• Molecules and Cells
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• v.46 no.3
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• pp.142-152
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• 2023

Nuclear factor erythroid 2-related factor 2 (Nrf2) mediates the cellular antioxidant response, allowing adaptation and survival under conditions of oxidative, electrophilic and inflammatory stress, and has a role in metabolism, inflammation and immunity. Activation of Nrf2 provides broad and long-lasting cytoprotection, and is often hijacked by cancer cells, allowing their survival under unfavorable conditions. Moreover, Nrf2 activation in established human tumors is associated with resistance to chemo-, radio-, and immunotherapies. In addition to cancer cells, Nrf2 activation can also occur in tumor-associated macrophages (TAMs) and facilitate an anti-inflammatory, immunosuppressive tumor immune microenvironment (TIME). Several cancer cell-derived metabolites, such as itaconate, L-kynurenine, lactic acid and hyaluronic acid, play an important role in modulating the TIME and tumor-TAMs crosstalk, and have been shown to activate Nrf2. The effects of Nrf2 in TIME are context-depended, and involve multiple mechanisms, including suppression of proinflammatory cytokines, increased expression of programmed cell death ligand 1 (PD-L1), macrophage colony-stimulating factor (M-CSF) and kynureninase, accelerated catabolism of cytotoxic labile heme, and facilitating the metabolic adaptation of TAMs. This understanding presents both challenges and opportunities for strategic targeting of Nrf2 in cancer.

• Korean Journal of Medicinal Crop Science
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• v.17 no.2
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• pp.145-150
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• 2009

This study investigated the protective roles and mechanism of magnolol, from the stem bark of Magnolia officinalis against potential neurotoxin 3-hydroxykynurenine (3-HK)-induced neuronal cell death. For the evaluation of protective role of magnolol, we examined cell viability, apoptotic nuclei, change of mitochondrial membrane potential and caspase activity in human neuroblastoma SH-SY5Y cells. It was found that 3-HK induces neuronal cell death in the human neuroblastoma SH-SY5Y cell line. The reduced cell viability produced characteristic features such as cell shrinkages, plasma membrane blebbing, chromatin condensation, and nuclear fragmentation. The cells treated with 3-HK showed an increase in the concentration of reactive oxygen species (ROS) as well as in caspase activity. In addition, both are involved in the 3-HK-induced apoptosis. Magnolol attenuated the cell viability reduction by 3-HK in both a dose- and time-dependent manner. Optical microscopy showed that magnolol inhibited the cell morphological features in the 3-HK-treated cells. Furthermore, the increase in the ROS concentration and the caspase activities by 3-HK were also attenuated by magnolol. These results showed that magnolol has a protective effect on the 3-HK induced cell death by inhibiting ROS production and caspase activity.

• Animal Bioscience
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• v.34 no.5
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• pp.922-930
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• 2021

Objective: Tibetan pigs, predominantly originating from the Tibetan Plateau, have been subjected to long-term natural selection in an extreme environment. To characterize the metabolic adaptations to hypoxic conditions, transcriptomic and proteomic expression patterns in the livers of Tibetan and Yorkshire pigs were compared. Methods: RNA and protein were extracted from liver tissue of Tibetan and Yorkshire pigs (n = 3, each). Differentially expressed genes and proteins were subjected to gene ontology and Kyoto encyclopedia of genes and genomes functional enrichment analyses. Results: In the RNA-Seq and isobaric tags for relative and absolute quantitation analyses, a total of 18,791 genes and 3,390 proteins were detected and compared. Of these, 273 and 257 differentially expressed genes and proteins were identified. Evidence from functional enrichment analysis showed that many genes were involved in metabolic processes. The combined transcriptomic and proteomic analyses revealed that small molecular biosynthesis, metabolic processes, and organic hydroxyl compound metabolic processes were the major processes operating differently in the two breeds. The important genes include retinol dehydrogenase 16, adenine phosphoribosyltransferase, prenylcysteine oxidase 1, sorbin and SH3 domain containing 2, ENSSSCG00000036224, perilipin 2, ladinin 1, kynurenine aminotransferase 1, and dimethylarginine dimethylaminohydrolase 1. Conclusion: The findings of this study provide novel insight into the high-altitude metabolic adaptation of Tibetan pigs.

• Journal of Life Science
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• v.30 no.8
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• pp.701-707
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• 2020

Gene editing technology using the clustered regularly interspaced short palindromic repeat (CRISPR) and the CRISPR associated protein (Cas)9 has been highly anticipated in developing breeding techniques. In this study, we discuss gene scissors as a tool for silkworm molecular breeding through analysis of Bombyx mori Kynurenine 3-Monooxygenase (BmKMO) gene editing using the CRISPR/Cas9 system and analysis of generational transmission through mutagenesis and selective crossing. The nucleotide sequence of the BmKMO gene was analyzed, and three guide RNAs (gRNAs) were prepared. Each synthesized gRNA was combined with Cas9 protein and then analyzed by T7 endonuclease I after introduction into the BM-N silkworm cell line. To edit the silkworm gene, K1P gRNA and Cas9 complexes were subsequently microinjected into the silkworm embryos; the hatching rate was 18% and the incidence of mutation was 60%. The gene mutation was verified in the heterozygous G0 generation, but no phenotypic change was observed. In homozygotes generated by self-crossing, a mutant phenotype was observed. These results suggest that silkworm molecular breeding using the CRISPR/Cas9 system is possible and could be an effective way of shortening the time required.

• Tuberculosis and Respiratory Diseases
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• v.66 no.4
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• pp.274-279
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• 2009

Background: Uteroglobin (UG) is a secretary protein that has strong immunomodulatory properties, and which is synthesized in most epithelia including lung tissue. Overexpression of UG is associated with decreased expression of cyclooxygenase (COX)-2 and suppression of cancer cell growth. Indoleamine 2,3-dioxygenase (IDO) catalyzes tryptophan along the kynurenine pathway, and both the reduction in local tryptophan and the production of tryptophan metabolites contribute to the immunosuppressive effects of IDO. Methods: In this study, we investigated the pattern of expression of COX-2 and IDO, and the effect of UG transduction in the expression of COX-2 and IDO in several non-small cell lung cancer cell lines, especially A549. Results: Both COX-2 and IDO were constitutionally expressed in A549 and H460 cells, and was reduced by UG transduction. In A549 cells, the slightly increased expression of COX-2 and IDO with the instillation of interferon-gamma (IFN-$\gamma$) was reduced by UG transduction. However, the reduced expression of COX-2 and IDO by UG transduction was not increased with IFN-$\gamma$ instillation in A549 cells. In both the A549 COX-2 sense and the A549 COX-2 anti-sense small interfering RNA (siRNA)-transfected cells, IDO was expressed; expression was reduced by UG transduction, irrespective of the expression of COX-2. Conclusion: The results suggest that the anti-proliferative function of UG may be associated with the immune tolerance pathway of IDO, which is independent of the COX-2 pathway.

• BMB Reports
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• v.53 no.11
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• pp.582-587
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• 2020

It is well known that oxidative stress participates in neuronal cell death caused production of reactive oxygen species (ROS). The increased ROS is a major contributor to the development of ischemic injury. Indoleamine 2,3-dioxygenase 1 (IDO-1) is involved in the kynurenine pathway in tryptophan metabolism and plays a role as an anti-oxidant. However, whether IDO-1 would inhibit hippocampal cell death is poorly known. Therefore, we explored the effects of cell permeable Tat-IDO-1 protein against oxidative stress-induced HT-22 cells and in a cerebral ischemia/reperfusion injury model. Transduced Tat-IDO-1 reduced cell death, ROS production, and DNA fragmentation and inhibited mitogen-activated protein kinases (MAPKs) activation in H₂O₂ exposed HT-22 cells. In the cerebral ischemia/reperfusion injury model, Tat-IDO-1 transduced into the brain and passing by means of the blood-brain barrier (BBB) significantly prevented hippocampal neuronal cell death. These results suggest that Tat-IDO-1 may present an alternative strategy to improve from the ischemic injury.