88 research outputs found
Methionine affects the expression of pluripotency genes and protein levels associated with methionine metabolism in adult, fetal, and cancer stem cells
No full textIntracellular and extracellular regulatory factors promote the potency and self-renewal property of stem cells. Methionine is fundamental for protein synthesis and regulation of methylation reactions. Specifically, methionine metabolism in embryonic and fetal development processes regulates gene expression profile/epigenetic identity of stem cells to achieve pluripotency and cellular functions. We aimed to reveal the differences in methionine metabolism of bone marrow (BM)-mesenchymal stem cells (MSCs), umbilical cord blood (UCB)-MSCs, and cancer stem cells (CSCs), which reflect different metabolic profiles and developmental stages of stem cells. UCB-MSC, BM-MSCs, and breast CSCs were treated with different doses (0, 10, 25, 50, and 100 mu M) of l-methionine. Cell surface marker and cell cycle assessment were performed by flow cytometry. Changes in gene expressions (OCT3/4, NANOG, DMNT1, DNMT3A, and DNMT3B, MAT2A, and MAT2B) with methionine supplementation were examined by quantitative real-time polymerase chain reaction and the changes in histone methylation (H3K4me3, H3K27me3) levels were demonstrated by western blot analysis. S-adenosylmethionine//S-adenosylhomocysteine (SAM/SAH) levels were evaluated by enzyme-linked immunosorbent assay. Cells that were exposed to different concentrations of l-methionine, were mostly arrested in the G0/G1 phase for each stem cell group. It was evaluated that BM-MSCs increased all gene expressions in the culture medium-containing 100 mu M methionine, in addition to SAM/SAH levels. On the other hand, UCB-MSCs were found to increase OCT3/4, NANOG, and DNMT1 gene expressions and decrease MAT2A and MAT2B expressions in the culture medium containing 10 mu M methionine. Moreover, an increase was observed in the He3K4me3 methylation profile. In addition, OCT3/4, NANOG, DNMT1, and MAT2B gene expressions in CSCs increased starting from the addition of 25 mu M methionine. An increase was determined in H3K4me3 protein expression at 50 and 100 mu M methionine-supplemented culture condition. This study demonstrates that methionine plays a critical role in metabolism and epigenetic regulation in different stem cell groups
Does N-Acetyl Cysteine Protect Against Apoptosis in HL60 Cell Line?
No full textObjectives: The primary objective of this study is to determine the role of glutathione depletion and N-acetylcysteine on apoptotic signal formation in HL60 cell line
Ritonavir nanosuspensions prepared by microfluidization with enhanced solubility and desirable immunological properties
No full text© 2022 Informa UK Limited, trading as Taylor & Francis Group.The objective of this study was to develop ritonavir (RTV) nanosuspensions (NSs) by microfluidization method. Particle size (PS) measurements were performed by photon correlation spectroscopy. Amorphous properties of the particles were evaluated by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The dissolution studies were conducted in fed state simulated intestinal fluid (FeSSIF) medium. The flow cytometry was utilized to determine the lymphocyte sub-groups and immune response of NSs. RTV NSs were obtained with 400–500 nm PS. The crystal properties of RTV remain unchanged. The solubility of NS was enhanced five times. 57% and 18% of RTV were dissolved in FeSSIF medium for NSs and coarse powder. According to immunological studies, the prepared NSs did not significantly alter the ratio of CD4+/CD8+. Therefore, NSs may be a beneficial approach for the oral administration of RTV
Effects of gamma irradiation on cell cycle, apoptosis and telomerase activity in p53 wild-type and deficient HCT116 colon cancer cell lines
No full textWater-soluble green perylenediimide (PDI) dyes as potential sensitizers for photodynamic therapy
No full textA series of water-soluble green perylenediimide (PDI) dyes have been synthesized. On red light excitation, these dyes were shown to be efficient generators of singlet oxygen, and in cell culture media, they were shown to display significant light-induced cytotoxic effects on the human erythroleukemia cell line (K-562). It appears that highly versatile PDI dyes are likely to find new applications in photodynamic therapy
Correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic images in lymphoma patients
No full textThe purpose of this study was to determine the correlation of flow cytometric parameters and transferrin receptors with gallium-67 scintigraphic imaging results in Hodgkin's and non-Hodgkin's lymphoma patients. DNA content and cell cycle analyses were performed using flow cytometry and transferrin receptor analysis was carried out by the immunohistochemistry technique in 24 patients aged between 16 and 62 years. All patients underwent gallium-67 scintigraphy, and tumour to background ratios were calculated. The findings were correlated with computed tomography and/or magnetic resonance imaging. A strong relationship was observed between flow cytometry and transferrin receptor expression with gallium-67 tumour scintigraphy [P = 0.005, r = 0.054 and P = 0.038, r = 0.54 (Spearman test), respectively]. The results of this study show that there is a close correlation between each of these modalities and, as they reflect the biological activity of the tumour, together they have a major role in treatment and follow-up. ((C) 2000 Lippincott Williams & Wilkins)
Comparison Of Phototoxic Effects Of Hypericin-Mediated Photodynamic Therapy In Ht-29 And Caco-2 Colon Cancer Cells
No full textHypericin (HYP) is a plant-derived photosensitizer. HYP is preferentially taken up by tumor cells. We designed this study to compare HYP-mediated photodynamic therapy (PDT) in HT-29 and Caco-2 colon cell lines. Cells were treated with 0.04, 0.08, and 0.15 mu M HYP concentrations and irradiated. The effect of HYP on metabolic profiles, alterations in lactate dehydrogenase (LDH) leakage, and cell cycle progression was investigated for the first time. Changes in glucose consumption, lactate production, and LDH leakage were analyzed. HYP-induced cell death was quantified by double staining (acridine orange/propidium iodide) and alterations in cell cycle regulation were analyzed with flow cytometry (using propidium iodide). LDH leakage and the number of dead cells were elevated, and glucose consumption and lactate production decreased in a dose-and time-dependent manner. PDT resulted in an induction of apoptosis, mostly at the 0.08 mu M HYP concentration. Apoptosis and/or necrosis were increased in the 0.15 mu M HYP group. The accumulation of cells in the G2/M phase might account for the growth inhibition in HT-29 and Caco-2 cells with 0.08 mu M HYP photoactivation. The observed G2/M arrest suggested that HYP may slow down the growth of colon cancer cells by regulating the cell cycle, leading either to growth inhibition or to initiation of apoptotic pathways.WoSScopu
Toll-like receptors 2 and 4 cell surface expression reflects endotoxin tolerance in Henoch-Schönlein purpura.
No full textGastric lymphomas in Turkey - Analysis of prognostic factors with special emphasis on flow cytometric DNA content
No full textBACKGROUND. In contrast to DNA ploidy, to the authors' knowledge the prognostic significance of S-phase fraction (SPF) in gastric lymphomas has not been determined. In the current study, the prognostic significance of various parameters including SPF and DNA aneuploidy were analyzed and some distinct epidemiologic and biologic features of gastric lymphomas in Turkey were found
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