain >18 kg was associated with higher calprotectin concentrations in maternal stool. Body Mass Index (BMI) increase >5.7 during pregnancy was associated with decreased zonulin concentrations in maternal stool and increased calprotectin concentrations in stool of mothers and newborns at seven days. There was also a negative correlation between higher BMI increase in pregnancy and maternal zonulin stool concentrations and a positive correlation between BMI increase in pregnancy and maternal calprotectin stool concentrations. Conclusion: Maternal-foetal factors such as caesarean section, antibiotic therapy during pregnancy, as well as change in mother’s BMI during pregnancy may increase intestinal permeability in newborns. Changes in body mass during pregnancy can also affect intestinal permeability in mothers. However, health consequences associated with increased intestinal permeability during the first days of life are unknown. Additionally, before the zonulin and calprotectin tests can be adopted as universal diagnostic applications to assess increased intestinal permeability, validation of these tests is necessary.

Background The intestinal barrier plays an important role in the defense against infections, and nutritional, endocrine, and immune functions. The gut microbiota playing an important role in development of the gastrointestinal tract can impact intestinal permeability and immunity during early life, but data concerning this problem are scarce. Methods We analyzed the microbiota in fecal samples (101 samples in total) collected longitudinally over 24 months from 21 newborns to investigate whether the markers of small intestinal paracellular permeability (zonulin) and immune system development (calprotectin) are linked to the gut microbiota. The results were validated using data from an independent cohort that included the calprotectin and gut microbiota in children during the first year of life. Results Zonulin levels tended to increase for up to 6 months after childbirth and stabilize thereafter remaining at a high level while calprotectin concentration was high after childbirth and began to decline from 6 months of life. The gut microbiota composition and the related metabolic potentials changed during the first 2 years of life and were correlated with zonulin and calprotectin levels. Faecal calprotectin correlated inversely with alpha diversity (Shannon index, r = − 0.30, FDR P (Q) = 0.039). It also correlated with seven taxa; i.a. negatively with Ruminococcaceae (r = − 0.34, Q = 0.046), and Clostridiales (r = − 0.34, Q = 0.048) and positively with Staphylococcus (r = 0.38, Q = 0.023) and Staphylococcaceae (r = 0.35, Q = 0.04), whereas zonulin correlated with 19 taxa; i.a. with Bacillales (r = − 0.52, Q = 0.0004), Clostridiales (r = 0.48, Q = 0.001) and the Ruminococcus (torques group) (r = 0.40, Q = 0.026). When time intervals were considered only changes in abundance of the Ruminococcus (torques group) were associated with changes in calprotectin (β = 2.94, SE = 0.8, Q = 0.015). The dynamics of stool calprotectin was negatively associated with changes in two MetaCyc pathways: pyruvate fermentation to butanoate (β = − 4.54, SE = 1.08, Q = 0.028) and Clostridium acetobutylicum fermentation (β = − 4.48, SE = 1.16, Q = 0.026). Conclusions The small intestinal paracellular permeability, immune system-related markers and gut microbiota change dynamically during the first 2 years of life. The Ruminococcus (torques group) seems to be especially involved in controlling paracellular permeability. Staphylococcus, Staphylococcaceae, Ruminococcaceae, and Clostridiales, may be potential biomarkers of the immune system. Despite observed correlations their clear causation and health consequences were not proven. Mechanistic studies are required. Graphic abstract

Over the last decade, remarkable progress has been made in the understanding of disease pathophysiology. Many new theories expound on the importance of emerging factors such as microbiome influences, genomics/omics, stem cells, innate intestinal immunity or mucosal barrier complexities. This has introduced a further dimension of uncertainty into clinical decision-making, but equally, may shed some light on less well-understood and difficult to manage conditions. Areas covered: Comprehensive review of the literature on gut barrier and microbiome relevant to small bowel pathology. A PubMed/Medline search from 1990 to April 2017 was undertaken and papers from this range were included. Expert commentary: The scenario of clinical uncertainty is well-illustrated by functional gastrointestinal disorders (FGIDs). The movement towards achieving a better understanding of FGIDs is expressed in the Rome IV guidelines. Novel diagnostic and therapeutic protocols focused on the GB and SB microbiome can facilitate diagnosis, management and improve our understanding of the underlying pathological mechanisms in FGIDs.