• 생약학회지
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• 제36권2호통권141호
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• pp.88-92
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• 2005

Apoptosis plays an important role in autoimmune chronic (Hashimoto's) thyroiditis, a disorder that often results in hypothyroidism. The goal of this study was to induce apoptosis by the combination of inflammatory cytokines, interferon $(IFN)-{\gamma}$ and tumor necrosis factor $(TNF)-{\alpha}$, and to investigate a potential role of medicinal plants in the thyroid follicular cells (FRTL) in vitro. The apoptosis was evaluated by cellular viability, DNA fragmentation, and terminal deoxynucleotidyl transferase-mediated deoxy-UTP nick end labeling (TUNEL) assay. Extract of Gamgung-tang (GGT, Glycyrrhizae Radix, black beans, Angelicae Radix, and Cnidii Rhizoma) $(0.3{\sim}9.0mg/ml)$ was shown to maintain the viability of cells treated with $IFN-{\gamma}(100U/ml)$ and $TNF-{\alpha}$ (0.5 ng/ml). FRTL cells were found to undergo DNA fragmentation with the inflammatory cytokines. The extract of GGT inhibited DNA fragmentation in dose-dependent manner. The cells with TUNEL-positive nuclei were detected with $IFN-{\gamma}$ and $TNF-{\alpha}$ treatment. The number of TUNEL-positive cells decreased with the treatment of extract of GGT. These results indicate that medicinal plants inhibit the occurrence of apoptosis in thyroid follicular cells, therefore, may have therapeutic potential in the treatment of autoimmune chronic thyroiditis.

• 동의생리병리학회지
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• 제19권3호
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• pp.623-627
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• 2005

Abnormal thyroid cell proliferation has a very important role in hypothyroidism. Thyroid stimulating hormone (TSH) stimulates proliferation and maintains differentiated function in thyroid follicular cells. A functioning rat thyroid cell line (FRTL) was used to study the effect of Gamgung-tang (GGT, Glycyrrhizae Radix, black beans, Angelicae Radix and Cnidii Rhizoma) on proliferation and cAMP accumulation of thyrocytes. Proliferation of cell was assessed by DNA synthesis and incorporation of $[^3H]thymidine$ into DNA. The concentration of cAMP was measured simultaneously with growth assessment. Extract of GGT ($0.15{\sim}0.9\;mg/ml$ increased DNA synthesis in a dose-dependent manner. GGT at 0.6 (p<0.05) and 0.9 mg/ml (p<0.01) significantly increased $[^3H]thymidine$ incorporation. A comparable effect was observed with TSH. GGT also enhanced cAMP accumulation. These results indicate that GGT increases the proliferation of thyrocytes and may be considered a promising agent for the treatment of autoimmune thyroid disease.

• 생명과학회지
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• 제8권1호
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• pp.51-59
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• 1998

Ursolic acid(UA)의 apoptosis 유도능을 F9 생쥐 기형암종세포를 대상으로 조사하였다. UA는 피부암화의 억제, tumor의 분화유도, tumor promotion의 억제 등의 항암 효과를 나타내는 pentacyclic triterpene acid로 물질로 알려져 있다. UA를 F9세포에 처리하였을 때 농도비례로 성장억제를 나타냈다. 또한 apoptosis과정에서 관찰되는 전형적인 DNA 분절을 관찰할 수 있었고, 전자현미경을 이용한 세포의 미세구조를 관찰한 결과, 역시 apoptosis과정에서 관찰되는 전형적인 형태인 염색질 응축, 핵의 분절들을 관찰할 수 있어, UA에 의한 항암 효과는 apoptosis에 의한 것임을 시사한다. UA에 의한 apoptosis는 단백질 합성저해제인 cycloheximide에 의해 저해됨을 관찰할 수 있었다. UA를 F4쎄포에 처리한 후 oncogene의 발현양상을 조사한 결과, c-myc과 laminin B1은 apoptosis과정동안 점점 감소하고 c-jun은 증가함을 관찰할 수 있었다. 이상의 결과로서 UA에 의한 F9 세포의 apoptosis에는 새로운 단백질의 합성이 요구되며, c-myc 및 laminin의 발현 감소와 c-jumd의 발현 증가가 관여하고 있음을 시사한다.

• 생약학회지
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• 제34권3호통권134호
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• pp.237-241
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• 2003

본 연구는 참깨 종자로부터 추출, 분리된 세사몰린의 백혈병 HL-60 세포의 생장억제에 미치는 영향을 조사하였다. 세사몰린은 농도와 시간 의존적으로 HL-60 세포의 생합성을 억제하였다. $60{\sim}100\;{\mu}g/ml$ 농도의 세사몰린 범위에서 사포증식이 억제적이었다. $200\;{\mu}g/ml$ 이상의 세사몰린 농도에서 HL-60 세포에 세포파괴성으로 나타났다. 그리고 $60\;{\mu}g/ml$에서 HL-60 세포의 DNA, RNA, 단백질의 합성억제 정도는 35.1%, 6.1% 5.3%였다. 반면에 $200\;{\mu}g/ml$에서의 억제 정도는 각각 86.8%, 81.5%, 96.7%였다. DNA 합성에 대한 세사몰린의 억제효과는 비가역적이었다.

• Biomolecules & Therapeutics
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• 제29권1호
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• pp.90-97
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• 2021

Ultraviolet B (UVB) radiation causes DNA base modifications. One of these changes leads to the generation of 8-oxoguanine (8-oxoG) due to oxidative stress. In human skin, this modification may induce sunburn, inflammation, and aging and may ultimately result in cancer. We investigated whether phloroglucinol (1,3,5-trihydroxybenzene), by enhancing the expression and activity of 8-oxoG DNA glycosylase 1 (Ogg1), had an effect on the capacity of UVB-exposed human HaCaT keratinocytes to repair oxidative DNA damage. Here, the effects of phloroglucinol were investigated using a luciferase activity assay, reverse transcription-polymerase chain reactions, western blot analysis, and a chromatin immunoprecipitation assay. Phloroglucinol restored Ogg1 activity and decreased the formation of 8-oxoG in UVB-exposed cells. Moreover, phloroglucinol increased Ogg1 transcription and protein expression, counteracting the UVB-induced reduction in Ogg1 levels. Phloroglucinol also enhanced the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) as well as Nrf2 binding to an antioxidant response element located in the Ogg1 gene promoter. UVB exposure inhibited the phosphorylation of protein kinase B (PKB or Akt) and extracellular signal-regulated kinase (Erk), two major enzymes involved in cell protection against oxidative stress, regulating the activity of Nrf2. Akt and Erk phosphorylation was restored by phloroglucinol in the UVB-exposed keratinocytes. These results indicated that phloroglucinol attenuated UVB-induced 8-oxoG formation in keratinocytes via an Akt/Erk-dependent, Nrf2/Ogg1-mediated signaling pathway.

• 대한의생명과학회지
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• 제26권4호
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• pp.288-295
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• 2020

Infection of Helicobacter pylori on gastric mucosa is associated with various gastric diseases. According to the WHO, H. pylori causes gastric cancer and has been classified as a class I carcinogen. Riboflavin is an essential vitamin which presents in a wide variety of foods. Previous studies have shown that riboflavin/UVA was effective against the growth inhibition of Staphylococcus aureus, S. epidermidis and multidrug-resistant Pseudomonas aeruginosa and had the potential for antimicrobial properties. Thus, we hypothesized that riboflavin has a potential role in the growth inhibition of H. pylori. To demonstrate inhibitory concentration of riboflavin against H. pylori, we performed agar and broth dilution methods. As a result, we found that riboflavin inhibited the growth of H. pylori. The MIC was 1 mM in agar and broth dilution test. Furthermore, to explain the inhibitory mechanism, we investigated whether riboflavin has an influence on the replication-associated molecules of the bacteria using RT-PCR to detect mRNA expression level in H. pylori. Riboflavin treatment of H. pylori led to down-regulation of polA and dnaB mRNA expression levels in a dose dependent manner. After then, we also confirmed whether riboflavin has cytotoxicity to human cells. We used AGS, a gastric cancer cell line, and treated with riboflavin did not show statistically significant decrease of cell viability. Thus, these results indicate that riboflavin can suppress the replication machinery of H. pylori. Taken together, these findings demonstrate that riboflavin inhibits growth of H. pylori by inhibiting replication of the bacteria.

• Molecules and Cells
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• 제44권2호
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• pp.101-115
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• 2021

The INO80 chromatin remodeling complex has roles in many essential cellular processes, including DNA replication. However, the mechanisms that regulate INO80 in these processes remain largely unknown. We previously reported that the stability of Ino80, the catalytic ATPase subunit of INO80, is regulated by the ubiquitin proteasome system and that BRCA1-associated protein-1 (BAP1), a nuclear deubiquitinase with tumor suppressor activity, stabilizes Ino80 via deubiquitination and promotes replication fork progression. However, the E3 ubiquitin ligase that targets Ino80 for proteasomal degradation was unknown. Here, we identified the C-terminus of Hsp70-interacting protein (CHIP), the E3 ubiquitin ligase that functions in cooperation with Hsp70, as an Ino80-interacting protein. CHIP polyubiquitinates Ino80 in a manner dependent on Hsp70. Contrary to our expectation that CHIP degrades Ino80, CHIP instead stabilizes Ino80 by extending its half-life. The data suggest that CHIP stabilizes Ino80 by inhibiting degradative ubiquitination. We also show that CHIP works together with BAP1 to enhance the stabilization of Ino80, leading to its chromatin binding. Interestingly, both depletion and overexpression of CHIP compromise replication fork progression with little effect on fork stalling, as similarly observed for BAP1 and Ino80, indicating that an optimal cellular level of Ino80 is important for replication fork speed but not for replication stress suppression. This work therefore idenitifes CHIP as an E3 ubiquitin ligase that stabilizes Ino80 via nondegradative ubiquitination and suggests that CHIP and BAP1 act in concert to regulate Ino80 ubiquitination to fine-tune its stability for efficient DNA replication.

• The Korean Journal of Physiology and Pharmacology
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• 제9권4호
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• pp.239-246
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• 2005

In the central nervous system, nitric oxide (NO) is associated with many pathological diseases such as brain ischemia, neurodegeneration and inflammation. The epigallocatechin gallate (EGCG), a major compound of green tea, is recognized as protective substance against neuronal diseases. This study is aimed to investigate the effect of EGCG on NO-induced cell death in PC12 cells. Administration of sodium nitroprusside (SNP), a NO donor, decreased cell viability in a dose- and time-dependent manner and induced genomic DNA fragmentation with cell shrinkage and chromatin condensation. EGCG diminished the decrement of cell viability and the formation of apoptotic morphologenic changes as well as DNA fragmentation by SNP. EGCG played as an antioxidant that attenuated the production of reactive oxygen species (ROS) by SNP. The cells treated with SNP showed downregulation of Bcl-2, but upregulation of Bax. EGCG ameliorated the altered expression of Bcl-2 and Bax by SNP. The release of cytochrome c from mitochondria into cytosol and expression of voltage -dependent anion channel (VDAC)1, a cytochrome c releasing channel in mitochondria, were increased in SNP-treated cells, whereas were attenuated by EGCG. The enhancement of caspase-9, preceding mitochondria-dependent pathway, caspase-8 and death receptor-dependent pathway, as well as caspase-3 activities were suppressed by EGCG. SNP upragulated Fas and Fas-L, which are death receptor assembly, whereas EGCG ameliorated the expression of Fas enhanced by SNP. These results demonstrated that EGCG has a protective effect against SNP-induced apoptosis in PC12 cells, through scavenging ROS and regulating the mitocondria- and death receptor-mediated signal pathway. The present study suggest that EGCG might be a natural neuroprotective substance.

• 한국식품영양과학회지
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• 제39권8호
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• pp.1119-1125
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• 2010

본 연구에서는 resveratrol을 전립선 암 치료제로의 활용 가능성을 조사하기 위하여 primary 인체 전립선 암세포에 대한 resveratrol의 성장억제 효과 및 그 기전에 대하여 조사 하였다. Resveratrol은 RC-58T/h/SA#4 세포에서 농도 및 시간에 의존적으로 세포의 증식을 억제하였으며, $IC_{50}$ 값은 암세포인 RC-58T/h/SA#4, LNCaP, PC-3에서는 각각 245, 320, $340\;{\mu}M$, 전립선 정상세포인 RWPE-1에서는 $982\;{\mu}M$로 나타나 정상세포에서보다는 암세포에서 그 독성이 크게 나타났다. 또한 resveratrol에 의해 유도된 세포 사멸은 핵 응축, sub-G1 함량 증가 및 DNA 분절 현상이 나타나 apoptosis를 유도함을 알 수 있었다. Resveatrol은 caspase-8, -9 및 effector casapse-3 활성을 농도 의존적으로 증가시켰으며, caspase 저해제인 z-VAD-fmk로 caspase의 처리 시 resveratrol에 의한 apoptosis 유도 현상이 유의적으로 감소되어 resveratrol에 의한 RC-58T/h/SA#4 세포의 apoptosis 유도에 caspase가 중요한 역할을 하고 있음을 확인하였다. Resveratrol에 의해 anti-apoptotic 인자인 Bcl-2 및 Bid 단백질의 발현은 감소하였으나, pro-apoptotic 인자인 Bax 단백질 발현은 변화가 없었다. 따라서 본 연구는 resveratrol이 RC-58T/h/SA#4세포에서 caspase 의존형 미토콘드리아 경로에 의해 유도되며, resveratrol은 전립선암 치료제로서 사용 가능성을 시사한다.

• 한국응용곤충학회지
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• 제60권2호
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• pp.255-262
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• 2021

감자뿔나방은 감자에 대한 검역 해충으로 알려져 있다. 본 연구는 전자빔 조사가 감자뿔나방의 발육 및 생식, 그리고 DNA 손상에 미치는 영향을 비교하고 억제선량을 조사하였다. 전자빔을 알(0-12시간 이내), 유충(3령과 5령), 번데기(용화 1일 이내), 그리고 성충(우화 1일 이내)에 선량을 증가시키면서 조사하였다. 전자빔 150 Gy는 알의 부화와 부화된 유충의 용화를 완전히 억제하였다. 조사된 알의 부화율은 19.3%였지만, 성충 우화는 완전히 억제되었다. 3령과 5령 유충에 100 Gy를 조사하였을 때, 성충의 우화와 생식은 완전히 억제되었다. 번데기와 성충에 각각 300 Gy와 400 Gy를 조사하였을 때, F₁세대의 부화율이 억제되었다. 전자빔에 대한 감자뿔나방 성충의 DNA 손상 정도를 alkaline comet assay으로 분석하였으며, 전자빔 조사가 선량 의존적으로 감자뿔나방의 DNA 손상 정도를 증가시켰다. 이러한 결과는 감자뿔나방에 대한 식물 검역 처리법으로 전자빔 150 Gy를 권장할 수 있다. 하지만, 감자뿔나방을 방제하기 위해 전자빔을 현장에 적용하기 위해서는 추가적인 연구가 필요할 것으로 사료된다.