• 제목/요약/키워드: Glutathione-S-transferase

검색결과 854건 처리시간 0.034초

Monascus pilosus 발효 뽕잎차가 고지방 식이 마우스의 체중과 간 조직 항산화계 효소 활성에 미치는 영향 (Effects of Mulberry Leaf Tea Fermented by Monascus pilosus on Body Weight and Hepatic Antioxidant Enzyme Activities in Mouse Fed High-Fat Diet)

  • 이상일;이예경;이인애;최종근;김순동;서주원
    • 한국식품영양학회지
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    • 제26권1호
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    • pp.66-77
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    • 2013
  • 본 연구에서는 뽕잎차와 Monascus pilosus로 발효시킨 뽕잎차가 ICR mouse의 체중과 간 조직 항산화계 효소류의 활성에 미치는 영향을 조사하기 위하여 정상대조군(NC), 고지방 식이 대조군(HC), 뽕잎차 분말을 2% 혼합한 고지방 식이군(UM), 발효 뽕잎차 분말을 2% 혼합한 고지방 식이군(FM)으로 나누어 8주간 사육하였다. 체중증가량에 있어서는 HC군의 주당 체중증가량은 NC군에 비해 2.13배로 높았으나, UM군과 FM군은 NC군의 1.80 및 1.67배로 체중증가량이 크게 완화되었다. 장기 중량은 고지방 식이군에서 증가되었던 간의 중량은 UM과 FM군에서 회복되는 경향을 보였으며, 신장의 경우에도 NC군 수준으로 회복되는 경향을 나타내었다. 부고환 주변 지방의 함량은 UM과 FM군의 경우 모두 고지방 식이로 현저하게 증가된 지방함량을 유의적으로 감소시켰으며, 그 효과는 FM군에서 현저하였다. ALT 활성은 HC군이 NC군에 비하여 2.56배나 높은 수치를 나타내었으며, UM군과 HC 간의 유의차는 보이지 않으나 FM군은 HC군에 비하여 유의적으로 낮았다. TG, TC, LDL-cholesterol의 함량 및 동맥경화지수(AI)는 HC군은 NC군에 비하여 각각 18.42%, 39.59%, 212.56% 및 230.70%가 증가하였으며, HDL-cholesterol 함량은 17.84%가 감소하였다. UM군의 TG, TC, HDL- 및 LDL-cholesterol 함량은 HC군과 유의적인 차이가 없으나, FM군에서는 유의적인 차이를 보였으며, 동맥경화지수도 HC군 2.63, UM군 2.09, FM군 1.70으로 FM군에서 양호한 결과를 나타내었다. 간 조직 TG 함량은 UM 및 FM군이 HC군에 비하여 25.18~25.72%가 감소되었으며, 총 콜레스테롤의 함량에서도 TG와 유사한 경향을 보였다. Glutathione(GSH)의 함량은 FM군이 UM군에 비하여 유의적으로 증가하였으며, lipid peroxide(LPO)의 함량은 UM군과 FM군은 HC군에 비하여 각각 49.82% 및 44.52% 감소하였다. Xanthine oxidase(XO) 활성은 UM군과 FM군에서는 HC군에 비하여 각각 38.41% 및 53.62%가 감소하였다. SOD 활성은 UM과 FM군 모두 NC군과 유사한 활성을 나타내었다. Glutathione S-transferase(GST)활성은 UM군과 FM군은 고지방 식이에 의해 감소된 HC군의 활성을 14.81~23.46% 증가시켰다. Glutathione peroxidase(GPX) 활성(NADPH nmole/min/mg protein)은 고지방 식이 대조군인 HC군에서의 활성은 NC군의 65.59%에 불과하였으나, UM군과 FM군은 HC군에 비하여 각각 22.95% 및 38.52% 증가하였다. 간 조직을 검경한 결과, 고지방 식이 대조군인 HF군에서는 간 조직 세포가 지방 방울의 축적에 의해 확장되어 간굴모세혈관(hepatic sinusoids)이 폐쇄된 상태였다. 하지만, UM군과 FM군에서는 중심정맥 주위의 세포들이 정상적으로 잘 보존되어 있으며, 간 소엽의 간세포삭과 간 조직 세포 내에 지방방울의 축적이 보이긴 하나 구분이 가능하며, UM군에 비하여 FM군 쪽의 간 손상이 보다 경미한 것으로 나타났다. 이상의 실험결과, M. pilosus로 발효시킨 뽕잎차는 정상식이군에서는 간 조직 손상과 관련된 LPO의 함량을 경감시키는 효과와 함께 경미한 체중 감소 효과가 있는 것으로 사료되며, 고지방 식이에 의한 비정상 생리 상태에서는 비만 해소와 ROS 생성계효소의 저해와 소거계 항산화 효소의 활성화를 통한 간 기능 증진과 조직 손상을 예방 또는 경감시키는 효과가 있는 것으로 생각된다.

Protection by Chrysanthemum zawadskii extract from liver damage of mice caused by carbon tetrachloride is maybe mediated by modulation of QR activity

  • Seo, Ji-Yeon;Lim, Soon-Sung;Park, Ji-A;Lim, Ji-Sun;Kim, Hyo-Jung;Kang, Hui-Jung;YoonPark, Jung-Han;Kim, Jong-Sang
    • Nutrition Research and Practice
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    • 제4권2호
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    • pp.93-98
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    • 2010
  • Our previous study demonstrated that methanolic extract of Chrysanthemum zawadskii Herbich var. latilobum Kitamura (Compositae) has the potential to induce detoxifying enzymes such as NAD(P)H:(quinone acceptor) oxidoreductase 1 (EC 1.6.99.2) (NQO1, QR) and glutathione S-transferase (GST). In this study we further fractionated methanolic extract of Chrysanthemum zawadskii and investigated the detoxifying enzyme-inducing potential of each fraction. The fraction (CZ-6) shown the highest QR-inducing activity was found to contain (+)-(3S,4S,5R,8S)-(E)-8-acetoxy-4-hydroxy-3-isovaleroyloxy-2-(hexa-2,4-diynyliden)-1,6-dioxaspiro [4,5] decane and increased QR enzyme activity in a dose-dependent manner. Furthermore, CZ-6 fraction caused a dose-dependent enhancement of luciferase activity in HepG2-C8 cells generated by stably transfecting antioxidant response element-luciferase gene construct, suggesting that it induces antioxidant/detoxifying enzymes through antioxidant response element (ARE)-mediated transcriptional activation of the relevant genes. Although CZ-6 fraction failed to induce hepatic QR in mice over the control, it restored QR activity suppressed by $CCl_4$ treatment to the control level. Hepatic injury induced by $CCl_4$ was also slightly protected by pretreatment with CZ-6. In conclusion, although CZ-6 fractionated from methanolic extract of Chrysanthemum zawadskii did not cause a significant QR induction in mice organs such as liver, kidney, and stomach, it showed protective effect from liver damage caused by $CCl_4$.

Bifenazate 저항성 점박이응애에 대한 교차저항성과 미토콘드리아 cytochrome b의 점돌연변이 (Cross Resistance and Point Mutation of the Mitochondrial Cytochrome b of Bifenazate Resistant Two-spotted Spider Mite, Tetranychus urticae)

  • 이규리;구현나;윤창만;김길하
    • 농약과학회지
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    • 제14권3호
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    • pp.247-254
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    • 2010
  • 2000년 12월 경북 칠곡의 장미재배지에서 점박이응애를 채집하여 10년 동안 bifenazate로 도태시켜 855.9배의 저항성 계통을 얻었다. 이 계통의 성충에 대한 8종 살비제의 교차저항성 유무를 조사한 결과, acequinocyl에 614.0배의 높은 교차저항성을 나타내었고, chlorfenapyr는 9.1배의 낮은 교차저항성을 나타내었다. 한편 fenazaquin(0.3배)와 fenpyroximate(0.1배)는 역상관 교차저항성을 나타내었다. 청주, 강진, 충주에서 채집한 점박이응애의 bifienazate 저항성을 확인해 본 결과, 청주와 충주의 개체군은 각각 5.5배, 21.8배의 낮은 저항성을 보였고 강진 개체군은 964.5배의 높은 저항성을 나타내었다. 또한 esterases(EST), glutathione S-transferase(GST)과 cytochrome $P_{450}$-dependent monooxygenase($P_{450}$)의 효소활성을 조사한 결과, bifenazate 저항성 점박이응애의 $P_{450}$의 활성이 감수성계통에 비해 1.6배 높은 것으로 나타났다. 감수성계통과 저항성계통의 미토콘드리아 cytochrome b의 DNA염기서열과 아미노산을 비교한 결과, G126S의 점 돌연변이(point mutation)를 확인하였고 bifenazate 약제에 높은 저항성을 보이는 강진 개체군에서도 G126S의 점 돌연변이를 확인하였다.

Association Between the GSTP1 Codon 105 Polymorphism and Gastric Cancer Risk: an Updated Meta-analysis

  • Bao, Li-Dao;Niu, Jian-Xiang;Song, Hui;Wang, Yi;Ma, Rui-Lian;Ren, Xian-Hua;Wu, Xin-Lin
    • Asian Pacific Journal of Cancer Prevention
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    • 제13권8호
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    • pp.3687-3693
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    • 2012
  • Objective: The current meta-analysis was performed to address a more accurate estimation of the association between glutathione S-transferase P1 (GSTP1) codon 105 polymorphism and risk of gastric cancer (GC), which has been widely reported with conflicting results. Methods: A comprehensive literature search was conducted to identify all the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 20 studies containing 2,821 GC cases and 6,240 controls were finally included in the analyses. Overall, no significant association between GSTP1 polymorphism and GC risk was observed in worldwide populations. However, subgroup analysis stratified by ethnicity showed that GSTP1 polymorphism was significantly associated with increased risk of GC in Asians (G vs. A, OR = 1.273, 95%CI=1.011-1.605; GG vs. AA, OR=2.103, 95%CI=1.197-3.387; GG vs. AA+AG, OR =2.103, 95%CI=1.186-3.414). In contrast, no significant association was found in Caucasians in any genetic models, except for with AG vs. AA (OR=0.791, 95%CI=0.669-0.936). Furthermore, the GSTP1 polymorphism was found to be significantly associated with GC in patients with H. pylori infection and in those with a cardiac GC. Subgroup analysis stratified by Lauren's classification and smoking status showed no significant association with any genetic model. No studies were found to significantly influence the pooled effects in each genetic mode, and no potential publication bias was detected. Conclusion: This meta-analysis suggested that the GSTP1 polymorphism might be associated with increased risk of GC in Asians, while GSTP1 heterozygote genotype seemed to be associated with reduced risk of GC. Since potential confounders could not be ruled out completely, further studies are needed to confirm these results.

Establishment of Paclitaxel-resistant Breast Cancer Cell Line and Nude Mice Models, and Underlying Multidrug Resistance Mechanisms in Vitro and in Vivo

  • Chen, Si-Ying;Hu, Sa-Sa;Dong, Qian;Cai, Jiang-Xia;Zhang, Wei-Peng;Sun, Jin-Yao;Wang, Tao-Tao;Xie, Jiao;He, Hai-Rong;Xing, Jian-Feng;Lu, Jun;Dong, Ya-Lin
    • Asian Pacific Journal of Cancer Prevention
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    • 제14권10호
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    • pp.6135-6140
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    • 2013
  • Background: Breast cancer is a common malignant tumor which affects health of women and multidrug resistance (MDR) is one of the main factors leading to failure of chemotherapy. This study was conducted to establish paclitaxel-resistant breast cancer cell line and nude mice models to explore underlying mechanisms of MDR. Methods: The breast cancer drug-sensitive cell line MCF-7 (MCF-7/S) was exposed in stepwise escalating paclitaxel (TAX) to induce a resistant cell line MCF-7/TAX. Cell sensitivity to drugs and growth curves were measured by MTT assay. Changes of cell morphology and ultrastructure were examined by optical and electron microscopy. The cell cycle distribution was determined by flow cytometry. Furthermore, expression of proteins related to breast cancer occurrence and MDR was tested by immunocytochemistry. In Vivo, nude mice were injected with MCF-7/S and MCF-7/TAX cells and weights and tumor sizes were observed after paclitaxel treatment. In addition, proteins involved breast cancer and MDR were detected by immunohistochemistry. Results: Compared to MCF-7/S, MCF-7/TAX cells had a higher resistance to paclitaxel, cross-resistance and prolonged doubling time. Moreover, MCF-7/TAX showed obvious alterations of ultrastructure. Estrogen receptor (ER) expression was low in drug resistant cells and tumors while expression of human epidermal growth factor receptor 2 (HER2) and Ki-67 was up-regulated. P-glycoprotein (P-gp), lung resistance-related protein (LRP) and glutathione-S-transferase-${\pi}$ (GST-${\pi}$) involved in the MDR phenotype of resistant cells and tumors were all overexpressed. Conclusion: The underlying MDR mechanism of breast cancer may involve increased expression of P-gp, LRP and GST-${\pi}$.

Bulnesia sarmienti 를 함유한 숙취해소 음료가 알코올대사 및 항산화 효소활성에 미치는 영향 (Effect of Alcohol Detoxification Beverage that Contained Bulnesia sarmienti on Alcohol-metabolizing Enzymes and Antioxidant Enzyme Activities)

  • 임애경;정미정;이재욱;홍주헌;김길수;정석방;김대익
    • 한국식품저장유통학회지
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    • 제18권3호
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    • pp.407-413
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    • 2011
  • 허브의 일종인 B. sarmienti를 이용하여 숙취 해소 음료를 개발하고 그에 따른 알콜 대사 및 항산화 효소에 미치는 영향을 알아보고자 하였다. 알코올을 섭취한 쥐에 B. sarmienti 음료군(BSP)을 투여 한 경우 타사 제품군인 PC 그리고 B. sarmienti만을 제외한 음료군인 NBS보다 더 뛰어난 알코올 분해능 및 ADH, ALDH에서도 뛰어난 활성을 보였다. 또한 생화학적 검사를 통해 안전성을 확인하였으며, ALP, ALT 그리고 AST에서도 PC군에 비해 유의적인 감소 효과를 보였다. 항산화 활성 및 효소계에 있어서도 BSP군에서는 GSH에서는 CO군에 비해 효소의 함량은 높으나, 다른 군에 비해 유의적인 차이는 보이지 않았으며, TBARS에는 다른 군에 비해 함량이 감소됨을 알 수 있었으나 뚜렷한 차이는 보이지 않았다. 그러나 GST, CAT 그리고 SOD 효소에 있어서는 CO군에 비해 유의적인 효소 활성이 감소되었음을 알 수 있었다. 이상과 같은 결과를 토대로 B. sarmienti 추출물이 첨가된 음료는 뛰어난 숙취 해소 및 간세포의 손상을 보호하는 음료로서 이용 가능하리라 기대 된다.

지부자 활성성분이 D-Galactosamine 투여에 의한 흰쥐의 간손상에 미치는 영향 (The Hepatoprotective Effect of Active Compounds of Kochiae fructus on D-Galactosamine-Intoxicated Rats)

  • 김나영;이정숙;박명주;이경희;김석환;최종원;박희준
    • 한국식품영양과학회지
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    • 제33권8호
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    • pp.1286-1293
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    • 2004
  • 지부자(Kochiae Fructus)의 생리활성물질 검색 및 간손상에 미치는 영향을 연구할 목적으로 실험동물에 지부자 추출물을 경구 투여한 후 GaIN으로 간손상을 유발하여 혈액 및 간조직의 생화학적 변화를 관찰하고 free radical의 생성계와 해독계의 활성에 미치는 영향을 검토한 결과는 다음과 같다. GaIN 단독투여군은 대조군에 비하여 AST와 ALT가 증가하였으나, KFB, oleanolic acid, momordin Ic 투여군에서는 GaIN 단독투여군에 비해 유의적 감소를 보였다. 간조직의 지질과산화 함량은 GaIN 단독투여군이 대조군과 비교하여 증가하였고, KFM 200-GaIN군, KFB 200-GaIN군, momordin Ic 30-GaIN군과 oleanolic acid 30-GaIN군은 대조군에는 미치지 못하였으나 GaIN 단독투여군에 비해 현저히 감소하였다. XO, AO의 활성은 대조군보다 GaIN 단독투여군에서 유의적으로 증가하였으며, KFB 200-GaIN군, momordin Ic 30-GaIN군과 oleanolic acid 30-GaIN군의 XO와 AO의 활성은 GaIN 단독투여군보다 낮게 나타났다. 간조직 중의 GSH농도는 GaIN 단독투여군이 대조군에 비해 현저히 감소하였고, KFB 200-GaIN군과 oleanolic acid 30-GaIN군은 GaIN 단독투여군과 비교시 증가를 보였고, momordin Ic 30-GaIN군은 대조군에 가깝게 회복되었다. GaIN 단독투여군의 ${\gamma}$-GCS와 GR의 활성은 대조군에 비하여 유의한 감소를 보였고, momordin Ic 30-GaIN군의 ${\gamma}$ -GCS의 활성은 대조군에는 미치지 못하였지만 GaIN 단독투여군에 비해 유의하게 개선되었다. KFM 200-GaIN군, KFB 200-GaIN군, momordin Ic 30-GaIN군과 oleanolic acid 30-GaIN군의 GR 활성은 GaIN 단독투여군보다 유의한 증가를 보였다. GST활성은 GaIN 단독투여군이 대조군에 비하여 현저한 감소를 나타내었고, KFM200-GaIN군, KFB 200-GaIN군, momordin Ic 30-GaIN군과 oleanolic acid 30-GaIN군은 대조군 수준에는 못미쳤으나 GaIN 단독투여군보다 통계적으로 유의한 증가를 관찰할 수 있었다. SOD, catalase 및 GSH-Px의 활성은 대조군에 비하여 GaIN 단독투여군에서 감소를 보였고, SOD와 catalase 활성은 KFM, KFB와 oleanolic acid의 투여로 GaIN 단독투여군보다 높게 나타났다. 특히 momordin Ic 30-GaIN군의 SOD 활성은 대조군에 가깝게 개선되었다. GSH-Px의 활성은 KFM 200-GaIN군, KFB 200-GaIN군과 oleanolic acid 30-GaIN군은 대조군 수준에는 미치지 못하였으나 GaIN 단독투여군에 비해 현저히 증가하였고, 특히 momordin Ic 30-GaIN군은 대조군에 가깝게 증가되었다. 이상의 결과를 종합하여 볼 때 지부자로부터 분리한 momordin Ic가 GSH 농도를 증가시키고 활성산소 해독계에 관여하는 효소의 활성을 증가시킴으로서 GaIN으로 인한 간손상을 완화시키는 것으로 사료되어진다.

족삼리 전침자극에 의한 흰쥐 hypothalamus의 유전자 발현 profile 분석 (Gene Expression Profile of Rat Hypothalamus Treated with Electroacupuncture at ST36 Acupoint)

  • 노삼웅;이기석;최기순;나영인;홍무창;신민규;민병일;배현수
    • 동의생리병리학회지
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    • 제18권4호
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    • pp.1041-1054
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    • 2004
  • Electroacupuncture (EA) has been reported to increase pain threshold, and to enhance the NK cell activity by up-regulation of IFN-γ and endogenous β-endolphin. For the purpose of understanding the molecular mechanism of EA stimulation, we analyzed the gene expression profile of rat hypothalamus, treated on Zusanli (ST36) with EA, in comparison with control group by oligonucleotide chip microarray (Affymetrix GeneChip Rat Neurobiology U34 Array) and real-time RT-PCR. Sprague-Dawley (S-D) male rats were stimulated at the Zusanli (ST36) acupoint in restriction holder. Simultaneously the control group was given only holder stress without EA stimulation. In order to prove the appropriateness of EA treatment, we measured spleen NK cell activity with standard 51Cr release assay. NK cell activity of EA group was significantly increased comparing to control group. The microarray and PCR results show that EA treatment up-regulates expression of genes associated with 1) nerve growth such as NGF induced factor A and VGF, 2) signal transduction such as 5HT3 receptor subunit, AMPA receptor binding protein and Na-dependent neurotransmitter transporter, and 3) anti-oxidation such as superoxide dismutase and glutathione S-transferase. In addition, the activity of the anti-oxidative enzyme, SOD of hypothalamus, liver and RBC was enhanced compared to that of control. The list of differentially expressed genes may implicate further insight on the mechanism of acupuncture effects.

Effects of dietary Antrodia cinnamomea fermented product supplementation on metabolism pathways of antioxidant, inflammatory, and lipid metabolism pathways-a potential crosstalk

  • Lee, M.T.;Lin, W.C.;Lin, L.J.;Wang, S.Y.;Chang, S.C.;Lee, T.T.
    • Asian-Australasian Journal of Animal Sciences
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    • 제33권7호
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    • pp.1167-1179
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    • 2020
  • Objective: This study was conducted to fathom the underlying mechanisms of nutrition intervention and redox sensitive transcription factors regulated by Antrodia cinnamomea fermented product (FAC) dietary supplementation in broiler chickens. Methods: Four hundreds d-old broilers (41±0.5 g/bird) assigned to 5 groups were examined after consuming control diet, or control diet replaced with 5% wheat bran (WB), 10% WB, 5% FAC, and 10% FAC. Liver mRNA expression of antioxidant, inflammatory and lipid metabolism pathways were analyzed. Prostaglandin E2 (PGE2) concentration in each group were tested in the chicken peripheral blood mononuclear cells (cPBMCs) of 35-d old broilers to represent the stress level of the chickens. Furthermore, these cells were stimulated with 2,2'-Azobis(2-amidinopropane) dihydrochloride (AAPH) and lipopolysaccharide (LPS) to evaluate the cell stress tolerance by measuring cell viability and oxidative species. Results: Heme oxygenase-1, glutathione S-transferase, glutamate-cysteine ligase, catalytic subunit, and superoxide dismutase, and nuclear factor (erythroid-derived 2)-like 2 (Nrf2) that regulates the above antioxidant genes were all up-regulated significantly in FAC groups. Reactive oxygen species modulator protein 1 and NADPH oxygenase 1 were both rather down-regulated in 10% FAC group as comparison with two WB groups. Despite expressing higher level than control group, birds receiving diet containing FAC had significantly lower expression level in nuclear factor-kappa B (NF-κB) and other genes (inducible nitric oxide synthase, tumor necrosis factor-α, interleukin-1β, nucleotide-binding domain, leucine-richcontaining family, pyrin domain-containing-3, and cyclooxygenase 2) involving in inflammatory pathways. Additionally, except for 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase that showed relatively higher in both groups, the WB, lipoprotein lipase, Acetyl-CoA carboxylase, fatty acid synthase, fatty acid binding protein, fatty acid desaturase 2 and peroxisome proliferator-activated receptor alpha genes were expressed at higher levels in 10% FAC group. In support of above results, promoted Nrf2 and inhibited NF-κB nuclear translocation in chicken liver were found in FAC containing groups. H2O2 and NO levels induced by LPS and AAPH in cPBMCs were compromised in FAC containing diet. In 35-d-old birds, PGE2 production in cPBMCs was also suppressed by the FAC diet. Conclusion: FAC may promote Nrf2 antioxidant pathway and positively regulate lipid metabolism, both are potential inhibitor of NF-κB inflammatory pathway.

Molecular characterization and docking dynamics simulation prediction of cytosolic OASTL switch cysteine and mimosine expression in Leucaena leucocephala

  • Harun-Ur-Rashid, Md.;Masakazu, Fukuta;Amzad Hossain, Md.;Oku, Hirosuke;Iwasaki, Hironori;Oogai, Shigeki;Anai, Toyoaki
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.36-36
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    • 2017
  • Out of twenty common protein amino acids, there are many kinds of non protein amino acids (NPAAs) that exist as secondary metabolites and exert ecological functions in plants. Mimosine (Mim), one of those NPAAs derived from L. leucocephala acts as an iron chelator and reversely block mammalian cell cycle at G1/S phases. Cysteine (Cys) is decisive for protein and glutathione that acts as an indispensable sulfur grantor for methionine and many other sulfur-containing secondary products. Cys biosynthesis includes consecutive two steps using two enzymes-serine acetyl transferase (SAT) and O-acetylserine (thiol)lyase (OASTL) and appeared in plant cytosol, chloroplast, and mitochondria. In the first step, the acetylation of the ${\beta}$-hydroxyl of L-serine by acetyl-CoA in the existence of SAT and finally, OASTL triggers ${\alpha}$, ${\beta}$-elimination of acetate from OAS and bind $H_2S$ to catalyze the synthesis of Cys. Mimosine synthase, one of the isozymes of the OASTLs, is able to synthesize Mim with 3-hydroxy-4-pyridone (3H4P) instead of $H_2S$ for Cys in the last step. Thus, the aim of this study was to clone and characterize the cytosolic (Cy) OASTL gene from L. leucocephala, express the recombinant OASTL in Escherichia coli, purify it, do enzyme kinetic analysis, perform docking dynamics simulation analysis between the receptor and the ligands and compare its performance between Cys and Mim synthesis. Cy-OASTL was obtained through both directional degenerate primers corresponding to conserved amino acid region among plant Cys synthase family and the purified protein was 34.3KDa. After cleaving the GST-tag, Cy-OASTL was observed to form mimosine with 3H4P and OAS. The optimum Cys and Mim reaction pH and temperature were 7.5 and $40^{\circ}C$, and 8.0 and $35^{\circ}C$ respectively. Michaelis constant (Km) values of OAS from Cys were higher than the OAS from Mim. Inter fragment interaction energy (IFIE) of substrate OAS-Cy-OASTL complex model showed that Lys, Thr81, Thr77 and Gln150 demonstrated higher attraction force for Cys but 3H4P-mimosine synthase-OAS intermediate complex showed that Gly230, Tyr227, Ala231, Gly228 and Gly232 might provide higher attraction energy for the Mim. It may be concluded that Cy-OASTL demonstrates a dual role in biosynthesis both Cys and Mim and extending the knowledge on the biochemical regulatory mechanism of mimosine and cysteine.

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