• 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.

• The Korean Journal of Physiology and Pharmacology
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• 제24권3호
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• pp.241-248
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• 2020

Luminespib (AUY922), a heat shock proteins 90 inhibitor, has anti-neoplastic and antitumor effects. However, it is not clear whether AUY922 affects events in vascular diseases. We investigated the effects of AUY922 on the platelet-derived growth factor (PDGF)-BB-stimulated proliferation and migration of vascular smooth muscle cells (VSMC). VSMC viability was detected using the XTT (2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide) reagent. To detect the attenuating effects of AUY922 on PDGF-BB-induced VSMCs migration in vitro, we performed the Boyden chamber and scratch wound healing assays. To identify AUY922-mediated changes in the signaling pathway, the phosphorylation of protein kinase B (Akt) and extracellular signal-regulated kinase (ERK) 1/2 was analyzed by immunoblotting. The inhibitory effects of AUY922 on migration and proliferation ex vivo were tested using an aortic ring assay. AUY922 was not cytotoxic at concentrations up to 5 nM. PDGF-BB-induced VSMC proliferation, migration, and sprout outgrowth were significantly decreased by AUY922 in a dose-dependent manner. AUY922 significantly reduced the PDGF-BB-stimulated phosphorylation of Akt and ERK1/2. Furthermore, PD98059 (a selective ERK1/2 inhibitor) and LY294002 (a selective Akt inhibitor) decreased VSMC migration and proliferation by inhibiting phosphorylation of Akt and ERK1/2. Greater attenuation of PDGF-BB-induced cell viability and migration was observed upon treatment with PD98059 or LY294002 in combination with AUY922. AUY922 showed anti-proliferation and anti-migration effects towards PDGF-BB-induced VSMCs by regulating the phosphorylation of ERK1/2 and Akt. Thus, AUY922 is a candidate for the treatment of atherosclerosis and restenosis.

• The Korean Journal of Physiology and Pharmacology
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• 제12권4호
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• pp.171-176
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• 2008

Heat shock proteins (HSPs) serve as molecular chaperones and play a role in cell protection from damage in response to stress stimuli. The aim of this article is to investigate whether HSP22 affects IL-8 expression in vascular smooth muscle cells (VSMCs), and which cellular factors are involved in the HSP-mediated IL-8 induction in that cell type in terms of mitogen activated protein kinase (MAPK) and transcription element. Exposure of aortic smooth muscle cells (AoSMCs) to HSP22 not only enhanced IL-8 release but also induced IL-8 transcript via promoter activation. HSP22 activated ERK and p38 MAPK in AoSMCs. HSP22-induced IL-8 release was inhibited by U0126, but not by SB202190. A mutation in the IL-8 promoter region at the binding site of NF-${\kappa}$ B, but not AP-1 or C/EBP, impaired promoter activation in response to HSP22. Delivery of I ${\kappa}$ B, but not dominant negative c-Jun, lowered HSP22-induced IL-8 release from AoSMCs. These results suggest that HS P22 induces IL-8 in VSMCs via ERK1/2, and that transcription factor NF-kB may be required for the HSP22-induced IL-8 up-regulation.

• Asian Pacific Journal of Cancer Prevention
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• 제16권18호
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• pp.8227-8233
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• 2016

Background: To investigate polymorphisms in heat shock proteins A1B and A1L (HOM) and associated risk of oesophageal carcinoma in Northeast India. Materials and Methods: The study includes oesophageal cancer (ECA) patients attending general outpatient department (OPD) and endoscopic unit of Gauhati Medical College. Patients were diagnosed based on endoscopic and histopathological findings. Genomic DNA was typed for HSPA1B1267 and HSPA1L2437 SNPs using the polymerase chain reaction with restriction fragment length polymorphisms. Results: A total of 78 cases and 100 age-sex matched healthy controls were included in the study with a male: female ratio of 5:3 and a mean age of $61.4{\pm}8.5years$. Clinico-pathological evaluation showed 84% had squamous cell carcinoma and 16% were adenocarcinoma. Dysphagia grades 4 (43.5%) and 5 (37.1%) were observed by endoscopic and hispathological evaluation. The frequency of genomic variation of A1B from wild type A/A to heterozygous A/G and mutant G/G showed a positive association [chi sq=19.9, p=<0.05] and the allelic frequency also showed a significant correlation [chi sq=10.3, with cases vs. controls, OR=0.32, $p{\leq}0.05$]. The genomic variation of A1L from wild T/T to heterozygous T/C and mutant C/C were found positively associated [chi sq=7.02, p<0.05] with development of ECA. While analyzing the allelic frequency, there was no significant association [chi sq=3.19, OR=0.49, p=0.07]. Among all the risk factors, betel quid [OR=9.79, Chi square=35.0, p<0.05], tobacco [OR=2.95, chi square=10.6, p<0.05], smoking [OR=3.23, chi square=10.1, p<0.05] demonstrated significant differences between consumers vs. non consumers regarding EC development. Alcohol did not show any significant association [OR=1.34, chi square=0.69, p=0.4] independently. Conclusions: It can be concluded that the present study provides marked evidence that polymorphisms of HSP70 A1B and HSP70 A1L genes are associated with the development of ECA in a population in Northeast India, A1B having a stronger influence. Betel quid consumption was found to be a highly significant risk factor, followed by smoking and tobacco chewing. Although alcohol was not a potent risk factor independently, alcohol consumption along with tobacco, smoking and betel nut was found to contribute to development of ECA.

• Tuberculosis and Respiratory Diseases
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• 제52권4호
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• pp.355-366
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• 2002

연구배경: 열 전처치는 조직 내에 열충격단백질의 생성을 유도하며 이러한 열 전처치가 내독소로 유도된 쥐의 급성폐손상을 감소시키고 패혈증에 의한 사망률을 감소시킨다고 알려져 있다. 그러나, 폐손상을 유발하는 원인에 노출된 후 가해진 열처치가 폐손상에 미치는 효과에 대하여는 아직까지 잘 알려져 있지 않다. 따라서 본 연구는 내독소 투여 직후 시행한 열충격이 내독소에 의해 유발된 쥐의 급성폐손상에 미치는 영향과 그에 따른 염증성 및 항염증성 사이토카인에 미치는 영항을 알아보고자 하였다. 방 법: 대조군은 백서의 기관지 내로 생리식염수를 투여하였고 열처치 대조군은 생리식염수 투여 직후 열처치를 시행하였다. 내독소군은 열처치 없이 내독소를 기관지내로 투여하였다. 열 전처치군은 내독소 투여 18시간 전에 열 전처치를 시행하였고, 열 동시처치 군은 내독소 투여 직후 열처치를 시행하였다. 내독소 투여 후 6시간에 기관지폐포세척을 시행하여 기관지폐포세척액 내의 호중구 백분율을 측정하였고 폐를 적출하여 myeloperoxidase(MPO)의 활성도를 측정하였으며 기관지폐포세척액과 혈청에서 LDH(lactic dehydrogenase), 단백질, IL(interleukin)-$1{\beta}$, TNF(tumor necrosis factor)-${\alpha}$ 및 IL-10를 측정하였다. 또한 각군에서 폐 조직 내 HSP72의 표현정도를 관찰하였다. 결 과: 1) 내독소군, 열 전처치군 및 열 동시처치군 모두에서 기관지폐포세척액 내의 호중구 백분율, 폐조직이 MPO, 혈청 및 기관지폐포세척액내의 $IL-1{\beta}$, $TNF-{\alpha}$ 및 IL-10이 대조군에 비해 증가하였다(각 p<0.05). 2) 열 동시처치군은 폐조직의 MPO와 기관지폐포세척액 단백질의 농도가 내독소군과 차이가 없었고 기관지폐포세척액의 LDH가 내독소군에 비해 증가하였다(p<0.05). 3) 열 동시처치군의 혈청 $TNF-{\alpha}$의 농도는 내독소군과 비교 시 증가하였다(p=0.01). 결 론: 내독소 투여 직후 시행한 열충격은 내독소로 유도되는 폐손상을 감소시키지 못하며 염증성 사이토카인의 농도를 증가시켰다.

• Molecules and Cells
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• 제22권2호
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• pp.203-209
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• 2006

TBP (TATA-binding protein)-related factor 2 (TRF2) regulates transcription during a nuber of cellular processes. We previously demonstrated that it is localized in the cytoplasm and is translocated to the nucleus by DNA-damaging agents. However, the cytoplasmic localization of TRF2 is controversial. In this study, we reconfirmed its cytoplasmic localization in various ways and examined its nuclear migration. Stresses such as heat shock, redox agents, heavy metals, and osmotic shock did not affect localization whereas genotoxins such as methyl methanesulfonate (MMS), cisplatin, etoposide, and hydroxyurea caused it to migrate to the nucleus. Adriamycin, mitomycin C and ${\gamma}$-rays had no obvious effect. We determined optimal conditions for the nuclear migration. The proportions of cells with nuclei enriched for TRF2 were 25-60% and 5-10% for stressed cells and control cells, respectively. Nuclear translocation was observed after 1 h, 4 h and 12 h for cisplatin, etoposide and MMS and hydroxyurea, respectively. The association of TRF2 with the chromatin and promoter region of the proliferating cell nuclear antigen (PCNA) gene, a putative target of TRF2, was increased by MMS treatment. Thus TRF2 may be involved in genotoxin-induced transcriptional regulation.

• BMB Reports
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• 제47권5호
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• pp.280-285
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• 2014

Cancer cells undergo uncontrolled proliferation, and aberrant mitochondrial alterations. Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a mitochondrial heat shock protein. TRAP1 mRNA is highly expressed in some cancer cell lines and tumor tissues. However, the effects of its overexpression on mitochondria are unclear. In this study, we assessed mitochondrial changes accompanying TRAP1 overexpression, in a mouse cell line, NIH/3T3. We found that overexpression of TRAP1 leads to a series of mitochondrial aberrations, including increase in basal ROS levels, and decrease in mitochondrial biogenesis, together with a decrease in peroxisome proliferator-activated receptor gamma coactivator-$1{\alpha}$ (PGC-$1{\alpha}$) mRNA levels. We also observed increased extracellular signal-regulated kinase (ERK) phosphorylation, and enhanced proliferation of TRAP1 overexpressing cells. This study suggests that overexpression of TRAP1 might be a critical link between mitochondrial disturbances and carcinogenesis.

• Journal of Yeungnam Medical Science
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• 제34권2호
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• pp.174-181
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• 2017

Ferroptosis is a newly recognized type of cell death that results from iron-dependent lipid peroxidation and is different from other types of cell death, such as apoptosis, necrosis, and autophagic cell death. This type of cell death is characterized by mitochondrial shrinkage with an increased mitochondrial membrane density and outer mitochondrial membrane rupture. Ferroptosis can be induced by a loss of activity of system $X_c{^-}$ and the inhibition of glutathione peroxidase 4, followed by the accumulation of lipid reactive oxygen species (ROS). In addition, inactivation of the mevalonate and transsulfuration pathways is involved in the induction of ferroptosis. Moreover, nicotinamide adenine dinucleotide phosphate oxidase and p53 promote ferroptosis by increasing ROS production, while heat shock protein beta-1 and nuclear factor erythroid 2-related factor 2 inhibit ferroptosis by reducing iron uptake. This article outlines the molecular mechanisms and signaling pathways of ferroptosis regulation, and explains the roles of ferroptosis in human disease.

• International Journal of Oral Biology
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• 제37권3호
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• pp.130-136
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• 2012

The GroEL heat-shock protein from Fusobacterium nucleatum, a periodontopathogen, activates risk factors for atherosclerosis in human microvascular endothelial cells (HMEC-1) and ApoE-/- mice. In this study, we analyzed the signaling pathways by which F. nucleatum GroEL induces the proinflammatory factors in HMEC-1 cells known to be risk factors associated with the development of atherosclerosis and identified the cellular receptor used by GroEL. The MAPK and NF-${\kappa}B$ signaling pathways were found to be activated by GroEL to induce the expression of interleukin-8 (IL-8), monocyte chemoattractant protein 1 (MCP-1), intercellular adhesion molecule 1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), E-selectin, and tissue factor (TF). These effects were inhibited by a TLR4 knockdown. Our results thus indicate that TLR4 is a key receptor that mediates the interaction of F. nucleatum GroEL with HMEC-1 cells and subsequently induces an inflammatory response via the MAPK and NF-${\kappa}B$ pathways.

• 생명과학회지
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• 제21권2호
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• pp.251-256
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• 2011

파이토케미컬의 일종인 EGCG는 녹차의 카테킨 성분으로, 세포 내 신호 경로 조절을 통하여 항산화, 항암효과를 나타내는 것으로 알려져 있다. 본 연구에서는 hypoxia 상태인 B16F10 피부암 세포에서 HIF-$1{\alpha}$를 포함한 AMPK의 신호경로를 통하여 EGCG의 apoptosis 유도 효과를 규명하였다. AMPK는 hypoxia, 영양분 결핍, 운동, heat shock 등, 세포 내 ATP의 결핍에 의해서 활성화되며 암세포의 증식을 억제하고 apoptosis를 유도한다. 세포에서 중요한 에너지 센서로서 작용하는 AMPK가 hypoxia 상태의 암세포 내에서는 HIF-$1{\alpha}$의 전사 활성을 유도하는데, HIF-$1{\alpha}$는 hypoxia 상태에서 산소 결핍에 반응하는 첫 번째 전사 조절인자로서 암세포의 생존을 위한 세포내 산소공급과 혈관신생형성을 조절한다. Hypoxia 상태가 아닌 B16F10 세포에서와 hypoxia 상태에서의 B16F10 세포에서 EGCG에 의한 apoptosis 효과를 관찰하였다. 실험 결과, hypoxia 상태에서 EGCG는 더 강한 apoptosis를 유도하며, 혈관신생형성을 조절할 수 있는 HIF-$1{\alpha}$의 전사 활성을 억제시킨다. 이러한 관찰을 통해 EGCG가 hypoxia 상태의 피부암 세포에서 암의 성장과 신생혈관형성을 저해하는 것으로 보인다. 이와 같은 연구는 향후 식품에 첨가된 파이토케미컬을 이용하여 암을 예방하는 연구에서 있어서, 도움이 될 것으로 여겨진다.