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- Saksida, Tamara, et al.
(författare)
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Galectin-3 deficiency protects pancreatic islet cells from cytokine-triggered apoptosis in vitro
- 2013
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Ingår i: Journal of Cellular Physiology. - : Wiley. - 1097-4652 .- 0021-9541. ; 228:7, s. 1568-1576
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Tidskriftsartikel (refereegranskat)abstract
- Beta cell apoptosis is a hallmark of diabetes. Since we have previously shown that galectin-3 deficient (LGALS3/) mice are relatively resistant to diabetes induction, the aim of this study was to examine whether beta cell apoptosis depends on the presence of galectin-3 and to delineate the underlying mechanism. Deficiency of galectin-3, either hereditary or induced through application of chemical inhibitors, -lactose or TD139, supported survival and function of islet beta cells compromised by TNF-+IFN-+IL-1 stimulus. Similarly, inhibition of galectin-3 by -lactose or TD139 reduced cytokine-triggered apoptosis of beta cells, leading to conclusion that endogenous galectin-3 propagates beta apoptosis in the presence of an inflammatory milieu. Exploring apoptosis-related molecules expression in primary islet cells before and after treatment with cytokines we found that galectin-3 ablation affected the expression of major components of mitochondrial apoptotic pathway, such as BAX, caspase-9, Apaf, SMAC, caspase-3, and AIF. In contrast, anti-apoptotic molecules Bcl-2 and Bcl-XL were up-regulated in LGALS3/ islet cells when compared to wild-type (WT) counterparts (C57BL/6), resulting in increased ratio of anti-apoptotic versus pro-apoptotic molecules. However, Fas-triggered apoptotic pathway as well as extracellular signal-regulated kinase 1/2 (ERK1/2) was not influenced by LGALS-3 deletion. All together, these results point to an important role of endogenous galectin-3 in beta cell apoptosis in the inflammatory milieu that occurs during diabetes pathogenesis and implicates impairment of mitochondrial apoptotic pathway as a key event in protection from beta cell apoptosis in the absence of galectin-3. J. Cell. Physiol. 228: 15681576, 2013. (c) 2012 Wiley Periodicals, Inc.
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2. |
- Volarevic, Vladislav, et al.
(författare)
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Gal-3 regulates the capacity of dendritic cells to promote NKT-cell-induced liver injury
- 2015
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Ingår i: European Journal of Immunology. - : Wiley. - 1521-4141 .- 0014-2980. ; 45:2, s. 531-543
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Tidskriftsartikel (refereegranskat)abstract
- Galectin-3 (Gal-3), an endogenous lectin, exhibits ro- and anti-inflammatory effects in various disease conditions. In order to explore the role of Gal-3 in KT-cell-dependent pathology, we induced hepatitis in C57BL/6WT and al-3-deficient mice by using specific ligand for KT cells: alpha-galactosylceramide, glycolipid Ag presented by CD1d. The injection of alpha-galactosylceramide significantly enhanced expression of Gal-3 in liver NKT and dendritic cells (DCs). Genetic deletion or selective inhibition of Gal-3 (induced by Gal-3-inhibitor TD139) abrogated the susceptibility to NKT-cell-dependent hepatitis. Blood levels of pro-inflammatory cytokines (TNF-alpha-, IFN-gamma, IL-12) and their production by liver DCs and NKT cells were also downregulated. Genetic deletion or selective inhibition of Gal-3 alleviated influx of inflammatory CD11c(+) CD11b(+) DCs in the liver and favored tolerogenic phenotype and IL-10 production of liver NKT and DCs. Deletion of Gal-3 attenuated the capacity of DCs to support liver damage in the passive transfer experiments and to produce pro-inflammatory cytokines in vitro. Gal-3-deficient DCs failed to optimally stimulate production of pro-inflammatory cytokines in NKT cells, in vitro and in vivo. In conclusion, Gal-3 regulates the capacity of DCs to support NKT-cell-mediated liver injury, playing an important pro-inflammatory role in acute liver injury.
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3. |
- Volarevic, Vladislav, et al.
(författare)
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Galectin-3 deficiency prevents concanavalin A-induced hepatitis in mice
- 2012
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Ingår i: Hepatology. - : Ovid Technologies (Wolters Kluwer Health). - 1527-3350 .- 0270-9139. ; 55:6, s. 1954-1964
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Tidskriftsartikel (refereegranskat)abstract
- We used concanavalin A (Con A)-induced liver injury to study the role of galectin-3 (Gal-3) in the induction of inflammatory pathology and hepatocellular damage. We tested susceptibility to Con Ainduced hepatitis in galectin-3-deficient (Gal-3-/-) mice and analyzed the effects of pretreatment with a selective inhibitor of Gal-3 (TD139) in wild-type (WT) C57BL/6 mice, as evaluated by a liver enzyme test, quantitative histology, mononuclear cell (MNC) infiltration, cytokine production, intracellular staining of immune cells, and percentage of apoptotic MNCs in the liver. Gal-3-/- mice were less sensitive to Con Ainduced hepatitis and had a significantly lower number of activated lymphoid and dendritic cells (DCs) in the liver. The level of tumor necrosis factor alpha (TNFa), interferon gamma (IFN?), and interleukin (IL)-17 and -4 in the sera and the number of TNFa-, IFN?-, and IL-17- and -4-producing cluster of differentiation (CD)4+ cells as well as IL-12-producing CD11c+ DCs were lower, whereas the number of IL-10-producing CD4+ T cells and F4/80+ macrophages were significantly higher in livers of Gal-3-/- mice. Significantly higher percentages of late apoptotic Annexin V+ propidium-idodide+ liver-infiltrating MNCs and splenocytes were observed in Gal-3-/- mice, compared to WT mice. Pretreatment of WT C57BL/6 mice with TD139 led to the attenuation of liver injury and milder infiltration of IFN?- and IL-17- and -4-producing CD4+ T cells, as well as an increase in the total number of IL-10-producing CD4+ T cells and F4/80+ CD206+ alternatively activated macrophages and prevented the apoptosis of liver-infiltrating MNCs. Conclusions: Gal-3 plays an important proinflammatory role in Con Ainduced hepatitis by promoting the activation of T lymphocytes and natural killer T cells, maturation of DCs, secretion of proinflammatory cytokines, down-regulation of M2 macrophage polarization, and apoptosis of MNCs in the liver. (HEPATOLOGY 2012;55:19541964)
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