Gut microbiota changes correlate with health status. Literature data on gut microbiota show that all dietary changes can induce the alteration of gut microbiota composition. Mediterranean diet (MD) is associated with a reduction of all-cause mortality and in this review, we analyzed its interactions with human microbiota. In particular, we explored the modulation of the human microbiota, in response to MD adherence, focusing the attention on polyphenols, polyunsaturated fatty acids (PUFA) ω-3 and fiber. Evidences suggest that MD is able to modulate the gut microbiota, increasing its diversity. In fact, a Mediterranean-type dietary pattern is associated with specific gut microbiota characteristics. The available evidence, suggests that gut microbiota of subjects that follow a MD is significantly different from subjects that follow a Western diet model. In fact, the latter show an increased gut permeability, which is responsible for metabolic endotoxemia. For this reason, we can speculate that the gut microbiota of the subjects following a MD is able to prevent the onset of chronic non-communicable degenerative diseases, such as cardiovascular diseases and some types of cancer. However, in order to understand these correlations with dietary patterns, controlled intervention studies on the gut microbiota composition and activity are needed.

Aluated by the 51Cr-ethylenediaminetetraacetic acid (51Cr-EDTA) permeability test in 52 LC patients and in 48 sex- and age-matched controls. The presence of 51Cr-EDTA was also evaluated in ascitic fluid after therapeutic paracentesis in all LC patients with ascites. RESULTS: An altered IP was found in 45% of LC patients compared with 4% of controls (P<0.00001). IP impairment was significantly associated with Child–Pugh status (75% of Child C patients vs. 39% of Child B and 22% of Child A patients), with the presence of ascites (60% in ascitic patients vs. 31% in nonascitic patients), and with a history of SBP (100% of patients with SBP vs. 50% of those without SBP). 51Cr-EDTA was present in all ascitic samples obtained from patients with SBP compared with 22% of patients without SBP. CONCLUSIONS: IP derangement was a common finding in LC, especially in patients with more advanced disease (presence of ascites and history of SBP). The presence of 51Cr-EDTA in ascites in patients with SBP suggests an altered permeability of splancnic vessels and/or peritoneal membranes. Further studies are required to assess 51Cr-EDTA urine and ascite cutoffs to set up SBP preventive strategies....

Summary: Background: Rifaximin is a broad spectrum non‐absorbable antibiotic used for treatment of small intestinal bacterial overgrowth. Doses of 1200 mg/day showed a decontamination rate of 60% with low side‐effects incidence.Aims: To assess efficacy, safety and tolerability of rifaximin 1600 mg with respect to 1200 mg/day for small intestinal bacterial overgrowth treatment.Methods: Eighty consecutive small intestinal bacterial overgrowth patients were enrolled. Diagnosis of small intestinal bacterial overgrowth based the clinical history and positivity to H₂/CH₄ glucose breath test. Patients were randomized in two 7‐day treatment groups: rifaximin 1600 mg (group 1); rifaximin 1200 mg (group 2). Glucose breath test was reassessed 1 month after. Compliance and side‐effect incidence were also evaluated.Results: One drop‐out was observed in group 1 and two in group 2. Glucose breath test normalization rate was significantly higher in group 1 with respect to group 2 both in intention‐to‐treat (80% vs. 58%; P < 0.05) and per protocol analysis (82% vs. 61%; P < 0.05). No significant differences in patient compliance and incidence of side effects were found between groups.Conclusions: Rifaximin 1600 mg/day showed a significantly higher efficacy for small intestinal bacterial overgrowth treatment with respect to 1200 mg with similar compliance and side‐effect profile.

Cytotoxic associated gene-A (CagA)-positive strains of Helicobacter pylori emerged as a possible atherosclerotic stimulus. Nevertheless, whether CagA-positivity is associated with more extensive or severe atherosclerotic coronary burden has never been studied. Forty consecutive patients with coronary artery disease (CAD) and twenty consecutive patients with normal coronary arteries undergoing coronary angiography were enrolled. All patients underwent evaluation of classical atherogenic risk factors and assessment of anti-urease B and anti-CagA antibodies titer. Either the severity of coronary stenosis (stenosis score) or the extent of coronary atherosclerosis (extent score) was evaluated in CAD patients. The anti-CagA antibody titer was significantly higher in patients with CAD as compared with normal coronary arteries patients [85 (10–108.75) vs. 47.3 (17–64) RU/ml, P=0.02], whereas there were no differences in anti-urease B titer between the two groups. A significant correlation was found between anti-CagA antibody titer and extent score (R=0.35, P=0.03), whereas stenosis score was similar (R=0.25, P=0.11). On the contrary, no significant correlation was found between anti-urease B antibody titer and either extent or stenosis score. Moreover, CagA-positive patients had a more extensive CAD (P=0.029) when compared with CagA-negative patients. Interestingly, whereas serum glucose, LDL levels, anti-urease B, and anti-CagA antibodies were predictors of extent score at univariate analysis, at multivariate analysis anti-CagA antibody titer only was an independent predictor of the extent of coronary atherosclerosis (B=0.051, standard error of B=0.042, P=0.04). These results support the association between CagA-positive H. pylori infection and coronary atherosclerotic burden. Further studies are needed to better elucidate the mechanism by which CagA-positive strains may promote atherosclerosis.

The human gastrointestinal tract hosts a complex and dynamic population of commensal bacterial species, which have coevolved with the host, generating a symbiotic relationship. Some compounds present in foods, such as polyols, prebiotic fibers, or phenolic compounds, are poorly metabolized and absorbed by the host before the transformation guided by the colonic microbiota. By influencing gut microbiota, diet plays a fundamental role in understanding the beneficial effects of the gut microbiota on the host, including its long-term metabolism. The idea that probiotics can act not only by influencing the colonizing microbiota opens the door to a wider range of probiotic possibilities, encouraging innovation in the field. Furthermore, it has been shown both that some probiotics increase phagocytosis or the activity of natural killer cells. Current prebiotics are mainly based on carbohydrates, but other substances, such as polyphenols and polyunsaturated fatty acids, could exert prebiotic effects. A prebiotic substance has been defined as ‘a substrate that is selectively used by host microorganisms that confer a health benefit’, and so can interact with the gut microbiota through competition for nutrients, antagonism, cross-feeding, and support for microbiota stability. Influencing its composition in terms of richness and diversity, food components have a key impact on the intestinal microbiota. Eating habits can strongly influence the composition of the intestinal microbiota. A healthy intestinal microbiota is essential for maintaining general health, and diet is one of the major modulators of this fascinating world of microorganisms. This must give us one more reason to adopt a healthy lifestyle.

Background: Evidence of probiotics effects on gut function, brain activity and emotional behaviour were provided. Probiotics can have dramatic effects on behaviour through the microbiome–gut–brain axis, through vagus nerve. We investigated whether chronic probiotic intake could modulate psychological state, eating behaviour and body composition of normal weight obese (NWO) and preobese–obese (PreOB/OB) compared to normal weight lean women (NWL). Methods: 60 women were enrolled. At baseline and after a 3-week probiotic oral suspension (POS) intake, all subjects underwent evaluation of body composition by anthropometry and dual X-ray absorptiometry, and psychological profile assessment by self-report questionnaires (i.e. EDI-2, SCL90R and BUT). Statistical analysis was carried out using paired t test or a non-parametric Wilcoxon test to evaluate differences between baseline and after POS intake, one-way ANOVA to compare all three groups and, where applicable, Chi square or t test were used to assess symptoms. Results: Of the 48 women that concluded the study, 24% were NWO, 26% were NWL and 50% were PreOB/OB. Significant differences in body composition were highlighted among groups both at baseline and after a POS (p < 0.05). After POS intake, a significant reduction of BMI, resistance, FM (kg and %) (p < 0.05), and a significant increase of FFM (kg and %) (p < 0.05) were observed in all subjects in NOW and PreOB/OB. After POS intake, reduction of bacterial overgrowth syndrome (p < 0.05) and lower psychopathological scores (p < 0.05) were observed in NWO and PreOB/OB women. At baseline and after POS intake, all subjects tested were negative to SCL90R_GSI scale, but after treatment subjects positive to BUT_GSI scale were significantly reduced (8.33%) (p < 0.05) compared to the baseline (33.30%). In NWO and PreOB/OB groups significant differences (p < 0.05) in response to the subscales of the EDI-2 were observed. Significant improvement of the orocecal transit time was observed (p < 0.05) after POS intake. Furthermore, significant differences were observed for meteorism (p < 0.05) and defecation frequency (p < 0.05). Conclusions: A 3-week intake of selected psychobiotics modulated body composition, bacterial contamination, psychopathological scores of NWO and PreOB/OB women. Further research is needed on a larger population and for a longer period of treatment before definitive conclusions can be made. Trial registration ClinicalTrials.gov Id: NCT01890070