Abstract 2808: Luteolin inhibits cell proliferation and induces cell apoptosis via down-regulation of mitochondrial membrane potential in esophageal carcinoma cells EC1 and KYSE450

Abstract Background Parkinson’s disease (PD) is the second most common neurodegenerative disease after Alzheimer's disease. The oxidative stress is an important component of the pathogenesis of PD. Artemisinin (ART) has antioxidant and neuroprotective effects. The purpose of this study is to explore the neuroprotective effect of ART on 1-methyl-4-phenyliodine iodide (MPP +)-treated SH-SY5Y cells and underlying mechanism. Methods We used MPP+-treated SH-SY5Y cells to study the neuroprotective effect of ART. Cell viability was measured by MTT assay after incubating the cells with MPP+ and/or ART for 24 h. DCFH-DA was used to detect the level of intracellular reactive oxygen species (ROS), and WST-8 was used to detect the level of superoxide dismutase (SOD). The level of intracellular reduced glutathione (GSH) was detected with 5,5΄-dithiobis-(2-nitrobenzoic acid), and the level of malondialdehyde (MDA) was assessed based on the reaction of MDA and thiobarbituric acid. A mitochondrial membrane potential detection kit (JC-1) was used to detect changes in the mitochondrial membrane potential (MMP), and an Annexin V-FITC cell apoptosis kit was used to detect cell apoptosis. The expression levels of caspase-3, cleaved caspase-3 and the autophagy-related proteins LC3, beclin-1, and p62 were detected by Western blotting. In addition, to verify the change in autophagy, we used immunofluorescence to detect the expression of LC3 and p62. Results No significant cytotoxicity was observed at ART concentrations up to 40 μM. ART could significantly increase the viability of SH-SY5Y cells treated with MPP+ and reduce oxidative stress damage and apoptosis. In addition, the Western blotting and immunofluorescence results showed that MPP+ treatment could increase the protein expression of beclin1 and LC3II/LC3I and decrease the protein expression of p62, indicating that MPP+ treatment could induce autophagy. Simultaneous treatment with ART and MPP+ could decrease the protein expression of beclin1 and LC3II/LC3I and increase the protein expression of p62, indicating that ART could decrease the level of autophagy induced by MPP+. Conclusion Our results indicate that ART has a protective effect on MPP+-treated SH-SY5Y cells by the antioxidant, antiapoptotic activities and inhibition of autophagy. Our findings may provide new hope for the prevention and treatment of PD.

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PLAUR Confers Resistance to Gefitinib Through EGFR/P-AKT/Survivin Signaling Pathway

Cellular Physiology and Biochemistry ◽

10.1159/000491071 ◽

2018 ◽

Vol 47 (5) ◽

pp. 1909-1924 ◽

Cited By ~ 8

Author(s):

Jian Zhou ◽

Kwang Joo Kwak ◽

Zuoren Wu ◽

Dawei Yang ◽

Jing Li ◽

...

Keyword(s):

Cell Proliferation ◽

Membrane Potential ◽

Tyrosine Kinase ◽

Lung Adenocarcinoma ◽

Signaling Pathway ◽

Cell Apoptosis ◽

Mitochondrial Membrane ◽

Human Lung ◽

Nsclc Patients ◽

Gefitinib Resistance

Background/Aims: Tyrosine kinase inhibitor gefitinib significantly improves the survival of patients with non-small-cell lung cancer (NSCLC) by inhibiting epidermal growth factor receptor (EGFR) tyrosine kinase. However, patients eventually develop resistance to gefitinib through uncharacterized mechanisms. It is known that plasminogen activator urokinase receptor (PLAUR) plays an important role in cell proliferation, migration and apoptosis. However, the role of PLAUR, particularly exosomal PLAUR in gefitinib resistance in NSCLC has not been reported. The aim of this study is to determine the relationship between PLAUR and gefitinib resistance. Methods: In this study, a tethered cationic lipoplex nanoparticle (TCLN) biochip containing molecular beacons was used as probes to detect PLAUR mRNA in plasma exosomes from patients with gefitinib-sensitive and -resistant NSCLC. In vitro, Real-time PCR was used to examine the expression of PLAUR mRNA and Western blot was applied to examine the expression of related proteins. The gene knockdown was achieved by Lentivirus based RNA silence technique. The cell counting kit-8 assay and EdU incorporation were used to examine cell proliferation. The flow cytometry was applied to determine cell apoptosis and cell cycle, while the mitochondrial membrane potential was measured by JC-1 dye assay. Signaling pathway affected by PLAUR knockdown was identified by cDNA Microarray. The effect of PLAUR knockdown on tumorigenesis was analyzed in vivo. Results: We found that the exosomal PLAUR mRNA in the plasma of gefitinib-resistant NSCLC patients was significantly increased compared to that of gefitinib-sensitive NSCLC patients. The PLAUR mRNA and soluble PLAUR protein were also significantly increased in gefitinib-resistant human lung adenocarcinoma PC9R cells compared to gefitinib-sensitive PC9 cells. Silencing PLAUR in PC9R cells impaired mitochondrial membrane potential and increased cell apoptosis via EGFR/p-AKT/survivin signaling pathway. Furthermore, EGFR was upregulated in the geftinib-resistant PC9R cells, and knockdown of EGFR significantly increased cell apoptosis. Conclusions: Taken together, our results demonstrated that PLAUR induces geftinib-resistance through EGFR/p-AKT/survivin signaling pathway in gefitinib-resistant human lung adenocarcinoma cells. PLAUR could be a novel therapeutic target for gefitinib-resistant NSCLC patients.

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K+/H+-antiporter nigericin arrests DNA synthesis in Ehrlich ascites carcinoma cells

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.86.17.6626 ◽

1989 ◽

Vol 86 (17) ◽

pp. 6626-6629 ◽

Cited By ~ 18

Author(s):

L B Margolis ◽

Y u Novikova I ◽

I A Rozovskaya ◽

V P Skulachev

Keyword(s):

Membrane Potential ◽

Dna Synthesis ◽

Mitochondrial Membrane Potential ◽

Mitochondrial Membrane ◽

Ehrlich Ascites Carcinoma ◽

Carcinoma Cells ◽

Low Concentrations ◽

Ehrlich Ascites ◽

Inhibition Of Dna Synthesis ◽

Dna Synthesis Inhibition

Acidification of the cytoplasm of Ehrlich ascites carcinoma cells to pH 6.3 arrests DNA synthesis in these cells. Such an effect can be achieved by incubating the cells at pH 6.2 or by adding low concentrations of the K+/H+ antiporter, the antibiotic nigericin, at neutral pH. Glucose and anaerobiosis potentiate the nigericin effect. The inhibition of DNA synthesis by nigericin occurs without any significant decrease in the ATP concentration and in the mitochondrial membrane potential. The DNA synthesis inhibition is caused neither by a decrease in the intracellular [K+] nor by an increase in the intracellular [Na+] accompanying the nigericin effect (at least at low concentrations of the antibiotic). Nigericin should thus be regarded as a type of a cytostatic primarily affecting intracellular pH.

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Effects of Berberine on Cell Cycle, DNA, Reactive Oxygen Species, and Apoptosis in L929 Murine Fibroblast Cells

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2015/796306 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 7

Author(s):

Manman Gu ◽

Jing Xu ◽

Chunyang Han ◽

Youxi Kang ◽

Tengfei Liu ◽

...

Keyword(s):

Reactive Oxygen Species ◽

Cell Cycle ◽

Dna Damage ◽

Membrane Potential ◽

Mitochondrial Membrane Potential ◽

Cell Apoptosis ◽

Mitochondrial Membrane ◽

Oxygen Species ◽

Cycle Arrest ◽

Murine Fibroblast

Berberine, an isoquinoline alkaloid isolated from several traditional Chinese herbal medicines (TCM), exhibits a strong antimicrobial activity in the treatment of diarrhea. However, it causes human as well as animal toxicity from heavy dosage. The present study was conducted to investigate the cytotoxicity of berberine and its possible trigger mechanisms resulting in cell cycle arrest, DNA damage, ROS (reactive oxygen species) level, mitochondrial membrane potential change, and cell apoptosis in L929 murine fibroblast (L929) cells. The cells were culturedin vitroand treated with different concentrations of berberine for 24 h. The results showed that cell viability was significantly decreased in a subjected dose-dependent state; berberine concentrations were higher than 0.05 mg/mL. Berberine at a concentration above 0.1 mg/mL altered the morphology of L929 cells. Cells at G2/M phase were clear that the level of ROS and cell apoptosis rates increased in 0.1 mg/mL group. Each DNA damage indicator score (DIS) increased in groups where concentration of berberine was above 0.025 mg/mL. The mitochondrial membrane potential counteractive balance mechanics were significantly altered when concentrations of berberine were above 0.005 mg/mL. In all, the present study suggested that berberine at high dosage exhibited cytotoxicity on L929 which was related to resultant: cell cycle arrest; DNA damage; accumulation of intracellular ROS; reduction of mitochondrial membrane potential; and cell apoptosis.

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Potential Crosstalk Of Ca2+-ROS Dependent Mechanism Involved In Kasumi cells’ Apoptosis Induced By Lentivirus-Mediated HO-1 siRNA

Blood ◽

10.1182/blood.v122.21.5558.5558 ◽

2013 ◽

Vol 122 (21) ◽

pp. 5558-5558

Author(s):

Jishi Wang ◽

Wei Sixi ◽

Wang Yating ◽

Chai Qixiang

Keyword(s):

Membrane Potential ◽

Cell Viability ◽

Mitochondrial Membrane Potential ◽

Cell Apoptosis ◽

Mitochondrial Membrane ◽

The Other ◽

Ros Generation ◽

Dependent Manner ◽

Realtime Pcr ◽

Protein Expressions

Abstract Aim Using lentivirus-mediated HO-1 siRNA (lenti-siHO-1-GFP) to silence the HO-1 gene in Kasumi cells so as to explore the role and mechanism of HO-1 on cell apoptosis. Methods To infect Kasumi cells with lenti-siHO-1-GFP and check the infection efficiency by using fluorescence microscopy and flow cytometry (FCM). Experimental group was divided into three groups: untreated Kasumi (K), infected Kasumi by empty vector (lenti-GFP-K) and infected Kasumi by lentivirus-mediated HO-1 siRNA (lenti-siHO-1-K). The HO-1 expression of each group was detected by realtime PCR. Fluo3-AM method was used to detect the intracellular Ca2+ accumulation. DCFH-DA was used for the measurement of intracellular ROS. The change of mitochondrial membrane potential was evaluated by JC-1 stainning by using FCM. After being treated with various concentrations of daunorubicin for 24, 48, and 72 h respectively, cell viability was determined by MTT assay. Cell apoptosis was determined by FCM following with cells dual-stained with Annexin-V-FITC and propidium iodide (PI). The mRNA of HO-1 and apoptosis-related genes were analyzed by realtime PCR and, the expressions of their corresponding protein were determined by western blot. Additionally, After treating with 10mM Ca2+chelator BAPTA-AM and 0.5mM NAC for 12h, Ca2+ accumulation, ROS generation, the expression of HO-1 and apoptosis-related genes were detected respectively. Result presented in mean±sd manner. Results After lenti-siHO-1-GFP infection for 48h, we could observe the fluorescence clear, the fluorescent intensity was 95.87% after 72 hours. The HO-1 silencing efficiency of lenti-siHO-1-K was 77.00%. MTT result showed that daunorubicin exerted moderate inhibitory effects on cell proliferation in a dose and time dependent manner. With the same treating conditions, the cell viability of lenti-siHO-1-K group was significantly lower than the other two groups(e.g 49.20±1.30% survival in lenti-siHO-1-K group, 72.40±1.90% in K group and 74.10±2.10% in lenti-GFP-K group after being treated by 5ug/ml DNR,respectively, p=0.014), while the apoptosis rate was higher than the other two groups(e.g 75.77±3.41% in lenti-siHO-1-K group, 23.72±2.03% in K group and 26.10±1.95% in lenti-GFP-K group after being treated by 5ug/ml DNR,respectively, p=0.011). Compared with other two groups, the lenti-siHO-1-K group showed a downregulation in the mRNA and protein expression of HO-1. The mRNA and protein expressions of cyto-C, caspase3, caspase8, caspase9 and caspase12 in lenti-siHO-1-K group were upregulated after exposure to 5ug/ml daunorubicin for 24 hours. Compared with K and lenti-GFP-K groups, Ca2+ accumulation in lenti-siHO-1-K group was increased significantly(e.g 40.35±2.10% in lenti-siHO-1-K group, 17.30±1.81% in K group and 14.15±1.75% in lenti-GFP-K group,respectively, p=0.041). The ROS generation was higher than the other two groups(e.g 47.65±2.05% in lenti-siHO-1-K group, 21.30±1.94% in K group and19.90±2.01% in lenti-GFP-K group,respectively, p=0.037). The ratio of Green/Red fluorescence intensity increased significantly in lenti-siHO-1-K group(e.g 0.704±0.06 in lenti-siHO-1-K group, 0.57±0.09 in K group and 0.527±0.05 in lenti-GFP-K group, respectively, p=0.042). After exposure to 10mM BAPTA-AM and 0.1mM NAC alone or combined with, both the intracellular Ca2+accumulation and the ROS level in lenti-siHO-1-K group reduced(17.59±1.01% of Ca2+acumulation and 19.78±1.3% of ROS production after BAPTA-AM treatment alone, 23.42±1.97% of Ca2+and 15.47±1.14% of ROS after being treated by NAC alone, 16.52±1.23% of Ca2+and 14.37±1.21% of ROS after treatment by both agent) , while the mRNA and protein expressions of cyto-C, caspase3, caspase8, caspase9 and caspase12, decreased significantly. Conclusion HO-1 gene silencing played a role in pro-apoptosis in Kasumi cells. The mechanism may be related to the endoplasmic reticulum stress and abnormal accumulation of intracellular Ca2+, ROS generation, descending of the mitochondrial membrane potential and release cyto-C, then further activated the caspases cascade and promoted apoptosis. However, it tended to be initiated by crosstalk in Ca2+-ROS pathway. Disclosures: No relevant conflicts of interest to declare.

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