• Journal of Ginseng Research
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• 제47권5호
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• pp.615-621
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• 2023

Korean Red Ginseng (KRG) plays a key role in heme oxygenase (HO)-1 induction under physical and moderate oxidative stress conditions. The transient and mild induction of HO-1 is beneficial for cell protection, mitochondrial function, regeneration, and intercellular communication. However, chronic HO-1 overexpression is detrimental in severely injured regions. Thus, in a chronic pathological state, diminishing HO-1-mediated ferroptosis is beneficial for a therapeutic approach. The molecular mechanisms by which KRG protects various cell types in the central nervous system have not yet been established, especially in terms of HO-1-mediated mitochondrial functions. Therefore, in this review, we discuss the multiple roles of KRG in the regulation of astrocytic HO-1 under pathophysiological conditions. More specifically, we discuss the role of the KRG-mediated astrocytic HO-1 pathway in regulating mitochondrial functions in acute and chronic neurodegenerative diseases as well as physiological conditions.

• BMB Reports
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• 제43권6호
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• pp.432-437
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• 2010

LBH is a transcription factor as a candidate gene for CHD associated with partial trisomy 2p syndrome. To identify potential LBH-interacting partners, a yeast two-hybrid screen using LBH as a bait was performed with a human heart cDNA library. One of the clones identified encodes ${\alpha}B$-crystallin. Co-immunoprecipitation and GST pull-down assays showed that LBH interacts with ${\alpha}B$-crystallin, which is further confirmed by mammalian two-hybrid assays. Co-localization analysis showed that in COS-7 cells, ${\alpha}B$-crystallin that is cytoplasmic alone, accumulates partialy in the nucleus when co-transfected with LBH. Transient transfection assays indicated that overexpression of LBH or ${\alpha}B$-crystallin reduced the transcriptional activities of p53 and p21, respectively, Overexpression of both ${\alpha}B$-crystallin and LBH together resulted in a stronger repression of the transcriptional activities of p21 and p53. These results showed that the interaction of LBH and ${\alpha}B$-crystallin may inhibit synergistically the transcriptional regulation of p53 and p21.

• Journal of Genetic Medicine
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• 제12권1호
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• pp.25-30
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• 2015

Purpose: Charcot-Marie-Tooth disease (CMT) is a peripheral neuropathy mainly divided into CMT type 1 (CMT1) and CMT2 according to the phenotype and genotype. Although molecular pathologies for each genetic causative have not been revealed in CMT2, the correlation between cell death and accumulation of misfolded proteins in the endoplasmic reticulum (ER) of Schwann cells is well documented in CMT1. Establishment of in vitro models of ER stress-mediated Schwann cell death might be useful in developing drug-screening systems for the treatment of CMT1. Materials and Methods: To develop high-throughput screening (HTS) systems for CMT1, we generated cell models using transient expression of mutant proteins and chemical induction. Results: Overexpression of wild type and mutant peripheral myelin protein 22 (PMP22) induced ER stress. Similar results were obtained from mutant myelin protein zero (MPZ) proteins. Protein localization revealed that expressed mutant PMP22 and MPZ proteins accumulated in the ER of Schwann cells. Overexpression of wild type and L16P mutant PMP22 also reduced cell viability, implying protein accumulation-mediated ER stress causes cell death. To develop more stable screening systems, we mimicked the ER stress-mediated cell death in Schwann cells using ER stress inducing chemicals. Thapsigargin treatment caused cell death via ER stress in a dose dependent manner, which was measured by expression of ER stress markers. Conclusion: We have developed genetically and chemically induced ER stress models using Schwann cells. Application of these models to HTS systems might facilitate the elucidation of molecular pathology and development of therapeutic options for CMT1.

• Molecules and Cells
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• 제26권5호
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• pp.454-458
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• 2008

Sex steroid hormone receptors play a central role in modulating telomerase activity, especially in cancer cells. However, information on the regulation of steroid hormone receptors and their distinct functions on telomerase activity within the mesenchymal stem cell are largely unavailable due to low telomerase activity in the cell. In this study, the effects of estrogen ($E_2$) treatment and function of estrogen receptor alpha ($ER{\alpha}$) and estrogen receptor beta ($ER{\beta}$) on telomerase activity were investigated in human mesenchymal stem cells (hMSCs). Telomerase activity and mRNA expression of the catalytic subunit of telomerase (hTERT) were upregulated by treatment of the cells with $E_2$. The protein concentration of $ER{\alpha}$ was also increased by $E_2$ treatment, and enhancement of $ER{\alpha}$ accumulation in the nucleus was clearly detected with immunocytochemistry. When $ER{\alpha}$ expression was reduced by siRNA transfection into hMSCs, the effect of $E_2$ on the induction of hTERT expression and telomerase activity was diminished. In contrast, the transient overexpression of $ER{\alpha}$ increased the effect of $E_2$ on the expression of hTERT mRNA. These findings indicate that the activation of hTERT expression and telomerase activity by $E_2$ in hMSCs depends on $ER{\alpha}$, but not on $ER{\beta}$.

• BMB Reports
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• 제45권11호
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• pp.647-652
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• 2012

We previously reported that MSTO-211H cells have a higher capacity to regulate Nrf2 activation in response to changes in the cellular redox environment. To further characterize its biological significance, the response of Nrf2, a transcription factor that regulates ARE-containing genes, on the synergistic cytotoxic effect of clofarabine and resveratrol was investigated in mesothelioma cells. The combination treatment showed a marked growth-inhibitory effect, which was accompanied by suppression of Nrf2 activation and decreased expression of heme oxygenase-1 (HO-1). While transient overexpression of Nrf2 conferred protection against the cytotoxicity caused by their combination, knockdown of Nrf2 expression using siRNA enhanced their cytotoxic effect. Pretreatment with Ly294002, a PI3K inhibitor, augmented the decrease in HO-1 level by their combination, whereas no obvious changes were observed in Nrf2 levels. Altogether, these results suggest that the synergistic cytotoxic effect of clofarabine and resveratrol was mediated, at least in part, through suppression of Nrf2 signaling.

• 동의생리병리학회지
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• 제28권2호
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• pp.162-168
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• 2014

Fruits of Schisandra chinensis (SC) Baill are considered a traditional herbal medicine for the treatment and alleviation of various diseases. The purpose of this study was to investigate the anti-cancer effects of SC extract in human breast adenocarcinoma cells (MCF-7). We used human breast adenocarcinoma cell line, MCF-7 cells. We examined cell death by MTT assay and caspase 3 and 9 assay with SC extract. To examine the inhibitory effects of SC extract, cell cycle (sub G1) analysis and mitochondrial membrane depolarization was done the MCF-7 cells after one day with SC extract. In addition, to investigate the transient receptor potential melastatin 7 (TRPM7) currents, we used the whole cell patch clamp techniques. Furthermore, TRPM7 channels were overexpressed in human embryonic kidney (HEK) 293 cells to identify the role of TRPM7 channels in MCF-7 cell growth and survival. SC extract inhibited the growth of MCF-7 cells in a dose-dependent fashion. Also we showed that SC extract induced apoptosis in MCF-7 cells by MTT assay, caspase 3 and 9 assay, sub-G1 analysis and mitochondrial membrane depolarization. SC extract inhibited the TRPM7 currents in MCF-7 cells and in TRPM7 overexpressed HEK 293 cells. Furthermore, TRPM7 channel overexpression in HEK 293 cells exacerbated SC extract-induced cell death. Our findings provide insight into unraveling the effects of SC extract in human breast adenocarcinoma cells and developing therapeutic agents against breast cancer.

• Molecules and Cells
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• 제39권6호
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• pp.477-483
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• 2016

Heat shock factors (Hsfs) are central regulators of abiotic stress responses, especially heat stress responses, in plants. In the current study, we characterized the activity of the Hsf gene HsfA3 in Arabidopsis under oxidative stress conditions. HsfA3 transcription in seedlings was induced by reactive oxygen species (ROS), exogenous hydrogen peroxide ($H_2O_2$), and an endogenous $H_2O_2$ propagator, 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). HsfA3-overexpressing transgenic plants exhibited increased oxidative stress tolerance compared to untransformed wild-type plants (WT), as revealed by changes in fresh weight, chlorophyll fluorescence, and ion leakage under light conditions. The expression of several genes encoding galactinol synthase (GolS), a key enzyme in the biosynthesis of raffinose family oligosaccharides (RFOs), which function as antioxidants in plant cells, was induced in HsfA3 overexpressors. In addition, galactinol levels were higher in HsfA3 overexpressors than in WT under unstressed conditions. In transient transactivation assays using Arabidopsis leaf protoplasts, HsfA3 activated the transcription of a reporter gene driven by the GolS1 or GolS2 promoter. Electrophoretic mobility shift assays showed that GolS1 and GolS2 are directly regulated by HsfA3. Taken together, these findings provide evidence that GolS1 and GolS2 are directly regulated by HsfA3 and that GolS enzymes play an important role in improving oxidative stress tolerance by increasing galactinol biosynthesis in Arabidopsis.

• Molecules and Cells
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• 제45권6호
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• pp.413-424
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• 2022

Suppressor of mothers against decapentaplegic homolog (SMAD) 4 is a pluripotent signaling mediator that regulates myriad cellular functions, including cell growth, cell division, angiogenesis, apoptosis, cell invasion, and metastasis, through transforming growth factor β (TGF-β)-dependent and -independent pathways. SMAD4 is a critical modulator in signal transduction and functions primarily as a transcription factor or cofactor. Apart from being a DNA-binding factor, the additional SMAD4 mechanisms in tumor suppression remain elusive. We previously identified methyl malonyl aciduria cobalamin deficiency B type (MMAB) as a critical SMAD4 binding protein using a proto array analysis. This study confirmed the interaction between SMAD4 and MMAB using bimolecular fluorescence complementation (BiFC) assay, proximity ligation assay (PLA), and conventional immunoprecipitation. We found that transient SMAD4 overexpression down-regulates MMAB expression via a proteasome-dependent pathway. SMAD4-MMAB interaction was independent of TGF-β signaling. Finally, we determined the effect of MMAB downregulation on cancer cells. siRNA-mediated knockdown of MMAB affected cancer cell metabolism in HeLa cells by decreasing ATP production and glucose consumption as well as inducing apoptosis. These findings suggest that SMAD4 controls cancer cell metabolism by regulating MMAB.

• Journal of Nutrition and Health
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• 제49권6호
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• pp.429-436
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• 2016

본 연구에서는 피부의 표피와 진피에 분포하는 HaCaT 세포와 HDF 세포를 이용하여 항산화효과가 우수한 두릅순 추출물의 처리가 UVB에 의한 피부광노화를 억제할 수 있는지 알아보기 위하여 피부 염증반응과 관련한 사이토카인과 피부의 주요 구성 단백질인 collagen에 영향을 미칠 수 있는 MMP-1, type-I procollagen, TRPV-1 등의 단백질 발현에 미치는 영향을 분석하였다. HaCaT에 두릅순 추출물을 24시간 전처리한 경우 UVB ($55 mJ/cm^2$) 노출로 인해 증가한 염증매개인자인 IL-6, IL-8, $PGE_2$를 유의하게 감소시켰다. 또한, 피부 collagen의 정상적인 구조 및 양에 영향을 미치는 단백질들의 발현을 측정한 결과 HaCaT에서는 UVB 조사로 인해 증가한 TRPV-1과 MMP-1 단백질의 발현이 두릅순 에탄올 추출물의 전처리로 모두 감소하였고, HDF에서는 UVB를 조사한 대조군에 비하여 두릅순 추출물 처리가 MMP-1 단백질 발현을 감소시키는 동시에 collagen의 전구체인 type-I procollagen의 발현을 증가시키는 효과를 보였다. 이들 결과들로부터 항산화효과가 우수한 두릅순 70% 에탄올 추출물은 피부세포에서 UVB에 의한 염증반응을 억제시키는 동시에 피부 collagen의 감소를 억제시킴으로써 피부 광노화를 예방할 수 있는 천연 소재로 이용될 수 있다고 본다.

• 한국치위생학회지
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• 제24권3호
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• pp.219-227
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• 2024

연구목적: 치수는 신경과 혈관을 포함하고 있는 부위로 다양한 자극이나 세균에 의해 염증이 생기면 이를 치수염이라고 한다. 치수염은 말초 신경조직 변화와 심한 통증을 유발하는 질환으로 만성적 통증을 유발하나, 삼차신경절의 신경세포 활성화와 특정 나트륨 채널(Nav1.7) 발현 사이의 관계는 잘 알려져 있지 않다. 이에 본 연구에서는 실험적으로 유도된 치수염이 말초신경에서 Nav1.7 나트륨 채널의 발현을 활성화시켜, 삼차신경절의 뉴런을 활성화함으로써 통증을 유발한다는 사실을 발견하고 이를 조절하는 신호기전을 규명하고자 하였다. 연구방법: 실험동물(Male C57BL/6 생쥐, 6주, 20-25 g)의 상악 제1대구치 치수에 AITC를 처리하여 급성 치수염을 유발하고, 3일 후 실시간 광영상 이미지를 이용하여 삼차신경절의 뉴런 활성화를 측정 및 비교 분석하였다. 단백질 분석을 통해 뇌간(SpVc)에서 치수염 통증유발 신호조절기전에 관여하는 여러가지 단백질들(p-ERK, c-FOS, TRPA1, p-CRMP2)의 발현을 관찰하였다. 연구결과: 시공간적 광영상 이미지를 통해 삼차신경절의 뉴런세포들은 대조군과 비교 시 급성 치수염 모델에서 흥분성 활성화가 유도되어 신경학적 변화가 일어남을 관찰하였다. 또한 조직학 및 분자생물학적 결과를 통해 치수염으로 인한 특정 나트륨 채널(Nav1.7)의 증가가 통증을 유발한다는 사실을 확인하였다. 또한, ProTxII(Nav1.7의 선택적 억제 약물) 처리를 통해 뉴런의 과흥분성 활성이 억제됨에 따라, 치수염이 삼차신경절에서 나트륨 채널(Nav1.7)의 증가를 유도하고 이러한 특정 나트륨 채널을 효과적으로 제어하면 치수염의 통증을 줄이는 방법이 될 것이라 생각된다. 결론: 본 연구의 결과를 통해 과 발현된 특정 나트륨 채널(Nav1.7)을 억제하면 삼차신경절에서 통각 신호 처리를 조절하고 치수염에 의해 유발되는 통증을 효과적으로 조절할 수 있음을 시사한다.