| 1. |
- Lutgendorff, Femke, 1981-, et al.
(författare)
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Probiotics enhance pancreatic glutathione biosynthesis and reduce oxidative stress in experimental acute pancreatitis
- 2008
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Ingår i: American Journal of Physiology - Gastrointestinal and Liver Physiology. - : American Physiological Society. - 0193-1857 .- 1522-1547. ; 295:5
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Tidskriftsartikel (refereegranskat)abstract
- Factors determining severity of acute pancreatitis (AP) are poorly understood. Oxidative stress causes acinar cell injury and contributes to the severity, whereas prophylactic probiotics ameliorate experimental pancreatitis. Our objective was to study how probiotics affect oxidative stress, inflammation, and acinar cell injury during the early phase of AP. Fifty-three male Sprague-Dawley rats were randomly allocated into groups: 1) control, 2) sham procedure, 3) AP with no treatment, 4) AP with probiotics, and 5) AP with placebo. AP was induced under general anesthesia by intraductal glycodeoxycholate infusion (15 mM) and intravenous cerulein (5 μg·kg-1·h-1, for 6 h). Daily probiotics or placebo were administered intragastrically, starting 5 days prior to AP. After cerulein infusion, pancreas samples were collected for analysis including lipid peroxidation, glutathione, glutamate-cysteine-ligase activity, histological grading of pancreatic injury, and NF-κB activation. The severity of pancreatic injury correlated to oxidative damage (r = 0.9) and was ameliorated by probiotics (1.5 vs. placebo 5.5, P = 0.014). AP-induced NF-κB activation was reduced by probiotics (0.20 vs. placebo 0.53 OD 450nm/mg nuclear protein, P < 0.001). Probiotics attenuated AP-induced lipid peroxidation (0.25 vs. placebo 0.51 pmol malondialdehyde/mg protein, P < 0.001). Not only was AP-induced glutathione depletion prevented (8.81 vs. placebo 4.1 μmol/mg protein, P < 0.001), probiotic pretreatment even increased glutathione compared with sham rats (8.81 vs. sham 6.18 μmol/mg protein, P < 0.001). Biosynthesis of glutathione (glutamate-cysteine-ligase activity) was enhanced in probiotic-pretreated animals. Probiotics enhanced the biosynthesis of glutathione, which may have reduced activation of inflammation and acinar cell injury and ameliorated experimental AP, via a reduction in oxidative stress. Copyright © 2008 the American Physiological Society.
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| 2. |
- Lutgendorff, Femke, et al.
(författare)
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Probiotics prevent intestinal barrier dysfunction in acute pancreatitis in rats via induction of ileal mucosal glutathione biosynthesis.
- 2009
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Ingår i: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 4:2, s. e4512-
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 3. |
- Rijkers, Ger T., et al.
(författare)
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Health benefits and health claims of probiotics : bridging science and marketing
- 2011
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Ingår i: British Journal of Nutrition. - 0007-1145 .- 1475-2662. ; 106:9, s. 1291-1296
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Tidskriftsartikel (refereegranskat)abstract
- Health claims for probiotics are evaluated by the Panel on Dietetic Products, Nutrition and Allergies of the European Food Safety Authority. Despite a substantial amount of basic and clinical research on the beneficial effects of probiotics, all of the evaluated claim applications thus far have received a negative opinion. With the restrictions on the use of clinical endpoints, validated biomarkers for gut health and immune health in relation to reduction in disease risk are needed. Clear-cut criteria for design as well as evaluation of future studies are needed. An open dialogue between basic and clinical scientists, regulatory authorities, food and nutrition industry, and consumers could bridge the gap between science and marketing of probiotics.
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| 4. |
- Safari, Dodi, et al.
(författare)
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Gold nanoparticles as carriers for a synthetic Streptococcus pneumoniae type 14 conjugate vaccine
- 2012
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Ingår i: Nanomedicine. - : Future Medicine Ltd. - 1743-5889 .- 1748-6963. ; 7:5, s. 651-662
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Coupling of capsular polysaccharides of pathogens to immunogenic protein carriers (conjugate vaccines) improves carbohydrate immune response. Our idea is to explore gold nanoclusters as carriers to prepare fully synthetic carbohydrate vaccines. Materials & methods: Gold glyconanoparticles bearing a synthetic tetrasaccharide epitope related to the Streptococcus pneumoniae type 14 capsular polysaccharide (Pn14PS), the T-helper ovalbumin 323-339 peptide (OVA(323-339)), and D-glucose were prepared by a one-pot method. Their immunogenicity was tested in mice. Cytokine levels after spleen cell stimulation with OVA(323-339) were analyzed using a luminex-multiplex cytokine assay. The capacity of the evoked antibodies to promote the uptake of S. pneumoniae type 14 by leukocytes was assessed. Results & discussion: Glyconanoparticles containing 45% of tetrasaccharide and 5% OVA(323-339) triggered specific anti-Pn14PS IgG antibodies. Cytokine levels confirmed that glyconanoparticles led to T-helper cell activation. The antisaccharide antibodies promoted the phagocytosis of type 14 bacteria by human leukocytes, indicating the functionality of the antibodies. Conclusion: Gold nanoparticles have great potential as carriers for the development of a great diversity of fully synthetic carbohydrate-based vaccines.
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