• Journal of Applied Biological Chemistry
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• 제44권3호
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• pp.105-112
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• 2001

Insect pests can be controlled through direct application of insecticides. Insect control by residual protectants is relatively inexpensive and has an advantage of destroying all stages of infestations. The efficacy of control is largely determined by the concentration of insecticides to which the pest species is exposed. A reduction in the period of control in the field afforded by a specific level of a protectant indicates that resistance has developed. An increase in the level of protectant is required to maintain control, and the efficacy of currently used insecticides has been severely reduced by insecticide resistance in pest species. Development of resistance to particular insecticide varies with species because insecticide resistance is often correlated with increased levels of certain enzymes, which are cytochrome P450-dependent monooxygenases, glutathione S-transferases and esterases. Some sections of insecticide molecules can be modified by one or more of these primary enzymes. A reduction in the sensitivity of the action site of a xenobiotic also constitutes a mechanism of resistance. Acetylcholinesterase is a major target site for insecticide action, as are axonal sodium ion channels and ${\gamma}$-aminobutyric acid receptors. Development of reduced sensitivity of these target sites to insecticides usually occurs. This review not only may contribute to a better understanding of insecticide resistance, but also illustrates the gaps still present for a full biochemical understanding of the resistance.

• 생약학회지
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• 제34권2호통권133호
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• pp.161-165
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• 2003

Ethanol extract from Thesium chinense Tunczaninov (TCTE) was tested for breast cancer chemopreventive activity by measuring 7,12-dimethylbenz[a]anthracene (DMBA) - induced cytochrome P450 1A1 activity, induction of quinone reductase and glutathione S-transferase, and glutathione level. TCTE significantly inhibited cytochrome P45O 1A1 activity at the concentration of 90 and 150 mg/ml. TCTE induced quinone reductase activity in a dose-dependent manner in a concentration range of 3-150 mg/ml. In addition glutathione S-transferase activity and glutathione level were increased with TCTE in cultured murine hepatoma Hepa1c1c7 cells. These results suggest that TCTE has breast cancer chemopreventive potential by inhibiting cytochrome P45O 1A1 activity, inducing quinone reductase and glutathione S-transferase activities, and increasing GSH level.

• 한국식품영양과학회지
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• 제24권6호
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• pp.859-866
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• 1995

본 연구에서는 액체식이로 알코올을 열량의 35%로 6주간 섭취시킨 흰주의 간조직내 지질과산화물과 glutathione 이용효소계의 활성도 및 cytochrome P-450에 미치는 영향을 살펴보고 아울러 간암의 발암원으로 알려진 2-AAF를 투여하여 이들의 상호효과를 조사한 결과 다음과 같은 결과를 얻었다. 1. 체중, 간무게, 그리고 체중에 대한 간무게의 알코올에 대한 효과는 유의적인 차이를 보여 체중은 알코올에 대한 효과는 유의적인 차이를 보여 체중은 알코올 섭취군이 유의적으로 감소하였고 간무게 및 체중에 대한 간무게는 알코올군의 유의적으로 증가하였다. 2. Microsome의 지질과산화물 함량 및 cytosol의 glutathione peroxidase, glutathione reductase 활성도는 알코올과 2-AAF 투여시 모두 유의적인 차이를 보이지 않았으나, cytosol의 glutathione S-transferase 활성도는 알코올과 2-AAF에 의해서 모두 유의적으로 증가하였고 알코올 섭추와 함께 투여시 GST 활성도가 가장 많이 증가하였다. 3. Microsome의 cytochrome P-450 및 cytochrome b5 함량에 대한 알코올 효과는 cytochrome P-450 함량을 증가시키는 경향이 있고 cytochrome b5는 유의적인 증가를 보여 주었으며 2-AAF 투여 역시 cytochrome P-450의 유의적인 증가를 유도하였다. 따라서 알코올 섭취와 2-AAF 함께 투여 시 cytochrome P-450의 함량이 대조군의 약 2.2배 정도 증가하였으며 cytochrome b5 함량이 1.7배로 높이 증가하였다. 이는 2-AAF가 cytochrome P-450을 유도하여 자신의 대사를 촉진시키며 알코올의 섭취 또한 2-AAF의 hydroxylation을 증가시킬 수 있는 것으로 생각된다. 이상의 결과에서 과량의 알코올을 만성적으로 섭취시 간조직내의 microsome의 MFO system에 영향을 미쳐서 발암물질의 생체 활성화를 촉진시킬 수 있고 또한 GST의 활성도를 증가시키므로 어느 정도 발암과정에 영향을 미치는 것으로 생각된다.

• Journal of Microbiology and Biotechnology
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• 제33권3호
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• pp.299-309
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• 2023

Glutathione peroxidases (Gpx) are a group of antioxidant enzymes that protect cells or tissues against damage from reactive oxygen species (ROS). The Gpx proteins identified in mammals exhibit high catalytic activity toward glutathione (GSH). In contrast, a variety of non-mammalian Gpx proteins from diverse organisms, including fungi, plants, insects, and rodent parasites, show specificity for thioredoxin (TRX) rather than GSH and are designated as TRX-dependent peroxiredoxins. However, the study of the properties of Gpx in the environmental microbiome or isolated bacteria is limited. In this study, we analyzed the Gpx sequences, identified the characteristics of sequences and structures, and found that the environmental microbiome Gpx proteins should be classified as TRX-dependent, Gpx-like peroxiredoxins. This classification is based on the following three items of evidence: i) the conservation of the peroxidatic Cys residue; ii) the existence and conservation of the resolving Cys residue that forms the disulfide bond with the peroxidatic cysteine; and iii) the absence of dimeric and tetrameric interface domains. The conservation/divergence pattern of all known bacterial Gpx-like proteins in public databases shows that they share common characteristics with that from the environmental microbiome and are also TRX-dependent. Moreover, phylogenetic analysis shows that the bacterial Gpx-like proteins exhibit a star-like radiating phylogenetic structure forming a highly diverse genetic pool of TRX-dependent, Gpx-like peroxidases.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권3호
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• pp.155-162
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• 2002

The cyclic amidohydrolase family enzymes, which include allantoinase, dihydroorotase, dihydropyrimidinase and (phenyl)hydantoinase, are metal-dependent hydrolases and play a crucial role in the metabolism of purine and pyrimidine in vivo. Each enzyme has been independently characterized, and thus well documented, but studies on the higher structural traits shared by members of this enzyme family are rare due to the lack of comparative study. Here, we report upon the expression in E. coli cells of maltose-binding protein (MBP)- and glutathione S-transferase (GST)-fused cyclic amidohydrolase family enzymes, facilitating also for both simple purification and high-level expression. Interestingly, the native quaternary structure of each enzyme was maintained even when fused with MBP and GST. We also found that in fusion proteins the favorable biochemical properties of family enzymes such as, their optimal pHs, specific activities and kinetic properties were conserved compared to the native enzymes. In addition, MBP-fused enzymes showed remarkable folding ability in-vitro. Our findings, therefore, suggest that a previously unrecognized trait of this family, namely the ability to functional fusion with some other protein but yet to retain innate properties, is conserved. We described here the structural and evolutionary implications of the properties in this family enzyme.

• Preventive Nutrition and Food Science
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• 제15권4호
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• pp.267-274
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• 2010

We assessed the effect of Se-methylselenocysteine (MSC) treatment, at a dose of 0.75 mg/rat/day for 1 or 2 weeks, on the activities of antioxidant systems in Sprague-Dawley rat tissues. Significant changes in glutathione and antioxidant enzyme activities, with different patterns among tissues, were evidenced. Glutathione content and its reduction state in the liver, lung, and kidney were elevated upon MSC treatment, whereas they were significantly lowered in the spleen. Among the tissues exhibiting glutathione increase, there were different enzymatic responses: $\gamma$-glutamylcysteine ligase activity, the rate-limiting enzyme in the glutathione synthesis pathway, was increased in the liver, whereas the activities of the enzymes associated with glutathione recycling, namely, glutathione peroxidase, glutathione reductase, and glucose 6-phosphate dehydrogenase, were significantly increased in the lung and the kidney. The superoxide dismutase activity was decreased in all tissues upon MSC treatment, whereas catalase activity was increased in all tissues but the liver. Lipid peroxidation level was transiently increased at 1 week in the lung and the kidney, whereas it was persistently increased in the spleen. The increase was not evident in the liver. The results indicate that the MSC treatment results in an increase in the antioxidant capacity of the liver, lung, and kidney principally via an increase in glutathione content and reduction, which appeared to be a result of increased synthesis or recycling of glutathione via tissue-dependent adaptive response to oxidative stress triggered by MSC. The spleen appeared to be very sensitive to oxidative stress, and therefore, the adaptive response could not provide protection against oxidative damage.

• Fisheries and Aquatic Sciences
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• 제19권4호
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• pp.19.1-19.7
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• 2016

A laboratory experiment was conducted to determine hexavalent chromium ($Cr^{6+}$) accumulation in the mullet and investigate $Cr^{6+}$ toxicity using a panel of biomarkers including metallothioneins (MTs), glutathione (GSH), glutathione S-transferase (GST), and superoxide dismutases (SODs) for 4 weeks. $Cr^{6+}$ bioaccumulation in all tissues, except muscle, was consistently time- and dose-dependent. The accumulation of $Cr^{6+}$ for 4-week exposures was in the following order: $kidney{\approx}liver$ > $intestine{\approx}gill$ > spleen > muscle. Compared with the control, $Cr^{6+}$ bioaccumulation was increased in ${\geq}200{\mu}g\;L^{-1}$ groups (P < 0.05). An independent relation was observed between accumulation factors (AFs) and exposure concentration. But AFs increased with exposure time. In the liver and gill, GST and SOD differed from the control at a high $Cr^{6+}$ concentration at 2 and 4 weeks (P < 0.05). This study indicated that the gills were as sensitive as the liver to $Cr^{6+}$ toxicity. However, the latter appeared to influence largely on the organism's adaptive response to $Cr^{6+}$, since $Cr^{6+}$ may elevate GSH and MT levels by enhancing the hepatic uptake of metal in the mullet.

• 생약학회지
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• 제33권4호통권131호
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• pp.376-383
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• 2002

The methanol extracts prepared from ten kinds of culinary herbs were investigated for the cytotoxcic effect againt L1210 cancer cells and the mode of action. The substantial cytotoxic effects were observed in all cases with the most prominent effect demonstrated by lemon verbena extract showing $87{\pm}4.1%$ cytotoxicity with $100{\mu}g/ml$ concentration and 3 days culture period. The cytotoxic effect was found to be dose and culture period dependent. With respect to the mechanism of the cytotoxicity, the augmented generation of $O_2{^-}ion$ and the dramatically escalated activities of antioxidant enzymes such as superoxide dismutase(SOD) and glutathione peroixdase (GPx) with addition of the herb methanol extractw suggested that there would be the involvement of reactive oxygen species (ROS) metabolism in the course of L1210 cancer cell death by the mothanol extract of the edible herbs.

• Preventive Nutrition and Food Science
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• 제8권4호
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• pp.365-371
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• 2003

The potential of seven flavonoid glycosides to induce quinone reductase (QR), an anticarcinogenic marker enzyme, in murine hepatoma cells (hepalc1c7) and its mutant cells (BPRc1) was evaluated. Among test compounds, kaempferol-3-O-glucoside, luteolin-6-c-glucoside, and quercetin-3-O-glucoside (Q-3-G) induced QR in hepalc1c7 cells in a dose-dependent manner. However, in BPRc1 cells lacking arylhydrocarbon receptor nuclear translocator (ARNT), only Q-3-G caused a significant induction of quinone reductase at the concentration range of 0.5 to 8 ug/mL, suggesting that it is a monofunctional inducer. Q-3-G induced not only phase 2 enzymes, including QR and glutathione-S-transferase, but also nitroblue tetrazolium reduction activity in HL-60 cells, a biochemical marker for cell differentiation promoting agents. In conclusion, Q-3-G merits further study to evaluate its cancer chemopreventive potential.

• 대한한의학회지
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• 제17권1호
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• pp.21-36
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• 1996

This study was undertaken to examine the effect of Jwagyuyeum and Woogyuycum, being known to reinforce Kidney-yin and yang, on the activities of endogenous antioxidant enzymes and the production of oxygen free radicals in the liver and kidney tissues, Alterations in enzyme activities were observed after in vivo treatment in rats, Jwagyuyeum and Woogyuyeum caused a significant increase in the activities of superoxide dismutase(SOD) and catajase Jwagyuyeum significantly increased the activity of glutathione peroxidase in both liver and kidney, but the enzyme activity was not significantly altered by Woogyuyeum. Treatment in vitro of Jwagyuyeum and Woogyuyeum decreased the production of oxygen free radicals in a dose-dependent fashion. These results suggest that Jwagyuyeum and Woogyuyeum stimulate the activities of antioxidant enzymes and inhibit directly the production of oxygen free radicals. These effects of both herbs may contribute to prevent the oxygen free radical-induced impairment of cell function.