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Cell Population Growth (cell + population_growth)
Selected AbstractsInduction of cell apoptosis in 3T3-L1 pre-adipocytes by flavonoids is associated with their antioxidant activityMOLECULAR NUTRITION & FOOD RESEARCH (FORMERLY NAHRUNG/FOOD), Issue 11 2006Chin-Lin Hsu Abstract Obesity is biologically characterized at the cellular level by an increase in the number and size of adipocytes differentiated from fibroblastic pre-adipocytes in adipose tissue. In this study, we focused on the relationship between the influence of flavonoids on cell population growth and their antioxidant activity. The results showed that the inhibition of flavonoids (naringenin, rutin, hesperidin, resveratrol, naringin and quercetin) on 3T3-L1 pre-adipocytes was 28.3, 8.1, 11.1, 33.2, 5.6 and 71.5%, respectively. In oxygen radical absorbance capacity (ORAC) assay, quercetin had the highest ORACROO value among the six flavonoids tested. Apoptosis assays showed that quercetin increased apoptotic cells in time- and dose-dependent manner. Treatment of cells with quercetin decreased the mitochondrial membrane potential in the courses of time and dose. The cell apoptosis/necrosis assay showed that quercetin increased the number of apoptotic cells, but not necrotic cells. Quercetin treatment of cells caused a significant time- and dose-dependent increase in the caspase-3 activity. Western analysis indicated that treatment of quercetin markedly down-regulated PARP and Bcl-2 proteins, and activated caspase-3, Bax, and Bak proteins. These results indicate that quercetin efficiently inhibits cell population growth and induction of apoptosis in 3T3-L1 pre-adipocytes. [source] Cell proliferation of human bone marrow mesenchymal stem cells on biodegradable microcarriers enhances in vitro differentiation potentialCELL PROLIFERATION, Issue 5 2010L.-Y. Sun Objectives:, For reasons of provision of highly-specific surface area and three-dimensional culture, microcarrier culture (MC) has garnered great interest for its potential to expand anchorage-dependent stem cells. This study utilizes MC for in vitro expansion of human bone marrow mesenchymal stem cells (BMMSCs) and analyses its effects on BMMSC proliferation and differentiation. Materials and methods:, Effects of semi-continuous MC compared to control plate culture (PC) and serial bead-to-bead transfer MC (MC bead-T) on human BMMSCs were investigated. Cell population growth kinetics, cell phenotypes and differentiation potential of cells were assayed. Results:, Maximum cell density and overall fold increase in cell population growth were similar between PCs and MCs with similar starting conditions, but lag period of BMMSC growth differed substantially between the two; moreover, MC cells exhibited reduced granularity and higher CXCR4 expression. Differentiation of BMMSCs into osteogenic and adipogenic lineages was enhanced after 3 days in MC. However, MC bead-T resulted in changes in cell granularity and lower osteogenic and adipogenic differentiation potential. Conclusions:, In comparison to PC, MC supported expansion of BMMSCs in an up-scalable three-dimensional culture system using a semi-continuous process, increasing potential for stem cell homing ability and osteogenic and adipogenic differentiation. [source] Ecology-based screen identifies new metabolites from a Cordyceps -colonizing fungus as cancer cell proliferation inhibitors and apoptosis inducersCELL PROLIFERATION, Issue 6 2009Y. Chen Objectives:, This study aims to identify new anti-cancer agents from Cordyceps -colonizing fungi, using an ecology-based approach. It also aims to explore their anti-cell proliferative mechanisms, and to evaluate their anti-tumour effects in vivo. Materials and methods:, Extracts from Cordyceps -colonizing fungi were tested on HeLa cells, and active extracts were separated to obtain anti-tumour metabolites; their structures were elucidated by mass and nuclear magnetic resonance spectroscopy. Cell cycle analysis was evaluated using flow cytometry. Tumour formation assays were performed using C57BL/6J mice. Results:, Based on ecological considerations, the selected extracts were subjected to initial anti-tumour screening. Bioassay-guided fractionation of the active extract afforded two new epipolythiodioxopiperazines, named gliocladicillins A (1) and B (2). (A) 1 and B (2) inhibited growth of HeLa, HepG2 and MCF-7 tumour cells. Further study demonstrated that both preparations arrested the cell cycle at G2/M phase in a dose-dependent manner, and induced apoptosis through up-regulation of expression of p53, p21, and cyclin B, and activation of caspases-8, -9 and -3. These data imply that gliocladicillins A (1) and B (2) induce tumour cell apoptosis through both extrinsic and intrinsic pathways. In addition, in vivo studies showed that they displayed significant inhibitory effects on cell population growth of melanoma B16 cells imlanted into immunodeficient mice. Conclusions:, Gliocladicillins A (1) and B (2) are effective anti-tumour agents in vitro and in vivo and should be further evaluated for their potential in clinical use. [source] 3- O -methylfunicone, a metabolite of Penicillium pinophilum, inhibits proliferation of human melanoma cells by causing G2 + M arrest and inducing apoptosisCELL PROLIFERATION, Issue 4 2009A. Baroni Objectives:, Melanoma cells take advantage of impaired ability to undergo programmed cell death in response to different external stimuli and chemotherapeutic drugs; this makes prevention of tumour progression very difficult. The aim of this study was to demonstrate whether 3- O -methylfunicone (OMF), a metabolite of Penicillium pinophilum, has the ability to arrest cell population growth and to induce apoptosis in A375P (parental) and A375M (metastasis derivatived) melanoma cell lines. Materials and methods:, Cell proliferation and apoptosis were analysed by flow cytometry, DNA fragmentation, caspase-3 and caspase-9 activation, and PARP-1 cleavage. Results:, We demonstrated that OMF affected cell proliferation in a time- and dose-dependent manner, reaching the best effect at concentration of 80 µg/ml for 24 h. Flow cytometry revealed that OMF caused significant G2 phase arrest, which was associated with marked decrease in cyclin B1/p34cdc2 complex and p21 induction. OMF also induced marked decrease of survivin expression. Reduced levels of apoptosis were evident after silencing p21 expression in both cell lines. Finally, the effect exercised by OMF on hTERT and TEP-1 gene expression confirmed the ability of this molecule to interfere with replicative ability of cells. Conclusions:, The results reported here seem to suggest that OMF as a promising molecule to include in strategies for treatment of melanoma. [source] In vitro polydeoxyribonucleotide effects on human pre-adipocytesCELL PROLIFERATION, Issue 5 2008E. Raposio Objectives: Adipose tissue is the most abundant and accessible source of adult stem cells. Human processed lipoaspirate contains pre-adipocytes that possess one of the a characteristic pathways of multipotent adult stem cells and are able to differentiate in vitro into mesenchymal and also neurogenic lineages. Because stem cells have great potential for use in tissue repair and regeneration, it would be significant to be able to obtain large amounts of these cells in vitro. As demonstrated previously, purine nucleosides and nucleotides mixtures can act as mitogens for several cell types. The aim of this study was to evaluate the effects of polydeoxyribonucleotides (PDRN), at appropriate concentrations, on human pre-adipocytes grown in a controlled medium, also using different passages, so as to investigate the relationship between the effect of this compound and cellular senescence, which is the phenomenon when normal diploid cells lose the ability to divide further. Materials and methods: Human pre-adipocytes were obtained by liposuction. Cells from different culture passages (P6 and P16) were treated with PDRN at different experimental times. Cell number was evaluated for each sample by direct counting after trypan blue treatment. DNA assay and the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide test were also carried out in all cases. Results and Conclusions: PDRN seemed to promote proliferation of human pre-adipocytes at both passages, but cell population growth increased in pre-adipocyte at P16, after 9 days as compared to control. Our data suggest that PDRN could act as a pre-adipocyte growth stimulator. [source] |