Association between probiotics and enteral nutrition in an experimental acute pancreatitis model in rats.

BACKGROUND/OBJECTIVES: Recently, a randomized controlled trial showed that probiotic prophylaxis was associated with an increased mortality in enterally fed patients with predicted severe pancreatitis. In a rat model for acute pancreatitis, we investigated whether an association between probiotic prophylaxis and enteral nutrition contributed to the higher mortality rate. METHODS: Male Sprague-Dawley rats were allocated to four groups: 1) acute pancreatitis (n = 9), 2) acute pancreatitis and probiotic prophylaxis (n = 10), 3) acute pancreatitis and enteral nutrition (n = 10), and 4) acute pancreatitis, probiotic prophylaxis and enteral nutrition (n = 11). Acute pancreatitis was induced by intraductal glycodeoxycholate and intravenous cerulein infusion. Enteral nutrition, saline, probiotics and placebo were administered through a permanent jejunal feeding. Probiotics or placebo were administered starting 4 days before induction of pancreatitis and enteral nutrition 1 day before start until the end of the experiment, 6 days after induction of pancreatitis. Tissue samples and body fluids were collected for microbiological and histological examination. RESULTS: In all animals, serum amylase was increased six hours after induction of pancreatitis. After fulfilling the experiment, no differences between groups were found in histological severity of pancreatitis, degree of discomfort, weight loss, histological examination of small bowel and bacterial translocation (all p > 0.05). Overall mortality was 10% without differences between groups (p = 0.54). CONCLUSION: No negative association was found between prophylactic probiotics and enteral nutrition in acute pancreatitis. No new clues for a potential mechanism responsible for the higher mortality and bowel ischaemia in the PROPATRIA study were found.

Correlation between protection against sepsis by probiotic therapy and stimulation of a novel bacterial phylotype.

Prophylactic probiotic therapy has shown beneficial effects in an experimental rat model for acute pancreatitis on the health status of the animals. Mechanisms by which probiotic therapy interferes with severity of acute pancreatitis and associated sepsis, however, are poorly understood. The aims of this study were to identify the probiotic-induced changes in the gut microbiota and to correlate these changes to disease outcome. Duodenum and ileum samples were obtained from healthy and diseased rats subjected to pancreatitis for 7 days and prophylactically treated with either a multispecies probiotic mixture or a placebo. Intestinal microbiota was characterized by terminal-restriction fragment length polymorphism (T-RFLP) analyses of PCR-amplified 16S rRNA gene fragments. These analyses showed that during acute pancreatitis the host-specific ileal microbiota was replaced by an "acute pancreatitis-associated microbiota." This replacement was not reversed by administration of the probiotic mixture. An increase, however, was observed in the relative abundance of a novel bacterial phylotype most closely related to Clostridium lituseburense and referred to as commensal rat ileum bacterium (CRIB). Specific primers targeting the CRIB 16S rRNA gene sequence were developed to detect this phylotype by quantitative PCR. An ileal abundance of CRIB 16S rRNA genes of more than 7.5% of the total bacterial 16S rRNA gene pool was correlated with reduced duodenal bacterial overgrowth, reduced bacterial translocation to remote organs, improved pancreas pathology, and reduced proinflammatory cytokine levels in plasma. Our current findings and future studies involving this uncharacterized bacterial phylotype will contribute to unraveling one of the potential mechanisms of probiotic therapy.

Increased consumption of fatty and lean fish reduces serum C-reactive protein concentrations but not inflammation markers in feces and in colonic biopsies.

Fish consumption is associated with a reduced colorectal cancer risk. A possible mechanism by which fish consumption could decrease colorectal cancer risk is by reducing inflammation. However, thus far, intervention studies investigating both systemic and local gut inflammation markers are lacking. Our objective in this study was to investigate the effects of fatty and lean fish consumption on inflammation markers in serum, feces, and gut. In an intervention study, participants were randomly allocated to receive dietary advice (DA) plus either 300 g of fatty fish (salmon) or 300 g of lean fish (cod) per week for 6 mo, or only DA. Serum C-reactive protein (CRP) concentrations were measured pre- and postintervention (n = 161). In a subgroup (n = 52), we explored the effects of the fish intervention on fecal calprotectin and a wide range of cytokines and chemokines in fecal water and in colonic biopsies. Serum CRP concentrations were lower in the salmon (-0.5 mg/L; 95% CI -0.9, -0.2) and cod (-0.4 mg/L; 95% CI -0.7, 0.0) groups compared with the DA group. None of the inflammation markers in fecal water and colonic biopsies differed between the DA group and the groups that consumed extra fish. In conclusion, increasing salmon or cod consumption for 6 mo resulted in lower concentrations of the systemic inflammation marker CRP. However, exploratory analysis of local markers of inflammation in the colon or feces did not reveal an effect of fish consumption.

Probiotics prevent intestinal barrier dysfunction in acute pancreatitis in rats via induction of ileal mucosal glutathione biosynthesis.

BACKGROUND: During acute pancreatitis (AP), oxidative stress contributes to intestinal barrier failure. We studied actions of multispecies probiotics on barrier dysfunction and oxidative stress in experimental AP. METHODOLOGY/PRINCIPAL FINDINGS: Fifty-three male Spraque-Dawley rats were randomly allocated into five groups: 1) controls, non-operated, 2) sham-operated, 3) AP, 4) AP and probiotics and 5) AP and placebo. AP was induced by intraductal glycodeoxycholate infusion and intravenous cerulein (6 h). Daily probiotics or placebo were administered intragastrically, starting five days prior to AP. After cerulein infusion, ileal mucosa was collected for measurements of E. coli K12 and (51)Cr-EDTA passage in Ussing chambers. Tight junction proteins were investigated by confocal immunofluorescence imaging. Ileal mucosal apoptosis, lipid peroxidation, and glutathione levels were determined and glutamate-cysteine-ligase activity and expression were quantified. AP-induced barrier dysfunction was characterized by epithelial cell apoptosis and alterations of tight junction proteins (i.e. disruption of occludin and claudin-1 and up-regulation of claudin-2) and correlated with lipid peroxidation (r>0.8). Probiotic pre-treatment diminished the AP-induced increase in E. coli passage (probiotics 57.4+/-33.5 vs. placebo 223.7+/-93.7 a.u.; P<0.001), (51)Cr-EDTA flux (16.7+/-10.1 vs. 32.1+/-10.0 cm/s10(-6); P<0.005), apoptosis, lipid peroxidation (0.42+/-0.13 vs. 1.62+/-0.53 pmol MDA/mg protein; P<0.001), and prevented tight junction protein disruption. AP-induced decline in glutathione was not only prevented (14.33+/-1.47 vs. 8.82+/-1.30 nmol/mg protein, P<0.001), but probiotics even increased mucosal glutathione compared with sham rats (14.33+/-1.47 vs. 10.70+/-1.74 nmol/mg protein, P<0.001). Glutamate-cysteine-ligase activity, which is rate-limiting in glutathione biosynthesis, was enhanced in probiotic pre-treated animals (probiotics 2.88+/-1.21 vs. placebo 1.94+/-0.55 nmol/min/mg protein; P<0.05) coinciding with an increase in mRNA expression of glutamate-cysteine-ligase catalytic (GCLc) and modifier (GCLm) subunits. CONCLUSIONS: Probiotic pre-treatment diminished AP-induced intestinal barrier dysfunction and prevented oxidative stress via mechanisms mainly involving mucosal glutathione biosynthesis.

Nutritional support for the infant's immune system.

Newborn babies possess a functional but immature immune system as a defense against a world teeming with microorganisms. Breast milk contains a number of biological, active compounds that support the infant's immune system. These include secretory immunoglobulin A (IgA), which confers specific protection against enteric pathogens, as well as numerous other immunological, active ingredients. A number of these ingredients can be used as supplements for infant formulas based on cow's milk. Here, the strength of evidence regarding the immune-stimulating effects of selected minerals, vitamins, fatty acids, pre- and probiotics, and nucleotides is reviewed. An assessment of how these ingredients are used in infant-formula products currently available on the market is also presented.

Pneumococcal conjugate vaccination in children with recurrent acute otitis media: a therapeutic alternative?

BACKGROUND: Based on two clinical trials in healthy infants the American Academy of Pediatrics (AAP) advices immunization with a 7-valent pneumococcal conjugate vaccine in children with recurrent acute otitis media (AOM). OBJECTIVE: To study the efficacy of a 7-valent pneumococcal conjugate vaccine on acute otitis media recurrences, its immunogenicity and impact on nasopharyngeal Streptococcus pneumoniae carriage in children with a history of frequent acute otitis media. METHODS: In this double-blind, randomized study, 74 Belgian children, aged 1-7 years, with at least 2 clinically diagnosed episodes of acute otitis media in the previous year were enrolled. Children were immunized with either a 7-valent pneumococcal conjugate vaccine followed by a 23-valent pneumococcal polysaccharide booster or a control hepatitis A vaccine. Total follow-up was 26 months. RESULTS: Despite adequate serum IgG responses to all conjugate vaccine pneumococcal serotypes, no reduction of acute otitis media episodes was observed in the pneumococcal vaccine group as compared to the control group (rate ratio: 1.16; 95% CI: 0.69-1.96). Overall nasopharyngeal pneumococcal carriage remained stable. However, a transient shift from conjugate vaccine related S. pneumoniae serogroups to non-vaccine related serogroups was noted following conjugate vaccination. CONCLUSION: Clinically no protective effect of pneumococcal conjugate vaccination on acute otitis media recurrences was found in children with a history of frequent AOM.