The Experts below are selected from a list of 18501 Experts worldwide ranked by ideXlab platform
Per-olof Hasselgren - One of the best experts on this subject based on the ideXlab platform.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Guang Jo Luo, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-kappaB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1beta-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1beta. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)alpha. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-κB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1β-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1β. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)α. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications. © 2003 Wiley-Liss, Inc.
-
interleukin 1β induces complement component c3 and il 6 production at the basolateral and apical membranes in a human intestinal epithelial cell line
Shock, 2000Co-Authors: M R Moon, Alexander A. Parikh, Josef E. Fischer, Christine D Kane, Andrew L. Salzman, Timothy A Pritts, Per-olof HasselgrenAbstract:: In previous studies, stimulation of cultured Enterocytes with IL-1beta resulted in production of IL-6 and complement component C3. The cellular mechanisms of these responses in the enterocyte are not fully understood. We tested the hypothesis that IL-1beta-induced C3 and IL-6 production is differentially regulated at the apical and basolateral membranes of the enterocyte. Caco-2 cells (a transformed human colonic carcinoma cell line) were grown in a 2-chamber system to full differentiation. The cells were treated with IL-1beta either at the apical or basolateral membrane, and C3 and IL-6 mRNA levels and release of C3 and IL-6 into the apical and basal chambers were determined. The release of C3 was greatest into the basal chamber regardless of whether the cells were stimulated at the apical or basolateral membrane. In contrast, the production of IL-6 was greatest at the cell membrane that was stimulated with IL-1beta. Stimulation of the Caco-2 cells with IL-1beta resulted in increased mRNA levels for C3 and IL-6 with no major differences noted when the cells were treated at the apical or basolateral membrane. The results suggest that enterocyte production and release of at least some acute phase proteins and cytokines are differentially regulated at the apical and basolateral membrane of the enterocyte after stimulation with IL-1beta.
-
interleukin 1β induces complement component c3 and il 6 production at the basolateral and apical membranes in a human intestinal epithelial cell line
Surgical Infection Society. Annual Meeting, 2000Co-Authors: M R Moon, Alexander A. Parikh, Josef E. Fischer, Christine D Kane, Andrew L. Salzman, Timothy A Pritts, Per-olof HasselgrenAbstract:In previous studies, stimulation of cultured Enterocytes with IL-1 β resulted in production of IL-6 and complement component C3. The cellular mechanisms of these responses in the enterocyte are not fully understood. We tested the hypothesis that IL-1β-induced C3 and IL-6 production is differentially regulated at the apical and basolateral membranes of the enterocyte. Caco-2 cells (a transformed human colonic carcinoma cell line) were grown in a 2-chamber system to full differentiation. The cells were treated with IL-1 β either at the apical or basolateral membrane, and C3 and IL-6 mRNA levels and release of C3 and IL-6 into the apical and basal chambers were determined. The release of C3 was greatest into the basal chamber regardless of whether the cells were stimulated at the apical or basolateral membrane. In contrast, the production of IL-6 was greatest at the cell membrane that was stimulated with IL-1β. Stimulation of the Caco-2 cells with IL-1β resulted in increased mRNA levels for C3 and IL-6 with no major differences noted when the cells were treated at the apical or basolateral membrane. The results suggest that enterocyte production and release of at least some acute phase proteins and cytokines are differentially regulated at the apical and basolateral membrane of the enterocyte after stimulation with IL-1β.
-
sepsis increases putrescine concentration and protein synthesis in mucosa of small intestine in rats
Shock, 1996Co-Authors: Yoshifumi Noguchi, Tory A Meyer, Greg Tiao, Josef E. Fischer, Per-olof HasselgrenAbstract:ABSTRACT— Recent studies suggest that sepsis stimulates mucosal polyamine and protein synthesis. It is not known in which cell type polyamine biosynthesis is increased during sepsis and if polyamines regulate mucosal protein synthesis. We examined the effect of sepsis in rats on polyamine biosynthesis in isolated jejunal Enterocytes and measured mucosal protein synthesis following inhibition of ornithine decarboxylase (ODC) activity with difluoromethylornithine. ODC and S-adenosylmethionine decarboxylase (SAMDC) activities and putrescine concentrations were increased in isolated jejunal Enterocytes 16 h after induction of sepsis by cecal ligation and puncture. Enterocyte spermidine and spermine levels were not influenced by sepsis. Mucosal ODC and SAMDC activities and polyamine levels were increased following treatment of rats with interleukin-1 but not tumor necrosis factor. Treatment of rats with difluoromethylornithine prevented the sepsis-induced increase in mucosal ODC activity, putrescine concentration, and protein synthesis rate. The results suggest that sepsis increases ODC and SAMDC activities and putrescine concentrations in Enterocytes of the small intestine. This metabolic response to sepsis may be regulated by interleukin-1 although other mechanisms may also be involved. Increased mucosal protein synthesis during sepsis may at least in part be regulated by increased putrescine levels.
J C Vallve - One of the best experts on this subject based on the ideXlab platform.
-
polyunsaturated fatty acids down regulate in vitro expression of the key intestinal cholesterol absorption protein npc1l1 no effect of monounsaturated nor saturated fatty acids
Journal of Nutritional Biochemistry, 2010Co-Authors: Adriana Alvaro, Roser Rosales, Lluís Masana, J C VallveAbstract:Abstract Several transporter proteins regulate intestinal cholesterol absorption. Of these proteins, NPC1L1 is a major contributor to this process. Fatty acids (FAs) modulate cholesterol absorption by a mechanism that remains unknown. We evaluate the effect of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) on the expression of NPC1L1 and others proteins associated with cholesterol absorption (SR-BI, ABCG5, ABCG8, ABCA1, CAV-1, ANX-2) in human Enterocytes in vitro. The role of SREBPs, PPARs, LXR and RXR in this process was also investigated. Caco-2/TC-7 Enterocytes were incubated for 24 h with a wide range of concentrations of FA–bovine serum albumin (50–300 μM). Gene expression was analyzed by quantitative real-time PCR. The NPC1L1 protein present in enterocyte membranes was analyzed using Western blot. NPC1L1 mRNA levels were reduced 35–58% by the n-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (P
-
polyunsaturated fatty acids down regulate in vitro expression of the key intestinal cholesterol absorption protein npc1l1 no effect of monounsaturated nor saturated fatty acids
Journal of Nutritional Biochemistry, 2010Co-Authors: Adriana Alvaro, Roser Rosales, Lluís Masana, J C VallveAbstract:Several transporter proteins regulate intestinal cholesterol absorption. Of these proteins, NPC1L1 is a major contributor to this process. Fatty acids (FAs) modulate cholesterol absorption by a mechanism that remains unknown. We evaluate the effect of saturated fatty acids (SFAs), monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) on the expression of NPC1L1 and others proteins associated with cholesterol absorption (SR-BI, ABCG5, ABCG8, ABCA1, CAV-1, ANX-2) in human Enterocytes in vitro. The role of SREBPs, PPARs, LXR and RXR in this process was also investigated. Caco-2/TC-7 Enterocytes were incubated for 24 h with a wide range of concentrations of FA–bovine serum albumin (50–300 μM). Gene expression was analyzed by quantitative real-time PCR. The NPC1L1 protein present in enterocyte membranes was analyzed using Western blot. NPC1L1 mRNA levels were reduced 35–58% by the n-3 PUFAs, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (P<.05). Linoleic acid (n-6), palmitic acid and oleic acid did not affect NPC1L1 mRNA expression. ABCA1 mRNA levels were reduced 44–70% by n-6 arachidonic acid and 43–55% by n-3 EPA (P<.05). LXR and LXR+RXR agonists decreased NPC1L1 mRNA expression by 28% and 57%, respectively (P<.05). A concentration of 200 μM of EPA and DHA decreased NPC1L1 protein expression in enterocyte membranes by 58% and 59%, respectively. We have demonstrated that the PUFAs n-3 EPA and DHA down-regulate NPC1L1 mRNA expression. In addition, PUFAs also down-regulate NPC1L1 protein expression in enterocyte membranes. LXR and RXR activation induced a similar repression effect. The lipid-lowering effect of n-3 PUFAs could be mediated in part by their action at the NPC1L1 gene level.
Eric S Hungness - One of the best experts on this subject based on the ideXlab platform.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Guang Jo Luo, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-kappaB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1beta-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1beta. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)alpha. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-κB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1β-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1β. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)α. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications. © 2003 Wiley-Liss, Inc.
Bruce W Robb - One of the best experts on this subject based on the ideXlab platform.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Guang Jo Luo, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-kappaB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1beta-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1beta. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)alpha. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-κB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1β-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1β. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)α. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications. © 2003 Wiley-Liss, Inc.
Dan D Hershko - One of the best experts on this subject based on the ideXlab platform.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Guang Jo Luo, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-kappaB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1beta-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1beta. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)alpha. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications.
-
sodium arsenite downregulates transcriptional activity of ap 1 and cre binding proteins in il 1β treated caco 2 cells by increasing the expression of the transcriptional repressor cremα
Journal of Cellular Biochemistry, 2003Co-Authors: Dan D Hershko, Bruce W Robb, Eric S Hungness, Per-olof HasselgrenAbstract:In recent studies, sodium arsenite (SA) inhibited IL-6 production in cultured intestinal epithelial cells, at least in part by downregulating the activity of nuclear factor-kappaB (NF-κB). The influence of SA on the activity of other transcription factors regulating the interleukin-6 (IL-6) gene in Enterocytes is not known. We tested the effect of SA on the activity of CCAAT/enhancer binding protein (C/EBP), activating protein-1 (AP-1), and CRE binding proteins in IL-1β-treated Caco-2 cells. DNA binding activity was determined by electrophoretic mobility shift assay (EMSA) and transcriptional activity by transfecting cells with luciferase reporter plasmids containing promoter constructs with binding sites for the individual transcription factors. DNA binding activity for all three transcription factors was increased after treatment with SA or IL-1β. In contrast, SA inhibited transcriptional activity of AP-1 and CRE binding proteins but not C/EBP. Additional experiments provided evidence that the inhibition of AP-1 and CRE mediated transcriptional activity was associated with, and probably caused by, increased expression of the transcriptional repressor cyclic AMP response element modulator (CREM)α. The present results are consistent with the concept that SA inhibits IL-6 production in stimulated Enterocytes by downregulating the transcriptional activity of several, but not all, IL-6-related transcription factors. Because of the multiple important biological functions of IL-6 in the enterocyte and gut mucosa, methods to regulate enterocyte IL-6 production have significant clinical implications. © 2003 Wiley-Liss, Inc.