• Journal of Ginseng Research
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• 제44권4호
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• pp.593-602
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• 2020

Background: Heat stress orchestrates neurodegenerative disorders and results in the formation of reactive oxygen species that leads to cell death. Although the immunomodulatory effects of ginseng are well studied, the mechanism by which ginseng alleviates heat stress in the brain remains elusive. Methods: Rats were exposed to intermittent heat stress for 6 months, and brain samples were examined to elucidate survival and antiinflammatory effect after Korean Red Ginseng (KRG) treatment. Results: Intermittent long-term heat stress (ILTHS) upregulated the expression of cyclooxygenase 2 and inducible nitric oxide synthase, increasing infiltration of inflammatory cells (hematoxylin and eosin staining) and the level of proinflammatory cytokines [tumor necrosis factor α, interferon gamma (IFN-γ), interleukin (IL)-1β, IL-6], leading to cell death (terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay) and elevated markers of oxidative stress damage (myeloperoxidase and malondialdehyde), resulting in the downregulation of antiapoptotic markers (Bcl-2 and Bcl-x_L) and expression of estrogen receptor beta and brain-derived neurotrophic factor, key factors in regulating neuronal cell survival. In contrast, KRG mitigated ILTHS-induced release of proinflammatory mediators, upregulated the mRNA level of the antiinflammatory cytokine IL-10, and increased myeloperoxidase and malondialdehyde levels. In addition, KRG significantly decreased the expression of the proapoptotic marker (Bax), did not affect caspase-3 expression, but increased the expression of antiapoptotic markers (Bcl-2 and Bcl-x_L). Furthermore, KRG significantly activated the expression of both estrogen receptor beta and brain-derived neurotrophic factor. Conclusion: ILTHS induced oxidative stress responses and inflammatory molecules, which can lead to impaired neurogenesis and ultimately neuronal death, whereas, KRG, being the antioxidant, inhibited neuronal damage and increased cell viability.

• Journal of Microbiology and Biotechnology
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• 제4권1호
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• pp.30-35
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• 1994

A varient strain of budding yeast, Hansenula anomala B-7 which had been identified to be highly resistant to cadmium ions, were observed by transmission electron microscopy. It was shown that the cells accumulated excess amounts of cadmium ions throughout inside the cell rather than on the cell surface. The cell growth in response to cadmium or heat shock stress has also been investigated. It was observed that the cells precultured in the presence of 500 $\mu$ g/ml of Cd ions grew slower than those precultured at 1, 000 $\mu$ g/ml of the metal ions, when they were cultivated in the media containing 1, 000 $\mu$g/ml of the metal ions. Heat shock, however, stimulated the cell growth transiently, when the cells were allowed to grow in the presence of 1, 000 $\mu$g/ml of the metal ions. But the cells given heat shock for more than 100 min received permanent damage to growth. Effects of both stresses on budding rate was also examined. It revealed that the stresses did not change the budding ratio much, which was contradictory to that observed from the same budding yeast, Saccharomyces cerevisiae. Furthermore, the cells treated with 1, 000 $\mu$g/ml of the metal ions not only induced, but also switched off the expression of several new proteins. Some of the cadmium stress-inducible proteins were estimated to be also induced by heat shock stress.

• 한국패류학회지
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• 제29권3호
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• pp.181-187
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• 2013

In order to investigate environmental stress inducible genes in abalone, we analyzed differentially expressed transcripts from a Pacific abalone, Haliotis discus hannai, after exposure to heat-, cold- or hyposalinity-shock by suppression subtractive hybridization (SSH) method. 1,074 unique sequences from SSH libraries were composed to 115 clusters and 986 singletons, the overall redundancy of the library was 16.3%. From the BLAST search, of the 1,316 ESTs, 998 ESTs (75.8%) were identified as known genes, but 318 clones (24.2%) did not match to any previously described genes. From the comparison results of ESTs pattern of three SSH cDNA libraries, the most abundant EST was different in each SSH library: small heat shock protein p26 (sHSP26) in heat-shock, trypsinogen 2 in cold-shock, and actin in hyposalinity SSH cDNA library. Based on sequence similarities, several response-to-stress genes such as heat shock proteins (HSPs) were identified commonly from the abalone SSH libraries. HSP70 gene was induced by environmental stress regardless of temperature-shock or salinity-stress, while the increase of sHSP26 mRNA expression was not detected in cold-shock but in heat-shock condition. These results suggest that the suppression subtractive hybridization method is an efficient way to isolate differentially expressed gene from the invertebrate environmental stress-response transcriptome.

• Journal of Microbiology
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• 제38권3호
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• pp.145-149
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• 2000

GroEL is a typical molecular chaperone. GroEL synthesis patterns at various culture temperatures in Escherichia coli were investigated in this study. No significant differences in the amount of GroEL produced from the chromosome were found at 30 and 37$^{\circ}C$. However, GroEL production increased 3.4-fold at 42$^{\circ}C$. GroEL synthesis was not transient but continuous at 42$^{\circ}C$, although most heat shock gene expression is known to be transient. To understand the role of the groEL structural gene, a groE promoter-lacZ fusion was constructed. Interestingly , while transcriptional fusion is not thermally inducible, it is inducible by ethanol, suggesting that the secondary structure of the groEL transcript is involved in thermal regulation of the groEL gene. Secondary structures of groE mRNA at 37 and 42$^{\circ}C$ were compared using the computer program RNAdraw. Distinct structures at the two temperatures were found, and these structures may be related to a high level of GroEL expression at 42$^{\circ}C$.

• The Korean Journal of Physiology and Pharmacology
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• 제18권5호
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• pp.403-409
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• 2014

The Bis protein is known to be involved in a variety of cellular processes including apoptosis, migration, autophagy as well as protein quality control. Bis expression is induced in response to a number of types of stress, such as heat shock or a proteasome inhibitor via the activation of heat shock factor (HSF)1. We report herein that Bis expression is increased at the transcriptional level in HK-2 kidney tubular cells and A172 glioma cells by exposure to oxidative stress such as $H_2O_2$ treatment and oxygen-glucose deprivation, respectively. The pretreatment of HK-2 cells with N-acetyl cysteine, suppressed Bis induction. Furthermore, HSF1 silencing attenuated Bis expression that was induced by $H_2O_2$, accompanied by increase in reactive oxygen species (ROS) accumulation. Using a series of deletion constructs of the bis gene promoter, two putative heat shock elements located in the proximal region of the bis gene promoter were found to be essential for the constitutive expression is as well as the inducible expression of Bis. Taken together, our results indicate that oxidative stress induces Bis expression at the transcriptional levels via activation of HSF1, which might confer an expansion of antioxidant capacity against pro-oxidant milieu. However, the possible role of the other cis-element in the induction of Bis remains to be determined.

• Journal of Microbiology
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• 제34권2호
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• pp.137-143
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• 1996

We isolated a promoter inducible by paraquat, a superoxide-generating agent, from Escherichia coli using a promoter-probing plasmid pRS415. From sequence analysis we found out the promoter is for fpr ENCODING nadph : ferredoxin oxidoreductase. We constructed on operon fusion of lacZ gene with fpr promoter to monitor the expression of the gene in the single-copy state. LacZ expression generators, menadione and plumbagin, also induced the expression of .betha.-galactosidase in the fusion strain. On the other hand, no significant induction was observed by treatment with hydrogen peroxide, ethanol, and heat shock. Induction of .betha.-galactosidase was significantly reduced by introducing a .DELTA. sox 8 :: cat of soxS3 :: Tn10 mutation into the fusion strain, indicating that fpr gene is a member of the soxRS regulon. The transcriptional start site was determined by primer extension analysis. Possible roles of fpr induction in superoxide stress were discussed.

• 한국양식학회지
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• 제20권4호
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• pp.205-211
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• 2007

Stress-inducible proteins may function in part as molecular chaperones, protecting cells from damage due to various stresses and helping to maintain homeostasis. We examined the mRNA expression patterns of a 68-kDa heat shock protein (HSP68) and 78-kDa glucose-regulated protein (GRP78) in relation to physiological changes in Pacific oyster Crassostrea gigas under osmotic stress. Expression of HSP68 and GRP78 mRNA in the gill significantly increased until 48 h in a hypersaline environment (HRE) and 72 h in a hyposaline environment (HOE), and then decreased. Osmolality and the concentrations of $Na^+$, $Cl^-$, and $Ca^{2+}$ in the hemolymph of HRE oysters significantly increased until 72 h (the highest value) and then gradually decreased; in HOE oysters, these values significantly decreased until 72 h (the lowest value), and then increased. These results suggest that osmolality and $Na^+$, $Cl^-$, and $Ca^{2+}$ concentrations were stabilized by HSP68 and GRP78, and indicate that these two stress-induced proteins play an important role in regulating the metabolism and protecting the cells of the Pacific oysters exposed to salinity changes.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• 제36권5호
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• pp.346-352
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• 2010

Introduction: Heat shock protein70 (HSP70) is a highly conserved family of proteins produced after a variety of stresses. Many studies reported that the overexpression of HSP70 can improve the prognosis of the patients with sepsis through a reduction of the nitric oxide concentration. However, these results only revealed the effect of HSP70 and nitric oxide. No studies have examined the relationship between HSP70 and nitric oxide. The aim of this study was to evaluate the effect of the overexpression of HSP70 on the expression of inducible nitric oxide synthase and the nitric oxide concentration. In addition, the mechanism of the relationship of HSP70 and inducible nitric oxide synthase (iNOS) in sepsis was examined. Materials and Methods: The experiments were performed on male sprague-dawley rats. Sepsis was induced by a cecal ligation and puncture (CLP). Glutamine (GLN) or saline was administered 1 hour after the initiation of sepsis. Serum and lung tissues were acquired from the rats 12 hours or 24 hours after the initiation of sepsis. The nitric oxide concentration, the expression of HSP70 in lung, and the gene expression of iNOS in lung were analyzed. The three groups, sham operation, CLP and CLP+GLN, were compared. Results: Compared to the other groups, in CLP+GLN, GLN administered after the initiation of sepsis enhanced the expression of HSP70 in the lung at 12 hours ($47.19{\pm}10.04$ vs. $33.22{\pm}8.28$, P=0.025) and 24 hours ($47.06{\pm}10.60$ vs. $31.90{\pm}4.83$, P=0.004). In CLP+GLN, GLN attenuated the expression of iNOS messenger RNA (mRNA) in the lung at 12 hours ($5,513.73{\pm}1,051.60$ vs. $4,167.17{\pm}951.59$, P=0.025) and 24 hours ($18,740.27{\pm}8,241.20$ vs. $9,437.65{\pm}2,521.07$, P=0.016), and reduced the concentration of nitric oxide in the serum at 12 hours ($0.86{\pm}0.48$ vs. $3.82{\pm}2.53$, P=0.016) and 24 hours ($0.39{\pm}0.25$ vs. $1.85{\pm}1.70$, P=0.025). Conclusion: The overexpression of HSP70 induced by the administration of GLN in sepsis attenuates the expression of the iNOS gene but reduces the nitric oxide concentration.

• The Korean Journal of Physiology and Pharmacology
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• 제22권4호
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• pp.457-465
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• 2018

The expression of BCL-2 interacting cell death suppressor (BIS), an anti-stress or anti-apoptotic protein, has been shown to be regulated at the transcriptional level by heat shock factor 1 (HSF1) upon various stresses. Recently, HSF1 was also shown to bind to BIS, but the significance of these protein-protein interactions on HSF1 activity has not been fully defined. In the present study, we observed that complete depletion of BIS using a CRISPR/Cas9 system in A549 non-small cell lung cancer did not affect the induction of heat shock protein (HSP) 70 and HSP27 mRNAs under various stress conditions such as heat shock, proteotoxic stress, and oxidative stress. The lack of a functional association of BIS with HSF1 activity was also demonstrated by transient downregulation of BIS by siRNA in A549 and U87 glioblastoma cells. Endogenous BIS mRNA levels were significantly suppressed in BIS knockout (KO) A549 cells compared to BIS wild type (WT) A549 cells at the constitutive and inducible levels. The promoter activities of BIS and HSP70 as well as the degradation rate of BIS mRNA were not influenced by depletion of BIS. In addition, the expression levels of the mutant BIS construct, in which 14 bp were deleted as in BIS-KO A549 cells, were not different from those of the WT BIS construct, indicating that mRNA stability was not the mechanism for autoregulation of BIS. Our results suggested that BIS was not required for HSF1 activity, but was required for its own expression, which involved an HSF1-independent pathway.

• BMB Reports
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• 제42권1호
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• pp.16-21
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• 2009

Three novel Class A genes that encode heat shock transcription factor (HSF) were cloned from Oryza Sativa L using a yeast hybrid method. The OsHSF7 gene was found to be rapidly expressed in high levels in response to temperature, which indicates that it may be involved in heat stress reception and response. Over-expression of OsHSF7 in transgenic Arabidopsis could not induced over the expression of most target heat stress-inducible genes of HSFs; however, the transcription of some HSF target genes was more abundant in transgenic plants following two hours of heat stress treatment. In addition, those transgenic plants also had a higher basal thermotolerance, but not acquired thermotolerance. Collectively, the results of this study indicate that OsHSF7 might play an important role in the response to high temperature. Specifically, these findings indicate that OsHSF7 may be useful in the production of transgenic monocots that can over-express protective genes such as HSPs in response to heat stress, which will enable such plants to tolerate high temperatures.