Search results for "death"
showing 10 items of 1744 documents
Beauvericin-induced cytotoxicity via ROS production and mitochondrial damage in Caco-2 cells.
2013
The cytotoxicity of beauvericin (BEA) on human colon adenocarcinoma (Caco-2) cells was studied as a function of time. Moreover, the oxidative damage and cell death endpoints were monitored after 24, 48 and 72 h. After BEA exposure, the IC₅₀ values ranged from 1.9 ± 0.7 to 20.6 ± 6.9 μM. A decrease in reduced glutathione (GSH; 31%) levels, as well as an increase in oxidized glutathione (GSSG, 20%) was observed. In the presence of BEA, reactive oxygen species (ROS) level was highly increased at an early stage with the highest production of 2.0-fold higher than the control that was observed at 120 min. BEA induced cell death by mitochondria-dependent apoptotic process with loss of the mitochon…
TTAS a New Stilbene Derivative that Induces Apoptosis in Leishmania Infantum
2012
Leishmania parasites are able to undergo apoptosis (programmed cell death), similarly to mammalian cells. Recently it was demonstrated in vitro the anti-leishmanial effect of some natural and synthetic stilbenoids including resveratrol and piceatannol. In this study we evaluated the Leishmanicidal activity of a pool of stilbene derivatives which had previously shown high apoptotic efficacy against neoplastic cells. All the compounds tested were capable to decrease the parasite viability in a dose-dependent manner. Trans-stilbenes proved to be markedly more effective than cis-isomers. This was different from that observed in tumor cells in which cis-stilbenes were more potent cytotoxic agent…
Staurosporine-induced apoptosis in Chang liver cells is associated with down-regulation of Bcl-2 and Bcl-XL.
2004
A potent inhibitor of serine/threonine kinases, staurosporine exerts antiproliferative and apoptotic effects in many cancer cells, although the exact mechanism of its action is still unclear. This study examines the effects of staurosporine on Chang liver cells, an immortalized non-tumor cell line, in comparison with those caused in HuH-6 and HepG2 cells, two human hepatoma cell lines. Our results provide evidence that staurosporine promotes apoptosis in Chang liver cells as observed by flow cytometric analysis and acridine orange/ethidium bromide staining. The effect appeared already after 8 h of treatment and increased with treatment time and dose. After 48 h of exposure to 200 nM stauros…
Synthesis and antiproliferative activity of thiazolyl-bis-pyrrolo[2,3-b]pyridines and indolyl-thiazolyl-pyrrolo[2,3-c]pyridines, nortopsentin analogu…
2015
Two new series of nortopsentin analogues, in which the imidazole ring of the natural product was replaced by thiazole and indole units were both substituted by 7-azaindole moieties or one indole unit was replaced by a 6-azaindole portion, were efficiently synthesized. Compounds belonging to both series inhibited the growth of HCT-116 colorectal cancer cells at low micromolar concentrations, whereas they did not affect the viability of normal-like intestinal cells. A compound of the former series induced apoptosis, evident as externalization of plasma membrane phosphatidylserine (PS), and changes of mitochondrial trans-membrane potential, while blocking the cell cycle in G2/M phase. In contr…
Glutathione peroxidase-1 in health and disease: from molecular mechanisms to therapeutic opportunities.
2011
Reactive oxygen species, such as superoxide and hydrogen peroxide, are generated in all cells by mitochondrial and enzymatic sources. Left unchecked, these reactive species can cause oxidative damage to DNA, proteins, and membrane lipids. Glutathione peroxidase-1 (GPx-1) is an intracellular antioxidant enzyme that enzymatically reduces hydrogen peroxide to water to limit its harmful effects. Certain reactive oxygen species, such as hydrogen peroxide, are also essential for growth factor-mediated signal transduction, mitochondrial function, and maintenance of normal thiol redox-balance. Thus, by limiting hydrogen peroxide accumulation, GPx-1 also modulates these processes. This review explor…
Galectin-3 Impairment of MYCN-Dependent Apoptosis-Sensitive Phenotype Is Antagonized by Nutlin-3 in Neuroblastoma Cells
2012
MYCN amplification occurs in about 20-25% of human neuroblastomas and characterizes the majority of the high-risk cases, which display less than 50% prolonged survival rate despite intense multimodal treatment. Somehow paradoxically, MYCN also sensitizes neuroblastoma cells to apoptosis, understanding the molecular mechanisms of which might be relevant for the therapy of MYCN amplified neuroblastoma. We recently reported that the apoptosis-sensitive phenotype induced by MYCN is linked to stabilization of p53 and its proapoptotic kinase HIPK2. In MYCN primed neuroblastoma cells, further activation of both HIPK2 and p53 by Nutlin-3 leads to massive apoptosis in vitro and to tumor shrinkage an…
ΔNp73β is oncogenic in hepatocellular carcinoma by blocking apoptosis signaling via death receptors and mitochondria
2010
p73 belongs to the p53 family of transcription factors known to regulate cell cycle and apoptosis. The Trp73 gene has two promoters that drive the expression of two major p73 isoform subfamilies: TA and ΔN. In general, TAp73 isoforms show proapoptotic activities, whereas members of the N-terminally truncated (ΔN) p73 subfamily that lack the transactivation domain show antiapoptotic functions. We found that upregulation of ΔNp73 in hepatocellular carcinoma (HCC) correlated with reduced survival. Here, we investigated the molecular mechanisms accounting for the oncogenic role of ΔNp73 in HCC.ΔNp73β can directly interfere with the transcriptional activation function of the TA (containing the t…
Logistic Growth Described by Birth-Death and Diffusion Processes
2019
We consider the logistic growth model and analyze its relevant properties, such as the limits, the monotony, the concavity, the inflection point, the maximum specific growth rate, the lag time, and the threshold crossing time problem. We also perform a comparison with other growth models, such as the Gompertz, Korf, and modified Korf models. Moreover, we focus on some stochastic counterparts of the logistic model. First, we study a time-inhomogeneous linear birth-death process whose conditional mean satisfies an equation of the same form of the logistic one. We also find a sufficient and necessary condition in order to have a logistic mean even in the presence of an absorbing endpoint. Then…
Applying Benford’s Law to Monitor Death Registration Data: A Management Tool for the COVID-19 Pandemic
2021
In Spain, the COVID-19 pandemic has impacted the various regions of the country differ7 ently. The availability of reliable and up-to-date information has proved to be fundamental for the 8 management of this health crisis. However, especially during the first wave of the pandemic (Feb9 ruary-August 2020), the disparity in the recording criteria and in the timing of providing these fig10 ures to the central government created controversy and confusion regarding the real dimension of 11 the pandemic. It is therefore necessary to have objective and homogeneous criteria at the national 12 level to guide health managers in the correct recording and evaluation of the magnitude of the pan13 demic…
Non-hermitian operator modelling of basic cancer cell dynamics
2018
We propose a dynamical system of tumor cells proliferation based on operatorial methods. The approach we propose is quantum-like: we use ladder and number operators to describe healthy and tumor cells birth and death, and the evolution is ruled by a non-hermitian Hamiltonian which includes, in a non reversible way, the basic biological mechanisms we consider for the system. We show that this approach is rather efficient in describing some processes of the cells. We further add some medical treatment, described by adding a suitable term in the Hamiltonian, which controls and limits the growth of tumor cells, and we propose an optimal approach to stop, and reverse, this growth.