• Biomolecules & Therapeutics
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• v.29 no.6
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• pp.615-629
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• 2021

An active compound, triterpene saponin, astersaponin I (AKNS-2) was isolated from Aster koraiensis Nakai (AKNS) and the autophagy activation and neuroprotective effect was investigated on in vitro and in vivo Parkinson's disease (PD) models. The autophagy-regulating effect of AKNS-2 was monitored by analyzing the expression of autophagy-related protein markers in SH-SY5Y cells using Western blot and fluorescent protein quenching assays. The neuroprotection of AKNS-2 was tested by using a 1-methyl-4-phenyl-2,3-dihydropyridium ion (MPP⁺)-induced in vitro PD model in SH-SY5Y cells and an MPTP-induced in vivo PD model in mice. The compound-treated SH-SY5Y cells not only showed enhanced microtubule-associated protein 1A/1B-light chain 3-II (LC3-II) and decreased sequestosome 1 (p62) expression but also showed increased phosphorylated extracellular signal-regulated kinases (p-Erk), phosphorylated AMP-activated protein kinase (p-AMPK) and phosphorylated unc-51-like kinase (p-ULK) and decreased phosphorylated mammalian target of rapamycin (p-mTOR) expression. AKNS-2-activated autophagy could be inhibited by the Erk inhibitor U0126 and by AMPK siRNA. In the MPP⁺-induced in vitro PD model, AKNS-2 reversed the reduced cell viability and tyrosine hydroxylase (TH) levels and reduced the induced α-synuclein level. In an MPTP-induced in vivo PD model, AKNS-2 improved mice behavioral performance, and it restored dopamine synthesis and TH and α-synuclein expression in mouse brain tissues. Consistently, AKNS-2 also modulated the expressions of autophagy related markers in mouse brain tissue. Thus, AKNS-2 upregulates autophagy by activating the Erk/mTOR and AMPK/mTOR pathways. AKNS-2 exerts its neuroprotective effect through autophagy activation and may serve as a potential candidate for PD therapy.

• BMB Reports
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• v.36 no.1
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• pp.12-19
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• 2003

Fragmentation of purine imidazole ring and production of formamidopyrimidines in deoxynucleosides (Fapy lesions) occurs upon DNA oxidation as well as upon spontaneous or alkali-triggered rearrangement of certain alkylated bases. Many chemotherapeutic agents such as cyclophosphamide or thiotepa produce such lesions in DNA. Unsubstituted FapyA and FapyG, formed upon DNA oxidation cause moderate inhibition of DNA synthesis, which is DNA polymerase and sequence dependent. Fapy-7MeG, a methylated counterpart of FapyG-, a efficiently inhibits DNA replication in vitro and in E.coli, however its mutagenic potency is low. This is probably due to preferential incorporation of cytosine opposite Fapy-7MeG and preferential extension of Fapy-7MeG:C pair. In contrast, FapyA and Fapy-7MeA possess miscoding potential. Both lesions in SOS induced E.coli preferentially mispair with cytosine giving rise to A$\rightarrow$G transitions. Fapy lesions substituted with longer chain alkyl groups also show simult aneous lethal and mutagenic properties. Fapy lesions are actively eliminated from DNA by repair glycosylases specific for oxidized purines and pyrimidines both in bacteria and eukaryotic cells. Bacterial enzymes include E.coli formamidopyrimidine-DNA-glycosylase (Fpg protein), endonuclease III (Nth protein) and endonuclease VIII (Nei protein).

• Journal of Sericultural and Entomological Science
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• v.33 no.1
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• pp.21-26
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• 1991

Bombyx mori nuclear polyhedrosis virus (BmNPV) was successfully multiplied in the nuclear of BmN4 cells cultured with insect Grace's medium. By electron microscopic observation, the virons had a single nucleocapsid in an envelope. Polyhedral protein synthesis of BmNPV in BmN4 cells was detected at 18 hr p.i. and polyhedral protein was a singlepolypeptide with a M.W of 30 kd. At 48 hr p.i. polyhedra formation was observed by inverted mociroscope and electron microscope. Genome analysis of BmNPV by restriction endonucleases was not revealed the difference between virus produced in vivo and that in vitro.

• Proceedings of the Ginseng society Conference
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• 1988.08a
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• pp.1-10
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• 1988

Previously. we reported that the intraperitoneal administration of ginseng crude saponin increased: (I) nuclear RNA polymerase activity. (2) nuclear RNA synthesis. (3) cytoplasmic RNA synthesis. (4) cytoplasmic heavy polyrioosome content. (5) amino acid incorporation in vitro of microsome and polysome isolated rat liver. and (6) the incorporation rate of labeled amino acids into serum protein. In addition, a spectacular increase in the rough endoplasmic reticulum of hepatocyte administered crude saponin for four weeks orally was shown through electron microscopy. An increase in polysomal content in membrane-hound ribosome was shown through ultracentrifugation. Recently, successive intraperitoneal. administration .of $ginsenosid-Rb_2$ was given to streptozotocin (STZ) diaoetic rats of hypoproteinemia. The blood urea nitrogen and hepatic urea concentration were decreased significantly. The total protein and alhumin levels in the serum were increased in comparison to control values. In contrast. the $ginsenoside-Rb_2$ treated group of STZ diahetic rats showed a significant increase in liver RNA. total ribosome and membrane-bound ribosomal contents. The administration of $ginsenoside-Rb_2$ increased the incorporation rate of labeled - precursor into total serum protein. Additionally $ginsenoside-Rb_2$ improved the nitrogen balance of diabetic rats. On the bases of these experimental results, ginseng saponin has a metabolic stimulatory or anabolic action on RNA and protein synthesis.

• Korean Journal of Ichthyology
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• v.12 no.3
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• pp.180-185
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• 2000

The effects of bisphenol-A(BPA), a monomer of plastics used in many consumer products, on vitellogenin(VTG) synthesis were examined in primary hepatocyte culture of olive flounder, Paralichthys olivaceus. The hepatocytes were precultured for 2 days, and then estradiol-$17\beta(10^{-6}M)$ and BPA were simultaneously added to the incubation medium. The hepatocytes were cultured for 6 more days and then spent medium was analyzed by SDS-PAGE. BPA increased the rate of VTG to total protein concentrations in a concentration-dependent way, and a significant difference was obtained at concentrations of $10^{-6}M$ and $10^{-5}M$ (P<0.05). In particular, the rate of VTG to total protein concentrations was 26.36% at $10^{-5}M$ of BPA, and its level did not differ from the control level with $E_2$ alone. $E_2$ and/or BPA-primed VTG synthesis was markedly inhibited to about 80% of the control(with $E_2$) by the addition of tamoxifen($10^{-6}M$) to the incubation medium. Furthermore, In vivo $E_2$-primed VTG synthesis was significantly inhibited by in vitro $E_2$-free incubation of hepatocyte to about 22% of the control (with $E_2$) on Day 6. The effect of reducing was delayed in a BPA concentration-dependent way. These results suggest that BPA induce VTG synthesis by estrogenic activity through estrogen receptor mediated response and prolong VTG synthesis on vitellogenesis in olive flounder.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.2
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• pp.146-153
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• 2006

A passive microfluidic delivery system using hydrophobic valving and pneumatic control was devised for microfluidic handling on a chip. The microfluidic metering, cutting, transport, and merging of two liquids on the chip were correctly performed. The error range of the accuracy of microfluid metering was below 4% on a 20 nL scale, which showed that microfluid was easily manipulated with the desired volume on a chip. For a study of the feasibility of biochemical reactions on the chip, a single enzymatic reaction, such as ${\beta}-galactosidase$ reaction, was performed. The detection limit of the substrate, i.e. fluorescein $di-{\beta}-galactopyranoside$ (FDG) of the ${\beta}-galactosidase$ (6.7 fM), was about 76 pM. Additionally, multiple biochemical reactions such as in vitro protein synthesis of enhanced green fluorescence protein (EGFP) were successfully demonstrated at the nanoliter scale, which suggests that our microfluidic chip can be applied not only to miniaturization of various biochemical reactions, but also to development of the microfluidic biochemical reaction system requiring a precise nano-scale control.

• The Plant Pathology Journal
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• v.28 no.2
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• pp.197-201
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• 2012

Potyviruses express their RNA genomes through the production of polyproteins that are processed in host cells by three virus-encoded proteases. Soybean plants produce large amounts of protease inhibitors during seed development and in response to wounding that could affect the activities of these proteases. The in vitro activities of two of the proteases of Soybean mosaic virus (SMV) and Tobacco vein mottling virus (TVMV) were compared in the rabbit reticulocyte lysate in vitro translation system using synthetic RNA transcripts. Transcripts produced from SMV and TVMV cDNAs that included the P1 and helper component-protease (HC-Pro) coding regions directed synthesis of protein products that were only partially processed. Unprocessed poly-proteins were not detected from transcripts that included all of the P1, HC-Pro, P3 and portions of the cylindrical inclusion protein coding regions of either virus. Addition of soybean trypsin inhibitor to in vitro translation reactions increased the accumulation of the unprocessed polyprotein from TVMV transcripts, but did not alter the patterns of proteins produced from SMV. These experiments suggest that SMV-and TVMV-encoded proteases are differentially sensitive to protease inhibitors.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.23 no.3
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• pp.9-23
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• 1997

Retinoids are essential regulators of spithelial cell growth and celluar differentiation. They are also known to be effective in photoaging. It was reported that topical application of retinoic acid improves facial wrinkle carsed by collagen synthesis reduction in photodamaged skin. Collagen synthesis by retinoic acid may contribute to the wrinkle effacement. Since celluar retinoic acid binding protein II is slsctively induced in human skin and dermal fibroblasts in vitro by retinoic acid, this response can be used to mesure retinoids potency and activity. In order to know the activity of retinoids and their relations with collagen synthesis, we treated dermal fibroblasts with retinoids for 48 hours at 10-6-10-7M and measured CRABPII mRNA level by quantitative Nortern blotting. We also measured the rate of collagen systhesis by retinoids using 3-dimensional dermal equivalent. CRABPII mRNA level was increased 3-fold by retinoic acid, 2.1-fold by retinol and 1.4-fold by retinaldehyde. Collagen systhesis was increased 34% by all-trans retinioc acid, 26% by retinol, 17% by retinaldehyde and 7% by retinyl palmitate. From the above results, retinoids were found to be a potent indecers of CRABPII mRNA and collagen synthesis. Though retinoic acid was the most effective, its use has been restricted because of the side effects. Instead, retinol can be a best candidate in cosmetics for the treatment of photodamaged skin in terms of efficacy and safety.

• 대한생식의학회:학술대회논문집
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• 1995.12a
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• pp.66.2-67
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• 1995

• Clinical and Experimental Reproductive Medicine
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• v.21 no.1
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• pp.111-119
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• 1994

"Spontaneous" hardening of the zona pellucida of mouse oocytes during in vitro culture is most likely due to cortical granules exocytosis. Thus the purpose of the present study was to determine whether the exocytosis factor is involved in spontaneous zona pellucida hardening during in vitro culture of the mouse. The results obtained form these experiments were summarized as follows; 1. When a protein synthesis inhibitor(100${\mu}g$/ml puromycin) was added to the culture medium, it did not prevent spontaneous ZPH of mouse oocyte during in vitro culture. 2. Calmodulin antagonists (trifluoperazine and chlorpromazine) and calcium channel blocker (verapamil) had no inhibitory effect in spontaneous ZPH. 3. A microtubule assembly inhibitor, colcemid had some inhibitory effect on spontaneous ZPH. 4. Treatment with a microfillament formation blocker(cytochalasin-B) at 1${\mu}g$/ml concentration, resulted in the excellent inhibitory effect on spontaneous ZPH. However cytochalasin-B did not inhibit ethanol-induced ZPH.