• 식품저장과 가공산업
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• 제7권1호
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• pp.9-18
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• 2008

The health benefits of garlic (Allium sativum L.) are derived from a wide variety of components and from the different ways it is administered. The known health benefits of garlic include cardiovascular protective effects, stimulation of immune function, reduction of blood glucose level, protection against microbial, viral and fungal infections, as well as anticancer effects. In the present study, it was examined the effects of water extract of A. sativum (WEAS) on the growth of cultured human tumor cells in order to investigate its anti-proliferative mechanism. Treatment of WEAS to tumor cells resulted in the growth inhibition, especially in leukemia cells, which was associated with induction of G2/M arrest of the cell cycle and apoptosis. In order to further explore the critical events leading to apoptosis in WEAS-treated U937 human leukemia cells, the following effects of WEAS on components of the mitochondrial apoptotic pathway were examined: generation of reactive oxygen species (ROS), alteration of the mitochondrial membrane potential (MMP), and the expression changes of Bcl-2 and IAP family proteins. The cytotoxic effect of WEAS was mediated by its induction of apoptosis as characterized by the occurrence of DNA ladders, apoptotic bodies and chromosome condensation in U937 cells. The WEAS-induced apoptosis in U937 cells was correlated with the generation of intracellular ROS, collapse of MMP, activation of caspase-3 and down-regulation of anti-apoptotic proteins. The quenching of ROS generation with antioxidant N-acetyl-L-cysteine conferred significant protection against WEAS-elicited ROS generation, caspase-3 activation, G2/M arrest and apoptosis. In conclusion, the present study reveals that the cellular ROS generation plays a pivotal role in the initiation of WEAS-triggered apoptotic death in U937 cells.

• Journal of Acupuncture Research
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• 제21권2호
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• pp.41-55
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• 2004

Objective : To investigate the possible molecular mechanism (s) of melittin as a candidate of anti-cancer drug, we examined the effects of the compound on the growth of human lung carcinoma cell line A549. Methods : Growth inhibitory study, flow cytometry analysis, SDS-polyacrylamide gel electrophoresis and Western blot analysis, RT-PCR and in vitro caspases activity assay were performed. Results : Melittin treatment declined the cell viability of A549 cells in a concentration-dependent manner, which was associated with induction of apoptotic cell death. Melittin treatment down-regulated the levels of Bcl-XS/L mRNA and protein expression of A549 cells, an anti-apoptotic gene, however, the those of Bax, a pro-apoptotic gene, were up-regulated. Melittin induced the proteolytic cleavage and activation of caspase-3 and caspase-9 protease in a dose-dependent manner without alteration of inhibitor of apoptosis proteins family and Akt expression. Western blot analysis and RT-PCR data revealed that the levels of tumor suppressor p53 and cyclin-dependent kinase inhibitor p21 were also remained unchanged. Conclusions : Taken together, these findings suggest that melittin-induced inhibition of human lung cancer cell growth is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products, and melittin may have therapeutic potential in human lung cancer.

• Biomolecules & Therapeutics
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• 제22권3호
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• pp.184-192
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• 2014

${\beta}$-lapachone is a naturally occurring quinone that selectively induces apoptotic cell death in a variety of human cancer cells in vitro and in vivo; however, its mechanism of action needs to be further elaborated. In this study, we investigated the effects of ${\beta}$-lapachone on the induction of apoptosis in human gastric carcinoma AGS cells. ${\beta}$-lapachone significantly inhibited cellular proliferation, and some typical apoptotic characteristics such as chromatin condensation and an increase in the population of sub-G1 hypodiploid cells were observed in ${\beta}$-lapachone-treated AGS cells. Treatment with ${\beta}$-lapachone caused mitochondrial transmembrane potential dissipation, stimulated the mitochondria-mediated intrinsic apoptotic pathway, as indicated by caspase-9 activation, cytochrome c release, Bcl-2 downregulation and Bax upregulation, as well as death receptor-mediated extrinsic apoptotic pathway, as indicated by activation of caspase-8 and truncation of Bid. This process was accompanied by activation of caspase-3 and concomitant with cleavage of poly(ADP-ribose) polymerase. The general caspase inhibitor, z-VAD-fmk, significantly abolished ${\beta}$-lapachone-induced cell death and inhibited growth. Further analysis demonstrated that the induction of apoptosis by ${\beta}$-lapachone was accompanied by inactivation of the phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway. The PI3K inhibitor LY29004 significantly increased ${\beta}$-lapachone-induced apoptosis and growth inhibition. Taken together, these findings indicate that the apoptotic activity of ${\beta}$-lapachone is probably regulated by a caspase-dependent cascade through activation of both intrinsic and extrinsic signaling pathways, and that inhibition of the PI3K/Akt signaling may contribute to ${\beta}$-lapachone-mediated AGS cell growth inhibition and apoptosis induction.

• 한국식품영양과학회지
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• 제40권5호
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• pp.649-659
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• 2011

연구에서는 콩다닥냉이 추출물의 항암활성을 조사하기 위하여 잎 및 뿌리의 열수 추출물(WELVL 및 WELVR)이 HCT116 대장암세포의 증식 억제와 연관된 apoptosis 유도 기전에 관한 연구를 시도하였다. 본 연구의 결과에 의하면 HCT116 세포에 WELVL 및 WELVR을 처리하였을 경우에 유발되는 증식 억제 및 형태 변화는 apoptosis 유발과 밀접한 연관이 있었으며, 증식억제 및 apoptosis 유도 효과는 WELVL에 비하여 WELVR에서 높게 나타났다. 특히 WELVR에 의한 apoptosis 유발에는 FasL의 발현 증가를 통한 caspase-8의 활성화와 이로 인한 Bid 단백질의 단편화와 함께 Bcl-2 family의 발현 변화를 통한 mitochondria의 기능 이상과 이로 인한 caspase-9 및 -3의 활성화, 그리고 기질단백질들의 분해가 중요한 역할을 하는 것으로 나타났다. 또한 IAP family의 발현 감소로 인한 caspase의 활성 증가도 어느 정도 관여하는 것으로 생각되어진다. 따라서 WELVR 처리에 의하여 유발되는 apoptosis는 extrinsic pathway 및 intrinsic pathway를 모두 경유하는 multiple apoptotic pathway에 의하여 조절되는 것으로 생각되며, 이러한 결과들은 인체 암세포에서 콩다닥냉이의 항암작용을 이해하는데 중요한 자료가 될 것이고 나아가 콩다닥냉이 추출물을 포함한 그와 유사한 항암제 후보물질들의 연구 기초자료로서 사용될 수 있을 것으로 생각된다.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2019년도 춘계학술대회
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• pp.111-111
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• 2019

Glycyrrhizae radix is one of the most frequently prescribed ingredients in Oriental medicine, and G. radix extract has been shown to exert anti-cancer effects. However, the cellular and molecular mechanisms of apoptosis by G. radix are poorly defined. In the present study, it was examined the biochemical mechanisms of apoptosis by water extract of G. radix (WEGR) in human bladder T24 cancer cells. It was found that WEGR could inhibit the cell growth of T24 cells in a dose-dependent manner, which was associated with the induction of apoptotic cell death, as evidenced by the formation of apoptotic bodies, DNA fragmentation and increased populations of annexin-V positive cells. The induction of apoptotic cell death by WEGR was connected with an up-regulation of pro-apoptotic Bax protein expression and down-regulation of anti-apoptotic Bcl-2 and Bcl-xL proteins, and inhibition of apoptosis family proteins (XIAP, cIAP-1 and cIAP-2). In addition, apoptosis-inducing concentrations of WEGR induced the activation of caspase-9, an initiator caspase of the mitochondrial-mediated intrinsic pathway, and caspase-3, accompanied by proteolytic degradation of poly (ADP-ribose)-polymerase. WEGR also induced apoptosis via a death receptor-mediated extrinsic pathway by caspase-8 activation, resulting in the down-regulation of total Bid and suggesting the existence of cross-talk between the extrinsic and intrinsic pathways. Taken together, the present results suggest that WEGR may be a potential chemotherapeutic agent for the control of human bladder cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• 제15권13호
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• pp.5455-5461
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• 2014

Background: Saponins are a major active component for the traditional Chinese medicine, Rubus parvifolius L., which has shown clear antitumor activities. However, the specific effects and mechanisms of saponins of Rubus parvifolius L. (SRP) remain unclear with regard to human chronic myeloid leukemia cells. The aim of this study was to investigate inhibition of proliferation and apoptosis induction effects of SRP in K562 cells and further elucidate its regulatory mechanisms. Materials and Methods: K562 cells were treated with different concentrations of SRP and MTT assays were performed to determine cell viability. Apoptosis induction by SRP was determined with FACS and DAPI staining analysis. Western blotting was used to detect expression of apoptosis and survival related genes. Specific inhibitors were added to confirm roles of STAT3 and AMPK pathways in SRP induction of apoptosis. Results: Our results indicated that SRP exhibited obvious inhibitory effects on the growth of K562 cells, and significantly induced apoptosis. Cleavage of pro-apoptotic proteins was dramatically increased after SRP exposure. SRP treatment also increased the activities of AMPK and JNK pathways, and inhibited the phosphorylation expression level of STAT3 in K562 cells. Inhibition of the AMPK pathway blocked the activation of JNK by SRP, indicating that SRP regulated the expression of JNK dependent oon the AMPK pathway. Furthermore, inhibition of the latter significantly conferred resistance to SRP pro-apoptotic activity, suggesting involvement of the AMPK pathway in induction of apoptosis. Pretreatment with a STAT3 inhibitor also augmented SRP induced growth inhibition and cell apoptosis, further confirming roles of the STAT3 pathway after SRP treatment. Conclusions: Our results demonstrated that SRP induce cell apoptosis through AMPK activation and STAT3 inhibition in K562 cells. This suggests the possibility of further developing SRP as an alternative treatment option, or perhaps using it as adjuvant chemotherapeutic agent for chronic myeloid leukemia therapy.

• Imaging Science in Dentistry
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• 제31권4호
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• pp.227-233
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• 2001

Purpose: The purpose of this study was to investigate the apoptosis induction in tissues constituting the craniofacial region of growing rat by irradiation. Materials and Methods: The submandibular gland, brain, articular cartilage of condylar head, and calvarium were extracted from 20-day-old rats irradiated 10 Gy. Apoptosis of each tissue was examined by DNA fragmentation and estimated quantitatively using apoptotic index on TUNEL assay. Apoptotic index of each tissue was calculated by the equation for apoptotic cells/total cells × 1,000 on the images of confocal laser scanning microscopy. Apoptotic index was analyzed statistically according to the time lapse after irradiation on the tissues. Results : In the submandibular gland, apoptotic index was significantly increased from 6 hours after irradiation showing the highest value at 12 hours and decreased to the control level at 3 days after irradiation. In the brain, apoptotic index was abruptly reached to the maximum value at 6 hours after irradiation and decreased to the control level at 4 days after irradiation. Articular cartilage and calvarium showed no or little apoptotic signals. The results obtained by the apoptotic index accorded with that of DNA fragmentation. Conclusion : Radiation was closely related with the apoptosis of submandibular gland and brain but, not related with the apoptosis of the articular cartilage of condylar head and calvarium. The changes induced by radiation of the hard tissues would not be explained by apoptosis.

• 생명과학회지
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• 제25권11호
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• pp.1235-1243
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• 2015

황흑산은 동의보감의 복강과 장옹의 처방을 위해 기록된 처방전으로 오랫동안 사용되어 왔으나, 항암 효능에 대한 구체적인 연구는 전혀 이루어진 바 없다. 본 연구에서는 AGS 인체 위암세포를 대상으로 황흑산 처리에 의한 증식억제와 연관된 apoptosis 유발 및 관련 기전 연구를 수행하였다. AGS 위암세포에 황흑산 추출물을 처리함에 처리 농도 의존적으로 증식이 억제되었으며, 이는 apoptosis 유발과 연관성이 있음을 핵의 형태적 변형과 sub-G1기 세포의 축적 등으로 확인하였다. 황흑산 추출물에 의한 apoptosis 유도에는 pro-apoptotic Bax 단백질의 발현 증가와 anti-apoptotic Bcl-2의 발현 감소 및 미토콘드리아에서 세포질로의 cytochrome c 유리와 연관성이 있었으며, 세포 내 활성산소종(reactive oxygen species, ROS)의 축적을 증가시켰다. 또한 황흑산 추출물에 의한 apoptosis 유발은 caspases (caspase-3, -8 및 -9)의 활성을 증가시켰으며, poly (ADP-ribose)-polymerase 단백질의 단편화를 초래하였다. 그러나 ROS scavenger 및 pan-caspases inhibitor는 황흑산 추출물에 의한 apoptosis의 유발을 거의 완벽하게 억제하였으며, 암세포의 증식억제도 차단하였다. 이상의 결과는 황흑산 추출물에 의한 apoptosis가 ROS 생성 및 caspase 활성 의존적으로 일어남을 의미하는 것으로 황흑산의 항암기전 해석을 이해하고 향후 지속적인 연구를 위한 유용한 자료로 사용될 것이다.

• 생명과학회지
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• 제26권9호
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• pp.1015-1021
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• 2016

Pyrimidine 유도체의 일종인 5-fluorouracil (5-FU)은 광범위하게 사용되는 항암제의 일종으로, thymidylate synthase의 활성을 억제시켜 핵산의 합성 및 대사기능 자애 유발 물질이다. 본 연구에서는 Ewing′s 육종 CHP-100 세포에서 5-FU의 증식억제와 연관된 기전 해석으로 시도하였다. 본 연구의 결과에 의하면, 5-FU 처리 시간의 경과에 따른 CHP-100 세포의 증식억제가 세포주기 G1 arrest 유발에 따른 것임을 알 수 있었다. 5-FU에 의한 CHP-100 세포의 G1 arrest는 retinoblastoma protein (pRB)의 탈인산화에 따른 전사인자 E2F-1 및 E2F-4와의 결합 촉진과 연관성이 있었다. 비록 5-FU 처리가 cyclin-dependent kinases의 발현에는 크게 영향을 주지 않았으나, 정상배지에서 배양된 대조군에 비하여 cyclin A 및 B의 발현이 5-FU 처리 시간 의존적으로 억제되었다. 또한 5-FU에 의한 CHP-100 세포의 G1 arrest는 apoptosis 유도와 연관이 있음을 핵 내 염색질의 응축에 따른 apoptotic body의 형성증가, poly (ADP-ribose) polymerase의 단편화 및 annexin V 염색 등을 통하여 확인하였다. 아울러 5-FU는 pro-apoptotic Bax 단백질의 발현 증가 및 anti-apoptotic Bcl-2의 발현 감소를 통한 mitochondrial membrane potential의 소실을 촉진시켰으며, 이로 인하여 미토콘드리아에서 세포질로의 cytochrome c 유리가 증가시켰음을 알 수 있었다. 따라서 본 연구의 결과는 5-FU에 의한 CHP-100 세포의 증식억제와 연관된 G1 arrest 및 apoptosis 유도에는 pRB의 인산화 억제 및 미토콘드리아 기능의 손상이 최소한 관여하고 있음을 의미하는 것이다.

• 대한수의학회지
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• 제41권4호
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• pp.571-578
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• 2001

방사선 피폭선량의 예측을 위한 방사선 민감 지표 모델 개발의 일환으로 apoptotic fragment assay법이 방사선에 피폭된 후 체내 피폭선량을 예측할 수 있는 지표로의 이용 가능성을 평가하기 위하여 코발트-60 감마선과 의료용 싸이크로트론 50MeV($p{\rightarrow}Be^+$) fast neutron 을 0.25Gy에서 1Gy의 선량을 마우스에 각각 전신 조사한 후 소장 음와세포내 apoptotic crypt cell의 수적 변화를 관찰하였다. 저선량 조사군에서 apoptotic crypt cell의 출현 빈도가 1Gy까지 급격하게 증가한 것으로 보아 방사선이 stem cell 지역에 있는 crypt cell의 형태학적 변화를 유발하는 것으로 나타났다. 이상의 결과는 아포토시스가 손상된 세포를 제거하므로 손상된 방사선 민감 표적 장기의 항상성 유지에 중요한 역할을 하는 것으로 판단되었다. Apoptotic fragments의 발생빈도에 대한 선량-반응 곡선에 있어서 음와세포는 중성자조사군이 $y=0.18+(9.728{\pm}0.887)D+(-4.727{\pm}1.033)D^2$ ($r^2=0.984$)으로, 반면에 감마선조사군은 $y=0.18+(5.125{\pm}0.601)D+(-2.652{\pm}0.7000)D^2$ ($r^2=0.970$)의 식을 얻었다. 이와 같이 중성자조사군과 감마선조사군은 공히 linear quadratic model 로 관찰되었다. apoptotic fragments 의 발생빈도와 조사 선량간에 유의한 효과가 있는 것으로 확인되었다. 이상의 결과에서 조사선량의 증가에 비례하여 방사선 민감 세포의apoptotic fragments 가 수적으로 증가하였으며, 고준위 방사선과 저준위 방사선은 선량 반응 관계식과 시간 경과에 따른 영향이 매우 유사하였으며, 마우스 음와세포의 apoptosis 유도에 대한 중성자선의 방사선 생물학적 효과비(RBE)는 2.072이였다. 그리고 모든 방사선조사군에서 방사선피폭 후 4시간과 6시간에 apoptosis 유도가 가장 많았으며, 음와세포의 형태학적 소견은 정상 대조군에서 관찰되지 않는 전형적인 apoptotic fragments 가 나타났다. 따라서 음와 세포에서의 아포토시스 유도는 방사선 피폭으로 발생된 세포 손상의 생물학적 영향 평가검색, 방사선 방호제의 민감도 검사, 방사성 동위원소의 체내 오염에 대한 체내 피폭선량 예측의 지표 및 방사선 민감 표적장기의 손상정도 파악에 이용 가능할 것임. Apoptotic fragment assay 법은 0.25Gy에서 1Gy 까지의 선량에서 간편하고 빠르며 재현성이 있는 지표로서 방사선 민감 표적 장기의 선량 반응 평가와 방사선 피폭후 조기 피폭선량 예측을 위한 방사선 생물학적 선량측정법의 좋은 지표로 사용할 수 있을 것으로 사료됨.