• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.11
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• pp.1589-1594
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• 2016

Piperine [(E,E)-5-(3,4-methtylenedioxyphenyl)-2,4-pentadienolypiperidide] is a principal of Piperaceae, including Piper nigrum L. and Piper longum Linn., which has been used as a spice and traditional medicine. In this study, we investigated whether or not piperine has anti-cancer effects on AGS human gastric cancer cells. The results demonstrated that piperine not only inhibited proliferation using MTT assay but also induced apoptotic bodies using DAPI assay in a dose-dependent manner in response to piperine. Expression levels of p53, Bax (pro-apoptotic), cleaved caspase-9, and cleaved-PARP increased, whereas expression levels of Bcl-2, XIAP (anti-apoptotic), and Akt decreased in a dose-dependent manner compared with the control by western blotting analysis. To identify the connection between phospo-Akt and Bcl-2 family in response to piperine, LY249002 (Akt inhibitor) was treated with piperine ($150{\mu}M$). The results were shown that expression of phospo-Akt was reduced whereas expression of Bax and cleaved-PARP increased in a dose-dependent manner. These results indicate that piperine induced apoptosis in AGS cells and may serve as a chemopreventive or therapeutic agent for human gastric cancer.

• Microbiology and Biotechnology Letters
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• v.42 no.2
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• pp.170-176
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• 2014

In this study, the anti-oxidative and anti-inflammatory activities of Euptelea pleiosperma ethanol extract (EPEE) were evaluated using in vitro assays and cell culture model systems. EPEE possessed a more potent scavenging activity against 1,1-diphenyl-2-picryl hydrazyl than the ascorbic acid used as a positive control. EPEE effectively suppressed lipopolysaccharide (LPS), in addition to hydrogen peroxide induced reactive oxygen species on RAW 264.7 cells. Furthermore, EPEE induced the expression of the anti-oxidative enzyme heme oxygenase 1 (HO-1) and its upstream transcription factor, nuclear factor-E2-related factor 2 (Nrf2), dose and time dependently. The modulation of HO-1 and Nrf2 expression might be regulated by mitogen-activated protein kinases and phosphatidyl inositol 3 kinase/Akt as their upstream signaling pathways. On the other hand, EPEE inhibited LPS induced nitric oxide (NO) formation without cytotoxicity. Suppression of NO formation was the result of the down regulation of inducible NO synthase (iNOS) by EPEE. Suppression of NO and iNOS by EPEE may be modulated by their upstream transcription factor, nuclear factor ${\kappa}B$, and AP-1 pathways. Taken together, these results provide important new insights into E. pleiosperma, namely that it possesses anti-oxidative and anti-inflammatory activities, indicating that it could be utilized as a promising material in the field of nutraceuticals.

• Journal of Life Science
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• v.29 no.4
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• pp.410-420
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• 2019

Citrus unshiu peel extracts possess a variety of beneficial effects, and studies on their anticancer activity have been reported. However, the exact mechanisms underlying this activity remain unclear. In the current study, the apoptotic effect of ethanol extract of C. unshiu peel (EECU) on human breast adenocarcinoma MDA-MB-231 cells and related mechanisms were investigated. The results showed that the survival rate of MDA-MB-231 cells treated with EECU was significantly inhibited in a concentration-dependent manner, which was associated with the induction of apoptosis. EECU-induced apoptosis was associated with the activation of caspase-8 and caspase-9, which initiate extrinsic and intrinsic apoptosis pathways, respectively, and caspase-3, a representative effect caspase. EECU suppressed the expression of the inhibitor of apoptosis family of proteins, leading to an increased Bax/Bcl-2 ratio and proteolytic degradation of poly (ADP-ribose) polymerase. EECU also enhanced the loss of the mitochondrial membrane potential and cytochrome c release from the mitochondria to the cytosol, along with truncation of Bid. In addition, EECU activated AMP-activated protein kinase (AMPK), and compound C, an AMPK inhibitor, significantly weakened EECU-induced apoptosis and cell viability reduction. Furthermore, EECU promoted the generation of reactive oxygen species (ROS), which acted as upstream signals for AMPK activation as pretreatment of cells, with the antioxidant N-acetyl cysteine reversing both EECU-induced AMPK activation and apoptosis. Collectively, these findings suggest that EECU inhibits MDA-MB-231 adenocarcinoma cell proliferation by activating intrinsic and extrinsic apoptotic pathways, which was mediated through ROS/AMPK-dependent pathways.

• Journal of Life Science
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• v.29 no.4
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• pp.402-409
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• 2019

Korean red ginseng made from steaming and drying fresh ginseng has long been used as a traditional herbal medicine due to its effects on the immune, endocrine, and central nerve systems and its anti-inflammatory activity. In this study, we investigated the molecular mechanism responsible for the anti-inflammatory effects of a formulated Korean red ginseng extract (RGE) in response to lipoteichoic acid (LTA), a cell wall component of gram-positive bacteria. RGE inhibited LTA-induced nitric oxide (NO) secretion and inducible nitric oxide synthase (iNOS) expression in BV-2 microglial cells, without affecting cell viability. RGE also inhibited nuclear translocation of nuclear factor kappa B ($NF-{\kappa}B$) p65 and degradation of $I{\kappa}B-{\alpha}$. In addition, RGE increased the expression of heme oxygenase-1 (HO-1) in a dose-dependent manner, and the inhibitory effect of RGE on iNOS expression was abrogated by small interfering RNA-mediated knockdown of HO-1. Moreover, RGE induced nuclear translocation of nuclear factor E2-related factor 2 (Nrf2), a transcription factor that regulates HO-1 expression. Furthermore, the phosphoinositide-3-kinase (PI-3K) inhibitor and mitogen-activated protein kinase (MAPK) inhibitors suppressed RGE-mediated expression of HO-1, and RGE enhanced the phosphorylation of Akt, extracellular signal-regulated kinases (ERKs), p38, and c-JUN N-terminal kinases (JNKs). These results suggested that RGE suppressed the production of NO, a proinflammatory mediator, by inducing HO-1 expression via PI-3K/Akt- and MAPK-dependent signaling in LTA-stimulated microglia. The findings indicate that RGE could be used for the treatment of neuroinflammation induced by grampositive bacteria and that it may have therapeutic potential for various neuroinflammation-associated disorders.

• Journal of Life Science
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• v.32 no.2
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• pp.108-118
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• 2022

The subventricular zone (SVZ) in the brain contains neural stem cells (NSCs) that generate new neurons throughout one's lifetime. Many extracellular and intracellular factors that affect cell proliferation and neuronal differentiation of NSCs are already well-known. Recently, L-type calcium channels have been reported to regulate neural development and are present in NSCs, differentiating neuroblasts, and mature neurons in the SVZ. Nifedipine, a blocker of L-type calcium channels, has been long used as a therapeutic drug for hypertension. However, studies on the use of nifedipine to inhibit L-type calcium channels of NSCs are lacking. Herein, we treated NSCs cultured from mouse postnatal SVZ with nifedipine during neuronal differentiation. Nifedipine increased the number of Tuj1-positive neurons but did not significantly change the number of Olig2-positive oligodendrocytes. Nifedipine increased cell division during early differentiation, which was detected using the 5-ethynyl-2'-deoxyuridine incorporation assay and immunocytochemistry assessment by staining the cells with phosphorylated histone H3, a mitosis marker. Nifedipine increased the transcription of Dlx2, a neurogenic transcription factor, and the level of Mash1, a marker for early neurogenesis. In addition to nifedipine, verapamil, which is also an L-type calcium channel blocker, showed a slight increase in neurogenesis, but its statistical significance was very low. In contrast, pimozide, a T-type calcium channel blocker, did not affect neurogenesis, although T-type calcium channel genes Cav3.1, Cav3.2, and Cav3.3 were expressed. In summary, nifedipine might promote the neuronal fate of NSCs during early differentiation and calcium signaling through L-type calcium channels might be involved in neuronal differentiation, especially during the early stages of differentiation.

• Development and Reproduction
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• v.12 no.3
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• pp.289-296
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• 2008

BPES (Blepharophimosis/Ptosis/Epicanthus inversus Syndrome) is an autosomal dominant disorder caused by mutations in FOXL2. Affected individuals have premature ovarian failure (POF) in addition to small palpebral fissures, drooping eyelids, and broad nasal bridge. FOXL2 is a member of the forkhead family transcription factors. In FOXL2-deficient ovaries, granulosa cell differentiation dose not progress, leading to arrest of folliculogenesis and oocytes atresia. Using yeast two-hybrid screening of rat ovarian cDNA library with FOXL2 as bait, we found that small ubiquitin-related modifier (SUMO)-conjugating E2 enzyme UBE2I protein interacted with FOXL2 protein. UBE2I also known as UBC9 is an essential protein for processing SUMO modification. Sumoylation is a form of post-translational modification involved in diverse signaling pathways including the regulation of transcriptional activities of many transcriptional factors. In the present study, we confirmed the protein-protein interaction between FOXL2 and UBE2I in human cells, 293T, by in vivo immunoprecipitation. In addition, we generated truncated FOXL2 mutants and identified the region of FOXL2 required for its association with UBE2I using yeast-two hybrid system. Therefore, the identification of UBE2I as an interacting protein of FOXL2 further suggests a presence of novel regulatory mechanism of FOXL2 by sumoylation.

• Tuberculosis and Respiratory Diseases
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• v.49 no.3
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• pp.310-322
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• 2000

Background : Phospholipase C(PLC) plays an important role in cellular signal transduction and is thought to be critical in cellular growth, differentiation and transformation of certain malignancies. Two second messengers produced from the enzymatic action of PLC are diacylglycerol (DAG) and inositol 1, 4, 5-trisphosphate (IP3). These two second messengers are important in down stream signal activation of protein kinase C and intracellular calcium elevation. In addition, functional domains of the PLC isozymes, such as Src homology 2 (SH2) domain, Src homology 3 (SH3) domain, and pleckstrin homology (PH) domain play crucial roles in protein translocation, lipid membrane modificailon and intracellular memrane trafficking which occur during various mitogenic processes. We have previously reported the presence of PLC-${\gamma}1$, ${\gamma}2$, ${\beta}1$, ${\beta}3$, and ${\delta}1$ isozymes in normal human lung tissue and tyrosine-kinase-independent activation of phospholipase C-${\gamma}$ isozymes by tau protein and AHNAK. We had also found that the expression of AHNAK protein was markedly increased in various mstologic types of lung can∞r tissues as compared to the normallungs. However, the report concerning expression of various PLC isozymes in lung canærs and other lung diseases is lacking. Therefore, in this study we examined the expression of PLC isozymes in the paired surgical specimens taken from lung cancer patients. Methods : Surgically resected lung cancer tissue samples taken from thirty seven patients and their paired normal control lungs from the same patients, The expression of various PLC isozymes were studied. Western blot analysis of the tissue extracts for the PLC isozymes and immunohistochemistry was performed on typical samples for localization of the isozyme. Results : In 16 of 18 squamous cell carcinomas, the expression of PLC-${\gamma}1$ was increased. PLC-${\gamma}1$ was also found to be increased in all of 15 adenocarcinoma patients. In most of the non-small cell lung cancer tissues we had examined, expression of PLC-${\delta}1$ was decreased. However, the expression of PLC-${\delta}1$ was markedly increased in 3 adenocarcinomas and 3 squamous carcinomas. Although the numbers were small, in all 4 cases of small cell lung cancer tissues, the expression of PLC-${\delta}1$ was nearly absent. Conclusion : We found increased expression of PLC-${\gamma}1$ isozyme in lung cancer tissues. Results of this study, taken together with our earlier findings of AHNAK protein-a putative PLD-${\gamma}$, activator-over-expression, and the changes observed in PLC-${\delta}1$ in primary human lung cancers may provide a possible insight into the derranged calcium-inositol signaling pathways leading to the lung malignancies.

• Journal of Life Science
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• v.30 no.9
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• pp.804-812
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• 2020

The giant mealworm beetle, Zophobas atratus (Coleoptera: Tenebrionidae) has been used as a protein source for small pets and mammals. Recently, it was temporarily registered in the list of the Food Code. We previously performed an in silico analysis of the Zophobas atratus transcriptome to identify putative antimicrobial peptides and identified several antimicrobial peptide candidates. Among them, we assessed the antimicrobial and anti-inflammatory activities of zophobacin 1 that was selected bio-informatically based on its physicochemical properties against microorganisms and mouse macrophage Raw264.7 cells. Zophobacin 1 showed antimicrobial activities against microorganisms without inducing hemolysis and decreased the nitric oxide production of the lipopolysaccharide-induced Raw264.7 cells. Moreover, ELISA and Western blot analysis revealed that zophobacin 1 reduced expression levels of pro-inflammatory enzymes such as inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). We also investigated expression of pro-inflammatory cytokines (interleukin-6 and interleukin-1β) production through quantitative real time-PCR and ELISA. Zophobacin 1 markedly reduced the expression level of cytokines through the regulation of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling. We confirmed that zophobacin 1 bound to bacterial cell membranes via a specific interaction with lipopolysaccharides. These data suggest that zophobacin 1 could be promising molecules for development as antimicrobial and anti-inflammatory therapeutic agents.

• Journal of Life Science
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• v.30 no.1
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• pp.10-17
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• 2020

Kinesin-1 is microtubule-dependent plus-end direct molecular motor protein essential for intracellular transport. It is a member of the kinesin superfamily proteins (KIFs) which transport cargo, including organelles, vesicles, neurotransmitter receptors, cell-signaling molecules, and protein complexes through interaction between its light chain subunit and the cargo. Kinesin light chain 1 (KLC1) is a non-motor subunit that associates with the kinesin heavy chain (KHC). Although KLC1 interacts with many different adaptor proteins and scaffolding proteins, its binding proteins have not yet been fully identified. We used the yeast two-hybrid assay to identify proteins that interact with the tetratricopeptide repeat (TPR) domain of KLC1, and found an interaction between KLC1 and EH domain-binding protein 1 like 1 (EHBP1L1). EHBP1L1 bound to the region containing all six TPR repeats of KLC1 and did not interact with KIF5B (a motor protein of kinesin 1) or KIF3A (a motor protein of kinesin 2) in the yeast two-hybrid assay. The carboxyl-terminus of the coiled-coil domain of EHBP1L1 is essential for interaction with KLC1. However, another EHBP1L1 isoform, EHBP1, did not interact with KLC1 in the yeast two-hybrid assay. KLC1 interacted with GST-EHBP1L1 and its coiled-coil domain but not with GST only. When co-expressed in HEK-293T cells, EHBP1L1 co-localized with KLC1 and co-immunoprecipitated with KLC1 and KIF5B but not KIF3A. These results suggest that kinesin 1 motor protein may transport EHBP1L1-associated cargo in cells.

• Applied Microscopy
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• v.30 no.4
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• pp.347-355
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• 2000

Zinc is one of the most abundant oligoelements in the living cell. It appears tightly bound to some metalloproteins and nucleic acids, loosely bound to some metallothioneins or even as free ion. Small amounts of zinc ions (in the nanomolar range) regulate a plentitude of enzymatic proteins, receptors and transcription factors, thus rolls need accurate homeostasis of zinc ions. Zinc is an essential catalytic or structural element of many proteins, and a signaling messenger that is released by neural activity at many central excitatory synapses. Growing evidences suggest that zinc may also be a key mediator and modulator of the neuronal death associated with transient global ischemia and sustained seizures, as well as perhaps other neurological disease stoles. Some neurons have developed mechanisms to accumulate zinc in specific membrane compartment ('vesicular zinc') which can be evidenced using histochemical techniques. Substances giving a bright colour or emitting fluorescence when in contact with divalent metal ions are currently used to detect them inside cells; their use leads to the so called 'direct' methods. The fixation and precipitation of metal ions as insoluble salt precipitates, their maintenance along the histological process and, finally, their demonstration after autometallographic development are essential steps for other methods, the so called 'indirect methods'. This study is a short report on the autometallograhical approaches for zinc detection in the central nervous system (CNS) by means of a modified selenium method.