Angiotensin-converting enzyme gene I/D polymorphism in Pakistani ...

African Journals Online (AJOL)

hope&shola

two were the cases of antiphospholipid syndrome. Parsa et al. (2002) conducted an association of 3 polymor- phisms in angiotensin-converting enzyme including I/D polymorphism and 2 polymorphisms were associated with systemic lupus erythematosus and Lupus Nephritis among non-Caucasians that includes Hispanic, ...

Polymorphisms in xenobiotic metabolizing enzymes and diet influence colorectal adenoma risk.

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Northwood, Emma L; Elliott, Faye; Forman, David; Barrett, Jennifer H; Wilkie, Murray J V; Carey, Francis A; Steele, Robert J C; Wolf, Roland; Bishop, Timothy; Smith, Gillian

2010-05-01

We have earlier shown that diet and xenobiotic metabolizing enzyme genotypes influence colorectal cancer risk, and now investigate whether similar associations are seen in patients with premalignant colorectal adenomas (CRA), recruited during the pilot phase of the Scottish Bowel Screening Programme. Nineteen polymorphisms in 13 genes [cytochrome P450 (P450), glutathione S-transferase (GST), N-acetyl transferase, quinone reductase (NQ01) and microsomal epoxide hydrolase (EPHX1) genes] were genotyped using multiplex PCR or Taqman-based allelic discrimination assays and analyzed in conjunction with diet, assessed by food frequency questionnaire, in a case-control study [317 CRA cases (308 cases genotyped), 296 controls]. Findings significant at a nominal 5% level are reported. CRA risk was inversely associated with fruit (P=0.02, test for trend) and vegetable (P=0.001, test for trend) consumption. P450 CYP2C9*3 heterozygotes had reduced CRA risk compared with homozygotes for the reference allele [odds ratio (OR): 0.60; 95% confidence interval (CI): 0.36-0.99], whereas CYP2D6*4 homozygotes (OR: 2.72; 95% CI: 1.18-6.27) and GSTM1 'null' individuals (OR: 1.43; 95% CI: 1.04-1.98) were at increased risk. The protective effect of fruit consumption was confined to GSTP1 (Ala114Val) reference allele homozygotes (OR: 0.49; 95% CI: 0.34-0.71, P=0.03 for interaction). CRA risk was not associated with meat consumption, although a significant interaction between red meat consumption and EPHX1 (His139Arg) genotype was noted (P=0.02 for interaction). We report the novel associations between P450 genotype and CRA risk, and highlight the risk association with GSTM1 genotype, common to our CRA and cancer case-control series. In addition, we report a novel modifying influence of GSTP1 genotype on dietary chemoprevention. These novel findings require independent confirmation.

Angiotensin converting enzyme (ACE D/I) polymorphism and its ...

African Journals Online (AJOL)

Hepatitis C virus (HCV) infection is a global health problem in Egypt and causes different liver disease spectrum. Evidence indicates that angiotensin I converting enzyme (ACE) gene polymorphism may play a role in determining disease progression. We aimed to determine the association of ACE gene I/D polymorphism ...

Genotype of metabolic enzymes and the benefit of tamoxifen in postmenopausal breast cancer patients

International Nuclear Information System (INIS)

Wegman, Pia; Vainikka, Linda; Stål, Olle; Nordenskjöld, Bo; Skoog, Lambert; Rutqvist, Lars-Erik; Wingren, Sten

2005-01-01

Tamoxifen is widely used as endocrine therapy for oestrogen-receptor-positive breast cancer. However, many of these patients experience recurrence despite tamoxifen therapy by incompletely understood mechanisms. In the present report we propose that tamoxifen resistance may be due to differences in activity of metabolic enzymes as a result of genetic polymorphism. Cytochrome P450 2D6 (CYP2D6) and sulfotransferase 1A1 (SULT1A1) are polymorphic and are involved in the metabolism of tamoxifen. The CYP2D6*4 and SULT1A1*2 genotypes result in decreased enzyme activity. We therefore investigated the genotypes of CYP2D6 and SULT1A1 in 226 breast cancer patients participating in a trial of adjuvant tamoxifen treatment in order to validate the benefit from the therapy. The patients were genotyped using PCR followed by cleavage with restriction enzymes. Carriers of the CYP2D6*4 allele demonstrated a decreased risk of recurrence when treated with tamoxifen (relative risk = 0.28, 95% confidence interval = 0.11–0.74, P = 0.0089). A similar pattern was seen among the SULT1A1*1 homozygotes (relative risk = 0.48, 95% confidence interval = 0.21–1.12, P = 0.074). The combination of CYP2D6*4 and/or SULT1A1*1/*1 genotypes comprised 60% of the patients and showed a 62% decreased risk of distant recurrence with tamoxifen (relative risk = 0.38, 95% confidence interval = 0.19–0.74, P = 0.0041). The present study suggests that genotype of metabolic enzymes might be useful as a guide for adjuvant endocrine treatment of postmenopausal breast cancer patients. However, results are in contradiction to prior hypotheses and the present sample size is relatively small. Findings therefore need to be confirmed in a larger cohort

Vision Issues and Space Flight: Evaluation of One-Carbon Metabolism Polymorphisms

Science.gov (United States)

Smith, Scott M.; Gregory, Jesse F.; Zeisel, Steven; Ueland, Per; Gibson, C. R.; Mader, Thomas; Kinchen, Jason; Ploutz-Snyder, Robert; Zwart, Sara R.

2015-01-01

Intermediates of the one-carbon metabolic pathway are altered in astronauts who experience vision-related issues during and after space flight. Serum concentrations of homocysteine, cystathionine, 2-methylcitric acid, and methylmalonic acid were higher in astronauts with ophthalmic changes than in those without (Zwart et al., J Nutr, 2012). These differences existed before, during, and after flight. Potential confounding factors did not explain the differences. Genetic polymorphisms could contribute to these differences, and could help explain why crewmembers on the same mission do not all have ophthalmic issues, despite the same environmental factors (e.g., microgravity, exercise, diet). A follow-up study was conducted to evaluate 5 polymorphisms of enzymes in the one-carbon pathway, and to evaluate how these relate to vision and other ophthalmic changes after flight. Preliminary evaluations of the genetic data indicate that all of the crewmembers with the MTRR GG genotype had vision issues to one degree or another. However, not everyone who had vision issues had this genetic polymorphism, so the situation is more complex than the involvement of this single polymorphism. Metabolomic and further data analyses are underway to clarify these findings, but the preliminary assessments are promising.

Genetic polymorphisms in 5-Fluorouracil-related enzymes predict pathologic response after neoadjuvant chemoradiation for rectal cancer.

Science.gov (United States)

Nelson, Bailey; Carter, Jane V; Eichenberger, Maurice R; Netz, Uri; Galandiuk, Susan

2016-11-01

Many patients with rectal cancer undergo preoperative neoadjuvant chemoradiation, with approximately 70% exhibiting pathologic downstaging in response to treatment. Currently, there is no accurate test to predict patients who are likely to be complete responders to therapy. 5-Fluorouracil is used regularly in the neoadjuvant treatment of rectal cancer. Genetic polymorphisms affect the activity of thymidylate synthase, an enzyme involved in 5-Fluorouracil metabolism, which may account for observed differences in response to neoadjuvant treatment between patients. Detection of genetic polymorphisms might identify patients who are likely to have a complete response to neoadjuvant therapy and perhaps allow them to avoid operation. DNA was isolated from whole blood taken from patients with newly diagnosed rectal cancer who received neoadjuvant therapy (n = 50). Response to therapy was calculated with a tumor regression score based on histology from the time of operation. Polymerase chain reaction was performed targeting the promoter region of thymidylate synthase. Polymerase chain reaction products were separated using electrophoresis to determine whether patients were homozygous for a double-tandem repeat (2R), a triple-tandem repeat (3R), or were heterozygous (2R/3R). A single nucleotide polymorphism, 3G or 3C, also may be present in the second repeat unit of the triple-tandem repeat allele. Restriction fragment length polymorphism assays were performed in patients with at least one 3R allele using HaeIII. Patients with at least 1 thymidylate synthase 3G allele were more likely to have a complete or partial pathologic response to 5-Fluorouracil neoadjuvant therapy (odds ratio 10.4; 95% confidence interval, 1.3-81.6; P = .01) than those without at least one 3G allele. Identification of rectal cancer patients with specific genetic polymorphisms in enzymes involved in 5-Fluorouracil metabolism seems to predict the likelihood of complete or partial pathologic response

Polymorphisms in folate-metabolizing enzymes and response to 5-fluorouracil among patients with stage II or III rectal cancer (INT-0144; SWOG 9304).

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Ulrich, Cornelia M; Rankin, Cathryn; Toriola, Adetunji T; Makar, Karen W; Altug-Teber, Özge; Benedetti, Jacqueline K; Holmes, Rebecca S; Smalley, Stephen R; Blanke, Charles D; Lenz, Heinz-Josef

2014-11-01

Recurrence and toxicity occur commonly among patients with rectal cancer who are treated with 5-fluorouracil (5-FU). The authors hypothesized that genetic variation in folate-metabolizing genes could play a role in interindividual variability. The objective of the current study was to evaluate the associations between genetic variants in folate-metabolizing genes and clinical outcomes among patients with rectal cancer treated with 5-FU. The authors investigated 8 functionally significant polymorphisms in 6 genes (methylenetetrahydrofolate reductase [MTHFR] [C677T, A1298C], SLC19A1 [G80A], SHMT1 [C1420T], dihydrofolate reductase [DHFR] [Del19bp], TS 1494del,and TSER) involved in folate metabolism in 745 patients with TNM stage II or III rectal cancer enrolled in a phase 3 adjuvant clinical trial of 3 regimens of 5-FU and radiotherapy (INT-0144 and SWOG 9304). There were no statistically significant associations noted between polymorphisms in any of the genes and overall survival, disease-free survival (DFS), and toxicity in the overall analyses. Nevertheless, there was a trend toward worse DFS among patients with the variant allele of MTHFR C677T compared with wild-type, particularly in treatment arm 2, in which patients with the MTHFR C677T TT genotype had worse overall survival (hazards ratio, 1.76; 95% confidence interval, 1.06-2.93 [P = .03]) and DFS (hazards ratio, 1.84; 95% confidence interval, 1.12-3.03 [P = .02]) compared with those with homozygous wild-type. In addition, there was a trend toward reduced hematological toxicity among patients with variants of SLC19A1 G80A in treatment arm 1 (P for trend, .06) and reduced esophagitis/stomatitis noted among patients with variants of TSER in treatment arm 3 (P for trend, .06). Genetic variability in folate-metabolizing enzymes was found to be associated only to a limited degree with clinical outcomes among patients with rectal cancer treated with 5-FU. © 2014 American Cancer Society.

Association of ghrelin polymorphisms with metabolic syndrome in Han Nationality Chinese.

Science.gov (United States)

Xu, Ling-Ling; Xiang, Hong-Ding; Qiu, Chang-Chun; Xu, Qun

2008-06-01

To investigate the association of ghrelin gene polymorphisms with metabolic syndrome in Han Nationality Chinese. A total of 240 patients with metabolic syndrome and 427 adults aged above forty years were recruited. Genotypes were determined by polymerase chain reaction and restriction fragment length polymorphism analysis. The allelic frequency of the Leu72Met polymorphism was 17.3% in the patient group and 11.9% in the control group (chi2 = 7.36, P = 0.007). Metabolic syndrome was more prevalent among carriers of the Met72 variant (43.8 vs 33.1%, age- and sex-adjusted odds ratio = 1.57, P = 0.01). No Arg51Gln variants were found in our study subjects. Rather than being associated with its individual components, Leu72Met polymorphism is associated with metabolic syndrome in the Han Nationality Chinese. Arg51Gln polymorphism is rare in the Han Nationality Chinese.

Voltage-gated sodium channel polymorphism and metabolic resistance in pyrethroid-resistant Aedes aegypti from Brazil.

Science.gov (United States)

Martins, Ademir Jesus; Lins, Rachel Mazzei Moura de Andrade; Linss, Jutta Gerlinde Birgitt; Peixoto, Alexandre Afranio; Valle, Denise

2009-07-01

The nature of pyrethroid resistance in Aedes aegypti Brazilian populations was investigated. Quantification of enzymes related to metabolic resistance in two distinct populations, located in the Northeast and Southeast regions, revealed increases in Glutathione-S-transferase (GST) and Esterase levels. Additionally, polymorphism was found in the IIS6 region of Ae. aegypti voltage-gated sodium channel (AaNa(V)), the pyrethroid target site. Sequences were classified in two haplotype groups, A and B, according to the size of the intron in that region. Rockefeller, a susceptible control lineage, contains only B sequences. In field populations, some A sequences present a substitution in the 1011 site (Ile/Met). When resistant and susceptible individuals were compared, the frequency of both A (with the Met mutation) and B sequences were slightly increased in resistant specimens. The involvement of the AaNa(V) polymorphism in pyrethroid resistance and the metabolic mechanisms that lead to potential cross-resistance between organophosphate and pyrethroids are discussed.

Induction of drug-metabolizing enzymes: mechanisms and consequences

Energy Technology Data Exchange (ETDEWEB)

Okey, A.B.; Roberts, E.A.; Harper, P.A.; Denison, M.S.

1986-04-01

The activity of many enzymes that carry out biotransformation of drugs and environmental chemicals can be substantially increased by prior exposure of humans or animals to a wide variety of foreign chemicals. Increased enzyme activity is due to true enzyme induction mediated by increased synthesis of mRNAs which code for specific drug-metabolizing enzymes. Several species of cytochrome P-450 are inducible as are certain conjugating enzymes such as glutathione S-transferases, glucuronosyl transferases, and epoxide hydrolases. Induction of drug-metabolizing enzymes has been shown in several instances to alter the efficacy of some therapeutic agents. Induction of various species of cytochrome P-450 also is known to increase the rate at which potentially toxic reactive metabolic intermediates are formed from drugs or environmental chemicals. Overall, however, induction of drug-metabolizing enzymes appears to be a beneficial adaptive response for organisms living in a ''chemically-hostile'' world.48 references.

[Interaction between CYP450 enzymes and metabolism of traditional Chinese medicine as well as enzyme activity assay].

Science.gov (United States)

Lu, Tu-lin; Su, Lian-lin; Ji, De; Gu, Wei; Mao, Chun-qin

2015-09-01

Drugs are exogenous compounds for human bodies, and will be metabolized by many enzymes after administration. CYP450 enzyme, as a major metabolic enzyme, is an important phase I drug metabolizing enzyme. In human bodies, about 75% of drug metabolism is conducted by CYP450 enzymes, and CYP450 enzymes is the key factor for drug interactions between traditional Chinese medicine( TCM) -TCM, TCM-medicine and other drug combination. In order to make clear the interaction between metabolic enzymes and TCM metabolism, we generally chose the enzymatic activity as an evaluation index. That is to say, the enhancement or reduction of CYP450 enzyme activity was used to infer the inducing or inhibitory effect of active ingredients and extracts of traditional Chinese medicine on enzymes. At present, the common method for measuring metabolic enzyme activity is Cocktail probe drugs, and it is the key to select the suitable probe substrates. This is of great significance for study drug's absorption, distribution, metabolism and excretion (ADME) process in organisms. The study focuses on the interaction between TCMs, active ingredients, herbal extracts, cocktail probe substrates as well as CYP450 enzymes, in order to guide future studies.

Vitamins B2 and B6 and Genetic Polymorphisms Related to One-Carbon Metabolism as Risk Factors for Gastric Adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition

NARCIS (Netherlands)

Eussen, Simone J. P. M.; Vollset, Stein Emil; Hustad, Steinar; Midttun, Oivind; Meyer, Klaus; Fredriksen, Ase; Ueland, Per Magne; Jenab, Mazda; Slimani, Nadia; Ferrari, Pietro; Agudo, Antonio; Sala, Nuria; Capella, Gabriel; Del Giudice, Giuseppe; Palli, Domenico; Boeing, Heiner; Weikert, Cornelia; Bueno-de-Mesquita, H. Bas; Buechner, Frederike L.; Carneiro, Fatima; Berrino, Franco; Vineis, Paolo; Tumino, Rosario; Panico, Salvatore; Berglund, Goran; Manjer, Jonas; Stenling, Roger; Hallmans, Goeran; Martinez, Carmen; Arrizola, Larraitz; Barricarte, Aurelio; Navarro, Carmen; Rodriguez, Laudina; Bingham, Sheila; Linseisen, Jakob; Kaaks, Rudolf; Overvad, Kim; Tjonneland, Anne; Peeters, Petra H. M.; Numans, Mattijs E.; Clavel-Chapelon, Francoise; Boutron-Ruault, Marie-Christine; Morois, Sophie; Trichopoulou, Antonia; Lund, Eiliv; Plebani, Mario; Riboli, Elio; Gonzalez, Carlos A.

B vitamins and polymorphisms in genes coding for enzymes involved in one-carbon metabolism may affect DNA synthesis and methylation and thereby be implicated in carcinogenesis. Previous data on vitamins B2 and B6 and genetic polymorphisms other than those involving MTHFR as risk factors for gastric

21 CFR 862.3360 - Drug metabolizing enzyme genotyping system.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Drug metabolizing enzyme genotyping system. 862... Test Systems § 862.3360 Drug metabolizing enzyme genotyping system. (a) Identification. A drug metabolizing enzyme genotyping system is a device intended for use in testing deoxyribonucleic acid (DNA...

Life-history evolution and the microevolution of intermediary metabolism: activities of lipid-metabolizing enzymes in life-history morphs of a wing-dimorphic cricket.

Science.gov (United States)

Zera, Anthony J; Zhao, Zhangwu

2003-03-01

Although a considerable amount of information is available on the ecology, genetics, and physiology of life-history traits, much more limited data are available on the biochemical and genetic correlates of life-history variation within species. Specific activities of five enzymes of lipid biosynthesis and two enzymes of amino acid catabolism were compared among lines selected for flight-capable (LW[f]) versus flightless (SW) morphs of the cricket Gryllus firmus. These morphs, which exist in natural populations, differ genetically in ovarian growth (100-400% higher in SW) and aspects of flight capability including the size of wings and flight muscles, and the concentration of triglyceride flight fuel (40% greater in LW[f]). Consistently higher activity of each enzyme in LW(f) versus SW-selected lines, and strong co-segregation between morph and enzyme activity, demonstrated genetically based co-variance between wing morph and enzyme activity. Developmental profiles of enzyme activities strongly paralleled profiles of triglyceride accumulation during adulthood and previous measures of in vivo lipid biosynthesis. These data strongly imply that genetically based elevation in activities of lipogenic enzymes, and enzymes controlling the conversion of amino acids into lipids, is an important cause underlying the elevated accumulation of triglyceride in the LW(f) morph, a key biochemical component of the trade-off between elevated early fecundity and flight capability. Global changes in lipid and amino-acid metabolism appear to have resulted from microevolutionary alteration of regulators of metabolism. Finally, strong genotype x environment (diet) interactions were observed for most enzyme activities. Future progress in understanding the functional causes of life-history evolution requires a more detailed synthesis of the fields of life-history evolution and metabolic biochemistry. Wing polymorphism is a powerful experimental model in such integrative studies.

Polymorphism of alcohol metabolizing gene ADH3 predisposes to development of alcoholic pancreatitis in North Indian population

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Divya eSingh

2015-12-01

Full Text Available Background and aim- Genetic factors regulating alcohol metabolism could predispose in developing alcoholic pancreatitis (ACP. Studies revealed that alcohol could be metabolized by both ways, oxidative and non-oxidative. The main oxidative pathway includes alcohol dehydrogenase (ADH, aldehyde dehydrogenase (ALDH and cytochrome P450 enzyme. We investigated whether polymorphism in these alcohol metabolizing enzyme genes could be associated with alcoholic pancreatitis and is the purpose of our study. Method- Patients with alcoholic pancreatitis (ACP (n=72, tropical calcific pancreatitis (TCP (n=75, alcoholic controls (AC (n=40 and healthy controls (HC (n=100 were included in the study. Blood samples were collected from the subjects in EDTA coated vials. DNA was extracted and genotyping for ADH3, ALDH2 and CYP2E1 was done by PCR-RFLP (polymerase chain reaction- restriction fragment length polymorphism. The products were analyzed by gel electrophoresis. Result- The frequency distribution of ADH3*1/*1 genotype was significantly higher in ACP group (59.7% compared with TCP (38.7%, HC (42% and AC (37.5% and was found to be associated with increased risk of alcoholic pancreatitis. There was no statistically significant difference between the frequency distribution of ADH3*1/*1, ADH3*1/*2 and ADH3*2/*2 genotype between TCP and HC and healthy alcoholics. ALDH2 gene was monomorphic in our population, and the frequencies for CYP2E1 intron 6 Dra I polymorphism were comparable in all four groups. Conclusion- This study shows that carriers of ADH3*1/*1 individuals consuming alcohol are at higher risk for alcoholic pancreatitis than those with other genotypes such as ADH3*1/*2 and ADH3*2/*2.

Implication of Xenobiotic Metabolizing Enzyme gene (CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 Polymorphisms in Breast Carcinoma

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Gabbouj Sallouha

2008-04-01

Full Text Available Abstract Background Xenobiotic Metabolizing Enzymes (XMEs contribute to the detoxification of numerous cancer therapy-induced products. This study investigated the susceptibility and prognostic implications of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene polymorphisms in breast carcinoma patients. Methods The authors used polymerase chain reaction and restriction enzyme digestion to characterize the variation of the CYP2E1, CYP2C19, CYP2D6, mEH and NAT2 gene in a total of 560 unrelated subjects (246 controls and 314 patients. Results The mEH (C/C mutant and the NAT2 slow acetylator genotypes were significantly associated with breast carcinoma risk (p = 0.02; p = 0.01, respectively. For NAT2 the association was more pronounced among postmenopausal patients (p = 0.006. A significant association was found between CYP2D6 (G/G wild type and breast carcinoma risk only in postmenopausal patients (p = 0.04. Association studies of genetic markers with the rates of breast carcinoma specific overall survival (OVS and the disease-free survival (DFS revealed among all breast carcinoma patients no association to DFS but significant differences in OVS only with the mEH gene polymorphisms (p = 0.02. In addition, the mEH wild genotype showed a significant association with decreased OVS in patients with axillary lymph node-negative patients (p = 0.03 and with decreasesd DFS in patients with axillary lymph node-positive patients (p = 0.001. However, the NAT2 intermediate acetylator genotype was associated with decreased DFS in axillary lymph node-negative patients. Conclusion The present study may prove that polymorphisms of some XME genes may predict the onset of breast carcinoma as well as survival after treatment.

Network analysis of metabolic enzyme evolution in Escherichia coli

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Kraulis Per

2004-02-01

Full Text Available Abstract Background The two most common models for the evolution of metabolism are the patchwork evolution model, where enzymes are thought to diverge from broad to narrow substrate specificity, and the retrograde evolution model, according to which enzymes evolve in response to substrate depletion. Analysis of the distribution of homologous enzyme pairs in the metabolic network can shed light on the respective importance of the two models. We here investigate the evolution of the metabolism in E. coli viewed as a single network using EcoCyc. Results Sequence comparison between all enzyme pairs was performed and the minimal path length (MPL between all enzyme pairs was determined. We find a strong over-representation of homologous enzymes at MPL 1. We show that the functionally similar and functionally undetermined enzyme pairs are responsible for most of the over-representation of homologous enzyme pairs at MPL 1. Conclusions The retrograde evolution model predicts that homologous enzymes pairs are at short metabolic distances from each other. In general agreement with previous studies we find that homologous enzymes occur close to each other in the network more often than expected by chance, which lends some support to the retrograde evolution model. However, we show that the homologous enzyme pairs which may have evolved through retrograde evolution, namely the pairs that are functionally dissimilar, show a weaker over-representation at MPL 1 than the functionally similar enzyme pairs. Our study indicates that, while the retrograde evolution model may have played a small part, the patchwork evolution model is the predominant process of metabolic enzyme evolution.

Angiotensin-I converting enzyme gene and I/D polymorphism ...

Indian Academy of Sciences (India)

Angiotensin-I converting enzyme gene and I/D polymorphism distribution in the Greek population and a comparison with other European populations. Sekerli Eleni Katsanidis Dimitrios Papadopoulou Vaya Makedou Areti Vavatsi Norma Gatzola Magdalini. Research Note Volume 87 Issue 1 April 2008 pp 91-93 ...

Alcohol consumption, alcohol dehydrogenase 3 polymorphism, and colorectal adenomas

NARCIS (Netherlands)

Tiemersma, E.W.; Wark, P.A.; Ocké, M.C.; Bunschoten, A.; Otten, M.H.; Kok, F.J.; Kampman, E.

2003-01-01

Alcohol is a probable risk factor with regard to colorectal neoplasm and is metabolized to the carcinogen acetaldehyde by the genetically polymorphic alcohol dehydrogenase 3 (ADH3) enzyme. We evaluated whether the association between alcohol and colorectal adenomas is modified by ADH3 polymorphism.

Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals

Energy Technology Data Exchange (ETDEWEB)

Goodrich, Jaclyn M.; Wang, Yi [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Gillespie, Brenda [Department of Biostatistics, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Werner, Robert [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Department of Physical Medicine and Rehabilitation, University of Michigan, 325 E. Eisenhower Parkway Suite 100, Ann Arbor, MI 48108 (United States); Franzblau, Alfred [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States); Basu, Niladri, E-mail: niladri@umich.edu [Department of Environmental Health Sciences, University of Michigan School of Public Health, 1415 Washington Heights, Ann Arbor, MI 48109 (United States)

2011-12-15

Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione s-transferase, and selenoprotein genes underlie inter-individual differences in mercury body burden as assessed by analytical mercury measurement in urine and hair, biomarkers of elemental mercury and methylmercury, respectively. Urine and hair samples were collected from a population of dental professionals (n = 515), and total mercury content was measured. Average urine (1.06 {+-} 1.24 ug/L) and hair mercury levels (0.49 {+-} 0.63 ug/g) were similar to national U.S. population averages. Taqman assays were used to genotype DNA from buccal swab samples at 15 polymorphic sites in genes implicated in mercury metabolism. Linear regression modeling assessed the ability of polymorphisms to modify the relationship between mercury biomarker levels and exposure sources (e.g., amalgams, fish consumption). Five polymorphisms were significantly associated with urine mercury levels (GSTT1 deletion), hair mercury levels (GSTP1-105, GSTP1-114, GSS 5 Prime ), or both (SEPP1 3 Prime UTR). Overall, this study suggests that polymorphisms in selenoproteins and glutathione-related genes may influence elimination of mercury in the urine and hair or mercury retention following exposures to elemental mercury (via dental amalgams) and methylmercury (via fish consumption). -- Highlights: Black-Right-Pointing-Pointer We explore the influence of 15 polymorphisms on urine and hair Hg levels. Black-Right-Pointing-Pointer Urine and hair Hg levels in dental professionals were similar to the US population. Black-Right-Pointing-Pointer GSTT1 and SEPP1 polymorphisms associated with urine Hg levels. Black

Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals

International Nuclear Information System (INIS)

Goodrich, Jaclyn M.; Wang, Yi; Gillespie, Brenda; Werner, Robert; Franzblau, Alfred; Basu, Niladri

2011-01-01

Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione s-transferase, and selenoprotein genes underlie inter-individual differences in mercury body burden as assessed by analytical mercury measurement in urine and hair, biomarkers of elemental mercury and methylmercury, respectively. Urine and hair samples were collected from a population of dental professionals (n = 515), and total mercury content was measured. Average urine (1.06 ± 1.24 ug/L) and hair mercury levels (0.49 ± 0.63 ug/g) were similar to national U.S. population averages. Taqman assays were used to genotype DNA from buccal swab samples at 15 polymorphic sites in genes implicated in mercury metabolism. Linear regression modeling assessed the ability of polymorphisms to modify the relationship between mercury biomarker levels and exposure sources (e.g., amalgams, fish consumption). Five polymorphisms were significantly associated with urine mercury levels (GSTT1 deletion), hair mercury levels (GSTP1-105, GSTP1-114, GSS 5′), or both (SEPP1 3′UTR). Overall, this study suggests that polymorphisms in selenoproteins and glutathione-related genes may influence elimination of mercury in the urine and hair or mercury retention following exposures to elemental mercury (via dental amalgams) and methylmercury (via fish consumption). -- Highlights: ► We explore the influence of 15 polymorphisms on urine and hair Hg levels. ► Urine and hair Hg levels in dental professionals were similar to the US population. ► GSTT1 and SEPP1 polymorphisms associated with urine Hg levels. ► Accumulation of Hg in hair following exposure from fish was modified by genotype. ► GSTP1, GSS

Polymorphisms of xenobiotic metabolizing enzymes in bladder cancer patients of the Semmelweis University Budapest, Hungary.

Science.gov (United States)

Ebbinghaus, Dörte; Bánfi, Gergely; Selinski, Silvia; Blaszkewicz, Meinolf; Bürger, Hannah; Hengstler, Jan G; Nyirády, Péter; Golka, Klaus

2017-01-01

Polymorphic xenobiotic metabolizing enzymes such as N-acetyltransferase 2 (NAT2) or glutathione S-transferase M1 (GSTM1) are known to modulate bladder cancer risk. As no apparent data were available from Hungary, a former member of the eastern European economic organization, a study was performed in Budapest. In total, 182 bladder cancer cases and 78 cancer-free controls were investigated by questionnaire. Genotypes of NAT2, GSTM1, GSTT1, rs1058396 and rs17674580 were determined by standard methods. Current smokers' crude odds ratio (OR) (3.43) and former smokers crude OR (2.36) displayed a significantly increased bladder cancer risk. The risk rose by a factor of 1.56 per 10 pack years. Exposure to fumes was associated with an elevated bladder cancer risk (23% cases, 13% controls). Sixty-four % of the cases and 59% of controls were slow NAT2 acetylators. It was not possible to establish a particular impact of NAT2*6A and *7B genotypes (15 cases, 8%, 5 controls, 7%). GSTT1 exerted no marked influence on bladder cancer (negative 21% cases vs. 22% controls). The portion of GSTM1 negative bladder cancer patients was increased (63% cases vs. 54% controls). The SLC14A1 SNPs rs1058396[AG/GG] and the nearby rs17674580[CT/TT] occurred more frequently in cases (79% and 68%) than controls (77% and 55%). The portion of GSTM1 negative bladder cancer patients is comparable with portions reported from other industrialized areas like Lutherstadt Wittenberg/Germany (58%), Dortmund/Germany (70%), Brescia/Italy (66%) or an occupational case-control series in Germany (56%). Data indicate that GSTM1 is a susceptibility factor for environmentally triggered bladder cancer rather than for smoking-mediated bladder cancer.

Interplay of drug metabolizing enzymes with cellular transporters.

Science.gov (United States)

Böhmdorfer, Michaela; Maier-Salamon, Alexandra; Riha, Juliane; Brenner, Stefan; Höferl, Martina; Jäger, Walter

2014-11-01

Many endogenous and xenobiotic substances and their metabolites are substrates for drug metabolizing enzymes and cellular transporters. These proteins may not only contribute to bioavailability of molecules but also to uptake into organs and, consequently, to overall elimination. The coordinated action of uptake transporters, metabolizing enzymes, and efflux pumps, therefore, is a precondition for detoxification and elimination of drugs. As the understanding of the underlying mechanisms is important to predict alterations in drug disposal, adverse drug reactions and, finally, drug-drug interactions, this review illustrates the interplay between selected uptake/efflux transporters and phase I/II metabolizing enzymes.

The Angiotensin Converting Enzyme Insertion/Deletion Polymorphism Modifies Exercise-Induced Muscle Metabolism.

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David Vaughan

Full Text Available A silencer region (I-allele within intron 16 of the gene for the regulator of vascular perfusion, angiotensin-converting enzyme (ACE, is implicated in phenotypic variation of aerobic fitness and the development of type II diabetes. We hypothesised that the reportedly lower aerobic performance in non-carriers compared to carriers of the ACE I-allele, i.e. ACE-DD vs. ACE-ID/ACE-II genotype, is associated with alterations in activity-induced glucose metabolism and capillarisation in exercise muscle.Fifty-three, not-specifically trained Caucasian men carried out a one-legged bout of cycling exercise to exhaustion and/or participated in a marathon, the aim being to identify and validate genotype effects on exercise metabolism. Respiratory exchange ratio (RER, serum glucose and lipid concentration, glycogen, and metabolite content in vastus lateralis muscle based on ultra-performance lipid chromatography-mass spectrometry (UPLC-MS, were assessed before and after the cycling exercise in thirty-three participants. Serum metabolites were measured in forty subjects that completed the marathon. Genotype effects were assessed post-hoc.Cycling exercise reduced muscle glycogen concentration and this tended to be affected by the ACE I-allele (p = 0.09. The ACE-DD genotype showed a lower maximal RER and a selective increase in serum glucose concentration after exercise compared to ACE-ID and ACE-II genotypes (+24% vs. +2% and -3%, respectively. Major metabolites of mitochondrial metabolism (i.e. phosphoenol pyruvate, nicotinamide adenine dinucleotide phosphate, L-Aspartic acid, glutathione were selectively affected in vastus lateralis muscle by exercise in the ACE-DD genotype. Capillary-to-fibre ratio was 24%-lower in the ACE-DD genotype. Individuals with the ACE-DD genotype demonstrated an abnormal increase in serum glucose to 7.7 mM after the marathon.The observations imply a genetically modulated role for ACE in control of glucose import and oxidation in

Polymorphisms in heterocyclic aromatic amines metabolism-related genes are associated with colorectal adenoma risk.

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Eichholzer, Monika; Rohrmann, Sabine; Barbir, Aline; Hermann, Silke; Teucher, Birgit; Kaaks, Rudolf; Linseisen, Jakob

2012-01-01

Colorectal adenoma (CRA) and colorectal cancer (CRC) risks have been linked to the intake of red and processed meat. Heterocyclic aromatic amines (HCA) formed herein during high temperature cooking, are metabolized by a variety of enzymes, and allelic variation in the coding genes could influence individual CRA risk. Associations of polymorphisms in NAT1, NAT2, GSTA1, SULT1A1, CYP1A2, UGT1A7, UGT1A9, GSTP1 genes with colorectal adenoma risk were investigated in a nested case-control study of the EPIC-Heidelberg cohort including 428 cases matched by age, sex and year of recruitment with one or two controls (n=828) with negative colonoscopy per case. Genoyping was preformed with the Sequenom MassArray system and the LightCycler 480. Conditional logistic regression was used to compute odds ratios (OR) and corresponding 95% confidence intervals (CI). For rs15561 (NAT1) and rs1057126 (NAT1), the rarer allel was significantly inversely associated with adenoma risk OR=0.80 (95% CI 0.65-0.97) and (OR=0.81 (95% CI 0.65-0.99) and, respectively). For the combined NAT2 alleles encoding for enzymes with medium (versus slow) activity we also observed a significantly inverse association with adenoma risk (OR=0.75; 95% CI 0.85-0.97). In addition, homozygous carriers of the A allele of rs3957357 (GSTA1), i.e., those with a decreased enzyme activity, had a decreased risk of colorectal adenoma with an OR of 0.68 (95% CI 0.50-0.92; AA versus GG/GA). Polymorphisms in the other tested genes did not modify the risk of colorectal adenomas. In conclusion, polymorphisms in NAT1, NAT2, and GSTA1 are related to colorectal adenoma risk in this German cohort.

Effect of deletion polymorphism of angiotensin converting enzyme gene on progression of diabetic nephropathy during inhibition of angiotensin converting enzyme

DEFF Research Database (Denmark)

Parving, H H; Jacobsen, P; Tarnow, L

1996-01-01

OBJECTIVE: To evaluate the concept that an insertion/deletion polymorphism of the angiotensin converting enzyme gene predicts the therapeutic efficacy of inhibition of angiotensin converting enzyme on progression of diabetic nephropathy. DESIGN: Observational follow up study of patients with insu...

Enzyme clustering accelerates processing of intermediates through metabolic channeling

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Castellana, Michele; Wilson, Maxwell Z.; Xu, Yifan; Joshi, Preeti; Cristea, Ileana M.; Rabinowitz, Joshua D.; Gitai, Zemer; Wingreen, Ned S.

2015-01-01

We present a quantitative model to demonstrate that coclustering multiple enzymes into compact agglomerates accelerates the processing of intermediates, yielding the same efficiency benefits as direct channeling, a well-known mechanism in which enzymes are funneled between enzyme active sites through a physical tunnel. The model predicts the separation and size of coclusters that maximize metabolic efficiency, and this prediction is in agreement with previously reported spacings between coclusters in mammalian cells. For direct validation, we study a metabolic branch point in Escherichia coli and experimentally confirm the model prediction that enzyme agglomerates can accelerate the processing of a shared intermediate by one branch, and thus regulate steady-state flux division. Our studies establish a quantitative framework to understand coclustering-mediated metabolic channeling and its application to both efficiency improvement and metabolic regulation. PMID:25262299

From 20th century metabolic wall charts to 21st century systems biology: database of mammalian metabolic enzymes.

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Corcoran, Callan C; Grady, Cameron R; Pisitkun, Trairak; Parulekar, Jaya; Knepper, Mark A

2017-03-01

The organization of the mammalian genome into gene subsets corresponding to specific functional classes has provided key tools for systems biology research. Here, we have created a web-accessible resource called the Mammalian Metabolic Enzyme Database ( https://hpcwebapps.cit.nih.gov/ESBL/Database/MetabolicEnzymes/MetabolicEnzymeDatabase.html) keyed to the biochemical reactions represented on iconic metabolic pathway wall charts created in the previous century. Overall, we have mapped 1,647 genes to these pathways, representing ~7 percent of the protein-coding genome. To illustrate the use of the database, we apply it to the area of kidney physiology. In so doing, we have created an additional database ( Database of Metabolic Enzymes in Kidney Tubule Segments: https://hpcwebapps.cit.nih.gov/ESBL/Database/MetabolicEnzymes/), mapping mRNA abundance measurements (mined from RNA-Seq studies) for all metabolic enzymes to each of 14 renal tubule segments. We carry out bioinformatics analysis of the enzyme expression pattern among renal tubule segments and mine various data sources to identify vasopressin-regulated metabolic enzymes in the renal collecting duct. Copyright © 2017 the American Physiological Society.

Interactions between urinary 4-tert-octylphenol levels and metabolism enzyme gene variants on idiopathic male infertility.

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Yufeng Qin

Full Text Available Octylphenol (OP and Trichlorophenol (TCP act as endocrine disruptors and have effects on male reproductive function. We studied the interactions between 4-tert-Octylphenol (4-t-OP, 4-n- Octylphenol (4-n-OP, 2,3,4-Trichlorophenol (2,3,4-TCP, 2,4,5-Trichlorophenol (2,4,5-TCP urinary exposure levels and polymorphisms in selected xenobiotic metabolism enzyme genes among 589 idiopathic male infertile patients and 396 controls in a Han-Chinese population. Ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS was used to measure alkylphenols and chlorophenols in urine. Polymorphisms were genotyped using the SNPstream platform and the Taqman method. Among four phenols that were detected, we found that only exposure to 4-t-OP increased the risk of male infertility (P(trend = 1.70×10(-7. The strongest interaction was between 4-t-OP and rs4918758 in CYP2C9 (P(inter = 6.05×10(-7. It presented a significant monotonic increase in risk estimates for male infertility with increasing 4-t-OP exposure levels among men with TC/CC genotype (low level compared with non-exposed, odds ratio (OR = 2.26, 95% confidence intervals (CI = 1.06, 4.83; high level compared with non-exposed, OR = 9.22, 95% CI = 2.78, 30.59, but no associations observed among men with TT genotype. We also found interactions between 4-t-OP and rs4986894 in CYP2C19, and between rs1048943 in CYP1A1, on male infertile risk (P(inter = 8.09×10(-7, P(inter = 3.73×10(-4, respectively.We observed notable interactions between 4-t-OP exposure and metabolism enzyme gene polymorphisms on idiopathic infertility in Han-Chinese men.

Mediterranean dietary pattern and VEGF +405 G/C gene polymorphisms in patients with metabolic syndrome: An aspect of gene-nutrient interaction.

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Hajiluian, Ghazaleh; Abbasalizad Farhangi, Mahdieh; Jahangiry, Leila

2017-01-01

To evaluate the relationship between Mediterranean dietary pattern, anthropometric and metabolic biomarkers and vascular endothelial growth factor (VEGF) +405 G/C gene polymorphism in patient with metabolic syndrome (Mets). In this study 150 patients with Mets and 50 healthy subjects were enrolled. Dietary intakes were evaluated with a semi-quantitative food-frequency questionnaire (FFQ) and Mediterranean dietary quality index (Med-DQI) was assessed. Anthropometric assessments and blood pressure measurement were performed. Biochemical assays including fasting serum glucose (FSG), matrix metalloproteinase-3 (MMP-3), liver enzymes and lipid profiles were also assessed. Polymorphism of +405 G/C VEGF gene was determined utilizing polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) method. Serum high density lipoprotein-cholesterol (HDL-C) was significantly lower and low density lipoprotein cholesterol (LDL-C), triglyceride (TG), total cholesterol (TC) concentrations and FSG were significantly higher in metabolic syndrome patients compared with control group (P consumption of "cholesterol" had significantly upper serum TG; also high consumption of "fish" and "vegetables-fruits" was associated with a significantly lower serum LDL concentrations. In metabolic syndrome patients with CC genotype, mean score of "saturated fatty acid" subgroup was significantly higher compared with other genotypes; whereas, in healthy individuals, mean score of "fruit-vegetable" subgroup in individuals of CC and GG genotype was significantly higher (P<0.05). Our findings indicated a significant relationship between Mediterranean dietary quality index and both anthropometric and metabolic risk factors. We also indicated a higher "saturated fatty acid" intake in CC genotype among metabolic syndrome patients.

Role of Renin-Angiotensin-converting Enzyme Level and ACE Gene Polymorphism in Patients with Nonalcoholic Fatty Liver Disease.

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Tekatas, Demet D; Bahcecioglu, Ibrahim H; Ispiroglu, Murat; Sahin, Abdurrahman; Ilhan, Necip; Yalniz, Mehmet; Demirel, Ulvi

2016-01-01

In this study, we aimed to investigate the histological and clinical effect of angiotensin-converting enzyme (ACE) and ACE gene polymorphism in nonalcoholic fatty liver disease (NAFLD) and their roles in the progression of the disease. Liver function tests, body mass index, waist circumference, lipid parameters, fasting blood glucose (FBG), hemoglobin A1c (HbA1c), homeostasis model assessment-IR (HOMA-IR), ACE, and ACE gene polymorphism were evaluated in the NAFLD group and control group. The study group was evaluated by dividing the group into four subgroups by ACE gene polymorphism (D/D homozygous, I/I homozygous, D/I heterozygous, I/D heterozygous). Liver biopsies were evaluated according to Brunt Classification. A total of 31 patients who were diagnosed with NAFLD and 40 healthy individuals were included in the study. The ACE level was found to be 11.69 ± 1.99 in the NAFLD group and 11.52 ± 1.72 in the control group (p = 0.70). There was a negative correlation between ACE levels and HOMA-IR levels (p = 0.008, r= -0.512). Biochemical parameters were not different among ACE gene polimorphism subgroups, except FBG (between D/D, I/D and D/I, I/D; p = 0.02). When the ACE levels were compared in terms of grade and stage, no significant difference was found (for stage and grade p = 0.68). The ACE gene polymorphism subgroups did not differ by histopathologic findings; grade and stage (for grade p = 0.42, for stage p = 0.92). In this study, we could not find a correlation of ACE and ACE gene polymorphism with metabolic risk factors and the disease severity in NAFLD. Tekatas DD, Bahcecioglu IH, Ispiroglu M, Sahin A, Ilhan N, Yalniz M, Demirel U. Role of Renin-Angiotensin-converting Enzyme Level and ACE Gene Polymorphism in Patients with Nonalcoholic Fatty Liver Disease. Euroasian J Hepato-Gastroenterol 2016;6(2):137-142.

Individual Variations in Inorganic Arsenic Metabolism Associated with AS3MT Genetic Polymorphisms

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Haruo Takeshita

2011-04-01

Full Text Available Individual variations in inorganic arsenic metabolism may influence the toxic effects. Arsenic (+3 oxidation state methyltransferase (AS3MT that can catalyze the transfer of a methyl group from S-adenosyl-L-methionine (AdoMet to trivalent arsenical, may play a role in arsenic metabolism in humans. Since the genetic polymorphisms of AS3MT gene may be associated with the susceptibility to inorganic arsenic toxicity, relationships of several single nucleotide polymorphisms (SNPs in AS3MT with inorganic arsenic metabolism have been investigated. Here, we summarize our recent findings and other previous studies on the inorganic arsenic metabolism and AS3MT genetic polymorphisms in humans. Results of genotype dependent differences in arsenic metabolism for most of SNPs in AS3MT were Inconsistent throughout the studies. Nevertheless, two SNPs, AS3MT 12390 (rs3740393 and 14458 (rs11191439 were consistently related to arsenic methylation regardless of the populations examined for the analysis. Thus, these SNPs may be useful indicators to predict the arsenic metabolism via methylation pathways.

MTHFR polymorphisms and 5-FU-based adjuvant chemotherapy in colorectal cancer

DEFF Research Database (Denmark)

Afzal, Shoaib; Jensen, S; Vainer, B

2009-01-01

Methylenetetrahydrofolate reductase is a pivotal enzyme in folate metabolism and 5-fluorouracil (5-FU) cytotoxicity. Two common single-nucleotide polymorphisms (SNPs), MTHFR 677C>T (rs1801133) and 1298A>C (rs1801131), reduce enzyme activity. Initially, these SNPs were claimed to predict clinical...

Metabolic enzymes: key modulators of functionality in cancer stem-like cells.

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Dong, Bo-Wen; Qin, Guang-Ming; Luo, Yan; Mao, Jian-Shan

2017-02-21

Cancer Stem-like Cells (CSCs) are a subpopulation of cancer cells with self-renewal capacity and are important for the initiation, progression and recurrence of cancer diseases. The metabolic profile of CSCs is consistent with their stem-like properties. Studies have indicated that enzymes, the main regulators of cellular metabolism, dictate functionalities of CSCs in both catalysis-dependent and catalysis-independent manners. This paper reviews diverse studies of metabolic enzymes, and describes the effects of these enzymes on metabolic adaptation, gene transcription and signal transduction, in CSCs.

Tyrosine metabolic enzymes from insects and mammals: a comparative perspective.

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Vavricka, Christopher John; Han, Qian; Mehere, Prajwalini; Ding, Haizhen; Christensen, Bruce M; Li, Jianyong

2014-02-01

Differences in the metabolism of tyrosine between insects and mammals present an interesting example of molecular evolution. Both insects and mammals possess fine-tuned systems of enzymes to meet their specific demands for tyrosine metabolites; however, more homologous enzymes involved in tyrosine metabolism have emerged in many insect species. Without knowledge of modern genomics, one might suppose that mammals, which are generally more complex than insects and require tyrosine as a precursor for important catecholamine neurotransmitters and for melanin, should possess more enzymes to control tyrosine metabolism. Therefore, the question of why insects actually possess more tyrosine metabolic enzymes is quite interesting. It has long been known that insects rely heavily on tyrosine metabolism for cuticle hardening and for innate immune responses, and these evolutionary constraints are likely the key answers to this question. In terms of melanogenesis, mammals also possess a high level of regulation; yet mammalian systems possess more mechanisms for detoxification whereas insects accelerate pathways like melanogenesis and therefore must bear increased oxidative pressure. Our research group has had the opportunity to characterize the structure and function of many key proteins involved in tyrosine metabolism from both insects and mammals. In this mini review we will give a brief overview of our research on tyrosine metabolic enzymes in the scope of an evolutionary perspective of mammals in comparison to insects. © 2013 Institute of Zoology, Chinese Academy of Sciences.

ADIPOQ + 45T≥G Polymorphism, Food Ingestion, and Metabolic Syndrome in Elderly Persons.

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Retamoso, Vanessa R; Maurer, Patrícia; Feijóo, Lyana B; Tavares, Graziela M S; Manfredini, Vanusa; Piccoli, Jacqueline C E

2018-01-01

The current nutritional transition process contributes further to accelerate the onset of metabolic disorders, as do a number of environmental factors that lead to the diagnosis of chronic diseases, as a diet of low nutritional value, is possibly related to the incidence of metabolic syndrome. In addition to these factors, metabolic syndrome may also be related to genetic factors, the ADIPOQ + 45T> G polymorphism has been associated with serum adiponectin levels, insulin sensitivity, and obesity, which affects adiponectin levels act as protective factor for cardiovascular disease. In this way, the present study aimed to analyze the possible association between the ADIPOQ + 45T> G gene polymorphism, usual diet and metabolic syndrome in the elderly. We evaluated inflammatory and biochemical markers compared with older age groups (age 60 years) with and without metabolic syndrome. In addition to the anthropometric measurements of weight, height and waist circumference, the ADIPOQ + 45T> G gene polymorphism was determined by PCR- RFLP, and food consumption was investigated using a food frequency questionnaire. The study included 111 elderly individuals. Our main results show that there was a significant relationship between the habitual consumption of milk for the group that had metabolic syndrome (p metabolic syndrome. There was an association between habitual dietary intake of white meat with haplotypes TG and GG. We conclude that the relationship between the habitual consumption of certain food groups and ADIPOQ indicates the need for further studies to develop a better understanding of this relationship; however, there was no association between the ADIPOQ + 45T> G gene polymorphism and metabolic syndrome in the group of elderly studied.

Angiotensin Converting Enzyme Gene Insertion/Deletion Polymorphism in Migraine Patients

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Belgin Alaşehirli

2009-12-01

Full Text Available OBJECTIVE: The beneficial effects of angiotensin converting enzyme inhibitor drugs on migraine attack frequency have been shown. We aimed to study the relationship between the angiotensin converting enzyme gene and migraine pathophysiology. METHODS: In the present study, to assess whether the angiotensin converting enzyme insertion/deletion (I/D gene polymorphisms have an effect on migraine attacks, we studied the angiotensin converting enzyme genotypes of 102 migraine patients (35 cases of migraine with aura and 67 of migraine without aura and 75 age-and sex-matched normal volunteers. Frequency and age of onset of migraine attacks were also assessed according to angiotensin converting enzyme genotypes. RESULTS: Patients with migraine with and without aura were comparable with each other and the control group with respect to angiotensin converting enzyme genotypes (respectively; p= 0.88 and p= 0.76, p= 0.624. We could not determine a relationship between angiotensin converting enzyme genotypes and attack frequency (p= 0.125, but cases with angiotensin converting enzyme-II genotype showed a significantly younger age for onset of migraine attacks in comparison with the I/D genotype patients (p= 0.021. CONCLUSION: We believe that further angiotensin converting enzyme gene studies are warranted in younger age groups of patients with migraine and also in different populations

Drug Metabolizing Enzyme and Transporter Gene Variation, Nicotine Metabolism, Prospective Abstinence, and Cigarette Consumption.

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Andrew W Bergen

Full Text Available The Nicotine Metabolite Ratio (NMR, ratio of trans-3'-hydroxycotinine and cotinine, has previously been associated with CYP2A6 activity, response to smoking cessation treatments, and cigarette consumption. We searched for drug metabolizing enzyme and transporter (DMET gene variation associated with the NMR and prospective abstinence in 2,946 participants of laboratory studies of nicotine metabolism and of clinical trials of smoking cessation therapies. Stage I was a meta-analysis of the association of 507 common single nucleotide polymorphisms (SNPs at 173 DMET genes with the NMR in 449 participants of two laboratory studies. Nominally significant associations were identified in ten genes after adjustment for intragenic SNPs; CYP2A6 and two CYP2A6 SNPs attained experiment-wide significance adjusted for correlated SNPs (CYP2A6 PACT=4.1E-7, rs4803381 PACT=4.5E-5, rs1137115, PACT=1.2E-3. Stage II was mega-regression analyses of 10 DMET SNPs with pretreatment NMR and prospective abstinence in up to 2,497 participants from eight trials. rs4803381 and rs1137115 SNPs were associated with pretreatment NMR at genome-wide significance. In post-hoc analyses of CYP2A6 SNPs, we observed nominally significant association with: abstinence in one pharmacotherapy arm; cigarette consumption among all trial participants; and lung cancer in four case:control studies. CYP2A6 minor alleles were associated with reduced NMR, CPD, and lung cancer risk. We confirmed the major role that CYP2A6 plays in nicotine metabolism, and made novel findings with respect to genome-wide significance and associations with CPD, abstinence and lung cancer risk. Additional multivariate analyses with patient variables and genetic modeling will improve prediction of nicotine metabolism, disease risk and smoking cessation treatment prognosis.

Effect of AGTR1 and BDKRB2 gene polymorphisms on atorvastatin metabolism in a Mexican population

OpenAIRE

Herrera-González, Sarahí; Martínez-Treviño, Denisse Aideé; Aguirre-Garza, Marcelino; Gómez-Silva, Magdalena; Barrera-Saldaña, Hugo Alberto; León-Cachón, Rafael Baltazar Reyes

2017-01-01

Discrepancies in the response to drugs are partially due to polymorphisms in genes involved in drug metabolism and transport. The frequency, pattern and impact of these polymorphisms vary among populations. In the present study, the pharmacokinetics and pharmacogenetics of atorvastatin (ATV) in a Mexican population were investigated. The study cohort exhibited differing ATV metabolizing phenotypes, and in subsequent allelic discrimination assays, single nucleotide polymorphisms in the angiote...

Action of ionizing radiation on the carbohydrate metabolism enzymes

International Nuclear Information System (INIS)

Cherkasova, L.S.; Mironova, T.M.

1976-01-01

It follows from data reported in literature and those obtained in our laboratory that ionizing radiation does not drastically change the activity of enzymes of the carbohydrate metabolism in tissues of an animal organism. The data are reported on the effect of a whole-body single, fractionated or continuous irradiation of the enzymes of carbohydrate metabolism and the accompanying interrelated co-operative redistributions within the processes of aerobic and anaerobic glycolysis, and the pentose route of their conversion. The dependence of the postirradiation changes in the activity of enzymes on the neuroendocrine system response to irradiation has been demonstrated

Relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women.

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Mehanna, Eman T; Saleh, Samy M; Ghattas, Maivel H; Mesbah, Noha M; Abo-Elmatty, Dina M

2015-02-01

Myeloperoxidase is a heme protein secreted by activated macrophages and generates intermediates that oxidize lipoproteins. Myeloperoxidase-463G/A is a functional polymorphism involved in regulation of myeloperoxidase expression. The aim of this study is to assess the relation of myeloperoxidase-463G/A polymorphism with metabolic syndrome and its component traits in Egyptian women from the Suez Canal area. The study includes 100 healthy female subjects and 100 metabolic syndrome patients. The component traits of metabolic syndrome are determined and the genotypes of the polymorphisms assessed using the PCR-RFLP technique. There was no significant difference in the allele frequencies between the metabolic syndrome and control groups. However, the GA and AA genotypes were associated with lower total cholesterol, LDL-C, systolic and diastolic blood pressure in the patients. Myeloperoxidase-463G/A polymorphism is not associated with the incidence of metabolic syndrome.

The association between angiotensin-converting enzyme gene polymorphism and coronary calcification - The Rotterdam Coronary Calcification Study

NARCIS (Netherlands)

Oei, HHS; Sayed-Tabatabaei, FA; Hofman, A; Oudkerk, M; van Duijn, CM; Witteman, JCM

Background: An insertion/deletion (I/D) polymorphism in the gene encoding angiotensin-converting enzyme (ACE) has been associated with serum ACE levels. The association between the ACE I/D polymorphism and coronary heart disease is unclear. Electron-beam-computed tomography (EBT) is a technique to

A High-Throughput (HTS) Assay for Enzyme Reaction Phenotyping in Human Recombinant P450 Enzymes Using LC-MS/MS.

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Li, Xiaofeng; Suhar, Tom; Glass, Lateca; Rajaraman, Ganesh

2014-03-03

Enzyme reaction phenotyping is employed extensively during the early stages of drug discovery to identify the enzymes responsible for the metabolism of new chemical entities (NCEs). Early identification of metabolic pathways facilitates prediction of potential drug-drug interactions associated with enzyme polymorphism, induction, or inhibition, and aids in the design of clinical trials. Incubation of NCEs with human recombinant enzymes is a popular method for such work because of the specificity, simplicity, and high-throughput nature of this approach for phenotyping studies. The availability of a relative abundance factor and calculated intersystem extrapolation factor for the expressed recombinant enzymes facilitates easy scaling of in vitro data, enabling in vitro-in vivo extrapolation. Described in this unit is a high-throughput screen for identifying enzymes involved in the metabolism of NCEs. Emphasis is placed on the analysis of the human recombinant enzymes CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2B6, and CYP3A4, including the calculation of the intrinsic clearance for each. Copyright © 2014 John Wiley & Sons, Inc. All rights reserved.

The polymorphism of estrogen receptor α is important for metabolic consequences associated with menopause.

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Pinkas, Jarosław; Gujski, Mariusz; Wierzbińska-Stępniak, Anna; Owoc, Alfred; Bojar, Iwona

2016-01-01

Menopause is associated with multiple health and metabolic consequences resulting from the decrease in estrogens level. Women at postmenopausal age are burdened with a higher risk of cardiovascular diseases, and the main cause of mortality in this group is ischemic heart disease. Estrogen deficiency is related, among other things, with frequent occurrence of dislipidemia, cessation of the beneficial effect of estrogens on the vascular wall, increase in body weight characterized by unfavourable redistribution of fatty tissue, with an increased amount of visceral fat and reduction of so-called non-fatty body mass. Estrogens exert an effect on metabolism, mainly through the genomic mechanism. The presence of α and β estrogen receptors was found in many tissues and organs. Recently, attention was paid to the fact that the effect of estrogens action on tissues and organs may depend not only on distribution, but also on their polymorphic types. The article presents the latest approach to the problem of metabolic consequences resulting from menopause, according to the possessed α estrogen receptor polymorphism (ERα).Genes encoding for ERα have many polymorphic variants, the most important of which from the clinical aspect are two single nucleotide polymorphisms (SNPs) - Xba1 and PvuII. The review of literature indicates that ERα polymorphisms are of great importance with respect to the effect of estrogens on the functioning of the body of a woman after menopause, and may imply the development of many pathological states, including the prevention or development of metabolic disorders. Identifying ERα polymorphisms may be useful in case of estrogen therapy for menopausal women who may benefit from it.

Comparative gene expression of intestinal metabolizing enzymes.

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Shin, Ho-Chul; Kim, Hye-Ryoung; Cho, Hee-Jung; Yi, Hee; Cho, Soo-Min; Lee, Dong-Goo; Abd El-Aty, A M; Kim, Jin-Suk; Sun, Duxin; Amidon, Gordon L

2009-11-01

The purpose of this study was to compare the expression profiles of drug-metabolizing enzymes in the intestine of mouse, rat and human. Total RNA was isolated from the duodenum and the mRNA expression was measured using Affymetrix GeneChip oligonucleotide arrays. Detected genes from the intestine of mouse, rat and human were ca. 60% of 22690 sequences, 40% of 8739 and 47% of 12559, respectively. Total genes of metabolizing enzymes subjected in this study were 95, 33 and 68 genes in mouse, rat and human, respectively. Of phase I enzymes, the mouse exhibited abundant gene expressions for Cyp3a25, Cyp4v3, Cyp2d26, followed by Cyp2b20, Cyp2c65 and Cyp4f14, whereas, the rat showed higher expression profiles of Cyp3a9, Cyp2b19, Cyp4f1, Cyp17a1, Cyp2d18, Cyp27a1 and Cyp4f6. However, the highly expressed P450 enzymes were CYP3A4, CYP3A5, CYP4F3, CYP2C18, CYP2C9, CYP2D6, CYP3A7, CYP11B1 and CYP2B6 in the human. For phase II enzymes, glucuronosyltransferase Ugt1a6, glutathione S-transferases Gstp1, Gstm3 and Gsta2, sulfotransferase Sult1b1 and acyltransferase Dgat1 were highly expressed in the mouse. The rat revealed predominant expression of glucuronosyltransferases Ugt1a1 and Ugt1a7, sulfotransferase Sult1b1, acetyltransferase Dlat and acyltransferase Dgat1. On the other hand, in human, glucuronosyltransferases UGT2B15 and UGT2B17, glutathione S-transferases MGST3, GSTP1, GSTA2 and GSTM4, sulfotransferases ST1A3 and SULT1A2, acetyltransferases SAT1 and CRAT, and acyltransferase AGPAT2 were dominantly detected. Therefore, current data indicated substantial interspecies differences in the pattern of intestinal gene expression both for P450 enzymes and phase II drug-metabolizing enzymes. This genomic database is expected to improve our understanding of interspecies variations in estimating intestinal prehepatic clearance of oral drugs.

Integration of Genome Scale Metabolic Networks and Gene Regulation of Metabolic Enzymes With Physiologically Based Pharmacokinetics.

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Maldonado, Elaina M; Leoncikas, Vytautas; Fisher, Ciarán P; Moore, J Bernadette; Plant, Nick J; Kierzek, Andrzej M

2017-11-01

The scope of physiologically based pharmacokinetic (PBPK) modeling can be expanded by assimilation of the mechanistic models of intracellular processes from systems biology field. The genome scale metabolic networks (GSMNs) represent a whole set of metabolic enzymes expressed in human tissues. Dynamic models of the gene regulation of key drug metabolism enzymes are available. Here, we introduce GSMNs and review ongoing work on integration of PBPK, GSMNs, and metabolic gene regulation. We demonstrate example models. © 2017 The Authors CPT: Pharmacometrics & Systems Pharmacology published by Wiley Periodicals, Inc. on behalf of American Society for Clinical Pharmacology and Therapeutics.

Levels of Key Enzymes of Methionine-Homocysteine Metabolism in Preeclampsia

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Alejandra Pérez-Sepúlveda

2013-01-01

Full Text Available Objective. To evaluate the role of key enzymes in the methionine-homocysteine metabolism (MHM in the physiopathology of preeclampsia (PE. Methods. Plasma and placenta from pregnant women (32 controls and 16 PE patients were analyzed after informed consent. Protein was quantified by western blot. RNA was obtained with RNA purification kit and was quantified by reverse transcritase followed by real-time PCR (RT-qPCR. Identification of the C677T and A1298C methylenetetrahydrofolate reductase (MTHFR single-nucleotide polymorphisms (SNPs and A2756G methionine synthase (MTR SNP was performed using PCR followed by a high-resolution melting (HRM analysis. S-adenosyl methionine (SAM and S-adenosyl homocysteine (SAH were measured in plasma using high-performance liquid chromatography-tandem mass spectrometry (HPLC/MS/MS. The SNP association analysis was carried out using Fisher’s exact test. Statistical analysis was performed using a Mann-Whitney test. Results. RNA expression of MTHFR and MTR was significantly higher in patients with PE as compared with controls. Protein, SAM, and SAH levels showed no significant difference between preeclamptic patients and controls. No statistical differences between controls and PE patients were observed with the different SNPs studied. Conclusion. The RNA expression of MTHFR and MTR is elevated in placentas of PE patients, highlighting a potential compensation mechanism of the methionine-homocysteine metabolism in the physiopathology of this disease.

Null association of maternal MTHFR A1298C polymorphism with ...

African Journals Online (AJOL)

Background: Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme of folate/homocysteine pathway and is essential for DNA synthesis and methylation. MTHFR gene polymorphisms have been reported as risk factors for congenital defects and several metabolic and neurological disorders. Several studies ...

Engineering of metabolic pathways by artificial enzyme channels

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Marlene ePröschel

2015-10-01

Full Text Available Application of industrial enzymes for production of valuable chemical compounds has greatly benefited from recent developments in Systems and Synthetic Biology. Both, in vivo and in vitro systems have been established, allowing conversion of simple into complex compounds. Metabolic engineering in living cells needs to be balanced which is achieved by controlling gene expression levels, translation, scaffolding, compartmentation and flux control. In vitro applications are often hampered by limited protein stability/half-life and insufficient rates of substrate conversion. To improve stability and catalytic activity, proteins are post-translationally modified and arranged in artificial metabolic channels. Within the review article we will first discuss the supramolecular organization of enzymes in living systems and secondly summarize current and future approaches to design artificial metabolic channels by additive manufacturing for the efficient production of desired products.

Angiotensin-converting enzyme activity in Cavalier King Charles Spaniels with an ACE gene polymorphism and myxomatous mitral valve disease

DEFF Research Database (Denmark)

Meurs, Kathryn M.; Olsen, Lisbeth H.; Reimann, Maria J.

2018-01-01

a canine ACE gene polymorphism associated with a decrease in angiotensin-converting enzyme (ACE) activity. The aim of this study was to evaluate for the prevalence of the ACE polymorphism in CKCS with mitral valve disease and to determine whether the presence of the polymorphism is associated......Objectives Myxomatous mitral valve disease (MMVD) is the most common heart disease in the dog. It is particularly common in the Cavalier King Charles Spaniel (CKCS) breed and affected dogs are frequently managed with angiotensin-converting enzyme inhibitors (ACE-I). We have previously identified...... with alterations in ACE activity at different stages of cardiac disease. Methods Seventy-three dogs with a diagnosis of mitral valve disease were evaluated and a blood sample was drawn for ACE polymorphism genotyping and ACE activity measurement. Results Forty-three dogs were homozygous for the ACE polymorphism...

Major Components of Metabolic Parameters and Nutritional Intakes in Different Genotypes of Adiponectin +276 G>T Gene Polymorphism in Non-Diabetes and Non-Alcoholic Iranian Fatty Liver Patients.

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Mohseni, Fatemeh; Moghbelinejad, Sahar; Najafipour, Reza

2017-01-01

Genetic and environmental factors are both involved in the etiology of Non-Alcoholic Fatty Liver Disease (NAFLD). Among the genetic factors, certain polymorphisms of adiponectin gene are associated with NAFLD. In the current study, we investigated the association between metabolic parameters with different genotypes of adiponectin +276 G>T polymorphism among the Iranian NAFLD patients, and the effect of nutritional intake with development of NAFLD. In this study, 75 patients with NAFLD and 76 healthy individuals were enrolled. Dietary intakes were assessed using a semi-quantitative Food-Frequency Questionnaire (FFQ). Body Mass Index (BMI) and Waist to Hip Ratio (WHR) were calculated. Biochemical assays including FSG (Fasting Serum Glucose), liver enzymes, lipid profiles, Malondialdehyde, insulin resistance and Total Antioxidant Capacity (TAC) were measured after 12 hr fasting. Gene polymorphism study was done by using of sequencing method. Although, T allele frequency was more prevalent in patients with NAFLD than control, adiponectin +276 G>T polymorphism was not associated with risk of NAFLD. Among the metabolic parameters, TAC in TT genotype was significantly lower 1.44(0.69 to 2.81) p>0.05, AST in GT, GG genotypes, and ALT in all three genotypes were higher in NAFLD patients in compared to healthy subjects (pconsumption and vitamin E intake as compared to control group with the same genotype (pstudy, we showed the association of different genotypes of +276 G>T polymorphism in adiponectin gene with some metabolic parameters.

Expression of Enzymes that Metabolize Medications

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Wotring, Virginia E.; Peters, C. P.

2012-01-01

Most pharmaceuticals are metabolized by the liver. Clinically-used medication doses are given with normal liver function in mind. A drug overdose can result if the liver is damaged and removing pharmaceuticals from the circulation at a rate slower than normal. Alternatively, if liver function is elevated and removing drugs from the system more quickly than usual, it would be as if too little drug had been given for effective treatment. Because of the importance of the liver in drug metabolism we want to understand the effects of spaceflight on the enzymes of the liver.

Metabolism and gene polymorphisms of the folate pathway in Brazilian women with history of recurrent abortion.

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Boas, Wendell Vilas; Gonçalves, Rozana Oliveira; Costa, Olívia Lúcia Nunes; Goncalves, Marilda Souza

2015-02-01

To investigate the association between polymorphisms in genes that encode enzymes involved in folate- and vitamin B12-dependent homocysteine metabolism and recurrent spontaneous abortion (RSA). We investigated the C677T and A1298C polymorphisms of the methylenetetrahydrofalate reductase gene (MTHFR), the A2756G polymorphism of the methionine synthase gene (MS) and the 844ins68 insertion of the cystathionine beta synthetase gene (CBS). The PCR technique followed by RFLP was used to assess the polymorphisms; the serum levels of homocysteine, vitamin B12 and folate were investigated by chemiluminescence. The EPI Info Software version 6.04 was used for statistical analysis. Parametric variables were compared by Student's t-test and nonparametric variables by the Wilcoxon rank sum test. The frequencies of gene polymorphisms in 89 women with a history of idiopathic recurrent miscarriage and 150 controls were 19.1 and 19.6% for the C677T, insertion, 20.8 and 26% for the A1298C insertion, 14.2 and 21.9% for the A2756G insertion, and 16.4 and 18% for the 844ins68 insertion, respectively. There were no significant differences between case and control groups in any of the gene polymorphisms investigated. However, the frequency of the 844ins68 insertion in the CBS gene was higher among women with a history of loss during the third trimester of pregnancy (p=0.003). Serum homocysteine, vitamin B12 and folate levels id not differ between the polymorphisms studied in the case and control groups. However, linear regression analysis showed a dependence of serum folate levels on the maintenance of tHcy levels. The investigated gene polymorphisms and serum homocysteine, vitamin B12 and folate levels were not associated with idiopathic recurrent miscarriage in the present study. Further investigations are needed in order to confirm the role of the CBS 844ins68 insertion in recurrent miscarriage.

[POLYMORPHISM OF ALFA-AMYLASE AND CONJUGATION IN COMMON WHEAT ENZYME TYPES WITH QUANTITATIVE TRAITS OF PLANTS].

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Netsvetaev, V P; Bondarenko, L S; Motorina, I P

2015-01-01

Using polymorphism of alpha-amylase in the winter common wheat studied inheritance isoenzymes and its conjugation enzyme types with germinating grain on the "vine", grain productivity, plant height and time of ear formation. It is shown that the polymorphism isoenzyme of alpha-amylase wheat is limited by the presence of different loci whose products are similar in electrophoretic parameters. In this regard, one component of the enzyme can be controlling at one or two or three genes. Identification of a locus controlling alpha-amylase isoenzyme in the fast moving part of the electrophoretogram, designated as α-Amy-B7. Determine the distance of the locus to factor α-Amy-B6.

Identification of parallel and divergent optimization solutions for homologous metabolic enzymes

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Robert F. Standaert

2018-06-01

Full Text Available Metabolic pathway assembly typically involves the expression of enzymes from multiple organisms in a single heterologous host. Ensuring that each enzyme functions effectively can be challenging, since many potential factors can disrupt proper pathway flux. Here, we compared the performance of two enzyme homologs in a pathway engineered to allow Escherichia coli to grow on 4-hydroxybenzoate (4-HB, a byproduct of lignocellulosic biomass deconstruction. Single chromosomal copies of the 4-HB 3-monooxygenase genes pobA and praI, from Pseudomonas putida KT2440 and Paenibacillus sp. JJ-1B, respectively, were introduced into a strain able to metabolize protocatechuate (PCA, the oxidation product of 4-HB. Neither enzyme initially supported consistent growth on 4-HB. Experimental evolution was used to identify mutations that improved pathway activity. For both enzymes, silent mRNA mutations were identified that increased enzyme expression. With pobA, duplication of the genes for PCA metabolism allowed growth on 4-HB. However, with praI, growth required a mutation in the 4-HB/PCA transporter pcaK that increased intracellular concentrations of 4-HB, suggesting that flux through PraI was limiting. These findings demonstrate the value of directed evolution strategies to rapidly identify and overcome diverse factors limiting enzyme activity. Keywords: Lignin, Protocatechuate, Experimental evolution

Identification of parallel and divergent optimization solutions for homologous metabolic enzymes.

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Standaert, Robert F; Giannone, Richard J; Michener, Joshua K

2018-06-01

Metabolic pathway assembly typically involves the expression of enzymes from multiple organisms in a single heterologous host. Ensuring that each enzyme functions effectively can be challenging, since many potential factors can disrupt proper pathway flux. Here, we compared the performance of two enzyme homologs in a pathway engineered to allow Escherichia coli to grow on 4-hydroxybenzoate (4-HB), a byproduct of lignocellulosic biomass deconstruction. Single chromosomal copies of the 4-HB 3-monooxygenase genes pobA and praI , from Pseudomonas putida KT2440 and Paenibacillus sp. JJ-1B, respectively, were introduced into a strain able to metabolize protocatechuate (PCA), the oxidation product of 4-HB. Neither enzyme initially supported consistent growth on 4-HB. Experimental evolution was used to identify mutations that improved pathway activity. For both enzymes, silent mRNA mutations were identified that increased enzyme expression. With pobA , duplication of the genes for PCA metabolism allowed growth on 4-HB. However, with praI , growth required a mutation in the 4-HB/PCA transporter pcaK that increased intracellular concentrations of 4-HB, suggesting that flux through PraI was limiting. These findings demonstrate the value of directed evolution strategies to rapidly identify and overcome diverse factors limiting enzyme activity.

Molecular Identification, Enzyme Assay, and Metabolic Profiling of Trichoderma spp.

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Bae, Soo-Jung; Park, Young-Hwan; Bae, Hyeun-Jong; Jeon, Junhyun; Bae, Hanhong

2017-06-28

The goal of this study was to identify and characterize selected Trichoderma isolates by metabolic profiling and enzyme assay for evaluation of their potential as biocontrol agents against plant pathogens. Trichoderma isolates were obtained from the Rural Development Administration Genebank Information Center (Wanju, Republic of Korea). Eleven Trichoderma isolates were re-identified using ribosomal DNA internal transcribed spacer (ITS) regions. ITS sequence results showed new identification of Trichoderma isolates. In addition, metabolic profiling of the ethyl acetate extracts of the liquid cultures of five Trichoderma isolates that showed the best anti- Phytophthora activities was conducted using gas chromatography-mass spectrometry. Metabolic profiling revealed that Trichoderma isolates shared common metabolites with well-known antifungal activities. Enzyme assays indicated strong cell walldegrading enzyme activities of Trichoderma isolates. Overall, our results indicated that the selected Trichoderma isolates have great potential for use as biocontrol agents against plant pathogens.

Monoamine oxidase A gene polymorphisms and enzyme activity associated with risk of gout in Taiwan aborigines.

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Tu, Hung-Pin; Ko, Albert Min-Shan; Wang, Shu-Jung; Lee, Chien-Hung; Lea, Rod A; Chiang, Shang-Lun; Chiang, Hung-Che; Wang, Tsu-Nai; Huang, Meng-Chuan; Ou, Tsan-Teng; Lin, Gau-Tyan; Ko, Ying-Chin

2010-02-01

Taiwanese aborigines have a high prevalence of hyperuricemia and gout. Uric acid levels and urate excretion have correlated with dopamine-induced glomerular filtration response. MAOs represent one of the major renal dopamine metabolic pathways. We aimed to identify the monoamine oxidase A (MAOA, Xp11.3) gene variants and MAO-A enzyme activity associated with gout risk. This study was to investigate the association between gout and the MAOA single-nucleotide polymorphisms (SNPs) rs5953210, rs2283725, and rs1137070 as well as between gout and the COMT SNPs rs4680 Val158Met for 374 gout cases and 604 controls. MAO-A activity was also measured. All three MAOA SNPs were significantly associated with gout. A synonymous MAOA SNP, rs1137070 Asp470Asp, located in exon 14, was associated with the risk of having gout (P = 4.0 x 10(-5), adjusted odds ratio 1.46, 95% confidence intervals [CI]: 1.11-1.91). We also showed that, when compared to individuals with the MAOA GAT haplotype, carriers of the AGC haplotype had a 1.67-fold (95% CI: 1.28-2.17) higher risk of gout. Moreover, we found that MAOA enzyme activity correlated positively with hyperuricemia and gout (P for trend = 2.00 x 10(-3) vs. normal control). We also found that MAOA enzyme activity by rs1137070 allele was associated with hyperuricemia and gout (P for trend = 1.53 x 10(-6) vs. wild-type allele). Thus, our results show that some MAOA alleles, which have a higher enzyme activity, predispose to the development of gout.

Angiotensin-converting enzyme gene 2350 G/A polymorphism and susceptibility to atrial fibrillation in Han Chinese patients with essential hypertension

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Min-Hui Jiang

2013-11-01

Full Text Available OBJECTIVE: The angiotensin-converting enzyme gene is one of the most studied candidate genes related to atrial fibrillation. Among the polymorphisms of the angiotensin-converting enzyme gene, the 2350 G/A polymorphism (rs4343 is known to have the most significant effects on the plasma angiotensin-converting enzyme concentration. The aim of the present study was to investigate the association of the angiotensin-converting enzyme 2350 G/A polymorphism with atrial fibrillation in Han Chinese patients with essential hypertension. METHODS: A total of 169 hypertensive patients were eligible for this study. Patients with atrial fibrillation (n = 75 were allocated to the atrial fibrillation group, and 94 subjects without atrial fibrillation were allocated to the control group. The PCR-based restriction fragment length polymorphism technique was used to assess the genotype frequencies. RESULTS: The distributions of the angiotensin-converting enzyme 2350 G/A genotypes (GG, GA, and AA, respectively were 40.43%, 41.49%, and 18.08% in the controls and 18.67%, 46.67%, and 34.66% in the atrial fibrillation subjects (p = 0.037. The frequency of the A allele in the atrial fibrillation group was significantly greater than in the control group (58.00% vs. 38.83%, p = 0.0007. Compared with the wild-type GG genotype, the GA and AA genotypes had an increased risk for atrial fibrillation. Additionally, atrial fibrillation patients with the AA genotype had greater left atrial dimensions than the patients with the GG or GA genotypes (p<0.01 and p<0.05, respectively. CONCLUSIONS: The results obtained in this study indicate that the angiotensin-converting enzyme 2350 G/A polymorphism is associated with atrial fibrillation and that the A allele shows an increased risk for atrial fibrillation in Han Chinese patients with essential hypertension.

A Kinetic Modelling of Enzyme Inhibitions in the Central Metabolism of Yeast Cells

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Kasbawati; Kalondeng, A.; Aris, N.; Erawaty, N.; Azis, M. I.

2018-03-01

Metabolic regulation plays an important role in the metabolic engineering of a cellular process. It is conducted to improve the productivity of a microbial process by identifying the important regulatory nodes of a metabolic pathway such as fermentation pathway. Regulation of enzymes involved in a particular pathway can be held to improve the productivity of the system. In the central metabolism of yeast cell, some enzymes are known as regulating enzymes that can be inhibited to increase the production of ethanol. In this research we study the kinetic modelling of the enzymes in the central pathway of yeast metabolism by taking into consideration the enzyme inhibition effects to the ethanol production. The existence of positive steady state solution and the stability of the system are also analysed to study the property and dynamical behaviour of the system. One stable steady state of the system is produced if some conditions are fulfilled. The conditions concern to the restriction of the maximum reactions of the enzymes in the pyruvate and acetaldehyde branch points. There exists a certain time of fermentation reaction at which a maximum and a minimum ethanol productions are attained after regulating the system. Optimal ethanol concentration is also produced for a certain initial concentration of inhibitor.

Relationship between angiotensin-converting enzyme gene polymorphism and cardio-brain complications in patients with NIDDM (type 2 diabetes mellitus)

International Nuclear Information System (INIS)

Xu Qinfang; Zhu Yan; Ding Mingwei

2002-01-01

Objective: To investigate the relationship between angiotensin-converting enzyme gene polymorphism and cardio-brain complications in patients with NIDDM. Methods: The angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism in 174 patients with NIDDM and 62 controls were examined with PCR. Results: ACE gene I/D polymorphism was closely related to coronary heart disease (angina, cardiac infarction) and cerebral infarction in diabetic patients but not with hypertension. Plasma renin activity and plasma angiotensin II levels in complicated diabetic patients with ACE D/D gene were significantly higher than those in the controls (p < 0.01). Their aldosterone and endothelin contents were not significantly different. Conclusion: Examination of ACE gene I/D polymorphism was useful for the primary prevention of cardio-brain complications in diabetic patients and helpful in the early diagnosis and therapy of coronary heart disease and cerebral infarction

Flavonoids as modulators of metabolic enzymes and drug transporters.

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Miron, Anca; Aprotosoaie, Ana Clara; Trifan, Adriana; Xiao, Jianbo

2017-06-01

Flavonoids, natural compounds found in plants and in plant-derived foods and beverages, have been extensively studied with regard to their capacity to modulate metabolic enzymes and drug transporters. In vitro, flavonoids predominantly inhibit the major phase I drug-metabolizing enzyme CYP450 3A4 and the enzymes responsible for the bioactivation of procarcinogens (CYP1 enzymes) and upregulate the enzymes involved in carcinogen detoxification (UDP-glucuronosyltransferases, glutathione S-transferases (GSTs)). Flavonoids have been reported to inhibit ATP-binding cassette (ABC) transporters (multidrug resistance (MDR)-associated proteins, breast cancer-resistance protein) that contribute to the development of MDR. P-glycoprotein, an ABC transporter that limits drug bioavailability and also induces MDR, was differently modulated by flavonoids. Flavonoids and their phase II metabolites (sulfates, glucuronides) inhibit organic anion transporters involved in the tubular uptake of nephrotoxic compounds. In vivo studies have partially confirmed in vitro findings, suggesting that the mechanisms underlying the modulatory effects of flavonoids are complex and difficult to predict in vivo. Data summarized in this review strongly support the view that flavonoids are promising candidates for the enhancement of oral drug bioavailability, chemoprevention, and reversal of MDR. © 2017 New York Academy of Sciences.

Modeling metabolic response to changes of enzyme amount in ...

African Journals Online (AJOL)

Based on the work of Hynne et al. (2001), in an in silico model of glycolysis, Saccharomyces cerevisiae is established by introducing an enzyme amount multiple factor (.) into the kinetic equations. The model is aimed to predict the metabolic response to the change of enzyme amount. With the help of .α, the amounts of ...

Proteolytic regulation of metabolic enzymes by E3 ubiquitin ligase complexes: lessons from yeast.

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Nakatsukasa, Kunio; Okumura, Fumihiko; Kamura, Takumi

2015-01-01

Eukaryotic organisms use diverse mechanisms to control metabolic rates in response to changes in the internal and/or external environment. Fine metabolic control is a highly responsive, energy-saving process that is mediated by allosteric inhibition/activation and/or reversible modification of preexisting metabolic enzymes. In contrast, coarse metabolic control is a relatively long-term and expensive process that involves modulating the level of metabolic enzymes. Coarse metabolic control can be achieved through the degradation of metabolic enzymes by the ubiquitin-proteasome system (UPS), in which substrates are specifically ubiquitinated by an E3 ubiquitin ligase and targeted for proteasomal degradation. Here, we review select multi-protein E3 ligase complexes that directly regulate metabolic enzymes in Saccharomyces cerevisiae. The first part of the review focuses on the endoplasmic reticulum (ER) membrane-associated Hrd1 and Doa10 E3 ligase complexes. In addition to their primary roles in the ER-associated degradation pathway that eliminates misfolded proteins, recent quantitative proteomic analyses identified native substrates of Hrd1 and Doa10 in the sterol synthesis pathway. The second part focuses on the SCF (Skp1-Cul1-F-box protein) complex, an abundant prototypical multi-protein E3 ligase complex. While the best-known roles of the SCF complex are in the regulation of the cell cycle and transcription, accumulating evidence indicates that the SCF complex also modulates carbon metabolism pathways. The increasing number of metabolic enzymes whose stability is directly regulated by the UPS underscores the importance of the proteolytic regulation of metabolic processes for the acclimation of cells to environmental changes.

Something Old, Something New: Conserved Enzymes and the Evolution of Novelty in Plant Specialized Metabolism1

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Moghe, Gaurav D.; Last, Robert L.

2015-01-01

Plants produce hundreds of thousands of small molecules known as specialized metabolites, many of which are of economic and ecological importance. This remarkable variety is a consequence of the diversity and rapid evolution of specialized metabolic pathways. These novel biosynthetic pathways originate via gene duplication or by functional divergence of existing genes, and they subsequently evolve through selection and/or drift. Studies over the past two decades revealed that diverse specialized metabolic pathways have resulted from the incorporation of primary metabolic enzymes. We discuss examples of enzyme recruitment from primary metabolism and the variety of paths taken by duplicated primary metabolic enzymes toward integration into specialized metabolism. These examples provide insight into processes by which plant specialized metabolic pathways evolve and suggest approaches to discover enzymes of previously uncharacterized metabolic networks. PMID:26276843

Experiment K-6-21. Effect of microgravity on 1) metabolic enzymes of type 1 and type 2 muscle fibers and on 2) metabolic enzymes, neutransmitter amino acids, and neurotransmitter associated enzymes in motor and somatosensory cerebral cortex. Part 1: Metabolic enzymes of individual muscle fibers; part 2: metabolic enzymes of hippocampus and spinal cord

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Lowry, O.; Mcdougal, D., Jr.; Nemeth, Patti M.; Maggie, M.-Y. Chi; Pusateri, M.; Carter, J.; Manchester, J.; Norris, Beverly; Krasnov, I.

1990-01-01

The individual fibers of any individual muscle vary greatly in enzyme composition, a fact which is obscured when enzyme levels of a whole muscle are measured. The purpose of this study was therefore to assess the changes due to weightless on the enzyme patterns composed by the individual fibers within the flight muscles. In spite of the limitation in numbers of muscles examined, it is apparent that: (1) that the size of individual fibers (i.e., their dry weight) was reduced about a third, (2) that this loss in dry mass was accompanied by changes in the eight enzymes studied, and (3) that these changes were different for the two muscles, and different for the two enzyme groups. In the soleus muscle the absolute amounts of the three enzymes of oxidative metabolism decreased about in proportion to the dry weight loss, so that their concentration in the atrophic fibers was almost unchanged. In contrast, there was little loss among the four enzymes of glycogenolysis - glycolysis so that their concentrations were substantially increased in the atrophic fibers. In the TA muscle, these seven enzymes were affected in just the opposite direction. There appeared to be no absolute loss among the oxidative enzymes, whereas the glycogenolytic enzymes were reduced by nearly half, so that the concentrations of the first metabolic group were increased within the atrophic fibers and the concentrations of the second group were only marginally decreased. The behavior of hexokinase was exceptional in that it did not decrease in absolute terms in either type of muscle and probably increased as much as 50 percent in soleus. Thus, their was a large increase in concentration of this enzyme in the atrophied fibers of both muscles. Another clear-cut finding was the large increase in the range of activities of the glycolytic enzymes among individual fibers of TA muscles. This was due to the emergence of TA fibers with activities for enzymes of this group extending down to levels as low as

Association of Angiotensin-Converting Enzyme Genotype, Insertion/Deletion Polymorphism and Saphenous Vein Graft Atherosclerosis in Iranian Patients

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Neda Zeinali

2015-10-01

Full Text Available ABSTRACT OBJECTIVE: The aim of this study was to evaluate possible interactions among Angiotensin-I converting enzyme genotype, insertion/deletion polymorphism and atherosclerosis of vein grafts in Iranian patients, and characterize their clinical and demographic profile. METHODS: In this cross-sectional study, patients who underwent coronary artery bypass graft surgery more than five years ago, were included for angiographic analysis. Atherosclerosis was determined by quantitative angiography and adjusted Gensini score. The gene angiotensin converting enzyme I/D polymorphism was detected by polymerase chain reaction. RESULTS: A total of 102 patients participated in this study. Eighty-four patients were male. The frequency distribution of DD, ID and II polymorphism were 23.6%, 62.7% and 13.7% respectively. There were no differences among genotypic groups in age, sex, number of risk factors, number of vein grafts and months since bypass surgery. According to adjusted Gensini score [0.18±0.12 (II vs. 0.11±0.09 (ID and 0.1±0.09 (DD P=0.021] the II genotype was associated with severity of vein graft atherosclerosis. CONCLUSION: Although there are conflicting results about gene angiotensin converting enzyme I/D polymorphism and the degree of venous bypass graft degeneration, this study suggests an association between ACE genotype II and atherosclerosis of saphenous vein grafts, however, large samples considering clinical, demographic and ethnic profile are necessary to confirm these results.

Study on the correlation between KCNJ11 gene polymorphism and metabolic syndrome in the elderly.

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Jiang, Fan; Liu, Ning; Chen, Xiao Zhuang; Han, Kun Yuan; Zhu, Cai Zhong

2017-09-01

The aim of the study was to examine the correlation between KCNJ11 gene polymorphism and metabolic syndrome in elderly patients. From January 2014 to January 2015, 54 elderly patients with metabolic syndrome were enrolled in this study as the observation group. During the same period, 46 healthy elderly individuals were enrolled in this study as the control group. KCNJ11 gene polymorphism (rs28502) was analyzed using polymerase chain reaction-restriction fragment length polymorphism. The expression levels of mRNA in different genotypes were detected using FQ-PCR. ELISA was used to evaluate the KCNJ11 protein expression in different genotypes. KCNJ11 gene polymorphism and metabolic syndrome was studied by measuring the blood pressure levels in patients with different genotypes. Three genotypes of KCNJ11 gene in rs28502 were CC, CT and TT. The CC, CT and TT genotype frequencies in healthy population were 8.5, 9.2 and 82.2%, respectively, while the genotype frequencies in patients with metabolic syndrome were 42.4, 49.8 and 7.8%, respectively. There were significant differences between groups (P≤0.05). However, the genotype frequencies of C/T in healthy individuals and metabolic syndrome patients were 35.3 and 38.3%, respectively. There were no significant differences between groups (P>0.05). FQ-PCR results showed that the KCNJ11 mRNA expression levels in the control and observation groups had no significant differences (P>0.05). However, the results obtained from ELISA analysis revealed that KCNJ11 protein expression level in the observation group was significantly higher than that in the control group (Pmetabolic syndrome in the elderly. Elderly patients with the CC and TT genotypes are more likely to develop metabolic syndrome.

Application of a hierarchical enzyme classification method reveals the role of gut microbiome in human metabolism.

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Mohammed, Akram; Guda, Chittibabu

2015-01-01

Enzymes are known as the molecular machines that drive the metabolism of an organism; hence identification of the full enzyme complement of an organism is essential to build the metabolic blueprint of that species as well as to understand the interplay of multiple species in an ecosystem. Experimental characterization of the enzymatic reactions of all enzymes in a genome is a tedious and expensive task. The problem is more pronounced in the metagenomic samples where even the species are not adequately cultured or characterized. Enzymes encoded by the gut microbiota play an essential role in the host metabolism; thus, warranting the need to accurately identify and annotate the full enzyme complements of species in the genomic and metagenomic projects. To fulfill this need, we develop and apply a method called ECemble, an ensemble approach to identify enzymes and enzyme classes and study the human gut metabolic pathways. ECemble method uses an ensemble of machine-learning methods to accurately model and predict enzymes from protein sequences and also identifies the enzyme classes and subclasses at the finest resolution. A tenfold cross-validation result shows accuracy between 97 and 99% at different levels in the hierarchy of enzyme classification, which is superior to comparable methods. We applied ECemble to predict the entire complements of enzymes from ten sequenced proteomes including the human proteome. We also applied this method to predict enzymes encoded by the human gut microbiome from gut metagenomic samples, and to study the role played by the microbe-derived enzymes in the human metabolism. After mapping the known and predicted enzymes to canonical human pathways, we identified 48 pathways that have at least one bacteria-encoded enzyme, which demonstrates the complementary role of gut microbiome in human gut metabolism. These pathways are primarily involved in metabolizing dietary nutrients such as carbohydrates, amino acids, lipids, cofactors and

Application of a hierarchical enzyme classification method reveals the role of gut microbiome in human metabolism

Science.gov (United States)

2015-01-01

Background Enzymes are known as the molecular machines that drive the metabolism of an organism; hence identification of the full enzyme complement of an organism is essential to build the metabolic blueprint of that species as well as to understand the interplay of multiple species in an ecosystem. Experimental characterization of the enzymatic reactions of all enzymes in a genome is a tedious and expensive task. The problem is more pronounced in the metagenomic samples where even the species are not adequately cultured or characterized. Enzymes encoded by the gut microbiota play an essential role in the host metabolism; thus, warranting the need to accurately identify and annotate the full enzyme complements of species in the genomic and metagenomic projects. To fulfill this need, we develop and apply a method called ECemble, an ensemble approach to identify enzymes and enzyme classes and study the human gut metabolic pathways. Results ECemble method uses an ensemble of machine-learning methods to accurately model and predict enzymes from protein sequences and also identifies the enzyme classes and subclasses at the finest resolution. A tenfold cross-validation result shows accuracy between 97 and 99% at different levels in the hierarchy of enzyme classification, which is superior to comparable methods. We applied ECemble to predict the entire complements of enzymes from ten sequenced proteomes including the human proteome. We also applied this method to predict enzymes encoded by the human gut microbiome from gut metagenomic samples, and to study the role played by the microbe-derived enzymes in the human metabolism. After mapping the known and predicted enzymes to canonical human pathways, we identified 48 pathways that have at least one bacteria-encoded enzyme, which demonstrates the complementary role of gut microbiome in human gut metabolism. These pathways are primarily involved in metabolizing dietary nutrients such as carbohydrates, amino acids, lipids

Risk assessment: the importance of genetic polymorphisms in man

DEFF Research Database (Denmark)

Knudsen, Lisbeth E.; Loft, S H; Autrup, H

2001-01-01

and increased cancer risk, such results indicate effect modification regarding cancer risk. In risk assessment the safety 'factor' of 10 is generally accepted to allow for variation in individual susceptibility. Reviewing the literature justifies the factor of 10 when considering single polymorphisms. However......Many genetic polymorphisms in metabolism enzymes are important for the risk of cancer as shown in a large number of case-control studies. The relative risk estimates have shown large variations between such population studies. However, in most studies the relative risk estimates are in the range...

Sensor potency of the moonlighting enzyme-decorated cytoskeleton: the cytoskeleton as a metabolic sensor

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2013-01-01

Background There is extensive evidence for the interaction of metabolic enzymes with the eukaryotic cytoskeleton. The significance of these interactions is far from clear. Presentation of the hypothesis In the cytoskeletal integrative sensor hypothesis presented here, the cytoskeleton senses and integrates the general metabolic activity of the cell. This activity depends on the binding to the cytoskeleton of enzymes and, depending on the nature of the enzyme, this binding may occur if the enzyme is either active or inactive but not both. This enzyme-binding is further proposed to stabilize microtubules and microfilaments and to alter rates of GTP and ATP hydrolysis and their levels. Testing the hypothesis Evidence consistent with the cytoskeletal integrative sensor hypothesis is presented in the case of glycolysis. Several testable predictions are made. There should be a relationship between post-translational modifications of tubulin and of actin and their interaction with metabolic enzymes. Different conditions of cytoskeletal dynamics and enzyme-cytoskeleton binding should reveal significant differences in local and perhaps global levels and ratios of ATP and GTP. The different functions of moonlighting enzymes should depend on cytoskeletal binding. Implications of the hypothesis The physical and chemical effects arising from metabolic sensing by the cytoskeleton would have major consequences on cell shape, dynamics and cell cycle progression. The hypothesis provides a framework that helps the significance of the enzyme-decorated cytoskeleton be determined. PMID:23398642

Arsenic methylation capacity in relation to nutrient intake and genetic polymorphisms in one-carbon metabolism.

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Gamboa-Loira, Brenda; Hernández-Alcaraz, César; Gandolfi, A Jay; Cebrián, Mariano E; Burguete-García, Ana; García-Martínez, Angélica; López-Carrillo, Lizbeth

2018-07-01

Nutrients and genetic polymorphisms participating in one-carbon metabolism may explain interindividual differences in inorganic arsenic (iAs) methylation capacity, which in turn may account for variations in susceptibility to iAs-induced diseases. 1) To evaluate the association between polymorphisms in five one-carbon metabolism genes (FOLH1 c.223 T > C, MTHFD1 c.1958 G > A, MTHFR c.665 C > T, MTR c.2756 A > G, and MTRR c.66 A > G) and iAs methylation capacity; 2) To assess if previously reported associations between nutrient intake and iAs methylation capacity are modified by those polymorphisms. Women (n = 1027) exposed to iAs in Northern Mexico were interviewed. Blood and urine samples were collected. Nutrient dietary intake was estimated using a validated food frequency questionnaire. iAs methylation capacity was calculated from urinary iAs species (iAs, monomethylarsonic acid [MMA] and dimethylarsinic acid [DMA]) measured by high performance liquid chromatography (HPLC-ICP-MS). One polymorphism in each of the five genes evaluated was genotyped by allelic discrimination. Multivariable linear regression models were used to evaluate if genetic polymorphisms modified the associations between iAs methylation capacity parameters and nutrient intake. The median (min-max) concentration of total arsenic (TAs) was 20.2 (1.3-2776.0) µg/g creatinine in the study population. Significant interactions for iAs metabolism were only found with FOLH1 c.223 T > C polymorphism and vitamin B12 intake, so that CT and CC genotype carriers had significantly lower %iAs, and higher DMA/iAs with an increased vitamin B12 intake, as compared to carriers of wild-type TT. Differences in dietary nutrient intake and genetic variants in one-carbon metabolism may jointly influence iAs methylation capacity. Confirmation of these interactions in other populations is warranted. Copyright © 2018 Elsevier Inc. All rights reserved.

Association of HMOX1 and NQO1 Polymorphisms with Metabolic Syndrome Components.

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Angélica Martínez-Hernández

Full Text Available Metabolic syndrome (MetS is among the most important public health problems worldwide, and is recognized as a major risk factor for various illnesses, including type 2 diabetes mellitus, obesity, and cardiovascular diseases. Recently, oxidative stress has been suggested as part of MetS aetiology. The heme oxygenase 1 (HMOX1 and NADH:quinone oxidoreductase 1 (NQO1 genes are crucial mediators of cellular defence against oxidative stress. In the present study, we analysed the associations of HMOX1 (GTn and NQO1 C609T polymorphisms with MetS and its components. Our study population comprised 735 Mexican Mestizos unrelated volunteers recruited from different tertiary health institutions from Mexico City. In order to know the HMOX1 (GTn and NQO1 C609T allele frequencies in Amerindians, we included a population of 241 Amerindian native speakers. Their clinical and demographic data were recorded. The HMOX1 (GTn polymorphism was genotyped using PCR and fluorescence technology. NQO1 C609T polymorphism genotyping was performed using TaqMan probes. Short allele (<25 GT repeats of the HMOX1 polymorphism was associated with high systolic and diastolic blood pressure, and the T allele of the NQO1 C609T polymorphism was associated with increased triglyceride levels and decreased HDL-c levels, but only in individuals with MetS. This is the first study to analyse the association between MetS and genes involved in oxidative stress among Mexican Mestizos. Our data suggest that polymorphisms of HMOX1 and NQO1 genes are associated with a high risk of metabolic disorders, including high systolic and diastolic blood pressure, hypertriglyceridemia, and low HDL-c levels in Mexican Mestizo individuals.

Altered drug metabolism during pregnancy: hormonal regulation of drug-metabolizing enzymes.

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Jeong, Hyunyoung

2010-06-01

Medication use during pregnancy is prevalent, but pharmacokinetic information of most drugs used during pregnancy is lacking in spite of known effects of pregnancy on drug disposition. Accurate pharmacokinetic information is essential for optimal drug therapy in mother and fetus. Thus, understanding how pregnancy influences drug disposition is important for better prediction of pharmacokinetic changes of drugs in pregnant women. Pregnancy is known to affect hepatic drug metabolism, but the underlying mechanisms remain unknown. Physiological changes accompanying pregnancy are probably responsible for the reported alteration in drug metabolism during pregnancy. These include elevated concentrations of various hormones such as estrogen, progesterone, placental growth hormones and prolactin. This review covers how these hormones influence expression of drug-metabolizing enzymes (DMEs), thus potentially responsible for altered drug metabolism during pregnancy. The reader will gain a greater understanding of the altered drug metabolism in pregnant women and the regulatory effects of pregnancy hormones on expression of DMEs. In-depth studies in hormonal regulatory mechanisms as well as confirmatory studies in pregnant women are warranted for systematic understanding and prediction of the changes in hepatic drug metabolism during pregnancy.

Characterization of the human cytochrome P450 enzymes involved in the metabolism of dihydrocodeine

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Kirkwood, L. C.; Nation, R. L.; Somogyi, A. A.

1997-01-01

Aims Using human liver microsomes from donors of the CYP2D6 poor and extensive metabolizer genotypes, the role of individual cytochromes P-450 in the oxidative metabolism of dihydrocodeine was investigated. Methods The kinetics of formation of N- and O-demethylated metabolites, nordihydrocodeine and dihydromorphine, were determined using microsomes from six extensive and one poor metabolizer and the effects of chemical inhibitors selective for individual P-450 enzymes of the 1A, 2A, 2C, 2D, 2E and 3A families and of LKM1 (anti-CYP2D6) antibodies were studied. Results Nordihydrocodeine was the major metabolite in both poor and extensive metabolizers. Kinetic constants for N-demethylation derived from the single enzyme Michaelis-Menten model did not differ between the two groups. Troleandomycin and erythromycin selectively inhibited N-demethylation in both extensive and poor metabolizers. The CYP3A inducer, α-naphthoflavone, increased N-demethylation rates. The kinetics of formation of dihydromorphine in both groups were best described by a single enzyme Michaelis-Menten model although inhibition studies in extensive metabolizers suggested involvement of two enzymes with similar Km values. The kinetic constants for O-demethylation were significantly different in extensive and poor metabolizers. The extensive metabolizers had a mean intrinsic clearance to dihydromorphine more than ten times greater than the poor metabolizer. The CYP2D6 chemical inhibitors, quinidine and quinine, and LKM1 antibodies inhibited O-demethylation in extensive metabolizers; no effect was observed in microsomes from a poor metabolizer. Conclusions CYP2D6 is the major enzyme mediating O-demethylation of dihydrocodeine to dihydromorphine. In contrast, nordihydrocodeine formation is predominantly catalysed by CYP3A. PMID:9431830

Metabolic Diseases Downregulate the Majority of Histone Modification Enzymes, Making a Few Upregulated Enzymes Novel Therapeutic Targets--"Sand Out and Gold Stays".

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Shao, Ying; Chernaya, Valeria; Johnson, Candice; Yang, William Y; Cueto, Ramon; Sha, Xiaojin; Zhang, Yi; Qin, Xuebin; Sun, Jianxin; Choi, Eric T; Wang, Hong; Yang, Xiao-feng

2016-02-01

To determine whether the expression of histone modification enzymes is regulated in physiological and pathological conditions, we took an experimental database mining approach pioneered in our labs to determine a panoramic expression profile of 164 enzymes in 19 human and 17 murine tissues. We have made the following significant findings: (1) Histone enzymes are differentially expressed in cardiovascular, immune, and other tissues; (2) our new pyramid model showed that heart and T cells are among a few tissues in which histone acetylation/deacetylation, and histone methylation/demethylation are in the highest varieties; and (3) histone enzymes are more downregulated than upregulated in metabolic diseases and regulatory T cell (Treg) polarization/ differentiation, but not in tumors. These results have demonstrated a new working model of "Sand out and Gold stays," where more downregulation than upregulation of histone enzymes in metabolic diseases makes a few upregulated enzymes the potential novel therapeutic targets in metabolic diseases and Treg activity.

Association of glucocorticoid receptor polymorphisms with clinical and metabolic profiles in polycystic ovary syndrome

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Gustavo A.Rosa Maciel

2014-03-01

Full Text Available OBJECTIVES: We aimed to investigate whether glucocorticoid receptor gene polymorphisms are associated with clinical and metabolic profiles in patients with polycystic ovary syndrome. Polycystic ovary syndrome is a complex endocrine disease that affects 5-8% of women and may be associated with metabolic syndrome, which is a risk factor for cardiovascular disease. Cortisol action and dysregulation account for metabolic syndrome development in the general population. As glucocorticoid receptor gene (NR3C1 polymorphisms regulate cortisol sensitivity, we hypothesized that variants of this gene may be involved in the adverse metabolic profiles of patients with polycystic ovary syndrome. METHOD: Clinical, metabolic and hormonal profiles were evaluated in 97 patients with polycystic ovary syndrome who were diagnosed according to the Rotterdam criteria. The alleles of the glucocorticoid gene were genotyped. Association analyses were performed using the appropriate statistical tests. RESULTS: Obesity and metabolic syndrome were observed in 42.3% and 26.8% of patients, respectively. Body mass index was positively correlated with blood pressure, triglyceride, LDL-c, total cholesterol, glucose and insulin levels as well as HOMA-IR values and inversely correlated with HDL-c and SHBG levels. The BclI and A3669G variants were found in 24.7% and 13.4% of alleles, respectively. BclI carriers presented a lower frequency of insulin resistance compared with wild-type subjects. CONCLUSION: The BclI variant is associated with a lower frequency of insulin resistance in women with polycystic ovary syndrome. Glucocorticoid gene polymorphism screening during treatment of the syndrome may be useful for identifying subgroups of at-risk patients who would benefit the most from personalized treatment.

Polymorphism of antibiotic-inactivating enzyme driven by ecology expands the environmental resistome.

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Kim, Dae-Wi; Thawng, Cung Nawl; Choi, Jung-Hye; Lee, Kihyun; Cha, Chang-Jun

2018-01-01

The environmental resistome has been recognized as the origin and reservoir of antibiotic resistance genes and considered to be dynamic and ever expanding. In this study, a targeted gene sequencing approach revealed that the polymorphic diversity of the aminoglycoside-inactivating enzyme AAC(6')-Ib was ecological niche-specific. AAC(6')-Ib-cr, previously known as a clinical variant, was prevalent in various soils and the intestines of chickens and humans, suggesting that this variant might not have arisen from adaptive mutations in the clinic but instead originated from the environment. Furthermore, ecologically dominant polymorphic variants of AAC(6')-Ib were characterized and found to display different substrate specificities for quinolones and aminoglycosides, conferring the altered resistance spectra. Interestingly, a novel variant with the D179Y substitution showed an extended resistance spectrum to the recently developed fluoroquinolone gemifloxacin. Our results suggest that soil and animal microbiomes could be major reservoirs of antibiotic resistance; polymorphic diversity expands the antibiotic resistome in the environment, resulting in the potential emergence of novel resistance.

Association of HMOX1 and NQO1 Polymorphisms with Metabolic Syndrome Components.

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Martínez-Hernández, Angélica; Córdova, Emilio J; Rosillo-Salazar, Oscar; García-Ortíz, Humberto; Contreras-Cubas, Cecilia; Islas-Andrade, Sergio; Revilla-Monsalve, Cristina; Salas-Labadía, Consuelo; Orozco, Lorena

2015-01-01

Metabolic syndrome (MetS) is among the most important public health problems worldwide, and is recognized as a major risk factor for various illnesses, including type 2 diabetes mellitus, obesity, and cardiovascular diseases. Recently, oxidative stress has been suggested as part of MetS aetiology. The heme oxygenase 1 (HMOX1) and NADH:quinone oxidoreductase 1 (NQO1) genes are crucial mediators of cellular defence against oxidative stress. In the present study, we analysed the associations of HMOX1 (GT)n and NQO1 C609T polymorphisms with MetS and its components. Our study population comprised 735 Mexican Mestizos unrelated volunteers recruited from different tertiary health institutions from Mexico City. In order to know the HMOX1 (GT)n and NQO1 C609T allele frequencies in Amerindians, we included a population of 241 Amerindian native speakers. Their clinical and demographic data were recorded. The HMOX1 (GT)n polymorphism was genotyped using PCR and fluorescence technology. NQO1 C609T polymorphism genotyping was performed using TaqMan probes. Short allele (metabolic disorders, including high systolic and diastolic blood pressure, hypertriglyceridemia, and low HDL-c levels in Mexican Mestizo individuals.

PPARγ Pro12Ala and ACE ID polymorphisms are associated with BMI and fat distribution, but not metabolic syndrome

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Passaro Angela

2011-12-01

Full Text Available Abstract Background Metabolic Syndrome (MetS results from the combined effect of environmental and genetic factors. We investigated the possible association of peroxisome proliferator-activated receptor-γ2 (PPARγ2 Pro12Ala and Angiotensin Converting Enzyme (ACE I/D polymorphisms with MetS and interaction between these genetic variants. Methods Three hundred sixty four unrelated Caucasian subjects were enrolled. Waist circumference, blood pressure, and body mass index (BMI were recorded. Body composition was estimated by impedance analysis; MetS was diagnosed by the NCEP-ATPIII criteria. A fasting blood sample was obtained for glucose, insulin, lipid profile determination, and DNA isolation for genotyping. Results The prevalence of MetS did not differ across PPARγ2 or ACE polymorphisms. Carriers of PPARγ2 Ala allele had higher BMI and fat-mass but lower systolic blood pressure compared with Pro/Pro homozygotes. A significant PPARγ2 gene-gender interaction was observed in the modulation of BMI, fat mass, and blood pressure, with significant associations found in women only. A PPARγ2-ACE risk genotype combination for BMI and fat mass was found, with ACE DD/PPARγ2 Ala subjects having a higher BMI (p = 0.002 and Fat Mass (p = 0.002. Pro12Ala was independently associated with waist circumference independent of BMI and gender. Conclusions Carriers of PPARγ2 Ala allele had higher BMI and fat-mass but not a worse metabolic profile, possibly because of a more favorable adipose tissue distribution. A gene interaction exists between Pro12Ala and ACE I/D on BMI and fat mass. Further studies are needed to assess the contribution of Pro12Ala polymorphism in adiposity distribution.

ALK7 Gene Polymorphism is Associated with Metabolic Syndrome Risk and Cardiovascular Remodeling

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Zhang, Wenchao; Wang, Hui; Zhang, Wei [Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education and Chinese Ministry of Public Health, Qilu Hospital of Shandong University, Jinan (China); Lv, Ruijuan [Department of Emergency, Qilu Hospital of Shandong University, Jinan (China); Wang, Zhihao [Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education and Chinese Ministry of Public Health, Qilu Hospital of Shandong University, Jinan (China); Department of Geriatrics, Qilu Hospital of Shandong University, Jinan (China); Shang, Yuanyuan; Zhang, Yun; Zhong, Ming [Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education and Chinese Ministry of Public Health, Qilu Hospital of Shandong University, Jinan (China); Chen, Yuguo; Tang, Mengxiong, E-mail: tangmengxiongsdu8@163.com [Key Laboratory of Cardiovascular Remodeling and Function Research Chinese Ministry of Education and Chinese Ministry of Public Health, Qilu Hospital of Shandong University, Jinan (China); Department of Emergency, Qilu Hospital of Shandong University, Jinan (China)

2013-08-15

Activin receptor-like kinase 7 (ALK7) is a type I receptor for the TGF-β superfamily and has recently been demonstrated to play an important role in the maintenance of metabolic homeostasis. To investigate the association of the ALK7 gene polymorphism with metabolic syndrome (MetS) and cardiovascular remodeling in MetS patients. The single nucleotide polymorphism rs13010956 in the ALK7 gene was genotyped in 351 Chinese subjects undergoing carotid and cardiac ultrasonography. The associations of the ALK7 gene polymorphism with the MetS phenotype, MetS parameters, and cardiovascular ultrasonic features were analyzed. The rs13010956 polymorphism in the ALK7 gene was found to be significantly associated with the MetS phenotype in females (p < 0.05) and was also significantly associated with blood pressure in the total (p < 0.05) and female populations (p < 0.01). Further analysis revealed that rs13010956 was associated with mean intima-media thickness of the carotid arteries in females (p < 0.05). After control for body mass index, blood pressure, fasting blood glucose, and triglycerides, rs13010956 was also found to be significantly associated with left ventricular mass index in the total (p < 0.05) and female populations (p < 0.05). Our findings suggested that the ALK7 gene polymorphism rs13010956 was significantly associated with MetS risk in females and may be involved in cardiovascular remodeling in MetS patients.

ALK7 Gene Polymorphism is Associated with Metabolic Syndrome Risk and Cardiovascular Remodeling

International Nuclear Information System (INIS)

Zhang, Wenchao; Wang, Hui; Zhang, Wei; Lv, Ruijuan; Wang, Zhihao; Shang, Yuanyuan; Zhang, Yun; Zhong, Ming; Chen, Yuguo; Tang, Mengxiong

2013-01-01

Activin receptor-like kinase 7 (ALK7) is a type I receptor for the TGF-β superfamily and has recently been demonstrated to play an important role in the maintenance of metabolic homeostasis. To investigate the association of the ALK7 gene polymorphism with metabolic syndrome (MetS) and cardiovascular remodeling in MetS patients. The single nucleotide polymorphism rs13010956 in the ALK7 gene was genotyped in 351 Chinese subjects undergoing carotid and cardiac ultrasonography. The associations of the ALK7 gene polymorphism with the MetS phenotype, MetS parameters, and cardiovascular ultrasonic features were analyzed. The rs13010956 polymorphism in the ALK7 gene was found to be significantly associated with the MetS phenotype in females (p < 0.05) and was also significantly associated with blood pressure in the total (p < 0.05) and female populations (p < 0.01). Further analysis revealed that rs13010956 was associated with mean intima-media thickness of the carotid arteries in females (p < 0.05). After control for body mass index, blood pressure, fasting blood glucose, and triglycerides, rs13010956 was also found to be significantly associated with left ventricular mass index in the total (p < 0.05) and female populations (p < 0.05). Our findings suggested that the ALK7 gene polymorphism rs13010956 was significantly associated with MetS risk in females and may be involved in cardiovascular remodeling in MetS patients

Dextromethorphan and debrisoquine metabolism and polymorphism of the gene for cytochrome P450 isozyme 2D50 in Thoroughbreds.

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Corado, Carley R; McKemie, Daniel S; Knych, Heather K

2016-09-01

OBJECTIVE To characterize polymorphisms of the gene for cytochrome P450 isozyme 2D50 (CYP2D50) and the disposition of 2 CYP2D50 probe drugs, dextromethorphan and debrisoquine, in horses. ANIMALS 23 healthy horses (22 Thoroughbreds and 1 Standardbred). PROCEDURES Single-nucleotide polymorphisms (SNPs) in CYP2D50 were identified. Disposition of dextromethorphan (2 mg/kg) and debrisoquine (0.2 mg/kg) were determined after oral (dextromethorphan) or nasogastric (debrisoquine) administration to the horses. Metabolic ratios of plasma dextromethorphan and total dextrorphan (dextrorphan plus dextrorphan-O-β-glucuronide) and 4-hydroxydebrisoquine concentrations were calculated on the basis of the area under the plasma concentration-versus-time curve extrapolated to infinity for the parent drug divided by that for the corresponding metabolite. Pharmacokinetic data were used to categorize horses into the phenotypic drug-metabolism categories poor, extensive, and ultrarapid. Disposition patterns were compared among categories, and relationships between SNPs and metabolism categories were explored. RESULTS Gene sequencing identified 51 SNPs, including 27 nonsynonymous SNPs. Debrisoquine was minimally detected after oral administration. Disposition of dextromethorphan varied markedly among horses. Metabolic ratios for dextromethorphan ranged from 0.03 to 0.46 (mean, 0.12). On the basis of these data, 1 horse was characterized as a poor metabolizer, 18 were characterized as extensive metabolizers, and 3 were characterized as ultrarapid metabolizers. CONCLUSIONS AND CLINICAL RELEVANCE Findings suggested that CYP2D50 is polymorphic and that the disposition of the probe drug varies markedly in horses. The polymorphisms may be related to rates of drug metabolism. Additional research involving more horses of various breeds is needed to fully explore the functional implication of polymorphisms in CYP2D50.

Liver enzymes and markers of inflammation in Nigerian adults with metabolic syndrome

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Udenze Ifeoma Christiana

2015-01-01

Full Text Available Aims and objectives: The aim of this study is to determine the plasma levels of the liver enzymes alanine aminotransferase (ALT, aspartate aminotransferase (AST, alkaline phosphatase (ALP, gamma-glutamyl transferase (GGT, and lactate dehydrogenase (LDH in people with metabolic syndrome and to determine the association between the liver enzymes and obesity, insulin resistance, interleukin 6 (IL-6, and C-reactive protein (CRP in adult Nigerians with metabolic syndrome. Materials and Methods: This was a case control study of 50 adult men and women with metabolic syndrome, and 50 age- and sex-matched males and females without metabolic syndrome. Metabolic syndrome was defined based on the National Cholesterol Education Program (NCEP-Adult Treatment Panel III (ATPIII criteria. Written informed consent was obtained from the participants. Sociodemographic and clinical data were collected using a structured questionnaire. Venous blood was collected after an overnight fast. The ethics committee of the Lagos University Teaching Hospital in Lagos, Nigeria, approved the study protocol. Comparison of continuous variables was done using the student′s t-test. Regression and correlation analysis were used to determine the associations between variables. Statistical significance was set at P < 0.05. Results: There was a statistically significant increase in the liver enzymes ALP (P = 0.031, ALT (P = 0.019, and GGT (P = 0.037, as well as in the inflammatory markers CRP (P = 0.019 and the cytokine IL-6 (P = 0.040 between the two study groups. ALP and ALT showed significant correlation with waist circumference, BMI, fasting insulin, and waist/hip ratio (P < 0.05. Multivariate regression also identified ALT, AST, and ALP to be associated with IL-6 and CRP (P < 0.05. Conclusion: Liver enzyme levels were increased in metabolic syndrome and associated with obesity, fasting insulin, and CRP. Elevated liver enzymes may indicate dysmetabolism and increased

Methanol Metabolism in Yeasts : Regulation of the Synthesis of Catabolic Enzymes

NARCIS (Netherlands)

Egli, Th.; Dijken, J.P. van; Veenhuis, M.; Harder, W.; Fiechter, A.

1980-01-01

The regulation of the synthesis of four dissimilatory enzymes involved in methanol metabolism, namely alcohol oxidase, formaldehyde dehydrogenase, formate dehydrogenase and catalase was investigated in the yeasts Hansenula polymorpha and Kloeckera sp. 2201. Enzyme profiles in cell-free extracts of

A systems biology framework for modeling metabolic enzyme inhibition of Mycobacterium tuberculosis

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Reifman Jaques

2009-09-01

Full Text Available Abstract Background Because metabolism is fundamental in sustaining microbial life, drugs that target pathogen-specific metabolic enzymes and pathways can be very effective. In particular, the metabolic challenges faced by intracellular pathogens, such as Mycobacterium tuberculosis, residing in the infected host provide novel opportunities for therapeutic intervention. Results We developed a mathematical framework to simulate the effects on the growth of a pathogen when enzymes in its metabolic pathways are inhibited. Combining detailed models of enzyme kinetics, a complete metabolic network description as modeled by flux balance analysis, and a dynamic cell population growth model, we quantitatively modeled and predicted the dose-response of the 3-nitropropionate inhibitor on the growth of M. tuberculosis in a medium whose carbon source was restricted to fatty acids, and that of the 5'-O-(N-salicylsulfamoyl adenosine inhibitor in a medium with low-iron concentration. Conclusion The predicted results quantitatively reproduced the experimentally measured dose-response curves, ranging over three orders of magnitude in inhibitor concentration. Thus, by allowing for detailed specifications of the underlying enzymatic kinetics, metabolic reactions/constraints, and growth media, our model captured the essential chemical and biological factors that determine the effects of drug inhibition on in vitro growth of M. tuberculosis cells.

Advances in drug metabolism and pharmacogenetics research in Australia.

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Mackenzie, Peter I; Somogyi, Andrew A; Miners, John O

2017-02-01

Metabolism facilitates the elimination, detoxification and excretion in urine or bile (as biotransformation products) of a myriad of structurally diverse drugs and other chemicals. The metabolism of drugs, non-drug xenobiotics and many endogenous compounds is catalyzed by families of drug metabolizing enzymes (DMEs). These include the hemoprotein-containing cytochromes P450, which function predominantly as monooxygenases, and conjugation enzymes that transfer a sugar, sulfate, acetate or glutathione moiety to substrates containing a suitable acceptor functional group. Drug and chemical metabolism, especially the enzymes that catalyse these reactions, has been the research focus of several groups in Australia for over four decades. In this review, we highlight the role of recent and current drug metabolism research in Australia, including elucidation of the structure and function of enzymes from the various DME families, factors that modulate enzyme activity in humans (e.g. drug-drug interactions, gene expression and genetic polymorphism) and the application of in vitro approaches for the prediction of drug metabolism parameters in humans, along with the broader pharmacological/clinical pharmacological and toxicological significance of drug metabolism and DMEs and their relevance to drug discovery and development, and to clinical practice. Copyright © 2016 Elsevier Ltd. All rights reserved.

Roles of Beta2- and Beta3-Adrenoceptor Polymorphisms in Hypertension and Metabolic Syndrome

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Kazuko Masuo

2010-01-01

gain, and the sympathetic nervous system participates in regulating energy balance through thermogenesis. The thermogenic effects of catecholamines in obesity have been mainly mediated via the 2- and 3-adrenergic receptors in humans. Further, 2-adrenoceptors importantly influence vascular reactivity and may regulate blood pressure. Genetic polymorphistns of the -adrenoceptor gene have been shown to alter the function of several adrenoceptor subtypes and thus to modify the response to catecholamine. 2-adrenoceptor polymorphisms (Arg16Gly, Gln27Glu, and Thr164Ile have been studied in relation to hypertension. Genetic variations in the 3-adrenoceptor (i.e. Try64Arg variant are also associated with both obesity and hypertension. However, the precise relationships of the polymorphisms of 2- and 3-adrenoceptor genes with sympathetic nervous system activity, hypertension, and metabolic syndrome have not been fully clarified. This paper will discuss the current topics involving the influence of the sympathetic nervous system and 2- and 3- adrenoceptor polymorphisms in hypertension and metabolic syndrome.

METABOLIC MAPPING BY ENZYME HISTOCHEMISTRY IN LIVING ANIMALS, TISSUES AND CELLS

NARCIS (Netherlands)

van Noorden, C. J. F.

2009-01-01

Imaging of reporter molecules such as fluorescent proteins in intact animals, tissue and cells has become an indispensable tool in cell biology Imaging activity of enzymes, which is called metabolic mapping, provides information on subcellular localisation in combination with function of the enzymes

Genetic polymorphisms in antioxidative enzymes are associated to FEV(1) in smokers independently of asthma

DEFF Research Database (Denmark)

Malling, T H; Sigsgaard, Torben; Andersen, Charlotte Brasch

2012-01-01

), GSTT1 (gene copy number), and GSTM1 (gene copy number). We found no associations between these genotypes and the asthma phenotypes. For the 201 subjects identified as current smokers and recruited via random sampling, an association was seen between increasing number of genotypes coding for high...... of genotypes coding for low antioxidative enzyme activity. The present study does not support the hypothesis that asthma is associated with genotypes of these major antioxidative enzymes. However, we speculate that since we see an impact of these genotypes on lung function in young adult smokers, polymorphisms...... in antioxidative enzymes may contribute to the range of susceptibility of smokers have to COPD....

Expression and Regulation of Drug Transporters and Metabolizing Enzymes in the Human Gastrointestinal Tract.

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Drozdzik, M; Oswald, S

2016-01-01

Orally administered drugs must pass through the intestinal wall and then through the liver before reaching systemic circulation. During this process drugs are subjected to different processes that may determine the therapeutic value. The intestinal barrier with active drug metabolizing enzymes and drug transporters in enterocytes plays an important role in the determination of drug bioavailability. Accumulating information demonstrates variable distribution of drug metabolizing enzymes and transporters along the human gastrointestinal tract (GI), that creates specific barrier characteristics in different segments of the GI. In this review, expression of drug metabolizing enzymes and transporters in the healthy and diseased human GI as well as their regulatory aspects: genetic, miRNA, DNA methylation are outlined. The knowledge of unique interplay between drug metabolizing enzymes and transporters in specific segments of the GI tract allows more precise definition of drug release sites within the GI in order to assure more complete bioavailability and prediction of drug interactions.

Human TP53 polymorphism (rs1042522) modelled in mouse does not affect glucose metabolism and body composition.

Science.gov (United States)

Reiling, Erwin; Speksnijder, Ewoud N; Pronk, Amanda C M; van den Berg, Sjoerd A A; Neggers, Silvia J W; Rietbroek, Ilma; van Steeg, Harry; Dollé, Martijn E T

2014-02-13

Variation in TP53 has been associated with cancer. The pro-allele of a TP53 polymorphism in codon 72 (rs1042522) has been associated with longevity. Recently, we showed that the same allele might be involved in preservation of glucose metabolism, body composition and blood pressure during ageing. Here, we assessed glucose tolerance and body composition in mice carrying the human polymorphism. Our data do not support the previous findings in humans, suggesting that this polymorphism does not play a major role in development of glucose metabolism and body composition during ageing. Alternatively, the mouse model may not be suitable to validate these rs1042522-associated traits up to the age tested.

Enzymes and Inhibitors in Neonicotinoid Insecticide Metabolism

Science.gov (United States)

Shi, Xueyan; Dick, Ryan A.; Ford, Kevin A.; Casida, John E.

2009-01-01

Neonicotinoid insecticide metabolism involves considerable substrate specificity and regioselectivity of the relevant CYP450, aldehyde oxidase, and phase II enzymes. Human CYP450 recombinant enzymes carry out the following conversions: CYP3A4, 2C19 and 2B6 for thiamethoxam (TMX) to clothianidin (CLO); 3A4, 2C19 and 2A6 for CLO to desmethyl-CLO; 2C19 for TMX to desmethyl-TMX. Human liver aldehyde oxidase reduces the nitro substituent of CLO to nitroso much more rapidly than that of TMX. Imidacloprid (IMI), CLO and several of their metabolites do not give detectable N-glucuronides but 5-hydroxy-IMI, 4,5-diol-IMI and 4-hydroxy-thiacloprid are converted to O-glucuronides in vitro with mouse liver microsomes and UDP-glucuronic acid or in vivo in mice. Mouse liver cytosol with S-adenosylmethionine converts desmethyl-CLO to CLO but not desmethyl-TMX to TMX. Two organophosphorus CYP450 inhibitors partially block IMI, thiacloprid and CLO metabolism in vivo in mice, elevating the brain and liver levels of the parent compounds while reducing amounts of the hydroxylated metabolites. PMID:19391582

Metabolic enzyme cost explains variable trade-offs between microbial growth rate and yield.

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Meike T Wortel

2018-02-01

Full Text Available Microbes may maximize the number of daughter cells per time or per amount of nutrients consumed. These two strategies correspond, respectively, to the use of enzyme-efficient or substrate-efficient metabolic pathways. In reality, fast growth is often associated with wasteful, yield-inefficient metabolism, and a general thermodynamic trade-off between growth rate and biomass yield has been proposed to explain this. We studied growth rate/yield trade-offs by using a novel modeling framework, Enzyme-Flux Cost Minimization (EFCM and by assuming that the growth rate depends directly on the enzyme investment per rate of biomass production. In a comprehensive mathematical model of core metabolism in E. coli, we screened all elementary flux modes leading to cell synthesis, characterized them by the growth rates and yields they provide, and studied the shape of the resulting rate/yield Pareto front. By varying the model parameters, we found that the rate/yield trade-off is not universal, but depends on metabolic kinetics and environmental conditions. A prominent trade-off emerges under oxygen-limited growth, where yield-inefficient pathways support a 2-to-3 times higher growth rate than yield-efficient pathways. EFCM can be widely used to predict optimal metabolic states and growth rates under varying nutrient levels, perturbations of enzyme parameters, and single or multiple gene knockouts.

Association of the Pro12Ala Polymorphism with the Metabolic Parameters in Women with Polycystic Ovary Syndrome

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Moushira Zaki

2017-06-01

CONCLUSION: The PPARG Pro12Ala polymorphism might contribute to the risk of PCOS and abnormal metabolic parameters and could be considered as a biomarker for early diagnosis and clinic prediction of metabolic complications.

Angiotensin-converting enzyme activity in Cavalier King Charles Spaniels with an ACE gene polymorphism and myxomatous mitral valve disease.

Science.gov (United States)

Meurs, Kathryn M; Olsen, Lisbeth H; Reimann, Maria J; Keene, Bruce W; Atkins, Clarke E; Adin, Darcy; Aona, Brent; Condit, Julia; DeFrancesco, Teresa; Reina-Doreste, Yamir; Stern, Joshua A; Tou, Sandra; Ward, Jessica; Woodruff, Kathleen

2018-02-01

Myxomatous mitral valve disease (MMVD) is the most common heart disease in the dog. It is particularly common in the Cavalier King Charles Spaniel (CKCS) breed and affected dogs are frequently managed with angiotensin-converting enzyme inhibitors (ACE-I). We have previously identified a canine ACE gene polymorphism associated with a decrease in angiotensin-converting enzyme (ACE) activity. The aim of this study was to evaluate for the prevalence of the ACE polymorphism in CKCS with mitral valve disease and to determine whether the presence of the polymorphism is associated with alterations in ACE activity at different stages of cardiac disease. Seventy-three dogs with a diagnosis of mitral valve disease were evaluated and a blood sample was drawn for ACE polymorphism genotyping and ACE activity measurement. Forty-three dogs were homozygous for the ACE polymorphism; five were heterozygous and 25 were homozygous wild type. The mean age and the median severity of disease were not different for dogs with the polymorphism and dogs with the wild-type sequence. The median baseline ACE activity was significantly lower for the ACE polymorphism (27.0 U/l) than the wild-type sequence dogs (31.0 U/l) (P=0.02). Dogs with more severe disease and the ACE polymorphism had significantly lower levels of ACE activity than dogs with the wild-type sequence (P=0.03). The CKCS appears to have a high prevalence of the ACE variant. Dogs with the ACE variant had lower levels of ACE activity even in more advanced mitral valve disease than dogs without the variant. The clinical significance of this finding and its impact on the need for ACE-I in dogs with the polymorphism and heart disease deserves further study.

Radiation Exposure Alters Expression of Metabolic Enzyme Genes in Mice

Science.gov (United States)

Wotring, V. E.; Mangala, L. S.; Zhang, Y.; Wu, H.

2011-01-01

Most administered pharmaceuticals are metabolized by the liver. The health of the liver, especially the rate of its metabolic enzymes, determines the concentration of circulating drugs as well as the duration of their efficacy. Most pharmaceuticals are metabolized by the liver, and clinically-used medication doses are given with normal liver function in mind. A drug overdose can result in the case of a liver that is damaged and removing pharmaceuticals from the circulation at a rate slower than normal. Alternatively, if liver function is elevated and removing drugs from the system more quickly than usual, it would be as if too little drug had been given for effective treatment. Because of the importance of the liver in drug metabolism, we want to understand the effects of spaceflight on the enzymes of the liver and exposure to cosmic radiation is one aspect of spaceflight that can be modeled in ground experiments. Additionally, it has been previous noted that pre-exposure to small radiation doses seems to confer protection against later and larger radiation doses. This protective power of pre-exposure has been called a priming effect or radioadaptation. This study is an effort to examine the drug metabolizing effects of radioadaptation mechanisms that may be triggered by early exposure to low radiation doses.

Development of radiometric assays for quantification of enzyme activities of the key enzymes of thyroid hormones metabolism

Czech Academy of Sciences Publication Activity Database

Pavelka, Stanislav

2014-01-01

Roč. 63, Suppl.1 (2014), S133-S140 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) 7AMB12SK158; GA ČR(CZ) GA304/08/0256 Institutional support: RVO:67985823 Keywords : enzyme * metabolism * radiometric assay * thyroid hormone Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 1.293, year: 2014

Metabolic Diseases Downregulate the Majority of Histone Modification Enzymes, Making a Few Upregulated Enzymes Novel Therapeutic Targets – “Sand out and Gold Stays”

Science.gov (United States)

Shao, Ying; Chernaya, Valeria; Johnson, Candice; Yang, William Y.; Cueto, Ramon; Sha, Xiaojin; Zhang, Yi; Qin, Xuebin; Sun, Jianxin; Choi, Eric T.; Wang, Hong; Yang, Xiao-feng

2016-01-01

To determine whether the expression of histone modification enzymes is regulated in physiological and pathological conditions, we took an experimental database mining approach pioneered in our labs to determine a panoramic expression profile of 164 enzymes in 19 human and 17 murine tissues. We have made the following significant findings: 1) Histone enzymes are differentially expressed in cardiovascular, immune and other tissues; 2) Our new pyramid model showed that heart and T cells are among a few tissues in which histone acetylation/deacetylation, histone methylation/demethylation are in the highest varieties; and 3) Histone enzymes are more downregulated than upregulated in metabolic diseases and Treg polarization/differentiation, but not in tumors. These results have demonstrated a new working model of “sand out and gold stays,” where more downregulation than upregulation of histone enzymes in metabolic diseases makes a few upregulated enzymes the potential novel therapeutic targets in metabolic diseases and Treg activity. PMID:26746407

Beyond triglyceride synthesis: the dynamic functional roles of MGAT and DGAT enzymes in energy metabolism.

Science.gov (United States)

Shi, Yuguang; Cheng, Dong

2009-07-01

Monoacyglycerol acyltransferases (MGATs) and diacylglycerol acyltransferases (DGATs) catalyze two consecutive steps of enzyme reactions in the synthesis of triacylglycerols (TAGs). The metabolic complexity of TAG synthesis is reflected by the presence of multiple isoforms of MGAT and DGAT enzymes that differ in catalytic properties, subcellular localization, tissue distribution, and physiological functions. MGAT and DGAT enzymes play fundamental roles in the metabolism of monoacylglycerol (MAG), diacylglycerol (DAG), and triacylglycerol (TAG) that are involved in many aspects of physiological functions, such as intestinal fat absorption, lipoprotein assembly, adipose tissue formation, signal transduction, satiety, and lactation. The recent progress in the phenotypic characterization of mice deficient in MGAT and DGAT enzymes and the development of chemical inhibitors have revealed important roles of these enzymes in the regulation of energy homeostasis and insulin sensitivity. Consequently, selective inhibition of MGAT or DGAT enzymes by synthetic compounds may provide novel treatment for obesity and its related metabolic complications.

Multigene families encode the major enzymes of antioxidant metabolism in Eucalyptus grandis L

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Felipe Karam Teixeira

2005-01-01

Full Text Available Antioxidant metabolism protects cells from oxidative damage caused by reactive oxygen species (ROS. In plants, several enzymes act jointly to maintain redox homeostasis. Moreover, isoform diversity contributes to the fine tuning necessary for plant responses to both exogenous and endogenous signals influencing antioxidant metabolism. This study aimed to provide a comprehensive view of the major classes of antioxidant enzymes in the woody species Eucalyptus grandis. A careful survey of the FORESTs data bank revealed 36 clusters as encoding antioxidant enzymes: six clusters encoding ascorbate peroxidase (APx isozymes, three catalase (CAT proteins, three dehydroascorbate reductase (DHAR, two glutathione reductase (GR isozymes, four monodehydroascorbate reductase (MDHAR, six phospholipid hydroperoxide glutathione peroxidases (PhGPx, and 12 encoding superoxide dismutases (SOD isozymes. Phylogenetic analysis demonstrated that all clusters (identified herein grouped with previously characterized antioxidant enzymes, corroborating the analysis performed. With respect to enzymes involved in the ascorbate-glutathione cycle, both cytosolic and chloroplastic isoforms were putatively identified. These sequences were widely distributed among the different ESTs libraries indicating a broad gene expression pattern. Overall, the data indicate the importance of antioxidant metabolism in eucalyptus.

Major components of metabolic syndrome and nutritional intakes in different genotype of UCP2 -866G/A gene polymorphisms in patients with NAFLD.

Science.gov (United States)

Abbasalizad Farhangi, Mahdieh; Mohseni, Fatemeh; Farajnia, Safar; Jafarabadi, Mohammad-Asghari

2016-06-14

It has been suggested that dietary modifications in combination with genetic predisposition play an important role in the pathogenesis of NAFLD. In the current study we aimed to investigate the major components of metabolic syndrome in patients with non-alcoholic fatty liver disease (NAFLD) and nutritional intakes according to different genotype of uncoupling protein-2 (UCP2) -866G/A gene polymorphism in these patients. In this study 151 participants including 75 patients with NAFLD and 76 healthy individuals were enrolled. Dietary intakes were assessed using a semi-quantitative food-frequency questionnaire. Physical activity was obtained by metabolic equivalent questionnaire. Anthropometric assessments were conducted by a trained researcher and body mass index and waist to hip ratio were calculated. Body composition was measured by bioelectrical impedance analysis and biochemical assays including fasting serum glucose, liver enzymes and lipid profiles were measured. Polymorphisms of -866G/A UCP2 gene was determined using polymerase chain reaction-restriction fragment length polymorphism method. Serum triglyceride concentrations in 53.3 % of NAFLD patients compared with 35.5 % of control group was more than 150 mg/dl (P = 0.034). A significantly higher prevalence of low serum high density lipoprotein cholesterol concentrations was also observed in female NAFLD patients (P  0.05). However, according to genotypes patients with AG genotype had significantly higher protein consumption compared with control group (P < 0.05). Significantly higher consumption of dietary iron and copper in NAFLD patients with AG genotype was only observed among patients with NAFLD. However, the comparison of macro and micronutrient intakes in control group sound for stronger differences for AA genotype although these differences did not achieve significant threshold. A high prevalence of metabolic abnormalities was reported among NAFLD patients. Additionally, among NAFLD group

Diet-gene interactions between dietary fat intake and common polymorphisms in determining lipid metabolism

Energy Technology Data Exchange (ETDEWEB)

Corella, D.

2009-07-01

Current dietary guidelines for fat intake have not taken into consideration the possible genetic differences underlying the individual variability in responsiveness to dietary components. Genetic variability has been identified in humans for all the known lipid metabolism-related genes resulting in a plethora of candidate genes and genetic variants to examine in diet-gene interaction studies focused on fat consumption. Some examples of fat-gene interaction are reviewed. These include: the interaction between total intake and the 14C/T in the hepatic lipase gene promoter in determining high-density lipoprotein cholesterol (HDL-C) metabolism; the interaction between polyunsaturated fatty acids (PUFA) and the 5G/A polymorphism in the APOA1 gene plasma HDL-C concentrations; the interaction between PUFA and the L162V polymorphism in the PPARA gene in determining triglycerides and APOC3 concentrations; and the interaction between PUFA intake and the -1131T>C in the APOA5 gene in determining triglyceride metabolism. Although hundreds of diet-gene interaction studies in lipid metabolism have been published, the level of evidence to make specific nutritional recommendations to the population is still low and more research in nutrigenetics has to be undertaken. (Author) 31 refs.

Association between insertion/deletion polymorphism in angiotensin-converting enzyme gene and acute lung injury/acute respiratory distress syndrome: a meta-analysis

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Matsuda Akihisa

2012-08-01

Full Text Available Abstract Background A previous meta-analysis reported a positive association between an insertion/deletion (I/D polymorphism in the angiotensin-converting enzyme gene (ACE and the risk of acute lung injury (ALI/acute respiratory distress syndrome (ARDS. Here, we updated this meta-analysis and additionally assessed the association of this polymorphism with ALI/ARDS mortality. Methods We searched electronic databases through October 2011 for the terms “angiotensin-converting enzyme gene”, “acute lung injury”, and “acute respiratory distress syndrome,” and reviewed all studies that reported the relationship of the I/D polymorphism in ACE with ALI/ARDS in humans. Seven studies met the inclusion criteria, comprising 532 ALI/ARDS patients, 3032 healthy controls, and 1432 patients without ALI/ARDS. We used three genetic models: the allele, dominant, and recessive models. Results The ACE I/D polymorphism was not associated with susceptibility to ALI/ARDS for any genetic model. However, the ACE I/D polymorphism was associated with the mortality risk of ALI/ARDS in Asian subjects ( Pallele Pdominant = 0.001, Precessive = 0.002. This finding remained significant after correction for multiple comparisons. Conclusions There is a possible association between the ACE I/D polymorphism genotype and the mortality risk of ALI/ARDS in Asians.

Astrocyte-neuron crosstalk regulates the expression and subcellular localization of carbohydrate metabolism enzymes.

Science.gov (United States)

Mamczur, Piotr; Borsuk, Borys; Paszko, Jadwiga; Sas, Zuzanna; Mozrzymas, Jerzy; Wiśniewski, Jacek R; Gizak, Agnieszka; Rakus, Dariusz

2015-02-01

Astrocytes releasing glucose- and/or glycogen-derived lactate and glutamine play a crucial role in shaping neuronal function and plasticity. Little is known, however, how metabolic functions of astrocytes, e.g., their ability to degrade glucosyl units, are affected by the presence of neurons. To address this issue we carried out experiments which demonstrated that co-culturing of rat hippocampal astrocytes with neurons significantly elevates the level of mRNA and protein for crucial enzymes of glycolysis (phosphofructokinase, aldolase, and pyruvate kinase), glycogen metabolism (glycogen synthase and glycogen phosphorylase), and glutamine synthetase in astrocytes. Simultaneously, the decrease of the capability of neurons to metabolize glucose and glutamine is observed. We provide evidence that neurons alter the expression of astrocytic enzymes by secretion of as yet unknown molecule(s) into the extracellular fluid. Moreover, our data demonstrate that almost all studied enzymes may localize in astrocytic nuclei and this localization is affected by the co-culturing with neurons which also reduces proliferative activity of astrocytes. Our results provide the first experimental evidence that the astrocyte-neuron crosstalk substantially affects the expression of basal metabolic enzymes in the both types of cells and influences their subcellular localization in astrocytes. © 2014 Wiley Periodicals, Inc.

Gene therapy for the circumvention of inborn errors of metabolism (IEM) caused by single-nucleotide-polymorphisms (SNPs).

Science.gov (United States)

Wiseman, Alan

2004-01-01

Single nucleotide polymorphisms (SNPs) are the result of point mutations in nuclear (and mitochondrial) DNA. Such localised damage to DNA (and its replicative mechanisms) may not be excised fully by the DNA repair mechanism in the genome: and therefore can become inheritable; subsequently to manifest later as an inborn error of metabolism (IEM). Causes of mutagenic damage to the DNA can include background radiation (such as emitted by radon gas), and by reactive oxygen species (ROS): and also by mutagenic chemicals that occur naturally (inter alia in the diet). Other causes of DNA damage are variable environmental hazards such as solar-derived short wave ultraviolet light A. Gene therapy involves the placement of missing genes into particular tissues by the harnessing of suitable vectors (originally these were animal viruses such as SV40). For example, gene therapy in the rat for diabetes has succeeded by liver-production of insulin (using genes obtained from pancreatic Islets of Langerhans cells). Many inborn errors of metabolism could be treated in this way: examples may include 100 haemoglobinopathies (such as sickle cell anaemia), phenylketonuria; and other diseases caused by lack of tissue-production of a particular enzyme (in its catalytically-active conformation).

Association between angiotensin II receptor gene polymorphism and serum angiotensin converting enzyme (SACE) activity in patients with sarcoidosis

OpenAIRE

Takemoto, Y.; Sakatani, M.; Takami, S.; Tachibana, T.; Higaki, J.; Ogihara, T.; Miki, T.; Katsuya, T.; Tsuchiyama, T.; Yoshida, A.; Yu, H.; Tanio, Y.; Ueda, E.

1998-01-01

BACKGROUND—Serum angiotensin converting enzyme (SACE) is considered to reflect disease activity in sarcoidosis. SACE activity is increased in many patients with active sarcoid lesions. The mechanism for the increased SACE activity in this disease has not been clarified. ACE insertion/deletion (I/D) gene polymorphism has been reported to have an association with SACE levels in sarcoidosis, but no evidence of an association between angiotensin II receptor gene polymorphism and SA...

Spatial localization of the first and last enzymes effectively connects active metabolic pathways in bacteria.

Science.gov (United States)

Meyer, Pablo; Cecchi, Guillermo; Stolovitzky, Gustavo

2014-12-14

Although much is understood about the enzymatic cascades that underlie cellular biosynthesis, comparatively little is known about the rules that determine their cellular organization. We performed a detailed analysis of the localization of E.coli GFP-tagged enzymes for cells growing exponentially. We found that out of 857 globular enzymes, at least 219 have a discrete punctuate localization in the cytoplasm and catalyze the first or the last reaction in 60% of biosynthetic pathways. A graph-theoretic analysis of E.coli's metabolic network shows that localized enzymes, in contrast to non-localized ones, form a tree-like hierarchical structure, have a higher within-group connectivity, and are traversed by a higher number of feed-forward and feedback loops than their non-localized counterparts. A Gene Ontology analysis of these enzymes reveals an enrichment of terms related to essential metabolic functions in growing cells. Given that these findings suggest a distinct metabolic role for localization, we studied the dynamics of cellular localization of the cell wall synthesizing enzymes in B. subtilis and found that enzymes localize during exponential growth but not during stationary growth. We conclude that active biochemical pathways inside the cytoplasm are organized spatially following a rule where their first or their last enzymes localize to effectively connect the different active pathways and thus could reflect the activity state of the cell's metabolic network.

Effect of BCHE single nucleotide polymorphisms on lipid metabolism markers in women

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Jéssica de Oliveira

2017-05-01

Full Text Available Abstract Butyrylcholinesterase (BChE activity and polymorphisms in its encoding gene had previously been associated with metabolic traits of obesity. This study investigated the association of three single nucleotide polymorphisms (SNPs in the BCHE gene: -116G > A (rs1126680, 1615GA (rs1803274, 1914A 0.05. The dominant and recessive models were tested, and different effects were found. The -116A allele showed a dominant effect in BChE activity reduction in both non-obese and obese women (p = 0.045 and p G and 1615GA SNPs influenced the TG levels only in obese women. The 1914G and the 1615A alleles were associated with decreased plasma levels of TG. Thus, our results suggest that the obesity condition, characterized by loss of energy homeostasis, is modulated by BCHE polymorphisms.

Renin-angiotensin system inhibitors, angiotensin I-converting enzyme gene insertion/deletion polymorphism, and cancer: The Rotterdam study

NARCIS (Netherlands)

R. van der Knaap (Ronald); C. Siemes (Claire); J.W.W. Coebergh (Jan Willem); P. Tikka-Kleemola (Päivi); A. Hofman (Albert); B.H.Ch. Stricker (Bruno)

2008-01-01

textabstractBACKGROUND. Angiotensin I-converting enzyme (ACE) inhibitors, angiotensin II antagonists, and the ACE insertion/deletion (I/D) gene polymorphism all influence serum angiotensin II action. Because angiotensin II levels have been associated with cancer, the objective of the current

EnzDP: improved enzyme annotation for metabolic network reconstruction based on domain composition profiles.

Science.gov (United States)

Nguyen, Nam-Ninh; Srihari, Sriganesh; Leong, Hon Wai; Chong, Ket-Fah

2015-10-01

Determining the entire complement of enzymes and their enzymatic functions is a fundamental step for reconstructing the metabolic network of cells. High quality enzyme annotation helps in enhancing metabolic networks reconstructed from the genome, especially by reducing gaps and increasing the enzyme coverage. Currently, structure-based and network-based approaches can only cover a limited number of enzyme families, and the accuracy of homology-based approaches can be further improved. Bottom-up homology-based approach improves the coverage by rebuilding Hidden Markov Model (HMM) profiles for all known enzymes. However, its clustering procedure relies firmly on BLAST similarity score, ignoring protein domains/patterns, and is sensitive to changes in cut-off thresholds. Here, we use functional domain architecture to score the association between domain families and enzyme families (Domain-Enzyme Association Scoring, DEAS). The DEAS score is used to calculate the similarity between proteins, which is then used in clustering procedure, instead of using sequence similarity score. We improve the enzyme annotation protocol using a stringent classification procedure, and by choosing optimal threshold settings and checking for active sites. Our analysis shows that our stringent protocol EnzDP can cover up to 90% of enzyme families available in Swiss-Prot. It achieves a high accuracy of 94.5% based on five-fold cross-validation. EnzDP outperforms existing methods across several testing scenarios. Thus, EnzDP serves as a reliable automated tool for enzyme annotation and metabolic network reconstruction. Available at: www.comp.nus.edu.sg/~nguyennn/EnzDP .

Abnormal islet sphingolipid metabolism in type 1 diabetes

DEFF Research Database (Denmark)

Holm, Laurits J; Krogvold, Lars; Hasselby, Jane P

2018-01-01

AIMS/HYPOTHESIS: Sphingolipids play important roles in beta cell physiology, by regulating proinsulin folding and insulin secretion and in controlling apoptosis, as studied in animal models and cell cultures. Here we investigate whether sphingolipid metabolism may contribute to the pathogenesis....... Transcriptional analysis was used to evaluate expression of sphingolipid-related genes in isolated human islets. Genome-wide association studies (GWAS) and a T cell proliferation assay were used to identify type 1 diabetes related polymorphisms and test how these affect cellular islet autoimmunity. Finally, we...... diabetes, which were associated with reduced expression of enzymes involved in sphingolipid metabolism. Next, we discovered eight gene polymorphisms (ORMDL3, SPHK2, B4GALNT1, SLC1A5, GALC, PPARD, PPARG and B4GALT1) involved in sphingolipid metabolism that contribute to the genetic predisposition to type 1...

Serum paraoxonase-1 gene polymorphism and enzyme activity in patients with urolithiasis.

Science.gov (United States)

Atar, Arda; Gedikbasi, Asuman; Sonmezay, Erkan; Kiraz, Zeynep Kusku; Abbasoglu, Semra; Tasci, Ali Ihsan; Tugcu, Volkan

2016-01-01

Paraoxonase-1 (PON1) is a high-density lipoprotein-associated enzyme implicated in the pathogenesis of atherosclerosis by protecting lipoproteins against peroxidation. PON1 has two genetic polymorphisms both due to amino acid substitution, one involving glutamine and arginine at position 192 and the other leucine and methionine at position 55. Recent reports suggest that nephrolithiasis and atherosclerosis share a number of risk factors. Our study aimed to compare the effects of PON1 192, PON1 55 polymorphisms, and PON1 activity in patients with urolithiasis and controls. PON1's arylesterase/paraoxonase activities and phenotype were determined in 158 stone forming cases (Group 1) and 138 non-stone forming controls (Group 2). The PON1 192 and PON1 55 polymorphisms were studied by polymerase chain reaction/restriction fragment length polymorphism. Paraoxonase activity was significantly lower in Group 1 than Group 2 (112 ± 31.8 vs. 208 ± 53.1 IU/L) (p < 0.001). The PON1 L55M polymorphism was significantly higher in Group 1. The "M" allele coding for PON1 was higher in Group 1 (p < 0.001). PON1 192 RR homozygotes had significantly higher PON1 activity than QR and QQ genotypes among all the patients (p < 0.001). The results of our study demonstrate that the PON1 55 gene "M" allele is associated with renal stone disease. Individuals possessing the "M" allele have a higher incidence of urolithiasis. The results of this study provide genetic evidence that the PON1 gene may play a role in stone formation. PON1 genotype determination may provide a tool to identify individuals who are at risk of urolithiasis.

A catalogue of polymorphisms related to xenobiotic metabolism and cancer susceptibility.

Science.gov (United States)

Gemignani, Federica; Landi, Stefano; Vivant, Franck; Zienolddiny, Shanbeh; Brennan, Paul; Canzian, Federico

2002-08-01

High-throughput genotyping technology of multiple genes based on large samples of cases and controls are likely to be important in identifying common genes which have a moderate effect on the development of specific diseases. We present here a comprehensive list of 313 known experimentally confirmed polymorphisms in 54 genes which are particularly relevant for metabolism of drugs, alcohol, tobacco, and other potential carcinogens. We have compiled a catalog with a standardized format that summarizes the genetic and biochemical properties of the selected polymorphisms. We have also confirmed or redesigned experimental conditions for simplex or multiplex PCR amplification of a subset of 168 SNPs of particular interest, which will provide the basis for the design of assays compatible with high-throughput genotyping.

Relationships between FTO rs9939609, MC4R rs17782313, and PPARγ rs1801282 polymorphisms and the occurrence of selected metabolic and hormonal disorders in middle-aged and elderly men – a preliminary study

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Rotter I

2016-11-01

Full Text Available Iwona Rotter,1 Karolina Skonieczna-Żydecka,2 Danuta Kosik-Bogacka,3 Grażyna Adler,2 Aleksandra Rył,4 Maria Laszczyńska4 1Department of Medical Rehabilitation, 2Department of Gerontobiology, 3Department of Biology and Medical Parasitology, 4Department of Histology and Developmental Biology, Pomeranian Medical University, Szczecin, Poland Purpose: Metabolic disorders, including MetS, obesity, and lipid disorders, may be related to genetic factors. Metabolic disorders are associated with decreased TS levels in aging men. The aim of this study was to evaluate the relationship between FTO rs9939609, MC4R rs17782313, and PPARɣ rs1801282 polymorphisms and the presence of MetS and its components, the concurrent lipid disorders, as well as sex hormone concentrations. Subjects and methods: This study involved 272 men of Caucasian descent aged 50–75 years. Lipid profile, including TCh, LDL, HDL, and TG, was evaluated by spectrophotometric method. Anthropometric measurements concerned WC and blood pressure. MetS was diagnosed according to the criteria of the IDF. Sex hormone profile, including TST, FTS, E2, DHEAS, and SHBG, was examined using enzyme-linked immunosorbent assay. Polymorphisms within FTO, MC4R, and PPARɣ genes were identified using polymerase chain reaction-restriction fragments length polymorphism. Results: This study did not show links between the analyzed genetic polymorphisms and the presence of MetS, T2DM, HT, and obesity. However, higher concentrations of TCh and LDL were found in men with the FTO rs9939609 polymorphism in the recessive mode of inheritance (P=0.03 and P=0.05, respectively. Lower WC was found to be associated with MC4R rs17782313 gene inherited in the same model (P=0.005. Conclusion: FTO rs9939609, MC4R rs17782313, and PPARɣ rs1801282 polymorphisms seem to have little effect on the incidence of metabolic malfunctions and no effect on androgen-related disorders in the examined middle-aged and elderly men

SLC2A9 and ZNF518B polymorphisms correlate with gout-related metabolic indices in Chinese Tibetan populations.

Science.gov (United States)

Zhang, X Y; Geng, T T; Liu, L J; Yuan, D Y; Feng, T; Kang, L L; Jin, T B; Chen, C

2015-08-19

Current evidence suggests that heredity and metabolic syndrome contribute to gout progression. SLC2A9 and ZNF518B may play a role in gout progression in different populations, but no studies have focused on the Tibetan Chinese population. In this study, we determined whether variations in these 2 genes were correlated with gout-related indices in Chinese-Tibetan gout patients. We detected 6 single nucleotide polymorphisms in SLC2A9 and ZNF518B in 319 Chinese Tibetan gout patients. One-way analysis of variance was used to evaluate the polymorphisms' effects on gout based on mean serum levels of metabolism indicators. Polymorphisms in SLC2A9 and ZNF518B affected multiple risk factors related to gout development. Significant differences in serum triglyceride levels and high-density lipoprotein-cholesterol level were detected between different genotypic groups with SLC2A9 polymorphisms rs13129697 (P = 0.022), rs4447863 (P = 0.018), and rs1014290 (P = 0.045). Similarly in ZNF518B, rs3217 (P = 0.016) and rs10016022 (P = 0.046) were associated with high creatinine and glucose levels, respectively. This study is the first to investigate and identify positive correlations between SLC2A9 and ZNF518B gene polymorphisms and metabolic indices in Tibetan gout patients. We found significant evidence indicating that genetic polymorphisms affect gout-related factors in Chinese Tibetan populations.

Human Metabolic Enzymes Deficiency: A Genetic Mutation Based Approach

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Swati Chaturvedi

2016-01-01

Full Text Available One of the extreme challenges in biology is to ameliorate the understanding of the mechanisms which emphasize metabolic enzyme deficiency (MED and how these pretend to have influence on human health. However, it has been manifested that MED could be either inherited as inborn error of metabolism (IEM or acquired, which carries a high risk of interrupted biochemical reactions. Enzyme deficiency results in accumulation of toxic compounds that may disrupt normal organ functions and cause failure in producing crucial biological compounds and other intermediates. The MED related disorders cover widespread clinical presentations and can involve almost any organ system. To sum up the causal factors of almost all the MED-associated disorders, we decided to embark on a less traveled but nonetheless relevant direction, by focusing our attention on associated gene family products, regulation of their expression, genetic mutation, and mutation types. In addition, the review also outlines the clinical presentations as well as diagnostic and therapeutic approaches.

Dissecting the genetic and metabolic mechanisms of adaptation to the knockout of a major metabolic enzyme in Escherichia coli

DEFF Research Database (Denmark)

Long, Christopher P.; Gonzalez, Jacqueline E.; Feist, Adam M.

2018-01-01

Unraveling the mechanisms of microbial adaptive evolution following genetic or environmental challenges is of fundamental interest in biological science and engineering. When the challenge is the loss of a metabolic enzyme, adaptive responses can also shed significant insight into metabolic...

CYP polymorphisms and pathological conditions related to chronic exposure to organochlorine pesticides

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Anca Oana Docea

Full Text Available The association between genetic variations in the cytochrome P450 (CYP family genes and pathological conditions related to long-term exposure to organochlorine compounds (OCs deserves further elucidation. OCs are persistent organic pollutants with bioaccumulative and lipophilic characteristics. They can act as endocrine disruptors and perturb cellular mechanisms. Prolonged exposure to OCs has been associated with different pathological manifestations. CYP genes are responsible for transcribing enzymes essential in xenobiotic metabolism. Therefore, polymorphisms in these genetic sequences a. alter the metabolic pathways, b. induce false cellular responses, and c. may provoke pathological conditions. The main aim of this review is to define the interaction between parameters a, b and c at a mechanistic/molecular level, with references in clinical cases. Keywords: Organochlorine compounds, Cytochrome P450, Genetic polymorphisms, Pathogenesis, Environmental pollutants

Heme-containing enzymes and inhibitors for tryptophan metabolism.

Science.gov (United States)

Yan, Daojing; Lin, Ying-Wu; Tan, Xiangshi

2017-09-20

Iron-containing enzymes such as heme enzymes play crucial roles in biological systems. Three distinct heme-containing dioxygenase enzymes, tryptophan 2,3-dioxygenase (TDO), indoleamine 2,3-dioxygenase 1 (IDO1) and indoleamine 2,3-dioxygenase 2 (IDO2) catalyze the initial and rate-limiting step of l-tryptophan catabolism through the kynurenine pathway in mammals. Overexpression of these enzymes causes depletion of tryptophan and the accumulation of metabolic products, which contributes to tumor immune tolerance and immune dysregulation in a variety of disease pathologies. In the past few decades, IDO1 has garnered the most attention as a therapeutic target with great potential in cancer immunotherapy. Many potential inhibitors of IDO1 have been designed, synthesized and evaluated, among which indoximod (d-1-MT), INCB024360, GDC-0919 (formerly NLG-919), and an IDO1 peptide-based vaccine have advanced to the clinical trial stage. However, recently, the roles of TDO and IDO2 have been elucidated in immune suppression. In this review, the current drug discovery landscape for targeting TDO, IDO1 and IDO2 is highlighted, with particular attention to the recent use of drugs in clinical trials. Moreover, the crystal structures of these enzymes, in complex with inhibitors, and the mechanisms of Trp catabolism in the first step, are summarized to provide information for facilitating the discovery of new enzyme inhibitors.

Deletion/insertion polymorphism of the angiotensin-converting enzyme gene and white matter hyperintensities in dementia: A pilot study.

NARCIS (Netherlands)

Purandare, N.; Oude Voshaar, R.C.; Davidson, Y.; Gibbons, L.; Hardicre, J.; Byrne, J.; McCollum, C.N.; Jackson, A.; Burns, A.; Mann, D.M.

2006-01-01

OBJECTIVES: To examine the association between the angiotensin-converting enzyme (ACE) deletion/insertion (D/I) polymorphism and white matter hyperintensities (WMHs) in patients with dementia. DESIGN: Observational pilot study with adjustment for potential confounders using analysis of covariance.

Metabolic enzyme expression highlights a key role for MTHFD2 and the mitochondrial folate pathway in cancer

Science.gov (United States)

Nilsson, Roland; Jain, Mohit; Madhusudhan, Nikhil; Sheppard, Nina Gustafsson; Strittmatter, Laura; Kampf, Caroline; Huang, Jenny; Asplund, Anna; Mootha, Vamsi K.

2014-01-01

Metabolic remodeling is now widely regarded as a hallmark of cancer, but it is not clear whether individual metabolic strategies are frequently exploited by many tumours. Here we compare messenger RNA profiles of 1,454 metabolic enzymes across 1,981 tumours spanning 19 cancer types to identify enzymes that are consistently differentially expressed. Our meta-analysis recovers established targets of some of the most widely used chemotherapeutics, including dihydrofolate reductase, thymidylate synthase and ribonucleotide reductase, while also spotlighting new enzymes, such as the mitochondrial proline biosynthetic enzyme PYCR1. The highest scoring pathway is mitochondrial one-carbon metabolism and is centred on MTHFD2. MTHFD2 RNA and protein are markedly elevated in many cancers and correlated with poor survival in breast cancer. MTHFD2 is expressed in the developing embryo, but is absent in most healthy adult tissues, even those that are proliferating. Our study highlights the importance of mitochondrial compartmentalization of one-carbon metabolism in cancer and raises important therapeutic hypotheses.

Potential Links between Impaired One-Carbon Metabolism Due to Polymorphisms, Inadequate B-Vitamin Status, and the Development of Alzheimer’s Disease

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Barbara Troesch

2016-12-01

Full Text Available Alzheimer’s disease (AD is the major cause of dementia and no preventive or effective treatment has been established to date. The etiology of AD is poorly understood, but genetic and environmental factors seem to play a role in its onset and progression. In particular, factors affecting the one-carbon metabolism (OCM are thought to be important and elevated homocysteine (Hcy levels, indicating impaired OCM, have been associated with AD. We aimed at evaluating the role of polymorphisms of key OCM enzymes in the etiology of AD, particularly when intakes of relevant B-vitamins are inadequate. Our review indicates that a range of compensatory mechanisms exist to maintain a metabolic balance. However, these become overwhelmed if the activity of more than one enzyme is reduced due to genetic factors or insufficient folate, riboflavin, vitamin B6 and/or vitamin B12 levels. Consequences include increased Hcy levels and reduced capacity to synthetize, methylate and repair DNA, and/or modulated neurotransmission. This seems to favor the development of hallmarks of AD particularly when combined with increased oxidative stress e.g., in apolipoprotein E (ApoE ε4 carriers. However, as these effects can be compensated at least partially by adequate intakes of B-vitamins, achieving optimal B-vitamin status for the general population should be a public health priority.

Transgenic Mouse Models for Alcohol Metabolism, Toxicity and Cancer

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Heit, Claire; Dong, Hongbin; Chen, Ying; Shah, Yatrik M.; Thompson, David C.; Vasiliou, Vasilis

2015-01-01

Alcohol abuse leads to tissue damage including a variety of cancers; however, the molecular mechanisms by which this damage occurs remains to be fully understood. The primary enzymes involved in ethanol metabolism include alcohol dehydrogenase (ADH), cytochrome P450 isoform 2E1, (CYP2E1), catalase (CAT), and aldehyde dehydrogenases (ALDH). Genetic polymorphisms in human genes encoding these enzymes are associated with increased risks of alcohol-related tissue damage, as well as differences in...

Metabolism and transport of tamoxifen in relation to its effectiveness

DEFF Research Database (Denmark)

Cronin-Fenton, Deirdre P; Damkier, Per; Lash, Timothy L

2014-01-01

Tamoxifen reduces the rate of breast cancer recurrence by approximately a half. Tamoxifen is metabolized to more active metabolites by enzymes encoded by polymorphic genes, including cytochrome P450 2D6 (CYP2D6). Tamoxifen is a substrate for ATP-binding cassette transporter proteins. We review ta...

The relative importance of kinetic mechanisms and variable enzyme abundances for the regulation of hepatic glucose metabolism--insights from mathematical modeling.

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Bulik, Sascha; Holzhütter, Hermann-Georg; Berndt, Nikolaus

2016-03-02

Adaptation of the cellular metabolism to varying external conditions is brought about by regulated changes in the activity of enzymes and transporters. Hormone-dependent reversible enzyme phosphorylation and concentration changes of reactants and allosteric effectors are the major types of rapid kinetic enzyme regulation, whereas on longer time scales changes in protein abundance may also become operative. Here, we used a comprehensive mathematical model of the hepatic glucose metabolism of rat hepatocytes to decipher the relative importance of different regulatory modes and their mutual interdependencies in the hepatic control of plasma glucose homeostasis. Model simulations reveal significant differences in the capability of liver metabolism to counteract variations of plasma glucose in different physiological settings (starvation, ad libitum nutrient supply, diabetes). Changes in enzyme abundances adjust the metabolic output to the anticipated physiological demand but may turn into a regulatory disadvantage if sudden unexpected changes of the external conditions occur. Allosteric and hormonal control of enzyme activities allow the liver to assume a broad range of metabolic states and may even fully reverse flux changes resulting from changes of enzyme abundances alone. Metabolic control analysis reveals that control of the hepatic glucose metabolism is mainly exerted by enzymes alone, which are differently controlled by alterations in enzyme abundance, reversible phosphorylation, and allosteric effects. In hepatic glucose metabolism, regulation of enzyme activities by changes of reactants, allosteric effects, and reversible phosphorylation is equally important as changes in protein abundance of key regulatory enzymes.

Expression of Enzymes that Metabolize Medications

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Wotring, V. E.; Peters, C. P.

2011-01-01

INTRODUCTION: Increased exposure to radiation is one physiological stressor associated with spaceflight and it is feasible to conduct ground experiments using known radiation exposures. The health of the liver, especially the activity rate of its metabolic enzymes, determines the concentration of circulating drugs as well as the duration of their efficacy. While radiation is known to alter normal physiological function, how radiation affects liver metabolism of administered medications is unclear. Crew health could be affected if the actions of medications used in spaceflight deviated from expectations formed during terrestrial medication use. This study is an effort to identify liver metabolic enzymes whose expression is altered by spaceflight or by radiation exposures that mimic features of the spaceflight environment. METHODS: Using procedures approved by the Animal Care and Use Committee, mice were exposed to either 137Cs (controls, 50 mGy, 6Gy, or 50 mGy + 6Gy separated by 24 hours) or 13 days of spaceflight on STS 135. Animals were anesthetized and sacrificed at several time points (4 hours, 24 hours or 7 days) after their last radiation exposure, or within 6 hours of return to Earth for the STS 135 animals. Livers were removed immediately and flash-frozen in liquid nitrogen. Tissue was homogenized, RNA extracted, purified and quality-tested. Complementary DNA was prepared from high-quality RNA samples, and used in RT-qPCR experiments to determine relative expression of a wide variety of genes involved in general metabolism and drug metabolism. RESULTS: Results of the ground radiation exposure experiments indicated 65 genes of the 190 tested were significantly affected by at least one of the radiation doses. Many of the affected genes are involved in the metabolism of drugs with hydrophobic or steroid-like structures, maintenance of redox homeostasis and repair of DNA damage. Most affected genes returned to near control expression levels by 7 days post

Enzymes of energy metabolism in hatchlings of amazonian freshwater turtles (Testudines, Podocnemididae

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WP. Duncan

Full Text Available The metabolic profiles of selected tissues were analyzed in hatchlings of the Amazonian freshwater turtles Podocnemis expansa, P. unifilis and P. sextuberculata. Metabolic design in these species was judged based on the key enzymes of energy metabolism, with special emphasis on carbohydrate, lipid, amino acid and ketone body metabolism. All species showed a high glycolytic potential in all sampled tissues. Based on low levels of hexokinase, glycogen may be an important fuel for these species. The high lactate dehydrogenase activity in the liver may play a significant role in carbohydrate catabolism, possibly during diving. Oxidative metabolism in P. sextuberculata appears to be designed for the use of lipids, amino acids and ketone bodies. The maximal activities of 3-hydroxyacyl-CoA dehydrogenase, malate dehydrogenase, glutamine dehydrogenase, alanine aminotransferase and succinyl-CoA keto transferase display high aerobic potential, especially in muscle and liver tissues of this species. Although amino acids and ketone bodies may be important fuels for oxidative metabolism, carbohydrates and lipids are the major fuels used by P. expansa and P. unifilis. Our results are consistent with the food habits and lifestyle of Amazonian freshwater turtles. The metabolic design, based on enzyme activities, suggests that hatchlings of P. unifilis and P. expansa are predominately herbivorous, whereas P. sextuberculata rely on a mixed diet of animal matter and vegetation.

Influence of Cremophor EL and genetic polymorphisms on the pharmacokinetics of paclitaxel and its metabolites using a mechanism-based model.

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Fransson, Martin N; Gréen, Henrik; Litton, Jan-Eric; Friberg, Lena E

2011-02-01

The formulation vehicle Cremophor EL has previously been shown to affect paclitaxel kinetics, but it is not known whether it also affects the kinetics of paclitaxel metabolites. This information may be important for understanding paclitaxel metabolism in vivo and in the investigation of the role of genetic polymorphisms in the metabolizing enzymes CYP2C8 and CYP3A4/CYP3A5 and the ABCB1 transporter. In this study we used the population pharmacokinetic approach to explore the influence of predicted Cremophor EL concentrations on paclitaxel (Taxol) metabolites. In addition, correlations between genetic polymorphisms and enzyme activity with clearance of paclitaxel, its two primary metabolites, 6α-hydroxypaclitaxel and p-3'-hydroxypaclitaxel, and its secondary metabolite, 6α-p-3'-dihydroxypaclitaxel were investigated. Model building was based on 1156 samples from a study with 33 women undergoing paclitaxel treatment for gynecological cancer. Total concentrations of paclitaxel were fitted to a model described previously. One-compartment models characterized unbound metabolite concentrations. Total concentrations of 6α-hydroxypaclitaxel and p-3'-hydroxypaclitaxel were strongly dependent on predicted Cremophor EL concentrations, but this association was not found for 6α-p-3'-dihydroxypaclitaxel. Clearance of 6α-hydroxypaclitaxel (fraction metabolized) was significantly correlated (p < 0.05) to the ABCB1 allele G2677T/A. Individuals carrying the polymorphisms G/A (n = 3) or G/G (n = 5) showed a 30% increase, whereas individuals with polymorphism T/T (n = 8) showed a 27% decrease relative to those with the polymorphism G/T (n = 17). The correlation of G2677T/A with 6α-hydroxypaclitaxel has not been described previously but supports other findings of the ABCB1 transporter playing a part in paclitaxel metabolism.

In vivo enzyme activity in inborn errors of metabolism

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Thompson, G.N.; Walter, J.H.; Leonard, J.V.; Halliday, D. (Clinical Research Centre, Harrow (England))

1990-08-01

Low-dose continuous infusions of (2H5)phenylalanine, (1-13C)propionate, and (1-13C)leucine were used to quantitate phenylalanine hydroxylation in phenylketonuria (PKU, four subjects), propionate oxidation in methylmalonic acidaemia (MMA, four subjects), and propionic acidaemia (PA, four subjects) and leucine oxidation in maple syrup urine disease (MSUD, four subjects). In vivo enzyme activity in PKU, MMA, and PA subjects was similar to or in excess of that in adult controls (range of phenylalanine hydroxylation in PKU, 3.7 to 6.5 mumol/kg/h, control 3.2 to 7.9, n = 7; propionate oxidation in MMA, 15.2 to 64.8 mumol/kg/h, and in PA, 11.1 to 36.0, control 5.1 to 19.0, n = 5). By contrast, in vivo leucine oxidation was undetectable in three of the four MSUD subjects (less than 0.5 mumol/kg/h) and negligible in the remaining subject (2 mumol/kg/h, control 10.4 to 15.7, n = 6). These results suggest that significant substrate removal can be achieved in some inborn metabolic errors either through stimulation of residual enzyme activity in defective enzyme systems or by activation of alternate metabolic pathways. Both possibilities almost certainly depend on gross elevation of substrate concentrations. By contrast, only minimal in vivo oxidation of leucine appears possible in MSUD.

In vivo enzyme activity in inborn errors of metabolism

International Nuclear Information System (INIS)

Thompson, G.N.; Walter, J.H.; Leonard, J.V.; Halliday, D.

1990-01-01

Low-dose continuous infusions of [2H5]phenylalanine, [1-13C]propionate, and [1-13C]leucine were used to quantitate phenylalanine hydroxylation in phenylketonuria (PKU, four subjects), propionate oxidation in methylmalonic acidaemia (MMA, four subjects), and propionic acidaemia (PA, four subjects) and leucine oxidation in maple syrup urine disease (MSUD, four subjects). In vivo enzyme activity in PKU, MMA, and PA subjects was similar to or in excess of that in adult controls (range of phenylalanine hydroxylation in PKU, 3.7 to 6.5 mumol/kg/h, control 3.2 to 7.9, n = 7; propionate oxidation in MMA, 15.2 to 64.8 mumol/kg/h, and in PA, 11.1 to 36.0, control 5.1 to 19.0, n = 5). By contrast, in vivo leucine oxidation was undetectable in three of the four MSUD subjects (less than 0.5 mumol/kg/h) and negligible in the remaining subject (2 mumol/kg/h, control 10.4 to 15.7, n = 6). These results suggest that significant substrate removal can be achieved in some inborn metabolic errors either through stimulation of residual enzyme activity in defective enzyme systems or by activation of alternate metabolic pathways. Both possibilities almost certainly depend on gross elevation of substrate concentrations. By contrast, only minimal in vivo oxidation of leucine appears possible in MSUD

Angiotensin-converting enzyme insertion/deletion polymorphism association with obesity and some related disorders in Egyptian females: a case-control observational study.

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Motawi, Tarek K; Shaker, Olfat G; Shahin, Nancy N; Ahmed, Nancy M

2016-01-01

According to the WHO report in 2015, obesity is the fifth leading cause of death worldwide, and the prevalence of Egyptian female obesity is 37.5 %. Since obesity is highly influenced by genetics, and adipose tissue renin-angiotensin system is over-activated in obesity, the effect of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on obesity and related disorders was studied in several populations, because of its effect on ACE activity. Our objective was to study the association of ACE I/D polymorphism with obesity and certain related disorders, namely hypertension, insulin resistance and metabolic syndrome, in Egyptian females. Eighty female volunteers were recruited, blood pressure and body measurements were recorded and a fasting blood sample was obtained for the quantitation of glucose, lipid profile, insulin, leptin and identification of ACE I/D polymorphs. Subjects were grouped based on hypertension and obesity states. Comparisons of continuous parameters were made with independent sample t -test between two groups. The frequencies of ACE genotypes and alleles, and the association between gene polymorphism and metabolic parameters were assessed using chi-square or Fisher's exact test. Genotype frequencies were in Hardy-Weinberg equilibrium for all groups. Genotype distribution did not differ significantly between controls and cases of all the studied disorders. Although DD carriers had apparently higher parameters of blood pressure, lipid profile and insulin resistance, only diastolic blood pressure was almost significant ( p  = 0.057). I-carriers were significantly less susceptible to hypertension than DD carriers having normal waist/hip ratio ( p  = 0.007, OR = 17.29, CI = 1.81-164.96) and normal conicity index ( p  = 0.024, OR = 7.00, CI = 1.36-35.93). In DD genotype carriers, a significant association was found between insulin resistance and high body mass index ( p  = 0.004, OR = 8.89, CI�

Oral cancer cells may rewire alternative metabolic pathways to survive from siRNA silencing of metabolic enzymes

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Zhang, Min; Chai, Yang D; Brumbaugh, Jeffrey; Liu, Xiaojun; Rabii, Ramin; Feng, Sizhe; Misuno, Kaori; Messadi, Diana; Hu, Shen

2014-01-01

Cancer cells may undergo metabolic adaptations that support their growth as well as drug resistance properties. The purpose of this study is to test if oral cancer cells can overcome the metabolic defects introduced by using small interfering RNA (siRNA) to knock down their expression of important metabolic enzymes. UM1 and UM2 oral cancer cells were transfected with siRNA to transketolase (TKT) or siRNA to adenylate kinase (AK2), and Western blotting was used to confirm the knockdown. Cellular uptake of glucose and glutamine and production of lactate were compared between the cancer cells with either TKT or AK2 knockdown and those transfected with control siRNA. Statistical analysis was performed with student T-test. Despite the defect in the pentose phosphate pathway caused by siRNA knockdown of TKT, the survived UM1 or UM2 cells utilized more glucose and glutamine and secreted a significantly higher amount of lactate than the cells transferred with control siRNA. We also demonstrated that siRNA knockdown of AK2 constrained the proliferation of UM1 and UM2 cells but similarly led to an increased uptake of glucose/glutamine and production of lactate by the UM1 or UM2 cells survived from siRNA silencing of AK2. Our results indicate that the metabolic defects introduced by siRNA silencing of metabolic enzymes TKT or AK2 may be compensated by alternative feedback metabolic mechanisms, suggesting that cancer cells may overcome single defective pathways through secondary metabolic network adaptations. The highly robust nature of oral cancer cell metabolism implies that a systematic medical approach targeting multiple metabolic pathways may be needed to accomplish the continued improvement of cancer treatment

Prolyl hydroxylase domain enzymes: important regulators of cancer metabolism

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Yang M

2014-08-01

Full Text Available Ming Yang,1 Huizhong Su,1 Tomoyoshi Soga,2 Kamil R Kranc,3 Patrick J Pollard1 1Cancer Biology and Metabolism Group, Institute of Genetics and Molecular Medicine, University of Edinburgh, Edinburgh, UK; 2Institute for Advanced Biosciences, Keio University, Mizukami, Tsuruoka, Yamagata, Japan; 3MRC Centre for Regenerative Medicine, University of Edinburgh, Edinburgh, UK Abstract: The hypoxia-inducible factor (HIF prolyl hydroxylase domain enzymes (PHDs regulate the stability of HIF protein by post-translational hydroxylation of two conserved prolyl residues in its α subunit in an oxygen-dependent manner. Trans-4-prolyl hydroxylation of HIFα under normal oxygen (O2 availability enables its association with the von Hippel-Lindau (VHL tumor suppressor pVHL E3 ligase complex, leading to the degradation of HIFα via the ubiquitin-proteasome pathway. Due to the obligatory requirement of molecular O2 as a co-substrate, the activity of PHDs is inhibited under hypoxic conditions, resulting in stabilized HIFα, which dimerizes with HIFβ and, together with transcriptional co-activators CBP/p300, activates the transcription of its target genes. As a key molecular regulator of adaptive response to hypoxia, HIF plays important roles in multiple cellular processes and its overexpression has been detected in various cancers. The HIF1α isoform in particular has a strong impact on cellular metabolism, most notably by promoting anaerobic, whilst inhibiting O2-dependent, metabolism of glucose. The PHD enzymes also seem to have HIF-independent functions and are subject to regulation by factors other than O2, such as by metabolic status, oxidative stress, and abnormal levels of endogenous metabolites (oncometabolites that have been observed in some types of cancers. In this review, we aim to summarize current understandings of the function and regulation of PHDs in cancer with an emphasis on their roles in metabolism. Keywords: prolyl hydroxylase domain (PHD

[Effect of FABP2 gene G54A polymorphism on lipid and glucose metabolism in simple obesity children].

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Xu, Yunpeng; Rao, Xiaojiao; Hao, Min; Hou, Lijuan; Zhu, Xiaobo; Chang, Xiaotong

2016-01-01

To explore the relationship between intestinal fatty acid binding protein (FABP2) gene G54A polymorphism and simple childhood obesity, the effect of mutant 54A FABP2 gene on serum lipids and glucose metabolism. The total of 83 subjects with overweight/obesity and 100 subjects with healthy/normal weight were involved in this study. The G54A FABP2 gene allele and genotype frequencies between control group and overweight/obesity group were detected using polymerase chain reaction (PCR) -restriction fragment length polymorphism (RFLP) technology, and DNA sequences were confirmed by DNA sequencing. The automatic biochemical analyzer was used to detect fasting blood glucose (FBG), triglyceride (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) levels. Plasma insulin (Ins) was detected by radiation immune method, free fatty acids (FFA) was tested by ELISA method, insulin resistance index ( HOMA-IR ) was also calculated. The correlation between FABP2 G54A polymorphism and the development of children' obesity was analyzed. The relation between FABP2 G54A polymorphism and abnormal blood lipid and insulin resistance was assessed. The results of study on FABP2 gene polymorphism revealed as followed. In overweight/obese groups, the frequencies of GG, GA, AA genotypes was 33.7%, 49.4% and 16.9%, respectively. In control group, the frequencies of GG, GA, AA genotypes was 51. 0% , 40. 0% and 9. 0% , respectively. The differences between two groups was statistically significant (Χ2 = 6.27, P 0.05). The FABP2 gene G54A polymorphism is related to simple children obesity and lipid metabolism abnormality. The allele encoding in FABP2 gene may be a potential factor contributing to promoting lipid metabolism abnormality of and insulin resistance.

Thiamin diphosphate-dependent enzymes: from enzymology to metabolic regulation, drug design and disease models.

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Bunik, Victoria I; Tylicki, Adam; Lukashev, Nikolay V

2013-12-01

Bringing a knowledge of enzymology into research in vivo and in situ is of great importance in understanding systems biology and metabolic regulation. The central metabolic significance of thiamin (vitamin B1 ) and its diphosphorylated derivative (thiamin diphosphate; ThDP), and the fundamental differences in the ThDP-dependent enzymes of metabolic networks in mammals versus plants, fungi and bacteria, or in health versus disease, suggest that these enzymes are promising targets for biotechnological and medical applications. Here, the in vivo action of known regulators of ThDP-dependent enzymes, such as synthetic structural analogs of the enzyme substrates and thiamin, is analyzed in light of the enzymological data accumulated during half a century of research. Mimicking the enzyme-specific catalytic intermediates, the phosphonate analogs of 2-oxo acids selectively inhibit particular ThDP-dependent enzymes. Because of their selectivity, use of these compounds in cellular and animal models of ThDP-dependent enzyme malfunctions improves the validity of the model and its predictive power when compared with the nonselective and enzymatically less characterized oxythiamin and pyrithiamin. In vitro studies of the interaction of thiamin analogs and their biological derivatives with potential in vivo targets are necessary to identify and attenuate the analog selectivity. For both the substrate and thiamin synthetic analogs, in vitro reactivities with potential targets are highly relevant in vivo. However, effective concentrations in vivo are often higher than in vitro studies would suggest. The significance of specific inihibition of the ThDP-dependent enzymes for the development of herbicides, antibiotics, anticancer and neuroprotective strategies is discussed. © 2013 FEBS.

Single feature polymorphism (SFP-based selective sweep identification and association mapping of growth-related metabolic traits in Arabidopsis thaliana

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Stitt Mark

2010-03-01

Full Text Available Abstract Background Natural accessions of Arabidopsis thaliana are characterized by a high level of phenotypic variation that can be used to investigate the extent and mode of selection on the primary metabolic traits. A collection of 54 A. thaliana natural accession-derived lines were subjected to deep genotyping through Single Feature Polymorphism (SFP detection via genomic DNA hybridization to Arabidopsis Tiling 1.0 Arrays for the detection of selective sweeps, and identification of associations between sweep regions and growth-related metabolic traits. Results A total of 1,072,557 high-quality SFPs were detected and indications for 3,943 deletions and 1,007 duplications were obtained. A significantly lower than expected SFP frequency was observed in protein-, rRNA-, and tRNA-coding regions and in non-repetitive intergenic regions, while pseudogenes, transposons, and non-coding RNA genes are enriched with SFPs. Gene families involved in plant defence or in signalling were identified as highly polymorphic, while several other families including transcription factors are depleted of SFPs. 198 significant associations between metabolic genes and 9 metabolic and growth-related phenotypic traits were detected with annotation hinting at the nature of the relationship. Five significant selective sweep regions were also detected of which one associated significantly with a metabolic trait. Conclusions We generated a high density polymorphism map for 54 A. thaliana accessions that highlights the variability of resistance genes across geographic ranges and used it to identify selective sweeps and associations between metabolic genes and metabolic phenotypes. Several associations show a clear biological relationship, while many remain requiring further investigation.

Angiotensin converting enzyme insertion/deletion polymorphism: association with ethnic origin.

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Barley, J; Blackwood, A; Carter, N D; Crews, D E; Cruickshank, J K; Jeffery, S; Ogunlesi, A O; Sagnella, G A

1994-08-01

To determine the distribution of the insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene in several ethnic groups: Caucasian Europeans, Black Nigerians, Samoan Polynesians and Yanomami Indians. The ratio of the frequencies of the II, ID and DD genotypes were 1:2:1 in the Europeans, but there was a tendency towards a higher frequency of the D allele in the Nigerians. In contrast, the Samoans and the Yanomami Indians displayed a much higher frequency of the I allele than of the D allele. The relationship between ACE genotype and disease in these latter groups is still not known, but the present results clearly suggest that ethnic origin should be carefully considered in the increasing number of studies on the association between I/D ACE genotype and disease aetiology.

Relationship of metabolic syndrome and its components with -844 G/A and HindIII C/G PAI-1 gene polymorphisms in Mexican children

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De la Cruz-Mosso Ulises

2012-03-01

Full Text Available Abstract Background Several association studies have shown that -844 G/A and HindIII C/G PAI-1 polymorphisms are related with increase of PAI-1 levels, obesity, insulin resistance, glucose intolerance, hypertension and dyslipidemia, which are components of metabolic syndrome. The aim of this study was to analyze the allele and genotype frequencies of these polymorphisms in PAI-1 gene and its association with metabolic syndrome and its components in a sample of Mexican mestizo children. Methods This study included 100 children with an age range between 6-11 years divided in two groups: a 48 children diagnosed with metabolic syndrome and b 52 children metabolically healthy without any clinical and biochemical alteration. Metabolic syndrome was defined as the presence of three or more of the following criteria: fasting glucose levels ≥ 100 mg/dL, triglycerides ≥ 150 mg/dL, HDL-cholesterol th percentile, systolic blood pressure (SBP and diastolic blood pressure (DBP ≥ 95th percentile and insulin resistance HOMA-IR ≥ 2.4. The -844 G/A and HindIII C/G PAI-1 polymorphisms were analyzed by PCR-RFLP. Results For the -844 G/A polymorphism, the G/A genotype (OR = 2.79; 95% CI, 1.11-7.08; p = 0.015 and the A allele (OR = 2.2; 95% CI, 1.10-4.43; p = 0.015 were associated with metabolic syndrome. The -844 G/A and A/A genotypes were associated with increase in plasma triglycerides levels (OR = 2.6; 95% CI, 1.16 to 6.04; p = 0.02, decrease in plasma HDL-cholesterol levels (OR = 2.4; 95% CI, 1.06 to 5.42; p = 0.03 and obesity (OR = 2.6; 95% CI, 1.17-5.92; p = 0.01. The C/G and G/G genotypes of the HindIII C/G polymorphism contributed to a significant increase in plasma total cholesterol levels (179 vs. 165 mg/dL; p = 0.02 in comparison with C/C genotype. Conclusions The -844 G/A PAI-1 polymorphism is related with the risk of developing metabolic syndrome, obesity and atherogenic dyslipidemia, and the HindIII C/G PAI-1 polymorphism was associated with the

Genetic variation in genes for the xenobiotic-metabolizing enzymes CYP1A1, EPHX1, GSTM1, GSTT1 and GSTP1 and susceptibility to colorectal cancer in Lynch syndrome

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Pande, Mala; Amos, Christopher I.; Osterwisch, Daniel R.; Chen, Jinyun; Lynch, Patrick M.; Broaddus, Russell; Frazier, Marsha L.

2011-01-01

Individuals with Lynch syndrome are predisposed to cancer due to an inherited DNA mismatch repair gene mutation. However, there is significant variability observed in disease expression, likely due to the influence of other environmental, lifestyle, or genetic factors. Polymorphisms in genes encoding xenobiotic-metabolizing enzymes may modify cancer risk by influencing the metabolism and clearance of potential carcinogens from the body. In this retrospective analysis, we examined key candidate gene polymorphisms in CYP1A1, EPHX1, GSTT1, GSTM1, and GSTP1 as modifiers of age at onset of colorectal cancer among 257 individuals with Lynch syndrome. We found that subjects heterozygous for CYP1A1 I462V (c.1384A>G) developed colorectal cancer 4 years earlier than those with the homozygous wild-type genotype (median ages 39 and 43 years, respectively; log-rank test P = 0.018). Furthermore, being heterozygous for the CYP1A1 polymorphisms, I462V and Msp1 (g.6235T>C), was associated with an increased risk for developing colorectal cancer [adjusted hazard ratio for AG relative to AA = 1.78, 95% CI = 1.16–2.74, P = 0.008; and hazard ratio for TC relative to TT = 1.53, 95% CI = 1.06–2.22, P = 0.02]. Since homozygous variants for both CYP1A1 polymorphisms were rare, risk estimates were imprecise. None of the other gene polymorphisms examined were associated with an earlier onset age for colorectal cancer. Our results suggest that the I462V and Msp1 polymorphisms in CYP1A1 may be an additional susceptibility factor for disease expression in Lynch syndrome since they modify the age of colorectal cancer onset by up to 4 years. PMID:18768509

Impact of CYP2C8*3 polymorphism on in vitro metabolism of imatinib to N-desmethyl imatinib.

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Khan, Muhammad Suleman; Barratt, Daniel T; Somogyi, Andrew A

2016-01-01

1. Imatinib is metabolized to N-desmethyl imatinib by CYPs 3A4 and 2C8. The effect of CYP2C8*3 genotype on N-desmethyl imatinib formation was unknown. 2. We examined imatinib N-demethylation in human liver microsomes (HLMs) genotyped for CYP2C8*3, in CYP2C8*3/*3 pooled HLMs and in recombinant CYP2C8 and CYP3A4 enzymes. Effects of CYP-selective inhibitors on N-demethylation were also determined. 3. A single-enzyme Michaelis-Menten model with autoinhibition best fitted CYP2C8*1/*1 HLM (n = 5) and recombinant CYP2C8 kinetic data (median ± SD Ki = 139 ± 61 µM and 149 µM, respectively). Recombinant CYP3A4 showed two-site enzyme kinetics with no autoinhibition. Three of four CYP2C8*1/*3 HLMs showed single-enzyme kinetics with no autoinhibition. Binding affinity was higher in CYP2C8*1/*3 than CYP2C8*1/*1 HLM (median ± SD Km = 6 ± 2 versus 11 ± 2 µM, P=0.04). CYP2C8*3/*3 (pooled HLM) also showed high binding affinity (Km = 4 µM) and single-enzyme weak autoinhibition (Ki = 449 µM) kinetics. CYP2C8 inhibitors reduced HLM N-demethylation by 47-75%, compared to 0-30% for CYP3A4 inhibitors. 4. In conclusion, CYP2C8*3 is a gain-of-function polymorphism for imatinib N-demethylation, which appears to be mainly mediated by CYP2C8 and not CYP3A4 in vitro in HLM.

Association between Two Resistin Gene Polymorphisms and Metabolic Syndrome in Jilin, Northeast China: A Case-Control Study

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Yingli Fu

2017-01-01

Full Text Available Metabolic syndrome (MetS is a significant health care problem worldwide and is characterized by increased fasting glucose and obesity. Resistin is a protein hormone produced both by adipocytes and immunocompetent cells, including those residing in adipose tissue, and is believed to modulate glucose tolerance and insulin action. This study examined the association of resistin gene polymorphisms, rs1862513 and rs3745368, and related haplotypes with the development of metabolic syndrome in a Han Chinese population. This case-control study was performed on 3792 subjects, including 1771 MetS cases and 2021 healthy controls from the Jilin province of China. Metabolic syndrome was defined according to the criteria of the International Diabetes Federation (IDF. Logistic regression analysis was used to estimate the relationship between gene polymorphism and MetS. Our results showed that there were no significant associations between MetS and the genotype distributions in four kinds of inheritance models, allele frequencies, and related haplotypes of resistin gene polymorphisms rs1862513 and rs3745368 (all p values > 0.05. Based on our study findings, we concluded that mutations in resistin genes are not associated with the presence of MetS in a Han Chinese population from Jilin province in China.

Polymorphism in the retinoic acid metabolizing enzyme CYP26B1 and the development of Crohn's Disease.

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Karin Fransén

Full Text Available Several studies suggest that Vitamin A may be involved in the pathogenesis of inflammatory bowel disease (IBD, but the mechanism is still unknown. Cytochrome P450 26 B1 (CYP26B1 is involved in the degradation of retinoic acid and the polymorphism rs2241057 has an elevated catabolic function of retinoic acid, why we hypothesized that the rs2241057 polymorphism may affect the risk of Crohn's disease (CD and Ulcerative Colitis (UC. DNA from 1378 IBD patients, divided into 871 patients with CD and 507 with UC, and 1205 healthy controls collected at Örebro University Hospital and Karolinska University Hospital were analyzed for the CYP26B1 rs2241057 polymorphism with TaqMan® SNP Genotyping Assay followed by allelic discrimination analysis. A higher frequency of patients homozygous for the major (T allele was associated with CD but not UC compared to the frequency found in healthy controls. A significant association between the major allele and non-stricturing, non-penetrating phenotype was evident for CD. However, the observed associations reached borderline significance only, after correcting for multiple testing. We suggest that homozygous carriers of the major (T allele, relative to homozygous carriers of the minor (C allele, of the CYP26B1 polymorphism rs2241057 may have an increased risk for the development of CD, which possibly may be due to elevated levels of retinoic acid. Our data may support the role of Vitamin A in the pathophysiology of CD, but the exact mechanisms remain to be elucidated.

Effects of naturally occurring coumarins on hepatic drug-metabolizing enzymes inmice

International Nuclear Information System (INIS)

Kleiner, Heather E.; Xia, Xiaojun; Sonoda, Junichiro; Zhang, Jun; Pontius, Elizabeth; Abey, Jane; Evans, Ronald M.; Moore, David D.; DiGiovanni, John

2008-01-01

Cytochromes P450 (P450s) and glutathione S-transferases (GSTs) constitute two important enzyme families involved in carcinogen metabolism. Generally, P450s play activation or detoxifying roles while GSTs act primarily as detoxifying enzymes. We previously demonstrated that oral administration of the linear furanocoumarins, isopimpinellin and imperatorin, modulated P450 and GST activities in various tissues of mice. The purpose of the present study was to compare a broader range of naturally occurring coumarins (simple coumarins, and furanocoumarins of the linear and angular type) for their abilities to modulate hepatic drug-metabolizing enzymes when administered orally to mice. We now report that all of the different coumarins tested (coumarin, limettin, auraptene, angelicin, bergamottin, imperatorin and isopimpinellin) induced hepatic GST activities, whereas the linear furanocoumarins possessed the greatest abilities to induce hepatic P450 activities, in particular P450 2B and 3A. In both cases, this corresponded to an increase in protein expression of the enzymes. Induction of P4502B10, 3A11, and 2C9 by xenobiotics often is a result of activation of the pregnane X receptor (PXR) and/or constitutive androstane receptor (CAR). Using a pregnane X receptor reporter system, our results demonstrated that isopimpinellin activated both PXR and its human ortholog SXR by recruiting coactivator SRC-1 in transfected cells. In CAR transfection assays, isopimpinellin counteracted the inhibitory effect of androstanol on full-length mCAR, a Gal4-mCAR ligand-binding domain fusion, and restored coactivator binding. Orally administered isopimpinellin induced hepatic mRNA expression of Cyp2b10, Cyp3a11, and GSTa in CAR(+/+) wild-type mice. In contrast, the induction of Cyp2b10 mRNA by isopimpinellin was attenuated in the CAR(-/-) mice, suggesting that isopimpinellin induces Cyp2b10 via the CAR receptor. Overall, the current data indicate that naturally occurring coumarins have

Angiotensin-converting enzyme I/D polymorphism in chronic obstructive pulmonary disease

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Pabst S

2009-12-01

Full Text Available Abstract Study objective The etiology of chronic obstructive lung disease (COPD is unclear. It is supposed to be the product of an exogenous antigenic stimulus, such as tobacco smoke, and an endogenous genetic susceptibility. The angiotensin-converting enzyme (ACE gene contains a polymorphism based on the presence (insertion [I] or absence (deletion [D] of a 287-bp nonsense domain, resulting in three different genotypes (II, ID and DD. The aim of the study was to find out whether the ACE gene polymorphism can determine the course of COPD. Patients and design We genotyped 152 Caucasian patients with COPD and 158 healthy controls for the ACE (I/D polymorphism. We divided the COPD group into one group of 64 patients with a stable course of disease, defined as less than three hospitalizations over the last three years due to COPD, and another group of 88 patients with an instable course with more than three hospitalizations. Results The I-allele was significantly associated with an increased risk for COPD in a dominant model (OR 1.67 (95% CI 1.00 to 2.78, p = 0.048, but not in a recessive or co-dominant model. Moreover, the I-allele of ACE (I/D was significantly increased in patients with a stable course of COPD (p = 0.012 compared with controls. In a dominant model (II/ID v DD we found an even stronger association between the I-allele and a stable course of COPD (OR 3.24 (95% CI 1.44 to 7.31, p = 0.003. Conclusion These data suggest that the presence of an ACE I-allele determines a stable course of COPD.

APOA2 Polymorphism in Relation to Obesity and Lipid Metabolism

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Moushira Erfan Zaki

2013-01-01

Full Text Available Objectives. This study aims to analysis the relationship between c.-492T>C polymorphism in APOA2 gene and the risk for obesity in a sample of Egyptian adolescents and investigates its effect on body fat distribution and lipid metabolism. Material and Methods. A descriptive, cross-sectional study was conducted on 303 adolescents. They were 196 obese and 107 nonobese, aged 16–19 years old. Variables examined included body mass index (BMI, waist circumference (WC, waist to hip ratio (WHR, systolic and diastolic blood pressure (BP, body fat percentage (BF%, abdominal visceral fat layer, and dietary intake. Abdominal visceral fat thickness was determined by ultrasonography. The polymorphism in the APOA2 c.-492T>C was analyzed by PCR amplification. Results. Genotype frequencies were in Hardy-Weinberg equilibrium. The frequency of the mutant C allele was significantly higher in obese cases compared to nonobese. After multivariate adjustment, waist, BF% and visceral adipose layer, food consumption, and HDL-C were significantly higher in homozygous allele CC carriers than TT+TC carriers. Conclusions. Homozygous individuals for the C allele had higher obesity risk than carriers of the T allele and had elevated levels of visceral adipose tissue and serum HDL-C. Moreover, the study shows association between the APOA2 c.-492T>C polymorphism and food consumption.

Can the genotype or phenotype of two polymorphic drug metabolising cytochrome P450-enzymes identify oral lichenoid drug eruptions?

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Kragelund, Camilla; Hansen, Claus; Reibel, Jesper

2010-01-01

Lichenoid drug eruptions (LDE) in the oral cavity are adverse drug reactions (ADR) that are impossible to differentiate from oral lichen planus (OLP) as no phenotypic criteria exist. Impaired function of polymorphic cytochrome 450-enzymes (CYPs) may cause increased plasma concentration of some...

Highlighting the Need for Systems-level Experimental Characterization of Plant Metabolic Enzymes

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Martin Karl Magnus Engqvist

2016-07-01

Full Text Available The biology of living organisms is determined by the action and interaction of a large number of individual gene products, each with specific functions. Discovering and annotating the function of gene products is key to our understanding of these organisms. Controlled experiments and bioinformatic predictions both contribute to functional gene annotation. For most species it is difficult to gain an overview of what portion of gene annotations are based on experiments and what portion represent predictions. Here, I survey the current state of experimental knowledge of enzymes and metabolism in Arabidopsis thaliana as well as eleven economically important crops and forestry trees – with a particular focus on reactions involving organic acids in central metabolism. I illustrate the limited availability of experimental data for functional annotation of enzymes in most of these species. Many enzymes involved in metabolism of citrate, malate, fumarate, lactate, and glycolate in crops and forestry trees have not been characterized. Furthermore, enzymes involved in key biosynthetic pathways which shape important traits in crops and forestry trees have not been characterized. I argue for the development of novel high-throughput platforms with which limited functional characterization of gene products can be performed quickly and relatively cheaply. I refer to this approach as systems-level experimental characterization. The data collected from such platforms would form a layer intermediate between bioinformatic gene function predictions and in-depth experimental studies of these functions. Such a data layer would greatly aid in the pursuit of understanding a multiplicity of biological processes in living organisms.

Phase I metabolic genes and risk of lung cancer: multiple polymorphisms and mRNA expression.

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Melissa Rotunno

2009-05-01

Full Text Available Polymorphisms in genes coding for enzymes that activate tobacco lung carcinogens may generate inter-individual differences in lung cancer risk. Previous studies had limited sample sizes, poor exposure characterization, and a few single nucleotide polymorphisms (SNPs tested in candidate genes. We analyzed 25 SNPs (some previously untested in 2101 primary lung cancer cases and 2120 population controls from the Environment And Genetics in Lung cancer Etiology (EAGLE study from six phase I metabolic genes, including cytochrome P450s, microsomal epoxide hydrolase, and myeloperoxidase. We evaluated the main genotype effects and genotype-smoking interactions in lung cancer risk overall and in the major histology subtypes. We tested the combined effect of multiple SNPs on lung cancer risk and on gene expression. Findings were prioritized based on significance thresholds and consistency across different analyses, and accounted for multiple testing and prior knowledge. Two haplotypes in EPHX1 were significantly associated with lung cancer risk in the overall population. In addition, CYP1B1 and CYP2A6 polymorphisms were inversely associated with adenocarcinoma and squamous cell carcinoma risk, respectively. Moreover, the association between CYP1A1 rs2606345 genotype and lung cancer was significantly modified by intensity of cigarette smoking, suggesting an underlying dose-response mechanism. Finally, increasing number of variants at CYP1A1/A2 genes revealed significant protection in never smokers and risk in ever smokers. Results were supported by differential gene expression in non-tumor lung tissue samples with down-regulation of CYP1A1 in never smokers and up-regulation in smokers from CYP1A1/A2 SNPs. The significant haplotype associations emphasize that the effect of multiple SNPs may be important despite null single SNP-associations, and warrants consideration in genome-wide association studies (GWAS. Our findings emphasize the necessity of post

Metabolic enzyme microarray coupled with miniaturized cell-culture array technology for high-throughput toxicity screening.

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Lee, Moo-Yeal; Dordick, Jonathan S; Clark, Douglas S

2010-01-01

Due to poor drug candidate safety profiles that are often identified late in the drug development process, the clinical progression of new chemical entities to pharmaceuticals remains hindered, thus resulting in the high cost of drug discovery. To accelerate the identification of safer drug candidates and improve the clinical progression of drug candidates to pharmaceuticals, it is important to develop high-throughput tools that can provide early-stage predictive toxicology data. In particular, in vitro cell-based systems that can accurately mimic the human in vivo response and predict the impact of drug candidates on human toxicology are needed to accelerate the assessment of drug candidate toxicity and human metabolism earlier in the drug development process. The in vitro techniques that provide a high degree of human toxicity prediction will be perhaps more important in cosmetic and chemical industries in Europe, as animal toxicity testing is being phased out entirely in the immediate future.We have developed a metabolic enzyme microarray (the Metabolizing Enzyme Toxicology Assay Chip, or MetaChip) and a miniaturized three-dimensional (3D) cell-culture array (the Data Analysis Toxicology Assay Chip, or DataChip) for high-throughput toxicity screening of target compounds and their metabolic enzyme-generated products. The human or rat MetaChip contains an array of encapsulated metabolic enzymes that is designed to emulate the metabolic reactions in the human or rat liver. The human or rat DataChip contains an array of 3D human or rat cells encapsulated in alginate gels for cell-based toxicity screening. By combining the DataChip with the complementary MetaChip, in vitro toxicity results are obtained that correlate well with in vivo rat data.

The importance of association between angiotensin-converting enzyme (ACE) Gene I/D polymorphism and diabetic peripheral neuropathy.

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Inanir, Ahmet; Basol, Nursah; Karakus, Nevin; Yigit, Serbulent

2013-11-10

Diabetic peripheral neuropathy (DPN) is a microvascular complication of diabetes mellitus (DM) due to decreasing quality of life. In the present study, it is aimed to evaluate angiotensin-converting enzyme (ACE) Gene I/D polymorphism in Turkish population. Two hundred and thirty-five DPN patients and two hundred and eighty-one controls were enrolled in this study. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses for the ACE gene I/D polymorphism. Baseline characteristics of the DPN patients according to ACE genotypes were similar, except for history of hypertension. The frequency of II genotype was significantly higher in patients with positive history of hypertension than the patients with negative history of hypertension (p=0.013). DD genotype of I/D polymorphism was found to be a susceptibility factor for DPN in homozygous form (p=0.032). According to allele frequencies, D allele of I/D polymorphism was found to be a susceptibility factor for DPN (p=0.031). ACE gene I/D polymorphism may research in DM patients to determine genetic predisposition for DPN. It can be useful for taking early measures and avoiding DPN in a Turkish population. © 2013 Elsevier B.V. All rights reserved.

Molecular characterization and polymorphisms of butyrylcholinesterase in cynomolgus macaques.

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Uno, Yasuhiro; Uehara, Shotaro; Mahadhi, Hassan M D; Ohura, Kayoko; Hosokawa, Masakiyo; Imai, Teruko

2018-06-01

Butyrylcholinesterase (BChE), an enzyme essential for drug metabolism, has been investigated as antidotes against organophosphorus nerve agents, and the efficacy and safety have been studied in cynomolgus macaques. BChE polymorphisms partly account for variable BChE activities among individuals in humans, but have not been investigated in cynomolgus macaques. Molecular characterization was carried out by analyzing primary sequence, gene, tissue expression, and genetic variants. In cynomolgus and human BChE, phylogenetically closely related, amino acid residues important for enzyme function were conserved, and gene and genomic structure were similar. Cynomolgus BChE mRNA was most abundantly expressed in liver among the 10 tissue types analyzed. Re-sequencing found 26 non-synonymous genetic variants in 121 cynomolgus and 23 rhesus macaques, indicating that macaque BChE is polymorphic, although none of these variants corresponded to the null or defective alleles of human BChE. These results suggest molecular similarities of cynomolgus and human BChE. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Association between the HTR2C rs1414334 C/G gene polymorphism and the development of the metabolic syndrome in patients treated with atypical antipsychotics

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José María Rico-Gomis

2016-07-01

Full Text Available Few studies have assessed the association between the rs1414334 C/G polymorphism in the HTR2C gene and the development of the metabolic syndrome in patients treated with atypical antipsychotics. To provide further evidence, a cross-sectional study was conducted in Spain between 2012 and 2013 in 166 patients with these characteristics. In these patients, the association between the polymorphism and the presence of the metabolic syndrome was determined by implementing binary logistic regression models adjusted for variables associated with the metabolic syndrome. We did not confirm previous claims that the C allele of the polymorphism was linked to the metabolic syndrome: the association was in the opposite direction and non-significant. This conclusion held after taking gender and lifestyle variables into account.

Single nucleotide polymorphisms of the angiotensin-converting enzyme (ACE) gene are associated with essential hypertension and increased ACE enzyme levels in Mexican individuals.

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Martínez-Rodríguez, Nancy; Posadas-Romero, Carlos; Villarreal-Molina, Teresa; Vallejo, Maite; Del-Valle-Mondragón, Leonardo; Ramírez-Bello, Julian; Valladares, Adan; Cruz-López, Miguel; Vargas-Alarcón, Gilberto

2013-01-01

To explore the role of the ACE gene polymorphisms in the risk of essential hypertension in Mexican Mestizo individuals and evaluate the correlation between these polymorphisms and the serum ACE levels. Nine ACE gene polymorphisms were genotyped by 5' exonuclease TaqMan genotyping assays and polymerase chain reaction (PCR) in 239 hypertensive and 371 non- hypertensive Mexican individuals. Haplotypes were constructed after linkage disequilibrium analysis. ACE serum levels were determined in selected individuals according to different haplotypes. Under a dominant model, rs4291 rs4335, rs4344, rs4353, rs4362, and rs4363 polymorphisms were associated with an increased risk of hypertension after adjusting for age, gender, BMI, triglycerides, alcohol consumption, and smoking. Five polymorphisms (rs4335, rs4344, rs4353, rs4362 and rs4363) were in strong linkage disequilibrium and were included in four haplotypes: H1 (AAGCA), H2 (GGATG), H3 (AGATG), and H4 (AGACA). Haplotype H1 was associated with decreased risk of hypertension, while haplotype H2 was associated with an increased risk of hypertension (OR = 0.77, P = 0.023 and OR = 1.41, P = 0.004 respectively). According to the codominant model, the H2/H2 and H1/H2 haplotype combinations were significantly associated with risk of hypertension after adjusted by age, gender, BMI, triglycerides, alcohol consumption, and smoking (OR = 2.0; P = 0.002 and OR = 2.09; P = 0.011, respectively). Significant elevations in serum ACE concentrations were found in individuals with the H2 haplotype (H2/H2 and H2/H1) as compared to H1/H1 individuals (P = 0.0048). The results suggest that single nucleotide polymorphisms and the "GGATG" haplotype of the ACE gene are associated with the development of hypertension and with increased ACE enzyme levels.

Angiotensin-Converting Enzyme Gene Insertion/Deletion Polymorphism and Small Vessel Cerebral Stroke in Indian Population

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Puttachandra Prabhakar

2014-01-01

Full Text Available Background. Hypertension is an established risk factor for small-vessel cerebral stroke and the renin-angiotensin system plays an important role in the maintenance of blood pressure. We aimed at evaluating the contribution of the angiotensin-converting enzyme (ACE gene insertion/deletion (I/D polymorphism to the risk of small-vessel stroke in south Indian population. Materials and Methods. We investigated 128 patients diagnosed with small-vessel stroke and 236 age, and gender-matched healthy controls. ACE I/D polymorphism was detected by polymerase chain reaction. Results. Hypertension was significantly more prevalent in the patient group and was associated with 6-fold increase in risk for stroke. ACE genotypes were in Hardy-Weinberg equilibrium in both patients and controls. Prevalence of DD, ID, and II genotypes in cases (34.4%, 43.7%, and 28% did not differ significantly from controls (31.8%, 43.2%, and 25%. The polymorphism was not associated with small-vessel stroke (OR: 1.34; 95% CI: 0.52–1.55. However, diastolic blood pressure was associated with the ACE I/D genotypes in the patients. (DD; 90.2±14.2> ID; 86.2±11.9> II; 82.3±7.8 mm Hg,  P=0.047. Conclusion. Our study showed that hypertension, but not ACE I/D polymorphism, increased the risk of small-vessel stroke.

Etiological classification of depression based on the enzymes of tryptophan metabolism.

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Fukuda, Katsuhiko

2014-12-24

Viewed in terms of input and output, the mechanisms of depression are still akin to a black box. However, there must be main pivots for diverse types of depression. From recent therapeutic observations, both the serotonin (5-HT) and kynurenine pathways of tryptophan metabolism may be of particular importance to improved understanding of depression. Here, I propose an etiological classification of depression, based on key peripheral and central enzymes of tryptophan metabolism. Endogenous depression is caused by a larger genetic component than reactive depression. Besides enterochromaffin and mast cells, tryptophan hydroxylase 1 (TPH1), primarily expressed in the gastrointestinal tract, is also found in 5-hydroxytryptophan-producing cells (5-HTP cells) in normal intestinal enterocytes, which are thought to essentially shunt 5-HT production in 5-HT-producing cells. Genetic studies have reported an association between TPH1 and depression, or the responsiveness of depression to antidepressive medication. Therefore, it is possible that hypofunctional 5-HTP cells (reflecting TPH1 dysfunction) in the periphery lead to deficient brain 5-HT levels. Additionally,it has been reported that higher TPH2 expression in depressed suicides may reflect a homeostatic response to deficient 5-HT levels. Subsequently, endogenous depression may be caused by TPH1 dysfunction combined with compensatory TPH2 activation. Reactive depression results from life stresses and involves the hypothalamic-pituitary-adrenal axis, with resulting cortisol production inducing tryptophan 2,3-dioxygenase (TDO) activation. In secondary depression, caused by inflammation, infection, or oxidative stress, indoleamine 2,3-dioxygenase (IDO) is activated. In both reactive and secondary depression, the balance between 3-hydroxykynurenine (3-HK) and kynurenic acid may shift towards 3-HK production via kynurenine-3-monooxygenase (KMO) activation. By shifting the equilibrium position of key enzymes of tryptophan

Polymorphisms in metabolism and repair genes affects DNA damage caused by open-cast coal mining exposure.

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Espitia-Pérez, Lyda; Sosa, Milton Quintana; Salcedo-Arteaga, Shirley; León-Mejía, Grethel; Hoyos-Giraldo, Luz Stella; Brango, Hugo; Kvitko, Katia; da Silva, Juliana; Henriques, João A P

2016-09-15

Increasing evidence suggest that occupational exposure to open-cast coal mining residues like dust particles, heavy metals and Polycyclic Aromatic Hydrocarbons (PAHs) may cause a wide range of DNA damage and genomic instability that could be associated to initial steps in cancer development and other work-related diseases. The aim of our study was to evaluate if key polymorphisms in metabolism genes CYP1A1Msp1, GSTM1Null, GSTT1Null and DNA repair genes XRCC1Arg194Trp and hOGG1Ser326Cys could modify individual susceptibility to adverse coal exposure effects, considering the DNA damage (Comet assay) and micronucleus formation in lymphocytes (CBMN) and buccal mucosa cells (BMNCyt) as endpoints for genotoxicity. The study population is comprised of 200 healthy male subjects, 100 open-cast coal-mining workers from "El Cerrejón" (world's largest open-cast coal mine located in Guajira - Colombia) and 100 non-exposed referents from general population. The data revealed a significant increase of CBMN frequency in peripheral lymphocytes of occupationally exposed workers carrying the wild-type variant of GSTT1 (+) gene. Exposed subjects carrying GSTT1null polymorphism showed a lower micronucleus frequency compared with their positive counterparts (FR: 0.83; P=0.04), while BMNCyt, frequency and Comet assay parameters in lymphocytes: Damage Index (DI) and percentage of DNA in the tail (Tail % DNA) were significantly higher in exposed workers with the GSTM1Null polymorphism. Other exfoliated buccal mucosa abnormalities related to cell death (Karyorrhexis and Karyolysis) were increased in GSTT/M1Null carriers. Nuclear buds were significantly higher in workers carrying the CYP1A1Msp1 (m1/m2, m2/m2) allele. Moreover, BMNCyt frequency and Comet assay parameters were significantly lower in exposed carriers of XRCC1Arg194Trp (Arg/Trp, Trp/Trp) and hOGG1Ser326Cys (Ser/Cys, Cys/Cys), thereby providing new data to the increasing evidence about the protective role of these polymorphisms

mRNA levels of enzymes and receptors implicated in arachidonic acid metabolism in gliomas.

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De Armas, Rafael; Durand, Karine; Guillaudeau, Angélique; Weinbreck, Nicolas; Robert, Sandrine; Moreau, Jean-Jacques; Caire, François; Acosta, Gisela; Pebet, Matias; Chaunavel, Alain; Marin, Benoît; Labrousse, François; Denizot, Yves

2010-07-01

Gliomas are tumors of the central nervous system derived from glial cells. They show cellular heterogeneity and lack specific diagnostic markers. Although a possible role for the eicosanoid cascade has been suggested in glioma tumorigenesis, the relationship between enzymes and receptors implicated in arachidonic acid metabolism, with histological tumor type has not yet been determined. Quantitative real-time reverse transcription-polymerase chain reaction was performed to measure and compare transcript levels of enzymes and receptors implicated in both lipoxygenase and cyclooxygenase pathways between oligodendrogliomas, astrocytomas, glioblastomas and mixed oligoastrocytomas. Arachidonic acid metabolism-related enzymes and receptor transcripts (i) were underexpressed in classical oligodendrogliomas compared to astrocytomas and/or glioblastomas, (ii) differed between astrocytomas and glioblastomas and (iii) had an intermediate expression in mixed oligoastrocytomas. mRNA levels of enzymes and receptors implicated both in lipoxygenase and cyclooxygenase pathways differed significantly in gliomas according to the histological type. Copyright 2010 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Lack of Association of Estrogen Receptor Alpha Gene Polymorphisms with Cardiorespiratory and Metabolic Variables in Young Women

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Mario Hirata

2012-10-01

Full Text Available This study examined the association of estrogen receptor alpha gene (ESR1 polymorphisms with cardiorespiratory and metabolic parameters in young women. In total, 354 healthy women were selected for cardiopulmonary exercise testing and short-term heart rate (HR variability (HRV evaluation. The HRV analysis was determined by the temporal indices rMSSD (square root of the mean squared differences of successive R–R intervals (RRi divided by the number of RRi minus one, SDNN (root mean square of differences from mean RRi, divided by the number of RRi and power spectrum components by low frequency (LF, high frequency (HF and LF/HF ratio. Blood samples were obtained for serum lipids, estradiol and DNA extraction. ESR1 rs2234693 and rs9340799 polymorphisms were analyzed by PCR and fragment restriction analysis. HR and oxygen uptake (VO2 values did not differ between the ESR1 polymorphisms with respect to autonomic modulation. We not find a relationship between ESR1 T–A, T–G, C–A and C–G haplotypes and cardiorespiratory and metabolic variables. Multiple linear regression analysis demonstrated that VO2, total cholesterol and triglycerides influence HRV (p < 0.05. The results suggest that ESR1 variants have no effect on cardiorespiratory and metabolic variables, while HRV indices are influenced by aerobic capacity and lipids in healthy women.

Genetic Polymorphism of Angiotensin-Converting Enzyme and Chronic Obstructive Pulmonary Disease Risk: An Updated Meta-Analysis

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Sang Wook Kang

2016-01-01

Full Text Available The relationship between polymorphism of the angiotensin I converting enzyme (ACE gene and chronic obstructive pulmonary disease (COPD has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR, and 95% confidence interval (95% CI were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p>0.05 in each model. In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p0.05 in each model. In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample.

Angiotensin-converting enzyme gene insertion/deletion polymorphism studies in Asian Indian pregnant women biochemically identifies gestational diabetes mellitus.

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Khan, Imran A; Jahan, Parveen; Hasan, Qurratulain; Rao, Pragna

2014-12-01

Gestational diabetes mellitus (GDM) is defined as glucose intolerance first recognized during pregnancy. Insertion/deletion (I/D) polymorphism of a 287 bp Alu repetitive sequence in intron 16 of the angiotensin-converting enzyme (ACE) gene has been widely investigated in Asian Indian populations with different ethnic origins. The present study examined possible association between I/D polymorphism of the ACE gene and GDM in Asian Indian pregnant women. A total of 200 pregnant women (100 GDM and 100 non-GDM) were recruited in this study and I/D polymorphism of a 287 bp Alu1 element inside intron 16 of the ACE gene was examined by polymerase chain reaction (PCR)-based gel electrophoresis. The distribution of the variants like II, ID, and DD genotypes of ACE gene showed differences between normal GDM versus non-GDM subjects, and the frequency of the ID+ DD Vs II genotype was significant (p=0.0002) in the GDM group. ACE gene polymorphism was associated with GDM in Asian Indian pregnant women. © The Author(s) 2013.

The Association of Polymorphisms in Leptin/Leptin Receptor Genes and Ghrelin/Ghrelin Receptor Genes With Overweight/Obesity and the Related Metabolic Disturbances: A Review.

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Ghalandari, Hamid; Hosseini-Esfahani, Firoozeh; Mirmiran, Parvin

2015-07-01

Leptin and ghrelin are two important appetite and energy balance-regulating peptides. Common polymorphisms in the genes coding these peptides and their related receptors are shown to be associated with body weight, different markers of obesity and metabolic abnormalities. This review article aims to investigate the association of common polymorphisms of these genes with overweight/obesity and the metabolic disturbances related to it. The keywords leptin, ghrelin, polymorphism, single-nucleotide polymorphism (SNP), obesity, overweight, Body Mass Index, metabolic syndrome, and type 2 diabetes mellitus (T2DM) (MeSH headings) were used to search in the following databases: Pubmed, Sciencedirect (Elsevier), and Google scholar. Overall, 24 case-control studies, relevant to our topic, met the criteria and were included in the review. The most prevalent leptin/leptin receptor genes (LEP/LEPR) and ghrelin/ghrelin receptor genes (GHRL/GHSR) single nucleotide polymorphisms studied were LEP G-2548A, LEPR Q223R, and Leu72Met, respectively. Nine studies of the 17 studies on LEP/LEPR, and three studies of the seven studies on GHRL/GHSR showed significant relationships. In general, our study suggests that the association between LEP/LEPR and GHRL/GHSR with overweight/obesity and the related metabolic disturbances is inconclusive. These results may be due to unidentified gene-environment interactions. More investigations are needed to further clarify this association.

Current knowledge of microRNA-mediated regulation of drug metabolism in humans.

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Nakano, Masataka; Nakajima, Miki

2018-05-01

Understanding the factors causing inter- and intra-individual differences in drug metabolism potencies is required for the practice of personalized or precision medicine, as well as for the promotion of efficient drug development. The expression of drug-metabolizing enzymes is controlled by transcriptional regulation by nuclear receptors and transcriptional factors, epigenetic regulation, such as DNA methylation and histone acetylation, and post-translational modification. In addition to such regulation mechanisms, recent studies revealed that microRNAs (miRNAs), endogenous ~22-nucleotide non-coding RNAs that regulate gene expression through the translational repression and degradation of mRNAs, significantly contribute to post-transcriptional regulation of drug-metabolizing enzymes. Areas covered: This review summarizes the current knowledge regarding miRNAs-dependent regulation of drug-metabolizing enzymes and transcriptional factors and its physiological and clinical significance. We also describe recent advances in miRNA-dependent regulation research, showing that the presence of pseudogenes, single-nucleotide polymorphisms, and RNA editing affects miRNA targeting. Expert opinion: It is unwavering fact that miRNAs are critical factors causing inter- and intra-individual differences in the expression of drug-metabolizing enzymes. Consideration of miRNA-dependent regulation would be a helpful tool for optimizing personalized and precision medicine.

The association of polymorphisms in 5-fluorouracil metabolism genes with outcome in adjuvant treatment of colorectal cancer

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Shoaib, Afzal; Gusella, Milena; Jensen, Søren Astrup

2011-01-01

The purpose of this study was to investigate whether specific combinations of polymorphisms in 5-fluorouracil (5-FU) metabolism-related genes were associated with outcome in 5-FU-based adjuvant treatment of colorectal cancer....

Pharmacogenetics of aldo-keto reductase 1C (AKR1C) enzymes.

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Alshogran, Osama Y

2017-10-01

Genetic variation in metabolizing enzymes contributes to variable drug response and disease risk. Aldo-keto reductase type 1C (AKR1C) comprises a sub-family of reductase enzymes that play critical roles in the biotransformation of various drug substrates and endogenous compounds such as steroids. Several single nucleotide polymorphisms have been reported among AKR1C encoding genes, which may affect the functional expression of the enzymes. Areas covered: This review highlights and comprehensively discusses previous pharmacogenetic reports that have examined genetic variations in AKR1C and their association with disease development, drug disposition, and therapeutic outcomes. The article also provides information about the effect of AKR1C genetic variants on enzyme function in vitro. Expert opinion: The current evidence that links the effect of AKR1C gene polymorphisms to disease progression and development is inconsistent and needs further validation, despite of the tremendous knowledge available. Information about association of AKR1C genetic variants and drug efficacy, safety, and pharmacokinetics is limited, thus, future studies that advance our understanding about these relationships and their clinical relevance are needed. It is imperative to achieve consistent findings before the potential translation and adoption of AKR1C genetic variants in clinical practice.

The Association of Polymorphisms in Leptin/Leptin Receptor Genes and Ghrelin/Ghrelin Receptor Genes With Overweight/Obesity and the Related Metabolic Disturbances: A Review

OpenAIRE

Ghalandari; Hosseini-Esfahani; Mirmiran

2015-01-01

Context Leptin and ghrelin are two important appetite and energy balance-regulating peptides. Common polymorphisms in the genes coding these peptides and their related receptors are shown to be associated with body weight, different markers of obesity and metabolic abnormalities. This review article aims to investigate the association of common polymorphisms of these genes with overweight/obesity and the metabolic disturbances related to it. E...

Increments and duplication events of enzymes and transcription factors influence metabolic and regulatory diversity in prokaryotes.

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Mario Alberto Martínez-Núñez

Full Text Available In this work, the content of enzymes and DNA-binding transcription factors (TFs in 794 non-redundant prokaryotic genomes was evaluated. The identification of enzymes was based on annotations deposited in the KEGG database as well as in databases of functional domains (COG and PFAM and structural domains (Superfamily. For identifications of the TFs, hidden Markov profiles were constructed based on well-known transcriptional regulatory families. From these analyses, we obtained diverse and interesting results, such as the negative rate of incremental changes in the number of detected enzymes with respect to the genome size. On the contrary, for TFs the rate incremented as the complexity of genome increased. This inverse related performance shapes the diversity of metabolic and regulatory networks and impacts the availability of enzymes and TFs. Furthermore, the intersection of the derivatives between enzymes and TFs was identified at 9,659 genes, after this point, the regulatory complexity grows faster than metabolic complexity. In addition, TFs have a low number of duplications, in contrast to the apparent high number of duplications associated with enzymes. Despite the greater number of duplicated enzymes versus TFs, the increment by which duplicates appear is higher in TFs. A lower proportion of enzymes among archaeal genomes (22% than in the bacterial ones (27% was also found. This low proportion might be compensated by the interconnection between the metabolic pathways in Archaea. A similar proportion was also found for the archaeal TFs, for which the formation of regulatory complexes has been proposed. Finally, an enrichment of multifunctional enzymes in Bacteria, as a mechanism of ecological adaptation, was detected.

BClI polymorphism of the glucocorticoid receptor gene is associated with increased obesity, impaired glucose metabolism and dyslipidaemia in patients with Addison's disease.

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Giordano, Roberta; Marzotti, Stefania; Berardelli, Rita; Karamouzis, Ioannis; Brozzetti, Annalisa; D'Angelo, Valentina; Mengozzi, Giulio; Mandrile, Giorgia; Giachino, Daniela; Migliaretti, Giuseppe; Bini, Vittorio; Falorni, Alberto; Ghigo, Ezio; Arvat, Emanuela

2012-12-01

Although glucocorticoids are essential for health, several studies have shown that glucocorticoids replacement in Addison's disease might be involved in anthropometric and metabolic impairment, with increased cardiovascular risk, namely if conventional doses are used. As the effects of glucocorticoids are mediated by the glucocorticoid receptor, encoded by NR3C1 gene, different polymorphisms in the NR3C1 gene have been linked to altered glucocorticoid sensitivity in general population as well as in patients with obesity or metabolic syndrome. We investigated the impact of glucocorticoid receptor gene polymorphisms, including the BclI, N363S and ER22/23EK variants, on anthropometric parameters (BMI and waist circumference), metabolic profile (HOMA, OGTT and serum lipids) and ACTH levels in 50 patients with Addison's disease (34 women and 16 men, age 20-82 year) under glucocorticoids replacement. Neither N363S nor ER22/23EK variants were significantly associated with anthropometric, metabolic or hormonal parameters, while patients carrying the homozygous BclI polymorphism GG (n = 4) showed higher (P Addison's disease and may contribute, along with other factors, to the increase in central adiposity, impaired glucose metabolism and dyslipidaemia. © 2012 Blackwell Publishing Ltd.

Molecular docking studies of 3-bromopyruvate and its derivatives to metabolic regulatory enzymes: Implication in designing of novel anticancer therapeutic strategies.

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Yadav, Saveg; Pandey, Shrish Kumar; Singh, Vinay Kumar; Goel, Yugal; Kumar, Ajay; Singh, Sukh Mahendra

2017-01-01

Altered metabolism is an emerging hallmark of cancer, as malignant cells display a mammoth up-regulation of enzymes responsible for steering their bioenergetic and biosynthetic machinery. Thus, the recent anticancer therapeutic strategies focus on the targeting of metabolic enzymes, which has led to the identification of specific metabolic inhibitors. One of such inhibitors is 3-bromopyruvate (3-BP), with broad spectrum of anticancer activity due to its ability to inhibit multiple metabolic enzymes. However, the molecular characterization of its binding to the wide spectrum of target enzymes remains largely elusive. Therefore, in the present study we undertook in silico investigations to decipher the molecular nature of the docking of 3-BP with key target enzymes of glycolysis and TCA cycle by PatchDock and YASARA docking tools. Additionally, derivatives of 3-BP, dibromopyruvate (DBPA) and propionic acid (PA), with reported biological activity, were also investigated for docking to important target metabolic enzymes of 3-BP, in order to predict their therapeutic efficacy versus that of 3-BP. A comparison of the docking scores with respect to 3-BP indicated that both of these derivatives display a better binding strength to metabolic enzymes. Further, analysis of the drug likeness of 3-BP, DBPA and PA by Lipinski filter, admetSAR and FAF Drug3 indicated that all of these agents showed desirable drug-like criteria. The outcome of this investigation sheds light on the molecular characteristics of the binding of 3-BP and its derivatives with metabolic enzymes and thus may significantly contribute in designing and optimizing therapeutic strategies against cancer by using these agents.

Molecular docking studies of 3-bromopyruvate and its derivatives to metabolic regulatory enzymes: Implication in designing of novel anticancer therapeutic strategies.

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Saveg Yadav

Full Text Available Altered metabolism is an emerging hallmark of cancer, as malignant cells display a mammoth up-regulation of enzymes responsible for steering their bioenergetic and biosynthetic machinery. Thus, the recent anticancer therapeutic strategies focus on the targeting of metabolic enzymes, which has led to the identification of specific metabolic inhibitors. One of such inhibitors is 3-bromopyruvate (3-BP, with broad spectrum of anticancer activity due to its ability to inhibit multiple metabolic enzymes. However, the molecular characterization of its binding to the wide spectrum of target enzymes remains largely elusive. Therefore, in the present study we undertook in silico investigations to decipher the molecular nature of the docking of 3-BP with key target enzymes of glycolysis and TCA cycle by PatchDock and YASARA docking tools. Additionally, derivatives of 3-BP, dibromopyruvate (DBPA and propionic acid (PA, with reported biological activity, were also investigated for docking to important target metabolic enzymes of 3-BP, in order to predict their therapeutic efficacy versus that of 3-BP. A comparison of the docking scores with respect to 3-BP indicated that both of these derivatives display a better binding strength to metabolic enzymes. Further, analysis of the drug likeness of 3-BP, DBPA and PA by Lipinski filter, admetSAR and FAF Drug3 indicated that all of these agents showed desirable drug-like criteria. The outcome of this investigation sheds light on the molecular characteristics of the binding of 3-BP and its derivatives with metabolic enzymes and thus may significantly contribute in designing and optimizing therapeutic strategies against cancer by using these agents.

The evaluation of angiotensin-converting enzyme (ACE) gene I/D and IL-4 gene intron 3 VNTR polymorphisms in coronary artery disease.

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Basol, Nursah; Celik, Atac; Karakus, Nevin; Ozturk, Sibel Demir; Ozsoy, Sibel Demir; Yigit, Serbulent

2014-01-01

Genetic polymorphism is a strong risk factor for coronary artery disease (CAD). In the present study, our aim was to evaluate angiotensin-converting enzyme (ACE) gene I/D polymorphism and interleukin-4 (IL-4) gene Intron 3 variable number of tandem repeat (VNTR) polymorphism in CAD. One hundred and twenty-four CAD patients and one hundred and twenty-three controls were enrolled. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR) analyses. The risk associated with inheriting the combined genotypes for the two polymorphisms were evaluated and it was found that the individuals who were P2P2-homozygous at IL-4 gene intron 3 VNTR and DD-homozygous at ACE gene I/D have a higher risk of developing CAD. Although, there is no correlation between IL4 VNTR polymorphism and ACE gene polymorphism and CAD, there is a strong association between CAD and co-existence of IL-4 VNTR and ACE gene polymorphisms in the Turkish population. Copyright © 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

An MRM-based workflow for absolute quantitation of lysine-acetylated metabolic enzymes in mouse liver.

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Xu, Leilei; Wang, Fang; Xu, Ying; Wang, Yi; Zhang, Cuiping; Qin, Xue; Yu, Hongxiu; Yang, Pengyuan

2015-12-07

As a key post-translational modification mechanism, protein acetylation plays critical roles in regulating and/or coordinating cell metabolism. Acetylation is a prevalent modification process in enzymes. Protein acetylation modification occurs in sub-stoichiometric amounts; therefore extracting biologically meaningful information from these acetylation sites requires an adaptable, sensitive, specific, and robust method for their quantification. In this work, we combine immunoassays and multiple reaction monitoring-mass spectrometry (MRM-MS) technology to develop an absolute quantification for acetylation modification. With this hybrid method, we quantified the acetylation level of metabolic enzymes, which could demonstrate the regulatory mechanisms of the studied enzymes. The development of this quantitative workflow is a pivotal step for advancing our knowledge and understanding of the regulatory effects of protein acetylation in physiology and pathophysiology.

Interplay of Drug-Metabolizing Enzymes and Transporters in Drug Absorption and Disposition.

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Shi, Shaojun; Li, Yunqiao

2014-01-01

In recent years, the functional interplay between drug-metabolizing enzymes (DMEs) and drug transporters (DTs) in drug absorption and disposition, as well as the complex drug interactions (DIs), has become an intriguing contention, which has also been termed the "transport-metabolism interplay". The current mechanistic understanding for this interplay is first discussed. In the present article, studies investigating the interplay between cytochrome P450 enzymes (CYPs) and efflux transporters have been systematically reviewed in vitro, in situ, in silico, in animals and humans, followed by CYPs-uptake transporters, CYPs-uptake transporters-efflux transporters, and phase II metabolic enzymes-transporters interplay studies. Although several cellular, isolated organ and whole animal studies, in conjunction with simulation and modelling, have addressed the issue that DMEs and DTs can work cooperatively to affect the bioavailability of shared substrate drugs, convincing evidences in human studies are still lacking. Furthermore, the functional interplay between DMEs and DTs will be highly substrate- and dose- dependent. Additionally, we review recent studies to evaluate the influence of genetic variations in the interplay between DMEs and DTs, which might be helpful for the prediction of pharmacokinetics (PK) and possible DIs in human more correctly. There is strong evidence of coordinately regulated DEMs and DTs gene expression and protein activity (e.g. nuclear receptors). Taken together, further investigations and analysis are urgently needed to explore the functional interplay of DMEs and DTs and to delineate the underlying mechanisms.

Fluvoxamine alters the activity of energy metabolism enzymes in the brain

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Gabriela K. Ferreira

2014-09-01

Full Text Available Objective: Several studies support the hypothesis that metabolism impairment is involved in the pathophysiology of depression and that some antidepressants act by modulating brain energy metabolism. Thus, we evaluated the activity of Krebs cycle enzymes, the mitochondrial respiratory chain, and creatine kinase in the brain of rats subjected to prolonged administration of fluvoxamine. Methods: Wistar rats received daily administration of fluvoxamine in saline (10, 30, and 60 mg/kg for 14 days. Twelve hours after the last administration, rats were killed by decapitation and the prefrontal cortex, cerebral cortex, hippocampus, striatum, and cerebellum were rapidly isolated. Results: The activities of citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV were decreased after prolonged administration of fluvoxamine in rats. However, the activities of complex II, succinate dehydrogenase, and creatine kinase were increased. Conclusions: Alterations in activity of energy metabolism enzymes were observed in most brain areas analyzed. Thus, we suggest that the decrease in citrate synthase, malate dehydrogenase, and complexes I, II-III, and IV can be related to adverse effects of pharmacotherapy, but long-term molecular adaptations cannot be ruled out. In addition, we demonstrated that these changes varied according to brain structure or biochemical analysis and were not dose-dependent.

Gamma radiation induced alterations in the ultrastructure of pancreatic islet, metabolism and enzymes in wistar rat

Energy Technology Data Exchange (ETDEWEB)

Daoo, J.V.; Suryawanshi, S.A. [Inst. of Science, Bombay (India)

1992-07-01

Effects of gamma irradiation (600 rads) on the ultrastructure of pancreatic islet, metabolism and some enzymes in wistar rat, are reported. Electron microscopic observations of endocrine pancreas revealed prominent changes in beta cells while alpha and delta cells were not much affected. Irradiation also inflicted hyperglycemia, increase in liver and muscle glycogen and decrease in insulin level. It has also increased the activity of enzymes but failed to produce significant changes in protein, lipid and mineral metabolism. (auth0008.

The enzymes of biotin dependent CO2 metabolism: What structures reveal about their reaction mechanisms

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Waldrop, Grover L; Holden, Hazel M; Maurice, Martin St

2012-01-01

Biotin is the major cofactor involved in carbon dioxide metabolism. Indeed, biotin-dependent enzymes are ubiquitous in nature and are involved in a myriad of metabolic processes including fatty acid synthesis and gluconeogenesis. The cofactor, itself, is composed of a ureido ring, a tetrahydrothiophene ring, and a valeric acid side chain. It is the ureido ring that functions as the CO2 carrier. A complete understanding of biotin-dependent enzymes is critically important for translational research in light of the fact that some of these enzymes serve as targets for anti-obesity agents, antibiotics, and herbicides. Prior to 1990, however, there was a dearth of information regarding the molecular architectures of biotin-dependent enzymes. In recent years there has been an explosion in the number of three-dimensional structures reported for these proteins. Here we review our current understanding of the structures and functions of biotin-dependent enzymes. In addition, we provide a critical analysis of what these structures have and have not revealed about biotin-dependent catalysis. PMID:22969052

The MetaCyc database of metabolic pathways and enzymes and the BioCyc collection of pathway/genome databases

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Caspi, Ron; Altman, Tomer; Dale, Joseph M.; Dreher, Kate; Fulcher, Carol A.; Gilham, Fred; Kaipa, Pallavi; Karthikeyan, Athikkattuvalasu S.; Kothari, Anamika; Krummenacker, Markus; Latendresse, Mario; Mueller, Lukas A.; Paley, Suzanne; Popescu, Liviu; Pujar, Anuradha; Shearer, Alexander G.; Zhang, Peifen; Karp, Peter D.

2010-01-01

The MetaCyc database (MetaCyc.org) is a comprehensive and freely accessible resource for metabolic pathways and enzymes from all domains of life. The pathways in MetaCyc are experimentally determined, small-molecule metabolic pathways and are curated from the primary scientific literature. With more than 1400 pathways, MetaCyc is the largest collection of metabolic pathways currently available. Pathways reactions are linked to one or more well-characterized enzymes, and both pathways and enzymes are annotated with reviews, evidence codes, and literature citations. BioCyc (BioCyc.org) is a collection of more than 500 organism-specific Pathway/Genome Databases (PGDBs). Each BioCyc PGDB contains the full genome and predicted metabolic network of one organism. The network, which is predicted by the Pathway Tools software using MetaCyc as a reference, consists of metabolites, enzymes, reactions and metabolic pathways. BioCyc PGDBs also contain additional features, such as predicted operons, transport systems, and pathway hole-fillers. The BioCyc Web site offers several tools for the analysis of the PGDBs, including Omics Viewers that enable visualization of omics datasets on two different genome-scale diagrams and tools for comparative analysis. The BioCyc PGDBs generated by SRI are offered for adoption by any party interested in curation of metabolic, regulatory, and genome-related information about an organism. PMID:19850718

Potential role of liver enzymes levels as predictor markers of glucose metabolism disorders in Tunisian population.

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Bouhajja, Houda; Abdelhedi, Rania; Amouri, Ali; Hadj Kacem, Faten; Marrakchi, Rim; Safi, Wajdi; Mrabet, Houcem; Chtourou, Lassaad; Charfi, Nadia; Fourati, Mouna; Bensassi, Salwa; Jamoussi, Kamel; Abid, Mohamed; Ayadi, Hammadi; Feki, Mouna Mnif; Elleuch, Noura Bougacha

2018-03-10

The relationship between liver enzymes and type 2 diabetes (T2D) risk is inconclusive. We aimed to evaluate the association between liver markers and risk of carbohydrate metabolism disorders and their discriminatory power for T2D prediction. This cross-sectional study enrolled 216 participants classified as normoglycemic, prediabetes, newly-diagnosed diabetes and diagnosed diabetes. All participants underwent anthropometric and biochemical measurements. The relationship between hepatic enzymes and glucose metabolism markers was evaluated by ANCOVA analyses. The associations between liver enzymes and incident carbohydrate metabolism disorders were analyzed through logistic regression and their discriminatory capacity for T2D by receiver operating characteristic (ROC) analysis. High alkaline phosphatase (AP), alanine aminotransferase (ALT), γ-glutamyltransferase (γGT) and aspartate aminotrasferase (AST) levels were independently related to decreased insulin sensitivity. Interestingly, higher AP level was significantly associated with increased risk of prediabetes (p=0.017), newly-diagnosed diabetes (p=0.004) and T2D (p=0.007). Elevated γGT level was an independent risk factor for T2D (p=0.032) and undiagnosed-T2D (p=0.010) in prediabetic and normoglycemic subjects, respectively. In ROC analysis, AP was a powerful predictor of incident diabetes and significantly improved T2D prediction. Liver enzymes within normal range, specifically AP levels, are associated with increased risk of carbohydrate metabolism disorders and significantly improved T2D prediction.

Characterisation of the cytochrome P450 enzymes involved in the in vitro metabolism of granisetron.

Science.gov (United States)

Bloomer, J C; Baldwin, S J; Smith, G J; Ayrton, A D; Clarke, S E; Chenery, R J

1994-01-01

1. The metabolism of granisetron was investigated in human liver microsomes to identify the specific forms of cytochrome P450 responsible. 2. 7-hydroxy and 9'-desmethyl granisetron were identified as the major products of metabolism following incubation of granisetron with human liver microsomes. At low, clinically relevant, concentrations of granisetron the 7-hydroxy metabolite predominated. Rates of granisetron 7-hydroxylation varied over 100-fold in the human livers investigated. 3. Enzyme kinetics demonstrated the involvement of at least two enzymes contributing to the 7-hydroxylation of granisetron, one of which was a high affinity component with a Km of 4 microM. A single, low affinity, enzyme was responsible for the 9'-desmethylation of granisetron. 4. Granisetron caused no inhibition of any of the cytochrome P450 activities investigated (CYP1A2, CYP2A6, CYP2B6, CYP2C9/8, CYP2C19, CYP2D6, CYP2E1 and CYP3A), at concentrations up to 250 microM. 5. Studies using chemical inhibitors selective for individual P450 enzymes indicated the involvement of cytochrome P450 3A (CYP3A), both pathways of granisetron metabolism being very sensitive to ketoconazole inhibition. Correlation data were consistent with the role of CYP3A3/4 in granisetron 9'-desmethylation but indicated that a different enzyme was involved in the 7-hydroxylation. PMID:7888294

Axonal and dendritic localization of mRNAs for glycogen-metabolizing enzymes in cultured rodent neurons.

Science.gov (United States)

Pfeiffer-Guglielmi, Brigitte; Dombert, Benjamin; Jablonka, Sibylle; Hausherr, Vanessa; van Thriel, Christoph; Schöbel, Nicole; Jansen, Ralf-Peter

2014-06-04

Localization of mRNAs encoding cytoskeletal or signaling proteins to neuronal processes is known to contribute to axon growth, synaptic differentiation and plasticity. In addition, a still increasing spectrum of mRNAs has been demonstrated to be localized under different conditions and developing stages thus reflecting a highly regulated mechanism and a role of mRNA localization in a broad range of cellular processes. Applying fluorescence in-situ-hybridization with specific riboprobes on cultured neurons and nervous tissue sections, we investigated whether the mRNAs for two metabolic enzymes, namely glycogen synthase (GS) and glycogen phosphorylase (GP), the key enzymes of glycogen metabolism, may also be targeted to neuronal processes. If it were so, this might contribute to clarify the so far enigmatic role of neuronal glycogen. We found that the mRNAs for both enzymes are localized to axonal and dendritic processes in cultured lumbar spinal motoneurons, but not in cultured trigeminal neurons. In cultured cortical neurons which do not store glycogen but nevertheless express glycogen synthase, the GS mRNA is also subject to axonal and dendritic localization. In spinal motoneurons and trigeminal neurons in situ, however, the mRNAs could only be demonstrated in the neuronal somata but not in the nerves. We could demonstrate that the mRNAs for major enzymes of neural energy metabolism can be localized to neuronal processes. The heterogeneous pattern of mRNA localization in different culture types and developmental stages stresses that mRNA localization is a versatile mechanism for the fine-tuning of cellular events. Our findings suggest that mRNA localization for enzymes of glycogen metabolism could allow adaptation to spatial and temporal energy demands in neuronal events like growth, repair and synaptic transmission.

Single nucleotide polymorphisms of the angiotensin-converting enzyme (ACE gene are associated with essential hypertension and increased ACE enzyme levels in Mexican individuals.

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Nancy Martínez-Rodríguez

Full Text Available AIM: To explore the role of the ACE gene polymorphisms in the risk of essential hypertension in Mexican Mestizo individuals and evaluate the correlation between these polymorphisms and the serum ACE levels. METHODS: Nine ACE gene polymorphisms were genotyped by 5' exonuclease TaqMan genotyping assays and polymerase chain reaction (PCR in 239 hypertensive and 371 non- hypertensive Mexican individuals. Haplotypes were constructed after linkage disequilibrium analysis. ACE serum levels were determined in selected individuals according to different haplotypes. RESULTS: Under a dominant model, rs4291 rs4335, rs4344, rs4353, rs4362, and rs4363 polymorphisms were associated with an increased risk of hypertension after adjusting for age, gender, BMI, triglycerides, alcohol consumption, and smoking. Five polymorphisms (rs4335, rs4344, rs4353, rs4362 and rs4363 were in strong linkage disequilibrium and were included in four haplotypes: H1 (AAGCA, H2 (GGATG, H3 (AGATG, and H4 (AGACA. Haplotype H1 was associated with decreased risk of hypertension, while haplotype H2 was associated with an increased risk of hypertension (OR = 0.77, P = 0.023 and OR = 1.41, P = 0.004 respectively. According to the codominant model, the H2/H2 and H1/H2 haplotype combinations were significantly associated with risk of hypertension after adjusted by age, gender, BMI, triglycerides, alcohol consumption, and smoking (OR = 2.0; P = 0.002 and OR = 2.09; P = 0.011, respectively. Significant elevations in serum ACE concentrations were found in individuals with the H2 haplotype (H2/H2 and H2/H1 as compared to H1/H1 individuals (P = 0.0048. CONCLUSION: The results suggest that single nucleotide polymorphisms and the "GGATG" haplotype of the ACE gene are associated with the development of hypertension and with increased ACE enzyme levels.

Determination of the activity signature of key carbohydrate metabolism enzymes in phenolic-rich grapevine tissues

DEFF Research Database (Denmark)

Covington, Elizabeth Dunn; Roitsch, Thomas Georg; Dermastia, Marina

2016-01-01

Physiological studies in plants often require enzyme extraction from tissues containing high concentrations of phenols and polyphenols. Unless removed or neutralized, such compounds may hinder extraction, inactivate enzymes, and interfere with enzyme detection. The following protocol for activity...... assays for enzymes of primary carbohydrate metabolism, while based on our recently published one for quantitative measurement of activities using coupled spectrophotometric assays in a 96-well format, is tailored to the complexities of phenolic- and anthocyanin-rich extracts from grapevine leaf...

Glutamate and GABA-metabolizing enzymes in post-mortem cerebellum in Alzheimer's disease: phosphate-activated glutaminase and glutamic acid decarboxylase.

Science.gov (United States)

Burbaeva, G Sh; Boksha, I S; Tereshkina, E B; Savushkina, O K; Prokhorova, T A; Vorobyeva, E A

2014-10-01

Enzymes of glutamate and GABA metabolism in postmortem cerebellum from patients with Alzheimer's disease (AD) have not been comprehensively studied. The present work reports results of original comparative study on levels of phosphate-activated glutaminase (PAG) and glutamic acid decarboxylase isoenzymes (GAD65/67) in autopsied cerebellum samples from AD patients and matched controls (13 cases in each group) as well as summarizes published evidence for altered levels of PAG and GAD65/67 in AD brain. Altered (decreased) levels of these enzymes and changes in links between amounts of these enzymes and other glutamate-metabolizing enzymes (such as glutamate dehydrogenase and glutamine synthetase-like protein) in AD cerebella suggest significantly impaired glutamate and GABA metabolism in this brain region, which was previously regarded as not substantially involved in AD pathogenesis.

Partial digestion with restriction enzymes of ultraviolet-irradiated human genomic DNA: a method for identifying restriction site polymorphisms

International Nuclear Information System (INIS)

Nobile, C.; Romeo, G.

1988-01-01

A method for partial digestion of total human DNA with restriction enzymes has been developed on the basis of a principle already utilized by P.A. Whittaker and E. Southern for the analysis of phage lambda recombinants. Total human DNA irradiated with uv light of 254 nm is partially digested by restriction enzymes that recognize sequences containing adjacent thymidines because of TT dimer formation. The products resulting from partial digestion of specific genomic regions are detected in Southern blots by genomic-unique DNA probes with high reproducibility. This procedure is rapid and simple to perform because the same conditions of uv irradiation are used for different enzymes and probes. It is shown that restriction site polymorphisms occurring in the genomic regions analyzed are recognized by the allelic partial digest patterns they determine

Association Study between Ghrelin Gene Polymorphism and Metabolic Syndrome in a Han Chinese Population.

Science.gov (United States)

You, Yueyue; Yu, Yaqin; Wu, Yanhua; Rao, Wenwang; Zhang, Yangyu; Liu, Yingyu; Yang, Guang; Fu, Yingli; Shi, Jieping; Kou, Changgui

2017-01-01

Ghrelin, in humans, is a hormone secreted from the stomach with an orexigenic effect, which is good for digestion and absorption, as well as regulating physical growth, metabolism, and energy balance. It is also involved in the development of metabolic syndrome (MetS) and type 2 diabetes mellitus (T2DM). This study assessed the association between single nucleotide variants of the GHRL gene and the risk of metabolic syndrome in a Han Chinese population. A case-control study was performed on 3780 Han Chinese comprising 1813 MetS cases and 1967 controls. Three missense polymorphisms in GHRL (rs26802, rs10490816, and rs696217) were selected, and the association between these polymorphisms and the risk of MetS was investigated. Metabolic syndrome was defined according to the criteria of the International Diabetes Federation (IDF). Using Pearson's 2 test, we found that there were no significant differences in genotype distributions and allele frequencies between cases and controls (all p > 0.05). There were also no significant differences in haplotype distributions between MetS cases and healthy controls. Furthermore, we confirmed that rs26802 of the GHRL gene is associated with body mass index (BMI), waist circumference, systolic blood pressure (SBP), and fasting glucose; rs10490816 is associated with triglycerides (TG) and total cholesterol (TC); while rs696217 is associated with hip circumference and fasting glucose. We concluded that mutations in the GHRL gene did not confer risk for MetS in our study population. Therefore, functional analysis and replication studies in other populations are needed to further investigate the exact role of the GHRL gene in MetS.

[Important application of intestinal transporters and metabolism enzymes on gastrointestinal disposal of active ingredients of Chinese materia medica].

Science.gov (United States)

Bi, Xiaolin; Du, Qiu; Di, Liuqing

2010-02-01

Oral drug bioavailability depends on gastrointestinal absorption, intestinal transporters and metabolism enzymes are the important factors in drug gastrointestinal absorption and they can also be induced or inhibited by the active ingredients of Chinese materia medica. This article presents important application of intestinal transporters and metabolism enzymes on gastrointestinal disposal of the active ingredients of Chinese materia medica, and points out the importance of research on transport and metabolism of the active ingredients of Chinese materia medica in Chinese extract and Chinese medicinal formulae.

Dose-response effects of lycopene on selected drug-metabolizing and antioxidant enzymes in the rat

DEFF Research Database (Denmark)

Breinholt, V.; Lauridsen, S. T.; Daneshvar, B.

2000-01-01

to be affected by prior. lycopene exposure. The level of PhIP-DNA adducts in the liver or colon was likewise not affected by lycopene at any dose. Overall, the present study provides evidence that lycopene administered in the diet of young female rats exerts minor modifying effects toward antioxidant and drug......-metabolizing enzymes involved in the protection against oxidative stress and cancer. The fact that these enzymatic activities are induced at all of these very low plasma levels, could be taken to suggest that modulation of antioxidant and drug-metabolizing enzymes map indeed be relevant to humans, which in general...

Alcohol dehydrogenase and aldehyde dehydrogenase gene polymorphisms, alcohol intake and the risk of colorectal cancer in the European Prospective Investigation into Cancer and Nutrition study

DEFF Research Database (Denmark)

Ferrari, P.; McKay, J. D.; Jenab, M.

2012-01-01

BACKGROUND/OBJECTIVES: Heavy alcohol drinking is a risk factor of colorectal cancer (CRC), but little is known on the effect of polymorphisms in the alcohol-metabolizing enzymes, alcohol dehydrogenase (ADH) and aldehyde dehydrogenase (ALDH) on the alcohol-related risk of CRC in Caucasian populati...

Metabolic Polymorphisms and Clinical Findings Related to Benzene Poisoning Detected in Exposed Brazilian Gas-Station Workers

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Simone Mitri

2015-07-01

Full Text Available Benzene is a ubiquitous environmental pollutant and an important industrial chemical present in both gasoline and motor vehicle emissions. Occupational human exposure to benzene occurs in the petrochemical and petroleum refining industries as well as in gas-station workers, where it can lead to benzene poisoning (BP, but the mechanisms of BP are not completely understood. In Brazil, a significant number of gas-station service workers are employed. The aim of the present study was to evaluate alterations related to BP and metabolic polymorphisms in gas-station service workers exposed to benzene in the city of Rio de Janeiro, Brazil. Occupational exposure was based on clinical findings related to BP, and metabolic polymorphisms in 114 Brazilian gas-station attendants. These workers were divided into No Clinical Findings (NCF and Clinical Findings (CF groups. Neutrophil and Mean Corpuscular Volume (MCV showed a significant difference between the two study groups, and neutrophil has the greatest impact on the alterations suggestive of BP. The clinical findings revealed higher frequencies of symptoms in the CF group, although not all members presented statistical significance. The frequencies of alleles related to risk were higher in the CF group for GSTM1, GSTT1, CYP2E1 7632T > A, but lower for NQO1 and CYP2E1 1053C > T genotypes. Moreover, an association was found between GSTM1 null and alterations related to BP, but we did not observe any effects of other polymorphisms. Variations in benzene metabolizing genes may modify benzene toxicity and should be taken into consideration during risk assessment evaluations.

Insertion/deletion polymorphism of the angiotensin-converting enzyme gene and the risk of hypertension among residents of two cities, South-South Nigeria

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Mary Esien Kooffreh

2014-01-01

Conclusion: The I/D polymorphism of the angiotensin-converting enzyme gene was a risk factor for hypertension in the sample population of Calabar and Uyo. This research will form baseline information for subsequent molecular studies in this population.

Alginate Immobilization of Metabolic Enzymes (AIME) for High-Throughput Screening Assays (SOT)

Science.gov (United States)

Alginate Immobilization of Metabolic Enzymes (AIME) for High-Throughput Screening Assays DE DeGroot, RS Thomas, and SO SimmonsNational Center for Computational Toxicology, US EPA, Research Triangle Park, NC USAThe EPA’s ToxCast program utilizes a wide variety of high-throughput s...

Polymorphism of the renalase gene in gestational diabetes mellitus.

Science.gov (United States)

Fatima, Syeda Sadia; Jamil, Zehra; Alam, Faiza; Malik, Hajira Zafar; Madhani, Sarosh Irfan; Ahmad, Muhammad Saad; Shabbir, Tayyab; Rehmani, Muhammed Noman; Rabbani, Amna

2017-01-01

Renalase is considered as a novel candidate gene for type 2 diabetes. In this study, we aimed to investigate the relationship of serum renalase and two single nucleotide polymorphisms with gestational diabetes mellitus. One hundred and ninety-eight normotensive pregnant females (n = 99 gestational diabetes mellitus; n = 99 euglycemic pregnant controls) were classified according to the International Association of the Diabetes and Pregnancy Study criteria. Fasting and 2-h post glucose load blood levels and anthropometric assessment was performed. Serum renalase was measured using enzyme-linked immunosorbent assay, whereas DNA samples were genotyped for renalase single nucleotide polymorphisms rs2576178 and rs10887800 using Polymerase chain reaction-Restriction fragment length polymorphism method. In an age-matched case control study, no difference was observed in the serum levels of renalase (p > 0.05). The variant rs10887800 showed an association with gestational diabetes mellitus and remained significant after multiple adjustments (p gestational diabetes. Although gestational diabetes mellitus is self-reversible, yet presence of this minor G allele might predispose to metabolic syndrome phenotypes in near the future.

Vitamin D receptor and vitamin D metabolizing enzymes are expressed in the human male reproductive tract

DEFF Research Database (Denmark)

Blomberg Jensen, Martin; Nielsen, John E; Jørgensen, Anne

2010-01-01

, since it is not solely dependent on VDR expression, but also on cellular uptake of circulating VD and presence and activity of VD metabolizing enzymes. Expression of VD metabolizing enzymes has not previously been investigated in human testis and male reproductive tract. Therefore, we performed......The vitamin D receptor (VDR) is expressed in human testis, and vitamin D (VD) has been suggested to affect survival and function of mature spermatozoa. Indeed, VDR knockout mice and VD deficient rats show decreased sperm counts and low fertility. However, the cellular response to VD is complex...

Metabolic enzyme activities of abyssal and hadal fishes: pressure effects and a re-evaluation of depth-related changes

Science.gov (United States)

Gerringer, M. E.; Drazen, J. C.; Yancey, P. H.

2017-07-01

Metabolic enzyme activities of muscle tissue have been useful and widely-applied indicators of whole animal metabolic capacity, particularly in inaccessible systems such as the deep sea. Previous studies have been conducted at atmospheric pressure, regardless of organism habitat depth. However, maximum reaction rates of some of these enzymes are pressure dependent, complicating the use of metabolic enzyme activities as proxies of metabolic rates. Here, we show pressure-related rate changes in lactate and malate dehydrogenase (LDH, MDH) and pyruvate kinase (PK) in six fish species (2 hadal, 2 abyssal, 2 shallow). LDH maximal reaction rates decreased with pressure for the two shallow species, but, in contrast to previous findings, it increased for the four deep species, suggesting evolutionary changes in LDH reaction volumes. MDH maximal reaction rates increased with pressure in all species (up to 51±10% at 60 MPa), including the tide pool snailfish, Liparis florae (activity increase at 60 MPa 44±9%), suggesting an inherent negative volume change of the reaction. PK was inhibited by pressure in all species tested, including the hadal liparids (up to 34±3% at 60 MPa), suggesting a positive volume change during the reaction. The addition of 400 mM TMAO counteracted this inhibition at both 0.5 and 2.0 mM ADP concentrations for the hadal liparid, Notoliparis kermadecensis. We revisit depth-related trends in metabolic enzyme activities according to these pressure-related rate changes and new data from seven abyssal and hadal species from the Kermadec and Mariana trenches. Results show that, with abyssal and hadal species, pressure-related rate changes are another variable to be considered in the use of enzyme activities as proxies for metabolic rate, in addition to factors such as temperature and body mass. Intraspecific increases in tricarboxylic acid cycle enzymes with depth of capture, independent of body mass, in two hadal snailfishes suggest improved nutritional

Variation in antiviral 2',5'-oligoadenylate synthetase (2'5'AS) enzyme activity is controlled by a single-nucleotide polymorphism at a splice-acceptor site in the OAS1 gene

DEFF Research Database (Denmark)

Bonnevie-Nielsen, Vagn; Field, L Leigh; Lu, Shao

2005-01-01

It is likely that human genetic differences mediate susceptibility to viral infection and virus-triggered disorders. OAS genes encoding the antiviral enzyme 2',5'-oligoadenylate synthetase (2'5'AS) are critical components of the innate immune response to viruses. This enzyme uses adenosine......=.0044), but not spousal pairs, suggesting strong genetic control of basal activity. We next analyzed association between basal activity and 15 markers across the OAS gene cluster. Significant association was detected at multiple markers, the strongest being at an A/G single-nucleotide polymorphism...... at the exon 7 splice-acceptor site (AG or AA) of the OAS1 gene. At this unusual polymorphism, allele G had a higher gene frequency in persons with high enzyme activity than in those with low enzyme activity (0.44 vs. 0.20; P=3 x 10(-11)). Enzyme activity varied in a dose-dependent manner across the GG, GA...

Activities of xenobiotic metabolizing enzymes in rat placenta and liver in vitro

NARCIS (Netherlands)

Fabian, Eric; Wang, Xinyi; Engel, Franziska; Li, Hequn; Landsiedel, Robert; Ravenzwaay, van Bennard

2016-01-01

In order to assess whether the placental metabolism of xenobiotic compounds should be taken into consideration for physiologically-based toxicokinetic (PBTK) modelling, the activities of seven phase I and phase II enzymes have been quantified in the 18-day placenta of untreated Wistar rats. To

Association between angiotensin II receptor gene polymorphism and serum angiotensin converting enzyme (SACE) activity in patients with sarcoidosis.

Science.gov (United States)

Takemoto, Y; Sakatani, M; Takami, S; Tachibana, T; Higaki, J; Ogihara, T; Miki, T; Katsuya, T; Tsuchiyama, T; Yoshida, A; Yu, H; Tanio, Y; Ueda, E

1998-06-01

Serum angiotensin converting enzyme (SACE) is considered to reflect disease activity in sarcoidosis. SACE activity is increased in many patients with active sarcoid lesions. The mechanism for the increased SACE activity in this disease has not been clarified. ACE insertion/deletion (I/D) gene polymorphism has been reported to have an association with SACE levels in sarcoidosis, but no evidence of an association between angiotensin II receptor gene polymorphism and SACE in this disease has been found. A study of the association of angiotensin II receptor gene polymorphisms with sarcoidosis was therefore undertaken. ACE (I/D), angiotensin II type 1 receptor (AGTR1), and angiotensin II type 2 receptor (AGTR2) gene polymorphisms were investigated by polymerase chain reaction (PCR) and SACE levels were measured in three groups of patients: those with sarcoidosis or tuberculosis and normal controls. There was no difference in allele frequency of AGTR1 and AGTR2 polymorphism among the three groups. Neither AGTR1 nor AGTR2 polymorphisms were associated with sarcoidosis. SACE activity was higher in patients with sarcoidosis with the AGTR1 A/C genotype than in others. However, this tendency was not detected in patients with tuberculosis. The AGTR1 allele C is associated with high activity of SACE in patients with sarcoidosis. It is another predisposing factor for high levels of SACE in patients with sarcoidosis and is considered to be an independent factor from the ACE D allele for high levels of SACE in sarcoidosis. This fact could be one of the explanations for the increased SACE activity in sarcoidosis.

CYP2D6 polymorphisms and their influence on risperidone treatment

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Puangpetch A

2016-12-01

Full Text Available Apichaya Puangpetch,1 Natchaya Vanwong,1 Nopphadol Nuntamool,2 Yaowaluck Hongkaew,1 Monpat Chamnanphon,1 Chonlaphat Sukasem1 1Division of Pharmacogenomics and Personalized Medicine, Department of Pathology, Faculty of Medicine Ramathibodi Hospital, 2Molecular Medicine, Faculty of Science, Mahidol University, Bangkok, Thailand Abstract: Cytochrome P450 enzyme especially CYP2D6 plays a major role in biotransformation. The interindividual variations of treatment response and toxicity are influenced by the polymorphisms of this enzyme. This review emphasizes the effect of CYP2D6 polymorphisms in risperidone treatment in terms of basic knowledge, pharmacogenetics, effectiveness, adverse events, and clinical practice. Although the previous studies showed different results, the effective responses in risperidone treatment depend on the CYP2D6 polymorphisms. Several studies suggested that CYP2D6 polymorphisms were associated with plasma concentration of risperidone, 9-hydroxyrisperidone, and active moiety but did not impact on clinical outcomes. In addition, CYP2D6 poor metabolizer showed more serious adverse events such as weight gain and prolactin than other predicted phenotype groups. The knowledge of pharmacogenomics of CYP2D6 in risperidone treatment is increasing, and it can be used for the development of personalized medication in term of genetic-based dose recommendation. Moreover, the effects of many factors in risperidone treatment are still being investigated. Both the CYP2D6 genotyping and therapeutic drug monitoring are the important steps to complement the genetic-based risperidone treatment. Keywords: CYP2D6, risperidone, polymorphisms, adverse drug reaction, pharmacogenetics, pharmacokinetics, pharmacodynamics

The aldehyde dehydrogenase 2 polymorphisms on neuropsychological performance in bipolar II disorder with or without comorbid anxiety disorder.

Science.gov (United States)

Lu, Ru-Band; Chang, Yun-Hsuan; Wang, Tzu-Yun; Lee, Sheng-Yu; Chen, Po See; Yang, Yen Kuang

2018-01-01

Anxiety disorders (ADs), the most common comorbid illnesses with bipolar disorder (BP) has been reported to associate with dopamine system. Dopamine, metabolized to 3,4-dihydroxyphenylacetic acid (DOPAC) by aldehyde dehydrogenase 2 (ALDH2), and the distribution of the ALDH2*1/*1, and ALDH2*1/*2+ALDH*2/*2 alleles in the Han Chinese general population is relatively equal. The association between dopamine metabolic enzymes and cognitive performance in patients with bipolar II disorder (BP-II) comorbid with AD is unclear. This study proposed to explore the role of ALDH2 polymorphisms on neuropsychological performance between BP-II comorbid with or without AD. One hundred ninety-seven BP-II patients with and without a comorbid AD were recruited and compared with 130 healthy controls (HCs). A polymerase chain reaction and a restriction fragment length polymorphism analysis were used to determine genotypes for ALDH2, and study participants underwent neuropsychological tests. An interaction between AD comorbidity and the ALDH2 polymorphisms was found in different domain of cognitive dysfunction in the BP-II patients. The ALDH2 polymorphisms might have different effects on the neuropsychological performance of BP-II patients with and without comorbid AD.

Characterization of Sugar Contents and Sucrose Metabolizing Enzymes in Developing Leaves of Hevea brasiliensis

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Jinheng Zhu

2018-02-01

Full Text Available Sucrose-metabolizing enzymes in plant leaves have hitherto been investigated mainly in temperate plants, and rarely conducted in tandem with gene expression and sugar analysis. Here, we investigated the sugar content, gene expression, and the activity of sucrose-metabolizing enzymes in the leaves of Hevea brasiliensis, a tropical tree widely cultivated for natural rubber. Sucrose, fructose and glucose were the major sugars detected in Hevea leaves at four developmental stages (I to IV, with starch and quebrachitol as minor saccharides. Fructose and glucose contents increased until stage III, but decreased strongly at stage IV (mature leaves. On the other hand, sucrose increased continuously throughout leaf development. Activities of all sucrose-cleaving enzymes decreased markedly at maturation, consistent with transcript decline for most of their encoding genes. Activity of sucrose phosphate synthase (SPS was low in spite of its high transcript levels at maturation. Hence, the high sucrose content in mature leaves was not due to increased sucrose-synthesizing activity, but more to the decline in sucrose cleavage. Gene expression and activities of sucrose-metabolizing enzymes in Hevea leaves showed striking differences compared with other plants. Unlike in most other species where vacuolar invertase predominates in sucrose cleavage in developing leaves, cytoplasmic invertase and sucrose synthase (cleavage direction also featured prominently in Hevea. Whereas SPS is normally responsible for sucrose synthesis in plant leaves, sucrose synthase (synthesis direction was comparable or higher than that of SPS in Hevea leaves. Mature Hevea leaves had an unusually high sucrose:starch ratio of about 11, the highest reported to date in plants.

Assembly and multiple gene expression of thermophilic enzymes in Escherichia coli for in vitro metabolic engineering.

Science.gov (United States)

Ninh, Pham Huynh; Honda, Kohsuke; Sakai, Takaaki; Okano, Kenji; Ohtake, Hisao

2015-01-01

In vitro reconstitution of an artificial metabolic pathway is an emerging approach for the biocatalytic production of industrial chemicals. However, several enzymes have to be separately prepared (and purified) for the construction of an in vitro metabolic pathway, thereby limiting the practical applicability of this approach. In this study, genes encoding the nine thermophilic enzymes involved in a non-ATP-forming chimeric glycolytic pathway were assembled in an artificial operon and co-expressed in a single recombinant Escherichia coli strain. Gene expression levels of the thermophilic enzymes were controlled by their sequential order in the artificial operon. The specific activities of the recombinant enzymes in the cell-free extract of the multiple-gene-expression E. coli were 5.0-1,370 times higher than those in an enzyme cocktail prepared from a mixture of single-gene-expression strains, in each of which a single one of the nine thermophilic enzymes was overproduced. Heat treatment of a crude extract of the multiple-gene-expression cells led to the denaturation of indigenous proteins and one-step preparation of an in vitro synthetic pathway comprising only a limited number of thermotolerant enzymes. Coupling this in vitro pathway with other thermophilic enzymes including the H2 O-forming NADH oxidase or the malate/lactate dehydrogenase facilitated one-pot conversion of glucose to pyruvate or lactate, respectively. © 2014 Wiley Periodicals, Inc.

Elevated urinary albumin excretion is not linked to the angiotensin I-converting enzyme gene polymorphism in clinically healthy subjects

DEFF Research Database (Denmark)

Clausen, P; Jensen, J S; Borch-Johnsen, K

2000-01-01

An elevated urinary albumin excretion (UAE) in non-diabetic subjects without renal or cardiovascular disease has been shown to be predictive of ischaemic heart disease. An insertion (I)/deletion (D) polymorphism in the angiotensin I-converting enzyme (ACE) gene has been identified and the D allele...... control group (n = 46). Elevated UAE in clinically healthy subjects is not linked to the ACE gene polymorphism....... aged 40-65 years with elevated UAE in a dipstick negative urinary sample (n = 27) from The Copenhagen City Heart Study. Neither the ACE genotype distribution (p = 0.12) nor the D and I allele frequencies (p = 0.69) differed significantly between subjects with elevated UAE and a matched normoalbuminuric...

A Meta-analysis on the correlation between the polymorphism of angiotensin converting enzyme gene and hypertrophic cardiomyopathy

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Ling CHEN

2014-01-01

Full Text Available Objective　To systematically investigate the correlation between the polymorphism of angiotensin converting enzyme (ACE gene I/D and hypertrophic cardiomyopathy. Methods　The databases, such as PubMed, Embase, OVID, Web of Science, Cochrane library, CNKI, WanFang Data and VIP, were searched to collect the studies on the correlation between ACE I/D polymorphism and hypertrophic cardiomyopathy susceptibility. Studies that met the inclusion criteria were Meta-analyzed using Stata 11.0 software. Results　Fifteen articles were collected including 1114 cases and 1648 controls. The Meta-analysis indicated that there was significant correlation between the 4 models of ACE I/D polymorphism and hypertrophic cardiomyopathy susceptibility [D vs I: OR=1.49, 95%CI (1.20, 1.84; DD vs (ID+II: OR=1.56, 95%CI (1.17, 2.08; (DD+ID vs II: OR=1.76, 95%CI (1.30, 2.38; DD vs II: OR=2.20, 95%CI (1.44, 3.37]. In subgroup analysis, the significant difference existed in Asian population, but no significance was found in European population (P<0.05. Conclusions　There is a positive correlation between hypertrophic cardiomyopathy and ACE I/D polymorphism in population, and D allele and DD genotype are likely to be the risk factors of hypertrophic cardiomyopathy. But such correlation does not exist in European population. DOI: 10.11855/j.issn.0577-7402.2013.12.07

Leptin receptor and ghrelin genes polymorphisms in relation to the metabolism of lipids

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Anna Trakovická

2015-10-01

Full Text Available The aim of this work was to analyse genetic polymorphisms in genes encoding leptin receptor (LEPR and ghrelin (GHR as genetic markers of metabolic disorders in human nutrition. Genomic DNA was obtained from in total 84 human blood samples. Effect of analysed genetic markers was evaluated for three biochemical parameters: total cholesterol, HDL and LDL cholesterol. The PCR-RFLP method was used for identification of SNPs in LEPR (Gln223Arg and GHR (171T/C genes. In analysed population prevalence of heterozygous LEPRAG (47.62% and GHRCT (40.48% genotypes was observed. Frequency of LEPRA and LEPRB alleles were 0.55 and 0.45, respectively. Similar the GHRC allele had only slight predominance than GHRT allele (0.54/0.46. In population was found higher level of observed heterozygosity across loci (0.44. For both SNPs was found high effective allele number (1.98 which was also transferred to the median level of polymorphic information content (0.37. Association analysis of LEPR and GHR genotypes effect on selected biochemical parameters was performed using GLM procedure. Significant association was found only for levels of LDL cholesterol (P<0.01. Our study shows that both genes are involved in nutritional status and therefore can be considered as candidate genes of lipids metabolism disorders and obesity.

Insertion/deletion polymorphism in the angiotensin-I-converting enzyme gene is associated with coronary heart disease in IDDM patients with diabetic nephropathy

DEFF Research Database (Denmark)

Tarnow, L; Cambien, Francois; Rossing, P

1995-01-01

Insulin-dependent diabetic (IDDM) patients with diabetic nephropathy have a highly increased morbidity and mortality from coronary heart disease. An insertion (I) /deletion (D) polymorphism in the angiotensin-I-converting enzyme (ACE) gene has been shown to be associated with coronary heart disea...

Detection of the Single Nucleotide Polymorphism at Position rs2735940 in the Human Telomerase Reverse Transcriptase Gene by the Introduction of a New Restriction Enzyme Site for the PCR-RFLP Assay.

Science.gov (United States)

Wang, Sihua; Ding, Mingcui; Duan, Xiaoran; Wang, Tuanwei; Feng, Xiaolei; Wang, Pengpeng; Yao, Wu; Wu, Yongjun; Yan, Zhen; Feng, Feifei; Yu, Songcheng; Wang, Wei

2017-09-01

It has been shown that the single nucleotide polymorphism (SNP) of the rs2735940 site in the human telomerase reverse transcriptase ( hTERT ) gene is associated with increased cancer risk. The traditional method to detect SNP genotypes is polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). However, there is a limitation to utilizing PCR-RFLP due to a lack of proper restriction enzyme sites at many polymorphic loci. This study used an improved PCR-RFLP method with a mismatched base for detection of the SNP rs2735940. A new restriction enzyme cutting site was created by created restriction site PCR (CRS-PCR), and in addition, the restriction enzyme Msp I for CRS-PCR was cheaper than other enzymes. We used this novel assay to determine the allele frequencies in 552 healthy Chinese Han individuals, and found the allele frequencies to be 63% for allele C and 37% for allele T In summary, the modified PCR-RFLP can be used to detect the SNP of rs2735940 with low cost and high efficiency. © 2017 by the Association of Clinical Scientists, Inc.

[Correlation of angiotensin-converting enzyme 2 gene polymorphism with antihypertensive effects of benazepril].

Science.gov (United States)

Chen, Qing; Tang, Xun; Yu, Can-qing; Chen, Da-fang; Tian, Jun; Cao, Yang; Fan, Wen-yi; Cao, Wei-hua; Zhan, Si-yan; Lv, Jun; Guo, Xiao-xia; Li, Li-ming; Hu, Yong-hua

2010-06-18

To explore the correlation of rs2106809 from angiotensin-converting enzyme 2 gene with antihypertensive effects of benazepril, as well as its interactions with polymorphisms of angiotensinogen(AGT) and angiotensin II type 1 receptor(AGTR1) gene. Correlation between rs2106809 and blood pressure reduction was estimated based on a field trail with 1 831 hypertensive patients using benazepril for 2 weeks. Generalized multifactor dimensionality reduction (GMDR) was used to explore the interactions of rs2106809 and 8 single nucleotide polymorphisms (SNPs) of AGTR1 gene and 3 SNPs of AGT gene. rs2106809 was found to be associated with reduction in systolic blood pressure and pulse pressure in women, as well as pulse pressure reduction in men. T allele carriers presented more blood pressure reduction (1.4, 1.3 and 0.9 mmHg/T allele respectively). Gene-gene interactions involving rs2106809 were found in systolic blood pressure reduction of men, and the response to benazepril of non-sensitive genotypes carriers was 8.2 (95% confidence interval: 6.6-9.7) mmHg, lower than that of sensitive genotypes carriers. rs2106809 might act as an independent influencing factor or component of gene-gene interaction in blood pressure reducing effects of benazepril.

Effect of UGT2B7*2 and CYP2C8*4 polymorphisms on diclofenac metabolism.

Science.gov (United States)

Lazarska, Katarzyna E; Dekker, Stefan J; Vermeulen, Nico P E; Commandeur, Jan N M

2018-03-01

The use of diclofenac is associated with rare but severe drug-induced liver injury (DILI) in a very small number of patients. The factors which predispose susceptible patients to hepatotoxicity of diclofenac are still incompletely understood. Formation of protein-reactive metabolites by UDP-glucuronosyl transferases and cytochromes P450 is commonly considered to play an important role, as indicated by the detection of covalent protein adducts and antibodies in the serum of patients suffering from diclofenac-induced liver injury. Since no associations have been found with HLA-alleles, polymorphisms of genes encoding for proteins involved in the disposition of diclofenac may be important. Previous association studies showed that possession of the UGT2B7*2 and CYP2C8*4 alleles is more common in cases of diclofenac-induced DILI. In the present study, the metabolism of diclofenac by UGT2B7*2 and CYP2C8*4 was compared with their corresponding wild-type enzymes. Enzyme kinetic analysis revealed that recombinant UGT2B7*2 showed an almost 6-fold lower intrinsic clearance of diclofenac glucuronidation compared to UGT2B7*1. The mutant CYP2C8*4 showed approximately 35% reduced activity in the 4'-hydroxylation of diclofenac acyl glucuronide. Therefore, a decreased hepatic exposure to diclofenac acyl glucuronide is expected in patients with the UGT2B7*2 genotype. The increased risk for hepatotoxicity, therefore, might be the result from a shift to oxidative bioactivation to cytotoxic quinoneimines. Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.

Tools and strategies for discovering novel enzymes and metabolic pathways

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John A. Gerlt

2016-12-01

Full Text Available The number of entries in the sequence databases continues to increase exponentially – the UniProt database is increasing with a doubling time of ∼4 years (2% increase/month. Approximately 50% of the entries have uncertain, unknown, or incorrect function annotations because these are made by automated methods based on sequence homology. If the potential in complete genome sequences is to be realized, strategies and tools must be developed to facilitate experimental assignment of functions to uncharacterized proteins discovered in genome projects. The Enzyme Function Initiative (EFI; previously supported by U54GM093342 from the National Institutes of Health, now supported by P01GM118303 developed web tools for visualizing and analyzing (1 sequence and function space in protein families (EFI-EST and (2 genome neighbourhoods in microbial and fungal genomes (EFI-GNT to assist the design of experimental strategies for discovering the in vitro activities and in vivo metabolic functions of uncharacterized enzymes. The EFI developed an experimental platform for large-scale production of the solute binding proteins (SBPs for ABC, TRAP, and TCT transport systems and their screening with a physical ligand library to identify the identities of the ligands for these transport systems. Because the genes that encode transport systems are often co-located with the genes that encode the catabolic pathways for the transported solutes, the identity of the SBP ligand together with the EFI-EST and EFI-GNT web tools can be used to discover new enzyme functions and new metabolic pathways. This approach is demonstrated with the characterization of a novel pathway for ethanolamine catabolism.

Angiotensin-converting enzyme insertion/deletion polymorphism ...

African Journals Online (AJOL)

The clinical manifestations of KD include per- sistent fever, non-purulent conjunctivitis, diffuse muco- sal inflammation, polymorphous skin rashes, indurative angioedema of the hands and feet, and non-suppurative cervical lymphadenopathy3. In about 20% of patients vasculitis will lead to coronary artery lesions as detect-.

The Impact of Drug Metabolism Gene Polymorphisms on Therapeutic Response and Survival in Diffuse Large B-Cell Lymphoma Patients.

Science.gov (United States)

Pál, Ildikó; Illés, Árpád; Gergely, Lajos; Pál, Tibor; Radnay, Zita; Szekanecz, Zoltán; Zilahi, Erika; Váróczy, László

2018-04-01

Diffuse large B-cell lymphoma (DLBCL) accounts for 30% of all non-Hodgkin lymphomas (NHL) and 80% of agressive lymphomas. Besides the traditional International Prognostic Index (IPI), some other factors may also influence the prognosis of DLBCL patients. To study how the genetic polymorphisms in the metabolic pathway influence the event-free and overall survivals and therapeutic responses in DLBCL. The study was comprised of 51 patients (32 men, 19 women). The average age was 53.1 years. DLBCL was diagnosed between 2011 and 2016 and the average follow-up time was 3.78 years. These patients received 1-8 cycles (an average of 6.2 cycles) of rituximab, cyclophosphamide, doxorubicin, vincristin, prednisolon (R-CHOP) immunochemotherapy. Real-time polymerase chain reaction was used to determine the genetic polymorphisms of CYP2E1, GSTP1, NAT1, and NAT2 genes. Our results showed that the polymorphisms of CYP2E1, GSTP1, and NAT1 genes did not influence the prognosis of DLBCL patients significantly. In terms of the NAT2 gene, GG homozygous patients showed slightly better therapeutic response and survival results compared to those bearing an A allele; however, the differences were not statistically significant. Our results could not confirm that genetic polymorphism in metabolic pathways has any predictive role in DLBCL.

A comparative study on the metabolism of Epimedium koreanum Nakai-prenylated flavonoids in rats by an intestinal enzyme (lactase phlorizin hydrolase) and intestinal flora.

Science.gov (United States)

Zhou, Jing; Chen, Yan; Wang, Ying; Gao, Xia; Qu, Ding; Liu, Congyan

2013-12-24

The aim of this study was to compare the significance of the intestinal hydrolysis of prenylated flavonoids in Herba Epimedii by an intestinal enzyme and flora. Flavonoids were incubated at 37 °C with rat intestinal enzyme and intestinal flora. HPLC-UV was used to calculate the metabolic rates of the parent drug in the incubation and LC/MS/MS was used to determine the chemical structures of metabolites generated by different flavonoid glycosides. Rates of flavonoid metabolism by rat intestinal enzyme were quicker than those of intestinal flora. The sequence of intestinal flora metabolic rates was icariin>epimedin B>epimedin A>epimedin C>baohuoside I, whereas the order of intestinal enzyme metabolic rates was icariin>epimedin A>epimedin C>epimedin B>baohuoside I. Meanwhile, the LC/MS/MS graphs showed that icariin produced three products, epimedin A/B/C had four and baohuoside I yielded one product in incubations of both intestinal enzyme and flora, which were more than the results of HPLC-UV due to the fact LC/MS/MS has lower detectability and higher sensitivity. Moreover, the outcomes indicated that the rate of metabolization of flavonoids by intestinal enzyme were faster than those of intestinal flora, which was consistent with the HPLC-UV results. In conclusion, the metabolic pathways of the same components by intestinal flora and enzyme were the same. What's more, an intestinal enzyme such as lactase phlorizin hydrolase exhibited a more significant metabolic role in prenylated flavonoids of Herba Epimedi compared with intestinal flora.

Genetic polymorphisms and possible gene-gene interactions in metabolic and DNA repair genes: Effects on DNA damage

Czech Academy of Sciences Publication Activity Database

Naccarati, Alessio; Souček, P.; Štětina, R.; Haufroid, V.; Kumar, R.; Vodičková, Ludmila; Trtková, K.; Dušinská, M.; Hemminki, K.; Vodička, Pavel

2006-01-01

Roč. 593, 1-2 (2006), s. 22-31 ISSN 0027-5107 R&D Projects: GA ČR GA310/03/0437 Institutional research plan: CEZ:AV0Z5039906 Keywords : Single-strand breaks * Genetic polymorphisms * Metabolism Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 4.111, year: 2006

MTHFR polymorphisms C677T and A1298C and associations with IVF outcomes in Brazilian women.

Science.gov (United States)

D'Elia, Priscila Queiroz; dos Santos, Aline Amaro; Bianco, Bianca; Barbosa, Caio Parente; Christofolini, Denise Maria; Aoki, Tsutomu

2014-06-01

The aim of this study was to investigate the association between MTHFR gene polymorphisms and IVF outcomes in Brazilian women undergoing assisted reproduction treatment. A prospective study was conducted in the Human Reproduction Department at the ABC University School of Medicine and the Ideia Fertility Institute between December 2010 and April 2012. The patient population was 82 women undergoing assisted reproduction cycles. The MTHFR polymorphisms C677T and A1298C were evaluated and compared with laboratory results and pregnancy rates. The C677T variant was associated with proportions of mature (P=0.006) and immature (P=0.003) oocytes whereas the A1298C variant was associated with number of oocytes retrieved (P=0.044). The polymorphisms, whether alone or in combination, were not associated with normal fertilization, good-quality embryo or clinical pregnancy rates. This study suggests that the number and maturity of oocytes retrieved may be related to the MTHFR polymorphisms C677T and A1298C. It is believed that folate has a crucial function in human reproduction and that folate deficiency can compromise the function of the metabolic pathways it is involved in, leading to an accumulation of homocysteine. The gene MTHFR encodes the 5-MTHFR enzyme, which is involved in folate metabolism, and C677T/A1298C polymorphisms of this gene are related to decreased enzyme activity and consequent changes in homocysteine concentration. Folate deficiency and hyperhomocysteinaemia can also compromise fertility and lead to pregnancy complications by affecting the development of oocytes, preparation of endometrial receptivity, implantation of the embryo and pregnancy. In folliculogenesis, hyperhomocysteinaemia can activate apoptosis, leading to follicular atresia and affecting the maturity of oocytes and the quality of embryos cultured in vitro. This study was performed to investigate the association between MTHFR polymorphisms and IVF outcomes in women undergoing assisted

Polymorphisms of genes involved in polycyclic aromatic hydrocarbons’ biotransformation and atherosclerosis

Science.gov (United States)

Marinković, Natalija; Pašalić, Daria; Potočki, Slavica

2013-01-01

Polycyclic aromatic hydrocarbons (PAHs) are among the most prevalent environmental pollutants and result from the incomplete combustion of hydrocarbons (coal and gasoline, fossil fuel combustion, byproducts of industrial processing, natural emission, cigarette smoking, etc.). The first phase of xenobiotic biotransformation in the PAH metabolism includes activities of cytochrome P450 from the CYP1 family and microsomal epoxide hydrolase. The products of this biotransformation are reactive oxygen species that are transformed in the second phase through the formation of conjugates with glutathione, glucuronate or sulphates. PAH exposure may lead to PAH-DNA adduct formation or induce an inflammatory atherosclerotic plaque phenotype. Several genetic polymorphisms of genes encoded for enzymes involved in PAH biotransformation have been proven to lead to the development of diseases. Enzyme CYP P450 1A1, which is encoded by the CYP1A1 gene, is vital in the monooxygenation of lipofilic substrates, while GSTM1 and GSTT1 are the most abundant isophorms that conjugate and neutralize oxygen products. Some single nucleotide polymorphisms of the CYP1A1 gene as well as the deletion polymorphisms of GSTT1 and GSTM1 may alter the final specific cellular inflammatory respond. Occupational exposure or conditions from the living environment can contribute to the production of PAH metabolites with adverse effects on human health. The aim of this study was to obtain data on biotransformation and atherosclerosis, as well as data on the gene polymorphisms involved in biotransformation, in order to better study gene expression and further elucidate the interaction between genes and the environment. PMID:24266295

Towards the development of an enzyme replacement therapy for the metabolic disorder propionic acidemia

Directory of Open Access Journals (Sweden)

Mahnaz Darvish-Damavandi

2016-09-01

Full Text Available Propionic acidemia (PA is a life-threatening disease caused by the deficiency of a mitochondrial biotin-dependent enzyme known as propionyl coenzyme-A carboxylase (PCC. This enzyme is responsible for degrading the metabolic intermediate, propionyl coenzyme-A (PP-CoA, derived from multiple metabolic pathways. Currently, except for drastic surgical and dietary intervention that can only provide partial symptomatic relief, no other form of therapeutic option is available for this genetic disorder. Here, we examine a novel approach in protein delivery by specifically targeting and localizing our protein candidate of interest into the mitochondrial matrix of the cells. In order to test this concept of delivery, we have utilized cell penetrating peptides (CPPs and mitochondria targeting sequences (MTS to form specific fusion PCC protein, capable of translocating and localizing across cell membranes. In vitro delivery of our candidate fusion proteins, evaluated by confocal images and enzymatic activity assay, indicated effectiveness of this strategy. Therefore, it holds immense potential in creating a new paradigm in site-specific protein delivery and enzyme replacement therapeutic for PA.

Association of plasminogen activator inhibitor-1 and angiotensin converting enzyme polymorphisms with recurrent pregnancy loss in Iranian women

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Fatemeh Shakarami

2015-10-01

Full Text Available Background: Recurrent pregnancy loss (RPL defined by two or more failed pregnancies before 20 weeks of gestation. Several factors play a role in RPL including thrombophilic conditions which can be influenced by gene polymorphisms. Plasminogen activator inhibitor-1 (PAI-1 and angiotensin converting enzyme (ACE genes are closely related to fibrinolytic process, embryonic development and pregnancy success. Objective: The aim of this study was to investigate the relationship between RPL and common polymorphisms in ACE and PAI-1 genes. Materials and Methods: In this case control study, 100 women with recurrent abortions (at least two were selected as cases and 100 healthy women with two or more normal term deliveries without a history of abortion as controls. Total genomic DNA was isolated from blood leukocytes. The status of the PAI-1 4G/5G and ACE (D/I polymorphism was determined by PCR-RFLP. Results: Homozygosity for PAI-1 4G polymorphism was seen in 17 cases (17%, and 5 controls (5% (p=0.006 so patients with homozygote 4G mutation were significantly more prone to RPL in contrast to control group (OR: 4.63, % 95 CI: 1.55-13.84. In addition, 7 patients (7 %, and no one from the control group, were homozygote (I/I for ACE polymorphism (p=0.034, suggesting no significant associations between ACE D allele or DD genotype and RPL. Conclusion: Considering these results, because 4G/4G polymorphism for PAI-1 gene could be a thrombophilic variant leading to abortion, analysis of this mutation and other susceptibility factors are recommended in patients with RPL.

Genetic polymorphisms in CYP1A1, GSTM1, GSTP1 and GSTT1 metabolic genes and risk of lung cancer in Asturias

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López-Cima, M Felicitas; Álvarez-Avellón, Sara M; Pascual, Teresa; Fernández-Somoano, Ana; Tardón, Adonina

2012-01-01

Metabolic genes have been associated with the function of metabolizing and detoxifying environmental carcinogens. Polymorphisms present in these genes could lead to changes in their metabolizing and detoxifying ability and thus may contribute to individual susceptibility to different types of cancer. We investigated if the individual and/or combined modifying effects of the CYP1A1 MspI T6235C, GSTM1 present/null, GSTT1 present/null and GSTP1 Ile105Val polymorphisms are related to the risk of developing lung cancer in relation to tobacco consumption and occupation in Asturias, Northern Spain. A hospital-based case–control study (CAPUA Study) was designed including 789 lung cancer patients and 789 control subjects matched in ethnicity, age, sex, and hospital. Genotypes were determined by PCR or PCR-RFLP. Individual and combination effects were analysed using an unconditional logistic regression adjusting for age, pack-years, family history of any cancer and occupation. No statistically significant main effects were observed for the carcinogen metabolism genes in relation to lung cancer risk. In addition, the analysis did not reveal any significant gene-gene, gene-tobacco smoking or gene-occupational exposure interactions relative to lung cancer susceptibility. Lastly, no significant gene-gene combination effects were observed. These results suggest that genetic polymorphisms in the CYP1A1, GSTM1, GSTT1 and GSTP1 metabolic genes were not significantly associated with lung cancer risk in the current study. The results of the analysis of gene-gene interactions of CYP1A1 MspI T6235C, GSTM1 present/null, GSTT1 present/null and GSTP1 Ile105Val polymorphisms in lung cancer risk indicate that these genes do not interact in lung cancer development

Association of Angiotensin-Converting Enzyme (ACE) Gene Polymorphism with Inflammation and Cellular Cytotoxicity in Vitiligo Patients.

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Rashed, Laila; Abdel Hay, Rania; Mahmoud, Rania; Hasan, Nermeen; Zahra, Amr; Fayez, Salwa

2015-01-01

Vitiligo is a disorder with profound heterogeneity in its aetio-pathophysiology. Angiotensin converting enzyme (ACE) plays an important role in the physiology of the vasculature, blood pressure and inflammation. An insertion/deletion (I/D) polymorphism of the ACE gene was reported be associated with the development of vitiligo. Our aim was to evaluate the ACE I/D polymorphism in vitiligo patients and controls. Our second aim was to find a possible association between ACE gene polymorphism and inflammatory mediators (as interleukin (IL)-6) and/or cellular cytotoxicity induced by serum nitrite (as a breakdown product of the cytotoxic nitric oxide) in vitiligo patients. This case-control study included 74 vitiligo patients and 75 apparently healthy controls. The distribution of ACE gene I/D genotype was investigated using PCR. Serum ACE, IL-6 and nitrite were measured by colorimetric method, ELISA and Griess assay respectively. The ACE allele frequency was significantly different between vitiligo patients and healthy controls (P = 0.026). However there was no significant difference between the ACE genotyping frequency in both groups (P = 0.115). There were statistically significant higher VIDA score (P = 0.007), and serum IL-6 (P ACE, IL-6 and nitrite in vitiligo patients were statistically significantly higher than those in controls. As a conclusion, ACE gene polymorphism might grant susceptibility to develop vitiligo. Serum IL-6 and nitrite levels might have an important role in the pathogenesis of vitiligo. Targeting these two factors might have an implication in the treatment of some resistant cases.

Association of CYP1A1 gene polymorphism with chronic kidney disease: a case control study.

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Siddarth, Manushi; Datta, Sudip K; Ahmed, Rafat S; Banerjee, Basu D; Kalra, Om P; Tripathi, Ashok K

2013-07-01

CYP1A1 is an important xenobiotic metabolizing enzyme, present in liver and kidney. Expression of CYP1A1 enzyme increases manifold when kidney cells are exposed to nephrotoxins/chemicals leading to oxidative stress-induced cell damage. To study the association of CYP1A1 gene polymorphism in patients of chronic kidney disease with unknown etiology (CKDU), we recruited 334 CKDU patients and 334 age and sex matched healthy controls. CYP1A1*2A and *2C polymorphisms were studied by PCR-RFLP and allele specific-PCR respectively. Subjects carrying at least one mutant allele of CYP1A1*2A (TC, CC) and *2C (AG, GG) were shown to be associated with 1.4-2-fold increased risk of CKDU. Also, genotypic combinations of hetero-/homozygous mutants of CYP1A1*2A (TC, CC) with hetero-/homozygous mutant genotypes of CYP1A1*2C (AG, GG) i.e. TC/AG (pCKDU with an odd ratio ranging 1.8-3.3 times approximately. This study demonstrates association of CYP1A1 polymorphisms with CKDU. Copyright © 2013 Elsevier B.V. All rights reserved.

Regulation of sucrose metabolism in higher plants: localization and regulation of activity of key enzymes

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Winter, H.; Huber, S. C.; Brown, C. S. (Principal Investigator)

2000-01-01

Sucrose (Suc) plays a central role in plant growth and development. It is a major end product of photosynthesis and functions as a primary transport sugar and in some cases as a direct or indirect regulator of gene expression. Research during the last 2 decades has identified the pathways involved and which enzymes contribute to the control of flux. Availability of metabolites for Suc synthesis and 'demand' for products of sucrose degradation are important factors, but this review specifically focuses on the biosynthetic enzyme sucrose-phosphate synthase (SPS), and the degradative enzymes, sucrose synthase (SuSy), and the invertases. Recent progress has included the cloning of genes encoding these enzymes and the elucidation of posttranslational regulatory mechanisms. Protein phosphorylation is emerging as an important mechanism controlling SPS activity in response to various environmental and endogenous signals. In terms of Suc degradation, invertase-catalyzed hydrolysis generally has been associated with cell expansion, whereas SuSy-catalyzed metabolism has been linked with biosynthetic processes (e.g., cell wall or storage products). Recent results indicate that SuSy may be localized in multiple cellular compartments: (1) as a soluble enzyme in the cytosol (as traditionally assumed); (2) associated with the plasma membrane; and (3) associated with the actin cytoskeleton. Phosphorylation of SuSy has been shown to occur and may be one of the factors controlling localization of the enzyme. The purpose of this review is to summarize some of the recent developments relating to regulation of activity and localization of key enzymes involved in sucrose metabolism in plants.

Association of IL-6 and CRP gene polymorphisms with obesity and metabolic disorders in children and adolescents

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Pâmela F. Todendi

2015-06-01

Full Text Available Activation of adipose tissue inflammation is associated with obesity caused by lipid accumulation in adipocytes. Through this activation, proinflammatory cytokines, such as Interleukin-6 (IL-6 and C-reactive protein (CRP seem to influence metabolic disorders. The present study evaluated whether polymorphisms in the CRP (rs1205 and IL-6 (rs1800795, rs2069845 genes are associated with the development of metabolic disorders in children and adolescents. A cross-sectional study was performed, consisting of 470 students from the municipality of Santa Cruz do Sul, Brazil, aged 7-17 years. Body mass index (BMI was classified according to overweight and obesity. Genotyping was performed by real-time Polymerase Chain Reaction(PCR. Anthropometric characteristics, biochemical markers, immunological markers and blood pressure were assessed. Descriptive statistics, chi-square and logistic regression were used for the analyses. No association was detected between the rs1800795 polymorphism and the assessed variables. Individuals with the risk genotype in the rs1205 gene were associated with the risk of developing hypercholesterolemia (OR 2.79; CI 1.40, 5.57; p = 0.003. Carriers of the risk genotype in the rs2069845 gene are associated with the risk of developing obesity (OR 3.07; CI 1.08, 8.72; p = 0.03. The polymorphism rs2069845 was associated with obesity and rs1205 was associated with the risk of developing hypercholesterolemia in Brazilian schoolchildren.

Genetic variability in chronic irradiated plant populations - Polymorphism and activity of antioxidant enzymes in chronic irradiated plant populations

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Volkova, Polina Y.; Geras' kin, Stanislav A. [Russian Institute of Agricultural Radiology and Agroecology, 249030, Obninsk, Kievskoe shosse 109 km (Russian Federation)

2014-07-01

Introduction: The gene pool of natural population is constantly changing in order to provide the greatest fitness at this time. Ability of population to adapt to changing environmental conditions depends on genetic polymorphism of traits which are operates by selection. Chronic stress exposure can change amount or structure intra-population variability. Therefore, it is necessary to analyze the relationships between genetic polymorphism and stress factors, such as radiation exposure. This studies my assist in the development of new bio-indication methods. Materials and methods: Studying sites: Bryansk region is the most contaminated region of Russia as a result of Chernobyl accident. The initial activity by {sup 137}Cs on this territory reached 1 MBq/m{sup 2} above surface. Our study conducted in several districts of Bryansk region, which are characterized the most dose rate. Experimental sites similar to climate characteristics, stand of trees is homogeneous, pine trees take up a significant part of phytocenosis. Heavy metals content in soils and cones be within background. Dose rates vary from 0.14 to 130 mGy/year. Object: Pinus sylvestris L.,the dominant tree species in North European and Asian boreal forests. Scots pine has a long maturation period (18-20 month), which means that significant DNA damage may accumulate in the undifferentiated stem cells, even at low doses (or dose rates) during exposure to low concentrations of contaminants Isozyme analysis: We evaluated isozyme polymorphism of three antioxidant enzymes: superoxide dismutase, glutatione reductase and glutatione peroxidase. Analysis of enzymes activities: We chose key enzymes of antioxidant system for this experiment: superoxide dismutase, catalase and peroxidase. Results and conclusions: We estimated frequency of each allele in reference and experimental populations. based It was showed that frequency of rare alleles increase in chronic irradiated populations, i.e. increase the sampling variance

Developmental changes in drug-metabolizing enzyme expression during metamorphosis of Xenopus tropicalis.

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Mori, Junpei; Sanoh, Seigo; Kashiwagi, Keiko; Hanada, Hideki; Shigeta, Mitsuki; Suzuki, Ken-Ichi T; Yamamoto, Takashi; Kotake, Yaichiro; Sugihara, Kazumi; Kitamura, Shigeyuki; Kashiwagi, Akihiko; Ohta, Shigeru

2017-01-01

A large number of chemicals are routinely detected in aquatic environments, and these chemicals may adversely affect aquatic organisms. Accurate risk assessment requires understanding drug-metabolizing systems in aquatic organisms because metabolism of these chemicals is a critical determinant of chemical bioaccumulation and related toxicity. In this study, we evaluated mRNA expression levels of nuclear receptors and drug-metabolizing enzymes as well as cytochrome P450 (CYP) activities in pro-metamorphic tadpoles, froglets, and adult frogs to determine how drug-metabolizing systems are altered at different life stages. We found that drug-metabolizing systems in tadpoles were entirely immature, and therefore, tadpoles appeared to be more susceptible to chemicals compared with metamorphosed frogs. On the other hand, cyp1a mRNA expression and CYP1A-like activity were higher in tadpoles. We found that thyroid hormone (TH), which increases during metamorphosis, induced CYP1A-like activity. Because endogenous TH concentration is significantly increased during metamorphosis, endogenous TH would induce CYP1A-like activity in tadpoles.

Terminalia pallida fruit ethanolic extract ameliorates lipids, lipoproteins, lipid metabolism marker enzymes and paraoxonase in isoproterenol-induced myocardial infarcted rats

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Althaf Hussain Shaik

2018-03-01

Full Text Available The present study aimed to evaluate the effect of Terminalia pallida fruit ethanolic extract (TpFE on lipids, lipoproteins, lipid metabolism marker enzymes and paraoxonase (PON in isoproterenol (ISO-induced myocardial infarcted rats. PON is an excellent serum antioxidant enzyme which involves in the protection of low density lipoprotein cholesterol (LDL-C from the process of oxidation for the prevention of cardiovascular diseases. ISO caused a significant increase in the concentration of total cholesterol, triglycerides, LDL-C, very low density lipoprotein cholesterol and lipid peroxidation whereas significant decrease in the concentration of high density lipoprotein cholesterol. ISO administration also significantly decreased the activities of lecithin cholesterol acyl transferase, PON and lipoprotein lipase whereas significantly increased the activity of 3-hydroxy-3-methylglutaryl-coenzyme-A reductase. Oral pretreatment of TpFE at doses 100, 300 and 500 mg/kg body weight (bw and gallic acid (15 mg/kg bw for 30 days challenged with concurrent injection of ISO (85 mg/kg bw on 29th and 30th day significantly attenuated these alterations and restored the levels of lipids, lipoproteins and the activities of lipid metabolizing enzymes. Also TpFE significantly elevated the serum antioxidant enzyme PON. This is the first report revealed that pretreatment with TPFE ameliorated lipid metabolic marker enzymes and increased the antioxidant PON in ISO treated male albino Wistar rats. Keywords: Terminalia pallida fruit, Gallic acid, Isoproterenol, Lipid metabolism marker enzymes, Paraoxonase, Myocardial infarction

Angiotensin-converting enzyme gene polymorphism in arrhythmogenic right ventricular dysplasia: is DD genotype helpful in predicting syncope risk?

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Ozben, Beste; Altun, Ibrahim; Sabri Hancer, Veysel; Bilge, Ahmet Kaya; Tanrikulu, Azra Meryem; Diz-Kucukkaya, Reyhan; Fak, Ali Serdar; Yilmaz, Ercument; Adalet, Kamil

2008-12-01

Arrhythmogenic right ventricular dysplasia (ARVD) is a heritable disorder characterised by fibrofatty replacement of right ventricular myocytes and increased risk of ventricular arrhythmias and sudden cardiac death. Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism affects myocardial ACE levels. DD genotype favours myocardial fibrosis and is associated with malignant ventricular tachycardia. The aim of this study was to explore ACE gene polymorphism in ARVD patients. Twenty-nine patients with ARVD and 24 controls were included. All ARVD patients had documented sustained ventricular tachycardia. Thirteen patients had syncopal episodes. Six patients were resuscitated from sudden cardiac death. ACE gene polymorphism was identified by polymerase chain reaction technique. There was no significant difference in DD genotype frequency between ARVD patients and controls (44.8% vs. 45.8%, p=0.94). However, DD genotype frequency was significantly higher in ARVD patients with syncopal episodes compared to those without syncope (69.2% vs. 25.0%, p=0.017, odds ratio:6.750, 95% confidence interval: 1.318-34.565). DD genotype was detected in higher frequency also in patients with a family history of sudden cardiac death (66.7% vs. 39.1%,p=0.36). High prevalence of DD genotype in ARVD patients with syncope suggests that ACE I/D polymorphism might be useful in identifying high-risk patients for syncope.

Photoperiodism and enzyme activity: towards a model for the control of circadian metabolic rhythms in the crassulacean Acid metabolism.

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Queiroz, O; Morel, C

1974-04-01

Metabolic readjustments after a change from long days to short days appear, in Kalanchoe blossfeldiana, to be achieved through the operation of two main mechanisms: variation in enzyme capacity, and circadian rhythmicity. After a lag time, capacity in phosphoenolpyruvate carboxylase and capacity in aspartate aminotransferase increase exponentially and appear to be allometrically linked during 50 to 60 short days; then a sudden fall takes place in the activity of the former. Malic enzyme and alanine aminotransferase behave differently. Thus, the operation of the two sections of the pathway (before and after the malate step) give rise to a continuously changing functional compartmentation in the pathway. Circadian rhythmicity, on the other hand, produces time compartmentation through phase shifts and variation in amplitude, independently for each enzyme. These characteristics suggest that the operation of a so-called biological clock would be involved. We propose the hypothesis that feedback regulation would be more accurate and efficient when applied to an already oscillating, clock-controlled enzyme system.

A Model of Oxidative Stress Management: Moderation of Carbohydrate Metabolizing Enzymes in SOD1-Null Drosophila melanogaster

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Bernard, Kristine E.; Parkes, Tony L.; Merritt, Thomas J. S.

2011-01-01

The response to oxidative stress involves numerous genes and mutations in these genes often manifest in pleiotropic ways that presumably reflect perturbations in ROS-mediated physiology. The Drosophila melanogaster SOD1-null allele (cSODn108) is proposed to result in oxidative stress by preventing superoxide breakdown. In SOD1-null flies, oxidative stress management is thought to be reliant on the glutathione-dependent antioxidants that utilize NADPH to cycle between reduced and oxidized form. Previous studies suggest that SOD1-null Drosophila rely on lipid catabolism for energy rather than carbohydrate metabolism. We tested these connections by comparing the activity of carbohydrate metabolizing enzymes, lipid and triglyceride concentration, and steady state NADPH:NADP+ in SOD1-null and control transgenic rescue flies. We find a negative shift in the activity of carbohydrate metabolizing enzymes in SOD1-nulls and the NADP+-reducing enzymes were found to have significantly lower activity than the other enzymes assayed. Little evidence for the catabolism of lipids as preferential energy source was found, as the concentration of lipids and triglycerides were not significantly lower in SOD1-nulls compared with controls. Using a starvation assay to impact lipids and triglycerides, we found that lipids were indeed depleted in both genotypes when under starvation stress, suggesting that oxidative damage was not preventing the catabolism of lipids in SOD1-null flies. Remarkably, SOD1-nulls were also found to be relatively resistant to starvation. Age profiles of enzyme activity, triglyceride and lipid concentration indicates that the trends observed are consistent over the average lifespan of the SOD1-nulls. Based on our results, we propose a model of physiological response in which organisms under oxidative stress limit the production of ROS through the down-regulation of carbohydrate metabolism in order to moderate the products exiting the electron transport chain. PMID

Polymorphisms in GSTT1, GSTM1, NAT1 and NAT2 genes and bladder cancer risk in men and women

International Nuclear Information System (INIS)

McGrath, Monica; Michaud, Dominique; De Vivo, Immaculata

2006-01-01

Cigarette smoking is an established risk factor for bladder cancer. Epidemiological and biological data suggest that genetic polymorphisms in activating and detoxifying enzymes may play a role in determining an individual's susceptibility to bladder cancer in particular when in combination with specific environmental exposures such as cigarette smoking. N-acetyltransferase (NAT) enzymes, NAT1 and NAT2, are involved in the activation and detoxification of tobacco smoke constituents. Polymorphisms in these genes alter the ability of these enzymes to metabolize carcinogens, as certain allelic combinations result in a slow or rapid acetylation phenotype. Glutathione S-transferases (GSTs) also detoxify tobacco smoke constituents, and polymorphisms within the GSTM1 and GSTT1 genes can result in a complete lack of enzyme activity. We assessed the association between common polymorphisms identified in the GSTM1, GSTT1, NAT1, and NAT2 genes and the risk of bladder cancer in two nested case-control studies within the Nurses' Health Study (n = 78 female cases, 234 female controls) and the Health Professionals' Follow-up Study (n = 139 male cases, 293 male controls). We also evaluated whether cigarette smoking modified the associations of the genotypes and bladder cancer risk in men and women. Overall, we observed no statistically significant associations between the polymorphisms and bladder cancer risk among men and women, although given our sample size, we had limited power to detect small to moderate effects. There was however the suggestion of an increased risk among female ever smokers with the NAT2 slow genotype and an increased risk in male never smokers with the GSTM1 null genotype. In summary, these prospective results are consistent with previous literature supporting associations between bladder cancer and the NAT2 slow acetylation and the GSTM1 null genotypes

Single nucleotide polymorphisms of one-carbon metabolism and cancers of the esophagus, stomach, and liver in a Chinese population.

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Shen-Chih Chang

Full Text Available One-carbon metabolism (folate metabolism is considered important in carcinogenesis because of its involvement in DNA synthesis and biological methylation reactions. We investigated the associations of single nucleotide polymorphisms (SNPs in folate metabolic pathway and the risk of three GI cancers in a population-based case-control study in Taixing City, China, with 218 esophageal cancer cases, 206 stomach cancer cases, 204 liver cancer cases, and 415 healthy population controls. Study participants were interviewed with a standardized questionnaire, and blood samples were collected after the interviews. We genotyped SNPs of the MTHFR, MTR, MTRR, DNMT1, and ALDH2 genes, using PCR-RFLP, SNPlex, or TaqMan assays. To account for multiple comparisons and reduce the chances of false reports, we employed semi-Bayes (SB shrinkage analysis. After shrinkage and adjusting for potential confounding factors, we found positive associations between MTHFR rs1801133 and stomach cancer (any T versus C/C, SB odds-ratio [SBOR]: 1.79, 95% posterior limits: 1.18, 2.71 and liver cancer (SBOR: 1.51, 95% posterior limits: 0.98, 2.32. There was an inverse association between DNMT1 rs2228612 and esophageal cancer (any G versus A/A, SBOR: 0.60, 95% posterior limits: 0.39, 0.94. In addition, we detected potential heterogeneity across alcohol drinking status for ORs relating MTRR rs1801394 to esophageal (posterior homogeneity P = 0.005 and stomach cancer (posterior homogeneity P = 0.004, and ORs relating MTR rs1805087 to liver cancer (posterior homogeneity P = 0.021. Among non-alcohol drinkers, the variant allele (allele G of these two SNPs was inversely associated with the risk of these cancers; while a positive association was observed among ever-alcohol drinkers. Our results suggest that genetic polymorphisms related to one-carbon metabolism may be associated with cancers of the esophagus, stomach, and liver. Heterogeneity across alcohol consumption status of

Alginate Immobilization of Metabolic Enzymes (AIME) for High ...

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Alginate Immobilization of Metabolic Enzymes (AIME) for High-Throughput Screening Assays DE DeGroot, RS Thomas, and SO SimmonsNational Center for Computational Toxicology, US EPA, Research Triangle Park, NC USAThe EPA’s ToxCast program utilizes a wide variety of high-throughput screening (HTS) assays to assess chemical perturbations of molecular and cellular endpoints. A key criticism of using HTS assays for toxicity assessment is the lack of xenobiotic metabolism (XM) which precludes both metabolic detoxification as well as bioactivation of chemicals tested in vitro thereby mischaracterizing the potential risk posed by these chemicals. To address this deficiency, we have developed an extracellular platform to retrofit existing HTS assays with XM activity. This platform utilizes the S9 fraction of liver homogenate encapsulated in an alginate gel network which reduces the cytotoxicity caused by direct addition of S9 to cells in culture. Alginate microspheres containing encapsulated human liver S9 were cross-linked to solid supports extending from a 96-well plate lid and were assayed using a pro-luciferin substrate specific for CYP3A4 (IPA). We demonstrate that S9 was successfully encapsulated and remained enzymatically active post-encapsulation with 5-10X the CYP3A4 activity as compared to 1 µg solubilized human liver S9. Ketoconazole, a known inhibitor of human CYP3A4, inhibited CYP3A4 activity in a concentration-dependent manner (IC50: 0.27 µM) and inhibiti

Angiotensin-converting enzyme DD polymorphism is associated with poor coronary collateral circulation in patients with coronary artery disease.

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Ceyhan, Koksal; Kadi, Hasan; Celik, Atac; Burucu, Turgay; Koc, Fatih; Sogut, Erkan; Sahin, Semsettin; Onalan, Orhan

2012-01-01

Although association between angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism and cardiovascular diseases was reported by many studies, the relation between ACE I/D polymorphism and coronary collateral circulation (CCC) has not been studied yet. The aim of the present study was to investigate a possible relationship between ACE I/D polymorphism and CCC. Patients who were subjected to coronary angiography in the 2006 to 2009 period and had at least a completely occluded major artery were included in this study. To classify collateral circulation, we used the Rentrop classification. Patients were classified as having poor CCC (Rentrop grades 0 to 1) or good CCC (Rentrop grades 2 to 3). Gene polymorphism was detected through the detailed melting curve analysis of polymerase chain reaction products after amplification using real-time polymerase chain reaction method and LightCycler 1.5 apparatus. We prospectively studied 113 patients who had at least 1 totally occluded major epicardial coronary artery. Forty-seven patients had poor CCC and 67 patients had good CCC. There were no differences among groups in age, sex, risk factors, lipid profile, uses of cardiovascular drugs, and number of diseased vessels. Plasma ACE levels were significantly higher in poor CCC group (P DD polymorphism was higher in the poor CCC group (P DD genotype (95% CI, 2.55-12.79; P = 0.001), presence of diabetes (95% CI, 1.03-3.16; P = 0.005), and pulse pressure (95% CI, 1.04-1.56; P = 0.045) were independent determinants of poor coronary collateral development. This study showed that ACE DD polymorphism is associated with poor CCC. Poor collateral circulation in patients carrying the D allele may be associated with endothelial dysfunction and elevated blood ACE levels in these patients.

Human cytochrome-P450 enzymes metabolize N-(2-methoxyphenyl)hydroxylamine, a metabolite of the carcinogens o-anisidine and o-nitroanisole, thereby dictating its genotoxicity.

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Naiman, Karel; Martínková, Markéta; Schmeiser, Heinz H; Frei, Eva; Stiborová, Marie

2011-12-24

N-(2-Methoxyphenyl)hydroxylamine is a component in the human metabolism of two industrial and environmental pollutants and bladder carcinogens, viz. 2-methoxyaniline (o-anisidine) and 2-methoxynitrobenzene (o-nitroanisole), and it is responsible for their genotoxicity. Besides its capability to form three deoxyguanosine adducts in DNA, N-(2-methoxyphenyl)-hydroxylamine is also further metabolized by hepatic microsomal enzymes. To investigate its metabolism by human hepatic microsomes and to identify the major microsomal enzymes involved in this process are the aims of this study. N-(2-Methoxyphenyl)hydroxylamine is metabolized by human hepatic microsomes predominantly to o-anisidine, one of the parent carcinogens from which N-(2-methoxyphenyl)hydroxylamine is formed, while o-aminophenol and two N-(2-methoxyphenyl)hydroxylamine metabolites, whose exact structures have not been identified as yet, are minor products. Selective inhibitors of microsomal CYPs, NADPH:CYP reductase and NADH:cytochrome-b(5) reductase were used to characterize human liver microsomal enzymes reducing N-(2-methoxyphenyl)hydroxylamine to o-anisidine. Based on these studies, we attribute the main activity for this metabolic step in human liver to CYP3A4, 2E1 and 2C (more than 90%). The enzymes CYP2D6 and 2A6 also partake in this N-(2-methoxyphenyl)hydroxylamine metabolism in human liver, but only to ∼6%. Among the human recombinant CYP enzymes tested in this study, human CYP2E1, followed by CYP3A4, 1A2, 2B6 and 2D6, were the most efficient enzymes metabolizing N-(2-methoxyphenyl)hydroxylamine to o-anisidine. The results found in this study indicate that genotoxicity of N-(2-methoxyphenyl)hydroxylamine is dictated by its spontaneous decomposition to nitrenium/carbenium ions generating DNA adducts, and by its susceptibility to metabolism by CYP enzymes. Copyright © 2011 Elsevier B.V. All rights reserved.

Activity of carbohydrate metabolism enzymes of bone marrow cells of rats affected by radiation

International Nuclear Information System (INIS)

Sukhomlinov, B.F.; Grinyuk, Yu.S.; Sibirnaya, N.A.; Starikovich, L.S.; Khmil', M.V.

1990-01-01

The influence of ionizing radiation (154.8 mC/kg on activity of some carbohydrate metabolism dehydrogenases in cells of the whole and fractionated rat bone marrow has been investigated. Different glucose metabolism units differently responded to radiation, the highest radiation response being exhibited by pentosophosphate cycle processes. The pattern of changes in the enzyme activity of different myelocaryocyte populations was shown to depend directly on the functional specilization of cells and the energy exchange types predominated in them

Association of Angiotensin-Converting Enzyme ACE Gene Polymorphism with ACE Activity and Susceptibility to Vitiligo in Egyptian Population.

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Badran, Dahlia I; Nada, Hesham; Hassan, Ranya

2015-05-01

The insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene is associated with vitiligo in the Indians and Koreans, but not in those of English or Turkish background. We investigated the ACE (I/D) polymorphism in vitiligo patients for the first time in Egypt and compared serum ACE levels between vitiligo patients and controls. The present study was carried out in 100 vitiligo patients (40 males and 60 females) and in 100 healthy controls of an Egyptian population using the polymerase chain reaction genotyping method. The ACE genotype and allele frequency was significantly different between vitiligo patients and controls. Our results revealed a significant increase in the frequency of the ACE I allele (p=0.002; odds ratio: 1.99; 95% confidence intervals: 1.207-3.284) with an overrepresentation of I/D genotype in the vitiligo patient group. Furthermore, there was a significant difference between the segmental, nonsegmental, and focal vitiligo in ACE gene genotype distribution. Serum ACE levels were significantly increased in vitiligo patients compared to controls (p=0.034). This study suggests that, for the first time, ACE gene polymorphism confers susceptibility to vitiligo in the Egyptian population.

Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

International Nuclear Information System (INIS)

Hsieh, Yi-Chen; Lien, Li-Ming; Chung, Wen-Ting; Hsieh, Fang-I; Hsieh, Pei-Fan; Wu, Meei-Maan; Tseng, Hung-Pin; Chiou, Hung-Yi; Chen, Chien-Jen

2011-01-01

Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 μg/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 μg/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 μg/l). - Highlights: →Arsenic metabolic genes might be associated with carotid atherosclerosis. → A case

Significantly increased risk of carotid atherosclerosis with arsenic exposure and polymorphisms in arsenic metabolism genes

Energy Technology Data Exchange (ETDEWEB)

Hsieh, Yi-Chen [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Lien, Li-Ming [Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China); School of Medicine, Taipei Medical University, Taipei, Taiwan (China); Department of Neurology, Shin Kong WHS Memorial Hospital, Taipei, Taiwan (China); Chung, Wen-Ting [Department of Neurology, Wanfang Hospital, Taipei Medical University, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, Taipei Medical University, Taipei, Taiwan (China); Hsieh, Fang-I; Hsieh, Pei-Fan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Wu, Meei-Maan [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Graduate Institute of Basic Medicine, College of Medicine, Fu-Jen Catholic University, Taipei, Taiwan (China); Tseng, Hung-Pin [Department of Neurology, Lotung Poh-Ai Hospital, I-Lan, Taiwan (China); Chiou, Hung-Yi, E-mail: hychiou@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, 250 Wusing St., Taipei 11031, Taiwan (China); Chen, Chien-Jen [Genomics Research Center, Academia Sinica, Taipei, Taiwan (China)

2011-08-15

Individual susceptibility to arsenic-induced carotid atherosclerosis might be associated with genetic variations in arsenic metabolism. The purpose of this study is to explore the interaction effect on risk of carotid atherosclerosis between arsenic exposure and risk genotypes of purine nucleoside phosphorylase (PNP), arsenic (+3) methyltransferase (As3MT), and glutathione S-transferase omega 1 (GSTO1) and omega 2 (GSTO2). A community-based case-control study was conducted in northeastern Taiwan to investigate the arsenic metabolic-related genetic susceptibility to carotid atherosclerosis. In total, 863 subjects, who had been genotyped and for whom the severity of carotid atherosclerosis had been determined, were included in the present study. Individual well water was collected and arsenic concentration determined using hydride generation combined with flame atomic absorption spectrometry. The result showed that a significant dose-response trend (P=0.04) of carotid atherosclerosis risk associated with increasing arsenic concentration. Non-significant association between genetic polymorphisms of PNP Gly51Ser, Pro57Pro, As3MT Met287Thr, GSTO1 Ala140Asp, and GSTO2 A-183G and the risk for development of carotid atherosclerosis were observed. However, the significant interaction effect on carotid atherosclerosis risk was found for arsenic exposure (>50 {mu}g/l) and the haplotypes of PNP (p=0.0115). A marked elevated risk of carotid atherosclerosis was observed in subjects with arsenic exposure of >50 {mu}g/l in drinking water and those who carried the PNP A-T haplotype and at least either of the As3MT risk polymorphism or GSTO risk haplotypes (OR, 6.43; 95% CI, 1.79-23.19). In conclusion, arsenic metabolic genes, PNP, As3MT, and GSTO, may exacerbate the formation of atherosclerosis in individuals with high levels of arsenic concentration in well water (>50 {mu}g/l). - Highlights: {yields}Arsenic metabolic genes might be associated with carotid atherosclerosis. {yields

Genetic Variation in Choline-Metabolizing Enzymes Alters Choline Metabolism in Young Women Consuming Choline Intakes Meeting Current Recommendations

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Ariel B. Ganz

2017-01-01

Full Text Available Single nucleotide polymorphisms (SNPs in choline metabolizing genes are associated with disease risk and greater susceptibility to organ dysfunction under conditions of dietary choline restriction. However, the underlying metabolic signatures of these variants are not well characterized and it is unknown whether genotypic differences persist at recommended choline intakes. Thus, we sought to determine if common genetic risk factors alter choline dynamics in pregnant, lactating, and non-pregnant women consuming choline intakes meeting and exceeding current recommendations. Women (n = 75 consumed 480 or 930 mg choline/day (22% as a metabolic tracer, choline-d9 for 10–12 weeks in a controlled feeding study. Genotyping was performed for eight variant SNPs and genetic differences in metabolic flux and partitioning of plasma choline metabolites were evaluated using stable isotope methodology. CHKA rs10791957, CHDH rs9001, CHDH rs12676, PEMT rs4646343, PEMT rs7946, FMO3 rs2266782, SLC44A1 rs7873937, and SLC44A1 rs3199966 altered the use of choline as a methyl donor; CHDH rs9001 and BHMT rs3733890 altered the partitioning of dietary choline between betaine and phosphatidylcholine synthesis via the cytidine diphosphate (CDP-choline pathway; and CHKA rs10791957, CHDH rs12676, PEMT rs4646343, PEMT rs7946 and SLC44A1 rs7873937 altered the distribution of dietary choline between the CDP-choline and phosphatidylethanolamine N-methyltransferase (PEMT denovo pathway. Such metabolic differences may contribute to disease pathogenesis and prognosis over the long-term.

MUREIN-METABOLIZING ENZYMES FROM ESCHERICHIA-COLI - EXISTENCE OF A 2ND LYTIC TRANSGLYCOSYLASE

NARCIS (Netherlands)

ENGEL, H; SMINK, AJ; VANWIJNGAARDEN, L; KECK, W

1992-01-01

In addition to the soluble lytic transglycosylase, a murein-metabolizing enzyme with a molecular mass of 70 kDa (Slt70), Escherichia coli possesses a second lytic transglycosylase, which has been described as a membrane-bound lytic transglycosylase (Mlt; 35 kDa; EC 3.2.1.-). The mlt gene, which

Enzyme allocation problems in kinetic metabolic networks: Optimal solutions are elementary flux modes

Czech Academy of Sciences Publication Activity Database

Müller, Stefan; Regensburger, G.; Steuer, Ralf

2014-01-01

Roč. 347, APR 2014 (2014), s. 182-190 ISSN 0022-5193 R&D Projects: GA MŠk(CZ) EE2.3.20.0256 Institutional support: RVO:67179843 Keywords : metabolic optimization * enzyme kinetics * oriented matroid * elementary vector * conformal sum Subject RIV: EI - Biotechnology ; Bionics Impact factor: 2.116, year: 2014

Impact of androgenic/antiandrogenic compounds (AAC) on human sex steroid metabolizing key enzymes

International Nuclear Information System (INIS)

Allera, A.; Lo, S.; King, I.; Steglich, F.; Klingmueller, D.

2004-01-01

Various pesticides, industrial pollutants and synthetic compounds, to which human populations are exposed, are known or suspected to interfere with endogenous sex hormone functions. Such interference potentially affect the development and expression of the male and female reproductive system or both. Chemicals in this class are thus referred to as endocrine disruptors (ED). This emphazises on the relevance of screening ED for a wide range of sex hormone-mimicking effects. These compounds are believed to exert influence on hormonal actions predominantly by (i) interfering with endogenous steroids in that they functionally interact with plasma membrane-located receptors as well as with nuclear receptors both for estrogens and androgens or (ii) affecting the levels of sex hormones as a result of their impact on steroid metabolizing key enzymes. Essential sex hormone-related enzymes within the endocrine system of humans are aromatase, 5α-reductase 2 as well as specific sulfotransferases and sulfatases (so-called phase I and phase II enzymes, respectively). Using suitable human tissues and human cancer cell lines (placenta, prostate, liver and JEG-3, lymph node carcinoma of prostate (LnCaP) cells) we investigated the impact of 10 widely used chemicals suspected of acting as ED with androgenic or antiandrogenic activity (so-called AAC) on the activity of these sex hormone metabolizing key enzymes in humans. In addition, the respective effects of six substances were also studied as positive controls due to their well-known specific hormonal agonistic/antagonistic activities. The aim of this report and subsequent investigations is to improve human health risk assessment for AAC and other ED

The Frequency of Cytochrome P450 2E1 Polymorphisms in Black South Africans

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Paul K. Chelule

2006-01-01

Full Text Available Polymorphisms in the promoter region of the Cytochrome P4502E1 (CYP2E1 gene reportedly modify the metabolic activity of CYP2E1 enzyme, and have been associated with increased susceptibility to squamous cell carcinoma (SCC of the oesophagus in high prevalence areas such as China. To assess the frequency of these polymorphisms in Black South Africans, a population with a high incidence of oesophageal SCC, this study examined genomic DNA from 331 subjects for restriction fragment length polymorphisms in the CYP2E1 (RsaI and PstI digestion. The frequency of the CYP2E1 c1/c1 and c1/c3 genotypes was 95% and 5% respectively. The frequency of the CYP2E1 allele distribution was found to be markedly different between Chinese and South African populations; hence it is important to place racial differences into consideration when proposing allelic variants as genetic markers for cancer.

Studies of the common DIO2 Thr92Ala polymorphism and metabolic phenotypes in 7342 Danish white subjects

DEFF Research Database (Denmark)

Grarup, Niels; Andersen, Mette K; Andreasen, Camilla H

2007-01-01

The type 2 iodothyronine deiodinase (D2) catalyzes the conversion of T(4) to the active form of thyroid hormone, which is a critical regulator of thermogenesis and glucose metabolism. A Thr92Ala polymorphism in the gene encoding D2 (DIO2) has been reported to associate with insulin resistance....

Impact of HSD11B1 polymorphisms on BMI and components of the metabolic syndrome in patients receiving psychotropic treatments

KAUST Repository

Quteineh, Lina; Vandenberghe, Frederik; Saigi Morgui, Nuria; Delacré taz, Auré lie; Choong, Eva; Gholam-Rezaee, Mehdi; Magistretti, Pierre J.; Bondolfi, Guido; Von Gunten, Armin; Preisig, Martin A.; Castelao, Enrique; Vollenweider, Peter; Waeber, Gé rard; Bochud, Murielle; Kutalik, Zoltá n; Conus, Philippe O.; Eap, Chin Bin

2015-01-01

Background Metabolic syndrome (MetS) associated with psychiatric disorders and psychotropic treatments represents a major health issue. 11β-Hydroxysteroid dehydrogenase type 1 (11β-HSD1) is an enzyme that catalyzes tissue regeneration of active cortisol from cortisone. Elevated enzymatic activity of 11β-HSD1 may lead to the development of MetS. Methods We investigated the association between seven HSD11B1 gene (encoding 11β-HSD1) polymorphisms and BMI and MetS components in a psychiatric sample treated with potential weight gain-inducing psychotropic drugs (n=478). The polymorphisms that survived Bonferroni correction were analyzed in two independent psychiatric samples (n R1 =168, n R2 =188) and in several large population-based samples (n 1 =5338; n 2 =123 865; n 3 >100 000). Results HSD11B1 rs846910-A, rs375319-A, and rs4844488-G allele carriers were found to be associated with lower BMI, waist circumference, and diastolic blood pressure compared with the reference genotype (P corrected <0.05). These associations were exclusively detected in women (n=257) with more than 3.1 kg/m 2, 7.5 cm, and 4.2 mmHg lower BMI, waist circumference, and diastolic blood pressure, respectively, in rs846910-A, rs375319-A, and rs4844488-G allele carriers compared with noncarriers (P corrected <0.05). Conversely, carriers of the rs846906-T allele had significantly higher waist circumference and triglycerides and lower high-density lipoprotein-cholesterol exclusively in men (P corrected =0.028). The rs846906-T allele was also associated with a higher risk of MetS at 3 months of follow-up (odds ratio: 3.31, 95% confidence interval: 1.53-7.17, P corrected =0.014). No association was observed between HSD11B1 polymorphisms and BMI and MetS components in the population-based samples. Conclusions Our results indicate that HSD11B1 polymorphisms may contribute toward the development of MetS in psychiatric patients treated with potential weight gain-inducing psychotropic drugs, but do not

The N363S polymorphism of the glucocorticoid receptor and metabolic syndrome factors in men

DEFF Research Database (Denmark)

Buemann, Benjamin; Black, Eva; Holst, Claus

2005-01-01

with the obese men (n = 299; age, 50 +/- 7 years). The subjects were genotyped for the N363S polymorphism by polymerase chain reaction-restriction fragment length polymorphism. Body composition was measured by DXA. Glucose metabolism was evaluated by an oral glucose tolerance test, and the Matsudas index...... was calculated as a proxy for insulin sensitivity. Serum triglycerides and total and high-density lipoprotein-cholesterol were measured in the fasting state. RESULTS: Among the men with juvenile-onset obesity, carriers (n = 17) of the 363S allele had a lower whole body fat percentage, after accounting...... for differences in BMI and higher Matsudas index, compared with the noncarriers. The difference in Matsudas index lost statistical significance after the difference in body fat was accounted for. In the randomly sampled men, these variables did not relate to genotype. No relationship between carriers...

A genetic study of various enzyme polymorphisms in Pleurodeles waltlii (Urodele Amphibian). II. Peptidases: demonstration of sex linkage.

Science.gov (United States)

Ferrier, V; Gasser, F; Jaylet, A; Cayrol, C

1983-06-01

The existence of four peptidases was demonstrated by starch gel electrophoresis in Pleurodeles waltlii: PEP-1, PEP-2, PEP-3, and PEP-4. Peptidases-3 and -4 are monomorphic, and peptidases-1 and -2 are polymorphic. The heredity of the polymorphisms was studied using individuals arising from crosses or of gynogenetic origin. Peptidase-1 is dimeric; its polymorphism depends on a pair of codominant alleles, Pep-1A and Pep-1B, which are situated on the Z and W sex chromosomes, respectively, in close proximity to, or even within, the sex differential segment. As the differential segment is very close to the centromere, the PEP-1 locus therefore also appears to be closely linked to it. Expression of the PEP-1 locus was shown to be independent of the sex hormone environment. This locus is the first case reported in amphibians of an enzyme marker linked to the genetic sex. It allows the sex of PLeurodeles to be determined before they reach sexual maturity. Peptidase-2 is monomeric. Its polymorphism depends on a pair of codominant alleles on an autosomal PEP-2 locus. The high proportion of heterozygous animals in the gynogenetic offspring of females heterozygous for the PEP-2 locus indicates segregation which is independent of the centromere. Analysis of the offspring of doubly heterozygous females (i.e., for two of the loci--LDH-B, G6PDH, PEP-1, and PEP-2) shows that the four loci are independent.

Molecular mechanisms of mitochondrial DNA depletion diseases caused by deficiencies in enzymes in purine and pyrimidine metabolism.

Science.gov (United States)

Eriksson, Staffan; Wang, Liya

2008-06-01

Mitochondrial DNA depletion syndrome (MDS), a reduction of mitochondrial DNA copy number, often affects muscle or liver. Mutations in enzymes of deoxyribonucleotide metabolism give MDS, for example, the mitochondrial thymidine kinase 2 (TK2) and deoxyguanosine kinase (dGK) genes. Sixteen TK2 and 22 dGK alterations are known. Their characteristics and symptoms are described. Levels of five key deoxynucleotide metabolizing enzymes in mouse tissues were measured. TK2 and dGK levels in muscles were 5- to 10-fold lower than other nonproliferating tissues and 100-fold lower compared to spleen. Each type of tissue apparently relies on de novo and salvage synthesis of DNA precursors to varying degrees.

Quantitative assessment of the association between the angiotensin-converting enzyme gene insertion/deletion polymorphism and digestive system cancer risk.

Science.gov (United States)

Wang, J; Yang, S; Guo, F H; Mao, X; Zhou, H; Dong, Y Q; Wang, Z M; Luo, F

2015-11-13

The angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism has been reported to be associated with digestive system cancer; however, the results from previous studies have been conflicting. The present study aimed to investigate the association between the ACE I/D polymorphism and the risk of digestive system cancer using a meta-analysis of previously published studies. Databases were systematically searched to identify relevant studies published prior to December 2014. We estimated the pooled OR with its 95%CI to assess the association. The meta-analysis consisted of thirteen case-control studies that included 2557 patients and 4356 healthy controls. Meta-analysis results based on all the studies showed no significant association between the ACE I/D polymorphism and the risk of digestive system cancer (DD vs II: OR = 0.85, 95%CI = 0.59-1.24; DI vs II: OR = 0.94, 95%CI = 0.78-1.15; dominant model: OR = 0.96, 95%CI = 0.81- 1.15; recessive model: OR = 1.06, 95%CI = 0.76-1.48). Subgroup analyses by race and cancer type did not detect an association between the ACE I/D polymorphism and digestive system cancer risk. However, when the analyses were restricted to smaller studies (N digestive system cancer. Further large and well-designed studies are needed to confirm these conclusions.

Association between single nucleotide polymorphisms in the antioxidant genes CAT, GR and SOD1, erythrocyte enzyme activities, dietary and life style factors and breast cancer risk in a Danish, prospective cohort study

DEFF Research Database (Denmark)

Kopp, Tine Iskov; Vogel, Ulla; Dragsted, Lars Ove

2017-01-01

investigated in 703 breast cancer case-control pairs in the Danish, prospective "Diet, Cancer and Health" cohort together with gene-environment interactions between the polymorphisms, enzyme activities and intake of fruits and vegetables, alcohol and smoking in relation to breast cancer risk. Our results...... showed that genetically determined variations in the antioxidant enzyme activities of SOD1, CAT and GSR were not associated with risk of breast cancer per se. However, intake of alcohol, fruit and vegetables, and smoking status interacted with some of the polymorphisms in relation to breast cancer risk...

Characterisation of the cytochrome P450 enzymes involved in the in vitro metabolism of granisetron.

OpenAIRE

Bloomer, J C; Baldwin, S J; Smith, G J; Ayrton, A D; Clarke, S E; Chenery, R J

1994-01-01

1. The metabolism of granisetron was investigated in human liver microsomes to identify the specific forms of cytochrome P450 responsible. 2. 7-hydroxy and 9'-desmethyl granisetron were identified as the major products of metabolism following incubation of granisetron with human liver microsomes. At low, clinically relevant, concentrations of granisetron the 7-hydroxy metabolite predominated. Rates of granisetron 7-hydroxylation varied over 100-fold in the human livers investigated. 3. Enzyme...

The subcellular compartmentalization of arginine metabolizing enzymes and their role in endothelial dysfunction

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Feng eChen

2013-07-01

Full Text Available The endothelial production of nitric oxide (NO mediates endothelium-dependent vasorelaxation and restrains vascular inflammation, smooth muscle proliferation and platelet aggregation. Impaired production of NO is a hallmark of endothelial dysfunction and promotes the development of cardiovascular disease. In endothelial cells, NO is generated by endothelial nitric oxide synthase (eNOS through the conversion of its substrate, L-arginine to L-citrulline. Reduced access to L-arginine has been proposed as a major mechanism underlying reduced eNOS activity and NO production in cardiovascular disease. The arginases (Arg1 and Arg2 metabolize L-arginine to generate L-ornithine and urea and increased expression of arginase has been proposed as a mechanism of reduced eNOS activity secondary to the depletion of L-arginine. Indeed, supplemental L-arginine and suppression of arginase activity has been shown to improve endothelium-dependent relaxation and ameliorate cardiovascular disease. However, L-arginine concentrations in endothelial cells remain sufficiently high to support NO synthesis suggesting additional mechanisms. The compartmentalization of intracellular L-arginine into poorly interchangeable pools has been proposed to allow for the local depletion of L-arginine. Indeed the subcellular location of L-arginine metabolizing enzymes plays important functional roles. In endothelial cells, eNOS is found in discrete intracellular locations and the capacity to generate NO is heavily influenced by its localtion. Arg1 and Arg2 also reside in different subcellular environments and are thought to differentially influence endothelial function. The plasma membrane solute transporter, CAT-1 and the arginine recycling enzyme, ASL, co-localize with eNOS and facilitate NO release. This review highlights the importance of the subcellular location of eNOS and arginine transporting and metabolizing enzymes to NO release and cardiovascular disease.

Short communication: expression of transporters and metabolizing enzymes in the female lower genital tract: implications for microbicide research.

Science.gov (United States)

Zhou, Tian; Hu, Minlu; Cost, Marilyn; Poloyac, Samuel; Rohan, Lisa

2013-11-01

Topical vaginal microbicides have been considered a promising option for preventing the male-to-female sexual transmission of HIV; however, clinical trials to date have not clearly demonstrated robust and reproducible effectiveness results. While multiple approaches may help enhance product effectiveness observed in clinical trials, increasing the drug exposure in lower genital tract tissues is a compelling option, given the difficulty in achieving sufficient drug exposure and positive correlation between tissue exposure and microbicide efficacy. Since many microbicide drug candidates are substrates of transporters and/or metabolizing enzymes, there is emerging interest in improving microbicide exposure and efficacy through local modulation of transporters and enzymes in the female lower genital tract. However, no systematic information on transporter/enzyme expression is available for ectocervical and vaginal tissues of premenopausal women, the genital sites most relevant to microbicide drug delivery. The current study utilized reverse transcriptase polymerase chain reaction (RT-PCR) to examine the mRNA expression profile of 22 transporters and 19 metabolizing enzymes in premenopausal normal human ectocervix and vagina. Efflux and uptake transporters important for antiretroviral drugs, such as P-gp, BCRP, OCT2, and ENT1, were found to be moderately or highly expressed in the lower genital tract as compared to liver. Among the metabolizing enzymes examined, most CYP isoforms were not detected while a number of UGTs such as UGT1A1 were highly expressed. Moderate to high expression of select transporters and enzymes was also observed in mouse cervix and vagina. The implications of this information on microbicide research is also discussed, including microbicide pharmacokinetics, the utilization of the mouse model in microbicide screening, as well as the in vivo functional studies of cervicovaginal transporters and enzymes.

Motility, ATP levels and metabolic enzyme activity of sperm from bluegill (Lepomis macrochirus).

Science.gov (United States)

Burness, Gary; Moyes, Christopher D; Montgomerie, Robert

2005-01-01

Male bluegill displays one of two life history tactics. Some males (termed "parentals") delay reproduction until ca. 7 years of age, at which time they build nests and actively courts females. Others mature precociously (sneakers) and obtain fertilizations by cuckolding parental males. In the current study, we studied the relations among sperm motility, ATP levels, and metabolic enzyme activity in parental and sneaker bluegill. In both reproductive tactics, sperm swimming speed and ATP levels declined in parallel over the first 60 s of motility. Although sneaker sperm initially had higher ATP levels than parental sperm, by approximately 30 s postactivation, no differences existed between tactics. No differences were noted between tactics in swimming speed, percent motility, or the activities of key metabolic enzymes, although sperm from parentals had a higher ratio of creatine phosphokinase (CPK) to citrate synthase (CS). In both tactics, with increasing CPK and CS activity, sperm ATP levels increased at 20 s postactivation, suggesting that capacities for phosphocreatine hydrolysis and aerobic metabolism may influence interindividual variation in rates of ATP depletion. Nonetheless, there was no relation between sperm ATP levels and either swimming speed or percent of sperm that were motile. This suggests that interindividual variation in ATP levels may not be the primary determinant of variation in sperm swimming performance in bluegill.

Association of Angiotensin-Converting Enzyme (ACE Gene Polymorphism with Inflammation and Cellular Cytotoxicity in Vitiligo Patients.

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Laila Rashed

Full Text Available Vitiligo is a disorder with profound heterogeneity in its aetio-pathophysiology. Angiotensin converting enzyme (ACE plays an important role in the physiology of the vasculature, blood pressure and inflammation. An insertion/deletion (I/D polymorphism of the ACE gene was reported be associated with the development of vitiligo.Our aim was to evaluate the ACE I/D polymorphism in vitiligo patients and controls. Our second aim was to find a possible association between ACE gene polymorphism and inflammatory mediators (as interleukin (IL-6 and/or cellular cytotoxicity induced by serum nitrite (as a breakdown product of the cytotoxic nitric oxide in vitiligo patients.This case-control study included 74 vitiligo patients and 75 apparently healthy controls. The distribution of ACE gene I/D genotype was investigated using PCR. Serum ACE, IL-6 and nitrite were measured by colorimetric method, ELISA and Griess assay respectively.The ACE allele frequency was significantly different between vitiligo patients and healthy controls (P = 0.026. However there was no significant difference between the ACE genotyping frequency in both groups (P = 0.115. There were statistically significant higher VIDA score (P = 0.007, and serum IL-6 (P < 0.001 in patients with the DD genotype when compared to other genotypes. Serum nitrite in patients with the DD genotype was significantly higher (P = 0.007 when compared to patients with II genotype. Serum levels of ACE, IL-6 and nitrite in vitiligo patients were statistically significantly higher than those in controls.As a conclusion, ACE gene polymorphism might grant susceptibility to develop vitiligo. Serum IL-6 and nitrite levels might have an important role in the pathogenesis of vitiligo. Targeting these two factors might have an implication in the treatment of some resistant cases.

Impact of I/D polymorphism of angiotensin-converting enzyme (ACE) gene on myocardial infarction susceptibility among young Moroccan patients.

Science.gov (United States)

Hmimech, Wiam; Idrissi, Hind Hassani; Diakite, Brehima; Korchi, Farah; Baghdadi, Dalila; Tahri Joutey Hassani Idrissi, Hind; Haboub, Meriem; Habbal, Rachida; Nadifi, Sellama

2017-12-21

Our case-control study aimed to access the potential association of insertion/deletion (I/D) ACE (angiotensin converting enzyme) gene polymorphism with myocardial infarction (MI) risk of occurrence among a sample of Moroccan patients, especially young ones. Distribution of I/D ACE gene variant among cases vs controls, showed that healthy controls carried out higher frequency of wild type allele I compared to cases (23.5% vs 21.79% respectively), when cases were carrying higher frequency of mutant allele D (78.21% vs 76.5% for controls). Patients were-after this- divided into two groups of  55 years of age, to investigate whether or not younger patients carried out higher frequency of the mutant allele D, than older ones. As expected, ACE polymorphism may be associated with MI occurrence among younger patients (< 45 years of age).

Associations between clinical characteristics and angiotensin-converting enzyme gene insertion/deletion polymorphism in Moroccan population with Type-2 diabetic nephropathy

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Maria Mansouri

2017-01-01

Full Text Available Diabetic nephropathy (DN is one of the severe complications of Type-2 diabetes mellitus (T2DM and a major cause of end-stage renal disease in these patients. Results from published studies on the relationship between angiotensin-converting enzyme (ACE insertion/ deletion (I/D gene polymorphism and patients with DN are still conflicting. We compared the clinical characteristics and the genotype frequencies of ACE polymorphism in 130 T2DM Moroccan patients with DN and 85 T2DM Moroccan patients without DN (controls using specific primers in a polymerase chain reaction. The degenerative complications of diabetes were significantly higher in the group with nephropathy. The distribution of the I/D genotypes was in Hardy–Weinberg equilibrium. The D allele was the most frequent allele in the Moroccan population in both groups studied (P = 0.68, however, there was no significant difference between the genotypes in T2DM patients with or without DN (P = 0.78. The ACE gene I/D polymorphism was not associated with an increased risk of DN in the Moroccan population.

Association of insertion/deletion polymorphism of angiotensin-converting enzyme gene among Malay male hypertensive subjects in response to ACE inhibitors.

Science.gov (United States)

Heidari, Farzad; Vasudevan, Ramachandran; Mohd Ali, Siti Zubaidah; Ismail, Patimah; Etemad, Ali; Pishva, Seyyed Reza; Othman, Fauziah; Abu Bakar, Suhaili

2015-12-01

Several studies show that the insertion/deletion (I/D) polymorphism of the angiotensin-converting enzyme (ACE) gene has been associated with hypertension in various populations. The present study sought to determine the association of the I/D gene polymorphism among Malay male essential hypertensive subjects in response to ACE inhibitors (enalapril and lisinopril). A total of 72 patients with newly diagnosed hypertension and 72 healthy subjects were recruited in this study. Blood pressure was recorded from 0 to 24 weeks of treatment with enalapril or lisinopril. Genotyping of the I/D polymorphism was carried out using a standard PCR method. Statistically significant association of the D allele of the ACE gene was observed between the case and control subjects (p ACE gene. Patients carrying the DD genotype had higher blood pressure-lowering response when treated with ACE inhibitors enalapril or lisinopril than those carrying ID and II genotypes, suggesting that the D allele may be a possible genetic marker for essential hypertension among Malay male subjects. © The Author(s) 2014.

Effect of ethylene glycol monomethyl ether and diethylene glycol monomethyl ether on hepatic metabolizing enzymes.

Science.gov (United States)

Kawamoto, T; Matsuno, K; Kayama, F; Hirai, M; Arashidani, K; Yoshikawa, M; Kodama, Y

1990-06-01

Glycol ethers have been extensively used in industry over the past 40-50 years. Numerous studies on the toxicity of glycol ethers have been performed, however, the effects of glycol ethers on the hepatic drug metabolizing enzymes are still unknown. We studied the changes of the putative metabolic enzymes, that is, the hepatic microsomal mixed function oxidase system and cytosolic alcohol dehydrogenase, by the oral administration of diEGME and EGME. Adult male Wistar rats were used. DiEGME was administered orally; 500, 1000, 2000 mg/kg for 1, 2, 5 or 20 days and EGME was 100, 300 mg/kg for 1, 2, 5 or 20 days. Decreases in liver weights were produced by highest doses of diEGME (2000 mg/kg body wt/day for 20 days) and EGME (300 mg/kg body wt/day for 20 days). DiEGME increased hepatic microsomal protein contents and induced cytochrome P-450, but not cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was not affected by diEGME administration. On the other hand, EGME did not change cytochrome P-450, cytochrome b5 or NADPH-cytochrome c reductase. The activity of cytosolic ADH was increased by repeated EGME treatment. Therefore it is suspected that the enzyme which takes part in the metabolism of diEGME is different from that of EGME, although diEGME is a structural homologue of EGME.

The Common C49620T Polymorphism in the Sulfonylurea Receptor Gene SUR1 (ABCC8) in Patients with Gestational Diabetes and Subsequent Glucose Metabolism Abnormalities

Science.gov (United States)

Molęda, Piotr; Bińczak-Kuleta, Agnieszka; Homa, Katarzyna; Safranow, Krzysztof; Celewicz, Zbigniew; Syrenicz, Anhelli; Stefański, Adam; Fronczyk, Aneta; Majkowska, Lilianna

2012-01-01

Aim. The aim of this study is to investigate the relationship between the common C49620T polymorphism in the sulfonylurea receptor (SUR1) gene and glucose metabolism, β-cell secretory function and insulin resistance in women with a history of gestational diabetes (GDM). Material and Methods. Study group included 199 women, diagnosed GDM within the last 5–12 years and control group of comparable 50 women in whom GDM was excluded during pregnancy. Blood glucose and insulin levels were measured during oral glucose tolerance test. Indices of insulin resistance (HOMA-IR) and β-cell function (HOMA %B) were calculated. In all patients, the C49620T polymorphism in intron 15 of the SUR1 gene was determined. Results. The distribution of the studied polymorphism in the two groups did not differ from each other (χ 2 = 0.34, P = 0.8425). No association between the distribution of polymorphisms and coexisting glucose metabolism disorders (χ 2 = 7,13, P = 0, 3043) was found. No association was also observed between the polymorphism and HOMA %B or HOMA-IR. Conclusions. The polymorphism C49620T in the SUR1 gene is not associated with insulin resistance and/or insulin secretion in women with a history of GDM and does not affect the development of GDM, or the development of glucose intolerance in the studied population. PMID:22927833

Association of Angiotensin-Converting Enzyme Intron 16 Insertion/Deletion and Angiotensin II Type 1 Receptor A1166C Gene Polymorphisms with Preeclampsia in South East of Iran

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Saeedeh Salimi

2011-01-01

Full Text Available Some evidence suggests that a variety of genetic factors contributed in pathogenesis of the preeclampsia. The aim of this study was to assess the association between the angiotensin-converting enzyme (ACE I/D and angiotensin II type1 receptor A1166C polymorphisms with preeclampsia. This study was performed in 125 preeclamptic pregnant women and 132 controls. The I/D Polymorphism of the ACE gene was assessed by polymerase chain reaction and the A1166C Polymorphism of the AT1R gene was determined by restriction fragment length polymorphism. The genotype and allele frequencies of I/D polymorphism differed between two groups. The risk of preeclampsia was 3.2-fold in pregnant women with D allele (OR, 3.2 [95% CI, 1.1 to 3.8]; P=0.01. The distribution of the AT1R gene A1166C polymorphism was similar in affected and control groups. Our results supported that presence of the I/D polymorphism of ACE gene is a marker for the increased risk of preeclampsia.

The angiotensin converting enzyme insertion/deletion polymorphism and differences in fasting plasma glucose in Hindustani Surinamese, African Surinamese and ethnic Dutch: the population-based SUNSET-study

NARCIS (Netherlands)

van Valkengoed, Irene G. M.; Stronks, Karien; Hahntow, Ines N.; Hoekstra, Joost B. L.; Holleman, Frits

2008-01-01

We investigated the association between the angiotensin converting enzyme (ACE) insertion/deletion polymorphism and glycemic state. Diabetes mellitus, impaired fasting glucose and mean fasting glucose were not associated with genotype among Hindustani Surinamese, African Surinamese and Dutch

First Analysis of the Association Between CYP3A4/5, ABCB1 Genetic Polymorphisms and Oxcarbazepine Metabolism and Transport in Chinese Epileptic Patients with Oxcarbazepine Monotherapy and Bitherapy.

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Wang, Ping; Yin, Tao; Ma, Hong-ying; Liu, Dan-Qi; Sheng, Yangh-ao; Zhou, Bo-Ting

2015-01-01

Oxcarbazepine (OXC) is widely used in anti-epileptic treatment. Cytochrome P450 3A4 (CYP3A4), cytochrome P450 3A5(CYP3A5), and ATP-binding cassette sub-family B member 1 (ABCB1) are potential genes involved in OXC metabolisms and transport in vivo. This study aims to examine the genetic effects of CYP3A4, CYP3A5, and ABCB1 on OXC metabolism and transport in Chinese epileptic patients using OXC as monotherapy and bitherapy with lamotrigine (LTG), levetiracetam (LEV), or valproic acid (VPA). Sixty-six Chinese epileptic patients were recruited from Xiangya Hospital Central South University, of whom 40 patients were receiving OXC monotherapy, 11 patients were placed in the OXC bitherapy group combined with one enzyme-inducing anti-epileptic drugs (LTG or LEV), and 15 patients were placed in the OXC bitherapy group combined with VPA. Oxcarbazepine and its main metabolite 10-hydrocarbazepine (MHD) plasma concentrations were measured using high performance liquid chromatography (HPLC)-UV method. In addition, eight single nucleotide polymorphisms (SNPs) in CYP3A4, CYP3A5, ABCB1 gene were genotyped by polymerase chain reaction-improved multiple ligase detection reaction (PCR-iMLDR). In the OXC+VPA group, ABCB1 rs2032582 and rs2032582-rs10234411-rs1045642 TAG haplotype were associated with MHD and MHD+OXC plasma concentration before permutation test. In OXC monotherapy and OXC+ LTG/LEV groups, no significant association between genetic polymorphisms in CYP3A4/5, ABCB1 gene and OXC plasma concentration parameters were observed. CYP3A4/5 and ABCB1 genetic variants might not take part in the metabolism and transport of MHD and OXC among epileptic patients using OXC monotherapy and bitherapy in combination with LEV, LTG or VPA.

MTHFR C677T polymorphism, homocysteine and B-vitamins status in a sample of Chinese and Malay subjects in Universiti Putra Malaysia.

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Choo, S C; Loh, S P; Khor, G L; Sabariah, M N; Rozita, R

2011-08-01

Methylenetetrahydrofolate reductase (MTHFR) C677T is involved in folate and homocysteine metabolism. Disruption in the activity of this enzyme will alter their levels in the body. This study assessed MTHFR C677T polymorphism and its relationship with serum homocysteine and B-vitamins levels in a sample of Chinese and Malays subjects in UPM, Serdang. One hundred subjects were randomly selected from among the university population. Folate, vitamin B12, B6, and homocysteine levels were determined using MBA, ECLIA, and HPLC, respectively. PCR coupled with HinfI digestion was used for detection of MTHFR C677T polymorphism. The frequency of T allele was higher in the Chinese subjects (0.40) compared to the Malay (0.14). Folate, vitamin B12 and B6 levels were highest in the wild genotype in both ethnic groups. Subjects with heterozygous and homozygous genotype showed the highest homocysteine levels. The serum folate and homocysteine were mainly affected by homozygous genotype. MTHFR C677T polymorphism plays an important role in influencing the folate and homocysteine metabolism.

Glutathione S-transferase gene polymorphisms in presbycusis.

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Ateş, Nurcan Aras; Unal, Murat; Tamer, Lülüfer; Derici, Ebru; Karakaş, Sevim; Ercan, Bahadir; Pata, Yavuz Selim; Akbaş, Yücel; Vayisoğlu, Yusuf; Camdeviren, Handan

2005-05-01

Glutathione and glutathione-related antioxidant enzymes are involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species. Reactive oxygen species generation occurs in prolonged relative hypoperfusion conditions such as in aging. The etiology of presbycusis is much less certain; however, a complex genetic cause is most likely. The effect of aging shows a wide interindividual range; we aimed to investigate whether profiles of (glutathione S-transferase (GST) M1, T1 and P1 genotypes may be associated with the risk of age-related hearing loss. We examined 68 adults with presbycusis and 69 healthy controls. DNA was extracted from whole blood, and the GSTM1, GSTT1 and GSTP1 polymorphisms were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler Instrument. Associations between specific genotypes and the development of presbycusis were examined by use of logistic regression analyses to calculate odds ratios and 95% confidence intervals. Gene polymorphisms at GSTM1, GSTT1, and GSTP1 in subjects with presbycusis were not significantly different than in the controls (p > 0.05). Also, the combinations of different GSTM1, GSTT1, and GSTP1 genotypes were not an increased risk of presbycusis (p > 0.05). We could not demonstrate any significant association between the GSTM1, GSTT1, and GSTP1 polymorphism and age-related hearing loss in this population. This may be because of our sample size, and further studies need to investigate the exact role of GST gene polymorphisms in the etiopathogenesis of the presbycusis.

Relationship between the murine Ah locus and 2,3,7,8-tetrachlorodibenzo-p-dioxin hepatic metabolism, enzyme induction, and toxicity

International Nuclear Information System (INIS)

Shen, E.S.

1988-01-01

The influence of the Ah locus and hepatic microsomal enzyme induction on 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) metabolism and hepatotoxicity was investigated using C57BL/6J (C57) and DBA/2J (DBA) mice. C57 mice are more sensitive to toxic and enzyme inductive effects of 2,3,7,8-TCDD than DBA mice. Characterization of interstrain differences in hepatic enzyme induction, 2,3,7,8-TCDD metabolism, and hepatotoxicity may aid in identifying the mechanism(s) of 2,3,7,8-TCDD toxicity. The hepatic uptake and metabolism of [ 14 C]2,3,7,8-TCDD were studied using isolated hepatocytes from control and 2,3,7,8-TCDD-pretreated C57 and DBA mice. Pretreated mice were injected with 2,3,7,8-TCDD at doses that maximally induce aryl hydrocarbon hydroxylase activity or at doses that approach the LD 50 value. Despite the induction of hepatic 7-ethoxyresorufin O-deethylase activity and benzo[a]pyrene metabolism, all 2,3,7,8-TCDD pretreatment doses failed to increase the rate of [ 14 C]2,3,7,8-TCDD metabolism for both C57 and DBA mice. These results suggest that the uptake and rate of hepatic metabolism of 2,3,7,8-TCDD do not correlate with genetic differences at the murine Ah locus

Adapting capillary gel electrophoresis as a sensitive, high-throughput method to accelerate characterization of nucleic acid metabolic enzymes.

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Greenough, Lucia; Schermerhorn, Kelly M; Mazzola, Laurie; Bybee, Joanna; Rivizzigno, Danielle; Cantin, Elizabeth; Slatko, Barton E; Gardner, Andrew F

2016-01-29

Detailed biochemical characterization of nucleic acid enzymes is fundamental to understanding nucleic acid metabolism, genome replication and repair. We report the development of a rapid, high-throughput fluorescence capillary gel electrophoresis method as an alternative to traditional polyacrylamide gel electrophoresis to characterize nucleic acid metabolic enzymes. The principles of assay design described here can be applied to nearly any enzyme system that acts on a fluorescently labeled oligonucleotide substrate. Herein, we describe several assays using this core capillary gel electrophoresis methodology to accelerate study of nucleic acid enzymes. First, assays were designed to examine DNA polymerase activities including nucleotide incorporation kinetics, strand displacement synthesis and 3'-5' exonuclease activity. Next, DNA repair activities of DNA ligase, flap endonuclease and RNase H2 were monitored. In addition, a multicolor assay that uses four different fluorescently labeled substrates in a single reaction was implemented to characterize GAN nuclease specificity. Finally, a dual-color fluorescence assay to monitor coupled enzyme reactions during Okazaki fragment maturation is described. These assays serve as a template to guide further technical development for enzyme characterization or nucleoside and non-nucleoside inhibitor screening in a high-throughput manner. © The Author(s) 2015. Published by Oxford University Press on behalf of Nucleic Acids Research.

Novel approach of molecular genetic understanding of iridology: relationship between iris constitution and angiotensin converting enzyme gene polymorphism.

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Um, Jae-Young; An, Nyeon-Hyoung; Yang, Gui-Bi; Lee, Geon-Mok; Cho, Ju-Jang; Cho, Jae-Woon; Hwang, Woo-Jun; Chae, Han-Jung; Kim, Hyung-Ryong; Hong, Seung-Heon; Kim, Hyung-Min

2005-01-01

Iridology is the study of the iris of the eye to detect the conditions of the body and its organs, genetic strengths and weaknesses, etc. Although iridology is not widely used as a scientific tool for healthcare professionals to get to the source of people's health conditions, it has been used as a supplementary source to help the diagnosis of medical conditions by noting irregularities of the pigmentation in the iris among some Korean Oriental medical doctors. Angiotensin converting enzyme (ACE) gene polymorphism is one of the most well studied genetic markers of vascular disease. We investigated the relationship between iridological constitution and ACE polymorphism in hypertensives. We classified 87 hypertensives and 79 controls according to iris constitution and determined the ACE genotype of each individual. DD genotype was more prevalent in patients with a neurogenic constitution than in controls. This finding supports the hypothesis that D allele is a candidate gene for hypertension and demonstrates the association among ACE genotype, Korean hypertensives and iris constitution.

The influence of a polymorphism in the gene encoding angiotensin converting enzyme (ACE on treatment outcomes in late-onset Pompe patients receiving alglucosidase alfa

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Rena C. Baek

2016-09-01

Full Text Available Correlations between angiotensin-converting enzyme (ACE genotype (I/I, I/D, D/D, disease severity at baseline and response to enzyme replacement therapy (ERT were assessed in the Pompe disease Late-Onset Treatment Study (LOTS. No correlations were observed between ACE genotype and disease severity at baseline. However, D/D patients appeared to have a reduced response to alglucosidase alfa treatment than I/I or I/D patients, suggesting that ACE polymorphisms may influence the response to alglucosidase alfa treatment and warrants further investigation.

Enzymes of yeast polyphosphate metabolism: structure, enzymology and biological roles.

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Gerasimaitė, Rūta; Mayer, Andreas

2016-02-01

Inorganic polyphosphate (polyP) is found in all living organisms. The known polyP functions in eukaryotes range from osmoregulation and virulence in parasitic protozoa to modulating blood coagulation, inflammation, bone mineralization and cellular signalling in mammals. However mechanisms of regulation and even the identity of involved proteins in many cases remain obscure. Most of the insights obtained so far stem from studies in the yeast Saccharomyces cerevisiae. Here, we provide a short overview of the properties and functions of known yeast polyP metabolism enzymes and discuss future directions for polyP research. © 2016 Authors; published by Portland Press Limited.

Angiotensin-Converting Enzyme (ACE) I/D and Alpha-Adducin (ADD1) G460W Gene Polymorphisms in Turkish Patients with Severe Chronic Tinnitus.

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Yuce, Salim; Sancakdar, Enver; Bağcı, Gokhan; Koc, Sema; Kurtulgan, Hande Kucuk; Bağcı, Binnur; Doğan, Mansur; Uysal, İsmail Onder

2016-04-01

Tinnitus is described as a disturbing sound sensation in the absence of external stimulation. We aimed to investigate whether there is any relationship between severe chronic tinnitus and angiotensin-converting enzyme (ACE) I/D and α-adducin (ADD1) G460W gene polymorphisms. The patient group and control group consisted of 89 and 104 individuals, respectively. The evaluation of tinnitus was performed using the Strukturiertes Tinnitus-Interview (STI). The Tinnitus Handicap Inventory (THI) was used to evaluate the tinnitus severity. Polymerase chain reaction (PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) techniques were used for genotyping. With regard to the ACE I/D polymorphism, there was no significant difference in genotype and allele frequencies between the patient group and control group. However, a statistically significant difference was found in genotype (pgene polymorphism. Combined genotype analysis showed that the ACE II /ADD1 GW genotype was statistically significantly higher in the patient group than in the control group (X2: 7.15, p=0.007). The odds ratio value of the GW genotype was 2.5 (95% CI=1.4-4.7) (pgene polymorphism and susceptibility to severe chronic tinnitus. It was found that the GW genotype increased the disease risk by 2.5-fold compared with other genotypes. This indicates that ADD1 G460W polymorphism could be an important factor in the pathophysiology of tinnitus.

Subcellular localization of glycolytic enzymes and characterization of intermediary metabolism of Trypanosoma rangeli.

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Rondón-Mercado, Rocío; Acosta, Héctor; Cáceres, Ana J; Quiñones, Wilfredo; Concepción, Juan Luis

2017-09-01

Trypanosoma rangeli is a hemoflagellate protist that infects wild and domestic mammals as well as humans in Central and South America. Although this parasite is not pathogenic for human, it is being studied because it shares with Trypanosoma cruzi, the etiological agent of Chagas' disease, biological characteristics, geographic distribution, vectors and vertebrate hosts. Several metabolic studies have been performed with T. cruzi epimastigotes, however little is known about the metabolism of T. rangeli. In this work we present the subcellular distribution of the T. rangeli enzymes responsible for the conversion of glucose to pyruvate, as determined by epifluorescense immunomicroscopy and subcellular fractionation involving either selective membrane permeabilization with digitonin or differential and isopycnic centrifugation. We found that in T. rangeli epimastigotes the first six enzymes of the glycolytic pathway, involved in the conversion of glucose to 1,3-bisphosphoglycerate are located within glycosomes, while the last four steps occur in the cytosol. In contrast with T. cruzi, where three isoenzymes (one cytosolic and two glycosomal) of phosphoglycerate kinase are expressed simultaneously, only one enzyme with this activity is detected in T. rangeli epimastigotes, in the cytosol. Consistent with this latter result, we found enzymes involved in auxiliary pathways to glycolysis needed to maintain adenine nucleotide and redox balances within glycosomes such as phosphoenolpyruvate carboxykinase, malate dehydrogenase, fumarate reductase, pyruvate phosphate dikinase and glycerol-3-phosphate dehydrogenase. Glucokinase, galactokinase and the first enzyme of the pentose-phosphate pathway, glucose-6-phosphate dehydrogenase, were also located inside glycosomes. Furthermore, we demonstrate that T. rangeli epimastigotes growing in LIT medium only consume glucose and do not excrete ammonium; moreover, they are unable to survive in partially-depleted glucose medium. The

The mouse liver displays daily rhythms in the metabolism of phospholipids and in the activity of lipid synthesizing enzymes.

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Gorné, Lucas D; Acosta-Rodríguez, Victoria A; Pasquaré, Susana J; Salvador, Gabriela A; Giusto, Norma M; Guido, Mario Eduardo

2015-02-01

The circadian system involves central and peripheral oscillators regulating temporally biochemical processes including lipid metabolism; their disruption leads to severe metabolic diseases (obesity, diabetes, etc). Here, we investigated the temporal regulation of glycerophospholipid (GPL) synthesis in mouse liver, a well-known peripheral oscillator. Mice were synchronized to a 12:12 h light-dark (LD) cycle and then released to constant darkness with food ad libitum. Livers collected at different times exhibited a daily rhythmicity in some individual GPL content with highest levels during the subjective day. The activity of GPL-synthesizing/remodeling enzymes: phosphatidate phosphohydrolase 1 (PAP-1/lipin) and lysophospholipid acyltransferases (LPLATs) also displayed significant variations, with higher levels during the subjective day and at dusk. We evaluated the temporal regulation of expression and activity of phosphatidylcholine (PC) synthesizing enzymes. PC is mainly synthesized through the Kennedy pathway with Choline Kinase (ChoK) as a key regulatory enzyme or through the phosphatidylethanolamine (PE) N-methyltransferase (PEMT) pathway. The PC/PE content ratio exhibited a daily variation with lowest levels at night, while ChoKα and PEMT mRNA expression displayed maximal levels at nocturnal phases. Our results demonstrate that mouse liver GPL metabolism oscillates rhythmically with a precise temporal control in the expression and/or activity of specific enzymes.

Sucrose-Metabolizing Enzymes in Transport Tissues and Adjacent Sink Structures in Developing Citrus Fruit 1

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Lowell, Cadance A.; Tomlinson, Patricia T.; Koch, Karen E.

1989-01-01

Juice tissues of citrus lack phloem; therefore, photosynthates enroute to juice sacs exit the vascular system on the surface of each segment. Areas of extensive phloem unloading and transport (vascular bundles + segment epidermis) can thus be separated from those of assimilate storage (juice sacs) and adjacent tissues where both processes occur (peel). Sugar composition, dry weight accumulation, and activities of four sucrose-metabolizing enzymes (soluble and cell-wall-bound acid invertase, alkaline invertase, sucrose synthase, and sucrose phosphate synthase) were measured in these transport and sink tissues of grapefruit (Citrus paradisi Macf.) to determine more clearly whether a given enzyme appeared to be more directly associated with assimilate transport versus deposition or utilization. Results were compared at three developmental stages. Activity of sucrose (per gram fresh weight and per milligram protein) extracted from zones of extensive phloem unloading and transport was significantly greater than from adjacent sink tissues during the stages (II and III) when juice sacs grow most rapidly. In stage II fruit, activity of sucrose synthase also significantly surpassed that of all other sucrose-metabolizing enzymes in extracts from the transport tissues (vascular bundles + segment epidermis). In contrast, sucrose phosphate synthase and alkaline invertase at this stage of growth were the most active enzymes from adjacent, rapidly growing, phloem-free sink tissues (juice sacs). Activity of these two enzymes in extracts from juice sacs was significantly greater than that form the transport tissues (vascular bundles + segment epidermis). Soluble acid invertase was the most active enzyme in extracts from all tissues of very young fruit (stage I), including nonvascular regions, but nearly disappeared prior to the onset of juice sac sugar accumulation. The physiological function of high sucrose synthase activity in the transport tissues during rapid sucrose import

Angiotensinogen Polymorphisms and Post-Transplantation Diabetes Mellitus in Korean Renal Transplant Subjects

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Sul ra Lee

2013-03-01

Full Text Available Background: Post-transplant diabetes mellitus (PTDM is a common and serious metabolic complication. Genetic polymorphisms of angiotensin-converting enzyme (ACE and angiotensinogen (AGT genes have been reported to be related to diabetes mellitus and insulin sensitivity; however, the role of these genes in the development of PTDM is not known. For this purpose, we investigated the association of ACE and AGT genetic polymorphisms with PTDM. Methods: A total of 302 subjects without previously diagnosed diabetes who had received kidney transplants were included. One ACE single nucleotide polymorphism (SNP (rs4291 and two AGT SNPs (rs 699 and rs 4762 were genotyped from genomic DNA with direct sequencing. Results: PTDM developed in 49 (16.2% of 302 subjects. Subjects in the PTDM were older than those in the non-PTDM. There was a significant difference between the two groups in tacrolimus use (p=0.03. Of the three SNPs, the rs4762 of the AGT gene was significantly associated with the development of PTDM in the dominant models (p = 0.03 after adjusting for age and tacrolimus usage. Conclusions: AGT gene rs4762 polymorphisms may serve as genetic markers for the development of PTDM. The exact molecular mechanisms still need to be clarified.

Interference of aldehyde metabolizing enzyme with diamine oxidase/histaminase/activity as determined by 14C putrescine method

International Nuclear Information System (INIS)

Fogel, W.A.; Bieganski, T.; Wozniak, J.; Maslinski, C.

1978-01-01

The Δ 1 pyrroline formation, as an indicator of diamine oxidase activity according to Okuyama and Kobayashi 14 C putrescine test (1961, Archs Biochem. Biophys., vol.95, 242), has been investigated in several tissue homogenates. When guinea pig liver homogenate was used as a source of enzyme in the presence of aldehyde dehydrogenase inhibitors chlorate hydrate and acetaldehyde the level of formation Δ 1 pyrroline was strongly increased in a dose-dependent manner. Also inhibition of aldehyde reductase by phenobarbital enhanced Δ 1 pyrroline formation, but to a lesser degree. In other tissues, with very high initial diamine oxidase activity (rat intestine, dog kidney) or with very low diamine oxidase activity (guinea pig skin, dog liver) the influence of these inhibitors was only slight. Pyrazole, an inhibitor of alcohol dehydrogenase exerted only a small effect on Δ 1 pyrroline formation. All aldehyde-metabolizing enzymes inhibitors, except pyrazole, were without effect on purified pea seddling and hog kidney diamine oxidases. The use of aldehyde-metabolizing enzymes inhibitors may help to reveal the real values of diamine oxidase activity, when tissues homogenates are used as a source of enzyme. (author)

Biotransformation enzymes for xenobiotics and personalization of treatment regimens for tuberculosis patients

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G. N. Mozhokina

2016-01-01

Full Text Available The article presents the analysis of the literature on specific metabolism of anti-tuberculosis drugs depending on polymorphism of genes controlling synthesis and action of biotransformation enzymes, in particular cytochrome P-450 isozymes and enzymes of the IInd phase of biotransformation (N-acetyltransferase, glutathione S-transferase respective adverse reactions development, first of  all hepatotoxic ones. The  possibility of pharmacogenetic studies with the evaluation of genetic predisposition to developing adverse reactions to medications has been discussed in respect of personalized approach to effective and safe treatment of tuberculosis patients.

The genes and enzymes of sucrose metabolism in moderately thermophilic methanotroph Methylocaldum szegediense O12.

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But, Sergey Y; Solntseva, Natalia P; Egorova, Svetlana V; Mustakhimov, Ildar I; Khmelenina, Valentina N; Reshetnikov, Alexander; Trotsenko, Yuri A

2018-05-01

Four enzymes involved in sucrose metabolism: sucrose phosphate synthase (Sps), sucrose phosphate phosphatase (Spp), sucrose synthase (Sus) and fructokinase (FruK), were obtained as his-tagged proteins from the moderately thermophilic methanotroph Methylocaldum szegediense O12. Sps, Spp, FruK and Sus demonstrated biochemical properties similar to those of other bacterial counterparts, but the translated amino acid sequences of Sps and Spp displayed high divergence from the respective microbial enzymes. The Sus of M. szegediense O12 catalyzed the reversible reaction of sucrose cleavage in the presence of ADP or UDP and preferred ADP as a substrate, thus implying a connection between sucrose and glycogen metabolism. Sus-like genes were found only in a few methanotrophs, whereas amylosucrase was generally used in sucrose cleavage in this group of bacteria. Like other microbial fructokinases, FruK of M. szegediense O12 showed a high specificity to fructose.

Effect of angiotensin-converting enzyme gene polymorphism at the results of losartan use in the patients with type 2 diabetes mellitus

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T. Yu. Poniatowskaya

2015-03-01

Odessa National Medical University   Summary The article presented is an original investigation where the effects of losartan in patients with hypertension and type 2 diabetes mellitus (T2DM have been evaluated. The effect of therapy has been estimated with the help of gene ACE allelic variant. The dependence of enalapril antihypertensive action and nephroprotective action of ACE polymorphism has been revealed. The results obtained show a different effect on ACE allele variants of lipid metabolism in patients with hypertension and T2DM and complications in the form of hypertriglyceridemia in the patients with DD-genotype.   Key words: type 2 diabetes mellitus, hypertension, I / D polymorphism of the gene ACE, pharmacogenetics, losartan.

Influence of the A3669G Glucocorticoid Receptor Gene Polymorphism on the Metabolic Profile of Pediatric Patients with Congenital Adrenal Hyperplasia

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Ricardo P. P. Moreira

2014-01-01

Full Text Available Background. Pediatric CAH patients have an increased risk of cardiovascular disease, and it remains unknown if genetic predisposition is a contributing factor. Glucocorticoid receptor gene (NR3C1 polymorphisms are associated with an adverse metabolic profile. Our aim was to analyze the association between the NR3C1 polymorphisms and the metabolic profile of pediatric CAH patients. Methods. Forty-one patients (26SW/15SV received glucocorticoid (GC replacement therapy to achieve normal androgen levels. Obesity was defined by BMI≥95th percentile. NR3C1 alleles were genotyped, and association analyses with phenotype were done with Chi-square, t-test, and multivariate and regression analysis. Results. Obesity was observed in 31.7% of patients and was not correlated with GC doses and treatment duration. Z-score BMI was positively correlated with blood pressure, triglycerides, LDL-c levels, and HOMA-IR. NR3C1 polymorphisms, BclI and A3669G, were found in 23.1% and 9.7% of alleles, respectively. A3669G carriers presented higher LDL-c levels compared to wild-type subjects. BclI-carriers and noncarriers did not differ. Conclusion. Our results suggest that A3669G-polymorphism could be involved with a susceptibility to adverse lipid profile in pediatric CAH patients. This study provides new insight into the GR screening during CAH treatment, which could help to identify the subgroup of at-risk patients who would most benefit from preventive therapeutic action.

Metabolism of citral, the major constituent of lemongrass oil, in the cabbage looper, Trichoplusia ni, and effects of enzyme inhibitors on toxicity and metabolism.

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Tak, Jun-Hyung; Isman, Murray B

2016-10-01

Although screening for new and reliable sources of botanical insecticides remains important, finding ways to improve the efficacy of those already in use through better understanding of their modes-of-action or metabolic pathways, or by improving formulations, deserves greater attention as the latter may present lesser regulation hurdles. Metabolic processing of citral (a combination of the stereoisomers geranial and neral), a main constituent of lemongrass (Cymbopogon citratus) essential oil has not been previously examined in insects. To address this, we investigated insecticidal activities of lemongrass oil and citral, as well as the metabolism of citral in larvae of the cabbage looper, Trichoplusia ni, in associations with well-known enzyme inhibitors. Among the inhibitors tested, piperonyl butoxide showed the highest increase in toxicity followed by triphenyl phosphate, but no synergistic interaction between the inhibitors was observed. Topical application of citral to fifth instar larvae produced mild reductions in food consumption, and frass analysis after 24h revealed geranic acid (99.7%) and neric acid (98.8%) as major metabolites of citral. Neither citral nor any other metabolites were found following in vivo analysis of larvae after 24h, and no significant effect of enzyme inhibitors was observed on diet consumption or citral metabolism. Copyright © 2016 Elsevier B.V. All rights reserved.

Anaerobic 4-hydroxyproline utilization: Discovery of a new glycyl radical enzyme in the human gut microbiome uncovers a widespread microbial metabolic activity.

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Huang, Yolanda Y; Martínez-Del Campo, Ana; Balskus, Emily P

2018-02-06

The discovery of enzymes responsible for previously unappreciated microbial metabolic pathways furthers our understanding of host-microbe and microbe-microbe interactions. We recently identified and characterized a new gut microbial glycyl radical enzyme (GRE) responsible for anaerobic metabolism of trans-4-hydroxy-l-proline (Hyp). Hyp dehydratase (HypD) catalyzes the removal of water from Hyp to generate Δ 1 -pyrroline-5-carboxylate (P5C). This enzyme is encoded in the genomes of a diverse set of gut anaerobes and is prevalent and abundant in healthy human stool metagenomes. Here, we discuss the roles HypD may play in different microbial metabolic pathways as well as the potential implications of this activity for colonization resistance and pathogenesis within the human gut. Finally, we present evidence of anaerobic Hyp metabolism in sediments through enrichment culturing of Hyp-degrading bacteria, highlighting the wide distribution of this pathway in anoxic environments beyond the human gut.

Selection Finder (SelFi: A computational metabolic engineering tool to enable directed evolution of enzymes

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Neda Hassanpour

2017-06-01

Full Text Available Directed evolution of enzymes consists of an iterative process of creating mutant libraries and choosing desired phenotypes through screening or selection until the enzymatic activity reaches a desired goal. The biggest challenge in directed enzyme evolution is identifying high-throughput screens or selections to isolate the variant(s with the desired property. We present in this paper a computational metabolic engineering framework, Selection Finder (SelFi, to construct a selection pathway from a desired enzymatic product to a cellular host and to couple the pathway with cell survival. We applied SelFi to construct selection pathways for four enzymes and their desired enzymatic products xylitol, D-ribulose-1,5-bisphosphate, methanol, and aniline. Two of the selection pathways identified by SelFi were previously experimentally validated for engineering Xylose Reductase and RuBisCO. Importantly, SelFi advances directed evolution of enzymes as there is currently no known generalized strategies or computational techniques for identifying high-throughput selections for engineering enzymes.

Glu504Lys Single Nucleotide Polymorphism of Aldehyde Dehydrogenase 2 Gene and the Risk of Human Diseases

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Yan Zhao

2015-01-01

Full Text Available Aldehyde dehydrogenase (ALDH 2 is a mitochondrial enzyme that is known for its important role in oxidation and detoxification of ethanol metabolite acetaldehyde. ALDH2 also metabolizes other reactive aldehydes such as 4-hydroxy-2-nonenal and acrolein. The Glu504Lys single nucleotide polymorphism (SNP of ALDH2 gene, which is found in approximately 40% of the East Asian populations, causes defect in the enzyme activity of ALDH2, leading to alterations in acetaldehyde metabolism and alcohol-induced “flushing” syndrome. Evidence suggests that ALDH2 Glu504Lys SNP is a potential candidate genetic risk factor for a variety of chronic diseases such as cardiovascular disease, cancer, and late-onset Alzheimer’s disease. In addition, the association between ALDH2 Glu504Lys SNP and the development of these chronic diseases appears to be affected by the interaction between the SNP and lifestyle factors such as alcohol consumption as well as by the presence of other genetic variations.

Association of angiotensin-converting enzyme (ACE) gene polymorphism with elevated serum ACE activity and major depression in an Iranian population.

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Firouzabadi, Negar; Shafiei, Massoumeh; Bahramali, Ehsan; Ebrahimi, Soltan Ahmed; Bakhshandeh, Hooman; Tajik, Nader

2012-12-30

Genetic factors contribute substantially to the likelihood of developing major depressive disorder (MDD). The importance of renin-angiotensin system (RAS) elements in cognition and behaviour and their involvement in aetiology and treatment of depression imply that RAS gene polymorphism(s) associated with RAS overactivity might also be associated with depression. In the present study, genotype and allele frequencies of six common polymorphisms of genes encoding for RAS components were determined in DNAs extracted from venous blood of 191 depressed and 104 healthy individuals using polymerase chain reaction (PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and serum angiotensin-converting enzyme (ACE) activity was assayed using a high-performance liquid chromatography (HPLC) method. The results showed, for the first time, that GG genotype of ACE A2350G was significantly associated with MDD among Iranian participants (P=0.001; odds ratio (OR)=6.2; 95% confidence interval (CI)=2.1-18.3). Significant higher serum ACE activity (P=0.0001) as well as higher diastolic blood pressure (P=0.036) were observed in depressed patients compared to the healthy control group. Depressed patients carrying GG genotype of the A2350G polymorphism had a significantly higher serum ACE activity (P=0.02) than individuals with either AA or AG genotype. In conclusion, this study supports the hypothesis of RAS overactivity in depression in that the genotype associated with higher serum ACE activity in an Iranian population was also associated with MDD. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

Discovery of new enzymes and metabolic pathways using structure and genome context

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Zhao, Suwen; Kumar, Ritesh; Sakai, Ayano; Vetting, Matthew W.; Wood, B. McKay; Brown, Shoshana; Bonanno, Jeffery B.; Hillerich, Brandan S.; Seidel, Ronald D.; Babbitt, Patricia C.; Almo, Steven C.; Sweedler, Jonathan V.; Gerlt, John A.; Cronan, John E.; Jacobson, Matthew P.

2014-01-01

Assigning valid functions to proteins identified in genome projects is challenging, with over-prediction and database annotation errors major concerns1. We, and others2, are developing computation-guided strategies for functional discovery using “metabolite docking” to experimentally derived3 or homology-based4 three-dimensional structures. Bacterial metabolic pathways often are encoded by “genome neighborhoods” (gene clusters and/or operons), which can provide important clues for functional assignment. We recently demonstrated the synergy of docking and pathway context by “predicting” the intermediates in the glycolytic pathway in E. coli5. Metabolite docking to multiple binding proteins/enzymes in the same pathway increases the reliability of in silico predictions of substrate specificities because the pathway intermediates are structurally similar. We report that structure-guided approaches for predicting the substrate specificities of several enzymes encoded by a bacterial gene cluster allowed i) the correct prediction of the in vitro activity of a structurally characterized enzyme of unknown function (PDB 2PMQ), 2-epimerization of trans-4-hydroxy-L-proline betaine (tHyp-B) and cis-4-hydroxy-D-proline betaine (cHyp-B), and ii) the correct identification of the catabolic pathway in which Hyp-B 2-epimerase participates. The substrate-liganded pose predicted by virtual library screening (docking) was confirmed experimentally. The enzymatic activities in the predicted pathway were confirmed by in vitro assays and genetic analyses; the intermediates were identified by metabolomics; and repression of the genes encoding the pathway by high salt was established by transcriptomics, confirming the osmolyte role of tHyp-B. This study establishes the utility of structure-guide functional predictions to enable the discovery of new metabolic pathways. PMID:24056934

Electrical stimulation affects metabolic enzyme phosphorylation, protease activation and meat tenderization in beef

DEFF Research Database (Denmark)

Li, C.B.; Li, J.; Zhou, G.H.

2012-01-01

The objective of this study was to investigate the response of sarcoplasmic proteins in bovine longissimus muscle to low-voltage electrical stimulation (ES, 80 V, 35 s) after dressing and its contribution to meat tenderization at early postmortem time. Proteome analysis showed that ES resulted...... muscles up to 24 h. Immunohistochemistry and transmission electron microscopy further indicated that lysosomal enzymes were released at early postmortem time. ES also induced ultrastructural disruption of sarcomeres. In addition, ES accelerated (P ..., as well as pH decline and more preferred pH/temperature decline mode. Finally, ES accelerated meat tenderization with lower (P time. A possible relationship was suggested between change in phosphorylation level of energy metabolic enzymes and postmortem...

Promiscuous activities of heterologous enzymes lead to unintended metabolic rerouting in Saccharomyces cerevisiae engineered to assimilate various sugars from renewable biomass.

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Yun, Eun Ju; Oh, Eun Joong; Liu, Jing-Jing; Yu, Sora; Kim, Dong Hyun; Kwak, Suryang; Kim, Kyoung Heon; Jin, Yong-Su

2018-01-01

Understanding the global metabolic network, significantly perturbed upon promiscuous activities of foreign enzymes and different carbon sources, is crucial for systematic optimization of metabolic engineering of yeast Saccharomyces cerevisiae . Here, we studied the effects of promiscuous activities of overexpressed enzymes encoded by foreign genes on rerouting of metabolic fluxes of an engineered yeast capable of assimilating sugars from renewable biomass by profiling intracellular and extracellular metabolites. Unbiased metabolite profiling of the engineered S. cerevisiae strain EJ4 revealed promiscuous enzymatic activities of xylose reductase and xylitol dehydrogenase on galactose and galactitol, respectively, resulting in accumulation of galactitol and tagatose during galactose fermentation. Moreover, during glucose fermentation, a trisaccharide consisting of glucose accumulated outside of the cells probably owing to the promiscuous and transglycosylation activity of β-glucosidase expressed for hydrolyzing cellobiose. Meanwhile, higher accumulation of fatty acids and secondary metabolites was observed during xylose and cellobiose fermentations, respectively. The heterologous enzymes functionally expressed in S. cerevisiae showed promiscuous activities that led to unintended metabolic rerouting in strain EJ4. Such metabolic rerouting could result in a low yield and productivity of a final product due to the formation of unexpected metabolites. Furthermore, the global metabolic network can be significantly regulated by carbon sources, thus yielding different patterns of metabolite production. This metabolomic study can provide useful information for yeast strain improvement and systematic optimization of yeast metabolism to manufacture bio-based products.

CYP1B1 gene polymorphisms correlate with an increased risk of urinary bladder cancer in India.

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Sankhwar, Monica; Sankhwar, Satya Narayan; Abhishek, Amar; Gupta, Nishi; Rajender, Singh

2016-04-01

The urinary bladder is the target of several toxic compounds, which makes the bladder more prone to cancer. Cytochrome P450 1B1 enzyme is present in tumor tissues and metabolizes the polyaromatic carcinogens and activates several procarcinogens that cause DNA damage. We examined the functional single-nucleotide polymorphisms in the CYP1B1 gene to study their association with the urinary bladder cancer. We recruited 234 cases of pure urothelial and 258 bladder cancer-free control samples from the individuals visiting the clinic for various investigations. We genotyped 4 CYP1B1 single-nucleotide polymorphisms using the polymerase chain reaction-restriction fragment length polymorphism analysis. The genotype data were analyzed by the Chi-square test. Haplotypes were constructed to evaluate the joint effect of the 4 polymorphisms. Overall, 3 polymorphisms-rs10012, rs150799650, and rs1056827 (odds ratio [OR] = 2.34, CI: 1.59-3.45, Pbladder cancer. Haplotype analysis suggested GTTC, GTTG, and ATGC to be the risk factors for bladder cancer. Overall, 3 polymorphisms, rs10012, rs1056827, and rs150799650 in the CYP1B1 gene correlate with urinary bladder cancer significantly in the Indo-European population of Uttar Pradesh, India. Further investigations in other populations are advised. Copyright © 2016 Elsevier Inc. All rights reserved.

Xenobiotica-metabolizing enzymes in the skin of rat, mouse, pig, guinea pig, man, and in human skin models.

Science.gov (United States)

Oesch, F; Fabian, E; Landsiedel, Robert

2018-06-18

Studies on the metabolic fate of medical drugs, skin care products, cosmetics and other chemicals intentionally or accidently applied to the human skin have become increasingly important in order to ascertain pharmacological effectiveness and to avoid toxicities. The use of freshly excised human skin for experimental investigations meets with ethical and practical limitations. Hence information on xenobiotic-metabolizing enzymes (XME) in the experimental systems available for pertinent studies compared with native human skin has become crucial. This review collects available information of which-taken with great caution because of the still very limited data-the most salient points are: in the skin of all animal species and skin-derived in vitro systems considered in this review cytochrome P450 (CYP)-dependent monooxygenase activities (largely responsible for initiating xenobiotica metabolism in the organ which provides most of the xenobiotica metabolism of the mammalian organism, the liver) are very low to undetectable. Quite likely other oxidative enzymes [e.g. flavin monooxygenase, COX (cooxidation by prostaglandin synthase)] will turn out to be much more important for the oxidative xenobiotic metabolism in the skin. Moreover, conjugating enzyme activities such as glutathione transferases and glucuronosyltransferases are much higher than the oxidative CYP activities. Since these conjugating enzymes are predominantly detoxifying, the skin appears to be predominantly protected against CYP-generated reactive metabolites. The following recommendations for the use of experimental animal species or human skin in vitro models may tentatively be derived from the information available to date: for dermal absorption and for skin irritation esterase activity is of special importance which in pig skin, some human cell lines and reconstructed skin models appears reasonably close to native human skin. With respect to genotoxicity and sensitization reactive

PAH-DNA adducts in environmentally exposed population in relation to metabolic and DNA repair gene polymorphisms

International Nuclear Information System (INIS)

Binkova, Blanka; Chvatalova, Irena; Lnenickova, Zdena; Milcova, Alena; Tulupova, Elena; Farmer, Peter B.; Sram, Radim J.

2007-01-01

Epidemiologic studies indicate that prolonged exposure to particulate air pollution may be associated with increased risk of cardiovascular diseases and cancer in general population. These effects may be attributable to polycyclic aromatic hydrocarbons (PAHs) adsorbed to respirable air particles. It is expected that metabolic and DNA repair gene polymorphisms may modulate individual susceptibility to PAH exposure. This study investigates relationships between exposure to PAHs, polymorphisms of these genes and DNA adducts in group of occupationally exposed policemen (EXP, N = 53, males, aged 22-50 years) working outdoors in the downtown area of Prague and in matched 'unexposed' controls (CON, N = 52). Personal exposure to eight carcinogenic PAHs (c-PAHs) was evaluated by personal samplers during working shift prior to collection of biological samples. Bulky-aromatic DNA adducts were analyzed in lymphocytes by 32 P-postlabeling assay. Polymorphisms of metabolizing (GSTM1, GSTP1, GSTT1, EPHX1, CYP1A1-MspI) and DNA repair (XRCC1, XPD) genes were determined by PCR-based RFLP assays. As potential modifiers and/or cofounders, urinary cotinine levels were analyzed by radioimmunoassay, plasma levels of vitamins A, C, E and folates by HPLC, cholesterol and triglycerides using commercial kits. During the sampling period ambient particulate air pollution was as follows: PM10 32-55 μg/m 3 , PM2.5 27-38 μg/m 3 , c-PAHs 18-22 ng/m 3 ; personal exposure to c-PAHs: 9.7 ng/m 3 versus 5.8 ng/m 3 (P 8 nucleotides versus 0.82 ± 0.23 adducts/10 8 nucleotides, P = 0.065), whereas the level of the B[a]P-'like' adduct was significantly higher in exposed group (0.122 ± 0.036 adducts/10 8 nucleotides versus 0.099 ± 0.035 adducts/10 8 nucleotides, P = 0.003). A significant difference in both the total (P < 0.05) and the B[a]P-'like' DNA adducts (P < 0.01) between smokers and nonsmokers within both groups was observed. A significant positive association between DNA adduct and cotinine

Polymorphisms in estrogen-metabolizing and estrogen receptor genes and the risk of developing breast cancer among a cohort of women with benign breast disease

International Nuclear Information System (INIS)

Gallicchio, Lisa; Berndt, Sonja I; McSorley, Meghan A; Newschaffer, Craig J; Thuita, Lucy W; Argani, Pedram; Hoffman, Sandra C; Helzlsouer, Kathy J

2006-01-01

A cohort study was conducted to examine the role of genetic polymorphisms in three estrogen metabolizing enzymes (COMT, CYP1A1, CYP1B1) and the two estrogen receptors (ESR1, ESR2) in the progression of benign breast disease (BBD) to breast cancer. Among participants in an ongoing cohort study, 1438 Caucasian women had a breast biopsy for BBD and were successfully genotyped for at least one of the polymorphisms examined in this study. Genotypes were determined using DNA extracted from blood specimens collected in 1989. Incident cases of breast cancer occurring subsequent to BBD diagnosis up to 2003 were identified through cancer registries. Among all participants, the ESR2 *5772G allele was associated with a significant decrease in the risk of breast cancer among women with BBD (Odds Ratio (OR) 0.38; 95% Confidence Interval (CI) 0.15, 0.96). Compared to the reference wild-type genotypes, marginally significant associations with the development of breast cancer were observed between carriers of the variant ESR1 – 104062T allele (OR 0.70, 95% CI 0.45, 1.09), the variant ESR2 *38A allele (OR 1.40; 95% CI 0.88, 2.25), and the variant CYP1B1 453Ser allele (OR 1.48, 95% CI 0.95, 2.32). The results indicate that specific polymorphisms in the CYP1B1, ESR1, and ESR2 genes may play a role in progression of BBD to breast cancer among Caucasian women. Although additional studies are needed to confirm or refute our findings, these results suggest that genetic markers may aid in the identification of women who are at risk for progression of BBD to cancer

Effects of Arctium lappa aqueous extract on lipid profile and hepatic enzyme levels of sucrose-induced metabolic syndrome in female rats

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Akram Ahangarpour

Full Text Available ABSTRACT Arctium lappa is known to have antioxidant and antidiabetic effects in traditional medicine. Objectives: The aim of this paper was to study the effects of A. lappa root extract (AE on lipid profile and hepatic enzyme levels in sucrose-induced metabolic syndrome (MS in female rats. The study used 40 adult female Wistar rats weighing 150 g-250 g randomly divided into five groups: control, metabolic syndrome (MS, metabolic syndrome+AE at 50,100, 200 mg/kg. MS was induced by administering 50% sucrose in drinking water for 6 weeks. AE was intra-peritoneally administered daily at doses of 50,100, and 200 mg/kg for two sequential weeks at the end of the fourth week in metabolic syndrome rats. Twenty-four hours after the last administration of AE, blood was collected and centrifuged, and then the serum was used for the measurement of lipid profile and hepatic enzyme. Serum glucose, insulin, fasting insulin resistance index, body weight, water intake, lipid profile, and hepatic enzymes were significantly increased although food intake was decreased in MS rats compared to the control rats. The lipids and liver enzymes were reduced by AE extracts in the MS group. This study showed that the A. lappa root aqueous extract exhibits a hypolipidemic activity of hyperlipidemic rats. This activity is practically that of a triple-impact antioxidant, hypolipidemic, and hepatoprotective.

Linking metabolic QTLs with network and cis-eQTLs controlling biosynthetic pathways.

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Adam M Wentzell

2007-09-01

Full Text Available Phenotypic variation between individuals of a species is often under quantitative genetic control. Genomic analysis of gene expression polymorphisms between individuals is rapidly gaining popularity as a way to query the underlying mechanistic causes of variation between individuals. However, there is little direct evidence of a linkage between global gene expression polymorphisms and phenotypic consequences. In this report, we have mapped quantitative trait loci (QTLs-controlling glucosinolate content in a population of 403 Arabidopsis Bay x Sha recombinant inbred lines, 211 of which were previously used to identify expression QTLs controlling the transcript levels of biosynthetic genes. In a comparative study, we have directly tested two plant biosynthetic pathways for association between polymorphisms controlling biosynthetic gene transcripts and the resulting metabolites within the Arabidopsis Bay x Sha recombinant inbred line population. In this analysis, all loci controlling expression variation also affected the accumulation of the resulting metabolites. In addition, epistasis was detected more frequently for metabolic traits compared to transcript traits, even when both traits showed similar distributions. An analysis of candidate genes for QTL-controlling networks of transcripts and metabolites suggested that the controlling factors are a mix of enzymes and regulatory factors. This analysis showed that regulatory connections can feedback from metabolism to transcripts. Surprisingly, the most likely major regulator of both transcript level for nearly the entire pathway and aliphatic glucosinolate accumulation is variation in the last enzyme in the biosynthetic pathway, AOP2. This suggests that natural variation in transcripts may significantly impact phenotypic variation, but that natural variation in metabolites or their enzymatic loci can feed back to affect the transcripts.

Alanine-glyoxylate aminotransferase 2 (AGXT2 polymorphisms have considerable impact on methylarginine and β-aminoisobutyrate metabolism in healthy volunteers.

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Anja Kittel

Full Text Available Elevated plasma concentrations of asymmetric (ADMA and symmetric (SDMA dimethylarginine have repeatedly been linked to adverse clinical outcomes. Both methylarginines are substrates of alanine-glyoxylate aminotransferase 2 (AGXT2. It was the aim of the present study to simultaneously investigate the functional relevance and relative contributions of common AGXT2 single nucleotide polymorphisms (SNPs to plasma and urinary concentrations of methylarginines as well as β-aminoisobutyrate (BAIB, a prototypic substrate of AGXT2. In a cohort of 400 healthy volunteers ADMA, SDMA and BAIB concentrations were determined in plasma and urine using HPLC-MS/MS and were related to the coding AGXT2 SNPs rs37369 (p.Val140Ile and rs16899974 (p.Val498Leu. Volunteers heterozygous or homozygous for the AGXT2 SNP rs37369 had higher SDMA plasma concentrations by 5% and 20% (p = 0.002 as well as higher BAIB concentrations by 54% and 146%, respectively, in plasma and 237% and 1661%, respectively, in urine (both p<0.001. ADMA concentrations were not affected by both SNPs. A haplotype analysis revealed that the second investigated AGXT2 SNP rs16899974, which was not significantly linked to the other AGXT2 SNP, further aggravates the effect of rs37369 with respect to BAIB concentrations in plasma and urine. To investigate the impact of the amino acid exchange p.Val140Ile, we established human embryonic kidney cell lines stably overexpressing wild-type or mutant (p.Val140Ile AGXT2 protein and assessed enzyme activity using BAIB and stable-isotope labeled [²H₆]-SDMA as substrate. In vitro, the amino acid exchange of the mutant protein resulted in a significantly lower enzyme activity compared to wild-type AGXT2 (p<0.05. In silico modeling of the SNPs indicated reduced enzyme stability and substrate binding. In conclusion, SNPs of AGXT2 affect plasma as well as urinary BAIB and SDMA concentrations linking methylarginine metabolism to the common genetic trait of hyper

Count on dopamine: influences of COMT polymorphisms on numerical cognition

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Annelise eJúlio-Costa

2013-08-01

Full Text Available Catechol-O-methyltransferase (COMT is an enzyme that is particularly important for the metabolism of dopamine. Functional polymorphisms of COMT have been implicated in working memory and numerical cognition. This is an exploratory study that aims at investigating associations between COMT polymorphisms, working memory and numerical cognition. Elementary school children from 2th to 6th grades were divided into two groups according to their COMT val158met polymorphism (homozygous for valine allele [n= 61] versus heterozygous plus methionine homozygous children or met+ group [n=94]. Both groups were matched for age and intelligence. Working memory was assessed through digit span and Corsi blocks. Symbolic numerical processing was assessed through transcoding and single-digit word problem tasks. Non-symbolic magnitude comparison and estimation tasks were used to assess number sense. Between-group differences were found in symbolic and non-symbolic numerical tasks, but not in working memory tasks. Children in the met+ group showed better performance in all numerical tasks while val homozygous children presented slower development of non-symbolic magnitude representations. These results suggest COMT-related dopaminergic modulation may be related not only to working memory, as found in previous studies, but also to the development of magnitude processing and magnitude representations.

Clinical utility of polymorphisms in one-carbon metabolism for breast cancer risk prediction

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Shaik Mohammad Naushad

2011-01-01

Full Text Available This study addresses the issues in translating the laboratory derived data obtained during discovery phase of research to a clinical setting using a breast cancer model. Laboratory-based risk assessment indi-cated that a family history of breast cancer, reduced folate carrier 1 (RFC1 G80A, thymidylate synthase (TYMS 5’-UTR 28bp tandem repeat, methylene tetrahydrofolate reductase (MTHFR C677T and catecholamine-O-methyl transferase (COMT genetic polymorphisms in one-carbon metabolic pathway increase the risk for breast cancer. Glutamate carboxypeptidase II (GCPII C1561T and cytosolic serine hydroxymethyl transferase (cSHMT C1420T polymorphisms were found to decrease breast cancer risk. In order to test the clinical validity of this information in the risk prediction of breast cancer, data was stratified based on number of protective alleles into four categories and in each category sensitivity and 1-specificity values were obtained based on the distribution of number of risk alleles in cases and controls. Receiver operating characteristic (ROC curves were plotted and the area under ROC curve (C was used as a measure of discriminatory ability between cases and controls. In subjects without any protective allele, aberrations in one-carbon metabolism showed perfect prediction (C=0.93 while the predictability was lost in subjects with one protective allele (C=0.60. However, predictability increased steadily with increasing number of protective alleles (C=0.63 for 2 protective alleles and C=0.71 for 3 protective alleles. The cut-off point for discrimination was >4 alleles in all predictable combinations. Models of this kind can serve as valuable tools in translational re-search, especially in identifying high-risk individuals and reducing the disease risk either by life style modification or by medical intervention.

Gene polymorphisms of glutathione S-transferase omega 1 and 2, urinary arsenic methylation profile and urothelial carcinoma

Energy Technology Data Exchange (ETDEWEB)

Chung, Chi-Jung [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Pu, Yeong-Shiau [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Su, Chien-Tien [Department of Family Medicine, Taipei Medical University Hospital, Taipei, Taiwan (China); Huang, Chao-Yuan [Department of Urology, National Taiwan University Hospital, Taipei, Taiwan (China); Graduate Institute of Clinical Medicine, College of Medicine, Taipei Medical University (China); Hsueh, Yu-Mei, E-mail: ymhsueh@tmu.edu.tw [School of Public Health, College of Public Health and Nutrition, Taipei Medical University, Taipei, Taiwan (China); Department of Public Health, School of Medicine, College of Medicine, Taipei Medical University, Taipei, Taiwan (China)

2011-01-01

Genetic polymorphisms in arsenic-metabolizing enzymes may be involved in the biotransformation of inorganic arsenic and may increase the risk of developing urothelial carcinoma (UC). The present study evaluated the roles of glutathione S-transferase omega 1 (GSTO1) and GSTO2 polymorphisms in UC carcinogenesis. A hospital-based case-control study was conducted. Questionnaire information and biological specimens were collected from 149 UC cases and 251 healthy controls in a non-obvious inorganic arsenic exposure area in Taipei, Taiwan. The urinary arsenic profile was determined using high-performance liquid chromatography and hydride generator-atomic absorption spectrometry. Genotyping for GSTO1 Ala140Asp and GSTO2 Asn142Asp was conducted using polymerase chain reaction-restriction fragment length polymerase. GSTO1 Glu208Lys genotyping was performed using high-throughput matrix-assisted laser desorption and ionization time-of-flight mass spectrometry. A significant positive association was found between total arsenic, inorganic arsenic percentage and monomethylarsonic acid percentage and UC, while dimethylarsinic acid percentage was significantly inversely associated with UC. The minor allele frequency of GSTO1 Ala140Asp, GSTO1 Glu208Lys and GSTO2 Asn142Asp was 18%, 1% and 26%, respectively. A significantly higher MMA% was found in people who carried the wild type of GSTO1 140 Ala/Ala compared to those who carried the GSTO1 140 Ala/Asp and Asp/Asp genotype (p = 0.02). The homogenous variant genotype of GSTO2 142 Asp/Asp was inversely associated with UC risk (OR = 0.17; 95% CI, 0.03 - 0.88; p = 0.03). Large-scale studies will be required to verify the association between the single nucleotide polymorphisms of arsenic-metabolism-related enzymes and UC risk. - Research Highlights: {yields} The homogenous variant genotype of GSTO2 was inversely associated with UC risk. {yields} A higher urinary MMA% was found in people carrying the wild type of GSTO1 Ala140Asp. {yields

Neuron-astrocyte interaction enhance GABAergic synaptic transmission in a manner dependent on key metabolic enzymes.

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Przemysław eKaczor

2015-04-01

Full Text Available GABA is the major inhibitory neurotransmitter in the adult brain and mechanisms of GABAergic inhibition have been intensely investigated in the past decades. Recent studies provided evidence for an important role of astrocytes in shaping GABAergic currents. One of the most obvious, but yet poorly understood, mechanisms of the cross-talk between GABAergic currents and astrocytes is metabolism including neurotransmitter homeostasis. In particular, how modulation of GABAergic currents by astrocytes depends on key enzymes involved in cellular metabolism remains largely unknown. To address this issue, we have considered two simple models of neuronal cultures: nominally astrocyte-free neuronal culture (NC and neuronal-astrocytic co-cultures (ANCC and miniature Inhibitory Postsynaptic Currents (mIPSCs were recorded in control conditions and in the presence of respective enzyme blockers. We report that enrichment of neuronal culture with astrocytes results in a marked increase in mIPSC frequency. This enhancement of GABAergic activity was accompanied by increased number of GAD65 and vGAT puncta, indicating that at least a part of the frequency enhancement was due to increased number of synaptic contacts. Inhibition of glutamine synthetase (with MSO strongly reduced mIPSC frequency in ANCC but had no effect in NC. Moreover, treatment of ANCC with inhibitor of glycogen phosphorylase (BAYU6751 or with selective inhibitor of astrocytic Krebs cycle,fluoroacetate, resulted in a marked reduction of mIPSC frequency in ANCC having no effect in NC. We conclude that GABAergic synaptic transmission strongly depends on neuron-astrocyte interaction in a manner dependent on key metabolic enzymes as well as on the Krebs cycle.

Failure of Chemotherapy in Hepatocellular Carcinoma Due to Impaired and Dysregulated Primary Liver Drug Metabolizing Enzymes and Drug Transport Proteins: What to Do?

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Ul Islam, Salman; Ahmed, Muhammad Bilal; Shehzad, Adeeb; Ul-Islam, Mazhar; Lee, Young Sup

2018-05-28

Most of the drugs are metabolized in the liver by the action of drug metabolizing enzymes. In hepatocellular carcinoma (HCC), primary drug metabolizing enzymes are severely dysregulated, leading to failure of chemotherapy. Sorafenib is the only standard systemic drug available, but it still presents certain limitations, and much effort is required to understand who is responsive and who is refractory to the drug. Preventive and therapeutic approaches other than systemic chemotherapy include vaccination, chemoprevention, liver transplantation, surgical resection, and locoregional therapies. This review details the dysregulation of primary drug metabolizing enzymes and drug transport proteins of the liver in HCC and their influence on chemotherapeutic drugs. Furthermore, it emphasizes the adoption of safe alternative therapeutic strategies to chemotherapy. The future of HCC treatment should emphasize the understanding of resistance mechanisms and the finding of novel, safe, and efficacious therapeutic strategies, which will surely benefit patients affected by advanced HCC. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

[Effect of Low-Intensity 900 MHz Frequency Electromagnetic Radiation on Rat Brain Enzyme Activities Linked to Energy Metabolism].

Science.gov (United States)

Petrosyan, M S; Nersesova, L S; Gazaryants, M G; Meliksetyan, G O; Malakyan, M G; Bajinyan, S A; Akopian, J I

2015-01-01

The research deals with the effect of low-intensity 900 MHz frequency electromagnetic radiation (EMR), power density 25 μW/cm2, on the following rat brain and blood serum enzyme activities: creatine kinase (CK), playing a central role in the process of storing and distributing the cell energy, as well as alanine aminotransferase (ALT) and aspartate aminotransferase (AST) that play a key role in providing the conjunction of carbohydrate and amino acid metabolism. The comparative analysis of the changes in the enzyme activity studied at different times following the two-hour single, as well as fractional, radiation equivalent of the total time showed that the most radiosensitive enzyme is the brain creatine kinase, which may then be recommended as a marker of the radio frequency radiation impact. According to the analysis of the changing dynamics of the CK, ALT and AST activity level, with time these changes acquire the adaptive character and are directed to compensate the damaged cell energy metabolism.

The Use of Angiotensin-I Converting Enzyme I/D Genetic Polymorphism as a Biomarker of Athletic Performance in Humans

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Maria Fernanda De Mello Costa

2012-10-01

Full Text Available Angiotensin II is a key regulator of blood pressure and cardiovascular function in mammals. The conversion of angiotensin into its active form is carried out by Angiotensin I-Converting Enzyme (ACE. The measurement of ACE concentration in plasma or serum, its enzymatic activity, and the correlation between an insertion/deletion (I/D genetic polymorphism of the ACE gene have been investigated as possible indicators of superior athletic performance in humans. In this context, other indicators of superior adaptation to exercise resulting in better athletic performance (such as ventricular hypertrophy, VO2 max, and competition results were mostly used to study the association between ACE I/D polymorphism and improved performance. Despite the fact that the existing literature presents little consensus, there is sufficient scientific evidence to warrant further investigation on the usage of ACE activity and the I/D ACE gene polymorphism as biomarkers of superior athletic performance in humans of specific ethnicities or in athletes involved in certain sports. In this sense, a biomarker would be a substance or genetic component that could be measured to provide a degree of certainty, or an indication, of the presence of a certain trait or characteristic that would be beneficial to the athlete’s performance. Difficulties in interpreting and comparing the results of scientific research on the topic arise from dissimilar protocols and variation in study design. This review aims to investigate the current literature on the use of ACE I/D polymorphism as a biomarker of performance in humans through the comparison of scientific publications.

The Metabolic Response of Skeletal Muscle to Endurance Exercise Is Modified by the ACE-I/D Gene Polymorphism and Training State

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Paola Valdivieso

2017-12-01

Full Text Available The insertion/deletion polymorphism in the gene for the regulator of vascular tone, angiotensin-converting enzyme (ACE, is the prototype of a genetic influence on physical fitness and this involves an influence on capillary supply lines and dependent aerobic metabolism in skeletal muscle. The respective interaction of ACE-I/D genotype and training status on local metabolic and angiogenic reactions in exercised muscle is not known. Toward this end we characterized the metabolomic and angiogenic response in knee extensor muscle, m. vastus lateralis, in 18 untrained and 34 endurance-trained (physically active, V˙O2max > 50 mL min−1 kg−1 white British men to an exhaustive bout of one-legged cycling exercise. We hypothesized that training status and ACE-I/D genotype affect supply-related muscle characteristics of exercise performance in correspondence to ACE expression and angiotensin 2 levels. ACE-I/D genotype and training status developed an interaction effect on the cross-sectional area (CSA of m. vastus lateralis and mean CSA of slow type fibers, which correlated with peak power output (r ≥ 0.44. Genotype × training interactions in muscle also resolved for exercise-induced alterations of 22 metabolites, 8 lipids, glycogen concentration (p = 0.016, ACE transcript levels (p = 0.037, and by trend for the pro-angiogenic factor tenascin-C post exercise (p = 0.064. Capillary density (p = 0.001, capillary-to-fiber ratio (p = 0.010, systolic blood pressure (p = 0.014, and exercise-induced alterations in the pro-angiogenic protein VEGF (p = 0.043 depended on the ACE-I/D genotype alone. Our observations indicate that variability in aerobic performance in the studied subjects was in part reflected by an ACE-I/D-genotype-modulated metabolic phenotype of a major locomotor muscle. Repeated endurance exercise appeared to override this genetic influence in skeletal muscle by altering the ACE-related metabolic response and molecular aspects of the

The Metabolic Response of Skeletal Muscle to Endurance Exercise Is Modified by the ACE-I/D Gene Polymorphism and Training State.

Science.gov (United States)

Valdivieso, Paola; Vaughan, David; Laczko, Endre; Brogioli, Michael; Waldron, Sarah; Rittweger, Jörn; Flück, Martin

2017-01-01

The insertion/deletion polymorphism in the gene for the regulator of vascular tone, angiotensin-converting enzyme (ACE), is the prototype of a genetic influence on physical fitness and this involves an influence on capillary supply lines and dependent aerobic metabolism in skeletal muscle. The respective interaction of ACE-I/D genotype and training status on local metabolic and angiogenic reactions in exercised muscle is not known. Toward this end we characterized the metabolomic and angiogenic response in knee extensor muscle, m. vastus lateralis , in 18 untrained and 34 endurance-trained (physically active, [Formula: see text]O2max > 50 mL min -1 kg -1 ) white British men to an exhaustive bout of one-legged cycling exercise. We hypothesized that training status and ACE-I/D genotype affect supply-related muscle characteristics of exercise performance in correspondence to ACE expression and angiotensin 2 levels. ACE-I/D genotype and training status developed an interaction effect on the cross-sectional area (CSA) of m. vastus lateralis and mean CSA of slow type fibers, which correlated with peak power output ( r ≥ 0.44). Genotype × training interactions in muscle also resolved for exercise-induced alterations of 22 metabolites, 8 lipids, glycogen concentration ( p = 0.016), ACE transcript levels ( p = 0.037), and by trend for the pro-angiogenic factor tenascin-C post exercise ( p = 0.064). Capillary density ( p = 0.001), capillary-to-fiber ratio ( p = 0.010), systolic blood pressure ( p = 0.014), and exercise-induced alterations in the pro-angiogenic protein VEGF ( p = 0.043) depended on the ACE-I/D genotype alone. Our observations indicate that variability in aerobic performance in the studied subjects was in part reflected by an ACE-I/D-genotype-modulated metabolic phenotype of a major locomotor muscle. Repeated endurance exercise appeared to override this genetic influence in skeletal muscle by altering the ACE-related metabolic response and molecular aspects

Interference of aldehyde metabolizing enzyme with diamine oxidase/histaminase/activity as determined by /sup 14/C putrescine method

Energy Technology Data Exchange (ETDEWEB)

Fogel, W A [Polish Academy of Sciences, Cracow (Poland). Inst. of Pharmacology; Bieganski, T; Wozniak, J; Maslinski, C

1978-01-01

The ..delta../sup 1/ pyrroline formation, as an indicator of diamine oxidase activity according to Okuyama and Kobayashi /sup 14/C putrescine test (1961, Archs Biochem. Biophys., vol.95, 242), has been investigated in several tissue homogenates. When guinea pig liver homogenate was used as a source of enzyme in the presence of aldehyde dehydrogenase inhibitors chlorate hydrate and acetaldehyde the level of formation ..delta../sup 1/ pyrroline was strongly increased in a dose-dependent manner. Also inhibition of aldehyde reductase by phenobarbital enhanced ..delta../sup 1/ pyrroline formation, but to a lesser degree. In other tissues, with very high initial diamine oxidase activity (rat intestine, dog kidney) or with very low diamine oxidase activity (guinea pig skin, dog liver) the influence of these inhibitors was only slight. Pyrazole, an inhibitor of alcohol dehydrogenase exerted only a small effect on ..delta../sup 1/ pyrroline formation. All aldehyde-metabolizing enzymes inhibitors, except pyrazole, were without effect on purified pea seddling and hog kidney diamine oxidases. The use of aldehyde-metabolizing enzymes inhibitors may help to reveal the real values of diamine oxidase activity, when tissues homogenates are used as a source of enzyme.

Association of genetic polymorphisms of PON1 and CETP with the presence of metabolic syndrome; the effects of genotypes on their serum activity and concentrations

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Behdokht Fathi Dizaji

2018-01-01

Conclusions: There were no associations between the PON1 polymorphisms, or haplotypes with MetS. There was an association between CETPrs5882 and metabolic syndrome. AA genotype of CETPrs5882 appeared to be protective against MetS in our studied population. There were no association between the PON1 and CETP polymorphisms with PON1enzymatic activities and CETP protein levels at base line and after curcumin supplementation.

Angiotensin Converting Enzyme Gene I/D Polymorphism in Pakistani Rheumatic Heart Disease Patients and Healthy Controls

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Sadia Rehman

2015-09-01

Full Text Available Background: Valve scarring and collagen deposition are crucial in pathogenesis of Rheumatic Heart Disease (RHD, an autoimmune disorder of the heart. Angiotensin I-Converting Enzyme (ACE plays a major role in fibrous tissue formation. Objectives: The present research work aimed to assess the role of ACE Insertion/Deletion (I/D polymorphism in progress of RHD. Patients and Methods: DNA was pre pared from blood samples from 156 RHD patients (156 and 204 healthy ethnically-matched controls. Then, it was screened using sequence-specific Primers. Polymerase chain reaction and Agarose gel electrophoresis. The data were analyzed using Vassar stats (http://faculty.vassar.edu/lowry/VassarStats.html. Results: I allele (P = 0.024, OR = 1.42 and II genotype (P = 0.001, OR = 3.07 were significantly higher in Pakistani RHD patients compared to the healthy controls. Also, a significant difference was found between the female, but not male, patients and the controls regarding I allele and II genotype. Conclusions: The study results provided information about involvement of ACE I/D polymorphism in molecular mechanism of RHD. Thus, it can become one of the useful tools in risk assessment and help with designing strategies to combat the disease.

Abnormal islet sphingolipid metabolism in type 1 diabetes.

Science.gov (United States)

Holm, Laurits J; Krogvold, Lars; Hasselby, Jane P; Kaur, Simranjeet; Claessens, Laura A; Russell, Mark A; Mathews, Clayton E; Hanssen, Kristian F; Morgan, Noel G; Koeleman, Bobby P C; Roep, Bart O; Gerling, Ivan C; Pociot, Flemming; Dahl-Jørgensen, Knut; Buschard, Karsten

2018-04-18

Sphingolipids play important roles in beta cell physiology, by regulating proinsulin folding and insulin secretion and in controlling apoptosis, as studied in animal models and cell cultures. Here we investigate whether sphingolipid metabolism may contribute to the pathogenesis of human type 1 diabetes and whether increasing the levels of the sphingolipid sulfatide would prevent models of diabetes in NOD mice. We examined the amount and distribution of sulfatide in human pancreatic islets by immunohistochemistry, immunofluorescence and electron microscopy. Transcriptional analysis was used to evaluate expression of sphingolipid-related genes in isolated human islets. Genome-wide association studies (GWAS) and a T cell proliferation assay were used to identify type 1 diabetes related polymorphisms and test how these affect cellular islet autoimmunity. Finally, we treated NOD mice with fenofibrate, a known activator of sulfatide biosynthesis, to evaluate the effect on experimental autoimmune diabetes development. We found reduced amounts of sulfatide, 23% of the levels in control participants, in pancreatic islets of individuals with newly diagnosed type 1 diabetes, which were associated with reduced expression of enzymes involved in sphingolipid metabolism. Next, we discovered eight gene polymorphisms (ORMDL3, SPHK2, B4GALNT1, SLC1A5, GALC, PPARD, PPARG and B4GALT1) involved in sphingolipid metabolism that contribute to the genetic predisposition to type 1 diabetes. These gene polymorphisms correlated with the degree of cellular islet autoimmunity in a cohort of individuals with type 1 diabetes. Finally, using fenofibrate, which activates sulfatide biosynthesis, we completely prevented diabetes in NOD mice and even reversed the disease in half of otherwise diabetic animals. These results indicate that islet sphingolipid metabolism is abnormal in type 1 diabetes and suggest that modulation may represent a novel therapeutic approach. The RNA expression data is

Genes encoding enzymes of the lignin biosynthesis pathway in Eucalyptus

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Ricardo Harakava

2005-01-01

Full Text Available Eucalyptus ESTs libraries were screened for genes involved in lignin biosynthesis. This search was performed under the perspective of recent revisions on the monolignols biosynthetic pathway. Eucalyptus orthologues of all genes of the phenylpropanoid pathway leading to lignin biosynthesis reported in other plant species were identified. A library made with mRNAs extracted from wood was enriched for genes involved in lignin biosynthesis and allowed to infer the isoforms of each gene family that play a major role in wood lignin formation. Analysis of the wood library suggests that, besides the enzymes of the phenylpropanoids pathway, chitinases, laccases, and dirigent proteins are also important for lignification. Colocalization of several enzymes on the endoplasmic reticulum membrane, as predicted by amino acid sequence analysis, supports the existence of metabolic channeling in the phenylpropanoid pathway. This study establishes a framework for future investigations on gene expression level, protein expression and enzymatic assays, sequence polymorphisms, and genetic engineering.

Characterization of the hepatic cytochrome P450 enzymes involved in the metabolism of 25I-NBOMe and 25I-NBOH

DEFF Research Database (Denmark)

Nielsen, Line Marie; Holm, Niels Bjerre; Leth-Petersen, Sebastian

2017-01-01

)ethylamino]methyl]phenol (25I-NBOH) and to characterize the metabolites. The following approaches were used to identify the main enzymes involved in primary metabolism: incubation with a panel of CYP and monoamine oxidase (MAO) enzymes and incubation in pooled human liver microsomes (HLM) with and without specific CYP...

Effects of pesticide chemicals on the activity of metabolic enzymes: focus on thiocarbamates.

Science.gov (United States)

Mathieu, Cécile; Duval, Romain; Xu, Ximing; Rodrigues-Lima, Fernando; Dupret, Jean-Marie

2015-01-01

Thiocarbamates are chemicals widely used as pesticides. Occupational exposure is associated with acute intoxication. Populations can be exposed through food and water. Moreover, certain thiocarbamates are used clinically. The widespread use of thiocarbamates raises many issues regarding their toxicological and pharmacological impact. Thiocarbamates and their metabolites can modify biological macromolecules functions, in particular enzymes, through modification of cysteine residues, chelation of metal ions or modulation of the oxidative stress. Loss of enzyme activity can lead to the disruption of metabolic pathways, and explain, at least in part, the effects of these pesticides. Additionally, their reactivity and ability to easily cross biological barrier confer them a great interest for development of clinical applications. Many advances in the study of thiocarbamates metabolism and reactivity have led to a better knowledge of biological effects of these compounds. However, more data are needed on the determination of targets and specificity. Only few data concerning the exposure to a cocktail of pesticides/chemicals are available, raising the need to evaluate the toxic side effects of representative pesticides mixtures. Moreover, the dithiocarbamate Disulfiram has shown great potential in therapeutic applications and leads to the development of pharmacological thiocarbamates derivatives, highly specific to their target and easily distributed.

Correlation of methylenetetrahydrofolate reductase polymorphism with Hcy metabolism and inflammatory response in patients with recurrent cerebral infarction

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Gai-Zhuang Liu

2017-07-01

Full Text Available Objective: To study the correlation of methylenetetrahydrofolate reductase (MTHFR polymorphism with Hcy metabolism and inflammatory response in patients with recurrent cerebral infarction. Methods: 40 patients with recurrent cerebral infarction who were treated in Yulin Third Hospital between December 2013 and December 2016 were selected as recurrent group, 58 patients with primary cerebral infarction were selected as primary group, and 60 healthy volunteers were selected as control group. Peripheral blood MTHFR gene C677T polymorphism and serum levels of Hcy metabolism indexes and inflammatory response indicators were determined. Results: CC genotype constituent ratio of recurrent group was significantly lower than that of primary group and control group while CT genotype and TT genotype constituent ratio were significantly higher than those of primary group and control group; serum Hcy, HMGB1, sCD40L, YKL-40, Lp-PLA2 and MMP-9 levels in recurrent group and primary group were significantly higher than those in control group while VitB12 and FA levels were significantly lower than those in control group; serum Hcy, HMGB1, sCD40L, YKL-40, Lp-PLA2 and MMP-9 levels in recurrent group were significantly higher than those in primary group while VitB12 and FA levels were significantly lower than those in primary group. Serum Hcy, HMGB1, sCD40L, YKL-40, Lp-PLA2 and MMP-9 levels in patients with CC genotype were significantly lower than those in patients with CT genotype and TT genotype while VitB12 and FA levels were significantly higher than those in patients with CT genotype and TT genotype; serum Hcy, HMGB1, sCD40L, YKL-40, Lp-PLA2 and MMP-9 levels in patients with CT genotype were significantly lower than those in patients with TT genotype while VitB12 and FA levels were significantly higher than those in patients with TT genotype. Conclusion: MTHFR gene C677T polymorphism is closely related to the recurrence of cerebral infarction, and allele C

Methylenetetrahydrofolate reductase gene polymorphism in type 1 ...

African Journals Online (AJOL)

In patients with type-I diabetes mellitus folate deficiency is associated with endothelial dysfunction. So, polymorphism in genes involved in folate metabolism may have a role in vascular disease. This study was designed to evaluate the relationship between methylenetetrahydrofolate reductase (MTHFR) gene polymorphism ...

Angiotensin-converting enzyme insertion/deletion polymorphism association with obesity and some related disorders in Egyptian females: a case-control observational study

OpenAIRE

Motawi, Tarek K.; Shaker, Olfat G.; Shahin, Nancy N.; Ahmed, Nancy M.

2016-01-01

Background According to the WHO report in 2015, obesity is the fifth leading cause of death worldwide, and the prevalence of Egyptian female obesity is 37.5?%. Since obesity is highly influenced by genetics, and adipose tissue renin-angiotensin system is over-activated in obesity, the effect of angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism on obesity and related disorders was studied in several populations, because of its effect on ACE activity. Our objective was t...

Activity of metabolic enzymes and muscle-specific gene expression in parr and smolts Atlantic salmon Salmo salar L. of different age groups.

Science.gov (United States)

Churova, Maria V; Meshcheryakova, Olga V; Veselov, Aleksey E; Efremov, Denis A; Nemova, Nina N

2017-08-01

This study was conducted to characterize the energy metabolism level and the features of muscle growth regulation during the development of Atlantic salmon (Salmo salar) inhabiting the Indera River (Kola Peninsula, Russia). The activities of aerobic and anaerobic enzymes (cytochrome c oxidase and lactate dehydrogenase) and carbohydrate metabolism enzymes (glucose-6-phosphate dehydrogenase, glycerol-3-phosphate dehydrogenase, and aldolase) were measured in muscle and liver tissue. Gene expression levels of myosin heavy chain (MyHC), myostatin (MSTN-1a), and myogenic regulatory factors (MRFs-MyoD1a, MyoD1b, MyoD1c, Myf5, myogenin) were measured in the white muscles of salmon parr of ages 0+, 1+, 2+, and 3+ and smolts of ages 2+ and 3+. Multidirectional changes in the activity of enzymes involved in aerobic and anaerobic energy metabolism with age were shown in the white muscles of the parr. The cytochrome c oxidase activity was higher in muscles of underyearlings (0+) and yearlings (1+) and decreased in 2+ and 3+ age groups. The activity of lactate dehydrogenase, in contrast, increased with age. The patterns of changes in expression levels of MyoD1a, MyoD1b, myogenin, MyHC, and MSTN-1a at different ages of the parr were similar. Particularly, the expression of these genes peaked in the yearling parr (1+) and then decreased in elder groups. The differences were revealed in parameters studied between the parr and smolts. The level of aerobic and anaerobic metabolism enzyme activities was higher in the white muscles of smolts than in parr. The activity of carbohydrate metabolism enzymes was decreased in the smolts' livers. The expression levels of MyHC, MyoD1a, MyoD1b, and myogenin were lower in smolts at age 2+ compared to parr. These findings expand our knowledge of age-related and stage-related features of energy metabolism and muscle development regulation in young Atlantic salmon in their natural habitat. The results might be used for monitoring of the salmon

Metabolic organization and effects of feeding on enzyme activities of the dogfish shark (Squalus acanthias) rectal gland.

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Walsh, Patrick J; Kajimura, Makiko; Mommsen, Thomas P; Wood, Chris M

2006-08-01

In order to investigate the metabolic poise of the elasmobranch rectal gland, we conducted two lines of experimentation. First, we examined the effects of feeding on plasma metabolites and enzyme activities from several metabolic pathways in several tissues of the dogfish shark, Squalus acanthias, after starvation and at 6, 20, 30 and 48 h post-feeding. We found a rapid and sustained ten-fold decrease in plasma beta-hydroxybutyrate at 6 h and beyond compared with starved dogfish, suggesting an upregulation in the use of this substrate, a decrease in production, or both. Plasma acetoacetate levels remain unchanged, whereas there was a slight and transient decrease in plasma glucose levels at 6 h. Several enzymes showed a large increase in activity post-feeding, including beta-hydroxybutyrate dehydrogenase in rectal gland and liver, and in rectal gland, isocitrate dehydrogenase, citrate synthase, lactate dehydrogenase, aspartate amino transferase, alanine amino transferase, glutamine synthetase and Na(+)/K(+) ATPase. Also notable in these enzyme measurements was the overall high level of activity in the rectal gland in general. For example, activity of the Krebs' TCA cycle enzyme citrate synthase (over 30 U g(-1)) was similar to activities in muscle from other species of highly active fish. Surprisingly, lactate dehydrogenase activity in the gland was also high (over 150 U g(-1)), suggesting either an ability to produce lactate anaerobically or use lactate as an aerobic fuel. Given these interesting observations, in the second aspect of the study we examined the ability of several metabolic substrates (alone and in combination) to support chloride secretion by the rectal gland. Among the substrates tested at physiological concentrations (glucose, beta-hydroxybutyrate, lactate, alanine, acetoacetate, and glutamate), only glucose could consistently maintain a viable preparation. Whereas beta-hydroxybutyrate could enhance gland activity when presented in combination

Is the alkaline tide a signal to activate metabolic or ionoregulatory enzymes in the dogfish shark (Squalus acanthias)?

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Wood, Chris M; Kajimura, Makiko; Mommsen, Thomas P; Walsh, Patrick J

2008-01-01

Experimental metabolic alkalosis is known to stimulate whole-animal urea production and active ion secretion by the rectal gland in the dogfish shark. Furthermore, recent evidence indicates that a marked alkaline tide (systemic metabolic alkalosis) follows feeding in this species and that the activities of the enzymes of the ornithine-urea cycle (OUC) for urea synthesis in skeletal muscle and liver and of energy metabolism and ion transport in the rectal gland are increased at this time. We therefore evaluated whether alkalosis and/or NaCl/volume loading (which also occurs with feeding) could serve as a signal for activation of these enzymes independent of nutrient loading. Fasted dogfish were infused for 20 h with either 500 mmol L(-1) NaHCO3 (alkalosis + volume expansion) or 500 mmol L(-1) NaCl (volume expansion alone), both isosmotic to dogfish plasma, at a rate of 3 mL kg(-1) h(-1). NaHCO3 infusion progressively raised arterial pH to 8.28 (control = 7.85) and plasma [HCO3-] to 20.8 mmol L(-1) (control = 4.5 mmol L(-1)) at 20 h, with unchanged arterial P(CO2), whereas NaCl/volume loading had no effect on blood acid-base status. Rectal gland Na+,K+-ATPase activity was increased 50% by NaCl loading and more than 100% by NaHCO3 loading, indicating stimulatory effects of both volume expansion and alkalosis. Rectal gland lactate dehydrogenase activity was elevated 25% by both treatments, indicating volume expansion effects only, whereas neither treatment increased the activities of the aerobic enzymes citrate synthase, NADP-isocitrate dehydrogenase, or the ketone body-utilizing enzyme beta-hydroxybutyrate dehydrogenase in the rectal gland or liver. The activity of ornithine-citrulline transcarbamoylase in skeletal muscle was doubled by NaHCO3 infusion, but neither treatment altered the activities of other OUC-related enzymes (glutamine synthetase, carbamoylphosphate synthetase III). We conclude that both the alkaline tide and salt loading/volume expansion act as

Simple and robust determination of the activity signature of key carbohydrate metabolism enzymes for physiological phenotyping in model and crop plants

DEFF Research Database (Denmark)

Jammer, Alexandra; Gasperl, Anna; Luschin-Ebengreuth, Nora

2015-01-01

The analysis of physiological parameters is important to understand the link between plant phenotypes and their genetic bases, and therefore is needed as an important element in the analysis of model and crop plants. The activities of enzymes involved in primary carbohydrate metabolism have been...... shown to be strongly associated with growth performance, crop yield, and quality, as well as stress responses. A simple, fast, and cost-effective method to determine activities for 13 key enzymes involved in carbohydrate metabolism has been established, mainly based on coupled spectrophotometric kinetic...

The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

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Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

1981-01-01

The effects of space flight conditions on the activities of certain enzymes regulating carbohydrate and lipid metabolism in rat liver are investigated in an attempt to account for the losses in body weight observed during space flight despite preflight caloric consumption. Liver samples were analyzed for the activities of 32 cytosolic and microsomal enzymes as well as hepatic glycogen and individual fatty acid levels for ground control rats and rats flown on board the Cosmos 936 biosatellite under normal space flight conditions and in centrifuges which were sacrificed upon recovery or 25 days after recovery. Significant decreases in the activities of glycogen phosphorylase, alpha-glycerol phosphate acyl transferase, diglyceride acyl transferase, aconitase and 6-phosphogluconate dehydrogenase and an increase in palmitoyl CoA desaturase are found in the flight stationary relative to the flight contrifuged rats upon recovery, with all enzymes showing alterations returning to normal values 25 days postflight. The flight stationary group is also observed to be characterized by more than twice the amount of liver glycogen of the flight centrifuged group as well as a significant increase in the ratio of palmitic to palmitoleic acid. Results thus indicate metabolic changes which may be involved in the mechanism of weight loss during weightlessness, and demonstrate the equivalence of centrifugation during space flight to terrestrial gravity.

Renin angiotensin system blockage associates with insertion/deletion polymorphism of angiotensin-converting enzyme in patients with hypertensive emergency.

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Vilela-Martin, José F; Vaz-de-Melo, Renan O; Cosenso-Martin, Luciana N; Kuniyoshi, Cristina H; Yugar-Toledo, Juan C; Pinhel, Marcela A S; de Souza, Gisele F; Souza, Dorotéia R S; Pimenta, Eduardo; Moreno, Heitor; Cipullo, José P

2013-09-01

Hypertensive crisis (HC) stands out as a form of acute elevation of blood pressure (BP). It can manifest itself as hypertensive emergency (HE) or hypertensive urgency (HU), which is usually accompanied with levels of diastolic BP ≥120 mmHg. Angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism may influence manifestations of HC. Thus, this study evaluated the influence of ACE I/D polymorphism in individuals with HC. A total of 187 patients admitted with HC (HU [n=69] and HE [n=118]) and 75 normotensive individuals were included in the study. Peripheral blood was drawn for a biochemical and genetic analysis of the ACE I/D polymorphism by Polymerase Chain Reaction. HC group showed higher systolic BP, body mass index (BMI), glycemia, creatinine, and lower high-density lipoprotein (HDL) cholesterol compared with normotensive individuals. The use of renin-angiotensin system (RAS) blockers was more frequent in the HU group than in the HE group (p=0.020). The II genotype was more predominant in normotensive and HU individuals than among HE individuals (18.7%, 11.6%, and 2.5%, respectively; p=0.004). Higher BMI and glycemia were associated with HC in the logistic regression model. ACE II genotype (odds ratio [OR] 0.14; 95% confidence interval [CI] 0.04-0.51) and HDL cholesterol were protective for the development of HE. ACE II genotype was present in the HU group, compared with the HE group (OR 0.18; 95% CI 0.04-0.88). This study shows an association between the low prevalence of ACE I/D polymorphism II genotype and a greater occurrence of HE in Brazilian individuals. The lower blockage of RAS, which was detected in the HE group, may interact with the low frequency of II genotype, conferring an increased risk for HE.

Effects of atorvastatin and T-786C polymorphism of eNOS gene on plasma metabolic lipid parameters.

Science.gov (United States)

Zago, Vanessa Helena de Souza; Santos, José Eduardo Tanus dos; Danelon, Mirian Regina Gardin; Silva, Roger Marcelo Mesquita da; Panzoldo, Natália Baratella; Parra, Eliane Soler; Alexandre, Fernanda; Virgínio, Vítor Wilson de Moura; Quintão, Eder Carlos Rocha; Faria, Eliana Cotta de

2013-01-01

Endothelial nitric oxide synthase (eNOS) activity may be modulated by high-density lipoprotein cholesterol (HDL-C), statins or polymorphisms, such as the T-786C of eNOS. This study aimed at evaluating if the T-786C polymorphism is associated with changes of atorvastatin effects on the lipid profile, on the concentrations of metabolites of nitric oxide (NO) and of high sensitivity C-reactive protein (hsCRP). Thirty male volunteers, asymptomatic, aged between 18 and 56 years were genotyped and classified according to absence (TT, n = 15) or presence (CC, n = 15) of the polymorphism. They were randomly selected for the use of placebo or atorvastatin (10 mg/day/14 days). After each treatment lipids, lipoproteins, HDL2 and HDL3 composition, cholesteryl ester transfer protein (CETP) activity, metabolites of NO and hsCRP were evaluated. The comparisons between genotypes after placebo showed an increase in CETP activity in a polymorphism-dependent way (TT, 12±7; CC, 22±12; p < 0.05). The interaction analyses between treatments indicated that atorvastatin has an effect on cholesterol, LDL, nitrite and lipid-protein ratios (HDL2 and HDL3) (p < 0.001) in both genotypes. Interestingly, we observed genotype/drug interactions on CETP (p < 0.07) and lipoprotein (a) (Lp(a)) (p < 0.056), leading to a borderline decrease in CETP, but with no effect on Lp(a). HsCRP showed no alteration. These results suggest that statin treatment may be relevant for primary prevention of atherosclerosis in patients with the T-786C polymorphism of eNOS, considering the effects on lipid metabolism.

Distribution of Angiotensin-1 Converting Enzyme Insertion/Deletion and α-Actinin-3 Codon 577 Polymorphisms in Turkish Male Soccer Players

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Korkut Ulucan

2015-01-01

Full Text Available Angiotensin-1 converting enzyme (ACE gene and α-actinin-3 (ACTN3 gene polymorphisms are considered to be the most important candidate genes for genetic predisposition to human athletic performance. In the present study, we aimed to analyze the distribution of ACE and ACTN3 polymorphisms for the first time in male Turkish soccer players. In this prospective study, our cohort consisted of 25 professional players, all with Turkish ancestry. Polymerase chain reaction (PCR-restriction length polymorphism was used for the characterization of the genotype of ACTN3 and single PCR for ACE . For ACE genotype, 16%, 44%, and 40% of the players had insertion/insertion (II, insertion/deletion (ID, and deletion/deletion (DD genotypes, respectively, whereas 20% had XX, 36% had RX, and 44% had RR genotypes for ACTN3 . When we examined the allelic percentages, for ACE , D allele was recorded as 62 and I as 38, and for ACTN3 , R allele was 62 and X was 38. Our results were in agreement with the previous reports, indicating the presence of ACTN3 D and ACE X allele in soccer players. We suggest that ACE and ACTN3 genotypes are important biomarkers for genetic counseling for the individuals who are prone to be successful soccer players.

The V279F polymorphism might change protein character and ...

African Journals Online (AJOL)

Polymorphisms at the protein level are also estimated to correlate with increased risk factors for heart attacks. One such polymorphism is the V279F polymorphism in Lp-PLA2 which results in a change in enzyme performance capability. This in turn implies a reduced risk of acute myocardial infarct (AMI) in Korean and ...

In Vivo Exposure of Kaempferol Is Driven by Phase II Metabolic Enzymes and Efflux Transporters.

Science.gov (United States)

Zheng, Liang; Zhu, Lijun; Zhao, Min; Shi, Jian; Li, Yuhuan; Yu, Jia; Jiang, Huangyu; Wu, Jinjun; Tong, Yunli; Liu, Yuting; Hu, Ming; Lu, Linlin; Liu, Zhongqiu

2016-09-01

Kaempferol is a well-known flavonoid; however, it lacks extensive pharmacokinetic studies. Phase II metabolic enzymes and efflux transporters play an important role in the disposition of flavonoids. This study aimed to investigate the mechanism by which phase II metabolic enzymes and efflux transporters determine the in vivo exposure of kaempferol. Pharmacokinetic analysis in Sprague-Dawley rats revealed that kaempferol was mostly biotransformed to conjugates, namely, kaempferol-3-glucuronide (K-3-G), kaempferol-7-glucuronide (K-7-G), and kaempferol-7-sulfate, in plasma. K-3-G represented the major metabolite. Compared with that in wild-type mice, pharmacokinetics in knockout FVB mice demonstrated that the absence of multidrug resistance protein 2 (MRP2) and breast cancer resistance protein (BCRP) significantly increased the area under the curve (AUC) of the conjugates. The lack of MRP1 resulted in a much lower AUC of the conjugates. Intestinal perfusion in rats revealed that the glucuronide conjugates were mainly excreted in the small intestine, but 7-sulfate was mainly excreted in the colon. In Caco-2 monolayers, K-7-G efflux toward the apical (AP) side was significantly higher than K-3-G efflux. In contrast, K-3-G efflux toward the basolateral (BL) side was significantly higher than K-7-G efflux. The BL-to-AP efflux was significantly reduced in the presence of the MRP2 inhibitor LTC4. The AP-to-BL efflux was significantly decreased in the presence of the BL-side MRPs inhibitor MK571. The BCRP inhibitor Ko143 decreased the glucuronide conjugate efflux. Therefore, kaempferol is mainly exposed as K-3-G in vivo, which is driven by phase II metabolic enzymes and efflux transporters (i.e., BCRP and MRPs).

Association of Polymorphisms of Genes Involved in Lipid Metabolism with Blood Pressure and Lipid Values in Mexican Hypertensive Individuals

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Blanca Estela Ríos-González

2014-01-01

Full Text Available Hypertension and dyslipidemia exhibit an important clinical relationship because an increase in blood lipids yields an increase in blood pressure (BP. We analyzed the associations of seven polymorphisms of genes involved in lipid metabolism (APOA5 rs3135506, APOB rs1042031, FABP2 rs1799883, LDLR rs5925, LIPC rs1800588, LPL rs328, and MTTP rs1800591 with blood pressure and lipid values in Mexican hypertensive (HT patients. A total of 160 HT patients and 160 normotensive individuals were included. Genotyping was performed through PCR-RFLP, PCR-AIRS, and sequencing. The results showed significant associations in the HT group and HT subgroups classified as normolipemic and hyperlipemic. The alleles FABP2 p.55T, LIPC −514T, and MTTP −493T were associated with elevated systolic BP. Five alleles were associated with lipids. LPL p.474X and FABP2 p.55T were associated with decreased total cholesterol and LDL-C, respectively; APOA5 p.19W with increased HDL-C; APOA5 p.19W and FABP2 p.55T with increased triglycerides; and APOB p.4181K and LDLR c.1959T with decreased triglycerides. The APOB p.E4181K polymorphism increases the risk for HT (OR = 1.85, 95% CI: 1.17–2.93; P=0.001 under the dominant model. These findings indicate that polymorphisms of lipid metabolism genes modify systolic BP and lipid levels and may be important in the development of essential hypertension and dyslipidemia in Mexican HT patients.

Early evolution of efficient enzymes and genome organization

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Szilágyi András

2012-10-01

Full Text Available Abstract Background Cellular life with complex metabolism probably evolved during the reign of RNA, when it served as both information carrier and enzyme. Jensen proposed that enzymes of primordial cells possessed broad specificities: they were generalist. When and under what conditions could primordial metabolism run by generalist enzymes evolve to contemporary-type metabolism run by specific enzymes? Results Here we show by numerical simulation of an enzyme-catalyzed reaction chain that specialist enzymes spread after the invention of the chromosome because protocells harbouring unlinked genes maintain largely non-specific enzymes to reduce their assortment load. When genes are linked on chromosomes, high enzyme specificity evolves because it increases biomass production, also by reducing taxation by side reactions. Conclusion The constitution of the genetic system has a profound influence on the limits of metabolic efficiency. The major evolutionary transition to chromosomes is thus proven to be a prerequisite for a complex metabolism. Furthermore, the appearance of specific enzymes opens the door for the evolution of their regulation. Reviewers This article was reviewed by Sándor Pongor, Gáspár Jékely, and Rob Knight.

Understanding specificity in metabolic pathways-Structural biology of human nucleotide metabolism

International Nuclear Information System (INIS)

Welin, Martin; Nordlund, Paer

2010-01-01

Interactions are the foundation of life at the molecular level. In the plethora of activities in the cell, the evolution of enzyme specificity requires the balancing of appropriate substrate affinity with a negative selection, in order to minimize interactions with other potential substrates in the cell. To understand the structural basis for enzyme specificity, the comparison of structural and biochemical data between enzymes within pathways using similar substrates and effectors is valuable. Nucleotide metabolism is one of the largest metabolic pathways in the human cell and is of outstanding therapeutic importance since it activates and catabolises nucleoside based anti-proliferative drugs and serves as a direct target for anti-proliferative drugs. In recent years the structural coverage of the enzymes involved in human nucleotide metabolism has been dramatically improved and is approaching completion. An important factor has been the contribution from the Structural Genomics Consortium (SGC) at Karolinska Institutet, which recently has solved 33 novel structures of enzymes and enzyme domains in human nucleotide metabolism pathways and homologs thereof. In this review we will discuss some of the principles for substrate specificity of enzymes in human nucleotide metabolism illustrated by a selected set of enzyme families where a detailed understanding of the structural determinants for specificity is now emerging.

Mitochondrial gene polymorphisms alter hepatic cellular energy metabolism and aggravate diet-induced non-alcoholic steatohepatitis

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Torsten Schröder

2016-04-01

Full Text Available Objective: Non-alcoholic fatty liver disease (NAFLD is the most common chronic liver disease and is associated with an enhanced risk for liver and cardiovascular diseases and mortality. NAFLD can progress from simple hepatic steatosis to non-alcoholic steatohepatitis (NASH. However, the mechanisms predisposing to this progression remain undefined. Notably, hepatic mitochondrial dysfunction is a common finding in patients with NASH. Due to a lack of appropriate experimental animal models, it has not been evaluated whether this mitochondrial dysfunction plays a causative role for the development of NASH. Methods: To determine the effect of a well-defined mitochondrial dysfunction on liver physiology at baseline and during dietary challenge, C57BL/6J-mtFVB/N mice were employed. This conplastic inbred strain has been previously reported to exhibit decreased mitochondrial respiration likely linked to a non-synonymous gene variation (nt7778 G/T of the mitochondrial ATP synthase protein 8 (mt-ATP8. Results: At baseline conditions, C57BL/6J-mtFVB/N mice displayed hepatic mitochondrial dysfunction characterized by decreased ATP production and increased formation of reactive oxygen species (ROS. Moreover, genes affecting lipid metabolism were differentially expressed, hepatic triglyceride and cholesterol levels were changed in these animals, and various acyl-carnitines were altered, pointing towards an impaired mitochondrial carnitine shuttle. However, over a period of twelve months, no spontaneous hepatic steatosis or inflammation was observed. On the other hand, upon dietary challenge with either a methionine and choline deficient diet or a western-style diet, C57BL/6J-mtFVB/N mice developed aggravated steatohepatitis as characterized by lipid accumulation, ballooning of hepatocytes and infiltration of immune cells. Conclusions: We observed distinct metabolic alterations in mice with a mitochondrial polymorphism associated hepatic mitochondrial

Single-nucleotide polymorphisms in peroxisome proliferator ...

Indian Academy of Sciences (India)

However, association of these polymorphisms with the metabolic syndrome and its individual components has not been well investigated in the Indian population. The Indian population harbours the maximum number of diabetics in the world who are thus more susceptible to metabolic disorders. We screened a South ...

The NAD+ metabolism of Leishmania, notably the enzyme nicotinamidase involved in NAD+ salvage, offers prospects for development of anti-parasite chemotherapy.

Science.gov (United States)

Michels, Paul A M; Avilán, Luisana

2011-10-01

NAD+ plays multiple, essential roles in the cell. As a cofactor in many redox reactions it is key in the cellular energy metabolism and as a substrate it participates in many reactions leading to a variety of covalent modifications of enzymes with major roles in regulation of expression and metabolism. Cells may have the ability to produce this metabolite either via alternative de novo synthesis pathways and/or by different salvage pathways. In this issue of Molecular Microbiology, Gazanion et al. (2011) demonstrate that Leishmania species can only rely on the salvage of NAD+ building blocks. One of the enzymes involved, nicotinamidase, is absent from human cells. The enzyme is important for growth of Leishmania infantum and essential for establishing an infection. The crystal structure of the parasite protein has been solved and shows prospects for design of inhibitors to be used as leads for development of new drugs. Indeed, NAD+ metabolism is currently being considered as a promising drug target in various diseases and the vulnerability of Leishmania for interference of this metabolism has been proved in previous work by the same group, by showing that administration of NAD+ precursors has detrimental effect on the pathogenic, amastigote stage of this parasite. © 2011 Blackwell Publishing Ltd.

The effects of space flight on some rat liver enzymes regulating carbohydrate and lipid metabolism

Science.gov (United States)

Abraham, S.; Lin, C. Y.; Klein, H. P.; Volkmann, C.

We have examined, in the livers of rats carried aboard the Cosmos 936 biosatellite, the activities of about 30 enzymes concerned with carbohydrate and lipid metabolism. In addition to the enzyme studies, the levels of glycogen and of the individual fatty acids in hepatic lipids were determined. Livers from flight and ground control rats at recovery (R0) and 25 days after recovery (R25) were used for these analyses. For all parameters measured, the most meaningful comparisons are those made between flight stationary (FS) and flight centrifuged (FC) animals at R0. When these two groups of flight rats were compared at R0, statistically significant decreases in the activity levels of glycogen phosphorylase, α-glycerol phosphate acyl transferase, diglyceride acyl transferase, aconitase and 6-phosphogluconate dehydrogenase and an increase in the palmitoyl CoA desaturase were noted in the weightless group (FS). The significance of these findings was strengthened by the fact that all enzyme activities showing alterations at R0 returned to normal 25 days postflight. When liver glycogen and total fatty acids of the two sets of flight animals were determined, significant differences that could be attributed to reduced gravity were observed. The weightless group (FS) at R0 contained, on the average, more than twice the amount of glycogen than did the centrifuged controls (FC) and a remarkable shift in the ratio of palmitate to palmitoleate was noted. These metabolic alterations, both in enzyme levels and in hepatic constituents, appear to be characteristic of the weightless condition. Our data seem to justify the conclusion that centrifugation during flight is equivalent to terrestrial gravity.

[Features of allele polymorphism of genes involved in homocysteine and folate metabolism in patients with atherosclerosis of the lower extremity arteries].

Science.gov (United States)

Klenkova, N A; Kapustin, S I; Saltykova, N B; Shmeleva, V M; Blinov, M N

2009-01-01

Under study were features of allele polymorphism of genes of methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A 2756G), methionine synthase reductase (MTRR A66G) and methylenetetrahydrofolate dehydrogenase (MTHFD G1958A) in patients with atherosclerosis of the lower extremity arteries (ALEA). Patients with hyperhomocysteinemia (HHcy) had statistically significant increase of allele MTHFR 677T and MTRR 66GG as compared both with the control group and with the group of patients without HHcy. It suggests that polymorphism of genes involved in homocystein and folate metabolism might affect the risk of HHcy in patients with ALEA.

Short-term hepatic effects of depleted uranium on xenobiotic and bile acid metabolizing cytochrome P450 enzymes in the rat

International Nuclear Information System (INIS)

Gueguen, Y.; Souidi, M.; Baudelin, C.; Dudoignon, N.; Grison, S.; Dublineau, I.; Marquette, C.; Voisin, P.; Gourmelon, P.; Aigueperse, J.

2006-01-01

The toxicity of uranium has been demonstrated in different organs, including the kidneys, skeleton, central nervous system, and liver. However, few works have investigated the biological effects of uranium contamination on important metabolic function in the liver. In vivo studies were conducted to evaluate its effects on cytochrome P450 (CYP) enzymes involved in the metabolism of cholesterol and xenobiotics in the rat liver. The effects of depleted uranium (DU) contamination on Sprague-Dawley were measured at 1 and 3 days after exposure. Biochemical indicators characterizing liver and kidney functions were measured in the plasma. The DU affected bile acid CYP activity: 7α-hydroxycholesterol plasma level decreased by 52% at day 3 whereas microsomal CYP7A1 activity in the liver did not change significantly and mitochondrial CYP27A1 activity quintupled at day 1. Gene expression of the nuclear receptors related to lipid metabolism (FXR and LXR) also changed, while PPARα mRNA levels did not. The increased mRNA levels of the xenobiotic-metabolizing CYP3A enzyme at day 3 may be caused by feedback up-regulation due to the decreased CYP3A activity at day 1. CAR mRNA levels, which tripled on day 1, may be involved in this up-regulation, while mRNA levels of PXR did not change. These results indicate that high levels of depleted uranium, acting through modulation of the CYP enzymes and some of their nuclear receptors, affect the hepatic metabolism of bile acids and xenobiotics. (orig.)

AHSG tag single nucleotide polymorphisms associate with type 2 diabetes and dyslipidemia: studies of metabolic traits in 7,683 white Danish subjects

DEFF Research Database (Denmark)

Andersen, Gitte; Burgdorf, Kristoffer Sølvsten; Sparsø, Thomas

2008-01-01

been largely successful. We related seven frequent AHSG tag single nucleotide polymorphisms to a range of metabolic traits, including type 2 diabetes, obesity, and dyslipidemia. RESEARCH DESIGN AND METHODS: The polymorphisms were genotyped in 7,683 white Danish subjects using Taqman allelic...... with dyslipidemia (P = 0.003 and P(corr) = 0.009). Thr248Met (rs4917) tended to associate with lower fasting and post-oral glucose tolerance test serum insulin release (P = 0.02, P(corr) = 0.1 for fasting and P = 0.04, P(corr) = 0.2 for area under the insulin curve) and improved insulin sensitivity estimated...

Influence of Angiotensin-Converting-Enzyme Gene Polymorphism on Echocardiographic Data of Patients with Ischemic Heart Failure

Science.gov (United States)

Duque, Gustavo Salgado; da Silva, Dayse Aparecida; de Albuquerque, Felipe Neves; Schneider, Roberta Siuffo; Gimenez, Alinne; Pozzan, Roberto; Rocha, Ricardo Mourilhe; de Albuquerque, Denilson Campos

2016-01-01

Background Association between angiotensin-converting-enzyme (ACE) gene polymorphisms and different clinical and echocardiographic outcomes has been described in patients with heart failure (HF) and coronary artery disease. Studying the genetic profile of the local population with both diseases is necessary to assess the occurrence of that association. Objectives To assess the frequency of ACE gene polymorphisms in patients with ischemic HF in a Rio de Janeiro population, as well as its association with echocardiographic findings. Methods Genetic assessment of I/D ACE polymorphism in association with clinical, laboratory and echocardiographic analysis of 99 patients. Results The allele frequency was: 53 I alleles, and 145 D alleles. Genotype frequencies were: 49.5% DD; 47.48% DI; 3.02% II. Drug treatment was optimized: 98% on beta-blockers, and 84.8% on ACE inhibitors or angiotensin-receptor blocker. Echocardiographic findings: difference between left ventricular diastolic diameters (ΔLVDD) during follow-up: 2.98±8.94 (DD) vs. 0.68±8.12 (DI) vs. -11.0±7.00 (II), p=0.018; worsening during follow-up of the LV systolic diameter (LVSD): 65.3% DD vs. 19.0% DI vs. 0.0% II, p=0.01; of the LV diastolic diameter (LVDD): 65.3% DD vs. 46.8% DI vs. 0.0% II, p=0.03; and of the LV ejection fraction (LVEF): 67.3% DD vs. 40.4% DI vs. 33.3% II, p=0.024. Correlated with D allele: ΔLVEF, ΔLVSD, ΔLVDD. Conclusions More DD genotype patients had worsening of the LVEF, LVSD and LVDD, followed by DI genotype patients, while II genotype patients had the best outcome. The same pattern was observed for ΔLVDD. PMID:27812677

The interactive effects of mercury and selenium on metabolic profiles, gene expression and antioxidant enzymes in halophyte Suaeda salsa.

Science.gov (United States)

Liu, Xiaoli; Lai, Yongkai; Sun, Hushan; Wang, Yiyan; Zou, Ning

2016-04-01

Suaeda salsa is the pioneer halophyte in the Yellow River Delta and was consumed as a popular vegetable. Mercury has become a highly risky contaminant in the sediment of intertidal zones of the Yellow River Delta. In this work, we investigated the interactive effects of mercury and selenium in S. salsa on the basis of metabolic profiling, antioxidant enzyme activities and gene expression quantification. Our results showed that mercury exposure (20 μg L(-1)) inhibited plant growth of S. salsa and induced significant metabolic responses and altered expression levels of INPS, CMO, and MDH in S. salsa samples, together with the increased activities of antioxidant enzymes including SOD and POD. Overall, these results indicated osmotic and oxidative stresses, disturbed protein degradation and energy metabolism change in S. salsa after mercury exposures. Additionally, the addition of selenium could induce both antagonistic and synergistic effects including alleviating protein degradation and aggravating osmotic stress caused by mercury. © 2014 Wiley Periodicals, Inc.

CYP2B6, CYP2D6, and CYP3A4 catalyze the primary oxidative metabolism of perhexiline enantiomers by human liver microsomes.

Science.gov (United States)

Davies, Benjamin J; Coller, Janet K; Somogyi, Andrew A; Milne, Robert W; Sallustio, Benedetta C

2007-01-01

The cytochrome P450 (P450)-mediated 4-monohydroxylations of the individual enantiomers of the racemic antianginal agent perhexiline (PHX) were investigated in human liver microsomes (HLMs) to identify stereoselective differences in metabolism and to determine the contribution of the polymorphic enzyme CYP2D6 and other P450s to the intrinsic clearance of each enantiomer. The cis-, trans1-, and trans2-4-monohydroxylation rates of (+)- and (-)-PHX by human liver microsomes from three extensive metabolizers (EMs), two intermediate metabolizers (IMs), and two poor metabolizers (PMs) of CYP2D6 were measured with a high-performance liquid chromatography assay. P450 isoform-specific inhibitors, monoclonal antibodies directed against P450 isoforms, and recombinantly expressed human P450 enzymes were used to define the P450 isoform profile of PHX 4-monohydroxylations. The total in vitro intrinsic clearance values (mean +/- S.D.) of (+)- and (-)-PHX were 1376 +/- 330 and 2475 +/- 321, 230 +/- 225 and 482 +/- 437, and 63.4 +/- 1.6 and 54.6 +/- 1.2 microl/min/mg for the EM, IM, and PM HLMs, respectively. CYP2D6 catalyzes the formation of cis-OH-(+)-PHX and trans1-OH-(+)-PHX from (+)-PHX and cis-OH-(-)-PHX from (-)-PHX with high affinity. CYP2B6 and CYP3A4 each catalyze the trans1- and trans2-4-monohydroxylation of both (+)- and (-)-PHX with low affinity. Both enantiomers of PHX are subject to significant polymorphic metabolism by CYP2D6, although this enzyme exhibits distinct stereoselectivity with respect to the conformation of metabolites and the rate at which they are formed. CYP2B6 and CYP3A4 are minor contributors to the intrinsic P450-mediated hepatic clearance of both enantiomers of PHX, except in CYP2D6 PMs.

Glucocorticoid receptor polymorphism in obesity and glucose homeostasis.

Science.gov (United States)

Majer-Łobodzińska, Agnieszka; Adamiec-Mroczek, Joanna

2017-01-01

Glucocorticoid receptor (GR) activity plays a significant role in the etiology of obesity and is essential for glucose homeostasis, the development of hyperinsulinaemia and subsequent increased fat deposition. Several polymorphisms in the GR gene have been described, and at least three of them seem to be associated with altered glucocorticoid sensitivity and changes in glucose homeostasis, and other metabolic parameters. The N363S polymorphism has been associated with increased sensitivity to glucocorticoides, increased insulin response to dexamethasone and increased plasma glucose level. BclI polymorphism is associated with increased abdominal obesity, hyperinsulinaemia and increased insulin resistance. Another polymorphism, ER22/23EK, in contrast to the others, is associated with relative resistance to glucocoricides actions and more beneficial metabolic profile-lower insulin resistance level, decreased lower cardiovascular risk and subseuent prolongation of life time. More research is still needed to understand the mechanisms behind these associations at the molecular level.

CYP3A4 Mediates Oxidative Metabolism of the Synthetic Cannabinoid AKB-48.

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Holm, Niels Bjerre; Nielsen, Line Marie; Linnet, Kristian

2015-09-01

Synthetic cannabinoid designer drugs have emerged as drugs of abuse during the last decade, and acute intoxication cases are documented in the scientific literature. Synthetic cannabinoids are extensively metabolized, but our knowledge of the involved enzymes is limited. Here, we investigated the metabolism of N-(1-adamantyl)-1-pentyl-1H-indazole-3-carboxamide (AKB-48), a compound identified in herbal blends from 2012 and onwards. We screened for metabolite formation using a panel of nine recombinant cytochrome P450 (CYP) enzymes (CYP1A2, 2B6, 2C8, 2C9, 2C18, 2C19, 2D6, 2E1, and 3A4) and compared the formed metabolites to human liver microsomal (HLM) incubations with specific inhibitors against CYP2D6, 2C19, and 3A4, respectively. The data reported here demonstrate CYP3A4 to be the major CYP enzyme responsible for the oxidative metabolism of AKB-48, preferentially performing the oxidation on the adamantyl moiety. Genetic polymorphisms are likely not important with regard to toxicity given the major involvement of CYP3A4. Adverse drug-drug interactions (DDIs) could potentially occur in cases with co-intake of strong CYP3A4 inhibitors, e.g., HIV antivirals and azole antifungal agents.

Yinchenhao Decoction Ameliorates Alpha-Naphthylisothiocyanate Induced Intrahepatic Cholestasis in Rats by Regulating Phase II Metabolic Enzymes and Transporters

Directory of Open Access Journals (Sweden)

Ya-Xiong Yi

2018-05-01

Full Text Available Yinchenhao Decoction (YCHD, a famous traditional Chinese formula, has been used for treating cholestasis for 1000s of years. The cholagogic effect of YCHD has been widely reported, but its pharmacodynamic material and underlying therapeutic mechanism remain unclear. By using ultra-high-performance liquid chromatography (UHPLC-quadrupole time-of-flight mass spectrometry, 11 original active components and eight phase II metabolites were detected in rats after oral administration of YCHD, including three new phase II metabolites. And it indicated that phase II metabolism was one of the major metabolic pathway for most active components in YCHD, which was similar to the metabolism process of bilirubin. It arouses our curiosity that whether the metabolism process of YCHD has any relationship with its cholagogic effects. So, a new method for simultaneous quantitation of eight active components and four phase II metabolites of rhein, emodin, genipin, and capillarisin has been developed and applied for their pharmacokinetic study in both normal and alpha-naphthylisothiocyanate (ANIT-induced intrahepatic cholestasis rats. The results indicated the pharmacokinetic behaviors of most components of YCHD were inhibited, which was hypothesized to be related to different levels of metabolic enzymes and transporters in rat liver. So dynamic changes of intrahepatic enzyme expression in cholestasis and YCHD treated rats have been monitored by an UHPLC-tandem mass spectrometry method. The results showed expression levels of UDP-glucuronosyltransferase 1-1 (UGT1A1, organic anion-transporting polypeptide 1A4 (OATP1A4, multidrug resistance-associated protein 2 (MRP2, multidrug resistance protein 1, sodium-dependent taurocholate cotransporter, and organic anion-transporting polypeptide 1A2 were significantly inhibited in cholestasis rats, which would account for reducing the drug absorption and the metabolic process of YCHD in cholestatic rats. A high dose (12 g/kg of

Assessment of Mercaptopurine (6MP) Metabolites and 6MP Metabolic Key-Enzymes in Childhood Acute Lymphoblastic Leukemia

NARCIS (Netherlands)

Wojtuszkiewicz, A.; Barcelos, A.; Dubbelman, B.; Abreu, R.A. de; Brouwer, C.; Bökkerink, J.P.M.; Haas, V. de; Groot-Kruseman, H. de; Jansen, G.; Kaspers, G.L.; Cloos, J.; Peters, G.J.

2014-01-01

Pediatric acute lymphoblastic leukemia (ALL) is treated with combination chemotherapy including mercaptopurine (6MP) as an important component. Upon its uptake, 6MP undergoes a complex metabolism involving many enzymes and active products. The prognostic value of all the factors engaged in this

Novel role of a triglyceride-synthesizing enzyme: DGAT1 at the crossroad between triglyceride and cholesterol metabolism

NARCIS (Netherlands)

Sachdev, Vinay; Leopold, Christina; Bauer, Raimund; Patankar, Jay V.; Iqbal, Jahangir; Obrowsky, Sascha; Boverhof, Renze; Doktorova, Marcela; Scheicher, Bernhard; Goeritzer, Madeleine; Kolb, Dagmar; Turnbull, Andrew V.; Zimmer, Andreas; Hoefler, Gerald; Hussain, M. Mahmood; Groen, Albert K.; Kratky, Dagmar

2016-01-01

Acyl-CoA:diacylglycerol acyltransferase 1 (DGAT1) is a key enzyme in triacylglycerol (TG) biosynthesis. Here we show that genetic deficiency and pharmacological inhibition of DGAT1 in mice alters cholesterol metabolism. Cholesterol absorption, as assessed by acute cholesterol uptake, was

Polymorphisms of cytochrome P450 2B6 (CYP2B6) in cynomolgus and rhesus macaques.

Science.gov (United States)

Uno, Yasuhiro; Uehara, Shotaro; Yamazaki, Hiroshi

2018-02-22

Cytochrome P450 2B6 (CYP2B6) is an important drug-metabolizing enzyme and is expressed in liver. Although human CYP2B6 variants account for variable enzyme properties among individuals and populations, CYP2B6 genetic variants have not been investigated in cynomolgus macaques, widely used in drug metabolism studies. CYP2B6 was resequenced in 120 cynomolgus macaques and 23 rhesus macaques by direct sequencing. Twenty-three non-synonymous variants were found, of which 12 and 3 were unique to cynomolgus macaques and rhesus macaques, respectively. By functional characterization using the 14 variant proteins, 8 variants (V114I, R253C, M435I, V459M, L465P, C475S, R487C, and R487H) showed different rate (>1.5-fold) of testosterone 16β-hydroxylation to wild type. However, the four variants (M435I, L465P, C475S, and R487H) were analyzed in liver microsomes, and the catalytic rates were not substantially different from wild type. Macaque CYP2B6 was polymorphic, and the genotype could partly account for variable enzyme activities of macaque CYP2B6. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Diversity of apolipoprotein E genetic polymorphism significance on cardiovascular risk is determined by the presence of metabolic syndrome among hypertensive patients.

Science.gov (United States)

Teixeira, Andrei Alkmim; Marrocos, Mauro Sergio; Quinto, Beata Marie Redublo; Dalboni, Maria Aparecida; Rodrigues, Cassio Jose de Oliveira; Carmona, Silmara de Melo; Kuniyoshi, Mariana; Batista, Marcelo Costa

2014-11-20

Hypertension has a significant relevance as a cardiovascular risk factor. A consistent increase on world's Metabolic Syndrome (MetS) incidence has been associated with an epidemic cardiovascular risk in different populations. Dislipidemia plays a major role determining the epidemic CV burden attributed to MetS. Apolipoprotein E (ApoE) is involved on cholesterol and triglycerides metabolism regulation. Once ApoE polymorphism may influence lipid metabolism, it is possible that it brings on individual susceptibility consequences for the development of MetS and cardiovascular risk. The objective of the study is to measure the discriminatory power of ApoE polymorphism in determining cardiovascular risk stratification based on the presence MetS in a cohort of hypertensive patients. It was enrolled 383 patients, divided in two groups, classified by MetS presence (IDF criteria): Group 1: 266 patients with MetS (MetS +) and Group 2: 117 patients without Mets (MetS -). Patient's data were collected by clinical evaluation, physical exam, file reviews and laboratory testing. Polymorphic ApoE analysis was performed by PCR amplification. Groups were compared on clinical and laboratory characteristics as well as allele and genotype distribution towards ApoE polymorphism. Mets CVD prevalence was analysed according to E4 allele prevalence. The results evidenced 184 men (48%), 63,7% whites, 45,1% diabetics and 11,7% of patients were smokers. Mean age was 64,0 ± 12,0 years. When genotypic distribution was analyzed, E3/3 genotype and E3 allele frequencies were more prevalent. Among patients with MetS, we observed an independent association between CVD prevalence and E4 allele frequency (OR 2.42 (1.17- 5.0, p < 0,05)). On the opposite direction, in those without MetS, there was lesser CVD burden in E4 allele carriers (OR 0,14 (0,02-0,75)). These associations remained significant even after confounding factor corrections. The results presented demonstrate that the association

Effect of Chromium(VI Toxicity on Enzymes of Nitrogen Metabolism in Clusterbean (Cyamopsis tetragonoloba L.

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Punesh Sangwan

2014-01-01

Full Text Available Heavy metals are the intrinsic component of the environment with both essential and nonessential types. Their excessive levels pose a threat to plant growth and yield. Also, some heavy metals are toxic to plants even at very low concentrations. The present investigation (a pot experiment was conducted to determine the affects of varying chromium(VI levels (0.0, 0.5, 1.0, 2.0, and 4.0 mg chromium(VI kg−1 soil in the form of potassium dichromate on the key enzymes of nitrogen metabolism in clusterbean. Chromium treatment adversely affect nitrogenase, nitrate reductase, nitrite reductase, glutamine synthetase, and glutamate dehydrogenase in various plant organs at different growth stages as specific enzyme activity of these enzymes decreased with an increase in chromium(VI levels from 0 to 2.0 mg chromium(VI kg−1 soil and 4.0 mg chromium(VI kg−1 soil was found to be lethal to clusterbean plants. In general, the enzyme activity increased with advancement of growth to reach maximum at flowering stage and thereafter decreased at grain filling stage.

Lack of relationship between an insertion/deletion polymorphism in the angiotensin I-converting enzyme gene and diabetic nephropathy and proliferative retinopathy in IDDM patients

DEFF Research Database (Denmark)

Tarnow, L; Cambien, Francois; Rossing, P

1995-01-01

Genotypic abnormalities of the renin-angiotensin system have been suggested as a risk factor for the development of diabetic nephropathy and proliferative retinopathy. We studied the relationship between an insertion(I)/deletion (D) polymorphism in the angiotensin-converting enzyme (ACE) gene...... (40%) had proliferative retinopathy, and 67 patients (17%) had no diabetic retinopathy. There was no difference in genotype distribution between IDDM patients with diabetic nephropathy and those with normalbuminuria: 63 (32%)/95 (48%)/40 (20%) vs. 67 (35%)/77 (41%)/46 (24%) had DD/ID/II genotypes...... by ACE/ID polymorphism, mean arterial blood pressure, and glomerular filtration rate (r2 = 0.30, P retinopathy and those without diabetic retinopathy: 52 (34%)/74 (48%)/29 (19%) vs. 26 (39%)/25 (37...

Genetic polymorphisms in one-carbon metabolism: associations with CpG island methylator phenotype (CIMP) in colon cancer and the modifying effects of diet.

Science.gov (United States)

Curtin, Karen; Slattery, Martha L; Ulrich, Cornelia M; Bigler, Jeannette; Levin, Theodore R; Wolff, Roger K; Albertsen, Hans; Potter, John D; Samowitz, Wade S

2007-08-01

This study investigated associations between CpG island methylator phenotype (CIMP) colon cancer and genetic polymorphisms relevant to one-carbon metabolism and thus, potentially the provision of methyl groups and risk of colon cancer. Data from a large, population-based case-control study (916 incident colon cancer cases and 1,972 matched controls) were used. Candidate polymorphisms in methylenetetrahydrofolate reductase (MTHFR), thymidylate synthase (TS), transcobalamin II (TCNII), methionine synthase (MTR), reduced folate carrier (RFC), methylenetetrahydrofolate dehydrogenase 1 (MTHFD1), dihydrofolate reductase (DHFR) and alcohol dehydrogenase 3 (ADH3) were evaluated. CIMP- or CIMP+ phenotype was based on five CpG island markers: MINT1, MINT2, MINT31, p16 and MLH1. The influence of specific dietary factors (folate, methionine, vitamin B(12) and alcohol) on these associations was also analyzed. We hypothesized that polymorphisms involved in the provision of methyl groups would be associated with CIMP+ tumors (two or more of five markers methylated), potentially modified by diet. Few associations specific to CIMP+ tumors were observed overall, which does not support the hypothesis that the provision of methyl groups is important in defining a methylator phenotype. However, our data suggest that genetic polymorphisms in MTHFR 1,298A > C, interacting with diet, may be involved in the development of highly CpG-methylated colon cancers. AC and CC genotypes in conjunction with a high-risk dietary pattern (low folate and methionine intake and high alcohol use) were associated with CIMP+ (OR = 2.1, 95% CI = 1.3-3.4 versus AA/high risk; P-interaction = 0.03). These results provide only limited support for a role of polymorphisms in one-carbon metabolism in the etiology of CIMP colon cancer.

Apa-I polymorphism in VDR gene is related to metabolic syndrome in polycystic ovary syndrome: a cross-sectional study.

Science.gov (United States)

Santos, Betânia Rodrigues; Lecke, Sheila Bunecker; Spritzer, Poli Mara

2018-04-18

Polycystic ovary syndrome (PCOS) is a common endocrine disorder determined by polygenic traits as well as environmental factors. Lower vitamin D levels have been detected in PCOS women and related to hormone and metabolic disturbances. Vitamin D acts in tissues through the vitamin D receptor (VDR). VDR gene variants have been associated with worse metabolic profile in the general population. We investigated the genotype and haplotype distribution of the Bsm-I (rs1544410), Apa-I (rs7975232), and Taq-I (rs731236) VDR gene polymorphisms in PCOS and non-hirsute women from southern Brazil. We further investigated the associations of these gene variants and their haplotypes with PCOS, vitamin D levels, and metabolic abnormalities, including the metabolic syndrome (MetS). A group of 191 women with PCOS (Rotterdam criteria) and 100 non-hirsute controls with regular ovulatory cycles were genotyped for all polymorphisms by real-time PCR, with allelic discrimination assays. MetS and the cutoffs for its isolated components were defined in accordance with the Joint Scientific Statement. Women with PCOS were younger and had significantly higher BMI and total testosterone levels than controls (p Apa-I entailed higher risk of MetS in PCOS (OR: 2.133; 95% CI 1.020-4.464, p = 0.042), and was associated with higher systolic blood pressure (p = 0.009), total cholesterol (p = 0.040), and LDL-cholesterol (p = 0.038) in both PCOS and control groups (two-way ANOVA). The frequencies of VDR haplotypes were similar in PCOS and control women. The present results suggest that the Apa-I variant in VDR gene may be associated with MetS in southern Brazilian women with PCOS, and with blood pressure, total cholesterol, and LDL-c in women with and without PCOS.

Studies on cell-free metabolism: ethanol production by a yeast glycolytic system reconstituted from purified enzymes

Energy Technology Data Exchange (ETDEWEB)

Welch, P; Scopes, R K

1985-07-01

A reconstituted glycolytic system has been established from individually purified enzymes to simulate the conversion of glucose to ethanol plus CO/sub 2/ by yeast. Sustained and extensive conversion occurred provided that input of glucose matched the rate of ATP degradation appropriately. ATPase activity could be replaced by arsenate, which uncoupled ATP synthesis from glycolysis. The mode of uncoupling was investigated, and it was concluded that the artificial intermediate, 1-arseno-3-phosphoglycerate, has a half-life of no more than a few milliseconds. Arsenate at 4 mM concentration could simulate the equivalent of 10 ..mu..mol/ml min. of ATPase activity. The reconstituted enzyme system was capable of totally degrading one M (18% w/v) glucose in 8 hours giving 9% (w/v) ethanol. The levels of metabolites during metabolism were measured to detect rate-limiting steps. The successful operation of the reconstituted enzyme system demonstrates that it is possible to carry out complex chemical transformations with multiple enzyme systems in vitro. 36 references.

Association of Apolipoprotein A5 Gene   −1131T>C Polymorphism with the Risk of Metabolic Syndrome in Korean Subjects

Directory of Open Access Journals (Sweden)

Kwang Hoon Song

2013-01-01

Full Text Available We assessed the associations between the APOA5  −1131T>C polymorphism and lipid parameters and other risk factors of the metabolic syndrome in Korean subjects. A total of 2,901 participants from 20 oriental medical hospitals in Korea were enrolled between 2006 and 2011. According to the modified National Cholesterol Education Program Adult Treatment Panel III definitions, subjects were classified into the metabolic syndrome group and control group. The APOA5  −1131T>C genotype was significantly associated with serum high-density lipoprotein cholesterol levels (effect = − 1.700 mg/dL, P=6.550-E07 in the total study population after adjustment for differences in age and gender. The association of the APOA5  −1131T>C genotype with serum log-transformed triglyceride was also significant in an additive genetic model (effect = 0.056 mg/dL, P=2.286E-19. After adjustment for age and gender, we determined that the odds ratio for the occurrence of the metabolic syndrome was 1.322 for C-allele carriers in the additive model (95% CI = [1.165 − 1.501], P=1.48E-05. In the current study, we demonstrated that the APOA5  −1131T>C polymorphism is associated with the metabolic syndrome because of its remarkable effect on serum triglyceride levels in Korean subjects.

Fatty acid CoA ligase-4 gene polymorphism influences fatty acid metabolism in metabolic syndrome, but not in depression.

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Zeman, Miroslav; Vecka, Marek; Jáchymová, Marie; Jirák, Roman; Tvrzická, Eva; Stanková, Barbora; Zák, Ales

2009-04-01

The composition of polyunsaturated fatty acids (PUFAs) in cell membranes and body tissues is altered in metabolic syndrome (MetS) and depressive disorder (DD). Within the cell, fatty acid coenzyme A (CoA) ligases (FACLs) activate PUFAs by esterifying with CoA. The FACL4 isoform prefers PUFAs (arachidonic and eicosapentaenoic acid) as substrates, and the FACL4 gene is mapped to Xq23. We have analyzed the association between the common single nucleotide polymorphism (SNP) (rs1324805, C to T substitution) in the first intron of the FACL4 gene and MetS or DD. The study included 113 healthy subjects (54 Males/59 Females), 56 MetS patients (34M/22F) and 41 DD patients (7M/34F). In MetS group, T-carriers and patients with CC or C0 (CC/C0) genotype did not differ in the values of metabolic indices of MetS and M/F ratio. Nevertheless, in comparison with CC/C0, the T-allele carriers were characterized by enhanced unfavorable changes in fatty acid metabolism typical for MetS: higher content of dihomogammalinolenic acid (P phosphatidylcholine (PC) (P = 0.052), lower index of Delta5 desaturation (P insulin, conjugated dienes and index of insulin resistance, but showed no significant association with the studied SNP. The present study shows that the common SNP (C to T substitution) in the first intron of the FACL4 gene is associated with altered FA composition of plasma phosphatidylcholines in patients with MetS.

Effects of prolonged recombinant human erythropoietin administration on muscle membrane transport systems and metabolic marker enzymes

DEFF Research Database (Denmark)

Juel, C; Thomsen, J J; Rentsch, R L

2007-01-01

on the expression of muscle membrane transport proteins. Likewise, improvements in performance may involve upregulation of metabolic enzymes. Since Epo is known to augment performance we tested the effect of rHuEpo on some marker enzymes that are related to aerobic capacity. For these purposes eight subjects...... performance by approximately 54%. Membrane transport systems and carbonic anhydrases involved in pH regulation remained unchanged. Of the Na(+), K(+)-pump isoforms only the density of the alpha2 subunit was decreased (by 22%) after treatment. The marker enzymes cytochrom c and hexokinase remained unchanged......Adaptations to chronic hypoxia involve changes in membrane transport proteins. The underlying mechanism of this response may be related to concomitant occurring changes in erythropoietin (Epo) levels. We therefore tested the direct effects of recombinant human erythropoietin (rHuEpo) treatment...

A novel polymorphism of resistin gene and its association with meat ...

African Journals Online (AJOL)

Searching for candidate gene polymorphisms and their relationship with meat quality traits is an important issue for Bos taurus industry. In this study, we evaluated polymorphism of resistin (RETN) gene involved in energy metabolism. Using the polymerase chain reaction-single strand conformation polymorphism ...

Effects of dibutyl phthalate on lipid metabolism and drug metabolising enzyme system in rats

International Nuclear Information System (INIS)

Arakaki, Mitsuo; Ariyoshi, Toshihiko.

1976-01-01

Effects of dibutyl phthalate (DBP) on the liver constituents and the drug metabolizing enzyme system were investigated in rats. 1. In the experiments at a single oral dose of DBP (630 or 1260 mg/kg), the glycogen content was decreased only at the high dose, but no effects were observed on the contents of glycogen, triglyceride, microsomal protein and cytochromes, and on the activities of drug metabolizing enzymes. 2. In the repeated oral dose of DBP (630 or 1260 mg/kg/day) for 5 days, the ratio of liver weight to body weight was increased in both female and male rats, whereas the increases of cytochrome P-450 content and aniline hydroxylase activity were noted only in male rats. However, the contents of liver triglyceride, phospholipids, and cholesterol were unchanged. On the other hand, serum cholesterol content which showed the tendency to be decreased at the low dose was significantly decreased at the high dose. 3. In the incorporation of 1- 14 C-acetate into liver and serum lipids after repeated oral dose of DBP (630 mg/kg/day) for 5 days in male rats, the incorporation into triglyceride showed tendency to be increased, whereas the incorporation into cholesterol and cholesterol ester remained unchanged in vivo and in vitro. (auth.)

PAH-DNA adducts in environmentally exposed population in relation to metabolic and DNA repair gene polymorphisms

Energy Technology Data Exchange (ETDEWEB)

Binkova, Blanka [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic); Chvatalova, Irena [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic); Lnenickova, Zdena [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic); Milcova, Alena [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic); Tulupova, Elena [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic); Cancer Biomarkers and Prevention Group, Biocentre, University of Leicester (United Kingdom); Farmer, Peter B. [Cancer Biomarkers and Prevention Group, Biocentre, University of Leicester (United Kingdom); Sram, Radim J. [Laboratory of Genetic Ecotoxicology, Institute of Experimental Medicine AS CR and Health Institute of Central Bohemia, Videnska 1083, 14220 Prague (Czech Republic)]. E-mail: sram@biomed.cas.cz

2007-07-01

Epidemiologic studies indicate that prolonged exposure to particulate air pollution may be associated with increased risk of cardiovascular diseases and cancer in general population. These effects may be attributable to polycyclic aromatic hydrocarbons (PAHs) adsorbed to respirable air particles. It is expected that metabolic and DNA repair gene polymorphisms may modulate individual susceptibility to PAH exposure. This study investigates relationships between exposure to PAHs, polymorphisms of these genes and DNA adducts in group of occupationally exposed policemen (EXP, N = 53, males, aged 22-50 years) working outdoors in the downtown area of Prague and in matched 'unexposed' controls (CON, N = 52). Personal exposure to eight carcinogenic PAHs (c-PAHs) was evaluated by personal samplers during working shift prior to collection of biological samples. Bulky-aromatic DNA adducts were analyzed in lymphocytes by {sup 32}P-postlabeling assay. Polymorphisms of metabolizing (GSTM1, GSTP1, GSTT1, EPHX1, CYP1A1-MspI) and DNA repair (XRCC1, XPD) genes were determined by PCR-based RFLP assays. As potential modifiers and/or cofounders, urinary cotinine levels were analyzed by radioimmunoassay, plasma levels of vitamins A, C, E and folates by HPLC, cholesterol and triglycerides using commercial kits. During the sampling period ambient particulate air pollution was as follows: PM10 32-55 {mu}g/m{sup 3}, PM2.5 27-38 {mu}g/m{sup 3}, c-PAHs 18-22 ng/m{sup 3}; personal exposure to c-PAHs: 9.7 ng/m{sup 3} versus 5.8 ng/m{sup 3} (P < 0.01) for EXP and CON groups, respectively. The total DNA adduct levels did not significantly differ between EXP and CON groups (0.92 {+-} 0.28 adducts/10{sup 8} nucleotides versus 0.82 {+-} 0.23 adducts/10{sup 8} nucleotides, P = 0.065), whereas the level of the B[a]P-'like' adduct was significantly higher in exposed group (0.122 {+-} 0.036 adducts/10{sup 8} nucleotides versus 0.099 {+-} 0.035 adducts/10{sup 8} nucleotides, P = 0

Insertion/Deletion Polymorphisms and Serum Angiotensin-converting Enzyme Levels in Iranian Patients with Sarcoidosis

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JAVADI, Alireza; SHAMAEI, Masoud; ZAREI, Masoud; REZAEIAN, Lida; KIANI, Arda; ABEDINI, Atefeh

2016-01-01

Background: Sarcoidosis is a multisystem inflammatory disease of unknown origin with characterization of small granulomas. Angiotensin-converting enzyme (ACE) is a pathophysiologic marker of sarcoidosis. We present the ACE insertion/deletion (I/D) polymorphism in correlation with serum ACE level in Iranian patients with sarcoidosis. Methods: From Jan 2014 to Jan 2015, 102 Iranian patients who histopathologically diagnosed for sarcoidosis and 192 healthy age and sex-matched controls were recruited. PCR was used for detection of I/D polymorphism in ACE gene. Results: Frequency of II/ID/DD genotype in sarcoidosis disease was 17%, 35.5%, and 47.1%, respectively. The frequency of D allele was 0.65. A significant association between I/D genotypes and mean of sACE level was seen (DD=85.2±22.9, P<0.001). More frequent genotype in sarcoidosis patients was DD (47%), ID genotype (45.9%) was found more in controls. Logistic regression analysis adjusting age and sex showed that ID to II (OR=0.35, 95%CI=0.17–0.73, P=0.005) and DD to II (OR=2.11, 95%CI=0.98–4.54, P=0.05) could be considered as a predictor factor for the disease activity. No significant model for men in sarcoidosis group was seen, while women with II/ID were associated with a reduced risk for the disease. Conclusion: Although more regional studies with appropriate statistical scale must be done to provide a better diagnosis and prognostic tool for this disease, this study demonstrates that ID and DD genotype could be predictive factors for sarcoidosis. PMID:28032065

Prevalence of alpha actinin-3 gene (ACTN3) R577X and angiotensin converting enzyme (ACE) insertion / deletion gene polymorphisms in national and amateur Turkish athletes.

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Eroğlu, Onur; Zileli, Rayif; Nalbant, M Ali; Ulucan, Korkut

2018-04-30

Studies to date showed the importance of alpha- actinin-3 (ACTN3) R577X and angiotensin converting enzyme (ACE) ID polymorphisms on determining athletic performance. Therefore, in this study, we aimed to examine polymorphisms given to Turkish athletes and compare them with sedentary individuals. Genomic DNAs were extracted from peripheral blood by using commercially available DNA isolation kit (Macherey-Nagel, NucleoSpin®, Germany). For this study, a total of 84 volunteers (23 national athletes, 27 amateur athletes and 34 sedentary controls) was recruited.  ACE ID genotypes were determined by conventional polymerase chain reaction, and ACTN3 R577X polymorphisms by polymerase chain reaction- restriction fragment length polymorphism methodology.   In ACTN3 R577X polymorphism, RX was the dominating genotype, and we detected no RR genotype in national athletes. (no RR genotype was detected in national athletes) X allele is more frequent in national athletes and R allele was more frequent in both amateur athletes and control group. II genotype was more frequent in national athletes and in control group, whereas DD genotype was more frequent in amateur athletes for ACE ID polymorphism. When we consider alleles, D allele was found more frequently in amateur athletes and control group whereas I allele was more frequent in national athletes in ACE ID polymorphism. For ACTN3, X allele was superior to R allele. ACTN3 R577X and ACE ID polymorphisms were important biomarkers in determining athletic performance. However, our results in Turkish athletes suggest that ACE D allele and ACTN3 X alleles may be beneficial to athletes potentially, regardless of the distance they perform.

An Angiotensin I Converting Enzyme Polymorphism Is Associated with Clinical Phenotype When Using Differentiation-Syndrome to Categorize Korean Bronchial Asthma Patients

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Sung-ki Jung

2011-01-01

Full Text Available In this study, genetic analysis was conducted to investigate the association of angiotensin I converting enzyme (ACE gene polymorphism with clinical phenotype based on differentiation-syndrome of bronchial asthma patients. Differentiation-syndrome is a traditional Korean medicine (TKM theory in which patients are classified into a Deficiency Syndrome Group (DSG and an Excess Syndrome Group (ESG according to their symptomatic classification. For this study, 110 participants were evaluated by pulmonary function test. Among them, 39 patients were excluded because they refused genotyping. Of the remaining patients, 52 with DSG of asthma (DSGA and 29 with ESG of asthma (ESGA, as determined by the differentiation-syndrome techniques were assessed by genetic analysis. ACE insertion/deletion (I/D polymorphism analysis was conducted using polymerase chain reaction (PCR. Student's t, chi-square, Fisher and Hardy-Weinberg equilibrium tests were used to compare groups. No significant differences in pulmonary function were observed between DSGA and ESGA. The genotypic frequency of ACE I/D polymorphism was found to differ slightly between DSGA and ESGA (P = .0495. However, there were no significant differences in allelic frequency observed between DSGA and ESGA (P = .7006, OR = 1.1223. Interestingly, the allelic (P = .0043, OR = 3.4545 and genotypic (P = .0126 frequencies of the ACE I/D polymorphism in female patients differed significantly between DSGA and ESGA. Taken together, the results presented here indicate that the symptomatic classification of DSGA and ESGA by differentiation-syndrome in Korean asthma patients could be useful in evaluation of the pathogenesis of bronchial asthma.

ACE I/D polymorphism in Indian patients with hypertrophic cardiomyopathy and dilated cardiomyopathy

DEFF Research Database (Denmark)

Rai, Taranjit Singh; Dhandapany, Perundurai Subramaniam; Ahluwalia, Tarun Veer Singh

2008-01-01

The study was carried to determine the association of angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism with the risk of hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and restrictive cardiomyopathy (RCM).......The study was carried to determine the association of angiotensin converting enzyme (ACE) insertion/deletion (I/D) polymorphism with the risk of hypertrophic cardiomyopathy (HCM), dilated cardiomyopathy (DCM), and restrictive cardiomyopathy (RCM)....

Adaptation of red cell enzymes and intermediates in metabolic disorders.

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Goebel, K M; Goebel, F D; Neitzert, A; Hausmann, L; Schneider, J

1975-01-01

The metabolic activity of the red cell glycolytic pathway hexose monophosphate shunt (HMP) with dependent glutathione system was studied in patients with hyperthyroidism (n = 10), hyperlipoproteinemia (n = 16), hypoglycemia (n = 25) and hyperglycemia (n = 23). In uncontrolled diabetics and patients with hyperthyroidism the mean value of glucose phosphate isomerase (GPI), glucose-6-phosphate dehydrogenase (G-6-PD), glutathione reductase (GR) was increased, whereas these enzyme activities were reduced in patients with hypoglycemia. Apart from a few values of hexokinase (HK) which were lower than normal the results in hyperlipoproteinemia patients remained essentially unchanged, including the intermediates such as 2,3-diphosphoglycerate (2,3-DPG), adenosine triphosphate (ATP) and reduced glutathione (GSH). While increased rates of 2,3-DPG and ATP in hypoglycemia patients were obtained, these substrates were markedly reduced in diabetics.

Association of N-acetyltransferase-2 and glutathione S-transferase polymorphisms with idiopathic male infertility in Vietnam male subjects.

Science.gov (United States)

Trang, Nguyen Thi; Huyen, Vu Thi; Tuan, Nguyen Thanh; Phan, Tran Duc

2018-04-25

N-acetyltransferase-2 (NAT2) and Glutathione S-transferases (GSTs) are phase-II xenobiotic metabolizing enzymes participating in detoxification of toxic arylamines, aromatic amines, hydrazines and reactive oxygen species (ROS), which are produced under oxidative and electrophile stresses. The purpose of this research was to investigate whether two common single-nucleotide polymorphisms (SNP) of NAT2 (rs1799929, rs1799930) and GSTP1 (rs1138272, rs1695) associated with susceptibility to idiopathic male infertility. A total 300 DNA samples (150 infertile patients and 150 healthy control) were genotyped for the polymorphisms by ARMS - PCR. We revealed a significant association between the NAT2 variant genotypes (CT + TT (rs1799929), (OR: 3.74; p male infertility in subjects from Vietnam. This pilot study is the first (as far as we know) to reveal that polymorphisms of NAT2 (rs1799929, rs1799930) and GSTP1 (rs1138272, rs1695) are some novel genetic markers for susceptibility to idiopathic male infertility. Copyright © 2018 Elsevier B.V. All rights reserved.

Evolution of a flipped pathway creates metabolic innovation in tomato trichomes through BAHD enzyme promiscuity.

Science.gov (United States)

Fan, Pengxiang; Miller, Abigail M; Liu, Xiaoxiao; Jones, A Daniel; Last, Robert L

2017-12-12

Plants produce hundreds of thousands of structurally diverse specialized metabolites via multistep biosynthetic networks, including compounds of ecological and therapeutic importance. These pathways are restricted to specific plant groups, and are excellent systems for understanding metabolic evolution. Tomato and other plants in the nightshade family synthesize protective acylated sugars in the tip cells of glandular trichomes on stems and leaves. We describe a metabolic innovation in wild tomato species that contributes to acylsucrose structural diversity. A small number of amino acid changes in two acylsucrose acyltransferases alter their acyl acceptor preferences, resulting in reversal of their order of reaction and increased product diversity. This study demonstrates how small numbers of amino acid changes in multiple pathway enzymes can lead to diversification of specialized metabolites in plants. It also highlights the power of a combined genetic, genomic and in vitro biochemical approach to identify the evolutionary mechanisms leading to metabolic novelty.

Association between methylene tetrahydrofolate reductase gene C677T polymorphism with preeclampsia in south-east of Iran

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Mohsen Saravani

2011-12-01

Full Text Available Background: Preeclampsia (PE is a serious problem of pregnancy and its etiology is still unknown. There are some evidence that vascular complications play an important role in development of PE. Methylenetetrahydrofolate reductase (MTHFR is a key enzyme in folate metabolism and the C677T polymorphism of the MTHFR gene is associated with decreased MTHFR activity. The aim of this study was to evaluate the relationship between MTHFR gene C677T polymorphism with PE development in south-east of Iran.Materials and method: This study was performed in 106 preeclamptic pregnant women and 107 control individuals. The C677T polymorphism of the MTHFR gene was determined by PCR-RFLP method. Results: The CC, CT and TT genotypes frequency of C677T polymorphism of MTHFR gene were 77, 22 and 1 percent in preeclamptic women and 73, 19.5 and 7.5 percent in control group. They were not significantly different (p=0.06. However, the frequency of TT genotype was significantly higher in control group (OR=8.5; 95% CI 1.1-71; p=.018. There was not any significant difference in T allele distribution between preeclamptic women (12% and control group (17%. Conclusion: Our results showed that there was not any correlation between the C677T polymorphism and PE but the TT genotype of C677T polymorphism seems to be a protective factor for preeclampsia

Frequency Of C3435 Mdr1 And A6896g Cyp3a5 Single Nucleotide Polymorphism in an Iranian Population and Comparison with Other Ethnic Groups

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N. AZARPIRA

2006-11-01

Full Text Available Background:It is well recognized that different patients respond in different ways to medications. The inter-individual variations are greater than the intera- individual variations,a finding consistent with the notion that inheritance is a determinant of drug responses. The recent identification of genetic polymorphisms in drug-metabolizing enzymes and drug transporters led to the hypothesis that genetic factors may be implicated in this interindividual variation. Single nucleotide polymorphism in common metabolic pathway,cytochrome P450 and common transporter,multidrug resistance-1 gene are two important sites that might involve clinically significant genetic variations. Ethnicity greatly influences these genetic polymorphism distributions. Methods: We studied the inheritance patterns of polymorphisms for MDR1 and CYP3A5 genes in the Iranian population and compared its genotype and allele frequencies with 3 different ethnic groups: Caucasian (United Kingdom, Chinese and Japanese. Results: We found striking differences in the distribution of MDR allelic variants between Iranian,Japanese and Chinese (p<0.02 and similar between the Iranian and Caucasian population.(p=0.06.Almost 50% of Iranian and Caucasian individuals were homozygous carriers of the variant T allele compared with 32% of the Japanese and 43% of the Chinese (p<0.02.More than half of Iranian subjects have at least one T allele,with lower P-gp level in small intestine.We also noted dramatic differences in the CYP3A5 alleles and genotypes distribution between Iranian subjects with other compared populations.99% of Iranian individuals were homozygous carriers of the variant G allele compared with about 70% of the Chinese and Japanese and 19% of the Caucasian population. The G/G genotype has a very low level of active cytochrome P450 enzyme.Conclusion:Our results emphasize the role of ethnicity in interindividual variability of the pharmacokinetic and pharmacodynamic characteristics

Influence of 677 C→T Polymorphism of Methylenetetrahydrofolate Reductase on Medium-Term Prognosis after Acute Coronary Syndromes

OpenAIRE

García-Pinilla, José M.; Espinosa-Caliani, Salvador; Jiménez-Navarro, Manuel; Gómez-Doblas, Juan J.; Cabrera-Bueno, Fernando; Reyes-Engel, Armando; de Teresa-Galván, Eduardo

2007-01-01

Various common genotypes of the polymorphism 677 C→T of the methylenetetrahydrofolate reductase enzyme result in lower activity of the enzyme and in a subsequent increase in homocysteine levels. Many studies have analyzed the connection between this polymorphism and the beginning of coronary artery disease. However, conclusions have been controversial, and evidence of a connection between this polymorphism and the prognosis of coronary artery disease has been poorly evaluated.

Intrinsic Xenobiotic Metabolizing Enzyme Activities in Early Life Stages of Zebrafish (Danio rerio).

Science.gov (United States)

Otte, Jens C; Schultz, Bernadette; Fruth, Daniela; Fabian, Eric; van Ravenzwaay, Bennard; Hidding, Björn; Salinas, Edward R

2017-09-01

Early life stages of zebrafish (Danio rerio, zf) are gaining attention as an alternative invivo test system for drug discovery, early developmental toxicity screenings and chemical testing in ecotoxicological and toxicological testing strategies. Previous studies have demonstrated transcriptional evidence for xenobiotic metabolizing enzymes (XME) during early zf development. However, elaborate experiments on XME activities during development are incomplete. In this work, the intrinsic activities of representative phase I and II XME were monitored by transformation of putative zf model substrates analyzed using photometry and high pressure liquid chromatography techniques. Six different defined stages of zf development (between 2.5 h postfertilization (hpf) to 120 hpf) were investigated by preparing a subcellular fraction from whole organism homogenates. We demonstrated that zf embryos as early as 2.5 hpf possess intrinsic metabolic activities for esterase, Aldh, Gst, and Cyp1a above the methodological detection limit. The activities of the enzymes Cyp3a and Nat were measurable during later stages in development. Activities represent dynamic patterns during development. The role of XME activities revealed in this work is relevant for the assessing toxicity in this test system and therefore contributes to a valuable characterization of zf embryos as an alternative testing organism in toxicology. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Myeloperoxidase polymorphism, menopausal status, and breast cancer risk: an update meta-analysis.

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Xue Qin

Full Text Available Myeloperoxidase (MPO is a metabolic/oxidative lysosomal enzyme secreted by reactive neutrophils at the sites of inflamed organs and tissues during phagocytosis. MPO has been either directly or indirectly linked to neoplasia, which is a well-established risk factor for many types of cancer. A large number of studies have reported the role of MPO G-463A polymorphism regarding breast-cancer risk. However, the published findings are inconsistent. Therefore, we conducted a meta-analysis to determine more precise estimations for the relationship. Eligible studies were identified by searching several electronic databases for relevant reports published before June 2012. According to the inclusion criteria and exclusion criteria, a total of five eligible studies were included in the pooled analyses. When the five eligible studies concerning MPO G-463A polymorphism were pooled into this meta-analysis, there was no evidence found for a significant association between MPO G-463A polymorphism and breast-cancer risk in any genetic model. We also categorized by ethnicity (Caucasian or Asian for subgroup analysis; according to this subgroup analysis, we found no significant association between MPO G-463A polymorphism and breast-cancer risk in any genetic model. However, in the stratified analysis for the premenopausal group, women carrying the AA genotype were found to have a significantly reduced risk (OR = 0.56, 95% CI 0.34-0.94, p = 0.027. Under the recessive model, there was a significant association between MPO G-463A polymorphism and breast-cancer risk (OR = 0.57, 95% CI 0.34-0.93, p = 0.025. We conclude that MPO-G463A polymorphism might not be a good predictor of breast-cancer risk, though menopausal status modified women's risk of developing breast cancer.

Single-nucleotide polymorphism in the 5-α-reductase gene (SRD5A2) is associated with increased prevalence of metabolic syndrome in chemotherapy-treated testicular cancer survivors.

Science.gov (United States)

Boer, Hink; Westerink, Nico-Derk L; Altena, Renske; Nuver, Janine; Dijck-Brouwer, D A Janneke; van Faassen, Martijn; Klont, Frank; Kema, Ido P; Lefrandt, Joop D; Zwart, Nynke; Boezen, H Marike; Smit, Andries J; Meijer, Coby; Gietema, Jourik A

2016-02-01

Chemotherapy-treated testicular cancer survivors are at risk for development of the metabolic syndrome, especially in case of decreased androgen levels. Polymorphisms in the gene encoding steroid 5-α-reductase type II (SRD5A2) are involved in altered androgen metabolism. We investigated whether single-nucleotide polymorphisms (SNPs) rs523349 (V89L) and rs9282858 (A49T) in SRD5A2 are associated with cardiometabolic status in testicular cancer survivors. In 173 chemotherapy-treated testicular cancer survivors, hormone levels and cardiometabolic status were evaluated cross-sectionally (median 5 years [range 3-20] after chemotherapy) and correlated with SNPs in SRD5A2. The metabolic syndrome was more prevalent in survivors who were homozygous or heterozygous variant for SRD5A2 rs523349 compared to wild type (33% versus 19%, P = 0.032). In particular, patients with lower testosterone levels (testicular cancer survivors homozygous or heterozygous variant for SNP rs523349 in SRD5A2. Altered androgen sensitivity appears to be involved in the development of adverse metabolic and vascular changes in testicular cancer survivors and is a target for intervention. Copyright © 2015 Elsevier Ltd. All rights reserved.

Glucokinase gene promoter -30G>A polymorphism: a cross-sectional association study with obesity, diabetes Mellitus, hyperlipidemia, hypertension and metabolic syndrome in an Iranian hospital

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Mohammad Reza Oladi

2012-08-01

Full Text Available OBJECTIVE: A -30G>A single nucleotide polymorphism in the promoter region of the glucokinase gene has been previously associated with obesity, insulin resistance and diabetes. The present study aimed to evaluate the association of this polymorphism with obesity and its comorbidities in a population from Northeast Iran. METHODS: Five hundred and forty-two subjects aged 18 to 65 years were included in the study and divided into normal (BMI30, n=187 groups. All subjects were genotyped for the -30G>A polymorphism using the polymerase chain reaction-restriction fragment length polymorphism technique. RESULTS: The genotypes and allele frequencies of the three groups did not differ significantly (p>0.05. When the study population was categorized according to diabetes mellitus, hyperlipidemia, hypertension and metabolic syndrome status, no significant difference in -30G>A genotypes and alleles was found between the subgroups with and without these disorders (p>0.05, apart from a significantly higher frequency of the G allele in the hyperlipidemic vs. non-hyperlipidemic subgroup (pA polymorphism and high body mass index in the Iranian population.

Protective effect of bioflavonoid myricetin enhances carbohydrate metabolic enzymes and insulin signaling molecules in streptozotocin-cadmium induced diabetic nephrotoxic rats.

Science.gov (United States)

Kandasamy, Neelamegam; Ashokkumar, Natarajan

2014-09-01

Diabetic nephropathy is the kidney disease that occurs as a result of diabetes. The present study was aimed to evaluate the therapeutic potential of myricetin by assaying the activities of key enzymes of carbohydrate metabolism, insulin signaling molecules and renal function markers in streptozotocin (STZ)-cadmium (Cd) induced diabetic nephrotoxic rats. After myricetin treatment schedule, blood and tissue samples were collected to determine plasma glucose, insulin, hemoglobin, glycosylated hemoglobin and renal function markers, carbohydrate metabolic enzymes in the liver and insulin signaling molecules in the pancreas and skeletal muscle. A significant increase of plasma glucose, glycosylated hemoglobin, urea, uric acid, creatinine, blood urea nitrogen (BUN), urinary albumin, glycogen phosphorylase, glucose-6-phosphatase, and fructose-1,6-bisphosphatase and a significant decrease of plasma insulin, hemoglobin, hexokinase, glucose-6-phosphate dehydrogenase, glycogen and glycogen synthase with insulin signaling molecule expression were found in the STZ-Cd induced diabetic nephrotoxic rats. The administration of myricetin significantly normalizes the carbohydrate metabolic products like glucose, glycated hemoglobin, glycogen phosphorylase and gluconeogenic enzymes and renal function markers with increase insulin, glycogen, glycogen synthase and insulin signaling molecule expression like glucose transporter-2 (GLUT-2), glucose transporter-4 (GLUT-4), insulin receptor-1 (IRS-1), insulin receptor-2 (IRS-2) and protein kinase B (PKB). Based on the data, the protective effect of myricetin was confirmed by its histological annotation of the pancreas, liver and kidney tissues. These findings suggest that myricetin improved carbohydrate metabolism which subsequently enhances glucose utilization and renal function in STZ-Cd induced diabetic nephrotoxic rats. Copyright © 2014 Elsevier Inc. All rights reserved.

Polymorphisms in folate metabolism genes are associated with susceptibility to presbycusis.

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Manche, Santoshi Kumari; Jangala, Madhavi; Dudekula, Dinesh; Koralla, Meganadh; Akka, Jyothy

2018-03-01

Presbycusis or age related hearing loss is caused by several extrinsic and intrinsic factors that damage the auditory system. Gene polymorphisms in folate metabolism were found to play an important role in the etiology of presbycusis. The present study aimed to investigate the role of 5,10-methylenetetrahydrofolate reductase (MTHFR), methionine synthase (MTR) and thymidylate synthase (TYMS) gene polymorphisms in the onset of presbycusis in a South Indian population. A total of 220 subjects confirmed with presbycusis along with 270 age and sex matched healthy controls visiting MAA ENT Hospitals, Hyderabad, India were enrolled for the study. Genotyping of MTHFR C677T (rs180133) and A1298C (rs1801131), MTR A2756G (rs1805087), TSER (rs1801136) and TS1494indel6 bp (rs16430) was carried out using PCR & PCR-RFLP methods. The 'TT' genotype of MTHFR C677T and '152 bp/152 bp' genotype of TS1494indel6 bp showed statistically significant risk for presbycusis while CC genotype of MTHFR A1298C, '2R/2R' genotype of TSER at 3'UTR and 6 bp ins/6 bp ins of TYMS at 5'UTR were found to be protective. The T-A-A haplotype combination of MTHFR C677T, MTHFR A1298C and MTR A2756G as well as 3R- 152 bp of TYMS at 5'UTR and 3'UTR were also found to contribute significant risk for the onset of presbycusis. Further, the combination of SNP loci TSER: TS1494indel6 bp exhibited moderate linkage in presbycusis. The present pilot study identified the significant association of gene variants of MTHFR and TYMS with presbycusis. These findings aid in early diagnosis of hearing loss in the elderly population. Copyright © 2018 Elsevier Inc. All rights reserved.

Dynamics of some conjugated enzymes of aminonitrogen metabolism in the liver of the irradiated body

International Nuclear Information System (INIS)

Savitskij, V.I.

1976-01-01

Changes in the activity of five conjugated enzymes of the aminonitrogen metabolism in subcellular fractions of liver tissue have been studied on irradiated (450 R) rabbits during thirty days after exposure. These changes are peculiar for their manifestation in time, their depth and trend. It is suggested that in the early period of radiation damage, gluconeogenesis is enhanced, and in the later period, biosynthesis of pyrimidine bases is intensified

Sterol composition of yeast organelle membranes and subcellular distribution of enzymes involved in sterol metabolism.

OpenAIRE

Zinser, E; Paltauf, F; Daum, G

1993-01-01

Organelles of the yeast Saccharomyces cerevisiae were isolated and analyzed for sterol composition and the activity of three enzymes involved in sterol metabolism. The plasma membrane and secretory vesicles, the fractions with the highest sterol contents, contain ergosterol as the major sterol. In other subcellular membranes, which exhibit lower sterol contents, intermediates of the sterol biosynthetic pathway were found at higher percentages. Lipid particles contain, in addition to ergostero...

Genetic variants of methyl metabolizing enzymes and epigenetic regulators: Associations with promoter CpG island hypermethylation in colorectal cancer

NARCIS (Netherlands)

Vogel, S. de; Wouters, K.A.D.; Gottschalk, R.W.H.; Schooten, F.J. van; Goeij, A.F.P.M. de; Bruïne, A.P. de; Goldbohm, R.A.; Brandt, P.A. van den; Weijenberg, M.P.; Engeland, M. van

2009-01-01

Aberrant DNA methylation affects carcinogenesis of colorectal cancer. Folate metabolizing enzymes may influence the bioavailability of methyl groups, whereas DNA and histone methyltransferases are involved in epigenetic regulation of gene expression. We studied associations of genetic variants of

Effect of honokiol on the induction of drug-metabolizing enzymes in human hepatocytes

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Cho YY

2014-11-01

Full Text Available Yong-Yeon Cho,1 Hyeon-Uk Jeong,1 Jeong-Han Kim,2 Hye Suk Lee1 1College of Pharmacy, The Catholic University of Korea, Bucheon, Korea; 2Department of Agricultural Biotechnology, Seoul National University, Seoul, Korea Abstract: Honokiol, 2-(4-hydroxy-3-prop-2-enyl-phenyl-4-prop-2-enyl-phenol, an active component of Magnolia officinalis and Magnolia grandiflora, exerts various pharmacological activities such as antitumorigenic, antioxidative, anti-inflammatory, neurotrophic, and antithrombotic effects. To investigate whether honokiol acts as a perpetrator in drug interactions, messenger ribonucleic acid (mRNA levels of phase I and II drug-metabolizing enzymes, including cytochrome P450 (CYP, UDP-glucuronosyltransferase (UGT, and sulfotransferase 2A1 (SULT2A1, were analyzed by real-time reverse transcription polymerase chain reaction following 48-hour honokiol exposure in three independent cryopreserved human hepatocyte cultures. Honokiol treatment at the highest concentration tested (50 µM increased the CYP2B6 mRNA level and CYP2B6-catalyzed bupropion hydroxylase activity more than two-fold in three different hepatocyte cultures, indicating that honokiol induces CYP2B6 at higher concentrations. However, honokiol treatment (0.5–50 µM did not significantly alter the mRNA levels of phase I enzymes (CYP1A2, CYP3A4, CYP2C8, CYP2C9, and CYP2C19 or phase II enzymes (UGT1A1, UGT1A4, UGT1A9, UGT2B7, and SULT2A1 in cryopreserved human hepatocyte cultures. CYP1A2-catalyzed phenacetin O-deethylase and CYP3A4-catalyzed midazolam 1'-hydroxylase activities were not affected by 48-hour honokiol treatment in cryopreserved human hepatocytes. These results indicate that honokiol is a weak CYP2B6 inducer and is unlikely to increase the metabolism of concomitant CYP2B6 substrates and cause pharmacokinetic-based drug interactions in humans. Keywords: honokiol, human hepatocytes, drug interactions, cytochrome P450, UDP-glucuronosyltransferases

Interindividual Differences in Caffeine Metabolism and Factors Driving Caffeine Consumption.

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Nehlig, Astrid

2018-04-01

Most individuals adjust their caffeine intake according to the objective and subjective effects induced by the methylxanthine. However, to reach the desired effects, the quantity of caffeine consumed varies largely among individuals. It has been known for decades that the metabolism, clearance, and pharmacokinetics of caffeine is affected by many factors such as age, sex and hormones, liver disease, obesity, smoking, and diet. Caffeine also interacts with many medications. All these factors will be reviewed in the present document and discussed in light of the most recent data concerning the genetic variability affecting caffeine levels and effects at the pharmacokinetic and pharmacodynamic levels that both critically drive the level of caffeine consumption. The pharmacokinetics of caffeine are highly variable among individuals due to a polymorphism at the level of the CYP1A2 isoform of cytochrome P450, which metabolizes 95% of the caffeine ingested. Moreover there is a polymorphism at the level of another critical enzyme, N -acetyltransferase 2. At the pharmacodynamic level, there are several polymorphisms at the main brain target of caffeine, the adenosine A2A receptor or ADORA2. Genetic studies, including genome-wide association studies, identified several loci critically involved in caffeine consumption and its consequences on sleep, anxiety, and potentially in neurodegenerative and psychiatric diseases. We start reaching a better picture on how a multiplicity of biologic mechanisms seems to drive the levels of caffeine consumption, although much more knowledge is still required to understand caffeine consumption and effects on body functions. Copyright © 2018 by The American Society for Pharmacology and Experimental Therapeutics.

Assessment of mercaptopurine (6MP) metabolites and 6MP metabolic key-enzymes in childhood acute lymphoblastic leukemia.

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Wojtuszkiewicz, Anna; Barcelos, Ana; Dubbelman, Boas; De Abreu, Ronney; Brouwer, Connie; Bökkerink, Jos P; de Haas, Valerie; de Groot-Kruseman, Hester; Jansen, Gerrit; Kaspers, Gertjan L; Cloos, Jacqueline; Peters, G J

2014-01-01

Pediatric acute lymphoblastic leukemia (ALL) is treated with combination chemotherapy including mercaptopurine (6MP) as an important component. Upon its uptake, 6MP undergoes a complex metabolism involving many enzymes and active products. The prognostic value of all the factors engaged in this pathway still remains unclear. This study attempted to determine which components of 6MP metabolism in leukemic blasts and red blood cells are important for 6MP's sensitivity and toxicity. In addition, changes in the enzymatic activities and metabolite levels during the treatment were analyzed. In a cohort (N=236) of pediatric ALL patients enrolled in the Dutch ALL-9 protocol, we studied the enzymes inosine-5'-monophosphate dehydrogenase (IMPDH), thiopurine S-methyltransferase (TPMT), hypoxanthine guanine phosphoribosyl transferase (HGPRT), and purine nucleoside phosphorylase (PNP) as well as thioguanine nucleotides (TGN) and methylthioinosine nucleotides (meTINs). Activities of selected enzymes and levels of 6MP derivatives were measured at various time points during the course of therapy. The data obtained and the toxicity related parameters available for these patients were correlated with each other. We found several interesting relations, including high concentrations of two active forms of 6MP--TGN and meTIN--showing a trend toward association with better in vitro antileukemic effect of 6MP. High concentrations of TGN and elevated activity of HGPRT were found to be significantly associated with grade III/IV leucopenia. However, a lot of data of enzymatic activities and metabolite concentrations as well as clinical toxicity were missing, thereby limiting the number of assessed relations. Therefore, although a complex study of 6MP metabolism in ALL patients is feasible, it warrants more robust and strict data collection in order to be able to draw more reliable conclusions.

Investigation on the Metabolic Regulation of pgi gene knockout Escherichia coli by Enzyme Activities and Intracellular Metabolite Concentrations

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Nor ‘Aini, A. R.

2006-01-01

Full Text Available An integrated analysis of the cell growth characteristics, enzyme activities, intracellular metabolite concentrations was made to investigate the metabolic regulation of pgi gene knockout Escherichia coli based on batch culture and continuous culture which was performed at the dilution rate of 0.2h-1. The enzymatic study identified that pathways of pentose phosphate, ED pathway and glyoxylate shunt were all active in pgi mutant. The glycolysis enzymes i.e glyceraldehyde-3-phosphate dehydrogenase, fructose diphosphatase, pyruvate kinase, triose phosphate isomerase were down regulated implying that the inactivation of pgi gene reduced the carbon flux through glycolytic pathway. Meanwhile, the pentose phosphate pathway was active as a major route for intermediary carbohydrate metabolism instead of glycolysis. The pentose phosphate pathway generates most of the major reducing co-factor NADPH as shown by the increased of NADPH/NADP+ ratio in the mutant when compared with the parent strain. The fermentative enzymes such as acetate kinase and lactate dehydrogenase were down regulated in the mutant. Knockout of pgi gene results in the significant increase in the intracellular concentration of glucose-6-phosphate and decrease in the concentration of oxaloacetate. The slow growth rate of the mutant was assumed to be affected by the accumulation of glucose-6-phosphate and imbalance of NADPH reoxidation.

Targeting of ECM molecules and their metabolizing enzymes and receptors for the treatment of CNS diseases

DEFF Research Database (Denmark)

Berezin, Vladimir; Walmod, Peter Schledermann; Filippov, Mikhail

2014-01-01

Extracellular matrix (ECM) molecules, their receptors at the cell surface, and cell adhesion molecules (CAMs) involved in cell-cell or cell-ECM interactions are implicated in processes related to major diseases of the central nervous system including Alzheimer's disease (AD), epilepsy......, schizophrenia, addiction, multiple sclerosis, Parkinson's disease, and cancer. There are multiple strategies for targeting the ECM molecules and their metabolizing enzymes and receptors with antibodies, peptides, glycosaminoglycans, and other natural and synthetic compounds. ECM-targeting treatments include...... chondroitinase ABC, heparin/heparan sulfate-mimicking oligosaccharides, ECM cross-linking antibodies, and drugs stimulating expression of ECM molecules. The amount or activity of ECM-degrading enzymes like matrix metalloproteinases can be modulated indirectly via the regulation of endogenous inhibitors like...

Xenobiotic Metabolism and Gut Microbiomes.

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Anubhav Das

Full Text Available Humans are exposed to numerous xenobiotics, a majority of which are in the form of pharmaceuticals. Apart from human enzymes, recent studies have indicated the role of the gut bacterial community (microbiome in metabolizing xenobiotics. However, little is known about the contribution of the plethora of gut microbiome in xenobiotic metabolism. The present study reports the results of analyses on xenobiotic metabolizing enzymes in various human gut microbiomes. A total of 397 available gut metagenomes from individuals of varying age groups from 8 nationalities were analyzed. Based on the diversities and abundances of the xenobiotic metabolizing enzymes, various bacterial taxa were classified into three groups, namely, least versatile, intermediately versatile and highly versatile xenobiotic metabolizers. Most interestingly, specific relationships were observed between the overall drug consumption profile and the abundance and diversity of the xenobiotic metabolizing repertoire in various geographies. The obtained differential abundance patterns of xenobiotic metabolizing enzymes and bacterial genera harboring them, suggest their links to pharmacokinetic variations among individuals. Additional analyses of a few well studied classes of drug modifying enzymes (DMEs also indicate geographic as well as age specific trends.

Genetic polymorphisms of antioxidant enzymes CAT and SOD affect the outcome of clinical, biochemical, and anthropometric variables in people with obesity under a dietary intervention.

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Hernández-Guerrero, César; Parra-Carriedo, Alicia; Ruiz-de-Santiago, Diana; Galicia-Castillo, Oscar; Buenrostro-Jáuregui, Mario; Díaz-Gutiérrez, Carmen

2018-01-01

Genetic polymorphisms of antioxidant enzymes CAT, GPX, and SOD are involved in the etiology of obesity and its principal comorbidities. The aim of the present study was to analyze the effect of aforementioned SNPs over the output of several variables in people with obesity after a nutritional intervention. The study included 92 Mexican women, which received a dietary intervention by 3 months. Participants were genotyped and stratified into two groups: (1) carriers; mutated homozygous plus heterozygous (CR) and (2) homozygous wild type (WT). A comparison between CR and WT was done in clinical (CV), biochemical (BV), and anthropometric variables (AV), at the beginning and at the end of the intervention. Participants ( n  = 92) showed statistically significant differences ( p  T GPX1 (rs1050450), - 251A>G SOD1 (rs2070424), and - 262C>T CAT (rs1001179). (B) Only CR showed statistically changes ( p  T CAT (rs7943316) and 47C>T SOD2 (rs4880). The dietary intervention effect was statistically significantly between the polymorphisms of 47C>T SOD2 and BMI, SBP, TBARS, total cholesterol, and C-LCL ( p  T CAT (rs7943316) and SBP, DBP, total cholesterol, and atherogenic index ( p  CAT enzymes.

Characterization of Genes Encoding Key Enzymes Involved in Anthocyanin Metabolism of Kiwifruit during Storage Period

OpenAIRE

Li, Boqiang; Xia, Yongxiu; Wang, Yuying; Qin, Guozheng; Tian, Shiping

2017-01-01

‘Hongyang’ is a red fleshed kiwifruit with high anthocyanin content. In this study, we mainly investigated effects of different temperatures (25 and 0°C) on anthocyanin biosynthesis in harvested kiwifruit, and characterized the genes encoding key enzymes involved in anthocyanin metabolism, as well as evaluated the mode of the action, by which low temperature regulates anthocyanin accumulation in ‘Hongyang’ kiwifruit during storage period. The results showed that low temperature could effectiv...

Gene expression of transporters and phase I/II metabolic enzymes in murine small intestine during fasting

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van der Meijde Jolanda

2007-08-01

Full Text Available Abstract Background Fasting has dramatic effects on small intestinal transport function. However, little is known on expression of intestinal transport and phase I/II metabolism genes during fasting and the role the fatty acid-activated transcription factor PPARα may play herein. We therefore investigated the effects of fasting on expression of these genes using Affymetrix GeneChip MOE430A arrays and quantitative RT-PCR. Results After 24 hours of fasting, expression levels of 33 of the 253 analyzed transporter and phase I/II metabolism genes were changed. Upregulated genes were involved in transport of energy-yielding molecules in processes such as glycogenolysis (G6pt1 and mitochondrial and peroxisomal oxidation of fatty acids (Cact, Mrs3/4, Fatp2, Cyp4a10, Cyp4b1. Other induced genes were responsible for the inactivation of the neurotransmitter serotonin (Sert, Sult1d1, Dtd, Papst2, formation of eicosanoids (Cyp2j6, Cyp4a10, Cyp4b1, or for secretion of cholesterol (Abca1 and Abcg8. Cyp3a11, typically known because of its drug metabolizing capacity, was also increased. Fasting had no pronounced effect on expression of phase II metabolic enzymes, except for glutathione S-transferases which were down-regulated. Time course studies revealed that some genes were acutely regulated, whereas expression of other genes was only affected after prolonged fasting. Finally, we identified 8 genes that were PPARα-dependently upregulated upon fasting. Conclusion We have characterized the response to fasting on expression of transporters and phase I/II metabolic enzymes in murine small intestine. Differentially expressed genes are involved in a variety of processes, which functionally can be summarized as a increased oxidation of fat and xenobiotics, b increased cholesterol secretion, c increased susceptibility to electrophilic stressors, and d reduced intestinal motility. This knowledge increases our understanding of gut physiology, and may be of relevance

Study of obesity associated proopiomelanocortin gene polymorphism: Relation to metabolic profile and eating habits in a sample of obese Egyptian children and adolescents

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Farida El-Baz Mohamed

2017-01-01

Conclusion: This polymorphism was associated with higher fasting insulin levels in the obese patients only. These findings support the hypothesis that the melanocortin pathway may modulate glucose metabolism in obese subjects indicating a possible gene-environment interaction. POMC variant may be involved in the natural history of polygenic obesity, contributing to the link between type 2 diabetes and obesity.

N-acetyltransferase 2 gene polymorphism and presbycusis.

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Unal, Murat; Tamer, Lülüfer; Doğruer, Zeynep Nil; Yildirim, Hatice; Vayisoğlu, Yusuf; Camdeviren, Handan

2005-12-01

The enzyme of N-acetyltransferase (NAT) is involved in the metabolism and detoxification of cytotoxic and carcinogenic compounds as well as reactive oxygen species (ROS). The excessive amount of ROS generation occurs in the ageing inner ear. The exact etiopathogenesis of presbycusis is not known, but it is generally accepted that it is the result of series of insults, such as physiologic age-related degeneration, noise exposure, medical disorders and their treatment, as well as hereditary susceptibility. The effect of aging shows a wide interindividual range; we aimed to investigate whether profiles of NAT2 genotypes may be associated with the risk of presbycusis. Hospital-based, case-control study. We examined 68 adults with presbycusis and 98 healthy controls. DNA was extracted from whole blood, and the polymorphisms of NAT2*5A, NAT2*6A, NAT2*7A/B, and NAT2*14A were determined using a real-time polymerase chain reaction and fluorescence resonance energy transfer with a Light-Cycler Instrument. Associations between specific genotypes and the development of presbycusis were examined by use of logistic regression analyses to calculate odds ratios and 95% confidence intervals. Gene polymorphisms at NAT2*5A, NAT2*7A/B, and NAT2*14A in subjects with presbycusis were not significantly different from in the controls (P > .05). However, in NAT2*6A, the risk of presbycusis was 15.2-fold more in individuals with mutant allele than subjects with wild genotype (P = .013). Individuals with NAT2*6A heterozygote allele had a 0.34-fold less risk in the development of presbycusis than subjects with mutant allele (P = .032) We demonstrated a significant association between the NAT2*6A polymorphism and age-related hearing loss in this population. However, the sample size was relatively small, and further studies need to investigate the exact role of NAT2 gene polymorphism in the etiopathogenesis of the presbycusis.

AS3MT, GSTO, and PNP polymorphisms: impact on arsenic methylation and implications for disease susceptibility.

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Antonelli, Ray; Shao, Kan; Thomas, David J; Sams, Reeder; Cowden, John

2014-07-01

Oral exposure to inorganic arsenic (iAs) is associated with adverse health effects. Epidemiological studies suggest differences in susceptibility to these health effects, possibly due to genotypic variation. Genetic polymorphisms in iAs metabolism could lead to increased susceptibility by altering urinary iAs metabolite concentrations. To examine the impact of genotypic polymorphisms on iAs metabolism. We screened 360 publications from PubMed and Web of Science for data on urinary mono- and dimethylated arsenic (MMA and DMA) percentages and polymorphic genes encoding proteins that are hypothesized to play roles in arsenic metabolism. The genes we examined were arsenic (+3) methyltransferase (AS3MT), glutathione-s-transferase omega (GSTO), and purine nucleoside phosphorylase (PNP). Relevant data were pooled to determine which polymorphisms are associated across studies with changes in urinary metabolite concentration. In our review, AS3MT polymorphisms rs3740390, rs11191439, and rs11191453 were associated with statistically significant changes in percent urinary MMA. Studies of GSTO polymorphisms did not indicate statistically significant associations with methylation, and there are insufficient data on PNP polymorphisms to evaluate their impact on metabolism. Collectively, these data support the hypothesis that AS3MT polymorphisms alter in vivo metabolite concentrations. Preliminary evidence suggests that AS3MT genetic polymorphisms may impact disease susceptibility. GSTO polymorphisms were not associated with iAs-associated health outcomes. Additional data are needed to evaluate the association between PNP polymorphisms and iAs-associated health outcomes. Delineation of these relationships may inform iAs mode(s) of action and the approach for evaluating low-dose health effects for iAs. Genotype impacts urinary iAs metabolite concentrations and may be a potential mechanism for iAs-related disease susceptibility. Published by Elsevier Inc.

Angiotensin-converting enzyme insertion/deletion gene polymorphism in Egyptian children with systemic lupus erythematosus: a possible relation to proliferative nephritis.

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Hammad, A; Yahia, S; Laimon, W; Hamed, S M; Shouma, A; Shalaby, N M; Abdel-Hady, D; Ghanem, R; El-Farahaty, R M; El-Bassiony, S R; Hammad, E M

2017-06-01

Introduction Angiotensin-converting enzyme (ACE) is crucial in the pathogenesis of systemic lupus erythematosus through angiotensin II which regulates vascular tone and endothelial functions. Objectives To study the frequency of ACE insertion/deletion (I/D) gene polymorphism in Egyptian children with systemic lupus erythematosus and its possible relation to the renal pathology in cases with lupus nephritis. Subjects and methods The frequency of ACE gene insertion/deletion polymorphism genotypes was determined in 78 Egyptian children with systemic lupus erythematosus and compared to a matched group of 140 healthy controls using polymerase chain reaction. Results The DD genotype of the ACE gene was higher in systemic lupus erythematosus patients when compared to controls ( Plupus erythematosus patients in comparison to controls ( P lupus nephritis group, the DD genotype was significantly higher in those with proliferative lupus nephritis when compared to those with non-proliferative lupus nephritis ( P = 0.02; OR = 1.45; 95% CI = 1.4-1.6). Also, patients with proliferative lupus nephritis showed a higher frequency of the D allele ( P lupus erythematosus and occurrence of proliferative nephritis in Egyptian children.

Impact of genetic polymorphisms of SLC2A2, SLC2A5, and KHK on metabolic phenotypes in hypertensive individuals.

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MyPhuong T Le

Full Text Available In the past few decades, consumption of added sugars has increased dramatically. Studies have linked high sugar intake with increased risk for a number of diseases. Importantly, fructose, a component of sugar, has been linked with the development of features of metabolic syndrome. This study determined if single nucleotide polymorphisms in genes involved in fructose transport (solute carrier family 2 facilitated glucose transporter, member 2 (SLC2A2 and solute carrier family 2 facilitated glucose/fructose transporter, member 5 (SLC2A5 and metabolism (ketohexokinase (KHK affect inter-individual variability in metabolic phenotypes, such as increased serum uric acid levels.The influence of SLC2A2, SLC2A5, and KHK SNPs on metabolic phenotypes was tested in 237 European Americans and 167 African Americans from the Pharmacogenomic Evaluation and Antihypertensive Responses (PEAR study. Using baseline untreated fasting data, associations were considered significant if p≤0.005. These SNPs were then evaluated for potential replication (p≤0.05 using data from the Genetic Epidemiology of Responses to Antihypertensives (GERA studies.SLC2A5 rs5438 was associated with an increase in serum uric acid in European American males. However, we were unable to replicate the association in GERA. The minor allele of SLC2A2 rs8192675 showed an association with lower high-density lipoproteins in European Americans (A/A: 51.0 mg/dL, A/G: 47.0 mg/dL, G/G: 41.5 mg/dL, p = 0.0034 in PEAR. The association between rs8192675 and lower high-density lipoproteins was replicated in the combined European American GERA study samples (A/A: 47.6 mg/dL, A/G: 48.6 mg/dL, G/G: 41.9 mg/dL, p = 0.0315.The association between SLC2A2 rs8192675 and high-density lipoproteins suggests the polymorphism may play a role in influencing high-density lipoproteins and thus metabolic risk of cardiovascular disease.

Differential 3-bromopyruvate inhibition of cytosolic and mitochondrial human serine hydroxymethyltransferase isoforms, key enzymes in cancer metabolic reprogramming.

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Paiardini, Alessandro; Tramonti, Angela; Schirch, Doug; Guiducci, Giulia; di Salvo, Martino Luigi; Fiascarelli, Alessio; Giorgi, Alessandra; Maras, Bruno; Cutruzzolà, Francesca; Contestabile, Roberto

2016-11-01

The cytosolic and mitochondrial isoforms of serine hydroxymethyltransferase (SHMT1 and SHMT2, respectively) are well-recognized targets of cancer research, since their activity is critical for purine and pyrimidine biosynthesis and because of their prominent role in the metabolic reprogramming of cancer cells. Here we show that 3-bromopyruvate (3BP), a potent novel anti-tumour agent believed to function primarily by blocking energy metabolism, differentially inactivates human SHMT1 and SHMT2. SHMT1 is completely inhibited by 3BP, whereas SHMT2 retains a significant fraction of activity. Site directed mutagenesis experiments on SHMT1 demonstrate that selective inhibition relies on the presence of a cysteine residue at the active site of SHMT1 (Cys204) that is absent in SHMT2. Our results show that 3BP binds to SHMT1 active site, forming an enzyme-3BP complex, before reacting with Cys204. The physiological substrate l-serine is still able to bind at the active site of the inhibited enzyme, although catalysis does not occur. Modelling studies suggest that alkylation of Cys204 prevents a productive binding of l-serine, hampering interaction between substrate and Arg402. Conversely, the partial inactivation of SHMT2 takes place without the formation of a 3BP-enzyme complex. The introduction of a cysteine residue in the active site of SHMT2 by site directed mutagenesis (A206C mutation), at a location corresponding to that of Cys204 in SHMT1, yields an enzyme that forms a 3BP-enzyme complex and is completely inactivated. This work sets the basis for the development of selective SHMT1 inhibitors that target Cys204, starting from the structure and reactivity of 3BP. Copyright © 2016 Elsevier B.V. All rights reserved.

Apolipoprotein C3 polymorphisms, cognitive function and diabetes in Caribbean origin Hispanics.

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Caren E Smith

Full Text Available Apolipoprotein C3 (APOC3 modulates triglyceride metabolism through inhibition of lipoprotein lipase, but is itself regulated by insulin, so that APOC3 represents a potential mechanism by which glucose metabolism may affect lipid metabolism. Unfavorable lipoprotein profiles and impaired glucose metabolism are linked to cognitive decline, and all three conditions may decrease lifespan. Associations between apolipoprotein C3 (APOC3 gene polymorphisms and impaired lipid and glucose metabolism are well-established, but potential connections between APOC3 polymorphisms, cognitive decline and diabetes deserve further attention.We examined whether APOC3 single nucleotide polymorphisms (SNPs m482 (rs2854117 and 3u386 (rs5128 were related to cognitive measures, whether the associations between cognitive differences and genotype were related to metabolic differences, and how diabetes status affected these associations. Study subjects were Hispanics of Caribbean origin (n = 991, aged 45-74 living in the Boston metropolitan area.Cognitive and metabolic measures differed substantially by type II diabetes status. In multivariate regression models, APOC3 m482 AA subjects with diabetes exhibited lower executive function (P = 0.009, Stroop color naming score (P = 0.014 and Stroop color-word score (P = 0.022 compared to AG/GG subjects. APOC3 m482 AA subjects with diabetes exhibited significantly higher glucose (P = 0.032 and total cholesterol (P = 0.028 compared to AG/GG subjects. APOC3 3u386 GC/GG subjects with diabetes exhibited significantly higher triglyceride (P = 0.004, total cholesterol (P = 0.003 and glucose (P = 0.016 compared to CC subjects.In summary, we identified significant associations between APOC3 polymorphisms, impaired cognition and metabolic dysregulation in Caribbean Hispanics with diabetes. Further research investigating these relationships in other populations is warranted.

SHBG gene polymorphism (rs1799941 associates with metabolic syndrome in children and adolescents.