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- Lutgendorff, Femke, et al.
(author)
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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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In: PLoS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 4:2, s. e4512-
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Journal article (peer-reviewed)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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| 2. |
- Lutgendorff, Femke, 1981-, et al.
(author)
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Probiotics enhance pancreatic glutathione biosynthesis and reduce oxidative stress in experimental acute pancreatitis
- 2008
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In: American Journal of Physiology - Gastrointestinal and Liver Physiology. - : American Physiological Society. - 0193-1857 .- 1522-1547. ; 295:5
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Journal article (peer-reviewed)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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| 3. |
- Lutgendorff, Femke, et al.
(author)
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Protective Effects of Probiotics on Chronic Stress-Induced Intestinal Permeability in Rats are mediated via Mast Cells and PPARγ
- 2013
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Other publication (other academic/artistic)abstract
- BACKGROUND: Chronic stress, which may affect in the clinical course of inflammatory and functional bowel diseases, disrupts intestinal barrier function by routes involving mast cells. Probiotics have been shown to ameliorate the deleterious effects of stress on intestinal function, but mechanisms remain to be elucidated. Peroxisome proliferator-activated receptor (PPAR)-γ signaling is activated as an endogenous defense mechanism during chronic stress and evidence suggests that probiotics reduce the degradation of PPAR-γ. As a source of the endogenous agonist for PPAR-γ, 15d-PGJ2, and as an important mediator of the stress response, mast cells may have both a beneficial and a deleterious role in the effects on intestinal function by probiotics.AIM: Our aim was to study if mast cells contribute to the positive effects of probiotic therapy on intestinal function in a rat model of chronic stress.METHODS: 32 Mast cell deficient (Ws/Ws) and 32 wild-type (+/+) rats were subjected to water avoidance stress (WAS) or sham stress (SS) 1hr/day for 10 days. Seven days prior to the onset of stress, probiotics (PB, multispecies combination of 10 different lactic acid bacteria) were added to the standard diet (St) in half of the animals. To determine dependence of PPAR-γ, 8 probiotic-fed wild-type rats subjected to WAS were injected daily with the specific PPAR-γ antagonist T0070907. The colonic mucosa was exposed to E. coli HB101 incorporated with green fluorescent protein and permeability was assessed in Ussing chambers. Mesenteric lymph nodes (MLN) were cultured to determine bacterial translocation.RESULTS: Chronic stress induced a marked increase in ileal permeability to E.coli HB101 in +/+ rats (0.17±0.1 x106CFU/hr in SS/St/++ vs. 2.13±0.4 in WAS/St/++; P<0.001). This breach in barrier integrity was less pronounced in Ws/Ws rats (2.13±0.4 in WAS/St/++ vs. 1.19±0.3 in WAS/St/WsWs; P<0.01). Probiotics prevented stress-induced effects in E.coli HB101 passage only in wild-type rats (82% decrease in +/+ vs. 0% in Ws/Ws rats). Furthermore, only in the presence of mast cells did probiotics reduce the enhanced bacterial translocation to MLNs during chronic stress. In wild-type rats treated with a PPAR-γ antagonist, the barrier protective effects of probiotics were diminished.CONCLUSIONS: Mast cells acting via a PPAR-γ dependent pathway contribute to the beneficial effects of probiotics on chronic stress-induced mucosal dysfunction in rats.
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