• Nutrition Research and Practice
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• 제8권2호
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• pp.132-137
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• 2014

BACKGROUND/OBJECTIVES: In this study, the apoptogenic activity and mechanisms of cell death induced by hexane extract of aged black garlic (HEABG) were investigated in human leukemic U937 cells. MATERIALS/METHODS: Cytotoxicity was evaluated by MTT (3-(4, 5-dimethyl-thiazol-2-yl)-2, 5-diphenyl tetrazoliumbromide) assay. Apoptosis was detected using 4,6-diamidino-2-phenyllindile (DAPI) staining, agarose gel electrophoresis and flow cytometry. The protein levels were determined by Western blot analysis. Caspase activity was measured using a colorimetric assay. RESULTS: Exposure to HEABG was found to result in a concentration- and time-dependent growth inhibition by induction of apoptosis, which was associated with an up-regulation of death receptor 4 and Fas legend, and an increase in the ratio of Bax/Bcl-2 protein expression. Apoptosis-inducing concentrations of HEABG induced the activation of caspase-9, an initiator caspase of the mitochodrial mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly(ADP-ribose)-polymerase. HEABG also induced apoptosis via a death receptor mediated extrinsic pathway by caspase-8 activation, resulting in the truncation of Bid, and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. However, pre-treatment of U937 cells with the caspase-3 inhibitor, z-DEVD-fmk, significantly blocked the HEABG-induced apoptosis of these cells, and increased the survival rate of HEABG-treated cells, confirming that HEABG-induced apoptosis is mediated through activation of caspase cascade. CONCLUSIONS: Based on the overall results, we suggest that HEABG reduces leukemic cell growth by inducing caspase-dependent apoptosis through both intrinsic and extrinsic pathways, implying its potential therapeutic value in the treatment of leukemia.

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.950-956
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• 2002

The antitumor activity of the insect pathogenic fungus Paecilomyces japonica has been attributed to apoptotic cell death. However, the mechanism underlying the induced apoptosis has not yet been elucidated. In this study, we for the first time show that mitochondria-dependent caspase-3 activation were associated with the apoptotic activity of P. japonica in human acute leukemia Jurkat T cells. When Jurkat T cells were treated with the ethyl acetate extract of P japonica at concentrations ranging from $2-6{\mu}g/ml$, apoptotic cell death. accompanied by several biochemical events such as caspase-9 activation, caspase-3 activation, degradation of poly (ADP-ribose) polymerase (PARP), and apoptotic DNA fragmentation, was induced in a dose-dependent manner. In addition, the release of cytochrome c from mitochondria was detected. Under these conditions, the expression of Fas and Fas-ligand (FasL) remained unchanged. Ethyl acetate extract-induced mitochondrial cytochrome c release, caspase-3 activation, PARP cleavage, and apoptotic DNA fragmentation were suppressed by the ectopic expression of Bcl-2, which is known to block mitochondrial cytochrorme c release. Accordingly, these results demonstrate that P. japonica-induced apoptotic cell death is mediated by a cytochrome c-dependent caspase-3 activation pathway that can be interrupted by Bcl-2.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.334-342
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• 2015

4-O-Methylhonokiol (MH), a bioactive compound derived from Magnolia officinalis, is known to exhibit antitumor effects in various cancer cells. However, the precise mechanism of its anticancer activity in cervical cancer cells has not yet been studied. In this study, we demonstrated that MH induces apoptosis in SiHa cervical cancer cells by enhancing peroxisome proliferator-activated receptor-gamma (PPARγ) activation, followed by inhibition of the PI3K/Akt pathway and intrinsic pathway induction. MH upregulated PPARγ and PTEN expression levels while it decreased p-Akt in the MH-induced apoptotic process, thereby supporting the fact that MH is a PPARγ activator. Additionally, MH decreased the expression of Bcl-2 and Bcl-XL, inducing the intrinsic pathway in MH-treated SiHa cells. Furthermore, MH treatment led to the activation of caspase-3/caspase-9 and proteolytic cleavage of polyADP ribose polymerase. The expression levels of Fas (CD95) and E6/E7 oncogenes were not altered by MH treatment. Taken together, MH activates PPARγ/PTEN expression and induces apoptosis via suppression of the PI3K/Akt pathway and mitochondria-dependent pathways in SiHa cells. These findings suggest that MH has potential for development as a therapeutic agent for human cervical cancer.

• Journal of Microbiology and Biotechnology
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• 제25권3호
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• pp.413-417
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• 2015

Recently, we isolated HY253, a novel decahydrofluorene analog with a molecular structure of 7,8a-divinyl-2,4a,4b,5,6,7,8,8a,9,9a-decahydro-1H-fluorene-2,4a,4b,9a-tetraol from the roots of Aralia continentalis, which is known as Dokwhal (獨活), a traditional medicinal herb. Moreover, we previously reported its cytotoxic activity on cancer cell proliferation in human lung cancer A549 and cervical cancer HeLa cells. The current study aimed to evaluate its detailed molecular mechanisms in cell cycle arrest and apoptotic induction in human hepatocellular carcinoma HepG2 cells. Flow cytometric analysis of HepG2 cells treated with $60{\mu}M$ HY253 revealed appreciable cell cycle arrest at the G1 phase via inhibition of Rb phosphorylation and down-regulation of cyclin D1. Furthermore, using western blots, we found that up-regulation of cyclin-dependent kinase inhibitors, such as p21^CIP1 and p27^KIP1, was associated with this G₁ phase arrest. Moreover, TUNEL assay and immunoblottings revealed apoptotic induction in HepG2 cells treated with $60{\mu}M$ HY253 for 24 h, which is associated with cytochrome c release from mitochondria, via down-regulation of anti-apoptotic Bcl-2 protein, which in turn resulted in activation of caspase-9 and -3, and proteolytic cleavage of poly(ADP-ribose) polymerase (PARP). Accordingly, we suggest that HY253 may be a potent chemotherapeutic hit compound for treating human liver cancer cells via up-regulation and activation of the p53 gene.

• Nutrition Research and Practice
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• 제14권3호
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• pp.203-217
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• 2020

BACKGROUND/OBJECTIVE: Centella asiatica, also known as Gotu kola, is a tropical medicinal plant native to Madagascar, Southeast Asia, and South Africa. It is well known to have biological activities, including wound healing, anti-inflammatory, antidiabetic, cytotoxic, and antioxidant effects. The purpose of this study was to determine the efficacy of extracts of C. asiatica against age-related eye degeneration and to examine their physiological activities. MATERIALS/METHODS: To determine the effects of CA-HE50 (C. asiatica 50% EtOH extract) on retinal pigment cells, we assessed the cytotoxicity of CoCl₂ and oxidized-A2E in ARPE-19 cells and observed the protective effects of CA-HE50 against N-methyl-N-nitrosourea (MNU)-induced retinal damage in C57BL/6 mice. In particular, we measured factors related to apoptosis and anti-oxidation and the protein levels of rhodopsin/opsin. We also measured glucose uptake to characterize glucose metabolism, a major factor in cell protection. RESULTS: Induction of cytotoxicity with CoCl₂ and oxidized-A2E inhibited decreases in the viability of ARPE-19 cells when CA-HE50 was administered, and promoted glucose uptake under normal conditions (P < 0.05). In addition, CA-HE50 inhibited degeneration/apoptosis of the retina in the context of MNU-induced toxicity (P < 0.05). In particular, CA-HE50 at 200 mg/kg inhibited the cleavage of pro-caspase-3 and pro-poly (ADP-ribose)-polymerase and maintained the expressions of nuclear factor erythroid 2-related factor 2 and heme oxygenase-1 similar to normal control levels. Rhodopsin/opsin expression was maintained at a higher level than in normal controls. CONCLUSION: A series of experiments confirmed that CA-HE50 was effective for inhibiting or preventing age-related eye damage/degeneration. Based on these results, we believe it is worthwhile to develop drugs or functional foods related to age-related eye degeneration using CA-HE50.

• Journal of Microbiology and Biotechnology
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• 제22권11호
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• pp.1591-1595
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• 2012

We previously isolated a novel compound, HY251, with the molecular structure of 3-propyl-2-vinyl-1,2,3,3a,3b,6,7,7a,8,8a-decahydrocyclopenta[a]indene-3,3a,7a,8a-tetraol from the roots of Aralia continentalis. The current study was designed to evaluate the detailed molecular mechanisms underlying the apoptotic induction by HY251 in human ovarian cancer PA-1 cells. TUNEL assay and Western blot analyses revealed an appreciable apoptotic induction in PA-1 cells treated with $60{\mu}M$ of HY251 for 24 h. This apoptotic induction was associated with caspase-8-dependent Bid cleavage, which in turn resulted in the formation of pro-apoptotic truncated Bid (tBid), and activation of caspase-9 and -3, as well as the cleavage of poly(ADP-ribose) polymerase (PARP). Moreover, we found that this death event was also associated with the significant up-regulation and activation of the p53 tumor-suppressor protein through phosphorylation at Ser15. Therefore, we suggest that HY251 may be a potent cancer chemotherapeutic candidate for the treatment of ovarian cancer.

• Journal of Microbiology and Biotechnology
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• 제21권5호
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• pp.540-544
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• 2011

The molecular mechanisms of apoptotic induction by benzyldihydroxyoctenone (BDH), a nonsteroidal antiandrogen, isolated from the culture broth of Streptomyces sp., have been previously published in prostate cancer LNCaP cells. Apoptotic induction of BDH-treated LNCaP cells was associated with downregulation of Bcl-xL that caused, in turn, cytochrome c release from mitochondria, and activation of procaspases and specific proteolytic cleavage of poly(ADP-ribose) polymerase (PARP). The purpose of the present study was to investigate the patterns of apoptotic induction by BDH in non-prostate, ovarian cancer PA-1 (androgen-independent and -insensitive) cells and prostate cancer cells with different androgen responsiveness, such as C4-2 (androgen-independent and -sensitive), 22Rv1 (androgen-dependent and -low sensitive), and LNCaP (androgen-dependent and -high sensitive) cells. We found that BDH-treated LNCaP cell proliferation was significantly inhibited in a time-dependent manner and induced apoptosis via downregulation of the androgen receptor (AR) and prostate-specific antigen (PSA), as well as antiapoptotic Bcl-xL protein. However, the levels of BDH-mediated apoptotic induction and growth inhibition in 22Rv1 cells were apparently lower than those of LNCaP cells. In contrast, the induction of apoptosis and antiproliferative effect in BDH-treated non-prostate cancer PA-1 and hormone refractory C4-2 cells were not detectable and marginal, respectively. Therefore, BDH-mediated differential apoptotic induction and growth inhibition in a cell type seem to be obviously dependent on its androgen responsiveness; primarily on androgen-dependency, and then on androgensensitivity.

• Journal of Microbiology and Biotechnology
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• 제20권2호
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• pp.433-437
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• 2010

In the course of screening for novel modulators of cell cycle progression and apoptosis as anticancer drug candidates, we generated an analog of sangivamycin, MCS-C2, which was elucidated as 4-amino-6-bromo-7-cyclopentyl-7H-pyrrolo[2,3-d]pyrimidine-5-carboxamide. In the present study, we evaluated the molecular mechanisms of MCSC2-induced cell cycle arrest and apoptosis in A549 human lung cancer cells. To investigate the effects of MCS-C2 on cell cycle progression in A549 cells, we measured the DNA content of A549 cells treated with $5\;{\mu}M$ MCS-C2 using flow cytometry. The analysis revealed an appreciable $G_2$ phase arrest in treated cells. This event was associated with significant upregulation of p53 and $p21^{Cip1}$. In addition, the TUNEL assay was used to examine apoptotic induction in treated cells, and the effects of MCS-C2 on the expression of apoptosis-associated proteins were examined by Western blot. Apoptotic induction in MCS-C2-treated A549 cells was associated with cytochrome c release from mitochondria, which in turn resulted in the activation of caspase-9 and -3 and the cleavage of poly(ADP-ribose) polymerase (PARP). Based on these results, we conclude that MCS-C2 is a candidate therapeutic agent for the treatment of human lung cancer via upregulation and activation of p53.

• 약학회지
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• 제53권1호
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• pp.6-11
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• 2009

This study investigated the antiproliferative effect of the EtOH extract from Litsea japonica. The extract markedly inhibited the growth of HL-60 cells. When treated with the extract, several apoptosis events like as DNA fragmentation, chromatin condensation and the increase of the population of sub-G1 hypodiploid cells were observed. The extract decreased the Bcl-2 expression, whereas the Bax expression was increased. Caspase-9 and -3 were activated and poly (ADP-ribose) polymerase was cleaved. The results suggest that the antiproliferative effect of L. japonica in HL-60 appears to arise from apoptosis induction via the down-regulation of Bcl-2 and the activation of caspases.

• International Journal of Oral Biology
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• 제45권3호
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• pp.99-106
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• 2020

Ficus carica L. (fig) is one of the first cultivated crops and is as old as humans. This plant has been extensively used as a traditional medicine for treating diseases, such as cough, indigestion, nutritional anemia, and tuberculosis. However, the physiological activity of fig leaves on oral cancer is as yet unknown. In this study, we investigated the anticancer effect of methanol extracts of Ficus carica (MeFC) and the mechanism of cell death in human FaDu hypopharyngeal squamous carcinoma cells. MeFC decreased the viability of oral cancer (FaDu) cells but did not affect the viability of normal (L929) cells, as determined by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide assay and Live and Dead assay. In addition, MeFC induced apoptosis through the proteolytic cleavage of procaspase-3, -9, poly (ADP-ribose) polymerase (PARP), downregulation of Bcl-2, and upregulation of Bax, as determined by 4′,6-diamidino-2-phenylindole dihydrochloride staining and western blot analysis. Moreover, a concentration of MeFC without cytotoxicity (0.25 mg/mL) significantly suppressed colony formation, a hallmark of cancer development, and completely inhibited the colony formation at 1 mg/mL. Collectively, these results suggest that MeFC exhibits a potent anticancer effect by suppressing the growth of oral cancer cells and colony formation via caspase- and mitochondrial-dependent apoptotic pathways in FaDu human hypopharyngeal squamous carcinoma cells. Therefore, the methanol extract of Ficus carcica leaves provide a natural chemotherapeutic drug for human oral cancer.