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Yang NC, Chin CY, Zheng YX, Lee I. The Attenuation of Insulin/IGF-1 Signaling Pathway Plays a Crucial Role in the Myo-Inositol-Alleviated Aging in Caenorhabditis elegans. Int J Mol Sci 2023; 24:ijms24076194. [PMID: 37047164 PMCID: PMC10094297 DOI: 10.3390/ijms24076194] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/21/2023] [Accepted: 03/23/2023] [Indexed: 03/29/2023] Open
Abstract
Myo-Inositol (MI) has been shown to alleviate aging in Caenorhabditis (C). elegans. However, the mechanism by which MI alleviates aging remains unclear. In this study, we investigate whether MI can modulate the PI3K so as to attenuate the insulin/IGF-1 signaling (IIS) pathway and exert the longevity effect. The wild-type C. elegans and two mutants of AKT-1 and DAF-16 were used to explore the mechanism of MI so as to extend the lifespan, as well as to improve the health indexes of pharyngeal pumping and body bend, and an aging marker of autofluorescence in the C. elegans. We confirmed that MI could significantly extend the lifespan of C. elegans. MI also ameliorated the pharyngeal pumping and body bend and decreased autofluorescence. We further adopted the approach to reveal the loss-of-function mutants to find the signaling mechanism of MI. The functions of the lifespan-extending, health-improving, and autofluorescence-decreasing effects of MI disappeared in the AKT-1 and DAF-16 mutants. MI could also induce the nuclear localization of the DAF-16. Importantly, we found that MI could dramatically inhibit the phosphoinositide 3-kinase (PI3K) activity in a dose-dependent manner with an IC50 of 90.2 μM for the p110α isoform of the PI3K and 21.7 μM for the p110β. In addition, the downregulation of the PI3K expression and the inhibition of the AKT phosphorylation by MI was also obtained. All these results demonstrate that MI can inhibit the PI3K activity and downregulate the PI3K expression, and the attenuation of the IIS pathway plays a crucial role for MI in alleviating aging in C. elegans.
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Chan YP, Chuang CH, Lee I, Yang NC. Lycopene in Combination With Sorafenib Additively Inhibits Tumor Metastasis in Mice Xenografted With Lewis Lung Carcinoma Cells. Front Nutr 2022; 9:886988. [PMID: 35711540 PMCID: PMC9197118 DOI: 10.3389/fnut.2022.886988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2022] [Accepted: 04/14/2022] [Indexed: 11/19/2022] Open
Abstract
Cancer metastasis is the leading cause of death in cancer patients. However, it is unclear whether lycopene can act as an adjuvant to increase the anti-metastatic activity of anticancer drugs. Here, we examined the anti-lung-metastatic effects and the mechanism of lycopene in combination with sorafenib in C57BL/6 mice xenografted with Lewis lung carcinoma (LLC) cells. The mice were divided into five groups: (1) tumor control; (2) lycopene (5 mg/kg); (3) sorafenib (30 mg/kg); (4) lycopene (2 mg/kg) + sorafenib (30 mg/kg); (5) lycopene (5 mg/kg) + sorafenib (30 mg/kg). The results showed that lycopene reduced the number of metastatic tumors in the lungs, which was further suppressed by the combined treatment with sorafenib. The activities of matrix metalloproteinase (MMP)-2 and−9 were further inhibited and TIMP-1 and−2, and NM23-H1, the MMPs negative modulators, were further activated in the combined treatment. Mechanistically, we found that lycopene and sorafenib could additively inhibit the mitogen-activated protein kinase (MAPK) pathways, as shown by the protein phosphorylation of ERK1/2, JNK1/2 and p38 were reduced additively. Overall, the present study demonstrates that lycopene in combination with sorafenib additively inhibits the lung metastasis of tumor, indicating lycopene has potential as an adjuvant for sorafenib in cancer treatment.
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Affiliation(s)
- Ya-Ping Chan
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | | | - Inn Lee
- Department of Nutrition, Chung Shan Medical University, Taichung, Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University, Taichung, Taiwan.,Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan
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3
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Lee I, Yang NC. Using Taguchi Method to Determine the Optimum Conditions for Synthesizing Parapyruvate. Molecules 2022; 27:molecules27061870. [PMID: 35335234 PMCID: PMC8954423 DOI: 10.3390/molecules27061870] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2022] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 02/01/2023] Open
Abstract
The synthesis of parapyruvate is important for the analysis of the content in the pyruvate supplements and the study of aging-related neurodegenerative diseases. However, the pure parapyruvate crystal is not, as yet, commercially available. In this study, we applied the Taguchi's L9 orthogonal array to investigate the optimal conditions for the preparation of the pure parapyruvate by the alkaline treatment of the pyruvic acid and then followed it with the solvent crystallization steps. We were also interested in revealing the major factors that affect the yield for the synthesized pure parapyruvate crystals. In addition, the parapyruvate-inhibited enzyme kinetic of α-ketoglutarate dehydrogenase complex (KGDHC) was also investigated. We found that the pure parapyruvate could be obtained in combination with an alkaline treatment and two solvent crystallization steps. The main factors affecting the yield of the pure parapyruvate were the concentration of the pyruvic acid (the reactant), the pH of the alkali treatment, the type of solvent used for the crystallization and the volume ratio of solvent used for crystallization. Finally, the optimal conditions could prepare parapyruvate crystals with a high purity of 99.8% and a high yield of 72.8%. In addition, the results demonstrate that parapyruvate is a reversibly competitive inhibitor for KGDHC.
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Affiliation(s)
- Inn Lee
- Department of Nutrition, Chung Shan Medical University, Taichung 402, Taiwan;
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University, Taichung 402, Taiwan;
- Department of Nutrition, Chung Shan Medical University Hospital, Taichung 402, Taiwan
- Correspondence: ; Tel.: +886-4-2473-0022; Fax: +886-4-2324-8175
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Yang YS, Wu NY, Kornelius E, Huang CN, Yang NC. A randomized, double-blind, placebo-controlled trial to evaluate the hypoglycemic efficacy of the mcIRBP-19-containing Momordica charantia L. fruit extracts in the type 2 diabetic subjects. Food Nutr Res 2022; 66:3685. [PMID: 35140559 PMCID: PMC8788657 DOI: 10.29219/fnr.v66.3685] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2020] [Revised: 03/24/2021] [Accepted: 09/15/2021] [Indexed: 11/23/2022] Open
Abstract
Background The fruits of Momordica charantia L., also named as bitter gourd or bitter melon in popular, is a common tropical vegetable that is traditionally used to reduce blood glucose. A peptide derived from bitter gourd, Momordica charantia insulin receptor binding peptid-19 (mcIRBP-19), had been demonstrated to possess an insulin-like effect in vitro and in the animal studies. However, the benefit of the mcIRBP-19-containing bitter gourd extracts (mcIRBP-19-BGE) for lowering blood glucose levels in humans is unknown. Objective This aim of this study was to evaluate the hypoglycemic efficacy of mcIRBP-19-BGE in subjects with type 2 diabetes who had taken antidiabetic medications but failed to achieve the treatment goal. Whether glucose lowering efficacy of mcIRBP-19-BGE could be demonstrated when the antidiabetic medications were ineffective was also studied. Design Subjects were randomly assigned to two groups: mcIRBP-19-BGE treatment group (N = 20) and placebo group (N = 20), and were orally administered 600 mg/day investigational product or placebo for 3 months. Subjects whose hemoglobin A1c (HbA1c) continued declining before the trial initiation with the antidiabetic drugs were excluded from the subset analysis to further investigate the efficacy for those who failed to respond to the antidiabetic medications. Results The oral administration of mcIRBP-19-BGE decreased with a borderline significance at fasting blood glucose (FBG; P = 0.057) and HbA1c (P = 0.060). The subgroup analysis (N = 29) showed that mcIRBP-19-BGE had a significant effect on reducing FBG (from 172.5 ± 32.6 mg/dL to 159.4 ± 18.3 mg/dL, P = 0.041) and HbA1c (from 8.0 ± 0.7% to 7.5 ± 0.8%, P = 0.010). Conclusion All of these results demonstrate that mcIRBP-19-BGE possesses a hypoglycemic effect, and can have a significant reduction in FBG and HbA1c when the antidiabetic drugs are ineffective.
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Affiliation(s)
- Yi-Sun Yang
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Chung Shan Medical University Hospital, Taichung, Taiwan
- Department of Internal Medicine, School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Nian-Yi Wu
- Department of Nutrition, Chung Shan Medical University, Taichung, Taiwan
| | - Edy Kornelius
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Chung Shan Medical University Hospital, Taichung, Taiwan
- Department of Internal Medicine, School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Chien-Ning Huang
- Department of Internal Medicine, Division of Endocrinology and Metabolism, Chung Shan Medical University Hospital, Taichung, Taiwan
- Department of Internal Medicine, School of Medicine, Chung Shan Medical University, Taichung, Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University, Taichung, Taiwan
- Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan
- Nae-Cherng Yang, Department of Nutrition, Chung Shan Medical University, Taichung 402, Taiwan.
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Lin HW, Shen TJ, Yang NC, Wang M, Hsieh WC, Chuang CJ, Lai CY, Chang YY. Luteolin Reduces Aqueous Extract PM2.5-induced Metastatic Activity in H460 Lung Cancer Cells. Int J Med Sci 2022; 19:1502-1509. [PMID: 36185331 PMCID: PMC9515691 DOI: 10.7150/ijms.73947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 08/10/2022] [Indexed: 11/25/2022] Open
Abstract
Fine particulate matter (PM2.5) is the critical cause of lung cancer and can further promote tumor cell migration and invasion. This study investigated the effects of luteolin, an antiangiogenic flavonoid agent, on blocking aqueous extract PM2.5-prompted cancer progression. We observed that luteolin reduced cell migration and the expression of pro-metastatic factors pro-matrix metalloproteinase (MMP)-2 and intercellular adhesion molecule (ICAM)-1 in PM2.5-exposed H460 lung cancer cells. Luteolin treatment also reduced the transduction of PM2.5-induced epidermal growth factor receptor (EGFR)-phosphatidylinositol 3-kinase (PI3K)-protein kinase B (AKT) cascade signaling. Furthermore, the reduction of MMP-2 expression and ICAM-1 production by luteolin in PM2.5-stimulated H460 cells is EGFR-PI3K-AKT pathway dependent. These results suggest that luteolin exhibits antitumor progression by inhibiting EGFR-PI3K-AKT pathway.
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Affiliation(s)
- Hui-Wen Lin
- Department of Optometry, Asia University, Taichung, Taiwan.,Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 40402, Taiwan
| | - Ting-Jing Shen
- Department of Microbiology and Immunology, School of Medicine, Chung-Shan Medical University, and Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University and Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Meilin Wang
- Department of Microbiology and Immunology, School of Medicine, Chung-Shan Medical University, and Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Wen-Che Hsieh
- Chinese Medicine Department, Ditmanson Medical Foundation, Chia-Yi Christian Hospital, Chia-Yi, Taiwan
| | - Chen-Ju Chuang
- Emergency department, Kaohsiung Municipal United Hospital, Kaohsiung, Taiwan
| | - Chane-Yu Lai
- Department of Occupational Safety and Health, Chung Shan Medical University, Taiwan; Department of Occupational Medicine, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Yuan-Yen Chang
- Department of Microbiology and Immunology, School of Medicine, Chung-Shan Medical University, and Clinical Laboratory, Chung Shan Medical University Hospital, Taichung, Taiwan
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Vo TLT, Yang NC, Yang SE, Chen CL, Wu CH, Song TY. Effects of Cajanus cajan (L.) millsp. roots extracts on the antioxidant and anti-inflammatory activities. CHINESE J PHYSIOL 2020; 63:137-148. [PMID: 32594067 DOI: 10.4103/cjp.cjp_88_19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
Cajanus cajan (L.) Millsp., also named pigeon pea, is widely grown in the tropics and the subtropics. C. cajan roots (CR) and ribs stewed in hot water have been used as a traditional medicine in various cultures to treat diabetes. The purpose of this study was to determine the functional components of hot water (WCR) and 50%, 95% ethanol extracts (EECR50 and EECR95) from CR, then evaluating their antioxidant and anti-inflammatory effects. The results indicated that EECR95 had higher polyphenol, especially the isoflavones (e.x. daidzein, genistein, and cajanol) than those of the other extracts, and it also exhibited the most potent anti-oxidative activities by in vitro antioxidant assay. In the lipopolysaccharide-stimulated RAW 264.7 cells, we found that EECR95 significantly decreased intracellular reactive oxygen species and significantly enhanced the activities of superoxide dismutase and catalase. Mechanism studies showed that EECR95 mainly activated nuclear factor (NF) erythroid 2-related factor 2/antioxidant protein heme oxygenase-1 and inhibited nuclear factor kappa B (NF-κB) signaling pathway, and thus exhibited antioxidant and anti-inflammatory effects. Overall, this study suggests that CR may have the potential to be developed as a biomedical material and that genistein, which has relatively high uptakes (3.44% for the pure compound and 1.73% for endogenous genistein of EECR95) at 24 h of incubation with RAW 264.7 cells, could be the main active component of CR.
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Affiliation(s)
- Thuy-Lan Thi Vo
- Department of Food Science and Biotechnology, College of Biotechnology and Bioresources, Da-Yeh University, Changhua, Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University, Taichung, Taiwan
| | - Shu-Er Yang
- Department of Beauty Science and Graduate Institute of Beauty Science Technology, Chienkuo Technology University, Changhua, Taiwan
| | - Chien-Lin Chen
- Department of Beauty Science and Graduate Institute of Beauty Science Technology, Chienkuo Technology University, Changhua, Taiwan
| | - Chi-Hao Wu
- Undergraduate Program of Nutrition Science, School of Life Sciences, National Taiwan Normal University, Taipei, Taiwan, Taiwan
| | - Tuzz-Ying Song
- Department of Food Science and Biotechnology, College of Biotechnology and Bioresources, Da-Yeh University, Changhua, Taiwan
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Chang SC, Lee I, Ting H, Chang YJ, Yang NC. Parapyruvate, an Impurity in Pyruvate Supplements, Induces Senescence in Human Fibroblastic Hs68 Cells via Inhibition of the α-Ketoglutarate Dehydrogenase Complex. J Agric Food Chem 2018; 66:7504-7513. [PMID: 29931974 DOI: 10.1021/acs.jafc.8b01138] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Commercial dietary supplements of calcium pyruvate claim to be beneficial for losing weight, increasing muscle endurance, and regulating metabolism. Most industrial preparations have some impurities, including parapyruvate. Parapyruvate is an inhibitor of the α-ketoglutarate dehydrogenase complex (KGDHC). However, the effect and mechanism of parapyruvate on cell senescence and the content of parapyruvate in the dietary supplements of calcium pyruvate are unknown. In this study, we prepared pure parapyruvate with a purity of 99.8 ± 0.1% and investigated its ability to inhibit KGDHC activity and affect fibroblast senescence. Parapyruvate dose-dependently decreased KGDHC activity, with an IC50 of 4.13 mM and induced Hs68 cell senescence. Calcium ions, a KGDHC activator, antagonized the senescent effects of parapyruvate. The parapyruvate content was 1.4 ± 0.1% to 10.6 ± 0.2% in five brands of calcium pyruvate supplements. In this study, we showed that parapyruvate strongly induces Hs68 cell senescence by inhibiting KGDHC activity. Because of its KGDHC inhibition activity, the parapyruvate content should be an important issue for the food safety of calcium pyruvate supplements.
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Affiliation(s)
- Shih-Chung Chang
- Department of Physical Medicine and Rehabilitation , Chung Shan Medical University Hospital , Taichung , Taiwan
| | - Inn Lee
- Department of Nutrition , Chung Shan Medical University , Taichung , Taiwan
| | - Hua Ting
- Department of Physical Medicine and Rehabilitation , Chung Shan Medical University Hospital , Taichung , Taiwan
- Sleep Medicine Center , Chung Shan Medical University Hospital , Taichung , Taiwan
- Institute of Medicine , Chung Shan Medical University , Taichung , Taiwan
| | - Yuan-Jhe Chang
- Department of Occupational Safety and Health , Chung Shan Medical University , Taichung , Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition , Chung Shan Medical University , Taichung , Taiwan
- Department of Nutrition , Chung Shan Medical University Hospital , Taichung , Taiwan
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8
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Jhou BY, Song TY, Lee I, Hu ML, Yang NC. Lycopene Inhibits Metastasis of Human Liver Adenocarcinoma SK-Hep-1 Cells by Downregulation of NADPH Oxidase 4 Protein Expression. J Agric Food Chem 2017; 65:6893-6903. [PMID: 28723216 DOI: 10.1021/acs.jafc.7b03036] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
NADPH oxidase 4 (NOX4), with the sole function to produce reactive oxygen species (ROS), can be a molecular target for disrupting cancer metastasis. Several studies have indicated that lycopene exhibited anti-metastatic actions in vitro and in vivo. However, the role of NOX4 in the anti-metastatic action of lycopene remains unknown. Herein, we first confirmed the anti-metastatic effect of lycopene (0.1-5 μM) on human liver adenocarcinoma SK-Hep-1 cells. We showed that lycopene significantly inhibited NOX4 protein expression, with the strongest inhibition of 64.3 ± 10.2% (P < 0.05) at 2.5 μM lycopene. Lycopene also significantly inhibited NOX4 mRNA expression, NOX activity, and intracellular ROS levels in SK-Hep-1 cells. We then determined the effects of lycopene on transforming growth factor β (TGF-β)-induced metastasis. We found that TGF-β (5 ng/mL) significantly increased migration, invasion, and adhesion activity, the intracellular ROS level, matrix metalloproteinase 9 (MMP-9) and MMP-2 activities, the level of NOX4 protein expression, and NOX activity. All these TGF-β-induced effects were antagonized by the incubation of SK-Hep-1 cells with lycopene (2.5 μM). Using transient transfection of siRNA against NOX4, we found that the downregulation of NOX4 could mimic lycopene by inhibiting cell migration and the activities of MMP-9 and MMP-2 during the incubation with or without TGF-β on SK-Hep-1 cells. The results demonstrate that the downregulation of NOX4 plays a crucial role in the anti-metastatic action of lycopene in SK-Hep-1 cells.
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Affiliation(s)
- Bo-Yi Jhou
- Department of Food Science and Biotechnology, National Chung Hsing University , Taichung, Taiwan
| | - Tuzz-Ying Song
- Department of BioIndustry Technology, Dayeh University , Changhua, Taiwan
| | - Inn Lee
- Department of Nutrition, Chung Shan Medical University , Taichung, Taiwan
| | - Miao-Lin Hu
- Department of Food Science and Biotechnology, National Chung Hsing University , Taichung, Taiwan
- Agricultural Biotechnology Center, National Chung Hsing University , Taichung, Taiwan
| | - Nae-Cherng Yang
- Department of Nutrition, Chung Shan Medical University , Taichung, Taiwan
- Department of Nutrition, Chung Shan Medical University Hospital , Taichung, Taiwan
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Yang NC, Wu CC, Liu RH, Chai YC, Tseng CY. Comparing the functional components, SOD-like activities, antimutagenicity, and nutrient compositions of Phellinus igniarius and Phellinus linteus mushrooms. J Food Drug Anal 2016; 24:343-349. [PMID: 28911588 PMCID: PMC9339555 DOI: 10.1016/j.jfda.2015.11.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2015] [Revised: 10/28/2015] [Accepted: 11/19/2015] [Indexed: 01/08/2023] Open
Abstract
Many species of the genus Phellinus possess beneficial properties, including antioxidant, immune-enhancing, and antimutagenic effects. Phenolic compounds and polysaccharides are two kinds of bioactive compounds; however, few studies have compared the differences between Phellinus igniarius and Phellinus linteus in their functional components, functional activities, and nutrient compositions. Herein, the proximate compositions and microelements of the fruiting body of P. igniarius and P. linteus were determined. The fruiting body of P. igniarius and P. linteus were extracted by boiling water [water extract of P. igniarius (WEPI) and P. linteus (WEPL)]. The contents of total phenolics and polysaccharides, as well as superoxide dismutase (SOD)-like and antimutagenic activities of WEPI and WEPL, were compared. We found that WEPI was rich in phenolics and polysaccharides and had higher SOD-like activity than WEPL. Nutrient compositions were mainly different in minerals, whereas anitmutagenicity was similar. All of these results suggested that P. igniarius has greater potential for the development of antioxidant and immunomodulating food products than P. linteus.
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Song TY, Yeh SL, Hu ML, Chen MY, Yang NC. A Nampt inhibitor FK866 mimics vitamin B3 deficiency by causing senescence of human fibroblastic Hs68 cells via attenuation of NAD(+)-SIRT1 signaling. Biogerontology 2015; 16:789-800. [PMID: 26330291 DOI: 10.1007/s10522-015-9605-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 08/27/2015] [Indexed: 12/12/2022]
Abstract
Vitamin B3 (niacin) deficiency can cause pellagra with symptoms of dermatitis, diarrhea and dementia. However, it is unclear whether the vitamin B3 deficiency causes human aging. FK866 (a Nampt inhibitor) can reduce intracellular NAD(+) level and induce senescence of human Hs68 cells. However, the mechanisms underlying FK866-induced senescence of Hs68 cells are unclear. In this study, we used FK866 to mimic the effects of vitamin B3 deficiency to reduce the NAD(+) level and investigated the mechanisms of FK866-induced senescence of Hs68 cells. We hypothesized that FK866 induced the senescence of Hs68 cells via an attenuation of NAD(+)-silent information regulator T1 (SIRT1) signaling. We found that FK866 induced cell senescence and diminished cellular NAD(+) levels and SIRT1 activity (detected by acetylation of p53), and these effects were dramatically antagonized by co-treatment with nicotinic acid, nicotinamide, or NAD(+). In contrast, the protein expression of SIRT1, AMP-activated protein kinase, mammalian target of rapamycin, and nicotinamide phosphoribosyltransferase (Nampt) was not affected by FK866. In addition, the role of GSH in the FK866-induced cells senescence may be limited, as N-acetylcysteine did not antagonize FK866-induced cell senescence. These results suggest that FK866 induces cell senescence via attenuation of NAD(+)-SIRT1 signaling. The effects of vitamin B3 deficiency on human aging warrant further investigation.
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Affiliation(s)
- Tuzz-Ying Song
- Department of BioIndustry Technology, Dayeh University, Changhua, Taiwan
| | - Shu-Lan Yeh
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan.,Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan
| | - Miao-Lin Hu
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Mei-Yau Chen
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan
| | - Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan. .,Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan.
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11
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Chuang IC, Yang CM, Song TY, Yang NC, Hu ML. The anti-angiogenic action of 2-deoxyglucose involves attenuation of VEGFR2 signaling and MMP-2 expression in HUVECs. Life Sci 2015; 139:52-61. [PMID: 26285173 DOI: 10.1016/j.lfs.2015.08.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2015] [Revised: 07/29/2015] [Accepted: 08/01/2015] [Indexed: 02/05/2023]
Abstract
AIMS 2-Deoxyglucose (2-DG) is a glucose analogue and has been shown to inhibit angiogenesis in human umbilical vascular endothelial cells (HUVECs) through interference with N-linked glycosylation. However, the anti-angiogenic mechanisms of 2-DG are not fully elucidated. MAIN METHODS We first employed an ex vivo rat aortic ring model to substantiate the anti-angiogenic action of 2-DG and then used HUVECs to investigate the molecular mechanism underlying such an action. KEY FINDINGS Results reveal that 2-DG (0.05-1.0mM) significantly inhibited tube formation in both rat aortic rings and HUVECs. 2-DG (0.1-1.0mM) also significantly inhibited cell invasion and migration, as well as the activity and mRNA and protein expression of matrix metalloproteinase (MMP)-2 in HUVECs. In addition, 2-DG (1.0mM) significantly inhibited mRNA and protein expression of vascular endothelial growth receptor 2 (VEGFR2) in a time-dependent manner. 2-DG also significantly inhibited the phosphorylation of the focal adhesion kinase (FAK) and mitogen-activated protein kinase (p38), the downstream molecules of VEGFR2. The effects of 2-DG on tube formation, MMP-2 activity, and VEGFR2 protein expression in HUVECs were reversed by mannose, an N-linked glycosylation precursor. Mannose also reversed 2-DG-induced accumulation of VEGFR2 in the endoplasmic reticulum. SIGNIFICANCE This ex vivo and in vitro study demonstrates that 2-DG inhibits angiogenesis with an action involving attenuation of VEGFR2 signaling and MMP-2 expression, possibly resulting from interference with N-linked glycosylation of VEGFR2. Further studies are needed to show that 2-DG inhibits VEGF-mediated angiogenesis or that the actual status of N-glycosylation of VEGFR2 is affected by the treatment.
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Affiliation(s)
- I-Chen Chuang
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Chih-Min Yang
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan
| | - Tuzz-Ying Song
- Department of BioIndustry Technology, Dayeh University, Changhua, Taiwan
| | - Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan; Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan.
| | - Miao-Lin Hu
- Department of Food Science and Biotechnology, National Chung Hsing University, Taichung, Taiwan; Agricultural Biotechnology Center, National Chung Hsing University, Taichung, Taiwan.
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12
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Chen YC, Kuo YH, Yang NC, Liu CW, Chang WT, Hsu CL. Cytotoxic and apoptotic effects of caffeate derivatives on A549 human lung carcinoma cells. J Chin Med Assoc 2014; 77:535-43. [PMID: 25153015 DOI: 10.1016/j.jcma.2014.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2013] [Accepted: 05/02/2014] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND Caffeate derivatives have been reported to exhibit antioxidant, anti-inflammatory, and anticancer activities. To reveal the cytotoxic and apoptotic effects of caffeate derivatives, we studied the effects of octyl, phenylpropyl, and decyl caffeates on cell growth and apoptosis in A549 human lung carcinoma cells. METHODS A549 human lung carcinoma cells were treated with 0-100 μM of caffeate derivatives for 0-48 hours. The cytotoxic and apoptotic effects were evaluated by a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay for cell viability, propidium iodide staining method for cell morphology, mitochondrial membrane potential analysis, and Western blot for protein expression. RESULTS Octyl, phenylpropyl, and decyl caffeates all significantly decreased the cell viability of A549 cells with 50% inhibitory concentration values of 54.2 ± 10.1 μM, 80.2 ± 1.3 μM, and 74.9 ± 2.1 μM, respectively. Propidium iodide staining revealed that apoptotic bodies appeared when cells were treated with octyl and decyl caffeates. Treatment of A549 cells with octyl and decyl caffeates caused the loss of mitochondria membrane potential. Western blots revealed that octyl and decyl caffeates stimulate an increase in the protein levels of Fas, FasL, and Apaf-1. Moreover, these compounds changed the levels of pro- and antiapoptotic Bcl-2 family members and induced the activation of caspase-12, -9, and -3, which was followed by cleavage of poly (ADP-ribose) polymerase. CONCLUSION These results demonstrate that octyl and decyl caffeates induce cell apoptosis in A549 human lung carcinoma cells.
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Affiliation(s)
- Yi-Chen Chen
- Department of Animal Science and Technology, National Taiwan University, Taipei, Taiwan, ROC
| | - Yueh-Hsiung Kuo
- Department of Chinese Pharmaceutical Sciences and Chinese Medicine Resources, China Medical University, Taichung, Taiwan, ROC; Department of Biotechnology, Asia University, Taichung, Taiwan, ROC
| | - Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan, ROC
| | - Cheng-Wei Liu
- Department of Post-Modern Agriculture, MingDao University, ChangHua, Taiwan, ROC; Department of Biotechnology, MingDao University, ChangHua, Taiwan, ROC
| | - Wei-Tang Chang
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan, ROC
| | - Chin-Lin Hsu
- School of Nutrition, Chung Shan Medical University, Taichung, Taiwan, ROC; Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC.
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Yang NC, Song TY, Chang YZ, Chen MY, Hu ML. Up-regulation of nicotinamide phosphoribosyltransferase and increase of NAD+ levels by glucose restriction extend replicative lifespan of human fibroblast Hs68 cells. Biogerontology 2014; 16:31-42. [PMID: 25146190 DOI: 10.1007/s10522-014-9528-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 08/13/2014] [Indexed: 10/24/2022]
Abstract
Calorie restriction (CR) extends lifespan in a remarkable range of organisms. However, the mechanisms of CR related to the longevity effects are not fully elucidated to date. Using human fibroblast Hs68 (Hs68) cells cultured at a lower level of medium glucose (i.e., glucose restriction; GR) to mimic CR, we investigated the crucial role of nicotinamide phosphoribosyltransferase (Nampt), nicotinamide adenine dinucleotide (NAD(+)), and nicotinamide (NAM) in GR-extended replicative lifespan of Hs68 cells. We found that GR extended the lifespan of Hs68 cells, in parallel to significantly increased expression of Nampt, intracellular NAD(+) levels, and SIRT1 activities, and to significantly decreased NAM levels. The lifespan-extending effects of GR were profoundly diminished by FK866 (a noncompetitive inhibitor of Nampt) and blocked by sirtinol (a noncompetitive inhibitor of sirtuins). However, the steady-state intracellular NAM level (averaged 2.5 μM) was much lower than the IC50 of NAM on human SIRT1 (about 50 μM). All these results suggest that up-regulation of Nampt play an important role in GR-extended lifespan of Hs68 cells by increasing the intracellular NAD(+) levels followed by activating SIRT1 activity in Hs68 cells. In contrast, the role of NAM depletion is limited.
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Affiliation(s)
- Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd., Taichung City, 40201, Taiwan, ROC,
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Chan ST, Yang NC, Huang CS, Liao JW, Yeh SL. Quercetin enhances the antitumor activity of trichostatin A through upregulation of p53 protein expression in vitro and in vivo. PLoS One 2013; 8:e54255. [PMID: 23342112 PMCID: PMC3546961 DOI: 10.1371/journal.pone.0054255] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Accepted: 12/10/2012] [Indexed: 01/02/2023] Open
Abstract
This study investigated the effects of quercetin on the anti-tumor effect of trichostatin A (TSA), a novel anticancer drug, in vitro and in vivo and the possible mechanisms of these effects in human lung cancer cells. We first showed that quercetin (5 µM) significantly increased the growth arrest and apoptosis in A549 cells (expressing wild-type p53) induced by 25 ng/mL of (82.5 nM) TSA at 48 h by about 25% and 101%, respectively. However, such enhancing effects of quercetin (5 µM) were not significant in TSA-exposed H1299 cells (a p53 null mutant) or were much lower than in A549 cells. In addition, quercetin significantly increased TSA-induced p53 expression in A549 cells. Transfection of p53 siRNA into A549 cells significantly but not completely diminished the enhancing effects of quercetin on TSA-induced apoptosis. Furthermore, we demonstrated that quercetin enhanced TSA-induced apoptosis through the mitochondrial pathway. Transfection of p53 siRNA abolished such enhancing effects of quercetin. However, quercetin increased the acetylation of histones H3 and H4 induced by TSA in A549 cells, even with p53 siRNA transfection as well as in H1299 cells. In a xenograft mouse model of lung cancer, quercetin enhanced the antitumor effect of TSA. Tumors from mice treated with TSA in combination with quercetin had higher p53 and apoptosis levels than did those from control and TSA-treated mice. These data indicate that regulation of the expression of p53 by quercetin plays an important role in enhancing TSA-induced apoptosis in A549 cells. However, p53-independent mechanisms may also contribute to the enhancing effect of quercetin.
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Affiliation(s)
- Shu-Ting Chan
- Department of Nutritional Science, Chung Shan Medical University, Taichung, Taiwan
| | - Nae-Cherng Yang
- Department of Nutritional Science, Chung Shan Medical University, Taichung, Taiwan
| | - Chin-Shiu Huang
- Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan
| | - Jiunn-Wang Liao
- Graduate Institute of Veterinary Pathology, College of Veterinary Medicine, National Chung Hsing University, Taichung, Taiwan
| | - Shu-Lan Yeh
- Department of Nutritional Science, Chung Shan Medical University, Taichung, Taiwan
- Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan
- * E-mail:
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Ou HC, Hsieh YL, Yang NC, Tsai KL, Chen KL, Tsai CS, Chen IJ, Wu BT, Lee SD. Ginkgo biloba extract attenuates oxLDL-induced endothelial dysfunction via an AMPK-dependent mechanism. J Appl Physiol (1985) 2012. [PMID: 23195633 DOI: 10.1152/japplphysiol.00367.2012] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Atherosclerosis is a complex inflammatory arterial disease, and oxidized low-density lipoprotein (oxLDL) is directly associated with chronic vascular inflammation. Previous studies have shown that Ginkgo biloba extract (GbE) acts as a therapeutic agent for neurological and cardiovascular disorders. However, the mechanisms mediating the actions of GbE are still largely unknown. In the present study, we tested the hypothesis that GbE protects against oxLDL-induced endothelial dysfunction via an AMP-activated protein kinase (AMPK)-dependent mechanism. Human umbilical vein endothelial cells were treated with GbE, followed by oxLDL, for indicated time periods. Results from Western blot showed that GbE inhibited the membrane translocation of the NADPH oxidase subunits p47(phox) and Rac-1 and attenuated the increase in protein expression of membrane subunits gp91 and p22(phox) caused by oxLDL-induced AMPK dephosphorylation and subsequent PKC activation. AMPK-α(1)-specific small interfering RNA-transfected cells that had been exposed to GbE followed by oxLDL revealed elevated levels of PKC and p47(phox). In addition, exposure to oxLDL resulted in reduced AMPK-mediated Akt/endothelial nitric oxide (NO) synthase signaling and the induction of phosphorylation of p38 mitogen-activated protein kinase, which, in turn, activated NF-κB-mediated inflammatory responses, such as the release of interleukin-8, the expression of the adhesion molecule, and the adherence of monocytic cells to human umbilical vein endothelial cells. Furthermore, oxLDL upregulated the expression of inducible NO synthase, thereby augmenting the formation of NO and protein nitrosylation. Pretreatment with GbE, however, exerted significant cytoprotective effects in a dose-dependent manner. Results from this study may provide insight into a possible molecular mechanism by which GbE protects against oxLDL-induced endothelial dysfunction.
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Affiliation(s)
- Hsiu-Chung Ou
- Department of Physical Therapy and Graduate Institute of Rehabilitation Science, China Medical University, Taichung, Taiwan
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Yang NC, Lin HC, Wu JH, Ou HC, Chai YC, Tseng CY, Liao JW, Song TY. Ergothioneine protects against neuronal injury induced by β-amyloid in mice. Food Chem Toxicol 2012; 50:3902-11. [PMID: 22921351 DOI: 10.1016/j.fct.2012.08.021] [Citation(s) in RCA: 61] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/23/2012] [Accepted: 08/09/2012] [Indexed: 01/05/2023]
Abstract
β-Amyloid peptides (Aβ) are neurotoxic and contribute to the development of Alzheimer's disease (AD). Ergothioneine (EGT) has been shown to protect against loss of memory and learning abilities in mice. In this study, mice were orally fed EGT (0.5 or 2 mg/kg body weight) for 16 days before treatment (i.c.v) with a single dose of Aβ1-40 in the hippocampus. After resting for 12 days to restore the body weight, the mice were again fed EGT for additional 39 days. Active avoidance tests were conducted on days 37-39 (short-memory avoidance) and on days 37, 44 and 51 (long-memory avoidance). Water maze task was used to evaluate learning and memory abilities by acquisition test and retention test. In both long-memory avoidance and water maze tests, EGT significantly decreased the escape latency and increased the frequency of successful avoidance. Furthermore, EGT significantly prevented Aβ accumulation in the hippocampus and brain lipid peroxidation, restored acetylcholinesterase (AChE) activity, maintained glutathione/glutathione disulfide ratio and superoxide dismutase activity in brain tissues of Aβ1-40-teated mice. Thus, EGT can protect against Aβ-induced loss of memory and learning abilities in mice. Further studies are required to confirm the protective effects of EGT on the development or progression of AD.
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Affiliation(s)
- Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University and Department of Nutrition, Chung Shan Medical University Hospital, Taichung, Taiwan, ROC
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Yang NC, Jhou KY, Tseng CY. Antihypertensive effect of mulberry leaf aqueous extract containing γ-aminobutyric acid in spontaneously hypertensive rats. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.11.143] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Yang NC, Song TY, Chen MY, Hu ML. Effects of 2-deoxyglucose and dehydroepiandrosterone on intracellular NAD(+) level, SIRT1 activity and replicative lifespan of human Hs68 cells. Biogerontology 2011; 12:527-36. [PMID: 21604001 DOI: 10.1007/s10522-011-9342-7] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2011] [Accepted: 05/10/2011] [Indexed: 10/18/2022]
Abstract
2-Deoxy-D-glucose (2-DG) and dehydroepiandrosterone (DHEA) have been hypothesized to extend lifespan via mimicking calorie restriction (CR). Activation of sirtuins has been proposed to contribute to life extension of CR by increasing intercellular levels of NAD(+) in several organisms. However, it is unclear whether 2-DG and DHEA may affect intracellular NAD(+) levels and human sirtuin 1 (SIRT1) activities. Here, using human fibroblast Hs68 cells we showed that 2-DG increased intracellular NAD(+) levels in both time- and concentration-dependent manners. 2-DG also dose-dependently increased SIRT1 activities and the lifespan (measured as the cumulated growth curve of population doubling levels) of Hs68 cells. In contrast, DHEA at non-cytotoxic concentrations (≤50 μM) did not significantly affect NAD(+) levels, SIRT1 activities or the lifespan of Hs68 cells. These results suggest that 2-DG extends the lifespan of Hs68 cells by increased NAD(+) levels and SIRT1 activities, and that 2-DG has a potential as a CR mimetic.
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Affiliation(s)
- Nae-Cherng Yang
- School of Nutrition, Chung Shan Medical University and Department of Nutrition, Chung Shan Medical University Hospital, Taiwan, ROC
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19
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Tsai CH, Chiu WC, Yang NC, Ouyang CM, Yen YH. A novel green tea meal replacement formula for weight loss among obese individuals: a randomized controlled clinical trial. Int J Food Sci Nutr 2009; 60 Suppl 6:151-9. [DOI: 10.1080/09637480903136667] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Hsia CH, Shen MC, Lin JS, Wen YK, Hwang KL, Cham TM, Yang NC. Nattokinase decreases plasma levels of fibrinogen, factor VII, and factor VIII in human subjects. Nutr Res 2009; 29:190-6. [DOI: 10.1016/j.nutres.2009.01.009] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2008] [Revised: 01/21/2009] [Accepted: 01/28/2009] [Indexed: 10/20/2022]
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Yang NC, Chou CW, Chen CY, Hwang KL, Yang YC. Combined nattokinase with red yeast rice but not nattokinase alone has potent effects on blood lipids in human subjects with hyperlipidemia. Asia Pac J Clin Nutr 2009; 18:310-317. [PMID: 19786378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
The purpose of this randomized, double-blind, placebo-controlled, parallel comparison study was to evaluate the lipid-lowering effect of orally administrated nattokinase and nattokinase combined with red yeast rice (RYR) extract on blood lipids in patients with hyperlipidemia. A total of 47 patients with hyperlipidemia were assigned to one of three groups: 1. nattokinase-mono formula (50 mg/capsule), 2. combined formula of nattokinase with RYR (300 mg of extract/capsule) and 3. placebo. Subjects received a twice daily dose of two capsules for six months. The mono formula showed no effects on blood lipids until month six, while the combined formula ameliorated all of measured lipids starting from month one. In the combined group significant decreases were found with regard to: triglycerides (TG) by 15%, total cholesterol (TC) by 25%, low-density lipoprotein cholesterol (LDL-C) by 41%, TC/high-density lipoprotein cholesterol (HDL-C) ratio by 29.5%, and increases in HDL-C by 7.5%. These changes were sustained until the end of study. After controlling for baseline levels, only the combined group, but not mono group, showed a significant difference (p<0.0001) in TC, LDL-C and TC/HDL-C ratio when compared with the placebo group. In summary, this study provides long-term efficacy of nattokinase supplementation and shows that the combined formula has relatively more potent effects than the mono formula on lowering of blood lipids, suggesting that combined nattokinase with RYR will be a better neutraceutical for patients with hyperlipidemia than nattokinase alone.
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Affiliation(s)
- Nae-Cherng Yang
- Department of Nutrition and Health Science, Chungchou Institute of Technology, Changhua 510, Taiwan.
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Song TY, Lin HC, Yang NC, Hu ML. Antiproliferative and antimetastatic effects of the ethanolic extract of Phellinus igniarius (Linnearus: Fries) Quelet. J Ethnopharmacol 2008; 115:50-56. [PMID: 17936529 DOI: 10.1016/j.jep.2007.09.001] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2007] [Revised: 08/20/2007] [Accepted: 09/04/2007] [Indexed: 05/25/2023]
Abstract
AIM OF THIS STUDY Phellinus igniarius (Linnearus: Fries) Quelet (Phellinus igniarius) has been used in oriental countries for treatment of various diseases including cancer. However, it is unclear how Phellinus igniarius exerts anticancer effects. MATERIALS AND METHODS In this study the ethanolic extract from the fruiting body of Phellinus igniarius (EEPI) was used to evaluate the antiproliferative and antimetastatic effects in human hepatocarcinoma SK-Hep-1 cells and rat heart vascular endothelial cells (RHE cells). RESULTS We found that EEPI inhibited the proliferation of both cell lines in a dose-dependent manner, and the IC50 values at 48 h were 72 and 103 microg/ml for SK-Hep-1 cells and RHE cells, respectively. EEPI at non- or sub-cytotoxic concentrations (25-100 microg/ml) markedly inhibited the migration and invasion of SK-Hep-1 cells. EEPI added at 25 microg/ml significantly decreased the secretion of matrix metalloproteinase-2 (MMP-2) (49%, p<0.01) and vascular endothelial growth factor (VEGF) (13%, p<0.05) in SK-Hep-1 cells. EEPI at 25 microg/ml completely inhibited matrigel-induced tube formation in RHE cells. Importantly, EEPI (25 or 50 microg/ml) in combination with oxaliplatin (Oxa) or 5-flurouracil (5-FU) synergistically inhibited the proliferation of SK-Hep-1 cells. CONCLUSION These results demonstrate the antiproliferative and antimetastatic effects of EEPI in vitro and the potential of EEPI as an adjuvant for chemotherapy.
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Affiliation(s)
- Tuzz-Ying Song
- Department of Nutrition and Health Science, Chungchou Institute of Technology, Changhua, Taiwan, ROC
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Abstract
BACKGROUND We have previously proposed an equation derived from Fick's law and Lin's concept of effective blood concentration (EBC) to calculate the mixed venous blood concentration (MVBC) of isoflurane. Desflurane has a lower blood/air partition coefficient than isoflurane and, as such, promotes a faster induction and recovery from anesthesia. In this study, we investigated the application of the MVBC equation to predict the MVBC of desflurane. METHODS We maintained anesthesia with a fixed inspired concentration (CI) of desflurane (10%) during cardiac anesthesia in 11 patients. In order to measure the real concentrations of desflurane in mixed venous blood, pulmonary arterial blood samples were collected at different time points via a Swan-Ganz catheter for gas chromatographic-mass spectrometric determination. The relationship between the calculated concentrations and the actual blood sample concentrations of desflurane in mixed venous blood was investigated. Lin's EBC method was also used and the results were compared with those of MVBC. RESULTS The calculations from our derived MVBC equation and the actual blood concentrations showed a similar kinetic pattern; the concentration levels were approximately the same and correlated well (r = 0.89) during anesthesia. However, the EBC method failed to accurately estimate the actual blood concentrations. CONCLUSIONS The results demonstrate that our equation, but not the EBC method, may be useful for estimating pulmonary blood concentrations of desflurane. The clinical significance and the importance of the method merit further investigation.
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Affiliation(s)
- C C Wu
- Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan
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Yang NC, Hu ML. The limitations and validities of senescence associated-beta-galactosidase activity as an aging marker for human foreskin fibroblast Hs68 cells. Exp Gerontol 2005; 40:813-9. [PMID: 16154306 DOI: 10.1016/j.exger.2005.07.011] [Citation(s) in RCA: 146] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2005] [Accepted: 07/26/2005] [Indexed: 11/19/2022]
Abstract
The senescence associated-beta-galactosidase (SA-betaG) assay has become one of the most commonly used markers of cell-aging. However, the reliability of the assay is questionable because the enzyme is a non-specific marker for cell-aging. In this study, we found that the SA-betaG activity increased with cell age as well as in confluent quiescent cells or cells under serum starvation, and in cells treated with H2O2. Importantly, we found that SA-betaG activity was irreversibly increased in the senescent cells or H2O2-teated cells, but was reversible in quiescent cells induced by serum starvation or confluence. Using fluorescein di-beta-d-galactopyranoside (FDG) method for SA-betaG detection, we showed that senescent human foreskin fibroblast Hs68 cells did not express a specific enzyme that has a maximal activity at pH 6.0. In the pH profile of the cellular betaG activity in senescent Hs68 cells, only a single peak was found (with maximum at pH 4.6), and no addition peak was found at or around pH 6.0 that could be attributed to the SA-betaG activity. These results support the contention that SA-betaG is the lysosomal betaG that is detectable at suboptimal pH (i.e. pH 6.0) and demonstrate that cell-aging is not the only factor that can increase SA-betaG activity, rendering SA-betaG activity unspecific for cell-aging. Thus, the assay for cell-aging is only reliable when these confounding factors are controlled or excluded.
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Affiliation(s)
- Nae-Cherng Yang
- Department of Biotechnology, Chungchou Institute of Technology, Changhua, Taiwan, ROC
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Ho WM, Hung WT, Wu CC, Shen CH, Yang NC, Hwang KL, Wong KC. Application of MVBC equation to predict mixed venous blood concentrations of sevoflurane in cardiac anaesthesia. Anaesthesia 2005; 60:882-6. [PMID: 16115250 DOI: 10.1111/j.1365-2044.2005.04280.x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We have proposed an equation for estimating the real-time mixed venous blood concentration (MVBC) of isoflurane in cardiac anaesthesia. However, information related to the application of our method to sevoflurane is lacking. We studied 12 patients undergoing cardiac surgery and anaesthetised with sevoflurane. At different time points, pulmonary arterial blood samples were collected for gas chromatography-mass spectrometry (GC-MS) to determine the real mixed venous concentrations of sevoflurane. The inspired and expired concentrations of sevoflurane, measured by a gas monitor, were used for the MVBC calculations. Using Bland-Altman analyses, we found that the calculated MVBCs accurately represent the actual concentrations of sevoflurane in pulmonary arterial blood, as shown by a near-zero percentage bias with a 0.14% precision between the two concentrations. The results demonstrated that our equation could be a useful method for estimating the pulmonary blood concentration of sevoflurane.
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Affiliation(s)
- W-M Ho
- Department of Anaesthesia, Taichung Veterans General Hospital and Chung Shan Medical University, Taichung, Taiwan.
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Yang NC, Wang HF, Hwang KL, Ho WM. A Novel Method for Determining the Blood/Gas Partition Coefficients of Inhalation Anesthetics to Calculate the Percentage of Loss at Different Temperatures. J Anal Toxicol 2004; 28:122-7. [PMID: 15068566 DOI: 10.1093/jat/28.2.122] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The loss by blood/gas (lambda) partition of inhalation anesthetics can be estimated by an equation for the percentage of loss. However, because lambdas of inhalation anesthetics at different temperatures have not been fully determined so far, the percentage of loss at varying temperature in various headspace volumes cannot be estimated. Therefore, a novel method was developed for the determination of inhalation anesthetic lambda, in this study. The method was precise, with a relative standard deviation of less than 5%. The average of lambda from seven distinct blood samples at 4 degrees C, 25 degrees C, and 37 degrees C were determined as 6.68, 2.04, and 1.32 of isoflurane; 3.47, 1.10, and 0.65 of sevoflurane; and 2.31, 0.75, and 0.46 of desflurane, respectively. In addition, increasing temperature was found to decrease lambda profoundly by a secondary order mechanism. Using the obtained value of lambda, the percentage of loss of isoflurane, sevoflurane, and desflurane were then predicted using a 5-mL vacuum tube as a collecting container for an example. In conclusion, a novel method was developed here for lambda determination, and lambdas of isoflurane, sevoflurane, and desflurane at various temperatures were given for estimating the loss resulting from liquid/gas partitioning.
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Affiliation(s)
- N C Yang
- Department of Anesthesiology, Taichung Veterans General Hospital, Taichung, Taiwan
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Yang NC, Hu ML. A fluorimetric method using fluorescein di-β-d-galactopyranoside for quantifying the senescence-associated β-galactosidase activity in human foreskin fibroblast Hs68 cells. Anal Biochem 2004; 325:337-43. [PMID: 14751269 DOI: 10.1016/j.ab.2003.11.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The senescence-associated beta-galactosidase (SA-betaG) assay is one of the few accepted markers of cell aging. However, the cytochemical method using 5-bromo-4-chloro-3-indolyl beta-D-galactopyranoside (X-Gal) as substrate is limited in sensitivity and is only semiquantitative. Here, we modified the X-Gal method by replacing X-Gal with fluorescein di-beta-D-galactopyranoside (FDG) as substrate for SA-betaG, and the activity was measured fluorimetrically. We showed in Hs68 cells that the FDG fluorescein fluorescence increased with increasing passages of the cells in parallel with the X-Gal method. A major advantage of the FDG method is that it is a quantitative method for the SA-betaG activity. For example, we showed that the FDG fluorescein in p30(+1) of Hs68 cells was generally stronger than that in p26(+1) cells, whereas the X-Gal method gave similar results (95 and 100%) for p26(+1) and p30(+1) cells. The FDG method was precise with a relative standard deviation lower than 10%. We further demonstrated that FDG and X-Gal could be added simultaneously for SA-betaG assay because the FDG fluorescein diffused readily through formaldehyde-fixed cell membrane and could be detected in the suspension buffer. Thus, a double-substrate method, i.e., X-Gal for rapid qualitative assay and FDG for quantitative assay, can be conducted simultaneously to provide a simple and reliable assay of SA-betaG activity as a marker of cell aging.
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Affiliation(s)
- Nae-Cherng Yang
- Department of Food Science, National Chung-Hsing University, 402, Taichung, Taiwan
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Abstract
It has been proposed that hyperhomocysteinemia may exert its pathogenic effects largely through metabolic accumulation of S-adenosylhomocysteine (SAH), a strong noncompetitive inhibitor of most methyltransferases. Here, we investigated the effects of SAH on H(2)O(2)-induced cellular DNA damage in comparison with the effects of homocysteine (Hcy) in a mouse endothelial cell line and a human intestinal cell line. Cells were preincubated for 2 h with H(2)O(2) (20 microM) followed by incubation with SAH or Hcy for 3 h. DNA strand breakage was determined using comet assay and DNA repair capacity determined using the same assay over time at 1, 2, and 3 h during SAH incubation. In both types of cells, SAH at 0.25-2 microM strongly and dose dependently enhanced H(2)O(2)-dependent DNA damage and inhibited DNA repair, whereas Hcy had a much weaker effect. SAH markedly increased uracil misincorporation, and this effect was also much stronger than that of Hcy. Taken together, our results show that SAH potentiates H(2)O(2)-induced DNA damage in cell cultures through impaired DNA repair capability and suggest that such effects are related to uracil misincorporation. Although the in vivo relevance of our findings is unclear, the biological significance of SAH-mediated detrimental effect, secondary to elevated intracellular Hcy, is an interesting area awaiting further exploration.
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Affiliation(s)
- Tsai-Hsiu Yang
- Department of Food Science, National Chung-Hing University, 250 Kuo-Kuang Road, Taichung, Taiwan 402, ROC
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29
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Abstract
Cellular ATP is commonly determined as production of bioluminescence using a luciferin-luciferase reaction system. Before the measurement of bioluminescence, cellular ATP must first be extracted. Two commonly used extraction methods are: () Tris-borate buffer (pH 9.2) coupled with a heating process (to inactivate ATPase) and () perchloric acid followed by neutralization. However, we found that both Tris-borate buffer and perchloric acid interfered with the luciferin-luciferase system. Here, we report a convenient single-step boiling deionized water (DW) method for extracting cellular ATP to replace perchloric acid and Tris-borate buffer. We showed that the boiling DW method did not interfere with the bioluminescence and was effective in inhibiting ATPase. This improved method required no neutralization and dilution and thus was more convenient than the perchloric acid method. Unlike the Tris-borate/heating procedure, our method did not require a separate heating step because boiling DW effectively inhibited ATPase and thus accomplished the two missions in one step for both suspended and attached cells. The improved method was precise for both suspended cells and attached cells, when cell numbers were between 10(3) and 10(6). The method also was more sensitive than other methods because it required much fewer cells (10(4) to 10(5)) than other methods for ATP determination. Thus, this one-step method is suitable for routine assay of cellular ATP for both suspended and attached cells.
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Affiliation(s)
- Nae-Cherng Yang
- Department of Food Science, National Chung-Hsing University, Taichung 402, Taiwan
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30
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Abstract
Dehydroepiandrosterone (DHEA), a major steroid secreted by the adrenal gland, is known to have antiproliferative effects but the mechanism is unclear. We recently reported that DHEA induces growth inhibition and apoptosis in BV-2 cells and these effects are inversely associated with glucose concentrations in the medium. Here, we further showed that incubation of BV-2 cells with DHEA under glucose deprivation (G0) led to dose- and time-dependent decrease in cellular ATP levels. The decrease in ATP preceded growth inhibition and apoptosis induced by DHEA and all these effects of DHEA (i.e., loss of ATP, antiproliferation and apoptosis) were prevented by glucose added at 4.5 mg/ml (G4.5) during incubation. In addition, two ATP-depleting agents, iodoacetic acid (IAA) and 2,4-dinitrophenylhydrazine (2,4-DNP), potentiated the antiproliferative and apoptotic effects of DHEA. We also determined whether decrease in nucleic acid synthesis (due to glucose-6-phosphate dehydrogenase inhibition by DHEA) contributes to DHEA-induced antiproliferation and apoptosis. Using a mixture of deoxyribonucleotides (DN) and ribonucleotides (RN), we showed that DNRN had little or no effect on DHEA-induced growth inhibition and apoptosis. We also showed that mevalonic acid (MVA) did not affect DHEA-induced antiproliferation and apoptotic effects, indicating that protein isoprenylation and membrane association are not affected by DHEA in BV-2 cells. Taken together, the present results demonstrate that depletion of ATP by DHEA plays an important role in DHEA-induced antiproliferation and apoptosis of BV-2 cells.
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Affiliation(s)
- Nae-Cherng Yang
- Department of Food Science, National Chung-Hsing University, Taichung, Taiwan
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31
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Yang NC, Hwang KL, Shen CH, Wang HF, Ho WM. Simultaneous determination of fluorinated inhalation anesthetics in blood by gas chromatography-mass spectrometry combined with a headspace autosampler. J Chromatogr B Biomed Sci Appl 2001; 759:307-18. [PMID: 11499484 DOI: 10.1016/s0378-4347(01)00239-0] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Although the fluorinated inhalation anesthetics, including desflurane, sevoflurane, isoflurane, enflurane, and halothane are commonly used, fatal cases resulting from their abuse or misuse have been reported. To date, gas chromatography (GC) equipped with different kinds of detectors has been utilized to analyze inhalation anesthetics. However, none of them can detect desflurane reliably or analyze all five common anesthetics simultaneously. The purpose of the present work is to further modify the previously developed headspace (HS) GC-MS method for blood isoflurane determination to analyze and distinguish five common clinical inhalation anesthetics, simultaneously. The modified HS-GC-MS method adopts a 60 m x 0.25 mm I.D., 0.25 microm film thickness DB-5 capillary column along with an adequate GC temperature program, which gives the five inhalation anesthetics, including isoflurane and its isomer, enflurane, a high resolution. The method also takes both the volatility and the influence of the top space on the obtained concentration into consideration and therefore keeps the sample loss acceptable even for analyzing the highly volatile desflurane. Within a certain concentration range of the calibration standard (about 20-300 microg/ml), this method shows a good linearity with correlation coefficients greater than 0.999. In addition, both within- and between-run precision and accuracy results meet the validation requirements as well as the tested results of practical blood samples of desflurane. In summary, this is a reliable analytical method to simultaneously determine the concentration of five common inhalation anesthetics in blood. Such a method is very practical for both clinical and occupational monitoring, as well as for analytical toxicology.
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Affiliation(s)
- N C Yang
- Department of Anesthesiology, Taichung Veterans General Hospital, Taiwan
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32
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Yang NC, Jeng KC, Ho WM, Chou SJ, Hu ML. DHEA inhibits cell growth and induces apoptosis in BV-2 cells and the effects are inversely associated with glucose concentration in the medium. J Steroid Biochem Mol Biol 2000; 75:159-66. [PMID: 11226832 DOI: 10.1016/s0960-0760(00)00180-1] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dehydroepiandrosterone (DHEA), a major steroid secreted by the adrenal gland which decreases with age after adolescence, is available as a nutritional supplement. DHEA is known to have antiproliferative effects but the mechanism is unclear. In this study using BV-2 cells, a murine microglial cell line, we investigated the effect of DHEA on cell viability and the interaction between DHEA and glucose concentrations in the medium. We showed that DHEA inhibited cell viability and G6PD activity in a dose-dependent manner and that the effect of DHEA on cell viability was inversely associated with glucose concentrations in the medium, i.e. lowered glucose strongly enhanced the inhibition of cell viability by DHEA. DHEA inhibited cell growth by causing cell cycle arrest primarily in the G0--G1 phase, and the effect was more pronounced at zero glucose (no glucose added, G0) than high glucose (4.5 mg/ml of the medium, G4.5). Glucose deprivation also enhanced apoptosis induced by DHEA. At G4.5, DHEA did not induce formation of DNA ladder until it reached 200 microM. However, at G0, 100 microM DHEA was able to induce apoptosis, as evidenced by the formation of DNA ladder, elevation of histone-associated DNA fragmentation and increase in cells positively stained with annexin V-FITC and annexin V-FITC/propidium iodide. The interactions between DHEA and glucose support the contention that DHEA exerts its antiproliferative effects through alteration of glucose metabolism, possibly by inhibition of G6PD activity leading to decreased supply of ribose-5-phosphate for synthesis of DNA and RNA. Although DHEA is only antiproliferative at pharmacological levels, our results indicate that its antiproliferative effect can be enhanced by limiting the supply of glucose such as by energy restriction. In addition, the present study shows that glucose concentration is an important factor to consider when studying the antiproliferative and toxicological effects of DHEA.
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Affiliation(s)
- N C Yang
- Department of Food Science, National Chung-Hsing University, 250 Kuo-Kuang Road, 402 Taichung, Taiwan, ROC
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33
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Scherczinger CA, Hintz JL, Peck BJ, Adamowicz MS, Bourke MT, Coyle HM, Ladd C, Yang NC, Budowle B, Lee HC. Allele frequencies for the CODIS core STR loci in Connecticut populations. J Forensic Sci 2000; 45:938-40. [PMID: 10914605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Affiliation(s)
- C A Scherczinger
- Connecticut State Police Forensic Science Laboratory, Meriden 06451, USA
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34
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Yang NC, Hwang KL, Hung DZ, Wuhh HH, Ho WM. Reliable gas chromatographic-mass spectrometric method combined with a headspace autosampler for isoflurane determination in blood. J Chromatogr B Biomed Sci Appl 2000; 742:277-82. [PMID: 10901132 DOI: 10.1016/s0378-4347(00)00168-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
Isoflurane is a nonflammable, liquid, volatile inhalation anesthetic administered by vaporizing. Although it is now commonly used, fatal cases resulting from its abuse or misuse have been reported. A combined system of a gas chromatograph-mass spectrometer and a headspace autosampler is therefore proposed for the detection of blood isoflurane. This analytic method showed sharp and well separated peaks, and revealed a good linear relationship (r=0.9994) with a function of y = 7.3768x - 0.0222 at concentrations between 18.7 and 299.2 microg/ml. The limits of detection and quantitation of this method were 1.2 and 4.7 microg/ml, respectively. The within- and between-run precision for spiked samples, assessed by the coefficient of variations, ranged from 1.7 to 10.0% and from 4.1 to 12.8%, respectively. The within- and between-run accuracy, assessed by errors from theoretical values, were 2.2-7.8% and 2.4-9.6%, respectively. In addition, practical sample analysis showed a good applicability, with a within-run precision rate of 5.6 to 7.7% and a between-run precision rate of 5.2-10.6%. In summary, the present work presents a valid alternative for blood isoflurane analysis.
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Affiliation(s)
- N C Yang
- Department of Anesthesiology, Taichung Veterans General Hospital, Taiwan
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35
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Hwang KL, Kou SJ, Lu YM, Yang NC. Evaluation of the quality of surgical gloves among four different manufactures. Ann Occup Hyg 1999; 43:275-81. [PMID: 10432871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
A randomized trial was conducted to evaluate the quality of four different brands of surgical gloves in terms of the perforation rate, ventilation, fitness, allergic reaction, elasticity, thickness, powder, and satisfaction. Gloves of four different manufactures which were used by various medical centres were distributed to participants according to a computer-generated randomization table. A structured questionnaire was self-administered by volunteers immediately after the surgical procedure to gather the information from participants, including the demographic data, allergy history, length of use, and variables of quality measures. Two brands, A and D, were significantly inferior to the best manufacture among the four, B, in terms of the ventilation, elasticity, and thickness, odds ratios ranging from 6 to 24, p < 0.05. For the amount of corn starch powder and satisfaction, all three other brands were inferior to brand B, odds ratios ranging from 6 to 44, p < 0.05. Gloves worn longer than 2 hours had a slightly higher perforation rate post procedures (11.5% vs. 2.1%, p = 0.048). The rate of latex allergic reaction was not significantly different between surgeons (8.3%) and the others (6.7%). No difference of the allergic reaction rate was found between subjects with allergy history (7.7%) and those without the history (7.5%). The quality of surgical gloves differs from brand to brand. The government and institutions should take the responsibility of monitoring the quality of surgical gloves in order to provide a safer and more comfortable environment for the surgical personnel and patients.
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36
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Abstract
X-ray diffraction analysis at 1.5 A resolution has confirmed the helical conformation of a de novo designed 18-residue peptide. However, the crystal structure reveals the formation of continuous molecular layers of parallel-packed amphiphilic helices as a result of much more extensive helix-helix interactions than predicted. The crystal packing arrangement, by virtue of distinct antiparallel packing interactions, segregates the polar and apolar surfaces of the helices into discrete and well-defined interfacial regions. An extensive "ridges-into-grooves" interdigitation characterizes the hydrophobic interface, whereas an extensive network of salt bridges and hydrogen bonds dominates the corresponding hydrophilic interface.
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Affiliation(s)
- K S Taylor
- Department of Biochemistry and Molecular Biology, University of Chicago, Illinois 60637, USA
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Kuo ML, Yang NC. Reversion of v-H-ras-transformed NIH 3T3 cells by apigenin through inhibiting mitogen activated protein kinase and its downstream oncogenes. Biochem Biophys Res Commun 1995; 212:767-75. [PMID: 7626110 DOI: 10.1006/bbrc.1995.2035] [Citation(s) in RCA: 105] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Apigenin, a plant flavonoid, induced the reversion of transformed phenotypes of v-H-ras-transformed NIH 3T3 cells at a quite low concentration of 12.5 microM. In the present study, we have examined the components of this Ras-mediated signaling transduction to determine whether they were involved in the apigenin-induced reversion process. Interestingly, the consitutively activated mitogen activated protein kinase (MAPK) in the ras transformant was inhibited significantly and rapidly by 25 microM apigenin within 30 min, and this reduction continued for more than 4 h. Corroborating these observations, expression of the downstream oncogenes c-jun and c-fos was also dramatically reduced during the first 4 h of treatment. We found that the levels of ras protein and mRNA were not affected by 24 h of treatment with apigenin. These findings indicate that apigenin-induced reversion of v-H-ras-transformed NIH 3T3 cells may occur by inhibiting MAPK activity and its downstream oncogenes rather than by affecting the expression of the ras gene.
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Affiliation(s)
- M L Kuo
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Republic of China
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38
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Kuo ML, Lin JK, Huang TS, Yang NC. Reversion of the transformed phenotypes of v-H-ras NIH3T3 cells by flavonoids through attenuating the content of phosphotyrosine. Cancer Lett 1994; 87:91-7. [PMID: 7525047 DOI: 10.1016/0304-3835(94)90414-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Fifteen flavonoids were employed to examine their effects on the morphological changes, foci formation in soft agar and cellular growth in v-H-ras-transformed NIH3T3 cells. The data presented here demonstrated that only three specific flavonoids--apigenin, kaempferol, and genistein--exhibited the reverting effect on the transformed phenotypes of ras-3T3 cells. For example, treatment with 25 microM of these flavonoids could effectively reverse the transformed morphology of ras-3T3 cells into flatter cells with contact inhibition. Colony formation in soft agar was decreased to 0.11%, 0.15%, and 0.35% by 25 microM apigenin, kaempferol, and genistein, respectively, as compared with control (0.92%). It was also found that the proliferation of ras-3T3 cells was significantly inhibited by these compounds in a dose-dependent manner. Finally, two biochemical parameters, the content of phosphotyrosine and cAMP, were examined to see whether affected by these compounds. The results showed the phosphotyrosine content in ras-3T3 cells was dramatically decreased by apigenin and kaempferol, but that was slightly reduced by genistein. By contrast, these three flavonoids all failed to significantly alter the level of cAMP within this transformant. Based on these observations, we suggest that some specific flavonoids are capable of reverting the transforming properties of v-H-ras transformed cells. The possible mechanism of this reversion is not mediated by activating the protein kinase A or its associated pathways, but rather inhibiting tyrosine kinases, subsequently leading to the blockage of p21ras-mediated signal transduction circuitry.
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Affiliation(s)
- M L Kuo
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, R.O.C
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39
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Abstract
Several signalling transduction modulators were used to examine their effects on the morphological changes, foci formation in soft agar and cellular growth in v-H-ras-transformed NIH 3T3 cells. The results from this study showed that specific tyrosine kinase inhibitors (genistein and tyrphostin 23) and cyclic AMP-elevating agents (forskolin and 3-isobutyl-1-methyl-xanthine) could effectively induce differential flat phenotype of v-H-ras transformant at micromolar concentrations. At the same dose range, both signalling modulators also caused a significant suppression of anchorage-independent and cellular growth in the same transformant. By contrast, compound inhibitors such as protein kinase C (staurosporin and H-7), phospholipase A2 (aristolochic acid), phospholipase C (neomycin sulfate) and cyclooxygenase (indomethacin) all did not alter the cellular morphology or foci formation in soft agar, although PKC inhibitors exhibited a slight inhibition on the cellular growth. Based on these observations, we propose that the alterations of protein kinase A or tyrosine kinase-associated signal pathways is necessary and the original cause of the transformation event, but that increase of the activities of protein kinase C, phospholipase C, phospholipase A2 or cyclooxygenase probably is an indirect result of the v-H-ras-mediated transformation.
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Affiliation(s)
- M L Kuo
- Institute of Toxicology, College of Medicine, National Taiwan University, Taipei, Republic of China
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40
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Locke BC, MacInnis JM, Qian S, Gordon JI, Li E, Fleming GR, Yang NC. Fluorescence studies of rat cellular retinol binding protein II produced in Escherichia coli: an analysis of four tryptophan substitution mutants. Biochemistry 1992; 31:2376-83. [PMID: 1540594 DOI: 10.1021/bi00123a024] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Rat intestinal cellular retinol binding protein II (CRBP II) is an abundant 134-residue protein that binds all-trans-retinol which contains 4 tryptophans in positions 9, 89, 107, and 110. Our ability to express CRBP II in Escherichia coli and to construct individual tryptophan substitution mutants by site-directed mutagenesis has provided a useful model system for studying the fluorescence of a multi-tryptophan protein. Each of the four mutant proteins binds all-trans-retinol with high affinity, although their affinities are less than that of the wild-type protein. Steady-state and time-resolved fluorescence analyses of these proteins indicate that W107 is at the hydrophobic binding site, W110 is in a polar environment, and the remaining two tryptophans are in a hydrophobic environment. Time-resolved fluorescence study indicates that excited-state energy transfer occurs from the hydrophobic tryptophans to W110. The Stern-Volmer analysis with acrylamide of these proteins reveals that static quenching occurs in the W9F mutant protein while others do not. The fluorescence of rat intestinal fatty acid binding protein (I-FABP), a related protein of known X-ray structure, was also studied for comparison. The results of these findings, coupled with those derived from NMR studies and molecular graphics, suggest that CRBP II undergoes minor structural changes in all of the mutant proteins. Since these effects may be cumulative on the protein structure and function, any conclusions derived from higher mutants in this family of proteins must be treated with caution.
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Affiliation(s)
- B C Locke
- Department of Chemistry, University of Chicago, Illinois 60637
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41
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Leichner PK, Vriesendorp HM, Hawkins WG, Quadri SM, Yang NC, Stinson RL, Loudenslager DM, Frankel TL, Chen XY, Klein JL. Quantitative SPECT for indium-111-labeled antibodies in the livers of beagle dogs. J Nucl Med 1991; 32:1442-4. [PMID: 2066804] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Results are presented for SPECT computations of liver volumes and 111In-labeled antibody activities in the livers of eight normal beagle dogs. Administered activities ranged from 1 to 2 mCi. SPECT studies were acquired 1 day postinjection using a rotating gamma camera system with elliptical orbits in a 360-degree rotation (128 views, 15 sec/view, 64 x 64 matrices). Uniformity-corrected images were reconstructed by use of the circular harmonic transform algorithm with computer software developed in-house. Liver volumes and activities were computed from transverse slices, 1 pixel (6.25 mm) in thickness. Comparison of SPECT and autopsy data demonstrated that absolute values of percent differences between measured and computed liver volumes ranged from 1.0% to 7.2%. Absolute values of percent differences between autopsy data and computed 111In activities in the liver ranged from 2.3% to 7.5%. These results suggest that quantitative SPECT has the potential of becoming an important tool in clinical trials for determining activities and localization volumes of radiolabeled antibodies directly from radionuclide images.
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Affiliation(s)
- P K Leichner
- Radiation Oncology, Johns Hopkins Oncology Center, Baltimore, Maryland 21231
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42
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Hawkins WG, Yang NC, Leichner PK. Validation of the circular harmonic transform (CHT) algorithm for quantitative SPECT. J Nucl Med 1991; 32:141-50. [PMID: 1988620] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Abstract
The purpose of this study was to validate the use of the circular harmonic transform (CHT) algorithm for quantitative single-photon emission computed tomography (SPECT) with isotopes technetium-99m (99mTc) and indium-111 (111In) under clinically relevant conditions. Phantom studies were the principal tools used. Volumes of fillable organs within a tissue-equivalent anthropomorphic phantom were determined over a wide range (145-1960 ml) to within 6% by using a thresholding technique. Additionally, phantom studies with nonuniform activity distributions were made. These included a background of activity and hot as well as cold lesions. The hot lesion was computed to within 12% (111In) and 7.7% (99mTc), and contrast in the cold lesion was approximately 70% for both isotopes. The CHT algorithm incorporates the energy-distance relation (EDR) which minimizes the degrading effects of attenuation, scatter, collimator blur and poor statistics.
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Affiliation(s)
- W G Hawkins
- Johns Hopkins Oncology Center, Department of Radiation Oncology, Johns Hopkins Medical Institutions, Baltimore, Maryland 21231
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43
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Li E, Qian SJ, Yang NC, d'Avignon A, Gordon JI. 19F nuclear magnetic resonance studies of 6-fluorotryptophan-substituted rat cellular retinol binding protein II produced in Escherichia coli. An analysis of four tryptophan substitution mutants and their interactions with all-trans-retinol. J Biol Chem 1990; 265:11549-54. [PMID: 2195021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Rat cellular retinol binding protein (CRBP II) is a 134-amino acid intracellular protein synthesized in the polarized absorptive cells of the intestine. We have previously used 19F nuclear magnetic resonance (NMR) spectroscopy to survey the structural effects of ligand binding on the apoprotein. For these studies, all 4 Trp residues of rat CRBP II were efficiently labeled with 6-fluorotryptophan (6-F-Trp) by inducing its expression in a tryptophan auxotroph of Escherichia coli. Resonances corresponding to 2 of its Trp residues underwent large downfield shifts upon binding of all-trans-retinol and retinal, while resonances corresponding to the other 2 Trp residues underwent only minor perturbations in chemical shifts. To identify which Trp residues undergo changes in their environment upon ligand binding, we have constructed four CRBP II mutants where Trp9, Trp89, Trp107, or Trp110 have been replaced by another hydrophobic amino acid. By comparing the 19F NMR spectrum of each 6-F-Trp-labeled mutant with that of wild type 6-F-Trp CRBP II, we demonstrate that the 19F resonance corresponding to Trp107 undergoes the largest change in chemical shift upon ligand binding (2.0 ppm downfield). This is consistent with the position of this residue predicted from molecular modeling studies. The 19F resonance corresponding to Trp9 also undergoes a downfield change in chemical shift of 0.5 ppm associated with retinol binding even though it is predicted to be removed from the ligand binding site. By contrast, the resonances assigned to Trp89 and Trp110 undergo only minor perturbations in chemical shifts. These results have allowed us to identify residue-specific probes for evaluating the interactions of all-trans-retinol (and other retinoids) with this intracellular binding protein.
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Affiliation(s)
- E Li
- Department of Medicine, Washington University, St. Louis, Missouri 63110
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44
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Li E, Quian SJ, Nader L, Yang NC, d'Avignon A, Sacchettini JC, Gordon JI. Nuclear magnetic resonance studies of 6-fluorotryptophan-substituted rat cellular retinol-binding protein II produced in Escherichia coli. Analysis of the apoprotein and the holoprotein containing bound all-trans-retinol and all-trans-retinal. J Biol Chem 1989; 264:17041-8. [PMID: 2676998] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
Rat cellular retinol-binding protein II (CRBP II) is a 15.6-kDa intestinal protein which binds all-trans-retinol and all-trans-retinal but not all-trans-retinoic acid. We have previously analyzed the interaction of Escherichia coli-derived rat apoCRBP II with several retinoids using fluorescence spectroscopic techniques. Interpretation of these experiments is complicated, because the protein has 4 tryptophan residues. To further investigate ligand-protein interactions, we have utilized 19F nuclear magnetic resonance (NMR) spectroscopy of CRBP II labeled at its 4 tryptophan residues with 6-fluorotryptophan. Efficient incorporation of 6-fluorotryptophan (93%) was achieved by growing a tryptophan auxotroph of E. coli harboring a prokaryotic expression vector with a full-length rat CRBP II cDNA on defined medium supplemented with the analog. Comparison of the 19F NMR spectra of 6-fluorotryptophan-substituted CRBP II with and without bound all-trans-retinol revealed that resonances corresponding to 2 tryptophan residues (designated WA and WB) undergo large downfield changes in chemical shifts (2.0 and 0.5 ppm, respectively) associated with ligand binding. In contrast, 19F resonances corresponding to two other tryptophan residues (WC and WD) undergo only minor perturbations in chemical shifts. The 19F NMR spectra of 6-fluorotryptophan-substituted CRBP II complexed with all-trans-retinal and all-trans-retinol were very similar, suggesting that the interactions of these two ligands with the protein are similar. Molecular model building, based on the crystalline structures of two homologous proteins was used to predict the positions of the 4 tryptophan residues of CRBP II and to make tentative resonance assignments. The fact that ligand binding produced residue-specific changes in the chemical shifts of resonances in CRBP II suggests that NMR analysis of isotopically labeled retinoid-binding proteins expressed in E. coli will provide an alternate, albeit it complementary, approach to fluorescence spectroscopy for examining the structural consequences of their association with ligand.
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Affiliation(s)
- E Li
- Department of Medicine, Washington University, St. Louis, Missouri 63110
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Li E, Quian SJ, Nader L, Yang NC, d'Avignon A, Sacchettini JC, Gordon JI. Nuclear Magnetic Resonance Studies of 6-Fluorotryptophan-substituted Rat Cellular Retinol-binding Protein II Produced in Escherichia coli. J Biol Chem 1989. [DOI: 10.1016/s0021-9258(18)71456-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Levin MS, Locke B, Yang NC, Li E, Gordon JI. Comparison of the ligand binding properties of two homologous rat apocellular retinol-binding proteins expressed in Escherichia coli. J Biol Chem 1988; 263:17715-23. [PMID: 3053716] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Cellular retinol-binding protein (CRBP) and cellular retinol-binding protein II (CRBP II) are 132-residue cytosolic proteins which have 56% amino acid sequence identity and bind all-trans-retinol as their endogenous ligand. They belong to a family of cytoplasmic proteins which have evolved to bind distinct hydrophobic ligands. Their patterns of tissue-specific and developmental regulation are distinct. We have compared the ligand binding properties of rat apo-CRBP and apo-CRBP II that have been expressed in Escherichia coli. Several observations indicate that the E. coli-derived apoproteins are structurally similar to the native rat proteins: they co-migrate on isoelectric focusing gels; and when complexed with all-trans-retinol, their absorption and excitation/emission spectra are nearly identical to those of the authentic rat holoproteins. Comparative lifetime and acrylamide quenching studies suggest that there are differences in the conformations of apo-CRBP and apo-CRBP II. The interaction of E. coli-derived apo-CRBP and apo-CRBP II with a variety of retinoids was analyzed using spectroscopic techniques. Both apoproteins formed high affinity complexes with all-trans-retinol (K'd approximately 10 nM). In direct binding assays, all-trans-retinal bound to both apoproteins (K'd approximately 50 nM for CRBP; K'd approximately 90 nM for CRBP II). However, all-trans-retinal could displace all-trans-retinol bound to CRBP II but not to CRBP. These observations suggests that there is a specific yet distinct interaction between these two proteins and all-trans-retinal. Apo-CRBP and apo-CRBP II did not demonstrate significant binding to either retinoic acid or methyl retinoate, an uncharged derivative of all-trans-retinoic acid. This indicates that the carboxymethyl group of methyl retinoate cannot be sterically accommodated in their binding pockets and that failure to bind retinoic acid probably is not simply due to the negative charge of its C-15 carboxylate group. Finally, neither all-trans-retinol nor retinoic acid bound to E. coli-derived rat intestinal fatty acid-binding protein, a homologous protein whose tertiary structure is known. Together, the data suggest that these three family members have acquired unique functional capabilities.
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Affiliation(s)
- M S Levin
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
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Leichner PK, Yang NC, Frenkel TL, Loudenslager DM, Hawkins WG, Klein JL, Order SE. Dosimetry and treatment planning for 90Y-labeled antiferritin in hepatoma. Int J Radiat Oncol Biol Phys 1988; 14:1033-42. [PMID: 2834309 DOI: 10.1016/0360-3016(88)90029-6] [Citation(s) in RCA: 51] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Radiation absorbed-dose estimates and treatment planning are reported for 11 patients with hepatoma who were administered 90Y-labeled polyclonal antiferritin IgG for therapy in a Phase 1-2 trial. Dosimetric studies included quantitation of the localization and clearance of 111In-labeled antiferritin IgG in tumor and normal tissues and computer-assisted tumor and normal liver volumetrics from X ray CT scans. For the group of patients studied, hepatoma volumes at the time of treatment ranged from 135 to 3442 cm3. Quantitative 111In antiferritin imaging prior to and following 600 or 900 cGy of external-beam irradiation of the primary tumor demonstrated that tumor uptake increased 1.1 to 5.8-fold (mean 2.8) following external beam. In contrast, changes in uptake of radiolabeled antiferritin in normal liver ranged from 0.35 to 2.1-fold (mean 0.93) after external irradiation. Administered activities of 90Y antiferritin ranged from 8 to 37 mCi and were dependent on tumor volume and tumor localization of radiolabeled antiferritin. Following external-beam irradiation, tumor dose rates achieved with 90Y antiferritin ranged from 10 to 20 cGy/hr and normal liver dose rates from 1.1 to 5.7 cGy/h. The corresponding absorbed dose in hepatomas ranged from 900 to 2150 cGy and in normal liver from 80 to 650 cGy. After external-beam irradiation, tumor and normal liver uptake of 90Y antiferritin was consistent with that of 131I antiferritin.
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Affiliation(s)
- P K Leichner
- Department of Radiation Oncology, Johns Hopkins Medical Institutions, Baltimore, MD 21205
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Hawkins WG, Leichner PK, Yang NC. The circular harmonic transform for SPECT reconstruction and boundary conditions on the Fourier transform of the sinogram. IEEE Trans Med Imaging 1988; 7:135-138. [PMID: 18230462 DOI: 10.1109/42.3940] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The circular harmonic transform (CHT) solution of the exponential Randon transform (ERT) is applied to single-photon emission computed tomography (SPECT) for uniform attenuation within a convex boundary. An important special case also considered is the linear (unattenuated) Radon transform (LRT). The solution is on the form of an orthogonal function expansion matched to projections that are in parallel-ray geometry. This property allows for efficient and accurate processing of the projections with fast Fourier transform (FFT) without interpolation or beam matching. The algorithm is optimized by the use of boundary conditions on the 2-D Fourier transform of the sinogram. These boundary conditions imply that the signal energy of the sinogram is concentrated in well-defined sectors in transform space. The angle defining the sectors depends in a direct way on the radius of the field view. These results are also obtained for fan-beam geometry and the linear Radon transform (the Fourier-Chebyshev transform of the sinogram) to demonstrate that the boundary conditions are a more general property of the Radon transform and a not a property unique to rectangular coordinates.
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Li E, Locke B, Yang NC, Ong DE, Gordon JI. Characterization of rat cellular retinol-binding protein II expressed in Escherichia coli. J Biol Chem 1987; 262:13773-9. [PMID: 3308883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Rat cellular retinol-binding protein II (CRBP II) is a small (15.6 kDa) intracellular protein that binds all-trans-retinol. In the adult rat, expression of the CRBP II gene is essentially limited to the small intestinal lining cells (enterocytes), suggesting that CRBP II may be uniquely adapted for intestinal metabolism of newly absorbed retinol. Functional and structural analysis of this protein has been hampered by difficulties in freeing rat intestinal CRBP II from its ligand without denaturation. To circumvent this problem, we have obtained efficient expression of rat apoCRBP II in Escherichia coli. The purified E. coli-derived apoprotein, when complexed with all-trans-retinol, demonstrates fluorescence excitation-emission spectra and absorption spectra indistinguishable from that of CRBP II-retinol isolated from rat intestine. Quantitative ligand binding studies were performed by monitoring either the fluorescence of bound retinol or the quenching of protein fluorescence. They revealed that E. coli-derived CRBP II binds retinol tightly (the apparent dissociation constant is estimated to be 10(-7)-10(-8) M), with a stoichiometry of 1:1. Fluorescence quenching studies used acrylamide as a probe for the exposure of the 4 tryptophan residues to solvent. The results indicate that although there is heterogeneity in the exposure of these 4 tryptophan residues to solvent, they are situated in a relatively nonpolar environment. These studies suggest that E. coli-derived apoCRBP II will serve as a useful model for studying retinol-protein interactions.
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Affiliation(s)
- E Li
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri 63110
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