• The Korean Journal of Physiology and Pharmacology
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• 제5권3호
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• pp.271-278
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• 2001

Oxidative stress and methylglyoxal (MG), a reactive dicarbonyl metabolites produced by enzymatic and non-enzymatic reaction of normal metabolism, induced aldose reductase (AR) expression in rat aortic smooth muscle cells (SMC). AR expression was induced in a time-dependent manner and reached at a maximum of 4.5-fold in 12 h of MG treatment. This effect of MG was completely abolished by cyclohemide and actinomycin D treatment suggesting AR was synthesized by de novo pathway. Pretreatment of the SMC with N-acetyl-L-cysteine significantly down-regulated the MG-induced AR mRNA. Furthermore, DL-Buthionine-(S,R)-sulfoximine, a reagent which depletes intracellular glutathione levels, increased the levels of MG-induced AR mRNA. These results indicated that MG induces AR mRNA by increasing the intracellular peroxide levels. Aminoguanidine, a scanvenger of dicarbonyl, significantly down-regulated the MG-induced AR mRNA. In addition, the inhibition of AR activities with statil, an AR inhibitor, enhanced the cytotoxic effect of MG on SMC under normal glucose, suggesting a protective role of AR against MG-induced cell damages. These results imply that the induction of AR by MG may contribute to an important cellular detoxification of reactive aldehyde compounds generated under oxidative stress in extrahepatic tissues.

• 약학회지
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• 제39권4호
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• pp.450-460
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• 1995

The acute toxicity of fthalide in rat was studied in vivo by the observations of the changes in hematogram, serological parameters, content of cytochrome p-450, activities of NADPH-cytochrom c reductase, glucose-6-phosphatase, and the contents of cholinesterase and carboxylesterase in liver. Fthabde is a practically non-toxic substance(LD50 is 3.86g/kg), but rats were intoxicated with fthabde at a oral dose of 100 mg/kg for 12 days. WBC were significantly decreased and activities of ALT and LDH, on the cotrary, the content of glucose in serum were slightly increased. Cytochrome p-450 and lipid peroxide in liver were significantly increased in the fthalide-intoxicated rats. The longer administration of fthalide showed further increase of carboxylesterase activity in liver and serum, but decrease of activities of glucose-6-phosphatase and cholinesterase in liver and serum. These results show that fthatide can induce the hepatocellular injury and neurotoxicity.

• The Korean Journal of Ecology
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• 제27권2호
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• pp.107-114
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• 2004

Tomato (Lycopersicon esculentum) seedlings exposed to various concentrations of $CdC1_2$ (0∼100 $\mu$M) in the nutrient solution for up to 9 days were analyzed with the seedling growth, $H_2O_2$ production, glutathione levels and activity changes of enzymes related to $H_2O_2$ removal. The growth of seedlings was inhibited with over 50 $\mu$M Cd, whereas the levels of $H_2O_2$ and glutathione were enhanced with Cd exposure level and time. Meanwhile, Cd exposure increased the activities of catalase (CAT) and glutathione reductase (GR) but decreased the activities of dehydroascorbate acid reductase (DHAR) and ascorbate peroxidase (APX) in both leaves and roots. These results suggest that the altered activities of antioxidant enzymes particularly involved in the $H_2O_2$ removal and the subsequent $H_2O$$_2$ accumulation could induce the Cd-induced phytotoxicity.

• 한국식품영양과학회지
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• 제29권3호
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• pp.448-452
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• 2000

실험동물에서 곰피로부터 분리한 phlorglucinol은 acetaminophen의 투여로 현저히 증가된 간조직에 있어서 지질과선화의 함량을 억제하였다. Acetaminophen 투여에 따른 간 cytochrome P-450, aminopyrine N-deme-thylase 및 aniline hydroxylase 활성변동은 관찰할 수 없었다. 곰피 성분 투여군은 glutathione S-transferase의 활성에서는 대조군의 수준에는 미치지 않으나 효소의 활성이 acetaminophen 단독 투여군보다 현저히 증가되었다. 그리고 간조직중 glutathione의 함량은 phlorglucionl을 전처리군에서 acetaminophen 단독 투여군보다 증가되었다. Glutathione reductase 활성에서는 acetaminophen 투여군은 대조군보다 활성이 감소되었으며, 성분으로 전처리한 군은 acetaminophen 단독 투여군보다 증가 되었다. 따라서 곰피에서 분리한 페놀성화합물인 phloroglucinol은 acetaminophen 투여로 증가되던 지질과 산화함량을 감소시키며, acetaminophen 대사효소활성에서는 glutathione S-transferase의 활성이 증가되어 acetaminophen 의 대사를 촉진시키는 것으로 추정된다.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.1
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• pp.261.1-261.1
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• 2003

The EtOAc and CH$_2$Cl$_2$ soluble fractions from the fruit body of Ganoderma applanatum showed strong aldose reductase inhibitory activity. Nine compounds were isolated from both fractions. They were identified by spectral data as D-mannitol (1), 2-methoxyfatty acid (2), cerebrosides [(2S,3R,4E,8E)-1-O-${\beta}$-D-glucopyranosyl-3-hydroxy-2-[(R)-2'-hydroxypalmitoyl]amino-9-methyl-4,8-octadecadiene] (3), daucosterol (4), 2,5-dihydroxybenzoic acid (5), protocatechualdehyde (6), 5-dihydroergosterol (7), ergosterol peroxide (8), and cerevisterol (9). (omitted)

• Journal of Microbiology
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• 제41권3호
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• pp.248-251
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• 2003

Glutathione (GSH) is an important factor in determining tolerance against oxidative stress in living organisms. It is synthesized in two sequential reactions catalyzed by ${\gamma}$-glutamylcysteine synthetase (GCS) and glutathione synthetase (GS) in the presence of ATP. In this work, the effects of three different oxidative stresses were examined on GSH content and GSH-related enzyme activities in the fission yeast Schizosaccharomyces pombe. GSH content in S. pombe was significantly enhanced by treatment with hydrogen peroxide, ${\beta}$-naphthoflavone (BNF) and tert-butylhydroquinone (BHQ). Simultaneously, they greatly induced GCS and GS activity. However, they did not have any effects on glutathione reductase activity. These results suggest that GCS and GS activities in S. pombe are up-regulated by oxidative stress.

• 원예과학기술지
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• 제33권3호
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• pp.383-389
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• 2015

Chitooligosaccharide (COS), as antioxidant, extensively applied to food and juice preservation. In the present study, influences of COS on vase life and ornamental value of cut roses were investigated. Results showed that vase life of cut roses treated by COS was longer 6.4 days than one of control and ornamental character of cut roses was improved effectively by COS. The increase of vase life and ornamental value were chiefly governed by that COS improved water absorption capacity of cut roses. Besides that, COS decreased the contents of superoxide anion and hydrogen peroxide and lowered the levels of malondialdehyde in turn during the senescence process of cut roses. That was because that COS not only enhanced activities of antioxidant enzymes glutathione reductase, but also improved reduced glutathione contents in petals of cut rose. Therefore, COS could be used in commercial preservatives to improve the longevity of cut roses.

• Journal of Microbiology and Biotechnology
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• 제16권3호
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• pp.386-390
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• 2006

A green fluorescent protein-based Pseudomonas putida reporter was successfully constructed and shown to be capable of detecting oxidative stress. In this whole-cell reporter, the promoter of the paraquat-inducible ferredoxin-$NADP^+$ reductase (fpr) was fused to a promoterless gfp gene on a broad-host-range promoter probe vector. Pseudomonas putida KT2440 harboring this reporter plasmid exhibited an increased level of gfp expression in the presence of redox-cycling agents (paraquat and menadione), hydrogen peroxide, and potential environmental pollutant chemicals such as toluene, paint thinner, gasoline, and diesel. Induction of fpr in the presence of these chemicals was confirmed using Northern blot analysis.

• International Journal of Vascular Biomedical Engineering
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• 제2권2호
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• pp.1-9
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• 2004

The history of studies in biology regarding reactive oxygen species (ROS) is approximately 40 years. During the initial 30 years, it appeared that these studies were mainly focused on the toxicity of ROS. However, recent studies have identified another action regarding oxidative signaling, other than toxicity of ROS. Basically, it is suggested that ROS are reactive, and degenerate to biomolecules such as DNA and proteins, leading to deterioration of cellular functions as an oxidative stress. On the other hand, recent studies have shown that ROS act as oxidative signaling in cells, resulting in various gene expressions. Recently ROS emerged as critical signaling molecules in cardiovascular research. Several studies over the past decade have shown that physiological effects of vasoactive factors are mediated by these reactive species and, conversely, that altered redox mechanisms are implicated in the occurrence of metabolic and cardiovascular diseases ROS is a collective term often used by scientist to include not only the oxygen radicals($O2^{-{\cdot}},\;{^{\cdot}}OH$), but also some non-radical derivatives of oxygen. These include hydrogen peroxide, hypochlorous acid (HOCl) and ozone (O3). The superoxide anion ($O2^{-{\cdot}}$) is formed by the univalent reduction of triplet-state molecular oxygen ($^3O_2$). Superoxide dismutase (SOD)s convert superoxide enzymically into hydrogen peroxide. In biological tissues superoxide can also be converted nonenzymically into the nonradical species hydrogen peroxide and singlet oxygen ($^1O_2$). In the presence of reduced transition metals (e.g., ferrous or cuprous ions), hydrogen peroxide can be converted into the highly reactive hydroxyl radical (${^{\cdot}}OH$). Alternatively, hydrogen peroxide may be converted into water by the enzymes catalase or glutathione peroxidase. In the glutathione peroxidase reaction glutathione is oxidized to glutathione disulfide, which can be converted back to glutathione by glutathione reductase in an NADPH-consuming process.

• Journal of Plant Biotechnology
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• 제34권3호
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• pp.173-180
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• 2007

The full-length cDNA of LeAPR1 encoded a protein of 461 amino acid residues, which contained homology with phosphoadenosine phosphosulphate reductase (PAPS reductase) in N-terminal and an adenylylsulfate reductase in N-term and C-terminal. Analysis of the deduced amino acid sequence of LeAPR1 revealed that it shares high sequence identity with potato StAPR (96% identity)(Gene bank accession no. CDC44841). We found that multiple copies of LeAPR1 gene are present in the tomato genome through southern blot using genomic DNA was digested with 3 different restriction enzymes. The expression of LeAPR1 was also examined in various organs and its expression was also detected at high levels in roots and stems. Only high amounts of LeAPR1 transcripts were detected at high transcripts in the leaves at time 0, and then reduced as the plant stressed by the NaCl and abscisic acid (ABA). After 24h treatment of NaCl and ABA were showed increasing patterns of LeAPR1 gene. Time course of LeAPR1 gene expression was examined under oxidative stresses from metyl viologen (MV) and hydrogen peroxide ($H_2O_2$). In the presence of 10 mM $H_2O_2$ and $50\;{\mu}M$ MV, the levels of LeAPR1 transcript in leaves decreased after 1 h, and then increased strongly, peaked at 24 h. Our results indicated that LeAPR1 may play a role function of circadian regulation involved in abiotic stresses signaling pathways.