Study on Mechanisms of Telomerase Regulation in Arsenic Trioxide Inducing Apoptosis in Myelodysplasia Cell Line.

Blood ◽  
2004 ◽  
Vol 104 (11) ◽  
pp. 4706-4706
Author(s):  
Hongyan Tong ◽  
Jie Jin ◽  
Weilai Xu ◽  
Wenbin Qian ◽  
Maofang Lin
Keyword(s):  
Mrna Expression ◽  
Cell Line ◽  
Telomerase Activity ◽  
Time Dependent ◽  
Dependent Manner ◽  
Htert Gene ◽  
Binding Factor ◽  
Telomerase Regulation ◽  
Dose Dependent ◽  
Ttaggg Repeat

Abstract The telomerase activity can be down regulated by arsenic trioxide (As2O3), which is regarded as an apoptotic induction agent, is confirmed in many kinds of tumor cells. To investigate the mechanisms of telomerase regulation and to explore the correlation of As2O3 inducing apoptosis and telomerase regulation in MUTZ-1 cells, which are established as a high-risk myelodysplasia Cell line that derived from a MDS patient (FAB subtype refractory anemia with excess of blasts), a quantitative assessment of the telomerase activity by TRAP-ELISA and detection of the expression levels of hTERT, TRF1 (TTAGGG repeat binding factor 1), TRF2 (TTAGGG repeat binding factor 2), bcl-2, bax mRNA were performed, together with the assessment of the apoptosis by means of translocation of phosphatidylserine (PS) through flow cytometry assay. The results indicated that a typical apoptotic cell group distribution of DNA content was represented in the MUTZ-1 cells after being exposed to As2O3 at the range of concentration from 1μmol/L to 8μmol/L in a dose-dependent manner (r=0.736, P<0.001) and time-dependent manner (r=0.674, p<0.05), and the telomerase activity was down-regulated in a time-dependent manner (r=−0.976,P=0.024), and the expression level of hTERT mRNA in MUTZ-1 cells was represented in a dose-dependent manner (r=−0.892,P=0.042) and time-dependent manner (r=−1.000,P=0.04), after the cells were treated by As2O3 at the dosage as above. It was showed that a significant correlation between the decreased telomerase activity and the increased percentage of apoptotic cells in the treated cells (r=0.938,P=0.018), and there was a strong relationship between the telomerase activity and the mRNA expression of hTERT gene (r=0.783,P=0.022). However, As2O3 has no obvious effect on the expression level of TRF1 mRNA and TRF2 mRNA, which were regarded as two telomere-binding proteins. Further findings indicated that the inhibition of telomerase activity in MUTZ-1 cells was accompanied with down-regulated mRNA expression of bcl-2 gene (densitometry readings: 0.255±0.017 vs 0.466±0.069, P<0.05) and decreased ration of bcl-2/bax (densitometry reading ratios: 0.890±0.083 vs 0.546±0.014, P<0.05) at the dosage of 4μmol/L for 24 hours. These observations suggest that the apoptosis induced by As2O3 on MUTZ- 1 cells might be mediated through the inhibition of telomerase activity regulated by expression of hTERT gene, which implies that may be one of the mechanisms of As2O3 inducing apoptosis in MUTZ-1 cells.

Effects of Celecoxib on Human Acute Promyelocytic Leukemia Cell Line and Its Mechanism.

Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2851-2851
Author(s):  
Yun Xu ◽  
He Huang ◽  
Yanmin Zhao ◽  
Fenfang Zeng ◽  
Qian Zhou
Keyword(s):  
Cell Cycle ◽  
Cell Line ◽  
Fusion Gene ◽  
Telomerase Activity ◽  
Promyelocytic Leukemia ◽  
Time Dependent ◽  
Dependent Manner ◽  
Rt Pcr ◽  
Cycle Arrest ◽  
Cox 2

Abstract Acute promyelocytic leukemia (APL) is a special subtype of acute myelogenous leukemia (AML) which is characterized for a specific translocation between chromosome 15 and 17 [t(15;17)] and the expression of PML/RARα fusion gene. Celecoxib, one of the specific inhibitors of cyclooxygenase-2 (COX-2), has been reported to induce anti-neoplastic activity on many solid human tumor cell lines in recent years. In our study, ATRA resistant APL cell line MR2 cells were used to investigate the effects of celecoxib on hematological malignancy. MR2 cells were treated with celecoxib at different concentration (0, 20, 40, 80, 120 and 160μmol/L). The proliferation of MR2 cells was observed by MTT assay and apoptosis was detected by DNA fragmentation analysis and flow cytometry using Annexin V-FITC/PI staining. Western blot was used to detect the change of caspase-8, -9, -3 and PARP in MR2 cells. The expression of mRNA of fusion gene PML/RARα, COX-2 and survivin, bcl-2/bax, CIAP1 and CIAP2 was assessed by reverse transcription polymerase chain reaction (RT-PCR). Cell cycle analyzed by flow cytometry with PI staining and western blot was used to detect the expression of cell-cycle-regulating proteins. The telomerase activity of MR2 cells was analyzed by PCR-ELISA. The expression of hTERT mRNA and c-myc mRNA was assessed by RT-PCR. MR2 cells viability in presence of celecoxib decreased markedly in a dose- and time- dependent manner. After treated with celecoxib (20-160μmol/L) for 12-48h, the proliferation of MR2 cells were inhibited significantly, in comparison with the control group (P<0.01). 50% growth inhibition (IC50) at 24h and 48h was 80.93μmol/L and 71.72μmol/L, respectively. A DNA ladder pattern of internucleosomal fragmentation was observed. The translocation of phosphatidylserine at the outer surface of the cell plasma membrane could be induced by celecoxib and its level increased following the augmentation of the drug concentration. MR2 cells exposure to 40-160μmol/L celecoxib for 24h caused 9.59%, 24.00%, 36.10% apoptotic cells, which was more than that of the untreated group 2.84% (P<0.01). The expression of survivin mRNA decreased dramatically, while no significant change with PML/RARα and COX-2. Treatment with celecoxib for 24h resulted in the activation of caspase-3 and caspase-9, cleavage of PARP. 40-160μmol/L celecoxib led to cell cycle arrest in G1/S phase, and CyclinD1 and CyclinE decreased, accompanied with up-regulation of P21waf/cip1, P27KIP, P16INK4a. celecoxib could inhibit the telomerase activity of APL cell line, and the inhibition was dose- and time- dependent. The expression of hTERT mRNA and c-myc mRNA were down-regulated by celecoxib in dose- dependent manner. These results indicated that celecoxib could inhibit MR2 cells proliferation by inducing apoptosis, cell cycle arrest and suppression of telomerase activity.

scholarly journals Havachoobe (Onosma dichroanthum Boiss) Root Extract Decreases the Hepatitis B Virus Surface Antigen Secretion in the PLC/PRF/5 Cell Line

Intervirology ◽  
2020 ◽  
pp. 1-5
Author(s):  
Alireza Mohebbi ◽  
Fahimeh Azadi ◽  
Mohammad Mostakhdem Hashemi ◽  
Fatemeh Sana Askari ◽  
Nazanin Razzaghi
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Cell Line ◽  
Real Time ◽  
Real Time Pcr ◽  
Time Dependent ◽  
Root Extract ◽  
Dependent Manner ◽  
B Virus ◽  
Dose Dependent

<b><i>Background:</i></b> Many efforts are currently focused on functional treatment of the hepatitis B virus (HBV). This can be done by suppressing the secretion of HBV surface antigen (HBsAg). Scientific communities are very interested in natural products in that respect. <b><i>Objective:</i></b> Use of root extract of Havachoobe (<i>Onosma dichroanthum BoissI</i>), a Northern Iranian native medical herb, for assessment of its anti-HBsAg secretion activity. <b><i>Methods:</i></b> Havachoobe had been bought at a nearby apothecary store. Plant root extract was obtained using a hydroalcoholic process. Cytotoxic activity of the extract was examined on PLC/PRF/5 cells using MTT assay. ELISA has been used to measure HBsAg in the treated cell line supernatants. In addition, real-time PCR analysis was performed to evaluate the expression of HBsAg before and after treatment of Onosma in vitro. <b><i>Results:</i></b> The results showed very low root extract cytotoxicity at concentrations under 8 μg/mL. Tissue culture infectious dose 50 was obtained at 63.78 μg/mL. In a dose-dependent and time-dependent manner, a significantly reduced HBsAg secretion was observed at a concentration of 8 ppm at 12 h post-treatment. The real-time PCR result showed relative decreased HBsAg expression at all doses at 12 h post-treatment time. <b><i>Discussion:</i></b> In this study, we first reported anti-HBsAg activity on an Iranian herbal medicine. Havachoobe root extract was shown to be able to inhibit HBsAg in a dose-dependent and time-dependent manner. We find the extract exerts its inhibitory effect of HBsAg by targeting transcription of HBsAg.

scholarly journals The effect of micro-sized titanium dioxide on WM-266-4 metastatic melanoma cell line

2019 ◽  
Vol 19 (1) ◽  
pp. 60-66
Author(s):  
Tanja Prunk Zdravković ◽  
Bogdan Zdravković ◽  
Mojca Lunder ◽  
Polonca Ferk
Keyword(s):  
Titanium Dioxide ◽  
Mrna Expression ◽  
Metastatic Melanoma ◽  
Cell Line ◽  
Metabolic Activity ◽  
Melanoma Cell Line ◽  
Melanoma Cells ◽  
Time Dependent ◽  
Dependent Manner ◽  
Metastatic Melanoma Cell

Titanium dioxide (TiO2) is widely used as an inorganic UV-filter in cosmetic products; however, it has been classified as possibly carcinogenic to humans. While numerous studies demonstrated cytotoxic and genotoxic effects of nano-sized TiO2 in different cell lines, including human skin cells, studies investigating the effects of micro-TiO2 on human keratinocytes and melanocytes, in healthy and cancer cells, are scarce. Adenosine triphosphate (ATP) binding cassette subfamily B member 5 (ABCB5) is a plasma membrane protein known for its role in the tumorigenicity, progression, and recurrence of melanoma. Here, we investigated the effect of micro-TiO2 (average particle size ≤5 µm) on the metabolic activity, cytotoxicity and ABCB5 mRNA expression in metastatic melanoma cells. Metastatic melanoma cell line WM-266-4 was treated with different concentrations of micro-TiO2 for different incubation times to obtain dose- and time-dependent responses. Untreated WM-266-4 cells, cultured under the same conditions, were used as control. The cell metabolic activity was determined by MTT assay. Cytotoxicity of micro-TiO2 was analyzed by lactate dehydrogenase (LDH) cytotoxicity assay. The ABCB5 mRNA expression in melanoma cells was analyzed using quantitative reverse transcription polymerase chain reaction (RT-qPCR). After 120 hours of exposure to micro-TiO2 the metabolic activity of melanoma cells decreased, especially at the two highest micro-TiO2 concentrations. Comparably, the cytotoxicity of micro-TiO2 on melanoma cells increased after 48 and 120 hours of exposure, in a time-dependent manner. The ABCB5 mRNA expression in micro-TiO2-treated melanoma cells also decreased significantly after 24 and 48 hours, in a time-dependent manner. Overall, our results suggest inhibitory effects of micro-TiO2 on the metabolic activity and ABCB5 mRNA expression in metastatic melanoma cells, indicating its potential use as an anticancer agent.

scholarly journals Differential Regulation of Gonadotropin-Releasing Hormone (GnRH)I and GnRHII Messenger Ribonucleic Acid by Gonadal Steroids in Human Granulosa Luteal Cells

2003 ◽  
Vol 88 (2) ◽  
pp. 663-672 ◽  
Author(s):  
Shahram Khosravi ◽  
Peter C. K. Leung
Keyword(s):  
Mrna Expression ◽  
Time Course ◽  
Time Dependent ◽  
Transcriptional Level ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Maximum Increase ◽  
Luteal Cells ◽  
Messenger Ribonucleic Acid ◽  
Dose Dependent

In humans, reproduction was generally believed to be controlled by only one form of GnRH (called mammalian GnRH or GnRHI). However, recently, a second form of GnRH, analogous to chicken GnRHII, was discovered in several tissues, including the human ovary. The regulation and function of GnRHI in the hypothalamus has been well studied. However, the function and regulation of GnRHI, and particularly GnRHII in the ovary, is less well understood. Because gonadal sex steroids are one of the main regulators of reproduction, we investigated, in the present study, the regulation of GnRHI and GnRHII mRNA expression by 17β-estradiol (E2) and RU486 (a progesterone antagonist) in human granulosa luteal cells (hGLCs). The levels of the mRNA transcripts encoding the two GnRH forms were examined using semiquantitative RT-PCR followed by Southern blot analysis. With time in culture, GnRHI and GnRHII mRNA levels significantly increased, by 120% and 210%, at d 8 and d 1, respectively. The levels remained elevated until the termination of these experiments at d 10. A 24-h treatment of hGLCs with E2 (10−9 to 10−7m) resulted in a dose-dependent decrease and increase in mRNA expression of GnRHI and GnRHII, respectively. E2 (10−9m) significantly decreased GnRHI mRNA levels (by 55%) and increased GnRHII mRNA levels (by 294%). Time-course studies demonstrated that E2 (10−9m) significantly decreased GnRHI mRNA levels in a time-dependent manner, with maximal inhibition of 77% at 48 h. In contrast, GnRHII mRNA levels significantly increased in a time-dependent fashion, reaching a maximum level of 280% at 24 h. Cotreatment of hGLCs with E2 and tamoxifen (an E2 antagonist) reversed the inhibitory and stimulatory effects of E2 on the mRNA expression of GnRHI and GnRHII, respectively. Time- and dose-dependent treatment with RU486 did not affect GnRHI mRNA levels in hGLCs. In contrast, RU486 treatment significantly increased GnRHII mRNA levels in hGLCs in a time- and dose-dependent fashion, with a maximum increase being observed at 24 h (with 10−5m RU486). In summary, the present study demonstrated that the expression of GnRHI and GnRHII at the transcriptional level is differently regulated by E2 and P4 in hGLCs.

Ecological and physiological as well as biochemical properties of representatives of the Genus sedum L.

2014 ◽  
Vol 25 (3-4) ◽  
pp. 24-33
Author(s):  
O. I. Dzjuba ◽  
M. V. Yatsenko
Keyword(s):  
Nitric Oxide ◽  
Cell Line ◽  
Methanol Extract ◽  
Hepatoma Cell ◽  
Ethanol Extract ◽  
Biochemical Properties ◽  
Biologically Active ◽  
Hepatoma Cell Line ◽  
Dependent Manner ◽  
Dose Dependent

The article deals with the history of the study and the current state of research of physiological and biochemical properties of the plant genus Sedum that are useful for human and has been used in folk medicine for many years. It was noticed that antioxidant properties of extracts from plants S. sarmentosum, S. sempervivoides, S. takesimense were caused by the presence of phenolic compounds. Methanol extract of plants S. takesimense exhibited strong scavenging activities against 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radicals as well as significant inhibitory effects on lipid peroxidation and low density lipoprotein (LDL) oxidation induced by a metal ion Cu2+. Various immunomodulatory activities of various fractions of plants extracts (S. dendroideum, S. kamtschaticum, S. sarmentosum, S. telephium) are observed. It was shown that the ethanol extract of S. sarmentosum and it’s fractions suppressed specific antibody and cellular responses to ovalbumin in mice. The methanol extract of plants S. sarmentosum reduced the levels of anti-inflammatory markers, such as volume of exudates, number of polymorphonuclear leukocytes, suppressed nitric oxide synthesis in activated macrophages via suppressed induction of inducible nitric oxide synthase (iNOS). Polysaccharides fractions from plants S. telephium inducing productions of tumor necrosis factor alpha (TNF-α), increasing the intensity of phagocytosis in vitro and in vivo. Methanol extract from the whole part of S. kamtschaticum strongly inhibit PGE2 production from lipopolysaccharide-induced RAW 264.7 cells, a mouse macrophage cell line via modulating activity in gene expression of the enzyme cyclooxygenase-2 (COX-2). The methanol extract of plants S. sarmentosum and the major kaempferol glycosides from S. dendroideum have antinociceptive activity. It was noticed that anti-adipogenic activity of extracts from plants S. kamtschaticum were caused by inhibition of peroxisome-proliferator-activated receptor γ (PPARγ) expression and it’s dependent target genes, such as genes encoding adipocyte protein 2 (аР2), lipoprotein lipase (LPL), adiponectin and CD36. Polysaccharides fractions from S. telephium cause inhibition of cell adhesion of human fibroblast (MRC5) to laminin and fibronectin via interfere with integrin-mediated cell behaviour and they contributed to the role of polysaccharides in cell-matrix interaction. The methanol extract of plants S. sarmentosum exhibited a significant inhibitory activity in the chick embryo chorioallantoic membrane angiogenesis in a dose-dependent manner. The crude alkaloid fraction of S. sarmentosum caused a dose-dependent inhibition of cell proliferation on murine hepatoma cell line BNL CL.2 and human hepatoma cell line HepG2 without necrosis or apoptosis. Alkaloids from plants S. sarmentosum may improve survival of hepatoma patients via the inhibition of excessive growth of tumor cells. Plant’s juices have antiviral activity (S. sarmentosum, S. spurium, S. stahlii). Crude ethanol extract S. praealtum have spermicidal activity of the in mice and a relevant inhibitory effect of aqueous extract on human spermatozoa motility as well as an anti-fertilizing activity in rats. Hepatoprotective triterpenes, e.g., δ-amyrone, 3-epi-δ-amyrin, δ-amyrin and sarmentolin were isolated from S. sarmentosum. 2- and 2,6-substituted piperidine alkaloids (e.g., norsedamine, allosedridine, sedamine, allosedamine) are observed in plants S. acre, which in the presence of data on the use of pyridine and piperidine derivatives for treating neurodegenerative diseases (e.g., Alzheimer's disease), points on the promising research in this area. Taking into account that biologically active compounds are accumulated in the aboveground vegetative organs of plants of Sedum, the prospects of further study of the use of Sedum for the purposes of biotechnology and in the pharmaceutical industry becomes apparent. This work extends the existing views regarding the use of plants Sedum.

scholarly journals Induction of apoptosis by Kola nut extract as a recent and promising treatment strategy for Leukemia

Bionatura ◽  
2021 ◽  
Vol 6 (2) ◽  
pp. 1725-1732
Author(s):  
Hamdah Alsaeedi ◽  
Rowaid Qahwaji ◽  
Talal Qadah
Keyword(s):  
Cell Cycle ◽  
Cell Line ◽  
Leukemia Cell ◽  
K562 Cells ◽  
Myelogenous Leukemia ◽  
Time Dependent ◽  
Leukemia Cell Line ◽  
Apoptotic Cells ◽  
Dependent Manner ◽  
Anti Cancer

Kola nut extracts have recently been reported to contain chemopreventive compounds providing several pharmacological benefits. This study investigated Kola nut extracts' anti-cancer activity on human immortalized myelogenous leukemia cell line K562 through apoptosis and cell cycle arrest. Fresh Kola nuts were prepared as powder and dissolved in DMSO. Different concentrations (50, 100, 150, 200, and 250 μg/ml) of working solutions were prepared. The K562 cells were treated with the different concentrations of Kola nut extract or vehicle control (10% DMSO) followed by incubation at 37°C for 24, 48, and 72 hours, respectively. Treatment activity was investigated in K562 cells; by Resazurin, and FITC/Propidium Iodide and 7-AAD stained cells to evaluate apoptotic cells and the cell cycle's progression. Inhibition of leukemia cell proliferation was observed. The extract effectively induced cell death, early and late apoptosis by approximately 30% after 24 and 48 hours incubation, and an increase in the rate of dead cells by 50% was observed after 72 hours of incubation. Also, cell growth reduction was seen at high dose concentrations (150 and 200 µg/ml), as evident by cell count once treated with Kola nut extract. The total number of apoptotic cells increased from 5.8% of the control group to 27.4% at 250 µg/ml concentration. Moreover, Kola nut extracts' effects on K562 cells increased gradually in a dose and time-dependent manner. It was observed that Kola nut extracts could arrest the cell cycle in the G2/M phase as an increase in the number of cells by 29.8% and 14.6 % were observed from 9.8% and 5.2% after 24 and 48 hours of incubation, respectively. This increase was detected in a dose and time-dependent manner. Kola nut extracts can be used as a novel anti-cancer agent in Leukemia treatment as it has shown significant therapeutic potential and therefore provides new insights in understanding the mechanisms of its action. Keywords: Kola nut extracts, Leukemia, K562 cell line, Apoptosis, Cancer.

Inhibition of angiotensinogen production by angiotensin II analogues in human hepatoma cell line

1989 ◽  
Vol 257 (5) ◽  
pp. C888-C895 ◽  
Author(s):  
E. Coezy ◽  
I. Darby ◽  
J. Mizrahi ◽  
B. Cantau ◽  
M. H. Donnadieu ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Cell Line ◽  
Binding Sites ◽  
Inhibitory Effect ◽  
Hepatoma Cell Line ◽  
Dependent Manner ◽  
Human Hepatoma ◽  
Ang Ii ◽  
Hep G2 ◽  
Dose Dependent

The aim of this study was to examine in Hep G2, a human hepatoma-derived cell line, the presence of angiotensin II (ANG II) receptors and the effect of ANG II and its analogues on angiotensinogen production. The presence of ANG II receptors was demonstrated using a long-acting ANG II analogue, 125I-labeled [Sar1]ANG II. A single class of specific binding sites was identified in these cells with a dissociation constant (Kd) of 2 nM. The number and affinity of these binding sites were not changed by [Sar1]ANG II treatment over 24 h. ANG II showed an inhibitory effect on angiotensinogen production. [Sar1]ANG II also exhibited a similar inhibitory effect as that of ANG II but to a greater extent and therefore was used throughout these studies. [Sar1]ANG II inhibited angiotensinogen production in a dose-dependent manner, exhibiting a half-maximal inhibitory concentration (IC50) of 2 nM. Other ANG II analogues showed similar effects on angiotensinogen production. In order of decreasing ability, they were [Sar1]ANG II greater than [Sar1-Ala8]ANG II greater than [Sar1-Val8]ANG II greater than [Sar1-Val5-(Br5)-Phe8]ANG II greater than [Sar1-Val5-DPhe8]ANG II. Results of these studies show that the Hep G2 cell possesses specific ANG II receptors and that [Sar1]ANG II induces a dose-dependent inhibition of angiotensinogen production in this system.

scholarly journals The Effects of Apigenin-Biosynthesized Ultra-Small Platinum Nanoparticles on the Human Monocytic THP-1 Cell Line

Cells ◽  
2019 ◽  
Vol 8 (5) ◽  
pp. 444 ◽  
Author(s):  
Sangiliyandi Gurunathan ◽  
Muniyandi Jeyaraj ◽  
Min-Hee Kang ◽  
Jin-Hoi Kim
Keyword(s):  
Cell Line ◽  
Chemical Properties ◽  
Dependent Manner ◽  
Monocytic Cell ◽  
Monocytic Cell Line ◽  
Human Monocytic Cell Line ◽  
Physico Chemical ◽  
Proinflammatory Responses ◽  
Human Monocytic Cell ◽  
Dose Dependent

Generally, platinum nanoparticles (PtNPs) are considered non-toxic; however, toxicity depends on the size, dose, and physico-chemical properties of materials. Owing to unique physico-chemical properties, PtNPs have emerged as a material of interest for several biomedical applications, particularly therapeutics. The adverse effect of PtNPs on the human monocytic cell line (THP-1) is not well-established and remains elusive. Exposure to PtNPs may trigger oxidative stress and eventually lead to inflammation. To further understand the toxicological properties of PtNPs, we studied the effect of biologically synthesized ultra-small PtNPs on cytotoxicity, genotoxicity, and proinflammatory responses in the human monocytic cell line (THP-1). Our observations clearly indicated that PtNPs induce cytotoxicity in a dose-dependent manner by reducing cell viability and proliferation. The cytotoxicity of THP-1 cells correlated with an increase in the leakage of lactate dehydrogenase, generation of reactive oxygen species, and production of malondialdehyde, nitric oxide, and carbonylated proteins. The involvement of mitochondria in cytotoxicity and genotoxicity was confirmed by loss of mitochondrial membrane potential, lower ATP level, and upregulation of proapoptotic and downregulation of antiapoptotic genes. Decreases in the levels of antioxidants such as reduced glutathione (GSH), oxidized glutathione (GSH: GSSG), glutathione peroxidase (GPx), superoxide dismutase (SOD), catalase (CAT), and thioredoxin (TRX) were indicative of oxidative stress. Apoptosis was confirmed with the significant upregulation of key apoptosis-regulating genes. Oxidative DNA damage was confirmed by the increase in the levels of 8-oxodG and 8-oxoG and upregulation of DNA damage and repair genes. Finally, the proinflammatory responses to PtNPs was determined by assessing the levels of multiple cytokines such as interleukin-1β (IL-1β), IL-6, IL-8, tumor necrosis factor-α (TNF-α), granulocyte-macrophage colony-stimulating factor (GM-CSF), and monocyte chemoattractant protein 1 (MCP-1). All the cytokines were significantly upregulated in a dose-dependent manner. Collectively, these observations suggest that THP-1 cells were vulnerable to biologically synthesized ultra-small PtNPs.

scholarly journals Osteoblast differentiation of NIH3T3 fibroblasts is associated with changes in the IGF-I/IGFBP expression pattern

2006 ◽  
Vol 11 (4) ◽  
Author(s):  
Basem Abdallah
Keyword(s):  
Cell Line ◽  
Expression Pattern ◽  
Osteoblast Differentiation ◽  
Culture Conditions ◽  
Time Dependent ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Igf Binding Proteins ◽  
Igf System ◽  
Igf I

AbstractInsulin-like growth factors (IGFs) and IGF-binding proteins (IGFBPs) are essential regulators for osteoblast proliferation and differentiation. It has been reported that Dexamethasone (Dex), an active glucocorticoid (GC) analogue, synergizes the stimulatory effect of 1,25-dihydroxyvitamin D3 (1,25(OH)2D3) on osteoblast differentiation in the mouse fibroblastic cell line NIH3T3. I investigated whether this stimulatory effect is associated with changes in the expression pattern of the IGF/IGFBP system. Quantitative real-time PCR technology was used to quantify the gene expression levels of the IGF-system during osteoblast differentiation and in response to 1,25(OH)2D3 or Dex alone under serum-containing and serum-free culture conditions. Interestingly, NIH3T3 was shown to express high mRNA levels of IGF-I, IGF-II and IGFBP-5, and low levels of both IGFBP-2 and-6. During osteoblast differentiation (days 6-12), IGF-I mRNA was repressed by more than 60%, while the transcript of IGFBP-5 was markedly up-regulated, by more than 50-fold. Similarly, treatment with Dex alone resulted in a dose-and time-dependent increase in the expression of IGFBP-5 and a decrease in IGF-I mRNA. Treatment with 1,25(OH)2D3 alone increased the mRNA levels of IGF-I and IGFBP-6 by around 4-and 7-fold, respectively, in a dose-and time-dependent manner. In conclusion, my data demonstrated that osteoblast differentiation of NIH3T3 is associated with changes in the expression pattern of IGFs/IGFBPs, which are regulated by glucocorticoid in the presence of 1,25(OH)2D3. Modulation of the IGF/IGFBP levels by glucocorticoid might suggest important roles for the IGF-system in mediating the osteoblast differentiation of the NIH3T3 cell line.

scholarly journals A redox-based mechanism for induction of interleukin-1 production by nitric oxide in a human colonic epithelial cell line (HT29-Cl.16E)

1996 ◽  
Vol 313 (1) ◽  
pp. 35-38 ◽  
Author(s):  
Geneviève VALLETTE ◽  
Anne JARRY ◽  
Jean-Eric BRANKA ◽  
Christian L. LABOISSE
Keyword(s):  
Nitric Oxide ◽  
Epithelial Cell ◽  
Cell Line ◽  
Interleukin 1 ◽  
Epithelial Cell Line ◽  
Dependent Manner ◽  
Colonic Epithelial Cell ◽  
Colonic Epithelial Cell Line ◽  
Dose Dependent ◽  
Human Colonic Epithelial Cell

We evaluated the effects of two NO donors, sodium nitroprusside (SNP) and 3-morpholino-sydnonimine (SIN-1), characterized by alternative redox states, i.e. nitrosonium ion (NO+) and nitric oxide (NO•) respectively, on intracellular interleukin-1 (IL-1) production, by a human colonic epithelial cell line (HT29-Cl.16E). SNP was able to induce intracellular IL-1α production up to 10 h incubation, in a dose-dependent manner. Several experiments provide evidence that the NO+ redox form, and not the free radical NO•, is implicated in the IL-1α production: (i) SIN-1, devoid of any NO+ character, led to a very weak IL-1 production as compared with SNP; (ii) the reductive action of a thiol such as cysteine on NO+ led to a dose-dependent increase in NO• concentration, measured as NO2-/NO3- accumulation, and to a large decrease in IL-1 production. Dibutyryl cGMP had no effect on IL-1 production, this finding supporting the concept that a cGMP-independent pathway is involved in the intracellular signalling of NO+. Together these results point out that NO, depending on its redox form, is able to modulate IL-1 production in cultured colonic epithelial cells.

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