• Natural Product Sciences
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• v.23 no.4
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• pp.227-234
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• 2017

Moringa oleifera Lam (M. oleifera, Moringaceae) is a tree of the Moringaceae family that can reach a height of between 5 and 10 m. The current paper presents cytotoxic effect of M. oleifera fruits and its flavonoids 1 and 2. The viability of HCT116 human colon cancer cells were 38.5% reduced by $150{\mu}g/mL$ of ethanolic extracts in a concentration-dependent manner; in addition, we observed the apoptotic features of cell shrinkage and decreased cell size. Bcl-2 family proteins were regulated as determined by Western blotting analysis, suggesting that M. oleifera fruits and their flavonoids 1 and 2 induced apoptosis through an intrinsic pathway. Based on our findings, 70% ethanolic extracts of M. oleifera fruits and flavonoids 1 and 2 might be useful as cytotoxic agents in colorectal cancer therapy.

• BMB Reports
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• v.39 no.5
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• pp.556-559
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• 2006

The Bcl-2 family of proteins regulates mitochondrial functions during cell death by modulating the efflux of death-promoting proteins such as cytochrome c and endonuclease G. Upon the binding of death ligands to their receptors, caspase-8 cleaves Bid, a BH3-only protein, into tBid that causes the mitochondrial damages resulting in the release of cytochrome c and endonuclease G. Also, another BH3-only protein, hNoxa, has been shown to induce the efflux of cytochrome c from the mitochondria. Whether the efflux proteins from the mitochondria in response to tBid or hNoxa are the same or different, however, has not been addressed. We have demonstrated that endonuclease G activities are not detectable among the proteins released from isolated mitochondria by hNoxa but are detectable in that by tBid. These results suggest that the efflux of proteins from the mitochondria are differentially modulated by tBid and hNoxa.

• Natural Product Sciences
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• v.26 no.3
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• pp.191-199
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• 2020

Fucoidan, a natural component of brown seaweed, has various biological activities such as anti-cancer activity, anti-oxidant, and anti-inflammatory against various cancer cells. However, the fucoidan has been implicated in melanoma cells via apoptosis signaling pathway. Therefore, we investigated apoptosis with fucoidan in A2058 human melanoma cells with dose- and time-dependent manners. In our results, A2058 cells viability decreased at relatively short-time and low-concentration through fucoidan. This effects of fucoidan on A2058 cells appeared to be mediated by the induction of apoptosis, as manifested by morphological changes through DNA-binding dye Hoechst 33342 staining. When a dose of 80 ㎍/mL fucoidan was treated, the cells were observed: crescent or ring-like structure, chromatin condensation, and nuclear fragmentation. With the increase at 100 ㎍/mL fucoidan, the cell membrane is intact throughout the total process, including membrane blebbing and loss of membrane integrity as well as increase of sub-G1 DNA. Furthermore, to understand the exact mechanism of fucoidan-treated in A2058 cells, western blotting was performed to detect apoptosis-related protein expression. In this study, Bcl-2 family proteins can be regulated by fucoidan, suggesting that fucoidan-induced apoptosis is modulated by intrinsic pathway. Therefore, expression of Bcl-2 and Bax may result in altered permeability, activating caspase-3 and caspase-9. And the cleaved form of poly ADP-ribose polymerase was detected in fucoidan-treated A2058 cells. These results suggest that A2058 cells are highly sensitive to growth inhibition by fucoidan via apoptosis, as evidenced by activation of extracellular signal-regulated kinases/p38/Bcl-2 family signaling, as well as alteration in caspase-9 and caspase-3.

• The Korea Journal of Herbology
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• v.28 no.2
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• pp.33-38
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• 2013

Objects : Apoptosis leads to the death of a cell. The mitochondrial pathway of apoptosis, a process regulated by the Bcl-2 family of proteins, plays a key role in various biological processes. The tuber of Liriope platyphylla Wang et TANG (Liliaceae), also known as Liriopis tuber, is famous in Oriental medicine owing to its tonic, antitussive, expectorant and anti-asthmatic properties. The purpose of this study was to observe the effect of the Liriopis tuber on mitochondrial-mediated apoptosis in PC-12 cells. Method : A cytotoxic test on Liriopis Tuber water extract was conducted and another MTT assay was conducted to observe the cytoprotective effect against 4-HNE 25 ${\mu}M$ that causes oxidative stress in PC-12 cells for 24 hours. In addition, in order to observe the expression of Bcl-2 and Bax protein involved with apoptosis, western blot was conducted. Results : The LT water extract had no toxicity for PC-12 cell. In the cytoprotective effect against 4-HNE, both of the group treated with 50 ${\mu}g/m{\ell}$ and 100 ${\mu}g/m{\ell}$ of LT water extract showed a significant increase in comparison with the control group. In Bax protein expression, all the experimental groups treated with LT water extract showed a decrease in comparison with the control group but had no significance. In Bcl-2 protein expression, all the experimental groups treated with LT water extract showed a significant increase in comparison with the control group. Conclusion : These results suggest that LT is effective in reducing apoptosis.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.8-15
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• 2008

Saussurea lappa (SL) has been used to reduce abdominal pain and tenesmus in traditional oriental medicine. SL and major compounds of SL, sesquiterpene lactones, have been suggested to possess various biological effects, including anti-tumor, anti-ulcer, anti-inflammatory, anti-viral and cardiotonic activities. Recently, it has been reported that ethanol extracts from roots of SL have antiproliferative effects on gastric cancer cells. To explore the possibility that SL has chemopreventive effects on prostate cancer, we examined whether the hexane extract of SL (HESL) inhibits the growth of LNCaP human prostate cancer cells. Cells were incubated with various concentrations ($0{\sim}4$ mg/L) of HESL in DMEM/F12 containing 5% charcoal stripped fetal bovine serum. HESL substantially decreased viable cell numbers and induced apoptosis of LNCaP cells in dose-dependent manners. HESL increased the levels of cleaved caspase-8, -9, -7 and -3, and poly (ADP-ribose) polymerase. HESL increased the levels of the pro-apoptotic Bak and truncated-Bid proteins whereas it had no effect on the anti-apoptotic Bcl-2, Bcl-xL, or Mcl-1. The present results indicate that HESL inhibits the growth of human prostate cancer cells by inducing apoptosis, which involves the activation of the caspase cascades.

• Biomolecules & Therapeutics
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• v.27 no.1
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• pp.41-47
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• 2019

The apoptotic effects of shikonin (5,8-dihydroxy-2-[(1R)-1-hydroxy-4-methylpent-3-enyl]naphthalene-1,4-dione) on the human colon cancer cell line SNU-407 were investigated in this study. Shikonin showed dose-dependent cytotoxic activity against SNU-407 cells, with an estimated $IC_{50}$ value of $3{\mu}M$ after 48 h of treatment. Shikonin induced apoptosis, as evidenced by apoptotic body formation, sub-G_1$ phase cells, and DNA fragmentation. Shikonin induced apoptotic cell death by activating mitogen-activated protein kinase family members, and the apoptotic process was mediated by the activation of endoplasmic reticulum (ER) stress, leading to activation of the $PERK/elF2{\alpha}/CHOP$ apoptotic pathway, and mitochondrial $Ca^{2+}$ accumulation. Shikonin increased mitochondrial membrane depolarization and altered the levels of apoptosis-related proteins, with a decrease in B cell lymphoma (Bcl)-2 and an increase in Bcl-2-associated X protein, and subsequently, increased expression of cleaved forms of caspase-9 and -3. Taken together, we suggest that these mechanisms, including MAPK signaling and the ER- and mitochondria-mediated pathways, may underlie shikonin-induced apoptosis related to its anticancer effect.

• Development and Reproduction
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• v.12 no.3
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• pp.297-303
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• 2008

BCL-2 family members are essential protein for the regulation of cell death and survival consisting both antiapoptotic and pro-apoptotic proteins. In the present study, we designed and cloned a new apoptotic molecule MCL-1ES BH3M coding a modified protein of MCL-1L. Compared to MCL-1L protein, MCL-1ES BH3M lacks the PEST motifs known to be involved in MCL-1L protein degradation and has seven mutated residues in BH3 domain critical for dimerization with BCL-2 family members. Overexpression of MCL-1ES BH3M induced death of different cells, and its cell killing effect was not blocked by forced expression of the pro-survival protein MCL-1L. Expression of MCL-1ES BH3M protein led to the activation of caspase 9 and caspase 3, suggesting apoptotic cell death, and confocal fluorescent microscopic analyses showed that MCL-1ES BH3M was partially localized in mitochondria. In conclusion, we reported a new apoptotic molecule and determined its cell death activity in cells.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4475-4482
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• 2014

Background: Cisplatin, a DNA damaging agent, induces apoptosis through increasing DNA fragmentation. However, identification of intrinsic resistance molecules against Cisplatin is vital to estimate the success of therapy. Bag-1 (Bcl-2-associated anthanogene) is one anti-apoptotic protein involved in drug resistance impacting on therapeutic efficiency. Elevated levels of this protein are related with increase cell proliferation rates, motility and also cancer development. For this reason, we aimed to understand the role of Bag-1 expression in Cisplatin-induced apoptosis in HeLa cervix cancer cells. Cisplatin decreased cell viability in time- and dose-dependent manner in wt and Bag-1L+HeLa cells. Although, $10{\mu}M$ Cisplatin treatment induced cell death within 24h by activating caspases in wt cells, Bag-1L stable transfection protected cells against Cisplatin treatment. To assess the potential protective role of Bag-1, we first checked the expression profile of interacting anti-apoptotic partners of Bag-1. We found that forced Bag-1L expression prevented Cisplatin-induced apoptosis through acting on Mcl-1 expression, which was reduced after Cisplatin treatment in wt HeLa cells. This mechanism was also supported by the regulation of heat shock protein (Hsp) family members, Hsp90 and Hsp40, which were involved in the regulation Bag-1 interactome including several anti-apoptotic Bcl-2 family members and c-Raf.

• 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.

• BMB Reports
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• v.40 no.6
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• pp.1058-1068
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• 2007

The post-translational modifications of Ser and Thr residues by O-linked $\beta$-N-acetylglucosamine (O-GlcNAc), i.e., O-GlcNAcylation, is considered a key means of regulating signaling, in a manner analogous to protein phosphorylation. Furthermore, it has been suggested that the increased flux of glucose through the hexosamine biosynthetic pathway (HBP) stimulates O-GlcNAcylation, and that this may be responsible for many of the manifestations of type 2 diabetes mellitus. To determine whether excessive O-GlcNAcylation of target proteins results in pancreatic $\beta$ cell dysfunction, we increased nucleocytoplasmic protein O-GlcNAcylation levels in $\beta$ cells by exposing them to streptozotocin and/or glucosamine. Streptozotocin and glucosamine co-treatment increased O-GlcNAcylated proteomic patterns as assessed by immunoblotting, and these increases in nuclear and cytoplasmic protein O-GlcNAcylations were accompanied by impaired insulin secretion and enhanced apoptosis in pancreatic $\beta$ cells. This observed $\beta$cell dysfunction prompted us to examine Akt and Bcl-2 family member proteins to determine which proteins are O-GlcNAcylated under conditions of high HBP throughput, and how these proteins are associated with $\beta$ cell apoptosis. Eventually, we identified ten new O-GlcNAcylated proteins that were expressed during $\beta$ cell apoptosis, and analyzed the functional implications of these proteins in relation to pancreatic $\beta$ cell dysfunction.