• 한국식품과학회지
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• 제41권5호
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• pp.592-596
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• 2009

40종류 이상의 식물의 유식물체, 채소 그리고 가공식품의 글루타치온과 그의 산화형 글루타치온(GSSG)함량을 측정하였다. 유식물체를 이용한 실험에서 총글루타치온 함량은, 100 g(생체중)당 $0-120{\mu}mol$의 범위였으며, 같은 과, 종 및 품종에 있어서도 현저한 차이를 나타내었다. 특히, 시판되고 있는 곡물과 채소를 이용한 실험에서는 콩과의 팥과 강낭콩에서 높은 글루타치온 함량을 나타내었다. 콩을 이용한 가공식품(고추장, 된장, 간장 등)에서는 글루타치온 함량이 거의 검출되지 않았다. 식품에 있어서 고농도의 글루타치온은 식품의 높은 부가가치가 되리라 생각된다.

• BMB Reports
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• 제46권3호
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• pp.169-174
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• 2013

The human $B_{12}$ trafficking chaperone hCblC is well conserved in mammals and non-mammalian eukaryotes. However, the C-terminal ~40 amino acids of hCblC vary significantly and are predicted to be deleted by alternative splicing of the encoding gene. In this study, we examined the thermostability of the bovine CblC truncated at the C-terminal variable region (t-bCblC) and its regulation by glutathione. t-bCblC is highly thermolabile ($T_m={\sim}42^{\circ}C$) similar to the full-length protein (f-bCblC). However, t-bCblC is stabilized to a greater extent than f-bCblC by binding of reduced glutathione (GSH) with increased sensitivity to GSH. In addition, binding of oxidized glutathione (GSSG) destabilizes t-bCblC to a greater extent and with increased sensitivity as compared to f-bCblC. These results indicate that t-bCblC is a more sensitive form to be regulated by glutathione than the full-length form of the protein.

• Toxicological Research
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• 제7권2호
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• pp.231-238
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• 1991

The pesticide and carcinogen ethylene dibromide(EDB) is metabolized both by cytosolic GSH S-transferase and by microsomal mixed function oxygenase. Cytochrome P-450 IIE1 appears to be major enzyme to metabolize EDB.EDB is activated to a mutagen by enzymatic conjugation with glutathione (GSH). Such activation is an exception to the general mode of detoxification via GSH S-transferase action. The primary DNA adduct (>95) is S-[2-(N7-guanyl)ethyl] GSH and a minor adduct is S-[2-(N7-guanyl)ethyl]cysteine, which is excreted in the urine and may serve as a biomarker of damage.

• Asian Pacific Journal of Cancer Prevention
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• 제13권12호
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• pp.6403-6407
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• 2012

Detoxifying enzymes are present in most epithelial cells of the human gastrointestinal tract where they protect against xenobiotics which may cause cancer. Induction of examples such as glutathione S-transferase (GST) and its thiol conjugate, glutathione (GSH) as well as NAD(P)H: quinoneoxidoreductase (NQO1) facilitate the excretion of carcinogens and thus preventing colon carcinogenesis. Pterostilbene, an analogue of resveratrol, has demonstrated numerous pharmacological activities linked with chemoprevention. This study was conducted to investigate the potential of pterostilbene as a chemopreventive agent using the HT-29 colon cancer cell line to study the modulation of GST and NQO1 activities as well as the GSH level. Initially, our group, established the optimum dose of 24 hours pterostilbene treatment using MTT assays. Then, effects of pterostilbene ($0-50{\mu}M$) on GST and NQO1 activity and GSH levels were determined using GST, NQO1 and Ellman assays, respectively. MTT assay of pterostilbene ($0-100{\mu}M$) showed no cytotoxicity toward the HT-29 cell line. Treatment increased GST activity in the cell line significantly (p<0.05) at 12.5 and $25.0{\mu}M$. In addition, treatment at $50{\mu}M$ increased the GSH level significantly (p<0.05). Pterostilbene also enhanced NQO1 activity significantly (p<0.05) at $12.5{\mu}M$ and $50{\mu}M$. Hence, pterostilbene is a potential chemopreventive agent capable of modulation of detoxifiying enzyme levels in HT-29 cells.

• 대한의생명과학회지
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• 제6권1호
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• pp.29-36
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• 2000

실험동물에 있어서 간조직의 손상 정도에 미치는 xenobiotics의 투여기간에 의한 영향을 검토할 목적으로 hepatotoxin의 일종인 bromobenzene의 투여 횟수에 의한 간손상 정도와 이의 기전을 구명 한 결과는 다음과 같다. 흰쥐에 1일 간격으로 bromobenzene (400 mg/kg)을 복강으로 1회, 3회 및 6회 투여한 실험군을 대상으로 하여 실시한 실험에서 혈청 alanine aminotransferase (ALT)의 활성 및 체중 당 간 무게는 bromobenzene을 1회 투여 한 1일째에는 대조군과 별다른 변동을 볼 수 없었으나 3회 투여 한 3일째에는 유의하게 증가되었으며, 이후 6일째 6회 투여한 실험군에서는 체중 당 간 무게 및 혈청 ALT활성이 3일째 보다 현저히 감소되어 오히려 대조군과 유사하였다. 이와 같이 투여 횟수의 증가에 따른 간손상의 정도가 투여 횟수와 비례하지 않은 것이 어떠한 기전에 의해서 나타나는지를 구명하기 위해 bromobenzene 대사에 관여하는 간조직 중 aniline hydroxylase 및 glutathione S-transferase 활성과 glutathione (GSH) 함량을 측정한 결과, 이들 대사효소 및 GSH 이용률이 bromobenzene 6회 투여군에서 1회 및 3회 투여군 보다 높게 나타났다. 이상 실험 결과를 종합해 볼 때 어떤 독성물질이 생체에 계속 폭로 시 어느 시점에서 중독현상이 경감되는 것은 이 독성물질의 대사율을 증가시켜 해독하려는 생리적응현상이 일어 날 수 있다는 가설을 제시할 수 있다.

• 한국가축번식학회지
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• 제21권4호
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• pp.335-343
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• 1997

The effect of thiol compounds on development and intracellular glutathione(GSH) concentrations of bovine embryos produced by in vitro maturation and in vitro fertilization(IVM/IVF) was examined in CRlaa medium with or without $\beta$-mercaptoethanol(0, 10, 25 and 50$\mu$MME) and cysteamine(0, 25, 50 and 75 $\mu$M). Numbers of cells comprising blastocysts were also counted using double fluorescence stain and the total glutathione levels(oxidized and reduced form) of morula and blastocyst embryos were than measured by an enzymatic method. Following routine IVM/IVF procedures oocytes and zygotes were cultured for 40 to 44h in CRlaa medium. Then 2 to 8-cell embyos had cumulus cell removed and were allotted randomly to the experimental medium. In Experiment 1, the proportion of embryos developing to and beyond morulae stages in 0, 10, 25 and 50 $\mu$M $\beta$-ME was 42.9%, 50.0%, 53.7% and 65.6%, respectively. Fifty $\mu$M $\beta$-ME group was significantly higher than those of any other groups (P<0.05). In Experiment 2, the percentages of embryos developed beyond morulae stages in 0, 25, 50 and 75 $\mu$M cysteamine was 42.9%, 40.4%, 60.0% and 59.2%, respectively. Fifty and 75$\mu$M cysteamine groups were significantly higher than in 0 and 25 $\mu$M cysteamine groups, but all of culture medium containing cysteamine(52.6%) was not significantly difference in control group(42.9%). In Experiment 3, the intracellular GSH concentrations of morulae and blastocyst embryos in 0 and 50 $\mu$M $\beta$-ME was 42.4 pM and 44.9 pM, 49.5 pM and 67.8 pM, respectively. Morulae embryos were not difference, but blastocyst embryos were significantly difference between treatments(P<0.05). In Experiment 4, the intracellular GSH concentrations of morulae in CRlaa with or without cysteamine were 39.8 pM and 45.6 pM, and blastocysts were 59.3 pM and 66.8 pM, respectively. Cell numbers of blastocysts were similar to in all experimental groups. These experiments indicate that thiol compounds can increase the proportion of embryos that developing to and beyond morulae stage and the intracellular GSH concentrations.

• 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.

• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 2002년도 제9회 학술 발표회 프로그램과 논문초록
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• pp.48-48
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• 2002

Glutathione (GSH) is most prevalent reducing thiols in eukaryotic cells and known that participates in many cellular processes. It was found that total amount of glutathione and the ratio of reduced to oxidized glutathione during development of Dictyostelium discoideum increase at the initial stage of the aggregation of amoeba.(omitted)

• Toxicological Research
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• 제7권2호
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• pp.141-149
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• 1991

The treatment with 5ng/ml of mercuric chloride caused time-dependent decreases, and in the activities of GSH S-transferase and GSH-peroxidase, and in the concentration of GSH in CHO cells. Three hours after treatment of $Hg^{2+}$, the activity of GSH S-transferase was decreased to almost half value of control group and the activity of GSH-peroxidase was reduced significantly at 6 hr after treatment. The concentration of GSH was decreased 2 hr after treatment of $Hg^{2+}$ and was decreased to nearly half value of control group 3 hr after treatment.

• Bulletin of the Korean Chemical Society
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• 제31권9호
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• pp.2497-2502
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• 2010

Arg13 is a conserved active-site residue in all known Pi class glutathione S-transferases (GSTs) and in most Alpha class GSTs. To evaluate its contribution to substrate binding and catalysis of this residue, three mutants (R13A, R13K, and R13L) were expressed in Escherichia coli and purified by GSH affinity chromatography. The substitutions of Arg13 significantly affected GSH-conjugation activity, while scarcely affecting glutathione peroxidase or steroid isomerase activities. Mutation of Arg13 into Ala largely reduced the GSH-conjugation activity by approximately 85 - 95%, whereas substitutions by Lys and Leu barely affected activity. These results suggest that, in the GSH-conjugation activity of hGST P1-1, the contribution of Arg13 toward catalytic activity is highly dependent on substrate specificities and the size of the side chain at position 13. From the kinetic parameters, introduction of larger side chains at position 13 results in stronger affinity (Leu > Lys, Arg > Ala) towards GSH. The substitutions of Arg13 with alanine and leucine significantly affected $k_{cat}$, whereas substitution with Lys was similar to that of the wild type, indicating the significance of a positively charged residue at position 13. From the plots of log ($k_{cat}/{K_m}^{CDNB}$) against pH, the $pK_a$ values of the thiol group of GSH bound in R13A, R13K, and R13L were estimated to be 1.8, 1.4, and 1.8 pK units higher than the $pK_a$ value of the wild-type enzyme, demonstrating the contribution of the Arg13 guanidinium group to the electrostatic field in the active site. From these results, we suggest that contribution of Arg13 in substrate binding is highly dependent on the nature of the electrophilic substrates, while in the catalytic mechanism, it stabilizes the GSH thiolate through hydrogen bonding.