277 research outputs found
Advanced Oxidation Protein Products-Modified Albumin Induces Differentiation of RAW264.7 Macrophages into Dendritic-Like Cells Which Is Modulated by Cell Surface Thiols
Local accumulation of Advanced Oxidation Protein Products (AOPP) induces pro-inflammatory and pro-fibrotic processes in kidneys and is an independent predictor of renal fibrosis and of rapid decline of eGFR in patients with chronic kidney disease (CKD). In addition to kidney damage, circulating AOPP may be regarded as mediators of systemic oxidative stress and, in this capacity, they might play a role in the progression of atherosclerotic damage of arterial walls. Atherosclerosis is a chronic inflammatory disease that involves activation of innate and adaptive immunity. Dendritic cells (DCs) are key cells in this process, due to their role in antigen presentation, inflammation resolution and T cell activation. AOPP consist in oxidative modifications of proteins (such as albumin and fibrinogen) that mainly occur through myeloperoxidase (MPO)-derived hypochlorite (HOCl). HOCl modified proteins have been found in atherosclerotic lesions. The oxidizing environment and the shifts in cellular redox equilibrium trigger inflammation, activate immune cells and induce immune responses. Thus, surface thiol groups contribute to the regulation of immune functions. The aims of this work are: (1) to evaluate whether AOPP-proteins induce activation and differentiation of mature macrophages into dendritic cells in vitro; and (2) to define the role of cell surface thiol groups and of free radicals in this process. AOPP-proteins were prepared by in vitro incubation of human serum albumin (HSA) with HOCl. Mouse macrophage-like RAW264.7 were treated with various concentrations of AOPP-HSA with or without the antioxidant N-acetyl cysteine (NAC). Following 48 h of HSA-AOPP treatment, RAW264.7 morphological changes were evaluated by microscopic observation, while markers of dendritic lineage and activation (CD40, CD86, and MHC class II) and allogeneic T cell proliferation were evaluated by flow cytometry. Cell surface thiols were measured by AlexaFluor-maleimide binding, and ROS production was assessed as DCF fluorescence by flow cytometry. HSA-AOPP induced the differentiation of RAW264.7 cells into a dendritic-like phenotype, as shown by morphological changes, by increased CD40, CD86 and MHC class II surface expression and by induction of T cell proliferation. The cell surface thiols dose dependently decreased following HSA-AOPP treatment, while ROS production increased. NAC pre-treatment enhanced the amount of cell surface thiols and prevented their reduction due to treatment with AOPP. Both ROS production and RAW264.7 differentiation into DC-like cells induced by HSA-AOPP were reduced by NAC. Our results highlight that oxidized plasma proteins modulate specific immune responses of macrophages through a process involving changes in the thiol redox equilibrium. We suggest that this mechanism may play a role in determining the rapid progression of the atherosclerotic process observed in CKD patients
Silvano Arieti: remembering his message
This paper reviews the contributions of Silvano Arieti to the psychodynamic treatment of schizophrenia and places them in the context of the current era and its intellectual tensions regarding this disorder and its treatment. The author includes personal anecdotes to illustrate her thesis that psychodynamic approaches remain vitally important and are tragically underutilized currently . The International Society for the Psychological treatments of the Schizophrenias and other psychoses, ISPS, aims at redressing this proble
Caveolin-1 down-regulation inhibits insulin-like growth factor-I receptor signal transduction in H9C2 rat cardiomyoblasts.
Caveolin (Cav)-1, the major caveolar protein, directly interacts with IGF-I receptor (IGF-IR) and its intracellular substrates. To determine the role of Cav-1 in IGF-IR signaling, we transfected H9C2 cells with small interfering RNA specific for Cav-1-siRNA. The selective down-regulation of Cav-1 (90%) was associated with a smaller reduction of Cav-2, whereas Cav-3 expression was unaffected. A significant reduction of IGF-IR tyrosine phosphorylation in Cav-1-siRNA H9C2 cells was found compared with H9C2 control cells (Ctr-siRNA). The reduced IGF-IR autophosphorylation resulted in a decrease of insulin receptor substrate-1, Shc, and Akt activation. In addition, in Cav-1-siRNA H9C2 cells, IGF-I did not prevent apoptosis, suggesting that Cav-1 is required to mediate the antiapoptotic effect of IGF-I in cardiomyoblasts. The down-regulation of Cav-1 decreased IGF-IR activation and affected the ability of IGF-I to prevent apoptosis after serum withdrawal also in human umbilical vein endothelial cells. These results demonstrate that: 1) Cav-1 down-regulation negatively affects IGF-IR tyrosine phosphorylation; 2) this effect causes a reduced activation of insulin receptor substrate-1, Shc, and Akt; and 3) Cav-1 is involved in IGF-IR antiapoptotic signaling after serum deprivation
Time-course of acute myocardial infarction-dependent peripheral mobilisation of endothelial progenitor cells
La doxorubicina induce l’espressione di LOX-1R in cellule muscolari cardiache attraverso un incremento dello stress ossidativo: ruolo di molecole cardioprotettive
Protective effects of carvedilol against doxorubicin-induced apoptosis in cardiac muscle cells
Doxorubicin induces LOX-1 expression in cardiac myocytes via oxidative stress: role of cardioprotective agents
Carvedilol Prevents Doxorubicin-induced Free Radical release and Oxidative Damage in Cardiomyocytes.
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