• Journal of Plant Biotechnology
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• 제38권1호
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• pp.22-29
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• 2011

비생물학적 스트레스로 $H_2O_2$를 이용하여 산화적 스트레스와 고염분 스트레스를 처리한 후 ROS의 생성을 확인한 결과 스트레스 처리 후 30분에 일시적으로 1차 peak를 형성하였다가 거의 basal level까지 감소하고 다시 증가하여 3시간에 매우 다량의 2차 peak를 형성한 후 거의 basal level로 다시 낮아지는 biphasic 양상을 나타내게 된다. 따라서 ROS의 생성은 초기 30분 내에 일시적으로 발생한 Phase I의 ROS와 Phase II의 좀 더 장기적으로 다량의 고농도로 발생된 ROS의 생리적 역할이 다를 것으로 여겨진다. 본 논문에서는 스트레스 처리 시 생성되는 ROS를 확인한 후 ROS 생성 유전자인 RbohD와 RbohF 유전자 발현이 억제된 RbohD-AS, RbohF-AS 형질전환 식물체를 이용하여 실험을 수행하였다. 스트레스에 의해 생성되는 ROS의 생성을 억제시킴으로써 스트레스에 대한 ethylene 생성이 더 적은 것으로 나타났다. 또한, 이들 형질전환 식물체에서 ethylene 생성과 $H_2O_2$ 억제 효과를 확인하였으며 고염분 등의 스트레스에 대한 저항성은 ROS와 ethylene의 생성이 저하되어 나타난 것으로 판단된다. 산화적 스트레스와 고염분 스트레스에서 후기 ethylene이 다량으로 생성되는 시기, 즉 세포손상이 초래되는 후기에서 DNA fragmentation 분석을 통해서 ROS와 ethylene의 생성이 높은 식물체일수록 PCD가 높게 나타난 것으로 여겨지며, 이 과정에서 작용하는 유전자는 RbohD와 RbohF인 것으로 보이며, RbohD가 더 효과적으로 작용하는 것으로 생각된다. 따라서 스트레스에 반응하는 신호전달과정에서 초기에 ROS가 생성이 되고 후기에 ethylene이 다량으로 생성되어 결국 세포죽음에 이르게 하는 상호 synergism을 일으켜 반응을 나타내며, 이러한 반응 과정에서 RbohD와 RbohF 유전자 발현의 억제가 스트레스에 대한 식물체의 저항성을 높이는 것으로 사료된다.

• Environmental Analysis Health and Toxicology
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• 제15권3호
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• pp.69-80
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• 2000

ADP-rubosylation may be involved in the process of macrophage activation. Nitric oxide (NO) has emerged as an important intracellular and interacellular regulatory molecule with function as diverse as vasodilation, neural communication or host defense. NO is derived from the oxidation of the terminal guanidino nitrogen atom of L-arginine by the NADPH -dependent enzyme, nitric oxide synthase (NOS) which is one of the three different isomers in mammalian tissues. Since NO can exert protective or regulatory functions in the cell at a low concentration while toxic effects at higher concentrations, its role may be tightly regulated in the cell. Therefore, this paper was focused on signal transduction pathway of NO synthesis, role of endogenous TGF-$\beta$ in NO production. effect of NO on superoxide formation. Costimulation of murine peritoneal macrophages with interferon-gamma (IFN-γ) and phorbol 12-myristate 13-acetate (PMA) increased both NO secretion and mRNA expression of inducible nitric oxide synthase (iNOS) when PMA abolished costimulation. Pretreatmnet of the cells with PMA abolished costimuation effects due to the depletion of protein kinase C (PKC) activities . The involvement of PKC in NO secretion could be further confirmed by PKC inhibitor, stauroprine, and phorbol ester derivative, phorbol 12,13-didecanoate. Addition of actinomycine D in IFN-γ plus PMA stimulated cells inhibited both NO secretion and mRNA expression of iNOS indication that PMA stabilizes mRNA of iNOS . Exogenous TGF-$\beta$ reduced NO secretion in IFN -γ stimulated murine macrophages. However addition of antisense oligodeoxynucleotide (ODN) to TGF-$\beta$ to this system recovered the ability of NO production and inhibited mRNA expression of TGF-$\beta$. ACAS interactive laser cytometry analysis showed that transportation of FITC -labeled antisense ODN complementary to TGF-$\beta$ mRNA could be observed within 5 min and reached maximal intensity in 30 min in the murine macrophage cells. NO released by activated macrophages inhibits superoxide formation in the same cells . This inhibition nay be related on NO-induced auto -adenosine diphosphate (ADP) -ribosylation . In addition, ADP-ribosylation may be involved in the process of macrophage activation .

• The Korean Journal of Physiology and Pharmacology
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• 제16권1호
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• pp.17-24
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• 2012

The hypothalamus-pituitary-adrenocortex (HPA) axis is the central mediator of the stress response. The supramammillary (SuM) region is relatively unique among the hypothalamic structures in that it sends a large, direct projection to the hippocampal formation. It has been shown that mild stress could activate the SuM cells that project to the hippocampus. However, the role of these cell populations in modulating the stress response is not known. The present study examined the effect of stress on different populations of SuM cells that project to the hippocampus by injecting the fluorescent retrograde tracer, fluorogold (FG), into the hippocampus and utilizing the immunohistochemistry of choline acetyltransferase (ChAT), corticotrophin releasing factor (CRF), serotonin (5-HT), glutamate decarboxylase (GAD), tyrosine hydroxylase (TH) and NADPH-d reactivity. Immobilization (IMO) stress (2 hr) produced an increase in the expression of ChAT- immunoreactivity, and tended to increase in CRF, 5-HT, GAD, TH-immunoreactivity and nitric oxide (NO)-reactivity in the SuM cells. Fifty-three percent of 5-HT, 31% of ChAT and 56% of CRF cells were double stained with retrograde cells from the hippocampus. By contrast, a few retrogradely labeled cells projecting to the hippocampus were immunoreactive for dopamine, ${\gamma}$-aminobutyric acid (GABA) and NO. These results suggest that the SuM region contains distinct cell populations that differentially respond to stress. In addition, the findings suggest that serotonergic, cholinergic and corticotropin releasing cells projecting to the hippocampus within the SuM nucleus may play an important role in modulating stress-related behaviors.

• 한방재활의학과학회지
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• 제23권3호
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• pp.55-68
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• 2013

Objectives This study was to investigate the effects of Yuhyangjeongtong-san on the carrageenin-induced acute inflammation and adjuvant-induced arthritis in rats. Methods Acute inflammation was induced by injection of 2% carrageenin 0.15 ml into right hind foot of rats. Control group was carrageenin injected and taken distilled water, treated group was carrageenin injected and taken Yuhyangjeongtong-san by orally once. 2 hours after injection, plantar temperature and paw volume were measured. 3 hours after, counts of white blood cell (WBC) were performed. Arthritis was induced by injection of complete freund's adjuvant (CFA) into base of tail. Control group was CFA injected and taken distilled water, treated group was CFA injected and taken Yuhyangjeongtong-san by orally for 10 days. 0,5,10 day, body weight, thickness of ankle joint and paw edema were measured. 10 day, counts of WBC, $interleukin-1{\beta}$ ($IL-1{\beta}$) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$) level were analysed. Histochemical study of NADPH-d and immunohistochemical study of c-fos were performed. Results In the carrageenin-induced acute inflammation, neutrophils of treated group were significantly decreased compared with control group. In the adjuvant-induced arthritis, paw edema, total counts of WBC and TNF-${\alpha}$ level in paw exudates were significantly decreased compared with control group, and the number of c-fos positive neurons of treated group was significantly decreased compared with control group. Conclusions On the basis of these results, we concluded that Yuhyangjeongtong-san have anti-arthritic and anti-inflammatory effects.

• Korean Journal of Acupuncture
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• 제23권1호
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• pp.87-94
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• 2006

목적 :본 연구는 collagenase로 유도된 흰쥐의 골관절염 모델에서 진범약침자극이 흰쥐 dorsolateral periaqueductal gray (DL-PAG)에서 NOS 및 nNOS 발현에 미치는 영향을 관찰하였다. 방법 : 흰쥐의 관절강내로 collagenase 용액을 주사하여 골관절염 모델을 만들고 정상군, 대조군 및 진범약침군으로 실험군을 분류한 후, nNOS(neuronal NOS)와 NOS에 대하여 미치는 영향을 nNOS immunohistochemistry와 nicotinamide adenine dinucleotide phosphate-diaphorase(NADPH-d) 검사법을 통하여 조사하였다. 결과 : 골관절염이 유발된 흰쥐의 DL-PAG 영역에서 nNOS와 NOS의 발현억제가 관찰되었으며, 진범약침군이 collagenase로 유도된 골관절염에서 감소된 nNOS와 NOS의 발현이 증가되었다. 결론 : 본 연구를 통하여 진범약침자극은 골관절염이 유발된 흰쥐의 DL-PAG에서의 nNOS와 NOS의발현에 영향을 미친다는 결과를 얻을 수 있었다.

• Korean Journal of Acupuncture
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• 제22권4호
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• pp.109-116
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• 2005

목적 : 골관절염은 진통을 수반하는 퇴행성 관절질환이며, 장애를 일으키는 주요한 원인이 된다. 또한 노인들에 있어서 골관절염은 매우 흔한 질환이라 할 수 있다. Nitric oxide(NO)는 Nitric Oxide Synthase(NOS)에 의하여 칼슘의존성통로를 통하여 L-arginine 으로부터 합성되어지며, NO는 중추신경계에 있어서 중요한 세포사이의 전달자이다. 방법 :본 연구에서는 위령선 으로부터 추출한 액이 콜라겐으로 유도된 관절염에 걸린 쥐의 dorsolateral periaqueductal gray(DL-PAG) 영역에서 nNOS(neuronal NOS)와 NOS에 대하여 미치는 영향 을 nNOS immunohistochemistry와 nicotinamide adenine dinucleotide phosphate-diaphorase(NADPH-d) 검사법을 통하여 조사하였다. 결과 : 골관절염이 유발된 흰쥐의 DL-PAG 영역에서 nNOS와 NOS의 발현억제가 관찰되었으며, 위령선이 콜라겐으로 유도된 골관절염에서 감소된 nNOS와 NOS의 발현이 증가되었다. 결론 : 본 연구를 통하여 위령선은 골관절염이 유발된 흰쥐의 DL-PAG에서의 nNOS와 NOS의 발현에 영향을 미친다는 결과를 얻을 수 있었다.

• 한국식품과학회지
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• 제33권1호
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• pp.122-127
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• 2001

잔나비버섯 자실체로부터 열수추출하여 얻어진 고분자 및 저분자 분획의 이화학적 특성 및 생리활성 대하여 검토하였다. 고분자와 저분자 분획은 당과 단백질 및 소량의 hexosamine을 함유하고 있었다. 구성 당은 주로 glucose, galactose, mannose와 소량의 xylose, fructose, ribose 및 arabinose 등으로 구성되었으며, 아미노산의 경우는 당과 단백질의 결합력에 관여하고 있는 Ser과 Thr를 다량 함유하고 있는 것으로 조사되었다. 고분자 분획의 분자량은 10 kD 부근에서 주를 이루고 있는 것으로 나타났다. 항보체활성은 고분자 분획에서 높았으며, 항체생성능은 대조군에 비해 약간 증가하는 양상을 나타내었다. 탐식능, NO 및 $TNF-{\alpha}$ 생성능은 서로 상관성이 있는 것으로 조사되었다. 효소적 및 비효소적 지질과산화 유발에 대한 영향은 고분자 및 저분자 분획에서 모두 억제능을 나타내었다. 이와 같이 잔나비버섯 자실체로부터 추출한 고분자 및 저분자 분획은 면역활성 및 지질 과산화 억제효과 있는 것으로 조사되었다.

• 혜화의학회지
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• 제8권1호
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• pp.625-641
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• 1999

Aging occurs as a part of maturation as the time progresses which manifests in the human body causing morphological and functional degeneration, eventually leading to death. This experimental study was conducted to investigate a herbal formula to fortify the heart with easy clinical applications. Sungshimsan was chosen to study its effects in heart lipid peroxide and metabolic enzyme system in senescence induced rats. After pre-treatment of Sungshimsan for 2 weeks at the dosage of A (100mg/kg), B (250mg/kg), C (350mg/kg), and D (500mg/kg), a lipid peroxide and metabolic enzyme system changes of the heart were meaured in 32 weeks old rats. The following results were obtained in this study: 1. The contents of lipid peroxide was significantly reduced in the experimental groups treated with greater than 2 weeks at 250mg/kg. 2. The enzymatic activity of cytochrome P-450, cytochrome b5, and NADPH-cytochrome P450 reductase were significantly decreased in the 250mg/kg, 350mg/kg, and 500mg/kg experimental groups. 3. The activity of glutathione and glutathione S-transferase were significantly increased in the 250mg/kg, 350mg/kg, and 500mg/kg experimental groups. 4. The activity of glutathione reductase and glutathione peroxidase were not influenced compared to the control group. 5. The activity of ${\gamma}$-glutamylcystein synthetase was significantly increased in the 250mg/kg, 350mg/kg, and 500mg/kg experimental groups. 6. The activity of enzymes detoxificatioon superoxide dismutase and catalase were not influenced compared to the control group. Summarizing above results suggest that the Sungshimsan has profound effects in the heart lipid peroxide, free radicals, and delaying the heart aging process. Further clinical researches and application can be anticipated on the topic of senility and gerontology.

• The Korean Journal of Physiology and Pharmacology
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• 제25권2호
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• pp.159-166
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• 2021

Nicotinamide adenine dinucleotide phosphate oxidases (NOXs) are the major enzymatic source of reactive oxygen species (ROS). NOX2 and NOX4 are expressed in the heart but its role in hypoxia-induced atrial natriuretic peptide (ANP) secretion is unclear. This study investigated the effect of NOX on ANP secretion induced by hypoxia in isolated beating rat atria. The results showed that hypoxia significantly upregulated NOX4 but not NOX2 expression, which was completely abolished by endothelin-1 (ET-1) type A and B receptor antagonists BQ123 (0.3 μM) and BQ788 (0.3 μM). ET-1-upregulated NOX4 expression was also blocked by antagonists of secreted phospholipase A2 (sPLA2; varespladib, 5.0 μM) and cytosolic PLA2 (cPLA2; CAY10650, 120.0 nM), and ET-1-induced cPLA2 expression was inhibited by varespladib under normoxia. Moreover, hypoxia-increased ANP secretion was evidently attenuated by the NOX4 antagonist GLX351322 (35.0 μM) and inhibitor of ROS N-Acetyl-D-cysteine (NAC, 15.0 mM), and hypoxia-increased production of ROS was blocked by GLX351322. In addition, hypoxia markedly upregulated Src expression, which was blocked by ET receptors, NOX4, and ROS antagonists. ET-1-increased Src expression was also inhibited by NAC under normoxia. Furthermore, hypoxia-activated extracellular signal-regulated kinase 1/2 (ERK1/2) and protein kinase B (Akt) were completely abolished by Src inhibitor 1 (1.0 μM), and hypoxia-increased GATA4 was inhibited by the ERK1/2 and Akt antagonists PD98059 (10.0 μM) and LY294002 (10.0 μM), respectively. However, hypoxia-induced ANP secretion was substantially inhibited by Src inhibitor. These results indicate that NOX4/Src modulated by ET-1 regulates ANP secretion by activating ERK1/2 and Akt/GATA4 signaling in isolated beating rat hypoxic atria.

• 한국미생물생명공학회:학술대회논문집
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• 한국미생물생명공학회 2002년도 학술발표대회
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• pp.18-25
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• 2002

The pikromycin biosynthetic system in Streptomyces venezuleae is unique for its ability to produce two groups of antibiotics that include the 12-membered ring macrolides methymycin and neomethymycin, and the 14-membered ring macrolides narbomycin and pikromycin. The metabolic pathway also contains two post polyketide-modification enzymes, a glycosyltransferase and P450 hydroxylase that have unusually broad substrate specificities. In order to explore further the substrate flexibility of these enzymes a series of hybrid polyketide synthases were constructed and their metabolic products characterized. The plasmid-based replacement of the multifunctional protein subunits of the pikromycin PKS in S. venezuelae by the corresponding subunits from heterologous modular PKSs resulted in recombinant strains that produce both 12- and 14-membered ring macrolactones with predicted structural alterations. In all cases, novel macrolactones were produced and further modified by the DesVII glycosyltransferase and PikC hydroxylase leading to biologically active macrolide structures. These results demonstrate that hybrid PKSs in S. venezuelae can produce a multiplicity of new macrolactones that are modified further by the highly flexible DesVII glycosyltransferase and PikC hydroxylase tailoring enzymes. This work demonstrates the unique capacity of the S. venezuelae pikromycin pathway to expand the toolbox of combinatorial biosynthesis and to accelerate the creation of novel biologically active natural products. The polyketide backbone of rifamycin B is assembled through successive condensation and ${\beta}$-carbonyl processing of the extender units by the modular rifamycin PKS. The eighth module, in the RifD protein, contains nonfunctional DH domain and functional KR domain, which specify the reduction of the ${\beta}$-carbonyl group resulting in the C-21 bydroxyl of rifamycin B. A four amino acid substitution and one amino acid deletion were introduced in the putative NADPH binding motif in the proposed KR domain encoded by rifD. This strategy of mutation was based on the amino acid sequences of the corresponding motif of the KR domain of module 3 in the RifA protein, which is believed dysfunctional, so as to introduce a minimum alteration and retain the reading frame intact, yet ensure loss of function. The resulting strain produces linear polyketides, from tetraketide to octaketide, which are also produced by a rifD disrupted mutant as a consequence of premature termination of polyketide assembly. Much of the structural diversity within the polyketide superfamily of natural products is due to the ability of PKSs to vary the reduction level of every other alternate carbon atom in the backbone. Thus, the ability to introduce heterologous reductive segments such as ketoreductase (KR), dehydratase (DH), and enoylreductase (ER) into modules that naturally lack these activities would increase the power of the combinatorial biosynthetic toolbox. The dehydratase domain of module 7 of the rifamycin PKS, which is predicted to be nonfunctional in view of the sequence of the apparent active site, was replaced with its functional homolog from module 7 of rapamycin-producing polyketide synthase. The resulting mutant strain behaved like a rifC disrupted mutant, i.e., it accumulated the heptaketide intermediate and its precursors. This result points out a major difficulty we have encountered with all the Amycolatopsis mediterranei strain containing hybrid polyketide synthases: all the engineered strains prepared so far accumulate a plethora of products derived from the polyketide chain assembly intermediates as major products instead of just analogs of rifamycin B or its ansamycin precursors.