| 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. |
- Sandström, Per, 1965-, et al.
(författare)
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Serum amino acid profile in patients with acute pancreatitis
- 2008
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Ingår i: Amino Acids. - : Springer Science and Business Media LLC. - 0939-4451 .- 1438-2199. ; 35:1, s. 225-231
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Tidskriftsartikel (refereegranskat)abstract
- Patients in the early phase of acute pancreatitis (AP) have reduced serum levels of arginine and citrulline. This may be of patho-biological importance, since arginine is the substrate for nitric oxide, which in turn is involved in normal pancreatic physiology and in the inflammatory process. Serum amino acid spectrum was measured daily for five days and after recovery six weeks later in 19 patients admitted to the hospital for acute pancreatitis. These patients had abnormal levels of most amino acids including arginine, citrulline, glutamine and glutamate. Phenylalanine and glutamate were increased, while arginine, citrulline, ornithine and glutamine were decreased compared to levels after recovery. NO2/NO3 concentration in the urine, but not serum arginase activity, was significantly increased day 1 compared to day 5 after admission. Acute pancreatitis causes a disturbance of the serum amino acid spectrum, with possible implications for the inflammatory process and organ function both in the pancreas and the gut. Supplementation of selected amino acids could possibly be of value in this severe condition. © 2007 Springer-Verlag.
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| 3. |
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| 4. |
- Trulsson, Lena, 1950-, et al.
(författare)
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Cholecystokinin-8-induced hypoplasia of the rat pancreas : Influence of nitric oxide on cell proliferation and programmed cell death
- 2004
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Ingår i: Basic & Clinical Pharmacology & Toxicology. - 1742-7835 .- 1742-7843. ; 95:4, s. 183-190
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Tidskriftsartikel (refereegranskat)abstract
- The background of cholecystokinin-8 (CCK-8)-induced hypoplasia in the pancreas is not known. In order to increase our understanding we studied the roles of nitric oxide and NF-κB in rats. CCK-8 was injected for 4 days, in a mode known to cause hypoplasia, and the nitric oxide formation was either decreased by means of Nω-nitro-L-arginine (L-NNA) or increased by S-nitroso-N-acetylpencillamine (SNAP). The activation of NF-κB was quantified by ELISA detection, apoptosis with caspase-3 and histone-associated DNA-fragmentation and mitotic activity in the acinar, centroacinar and ductal cells were visualized by the incorporation of [3H]-thymidine. Pancreatic histology and weight as well as protein- and DNA contents were also studied. Intermittent CCK injections reduced pancreatic weight, protein and DNA contents and increased apoptosis, acinar cell proliferation and nuclear factor κB (NF-κB) activation. It also caused vacuolisation of acinar cells. The inhibition of endogenous nitric oxide formation by L-NNA further increased apoptosis and NF-κB activation but blocked the increased proliferation and vacuolisation of acinar cells. The DNA content was not further reduced. SNAP given together with CCK-8 increased apoptosis and other pathways of cell death, raised proliferation of acinar cells and strongly reduced the DNA content in the pancreas. Histological examination showed no inflammation in any group. We conclude that during CCK-8-induced pancreatic hypoplasia, endogenously formed nitric oxide suppresses apoptosis but increases cell death along non-apoptotic pathways and stimulates regeneration of acinar cells. Exogenous nitric oxide enhances the acinar cell turnover by increasing both apoptotic and non-apoptotic cell death and cell renewal. In this situation NF-κB activation seems not to inhibit apoptosis nor promote cell proliferation.
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| 5. |
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| 6. |
- Trulsson, Lena M., 1950-, et al.
(författare)
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Cholecystokinin octapeptide induces both proliferation and apoptosis in the rat pancreas
- 2001
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Ingår i: Regulatory Peptides. - 0167-0115 .- 1873-1686. ; 98:1-2, s. 41-48
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Tidskriftsartikel (refereegranskat)abstract
- Cholecystokinin-8 (CCK-8) causes exocrine pancreatic hypertrophy and hyperplasia. High doses of the CCK analogue cerulein causes necrosis and an inflammatory response in the pancreas. We have studied the pancreatic growth response in rats after administration of CCK-8 for 3 days, given either intermittently (20–80 μg/kg) twice a day, or continuously (2.4–48 μg/kg per 24 h). Plasma CCK-8 levels, pancreatic wet weight, water, protein and DNA contents and the pancreatic caspase-3 activity were measured. Cell proliferation was visualized by [3H]thymidine incorporation and apoptosis by TUNEL reaction. Continuous administration of CCK-8 dose-dependently increased the plasma CCK levels, the pancreatic wet weight, protein and DNA contents as well as thymidine labeling index, apoptotic index and caspase-3 activity. Intermittent injections of CCK-8 caused transient raises in plasma CCK, increased apoptotic index and caspase-3 activity, a dose-dependent increase in thymidine labeling but caused a dose-dependent reduction of pancreatic wet weight, protein, and DNA contents. It is concluded that CCK-8 causes both increased proliferation and apoptosis in the pancreas. In case of continuous administration of CCK-8, the proliferation outweighs the apoptosis causing hyperplasia but in the case of intermittent administration the opposite effect is seen.
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| 7. |
- Trulsson, Lena, 1950-, et al.
(författare)
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Telomerase activity in surgical specimens and fine-needle aspiration biopsies from hyperplastic and neoplastic human thyroid tissues
- 2003
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Ingår i: American Journal of Surgery. - 0002-9610 .- 1879-1883. ; 186:1, s. 83-88
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Tidskriftsartikel (refereegranskat)abstract
- Background: Telomerase activity (TA) indicates malignancy, but activated lymphocytes also express TA. Correlation between TA in thyroid tissues and fine-needle aspiration (FNA) samples and knowledge about TA in adjacent tissue are of importance. Methods: The telomeric repeat amplification protocol assay followed by enzyme-linked immunosorbent assay detection was performed on 78 thyroid cases including 53 suspected malignancies, preoperative and perioperative FNA specimens, and adjacent tissue. Results: Benign lesions in cancer-suspected cases were TA negative. Eight of 13 papillary (62%) and 4 of 5 follicular (80%) tumors were TA positive (TA+). Lower TA was observed in conventional papillary cancer than in follicular, tall cell variant of papillary and anaplastic cancers. Adjacent tissues with lymphocyte infiltration were TA+ in 9 of 17 cases (53%). Nine of 65 adjacent tissues (14%) were TA+. Three of 6 preoperative and 9 of 11 perioperative FNA samples from malignant tumors corresponded to the tissue TA. Conclusions: High TA may reflect more severe thyroid cancer. Telomerase activity in FNA biopsies does not add reliable diagnostic information, and presence of lymphocytes can give false-positive results.
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| 8. |
- Trulsson, Lena, 1950-, et al.
(författare)
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The influence of a load of L-arginine on serum amino acids and pancreatic apoptosis/proliferation and ATP levels in the rat
- 2004
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Ingår i: Pancreas. - 0885-3177 .- 1536-4828. ; 29:4, s. 113-120
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES:Administration of high doses of amino acids like ethionine, methionine, and arginine causes pancreatic tissue damage. The initial mechanism behind these effects is not known. The aim of this study was to show the early effects of a load of L-arginine on programed cell death/proliferation and ATP levels in the pancreas.METHODS:We analyzed in rats the effects of intraperitoneal administration of L-arginine on serum amino acids, pancreatic cell apoptosis/proliferation, and ATP levels at 8, 16, and 24 hours. Serum amino acid concentrations were measured with HPLC, tissue ATP was measured fluorometrically, apoptosis was studied with caspase-3 activity and histone-associated DNA-fragments, and proliferation was studied with thymidine autoradiography.RESULTS:After a load of l-arginine, there were initially increased serum levels of L-arginine and L-citrulline, but these fell below control levels after 24 hours as well as amino acids in the glutamate family (ornithine, proline, histidine, and glutamine). Initially, increased ATP levels in the pancreatic tissue returned to control levels at 24 hours. The acinar cells proliferation was suppressed and the apoptosis rate strongly increased at 16 and 24 hours. Pancreatic histology showed vacuole formation in the acinar cells at 8 hours. At 16 hours, there was less vacuolization, but apoptotic bodies were seen, and at 24 hours there was cell degeneration but no necrosis.CONCLUSIONS:After a load of l-arginine, amino acid metabolism causes a high ATP production in the pancreatic tissue that may cause mitochondrial initiation of cell death.
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| 9. |
- Trulsson, Lena, 1950-
(författare)
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The influence of nitric oxide and cholecystokinin on tissue homeostasis in exocrine pancreas : an experimental study in rats
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Growth of the pancreas is stimulated by cholecystokinin (CCK) in rats. Nitric oxide (NO), which is synthesized from the amino acid L-arginine by NO-synthases (NOS), interferes with CCK in modulating the pancreatic secretion. Both pro- and anti-apoptotic influences of NO have been observed in other tissues, but its importance for pancreatic tissue homeostasis has not been studied.Cell proliferation and death rates were studied in the rat pancreas during different experimental conditions. CCK-octapeptide (CCK-8) was given in different doses either intermittently or continuously for three days and the pancreatic growth response was studied. Exogenous CCK-8 caused dose-dependent pancreatic atrophy when given intermittently and hyperplasia when given continuously.The influence of NO on cell death and proliferation was studied during: 1) basal conditions, 2) CCK-8 induced hyperplasia, and 3) CCK-8 induced atrophy. The NO level was manipulated either by NOS inhibition (L-NNA) or by exogenous NO supply (SNAP). NO-metabolism was assessed in the basal situation by analysis of nitrite/nitrate excretion in urine (which was decreased by L-NNA and increased by SNAP), and L-arginine in serum (which increased by L-NNA) and L-citrulline in serum.1) During basal conditions NOS inhibition (NO↓) increased apoptosis and decreased cell proliferation.2) During CCK-8 induced hyperplasia NOS inhibition (NO↓) increased both apoptosis and cell proliferation. The apoptosis dominated as indicated by decreased DNA content. SNAP administration (NO↑) did neither influence apoptosis nor cell proliferation.3) During CCK-8 induced atrophy (DNA↓, apoptosis↑, cell proliferation↑, and cytoplasmic vacuolization) NOS inhibition further increased apoptosis, reduced cell proliferation and abolished vacuole formation. SNAP administration (NO↑) decreased the DNA content, and increased both apoptosis and cell proliferation. The vacuole formation was still present. Hence, NO influences both the basal and the disturbed homeostasis in hyperplastic and atrophic rat pancreatic tissue.Early events of a load of L-arginine, known to induce pancreatitis within 48 hrs, was studied at 8, 16 and 24 hrs by analysis of serum L-arginine and L-citrulline, pancreatic tissue ATP, apoptosis and cell proliferation. The initially increased serum L-arginine and L-citrulline decreased to levels below control at 24 hrs. Administration of L-arginine was correlated to a biphasic ATP production and formation of small vacuoles (mitochondrial swelling) in the acinar cells, most prominent at 8 hrs and followed by a gradually increased apoptosis rate. The cell proliferation decreased. At 24 hrs there was pronounced cell degeneration, but no evident necrosis. Another 20 amino acids in serum were also analysed at 24 hrs. Twelve amino acids (including the 'glutamate family') were significantly reduced. After an L-arginine load the augmented A TP production correlates to the initiation of pancreatic cell death. The disturbed amino acid metabolism seems to be of importance for development of experimental pancreatitis.
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| 10. |
- Trulsson, Lena, 1950-, et al.
(författare)
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The influence of nitric oxide on basal and cholecystokinin-8-induced proliferation and apoptosis in the rat pancreas
- 2002
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Ingår i: Regulatory Peptides. - 0167-0115 .- 1873-1686. ; 106:1-3, s. 97-104
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Tidskriftsartikel (refereegranskat)abstract
- Nitric oxide (NO) is formed by different cell types in the pancreas. In this study, inhibition of endogenous nitric oxide by Nω-nitro-l-arginine (l-NNA) reduced the urinary excretion of NO2/NO3 and raised serum l-arginine and the NO donator S-nitroso-N-acetylpenicillamine (SNAP) increased the urinary excretion of NO2/NO3. The peptide cholecystokinin-8 (CCK-8) has a strong influence on exocrine pancreatic proliferation. Rat pancreas was excised and studied with regard to tissue weight, protein and DNA contents after 3 days of treatment with saline, l-NNA or SNAP given separately or combined with CCK-8. Further, proliferation of different pancreatic cells was studied with [3H]-thymidine incorporation and apoptotic activity was studied by analysing caspase-3 activity and histone-associated DNA fragments. The effects of l-NNA indicate that endogenous nitric oxide formation has a tonic inhibition on apoptosis in the pancreas during both basal condition and growth stimulation by CCK-8. In CCK-induced hyperplasia, NO inhibits the proliferation of acinar cells but stimulates ductal cells. Endogenous NO may regulate the balance between proliferation and apoptosis and in a situation of growth stimulation by CCK-8, it has a tonic inhibition on both mitogenesis and apoptosis thus slowing down the acinar cell turnover in the pancreas.
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