• Journal of Microbiology and Biotechnology
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• 제32권5호
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• pp.645-656
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• 2022

Gossypol, a natural phenolic aldehyde present in cotton plants, was originally used as a means of contraception, but is currently being studied for its anti-proliferative and anti-metastatic effects on various cancers. However, the intracellular mechanism of action regarding the effects of gossypol on pancreatic cancer cells remains unclear. Here, we investigated the anti-cancer effects of gossypol on human pancreatic cancer cells (BxPC-3 and MIA PaCa-2). Cell counting kit-8 assays, annexin V/propidium iodide staining assays, and transmission electron microscopy showed that gossypol induced apoptotic cell death and apoptotic body formation in both cell lines. RNA sequencing analysis also showed that gossypol increased the mRNA levels of CCAAT/enhancer-binding protein homologous protein (CHOP) and activating transcription factor 3 (ATF3) in pancreatic cancer cell lines. In addition, gossypol facilitated the cleavage of caspase-3 via protein kinase RNA-like ER kinase (PERK), CHOP, and Bax/Bcl-2 upregulation in both cells, whereas the upregulation of ATF was limited to BxPC-3 cells. Finally, a three-dimensional culture experiment confirmed the successful suppression of cancer cell spheroids via gossypol treatment. Taken together, our data suggest that gossypol may trigger apoptosis in pancreatic cancer cells via the PERK-CHOP signaling pathway. These findings propose a promising therapeutic approach to pancreatic cancer treatment using gossypol.

• 대한의생명과학회지
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• 제14권1호
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• pp.59-62
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• 2008

This experiment was performed to study the effect of TSH (thyroid-stimulating hormone) on the expression of endoplasmic reticulum (ER) chaperones in the rat thyrocytes FRTL-5 cells. Although the expressions of ER membrane kinases (ATF6, IRE1 and PERK) were specially enhanced under absence of TSH, no remarkable up- or down regulations of ER chaperones (BiP, CHOP and Calnexin) were detected by TSH. We firstly report here that TSH by dose up-regulated expression of ER membrane kinases in FRTL-5 culture thyrocytes.

• 대한의생명과학회지
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• 제16권1호
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• pp.65-67
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• 2010

The endoplasmic reticulum (ER) is a multifunctional intercellular organelle in which several posttranslational modification steps occurred such as protein folding, lipid biosynthesis, calcium storage and release. Perturbations that disrupt ER homeostasis lead to the misfolding of proteins in the ER lumen and up-regulation of ER signaling pathway called the unfolded protein response (UPR). Here, we have demonstrated that ageing changes the expression of ER chaperone and associated ER membrane kinases of IRE1, ATF6 and PERK.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.545-548
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• 2002

$(Ba_{0.6-x}Sr_{0.4}Ca_x)TiO_3$(BSCT) (x=0.10, 0.15, 0.20) powders were prepared by the sol-gel method and BSCT thick films were fabricated by the screen-printing method. The structural properties as a faction of the composition ratio were studied. As a result of the differential thermal analysis (DTA), exothermic perk was observed at around $860^{\circ}C$ dne to the formation of the polycrystalline perovskite phase. The BSCT thick films sintered at $1350^{\circ}C$ for 2h showed the average grain size of $2{\sim}7{\mu}m$. The average thickness of BSCT thick films, obtained by 3 times of screen-printing, was approximately $85{\mu}m$.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 하계종합학술대회 논문집 I
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• pp.242-245
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• 2003

This paper introduces a new algorithm of pulse generation and detection for UWB communication system. The existing UWB systems using Gaussian pulse have some difficulties to cope with bandwidth limitation and frequency transition. Moreover. the system sensitivity to channel noise has made the processes of acquisition and tacking difficult. in this paper, we introduce a new pulse generation method which is able to control the bandwidth and center frequency applying modulation method. thus could improve the detection performance of receiving algorithm. Also, we made a system to search maximum perk by applying the proposed algorithm and consequently could guarantee the correct detection. By the result of simulation, when accumulate 10 times at every 2dB band shifting from 0 to 18dB on AWGN channel, we could confirm the proposed method has 97.4% PDR(Pulse Detection Rate) and 1.868% FAR(False Alarm Rate) performance at 4dB SNR and 15% transmission power threshold level.

• 한국축산식품학회:학술대회논문집
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• 한국축산식품학회 2006년도 정기총회 및 제37차 춘계 국제학술발표대회
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• pp.219-223
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• 2006

In the current study, the addition of either NaCl or GdL Increased the binding strength and it considered that the use of GdL with or without low NaCl concentration improved the binding strength of restructured pork meat. Major deterioration of GdL addition is cooked-like discoloration. However, the combination with washing process or addition of carrageenan could improve cold-set binding properties of restructured pork, even if low NaCl or GdL were added.

• Molecules and Cells
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• 제41권8호
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• pp.705-716
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• 2018

The endoplasmic reticulum (ER) is a critical organelle for protein synthesis, folding and modification, and lipid synthesis and calcium storage. Dysregulation of ER functions leads to the accumulation of misfolded- or unfolded-protein in the ER lumen, and this triggers the unfolded protein response (UPR), which restores ER homeostasis. The UPR is characterized by three distinct downstream signaling pathways that promote cell survival or apoptosis depending on the stressor, the intensity and duration of ER stress, and the cell type. Mammalian cells express the UPR transducers IRE1, PERK, and ATF6, which control transcriptional and translational responses to ER stress. Direct links between ER stress and immune responses are also evident, but the mechanisms by which UPR signaling cascades are coordinated with immunity remain unclear. This review discusses recent investigations of the roles of ER stress in immune responses that lead to differentiation, maturation, and cytokine expression in immune cells. Further understanding of how ER stress contributes to the pathogenesis of immune disorders will facilitate the development of novel therapies that target UPR pathways.

• 생명과학회지
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• 제25권4호
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• pp.473-480
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• 2015

진핵세포의 소포체는 분비를 담당하는 첫 번째 기관이다. 대부분의 분비단백질과 막 형성단백질은 소포체에서 세포질/핵으로 전달되는 신호전달에 의한 번역후수식에 의해서 소포체를 통해서 분비된다. 그 결과 완전하게 접 힘이 일어난 단백질만 세포 밖으로 분비된다. 소포체내에서 완전하게 접힘이 일어나지 않아 축적된 단백질은 세 포내스트레스(소포체스트레스)가 되어 unfolded protein response (UPR)시스템을 작동시킨다. UPR을 작동시키는 3종류의 소포체막단백질은 inositol requiring 1 (IRE1), PKR-like ER kinase (PERK), activating transcription factor 6 (ATF6)이 존재한다. 최근에 새로운 종류의 ATF6이 동정되었다. 이들은(Luman, OASIS, BBF2H7, CREBH, CREB4) 공통적으로 소포체막관통영역, 전사활성영역, bZIP영역을 가지며 특이조직과 세포내기관에서 기능을 가 진다. 현재로서는 OASIS family의 정확한 분자기전 설명은 어렵지만, 본 리뷰에서 이들 분자신호를 포괄적으로 소개할 것이다

• Nutrition Research and Practice
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• 제18권1호
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• pp.1-18
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• 2024

BACKGROUND/OBJECTIVES: Endoplasmic reticulum (ER) stress in adipose tissue causes an inflammatory response and leads to metabolic diseases. However, the association between vitamin D and adipose ER stress remains poorly understood. In this study, we investigated whether 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃) alleviates ER stress in adipocytes. MATERIALS/METHODS: 3T3-L1 cells were treated with different concentrations (i.e., 10-100 nM) of 1,25(OH)₂D₃ after or during differentiation (i.e., on day 0-7, 3-7, or 7). They were then incubated with thapsigargin (TG, 500 nM) for an additional 24 h to induce ER stress. Next, we measured the mRNA and protein levels of genes involved in unfold protein response (UPR) and adipogenesis using real-time polymerase chain reaction and western blotting and quantified the secreted protein levels of pro-inflammatory cytokines. Finally, the mRNA levels of UPR pathway genes were measured in adipocytes transfected with siRNA-targeting Vdr. RESULTS: Treatment with 1,25(OH)₂D₃ during various stages of adipocyte differentiation significantly inhibited ER stress induced by TG. In fully differentiated 3T3-L1 adipocytes, 1,25(OH)₂D₃ treatment suppressed mRNA levels of Ddit3, sXbp1, and Atf4 and decreased the secretion of monocyte chemoattractant protein-1, interleukin-6, and tumor necrosis factor-α. However, downregulation of the mRNA levels of Ddit3, sXbp1, and Atf4 following 1,25(OH)₂D₃ administration was not observed in Vdr-knockdown adipocytes. In addition, exposure of 3T3-L1 preadipocytes to 1,25(OH)₂D₃ inhibited transcription of Ddit3, sXbp1, Atf4, Bip, and Atf6 and reduced the p-alpha subunit of translation initiation factor 2 (eIF2α)/eIF2α and p-protein kinase RNA-like ER kinase (PERK)/PERK protein ratios. Furthermore, 1,25(OH)₂D₃ treatment before adipocyte differentiation reduced adipogenesis and the mRNA levels of adipogenic genes. CONCLUSIONS: Our data suggest that 1,25(OH)₂D₃ prevents TG-induced ER stress and inflammatory responses in mature adipocytes by downregulating UPR signaling via binding with Vdr. In addition, the inhibition of adipogenesis by vitamin D may contribute to the reduction of ER stress in adipocytes.

• Preventive Nutrition and Food Science
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• 제6권3호
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• pp.147-151
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• 2001

The combined effect of water-soluble chitosan oligomer and irradiation on changes in quality of perk sausage made with (156 ppm) or without NaNO$_{2}$ was determined. The pH of nonirradiated sausage without NaNO$_{2}$ decreased significantly during 3 wks of storage, but the pH of irradiated sausage did not. Irradiation at 4.5 kGy did not increase the Hunter color a-value but 10 and 20 kGy showed significantly higher a-values in the sausage with chitosan oligomer (p < 0.05). The sausage with NaNO$_{2}$ had higher sensory scores than that without NaNO$_{2}$, and irradiated sausage had lower scores in overall acceptance. Results indicate that further research is needed to achieve consumers sensory standards for irradiating cooked meat products.