• Title/Summary/Keyword: apoptotic induction

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Induction of Apoptosis by Pectenotoxin-2 Isolated from Marine Sponges in U937 Human Leukemic Cells (인체 혈구암세포 U937에서 해양해면동물에서 추출된 Pectenotoxin-2에 의한 Apoptosis의 유발에 관한 연구)

  • Shin, Dong Yeok;Kang, Ho Sung;Bae, Song-Ja;Jung, Jee H.;Choi, Yung Hyun
    • Journal of Marine Bioscience and Biotechnology
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    • v.1 no.2
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    • pp.63-70
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    • 2006
  • Natural product compounds are the source of numerous therapeutic agents. The marine environment produces natural products from a variety of structural classes exhibiting activity against numerous disease targets including anticancer agents. Among these, pectenotoxin-2 (PTX-2), which was first identified as a cytotoxic entity in marine sponges, which depolymerizes actin filaments, was found to be highly effective and more potent to activate an intrinsic pathway of apoptosis in p53-deficient tumor cells compared to those with functional p53 both in vitro and in vivo. However, the anti-proliferative mechanism of the compound at non-cytotoxic concentrations has not yet been explored. In the current study, we sought to investigate anti-proliferation and apoptosis of PTX-2 against U937 human leukemic cells and its underlying molecular mechanism. Exposure of U937 cells to PTX-2 resulted in growth inhibition and induction of apoptosis in dose- and time-dependent manner as measured by MTT assay, fluorescent microscopy and flow cytometric analysis. The anti-proliferative effect of PTX-2 was associated with a marked increase in the expression of cyclin-dependent kinase p21 (WAF1/CIP1) mRNA which was tumor suppressor p53-independent. The increase in apoptosis was connected with a time-dependent down-regulation of anti-apoptotic Bcl-XL and inhibitor of apoptosis proteins (IAPs) family such as XIAP and cIAP-2. Though additional studies are needed, these findings suggested that PTX-2-induced inhibition of U937 cells was associated with the induction of apoptotic cell death and the results provided important new insights into the possible molecular mechanisms of the anti-cancer activity of PTX-2.

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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.

Induction of Apoptotic Cell Death by an Aqueous Extract of Cordyceps militaris in A549 Human Lung Carcinoma Cells (동충하초의 인체 폐암세포 증식억제에 관한 연구)

  • Hong Sang Hun;Kam Chul Woo;Park Dong-Il
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.18 no.4
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    • pp.1102-1106
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    • 2004
  • To investigate the anti-proliferative effects of an aqueous extract of Cordyceps militaris (AECM) on the growth of human lung carcinoma cell line A549, we performed various biochemical experiments such as the effects of AECM on the cell proliferation and viability, the morphological changes, the effects on expression of apoptosis and cell growth-regulatory gene products. Results obtained are as follow; AECM treatment declined the cell viability and proliferation of A549 cells in a concentration-dependent manner. The anti-proliferative effect by AECM treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. Taken together, these findings suggest that AECM-induced inhibition of human lung cancer cell proliferation is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products, and C. militaris may have therapeutic potential in human lung cancer.

High glucose diets shorten lifespan of Caenorhabditis elegans via ectopic apoptosis induction

  • Choi, Shin-Sik
    • Nutrition Research and Practice
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    • v.5 no.3
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    • pp.214-218
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    • 2011
  • Diets based on carbohydrates increase rapidly the blood glucose level due to the fast conversion of carbohydrates to glucose. High glucose diets have been known to induce many lifestyle diseases. Here, we demonstrated that high glucose diet shortened the lifespan of Caenorhabditis elegans through apoptosis induction. Control adult groups without glucose diet lived for 30 days, whereas animals fed 10 mg/L of D-glucose lived only for 20 days. The reduction of lifespan by glucose diet showed a dose-dependent profile in the concentration range of glucose from 1 to 20 mg/L. Aging effect of high glucose diet was examined by measurement of response time for locomotion after stimulating movement of the animals by touching. Glucose diet decreased the locomotion capacity of the animals during mid-adulthood. High glucose diets also induced ectopic apoptosis in the body of C. elegans, which is a potent mechanism that can explain the shortened lifespan and aging. Apoptotic cell corpses stained with SYTO 12 were found in the worms fed 10 mg/L of glucose. Mutation of core apoptotic regulatory genes, CED-3 and CED-4, inhibited the reduction of viability induced by high glucose diet, which indicates that these regulators were required for glucose-induced apoptosis or lifespan shortening. Thus, we conclude that high glucose diets have potential for inducing ectopic apoptosis in the body, resulting in a shortened lifespan accompanied with loss of locomotion capacity.

Fucoidan Extract from Laminaria religiosa Suppresses Ischemia-induced Apoptosis and Cell Proliferation in the Hippocampus of Gerbils

  • Lee, Jong-Jin;Song, Yun-Kyung;Lim, Hyung-Ho
    • The Journal of Korean Medicine
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    • v.27 no.4
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    • pp.105-115
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    • 2006
  • Fucoidan has been shown to exhibit a host of biological activities, including anti-coagulant, anti-thrombotic, anti-tumourigenic, anti-inflammatory, anti-viral, anti-complementary and neuroprotective effects. In the present study, we attempted to determine the effects of Fucoidan on both apoptosis and cell proliferation in the hippocampal CA1 region and the dentate gyrus of gerbils after the induction of transient global ischemia. This experiment involved the use of terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay as well as immunohistochemisty for caspase-3 and 5-bromo-2'-deoxyuridine (BrdU). The monosaccharide composition of the purified Fucoidan which had been extracted from Laminaria religiosa was utilized in this study. The present study clearly induces that apoptotic cell death and cell proliferation in the gerbil's hippocampal regions increased significantly following the induction of transient global ischemia and the results of this study also indicate that Fucoidan exerted a suppressive effect on this observed ischemia-induced increase in apoptosis within the CA1 and dentate gyrus, and also suppressed cell proliferation in the dentate gyrus.

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Induction of Apoptosis by Methanolic Extract of Rubia Cordifolia Linn in HEp-2 Cell Line is Mediated by Reactive Oxygen Species

  • Shilpa, P.N.;Sivaramakrishnan, V.;Devaraj, S. Niranjali
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2753-2758
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    • 2012
  • Rubia cordifolia Linn, which belongs to the Rubiaceae family, is a well-known herb used in Ayurvedic medicine. In the present study, we investigated the influence of a methanolic extract (RC) on the induction of apoptosis in HEp-2 (human laryngeal carcinoma) cell line, as evidenced by cytotoxicity, morphological changes and modification in the levels of pro-oxidants. Inhibition of cell proliferation and lactate dehydrogenase (LDH) release increased in a time and dose-dependent manner. Further, reduced glutathione (GSH), glutathione transferase (GST) and protein levels decreased and lipid peroxidation increased significantly on RC treatment in a dose dependent manner when compared to controls. Based on the results we determined the optimal dose as 30mg/ ml and the apoptotic effect of RC extract (30 mg/ml) on HEp-2 cells was confirmed by fluorescent microscopy and transmission electron microscopy (TEM) based on morphological and ultrastructural changes. RC extract suppressed the proliferation of HEp-2 oral cancer cells inducing apoptotic cell death in vitro. These results point to potential of RC extract as an agent for the treatment of laryngeal squamous cell carcinoma.

Fungal Taxol Extracted from Cladosporium oxysporum Induces Apoptosis in T47D Human Breast Cancer Cell Line

  • Raj, Kathamuthu Gokul;Sambantham, Shanmugam;Manikanadan, Ramar;Arulvasu, Chinnansamy;Pandi, Mohan
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.16
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    • pp.6627-6632
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    • 2014
  • Purpose: The present study concerns molecular mechanisms involved in induction of apoptosis by a fungal taxol extracted from the fungus Cladosporium oxysporum in T47D human breast cancer cells. Materials and Methods: Apoptosis-induced by the fungal taxol was assessed by MTT assay, nuclear staining, DNA fragmentation, flow cytometry and pro- as well as anti-apoptotic protein expression by Western blotting. Results: Our results showed inhibition of T47D cell proliferation with an $IC_{50}$ value of $2.5{\mu}M/ml$ after 24 h incubation. It was suggested that the extract may exert its anti-proliferative effect on human breast cancer cell line by suppressing growth, arresting through the cell cycle, increase in DNA fragmentation as well as down-regulation of the expression of NF-${\kappa}B$, Bcl-2 and Bcl-XL and up-regulation of pro-apoptotic proteins like Bax, cyt-C and caspase-3. Conclusions: We propose that the fungal taxol contributes to growth inhibition in the human breast cancer cell through apoptosis induction via a mitochondrial mediated pathway, with possible potential as an anticancer therapeutic agent.

Ginsenoside Rh2 Induces Apoptosis Independently of Bcl-2, Bcl-XL, or Bax in C6Bu-1 Cells

  • Kim, Young-Sook;Jin, Sung-Ha;Lee, You-Hui;Kim, Shin-Il;Park, Jong-Dae
    • Archives of Pharmacal Research
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    • v.22 no.5
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    • pp.448-453
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    • 1999
  • In ginsenoside Rh2-treated rat glioma C6Bu-1 cells, apoptotic morphological changes, such as cell shrinkage, chromatin condensation and pyknosis were confirmed by means of electron microscopy. To evaluate whether induction of apoptosis by ginsenoside Rh2 is mediated by the members of Bcl-2 family, we first established C6Bu-1 cells overexpressing Bcl-2. It was demonstrated that the expression of Bcl-2, Bcl-xL, and Bax was not altered in ginsenoside Rh2-treated C6Bu-1 overexpressing C6Bu-1 cells failed to prevent from ginsenoside Rh2-induced cell death. These results suggest the existence of other apoptotic pathway that requires induction of apoptosis by ginsenoside Rh2 rather than the pathway through Bcl-2, $Bcl-x_{L}$ or Bax in C6Bu-1 cells.

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Effects of Psidium guajava Leaf Extract on Apoptosis Induction Through Mitochondrial Dysfunction in HepG2 Cells

  • Nguyen, Van-Tinh;Ko, Seok-Chun;Oh, Gun-Woo;Heo, Seong-Yeong;Jung, Won-Kyo
    • Microbiology and Biotechnology Letters
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    • v.47 no.1
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    • pp.43-53
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    • 2019
  • The anticancer activity of guava (Psidium guajava L.) leaf extract (GLE) occurs via the induction of apoptosis in cancer cells. However, the mechanism behind GLE-induced apoptosis in the human hepatocellular carcinoma cell line HepG2 remains unclear. In the present study, we investigated the apoptotic effects and mechanism of action of GLE in cultured HepG2 cells. The results showed that GLE induced reactive oxygen species (ROS) synthesis and disrupted the mitochondrial membrane potential (${\Delta}{\Psi}m$). Moreover, GLE increased the expression of apoptotic pathway proteins, such as the cleaved forms of caspase-3, -8, and -9; the translocation of Bax and cytochrome c (cyt-c) from the mitochondria to the cytosol; and the downregulation of Bcl-2. In addition, p53 protein expression was increased upon GLE treatment. These observations indicate that the GLE-induced apoptosis in HepG2 cells is mediated by mitochondrial ROS generation, followed by caspase activation and cyt-c release, suggesting that GLE may be a promising candidate for the development of novel drugs for the treatment of liver cancers.

Apoptosis of Human Lung Carcinoma Cells through the Inhibition of Bcl-2 Expression and Activation of Caspase by Chungjogupae-tang (인체폐암세포에서 Bcl-2 발현저하 및 caspase 활성을 통한 청조구폐탕의 apoptosis 유발에 관한 연구)

  • Cho, In-Joo;Gam, Chul-Woo;Kim, Ki-Tak;Park, Dong-Il
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.21 no.1
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    • pp.93-97
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    • 2007
  • We previously reported the anti-proliferative effect of Chungjogupae-tang (CJGPT) in human lung carcinoma A549 cells, which was associated with the induction of cyclin-dependent kinase inhibitor p21 in a tumor suppressor p53-independent manner. CJGPT treatment also resulted in the inhibition of prostaglandin E2 release A549 cells by the down-regulation of cyclooxygenase-2. In the present study, we investigated the pathway of the induction of apoptotic cell death by CJGPT in A549 cells. It was found that CJGPT could inhibit the cell viability and induce the apoptotic cell death of A549 cells in a dose-dependent manner as measured by hemocytometer counts, flow cytometry analysis and agarose gel electrophoresis. Apoptosis of A549 cells by CJGPT was associated with a down-regulation of anti-apoptotic Bcl-2 and inhibitor of apoptosis proteins (IAPs) expression. Additionally, DNA fragmentation by CJGPT was connected with the activation of inhibitor of caspase-activated DNase/DNA fragmentation factor 45 (ICAD/DFF45) protein expression.