• Tuberculosis and Respiratory Diseases
• /
• 제60권4호
• /
• pp.451-463
• /
• 2006

연구배경: 활성산소종은 기계환기로 인한 폐손상 (ventilator-induced lung injury, VILI)에서 주요한 역할을 한다. Poly (ADP-ribose) polymerase-1 (PARP1)은 DNA 손상 감시 기능을 하는 단백질로서, DNA 파열을 신호하고 복구에 관여한다. 그러나 활성산소종에 의한 것과 같은 심한 유전자 손상을 받게 되면, 과활성화되어 ${\beta}$-nicotinamide adenine dinucleotide ($NAD^+$)의 결핍을 통한 세포의 사멸을 초래하여, 염증 반응을 일으킨다. 본 연구에서는 VILI의 기전에 있어서 PARP1의 역할 및 그 억제제의 효과를 고찰하고자 하였다. 방법: 48마리의 수컷 C57BL/6 생쥐를 겉보기 수술군 (Sham군), 폐보호적 환기군(lung protective ventilation group, LPV군), 기계환기기로 인한 폐손상군 (ventilator-induced lung injury group, VILI군) 및 PARP1 억제제인 PJ34 전처치 후 기계환기로 인한 폐손상군 (PJ34+VILI군)으로 나누어 실험하였다. LPV군에 대한 기계환기는 $PIP\;15cmH_2O$ + $PEEP\;3cmH_2O$ + RR 90/min. 조건으로, VILI 및 PJ34+VILI군에 대해서는 $PIP\;40cmH_2O$ + $PEEP\;0cmH_2O$ + RR 90/min.의 조건으로 2시간 동안 시행하였다. PJ34+VILI군에서 PARP1 억제제로는, PJ34 20 mg/Kg을 기계환기 2시간 전에 복강 내로 주사하였다. VILI의 정도는 습건중량비 및 급성폐손상 지수로 측정하였고, PARP1의 활성은 biotinylated NAD를 이용한 면역조직화학적 방법을 이용하였다. 또한 기관지폐포세척액 (bronchoalveolar lavage fluid, BALF) 내에서 myeloperoxidase (MPO) 활성 및 tumor necrosis factor-${\alpha}$ ($TNF-{\alpha}$), interleukin-$1{\beta}$ ($IL-1{\beta}$), IL-6 등의 염증성 시토카인의 농도를 측정하였다. 결과: PJ34+VILI군에서 VILI군과 비교하여, PJ34 전처치로 인하여 폐손상의 정도가 현저히 감소하였다 (p<0.05). 5개의 고배율 시야에서 관찰한 PARP1의 활성을 보이는 세포의 수는 VILI군에서 유의하게 증가하였고, PJ34+VILI군에서 현저히 감소하였다 (p=0.001). BALF 내에서 측정한 MPO 활성 및 $TNF-{\alpha}$, $IL-1{\beta}$, IL-6의 농도 역시 PJ34+VILI군에서 의미 있게 감소하였다 (p<0.05). 결론: VILI의 기전에 있어서 PARP1의 과활성이 주요한 역할을 하고, PARP1 억제제가 MPO 활성 및 염증성 시토카인의 감소와 함께 VILI의 발생을 억제한다.

• 대한의생명과학회지
• /
• 제11권4호
• /
• pp.441-446
• /
• 2005

The molecular mechanism of ischemia/reperfusion injury remains unclear. Reactive oxygen species (ROS) are implicated in cell death caused by ischemia/reperfusion in vivo or hypoxia in vitro. Poly (ADP-ribose) polymerase (PARP) activation has been reported to be involved in hydrogen peroxide-induced cell death in renal epithelial cells. This study was therefore undertaken to evaluate the role of P ARP activation in chemical hypoxia in opossum kidney (OK) cells. Chemical hypoxia was induced by incubating cells with antimycin A, an inhibitor of mitochondrial electron transport. Exposure of OK cells to chemical hypoxia resulted in a time-dependent cell death. In OK cells subjected to chemical hypoxia, the generation of ROS was increased, and this increase was prevented by the $H_2O_2$ scavenger catalase. Chemical hypoxia increased P ARP activity and chemical hypoxia-induced cell death was prevented by the inhibitor of PARP activation 3-aminobenzamide. Catalase prevented OK cell death induced by chemical hypoxia. $H_2O_2$ caused PARP activation and $H_2O_2-induced$ cell death was prevented by 3-aminobenzamide. Taken together, these results indicate that chemical hypoxia-induced cell injury is mediated by PARP activation through H202 generation in renal epithelial cells.

• 한국지능시스템학회:학술대회논문집
• /
• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
• /
• pp.166-169
• /
• 2003

Reinforcement learning if a kind of machine learning. It aims to adapt an agent to a given environment with a clue to a reward and a penalty. Q-learning [8] that is a representative reinforcement learning system treats a reward and a penalty at the same time. There is a problem how to decide an appropriate reward and penalty values. We know the Penalty Avoiding Rational Policy Making algorithm (PARP) [4] and the Penalty Avoiding Profit Sharing (PAPS) [2] as reinforcement learning systems to treat a reward and a penalty independently. though PAPS is a descendant algorithm of PARP, both PARP and PAPS tend to learn a local optimal policy. To overcome it, ion this paper, we propose the Multi Best method (MB) that is PAPS with the multi-start method[5]. MB selects the best policy in several policies that are learned by PAPS agents. By applying PS, PAPS and MB to a soccer game environment based on the SoccerBots[9], we show that MB is the best solution for the soccer game environment.

• 대한한방부인과학회지
• /
• 제23권3호
• /
• pp.38-55
• /
• 2010

Purpose: This study was designed to find out the anti-cancer effects of Samultang-Gami which was composed of Rehmanniae Radix(RR), Angelicae Gigantis Radix(AGR), Cnidii Rhizoma(CR), Paeoniae Radix(PR), Cortex Moutan Radicis(CMR), Hedyotis Diffusa(HD) and Caesalpinia Sappan on HeLa, HepG2 and AGS cells. Methods: Various cancer cell lines including HeLa, HepG2 and AGS cells, were used. In vitro anti-cancer effects were measured by MTT assay using cancer cell lines treated with various concentrations of 70% ethanol extract of Samultang-Gami. Expression of cell cycle arrest mediators including Bax, Bcl-2, p53 and DARP-1 proteins were measured by Western blot analysis. Results: 1. Samultang-Gami decreased the viability of HeLa and HepG cells in a dosedependent manner. 2. AGR, CMR, PR and HD decreased the viability of HeLa, HepG2 and AGS cells. 3. We could observe that the decreased Bax and Bcl-2 expression level and the increased PARP-1 expression level by Samultang-Gami extracts treated in HeLa cells. 4. We could observe that the decreased Bcl-2 expression level and the increased Bax, p53 and PARP-1 expression level by RR extracts treated in HeLa cells. and also could observe that the reduction of the protein level of Bcl-2, p53 and PARP-1 and the increase of the protein level of Bax by PR in HeLa cells. 5. We could observe that the increased p53 expression level, the decreased PARP-1's that and the unchanged Bax and Bcl-2's that by Samultang-Gami extracts treated in HepG2 cells. 6. We could observe that the reduced Bcl-2 expression level by each of RR extracts and PR extracts in HepG2 cells. 7. The treatment of Samultang-Gami in AGS cells didn't have any effect on the expression level of Bax, Bcl-2, p53 and PARP-1. 8. We could observe that the increased p53 and PARP-1 expression level by each of CR, RR and PR extracts in AGS cells. Conclusion: Taken together, we suggest that Samultang-Gami exhibits cytotoxic effects on HeLa, HepG2 and AGS cells, causing apoptosis. The results showed that Samultang-Gami may do so by regulating the expression of specific target molecules that promote efficient apoptotic cell death in a dose-dependent manner.

• 대한한방내과학회지
• /
• 제35권1호
• /
• pp.79-91
• /
• 2014

Objectives : To investigate the anti-cancer effect of Palbohoichoon-tang (PBHCT) extracts. Methods : The cell viability was assessed by 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide (MMT) assay and cell morphological changes were microscopically analyzed after staining with $10{\mu}M$ 2-[4-amidinophenyl]-6-indolecarbamidine dihydrochloride (DAPI) and TUNEL. We also analyzed expression of Bcl2, $Bcl_{xL}$, Bax, procaspase-3, procaspase-9, and procyclic acidic repetitive protein (PARP) by western blot method. Results : Observations showed that PBHCT induced the apoptotic cell death proved by increased sub-G1 phase cell population, apoptotic body formation and chromatin condensation. Western blot analysis of total cell lysates revealed that the PBHCT induced cleavage of caspase-9, caspase-3 and poly (ADP-ribose) polymerase (PARP). In addition, PBHCT dose-dependently increased the activity of caspase-9, caspase-3 and PARP-1. Furthermore, PBHCT reduced anti-apoptotic Bcl2, $Bcl_{xL}$ expression which contributed to the loss of mitochondrial membrane potential and the activations of caspase-9 and caspase-3. Conclusions : These findings suggest that PBHCT exerts anti-cancer effects on human neuroblastoma SH-SY5Y cells by inducing apoptotic death via down-regulation of anti-apoptotic proteins such as Bcl2 and $Bcl_{xL}$, up-regulation of pro-apoptotic proteins such as Bax, and activation of caspase cascades and PARP-1.

• 대한의생명과학회지
• /
• 제29권4호
• /
• pp.321-329
• /
• 2023

Anaplastic thyroid cancer has the highest mortality rate of all thyroid cancers and shows low responsiveness to most treatments. Hongyoung, a reddish-colored potato, is an excellent source of dietary polyphenol containing a large amount of anthocyanins, which has anti-cancer and anti-inflammatory effects. This study investigated the effects of Hongyoung extract on apoptosis and invasiveness in SNU-80 anaplastic thyroid cancer cells. The quantification of the total polyphenol content was done by spectrophotometric measurement. Cell growth was measured by using 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl) 2H tetrazolium, monosodium salt (MTS) assay. Cell cycle was analyzed through FACS analysis. Induction of apoptosis in cells was investigated by annexin V staining using flow cytometer and the expression of caspase-3 and Poly (ADP-ribose) polymerase (PARP) through western blot. mRNA expression and protein activation of matrix metalloproteinases (MMP)-2/-9 were examined by RT-PCR and zymography. As a result, the TPC of Hongyoung was 292.43±8.42 mg gallic acid equivalent (GAE)/100 g dry extract. Hongyoung showed a dose-dependent cell growth inhibition, and the IC₅₀ values was 1,000 ㎍/mL. sub-G1 phase was more than doubled compared to the control group, and S and G2/M phase arrest were also induced. Hongyoung induced apoptosis by increasing FITC-Annexin V-positive cells and increased the activation of caspase-3 (cleaved caspase-3) and PARP (fragmented PARP). Hongyoung significantly inhibited mRNA expression and protein activation of MMP-2/-9 in phorbol 12-myristate 13-acetate (PMA)-treated SNU-80 cells. Therefore, this study suggests the possibility of development of Hongyoung extract as an anti-cancer agent.

• Journal of Nutrition and Health
• /
• 제36권8호
• /
• pp.828-833
• /
• 2003

Dially disulfide (DADS), a component of garlic (Allium sativum), has been known to exert potent chemopreventive activity against various cancers. In this study, the synergistic effect of DADS and daunorubicin on the cytotoxicity of HL-60 cells, a human leukemia cell line, was investigated. DADS at 25 M greatly potentiated daunorubicin-induced cell death, decreasing cell viabilityto50%ofthe control. Daunorubicin-induced apoptosis was accompanied by the activation of caspase-3, the degradation of poly-(ADP-ribose) polymerase (PARP) and D4-GDI, and DNA fragmentation, which were blocked by pre-treatment with acetyl-Asp-Glu-Val-Asp- dialdehyde (Ac-DEVD-CHO). Treatment that combined 25 M DADS and 100 nM daunorubicin caused a similar degree of caspase-3 activation, PARP and D4-GDI degradation, and DNA fragmentation to that caused by treatment with 250 nM daunorubicin alone. These results indicate that combined therapy using daunorubicin with DADS, a component of food, and garlic can effectively decrease the therapeutic dose of daunorubicin, preventing the severe side effects of daunorubicin.

• 동의생리병리학회지
• /
• 제19권6호
• /
• pp.1552-1556
• /
• 2005

Silymarin has been known to exert anti-tumoral activity in Korea. However, its molecular mechanism of action is not understood. In this study, we found that silymarin induced apoptosis in androgen-independent prostate cancer DU145 cells as confirmed by DNA fragmentation. Our data demonstrated that silymarin-induced apoptotic cell death was accompanied by activation of caspase-3 and subsequent cleavages of its substrates, poly(ADP-ribose) polymerase (PARP) in a time- and concentration-dependent manner. Also, silymarin-induced apoptotic mechanism of DU145 cells involved the induction of Par-4 protein expression. Taken together, these results suggest that silymarin induces the activation of caspase-3, degradation of PARP, increase of Par-4 expression, and eventually leads to apoptotic cell death.

• 대한본초학회지
• /
• 제36권1호
• /
• pp.1-8
• /
• 2021

Objective : Citri Unshius Pericarpium (Citrus unshiu peel) has been used in Korean medicine to treat indigestion, vomiting, coughing and phlegm. This study investigated the hepatoprotective effect of ethanol extract of Citrus unshiu peel (CEE) in cadmium (CdCl2)-treated mouse model. Methods : CEE was dissolved in water and administered orally to mice once a day for 7 consecutive days. The mice were then exposed to a single intraperitoneal (i.p.) injection of cadmium (4 mg/kg body weight) to induce acute hepatotoxicity. At the end of the experiment, blood and liver tissue samples were collected, analyzed for alanine aminotransferase (ALT), aspartate aminotransferase (AST), and histopathological evaluation. Liver damage was assessed as the percentage of degenerative areas of the hepatic parenchyma, the number of degenerative hepatocytes, and the number of infiltrated inflammatory cells. Results : In cadmium-treated rats, pretreatment with CEE significantly reduced the serum ALT and AST levels associated with liver damage. Histopathologically, CEE prevented degenerative changes on the hepatic tissues including confluent necrosis, congestions and infiltration of inflammatory cells. CEE also reduced the elevation of oxidative stress markers (nitrotyrosine and 4-hydroxynonenal) and apoptosis markers (cleaved caspase-3 and cleaved PARP) positive cells. PARP protein expression in liver tissue was also restored by CEE. Conclusion : This study showed that CEE exerted antioxidant and anti-apoptotic effects against cadmium-induced liver injury. Thus, it can be concluded that CEE can be used to prevent liver damage caused by cadmium.

• 동의생리병리학회지
• /
• 제24권3호
• /
• pp.385-389
• /
• 2010

Butein(3,4,2',4-tetrahydroxychalcone) has been reported anticancer effects in several cancer type, which is prostate, bladder cancer but breast cancer is not. This study was to investigate the antiproliferative effects by butein(3,4,2',4-tetrahydroxychalcone) in MCF-7 human breast carcinoma cells. We invastigated the effects of dose-dependently cell growth inhibition by butein, which could be proved by WST-1 assay. Also, flow cytometry analysis was butein increase percentage of subG1 phase. As well as, butein induces apoptosis through the expression of caspase-8,-3 and poly(ADP-ribose) polymerase(PARP) activation but not in DMSO treated cells. Taken together, this results suggest that butein induced MCF-7 apoptosis through extrinsic pathway and thus may have potential tumor suppressor in breast cancer.