• Journal of Ginseng Research
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• v.37 no.4
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• pp.401-412
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• 2013

Korean Red Ginseng (KRG) is an oriental herbal preparation obtained from Panax ginseng Meyer (Araliaceae). To expand our understanding of the action of KRG on central nervous system (CNS) function, we examined the effects of KRG on tissue plasminogen activator (tPA)/plasminogen activator inhibitor-1 (PAI-1) expression in rat primary astrocytes. KRG extract was treated in cultured rat primary astrocytes and neuron in a concentration range of 0.1 to 1.0 mg/mL and the expression of functional tPA/PAI-1 was examined by casein zymography, Western blot and reverse transcription-polymerase chain reaction. KRG extracts increased PAI-1 expression in rat primary astrocytes in a concentration dependent manner (0.1 to 1.0 mg/mL) without affecting the expression of tPA itself. Treatment of 1.0 mg/mL KRG increased PAI-1 protein expression in rat primary astrocytes to $319.3{\pm}65.9%$ as compared with control. The increased PAI-1 expression mediated the overall decrease in tPA activity in rat primary astrocytes. Due to the lack of PAI-1 expression in neuron, KRG did not affect tPA activity in neuron. KRG treatment induced a concentration dependent activation of PI3K, p38, ERK1/2, and JNK in rat primary astrocytes and treatment of PI3K or MAPK inhibitors such as LY294002, U0126, SB203580, and SP600125 (10 ${\mu}M$ each), significantly inhibited 1.0 mg/mL KRG-induced expression of PAI-1 and down-regulation of tPA activity in rat primary astrocytes. Furthermore, compound K but not other ginsenosides such as Rb1 and Rg1 induced PAI-1 expression. KRG-induced up-regulation of PAI-1 in astrocytes may play important role in the regulation of overall tPA activity in brain, which might underlie some of the beneficial effects of KRG on CNS such as neuroprotection in ischemia and brain damaging condition as well as prevention or recovery from addiction.

• Molecules and Cells
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• v.45 no.3
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• pp.112-121
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• 2022

Calorie restriction (CR) and the activation of autophagy extend healthspan by delaying the onset of age-associated diseases in most living organisms. Because protein kinase CK2 (CK2) downregulation induces cellular senescence and nematode aging, we investigated CK2's role in CR and autophagy. This study indicated that CR upregulated CK2's expression, thereby causing SIRT1 and AMP-activated protein kinase (AMPK) activation. CK2α overexpression, including antisense inhibitors of miR-186, miR-216b, miR-337-3p, and miR-760, stimulated autophagy initiation and nucleation markers (increase in ATG5, ATG7, LC3BII, beclin-1, and Ulk1, and decrease in SQSTM1/p62). The SIRT1 deacetylase, AKT, mammalian target of rapamycin (mTOR), AMPK, and forkhead homeobox type O (FoxO) 3a were involved in CK2-mediated autophagy. The treatment with the AKT inhibitor triciribine, the AMPK activator AICAR, or the SIRT1 activator resveratrol rescued a reduction in the expression of lgg-1 (the Caenorhabditis elegans ortholog of LC3B), bec1 (the C. elegans ortholog of beclin-1), and unc-51 (the C. elegans ortholog of Ulk1), mediated by kin-10 (the C. elegans ortholog of CK2β) knockdown in nematodes. Thus, this study indicated that CK2 acted as a positive regulator in CR and autophagy, thereby suggesting that these four miRs' antisense inhibitors can be used as CR mimetics or autophagy inducers.

• Journal of Life Science
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• v.13 no.1
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• pp.99-104
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• 2003

Aromatic compounds are of major concern among environmental pollutants due to their toxicity and persistence. To monitor aromatic compounds in a real time with a better sensitivity, a new method of SPR (surface plasmon resonance) based on DNA chip (Biacore 3000) was developed here. It is thought that CapR regulatory protein as a complex with phenol, could bind to their corresponding promoter, Po. Biotinylated DNA oligomers for the promoter was synthesized by PCR and coupled onto streptoavidin-linked CM5-chip. CapR regulatory proteins were purified after cloning their genes in pET21a (+) vector and expressing proteins. The interaction was assessed by the system where the regulatory proteins flowed with or without phenol through the cells of DNA chip. CapR regulatory protein even in the presence of phenol had no response to its promoter, Po, suggesting that other factor(s) might be required for the activation of Po promoter. The present work reveals a promising possibility of the SPR-based DNA chip in monitoring specific environmental pollutants in a real time.

• Animal Bioscience
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• v.35 no.9
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• pp.1444-1453
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• 2022

Objective: Acetate plays an important role in host lipid metabolism. However, the network of acetate-regulated lipid metabolism remains unclear. Previous studies show that mitogen-activated protein kinases (MAPKs) and mechanistic target of rapamycin (mTOR) play a crucial role in lipid metabolism. We hypothesize that acetate could affect MAPKs and/or mTOR signaling and then regulate lipid metabolism. The present study investigated whether any cross talk occurs among MAPKs, mTOR and acetate in regulating lipid metabolism. Methods: The ceramide C6 (an extracellular signaling-regulated kinases 1 and 2 [ERK1/2] activator) and MHY1485 (a mTOR activator) were used to treat rabbit adipose-derived stem cells (ADSCs) with or without acetate, respectively. Results: It indicated that acetate (9 mM) treatment for 48 h decreased the lipid deposition in rabbit ADSCs. Acetate treatment decreased significantly phosphorylated protein levels of ERK1/2 and mTOR but significantly increased mRNA level of hormone-sensitive lipase (HSL). Acetate treatment did not significantly alter the phosphorylated protein level of p38 MAPK and c-Jun aminoterminal kinase (JNK). Activation of ERK1/2 and mTOR by respective addition in media with ceramide C6 and MHY1485 significantly attenuated decreased lipid deposition and increased HSL expression caused by acetate. Conclusion: Our results suggest that ERK1/2 and mTOR signaling pathways are associated with acetate regulated HSL gene expression and lipid deposition.

• Reproductive and Developmental Biology
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• v.28 no.3
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• pp.187-190
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• 2004

Protein kinase C exists as a family of serine/threonine kinases which are broadly classified into three groups as cPKC nPKC and aPKC depending on their cofactor requirements. Previous studies have shown that the role of PKC in the process of mouse oocyte maturation. For example, phorbol 12-myristate 13-acetate which is known as an activator of cPKC and nPKC inhibits germinal vesicle break down and 1st polar body extrusion in maturing oocytes. In this study, the effect of thymeleatoxin, a specific activator of cPKC not nPKC, was tested comparing with PMA to address the roles of cPKC and nPKC during mouse oocyte maturation. Cumulus-oocyte complex were cultured in M16 medium for 6 or 12 hr with each of these PKC activators to investigate the effect of germinal vesicle breakdown (GVBD) or the extrusion of 1st polar body. IC/sup 50/ of GVBD were at concentrations of 50nM in PMA and 400nM in thymeleatoxin and of 1st polar body extrusion were 20nM in PMA and 200nM in thy- meleatoxin. The results suggest that activation of nPKC is more closely related to the inhibition of GVBD and 1st polar body extrusion than activation of cPKC. Additionally, we found that the oocytes inhibited 1st polar body extrusion with PMA or thymeleatoxin were arrested in metaphase I of first meiosis.

• The Journal of Internal Korean Medicine
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• v.34 no.2
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• pp.204-214
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• 2013

Objectives : This study was designed to investigate the cellular and molecular mechanisms of anti-inflammatory activity of the water extract of Polygala tenuifolia Willd. (Pt-WE). Methods : Using lipopolysaccharide (LPS)-stimulated murine RAW264.7 cells, we examined inflammatory mediators such as nitric oxide (NO), inducible NO synthase (iNOS), cyclooxygenase (COX)-2 and prostaglandin $E_2$ ($PGE_2$). Also, the inhibitory effect of Pt-WE on the activity of activator protein 1 (AP-1) and upstream signaling molecules was evaluated. To assess the protective effect of Pt-WE on hydrochloride/ethanol (HCl/EtOH)-induced gastric ulcer in mice, we compared Pt-WE (200 mg/kg) with ranitidine (50 mg/kg) treated mice's gastric mucosa, based on gross observations. Results : Pt-WE inhibited LPS-induced production of NO, $PGE_2$ in a dose-dependent manner, without causing cytotoxicity. Pt-WE suppressed AP-1 activation by reducing generations of both c-Jun and c-Fos. In addition, Pt-WE inhibited the p-MKK 4/7 (mitogen-activated protein kinase kinase 4/7) and p-JNK (c-Jun N-terminal kinase) 1 in LPS-stimulated RAW264.7 cells. HCl/EtOH-induced gastric ulcer lesions were inhibited by pre-treatment of Pt-WE based on gross observations. In addition, Pt-WE decreased the phosphorylation level of JNK. Conclusions : These results demonstrate that Pt-WE has anti-inflammatory and gastroprotective effects. Thus, Pt-WE may be used widely in treatment of not only neurodegenerative diseases but also inflammatory diseases.

• Korean Journal of Pharmacognosy
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• v.48 no.2
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• pp.155-159
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• 2017

Cudrania tricuspidata Bureau (Moraceae) is a traditional oriental medicine that has been widely used as anti-oxidant, anti-inflammatory and immunomodulatory in Korea. This study was performed that the 70% ethanol extract of the roots of C. tricuspidata (CTE) suppressed receptor activator of NF-${\kappa}B$ ligand (RANKL)-induced osteoclastogenesis, actin ring formation in RAW 264.7 cell lines. CTE significantly inhibited the JNK/mitogen-activated protein kinase (MAPK) signaling pathway without affecting ERK and p38 signaling in RANKL-stimulated RAW 264.7 cells. Also, CTE inhibited RANKL-induced expression of c-Fos, an upstream activator of NFATc1. Consequently, CTE suppresses osteoclast differentiation by inhibiting RANKL induced MAPK signaling pathways and disrupts the actin rings in mature osteoclasts. Thus, CTE can be used for the development of osteoporosis treatment drug with a natural material.

• Nutrition Research and Practice
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• v.3 no.1
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• pp.64-71
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• 2009

Amino acids are fundamental nutrients for protein synthesis and cell growth (increase in cell size). Recently, many compelling evidences have shown that the level of amino acids is sensed by extra- or intra-cellular amino acids sensor(s) and regulates protein synthesis/degradation. Mammalian target of rapamycin complex 1 (mTORC1) is placed in a central position in cell growth regulation and dysregulation of mTOR signaling pathway has been implicated in many serious human diseases including cancer, diabetes, and tissue hypertrophy. Although amino acids are the most potent activator of mTORC1, how amino acids activate mTOR signaling pathway is still largely unknown. This is partly because of the diversity of amino acids themselves including structure and metabolism. In this review, current proposed amino acid sensing mechanisms to regulate mTORC1 and the evidences pro/against the proposed models are discussed.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.274-274
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• 1994

본 연구에서는 토끼신장 근위세뇨관 일차배양세포에서 브라디키닌의 생리작용이 phospholipase D (PLD)에 의해 매개되는지를 살펴 보기위해 PLD 효소반응의 특이한 성질인 transphosphatidylation 반응의 생성물인 phosphatidylethanol (PEth) 의 세포내 양을 측정함으로 PLD 효소의 관련성을 규명할 수 있었다. 시간경과에 따른 phosphatidic acid (PA) 및 diacylglycerol (DAG) 의 생성을 살펴본 결과 PA가 DAG보다 먼저 생성되어 최고치 (30초)에 도달하였고 DAG는 1분이후부터 5분까지 서서히 생성되는 양상을 나타내었다. 또한 0.5에서 5％까지의 에탄올 존재하에 PA 및 PE소 생성량을 비교해본 결과 에탄올량이 증가함에 따라 PA는 감소하는 반민 PEth 의 생성은 계속 증가하였다. 한편 브라디키닌 농도 변화 실험에서는 브라디키닌농도가 증가함에 따라 PA 및 PEth 둘다 생성이 증가되었다. 이러한 결과로부터 토끼신장 근위세뇨관 세포막에 존재하는 브라디키닌수용체는 브라디키닌에 의해 activation 시 PLD를 직접적으로 활성화시켜 그들의 작용을 세포내로 전달한다는 사실을 알 수 있었다. 또한 PLD 효소활성의 activator로 수용체효능 제외에 칼슘이온, protein kinase C (PKC) 등이 몇몇 다른 실험에 의해 밝혀져 있고, G protein 역시 PLD 효소 활성을 조절하는 역할이 있음이 알려졌다. calcium ionophore 및 칼슘채널길항제인 verapamil을 이용한 실험에서 우리는 브라디키닌의 PLD 활성화는 칼슘이온에 의존적인 경로 및 비의존적인 경로가 같이 존재함을 알수 있었다. 또한 브라디키닌의 PLD 활성화기전이 PKC 의존적인지를 살펴보기위해 PKC activator(PMA) 및 inhibitor (staurosporine)를 이용한 실험에서 브라디키닌은 신장세포에서 PKC를 통하여 PLD를 활성화시킴으로 신호전달을 하는 것으로 추측되었다. 마지막으로 가수분해안되는 G protein 유도체인 GTPrS 및 G protein 활성물질 NaF, 백일해독소등을 이용한 실험에서 G protein 의 PLD 조절활성을 확인할 수 있었다.

• Animal Bioscience
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• v.37 no.8
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• pp.1377-1386
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• 2024

Objective: Embryonic interferon-tau (IFNT) and progesterone affect expression of interferon-stimulated genes (ISGs), progesterone receptor (PGR) and progesterone-induced blocking factor (PIBF) in the ovine thyroid. Methods: Thyroids of ewes were sampled at day 16 of nonpregnancy, days 13, 16, and 25 of pregnancy, and real-time quantitative polymerase chain reaction assay, western blot and immunohistochemistry were used to detect expression of ISGs, PGR, and PIBF. Results: Free ISG15 protein was undetected, but ISG15 conjugated proteins upregulated at day 16 of pregnancy, and expression levels of ISG15 conjugated proteins, PGR isoform (70 kDa), PIBF, interferon-gamma-inducible protein 10 and myxovirusresistance protein 1 peaked, but expression level of signal transducer and activator of transcription 1 was the lowest at day 16 of pregnancy. In addition, the expression levels of PGR isoform (70 kDa) and signal transducer and activator of transcription 1 (STAT1) decreased, but levels of PGR isoform (43 kDa), 2',5'-oligoadenylate synthetase, IP-10 and MX1 increased at day 25 of pregnancy comparing with day 16 of the estrous cycle. Conclusion: Early pregnancy affects expression of ISGs, PGR, and PIBF in maternal thyroid through IFNT and progesterone, which may regulate thyroid autoimmunity and thyroid hormone secretion in ewes.