Search results for "Primary culture"
showing 6 items of 6 documents
Streptomyces coelicolor secretoma protects astrocytes from oxidative stress
2016
Streptomycetes are gram-positive bacteria that produce about 2/3 of pharmaceutically active secondary metabolites, such as antibiotics, and anti-tumor, immunosuppressive, antifungal and antiparasitic agents. In this study, we investigated the possible effects of Streptomyces coelicolor extracts and putative vesicular fraction on primary cultures of rat astrocytes, in both physiological and stressed conditions, induced by treatment with hydrogen peroxide. Briefly, crude extracts and putative vesicular fractions were prepared from two S.coelicolor strains (M145 wild-type strain and bold F166 strain), and used to treat primary astrocytes, which were then also treated with hydrogen peroxide. Da…
In vitro evidences of epithelial to mesenchymal transition in low cell-density cultured human fetal hepatocytes
2017
Abstract Culturing fetal hepatocytes in high cell-density allowed stabilization of the hepatocyte phenotype up to 8 weeks, including the maintenance of liver-specific functions. On the other hand, when cultured at low cell-density, fetal hepatocytes underwent morphological modifications and acquired fibroblastic morphology. Since a switch from E-cadherin to vimentin expression accompanied these changes, we hypothesized the occurrence of epithelial-to-mesenchymal transition when fetal hepatocytes were cultured at low cell-density. Changes in gene expressionsuch as up-regulation of fibrosis-related geneswere also observed, suggesting that the low cell-density culture system promoted the acqui…
Endogenous nitric oxide is responsible for the early loss of P450 in cultured rat hepatocytes
1998
AbstractLoss of P450 during the early hours of monolayer formation is known to be the more serious limitation of primary cultured hepatocytes as an adequate model for the study of drug metabolism, toxicity and P450 induction. This study reports that endogenous nitric oxide (NO) formation is activated shortly after isolation by the classical collagenase-based liver perfusion methods. Both rapid P450 loss and aerobic mitochondrial energy metabolism impairment – with subsequent changes on glucose metabolism – are directly related to the high local generation of the radical at this stage. These effects can be reverted by the sole addition of NO biosynthesis inhibitors during liver perfusion and…
Kinetics of tienilic acid bioactivation and functional generation of drug–protein adducts in intact rat hepatocytes
2005
13 pages; Drug-induced autoimmune hepatitis is among the most severe hepatic idiosyncratic adverse drug reactions. Considered multifactorial, the disease combines immunological and metabolic aspects, the latter being to date much better known. As for many other model drugs, studies on tienilic acid (TA)-induced hepatitis have evidenced the existence of bioactivation during the hepatic oxidation of the drug, allowing the identification of the neoantigen of anti-LKM2 autoantibodies and the pathway responsible for its formation. However, most of these results are based on the use of microsomal fractions whose relevance to the liver in vivo still needs to be established. In the more complex int…
Effect of extracellular vesicles from CSF of multiple sclerosis patients and healthy controls on astrocytes in culture
2017
INTRODUCTION Secretion of extracellular vesicles (EVs) and EV-mediated exchange of molecules among brain cells, under physiological conditions, has been described years ago. At the same time, ability of EVs to transfer proteins and nucleic acids to the surrounding cells, thus modifying their phenotypes, has been clearly demonstrated for tumor cells of different origins, including brain cancers. More recently, involvement of EVs in pathological processes affecting the Central Nervous System (CNS), and their capacity of transferring damaging cargoes have been also suggested. To explore these functions, we exposed primary cultures of astrocytes to EVs isolated from cerebral spinal fluid (CSF) …
Microglia and α-synuclein implication in Parkinson's disease
2011
Age-related neurodegenerative disorders like Parkinson’s disease take an enormous toll on individuals and on society. Despite extensive efforts, Parkinson’s disease remains incurable and only very limited treatments exist. Indeed, Parkinson’s pathogenesis is still not clear and research on its molecular mechanisms is ongoing. In this study, we focused our interest on two abnormal events occurring in Parkinson’s patients, namely α-synuclein aggregation and microglial activation. We first investigated α-synuclein and its abnormal polymerisation. For this purpose, we developed novel methods, which allowed the in vitro production of different types of α-synuclein oligomers. Using highly sensiti…