Search results for "ISMU"
showing 10 items of 685 documents
Production of superoxide by human malignant melanoma cells.
1998
Metastasis is a complicated multi-step process involving interactions between tumour cells, the extracellular matrix and the vessel walls. Experimental observations suggest that leucocyte migration and function could be a suitable model in order to understand tumour cell dissemination. In the present report we show and quantify the production of free radicals by human malignant melanoma cells (St-ml12) by means of a spectrophotometrical method, using an enzyme immunoassay reader. Endothelial cells and activated polymorphonuclear leucocytes were used as controls. Melanoma cells without stimulants produced large amounts of superoxide anion at an increasing rate in relation to time, which coul…
The oxygen radicals involved in the toxicity induced by parthenolide in MDA-MB-231 cells
2014
It has been shown that the sesquiterpene lactone parthenolide lowers the viability of MDA-MB-231 breast cancer cells, in correlation with oxidative stress. The present report examined the different radical species produced during parthenolide treatment and their possible role in the toxicity caused by the drug. Time course experiments showed that in the first phase of treatment (0-8 h), and in particular in the first 3 h, parthenolide induced dichlorofluorescein (DCF) signal in a large percentage of cells, while dihydroethidium (DHE) signal was not stimulated. Since the effect on DCF signal was suppressed by apocynin and diphenyleneiodonium (DPI), two inhibitors of NADPH oxidase (NOX), we s…
WIN 55,212-2, agonist of cannabinoid receptors, prevents amyloid β1-42 effects on astrocytes in primary culture
2015
Alzheimer's disease (AD), a neurodegenerative illness involving synaptic dysfunction with extracellular accumulation of Aβ1-42 toxic peptide, glial activation, inflammatory response and oxidative stress, can lead to neuronal death. Endogenous cannabinoid system is implicated in physiological and physiopathological events in central nervous system (CNS), and changes in this system are related to many human diseases, including AD. However, studies on the effects of cannabinoids on astrocytes functions are scarce. In primary cultured astrocytes we studied cellular viability using MTT assay. Inflammatory and oxidative stress mediators were determined by ELISA and Western-blot techniques both in…
Capsaicin Intake and Oral Carcinogenesis: a Systematic Review
2021
Background Chili is the most heavily and frequently consumed spice, either as a flavouring or colouring agent, and it is also a major source of pro-vitamin A, vitamin E and C. The main capsinoidcapsaicinoid found in chili peppers is capsaicin. It has been demonstrated that capsaicin acts as a cancer-suppressing agent through its antioxidant and anti-inflammatory effects, by blocking several signal transduction pathways. Oral squamous cell carcinoma is one of the most prevalent cancer worldwide. It is noteworthy that in countries where populations of diverse ethnic groups co-exist, differences have been observed in terms of incidence of oral cancer. The variances in their diet could explain,…
Heterodimer formation of wild-type and amyotrophic lateral sclerosis-causing mutant Cu/Zn-superoxide dismutase induces toxicity independent of protei…
2008
Recent studies provide evidence that wild-type Cu/Zn-superoxide dismutase (SOD1(hWT)) might be an important factor in mutant SOD1-mediated amyotrophic lateral sclerosis (ALS). In order to investigate its functional role in the pathogenesis of ALS, we designed fusion proteins of two SOD1 monomers linked by a polypeptide. We demonstrated that wild-type-like mutants, but not SOD1(G85R) homodimers, as well as mutant heterodimers including SOD1(G85R)-SOD1(hWT) display dismutase activity. Mutant homodimers showed an increased aggregation compared with the corresponding heterodimers in cell cultures and transgenic Caenorhabditis elegans, although SOD1(G85R) heterodimers are more toxic in functiona…
Resveratrol reduces oxidative stress and cell death and increases mitochondrial antioxidants and XIAP in PC6.3-cells.
2010
Resveratrol, a polyphenol derived e.g. from red grapes, has been shown to mediate several positive biological actions such as protection of cells against oxidative stress. It can also influence cell signaling, but the mechanisms behind its antioxidant properties are largely unknown. Here we show that RSV reduces oxidative stress and enhances cell survival in PC6.3 cells depending on the concentration. In these cells, RSV increased the levels of antioxidants, SOD2 and TRX2, and of X chromosome-linked inhibitor of apoptosis protein. RSV also activated NFκB signaling as shown using luciferase reporter constructs. These findings show that RSV regulates oxidative stress and mitochondrial antioxi…
Multifaceted effects of oligodendroglial exosomes on neurons: impact on neuronal firing rate, signal transduction and gene regulation.
2014
Exosomes are small membranous vesicles of endocytic origin that are released by almost every cell type. They exert versatile functions in intercellular communication important for many physiological and pathological processes. Recently, exosomes attracted interest with regard to their role in cell–cell communication in the nervous system. We have shown that exosomes released from oligodendrocytes upon stimulation with the neurotransmitter glutamate are internalized by neurons and enhance the neuronal stress tolerance. Here, we demonstrate that oligodendroglial exosomes also promote neuronal survival during oxygen–glucose deprivation, a model of cerebral ischaemia. We show the transfer from…
Impact of Thermal Treatment on the Surface of Na0.5Bi0.5TiO3-Based Ceramics
2021
This research was funded by the European Regional Development Fund, grant number 1.1.1.2/VIAA/3/19/558. The Institute of Solid State Physics, University of Latvia as the Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme, grant number 739508.
In vitro and in vivo trypanosomicidal activity of pyrazole-containing macrocyclic and macrobicyclic polyamines: their action on acute and chronic pha…
2012
The in vitro and in vivo anti- Trypanosoma cruzi activity of the pyrazole-containing macrobicyclic polyamine 1 and N-methyl- and N-benzyl-substituted monocyclic polyamines 2 and 3 was studied. Activity against both the acute and chronic phases of Chagas disease was considered. The compounds were more active against the parasite and less toxic against Vero cells than the reference drug benznidazole, but 1 and 2 were especially effective, where cryptand 1 was the most active, particularly in the chronic phase. The activity results found for these compounds were complemented and discussed by considering their inhibitory effect on the iron superoxide dismutase enzyme of the parasite, the nature…
Scorpiand-like azamacrocycles prevent the chronic establishment of Trypanosoma cruzi in a murine model.
2013
Chagas disease is today one of the most important neglected diseases for its upcoming expansion to non-endemic areas and has become a threat to blood recipients in many countries. In this study, the trypanocidal activity of ten derivatives of a family of aza-scorpiand like macrocycles is evaluated against Trypanosoma cruzi in vitro and in vivo murine model in which the acute and chronic phases of Chagas disease were analyzed. The compounds 4, 3 and 1 were found to be more active against the parasite and less toxic against Vero cells than the reference drug benznidazole, 4 being the most active compound, particularly in the chronic phase. While all these compounds showed a remarkable degree …