Search results for "acidic"

Evidence for a common progenitor of epithelial and mesenchymal components of the liver

2013

Tissues of the adult organism maintain the homeostasis and respond to injury by means of progenitor/stem cell compartments capable to give rise to appropriate progeny. In organs composed by histotypes of different embryological origins (e.g. The liver), the tissue turnover may in theory involve different stem/precursor cells able to respond coordinately to physiological or pathological stimuli. In the liver, a progenitor cell compartment, giving rise to hepatocytes and cholangiocytes, can be activated by chronic injury inhibiting hepatocyte proliferation. The precursor compartment guaranteeing turnover of hepatic stellate cells (HSCs) (perisinusoidal cells implicated with the origin of the …

Primary cilia are required for cerebellar development and Shh-dependent expansion of progenitor pool

2008

Cerebellar granule cell precursors (GCPs), which give rise to the most abundant neuronal type in the mammalian brain, arise from a restricted pool of primary progenitors in the rhombic lip (RL). Sonic hedgehog (Shh) secreted by developing Purkinje cells is essential for the expansion of GCPs and for cerebellar morphogenesis. Recent studies have shown that the primary cilium concentrates components of Shh signaling and that this structure is required for Shh signaling. GCPs have a primary cilium on their surface [Del Cerro, M.P., Snider, R.S. (1972). Studies on the developing cerebellum. II. The ultrastructure of the external granular layer. J Comp Neurol 144, 131-64.]. Here, we show that 1)…

Cortical astrocytosis in juvenile rhesus monkeys infected with simian immunodeficiency virus

1993

The pattern of expression of GFAP immunoreactivity in astrocytes of the juvenile rhesus monkey cortex was examined following infection with simian immunodeficiency virus (SIV). Blocks of cerebral cortex plus subjacent white matter from saline- and formalin-perfused brain were examined by peroxidase-linked immunochemical and immunofluorescence staining of deparaffinized sections. Strong GFAP immunoreactivity was found in astrocytic cells in both uninfected and SIV-infected juvenile macaque in the subpial cerebral cortex and in subcortical white matter, where GFAP-positive cells were abundant. GFAP staining of cortical layers 2-6 on the other hand was weak or absent in three uninfected contro…

Dual effects of increased glycogen synthase kinase-3β activity on adult neurogenesis

2013

Adult neurogenesis, the generation of new neurons during the adulthood, is a process controlled by several kinases and phosphatases among which GSK3β exerts important functions. This protein is particularly abundant in the central nervous system, and its activity deregulation is believed to play a key role in chronic disorders such as Alzheimer's disease. Previously, we reported that in vivo overexpression of GSK3β (Tet/GSK3β mice) causes alterations in adult neurogenesis, leading to a depletion of the neurogenic niches. Here, we have further characterized those alterations, finding a delay in the switching-off of doublecortin marker as well as changes in the survival and death rates of imm…

Changes in Chemokines and Chemokine Receptors Expression in a Mouse Model of Alzheimer's Disease

2018

The amyloid precursor protein plus presenilin-1 (APP/PS1) mice are a frequently-used model for Alzheimer's disease studies (AD). However, the data relevant to which proteins are involved in inflammatory mechanism are not sufficiently well-studied using the AD mouse model. Using behavioral studies, quantitative RT-PCR and Western-blot techniques, significant findings were determined by the expression of proteins involved in inflammation comparing APP/PS1 and Wild type mice. Increased GFAP expression could be associated with the elevation in number of reactive astrocytes. IL-3 is involved in inflammation and ABDF1 intervenes normally in the transport across cell membranes and both were found …

SOLUBLE AND WATER-SWELLABLE POLYAMINOACIDIC CONSTRUCTS FOR DRUG DELIVERY

2004

Expression of the transcription factor Pax6 in the adult rat dentate gyrus

2005

The transcription factor Pax 6 is expressed in precursor cells during embryonic CNS development, and it plays an important role in the regulation of cell proliferation and neuronal fate determination. Pax 6-expressing cells are also present in the adult hippocampal dentate gyrus and subventricular zone/rostral migratory stream, regions in which neuronal precursors exist during adult life. In the adult dentate gyrus, precursor cells are located in the innermost portion of the granule cell layer, and Pax 6-expressing nuclei are most abundant in this region. To examine the putative role of Pax 6 in adult hippocampal neurogenesis, we have studied the proliferative activity, distribution, and ph…

Peroxisome proliferator-activated receptor γ ligands regulate neural stem cell proliferation and differentiation in vitro and in vivo.

2011

Peroxisome proliferator-activated receptor gamma (PPARγ) belongs to a family of ligand-activated nuclear receptors and its ligands are known to control many physiological and pathological situations. Its role in the central nervous system has been under intense analysis during the last years. Here we show a novel function for PPARγ in controlling stem cell expansion in the adult mammalian brain. Adult rats treated with pioglitazone, a specific ligand of PPARγ, had elevated numbers of proliferating progenitor cells in the subventricular zone and the rostral migratory stream. Electron microscopy analysis also showed important changes in the subventricular zone ultrastructure of pioglitazone-t…

Sea urchin embryos as a model system for studying autophagy induced by cadmium stress

2011

It is well known that sea urchin embryos are able to activate different defense strategies against stress. We previously demonstrated that cadmium treatment triggers the accumulation of metal in embryonic cells and the activation of defense systems depending on concentration and exposure time, through the synthesis of heat shock proteins and/or the initiation of apoptosis. Here we show that Paracentrotus lividus embryos exposed to Cd adopt autophagy as an additional stratagem to safeguard the developmental program. At present, there are no data focusing on the role of this process in embryo development of marine organisms. In this paper we utilized different techniques to detect autophagy i…

NG2 and GFAP co-expression after differentiation in cells transfected with mutant GFAP and in undifferentiated glioma cells

2020

Introduction: Alexander disease is a rare disorder caused by mutations in the gene coding for glial fibrillary acidic protein (GFAP). In a previous study, differentiation of neurospheres transfected with these mutations resulted in a cell type that expresses both GFAP and NG2. Objective: To determine the effect of molecular marker mutations in comparison to undifferentiated glioma cells simultaneously expressing GFAP and NG2. Methods: We used samples of human glioblastoma (GBM) and rat neurospheres transfected with GFAP mutations to analyse GFAP and NG2 expression after differentiation. We also performed an immunocytochemical analysis of neuronal differentiation for both cell types and dete…