• Parasites, Hosts and Diseases
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• v.56 no.1
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• pp.81-86
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• 2018

Four isoforms of calcium binding proteins containing 2 EF hand motifs and a dynein light chain-like domain in the human liver fluke Opisthorchis viverrini, namely OvCaBP1, 2, 3, and 4, were characterized. They had molecular weights of 22.7, 21.6, 23.7, and 22.5 kDa, respectively and showed 37.2-42.1% sequence identity to CaBP22.8 of O. viverrini. All were detected in 2- and 4-week-old immature and mature parasites. Additionally, OvCaBP4 was found in newly excysted juveniles. Polyclonal antibodies against each isoform were generated to detect the native proteins in parasite extracts by Western blot analysis. All OvCaBPs were detected in soluble and insoluble crude worm extracts and in the excretory-secretory product, at approximate sizes of 21-23 kDa. The ion-binding properties of the proteins were analyzed by mobility shift assays with the divalent cations $Ca^{2+}$, $Mg^{2+}$, $Zn^{2+}$, and $Cu^{2+}$. All OvCaBPs showed mobility shifts with $Ca^{2+}$ and $Zn^{2+}$. OvCaBP1 showed also positive results with $Mg^{2+}$ and $Cu^{2+}$. As tegumental proteins, OvCaBP1, 2, and 3 are interesting drug targets for the treatment of opisthorchiasis.

• Journal of Microbiology and Biotechnology
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• v.30 no.2
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• pp.178-186
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• 2020

Licorice (Glycyrrhiza uralensis) contains several compounds that have been reported to alleviate menopausal symptoms via interacting with estrogen receptors (ERs). The compounds exist mainly in the form of glycosides, which exhibit low bioavailability and function. To bioconvert liquiritin and isoliquiritin, the major estrogenic compounds, to the corresponding deglycosylated liquiritigenin and isoliquiritigenin, respectively, licorice was fermented with Monascus, which has been demonstrated to deglycosylate other substances. The contents of liquiritigenin and isoliquiritigenin in Monascus-fermented licorice increased by 10.46-fold (from 38.03 μM to 379.75 μM) and 12.50-fold (from 5.53 μM to 69.14 μM), respectively, compared with their contents in non-fermented licorice. Monascus-fermented licorice exhibited 82.5% of the ERβ binding activity of that observed in the positive control (17 β-estradiol), whereas the non-fermented licorice exhibited 54.1% of the binding activity in an in vivo ER binding assay. The increase in the ERβ binding activity was associated with increases in liquiritigenin and isoliquiritigenin contents. Liquiritigenin acts as a selective ligand for ERβ, which alleviates menopausal symptoms with fewer side effects, such as heart disease and hypertension, compared with a ligand for ERα. In addition, Monascus-fermented licorice contained 731 mg/kg of monacolin K, one of the metabolites produced by Monascus that reduces serum cholesterol. Therefore, Monascus-fermented licorice is a promising material for the prevention and treatment of menopausal syndrome with fewer side effects.

• Journal of Veterinary Clinics
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• v.21 no.3
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• pp.253-258
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• 2004

DNA double-strand break (DSB) is a serious treat for the cells including mutations, chromosome rearrangements, and even cell death if not repaired or misrepaired. Ku heterodimer regulatory DNA binding subunits (Ku70/Ku80) bound to double strand DNA breaks are able to interact with 470-kDa DNA-dependent protein kinase catalytic subunit (DNA-PKcs), and the interaction is essential for DNA-dependent protein kinase (DNA-PK) activity. The Ku80 mutants were designed to bind Ku70 but not DNA end binding activity and the peptides were treated in breast cancer cells for co-therapy strategy to see whether the targeted inhibition of DNA-dependent protein kinase (DNA-PK) activity sensitized breast cancer cells to ionizing irradiation or chemotherapy drug to develop a treatment of breast tumors by targeting proteins involved in damage-signaling pathway and/or DNA repair. We designed domains of Ku80 mutants, 26 residues of amino acids (HN-26) as a control peptide or 38 (HNI-38) residues of amino acids which contain domains of the membrane-translocation hydrophobic signal sequence and the nuclear localization sequence, but HNI-38 has additional twelve residues of peptide inhibitor region. We observed that the synthesized peptide (HNI-38) prevented DNA-PKcs from binding to Ku70/Ku80, resulting in inactivation of DNA-PK complex activity in breast cancer cells (MDA-465 and MDA-468). Consequently, the peptide treated cells exhibited poor to no DNA repair, and became highly sensitive to irradiation or chemotherapy drugs. The growth of breast cancer cells was also inhibited. These results demonstrate the possibility of synthetic peptide to apply breast cancer therapy to induce apoptosis of cancer cells.

• The Korean Journal of Physiology and Pharmacology
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• v.4 no.6
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• pp.507-513
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• 2000

ErbB3/HER3 is a cell surface receptor which belongs to the ErbB/HER subfamily of receptor protein tyrosine kinases. When expressed in NIH/3T3 cells, ErbB3 can form heterodimeric coreceptor with endogenous ErbB2. Among known intracellular effectors of the ErbB2/ErbB3 are mitogen-activated protein kinase (MAPK) and phosphoinositide (PI) 3-kinase. In the present study, we studied relative contributions of above two distinct signaling pathways to the heregulin-induced mitogenic response via activated ErbB3. For this, clonal NIH-3T3 cell lines expressing wild-type ErbB3 and ErbB3 mutants were stimulated with $heregulin{\beta}_1$. While cyclin D1 level was markedly high and further increased by treatment of heregulin in cells expressing wild-type ErbB3, the elimination of either Shc binding or PI 3-kinase binding lowered both levels. This result was supported by the reduction of cyclin $D_1$ expression by preteatment with MAPK kinase inhibitor or PI 3-kinase inhibitor before stimulation with heregulin. In accordance with the cyclin $D_1$ expression, elimination of either Shc binding or PI 3-kinase binding reduced the heregulin-induced DNA synthesis and cell growth rate. Our results obtained by the comparison of wild-type and ErbB3 mutants indicate that the full induction of the cell cycle progression through $G_1/S$ phase by ErbB3 activation is dependent on both Shc/MAPK and PI 3-kinase signal transduction pathways.

• Molecules and Cells
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• v.41 no.10
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• pp.909-916
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• 2018

In pancreatic ${\beta}$ cells, glucose stimulates the biosynthesis of insulin at transcriptional and post-transcriptional levels. The RNA-binding protein, polypyrimidine tract-binding protein 1 (PTBP1), also named hnRNP I, acts as a critical mediator of insulin biosynthesis through binding to the pyrimidine-rich region in the 3'-untranslated region (UTR) of insulin mRNA. However, the underlying mechanism that regulates its expression in ${\beta}$ cells is unclear. Here, we report that glucose induces the expression of PTBP1 via the insulin receptor (IR) signaling pathway in ${\beta}$ cells. PTBP1 is present in ${\beta}$ cells of both mouse and monkey, where its levels are increased by glucose and insulin, but not by insulin-like growth factor 1. PTBP1 levels in immortalized ${\beta}$ cells established from wild-type (${\beta}IRWT$) mice are higher than levels in ${\beta}$ cells established from IR-null (${\beta}IRKO$) mice, and ectopic re-expression of IR-WT in ${\beta}IRKO$ cells restored PTBP1 levels. However, PTBP1 levels were not altered in ${\beta}IRKO$ cells transfected with IR-3YA, in which the Tyr1158/1162/1163 residues are substituted with Ala. Consistently, treatment with glucose or insulin elevated PTBP1 levels in ${\beta}IRWT$ cells, but not in ${\beta}IRKO$ cells. In addition, silencing Akt significantly lowered PTBP1 levels. Thus, our results identify insulin as a pivotal mediator of glucose-induced PTBP1 expression in pancreatic ${\beta}$ cells.

• Parasites, Hosts and Diseases
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• v.46 no.4
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• pp.243-246
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• 2008

Bla g 2 is a cockroach allergen of great importance, This study was conducted to identify IgE-binding epitope(s) of Bla g 2 using the recombinant protein technique, Approximately 50% of tested sera showed IgE reactivity to Pichia-expressed Bla g 2 (PrBla g 2) and E. coli-expressed Bla g 2 (ErBla g 2), Only 5,3% of serum samples showed stronger reactivity to PrBla g 2 than ErBla g 2, indicating that serum was reactive to conformational or carbohydrate epitopes. The full-length and 5 peptide fragments of Bla g 2 were produced in E. coli. All fragments showed IgE-binding activity to the cockroach-allergy patients' sera. Specifically, peptide fragments of amino acid residue 1-75 and 146-225 appeared to be important for IgE-binding. The information about the IgE-binding epitope of Bla g 2 can aid in the diagnosis and treatment for cockroach allergies.

• Journal of Ginseng Research
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• v.13 no.1
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• pp.37-41
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• 1989

Reactive metabolites generated by benzo(a)pyrene(BP) monooxygenase(AHH) interact with nucleophiles in DNA and cause mutation and carcinogenesis. We studied the effect of Panax ginseng C.A. Meyer, which induce epoxide hydratase(EH) activity without concomitant induction of AHH activity, on the binding of BP metabolites to DNA in uitro in Sprague Dawley rats. DNA-BP metabolite adducts can be resolved into at least five distinct peaks by elution of a Sephadex LH-20 column with a water methanol gradieNt. These peaks are arbitrarily designated A(most polar) through I(least polar). Of the 5 peaks tentatively assigned to 7,8 biol-9,10-oxide(A),7,8·oxide(B),4,5-oxide(C), and further metabolites of 9-OH-BP(D & E), peaks A, C, D, and I were reduced to 70, 85, 80, and 30% of controls, respectively, and there was no significant change in peak B. In connection with this DNA binding study, BP metabolizing enzymes including AHH, EH, demethylase(DM) activity and cyt. P-450 contents were also investigated in order to compare the BP treated control with ginseng and BP treated test groups. The results showed that the EH activity was increased by 139% over the BP control, the Cyt. P-450 content was increased by 180% over the control value, and DM and AHH activities were also increased to some degree for the BP test group, but there was no significant effect of the ginseng treatment.

• Animal cells and systems
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• v.16 no.2
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• pp.87-94
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• 2012

Nur77 is a member of the nuclear receptor 4A (NR4A) subgroup, which has been implicated in energy metabolism. Although Nur77 is found in adipose tissue, where TR4 plays a key role in lipid homeostasis, the role of Nur77 in adipogenesis is still controversial. Although the Nur77 responsive element (AAAGGTCA) is partially overlapped with TR4-binding sites (AGGTCA $n$ AGGTCA: $n$=0-6), the regulatory role of Nur77 in TR4 function associated with adipocyte biology remains unclear. Here, we found that Nur77 inhibits adipogenesis and TR4 transcriptional activity. Treatment with a Nur77 agonist, 1,1-bis(3'-indolyl)-1-($p$-anisyl)-methane, during 3T3-L1 adipocyte differentiation reduced adipogenesis. In reporter gene analysis, Nur77 specifically suppressed TR4 transcription activity but had little effect on $PPAR{\gamma}$ transcription activity. Consistently, Nur77 also suppressed TR4-induced promoter activity of the TR4 target gene PEPCK, which is known to be important for glyceroneogenesis in adipose tissue. Furthermore, Nur77 suppressed TR4 binding to TR4 response elements without direct interaction with TR4, suggesting that Nur77 may inhibit TR4 transcription activity via binding competition for TR4-binding sites. Furthermore, DIM-C-$pPhOCH_3$ substantially suppressed TR4-induced PEPCK expression in 3T3-L1 adipocytes. Together, our data demonstrate that Nur77 plays an inhibitory role in TR4-induced PEPCK expression in 3T3-L1 adipocytes.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.4
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• pp.229-233
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• 2010

Amyloid precursor protein binding protein-1 (APP-BP1) binds to the carboxyl terminus of amyloid precursor protein and serves as a bipartite activation enzyme for the ubiquitin-like protein, NEDD8. Previously, it has been reported that APP-BP1 rescues the cell cycle S-M checkpoint defect in Ts41 hamster cells, that this rescue is dependent on the interaction of APP-BP1 with hUba3. The exogenous expression of APP-BP1 in neurons has been reported to cause DNA synthesis and apoptosis via a signaling pathway that is dependent on APP-BP1 binding to APP. These results suggest that APP-BP1 overexpression contributes to neurodegeneration. In the present study, we explored whether APP-BP1 expression was altered in the brains of Tg2576 mice, which is an animal model of Alzheimer's disease. APP-BP1 was found to be up-regulated in the hippocampus and cortex of 12 month-old Tg2576 mice compared to age-matched wild-type mice. In addition, APP-BP1 knockdown by siRNA treatment reduced cullin-1 neddylation in fetal neural stem cells, suggesting that APP-BP1 plays a role in cell cycle progression in the cells. Collectively, these results suggest that increased expression of APP-BP1, which has a role in cell cycle progression in neuronal cells, contributes to the pathogenesis of Alzheimer's disease.

• Bulletin of the Korean Chemical Society
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• v.23 no.12
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• pp.1773-1777
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• 2002

Reactive oxygen species(ROS) have been investigated to have pivotal roles on amyloidogenecity of $\beta-amyloidpeptide(A\beta)$, the major component of senile plaques in Alzheimer's disease(AD) brain. Addition of radical scavengers is one of the on-going strategies for therapeutic treatment for AD patients. Hsp104 protein including two ATP binding sites from Saccharomyces cerevisiae, as a molecular chaperone, was known to function as a protector of ROS generation when exposed to oxidative stress in our previous study. This observation has led us to investigate Hsp104 protein as a molecular mediator of $A{\beta}$ aggregation in this study. We have developed a new way of expression for Hsp104 protein using GST-fusion tag. As we expected, formation of $A{\beta}$ aggregate was protected by wild type Hsp104 protein, but not by the two ATP-binding site mutant, based on Thioflavin-T fluorescence. Interestingly, Hsp104 protein was observed to keep $A{\beta}$ from forming aggregates independent of ATP binding. On the other hand, disaggregation of $A{\beta}$ aggregates by wild type Hsp104 was totally dependent on the presence of ATP. On the other hand, mutant Hsp104 with two ATP binding sites altered exhibited no inhibition. Another effective antioxidant, hydrazine analogs of curcumin were also effective in $A{\beta}$ fibrilization as protectors against oxidative stress. Based on these observations we conclude that Hsp104 and curcumin derivatives, as protectors of oxidative stress, inhibit $A{\beta}$ aggregation in virto and can be candidates for therapeutic approaches in cure of some neurodegenerative disease.