Search results for " APOPTOSIS"
showing 10 items of 372 documents
Mechanisms involved in lipid accumulation and apoptosis induced by 1-nitropyrene in Hepa1c1c7 cells
2011
International audience; 1-Nitropyrene (1-NP) is a nitro-polycyclic aromatic hydrocarbon (nitro-PAH) present in diesel exhaust and bound to particular matter in urban air. We show that 1-NP and the referent PAH benzo(a)pyrene (BP) induce apoptosis and a lipid accumulation dependent on cytochrome P450 1A1-metabolites in mouse hepatoma cells, whereas 1-amino-pyrene had no effect. The caspase inhibitor, N-benzyloxycarbonyl-Val-Ala-Asp(O-Me) fluoromethyl ketone (Z-VAD-fmk), inhibits 1-NP-induced apoptosis, but failed to alter 1-NP-triggered lipid accumulation determined by Nile red staining. We further show that cholesterol and fatty acid contents are modified after nitro-PAH exposure and that 1…
Induction of Apoptosis and Chemosensitization by the Histone Deacetylase Inhibitor Trichostatin in Hepatocellular Carcinoma Cells: Molecular Analysis…
2011
The mRNA and protein levels of RKIP are reduced and those of YY1 increased in clinical HCC. Loss, mutation, or promoter hypermethylation of the RKIP gene may not account for the downregulation of RKIP in HCC. Histone deacetylation can silence gene expression and play a significant role in hepatocarcinogenesis. The histone deacetylase inhibitor (HDACI) trichostatin induced cell growth inhibition and proapoptotic effects in HA22T/VGH and HepG2 HCC cells; it also exhibited synergy with doxorubicin. Treatment with trichostatin caused histone hyperacetylation and down- or upregulated expression of different genes (such as β-catenin, cyclin D1, hTERT, XIAP, and IL-6). These changes might, at leas…
Induction of apoptosis by the proteasome inhibitor MG132 in human HCC cells: Possible correlation with specific caspase-dependent cleavage of β-caten…
2004
Proteasome inhibitors, like MG132, can exert cell growth inhibitory and apoptotic effects in different tumor types. The apoptotic mechanism of these compounds involves the activation of the effector caspases. beta-catenin, also an oncogene, represents one of the substrates of these proteases, but the consequences of its cleavage are poorly understood. We investigated its function during apoptosis induced by MG132 in three hepatocellular carcinoma (HCC) cell lines, endowed (HepG2 and HuH-6) or not (HA22T/VGH) with activating mutations of beta-catenin. Induction of apoptosis was associated with cell growth inhibition, accumulation of the cells at the G(2)/M phases of the cell cycle, as well a…
Cytoprotective Effect of Idebenone through Modulation of the Intrinsic Mitochondrial Pathway of Apoptosis in Human Retinal Pigment Epithelial Cells E…
2022
Idebenone is a ubiquinone short-chain synthetic analog with antioxidant properties, which is believed to restore mitochondrial ATP synthesis. As such, idebenone is investigated in numerous clinical trials for diseases of mitochondrial aetiology and it is authorized as a drug for the treatment of Leber’s hereditary optic neuropathy. Mitochondria of retinal pigment epithelium (RPE) are particularly vulnerable to oxidative damage associated with cellular senescence. Therefore, the aim of this study was to explore idebenone’s cytoprotective effect and its underlying mechanism. We used a human-RPE cell line (ARPE-19) exposed to idebenone pre-treatment for 24 h followed by conditions …
Acetic Acid Mediated for One-Pot Synthesis of Novel Pyrazolyl s-Triazine Derivatives for the Targeted Therapy of Triple-Negative Breast Tumor Cells (…
2022
Here, we described the synthesis of novel pyrazole-s-triazine derivatives via an easy one-pot procedure for the reaction of β-dicarbonyl compounds (ethylacetoacetate, 5,5-dimethyl-1,3-cyclohexadione or 1,3-cyclohexadionone) with N,N-dimethylformamide dimethylacetal, followed by addition of 2-hydrazinyl-4,6-disubstituted-s-triazine either in ethanol-acetic acid or neat acetic acid to afford a novel pyrazole and pyrazole-fused cycloalkanone systems. The synthetic protocol proved to be efficient, with a shorter reaction time and high chemical yield with broad substrates. The new pyrazolyl-s-triazine derivatives were tested against the following cell lines: MCF-7 (breast cancer); MDA-MB-231 (tr…
Effects of extra virgin olive oil phenols on HL60 cell lines sensitive and resistant to anthracyclines
2009
The aim of our study was to evaluate the capability of a crude extract of phenols from extra virgin olive oil of Moraiolo cultivar to induce apoptosis and/or differentiation in sensitive and resistant HL60 cell lines to anticancer drugs (Typical Multidrug Resistance). Our data highlight that the crude extract is able to induce apoptosis on both sensitive and resistant cells, whereas the exposure to a number of anticancer drugs does not induce apoptosis in resistant cells. In differentiation experiments we investigated the capability of crude extract of phenols to induce the expression of CD11 granulocytic or CD14 monocytic cell surface antigen in sensitive and resistant HL60 cell lines. At …
Hyaluronic Acid Present in the Tumor Microenvironment Can Negate the Pro-apototic Effect of a Recombinant Fragment of Human Surfactant Protein D on B…
2020
Copyright © 2020 Murugaiah, Agostinis, Varghese, Belmonte, Vieni, Alaql, Alrokayan, Khan, Kaur, Roberts, Madan, Bulla and Kishore. Human surfactant protein D (SP-D) belongs to the family of collectins that is composed of a characteristic amino-terminal collagenous region and a carboxy-terminal C-type lectin domain. Being present at the mucosal surfaces, SP-D acts as is a potent innate immune molecule and offers protection against non-self and altered self-such as pathogens, allergens, and tumour. Here, we examined the effect of a recombinant fragment of human SP-D (rfhSP-D) on a range of breast cancer lines. Breast cancer has four molecular subtypes characterised by varied expression of oes…
Age and immunity
2006
Abstract Longitudinal studies are defining progressive alterations to the immune system associated with increased mortality in the very elderly. Many of these changes are exacerbated by or even caused by chronic T cell stimulation by persistent antigen, particularly from Cytomegalovirus. The composition of T cell subsets, their functional integrity and representation in the repertoire are all markedly influenced by age and by CMV. How these findings relate to epidemiological, functional, genetic, genomic and proteomic studies of human T cell immunosenescence was the subject of intense debate at an international conference held just before Christmas 2005 in the Black Forest.
Role of persistent CMV infection in configuring T cell immunity in the elderly
2007
Abstract Ageing is associated with declines in many physiological parameters, including multiple immune system functions. The rate of acceleration of the frequency of death due to cardiovascular disease or cancer seems to increase with age from middle age up to around 80 years, plateauing thereafter. Mortality due to infectious disease, however, does not plateau, but continues to accelerate indefinitely. The elderly commonly possess oligoclonal expansions of T cells, especially of CD8 cells, which, surprisingly, are often associated with cytomegalovirus (CMV) seropositivity. This in turn is associated with many of the same phenotypic and functional alterations to T cell immunity that have b…
Increased autophagy and apoptosis contribute to muscle atrophy in a myotonic dystrophy type 1 Drosophila model
2015
ABSTRACT Muscle mass wasting is one of the most debilitating symptoms of myotonic dystrophy type 1 (DM1) disease, ultimately leading to immobility, respiratory defects, dysarthria, dysphagia and death in advanced stages of the disease. In order to study the molecular mechanisms leading to the degenerative loss of adult muscle tissue in DM1, we generated an inducible Drosophila model of expanded CTG trinucleotide repeat toxicity that resembles an adult-onset form of the disease. Heat-shock induced expression of 480 CUG repeats in adult flies resulted in a reduction in the area of the indirect flight muscles. In these model flies, reduction of muscle area was concomitant with increased apopto…