• Proceedings of the Korean Society of Toxicology Conference
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• 2001.10a
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• pp.199-199
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• 2001

Both hypoxia and insulin induce same target genes including vascular endothelial growth factor (VEGF), glycolitic enzymes and glucose transporters. However these two signals eventually trigger quite different metabolic pathways. Hypoxia induces glycolysis for anaerobic ATP production, while insulin increase glycolysis for lipogenesis and energy storage. Hypoxia-induced gene expression is mediated by Hypoxia-inducible Factorl (HIF-1) that consists of HIF-1 $\alpha$ and $\beta$ subunit.(omitted)

• Bulletin of the Korean Chemical Society
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• v.31 no.12
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• pp.3826-3829
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• 2010

• Biomolecules & Therapeutics
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• v.30 no.5
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• pp.465-472
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• 2022

Melanoma is one of the most aggressive skin cancers. Hypoxia contributes to the aggressiveness of melanoma by promoting cancer growth and metastasis. Upregulation of cyclin D1 can promote uncontrolled cell proliferation in melanoma, whereas stimulation of cytotoxic T cell activity can inhibit it. Epithelial mesenchymal transition (EMT) plays a critical role in melanoma metastasis. Hypoxia-inducible factor-1α (HIF-1α) is a main transcriptional mediator that regulates many genes related to hypoxia. CoCl₂ is one of the most commonly used hypoxia-mimetic chemicals in cell culture. In this study, inhibitory effects of IDF-11774, an inhibitor of HIF-1α, on melanoma growth and metastasis were examined using cultured B16F10 mouse melanoma cells and nude mice transplanted with B16F10 melanoma cells in the presence or absence of CoCl₂-induced hypoxia. IDF-11774 reduced HIF-1α upregulation and cell survival, but increased cytotoxicity of cultured melanoma cells under CoCl₂-induced hypoxia. IDF-11774 also reduced tumor size and local invasion of B16F10 melanoma in nude mice along with HIF-1α downregulation. Expression levels of cyclin D1 in melanoma were increased by CoCl₂ but decreased by IDF-11774. Apoptosis of melanoma cells and infiltration of cytotoxic T cells were increased in melanoma after treatment with IDF-11774. EMT was stimulated by CoCl₂, but restored by IDF11774. Overall, IDF-11774 inhibited the growth and metastasis of B16F10 melanoma via HIF-1α downregulation. The growth of B16F10 melanoma was inhibited by cyclin D1 downregulation and cytotoxic T cell stimulation. Metastasis of B16F10 melanoma was inhibited by EMT suppression.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.636-642
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• 2009

The corpus luteum (CL) is a transient endocrine gland that produces progesterone, a product required for the establishment and maintenance of pregnancy. In the absence of pregnancy, the production of progesterone in the CL decreases and the structure itself regresses in size. The life span and function of the CL are regulated by complex interactions between stimulatory (luteotrophic) and inhibitory (luteolytic) mediators. When an ovum is released from a mature follicle, angiogenesis and rapid growth of follicular cells form the CL. The purpose of the present study was to determine whether steroidogenesis, proliferation, and hypoxiarelated proteins are expressed in caprine CL. The expression of proliferating cell nuclear antigen (PCNA), vascular endothelial growth factor (VEGF), and hypoxia-inducible factor $1{\alpha}$ (HIF-$1{\alpha}$) were determined in caprine CL during the estrous cycle. Cytochrome P450 side chain cleavage protein did not vary significantly during the estrous cycle; however, there was an increased expression of $3{\beta}$ -hydroxysteroid dehydrogenase in the early and middle stages, which rapidly decreased in the late stage. The same observations were made with respect to steroidogenic acute regulatory protein. Variations in progesterone content and expression of PCNA, HIF-$1{\alpha}$, and VEGF were consistent with this result. Thus, the steroidogenic proteins, PCNA, HIF-$1{\alpha}$, and VEGF in caprine CL are dependent on the stage of the estrous cycle.

• Journal of Veterinary Science
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• v.23 no.2
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• pp.35.1-35.13
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• 2022

Background: The testis has been reported to be a naturally O2-deprived organ, dimethyloxaloylglycine (DMOG) can inhibit hypoxia inducible factor-1alpha (HIF-1α) subject to degradation under normal oxygen condition in cells. Objectives: The objective of this study is to detect the effects of DMOG on the proliferation and differentiation of spermatogonial stem cells (SSCs) in Bama minipigs. Methods: Gradient concentrations of DMOG were added into the culture medium, HIF-1α protein in SSCs was detected by western blot analysis, the relative transcription levels of the SSC-specific genes were analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR). Six days post-induction, the genes related to spermatogenesis were detected by qRT-PCR, and the DNA content was determined by flow cytometry. Results: Results revealed that the levels of HIF-1α protein increased in SSCs with the DMOG treatment in a dose-dependent manner. The relative transcription levels of SSC-specific genes were significantly upregulated (p < 0.05) by activating HIF-1α expression. The induction results showed that DMOG significantly increased (p < 0.05) the spermatogenesis capability of SSCs, and the populations of haploid cells significantly increased (p < 0.05) in DMOG-treated SSCs when compared to those in DMOG-untreated SSCs. Conclusion: We demonstrate that DMOG can promote the spermatogenesis activity of SSCs.

• Molecules and Cells
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• v.43 no.11
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• pp.945-952
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• 2020

Hypoxia induces the expression of several genes through the activation of a master transcription factor, hypoxia-inducible factor (HIF)-1α. This study shows that hypoxia strongly induced the expression of two carboxypeptidases (CP), CPA4 and CPE, in an HIF-1α-dependent manner. The hypoxic induction of CPA4 and CPE gene was accompanied by the recruitment of HIF-1α and upregulation in the active histone modification, H3K4me3, at their promoter regions. The hypoxic responsiveness of CPA4 and CPE genes was observed in human adipocytes, human adipose-derived stem cells, and human primary fibroblasts but not mouse primary adipocyte progenitor cells. CPA4 and CPE have been identified as secreted exopeptidases that degrade and process other secreted proteins and matrix proteins. This finding suggests that hypoxia changes the microenvironment of the obese hypoxic adipose tissue by inducing the expression of not only adipokines but also peptidases such as CPA4 and CPE.

• Korean Journal of Plant Resources
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• v.35 no.3
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• pp.391-398
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• 2022

Ulcerative colitis (UC) is a typical inflammatory colon disorder. Platycodon grandiflorum (PG) is known to exert various beneficial effects including anti-oxidative and anti-bacterial properties and improvements in liver function. However, the improving effect and mechanism of PG on intestinal inflammation are not fully understood. The present research was designed to investigate the effect of PG on the clinical signs of DSS-induced colitis in mice. The ameliorative effects of PG on inflammatory cytokine expression and the activation of hypoxia-inducible-factor (HIF)-1α in DSS-treated colon tissue were also determined. Our results showed that mice treated with DSS displayed the main clinical symptoms of colitis, including weight loss, bloody stools, decrease in colon length and diarrhea and PG treatment significantly improved the clinical features induced by DSS in mice. PG inhibited the increase in the levels of inflammatory cytokines caused by DSS in colon tissues. We also showed that the anti-inflammatory mechanism of PG involved suppressing the activation of HIF-1α in DSS-treated colon tissues. Collectively, the findings of this study indicate the prospect of developing new drugs from PG for UC treatment.

• Journal of Ginseng Research
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• v.45 no.5
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• pp.610-616
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• 2021

Background: Thymic stromal lymphopoietin (TSLP) acts as a master switch for inflammatory responses. Ginsenoside Rg3 (Rg3) which is an active ingredient of Panax ginseng Meyer (Araliaceae) is known to possess various therapeutic effects. However, a modulatory effect of Rg3 on TSLP expression in the inflammatory responses remains poorly understood. Methods: We investigated antiinflammatory effects of Rg3 on an in vitro model using HMC-1 cells stimulated by PMA plus calcium ionophore (PMACI), as well as an in vivo model using PMA-induced mouse ear edema. TSLP and vascular endothelial growth factor (VEGF) levels were detected using enzyme-linked immunosorbent assay or real-time PCR analysis. Murine double minute 2 (MDM2) and hypoxia-inducible factor 1α (HIF1α) expression levels were detected using Western blot analysis. Results: Rg3 treatment restrained the production and mRNA expression levels of TSLP and VEGF in activated HMC-1 cells. Rg3 down-regulated the MDM2 expression level increased by PMACI stimulation. The HIF1α expression level was also reduced by Rg3 in activated HMC-1 cells. In addition, Rg3-administered mice showed the decreased redness and ear thickness in PMA-irritated ear edema. Rg3 inhibited the TSLP and VEGF levels in the serum and ear tissue homogenate. Moreover, the MDM2 and HIF1α expression levels in the ear tissue homogenate were suppressed by Rg3. Conclusion: Taken together, the current study identifies new mechanistic evidence about MDM2/HIF1α pathway in the antiinflammatory effect of Rg3, providing a new effective therapeutic strategy for the treatment of skin inflammatory diseases.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.11
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• pp.4609-4615
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• 2014

Background: To investigate tumor inhibition effects and mechanisms of Angelica sinensis and Sophorae flavescentis ait decoction (ASSF) combined with diamine-dichloroplatinum (DDP). Materials and Methods: Bodyweight, tumor inhibition rate and q value were calculated for single ASSF or ASSF combined with DDP on H22 carcinoma xenograft KM mice. Biochemical methods for serum LDH, AST, ALT, and AKP, ELISA method for serum HIF-$1{\alpha}$, pathological assessemnt of thymus, immunohistochemistry detection of tumor tissue caspase3 and mutant p53 protein, and qRT-PCR detection of bax/ bcl-2 mRNA were applied. Results: Compared with DDP control group, the bodyweight increased in ASSF-DDP group (p<0.01). Tumor inhibition rates for DDP, ASSF, ASSF-DDP were 62.7%. 43.7% and 71.0% respectively, with a q value of 0.90. Compared with other groups, thymus of DDP control group had obvious pathological injury (p<0.01), serum LDH, AST, ALT, AKP increased significantly in DDP control group (p<0.01), while serum HIF-$1{\alpha}$ was increased in the model control group. Compared with this latter, the expression of mutant p53 protein and bcl-2 mRNA were decreased in all treatment groups (p<0.01), but there were no statistical difference between DDP control p and ASSF-DDP groups. The expression of caspase3 protein and bax mRNA was increased in all treatment groups, with statistical differences between the DDP and ASSF-DDP groups (p<0.01). Conclusions: ASSF can inhibit bodyweight decrease caused by DDP, can inhibit tumor growth synergistically with DDP mainly through increasing serum HIF-$1{\alpha}$ and pro-apoptotic molecules such as caspase 3 and bax, rather than through decreasing anti-apoptotic mutant p53 and bcl-2. ASSF can reduce DDP toxicity due to decreasing the release of LDH, AST, ALT, AKP into blood and enhancing thymus protection.

• Journal of Ginseng Research
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• v.46 no.3
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• pp.408-417
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• 2022

Background: Korean Red Ginseng extract (KRGE) has been used as a health supplement and herbal medicine. Astrocytes are one of the key cells in the central nervous system (CNS) and have bioenergetic potential as they stimulate mitochondrial biogenesis. They play a critical role in connecting the brain vasculature and nerves in the CNS. Methods: Brain samples from KRGE-administered mice were tested using immunohistochemistry. Treatment of human brain astrocytes with KRGE was subjected to assays such as proliferation, cytotoxicity, Mitotracker, ATP production, and O₂ consumption rate as well as western blotting to demonstrate the expression of proteins related to mitochondria functions. The expression of hypoxia-inducible factor-1α (HIF-1α) was diminished utilizing siRNA transfection. Results: Brain samples from KRGE-administered mice harbored an increased number of GFAP-expressing astrocytes. KRGE triggered the proliferation of astrocytes in vitro. Enhanced mitochondrial biogenesis induced by KRGE was detected using Mitotracker staining, ATP production, and O₂ consumption rate assays. The expression of proteins related to mitochondrial electron transport was increased in KRGE-treated astrocytes. These effects were blocked by HIF-1α knockdown. The factors secreted from KRGE-treated astrocytes were determined, revealing the expression of various cytokines and growth factors, especially those related to angiogenesis and neurogenesis. KRGE-treated astrocyte conditioned media enhanced the differentiation of adult neural stem cells into mature neurons, increasing the migration of endothelial cells, and these effects were reduced in the background of HIF-1α knockdown. Conclusion: Our findings suggest that KRGE exhibits prophylactic potential by stimulating astrocyte mitochondrial biogenesis through HIF-1α, resulting in improved neurovascular function.