• Title/Summary/Keyword: condensation of DNA

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Involvement of ${\beta}$-Lactamase Inhibitory Protein, BLIP-II, in Morphological Differentiation of Streptomyces exfoliatus SMF19

  • Kim, Eun-Sook;Song, Ju-Yeon;Kim, Dae-Wi;Ko, Eun-Ji;Jensen, Susan E.;Lee, Kye-Joon
    • Journal of Microbiology and Biotechnology
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    • v.18 no.12
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    • pp.1884-1889
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    • 2008
  • The ${\beta}$-lactamase inhibitory protein, BLIP-II, found in the culture supernatant of Streptomyces exfoliatus SMF19, shows no discernible sequence identity with other ${\beta}$-lactamase inhibitory proteins identified in Streptomyces spp. A null mutant of the gene encoding BLIP-II (bliB::$hyg^r$) showed a bald appearance on solid media. Although BLIP-II was initially isolated from the supernatant of submerged cultures, sites of BLIP-II accumulation were seen in the cell envelope. Mutation of bliB was also associated with changes in the formation of septa and condensation of the chromosomal DNA associated with sporulation. The bliB mutant exhibited infrequent septa, showing dispersed chromosomal DNA throughout the mycelium, whereas the condensed chromosomes of the wild-type were separated by regularly spaced septa giving the appearance of a string of beads. Therefore, on the basis of these results, it is suggested that BLIP-II is a regulator of morphological differentiation in S. exfoliatus SMF19.

Zinc-induced Apoptosis in C6 glial Cells via Generation of Hydrogen Peroxide($H_2O_2$) (신경교세포주 C6 glial에서 Zinc의 Hydrogen Peroxide($H_2O_2$) 생성을 통한 세포고사)

  • 이지현;김명선;소흥섭;김남송;조광호;이향주;이기남;박길래
    • Toxicological Research
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    • v.16 no.3
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    • pp.179-185
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    • 2000
  • Zinc is known to generate reactive oxygen species (ROS) including superoxide anion and hydrogen peroxide ($H_2O_2$), which eventually contribute to cytotoxicity in a variety of cell types. Here in, we demonstrated that zinc decreased the viability of C6 glial cells in a time and dose-dependent manner, which was revealed as apoptosis characterized by ladder-pattern fragmentation of genomic DNA. chromatin condensation and DNA fragmentation in Hoechst dye staining. Zinc-induced apoptosis of C6 glial cells was prevented by the addition of catalase and antioxidants including reduced glutathione (GSH), N-acetyl-L-cysteine (NAC) and pyrrolidinedithiocarbamate (PDTC). Wefurther confirmed that zinc decreased intrac-ellular levels of GSH and generated $H_2O_2$in C6 glial cells. Moreover, antioxidants also decreased the generation of zinc-induced $H_2O_2$ in C6 glial cells. These data indicated that zinc-induced the apoptotic death of C6 glial cells via generation of reactive oxygen species such as $H_2O_2$.

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The effect of vitamin C on the gene expression profile of sperm protamines in the male partners of couples with recurrent pregnancy loss: A randomized clinical trial

  • Hamidian, Saeideh;Talebi, Ali Reza;Fesahat, Farzaneh;Bayat, Mohammad;Mirjalili, Ali Mohammad;Ashrafzadeh, Hamid Reza;Rajabi, Mahya;Montazeri, Fateme;Babaei, Saeid
    • Clinical and Experimental Reproductive Medicine
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    • v.47 no.1
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    • pp.68-76
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    • 2020
  • Objective: Since sperm abnormalities are known to be a major reason for recurrent pregnancy loss (RPL), any defects in DNA structure and chromatin condensation can place embryos at risk in the early stage of development and implantation. As antioxidants such as vitamin C may play a protective role against the destruction of protamine genes in sperm chromatin, this study was conducted to evaluate the effects of vitamin C on chromatin and the expression of protamine genes in the male partners of couples with RPL. Methods: Twenty male partners of couples with RPL were selected as the intervention group and received vitamin C supplementation (250 mg daily for 3 months). Healthy fertile men (n = 20) were included as controls. Sperm chromatin, DNA integrity, and the expression levels of protamine genes were evaluated before and after treatment. Results: Significant differences were found in sperm morphology, protamine deficiency, and apoptosis between the two groups and before and after vitamin C administration. A significant change was found in mRNA levels of PRM1, PRM2, and the PRM1/PRM2 ratio after treatment. Conclusion: Daily oral administration of vitamin C may improve human sperm parameters and DNA integrity by increasing protamine gene expression levels in the male partners of couples with RPL. The beneficial effects of vitamin C supplementation as an antioxidant for the male partners of couples with RPL could lead to improved pregnancy outcomes in these cases.

Mechanism Underlying NaF-Induced Apoptosis in Human Oral Squamous Cell Carcinoma

  • Hur, Young-Joo;Kim, Do-Kyun;Lee, Seung-Eun;Kim, In-Ryoung;Jeong, Na-Young;Kim, Ji-Young;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.35 no.2
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    • pp.51-60
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    • 2010
  • Few studies have evaluated the apoptosis-inducing efficacy of NaF on cancer cells in vitro but there has been no previous investigation of the apoptotic effects of NaF on human oral squamous cell carcinoma cells. In this study, we have investigated the mechanisms underlying the apoptotic response to NaF treatment in the YD9 human squamous cell carcinoma cell line. The viability of YD9 cells and their growth inhibition were assessed by MTT and clonogenic assays, respectively. Hoechst staining, DNA electrophoresis and TUNEL staining were conducted to detect apoptosis. YD9 cells were treated with NaF, and western blotting, immunocytochemistry, confocal microscopy, FACScan flow cytometry, and MMP and proteasome activity assays were performed sequentially. The NaF treatment resulted in a time- and dose-dependent decrease in YD9 cell viability, a dose-dependent inhibition of cell growth, and the induction of apoptotic cell death. The apoptotic response of these cells was manifested by nuclear condensation, DNA fragmentation, the reduction of MMP and proteasome activity, a decreased DNA content, the release of cytochrome c into the cytosol, the translocation of AIF and DFF40 (CAD) into the nucleus, a significant shift of the Bax/Bcl-2 ratio, and the activation of caspase-9, caspase-3, PARP, Lamin A/C and DFF45 (ICAD). Furthermore, NaF treatment resulted in the downregulation of G1 cell cyclerelated proteins, and upregulation of p53 and the Cdk inhibitor $p27^{KIP1}$. Taken collectively, our present findings demonstrate that NaF strongly inhibits YD9 cell proliferation by modulating the expression of G1 cell cycle-related proteins and inducing apoptosis via mitochondrial and caspase pathways.

Mechanism Underlying Shikonin-induced Apoptosis and Cell Cycle Arrest on SCC25 Human Tongue Squamous Cell Carcinoma Cell Line

  • Oh, Sang-Hun;Park, Sung-Jin;Yu, Su-Bin;Kim, Yong-Ho;Kim, In-Ryoung;Park, Bong-Soo
    • International Journal of Oral Biology
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    • v.40 no.1
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    • pp.51-61
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    • 2015
  • Shikonin, a major ingredient in the traditional Chinese herb Lithospermumerythrorhizon, exhibits multiple biological functions including antimicrobial, anti-inflammatory, and antitumor effects. It has recently been reported that shikonin displays antitumor properties in many cancers. This study was aimed to investigate whether shikonin could inhibit oral squamous carcinoma cell (OSCC) growth via mechanisms of apoptosis and cell cycle arrest. The effects of shikonin on the viability and growth of OSCC cell line, SCC25 cells were assessed by MTT assay and clonogenic assays, respectively. Hoechst staining and DNA electrophoresis indicated that the shikonin-treated SCC25 cells were undergoing apoptosis. Western blotting, immunocytochemistry, confocal microscopy, flow cytometry, MMP activity, and proteasome activity also supported the finding that shikonin induces apoptosis. Shikonin treatment of SCC25 cells resulted in a time- and dose-dependent decrease in cell viability, inhibition of cell growth, and increase in apoptotic cell death. The treated SCC25 cells showed several lines of apoptotic manifestation as follows: nuclear condensation; DNA fragmentation; reduced MMP and proteasome activity; decrease in DNA contents; release of cytochrome c into cytosol; translocation of AIF and DFF40 (CAD) onto the nuclei; a significant shift in Bax/Bcl-2 ratio; and activation of caspase-9, -7, -6, and -3, as well as PARP, lamin A/C, and DFF45 (ICAD). Shikonin treatment also resulted in down-regulation of the G1 cell cycle-related proteins and up-regulation of $p27^{KIP1}$. Taken together, our present findings demonstrate that shikonin strongly inhibits cell proliferation by modulating the expression of the G1 cell cycle-related proteins, and that it induces apoptosis via the proteasome, mitochondria, and caspase cascades in SCC25 cells.

Apoptosis Induction of HCT-15 Cells by Extracts of Undaria pinnatifida with Fermented Micro-organism (미역 발효추출물의 HCT-15 대장암 세포 사멸 유도 효과)

  • Kim, Tae-Yun;Han, Hyo-Sang;Lee, Young-Jong
    • The Korea Journal of Herbology
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    • v.28 no.4
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    • pp.33-40
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    • 2013
  • Objectives : To study the apoptosis effects of fermented Undaria pinnatifida extracts(FUP) against HCT-15 colon cancer cells. Method : By measuring cell proliferation, DNA fragmentation, cell cycle, morphology, and western blot from FUP, the study investigated the effects of the extractions had upon the HCT-15 colon cancer cells, and concluded that the inhibiting effects upon cells were induced by apoptosis. Result : FUP effectively inhibited the growth of HCT-15 colon cancer cells. After analyzing the DNA fragmentation, the study observed a DNA ladder, while examining the cells, and found an increase of sub-G1 hypodiploid cells. On the changes regarding the nucleus of the cells, a condensation of cells and chromatin, as well as an apoptotic body was clearly observed. By observing through western blot from FUP, the study found a decreased level of Bcl-2 from HCT-15 colon cancer cells, but the increased level of Bax and cleaved caspase-3, which as a result induced apoptosis, inhibiting the growth of HCT-15 colon cancer cells. FUP increased the natural death of HCT-15 colon cancer cells by the induction of apoptosis. FUP seemed to have no suppressing effect upon HL-60/MX2 cells. However, compared to the fucoidan, the study was able to clearly observe morphological changes of HCT-15 cells apoptosis, in a 1/2 concentration. Conclusion : FUP had antiproliferative effects on different kinds of cancer cells, while proving especially efficacious against colon cancer cells.

Effects of LED irradiation on the expression of apoptosis-related molecules in human SH-SY5Y neuroblastoma cells

  • Cho, Kyu-Seung;Ryu, Sun-Youl;Choi, Hong-Ran
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.33 no.1
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    • pp.1-10
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    • 2007
  • To verify the inhibitory or protective effects of light-emitting diode(LED) irradiation on apoptotic cell death induced by $CoCl_2$, human SH-SY5Y cells were treated with $CoCl_2$ and LED were used to irradiate the cells. In the cell viability assay, cells were died slowly from $50{\mu}M$ to $250{\mu}M$ and about 50% of cells died after 12 hours at $400{\mu}M$ of $CoCl_2$. The Diff-Quik staining revealed that cells showed condensation of DNA and blebbing of the cell membrane. The DNA fragmentation assay revealed the DNA fragmentation, which is another apoptosis marker, occurred in cells treated with $400{\mu}M$ $CoCl_2$ for 16 hours. In the western blot for HIF-$1{\alpha}$, HIF-$1{\alpha}$ was expressed after 3 hours from induction and peaked maximally at 16 hours. In the cell viability assay of the effects of LED irradiation (at 590 nm for 1 hour 20 minutes), the cells showed more proliferation (about 20%) than the control group. The RPA assay of various apoptosis-related molecules showed that pro-apoptosis molecules such as Bax, Bak, and Bid were upregulated in the $CoCl_2$ treatment group. This means that the apoptotic cell population was increased. However there was some significant changes in LED irradiated cells. In the $CoCl_2$-treated LED irradiation group, those molecules were down-regulated more than in the only $CoCl_2$-treated group. These results have shown that $CoCl_2$ may induce apoptotic cell death in human SH-SY5Y neuroblastoma cells. And LED irradiation has a positive effect on apoptotic cells by down-regulation of pro-apoptotic molecules.

Effect of WHW, a polyherbal medicine for the treatment of chronic renal failure on staurosporin-induced apotosis in MDCK cells (만성신부전 한약제제 WHW의 신장세포에서의 Staurosporine 유도 세포사멸에 대한 억제 효과)

  • Bae, Hyo-Sang;Yoon, Cheol-Ho;Park, Yong-Ki
    • The Korea Journal of Herbology
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    • v.27 no.4
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    • pp.45-51
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    • 2012
  • Objectives : WHW is a polyherbal medicine for the treatment of chronic renal failure (CRF). WHW previously reported various biological property such as anti-inflammation, anti-oxidation and anti-renal fibrosis in CRF. This study aimed to investigate the anti-apoptotic effect of WHW on staurosporin(SSP)-induced apoptosis in canine kidney epithelial cells (MDCK). Methods : MDCK cells were treated with different concentrations of WHW (0.1, 0.2, 0.5 and $1mg/m{\ell}$) for 1 h, and then induced apoptosis by treatment of SSP ($1{\mu}M$) for 24 h. Cell viability was measured by WST-1 assay. The expression of apoptotic proteins such as caspase-3, Bax and Bcl-2 was determined by Western blot. Caspase-3 activity and ROS levels were also measured by their commercial available assay kits. Cell apoptosis was observed by Hoechst and DNA fragmentation. Results : WHW significantly increased the cell viability on SSP-treated MDCK cells. WHW inhibited SSP-induced expression of apoptotic proteins such as caspase-3 and Bax, and significantly decreased caspase-3 activity in MDCK cells. WHW significantly decreased SSP-induced production of ROS, and suppressed SSP-induced chromatin condensation and DNA fragmentation in MDCK cells. Conclusions : These results suggest that WHW has an anti-apoptotic effect in renal cells through suppressing the expression of apoptotic proteins, ROS production and DNA damages.

TPA-and $H_2O_2$- induced Apoptosis by Epigenetic Mechanism and Preventive Effect of L-Carnosine on TPA- and $H_2O_2$- induced Apoptosis of v-myc Transformed Rat Liver Epithelial Cells

  • Kang, Kyung-Sun;Yun, Jun-Won;Cho, Sung-Dae;Lee, Yong-Soon
    • Proceedings of the Korean Society of Toxicology Conference
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    • 2001.05a
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    • pp.22-40
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    • 2001
  • Apoptosis is characterized by DNA fragmentation, chromatin condensation and plasma membrane blebbing. These apoptotic processes have been mainly associated with genetic mechanisms. Recently, these processes have been also associated with mitochondrial events that include the release of cytochrome c and Diablo/SMAC by modulation of mitochondrial membrane permeability.(omitted)

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The Preventive Effects of Bcl-2 and $Bcl-_{XL}$ on Lovastatin-induced Apoptosis of C6 Glial Cells

  • Choi, Jae-Won;Lee, Jong-Min;Oh, Young-Jun
    • The Korean Journal of Physiology and Pharmacology
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    • v.6 no.5
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    • pp.235-239
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    • 2002
  • It has been reported that lovastatin induced cell death and suppressed proliferation in various cell lines. In this study, we examined whether the cytotoxic effects of lovastatin could be prevented by Bcl-2 or $Bcl-_{XL}$ in C6 glial cells. Overexpression of human Bcl-2 or $Bcl-_{XL}$ prevented lovastatin $(25{\mu}M)-induced$ changes such as DNA fragmentation, chromatin condensation, disruption of cell membrane, and cleavage of poly (ADP-ribose) polymerase. Lovastatin-induced inhibition of cell proliferation was unaffected by Bcl-2 or $Bcl-_{XL}$ overexpression. These results suggest that Bcl-2 and $Bcl-_{XL}$ can prevent lovastatin-induced apoptosis in C6 glial cells, though the inhibition of proliferation remains unaffected by these proteins.