scholarly journals Bladder Cancer Chemosensitivity Is Affected by Paraoxonase-2 Expression

Antioxidants ◽  
2020 ◽  
Vol 9 (2) ◽  
pp. 175 ◽  
Author(s):  
Stefania Fumarola ◽  
Monia Cecati ◽  
Davide Sartini ◽  
Gianna Ferretti ◽  
Giulio Milanese ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Bladder Cancer ◽  
Caspase 3 ◽  
Reactive Oxygen ◽  
Caspase 8 ◽  
Activity Levels ◽  
Oxygen Species ◽  
T24 Cells ◽  
Before And After ◽  
And Migration

The goal of the current study was to identify potential roles of paraoxonase-2 in bladder carcinogenesis. T24 bladder cancer cells were transfected with plasmids inducing paraoxonase-2 silencing or overexpression. Upon the selection of clones stably down- or upregulating paraoxonase-2, cell proliferation, migration, and the production of reactive oxygen species were evaluated, before and after treatment with cisplatin and gemcitabine, used alone or in combination. The activity levels of both caspase-3 and caspase-8 were also analyzed. shRNA-mediated gene silencing and the overexpression of paraoxonase-2 revealed that the enzyme was able to promote both the proliferation and migration of T24 cells. Moreover, the knockdown of paraoxonase-2 was significantly associated with a reduced cell viability of T24 cells treated with chemotherapeutic drugs and led to both an increase of reactive oxygen species production and caspase-3 and caspase-8 activation. Conversely, under treatment with anti-neoplastic compounds, a higher proliferative capacity was found in T24 cells overexpressing paraoxonase-2 compared with controls. In addition, upon enzyme upregulation, both the production of reactive oxygen species and activation of caspase-3 and caspase-8 were reduced. Although further analyses will be required to fully understand the involvement of paraoxonase-2 in bladder tumorigenesis and in mechanisms leading to the development of chemoresistance, the data reported in this study seem to demonstrate that the enzyme could exert a great impact on tumor progression and susceptibility to chemotherapy, thus suggesting paraoxonase-2 as a novel and interesting molecular target for effective bladder cancer treatment.

scholarly journals Compound K Induces Apoptosis of Bladder Cancer T24 Cells Via Reactive Oxygen Species-Mediated p38 MAPK Pathway

2013 ◽  
Vol 28 (8) ◽  
pp. 607-614 ◽  
Author(s):  
Han Wang ◽  
Dandan Jiang ◽  
Jing Liu ◽  
Shuhong Ye ◽  
Shan Xiao ◽  
...  
Keyword(s):  
Reactive Oxygen Species ◽  
Bladder Cancer ◽  
P38 Mapk ◽  
Mapk Pathway ◽  
Reactive Oxygen ◽  
Oxygen Species ◽  
Compound K ◽  
T24 Cells ◽  
P38 Mapk Pathway

Protective Effects of Crataegus pinnatifida Extracts and Crataegolic Acid Against Neurotoxicity of Paraquat in PC12 Cells

2021 ◽  
Vol 20 (1) ◽  
pp. 76-83
Author(s):  
Chi-Sen Chang ◽  
Yuh-Chiang Shen ◽  
Chi-Wen Juan ◽  
Chia-Lin Chang ◽  
Po-Kai Lin
Keyword(s):  
Reactive Oxygen Species ◽  
Pc12 Cells ◽  
Cell Apoptosis ◽  
Active Component ◽  
Caspase 3 ◽  
Reactive Oxygen ◽  
B Cell Lymphoma ◽  
Oxygen Species ◽  
Protein Levels ◽  
Crataegus Pinnatifida

The neuroprotective mechanisms of Crataegus pinnatifida extracts and crataegolic acid were studied using paraquat induced cytotoxicity in PC12 cells. C. pinnatifida extracts were prepared using hexane, ethyl acetate, and 95% ethanol. Additionally, crataegolic acid (also known as maslinic acid) was found in C. pinnatifida extracts. Assessment methods included the examinations of cytotoxicity, intracellular reactive oxygen species and calcium changes, activity of caspase-3 and α-synuclein, apoptotic cell death, and the expression levels of the B-cell lymphoma 2 (Bcl-2) and BCL2-associated X (Bax) proteins to investigate the neuroprotective mechanisms of C. pinnatifida extracts and its active component, crataegolic acid. The three extracts and crataegolic acid exhibited potent neuroprotective actions against paraquat induced PC12 cell apoptosis at 5–20µg/mL and 80–100µM concentrations, respectively. The key protective mechanisms included decreasing cell apoptosis, upregulating Bcl-2 protein levels, and downregulating Bax protein levels. The 95% ethanol extract also decreased paraquat induced reactive oxygen species production, calcium overloading, and caspase-3 and α-synuclein activities. The beneficial effects of these extracts could be explained by the active component, crataegolic acid that also inhibited paraquat-induced apoptosis through the suppression of reactive oxygen species generation and the caspase-3 signaling pathway.

Abstract 097: Recombinant Human Erythropoietin Prevents Reactive Oxygen Species - Induced Apoptosis Via Akt and p38 MAPK Pathway During Hypoxia/ Reperfusion Injury

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Asiya Parvin Allaudeen ◽  
Ajay Devendran ◽  
John E Baker ◽  
Anuradha Dhanasekaran
Keyword(s):  
Reactive Oxygen Species ◽  
P38 Mapk ◽  
Caspase 3 ◽  
Mapk Pathway ◽  
Intact Cell ◽  
Reactive Oxygen ◽  
Protective Role ◽  
Oxygen Species ◽  
Human Erythropoietin ◽  
In Cells

Erythropoietin (EPO) is a cytokine produced primarily in the kidney that is essential for red blood cell production. Apart from playing a role in hematopoiesis, EPO also has a protective role in heart myocytes, ovarian, glial cells brain and retinal diseases. In this study we observed that recombinant human EPO (rhEPO) reduces Hypoxia/ Reperfusion (H/R) injury by virtue of its effect on EPO receptor prosurvival signaling pathway, which ultimately leads to reduced expression of apoptotic proteins and increased survival of cardiomyocytes. H9C2 cells were exposed to H/R with or without pretreatment using 10, 15 and 20 U/ml of rhEPO. We determined viability using MTT, nuclear fragmentation by Hoechst staining, apoptotic nuclei by Acridine orange and Ethidium bromide, Reactive Oxygen Species (ROS) by Dicholorofluoresin Diacetate and activity of late apoptotic protease, Caspase-3 by colorimetric Caspase-3 assay. The expression of mitochondrial superoxide dismutase (MnSOD) by RT-PCR and Western blot, phospho-Akt and p38 MAPK by Confocal microscopy were analyzed. Cell viability is increased in cells pretreated with rhEPO compared to cell exposed to H/R. Cells subjected to H/R showed early apoptotic and late apoptotic cells but showed normal nuclei with intact cell membrane in cells pretreated with rhEPO. Intracellular production of ROS and Caspase-3 activity was decreased in cells pretreated with rhEPO compared to cells exposed to H/R. The expression of MnSOD RNA and protein was up-regulated in response to rhEPO, but not in H/R. The phosphorylative activation of Akt, p38MAPK progressively diminished during H/R but increased in rhEPO pretreated cells. We show that rhEPO prevents apoptosis in cardiomyocytes, subjected to H/R injury via phosphorylation of Akt and p38MAPK. These results it is hoped would help us distinguish the cell signaling pathways involved in cardioprotection and thus would open new avenues in cardiovascular therapy.

Reactive oxygen species and caspase activation mediate silica-induced apoptosis in alveolar macrophages

2001 ◽  
Vol 280 (1) ◽  
pp. L10-L17 ◽  
Author(s):  
Han-Ming Shen ◽  
Zhuo Zhang ◽  
Qi-Feng Zhang ◽  
Choon-Nam Ong
Keyword(s):  
Reactive Oxygen Species ◽  
Cell Death ◽  
Alveolar Macrophages ◽  
Caspase 3 ◽  
Reactive Oxygen ◽  
Parp Cleavage ◽  
Oxygen Species ◽  
Caspase Activation ◽  
Caspase 9 ◽  
Induced Apoptosis

Alveolar macrophages (AMs) are the principal target cells of silica and occupy a key position in the pathogenesis of silica-related diseases. Silica has been found to induce apoptosis in AMs, whereas its underlying mechanisms involving the initiation and execution of apoptosis are largely unknown. The main objective of the present study was to examine the form of cell death caused by silica and the mechanisms involved. Silica-induced apoptosis in AMs was evaluated by terminal deoxynucleotidyltransferase-mediated dUTP nick end-labeling assay and cell cycle/DNA content analysis. The elevated level of reactive oxygen species (ROS), caspase-9 and caspase-3 activation, and poly(ADP-ribose) polymerase (PARP) cleavage in silica-treated AMs were also determined. The results showed that there was a temporal pattern of apoptotic events in silica-treated AMs, starting with ROS formation and followed by caspase-9 and caspase-3 activation, PARP cleavage, and DNA fragmentation. Silica-induced apoptosis was significantly attenuated by a caspase-3 inhibitor, N-acetyl-Asp-Glu-Val-Asp aldehyde, and ebselen, a potent antioxidant. These findings suggest that apoptosis is an important form of cell death caused by silica exposure in which the elevated ROS level that results from silica exposure may act as an initiator, leading to caspase activation and PARP cleavage to execute the apoptotic process.

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