• Molecules and Cells
• /
• 제37권2호
• /
• pp.187-187
• /
• 2014

• 한국자원식물학회:학술대회논문집
• /
• 한국자원식물학회 2021년도 춘계학술대회
• /
• pp.52-52
• /
• 2021

Persicaria amphibia as an England native plant, is a rhizomatous perennial, one of the rather amphibious plants. Its aquatic form contains water-soluble sugars, starch, and protein. P. amphibia have up to 18% tannins in stems and rhizomes. Previous studies have confirmed the anti-inflammatory activity of live bacteria roots, but no studies on bioactivity are known. DNA damage responses (DDRs) pathways are considered a crucial factor affecting the alleviation of cellular damage. The ataxia-telangiectasia mutated and Rad3 related (ATM) and checkpoint kinase 2 (Chk2) pathways are the main pathways of DNA damage response. Also, p53 is a key integrator of cellular response to oxidative DNA damage, contributing repair, or leading transcription including apoptosis. In the present study, we conducted an investigation into the inhibitory effects of P. amphibia on oxidative DNA damage for confirming potential to complementary medicine and therapies. In conclusion, P. amphibia can provide protective effects against double-stranded DNA break (DSB) caused by oxidative DNA damage.

• 생명과학회지
• /
• 제29권6호
• /
• pp.679-687
• /
• 2019

본 연구에서는 인체 폐암 세포인 A549를 사용하여 Litsea populifolia 에탄올 추출물(EELP)의 항산화 및 항암활성과 그 분자적 기전에 관하여 연구하였다. 먼저 EELP의 DPPH 라디칼 소거활성을 측정한 결과, $IC_{50}$가 $11.71{\mu}g/ml$로 유의적인 항산화활성을 보였다. 또한 EELP가 인체폐암세포주인 A549와 정상 폐세포인 IMR90의 세포증식에 미치는 영향을 알아본 결과, 정상세포의 생존율에는 거의 영향을 끼치지 않은 반면, EELP 농도의존적으로 A549 세포의 성장이 저해되었으며, 세포 주기 변화를 분석한 결과 EELP에 의해 A549 세포의 강력한 G1 arrest가 유도되는 것을 확인하였다. EELP에 의해 유도되는 G1 arrest는 세포주기 조절 인자인 Cyclin D1, Cyclin E, Cyclin-dependent kinase인 CDK2와 CDK6의 mRNA 발현 감소와 더불어 단백질 발현 감소와 연관되어 있었다. 또한 EELP 처리에 의한 CDK/Cyclin complex의 발현 저해는 DNA 손상에 의해 활성화되는 CHK2의 활성화 형태인 p-CHK2의 발현 증가에 따른 p53 인산화에 따른 활성화와 CDK 활성화 효소인 CDC25A 탈인산화효소의 인산화에 따른 저해에 의해 나타나는 결과로 사료된다. 이러한 결과들로부터 EELP는 두가지 경로인 p53-의존성과 p53-비의존성(ATM/CHK2/CDC25A/CDK2) 경로를 통해 A549의 G1 arrest를 유도하여 세포 증식을 억제하는 것으로 사료된다. 본 연구결과는 EELP가 폐암에 대한 새로운 항암활성 소재로서 사용될 수 있는 가능성을 시사하며, 또한 EELP의 세포주기 조절에 의한 항암기전을 이해하고 향후 지속적 연구를 하는 데 있어서 귀중한 기초자료로 사용될 수 있을 것이다.

• 생명과학회지
• /
• 제23권9호
• /
• pp.1109-1117
• /
• 2013

본 연구에서는 인체 폐암 세포인 A549를 사용하여 택란 메탄올 추출물의 항암활성과 그 분자적 기전에 관하여 연구하였다. 먼저 택란 추출물이 A549의 세포증식에 미치는 영향을 알아본 결과 처리 농도 및 시간 의존적으로 A549의 성장이 저해되었으며, 세포 주기 변화를 분석한 결과 강력한 G1 arrest가 유도되는 것을 확인하였다. 이러한 택란 추출물에 의한 G1 arrest는 세포주기 조절 단백질인 Cyclin D1, Cyclin E 및 Cyclin-dependent kinase인 CDK2, CDK4, CDK6의 발현 감소와 연관되어 있었다. 또한 택란 추출물에 의한 CDK/Cyclin complex의 발현 저해는 DNA 손상에 의해 활성화되는 CHK2의 활성화 형태인 p-CHK2의 발현 증가에 따른 CDK 활성화 효소인 Cdc25A phosphatase의 발현 억제에 의해 나타나는 결과로 사료된다. 반면 종양억제유전자인 p53 및 CDK 억제제인 p21과 p27의 발현량은 증가되지 않았다. 이러한 결과들로부터 택란 추출물은 DNA damage에 의한 ATM/CHK2/Cdc25A/CDK2 pathway를 통해 A549의 G1 arrest를 유도하여 세포의 증식을 억제할 것으로 판단되며, 이때 택란 추출물에 의해 유도되는 G1 arrest는 p53 비의존적인 경로일 것으로 사료된다. 본 연구결과는 택란이 Cdc25A를 target으로 하는 새로운 항암활성 소재로서 사용될 수 있는 가능성을 시사한다. 또한 본 연구결과는 택란 추출물의 세포주기 조절에 의한 항암기전을 이해하고 향후 지속적 연구를 하는 데 있어서 귀중한 기초자료로 사용될 수 있을 것이다.

• 한국환경농학회지
• /
• 제41권4호
• /
• pp.282-287
• /
• 2022

BACKGROUND: Green algae (Chlorella spp.) has been widely used as a biofertilizer to improve the crop yield and quality. However, available information is not enough to verify the mechanism of green algae's beneficial impact on strawberry. This study was conducted to investigate the effect of Chlorella fusca CHK005 application on the growth and nutrient status of strawberry plant and fruit characteristics. METHODS AND RESULTS: A total of 800 seedlings of strawberry variety 'Kuemsil' were planted. Once a week, C. fusca culture solution (1.0 × 10⁷ cells mL^-1) was applied into soil via irrigation in four different concentrations: no application (control), 1/1000 times (× 0.5), 1/500 times (× 1), and 1/250 times (× 2). Result showed that growth of strawberry plant was enhanced by Chlorella application and the highest impact on fresh weight (FW) and chlorophyll content of the plants were observed in × 2 treatment, followed by × 1, × 0.5, and control treatments. The phosphorus (P) concentration in the plant was significantly higher in × 1 and × 2 treatments compared to control. In case of fruit quality, sugar content (°Brix), hardness, and FW were lowest in control, but these values increased as application levels of Chlorella were higher. Also, P and K contents in the fruits increased with increasing the application levels and significant correlation between P content and oBrix in the fruits was found. CONCLUSION(S): Overall, Chlorella application seemed to improve plant growth and fruit quality by increasing the utilization efficiency of P and K in strawberries.

• Molecular & Cellular Toxicology
• /
• 제2권3호
• /
• pp.159-165
• /
• 2006

To determine the anticancer effect of D-amygdalin (D-mandelinitrole-${\beta}$-D-gentiobioside) in human chronic myeloid leukemia cells K562, we profiled the gene expression between amygdalin treatment and control groups. Through 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay, the cytotoxicity of D-amygdalin was $57.79{\pm}1.83%$ at the concentration of 5 mg/mL for 24 h. We performed cDNA microarray analysis and compared the gene expression profiles between D-amygdalin (5 mg/mL, 24 h) treatment and control groups. Among the genes changed by D-amygdalin, we paid attention to cell cycle-related genes, and particularly cell cycle regulator genes; because arrest of cell cycle processing was ideal tactic in remedy for cancer. In our data, expressions of cyclin-dependent kinase inhibitor 1B (p27, Kip1) (CDKN1B), ataxia telangiectasia mutated (includes complementation groups A, C, and D) (ATM), cyclin-dependent kinase inhibitor 1C (p57, Kip2) (CDKN1C), and CHK1 checkpoint homolog (CHEK1, formally known as CHK1) were increased, while expressions of cyclin-dependent kinase 2 (CDK2), cell division cycle 25A (CDC25A), and cyclin E1 (CCNE1) were decreased. The pattern of these gene expressions were confirmed through RT-PCR. Our results showed that D-amygdalin might control cell cycle regulator genes and arrest S phase of cell cycle in K562 cells as the useful anticancer drug.

• Journal of Nutrition and Health
• /
• 제55권4호
• /
• pp.450-461
• /
• 2022

Purpose: DNA damage and repair responses are induced by metabolic diseases and environmental stress. The balance of DNA repair response and the antioxidant system play a role in modulating the entire body's health. This study uses a high-fat and high-calorie (HFC) drink to examine the new roles of a plant-based multivitamin/mineral supplement with phytonutrients (PMP) for regulating the antioxidant system and cellular DNA repair signaling in the body resulting from metabolic stress. Methods: In a double-blind, randomized, parallel-arm, and placebo-controlled trial, healthy adults received a capsule containing either a PMP supplement (n = 12) or a placebo control (n = 12) for 8 weeks. Fasting blood samples were collected at 0, 1, and 3 hours after consuming a HFC drink (900 kcal). The blood samples were analyzed for the following oxidative stress makers: areas under the curve reactive oxygen species (ROS) levels, plasma malondialdehyde (MDA), erythrocytes MDA, urinary MDA, oxidized low-density lipoprotein, and the glutathione:oxidized glutathione ratio at the time points. We further examined the related protein levels of DNA repair signaling (pCHK1 (Serine 345), p-P53 (Serine 15), and 𝛄H2AX expression) in the plasma of subjects to evaluate the time-dependent effects of a HFC drink. Results: In a previous study, we showed that PMP supplementation for eight weeks reduces the ROS and endogenous DNA damage in human blood plasma. Results of the current study further show that PMP supplementation is significantly correlated with antioxidant defense. Compared to the placebo samples, the blood plasma obtained after PMP supplementation showed enhanced DNA damage response genes such as pCHK1(Serine 345) (a transducer of DNA response) and 𝛄H2AX (a hallmark of DNA damage) during the 8 weeks trial on metabolic challenges. Conclusion: Our results indicate that PMP supplementation for 8 weeks enhances the antioxidant system against oxidative stress and prevents DNA damage signaling in humans.

• Journal of Microbiology and Biotechnology
• /
• 제26권2호
• /
• pp.287-294
• /
• 2016

The effect of kaempferol (3,5,7,4-tetrahydroxyflavone), a flavonoid compound that was identified in barnyard millet (Echinochloa crus-galli var. frumentacea) grains, on G₂-checkpoint and apoptotic pathways was investigated in human acute leukemia Jurkat T cell clones stably transfected with an empty vector (J/Neo) or a Bcl-xL expression vector (J/Bcl-xL). Exposure of J/Neo cells to kaempeferol caused cytotoxicity and activation of the ATM/ATR-Chk1/Chk2 pathway, activating the phosphorylation of p53 (Ser-15), inhibitory phosphorylation of Cdc25C (Ser-216), and inactivation of cyclin-dependent kinase 1 (Cdk1), with resultant G₂-arrest of the cell cycle. Under these conditions, apoptotic events, including upregulation of Bak and PUMA levels, Bak activation, mitochondrial membrane potential (Δψm) loss, activation of caspase-9, -8, and -3, anti-poly (ADP-ribose) polymerase (PARP) cleavage, and accumulation of apoptotic sub-G₁ cells, were induced without accompanying necrosis. However, these apoptotic events, except for upregulation of Bak and PUMA levels, were completely abrogated in J/Bcl-xL cells overexpressing Bcl-xL, suggesting that the G₂-arrest and the Bcl-xL-sensitive mitochondrial apoptotic events were induced, in parallel, as downstream events of the DNA-damage-mediated G₂-checkpoint activation. Together these results demonstrate that kaempferol-mediated antitumor activity toward Jurkat T cells was attributable to G₂-checkpoint activation, which caused not only G₂-arrest of the cell cycle but also activating phosphorylation of p53 (Ser-15) and subsequent induction of mitochondria-dependent apoptotic events, including Bak and PUMA upregulation, Bak activation, Δψm loss, and caspase cascade activation.

• The Korean Journal of Physiology and Pharmacology
• /
• 제26권6호
• /
• pp.439-446
• /
• 2022

The antitumoral effects of valdecoxib (Val), an United States Food and Drug Administration-approved anti-inflammatory drug that was withdrawn due to the side effects of increased risk of cardiovascular adverse events, were investigated in hypopharyngeal squamous cell carcinoma cells by performing a cell viability assay, transwell assay, immunofluorescence imaging, and Western blotting. Val markedly inhibited cell viability with an IC50 of 67.3 µM after 48 h of treatment, and also downregulated cell cycle proteins such as Cdks and their regulatory cyclin units. Cell migration and invasion were severely suppressed by inhibiting integrin α4/FAK expression. In addition, Val activated the cell cycle checkpoint CHK2 in response to excessive DNA damage, which led to the activation of caspase-3/9 and induced caspase-dependent apoptosis. Furthermore, the signaling cascades of the PI3K/AKT/mTOR and mitogen-activated protein kinase pathways were significantly inhibited by Val treatment. Taken together, our results indicate that Val can be used for the treatment of hypopharyngeal squamous cell carcinoma.

• Molecules and Cells
• /
• 제40권8호
• /
• pp.567-576
• /
• 2017

The $Na^+/H^+$ exchanger is responsible for maintaining the acidic tumor microenvironment through its promotion of the reabsorption of extracellular $Na^+$ and the extrusion of intracellular $H^+$. The resultant increase in the extracellular acidity contributes to the chemoresistance of malignant tumors. In this study, the chemosensitizing effects of cariporide, a potent $Na^+/H^+-exchange$ inhibitor, were evaluated in human malignant mesothelioma H-2452 cells preadapted with lactic acid. A higher basal level of phosphorylated (p)-AKT protein was found in the acid-tolerable H-2452AcT cells compared with their parental acid-sensitive H-2452 cells. When introduced in H-2452AcT cells with a concentration that shows only a slight toxicity in H-2452 cells, cariporide exhibited growth-suppressive and apoptosis-promoting activities, as demonstrated by an increase in the cells with pyknotic and fragmented nuclei, annexin V-PE(+) staining, a $sub-G_0/G_1$ peak, and a $G_2/M$ phase-transition delay in the cell cycle. Preceding these changes, a cariporide-induced p-AKT down-regulation, a p53 up-regulation, an ROS accumulation, and the depolarization of the mitochondrial-membrane potential were observed. A pretreatment with the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 markedly augmented the DNA damage caused by the cariporide, as indicated by a much greater extent of comet tails and a tail moment with increased levels of the p-histone H2A.X, $p-ATM^{Ser1981}$, $p-ATR^{Ser428}$, $p-CHK1^{Ser345}$, and $p-CHK2^{Thr68}$, as well as a series of pro-apoptotic events. The data suggest that an inhibition of the PI3K/AKT signaling is necessary to enhance the cytotoxicity toward the acidtolerable H-2452AcT cells, and it underlines the significance of proton-pump targeting as a potential therapeutic strategy to overcome the acidic-microenvironment-associated chemotherapeutic resistance.