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Sample records for endocannabinoid metabolizing enzymes

  1. Endocannabinoids, Related Compounds and Their Metabolic Routes

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    Filomena Fezza

    2014-10-01

    Full Text Available Endocannabinoids are lipid mediators able to bind to and activate cannabinoid receptors, the primary molecular targets responsible for the pharmacological effects of the Δ9-tetrahydrocannabinol. These bioactive lipids belong mainly to two classes of compounds: N-acylethanolamines and acylesters, being N-arachidonoylethanolamine (AEA and 2-arachidonoylglycerol (2-AG, respectively, their main representatives. During the last twenty years, an ever growing number of fatty acid derivatives (endocannabinoids and endocannabinoid-like compounds have been discovered and their activities biological is the subject of intense investigations. Here, the most recent advances, from a therapeutic point of view, on endocannabinoids, related compounds, and their metabolic routes will be reviewed.

  2. The activity of the endocannabinoid metabolising enzyme fatty acid amide hydrolase in subcutaneous adipocytes correlates with BMI in metabolically healthy humans

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    Alexander Stephen PH

    2011-08-01

    Full Text Available Abstract Background The endocannabinoid system (ECS is a ubiquitously expressed signalling system, with involvement in lipid metabolism and obesity. There are reported changes in obesity of blood concentrations of the endocannabinoids anandamide (AEA and 2-arachidonoylglcyerol (2-AG, and of adipose tissue expression levels of the two key catabolic enzymes of the ECS, fatty acid amide hydrolase (FAAH and monoacylglycerol lipase (MGL. Surprisingly, however, the activities of these enzymes have not been assayed in conditions of increasing adiposity. The aim of the current study was to investigate whether FAAH and MGL activities in human subcutaneous adipocytes are affected by body mass index (BMI, or other markers of adiposity and metabolism. Methods Subcutaneous abdominal mature adipocytes, fasting blood samples and anthropometric measurements were obtained from 28 metabolically healthy subjects representing a range of BMIs. FAAH and MGL activities were assayed in mature adipocytes using radiolabelled substrates. Serum glucose, insulin and adipokines were determined using ELISAs. Results MGL activity showed no relationship with BMI or other adiposity indices, metabolic markers (fasting serum insulin or glucose or serum adipokine levels (adiponectin, leptin or resistin. In contrast, FAAH activity in subcutaneous adipocytes correlated positively with BMI and waist circumference, but not with skinfold thickness, metabolic markers or serum adipokine levels. Conclusions In this study, novel evidence is provided that FAAH activity in subcutaneous mature adipocytes increases with BMI, whereas MGL activity does not. These findings support the hypothesis that some components of the ECS are upregulated with increasing adiposity in humans, and that AEA and 2-AG may be regulated differently.

  3. Endocannabinoids

    DEFF Research Database (Denmark)

    Hansen, Harald S.; Petersen, G.; Artmann, A.

    2006-01-01

    The endocannabinoid system embraces a group of lipid molecules, enzymes and receptor proteins. This system appears to be involved in the modulation of neurotransmitter release thereby modifying learning and memory, in the regulation of food intake, and in the modulation of inflammation and pain...

  4. Metabolism of the Endocannabinoid Anandamide: Open Questions after 25 Years

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    Mauro Maccarrone

    2017-05-01

    Full Text Available Cannabis extracts have been used for centuries, but its main active principle ∆9-tetrahydrocannabinol (THC was identified about 50 years ago. Yet, it is only 25 years ago that the first endogenous ligand of the same receptors engaged by the cannabis agents was discovered. This “endocannabinoid (eCB” was identified as N-arachidonoylethanolamine (or anandamide (AEA, and was shown to have several receptors, metabolic enzymes and transporters that altogether drive its biological activity. Here I report on the latest advances about AEA metabolism, with the aim of focusing open questions still awaiting an answer for a deeper understanding of AEA activity, and for translating AEA-based drugs into novel therapeutics for human diseases.

  5. Effects of activation of endocannabinoid system on myocardial metabolism

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    Agnieszka Polak

    2016-05-01

    Full Text Available Endocannabinoids exert their effect on the regulation of energy homeostasis via activation of specific receptors. They control food intake, secretion of insulin, lipids and glucose metabolism, lipid storage. Long chain fatty acids are the main myocardial energy substrate. However, the heart exerts enormous metabolic flexibility emphasized by its ability to utilzation not only fatty acids, but also glucose, lactate and ketone bodies. Endocannabinoids can directly act on the cardiomyocytes through the CB1 and CB2 receptors present in cardiomyocytes. It appears that direct activation of CB1 receptors promotes increased lipogenesis, pericardial steatosis and bioelectrical dysfunction of the heart. In contrast, stimulation of CB2 receptors exhibits cardioprotective properties, helping to maintain appropriate amount of ATP in cardiomyocytes. Furthermore, the effects of endocannabinoids at both the central nervous system and peripheral tissues, such as liver, pancreas, or adipose tissue, resulting indirectly in plasma availability of energy substrates and affects myocardial metabolism. To date, there is little evidence that describes effects of activation of the endocannabinoid system in the cardiovascular system under physiological conditions. In the present paper the impact of metabolic diseases, i. e. obesity and diabetes, as well as the cardiovascular diseases - hypertension, myocardial ischemia and myocardial infarction on the deregulation of the endocannabinoid system and its effect on the metabolism are described.

  6. Endocannabinoid Catabolic Enzymes Play Differential Roles in Thermal Homeostasis in Response to Environmental or Immune Challenge.

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    Nass, Sara R; Long, Jonathan Z; Schlosburg, Joel E; Cravatt, Benjamin F; Lichtman, Aron H; Kinsey, Steven G

    2015-06-01

    Cannabinoid receptor agonists, such as Δ(9)-THC, the primary active constituent of Cannabis sativa, have anti-pyrogenic effects in a variety of assays. Recently, attention has turned to the endogenous cannabinoid system and how endocannabinoids, including 2-arachidonoylglycerol (2-AG) and anandamide, regulate multiple homeostatic processes, including thermoregulation. Inhibiting endocannabinoid catabolic enzymes, monoacylglycerol lipase (MAGL) or fatty acid amide hydrolase (FAAH), elevates levels of 2-AG or anandamide in vivo, respectively. The purpose of this experiment was to test the hypothesis that endocannabinoid catabolic enzymes function to maintain thermal homeostasis in response to hypothermic challenge. In separate experiments, male C57BL/6J mice were administered a MAGL or FAAH inhibitor, and then challenged with the bacterial endotoxin lipopolysaccharide (LPS; 2 mg/kg ip) or a cold (4 °C) ambient environment. Systemic LPS administration caused a significant decrease in core body temperature after 6 h, and this hypothermia persisted for at least 12 h. Similarly, cold environment induced mild hypothermia that resolved within 30 min. JZL184 exacerbated hypothermia induced by either LPS or cold challenge, both of which effects were blocked by rimonabant, but not SR144528, indicating a CB1 cannabinoid receptor mechanism of action. In contrast, the FAAH inhibitor, PF-3845, had no effect on either LPS-induced or cold-induced hypothermia. These data indicate that unlike direct acting cannabinoid receptor agonists, which elicit profound hypothermic responses on their own, neither MAGL nor FAAH inhibitors affect normal body temperature. However, these endocannabinoid catabolic enzymes play distinct roles in thermoregulation following hypothermic challenges.

  7. Fatty Acid Modulation of the Endocannabinoid System and the Effect on Food Intake and Metabolism

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    Shaan S. Naughton

    2013-01-01

    Full Text Available Endocannabinoids and their G-protein coupled receptors (GPCR are a current research focus in the area of obesity due to the system’s role in food intake and glucose and lipid metabolism. Importantly, overweight and obese individuals often have higher circulating levels of the arachidonic acid-derived endocannabinoids anandamide (AEA and 2-arachidonoyl glycerol (2-AG and an altered pattern of receptor expression. Consequently, this leads to an increase in orexigenic stimuli, changes in fatty acid synthesis, insulin sensitivity, and glucose utilisation, with preferential energy storage in adipose tissue. As endocannabinoids are products of dietary fats, modification of dietary intake may modulate their levels, with eicosapentaenoic and docosahexaenoic acid based endocannabinoids being able to displace arachidonic acid from cell membranes, reducing AEA and 2-AG production. Similarly, oleoyl ethanolamide, a product of oleic acid, induces satiety, decreases circulating fatty acid concentrations, increases the capacity for β-oxidation, and is capable of inhibiting the action of AEA and 2-AG in adipose tissue. Thus, understanding how dietary fats alter endocannabinoid system activity is a pertinent area of research due to public health messages promoting a shift towards plant-derived fats, which are rich sources of AEA and 2-AG precursor fatty acids, possibly encouraging excessive energy intake and weight gain.

  8. Inhibition of endocannabinoid metabolism by the metabolites of ibuprofen and flurbiprofen.

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    Karlsson, Jessica; Fowler, Christopher J

    2014-01-01

    In addition to their effects upon prostaglandin synthesis, the non-steroidal anti-inflammatory drugs ibuprofen and flurbiprofen inhibit the metabolism of the endocannabinoids 2-arachidonoylglycerol (2-AG) and anandamide (AEA) by cyclooxygenase-2 (COX-2) and fatty acid amide hydrolase (FAAH), respectively. Here, we investigated whether these effects upon endocannabinoid metabolism are shared by the main metabolites of ibuprofen and flurbiprofen. COX activities were measured via changes in oxygen consumption due to oxygenation of arachidonic acid (for COX-1) and arachidonic acid and 2-AG (for COX-2). FAAH activity was quantified by measuring hydrolysis of tritium labelled AEA in rat brain homogenates. The ability of ibuprofen and flurbiprofen to inhibit COX-2-catalysed oxygenation of 2-AG at lower concentrations than the oxygenation of arachidonic acid was seen with 4'-hydroxyflurbiprofen and possibly also 3'-hydroxyibuprofen, albeit at lower potencies than the parent compounds. All ibuprofen and flurbiprofen metabolites retained the ability to inhibit FAAH in a pH-dependent manner, although the potency was lower than seen with the parent compounds. It is concluded that the primary metabolites of ibuprofen and flurbiprofen retain some of the properties of the parent compound with respect to inhibition of endocannabinoid metabolism. However, these effects are unlikely to contribute to the actions of the parent compounds in vivo.

  9. Inhibition of endocannabinoid metabolism by the metabolites of ibuprofen and flurbiprofen.

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    Jessica Karlsson

    Full Text Available In addition to their effects upon prostaglandin synthesis, the non-steroidal anti-inflammatory drugs ibuprofen and flurbiprofen inhibit the metabolism of the endocannabinoids 2-arachidonoylglycerol (2-AG and anandamide (AEA by cyclooxygenase-2 (COX-2 and fatty acid amide hydrolase (FAAH, respectively. Here, we investigated whether these effects upon endocannabinoid metabolism are shared by the main metabolites of ibuprofen and flurbiprofen.COX activities were measured via changes in oxygen consumption due to oxygenation of arachidonic acid (for COX-1 and arachidonic acid and 2-AG (for COX-2. FAAH activity was quantified by measuring hydrolysis of tritium labelled AEA in rat brain homogenates. The ability of ibuprofen and flurbiprofen to inhibit COX-2-catalysed oxygenation of 2-AG at lower concentrations than the oxygenation of arachidonic acid was seen with 4'-hydroxyflurbiprofen and possibly also 3'-hydroxyibuprofen, albeit at lower potencies than the parent compounds. All ibuprofen and flurbiprofen metabolites retained the ability to inhibit FAAH in a pH-dependent manner, although the potency was lower than seen with the parent compounds.It is concluded that the primary metabolites of ibuprofen and flurbiprofen retain some of the properties of the parent compound with respect to inhibition of endocannabinoid metabolism. However, these effects are unlikely to contribute to the actions of the parent compounds in vivo.

  10. The Endocannabinoid System as a Potential Therapeutic Target for Pain Modulation

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    Ahmet Ulugöl

    2014-06-01

    Full Text Available Although cannabis has been used for pain management for millennia, very few approved cannabinoids are indicated for the treatment of pain and other medical symptoms. Cannabinoid therapy re-gained attention only after the discovery of endocannabinoids and fatty acid amide hydrolase (FAAH and monoacylglycerol lipase (MAGL, the enzymes playing a role in endocannabinoid metabolism. Nowadays, research has focused on the inhibition of these degradative enzymes and the elevation of endocannabinoid tonus locally; special emphasis is given on multi-target analgesia compounds, where one of the targets is the endocannabinoid degrading enzyme. In this review, I provide an overview of the current understanding about the processes accounting for the biosynthesis, transport and metabolism of endocannabinoids, and pharmacological approaches and potential therapeutic applications in this area, regarding the use of drugs elevating endocannabinoid levels in pain conditions.

  11. Δ9-tetrahydrocannabinol and endocannabinoid degradative enzyme inhibitors attenuate intracranial self-stimulation in mice.

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    Wiebelhaus, Jason M; Grim, Travis W; Owens, Robert A; Lazenka, Matthew F; Sim-Selley, Laura J; Abdullah, Rehab A; Niphakis, Micah J; Vann, Robert E; Cravatt, Benjamin F; Wiley, Jenny L; Negus, S Stevens; Lichtman, Aron H

    2015-02-01

    A growing body of evidence implicates endogenous cannabinoids as modulators of the mesolimbic dopamine system and motivated behavior. Paradoxically, the reinforcing effects of Δ(9)-tetrahydrocannabinol (THC), the primary psychoactive constituent of cannabis, have been difficult to detect in preclinical rodent models. In this study, we investigated the impact of THC and inhibitors of the endocannabinoid hydrolytic enzymes fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) on operant responding for electrical stimulation of the medial forebrain bundle [intracranial self-stimulation (ICSS)], which is known to activate the mesolimbic dopamine system. These drugs were also tested in assays of operant responding for food reinforcement and spontaneous locomotor activity. THC and the MAGL inhibitor JZL184 (4-[bis(1,3-benzodioxol-5-yl)hydroxymethyl]-1-piperidinecarboxylic acid 4-nitrophenyl ester) attenuated operant responding for ICSS and food, and also reduced spontaneous locomotor activity. In contrast, the FAAH inhibitor PF-3845 (N-3-pyridinyl-4-[[3-[[5-(trifluoromethyl)-2-pyridinyl]oxy]phenyl]methyl]-1-piperidinecarboxamide) was largely without effect in these assays. Consistent with previous studies showing that combined inhibition of FAAH and MAGL produces a substantially greater cannabimimetic profile than single enzyme inhibition, the dual FAAH-MAGL inhibitor SA-57 (4-[2-(4-chlorophenyl)ethyl]-1-piperidinecarboxylic acid 2-(methylamino)-2-oxoethyl ester) produced a similar magnitude of ICSS depression as that produced by THC. ICSS attenuation by JZL184 was associated with increased brain levels of 2-arachidonoylglycerol (2-AG), whereas peak effects of SA-57 were associated with increased levels of both N-arachidonoylethanolamine (anandamide) and 2-AG. The cannabinoid receptor type 1 receptor antagonist rimonabant, but not the cannabinoid receptor type 2 receptor antagonist SR144528, blocked the attenuating effects of THC, JZL184, and SA-57 on

  12. Glucose metabolism: focus on gut microbiota, the endocannabinoid system and beyond.

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    Cani, P D; Geurts, L; Matamoros, S; Plovier, H; Duparc, T

    2014-09-01

    The gut microbiota is now considered as a key factor in the regulation of numerous metabolic pathways. Growing evidence suggests that cross-talk between gut bacteria and host is achieved through specific metabolites (such as short-chain fatty acids) and molecular patterns of microbial membranes (lipopolysaccharides) that activate host cell receptors (such as toll-like receptors and G-protein-coupled receptors). The endocannabinoid (eCB) system is an important target in the context of obesity, type 2 diabetes (T2D) and inflammation. It has been demonstrated that eCB system activity is involved in the control of glucose and energy metabolism, and can be tuned up or down by specific gut microbes (for example, Akkermansia muciniphila). Numerous studies have also shown that the composition of the gut microbiota differs between obese and/or T2D individuals and those who are lean and non-diabetic. Although some shared taxa are often cited, there is still no clear consensus on the precise microbial composition that triggers metabolic disorders, and causality between specific microbes and the development of such diseases is yet to be proven in humans. Nevertheless, gastric bypass is most likely the most efficient procedure for reducing body weight and treating T2D. Interestingly, several reports have shown that the gut microbiota is profoundly affected by the procedure. It has been suggested that the consistent postoperative increase in certain bacterial groups such as Proteobacteria, Bacteroidetes and Verrucomicrobia (A. muciniphila) may explain its beneficial impact in gnotobiotic mice. Taken together, these data suggest that specific gut microbes modulate important host biological systems that contribute to the control of energy homoeostasis, glucose metabolism and inflammation in obesity and T2D. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  13. The endocannabinoid system and spermatogenesis

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    Paola eGrimaldi

    2013-12-01

    Full Text Available AbstractSpermatogenesis is a complex process in which male germ cells undergo a mitotic phase followed by meiosis and by a morphogenetic process to form mature spermatozoa. Spermatogenesis is under the control of gonadotropins, steroid hormones and it is modulated by a complex network of autocrine and paracrine factors. These modulators ensure the correct progression of germ cell differentiation to form mature spermatozoa. Recently, it has been pointed out the relevance of endocannabinoids as critical modulators of male reproduction. Endocannabinoids are natural lipids able to bind to cannabinoid receptors and whose levels are regulated by specific biosynthetic and degradative enzymes. Together with their receptors and metabolic enzymes, they form the endocannabinoid system (ECS. In male reproductive tracts, they affect Sertoli cell activities, Leydig cell proliferation, germ cell differentiation, sperm motility, capacitation and acrosome reaction. The ECS interferes with the pituitary-gonadal axis, and an intricate crosstalk between ECS and steroid hormones has been highlighted. This mini-review will focus on the involvement of the ECS in the control of spermatogenesis and on the interaction between ECS and steroid hormones.

  14. “Redundancy” of Endocannabinoid Inactivation: New Challenges and Opportunities for Pain Control

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    2012-01-01

    Redundancy of metabolic pathways and molecular targets is a typical feature of all lipid mediators, and endocannabinoids, which were originally defined as endogenous agonists at cannabinoid CB1 and CB2 receptors, are no exception. In particular, the two most studied endocannabinoids, anandamide and 2-arachidonoylglycerol, are inactivated through alternative biochemical routes, including hydrolysis and oxidation, and more than one enzyme might be used even for the same type of inactivating reaction. These enzymes also recognize as substrates other concurrent lipid mediators, whereas, in turn, endocannabinoids might interact with noncannabinoid receptors with subcellular distribution and ultimate biological actions either similar to or completely different from those of cannabinoid receptors. Even splicing variants of endocannabinoid hydrolyzing enzymes, such as FAAH-1, might play distinct roles in endocannabinoid inactivation. Finally, the products of endocannabinoid catabolism may have their own targets, with biological roles different from those of cannabinoid receptors. These peculiarities of endocannabinoid signaling have complicated the use of inhibitors of its inactivation mechanisms as a safer and more efficacious alternative to the direct targeting of cannabinoid receptors for the treatment of several pathological conditions, including pain. However, new strategies, including the rediscovery of “dirty drugs”, and the use of certain natural products (including non-THC cannabis constituents), are emerging that might allow us to make a virtue of necessity and exploit endocannabinoid redundancy to develop new analgesics. PMID:22860203

  15. Peripheral endocannabinoids regulate skeletal muscle development and maintenance

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    Dongjiao Zhao

    2010-12-01

    Full Text Available As a principal tissue responsible for insulin-mediated glucose uptake, skeletal muscle is important for whole-body health. The role of peripheral endocannabinoids as regulators of skeletal muscle metabolism has recently gained a lot of interest, as endocannabinoid system disorders could cause peripheral insulin resistance. We investigated the role of the peripheral endocannabinoid system in skeletal muscle development and maintenance. Cultures of C2C12 cells, primary satellite cells and mouse skeletal muscle single fibers were used as model systems for our studies. We found an increase in cannabinoid receptor type 1 (CB1 mRNA and endocannabinoid synthetic enzyme mRNA skeletal muscle cells during differentiation. We also found that activation of CB1 inhibited myoblast differentiation, expanded the number of satellite cells, and stimulated the fast-muscle oxidative phenotype. Our findings contribute to understanding of the role of the endocannabinoid system in skeletal muscle metabolism and muscle oxygen consumption, and also help to explain the effects of the peripheral endocannabinoid system on whole-body energy balance.

  16. Effects of a Weight Loss Program on Metabolic Syndrome, Eating Disorders and Psychological Outcomes: Mediation by Endocannabinoids.

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    Pataky, Zoltan; Carrard, Isabelle; Gay, Valerie; Thomas, Aurélien; Carpentier, Anne; Bobbioni-Harsch, Elisabetta; Golay, Alain

    2018-04-10

    To evaluate the effects of weight loss on endocannabinoids, cardiometabolic and psychological parameters, eating disorders (ED) as well as quality of life (QoL) and to elucidate the role of endocannabinoids in metabolic syndrome (MS). In total, 114 patients with obesity were prospectively included in a 12-month weight loss program. Plasma endocannabinoids were measured by mass spectrometry; ED, psychological and QoL-related parameters were evaluated by self-reported questionnaires; physical activity was measured by accelerometer. Nutritional assessment was done by a 3-day food diary. Among completers (n = 87), body weight decreased in 35 patients (-9.1 ± 8.6 kg), remained stable in 39 patients, and increased in 13 patients (+5.8 ± 3.4 kg). 75% of patients with MS at baseline were free of MS at follow-up, and their baseline plasma N-palmitoylethanolamide (PEA) values were significantly lower when compared to patients with persisting MS. At baseline, there was a positive relationship between PEA and waist circumference (p = 0.005, R2 = 0.08), fasting glucose (p < 0.0001, R2 = 0.12), total cholesterol (p = 0.001, R2 = 0.11), triglycerides (p = 0.001, R2 = 0.11), LDL-cholesterol (p = 0.03, R2 = 0.05) as well as depression score (p = 0.002, R2 = 0.29). Plasma PEA might play a role in metabolic improvement after weight loss. Even in subjects without weight loss, a multidisciplinary intervention improves psychological outcomes, ED, and QoL. © 2018 The Author(s) Published by S. Karger GmbH, Freiburg.

  17. Effects of a Weight Loss Program on Metabolic Syndrome, Eating Disorders and Psychological Outcomes: Mediation by Endocannabinoids?

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    Zoltan Pataky

    2018-04-01

    Full Text Available Objective: To evaluate the effects of weight loss on endocannabinoids, cardiometabolic and psychological parameters, eating disorders (ED as well as quality of life (QoL and to elucidate the role of endocannabinoids in metabolic syndrome (MS. Methods: In total, 114 patients with obesity were prospectively included in a 12-month weight loss program. Plasma endocannabinoids were measured by mass spectrometry; ED, psychological and QoL-related parameters were evaluated by self-reported questionnaires; physical activity was measured by accelerometer. Nutritional assessment was done by a 3-day food diary. Results: Among completers (n = 87, body weight decreased in 35 patients (-9.1 ± 8.6 kg, remained stable in 39 patients, and increased in 13 patients (+5.8 ± 3.4 kg. 75% of patients with MS at baseline were free of MS at follow-up, and their baseline plasma N-palmitoylethanolamide (PEA values were significantly lower when compared to patients with persisting MS. At baseline, there was a positive relationship between PEA and waist circumference (p = 0.005, R2 = 0.08, fasting glucose (p 2 = 0.12, total cholesterol (p = 0.001, R2 = 0.11, triglycerides (p = 0.001, R2 = 0.11, LDL-cholesterol (p = 0.03, R2 = 0.05 as well as depression score (p = 0.002, R2 = 0.29. Conclusion: Plasma PEA might play a role in metabolic improvement after weight loss. Even in subjects without weight loss, a multidisciplinary intervention improves psychological outcomes, ED, and QoL.

  18. The Endocannabinoid System: A Dynamic Signalling System at the Crossroads Between Metabolism and Disease

    NARCIS (Netherlands)

    Witkamp, R.F.

    2014-01-01

    The discovery of the endocannabinoid system (ECS) in the early 1990s of last century generated high expectations of new therapeutic opportunities. Its central role and pleiotropic character seemed to offer promising indications in the fields of pain, inflammation, CNS disorders, weight management

  19. Discriminative Stimulus Properties of the Endocannabinoid Catabolic Enzyme Inhibitor SA-57 in Mice

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    Owens, Robert A.; Ignatowska-Jankowska, Bogna; Mustafa, Mohammed; Beardsley, Patrick M.; Wiley, Jenny L.; Jali, Abdulmajeed; Selley, Dana E.; Niphakis, Micah J.; Cravatt, Benjamin F.; Lichtman, Aron H.

    2016-01-01

    Whereas the inhibition of fatty acid amide hydrolase (FAAH) or monoacylglycerol lipase (MAGL), the respective major hydrolytic enzymes of N-arachidonoyl ethanolamine (AEA) and 2-arachidonoylglycerol (2-AG), elicits no or partial substitution for Δ9-tetrahydrocannabinol (THC) in drug-discrimination procedures, combined inhibition of both enzymes fully substitutes for THC, as well as produces a constellation of cannabimimetic effects. The present study tested whether C57BL/6J mice would learn t...

  20. Monoglyceride lipase as a drug target: At the crossroads of arachidonic acid metabolism and endocannabinoid signaling.

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    Grabner, Gernot F; Zimmermann, Robert; Schicho, Rudolf; Taschler, Ulrike

    2017-07-01

    Monoglyerides (MGs) are short-lived, intermediary lipids deriving from the degradation of phospho- and neutral lipids, and monoglyceride lipase (MGL), also designated as monoacylglycerol lipase (MAGL), is the major enzyme catalyzing the hydrolysis of MGs into glycerol and fatty acids. This distinct function enables MGL to regulate a number of physiological and pathophysiological processes since both MGs and fatty acids can act as signaling lipids or precursors thereof. The most prominent MG species acting as signaling lipid is 2-arachidonoyl glycerol (2-AG) which is the most abundant endogenous agonist of cannabinoid receptors in the body. Importantly, recent observations demonstrate that 2-AG represents a quantitatively important source for arachidonic acid, the precursor of prostaglandins and other inflammatory mediators. Accordingly, MGL-mediated 2-AG degradation affects lipid signaling by cannabinoid receptor-dependent and independent mechanisms. Recent genetic and pharmacological studies gave important insights into MGL's role in (patho-)physiological processes, and the enzyme is now considered as a promising drug target for a number of disorders including cancer, neurodegenerative and inflammatory diseases. This review summarizes the basics of MG (2-AG) metabolism and provides an overview on the therapeutic potential of MGL. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. 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.

  2. 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...

  3. 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.

  4. Enzymes and Inhibitors in Neonicotinoid Insecticide Metabolism

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    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

  5. The Endocannabinoid System Affects Myocardial Glucose Metabolism in the DOCA-Salt Model of Hypertension

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    Agnieszka Polak

    2018-03-01

    Full Text Available Background/Aims: Recent interest in the use of cannabinoids as therapeutic agents has revealed the involvement of the endogenous cannabinoid system (ECS in the regulation of the cardiovascular system in hypertension. Abnormalities in glucose metabolism and insulin action are commonly detected in hypertensive animals. Thus, potential antihypertensive drugs should be investigated with respect to modulation of glucose homeostasis. Therefore, the aim of the present study was to evaluate the effects of the ECS activation after chronic fatty acid amide hydrolase inhibitor (URB597 administration on plasma glucose and insulin concentrations as well as parameters of myocardial glucose metabolism in the deoxycorticosterone acetate (DOCA-salt hypertensive rats, an animal model of secondary hypertension. Methods: Hypertension was induced by DOCA (25mg/kg injections and addition of 1% NaCl in the drinking water for six weeks. Chronic activation of the ECS was performed by URB597 (1mg/kg injections for two weeks. We examined fasting plasma levels of insulin (ELISA, glucose and intramyocardial glycogen (colorimetric method. Expressions of glucose transporters (GLUT1, 4 and selected proteins engaged in GLUT translocation as well as glucose metabolism were determined using Western blotting. Results: Hypertension induced hypoinsulinemia with concomitant lack of significant changes in glycemia, reduced intramyocardial glycogen content and increased pyruvate dehydrogenase (PDH expression in the cardiac muscle. Importantly, chronic URB597 administration in the hypertensive rats increased insulin concentration, elevated plasmalemmal GLUT1 and GLUT4 expression and concomitantly improved myocardial glycogen storage. Conclusion: Chronic administration of fatty acid amide hydrolase (FAAH inhibitor has potential protective properties on myocardial glucose metabolism in hypertension.

  6. Expression of Enzymes that Metabolize Medications

    Science.gov (United States)

    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

  7. 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.

  8. Brain uptake and metabolism of the endocannabinoid anandamide labeled in either the arachidonoyl or ethanolamine moiety

    International Nuclear Information System (INIS)

    Hu, Kun; Sonti, Shilpa; Glaser, Sherrye T.; Duclos, Richard I.; Gatley, Samuel J.

    2017-01-01

    Introduction: Anandamide (N-arachidonoylethanolamine) is a retrograde neuromodulator that activates cannabinoid receptors. The concentration of anandamide in the brain is controlled by fatty acid amide hydrolase (FAAH), which has been the focus of recent drug discovery efforts. Previous studies in C57BL/6 mice using [ 3 H-arachidonoyl]anandamide demonstrated deposition of tritium in thalamus and cortical areas that was blocked by treatment with an FAAH inhibitor and that was not seen in FAAH-knockout mice. This suggested that long chain fatty acid amides radiolabeled in the fatty acid moiety might be useful as ex vivo and in vivo radiotracers for FAAH, since labeled fatty acid released by hydrolysis would be rapidly incorporated into phospholipids with long metabolic turnover periods. Methods: Radiotracers were administered intravenously to conscious Swiss–Webster mice, and radioactivity concentrations in brain areas was quantified and radiolabeled metabolites determined by radiochromatography. Results: [ 14 C]Arachidonic acid, [ 14 C-arachidonoyl]anandamide and [ 14 C-ethanolamine]anandamide, and also [ 14 C]myristic acid, [ 14 C-myristoyl]myristoylethanolamine and [ 14 C-ethanolamine]myristoyl-ethanolamine all had very similar distribution patterns, with whole brain radioactivity concentrations of 2–4% injected dose per gram. Pretreatment with the potent selective FAAH inhibitor URB597 did not significantly alter distribution patterns although radiochromatography demonstrated that the rate of incorporation of label from [ 14 C]anandamide into phospholipids was decreased. Pretreatment with the muscarinic agonist arecoline which increases cerebral perfusion increased brain uptake of radiolabel from [ 14 C]arachidonic acid and [ 14 C-ethanolamine]anandamide, and (in dual isotope studies) from the unrelated tracer [ 125 I]RTI-55. Conclusions: Together with our previously published study with [ 18 F-palmitoyl]16-fluoro-palmitoylethanolamine, the data show that the

  9. Potential of Endocannabinoids to Control Bladder Pain

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    Dale E. Bjorling

    2018-05-01

    Full Text Available Bladder-related pain is one of the most common forms of visceral pain, and visceral pain is among the most common complaints for which patients seek physician consultation. Despite extensive studies of visceral innervation and treatment of visceral pain, opioids remain a mainstay for management of bladder pain. Side effects associated with opioid therapy can profoundly diminish quality of life, and improved options for treatment of bladder pain remain a high priority. Endocannabinoids, primarily anandamide (AEA and 2-arachidonoylglycerol (2-AG, are endogenously-produced fatty acid ethanolamides with that induce analgesia. Animal experiments have demonstrated that inhibition of enzymes that degrade AEA or 2-AG have the potential to prevent development of visceral and somatic pain. Although experimental results in animal models have been promising, clinical application of this approach has proven difficult. In addition to fatty acid amide hydrolase (FAAH; degrades AEA and monacylglycerol lipase (MAGL; degrades 2-AG, cyclooxygenase (COX acts to metabolize endocannabinoids. Another potential limitation of this strategy is that AEA activates pro-nociceptive transient receptor potential vanilloid 1 (TRPV1 channels. Dual inhibitors of FAAH and TRPV1 or FAAH and COX have been synthesized and are currently undergoing preclinical testing for efficacy in providing analgesia. Local inhibition of FAAH or MAGL within the bladder may be viable options to reduce pain associated with cystitis with fewer systemic side effects, but this has not been explored. Further investigation is required before manipulation of the endocannabinoid system can be proven as an efficacious alternative for management of bladder pain.

  10. Expression and Function of the Endocannabinoid System in the Retina and the Visual Brain

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    Jean-François Bouchard

    2016-01-01

    Full Text Available Endocannabinoids are important retrograde modulators of synaptic transmission throughout the nervous system. Cannabinoid receptors are seven transmembrane G-protein coupled receptors favoring Gi/o protein. They are known to play an important role in various processes, including metabolic regulation, craving, pain, anxiety, and immune function. In the last decade, there has been a growing interest for endocannabinoids in the retina and their role in visual processing. The purpose of this review is to characterize the expression and physiological functions of the endocannabinoid system in the visual system, from the retina to the primary visual cortex, with a main interest regarding the retina, which is the best-described area in this system so far. It will show that the endocannabinoid system is widely present in the retina, mostly in the through pathway where it can modulate neurotransmitter release and ion channel activity, although some evidence also indicates possible mechanisms via amacrine, horizontal, and Müller cells. The presence of multiple endocannabinoid ligands, synthesizing and catabolizing enzymes, and receptors highlights various pharmacological targets for novel therapeutic application to retinal diseases.

  11. Cocaine-induced behavioral sensitization decreases the expression of endocannabinoid signaling-related proteins in the mouse hippocampus.

    Science.gov (United States)

    Blanco, Eduardo; Galeano, Pablo; Palomino, Ana; Pavón, Francisco J; Rivera, Patricia; Serrano, Antonia; Alen, Francisco; Rubio, Leticia; Vargas, Antonio; Castilla-Ortega, Estela; Decara, Juan; Bilbao, Ainhoa; de Fonseca, Fernando Rodríguez; Suárez, Juan

    2016-03-01

    In the reward mesocorticolimbic circuits, the glutamatergic and endocannabinoid systems are implicated in neurobiological mechanisms underlying cocaine addiction. However, the involvement of both systems in the hippocampus, a critical region to process relational information relevant for encoding drug-associated memories, in cocaine-related behaviors remains unknown. In the present work, we studied whether the hippocampal gene/protein expression of relevant glutamate signaling components, including glutamate-synthesizing enzymes and metabotropic and ionotropic receptors, and the hippocampal gene/protein expression of cannabinoid type 1 (CB1) receptor and endocannabinoid metabolic enzymes were altered following acute and/or repeated cocaine administration resulting in conditioned locomotion and locomotor sensitization. Results showed that acute cocaine administration induced an overall down-regulation of glutamate-related gene expression and, specifically, a low phosphorylation level of GluA1. In contrast, locomotor sensitization to cocaine produced an up-regulation of several glutamate receptor-related genes and, specifically, an increased protein expression of the GluN1 receptor subunit. Regarding the endocannabinoid system, acute and repeated cocaine administration were associated with an increased gene/protein expression of CB1 receptors and a decreased gene/protein expression of the endocannabinoid-synthesis enzymes N-acyl phosphatidylethanolamine D (NAPE-PLD) and diacylglycerol lipase alpha (DAGLα). These changes resulted in an overall decrease in endocannabinoid synthesis/degradation ratios, especially NAPE-PLD/fatty acid amide hydrolase and DAGLα/monoacylglycerol lipase, suggesting a reduced endocannabinoid production associated with a compensatory up-regulation of CB1 receptor. Overall, these findings suggest that repeated cocaine administration resulting in locomotor sensitization induces a down-regulation of the endocannabinoid signaling that could

  12. 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.

  13. 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.

  14. Classical endocannabinoid-like compounds and their regulation by nutrients

    DEFF Research Database (Denmark)

    Kleberg, Karen; Hassing, Helle A.; Hansen, Harald S.

    2014-01-01

    Endocannabinoid-like compounds are structurally related to the true endocannabinoids but do not contain highly unsaturated fatty acids, and they do not bind the cannabinoid receptors. The classical endocannabinoid-like compounds include N-acylethanolamines and 2-monoacylglycerols......, which are particularly interesting in a nutritional and metabolic context. Exogenously supplied oleoylethanolamide, palmitoylethanolamide, and linoleoylethanolamide have anorexic effects, and the endogenous formation of these N-acylethanolamines in the small intestine may serve an important role...

  15. Enzyme clustering accelerates processing of intermediates through metabolic channeling

    Science.gov (United States)

    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

  16. 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 ...

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

    Science.gov (United States)

    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.

  18. The Endocannabinoid System and Sex Steroid Hormone-Dependent Cancers

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    Thangesweran Ayakannu

    2013-01-01

    Full Text Available The “endocannabinoid system (ECS” comprises the endocannabinoids, the enzymes that regulate their synthesis and degradation, the prototypical cannabinoid receptors (CB1 and CB2, some noncannabinoid receptors, and an, as yet, uncharacterised transport system. Recent evidence suggests that both cannabinoid receptors are present in sex steroid hormone-dependent cancer tissues and potentially play an important role in those malignancies. Sex steroid hormones regulate the endocannabinoid system and the endocannabinoids prevent tumour development through putative protective mechanisms that prevent cell growth and migration, suggesting an important role for endocannabinoids in the regulation of sex hormone-dependent tumours and metastasis. Here, the role of the endocannabinoid system in sex steroid hormone-dependent cancers is described and the potential for novel therapies assessed.

  19. 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

  20. Developmental programming of somatic growth, behavior and endocannabinoid metabolism by variation of early postnatal nutrition in a cross-fostering mouse model.

    Science.gov (United States)

    Schreiner, Felix; Ackermann, Merle; Michalik, Michael; Hucklenbruch-Rother, Eva; Bilkei-Gorzo, Andras; Racz, Ildiko; Bindila, Laura; Lutz, Beat; Dötsch, Jörg; Zimmer, Andreas; Woelfle, Joachim

    2017-01-01

    Nutrient deprivation during early development has been associated with the predisposition to metabolic disorders in adulthood. Considering its interaction with metabolism, appetite and behavior, the endocannabinoid (eCB) system represents a promising target of developmental programming. By cross-fostering and variation of litter size, early postnatal nutrition of CB6F1-hybrid mice was controlled during the lactation period (3, 6, or 10 pups/mother). After weaning and redistribution at P21, all pups received standard chow ad libitum. Gene expression analyses (liver, visceral fat, hypothalamus) were performed at P50, eCB concentrations were determined in liver and visceral fat. Locomotor activity and social behavior were analyzed by means of computer-assisted videotracking. Body growth was permanently altered, with differences for length, weight, body mass index and fat mass persisting beyond P100 (all 3>6>10,p6>10 (DAGLα p6>10 (FAAH pOpen-field social behavior testing revealed significant group differences, with formerly underfed mice turning out to be the most sociable animals (p<0.01). Locomotor activity did not differ. Our data indicate a developmental plasticity of somatic growth, behavior and parameters of the eCB system, with long-lasting impact of early postnatal nutrition. Developmental programming of the eCB system in metabolically active tissues, as shown here for liver and fat, may play a role in the formation of the adult cardiometabolic risk profile following perinatal malnutrition in humans.

  1. Dynamic changes to the endocannabinoid system in models of chronic pain

    Science.gov (United States)

    Rani Sagar, Devi; Burston, James J.; Woodhams, Stephen G.; Chapman, Victoria

    2012-01-01

    The analgesic effects of cannabinoid ligands, mediated by CB1 receptors are well established. However, the side-effect profile of CB1 receptor ligands has necessitated the search for alternative cannabinoid-based approaches to analgesia. Herein, we review the current literature describing the impact of chronic pain states on the key components of the endocannabinoid receptor system, in terms of regionally restricted changes in receptor expression and levels of key metabolic enzymes that influence the local levels of the endocannabinoids. The evidence that spinal CB2 receptors have a novel role in the modulation of nociceptive processing in models of neuropathic pain, as well as in models of cancer pain and arthritis is discussed. Recent advances in our understanding of the spinal location of the key enzymes that regulate the levels of the endocannabinoid 2-AG are discussed alongside the outcomes of recent studies of the effects of inhibiting the catabolism of 2-AG in models of pain. The complexities of the enzymes capable of metabolizing both anandamide (AEA) and 2-AG have become increasingly apparent. More recently, it has come to light that some of the metabolites of AEA and 2-AG generated by cyclooxygenase-2, lipoxygenases and cytochrome P450 are biologically active and can either exacerbate or inhibit nociceptive signalling. PMID:23108548

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  4. Engineering of metabolic pathways by artificial enzyme channels

    Directory of Open Access Journals (Sweden)

    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.

  5. [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.

  6. Flavonoids as modulators of metabolic enzymes and drug transporters.

    Science.gov (United States)

    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.

  7. 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.

  8. Human Metabolic Enzymes Deficiency: A Genetic Mutation Based Approach

    Directory of Open Access Journals (Sweden)

    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.

  9. 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.

  10. Prolyl hydroxylase domain enzymes: important regulators of cancer metabolism

    Directory of Open Access Journals (Sweden)

    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

  11. Increased Contextual Fear Conditioning in iNOS Knockout Mice: Additional Evidence for the Involvement of Nitric Oxide in Stress-Related Disorders and Contribution of the Endocannabinoid System

    Science.gov (United States)

    Gomes, Felipe V.; Silva, Andréia L.; Uliana, Daniela L.; Camargo, Laura H. A.; Guimarães, Francisco S.; Cunha, Fernando Q.; Joca, Sâmia R. L.; Resstel, Leonardo B. M.

    2015-01-01

    Background: Inducible or neuronal nitric oxide synthase gene deletion increases or decreases anxiety-like behavior in mice, respectively. Since nitric oxide and endocannabinoids interact to modulate defensive behavior, the former effect could involve a compensatory increase in basal brain nitric oxide synthase activity and/or changes in the endocannabinoid system. Thus, we investigated the expression and extinction of contextual fear conditioning of inducible nitric oxide knockout mice and possible involvement of endocannabinoids in these responses. Methods: We evaluated the effects of a preferential neuronal nitric oxide synthase inhibitor, 7-nitroindazol, nitric oxide synthase activity, and mRNA changes of nitrergic and endocannabinoid systems components in the medial prefrontal cortex and hippocampus of wild-type and knockout mice. The effects of URB597, an inhibitor of the fatty acid amide hydrolase enzyme, which metabolizes the endocannabinoid anandamide, WIN55,212-2, a nonselective cannabinoid agonist, and AM281, a selective CB1 antagonist, on contextual fear conditioning were also evaluated. Results: Contextual fear conditioning expression was similar in wild-type and knockout mice, but the latter presented extinction deficits and increased basal nitric oxide synthase activity in the medial prefrontal cortex. 7-Nitroindazol decreased fear expression and facilitated extinction in wild-type and knockout mice. URB597 decreased fear expression in wild-type and facilitated extinction in knockout mice, whereas WIN55,212-2 and AM281 increased it in wild-type mice. Nonconditioned knockout mice showed changes in the mRNA expression of nitrergic and endocannabinoid system components in the medial prefrontal cortex and hippocampus that were modified by fear conditioning. Conclusion: These data reinforce the involvement of the nitric oxide and endocannabinoids (anandamide) in stress-related disorders and point to a deregulation of the endocannabinoid system in

  12. In vivo enzyme activity in inborn errors of metabolism

    Energy Technology Data Exchange (ETDEWEB)

    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.

  13. 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

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

    Science.gov (United States)

    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.

  15. 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...

  16. Tools and strategies for discovering novel enzymes and metabolic pathways

    Directory of Open Access Journals (Sweden)

    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.

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

    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 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

  18. Endocannabinoids modulate apoptosis in endometriosis and adenomyosis.

    Science.gov (United States)

    Bilgic, Elif; Guzel, Elif; Kose, Sevil; Aydin, Makbule Cisel; Karaismailoglu, Eda; Akar, Irem; Usubutun, Alp; Korkusuz, Petek

    2017-06-01

    Adenomyosis that is a form of endometriosis is the growth of ectopic endometrial tissue within the muscular wall of the uterus (myometrium), which may cause dysmenorrhea and infertility. Endocannabinoid mediated apoptotic mechanisms of endometriosis and adenomyosis are not known. We hypothesized that the down regulation of endocannabinoid receptors and/or alteration in their regulatory enzymes may have a direct role in the pathogenesis of endometriosis and adenomyosis through apoptosis. Endocannabinoid receptors CB1 and CB2, their synthesizing and catabolizing enzymes (FAAH, NAPE-PLD, DAGL, MAGL) and the apoptotic indexes were immunohistochemically assessed in endometriotic and adenomyotic tissues. Findings were compared to normal endometrium and myometrium. Endometrial adenocarcinoma (Ishikawa) and ovarian endometriosis cyst wall stromal (CRL-7566) cell lines were furthermore cultured with or without cannabinoid receptor agonists. The IC50 value for CB1 and CB2 receptor agonists was quantified. Cannabinoid agonists on cell death were investigated by Annexin-V/Propidium iodide labeling with flow cytometry. CB1 and CB2 receptor levels decreased in endometriotic and adenomyotic tissues compared to the control group (p=0,001 and p=0,001). FAAH, NAPE-PLD, MAGL and DAGL enzyme levels decreased in endometriotic and adenomyotic tissues compared to control (p=0,001, p=0,001, p=0,001 and p=0,002 respectively). Apoptotic cell indexes both in endometriotic and adenomyotic tissues also decreased significantly, compared to the control group (p=0,001 and p=0,001). CB1 and CB2 receptor agonist mediated dose dependent fast anti-proliferative and pro-apoptotic effects were detected in Ishikawa and ovarian endometriosis cyst wall stromal cell lines (CRL-7566). Endocannabinoids are suggested to increase apoptosis mechanisms in endometriosis and adenomyosis. CB1 and CB2 antagonists can be considered as potential medical therapeutic agents for endometriosis and adenomyosis. Copyright

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

    Science.gov (United States)

    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.

  20. Adaptation of red cell enzymes and intermediates in metabolic disorders.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  3. The Endocannabinoid Anandamide : Metabolism & Neuroprotection

    NARCIS (Netherlands)

    Stelt, Marcelis van der

    2002-01-01

    Marijuana is an extract of the Cannabis sativa and is the most used illegal drug in the world. Public debate centres upon the possible legalization of marijuana for recreational and therapeutic uses. DELTA-exp.9-Tetrahydrocannabinol (THC), the main psychoactive compound in marijuana, exerts its

  4. 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

  5. Endocannabinoids as Guardians of Metastasis

    Directory of Open Access Journals (Sweden)

    Irmgard Tegeder

    2016-02-01

    Full Text Available Endocannabinoids including anandamide and 2-arachidonoylglycerol are involved in cancer pathophysiology in several ways, including tumor growth and progression, peritumoral inflammation, nausea and cancer pain. Recently we showed that the endocannabinoid profiles are deranged during cancer to an extent that this manifests in alterations of plasma endocannabinoids in cancer patients, which was mimicked by similar changes in rodent models of local and metastatic cancer. The present topical review summarizes the complexity of endocannabinoid signaling in the context of tumor growth and metastasis.

  6. Key Metabolic Enzymes Underlying Astrocytic Upregulation of GABAergic Plasticity

    Directory of Open Access Journals (Sweden)

    Przemysław T. Kaczor

    2017-05-01

    Full Text Available GABAergic plasticity is recognized as a key mechanism of shaping the activity of the neuronal networks. However, its description is challenging because of numerous neuron-specific mechanisms. In particular, while essential role of glial cells in the excitatory plasticity is well established, their involvement in GABAergic plasticity only starts to emerge. To address this problem, we used two models: neuronal cell culture (NC and astrocyte-neuronal co-culture (ANCC, where we chemically induced long-term potentiation at inhibitory synapses (iLTP. iLTP could be induced both in NC and ANCC but in ANCC its extent was larger. Importantly, this functional iLTP manifestation was accompanied by an increase in gephyrin puncta size. Furthermore, blocking astrocyte Krebs cycle with fluoroacetate (FA in ANCC prevented enhancement of both mIPSC amplitude and gephyrin puncta size but this effect was not observed in NC, indicating a key role in neuron-astrocyte cross-talk. Blockade of monocarboxylate transport with α-Cyano-4-hydroxycinnamic acid (4CIN abolished iLTP both in NC and ANCC and in the latter model prevented also enlargement of gephyrin puncta. Similarly, blockade of glycogen phosphorylase with BAYU6751 prevented enlargement of gephyrin puncta upon iLTP induction. Finally, block of glutamine synthetase with methionine sulfoxide (MSO nearly abolished mIPSC increase in both NMDA stimulated cell groups but did not prevent enlargement of gephyrin puncta. In conclusion, we provide further evidence that GABAergic plasticity is strongly regulated by astrocytes and the underlying mechanisms involve key metabolic enzymes. Considering the strategic role of GABAergic interneurons, the plasticity described here indicates possible mechanism whereby metabolism regulates the network activity.

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

    Science.gov (United States)

    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.

  8. Breast cancer and steroid metabolizing enzymes: the role of progestogens.

    Science.gov (United States)

    Pasqualini, Jorge R

    2009-12-01

    It is well documented that breast tissue, both normal and cancerous, contains all the enzymatic systems necessary for the bioformation and metabolic transformation of estrogens, androgens and progesterone. These include sulfatases, aromatase, hydroxysteroid-dehydrogenases, sulfotransferases, hydroxylases and glucuronidases. The control of these enzymes plays an important role in the development and pathogenesis of hormone-dependent breast cancer. As discussed in this review, various progestogens including dydrogesterone and its 20alpha-dihydro-derivative, medrogestone, promegestone, nomegestrol acetate and norelgestromin can reduce intratissular levels of estradiol in breast cancer by blocking sulfatase and 17beta-hydroxysteroid-dehydrogenase type 1 activities. A possible correlation has been postulated between breast cell proliferation and estrogen sulfotransferase activity. Progesterone is largely transformed in the breast; normal breast produces mainly 4-ene derivatives, whereas 5alpha-derivatives are most common in breast cancer tissue. It has been suggested that this specific conversion of progesterone may be involved in breast carcinogenesis. In conclusion, treatment with anti-aromatases combined with anti-sulfatase or 17beta-hydroxysteroid-dehydrogenase type 1 could provide new therapeutic possibilities in the treatment of patients with hormone-dependent breast cancer. Copyright 2009 Elsevier Ireland Ltd. All rights reserved.

  9. Endocannabinoid system in cardiovascular disorders - new pharmacotherapeutic opportunities

    Directory of Open Access Journals (Sweden)

    Pedro Cunha

    2011-01-01

    Full Text Available The long history of Cannabis sativa had its development stimulated and oriented for medicine after the discovery and chemical characterization of its main active ingredient, the 9-tetrahydrocannabinol (9-THC. Consequently, a binding site for 9-THC was identified in rat brains and the first cannabinoid receptor (CB1 was cloned, followed by the CB2 and by the discover of two endogenous agonists: anandamide and 2-arachidonoyl glycerol. Cannabinoid receptors, endocannabinoids and the enzymes that catalyze its synthesis and degradation constitute the endocannabinoid system (ECS, which plays an important role in the cardiovascular system. In vivo experiments with rats have demonstrated the action of anandamide and 2-AG on the development of atherosclerotic plaque, as well as an effect on heart rate, blood pressure, vasoactivity and energy metabolism (action in dyslipidemia and obesity. Recent studies with an antagonist of CB1 receptors showed that the modulation of ECS can play an important role in reducing cardiovascular risk in obese and dyslipidemic patients. Similarly, studies in rats have demonstrated the action of CB2 receptors in adhesion, migration, proliferation and function of immune cells involved in the atherosclerotic plaque formation process. The evidence so far gathered shows that the modulation of ECS (as agonism or antagonism of its receptors is an enormous potential field for research and intervention in multiple areas of human pathophysiology. The development of selective drugs for the CB1 and CB2 receptors may open a door to new therapeutic regimens.This review article aims to address the key findings and evidences on the modulation of ECS, in order to prospect future forms of therapeutic intervention at the cardiovascular level. A recent, emerging, controversial and of undoubted scientific interest subject, which states as a potential therapeutic target to reach in the 21 st century.

  10. 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...

  11. 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.

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

    Science.gov (United States)

    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

  13. 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

  14. Drug metabolizing enzyme systems and their relationship to toxic mechanisms

    International Nuclear Information System (INIS)

    Boyd, M.R.; Ravindranath, V.; Burka, L.T.

    1983-01-01

    The metabolism and toxicity of 3-methylfuran (3-MF) are described. The major product of metabolic activation of 3-MF appears to be disemicarbazones. Cursory description of toxic effects of 3-MF on lung and kidneys are provided. 18 refs

  15. Emerging Role of (EndoCannabinoids in Migraine

    Directory of Open Access Journals (Sweden)

    Pinja Leimuranta

    2018-04-01

    Full Text Available In this mini-review, we summarize recent discoveries and present new hypotheses on the role of cannabinoids in controlling trigeminal nociceptive system underlying migraine pain. Individual sections of this review cover key aspects of this topic, such as: (i the current knowledge on the endocannabinoid system (ECS with emphasis on expression of its components in migraine related structures; (ii distinguishing peripheral from central site of action of cannabinoids, (iii proposed mechanisms of migraine pain and control of nociceptive traffic by cannabinoids at the level of meninges and in brainstem, (iv therapeutic targeting in migraine of monoacylglycerol lipase and fatty acid amide hydrolase, enzymes which control the level of endocannabinoids; (v dual (possibly opposing actions of cannabinoids via anti-nociceptive CB1 and CB2 and pro-nociceptive TRPV1 receptors. We explore the cannabinoid-mediated mechanisms in the frame of the Clinical Endocannabinoid Deficiency (CECD hypothesis, which implies reduced tone of endocannabinoids in migraine patients. We further discuss the control of cortical excitability by cannabinoids via inhibition of cortical spreading depression (CSD underlying the migraine aura. Finally, we present our view on perspectives of Cannabis-derived (extracted or synthetized marijuana components or novel endocannabinoid therapeutics in migraine treatment.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  19. 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.

  20. 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

  1. 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

  2. Endocannabinoids in the Dentate Gyrus

    OpenAIRE

    Frazier, Charles J.

    2007-01-01

    Recent years have produced rapid and enormous growth in our understanding of endocannabinoid-mediated signalling in the CNS. While much of the recent progress has focused on other areas of the brain, a significant body of evidence has developed that indicates the presence of a robust system for endocannabinoid-mediated signalling in the dentate gyrus. This chapter will provide an overview of our current understanding of that system based on available anatomical and physiological data.

  3. Genetic variation in the endocannabinoid degrading enzyme fatty acid amide hydrolase (FAAH) and their influence on weight loss and insulin resistance under a high monounsaturated fat hypocaloric diet.

    Science.gov (United States)

    de Luis, Daniel; Aller, Rocio; Izaola, Olatz; Conde, Rosa; de la Fuente, Beatriz; Gonzalez Sagrado, Manuel

    2013-01-01

    The C385A polymorphism of FAAH gene (rs324420C>A) has been associated with obesity. We investigate the role of this polymorphism on anthropometric and metabolic responses after an enriched monounsaturated fat hypocaloric diet. A sample of 95 obese individuals was analyzed at baseline and after 3 months of an enriched monounsaturated fat hypocaloric diet. Sixty two patients (65.3%) had the genotype C385C and 33 (34.7%) patients had C385A genotype (30 patients, 31.6%) or A358A (3 patients, 3.2%) (A carriers group). In subjects with C385C genotype, insulin (-1.9±5.3 mUI/l) and HOMA-R (-0.48±0.75 U) decreased. In A carriers subjects, the decreases in weight were 3.7±3.4 kg (decrease in C385C genotype group 4.4±3.6 kg), fat mass 2.7±3.2 kg (decrease in C385C genotype group 3.4±3.2 kg) and waist circumference 3.1±3.4cm (decrease in C385 genotype group 4.4±4.6 cm). These changes were significantly higher in the C385C genotype group than the A carriers subjects. After weight loss, noncarriers of the allele A385 of FAAH had an improvement on insulin and HOMA-R levels with an enriched monounsaturated fat hypocaloric diet. A better response of weight, fat mass and waist circumference was observed in C385 genotype subjects than A carriers participants. Copyright © 2013 Elsevier Inc. All rights reserved.

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  6. 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

    Science.gov (United States)

    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

  7. Effects of C358A missense polymorphism of the endocannabinoid degrading enzyme fatty acid amide hydrolase on weight loss after a hypocaloric diet.

    Science.gov (United States)

    de Luis, Daniel Antonio; Gonzalez Sagrado, Manuel; Aller, Rocio; Izaola, Olatz; Conde, Rosa

    2011-05-01

    The Pro129THr, C385A, polymorphism of FAAH gene (rs324420C>A) has been associated with overweight and obesity. We investigate the role of this polymorphism on anthropometric and metabolic responses to a weight loss program. Obese individuals (n = 122) were assessed at baseline and after 3 months of a hypocaloric diet. There were 76.2% (n = 93) homozygotes for the C allele, 23.8% (n = 27) AC heterozygotes, and 1.6% (n = 2) homozygotes for the A allele. After the dietary intervention, all individuals decreased their body weight (in kilograms), body mass index (in kilograms per square meter), fat mass (in kilograms), waist circumference (in centimeters), and systolic blood pressure (in millimeters of mercury). In mutant-type group, the decrease in weight was 3.5 ± 3.6 kg (decrease in wild-type group, 2.4 ± 3.8 kg); and the decrease in waist circumference was 5.4 ± 6.4 cm (decrease in wild-type group, 2.6 ± 4.8 cm). Individuals with the A/C or AA genotype had a significant reduction (P < .05) in glucose (96.5 ± 12.5 vs 92.3 ± 10.5 mg/dL; difference, 2.68 ± 1.81 mg/dL), total cholesterol (215.3 ± 49 vs 193.3 ± 27.6 mg/dL; difference, 14.31 ± 7.21 mg/dL), and low-density lipoprotein cholesterol (133.6 ± 53 vs 106.7 ± 39.2 mg/dL; difference, 15.87 ± 9.61 mg/dL) levels. The A allele at rs324420 in the FAAH gene was associated with larger improvements in glucose, total cholesterol, low-density lipoprotein cholesterol, body mass, and waist circumference after a dietary intervention. Copyright © 2011 Elsevier Inc. All rights reserved.

  8. The endocannabinoid system within the dorsal lateral geniculate nucleus of the vervet monkey

    DEFF Research Database (Denmark)

    Javadi, P.; Bouskila, J.; Bouchard, J. -F.

    2015-01-01

    The endocannabinoid system mainly consists of cannabinoid receptors type 1 (CB1R) and type 2 (CB2R), their endogenous ligands termed endocannabinoids (eCBs), and the enzymes responsible for the synthesis and degradation of eCBs. These cannabinoid receptors have been well characterized in rodent a...... layers may explain some of the behavioral effects of cannabinoids associated with the integrity of the dorsal visual pathway that plays a role in visual-spatial localization and motion perception....

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

    Science.gov (United States)

    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.

  10. 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.

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

    African Journals Online (AJOL)

    Jane

    2010-10-11

    Oct 11, 2010 ... In this work, we first introduced the enzyme parameter (ɑ) into the kinetic equations and consequently established an in silico glycolysis model of Saccharomyces cerevisiae in XML format (Figure 1), based on the work of Hynn et al. (2001). Equation 1 shows how the ɑis introduced into the kinetic equation.

  12. Oxyradical Stress, Endocannabinoids, and Atherosclerosis

    Directory of Open Access Journals (Sweden)

    Anberitha T. Matthews

    2015-12-01

    Full Text Available Atherosclerosis is responsible for most cardiovascular disease (CVD and is caused by several factors including hypertension, hypercholesterolemia, and chronic inflammation. Oxidants and electrophiles have roles in the pathophysiology of atherosclerosis and the concentrations of these reactive molecules are an important factor in disease initiation and progression. Overactive NADPH oxidase (Nox produces excess superoxide resulting in oxidized macromolecules, which is an important factor in atherogenesis. Although superoxide and reactive oxygen species (ROS have obvious toxic properties, they also have fundamental roles in signaling pathways that enable cells to adapt to stress. In addition to inflammation and ROS, the endocannabinoid system (eCB is also important in atherogenesis. Linkages have been postulated between the eCB system, Nox, oxidative stress, and atherosclerosis. For instance, CB2 receptor-evoked signaling has been shown to upregulate anti-inflammatory and anti-oxidative pathways, whereas CB1 signaling appears to induce opposite effects. The second messenger lipid molecule diacylglycerol is implicated in the regulation of Nox activity and diacylglycerol lipase β (DAGLβ is a key biosynthetic enzyme in the biosynthesis eCB ligand 2-arachidonylglycerol (2-AG. Furthermore, Nrf2 is a vital transcription factor that protects against the cytotoxic effects of both oxidant and electrophile stress. This review will highlight the role of reactive oxygen species (ROS in intracellular signaling and the impact of deregulated ROS-mediated signaling in atherogenesis. In addition, there is also emerging knowledge that the eCB system has an important role in atherogenesis. We will attempt to integrate oxidative stress and the eCB system into a conceptual framework that provides insights into this pathology.

  13. Characterisation of a major enzyme of bovine nitrogen metabolism

    CSIR Research Space (South Africa)

    Mathomu, LM

    2010-09-01

    Full Text Available of cellular protein metabolism (Curthoys & Watford, 1995; Meister, 1974). Glutamine functions as a major inter-organ transport form of nitrogen, carbon and serves as a source of energy between tissues such as brain, liver, kidney and even muscles...

  14. Characterization of Carbohydrate Active Enzymes Involved in Arabinogalactan Protein Metabolism

    DEFF Research Database (Denmark)

    Knoch, Eva

    and tissues, their functions and synthesis are still poorly understood. The aim of the research presented in the thesis was to characterize carbohydrate active enzymes involved in AGP biosynthesis and modification to gain insights into the biosynthesis of the glycoproteins in plants. Candidate...... glycosyltransferases and glycoside hydrolases were selected based on co-expression profiles from a transcriptomics analysis. Reverse genetics approach on a novel glucuronosyltransferase involved in AGP biosynthesis has revealed that the enzyme activity is required for normal cell elongation in etiolated seedlings....... The enzymatic activity of a hydrolase from GH family 17 was investigated, without successful determination of the activity. Members of hydrolase family 43 appeared to be localized in the Golgi-apparatus, which is also the compartment for glycan biosynthesis. The localization of these glycoside hydrolases...

  15. Care and feeding of the endocannabinoid system: a systematic review of potential clinical interventions that upregulate the endocannabinoid system.

    Science.gov (United States)

    McPartland, John M; Guy, Geoffrey W; Di Marzo, Vincenzo

    2014-01-01

    The "classic" endocannabinoid (eCB) system includes the cannabinoid receptors CB1 and CB2, the eCB ligands anandamide (AEA) and 2-arachidonoylglycerol (2-AG), and their metabolic enzymes. An emerging literature documents the "eCB deficiency syndrome" as an etiology in migraine, fibromyalgia, irritable bowel syndrome, psychological disorders, and other conditions. We performed a systematic review of clinical interventions that enhance the eCB system--ways to upregulate cannabinoid receptors, increase ligand synthesis, or inhibit ligand degradation. We searched PubMed for clinical trials, observational studies, and preclinical research. Data synthesis was qualitative. Exclusion criteria limited the results to 184 in vitro studies, 102 in vivo animal studies, and 36 human studies. Evidence indicates that several classes of pharmaceuticals upregulate the eCB system, including analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids, glucocorticoids), antidepressants, antipsychotics, anxiolytics, and anticonvulsants. Clinical interventions characterized as "complementary and alternative medicine" also upregulate the eCB system: massage and manipulation, acupuncture, dietary supplements, and herbal medicines. Lifestyle modification (diet, weight control, exercise, and the use of psychoactive substances--alcohol, tobacco, coffee, cannabis) also modulate the eCB system. Few clinical trials have assessed interventions that upregulate the eCB system. Many preclinical studies point to other potential approaches; human trials are needed to explore these promising interventions.

  16. Care and feeding of the endocannabinoid system: a systematic review of potential clinical interventions that upregulate the endocannabinoid system.

    Directory of Open Access Journals (Sweden)

    John M McPartland

    Full Text Available The "classic" endocannabinoid (eCB system includes the cannabinoid receptors CB1 and CB2, the eCB ligands anandamide (AEA and 2-arachidonoylglycerol (2-AG, and their metabolic enzymes. An emerging literature documents the "eCB deficiency syndrome" as an etiology in migraine, fibromyalgia, irritable bowel syndrome, psychological disorders, and other conditions. We performed a systematic review of clinical interventions that enhance the eCB system--ways to upregulate cannabinoid receptors, increase ligand synthesis, or inhibit ligand degradation.We searched PubMed for clinical trials, observational studies, and preclinical research. Data synthesis was qualitative. Exclusion criteria limited the results to 184 in vitro studies, 102 in vivo animal studies, and 36 human studies. Evidence indicates that several classes of pharmaceuticals upregulate the eCB system, including analgesics (acetaminophen, non-steroidal anti-inflammatory drugs, opioids, glucocorticoids, antidepressants, antipsychotics, anxiolytics, and anticonvulsants. Clinical interventions characterized as "complementary and alternative medicine" also upregulate the eCB system: massage and manipulation, acupuncture, dietary supplements, and herbal medicines. Lifestyle modification (diet, weight control, exercise, and the use of psychoactive substances--alcohol, tobacco, coffee, cannabis also modulate the eCB system.Few clinical trials have assessed interventions that upregulate the eCB system. Many preclinical studies point to other potential approaches; human trials are needed to explore these promising interventions.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

  19. Astrocytes in endocannabinoid signalling.

    Science.gov (United States)

    Navarrete, Marta; Díez, Adolfo; Araque, Alfonso

    2014-10-19

    Astrocytes are emerging as integral functional components of synapses, responding to synaptically released neurotransmitters and regulating synaptic transmission and plasticity. Thus, they functionally interact with neurons establishing tripartite synapses: a functional concept that refers to the existence of communication between astrocytes and neurons and its crucial role in synaptic function. Here, we discuss recent evidence showing that astrocytes are involved in the endocannabinoid (ECB) system, responding to exogenous cannabinoids as well as ECBs through activation of type 1 cannabinoid receptors, which increase intracellular calcium and stimulate the release of glutamate that modulates synaptic transmission and plasticity. We also discuss the consequences of ECB signalling in tripartite synapses on the astrocyte-mediated regulation of synaptic function, which reveal novel properties of synaptic regulation by ECBs, such as the spatially controlled dual effect on synaptic strength and the lateral potentiation of synaptic efficacy. Finally, we discuss the potential implications of ECB signalling for astrocytes in brain pathology and animal behaviour. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  20. Molecular components and functions of the endocannabinoid system in mouse prefrontal cortex.

    Directory of Open Access Journals (Sweden)

    Mathieu Lafourcade

    2007-08-01

    Full Text Available Cannabinoids have deleterious effects on prefrontal cortex (PFC-mediated functions and multiple evidences link the endogenous cannabinoid (endocannabinoid system, cannabis use and schizophrenia, a disease in which PFC functions are altered. Nonetheless, the molecular composition and the physiological functions of the endocannabinoid system in the PFC are unknown.Here, using electron microscopy we found that key proteins involved in endocannabinoid signaling are expressed in layers v/vi of the mouse prelimbic area of the PFC: presynaptic cannabinoid CB1 receptors (CB1R faced postsynaptic mGluR5 while diacylglycerol lipase alpha (DGL-alpha, the enzyme generating the endocannabinoid 2-arachidonoyl-glycerol (2-AG was expressed in the same dendritic processes as mGluR5. Activation of presynaptic CB1R strongly inhibited evoked excitatory post-synaptic currents. Prolonged synaptic stimulation at 10Hz induced a profound long-term depression (LTD of layers V/VI excitatory inputs. The endocannabinoid -LTD was presynaptically expressed and depended on the activation of postsynaptic mGluR5, phospholipase C and a rise in postsynaptic Ca(2+ as predicted from the localization of the different components of the endocannabinoid system. Blocking the degradation of 2-AG (with URB 602 but not of anandamide (with URB 597 converted subthreshold tetanus to LTD-inducing ones. Moreover, inhibiting the synthesis of 2-AG with Tetrahydrolipstatin, blocked endocannabinoid-mediated LTD. All together, our data show that 2-AG mediates LTD at these synapses.Our data show that the endocannabinoid -retrograde signaling plays a prominent role in long-term synaptic plasticity at the excitatory synapses of the PFC. Alterations of endocannabinoid -mediated synaptic plasticity may participate to the etiology of PFC-related pathologies.

  1. 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 .

  2. 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.

  3. Endocannabinoid signaling in reward and addiction

    Science.gov (United States)

    Parsons, Loren H.; Hurd, Yasmin L.

    2015-01-01

    Brain endocannabinoid signaling influences the motivation for natural rewards (such as palatable food, sexual activity and social interaction) and modulates the rewarding effects of addictive drugs. Pathological forms of natural and drug-induced reward are associated with dysregulated endocannabinoid signaling that may derive from pre-existing genetic factors or from prolonged drug exposure. Impaired endocannabinoid signaling contributes to dysregulated synaptic plasticity, increased stress responsivity, negative emotional states, and craving that propel addiction. Understanding the contributions of endocannabinoid disruptions to behavioral and physiological traits provides insight into the endocannabinoid influence on addiction vulnerability. PMID:26373473

  4. Multifaceted roles of metabolic enzymes of the Paracoccidioides species complex

    Directory of Open Access Journals (Sweden)

    Caroline Maria Marcos

    2014-12-01

    Full Text Available Paracoccidioides species are dimorphic fungi, and are the etiologic agents of paracoccidioidomycosis (PCM, a serious disease of multiple organs. The large number of tissues colonized by this fungus suggests the presence of a variety of surface molecules involved in adhesion. A surprising finding is that the majority of enzymes in the glycolytic pathway, tricarboxylic acid (TCA cycle and glyoxylate cycle in Paracoccidioides spp. has adhesive properties that aid in the interaction with the host extracellular matrix, and so act as ‘moonlighting’ proteins. Moonlighting proteins have multiple functions and add another dimension to cellular complexity, while benefiting cells in several ways. This phenomenon occurs in both eukaryotes and prokaryotes. For example, moonlighting proteins from the glycolytic pathway or TCA cycle can play roles in bacterial pathogens, either by acting as proteins secreted in a conventional pathway or not and/or as cell surface component that facilitate adhesion or adherence . This review outlines the multifuncionality exposed by a variety of Paracoccidioides spp. enzymes including aconitase, aldolase, glyceraldehyde-3-phosphate dehydrogenase, isocitrate lyase, malate synthase, triose phosphate isomerase, fumarase and enolase. The roles that moonlighting activities play in the virulence characteristics of this fungus and several other human pathogens during their interactions with the host are discussed.

  5. Lipidomic Analysis of Endocannabinoid Signaling: Targeted Metabolite Identification and Quantification

    Directory of Open Access Journals (Sweden)

    Jantana Keereetaweep

    2016-01-01

    Full Text Available The endocannabinoids N-arachidonoylethanolamide (or anandamide, AEA and 2-arachidonoylglycerol (2-AG belong to the larger groups of N-acylethanolamines (NAEs and monoacylglycerol (MAG lipid classes, respectively. They are biologically active lipid molecules that activate G-protein-coupled cannabinoid receptors found in various organisms. After AEA and 2-AG were discovered in the 1990s, they have been extensively documented to have a broad range of physiological functions. Along with AEA, several NAEs, for example, N-palmitoylethanolamine (PEA, N-stearoylethanolamine (SEA, and N-oleoylethanolamine (OEA are also present in tissues, usually at much larger concentrations than AEA. Any perturbation that involves the endocannabinoid pathway may subsequently alter basal level or metabolism of these lipid mediators. Further, the altered levels of these molecules often reflect pathological conditions associated with tissue damage. Robust and sensitive methodologies to analyze these lipid mediators are essential to understanding how they act as endocannabinoids. The recent advances in mass spectrometry allow researchers to develop lipidomics approaches and several methodologies have been proposed to quantify endocannabinoids in various biological systems.

  6. Cannabis and endocannabinoid modulators: Therapeutic promises and challenges

    Science.gov (United States)

    Grant, Igor; Cahn, B. Rael

    2008-01-01

    The discovery that botanical cannabinoids such as delta-9 tetrahydrocannabinol exert some of their effect through binding specific cannabinoid receptor sites has led to the discovery of an endocannabinoid signaling system, which in turn has spurred research into the mechanisms of action and addiction potential of cannabis on the one hand, while opening the possibility of developing novel therapeutic agents on the other. This paper reviews current understanding of CB1, CB2, and other possible cannabinoid receptors, their arachidonic acid derived ligands (e.g. anandamide; 2 arachidonoyl glycerol), and their possible physiological roles. CB1 is heavily represented in the central nervous system, but is found in other tissues as well; CB2 tends to be localized to immune cells. Activation of the endocannabinoid system can result in enhanced or dampened activity in various neural circuits depending on their own state of activation. This suggests that one function of the endocannabinoid system may be to maintain steady state. The therapeutic action of botanical cannabis or of synthetic molecules that are agonists, antagonists, or which may otherwise modify endocannabinoid metabolism and activity indicates they may have promise as neuroprotectants, and may be of value in the treatment of certain types of pain, epilepsy, spasticity, eating disorders, inflammation, and possibly blood pressure control. PMID:18806886

  7. Peripheral Endocannabinoid System Activity in Patients Treated With Sibutramine

    Science.gov (United States)

    Engeli, Stefan; Heusser, Karsten; Janke, Jürgen; Gorzelniak, Kerstin; Bátkai, Sándor; Pacher, Pál; Harvey-White, Judith; Luft, Friedrich C.; Jordan, Jens

    2008-01-01

    Objective The endocannabinoid system (ECS) promotes weight gain and obesity-associated metabolic changes. Weight loss interventions may influence obesity-associated risk indirectly through modulation of the peripheral ECS. We investigated the effect of acute and chronic treatment with sibutramine on components of the peripheral ECS. Methods and Procedures Twenty obese otherwise healthy patients received randomized, double-blind, crossover treatment with placebo and 15 mg/day sibutramine for 5 days each, followed by 12 weeks open-label sibutramine treatment. We determined circulating anandamide and 2-arachidonoylglycerol and expression levels of endocannabinoid genes in subcutaneous abdominal adipose tissue biopsies. Results Body weight was stable during the acute treatment period and decreased by 6.0 ± 0.8 kg in those patients completing 3 months of sibutramine treatment (P sibutramine treatment. Discussion The ECS is activated in obesity. We did not find any influence of 5% body weight loss induced by sibutramine on circulating levels of endocannabinoids and adipose-tissue expression of endocannabinoid genes in obese subjects. These data confirm our previous findings on dietary weight loss and suggest that the dysregulation of the ECS may be a cause rather than a consequence of obesity. PMID:18356837

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

    International Nuclear Information System (INIS)

    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

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

    Directory of Open Access Journals (Sweden)

    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

  10. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  12. 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

    2016-02-01

    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.

  13. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  15. 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...

  16. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  18. Endocannabinoid system: Role in depression, reward and pain control (Review).

    Science.gov (United States)

    Huang, Wen-Juan; Chen, Wei-Wei; Zhang, Xia

    2016-10-01

    Depression and pain co-exist in almost 80% of patients and are associated with impaired health-related quality of life, often contributing to high mortality. However, the majority of patients who suffer from the comorbid depression and pain are not responsive to pharmacological treatments that address either pain or depression, making this comorbidity disorder a heavy burden on patients and society. In ancient times, this depression-pain comorbidity was treated using extracts of the Cannabis sativa plant, known now as marijuana and the mode of action of Δ9‑tetrahydrocannabinol, the active cannabinoid ingredient of marijuana, has only recently become known, with the identification of cannabinoid receptor type 1 (CB1) and CB2. Subsequent investigations led to the identification of endocannabinoids, anandamide and 2-arachidonoylglycerol, which exert cannabinomimetic effects through the CB1 and CB2 receptors, which are located on presynaptic membranes in the central nervous system and in peripheral tissues, respectively. These endocannabinoids are produced from membrane lipids and are lipohilic molecules that are synthesized on demand and are eliminated rapidly after their usage by hydrolyzing enzymes. Clinical studies revealed altered endocannabinoid signaling in patients with chronic pain. Considerable evidence suggested the involvement of the endocannabinoid system in eliciting potent effects on neurotransmission, neuroendocrine, and inflammatory processes, which are known to be deranged in depression and chronic pain. Several synthetic cannabinomimetic drugs are being developed to treat pain and depression. However, the precise mode of action of endocannabinoids on different targets in the body and whether their effects on pain and depression follow the same or different pathways, remains to be determined.

  19. Enzyme

    Science.gov (United States)

    Enzymes are complex proteins that cause a specific chemical change in all parts of the body. For ... use them. Blood clotting is another example of enzymes at work. Enzymes are needed for all body ...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  2. 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

  3. 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...

  4. 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

  5. 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

  6. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

  8. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Metabolic Effects of n-3 PUFA as Phospholipids Are Superior to Triglycerides in Mice Fed a High-Fat Diet: Possible Role of Endocannabinoids

    Czech Academy of Sciences Publication Activity Database

    Rossmeisl, Martin; Macek Jílková, Zuzana; Kuda, Ondřej; Jeleník, Tomáš; Medříková, Daša; Staňková, B.; Kristinsson, B.; Haraldsson, G.G.; Svensen, H.; Stoknes, I.; Sjövall, P.; Magnusson, Y.; Balvers, M.G.J.; Verhoeckx, K.C.M.; Tvrzická, E.; Bryhn, M.; Kopecký, Jan

    2012-01-01

    Roč. 7, č. 6 (2012), e38834 E-ISSN 1932-6203 R&D Projects: GA MZd(CZ) NS10528; GA ČR(CZ) GAP301/10/1420 Institutional research plan: CEZ:AV0Z50110509 Institutional support: RVO:67985823 Keywords : n-3 PUFA * marine phospholipids * obesity * insulin resistance Subject RIV: FB - Endocrinology, Diabetology, Metabolism, Nutrition Impact factor: 3.730, year: 2012

  11. Perinatal asphyxia results in altered expression of the hippocampal acylethanolamide/endocannabinoid signaling system associated to memory impairments in postweaned rats.

    Science.gov (United States)

    Blanco, Eduardo; Galeano, Pablo; Holubiec, Mariana I; Romero, Juan I; Logica, Tamara; Rivera, Patricia; Pavón, Francisco J; Suarez, Juan; Capani, Francisco; Rodríguez de Fonseca, Fernando

    2015-01-01

    Perinatal asphyxia (PA) is an obstetric complication that strongly affects the CNS. The endocannabinoid system (ECS) is a lipid transmitter system involved in several physiological processes including synaptic plasticity, neurogenesis, memory, and mood. Endocannabinoids, and other acylethanolamides (AEs) without endocannabinoid activity, have recently received growing attention due to their potential neuroprotective functions in neurological disorders, including cerebral ischemia. In the present study, we aimed to analyze the changes produced by PA in the major metabolic enzymes and receptors of the ECS/AEs in the hippocampus using a rodent model of PA. To induce PA, we removed uterine horns from ready-to-deliver rats and immersed them into a water bath during 19 min. Animals delivered spontaneously or by cesarean section were employed as controls. At 1 month of age, cognitive functions were assessed and immunohistochemical procedures were carried out to determine the expression of NeuN and glial fibrillary acidic protein, enzymes responsible for synthesis (DAGLα and NAPE-PLD) and degradation (FAAH) of ECS/AEs and their receptors (CB1 and PPARα) in the hippocampus. Postweaned asphyctic rats showed impaired recognition and spatial reference memory that were accompanied by hippocampal astrogliosis and changes in the expression of enzymes and receptors. The most remarkable findings in asphyctic rats were a decrease in the expression of NAPE-PLD and PPARα in both hippocampal areas CA1 and CA3. In addition, postweaned cesarean delivery rats showed an increase in the immunolabeling for FAAH in the hippocampal CA3 area. Since, NAPE-PLD and PPARα are proteins that participate in the biochemical process of AEs, specially the neuroprotective oleoylethanolamide, these results suggest that PA dysregulates this system. These data encourage conducting future studies using AEs as potential neuroprotective compounds in animal models of PA.

  12. Perinatal asphyxia results in altered expression of the hippocampal acylethanolamide/endocannabinoid signaling system associated to memory impairments in postweaned rats

    Directory of Open Access Journals (Sweden)

    Eduardo eBlanco Calvo

    2015-11-01

    Full Text Available Perinatal asphyxia (PA is an obstetric complication that strongly affects the CNS. The endocannabinoid system (ECS is a lipid transmitter system involved in several physiological processes including synaptic plasticity, neurogenesis, memory and mood. Endocannabinoids, and other acylethanolamides (AEs without endocannabinoid activity, have recently received growing attention as they have potential neuroprotective functions in neurological disorders, including cerebral ischemia. In the present study, we aimed to analyze the changes produced by PA in the major metabolic enzymes and receptors of the ECS/AEs in the hippocampus using a rodent model of PA. To induce PA, we removed uterine horns from ready-to-deliver rats and immersed them into a water bath during 19 min. Animals that were delivered spontaneously or by caesarean section were employed as controls. At one month of age, cognitive functions were assessed and immunohistochemical procedures were carried out to determine the expression of NeuN and GFAP, enzymes responsible for synthesis (DAGLα and NAPE-PLD and degradation (FAAH of ECS/AEs and their receptors (CB1 and PPARα in the hippocampus. Postweaned asphyctic rats showed impaired recognition and spatial reference memory that were accompanied by hippocampal astrogliosis and changes in the expression of enzymes and receptors. The most remarkable findings in asphyctic rats were a decrease in the expression of NAPE-PLD and PPARα in both hippocampal areas CA1 and CA3. In addition, postweaned cesarean delivery rats showed an increase in the immunolabeling for FAAH in the hippocampal CA3 area. Since NAPE-PLD and PPARα are proteins that participate in the biochemical process of AEs, specially the neuroprotective oleoylethanolamide, these results suggest that PA dysregulates this system. These data encourage conducting future studies using AEs as potential neuroprotective compounds in animal models of PA.

  13. Genetic Polymorphism of Folate and Methionine Metabolizing Enzymes and their Susceptibility to Malignant Lymphoma

    International Nuclear Information System (INIS)

    Habib, E.E.; Aziz, M.; Kotb, M.

    2005-01-01

    Folate and methionine metabolism is involved in DNA synthesis and methylation. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In the present study, 2 polymorphisms were evaluated for a folate metabolic enzyme, methylene-tetrahydrofolate reductase (MTHFR), and one was evaluated for methionine synthase (MS). The 2 polymorphisms MTHFR 677 C-7T and MTHFR 1298 A-7C, are reported to reduce the enzyme activity, which causes intracellular accumulation of 5, 10 vm ethylene-tetrahydrofolate and results in a reduced incidence of DNA double strand breakage. The MS 2756 A-7G polymorphism also reduces the enzyme activity and results in the hypo methylation of DNA. Patients and Methods: To test this hypothesis, genetic polymorphisms in the folate metabolic pathway were investigated using the DNA from a case-control study on 31 patients having malignant lymphoma from the Oncology Outpatient Clinic of the New Children's Hospital, Cairo University and 30 controls who were actually normal children attending for vaccination to the same hospital. We found that there is a higher susceptibility with the MTHFR 677CC and MTHFR 1298 AA genotypes (OR=4.3, 95% CI 1.12-16). When those harbor at least one variant allele in either polymorphism of MTHFR they were defined as reference. For the MS 2756 AG genotype polymorphism there was also a higher susceptibility to developing malignant lymphoma (OR=2.6; 95% CI 1.16.4). Results suggest that folate and methionine metabolism may play an important role in the pathogenesis of malignant lymphoma. Further studies to confirm this association and detailed biologic mechanisms are now required

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

    Science.gov (United States)

    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

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

    Science.gov (United States)

    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.

  16. Gestation Related Gene Expression of the Endocannabinoid Pathway in Rat Placenta

    Directory of Open Access Journals (Sweden)

    Kanchan Vaswani

    2015-01-01

    Full Text Available Mammalian placentation is a vital facet of the development of a healthy and viable offspring. Throughout gestation the placenta changes to accommodate, provide for, and meet the demands of a growing fetus. Gestational gene expression is a crucial part of placenta development. The endocannabinoid pathway is activated in the placenta and decidual tissues throughout pregnancy and aberrant endocannabinoid signaling during the period of placental development has been associated with pregnancy disorders. In this study, the gene expression of eight endocannabinoid system enzymes was investigated throughout gestation. Rat placentae were obtained at E14.25, E15.25, E17.25, and E20, RNA was extracted, and microarray was performed. Gene expression of enzymes Faah, Mgll, Plcd4, Pld1, Nat1, Daglα, and Ptgs2 was studied (cohort 1, microarray. Biological replication of the results was performed by qPCR (cohort 2. Four genes showed differential expression (Mgll, Plcd4, Ptgs2, and Pld1, from mid to late gestation. Genes positively associated with gestational age were Ptgs2, Mgll, and Pld1, while Plcd4 was downregulated. This is the first comprehensive study that has investigated endocannabinoid pathway gene expression during rat pregnancy. This study provides the framework for future studies that investigate the role of endocannabinoid system during pregnancy.

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  19. Essential fatty acids and lipid mediators. Endocannabinoids

    Directory of Open Access Journals (Sweden)

    G. Caramia

    2012-03-01

    Full Text Available In 1929 Burr and Burr discovered the essential fatty acids omega-6 and omega-3. Since then, researchers have shown a growing interest in polyunsaturated fatty acids (PUFA as precursors of “lipid mediator” molecules, often with opposing effects, prostaglandins, prostacyclins, thromboxanes, leukotrienes, lipossines, resolvines, protectines, maresins that regulate immunity, platelet aggregation, inflammation, etc. They showed that the balance between omega-3 and omega-6 acids has a profound influence on all the body’s inflammatory responses and a raised level of PUFA omega-3 in tissue correlate with a reduced incidence of degenerative cardiovascular disease, some mental illnesses such as depression, and neuro-degenerative diseases such as Alzheimer’s. The CYP-catalyzed epoxidation and hydroxylation of arachidonic acid (AA were established recently as the so-called third branch of AGE cascade. Cytochrome P450 (CYP epoxygenases convert AA to four epoxyeicosatrienoic acid (EET regioisomers, that produce vascular relaxation anti-inflammatory effects on blood vessels and in the kidney, promote angiogenesis, and protect ischemic myocardium and brain. Eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA are accessible to CYP enzymes in the same way as AA. Metabolites derived from EPA include epoxyeicosatetraenoic acids (EETR and hydroxyeicosapentaenoic acids (19- and 20-HEPE, whereas DHA include epoxydocosapentaenoic acids (EDPs hydroxydocosahexaenoic acids (21- and 22-HDoHE. For many of the CYP isoforms, the n-3 PUFAs are the preferred substrates and the available data suggest that some of the vasculo- and cardioprotective effects attributed to dietary n-3 PUFAs may be mediated by CYP-dependent metabolites of EPA and DHA. From AA derives also endocannabinoids like anandamide (N-arachidonoylethanolamine and 2-arachidonoylglycerol, capable of mimicking the pharmacological actions of the active principle of Cannabis sativa preparations such as

  20. 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...

  1. 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

  2. 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...

  3. Endocannabinoid System: A Multi-Facet Therapeutic Target.

    Science.gov (United States)

    Kaur, Rimplejeet; Ambwani, Sneha R; Singh, Surjit

    2016-01-01

    Cannabis sativa is also popularly known as marijuana. It has been cultivated and used by man for recreational and medicinal purposes since many centuries. Study of cannabinoids was at bay for very long time and its therapeutic value could not be adequately harnessed due to its legal status as proscribed drug in most of the countries. The research of drugs acting on endocannabinoid system has seen many ups and downs in the recent past. Presently, it is known that endocannabinoids has role in pathology of many disorders and they also serve "protective role" in many medical conditions. Several diseases like emesis, pain, inflammation, multiple sclerosis, anorexia, epilepsy, glaucoma, schizophrenia, cardiovascular disorders, cancer, obesity, metabolic syndrome related diseases, Parkinson's disease, Huntington's disease, Alzheimer's disease and Tourette's syndrome could possibly be treated by drugs modulating endocannabinoid system. Presently, cannabinoid receptor agonists like nabilone and dronabinol are used for reducing the chemotherapy induced vomiting. Sativex (cannabidiol and THC combination) is approved in the UK, Spain and New Zealand to treat spasticity due to multiple sclerosis. In US it is under investigation for cancer pain, another drug Epidiolex (cannabidiol) is also under investigation in US for childhood seizures. Rimonabant, CB1 receptor antagonist appeared as a promising anti-obesity drug during clinical trials but it also exhibited remarkable psychiatric side effect profile. Due to which the US Food and Drug Administration did not approve Rimonabant in US. It sale was also suspended across the EU in 2008. Recent discontinuation of clinical trial related to FAAH inhibitor due to occurrence of serious adverse events in the participating subjects could be discouraging for the research fraternity. Despite some mishaps in clinical trials related to drugs acting on endocannabinoid system, still lot of research is being carried out to explore and establish

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

    Science.gov (United States)

    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.

  5. 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.

  6. 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...

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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

  9. Endocannabinoid antagonism: blocking the excess in the treatment of high-risk abdominal obesity.

    Science.gov (United States)

    Duffy, Danielle; Rader, Daniel

    2007-02-01

    Abdominal obesity is a prevalent, worldwide problem linked to cardiometabolic comorbidities and an increased risk of coronary heart disease. First-line therapy to reduce such risk revolves around diet and exercise; however, such changes are often difficult to implement and unsuccessful. Understanding the underlying pathophysiology of underlying metabolic derangements could provide new targets for pharmacologic therapy. One system that has gained recent attention is the endocannabinoid system. The endocannabinoid system has a significant role in central appetite control and peripheral lipogenesis and is up-regulated in diet-induced obesity. Rimonabant is a selective cannabinoid-1 receptor antagonist and is the first compound of its type to test the hypothesis that down-regulating an overactive endocannabinoid system could have therapeutic benefit not only for weight loss but also for the atherogenic dyslipidemia and insulin resistance that cluster with abdominal obesity in particular. Animal models have been critical for elucidating the role of the endocannabinoid system in obesity and in demonstrating that antagonism with rimonabant can induce loss of visceral fat and improve insulin sensitivity. Early human trials with rimonabant have confirmed significant reductions in weight, as well as favorable changes in atherogenic dyslipidemia, insulin resistance, and markers of inflammation. Interestingly, some of these beneficial metabolic effects are partially weight-loss-independent, confirming the importance of peripheral endocannabinoid system effects in addition to central effects.

  10. Enhancement of endocannabinoid signaling protects against cocaine-induced neurotoxicity

    International Nuclear Information System (INIS)

    Vilela, Luciano R.; Gobira, Pedro H.; Viana, Thercia G.; Medeiros, Daniel C.; Ferreira-Vieira, Talita H.; Doria, Juliana G.; Rodrigues, Flávia; Aguiar, Daniele C.; Pereira, Grace S.; Massessini, André R.; Ribeiro, Fabíola M.; Oliveira, Antonio Carlos P. de; Moraes, Marcio F.D.; Moreira, Fabricio A.

    2015-01-01

    Cocaine is an addictive substance with a potential to cause deleterious effects in the brain. The strategies for treating its neurotoxicity, however, are limited. Evidence suggests that the endocannabinoid system exerts neuroprotective functions against various stimuli. Thus, we hypothesized that inhibition of fatty acid amide hydrolase (FAAH), the main enzyme responsible for terminating the actions of the endocannabinoid anandamide, reduces seizures and cell death in the hippocampus in a model of cocaine intoxication. Male Swiss mice received injections of endocannabinoid-related compounds followed by the lowest dose of cocaine that induces seizures, electroencephalographic activity and cell death in the hippocampus. The molecular mechanisms were studied in primary cell culture of this structure. The FAAH inhibitor, URB597, reduced cocaine-induced seizures and epileptiform electroencephalographic activity. The cannabinoid CB 1 receptor selective agonist, ACEA, mimicked these effects, whereas the antagonist, AM251, prevented them. URB597 also inhibited cocaine-induced activation and death of hippocampal neurons, both in animals and in primary cell culture. Finally, we investigated if the PI3K/Akt/ERK intracellular pathway, a cell surviving mechanism coupled to CB 1 receptor, mediated these neuroprotective effects. Accordingly, URB597 injection increased ERK and Akt phosphorylation in the hippocampus. Moreover, the neuroprotective effect of this compound was reversed by the PI3K inhibitor, LY294002. In conclusion, the pharmacological facilitation of the anandamide/CB1/PI3K signaling protects the brain against cocaine intoxication in experimental models. This strategy may be further explored in the development of treatments for drug-induced neurotoxicity. - Highlights: • Cocaine toxicity is characterized by seizures and hippocampal cell death. • The endocannabinoid anandamide acts as a brain protective mechanism. • Inhibition of anandamide hydrolysis attenuates

  11. Enhancement of endocannabinoid signaling protects against cocaine-induced neurotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Vilela, Luciano R. [Graduate Program in Neuroscience, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Gobira, Pedro H.; Viana, Thercia G. [Department of Pharmacology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Medeiros, Daniel C.; Ferreira-Vieira, Talita H. [Department of Physiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Doria, Juliana G. [Graduate Program in Neuroscience, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Rodrigues, Flávia [Department of Biochemistry and Immunology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Aguiar, Daniele C. [Department of Pharmacology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Pereira, Grace S.; Massessini, André R. [Department of Physiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Ribeiro, Fabíola M. [Department of Biochemistry and Immunology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Oliveira, Antonio Carlos P. de [Department of Pharmacology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Moraes, Marcio F.D., E-mail: mfdm@icb.ufmg.br [Department of Physiology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil); Moreira, Fabricio A., E-mail: fabriciomoreira@icb.ufmg.br [Department of Pharmacology, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, MG (Brazil)

    2015-08-01

    Cocaine is an addictive substance with a potential to cause deleterious effects in the brain. The strategies for treating its neurotoxicity, however, are limited. Evidence suggests that the endocannabinoid system exerts neuroprotective functions against various stimuli. Thus, we hypothesized that inhibition of fatty acid amide hydrolase (FAAH), the main enzyme responsible for terminating the actions of the endocannabinoid anandamide, reduces seizures and cell death in the hippocampus in a model of cocaine intoxication. Male Swiss mice received injections of endocannabinoid-related compounds followed by the lowest dose of cocaine that induces seizures, electroencephalographic activity and cell death in the hippocampus. The molecular mechanisms were studied in primary cell culture of this structure. The FAAH inhibitor, URB597, reduced cocaine-induced seizures and epileptiform electroencephalographic activity. The cannabinoid CB{sub 1} receptor selective agonist, ACEA, mimicked these effects, whereas the antagonist, AM251, prevented them. URB597 also inhibited cocaine-induced activation and death of hippocampal neurons, both in animals and in primary cell culture. Finally, we investigated if the PI3K/Akt/ERK intracellular pathway, a cell surviving mechanism coupled to CB{sub 1} receptor, mediated these neuroprotective effects. Accordingly, URB597 injection increased ERK and Akt phosphorylation in the hippocampus. Moreover, the neuroprotective effect of this compound was reversed by the PI3K inhibitor, LY294002. In conclusion, the pharmacological facilitation of the anandamide/CB1/PI3K signaling protects the brain against cocaine intoxication in experimental models. This strategy may be further explored in the development of treatments for drug-induced neurotoxicity. - Highlights: • Cocaine toxicity is characterized by seizures and hippocampal cell death. • The endocannabinoid anandamide acts as a brain protective mechanism. • Inhibition of anandamide hydrolysis

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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

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

    Science.gov (United States)

    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

  18. 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

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

    Science.gov (United States)

    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.

  20. 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.

    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.

  1. 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.

  2. Acylethanolamides and endocannabinoid signaling system in dorsal striatum of rats exposed to perinatal asphyxia.

    Science.gov (United States)

    Holubiec, Mariana I; Romero, Juan I; Blanco, Eduardo; Tornatore, Tamara Logica; Suarez, Juan; Rodríguez de Fonseca, Fernando; Galeano, Pablo; Capani, Francisco

    2017-07-13

    Endocannabinoids (eCBs) and acylethanolamides (AEs) have lately received more attention due to their neuroprotective functions in neurological disorders. Here we analyze the alterations induced by perinatal asphyxia (PA) in the main metabolic enzymes and receptors of the eCBs/AEs in the dorsal striatum of rats. To induce PA, we used a model developed by Bjelke et al. (1991). Immunohistochemical techniques were carried out to determine the expression of neuronal and glial markers (NeuN and GFAP), eCBs/AEs synthesis and degradation enzymes (DAGLα, NAPE-PLD and FAAH) and their receptors (CB1 and PPARα). We found a decrease in NAPE-PLD and PPARα expression. Since NAPE-PLD and PPARα take part in the production and reception of biochemical actions of AEs, such as oleoylethanolamide, these results may suggest that PA plays a key role in the regulation of this system. These data agree with previous results obtained in the hippocampus and encourage us to develop further studies using AEs as potential neuroprotective compounds. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. 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.

  4. Fluvoxamine alters the activity of energy metabolism enzymes in the brain

    Directory of Open Access Journals (Sweden)

    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.

  5. Structure of glycerol-3-phosphate dehydrogenase, an essential monotopic membrane enzyme involved in respiration and metabolism

    International Nuclear Information System (INIS)

    Yeh, Joanne I.; Chinte, Unmesh; Du, Shoucheng

    2008-01-01

    Sn-glycerol-3-phosphate dehydrogenase (GlpD) is an essential membrane enzyme, functioning at the central junction of respiration, glycolysis, and phospholipid biosynthesis. Its critical role is indicated by the multitiered regulatory mechanisms that stringently controls its expression and function. Once expressed, GlpD activity is regulated through lipid-enzyme interactions in Escherichia coli. Here, we report seven previously undescribed structures of the fully active E. coli GlpD, up to 1.75 (angstrom) resolution. In addition to elucidating the structure of the native enzyme, we have determined the structures of GlpD complexed with substrate analogues phosphoenolpyruvate, glyceric acid 2-phosphate, glyceraldehyde-3-phosphate, and product, dihydroxyacetone phosphate. These structural results reveal conformational states of the enzyme, delineating the residues involved in substrate binding and catalysis at the glycerol-3-phosphate site. Two probable mechanisms for catalyzing the dehydrogenation of glycerol-3-phosphate are envisioned, based on the conformational states of the complexes. To further correlate catalytic dehydrogenation to respiration, we have additionally determined the structures of GlpD bound with ubiquinone analogues menadione and 2-n-heptyl-4-hydroxyquinoline N-oxide, identifying a hydrophobic plateau that is likely the ubiquinone-binding site. These structures illuminate probable mechanisms of catalysis and suggest how GlpD shuttles electrons into the respiratory pathway. Glycerol metabolism has been implicated in insulin signaling and perturbations in glycerol uptake and catabolism are linked to obesity in humans. Homologs of GlpD are found in practically all organisms, from prokaryotes to humans, with >45% consensus protein sequences, signifying that these structural results on the prokaryotic enzyme may be readily applied to the eukaryotic GlpD enzymes.

  6. Effect of Chromium(VI Toxicity on Enzymes of Nitrogen Metabolism in Clusterbean (Cyamopsis tetragonoloba L.

    Directory of Open Access Journals (Sweden)

    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.

  7. 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...

  8. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  10. Pharmacogenetic screening for polymorphisms in drug-metabolizing enzymes and drug transporters in a Dutch population.

    Science.gov (United States)

    Bosch, T M; Doodeman, V D; Smits, P H M; Meijerman, I; Schellens, J H M; Beijnen, J H

    2006-01-01

    A possible explanation for the wide interindividual variability in toxicity and efficacy of drug therapy is variation in genes encoding drug-metabolizing enzymes and drug transporters. The allelic frequency of these genetic variants, linkage disequilibrium (LD), and haplotype of these polymorphisms are important parameters in determining the genetic differences between patients. The aim of this study was to explore the frequencies of polymorphisms in drug-metabolizing enzymes (CYP1A1, CYP2C9, CYP2C19, CYP3A4, CYP2D6, CYP3A5, DPYD, UGT1A1, GSTM1, GSTP1, GSTT1) and drug transporters (ABCB1[MDR1] and ABCC2[MRP2]), and to investigate the LD and perform haplotype analysis of these polymorphisms in a Dutch population. Blood samples were obtained from 100 healthy volunteers and genomic DNA was isolated and amplified by PCR. The amplification products were sequenced and analyzed for the presence of polymorphisms by sequence alignment. In the study population, we identified 13 new single nucleotide polymorphisms (SNPs) in Caucasians and three new SNPs in non-Caucasians, in addition to previously recognized SNPs. Three of the new SNPs were found within exons, of which two resulted in amino acid changes (A428T in CYP2C9 resulting in the amino acid substitution D143V; and C4461T in ABCC2 in a non-Caucasian producing the amino acid change T1476M). Several LDs and haplotypes were found in the Caucasian individuals. In this Dutch population, the frequencies of 16 new SNPs and those of previously recognized SNPs were determined in genes coding for drug-metabolizing enzymes and drug transporters. Several LDs and haplotypes were also inferred. These data are important for further research to help explain the interindividual pharmacokinetic and pharmacodynamic variability in response to drug therapy.

  11. 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).

  12. 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.

  13. 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.

  14. 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

  15. Alternative Argets Within the Endocannabinoid System for Future Treatment of Gastrointestinal Diseases

    Directory of Open Access Journals (Sweden)

    Rudolf Schicho

    2011-01-01

    Full Text Available Many beneficial effects of herbal and synthetic cannabinoids on gut motility and inflammation have been demonstrated, suggesting a vast potential for these compounds in the treatment of gastrointestinal disorders. These effects are based on the so-called ‘endocannabinoid system’ (ECS, a cooperating network of molecules that regulate the metabolism of the body’s own and of exogenously administered cannabinoids. The ECS in the gastrointestinal tract quickly responds to homeostatic disturbances by de novo synthesis of its components to maintain homeostasis, thereby offering many potential targets for pharmacological intervention. Of major therapeutic interest are nonpsychoactive cannabinoids or compounds that do not directly target cannabinoid receptors but still possess cannabinoid-like properties. Drugs that inhibit endocannabinoid degradation and raise the level of endocannabinoids are becoming increasingly promising alternative therapeutic tools to manipulate the ECS.

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

    Science.gov (United States)

    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

  17. Endocannabinoids and Human Sperm Cells

    Directory of Open Access Journals (Sweden)

    Giovanna Zolese

    2010-10-01

    Full Text Available N-acylethanolamides (NAEs are naturally occurring signaling lipids consisting of amides and esters of long-chain polyunsaturated fatty acids. Usually they are present in a very small amounts in many mammalian tissues and cells, including human reproductive tracts and fluids. Recently, the presence of N-arachidonoylethanolamide (anandamide, AEA, the most characterised member of endocannabinoids, and its congeners palmitoylethanolamide (PEA and oleylethanolamide (OEA in seminal plasma, oviductal fluid, and follicular fluids was demonstrated. AEA has been shown to bind not only type-1 (CB1 and type-2 (CB2 cannabinoid receptors, but also type-1 vanilloid receptor (TRPV1, while PEA and OEA are inactive with respect to classical cannabinoid CB1 and CB2 but activate TRPV1 or peroxisome proliferator activate receptors (PPARs. This review concerns the most recent experimental data on PEA and OEA, endocannabinoid-like molecules which appear to exert their action exclusively on sperm cells with altered features, such as membrane characteristics and kinematic parameters. Their beneficial effects on these cells could suggest a possible pharmacological use of PEA and OEA on patients affected by some forms of idiopathic infertility.

  18. 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

  19. Angiotensin-converting enzyme inhibition improves cardiac fatty acid metabolism in patients with congestive heart failure.

    Science.gov (United States)

    Yamauchi, S; Takeishi, Y; Minamihaba, O; Arimoto, T; Hirono, O; Takahashi, H; Miyamoto, T; Nitobe, J; Nozaki, N; Tachibana, H; Watanabe, T; Fukui, A; Kubota, I

    2003-08-01

    This study aimed to examine whether angiotensin-converting enzyme (ACE) inhibition improved cardiac fatty acid metabolism in patients with congestive heart failure (CHF). Myocardial 123I-beta-methyl-iodophenylpentadecanoic acid (123I-BMIPP) imaging was performed in 25 patients with CHF and in 10 control subjects. Myocardial 123I-BMIPP images were obtained 30 min and 4 h after tracer injection. The heart-to-mediastinum (H/M) ratio of 123I-BMIPP uptake and the washout rate of 123I-BMIPP from the myocardium were calculated. Patients were given enalapril for 6 months, and 123I-BMIPP imaging was repeated. H/M ratios on early and delayed images were lower in CHF patients than in normal controls (Pacid metabolism by ACE inhibition may represent a new mechanism for the beneficial effect of this therapy in heart failure.

  20. Fluoxetine Facilitates Fear Extinction Through Amygdala Endocannabinoids

    Science.gov (United States)

    Gunduz-Cinar, Ozge; Flynn, Shaun; Brockway, Emma; Kaugars, Katherine; Baldi, Rita; Ramikie, Teniel S; Cinar, Resat; Kunos, George; Patel, Sachin; Holmes, Andrew

    2016-01-01

    Pharmacologically elevating brain endocannabinoids (eCBs) share anxiolytic and fear extinction-facilitating properties with classical therapeutics, including the selective serotonin reuptake inhibitor, fluoxetine. There are also known functional interactions between the eCB and serotonin systems and preliminary evidence that antidepressants cause alterations in brain eCBs. However, the potential role of eCBs in mediating the facilitatory effects of fluoxetine on fear extinction has not been established. Here, to test for a possible mechanistic contribution of eCBs to fluoxetine's proextinction effects, we integrated biochemical, electrophysiological, pharmacological, and behavioral techniques, using the extinction-impaired 129S1/Sv1mJ mouse strain. Chronic fluoxetine treatment produced a significant and selective increase in levels of anandamide in the BLA, and an associated decrease in activity of the anandamide-catabolizing enzyme, fatty acid amide hydrolase. Slice electrophysiological recordings showed that fluoxetine-induced increases in anandamide were associated with the amplification of eCB-mediated tonic constraint of inhibitory, but not excitatory, transmission in the BLA. Behaviorally, chronic fluoxetine facilitated extinction retrieval in a manner that was prevented by systemic or BLA-specific blockade of CB1 receptors. In contrast to fluoxetine, citalopram treatment did not increase BLA eCBs or facilitate extinction. Taken together, these findings reveal a novel, obligatory role for amygdala eCBs in the proextinction effects of a major pharmacotherapy for trauma- and stressor-related disorders and anxiety disorders. PMID:26514583

  1. Metabolism

    Science.gov (United States)

    ... lin), which signals cells to increase their anabolic activities. Metabolism is a complicated chemical process, so it's not ... how those enzymes or hormones work. When the metabolism of body chemicals is ... Hyperthyroidism (pronounced: hi-per-THIGH-roy-dih-zum). Hyperthyroidism ...

  2. Lack of evidence for metabolism of p-phenylenediamine by human hepatic cytochrome P450 enzymes

    International Nuclear Information System (INIS)

    Stanley, Lesley A.; Skare, Julie A.; Doyle, Edward; Powrie, Robert; D'Angelo, Diane; Elcombe, Clifford R.

    2005-01-01

    p-Phenylenediamine (PPD) is a widely used ingredient in permanent hair dyes; however, little has been published on its metabolism, especially with respect to hepatic cytochrome P450 (CYP)-mediated oxidation. This is regarded as a key step in the activation of carcinogenic arylamines that ultimately leads to the development of bladder cancer. Most epidemiology studies show no significant association between personal use of hair dyes and bladder cancer, but one recent study reported an increased risk of bladder cancer in women who were frequent users of permanent hair dyes. The aim of the present study was to use intact human hepatocytes, human liver microsomes, and heterologously expressed human CYPs to determine whether PPD is metabolised by hepatic CYPs to form an N-hydroxylamine. p-Phenylenediamine was N-acetylated by human hepatocytes to form N-acetylated metabolites, but there was no evidence for the formation of mono-oxygenated metabolites or for enzyme-mediated covalent binding of 14 C-PPD to microsomal protein. In contrast, 2-aminofluorene underwent CYP-mediated metabolism to ≥4 different hydroxylated metabolites. The lack of evidence for hepatic CYP-mediated metabolism of PPD is inconsistent with the hypothesis that this compound plays a causal role in the development of bladder cancer via a mode of action involving hepatic metabolism to an N-hydroxyarylamine

  3. [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.

  4. 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.

  5. 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.

  6. 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.)

  7. Role of endocannabinoids in regulating drug dependence

    Directory of Open Access Journals (Sweden)

    Daniela Parolaro

    2007-01-01

    Full Text Available Daniela Parolaro, Daniela Vigano’, Natalia Realini, Tiziana RubinoNeuroscience Center, DBSF, University of Insubria, Busto Arsizio, ItalyAbstract: This review will discuss the latest knowledge of how the endocannabinoid system might be involved in treating addiction to the most common illicit drugs. Experimental models are providing increasing evidence for the pharmacological management of endocannabinoid signaling not only to block the direct reinforcing effects of cannabis, opioids, nicotine and ethanol, but also for preventing relapse to the various drugs of abuse, including opioids, cocaine, nicotine, alcohol and metamphetamine. Preclinical and clinical studies suggest that the endocannabinoid system can be manipulated by the CB1 receptor antagonist SR141716A, that might constitute a new generation of compounds for treating addiction across different classes of abused drugs.Keywords: Endocannabinoids, drug dependence, opioids, nicotine, alcohol, psychostimulants

  8. Effects of sexually dimorphic growth hormone secretory patterns on arachidonic acid metabolizing enzymes in rodent heart

    International Nuclear Information System (INIS)

    Zhang, Furong; Yu, Xuming; He, Chunyan; Ouyang, Xiufang; Wu, Jinhua; Li, Jie; Zhang, Junjie; Duan, Xuejiao; Wan, Yu; Yue, Jiang

    2015-01-01

    The arachidonic acid (AA) metabolizing enzymes are the potential therapeutic targets of cardiovascular diseases (CVDs). As sex differences have been shown in the risk and outcome of CVDs, we investigated the regulation of heart AA metabolizing enzymes (COXs, LOXs, and CYPs) by sex-dependent growth hormone (GH) secretory patterns. The pulsatile (masculine) GH secretion at a physiological concentration decreased CYP1A1 and CYP2J3 mRNA levels more efficiently in the H9c2 cells compared with the constant (feminine) GH secretion; however, CYP1B1 mRNA levels were higher following the pulsatile GH secretion. Sex differences in CYP1A1, CYP1B1, and CYP2J11 mRNA levels were observed in both the wild-type and GHR deficient mice. No sex differences in the mRNA levels of COXs, LOXs, or CYP2E1 were observed in the wild-type mice. The constant GH infusion induced heart CYP1A1 and CYP2J11, and decreased CYP1B1 in the male C57/B6 mice constantly infused with GH (0.4 μg/h, 7 days). The activity of rat Cyp2j3 promoter was inhibited by the STAT5B protein, but was activated by C/EBPα (CEBPA). Compared with the constant GH administration, the levels of the nuclear phosphorylated STAT5B protein and its binding to the rat Cyp2j3 promoter were higher following the pulsatile GH administration. The constant GH infusion decreased the binding of the nuclear phosphorylated STAT5B protein to the mouse Cyp2j11 promoter. The data suggest the sexually dimorphic transcription of heart AA metabolizing enzymes, which might alter the risk and outcome of CVDs. GHR-STAT5B signal transduction pathway may be involved in the sex difference in heart CYP2J levels. - Highlights: • The transcription of heart Cyp1a1, Cyp1b1 and Cyp2j genes is sexually dimorphic. • There are no sex differences in the mRNA levels of heart COXs, LOXs, or CYP2E1. • GHR-STAT5B pathway is involved in sexually dimorphic transcription of heart Cpy2j genes. • Heart CYPs-mediated metabolism pathway of arachidonic acid may be sex

  9. Effects of sexually dimorphic growth hormone secretory patterns on arachidonic acid metabolizing enzymes in rodent heart

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Furong; Yu, Xuming [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); He, Chunyan [Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Ouyang, Xiufang; Wu, Jinhua; Li, Jie; Zhang, Junjie; Duan, Xuejiao [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Wan, Yu [Department of Physiology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China); Yue, Jiang, E-mail: yuejiang@whu.edu.cn [Department of Pharmacology, School of Basic Medical Sciences, Wuhan University, Wuhan 430071 (China)

    2015-12-15

    The arachidonic acid (AA) metabolizing enzymes are the potential therapeutic targets of cardiovascular diseases (CVDs). As sex differences have been shown in the risk and outcome of CVDs, we investigated the regulation of heart AA metabolizing enzymes (COXs, LOXs, and CYPs) by sex-dependent growth hormone (GH) secretory patterns. The pulsatile (masculine) GH secretion at a physiological concentration decreased CYP1A1 and CYP2J3 mRNA levels more efficiently in the H9c2 cells compared with the constant (feminine) GH secretion; however, CYP1B1 mRNA levels were higher following the pulsatile GH secretion. Sex differences in CYP1A1, CYP1B1, and CYP2J11 mRNA levels were observed in both the wild-type and GHR deficient mice. No sex differences in the mRNA levels of COXs, LOXs, or CYP2E1 were observed in the wild-type mice. The constant GH infusion induced heart CYP1A1 and CYP2J11, and decreased CYP1B1 in the male C57/B6 mice constantly infused with GH (0.4 μg/h, 7 days). The activity of rat Cyp2j3 promoter was inhibited by the STAT5B protein, but was activated by C/EBPα (CEBPA). Compared with the constant GH administration, the levels of the nuclear phosphorylated STAT5B protein and its binding to the rat Cyp2j3 promoter were higher following the pulsatile GH administration. The constant GH infusion decreased the binding of the nuclear phosphorylated STAT5B protein to the mouse Cyp2j11 promoter. The data suggest the sexually dimorphic transcription of heart AA metabolizing enzymes, which might alter the risk and outcome of CVDs. GHR-STAT5B signal transduction pathway may be involved in the sex difference in heart CYP2J levels. - Highlights: • The transcription of heart Cyp1a1, Cyp1b1 and Cyp2j genes is sexually dimorphic. • There are no sex differences in the mRNA levels of heart COXs, LOXs, or CYP2E1. • GHR-STAT5B pathway is involved in sexually dimorphic transcription of heart Cpy2j genes. • Heart CYPs-mediated metabolism pathway of arachidonic acid may be sex

  10. Carbohydrate Metabolism in Archaea: Current Insights into Unusual Enzymes and Pathways and Their Regulation

    Science.gov (United States)

    Esser, Dominik; Rauch, Bernadette

    2014-01-01

    SUMMARY The metabolism of Archaea, the third domain of life, resembles in its complexity those of Bacteria and lower Eukarya. However, this metabolic complexity in Archaea is accompanied by the absence of many “classical” pathways, particularly in central carbohydrate metabolism. Instead, Archaea are characterized by the presence of unique, modified variants of classical pathways such as the Embden-Meyerhof-Parnas (EMP) pathway and the Entner-Doudoroff (ED) pathway. The pentose phosphate pathway is only partly present (if at all), and pentose degradation also significantly differs from that known for bacterial model organisms. These modifications are accompanied by the invention of “new,” unusual enzymes which cause fundamental consequences for the underlying regulatory principles, and classical allosteric regulation sites well established in Bacteria and Eukarya are lost. The aim of this review is to present the current understanding of central carbohydrate metabolic pathways and their regulation in Archaea. In order to give an overview of their complexity, pathway modifications are discussed with respect to unusual archaeal biocatalysts, their structural and mechanistic characteristics, and their regulatory properties in comparison to their classic counterparts from Bacteria and Eukarya. Furthermore, an overview focusing on hexose metabolic, i.e., glycolytic as well as gluconeogenic, pathways identified in archaeal model organisms is given. Their energy gain is discussed, and new insights into different levels of regulation that have been observed so far, including the transcript and protein levels (e.g., gene regulation, known transcription regulators, and posttranslational modification via reversible protein phosphorylation), are presented. PMID:24600042

  11. The effect of enzymes upon metabolism, storage, and release of carbohydrates in normal and abnormal endometria.

    Science.gov (United States)

    Hughes, E C

    1976-07-01

    This paper presents preliminary data concerning the relationship of various components of glandular epithelium and effect of enzymes on metabolism, storage, and release of certain substances in normal and abnormal endometria. Activity of these endometrial enzymes has been compared between two groups: 252 patients with normal menstrual histories and 156 patients, all over the age of 40, with abnormal uterine bleeding. Material was obtained by endometrial biopsy or curettage. In the pathologic classification of the group of 156, 30 patients had secretory endometria, 88 patients had endometria classified as proliferative, 24 were classified as endometrial hyperplasia, and 14 were classified as adenocarcinoma. All tissue was studied by histologic, histochemical, and biochemical methods. Glycogen synthetase activity caused synthesis of glucose to glycogen, increasing in amount until midcycle, when glycogen phosphorylase activity caused the breakdown to glucose during the regressive stage of endometrial activity. This normal cyclic activity did not occur in the abnormal endometria, where activity of both enzymes continued at low constant tempo. Only the I form of glycogen synthetase increased as the tissue became more hyperplastic. With the constant glycogen content and the increased activity of both the TPN isocitric dehydrogenase and glucose-6-phosphate dehydrogenase in the hyperplastic and cancerous endometria, tissue energy was created, resulting in abnormal cell proliferation. These altered biochemical and cellular activities may be the basis for malignant cell growth.

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

    Science.gov (United States)

    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

  13. Tributyltin toxicity in abalone (Haliotis diversicolor supertexta) assessed by antioxidant enzyme activity, metabolic response, and histopathology.

    Science.gov (United States)

    Zhou, Jin; Zhu, Xiao-shan; Cai, Zhong-hua

    2010-11-15

    A toxicity test was performed to investigate the possible harmful effects of tributyltin (TBT) on abalone (Haliotis diversicolor supertexta). Animals were exposed to TBT in a range of environmentally relevant concentrations (2, 10 and 50 ng/L) for 30 days under laboratory conditions. TBT-free conditions were used as control treatments. The activity of antioxidant enzymes superoxide dismutase (SOD) and peroxidase (POD), and malondialdehyde (MDA), along with levels of haemolymph metabolites, and hepatopancreas histopathology were analyzed. The results showed that TBT decreased SOD activity, and increased POD level and MDA production in a dose-dependent way, indicating that oxidative injury was induced by TBT. Haemolymph metabolite measurements showed that TBT increased alanine and glutamate levels, and decreased glucose content, which suggested perturbation of energy metabolism. Elevated levels of acetate and pyruvate in the haemolymph indicated partial alteration of lipid metabolism. A decrease in lactate and an increase in succinate, an intermediate of the tricarboxylic acid (TCA) cycle, indicated disturbance of amino acid metabolism. Hepatopancreas tissues also exhibited inflammatory responses characterized by histopathological changes such as cell swelling, granular degeneration, and inflammation. Taken together, these results demonstrated that TBT was a potential toxin with a variety of deleterious effects on abalone. Copyright © 2010 Elsevier B.V. All rights reserved.

  14. Endocannabinoids and cardiovascular prevention: real progress?

    Directory of Open Access Journals (Sweden)

    Livio Dei Cas

    2009-08-01

    Full Text Available ABSTRACT: The prevalence of obesity continues to increase and represents one of the principal causes of cardiovascular morbidity and mortality. After the discovery of a specific receptor of the psychoactive principle of marijuana, the cannabinoid receptors and their endogenous ligands, several studies have demonstrated the role of this system in the control of food intake and energy balance and its overactivity in obesity. Recent studies with the CB1 receptor antagonist rimonabant have demonstrated favorable effects such as a reduction in body weight and waist circumference and an improvement in metabolic factors (cholesterol, triglycerides, glycemia etc. Therefore, the antagonism of the endocannabinoid (EC system, if recent data can be confirmed, could be a new treatment target for high risk overweight or obese patients. Obesity is a growing problem that has epidemic proportions worldwide and is associated with an increased risk of premature death (1-3. Individuals with a central deposition of fats have elevated cardiovascular morbidity and mortality (including stroke, heart failure and myocardial infarction and, because of a growing prevalence not only in adults but also in adolescents, it was reclassified in AHA guidelines as a “major modifiable risk factor” for coronary heart disease (4, 5. Although first choice therapy in obesity is based on correcting lifestyle (diet and physical activity in patients with abdominal obesity and high cardiovascular risk and diabetes, often it is necessary to use drugs which reduce the risks. The EC system represents a new target for weight control and the improvement of lipid and glycemic metabolism (6, 7. (Heart International 2007; 3: 27-34

  15. Iron Sulfur and Molybdenum Cofactor Enzymes Regulate the Drosophila Life Cycle by Controlling Cell Metabolism

    Science.gov (United States)

    Marelja, Zvonimir; Leimkühler, Silke; Missirlis, Fanis

    2018-01-01

    Iron sulfur (Fe-S) clusters and the molybdenum cofactor (Moco) are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i) mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii) increased iron transiently displaces manganese on superoxide dismutase, which

  16. Iron Sulfur and Molybdenum Cofactor Enzymes Regulate the Drosophila Life Cycle by Controlling Cell Metabolism

    Directory of Open Access Journals (Sweden)

    Zvonimir Marelja

    2018-02-01

    Full Text Available Iron sulfur (Fe-S clusters and the molybdenum cofactor (Moco are present at enzyme sites, where the active metal facilitates electron transfer. Such enzyme systems are soluble in the mitochondrial matrix, cytosol and nucleus, or embedded in the inner mitochondrial membrane, but virtually absent from the cell secretory pathway. They are of ancient evolutionary origin supporting respiration, DNA replication, transcription, translation, the biosynthesis of steroids, heme, catabolism of purines, hydroxylation of xenobiotics, and cellular sulfur metabolism. Here, Fe-S cluster and Moco biosynthesis in Drosophila melanogaster is reviewed and the multiple biochemical and physiological functions of known Fe-S and Moco enzymes are described. We show that RNA interference of Mocs3 disrupts Moco biosynthesis and the circadian clock. Fe-S-dependent mitochondrial respiration is discussed in the context of germ line and somatic development, stem cell differentiation and aging. The subcellular compartmentalization of the Fe-S and Moco assembly machinery components and their connections to iron sensing mechanisms and intermediary metabolism are emphasized. A biochemically active Fe-S core complex of heterologously expressed fly Nfs1, Isd11, IscU, and human frataxin is presented. Based on the recent demonstration that copper displaces the Fe-S cluster of yeast and human ferredoxin, an explanation for why high dietary copper leads to cytoplasmic iron deficiency in flies is proposed. Another proposal that exosomes contribute to the transport of xanthine dehydrogenase from peripheral tissues to the eye pigment cells is put forward, where the Vps16a subunit of the HOPS complex may have a specialized role in concentrating this enzyme within pigment granules. Finally, we formulate a hypothesis that (i mitochondrial superoxide mobilizes iron from the Fe-S clusters in aconitase and succinate dehydrogenase; (ii increased iron transiently displaces manganese on superoxide

  17. 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.

  18. Enzyme and metabolic engineering for the production of novel biopolymers: crossover of biological and chemical processes.

    Science.gov (United States)

    Matsumoto, Ken'ichiro; Taguchi, Seiichi

    2013-12-01

    The development of synthetic biology has transformed microbes into useful factories for producing valuable polymers and/or their precursors from renewable biomass. Recent progress at the interface of chemistry and biology has enabled the production of a variety of new biopolymers with properties that substantially differ from their petroleum-derived counterparts. This review touches on recent trials and achievements in the field of biopolymer synthesis, including chemo-enzymatically synthesized aliphatic polyesters, wholly biosynthesized lactate-based polyesters, polyhydroxyalkanoates and other unusual bacterially synthesized polyesters. The expanding diversities in structure and the material properties of biopolymers are key for exploring practical applications. The enzyme and metabolic engineering approaches toward this goal are discussed by shedding light on the successful case studies. Copyright © 2013 Elsevier Ltd. All rights reserved.

  19. Genetic manipulation of a metabolic enzyme and a transcriptional regulator increasing succinate excretion from unicellular cyanobacterium

    Directory of Open Access Journals (Sweden)

    Takashi eOsanai

    2015-10-01

    Full Text Available Succinate is a building block compound that the U.S. Department of Energy has declared as important in biorefineries, and it is widely used as a commodity chemical. Here, we identified the two genes increasing succinate production of the unicellular cyanobacterium Synechocystis sp. PCC 6803. Succinate was excreted under dark, anaerobic conditions, and its production level increased by knocking out ackA, which encodes an acetate kinase, and by overexpressing sigE, which encodes an RNA polymerase sigma factor. Glycogen catabolism and organic acid biosynthesis were enhanced in the mutant lacking ackA and overexpressing sigE, leading to an increase in succinate production reaching 5 times of the wild-type levels. Our genetic and metabolomic analyses thus demonstrated the effect of genetic manipulation of a metabolic enzyme and a transcriptional regulator on succinate excretion from this cyanobacterium with the data based on metabolomic technique.

  20. Gene expression variability in human hepatic drug metabolizing enzymes and transporters.

    Directory of Open Access Journals (Sweden)

    Lun Yang

    Full Text Available Interindividual variability in the expression of drug-metabolizing enzymes and transporters (DMETs in human liver may contribute to interindividual differences in drug efficacy and adverse reactions. Published studies that analyzed variability in the expression of DMET genes were limited by sample sizes and the number of genes profiled. We systematically analyzed the expression of 374 DMETs from a microarray data set consisting of gene expression profiles derived from 427 human liver samples. The standard deviation of interindividual expression for DMET genes was much higher than that for non-DMET genes. The 20 DMET genes with the largest variability in the expression provided examples of the interindividual variation. Gene expression data were also analyzed using network analysis methods, which delineates the similarities of biological functionalities and regulation mechanisms for these highly variable DMET genes. Expression variability of human hepatic DMET genes may affect drug-gene interactions and disease susceptibility, with concomitant clinical implications.

  1. Modeling the role of covalent enzyme modification in Escherichia coli nitrogen metabolism

    International Nuclear Information System (INIS)

    Kidd, Philip B; Wingreen, Ned S

    2010-01-01

    In the bacterium Escherichia coli, the enzyme glutamine synthetase (GS) converts ammonium into the amino acid glutamine. GS is principally active when the cell is experiencing nitrogen limitation, and its activity is regulated by a bicyclic covalent modification cascade. The advantages of this bicyclic-cascade architecture are poorly understood. We analyze a simple model of the GS cascade in comparison to other regulatory schemes and conclude that the bicyclic cascade is suboptimal for maintaining metabolic homeostasis of the free glutamine pool. Instead, we argue that the lag inherent in the covalent modification of GS slows the response to an ammonium shock and thereby allows GS to transiently detoxify the cell, while maintaining homeostasis over longer times

  2. Expression changes of hippocampal energy metabolism enzymes contribute to behavioural abnormalities during chronic morphine treatment

    Institute of Scientific and Technical Information of China (English)

    Xiao-Lan Chen; Jing-Gen Liu; Gang Lu; Ying-Xia Gong; Liang-Cai Zhao; Jie Chen; Zhi-Qiang Chi; Yi-Ming Yang; Zhong Chen; Qing-lin Li

    2007-01-01

    Dependence and impairment of learning and memory are two well-established features caused by abused drugs such as opioids. The hippocampus is an important region associated with both drug dependence and learning and memory. However, the molecular events in hippocampus following exposure to abused drugs such as opioids are not well understood. Here we examined the effect of chronic morphine treatment on hippocampal protein expression by proteomic analyses. We found that chronic exposure of mice to morphine for 10 days produced robust morphine withdrawal jumping and memory impairment, and also resulted in a significant downregulation of hippocampal protein levels of three metabolic enzymes, including Fe-S protein 1 of NADH dehydrogenase, dihydrolipoamide acetyltransferase or E2 component of the pyruvate dehydrogenase complex and lactate dehydrogenase 2. Further real-time quantitative PCR analyses confirmed that the levels of the corresponding mRNAs were also remarkably reduced. Consistent with these findings, lower ATP levels and an impaired ability to convert glucose into ATP were also observed in the hippocampus of chronically treated mice. Opioid antagonist naltrexone administrated concomitantly with morphine significantly suppressed morphine withdrawal jumping and reversed the downregulation of these proteins. Acute exposure to morphine also produced robust morphine withdrawal jumping and significant memory impairment, but failed to decrease the expression of these three proteins. Intrahippocampal injection of D-glucose before morphine administration significantly enhanced ATP levels and suppressed morphine withdrawal jumping and memory impairment in acute morphine-treated but not in chronic morphine-treated mice. Intraperitoneal injection of high dose of D-glucose shows a similar effect on morphine-induced withdrawal jumping as the central treatment. Taken together, our results suggest that reduced expression of the three metabolic enzymes in the hippocampus as

  3. Effects of triiodothyronine on turnover rate and metabolizing enzymes for thyroxine in thyroidectomized rats.

    Science.gov (United States)

    Nagao, Hidenori; Sasaki, Makoto; Imazu, Tetsuya; Takahashi, Kenjo; Aoki, Hironori; Minato, Kouichi

    2014-10-29

    Previous studies in rats have indicated that surgical thyroidectomy represses turnover of serum thyroxine (T4). However, the mechanism of this process has not been identified. To clarify the mechanism, we studied adaptive variation of metabolic enzymes involved in T4 turnover. We compared serum T4 turnover rates in thyroidectomized (Tx) rats with or without infusion of active thyroid hormone, triiodothyronine (T3). Furthermore, the levels of mRNA expression and activity of the metabolizing enzymes, deiodinase type 1 (D1), type 2 (D2), uridine diphosphate-glucuronosyltransferase (UGT), and sulfotransferase were also compared in several tissues with or without T3 infusion. After the T3 infusion, the turnover rate of serum T4 in Tx rats returned to normal. Although mRNA expression and activity of D1 decreased significantly in both liver and kidneys without T3 infusion, D2 expression and activity increased markedly in the brain, brown adipose tissue, and skeletal muscle. Surprisingly, hepatic UGT mRNA expression and activity in Tx rats increased significantly in comparison with normal rats, and returned to normal after T3 infusion. This study suggests that repression of the disappearance of serum T4 in rats after Tx is a homeostatic response to decreased serum T3 concentrations. Additionally, T4 glucuronide is a storage form of T4, but may also have biological significance. These results suggest strongly that repression of deiodination of T4 by D1 in the liver and kidneys plays a major role in thyroid hormone homeostasis in Tx rats, and that hepatic UGT also plays a key role in this mechanism. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Dynamics of sugar-metabolic enzymes and sugars accumulation during watermelon (citrullus lanatus) fruit development

    International Nuclear Information System (INIS)

    Zhang, H.

    2016-01-01

    We analyzed sugar accumulation and the activities of sugar-metabolic enzymes in ripening fruits of three cultivars of watermelon; a high-sugar type w2, a low-sugar type (w1), and their hybrid. In w2, the glucose and fructose contents were higher than the sucrose content in the earlier stage of fruit development, and fruit growth was accompanied by increases in glucose, fructose, and sucrose contents. The sucrose content increased substantially after 20 days after anthesis (DAA) and it was the main soluble sugar in mature fruit (sucrose: hexoses ratio, 0.71). In W, the fructose and glucose contents were significantly higher than the sucrose content in mature fruit (sucrose: hexoses ratio, 0.25). Comparing the two parent cultivars, sucrose was the most important factor affecting the total sugar content in mature fruit, although glucose and fructose also contributed to total sugar contents. The fructose and glucose contents in the fruit of F1 were mid-way between those of their parents, while the sucrose content was closer to that of W (sucrose:hexoses ratio in F1, 0.26). In the early stage of fruit development of W2, the activities of acid invertase and neutral invertase were higher than those of sucrose synthase and sucrose phosphate synthase. After 20 DAA, the acid invertase and neutral invertase activities decreased and those of sucrose synthase and sucrose phosphate synthase increased, leading to increased sucrose content. In W1, the activities of acid invertase and neutral invertase were higher than those of sucrose synthase and sucrose phosphate synthase at the early stage. The sucrose synthase and sucrose phosphate synthase activities were lower in W1 than in W2 at the later stages of fruit development. The patterns of sugar accumulation and sugar-metabolic enzyme activities during fruit development in F1 were similar to those in W1. (author)

  5. 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...

  6. Interplay Between n-3 and n-6 Long-Chain Polyunsaturated Fatty Acids and the Endocannabinoid System in Brain Protection and Repair.

    Science.gov (United States)

    Dyall, Simon C

    2017-11-01

    The brain is enriched in arachidonic acid (ARA) and docosahexaenoic acid (DHA), long-chain polyunsaturated fatty acids (LCPUFAs) of the n-6 and n-3 series, respectively. Both are essential for optimal brain development and function. Dietary enrichment with DHA and other long-chain n-3 PUFA, such as eicosapentaenoic acid (EPA), has shown beneficial effects on learning and memory, neuroinflammatory processes, and synaptic plasticity and neurogenesis. ARA, DHA and EPA are precursors to a diverse repertoire of bioactive lipid mediators, including endocannabinoids. The endocannabinoid system comprises cannabinoid receptors, their endogenous ligands, the endocannabinoids, and their biosynthetic and degradation enzymes. Anandamide (AEA) and 2-arachidonoylglycerol (2-AG) are the most widely studied endocannabinoids and are both derived from phospholipid-bound ARA. The endocannabinoid system also has well-established roles in neuroinflammation, synaptic plasticity and neurogenesis, suggesting an overlap in the neuroprotective effects observed with these different classes of lipids. Indeed, growing evidence suggests a complex interplay between n-3 and n-6 LCPUFA and the endocannabinoid system. For example, long-term DHA and EPA supplementation reduces AEA and 2-AG levels, with reciprocal increases in levels of the analogous endocannabinoid-like DHA and EPA-derived molecules. This review summarises current evidence of this interplay and discusses the therapeutic potential for brain protection and repair.

  7. The Endocannabinoid System across Postnatal Development in Transmembrane Domain Neuregulin 1 Mutant Mice

    Directory of Open Access Journals (Sweden)

    Rose Chesworth

    2018-02-01

    Full Text Available The use of cannabis is a well-established component risk factor for schizophrenia, particularly in adolescent individuals with genetic predisposition for the disorder. Alterations to the endocannabinoid system have been found in the prefrontal cortex of patients with schizophrenia. Thus, we assessed whether molecular alterations exist in the endocannabinoid signalling pathway during brain development in a mouse model for the schizophrenia risk gene neuregulin 1 (Nrg1. We analysed transcripts encoding key molecules of the endocannabinoid system in heterozygous transmembrane domain Nrg1 mutant mice (Nrg1 TM HET, which is known to have increased sensitivity to cannabis exposure. Tissue from the prelimbic cortex and hippocampus of male and female Nrg1 TM HET mice and wild type-like littermates was collected at postnatal days (PNDs 7, 10, 14, 21, 28, 35, 49, and 161. Quantitative polymerase chain reaction was conducted to assess mRNA levels of cannabinoid receptor 1 (CB1R and enzymes for the synthesis and breakdown of the endocannabinoid 2-arachidonoylglycerol [i.e., diacylglycerol lipase alpha (DAGLα, monoglyceride lipase (MGLL, and α/β-hydrolase domain-containing 6 (ABHD6]. No sex differences were found for any transcripts in either brain region; thus, male and female data were pooled. Hippocampal and cortical mRNA expression of DAGLα, MGLL, and ABHD6 increased until PND 21–35 and then decreased and stabilised for the rest of postnatal development. Hippocampal CB1R mRNA expression increased until PND 21 and decreased after this age. Expression levels of these endocannabinoid markers did not differ in Nrg1 TM HET compared to control mice at any time point. Here, we demonstrate dynamic changes in the developmental trajectory of several key endocannabinoid system transcripts in the mouse brain, which may correspond with periods of endocannabinoid system maturation. Nrg1 TM HET mutation did not alter the developmental trajectory of the

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

    Science.gov (United States)

    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.

  9. 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.

  10. Polymorphisms in drug-metabolizing enzymes: What is their clinical relevance and why do they exist?

    Energy Technology Data Exchange (ETDEWEB)

    Nebert, D.W. [Univ. of Cincinnati Medical Center, OH (United States)

    1997-02-01

    The beautiful report by Sachse in this issue of the journal represents the culmination of 2 decades of increasingly exciting work on the {open_quotes}debrisoquine oxidation polymorphism,{close_quotes} one of dozens of pharmacogenetic or ecogenetic polymorphisms that have been shown to have an important impact on innumerable clinical diseases. Pharmacogenetics is the study of the hereditary basis of the differences in responses to drugs. Ecogenetics is the broader field of interindividual differences in response to all environmental chemical and physical agents (e.g., heavy metals, insecticides, compounds formed during combustion, and UV radiation). It is now clear that each of us has his or her own {open_quotes}individual fingerprint{close_quotes} of unique alleles encoding the so-called drug-metabolizing enzymes (DMEs) and the receptors that regulate these enzymes. In this invited editorial, I first introduce the current thinking in the field of DME (and DME-receptor) research and how DMEs have evolved from animal-plant interactions. I then describe the debrisoquine oxidation polymorphism, as well as two other relevant DME polymorphisms; show the relationship between these polymorphisms and human disease; provide examples of synergistic effects caused by the combination of two DME polymorphisms; and discuss the ethical considerations of such research. Last, I speculate on why these allelic frequencies of the DME genes might exist in human populations in the first place. 35 refs.

  11. Molecular, cellular, and tissue impact of depleted uranium on xenobiotic-metabolizing enzymes.

    Science.gov (United States)

    Gueguen, Yann; Rouas, Caroline; Monin, Audrey; Manens, Line; Stefani, Johanna; Delissen, Olivia; Grison, Stéphane; Dublineau, Isabelle

    2014-02-01

    Enzymes that metabolize xenobiotics (XME) are well recognized in experimental models as representative indicators of organ detoxification functions and of exposure to toxicants. As several in vivo studies have shown, uranium can alter XME in the rat liver or kidneys after either acute or chronic exposure. To determine how length or level of exposure affects these changes in XME, we continued our investigation of chronic rat exposure to depleted uranium (DU, uranyl nitrate). The first study examined the effect of duration (1-18 months) of chronic exposure to DU, the second evaluated dose dependence, from a level close to that found in the environment near mining sites (0.2 mg/L) to a supra-environmental dose (120 mg/L, 10 times the highest level naturally found in the environment), and the third was an in vitro assessment of whether DU exposure directly affects XME and, in particular, CYP3A. The experimental in vivo models used here demonstrated that CYP3A is the enzyme modified to the greatest extent: high gene expression changed after 6 and 9 months. The most substantial effects were observed in the liver of rats after 9 months of exposure to 120 mg/L of DU: CYP3A gene and protein expression and enzyme activity all decreased by more than 40 %. Nonetheless, no direct effect of DU by itself was observed after in vitro exposure of rat microsomal preparations, HepG2 cells, or human primary hepatocytes. Overall, these results probably indicate the occurrence of regulatory or adaptive mechanisms that could explain the indirect effect observed in vivo after chronic exposure.

  12. Photoperiodism and enzyme rhythms: Kinetic characteristics of the photoperiodic induction of Crassulacean acid metabolism.

    Science.gov (United States)

    Brulfert, J; Guerrier, D; Queiroz, O

    1975-01-01

    The effect of photoperiod on Crassulacean acid metabolism (CAM) in Kalanchoe blossfeldiana Poellniz, cv. Tom Thumb, has characteristics similar to its effect on flowering in this plant (although these two phenomena are not causally related). The photoperiodic control of CAM is based on (a) dependance on phytochrome, (b) an endogenous circadian rhythm of sensitivity to photoperiodic signals, (c) a balance between specific positive (increase in enzyme capacity) and negative (inhibitory substances) effects of the photoperiod. Variations in malate content, capacity of phosphoenolpyruvate (PEP) carboxylase, and capacity of CAM inhibitors in young leaves were measured under photoperiodic conditions noninductive for CAM and after transfer into photoperiodic conditions inductive for CAM. Essential characteristics of the photoperiodic induction of CAM are: 1) lag time for malate accumulation; 2) after-effect of the inductive photoperiod on the malate accumulation, on the increase in PEP carboxylase capacity, and on the decrease in the level of long-day produced inhibitors; final levels of malate, enzyme capacity and inhibitor are proportional to the number of inductive day-night cycles; 3) cireadian rhythm in PEP carboxylase capacity with a fixed phase under noninductive photoperiods and a continuously shifting phase under inductive photoperiods, after complex advancing and delaying transients. Kinetic similarities indicate that photoperiodic control of different physiological functions, namely, CAM and flowering, may be achieved through similar mechanisms. Preliminary results with species of Bryophyllum and Sedum support this hypothesis. Phase relationships suggest different degrees of coupling between endogenous enzymic rhythm and photoperiod, depending on whether the plants are under long days or short days.

  13. Endocannabinoid involvement in reward and impulsivity in addiction

    NARCIS (Netherlands)

    van Hell, H.H.

    2011-01-01

    Addiction is one of the most disabling diseases in the world. An important neurotransmitter system that has recently been implicated in addiction is the endocannabinoid system. The endocannabinoid system consists of cannabinoid receptors and endocannabinoid ligands that work on these receptors.

  14. 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.

  15. Alteration of Fatty-Acid-Metabolizing Enzymes Affects Mitochondrial Form and Function in Hereditary Spastic Paraplegia

    Science.gov (United States)

    Tesson, Christelle; Nawara, Magdalena; Salih, Mustafa A.M.; Rossignol, Rodrigue; Zaki, Maha S.; Al Balwi, Mohammed; Schule, Rebecca; Mignot, Cyril; Obre, Emilie; Bouhouche, Ahmed; Santorelli, Filippo M.; Durand, Christelle M.; Oteyza, Andrés Caballero; El-Hachimi, Khalid H.; Al Drees, Abdulmajeed; Bouslam, Naima; Lamari, Foudil; Elmalik, Salah A.; Kabiraj, Mohammad M.; Seidahmed, Mohammed Z.; Esteves, Typhaine; Gaussen, Marion; Monin, Marie-Lorraine; Gyapay, Gabor; Lechner, Doris; Gonzalez, Michael; Depienne, Christel; Mochel, Fanny; Lavie, Julie; Schols, Ludger; Lacombe, Didier; Yahyaoui, Mohamed; Al Abdulkareem, Ibrahim; Zuchner, Stephan; Yamashita, Atsushi; Benomar, Ali; Goizet, Cyril; Durr, Alexandra; Gleeson, Joseph G.; Darios, Frederic; Brice, Alexis; Stevanin, Giovanni

    2012-01-01

    Hereditary spastic paraplegia (HSP) is considered one of the most heterogeneous groups of neurological disorders, both clinically and genetically. The disease comprises pure and complex forms that clinically include slowly progressive lower-limb spasticity resulting from degeneration of the corticospinal tract. At least 48 loci accounting for these diseases have been mapped to date, and mutations have been identified in 22 genes, most of which play a role in intracellular trafficking. Here, we identified mutations in two functionally related genes (DDHD1 and CYP2U1) in individuals with autosomal-recessive forms of HSP by using either the classical positional cloning or a combination of whole-genome linkage mapping and next-generation sequencing. Interestingly, three subjects with CYP2U1 mutations presented with a thin corpus callosum, white-matter abnormalities, and/or calcification of the basal ganglia. These genes code for two enzymes involved in fatty-acid metabolism, and we have demonstrated in human cells that the HSP pathophysiology includes alteration of mitochondrial architecture and bioenergetics with increased oxidative stress. Our combined results focus attention on lipid metabolism as a critical HSP pathway with a deleterious impact on mitochondrial bioenergetic function. PMID:23176821

  16. A Bayesian method for identifying missing enzymes in predicted metabolic pathway databases

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    Karp Peter D

    2004-06-01

    Full Text Available Abstract Background The PathoLogic program constructs Pathway/Genome databases by using a genome's annotation to predict the set of metabolic pathways present in an organism. PathoLogic determines the set of reactions composing those pathways from the enzymes annotated in the organism's genome. Most annotation efforts fail to assign function to 40–60% of sequences. In addition, large numbers of sequences may have non-specific annotations (e.g., thiolase family protein. Pathway holes occur when a genome appears to lack the enzymes needed to catalyze reactions in a pathway. If a protein has not been assigned a specific function during the annotation process, any reaction catalyzed by that protein will appear as a missing enzyme or pathway hole in a Pathway/Genome database. Results We have developed a method that efficiently combines homology and pathway-based evidence to identify candidates for filling pathway holes in Pathway/Genome databases. Our program not only identifies potential candidate sequences for pathway holes, but combines data from multiple, heterogeneous sources to assess the likelihood that a candidate has the required function. Our algorithm emulates the manual sequence annotation process, considering not only evidence from homology searches, but also considering evidence from genomic context (i.e., is the gene part of an operon? and functional context (e.g., are there functionally-related genes nearby in the genome? to determine the posterior belief that a candidate has the required function. The method can be applied across an entire metabolic pathway network and is generally applicable to any pathway database. The program uses a set of sequences encoding the required activity in other genomes to identify candidate proteins in the genome of interest, and then evaluates each candidate by using a simple Bayes classifier to determine the probability that the candidate has the desired function. We achieved 71% precision at a

  17. 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

  18. [L-arginine metabolism enzyme activities in rat liver subcellular fractions under condition of protein deprivation].

    Science.gov (United States)

    Kopyl'chuk, G P; Buchkovskaia, I M

    2014-01-01

    The features of arginase and NO-synthase pathways of arginine's metabolism have been studied in rat liver subcellular fractions under condition of protein deprivation. During the experimental period (28 days) albino male rats were kept on semi synthetic casein diet AIN-93. The protein deprivation conditions were designed as total absence of protein in the diet and consumption of the diet partially deprived with 1/2 of the casein amount compared to in the regular diet. Daily diet consumption was regulated according to the pair feeding approach. It has been shown that the changes of enzyme activities, involved in L-arginine metabolism, were characterized by 1.4-1.7 fold decrease in arginase activity, accompanied with unchanged NO-synthase activity in cytosol. In mitochondrial fraction the unchanged arginase activity was accompanied by 3-5 fold increase of NO-synthase activity. At the terminal stages of the experiment the monodirectional dynamics in the studied activities have been observed in the mitochondrial and cytosolfractions in both experimental groups. In the studied subcellular fractions arginase activity decreased (2.4-2.7 fold with no protein in the diet and 1.5 fold with partly supplied protein) and was accompanied by NO-synthase activity increase by 3.8 fold in cytosole fraction, by 7.2 fold in mitochondrial fraction in the group with no protein in the diet and by 2.2 and 3.5 fold in the group partialy supplied with protein respectively. The observed tendency is presumably caused by the switch of L-arginine metabolism from arginase into oxidizing NO-synthase parthway.

  19. The endocannabinoid system: a new pharmacological target for obesity treatment?

    Science.gov (United States)

    Hu, Jia; Zhu, Chao; Huang, Mao

    2009-06-01

    Being a great threaten for human health, obesity has become a pandemic chronic disease. There have been several therapeutic treatments for this social health issue, including diet and exercise therapy, medication and surgery, among which the diet is still the most common way. However, none of these therapeutic measures available is ideal, making it necessary to find an effective medical treatment. The endocannabinoid system, which is well known for its contributions in certain mental processes such as relaxation, amelioration of pain and anxiety, and sedation initiation, has been recently reported to play an essential role in regulating appetite and metabolism to maintain energy balance, leading to the belief that endocannabinoid system is closely related to obesity. This new discovery deepens our understanding of obesity, and provides us with a new direction for clinical obesity treatment. Rimonabant is an antagonist for CB1, and has entered the market in some countries. However, although effective as an anti-obesity drug, rimonabant also causes obviously adverse side-effects, thus is being doubted and denied for medical usage.

  20. Modulation of Xenobiotic Metabolizing Enzyme and Transporter Gene Expression in Primary Cultures of Human Hepatocytes by ToxCast Chemicals

    Science.gov (United States)

    ToxCast chemicals were assessed for induction or suppression of xenobiotic metabolizing enzyme and transporter gene expression using primary human hepatocytes. The mRNA levels of 14 target and 2 control genes were measured: ABCB1, ABCB11, ABCG2, SLCO1B1, CYP1A1, CYP1A2, CYP2B6, C...

  1. 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

  2. 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

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  6. 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.

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

    Science.gov (United States)

    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.

  8. [Effects of waterlogging on the growth and energy-metabolic enzyme activities of different tree species].

    Science.gov (United States)

    Wang, Gui-Bin; Cao, Fu-Liang; Zhang, Xiao-Yan; Zhang, Wang-Xiang

    2010-03-01

    Aimed to understand the waterlogging tolerance and adaptation mechanisms of different tree species, a simulated field experiment was conducted to study the growth and energy-metabolic enzyme activities of one-year-old seedlings of Taxodium distichum, Carya illinoensis, and Sapium sebiferum. Three treatments were installed, i. e., CK, waterlogging, and flooding, with the treatment duration being 60 days. Under waterlogging and flooding, the relative growth of test tree species was in the order of T. distichum > C. illinoensis > S. sebiferum, indicating that T. distichum had the strongest tolerance against waterlogging and flooding, while S. sebiferum had the weakest one. Also under waterlogging and flooding, the root/crown ratio of the three tree species increased significantly, suggesting that more photosynthates were allocated in roots, and the lactate dehydrogenase (LDH) and alcohol dehydrogenase (ADH) activities of the tree species also had a significant increase. Among the test tree species, T. distichum had the lowest increment of LDH and ADH activities under waterlogging and flooding, but the increment could maintain at a higher level in the treatment duration, while for C. illinoensis and S. sebiferum, the increment was larger during the initial and medium period, but declined rapidly during the later period of treatment. The malate dehydrogenase (MDH), phosphohexose (HPI), and glucose-6-phosphate dehydrogenase (G6PDH) -6-phosphogluconate dehydrogenase (6PGDH) activities of the tree species under waterlogging and flooding had a significant decrease, and the decrement was the largest for T. distichum, being 35.6% for MDH, 21.0% for HPI, and 22.7% for G6PDH - 6PGDH under flooding. It was suggested that under waterlogging and flooding, the tree species with strong waterlogging tolerance had a higher ability to maintain energy-metabolic balance, and thus, its growth could be maintained at a certain level.

  9. 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.

  10. Metabolic Syndrome and Serum Liver Enzymes Level at Patients with Type 2 Diabetes Mellitus

    Science.gov (United States)

    Music, Miralem; Dervisevic, Amela; Pepic, Esad; Lepara, Orhan; Fajkic, Almir; Ascic-Buturovic, Belma; Tuna, Enes

    2015-01-01

    Objectives: The aim of this study was to evaluate liver function in patients with type 2 diabetes mellitus (T2DM) with and without metabolic syndrome (MS) by determining serum levels of gamma glutamyltransferase (GGT), alanine aminotransferase (ALT) and aspartate aminotransferase (AST). We also investigated correlation between levels of liver enzymes and some components of MS in both groups of patients. Methods: This cross-sectional study included 96 patients (age 47–83 years) with T2DM. All patients were divided according to the criteria of the National Cholesterol Education Program (NCEP) in two groups: 50 patients with T2 DM and MS (T2DM-MS) and 46 patients with T2DM without MS (T2DM-Non MS). The analysis included blood pressure monitoring and laboratory tests: fasting blood glucose (FBG), total lipoprotein cholesterol (TC), high-density lipoprotein cholesterol (HDL-C), triglyceride (TG), fibrinogen and liver enzymes: GGT, ALT and AST. T2DM-MS group included patients which had FBG ≥ 6,1 mmol/L, TG ≥ 1,7 mmol/L and blood pressure ≥ 130/85 mm Hg. Results: T2DM-MS patients had significant higher values of systolic blood pressure, diastolic blood pressure and medium arterial pressure compared to T2DM-Non MS patients. Serum levels of TC, TG, LDL-C, VLDL-C and FBG were significantly higher in the T2DM-MS group compared to the T2DM-Non MS group. Serum fibrinogen level and GGT level were significantly higher in patients with T2DM-MS compared to the serum fibrinogen level and GGT level in T2DM-Non MS patients. Mean serum AST and ALT level were higher, but not significantly, in patients with T2DM and MS compared to the patients with T2DM without MS. Significant negative correlations were observed between TC and AST (r= -0,28, p<0,05), as well as between TC and ALT level (r= -0,29, p<0,05) in T2DM-MS group of patients. Conclusion: These results suggest that patients with T2DM and MS have markedly elevated liver enzymes. T2DM and MS probably play a role in

  11. Driving the need to feed: Insight into the collaborative interaction between ghrelin and endocannabinoid systems in modulating brain reward systems.

    Science.gov (United States)

    Edwards, Alexander; Abizaid, Alfonso

    2016-07-01

    Independent stimulation of either the ghrelin or endocannabinoid system promotes food intake and increases adiposity. Given the similar distribution of their receptors in feeding associated brain regions and organs involved in metabolism, it is not surprising that evidence of their interaction and its importance in modulating energy balance has emerged. This review documents the relationship between ghrelin and endocannabinoid systems within the periphery and hypothalamus (HYP) before presenting evidence suggesting that these two systems likewise work collaboratively within the ventral tegmental area (VTA) to modulate non-homeostatic feeding. Mechanisms, consistent with current evidence and local infrastructure within the VTA, will be proposed. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. 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

  13. Regulation of brain reward by the endocannabinoid system: a critical review of behavioral studies in animals.

    Science.gov (United States)

    Vlachou, S; Panagis, G

    2014-01-01

    The endocannabinoid system has been implicated in the regulation of a variety of physiological processes, including a crucial involvement in brain reward systems and the regulation of motivational processes. Behavioral studies have shown that cannabinoid reward may involve the same brain circuits and similar brain mechanisms with other drugs of abuse, such as nicotine, cocaine, alcohol and heroin, as well as natural rewards, such as food, water and sucrose, although the conditions under which cannabinoids exert their rewarding effects may be more limited. The purpose of the present review is to briefly describe and evaluate the behavioral and pharmacological research concerning the major components of the endocannabinoid system and reward processes. Special emphasis is placed on data received from four procedures used to test the effects of the endocannabinoid system on brain reward in animals; namely, the intracranial self-stimulation paradigm, the self-administration procedure, the conditioned place preference procedure and the drug-discrimination procedure. The effects of cannabinoid 1 (CB1) and cannabinoid 2 (CB2) receptor agonists, antagonists and endocannabinoid modulators in these procedures are examined. Further, the involvement of CB1 and CB2 receptors, as well the fatty acid amid hydrolase (FAAH) enzyme in reward processes is investigated through presentation of respective genetic ablation studies in mice. We suggest that the endocannabinoid system plays a major role in modulating motivation and reward processes. Further research will provide us with a better understanding of these processes and, thus, could lead to the development of potential therapeutic compounds for the treatment of reward-related disorders.

  14. Characterization of Genes Encoding Key Enzymes Involved in Anthocyanin Metabolism of Kiwifruit during Storage Period.

    Science.gov (United States)

    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 effectively enhance the anthocyanin accumulation of kiwifruit in the end of storage period (90 days), which related to the increase in mRNA levels of ANS1, ANS2, DRF1, DRF2 , and UGFT2 . Moreover, the transcript abundance of MYBA1-1 and MYB5-1 , the genes encoding an important component of MYB-bHLH-WD40 (MBW) complex, was up-regulated, possibly contributing to the induction of specific anthocyanin biosynthesis genes under the low temperature. To further investigate the roles of AcMYB5-1/5-2/A1-1 in regulation of anthocyanin biosynthesis, genes encoding the three transcription factors were transiently transformed in Nicotiana benthamiana leaves. Overexpression of AcMYB5-1/5-2/A1-1 activated the gene expression of NtANS and NtDFR in tobacco. Our results suggested that low temperature storage could stimulate the anthocyanin accumulation in harvested kiwifruit via regulating several structural and regulatory genes involved in anthocyanin biosynthesis.

  15. Acetaminophen induces xenobiotic-metabolizing enzymes in rat: Impact of a uranium chronic exposure.

    Science.gov (United States)

    Rouas, Caroline; Souidi, Maâmar; Grandcolas, Line; Grison, Stephane; Baudelin, Cedric; Gourmelon, Patrick; Pallardy, Marc; Gueguen, Yann

    2009-11-01

    The extensive use of uranium in civilian and military applications increases the risk of human chronic exposure. Uranium is a slightly radioactive heavy metal with a predominantly chemical toxicity, especially in kidney but also in liver. Few studies have previously shown some effects of uranium on xenobiotic-metabolizing enzymes (XME) that might disturb drug pharmacokinetic. The aim of this study was to determine whether a chronic (9 months) non-nephrotoxic low dose exposure to depleted uranium (DU, 1mg/rat/day) could modify the liver XME, using a single non-hepatotoxic acetaminophen (APAP) treatment (50mg/kg). Most of XME analysed were induced by APAP treatment at the gene expression level but at the protein level only CYP3A2 was significantly increased 3h after APAP treatment in DU-exposed rats whereas it remained at a basal level in unexposed rats. In conclusion, these results showed that a chronic non-nephrotoxic DU exposure specially modify CYP3A2 after a single therapeutic APAP treatment. Copyright © 2009 Elsevier B.V. All rights reserved.

  16. Exercise Training positively modulates the Ectonucleotidase Enzymes in Lymphocytes of Metabolic Syndrome Patients.

    Science.gov (United States)

    Martins, C C; Bagatini, M D; Cardoso, A M; Zanini, D; Abdalla, F H; Baldissarelli, J; Dalenogare, D P; Dos Santos, D L; Schetinger, M R C; Morsch, V M M

    2016-11-01

    In this study, we investigated the cardiovascular risk factors as well as ectonucleotidase activities in lymphocytes of metabolic syndrome (MetS) patients before and after an exercise intervention. 20 MetS patients, who performed regular concurrent exercise training for 30 weeks, 3 times/week, were studied. Anthropometric, biochemical, inflammatory and hepatic parameters and hydrolysis of adenine nucleotides and nucleoside in lymphocytes were collected from patients before and after 15 and 30 weeks of the exercise intervention as well as from participants of the control group. An increase in the hydrolysis of ATP and ADP, and a decrease in adenosine deamination in lymphocytes of MetS patients before the exercise intervention were observed (Pexercise training after 30 weeks of intervention. Additionally, exercise training reduced the inflammatory and hepatic markers to baseline levels after 30 weeks of exercise. Our results clearly indicated alteration in ectonucleotidase enzymes in lymphocytes in the MetS, whereas regular exercise training had a protective effect on the enzymatic alterations and on inflammatory and hepatic parameters, especially if it is performed regularly and for a long period. © Georg Thieme Verlag KG Stuttgart · New York.

  17. Inhibitory effects of kale ingestion on metabolism by cytochrome P450 enzymes in rats.

    Science.gov (United States)

    Yamasaki, Izumi; Yamada, Masayoshi; Uotsu, Nobuo; Teramoto, Sachiyuki; Takayanagi, Risa; Yamada, Yasuhiko

    2012-01-01

    Kale (Brassica oleracea L. var acephala DC) is a leafy green vegetable belonging to the cabbage family (Brassicaceae) that contains a large amount of health-promoting phytochemicals. There are any reports about the effects of kale ingestion on the chemoprevention function and mechanism, but the interactions between kale and drugs have not been researched. We investigated the effects of kale intake on cytochrome P450 (CYP) metabolism by using cocktail probe drugs, including midazolam (for CYP3A4), caffeine (for CYP1A2), dextromethorphan (for CYP2D6), tolbutamide (for CYP2C9), omeprazole (for CYP2C19), and chlorzoxazone (for CYP2E1). Cocktail drugs were administered into rats treated with kale and cabbage (2000 mg/kg) for a week. The results showed that kale intake induced a significant increase in plasma levels and the AUC of midazolam, caffeine, and dextromethorphan. In addition, the plasma concentration and AUC of omeprazole tended to increase. Additionally, no almost differences in the mRNA expression levels of CYP enzymes in the liver were observed. In conclusion, kale ingestion was considered to have an inhibitory effect on the activities of CYP3A4, 1A2, 2D6, and 2C19 for a reason competitive inhibition than inhibitory changes in the mRNA expressions.

  18. 3'-Azido-3'-deoxythymidine (AZT) induces apoptosis and alters metabolic enzyme activity in human placenta

    International Nuclear Information System (INIS)

    Collier, Abby C.; Helliwell, Rachel J.A.; Keelan, Jeffrey A.; Paxton, James W.; Mitchell, Murray D.; Tingle, Malcolm D.

    2003-01-01

    The anti-HIV drug 3'-azido-3'-deoxythymidine (AZT) is the drug of choice for preventing maternal-fetal HIV transmission during pregnancy. Our aim was to assess the cytotoxic effects of AZT on human placenta in vitro. The mechanisms of AZT-induced effects were investigated using JEG-3 choriocarcinoma cells and primary explant cultures from term and first-trimester human placentas. Cytotoxicity measures included trypan blue exclusion, MTT, and reactive oxygen species (ROS) assays. Apoptosis was measured with an antibody specific to cleaved caspase-3 and by rescue of cells by the general caspase inhibitor Boc-D-FMK. The effect of AZT on the activities of glutathione-S-transferase, β-glucuronidase, UDP-glucuronosyl transferase, cytochrome P450 (CYP) 1A, and CYP reductase (CYPR) in the placenta was assessed using biochemical assays and immunoblotting. AZT increased ROS levels, decreased cellular proliferation rates, was toxic to mitochondria, and initiated cell death by a caspase-dependent mechanism in the human placenta in vitro. In the absence of serum, the effects of AZT were amplified in all the models used. AZT also increased the amounts of activity of GST, β-glucuronidase, and CYP1A, whereas UGT and CYPR were decreased. We conclude that AZT causes apoptosis in the placenta and alters metabolizing enzymes in human placental cells. These findings have implications for the safe administration of AZT in pregnancy with respect to the maintenance of integrity of the maternal-fetal barrier

  19. Effects of Adolescent Intermittent Alcohol Exposure on the Expression of Endocannabinoid Signaling-Related Proteins in the Spleen of Young Adult Rats

    Science.gov (United States)

    Vázquez, Mariam; Sánchez, Laura; Rivera, Patricia; Gavito, Ana; Mela, Virginia; Alén, Francisco; Decara, Juan; Suárez, Juan; Giné, Elena; López-Moreno, José Antonio; Chowen, Julie; Rodríguez-de-Fonseca, Fernando; Serrano, Antonia; Viveros, María Paz

    2016-01-01

    Intermittent alcohol exposure is a common pattern of alcohol consumption among adolescents and alcohol is known to modulate the expression of the endocannabinoid system (ECS), which is involved in metabolism and inflammation. However, it is unknown whether this pattern may have short-term consequences on the ECS in the spleen. To address this question, we examined the plasma concentrations of metabolic and inflammatory signals and the splenic ECS in early adult rats exposed to alcohol during adolescence. A 4-day drinking in the dark (DID) procedure for 4 weeks was used as a model of intermittent forced-alcohol administration (20%, v/v) in female and male Wistar rats, which were sacrificed 2 weeks after the last DID session. First, there was no liver damage or alterations in plasma metabolic parameters. However, certain plasma inflammatory signals were altered according to sex and alcohol exposition. Whereas fractalkine [chemokine (C-X3-C motif) ligand 1] was only affected by sex with lower concentration in male rats, there was an interaction between sex and alcohol exposure in the TNF-α and interleukin-6 concentrations and only female rats displayed changes. Regarding the mRNA and protein expression of the ECS, the receptors and endocannabinoid-synthesizing enzymes were found to be altered with area-specific expression patterns in the spleen. Overall, whereas the expression of the cannabinoid receptor CB1 and the nuclear peroxisome proliferator-activated receptor PPARα were lower in alcohol-exposed rats compared to control rats, the CB2 expression was higher. Additionally, the N-acyl-phosphatidylethanolamine-specific phospholipase D expression was high in female alcohol-exposed rats and low in male alcohol-exposed rats. In conclusion, intermittent alcohol consumption during adolescence may be sufficient to induce short-term changes in the expression of splenic endocannabinoid signaling-related proteins and plasma pro-inflammatory cytokines in young adult rats

  20. Effects of Adolescent Intermittent Alcohol Exposure on the Expression of Endocannabinoid Signaling-Related Proteins in the Spleen of Young Adult Rats.

    Directory of Open Access Journals (Sweden)

    Francisco Javier Pavón

    Full Text Available Intermittent alcohol exposure is a common pattern of alcohol consumption among adolescents and alcohol is known to modulate the expression of the endocannabinoid system (ECS, which is involved in metabolism and inflammation. However, it is unknown whether this pattern may have short-term consequences on the ECS in the spleen. To address this question, we examined the plasma concentrations of metabolic and inflammatory signals and the splenic ECS in early adult rats exposed to alcohol during adolescence. A 4-day drinking in the dark (DID procedure for 4 weeks was used as a model of intermittent forced-alcohol administration (20%, v/v in female and male Wistar rats, which were sacrificed 2 weeks after the last DID session. First, there was no liver damage or alterations in plasma metabolic parameters. However, certain plasma inflammatory signals were altered according to sex and alcohol exposition. Whereas fractalkine [chemokine (C-X3-C motif ligand 1] was only affected by sex with lower concentration in male rats, there was an interaction between sex and alcohol exposure in the TNF-α and interleukin-6 concentrations and only female rats displayed changes. Regarding the mRNA and protein expression of the ECS, the receptors and endocannabinoid-synthesizing enzymes were found to be altered with area-specific expression patterns in the spleen. Overall, whereas the expression of the cannabinoid receptor CB1 and the nuclear peroxisome proliferator-activated receptor PPARα were lower in alcohol-exposed rats compared to control rats, the CB2 expression was higher. Additionally, the N-acyl-phosphatidylethanolamine-specific phospholipase D expression was high in female alcohol-exposed rats and low in male alcohol-exposed rats. In conclusion, intermittent alcohol consumption during adolescence may be sufficient to induce short-term changes in the expression of splenic endocannabinoid signaling-related proteins and plasma pro-inflammatory cytokines in

  1. Effects of Curcuma xanthorrhiza Extracts and Their Constituents on Phase II Drug-metabolizing Enzymes Activity.

    Science.gov (United States)

    Salleh, Nurul Afifah Mohd; Ismail, Sabariah; Ab Halim, Mohd Rohaimi

    2016-01-01

    Curcuma xanthorrhiza is a native Indonesian plant and traditionally utilized for a range of illness including liver damage, hypertension, diabetes, and cancer. The study determined the effects of C. xanthorrhiza extracts (ethanol and aqueous) and their constituents (curcumene and xanthorrhizol) on UDP-glucuronosyltransferase (UGT) and glutathione transferase (GST) activities. The inhibition studies were evaluated both in rat liver microsomes and in human recombinant UGT1A1 and UGT2B7 enzymes. p-nitrophenol and beetle luciferin were used as the probe substrates for UGT assay while 1-chloro-2,4-dinitrobenzene as the probe for GST assay. The concentrations of extracts studied ranged from 0.1 to 1000 μg/mL while for constituents ranged from 0.01 to 500 μM. In rat liver microsomes, UGT activity was inhibited by the ethanol extract (IC 50 =279.74 ± 16.33 μg/mL). Both UGT1A1 and UGT2B7 were inhibited by the ethanol and aqueous extracts with IC 50 values ranging between 9.59-22.76 μg/mL and 110.71-526.65 μg/Ml, respectively. Rat liver GST and human GST Pi-1 were inhibited by ethanol and aqueous extracts, respectively (IC 50 =255.00 ± 13.06 μg/mL and 580.80 ± 18.56 μg/mL). Xanthorrhizol was the better inhibitor of UGT1A1 (IC 50 11.30 ± 0.27 μM) as compared to UGT2B7 while curcumene did not show any inhibition. For GST, both constituents did not show any inhibition. These findings suggest that C. xanthorrhiza have the potential to cause herb-drug interaction with drugs that are primarily metabolized by UGT and GST enzymes. Findings from this study would suggest which of Curcuma xanthorrhiza extracts and constituents that would have potential interactions with drugs which are highly metabolized by UGT and GST enzymes. Further clinical studies can then be designed if needed to evaluate the in vivo pharmacokinetic relevance of these interactions Abbreviations Used : BSA: Bovine serum albumin, CAM: Complementary and alternative medicine, cDNA: Complementary

  2. Effects of Curcuma xanthorrhiza Extracts and Their Constituents on Phase II Drug-metabolizing Enzymes Activity

    Science.gov (United States)

    Salleh, Nurul Afifah Mohd; Ismail, Sabariah; Ab Halim, Mohd Rohaimi

    2016-01-01

    Background: Curcuma xanthorrhiza is a native Indonesian plant and traditionally utilized for a range of illness including liver damage, hypertension, diabetes, and cancer. Objective: The study determined the effects of C. xanthorrhiza extracts (ethanol and aqueous) and their constituents (curcumene and xanthorrhizol) on UDP-glucuronosyltransferase (UGT) and glutathione transferase (GST) activities. Materials and Methods: The inhibition studies were evaluated both in rat liver microsomes and in human recombinant UGT1A1 and UGT2B7 enzymes. p-nitrophenol and beetle luciferin were used as the probe substrates for UGT assay while 1-chloro-2,4-dinitrobenzene as the probe for GST assay. The concentrations of extracts studied ranged from 0.1 to 1000 μg/mL while for constituents ranged from 0.01 to 500 μM. Results: In rat liver microsomes, UGT activity was inhibited by the ethanol extract (IC50 =279.74 ± 16.33 μg/mL). Both UGT1A1 and UGT2B7 were inhibited by the ethanol and aqueous extracts with IC50 values ranging between 9.59–22.76 μg/mL and 110.71–526.65 μg/Ml, respectively. Rat liver GST and human GST Pi-1 were inhibited by ethanol and aqueous extracts, respectively (IC50 =255.00 ± 13.06 μg/mL and 580.80 ± 18.56 μg/mL). Xanthorrhizol was the better inhibitor of UGT1A1 (IC50 11.30 ± 0.27 μM) as compared to UGT2B7 while curcumene did not show any inhibition. For GST, both constituents did not show any inhibition. Conclusion: These findings suggest that C. xanthorrhiza have the potential to cause herb-drug interaction with drugs that are primarily metabolized by UGT and GST enzymes. SUMMARY Findings from this study would suggest which of Curcuma xanthorrhiza extracts and constituents that would have potential interactions with drugs which are highly metabolized by UGT and GST enzymes. Further clinical studies can then be designed if needed to evaluate the in vivo pharmacokinetic relevance of these interactions Abbreviations Used: BSA: Bovine serum albumin

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

    Science.gov (United States)

    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.

  4. 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.

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

    Science.gov (United States)

    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

  6. The endocannabinoid system and nondrug rewarding behaviours.

    Science.gov (United States)

    Fattore, Liana; Melis, Miriam; Fadda, Paola; Pistis, Marco; Fratta, Walter

    2010-07-01

    Rewarding behaviours such as sexual activity, eating, nursing, parenting, social interactions, and play activity are conserved strongly in evolution, and they are essential for development and survival. All of these behaviours are enjoyable and represent pleasant experiences with a high reward value. Remarkably, rewarding behaviours activate the same brain circuits that mediate the positive reinforcing effects of drugs of abuse and of other forms of addiction, such as gambling and food addiction. Given the involvement of the endocannabinoid system in a variety of physiological functions of the nervous system, it is not surprising that it takes part in the complex machinery that regulates gratification and perception of pleasure. In this review, we focus first on the role of the endocannabinoid system in the modulation of neural activity and synaptic functions in brain regions that are involved in natural and nonnatural rewards (namely, the ventral tegmental area, striatum, amygdala, and prefrontal cortex). Then, we examine the role of the endocannabinoid system in modulating behaviours that directly or indirectly activate these brain reward pathways. More specifically, current knowledge of the effects of the pharmacological manipulation of the endocannabinoid system on natural (eating, sexual behaviour, parenting, and social play) and pathological (gambling) rewarding behaviours is summarised and discussed. Copyright 2010 Elsevier Inc. All rights reserved.

  7. The endocannabinoid system: emotion, learning and addiction.

    Science.gov (United States)

    Moreira, Fabrício A; Lutz, Beat

    2008-06-01

    The identification of the cannabinoid receptor type 1 (CB1 receptor) was the milestone discovery in the elucidation of the behavioural and emotional responses induced by the Cannabis sativa constituent Delta(9)-tetrahydrocannabinol. The subsequent years have established the existence of the endocannabinoid system. The early view relating this system to emotional responses is reflected by the fact that N-arachidonoyl ethanolamine, the pioneer endocannabinoid, was named anandamide after the Sanskrit word 'ananda', meaning 'bliss'. However, the emotional responses to cannabinoids are not always pleasant and delightful. Rather, anxiety and panic may also occur after activation of CB1 receptors. The present review discusses three properties of the endocannabinoid system as an attempt to understand these diverse effects. First, this system typically functions 'on-demand', depending on environmental stimuli and on the emotional state of the organism. Second, it has a wide neuro-anatomical distribution, modulating brain regions with different functions in responses to aversive stimuli. Third, endocannabinoids regulate the release of other neurotransmitters that may have even opposing functions, such as GABA and glutamate. Further understanding of the temporal, spatial and functional characteristics of this system is necessary to clarify its role in emotional responses and will promote advances in its therapeutic exploitation.

  8. Targeting the endocannabinoid system : future therapeutic strategies

    NARCIS (Netherlands)

    Aizpurua-Olaizola, Oier; Elezgarai, Izaskun; Rico-Barrio, Irantzu; Zarandona, Iratxe; Etxebarria, Nestor; Usobiaga, Aresatz

    2017-01-01

    The endocannabinoid system (ECS) is involved in many physiological regulation pathways in the human body, which makes this system the target of many drugs and therapies. In this review, we highlight the latest studies regarding the role of the ECS and the drugs that target it, with a particular

  9. 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

  10. The endocannabinoid system in brain reward processes.

    Science.gov (United States)

    Solinas, M; Goldberg, S R; Piomelli, D

    2008-05-01

    Food, drugs and brain stimulation can serve as strong rewarding stimuli and are all believed to activate common brain circuits that evolved in mammals to favour fitness and survival. For decades, endogenous dopaminergic and opioid systems have been considered the most important systems in mediating brain reward processes. Recent evidence suggests that the endogenous cannabinoid (endocannabinoid) system also has an important role in signalling of rewarding events. First, CB(1) receptors are found in brain areas involved in reward processes, such as the dopaminergic mesolimbic system. Second, activation of CB(1) receptors by plant-derived, synthetic or endogenous CB(1) receptor agonists stimulates dopaminergic neurotransmission, produces rewarding effects and increases rewarding effects of abused drugs and food. Third, pharmacological or genetic blockade of CB(1) receptors prevents activation of dopaminergic neurotransmission by several addictive drugs and reduces rewarding effects of food and these drugs. Fourth, brain levels of the endocannabinoids anandamide and 2-arachidonoylglycerol are altered by activation of reward processes. However, the intrinsic activity of the endocannabinoid system does not appear to play a facilitatory role in brain stimulation reward and some evidence suggests it may even oppose it. The influence of the endocannabinoid system on brain reward processes may depend on the degree of activation of the different brain areas involved and might represent a mechanism for fine-tuning dopaminergic activity. Although involvement of the various components of the endocannabinoid system may differ depending on the type of rewarding event investigated, this system appears to play a major role in modulating reward processes.

  11. The Endocannabinoid System Modulating Levels of Consciousness, Emotions and Likely Dream Contents.

    Science.gov (United States)

    Murillo-Rodriguez, Eric; Pastrana-Trejo, Jose Carlos; Salas-Crisóstomo, Mireille; de-la-Cruz, Miriel

    2017-01-01

    Cannabinoids are derivatives that are either compounds occurring naturally in the plant, Cannabis sativa or synthetic analogs of these molecules. The first and most widely investigated of the cannabinoids is Δ9-tetrahydrocannabinol (Δ9-THC), which is the main psychotropic constituent of cannabis and undergoes significant binding to cannabinoid receptors. These cannabinoid receptors are seven-transmembrane receptors that received their name from the fact that they respond to cannabinoid compounds, including Δ9-THC. The cannabinoid receptors have been described in rat, human and mouse brains and they have been named the CB1 and CB2 cannabinoid receptors. Later, an endogenous molecule that exerts pharmacological effects similar to those described by Δ9-THC and binds to the cannabinoid receptors was discovered. This molecule, named anandamide, was the first of five endogenous cannabinoid receptor agonists described to date in the mammalian brain and other tissues. Of these endogenous cannabinoids or endocannabinoids, the most thoroughly investigated to date have been anandamide and 2-arachidonoylglycerol (2-AG). Over the years, a significant number of articles have been published in the field of endogenous cannabinoids, suggesting a modulatory profile in multiple neurobiological roles of endocannabinoids. The general consensus accepts that the endogenous cannabinoid system includes natural ligands (such as anandamide and 2- AG), receptors (CB1 and CB2), and the main enzymes responsible for the hydrolysis of anandamide and 2-AG (fatty acid amide hydrolase [FAAH] and monoacylglycerol lipase [MAGL], respectively) as well as the anandamide membrane transporter (AMT). To date, diverse pieces of evidence have shown that the endocannabinoid system controls multiple functions such as feeding, pain, learning and memory and has been linked with various disturbances, such as Parkinson´s disease. Among the modulatory properties of the endocannabinoid system, current data

  12. Hepatic xenobiotic metabolizing enzyme and transporter gene expression through the life stages of the mouse.

    Directory of Open Access Journals (Sweden)

    Janice S Lee

    Full Text Available BACKGROUND: Differences in responses to environmental chemicals and drugs between life stages are likely due in part to differences in the expression of xenobiotic metabolizing enzymes and transporters (XMETs. No comprehensive analysis of the mRNA expression of XMETs has been carried out through life stages in any species. RESULTS: Using full-genome arrays, the mRNA expression of all XMETs and their regulatory proteins was examined during fetal (gestation day (GD 19, neonatal (postnatal day (PND 7, prepubescent (PND32, middle age (12 months, and old age (18 and 24 months in the C57BL/6J (C57 mouse liver and compared to adults. Fetal and neonatal life stages exhibited dramatic differences in XMET mRNA expression compared to the relatively minor effects of old age. The total number of XMET probe sets that differed from adults was 636, 500, 84, 5, 43, and 102 for GD19, PND7, PND32, 12 months, 18 months and 24 months, respectively. At all life stages except PND32, under-expressed genes outnumbered over-expressed genes. The altered XMETs included those in all of the major metabolic and transport phases including introduction of reactive or polar groups (Phase I, conjugation (Phase II and excretion (Phase III. In the fetus and neonate, parallel increases in expression were noted in the dioxin receptor, Nrf2 components and their regulated genes while nuclear receptors and regulated genes were generally down-regulated. Suppression of male-specific XMETs was observed at early (GD19, PND7 and to a lesser extent, later life stages (18 and 24 months. A number of female-specific XMETs exhibited a spike in expression centered at PND7. CONCLUSIONS: The analysis revealed dramatic differences in the expression of the XMETs, especially in the fetus and neonate that are partially dependent on gender-dependent factors. XMET expression can be used to predict life stage-specific responses to environmental chemicals and drugs.

  13. Up-regulation of sucrose metabolizing enzymes in Oncidium goldiana grown under elevated carbon dioxide

    Energy Technology Data Exchange (ETDEWEB)

    Chang Run Li; Sun, W.Q.; Choy Sin Hew [National Univ. of Singapore. dept. of Biological Sciences (Singapore)

    2001-07-01

    Experiments were conducted in controlled growth chambers to evaluate how increase in CO{sub 2} concentration affected sucrose metabolizing enzymes, especially sucrose phosphate synthase (SPS; EC 2.4.1.14) and sucrose synthase (SS; EC 2.4.1.13), as well as carbon metabolism and partitioning in a tropical epiphytic orchid species (Oncidium goldiana). Response of ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco; EC 4.1.1.39) to elevated CO{sub 2} was determined along with dry mass production, photosynthesis rate, chlorophyll content, total nitrogen and total soluble protein content. After 60 days of growth, there was a 80% and 150% increase in dry mass production in plants grown at 750 and 1100 {mu} l{sup -}1 CO{sub 2}, respectively, compared with those grown at ambient CO{sub 2} (about 370 {mu} l{sup -}1). A similar increase in photosynthesis rate was detected throughout the growth period when measured under growth CO{sub 2} conditions. Concomitantly, there was a decline in leaf Rubisco activity in plants in elevated CO{sub 2} after 10 days of growth. Over the growth period, leaf SPS and SS activities were up-regulated by an average of 20% and 40% for plants grown at 750 and 1100 {mu} l{sup -}1 CO{sub 2}, respectively. Leaf sucrose content and starch content were significantly higher throughout the growth period in plants grown at elevated CO{sub 2} than those at ambient CO{sub 2}. The partitioning of photosynthetically fixed carbon between sucrose and starch appeared to be unaffected by the 750 {mu} l{sup -}1 CO{sub 2} treatment, but it was favored into starch under the 1100 {mu} l{sup -}1 CO{sub 2} condition. The activities of SPS and SS in leaf extracts were closely associated with photosynthetic rates and with partitioning of carbon between starch and sucrose in leaves. The data are consistent with the hypothesis that the up-regulation of leaf SPS and SS might be an acclimation response to optimize the utilization and export of organic carbon with the

  14. Genetic Disruption of 2-Arachidonoylglycerol Synthesis Reveals a Key Role for Endocannabinoid Signaling in Anxiety Modulation

    Directory of Open Access Journals (Sweden)

    Brian C. Shonesy

    2014-12-01

    Full Text Available Summary: Endocannabinoid (eCB signaling has been heavily implicated in the modulation of anxiety and depressive behaviors and emotional learning. However, the role of the most-abundant endocannabinoid 2-arachidonoylglycerol (2-AG in the physiological regulation of affective behaviors is not well understood. Here, we show that genetic deletion of the 2-AG synthetic enzyme diacylglycerol lipase α (DAGLα in mice reduces brain, but not circulating, 2-AG levels. DAGLα deletion also results in anxiety-like and sex-specific anhedonic phenotypes associated with impaired activity-dependent eCB retrograde signaling at amygdala glutamatergic synapses. Importantly, acute pharmacological normalization of 2-AG levels reverses both phenotypes of DAGLα-deficient mice. These data suggest 2-AG deficiency could contribute to the pathogenesis of affective disorders and that pharmacological normalization of 2-AG signaling could represent an approach for the treatment of mood and anxiety disorders. : The role of the primary endogenous cannabinoid 2-AG in mood and anxiety regulation is not well understood. Shonesy et al. show that deletion of a primary 2-AG synthetic enzyme, DAGLα, results in anxiety and sex-specific depressive phenotypes, which can be rapidly reversed by pharmacological normalization of endocannabinoid levels.

  15. The Endocannabinoid System in the Retina: From Physiology to Practical and Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Thomas Schwitzer

    2016-01-01

    Full Text Available Cannabis is one of the most prevalent drugs used in industrialized countries. The main effects of Cannabis are mediated by two major exogenous cannabinoids: ∆9-tetrahydroxycannabinol and cannabidiol. They act on specific endocannabinoid receptors, especially types 1 and 2. Mammals are endowed with a functional cannabinoid system including cannabinoid receptors, ligands, and enzymes. This endocannabinoid signaling pathway is involved in both physiological and pathophysiological conditions with a main role in the biology of the central nervous system. As the retina is a part of the central nervous system due to its embryonic origin, we aim at providing the relevance of studying the endocannabinoid system in the retina. Here, we review the distribution of the cannabinoid receptors, ligands, and enzymes in the retina and focus on the role of the cannabinoid system in retinal neurobiology. This review describes the presence of the cannabinoid system in critical stages of retinal processing and its broad involvement in retinal neurotransmission, neuroplasticity, and neuroprotection. Accordingly, we support the use of synthetic cannabinoids as new neuroprotective drugs to prevent and treat retinal diseases. Finally, we argue for the relevance of functional retinal measures in cannabis users to evaluate the impact of cannabis use on human retinal processing.

  16. 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.

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

    Science.gov (United States)

    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.

  18. Effects of tin-protoporphyrin administration on hepatic xenobiotic metabolizing enzymes in the juvenile rat

    International Nuclear Information System (INIS)

    Stout, D.L.; Becker, F.F.

    1988-01-01

    The heme analogue tin-protoporphyrin IX (SnP) is a potent inhibitor of microsomal heme oxygenase. Administration of SnP to neonatal rats can prevent hyperbilirubinemia by blocking the postnatal increase of heme oxygenase activity. Apparently innocuous at therapeutic doses, it is of potential clinical value for chemoprevention of neonatal jaundice. We found that when 50-g male Sprague-Dawley rats were treated daily with 50 mumol of SnP/kg sc for 6 days, hepatic microsomal cytochromes b5 and P-450 were significantly diminished. Cytochrome P-450 reductase, two P-450-dependent monooxygenases, aminopyrine demethylase and benzo(a)pyrene hydroxylase, and catalase, a peroxisomal hemoprotein, were also significantly diminished. These results suggested that SnP might significantly affect the metabolism of other xenobiotics. This possibility was confirmed by the finding that hexobarbital-induced sleep lasted 4 times longer in SnP-treated rats than in controls. Inhibition of protein synthesis by SnP was ruled out as the cause of hemoprotein loss when administration of [ 3 H]leucine to SnP-treated and control rats demonstrated that proteins of the microsomal, cytosolic, and plasma membrane fractions of the livers from both groups incorporated similar levels of leucine. When 55 FeCl 3 and [2- 14 C]glycine were administered to measure heme synthesis, heme extract from the livers of SnP-treated rats contained 4 times more label from iron and glycine than did heme from control livers. Despite the apparent increased rate of heme synthesis in SnP-treated rats, each of the three cell fractions demonstrated a significant loss of heme but contained sizable amounts of SnP. These findings suggest that SnP causes a decrease of functional hemoprotein and partial loss of enzymic activity by displacing intracellular heme

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

    Science.gov (United States)

    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.

  20. Effect of UV-B on enzymes of nitrogen metabolism in the cyanobacterium Nostoc calcicola

    International Nuclear Information System (INIS)

    Kumar, A.; Sinha, R.P.; Häder, D. P.

    1996-01-01

    The effects of ultraviolet-B (UV-B; 280–315 nm) irradiation on nitrogenase and nitrate reductase (NR) activity have been studied in the filamentous and heterocystous N 2 -fixing cyanobacterium Nostoc calcicola. Exposure of cultures to UV-B (5W/m 2 ) for as little as 30 min caused complete inactivation of nitrogenase activity whereas nitrate reductase activity was stimulated twofold in comparison to one exposed to fluorescent white light. GS activity was also inhibited by UV-B treatment, but there was no total loss of activity even after 4 h. NR activity showed a gradual stimulation up to 4 h and thereafter it became constant. Stimulation was also obtained in reductant deficient cultures (12 h incubation in the dark) suggesting independence of NR of PS-II under UV-B. NR activity was also unaffected in the presence of DCMU, a known inhibitor of PS-II. However, both O 2 evolution and 14 CO 2 uptake were completely abolished following 30 min of UV-B treatment. Addition of the protein synthesis inhibitor chloramphenicol (25 μg/mL) to cultures did not show any inhibitory effect on NR activity. SDS-PAGE analysis of UV-B treated cultures elicited gradual loss of protein bands with increasing duration of exposure. Our findings suggest that UV-B irradiance has differential effects on the enzymes of the nitrogen metabolism in the cyanobacterium Nostoc calcicola. Further studies are needed to reveal the exact mechanism involved in the stimulation of NR activity by UV-B. Whether UV-B has a direct effect on NO 2 − accumulation in the cells needs detailed investigation. (author)

  1. 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.

  2. Metabolic imidacloprid resistance in the brown planthopper, Nilaparvata lugens, relies on multiple P450 enzymes.

    Science.gov (United States)

    Zhang, Yixi; Yang, Yuanxue; Sun, Huahua; Liu, Zewen

    2016-12-01

    Target insensitivity contributing to imidacloprid resistance in Nilaparvata lugens has been reported to occur either through point mutations or quantitative change in nicotinic acetylcholine receptors (nAChRs). However, the metabolic resistance, especially the enhanced detoxification by P450 enzymes, is the major mechanism in fields. From one field-originated N. lugens population, an imidacloprid resistant strain G25 and a susceptible counterpart S25 were obtained to analyze putative roles of P450s in imidacloprid resistance. Compared to S25, over-expression of twelve P450 genes was observed in G25, with ratios above 5.0-fold for CYP6AY1, CYP6ER1, CYP6CS1, CYP6CW1, CYP4CE1 and CYP425B1. RNAi against these genes in vivo and recombinant tests on the corresponding proteins in vitro revealed that four P450s, CYP6AY1, CYP6ER1, CYP4CE1 and CYP6CW1, played important roles in imidacloprid resistance. The importance of the four P450s was not equal at different stages of resistance development based on their over-expression levels, among which CYP6ER1 was important at all stages, and that the others might only contribute at certain stages. The results indicated that, to completely reflect roles of P450s in insecticide resistances, their over-expression in resistant individuals, expression changes at the stages of resistance development, and catalytic activities against insecticides should be considered. In this study, multiple P450s, CYP6AY1, CYP6ER1, CYP4CE1 and CYP6CW1, have proven to be important in imidacloprid resistance. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Genetic variation in alcohol metabolizing enzymes among Inuit and its relation to drinking patterns.

    Science.gov (United States)

    Bjerregaard, Peter; Mikkelsen, Stine Schou; Becker, Ulrik; Hansen, Torben; Tolstrup, Janne S

    2014-11-01

    Variation in genes involved in alcohol metabolism is associated with drinking patterns worldwide. We compared variation in these genes among the Inuit with published results from the general population of Denmark and, due to the Asian ancestry of the Inuit, with Han Chinese. We analyzed the association between gene variations and drinking patterns among the Inuit. We genotyped 4162 Inuit participants from two population health surveys. Information on drinking patterns was available for 3560. Seven single nucleotide polymorphisms (SNPs) were examined: ADH1B arg48his, ADH1C ile350val, ADH1C arg272gln, ALDH2 glu504lys, ALDH2 5'-UTR A-357G, ALDH1B1 ala86val and ALDH1B1 arg107leu. The allele distribution differed significantly between Inuit and the general population of Denmark. A protective effect on heavy drinking was found for the TT genotype of the ALDH1B1 arg107leu SNP (OR=0.59; 95% CI 0.37-0.92), present in 3% of pure Inuit and 37% of Danes. The ADH1C GG genotype was associated with heavy drinking and a positive CAGE test (OR 1.34; 95% CI 1.05-1.72). It was present in 27% of Inuit and 18% of Danes. The Asian genotype pattern with a high frequency of the ADH1B A allele and an ALDH2 gene coding for an inactive enzyme was not present in Greenland. ADH1C and ALDH1B1 arg107leu SNPs play a role in the shaping of drinking patterns among the Inuit in Greenland. A low frequency of the ALDH1B1 arg107leu TT genotype compared with the general population in Denmark deserves further study. This genotype was protective of heavy drinking among the Inuit. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  4. OVER-EXPRESSION OF GENE ENCODING FATTY ACID METABOLIC ENZYMES IN FISH

    Directory of Open Access Journals (Sweden)

    Alimuddin Alimuddin

    2008-12-01

    Full Text Available Eicosapentaenoic acid (EPA, 20:5n-3 and docosahexaenoic acid (DHA, 22:6n-3 have important nutritional benefits in humans. EPA and DHA are mainly derived from fish, but the decline in the stocks of major marine capture fishes could result in these fatty acids being consumed less. Farmed fish could serve as promising sources of EPA and DHA, but they need these fatty acids in their diets. Generation of fish strains that are capable of synthesizing enough amounts of EPA/DHA from the conversion of α-linolenic acid (LNA, 18:3n-3 rich oils can supply a new EPA/DHA source. This may be achieved by over-expression of genes encoding enzymes involved in HUFA biosynthesis. In aquaculture, the successful of this technique would open the possibility to reduce the enrichment of live food with fish oils for marine fish larvae, and to completely substitute fish oils with plant oils without reducing the quality of flesh in terms of EPA and DHA contents. Here, three genes, i.e. Δ6-desaturase-like (OmΔ6FAD, Δ5-desaturase-like (OmΔ5FAD and elongase-like (MELO encoding EPA/DHA metabolic enzymes derived from masu salmon (Oncorhynchus masou were individually transferred into zebrafish (Danio rerio as a model to increase its ability for synthesizing EPA and DHA. Fatty acid analysis showed that EPA content in whole body of the second transgenic fish generation over-expressing OmΔ6FAD gene was 1.4 fold and that of DHA was 2.1 fold higher (P<0.05 than those in non-transgenic fish. The EPA content in whole body of transgenic fish over-expressing OmΔ5FAD gene was 1.21-fold, and that of DHA was 1.24-fold higher (P<0.05 than those in nontransgenic fish. The same patterns were obtained in transgenic fish over-expressing MELO gene. EPA content was increased by 1.30-fold and DHA content by 1.33-fold higher (P<0.05 than those in non-transgenic fish. The results of studies demonstrated that fatty acid content of fish can be enhanced by over

  5. 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.

  6. 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)

  7. 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

  8. The skeletal endocannabinoid system: clinical and experimental insights.

    Science.gov (United States)

    Raphael, Bitya; Gabet, Yankel

    2016-05-01

    Recently, there has been a rapidly growing interest in the role of cannabinoids in the regulation of skeletal remodeling and bone mass, addressed in basic, translational and clinical research. Since the first publications in 2005, there are more than 1000 publications addressing the skeletal endocannabinoid system. This review focuses on the roles of the endocannabinoid system in skeletal biology via the cannabinoid receptors CB1, CB2 and others. Endocannabinoids play important roles in bone formation, bone resorption and skeletal growth, and are sometimes age, gender, species and strain dependent. Controversies in the literature and potential therapeutic approaches targeting the endocannabinoid system in skeletal disorders are also discussed.

  9. Endocannabinoid System and Synaptic Plasticity: Implications for Emotional Responses

    Directory of Open Access Journals (Sweden)

    María-Paz Viveros

    2007-01-01

    Full Text Available The endocannabinoid system has been involved in the regulation of anxiety, and proposed as an inhibitory modulator of neuronal, behavioral and adrenocortical responses to stressful stimuli. Brain regions such as the amygdala, hippocampus and cortex, which are directly involved in the regulation of emotional behavior, contain high densities of cannabinoid CB1 receptors. Mutant mice lacking CB1 receptors show anxiogenic and depressive-like behaviors as well as an altered hypothalamus pituitary adrenal axis activity, whereas enhancement of endocannabinoid signaling produces anxiolytic and antidepressant-like effects. Genetic and pharmacological approaches also support an involvement of endocannabinoids in extinction of aversive memories. Thus, the endocannabinoid system appears to play a pivotal role in the regulation of emotional states. Endocannabinoids have emerged as mediators of short- and long- term synaptic plasticity in diverse brain structures. Despite the fact that most of the studies on this field have been performed using in vitro models, endocannabinoid-mediated plasticity might be considered as a plausible candidate underlying some of the diverse physiological functions of the endogenous cannabinoid system, including developmental, affective and cognitive processes. In this paper, we will focus on the functional relevance of endocannabinoid-mediated plasticity within the framework of emotional responses. Alterations of the endocannabinoid system may constitute an important factor in the aetiology of certain neuropsychiatric disorders, and, in turn, enhancers of endocannabinoid signaling could represent a potential therapeutical tool in the treatment of both anxiety and depressive symptoms.

  10. Mitochondrial thiol modification by a targeted electrophile inhibits metabolism in breast adenocarcinoma cells by inhibiting enzyme activity and protein levels

    Directory of Open Access Journals (Sweden)

    M. Ryan Smith

    2016-08-01

    Full Text Available Many cancer cells follow an aberrant metabolic program to maintain energy for rapid cell proliferation. Metabolic reprogramming often involves the upregulation of glutaminolysis to generate reducing equivalents for the electron transport chain and amino acids for protein synthesis. Critical enzymes involved in metabolism possess a reactive thiolate group, which can be modified by certain oxidants. In the current study, we show that modification of mitochondrial protein thiols by a model compound, iodobutyl triphenylphosphonium (IBTP, decreased mitochondrial metabolism and ATP in MDA-MB 231 (MB231 breast adenocarcinoma cells up to 6 days after an initial 24 h treatment. Mitochondrial thiol modification also depressed oxygen consumption rates (OCR in a dose-dependent manner to a greater extent than a non-thiol modifying analog, suggesting that thiol reactivity is an important factor in the inhibition of cancer cell metabolism. In non-tumorigenic MCF-10A cells, IBTP also decreased OCR; however the extracellular acidification rate was significantly increased at all but the highest concentration (10 µM of IBTP indicating that thiol modification can have significantly different effects on bioenergetics in tumorigenic versus non-tumorigenic cells. ATP and other adenonucleotide levels were also decreased by thiol modification up to 6 days post-treatment, indicating a decreased overall energetic state in MB231 cells. Cellular proliferation of MB231 cells was also inhibited up to 6 days post-treatment with little change to cell viability. Targeted metabolomic analyses revealed that thiol modification caused depletion of both Krebs cycle and glutaminolysis intermediates. Further experiments revealed that the activity of the Krebs cycle enzyme, aconitase, was attenuated in response to thiol modification. Additionally, the inhibition of glutaminolysis corresponded to decreased glutaminase C (GAC protein levels, although other protein levels were

  11. Beyond Cannabis: Plants and the Endocannabinoid System.

    Science.gov (United States)

    Russo, Ethan B

    2016-07-01

    Plants have been the predominant source of medicines throughout the vast majority of human history, and remain so today outside of industrialized societies. One of the most versatile in terms of its phytochemistry is cannabis, whose investigation has led directly to the discovery of a unique and widespread homeostatic physiological regulator, the endocannabinoid system. While it had been the conventional wisdom until recently that only cannabis harbored active agents affecting the endocannabinoid system, in recent decades the search has widened and identified numerous additional plants whose components stimulate, antagonize, or modulate different aspects of this system. These include common foodstuffs, herbs, spices, and more exotic ingredients: kava, chocolate, black pepper, and many others that are examined in this review. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Crosstalk between liver antioxidant and the endocannabinoid systems after chronic administration of the FAAH inhibitor, URB597, to hypertensive rats

    Energy Technology Data Exchange (ETDEWEB)

    Biernacki, Michał; Łuczaj, Wojciech; Gęgotek, Agnieszka [Department of Analytical Chemistry Medical University of Bialystok, Mickiewicza 2D, 15-222 Bialystok (Poland); Toczek, Marek [Department of Experimental Physiology and Pathophysiology Medical University of Bialystok, Mickiewicza 2A, 15-222 Bialystok (Poland); Bielawska, Katarzyna [Department of Analytical Chemistry Medical University of Bialystok, Mickiewicza 2D, 15-222 Bialystok (Poland); Skrzydlewska, Elżbieta, E-mail: elzbieta.skrzydlewska@umb.edu.pl [Department of Analytical Chemistry Medical University of Bialystok, Mickiewicza 2D, 15-222 Bialystok (Poland)

    2016-06-15

    Hypertension is accompanied by perturbations to the endocannabinoid and antioxidant systems. Thus, potential pharmacological treatments for hypertension should be examined as modulators of these two metabolic systems. The aim of this study was to evaluate the effects of chronic administration of the fatty acid amide hydrolase (FAAH) inhibitor [3-(3-carbamoylphenyl)phenyl]N-cyclohexylcarbamate (URB597) on the endocannabinoid system and on the redox balance in the livers of DOCA-salt hypertensive rats. Hypertension caused an increase in the levels of endocannabinoids [anandamide (AEA), 2-arachidonoyl-glycerol (2-AG) and N-arachidonoyl-dopamine (NADA)] and CB{sub 1} receptor and the activities of FAAH and monoacylglycerol lipase (MAGL). These effects were accompanied by an increase in the level of reactive oxygen species (ROS), a decrease in antioxidant activity/level, enhanced expression of transcription factor Nrf2 and changes to Nrf2 activators and inhibitors. Moreover, significant increases in lipid, DNA and protein oxidative modifications, which led to enhanced levels of proapoptotic caspases, were also observed. URB597 administration to the hypertensive rats resulted in additional increases in the levels of AEA, NADA and the CB{sub 1} receptor, as well as decreases in vitamin E and C levels, glutathione peroxidase and glutathione reductase activities and Nrf2 expression. Thus, after URB597 administration, oxidative modifications of cellular components were increased, while the inflammatory response was reduced. This study revealed that chronic treatment of hypertensive rats with URB597 disrupts the endocannabinoid system, which causes an imbalance in redox status. This imbalance increases the levels of electrophilic lipid peroxidation products, which later participate in metabolic disturbances in liver homeostasis. - Highlights: • Chronic administration of URB597 to hypertensive rats reduces liver inflammation. • URB597 enhances the redox imbalance in the

  13. Crosstalk between liver antioxidant and the endocannabinoid systems after chronic administration of the FAAH inhibitor, URB597, to hypertensive rats

    International Nuclear Information System (INIS)

    Biernacki, Michał; Łuczaj, Wojciech; Gęgotek, Agnieszka; Toczek, Marek; Bielawska, Katarzyna; Skrzydlewska, Elżbieta

    2016-01-01

    Hypertension is accompanied by perturbations to the endocannabinoid and antioxidant systems. Thus, potential pharmacological treatments for hypertension should be examined as modulators of these two metabolic systems. The aim of this study was to evaluate the effects of chronic administration of the fatty acid amide hydrolase (FAAH) inhibitor [3-(3-carbamoylphenyl)phenyl]N-cyclohexylcarbamate (URB597) on the endocannabinoid system and on the redox balance in the livers of DOCA-salt hypertensive rats. Hypertension caused an increase in the levels of endocannabinoids [anandamide (AEA), 2-arachidonoyl-glycerol (2-AG) and N-arachidonoyl-dopamine (NADA)] and CB 1 receptor and the activities of FAAH and monoacylglycerol lipase (MAGL). These effects were accompanied by an increase in the level of reactive oxygen species (ROS), a decrease in antioxidant activity/level, enhanced expression of transcription factor Nrf2 and changes to Nrf2 activators and inhibitors. Moreover, significant increases in lipid, DNA and protein oxidative modifications, which led to enhanced levels of proapoptotic caspases, were also observed. URB597 administration to the hypertensive rats resulted in additional increases in the levels of AEA, NADA and the CB 1 receptor, as well as decreases in vitamin E and C levels, glutathione peroxidase and glutathione reductase activities and Nrf2 expression. Thus, after URB597 administration, oxidative modifications of cellular components were increased, while the inflammatory response was reduced. This study revealed that chronic treatment of hypertensive rats with URB597 disrupts the endocannabinoid system, which causes an imbalance in redox status. This imbalance increases the levels of electrophilic lipid peroxidation products, which later participate in metabolic disturbances in liver homeostasis. - Highlights: • Chronic administration of URB597 to hypertensive rats reduces liver inflammation. • URB597 enhances the redox imbalance in the liver of

  14. Comparative effects of parathion and chlorpyrifos on endocannabinoid and endocannabinoid-like lipid metabolites in rat striatum.

    Science.gov (United States)

    Liu, Jing; Parsons, Loren; Pope, Carey

    2015-09-01

    Parathion and chlorpyrifos are organophosphorus insecticides (OPs) that elicit acute toxicity by inhibiting acetylcholinesterase (AChE). The endocannabinoids (eCBs, N-arachidonoylethanolamine, AEA; 2-arachidonoylglycerol, 2AG) are endogenous neuromodulators that regulate presynaptic neurotransmitter release in neurons throughout the central and peripheral nervous systems. While substantial information is known about the eCBs, less is known about a number of endocannabinoid-like metabolites (eCBLs, e.g., N-palmitoylethanolamine, PEA; N-oleoylethanolamine, OEA). We report the comparative effects of parathion and chlorpyrifos on AChE and enzymes responsible for inactivation of the eCBs, fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL), and changes in the eCBs AEA and 2AG and eCBLs PEA and OEA, in rat striatum. Adult, male rats were treated with vehicle (peanut oil, 2 ml/kg, sc), parathion (27 mg/kg) or chlorpyrifos (280 mg/kg) 6-7 days after surgical implantation of microdialysis cannulae into the right striatum, followed by microdialysis two or four days later. Additional rats were similarly treated and sacrificed for evaluation of tissue levels of eCBs and eCBLs. Dialysates and tissue extracts were analyzed by LC-MS/MS. AChE and FAAH were extensively inhibited at both time-points (85-96%), while MAGL activity was significantly but lesser affected (37-62% inhibition) by parathion and chlorpyrifos. Signs of toxicity were noted only in parathion-treated rats. In general, chlorpyrifos increased eCB levels while parathion had no or lesser effects. Early changes in extracellular AEA, 2AG and PEA levels were significantly different between parathion and chlorpyrifos exposures. Differential changes in extracellular and/or tissue levels of eCBs and eCBLs could potentially influence a number of signaling pathways and contribute to selective neurological changes following acute OP intoxications. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Endocannabinoids mediate neuron-astrocyte communication.

    Science.gov (United States)

    Navarrete, Marta; Araque, Alfonso

    2008-03-27

    Cannabinoid receptors play key roles in brain function, and cannabinoid effects in brain physiology and drug-related behavior are thought to be mediated by receptors present in neurons. Neuron-astrocyte communication relies on the expression by astrocytes of neurotransmitter receptors. Yet, the expression of cannabinoid receptors by astrocytes in situ and their involvement in the neuron-astrocyte communication remain largely unknown. We show that hippocampal astrocytes express CB1 receptors that upon activation lead to phospholipase C-dependent Ca2+ mobilization from internal stores. These receptors are activated by endocannabinoids released by neurons, increasing astrocyte Ca2+ levels, which stimulate glutamate release that activates NMDA receptors in pyramidal neurons. These results demonstrate the existence of endocannabinoid-mediated neuron-astrocyte communication, revealing that astrocytes are targets of cannabinoids and might therefore participate in the physiology of cannabinoid-related addiction. They also reveal the existence of an endocannabinoid-glutamate signaling pathway where astrocytes serve as a bridge for nonsynaptic interneuronal communication.

  16. Differential 3-bromopyruvate inhibition of cytosolic and mitochondrial human serine hydroxymethyltransferase isoforms, key enzymes in cancer metabolic reprogramming.

    Science.gov (United States)

    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.

  17. Differences in the endocannabinoid system of sperm from fertile and infertile men.

    Directory of Open Access Journals (Sweden)

    Sheena E M Lewis

    Full Text Available Male infertility is a major cause of problems for many couples in conceiving a child. Recently, lifestyle pastimes such as alcohol, tobacco and marijuana have been shown to have further negative effects on male reproduction. The endocannabinoid system (ECS, mainly through the action of anandamide (AEA and 2-arachidonoylglycerol (2-AG at cannabinoid (CB(1, CB(2 and vanilloid (TRPV1 receptors, plays a crucial role in controlling functionality of sperm, with a clear impact on male reproductive potential. Here, sperm from fertile and infertile men were used to investigate content (through LC-ESI-MS, mRNA (through quantitative RT-PCR, protein (through Western Blotting and ELISA expression, and functionality (through activity and binding assays of the main metabolic enzymes of AEA and 2-AG (NAPE-PLD and FAAH, for AEA; DAGL and MAGL for 2-AG, as well as of their binding receptors CB(1, CB(2 and TRPV1. Our findings show a marked reduction of AEA and 2-AG content in infertile seminal plasma, paralleled by increased degradation: biosynthesis ratios of both substances in sperm from infertile versus fertile men. In addition, TRPV1 binding was detected in fertile sperm but was undetectable in infertile sperm, whereas that of CB(1 and CB(2 receptors was not statistically different in the two groups. In conclusion, this study identified unprecedented alterations of the ECS in infertile sperm, that might impact on capacitation and acrosome reaction, and hence fertilization outcomes. These alterations might also point to new biomarkers to determine male reproductive defects, and identify distinct ECS elements as novel targets for therapeutic exploitation of ECS-oriented drugs to treat male fertility problems.

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

    Science.gov (United States)

    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

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

    Directory of Open Access Journals (Sweden)

    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.

  20. [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.

  1. Investigation on the Metabolic Regulation of pgi gene knockout Escherichia coli by Enzyme Activities and Intracellular Metabolite Concentrations

    Directory of Open Access Journals (Sweden)

    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.

  2. Motion sickness, stress and the endocannabinoid system.

    Directory of Open Access Journals (Sweden)

    Alexander Choukèr

    Full Text Available BACKGROUND: A substantial number of individuals are at risk for the development of motion sickness induced nausea and vomiting (N&V during road, air or sea travel. Motion sickness can be extremely stressful but the neurobiologic mechanisms leading to motion sickness are not clear. The endocannabinoid system (ECS represents an important neuromodulator of stress and N&V. Inhibitory effects of the ECS on N&V are mediated by endocannabinoid-receptor activation. METHODOLOGY/PRINCIPAL FINDINGS: We studied the activity of the ECS in human volunteers (n = 21 during parabolic flight maneuvers (PFs. During PFs, microgravity conditions (<10(-2 g are generated for approximately 22 s which results in a profound kinetic stimulus. Blood endocannabinoids (anandamide and 2-arachidonoylglycerol, 2-AG were measured from blood samples taken in-flight before start of the parabolic maneuvers, after 10, 20, and 30 parabolas, in-flight after termination of PFs and 24 h later. Volunteers who developed acute motion sickness (n = 7 showed significantly higher stress scores but lower endocannabinoid levels during PFs. After 20 parabolas, blood anandamide levels had dropped significantly in volunteers with motion sickness (from 0.39+/-0.40 to 0.22+/-0.25 ng/ml but increased in participants without the condition (from 0.43+/-0.23 to 0.60+/-0.38 ng/ml resulting in significantly higher anandamide levels in participants without motion sickness (p = 0.02. 2-AG levels in individuals with motion sickness were low and almost unchanged throughout the experiment but showed a robust increase in participants without motion sickness. Cannabinoid-receptor 1 (CB1 but not cannabinoid-receptor 2 (CB2 mRNA expression in leucocytes 4 h after the experiment was significantly lower in volunteers with motion sickness than in participants without N&V. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate that stress and motion sickness in humans are associated with impaired endocannabinoid

  3. Effect of aspirin and prostaglandins on the carbohydrate metabolism in albino rats.: glucose oxidation through different pathways and glycolytic enzymes

    International Nuclear Information System (INIS)

    Balasubramanian, A.; Ramakrishnan, S.

    1980-01-01

    The effect of chronic and acute doses of aspirin and prostaglandins F2α and E2 individually on the oxidation of glucose through Embden Meyerhof-TCA cycle and pentose phosphate pathways and some key glycolytic enzymes of liver were studied in male albino rats. Studies were extended to find the combined effect of PGF2α and E2 with an acute dose of aspirin. There was increased utilisation of both 1- 14 C glucose and 6- 14 C glucose on aspirin treatment. However, the metabolism through the EM-TCA pathway was more pronounced as shown by a reduced ratio of 14 CO 2 from 1- 14 C and 6- 14 C glucose. Two hepatic key glycolytic enzymes viz. hexokinase and pyruvate kinase were increased due to aspirin treatment. Withdrawal of aspirin corrected the above impaired carbohydrate metabolism in liver. Prostaglandin F2α also caused a reduction in the utilisation of 1- 14 C glucose, while PGE2 recorded an increase in the utilisation of both 1- 14 C and 6- 14 C glucose when compared to controls, indicating that different members of prostaglandins could affect metabolisms and differently. Administration of the PGs and aspirin together showed an increase in the utilisation of 6- 14 C glucose. (auth.)

  4. Controlled sumoylation of the mevalonate pathway enzyme HMGS-1 regulates metabolism during aging

    NARCIS (Netherlands)

    Sapir, Amir; Tsur, Assaf; Koorman, Thijs; Ching, Kaitlin; Mishra, Prashant; Bardenheier, Annabelle; Podolsky, Lisa; Bening-Abu-Shach, Ulrike; Boxem, Mike; Chou, Tsui-Fen; Broday, Limor; Sternberg, Paul W

    2014-01-01

    Many metabolic pathways are critically regulated during development and aging but little is known about the molecular mechanisms underlying this regulation. One key metabolic cascade in eukaryotes is the mevalonate pathway. It catalyzes the synthesis of sterol and nonsterol isoprenoids, such as

  5. 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...

  6. Differential effects of dietary flavonoids on drug metabolizing and antioxidant enzymes in female rat

    DEFF Research Database (Denmark)

    Breinholt, V.; Lauridsen, S.T.; Dragsted, L.O.

    1999-01-01

    1. Gavage administration of the natural flavonoids tangeretin, chrysin, apigenin, naringenin, genistein and quercetin for 2 consecutive weeks to the female rat resulted in differential effects on selected phase 1 and 2 enzymes in liver, colon and heart as well as antioxidant enzymes in red brood......) significantly protected against, 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine (PhIP)-induced oxidative stress. Hepatic PhIP-DNA adduct formation was not affected by any of the administered flavonoids, whereas PhIP-DNA adduct formation in colon was slightly, but significantly, inhibited by quercetin......, genistein, tangeretin and BNF. 5. The observed effects of chrysin, quercetin and genistein on antioxidant enzymes, concurrently with a protection against oxidative stress, suggest a feedback mechanism on the antioxidant enzymes triggered by the flavonoid antioxidants. 6. Despite the use of high flavonoid...

  7. Metabolic control by sirtuins and other enzymes that sense NAD(+), NADH, or their ratio

    DEFF Research Database (Denmark)

    Anderson, Kristin A; Madsen, Andreas S; Olsen, Christian A

    2017-01-01

    NAD(+) is a dinucleotide cofactor with the potential to accept electrons in a variety of cellular reduction-oxidation (redox) reactions. In its reduced form, NADH is a ubiquitous cellular electron donor. NAD(+), NADH, and the NAD(+)/NADH ratio have long been known to control the activity of several...... oxidoreductase enzymes. More recently, enzymes outside those participating directly in redox control have been identified that sense these dinucleotides, including the sirtuin family of NAD(+)-dependent protein deacylases. In this review, we highlight examples of non-redox enzymes that are controlled by NAD......(+), NADH, or NAD(+)/NADH. In particular, we focus on the sirtuin family and assess the current evidence that the sirtuin enzymes sense these dinucleotides and discuss the biological conditions under which this might occur; we conclude that sirtuins sense NAD(+), but neither NADH nor the ratio. Finally, we...

  8. Oxidative drug metabolizing enzymes in North Sea dab (Limanda limanda). Biological effects of pollutants

    International Nuclear Information System (INIS)

    Vobach, M.; Kellermann, H.J.

    1999-01-01

    Increasing environmental pollution is regarded as an anthropogenic stress factor in general. As a consequence, this may have several detrimental impacts on organisms, including aquatic species. The ability of organisms to tolerate stress from chemical pollutants depends on the availability of a variety of protection mechanisms. One important mechanism to protect cells from lipophilic xenobiotics is based on enzymes or enzyme systems converting the chemicals into more polar metabolites which can be excreted

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

    OpenAIRE

    Meyer, Pablo; Cecchi, Guillermo; Stolovitzky, Gustavo

    2014-01-01

    Background 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. Results 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 ...

  10. Endocannabinoids and the Cardiovascular System in Health and Disease.

    Science.gov (United States)

    O'Sullivan, Saoirse Elizabeth

    2015-01-01

    The endocannabinoid system is widely distributed throughout the cardiovascular system. Endocannabinoids play a minimal role in the regulation of cardiovascular function in normal conditions, but are altered in most cardiovascular disorders. In shock, endocannabinoids released within blood mediate the associated hypotension through CB(1) activation. In hypertension, there is evidence for changes in the expression of CB(1), and CB(1) antagonism reduces blood pressure in obese hypertensive and diabetic patients. The endocannabinoid system is also upregulated in cardiac pathologies. This is likely to be cardioprotective, via CB(2) and CB(1) (lesser extent). In the vasculature, endocannabinoids cause vasorelaxation through activation of multiple target sites, inhibition of calcium channels, activation of potassium channels, NO production and the release of vasoactive substances. Changes in the expression or function of any of these pathways alter the vascular effect of endocannabinoids. Endocannabinoids have positive (CB(2)) and negative effects (CB(1)) on the progression of atherosclerosis. However, any negative effects of CB(1) may not be consequential, as chronic CB(1) antagonism in large scale human trials was not associated with significant reductions in atheroma. In neurovascular disorders such as stroke, endocannabinoids are upregulated and protective, involving activation of CB(1), CB(2), TRPV1 and PPARα. Although most of this evidence is from preclinical studies, it seems likely that cannabinoid-based therapies could be beneficial in a range of cardiovascular disorders.

  11. Effect of high dietary copper on growth, antioxidant and lipid metabolism enzymes of juvenile larger yellow croaker Larimichthys croceus

    Directory of Open Access Journals (Sweden)

    Fanxing Meng

    2016-05-01

    Full Text Available A study was carried out to test the responses of juvenile larger yellow croaker Larimichthys croceus to high Cu intake. Experimental diets were formulated containing three levels of Cu: low Cu (3.67 mg/kg, middle Cu (13.65 mg/kg and high Cu (25.78 mg/kg, and each diet were fed to large yellow croaker in triplicate for 10 weeks. Final body weight, weight gain and feed intake were the lowest in high Cu group, but hepatosomatic index was the highest; Cu concentrations in the whole-body, muscle and liver of fish fed low Cu diet was the lowest; Liver superoxide dismutase, catalase and glutathione peroxidase activities in fish fed high Cu diet were lower than those in fish fed other diets; The higher content of liver thiobarbituric acid reactive substance content was found in high Cu group, followed by middle Cu group, and the lowest in low Cu group; Liver 6-phosphogluconate dehydrogenase, glucose-6-phosphate dehydrogenase, malic enzyme, isocitrate dehydrogenase and fatty acid synthase activities were the lowest in high Cu group, but lipoprotein lipase activity was the highest. This study indicated that high copper intake reduced growth of juvenile larger yellow croaker, inhibited activities of antioxidant enzymes and lipid synthetases, and led to energy mobilization. Keywords: Larger yellow croaker, Copper, Antioxidant enzyme, Lipid metabolism enzyme

  12. 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.

  13. Assessment of mercaptopurine (6MP) metabolites and 6MP metabolic key-enzymes in childhood acute lymphoblastic leukemia.

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  16. 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.

  17. From Fertilisation to Implantation in Mammalian Pregnancy—Modulation of Early Human Reproduction by the Endocannabinoid System

    Directory of Open Access Journals (Sweden)

    Justin C. Konje

    2010-09-01

    Full Text Available There is an increasing recognition that the endocannabinoid system is the crucial cytokine-hormone system regulating early human pregnancy. The synchronous development of the fertilized embryo and the endometrium to ensure timely implantation has been shown to be one of the pivotal steps to successful implantation. This development is thought to be regulated by a finely balanced relationship between various components of the endocannabinoid system in the endometrium, the embryo and the Fallopian tube. In addition, this system has also been shown to be involved in the regulation of the development and maturation of the gametes prior to fertilization. In this review, we will examine the evidence from animal and human studies to support the role of the endocannabinoid system in gametogenesis, fertilization, implantation, early pregnancy maintenance, and in immunomodulation of pregnancy. We will discuss the role of the cannabinoid receptors and the enzymes involved in the synthesis and degradation of the key endocannabinoid ligands (e.g., anandamide and 2-arachinoylglycerol in early reproduction.

  18. Polyphenols of Salix aegyptiaca modulate the activities of drug metabolizing and antioxidant enzymes, and level of lipid peroxidation.

    Science.gov (United States)

    Nauman, Mohd; Kale, R K; Singh, Rana P

    2018-03-07

    Salix aegyptiaca is known for its medicinal properties mainly due to the presence of salicylate compounds. However, it also contains other beneficial phytochemicals such as gallic acid, quercetin, rutin and vanillin. The aim of the study was to examine the redox potential, antioxidant and anti-inflammatory activity of these phytochemicals along with acetylsalicylic acid. The redox potential and antioxidant activity of gallic acid, quercetin, rutin, vanillin and acetylsalicylic acid were determined by oxidation-reduction potential electrode method and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, respectively. In ex vivo studies, antioxidant activity of these phytochemicals was determined by lipid peroxidation and carbonyl content assay in the liver of mice. Anti-inflammatory activity was determined by protein denaturation method. Six-week old C57BL/6 mice treated with gallic acid (100 mg/kg body weight) and acetylsalicylic acid (25 and 50 mg/kg body weight) to investigate their in vivo modulatory effects on the specific activities of drug metabolizing phase I and phase II enzymes, antioxidant enzymes and level of lipid peroxidation in liver. The order of ability to donate electron and antioxidant activity was found to be: gallic acid > quercetin > rutin > vanillin > acetylsalicylic acid. In ex vivo studies, the similar pattern and magnitude of inhibitory effects of these phytochemicals against peroxidative damage in microsomes and protein carbonyl in cytosolic fraction were observed. In in vivo studies, gallic acid and acetylsalicylic acid alone or in combination, enhanced the specific activities of drug metabolizing phase I and phase II enzymes as well as antioxidant enzymes and also inhibited lipid peroxidation in liver. These findings show a close link between the electron donation and antioxidation potential of these phytochemicals, and in turn their biological activity. Gallic acid, quercetin, rutin and vanillin were found to be better electron donors and

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

    Science.gov (United States)

    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.

  20. DEVELOPING OF INSTRUCTIONAL MEDIA-BASED ANIMATION VIDEO ON ENZYME AND METABOLISM MATERIAL IN SENIOR HIGH SCHOOL

    Directory of Open Access Journals (Sweden)

    Muhammad Mustofa Yusuf

    2017-11-01

    Full Text Available The research aimed to product a learning material related to animation video on enzyme and metabolism material for high school student which is validated by media and material experts, educational practition and student legibility. Research and development model is ADDIE with quantitative-qualitative data analyzing methode. Data collection was obtained from validation results by media and material experts, educational partition and student legibility. The validation results were scores and suggestion. The percentage of product from expert media validation (100%, expert material validation (89,58%, educational practition (84,61%, and student legibility (81,91% showed valid of the criteria and feasible to use after revision.

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

    Science.gov (United States)

    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

  2. DrugMetZ DB: an anthology of human drug metabolizing Chytochrome P450 enzymes.

    Science.gov (United States)

    Antony, Tresa Remya Thomas; Nagarajan, Shanthi

    2006-11-14

    Understandings the basics of Cytochrome P450 (P450 or CYP) will help to discern drug metabolism. CYP, a super-family of heme-thiolate proteins, are found in almost all living organisms and is involved in the biotransformation of a diverse range of xenobiotics, therapeutic drugs and toxins. Here, we describe DrugMetZ DB, a database for CYP metabolizing drugs. The DB is implemented in MySQL, PHP and HTML. www.bicpu.edu.in/DrugMetZDB/

  3. Enzyme chemistry and the evolution of metabolic diversity: the β-ketoadipate pathway

    International Nuclear Information System (INIS)

    Kozarich, J.W.

    1986-01-01

    The two converging catechol and protocatechuate branches of the β-ketoadipate pathway in Pseudomonas putida have long been considered a paradigm of evolutionary divergence of specialized enzymes from a common ancestor. The structural similarities of substrates, products and the enzymes themselves have supported this hypothesis. Employing chemical and 1 H NMR techniques, they have determined the absolute stereochemical courses of the reactions catalyzed by β-carboxymuconate cycloisomerase, muconolactone isomerase, and γ-carboxymuconolactone decarboxylase. Surprisingly, β-carboxymuconate cycloisomerase proceeds via an anti addition while the corresponding muconate cycloisomerase has been shown to catalyze a syn addition. Moreover, the chiral centers generated in the products of both enzymes are of the opposite relative configuration. They believe that the shift in mechanism may reflect basic energetic differences of the two reactions. The stereochemistries of the isomerase and decarboxylase have been established by 1 H NMR using a ricochet analysis. Both reactions proceed via a syn process; the relative configurations of muconolactone and γ-carboxymuconolactone necessitate that the enzymes operate on opposite faces of the common enol-lactone product. These findings suggest that either critical active site changes have occurred in these enzymes to accommodate preferred mechanistic pathways or the evolutionary relationship of the two branches is more remote than previously believed

  4. Metabolic control by sirtuins and other enzymes that sense NAD+, NADH, or their ratio.

    Science.gov (United States)

    Anderson, Kristin A; Madsen, Andreas S; Olsen, Christian A; Hirschey, Matthew D

    2017-12-01

    NAD + is a dinucleotide cofactor with the potential to accept electrons in a variety of cellular reduction-oxidation (redox) reactions. In its reduced form, NADH is a ubiquitous cellular electron donor. NAD + , NADH, and the NAD + /NADH ratio have long been known to control the activity of several oxidoreductase enzymes. More recently, enzymes outside those participating directly in redox control have been identified that sense these dinucleotides, including the sirtuin family of NAD + -dependent protein deacylases. In this review, we highlight examples of non-redox enzymes that are controlled by NAD + , NADH, or NAD + /NADH. In particular, we focus on the sirtuin family and assess the current evidence that the sirtuin enzymes sense these dinucleotides and discuss the biological conditions under which this might occur; we conclude that sirtuins sense NAD + , but neither NADH nor the ratio. Finally, we identify future studies that might be informative to further interrogate physiological and pathophysiological changes in NAD + and NADH, as well as enzymes like sirtuins that sense and respond to redox changes in the cell. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Effect of Various Diets on the Expression of Phase-I Drug Metabolizing Enzymes in Livers of Mice

    Science.gov (United States)

    Guo, Ying; Cui, Julia Yue; Lu, Hong; Klaassen, Curtis D.

    2017-01-01

    Previous studies have shown that diets can alter the metabolism of drugs; however, it is difficult to compare the effects of multiple diets on drug metabolism among different experimental settings. Phase-I related genes play a major role in the biotransformation of pro-drugs and drugs.In the current study, effects of nine diets on the mRNA expression of phase-I drug-metabolizing enzymes in livers of mice were simultaneously investigated. Compared to the AIN-93M purified diet (control), 73 of the 132 critical phase-I drug metabolizing genes were differentially regulated by at least one diet. Diet restriction produced the most number of changed genes (51), followed by the atherogenic diet (27), high-fat diet (25), standard rodent chow (21), western diet (20), high-fructose diet (5), EFA deficient diet (3), and low n-3 FA diet (1). The mRNAs of the Fmo family changed most, followed by Cyp2b and 4a subfamilies, as well as Por (From 1121 to 21-fold increase of theses mRNAs). There were 59 genes not altered by any of these diets.The present results may improve the interpretation of studies with mice and aid in determining effective and safe doses for individuals with different nutritional diets. PMID:25733028

  6. Phase I to II cross-induction of xenobiotic metabolizing enzymes: A feedforward control mechanism for potential hormetic responses

    International Nuclear Information System (INIS)

    Zhang Qiang; Pi Jingbo; Woods, Courtney G.; Andersen, Melvin E.

    2009-01-01

    Hormetic responses to xenobiotic exposure likely occur as a result of overcompensation by the homeostatic control systems operating in biological organisms. However, the mechanisms underlying overcompensation that leads to hormesis are still unclear. A well-known homeostatic circuit in the cell is the gene induction network comprising phase I, II and III metabolizing enzymes, which are responsible for xenobiotic detoxification, and in many cases, bioactivation. By formulating a differential equation-based computational model, we investigated in this study whether hormesis can arise from the operation of this gene/enzyme network. The model consists of two feedback and one feedforward controls. With the phase I negative feedback control, xenobiotic X activates nuclear receptors to induce cytochrome P450 enzyme, which bioactivates X into a reactive metabolite X'. With the phase II negative feedback control, X' activates transcription factor Nrf2 to induce phase II enzymes such as glutathione S-transferase and glutamate cysteine ligase, etc., which participate in a set of reactions that lead to the metabolism of X' into a less toxic conjugate X''. The feedforward control involves phase I to II cross-induction, in which the parent chemical X can also induce phase II enzymes directly through the nuclear receptor and indirectly through transcriptionally upregulating Nrf2. As a result of the active feedforward control, a steady-state hormetic relationship readily arises between the concentrations of the reactive metabolite X' and the extracellular parent chemical X to which the cell is exposed. The shape of dose-response evolves over time from initially monotonically increasing to J-shaped at the final steady state-a temporal sequence consistent with adaptation-mediated hormesis. The magnitude of the hormetic response is enhanced by increases in the feedforward gain, but attenuated by increases in the bioactivation or phase II feedback loop gains. Our study suggests a

  7. Phase I to II cross-induction of xenobiotic metabolizing enzymes: a feedforward control mechanism for potential hormetic responses.

    Science.gov (United States)

    Zhang, Qiang; Pi, Jingbo; Woods, Courtney G; Andersen, Melvin E

    2009-06-15

    Hormetic responses to xenobiotic exposure likely occur as a result of overcompensation by the homeostatic control systems operating in biological organisms. However, the mechanisms underlying overcompensation that leads to hormesis are still unclear. A well-known homeostatic circuit in the cell is the gene induction network comprising phase I, II and III metabolizing enzymes, which are responsible for xenobiotic detoxification, and in many cases, bioactivation. By formulating a differential equation-based computational model, we investigated in this study whether hormesis can arise from the operation of this gene/enzyme network. The model consists of two feedback and one feedforward controls. With the phase I negative feedback control, xenobiotic X activates nuclear receptors to induce cytochrome P450 enzyme, which bioactivates X into a reactive metabolite X'. With the phase II negative feedback control, X' activates transcription factor Nrf2 to induce phase II enzymes such as glutathione S-transferase and glutamate cysteine ligase, etc., which participate in a set of reactions that lead to the metabolism of X' into a less toxic conjugate X''. The feedforward control involves phase I to II cross-induction, in which the parent chemical X can also induce phase II enzymes directly through the nuclear receptor and indirectly through transcriptionally upregulating Nrf2. As a result of the active feedforward control, a steady-state hormetic relationship readily arises between the concentrations of the reactive metabolite X' and the extracellular parent chemical X to which the cell is exposed. The shape of dose-response evolves over time from initially monotonically increasing to J-shaped at the final steady state-a temporal sequence consistent with adaptation-mediated hormesis. The magnitude of the hormetic response is enhanced by increases in the feedforward gain, but attenuated by increases in the bioactivation or phase II feedback loop gains. Our study suggests a

  8. Natural variations in xenobiotic-metabolizing enzymes: developing tools for coral monitoring

    Science.gov (United States)

    Rougée, L. R. A.; Richmond, R. H.; Collier, A. C.

    2014-06-01

    The continued deterioration of coral reefs worldwide demonstrates the need to develop diagnostic tools for corals that go beyond general ecological monitoring and can identify specific stressors at sublethal levels. Cellular diagnostics present an approach to defining indicators (biomarkers) that have the potential to reflect the impact of stress at the cellular level, allowing for the detection of intracellular changes in corals prior to outright mortality. Detoxification enzymes, which may be readily induced or inhibited by environmental stressors, present such a set of indicators. However, in order to apply these diagnostic tools for the detection of stress, a detailed understanding of their normal, homeostatic levels within healthy corals must first be established. Herein, we present molecular and biochemical evidence for the expression and activity of major Phase I detoxification enzymes cytochrome P450 (CYP450), CYP2E1, and CYP450 reductase, as well as the Phase II enzymes UDP, glucuronosyltransferase (UGT), β-glucuronidase, glutathione- S-transferase (GST), and arylsulfatase C (ASC) in the coral Pocillopora damicornis. Additionally, we characterized enzyme expression and activity variations over a reproductive cycle within a coral's life history to determine natural endogenous changes devoid of stress exposure. Significant changes in enzyme activity over the coral's natural lunar reproductive cycle were observed for CYP2E1 and CYP450 reductase as well as UGT and GST, while β-glucuronidase and ASC did not fluctuate significantly. The data represent a baseline description of `health' for the expression and activity of these enzymes that can be used toward understanding the impact of environmental stressors on corals. Such knowledge can be applied to address causes of coral reef ecosystem decline and to monitor effectiveness of mitigation strategies. Achieving a better understanding of cause-and-effect relationships between putative stressors and biological

  9. 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.

  10. Changes in element accumulation, phenolic metabolism, and antioxidative enzyme activities in the red-skin roots of Panax ginseng.

    Science.gov (United States)

    Zhou, Ying; Yang, Zhenming; Gao, Lingling; Liu, Wen; Liu, Rongkun; Zhao, Junting; You, Jiangfeng

    2017-07-01

    Red-skin root disease has seriously decreased the quality and production of Panax ginseng (ginseng). To explore the disease's origin, comparative analysis was performed in different parts of the plant, particularly the epidermis, cortex, and/or fibrous roots of 5-yr-old healthy and diseased red-skin ginseng. The inorganic element composition, phenolic compound concentration, reactive oxidation system, antioxidant concentrations such as ascorbate and glutathione, activities of enzymes related to phenolic metabolism and oxidation, and antioxidative system particularly the ascorbate-glutathione cycle were examined using conventional methods. Aluminum (Al), iron (Fe), magnesium, and phosphorus were increased, whereas manganese was unchanged and calcium was decreased in the epidermis and fibrous root of red-skin ginseng, which also contained higher levels of phenolic compounds, higher activities of the phenolic compound-synthesizing enzyme phenylalanine ammonia-lyase and the phenolic compound oxidation-related enzymes guaiacol peroxidase and polyphenoloxidase. As the substrate of guaiacol peroxidase, higher levels of H 2 O 2 and correspondingly higher activities of superoxide dismutase and catalase were found in red-skin ginseng. Increased levels of ascorbate and glutathione; increased activities of l-galactose 1-dehydrogenase, ascorbate peroxidase, ascorbic acid oxidase, and glutathione reductase; and lower activities of dehydroascorbate reductase, monodehydroascorbate reductase, and glutathione peroxidase were found in red-skin ginseng. Glutathione- S -transferase activity remained constant. Hence, higher element accumulation, particularly Al and Fe, activated multiple enzymes related to accumulation of phenolic compounds and their oxidation. This might contribute to red-skin symptoms in ginseng. It is proposed that antioxidant and antioxidative enzymes, especially those involved in ascorbate-glutathione cycles, are activated to protect against phenolic compound

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

    Science.gov (United States)

    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.

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

    Czech Academy of Sciences Publication Activity Database

    Convigton, E. D.; Roitsch, Thomas; Dernastia, M.

    2016-01-01

    Roč. 63, č. 4 (2016), s. 757-762 ISSN 1318-0207 R&D Projects: GA MŠk(CZ) LO1415 Institutional support: RVO:67179843 Keywords : AGPase * carbohydrates * invertases * sucrose synthase * panel of enzyme activity assays * phytoplasma Subject RIV: EH - Ecology, Behaviour Impact factor: 0.983, year: 2016

  13. Stereoselectivity of the distribution of labelled noradrenaline in rabbit aortic strips after inhibition of the noradrenaline-metabolizing enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Eckert, E; Henseling, M; Gescher, A; Trendelenburg, U [Wuerzburg Univ. (Germany, F.R.). Inst. fuer Pharmakologie und Toxikologie

    1976-01-01

    Rabbit aortic strips (nerve-free, reserpinepretreated or normal) whose noradrenaline-metabolizing enzymes were inhibited (by in vitro treatment with 0.5 mM pargyline for 30 min and by the presence of 0.1 mM U-0521) were exposed to 1.18 ..mu..M labelled (-)- or (+)noradrenaline for 30 min. At the end of the incubation period some strips were used for analysis of radioactivity (i.e., of noradrenaline and its metabolites), while for others the efflux of radioactivity was determined during 250 min of washout with amine-free solution. An estimate of the original distribution of the amine into the various extraneuronal and neuronal compartments of the tissue was obtained by compartmental analysis of the efflux curves. The mechanisms responsible for the accumulation of radioactivity in extraneuronal and axoplasmic compartments lack stereoselectivity; the rate constants for the efflux of radioactivity from these compartments are the same for (-)- and (+)noradrenaline. Despite the use of enzyme inhibitors, the 'late neuronal efflux' of radioactivity (i.e., the efflux collected between the 200th and 250th min of wash out) contained a considerable proportion of metabolites of noradrenaline. The metabolism of noradrenaline was stereoselective: while dihydroxyphenylglycol (DOPEG) was the predominant metabolite in the efflux from strips incubated with (-)noradrenaline, a considerable part of the efflux from strips incubated with the (+)isomer consisted of dihydroxymandelic acid and 'O-methylated and deaminated' metabolites (in addition to DOPEG).

  14. Xenobiotic-metabolizing enzymes in plants and their role in uptake and biotransformation of veterinary drugs in the environment.

    Science.gov (United States)

    Bártíková, Hana; Skálová, Lenka; Stuchlíková, Lucie; Vokřál, Ivan; Vaněk, Tomáš; Podlipná, Radka

    2015-08-01

    Many various xenobiotics permanently enter plants and represent potential danger for their organism. For that reason, plants have evolved extremely sophisticated detoxification systems including a battery of xenobiotic-metabolizing enzymes. Some of them are similar to those in humans and animals, but there are several plant-specific ones. This review briefly introduces xenobiotic-metabolizing enzymes in plants and summarizes present information about their action toward veterinary drugs. Veterinary drugs are used worldwide to treat diseases and protect animal health. However, veterinary drugs are also unwantedly introduced into environment mostly via animal excrements, they persist in the environment for a long time and may impact on the non-target organisms. Plants are able to uptake, transform the veterinary drugs to non- or less-toxic compounds and store them in the vacuoles and cell walls. This ability may protect not only plant themselves but also other organisms, predominantly invertebrates and wild herbivores. The aim of this review is to emphasize the importance of plants in detoxification of veterinary drugs in the environment. The results of studies, which dealt with transport and biotransformation of veterinary drugs in plants, are summarized and evaluated. In conclusion, the risks and consequences of veterinary drugs in the environment and the possibilities of phytoremediation technologies are considered and future perspectives are outlined.

  15. Stereoselectivity of the distribution of labelled noradrenaline in rabbit aortic strips after inhibition of the noradrenaline-metabolizing enzymes

    International Nuclear Information System (INIS)

    Eckert, E.; Henseling, M.; Gescher, A.; Trendelenburg, U.

    1976-01-01

    Rabbit aortic strips (nerve-free, reserpinepretreated or normal) whose noradrenaline-metabolizing enzymes were inhibited (by in vitro treatment with 0.5 mM pargyline for 30 min and by the presence of 0.1 mM U-0521) were exposed to 1.18 μM labelled (-)- or (+)noradrenaline for 30 min. At the end of the incubation period some strips were used for analysis of radioactivity (i.e., of noradrenaline and its metabolites), while for others the efflux of radioactivity was determined during 250 min of washout with amine-free solution. An estimate of the original distribution of the amine into the various extraneuronal and neuronal compartments of the tissue was obtained by compartmental analysis of the efflux curves. The mechanisms responsible for the accumulation of radioactivity in extraneuronal and axoplasmic compartments lack stereoselectivity; the rate constants for the efflux of radioactivity from these compartments are the same for (-)- and (+)noradrenaline. Despite the use of enzyme inhibitors, the 'late neuronal efflux' of radioactivity (i.e., the efflux collected between the 200th and 250th min of wash out) contained a considerable proportion of metabolites of noradrenaline. The metabolism of noradrenaline was stereoselective: while dihydroxyphenylglycol (DOPEG) was the predominant metabolite in the efflux from strips incubated with (-)noradrenaline, a considerable part of the efflux from strips incubated with the (+)isomer consisted of dihydroxymandelic acid and 'O-methylated and deaminated' metabolites (in addition to DOPEG). (orig/GSE) [de

  16. Iminosugar inhibitors of carbohydrate-active enzymes that underpin cereal grain germination and endosperm metabolism

    DEFF Research Database (Denmark)

    Andriotis, Vasilios M. E.; Rejzek, Martin; Rugen, Michael D.

    2016-01-01

    limited knowledge about the nature and control of starch degradation in plants. Increased societal and commercial demand for enhanced yield and quality in starch crops requires a better understanding of starch metabolism as a whole. Here we review recent advances in understanding the roles of carbohydrate...... the properties and uses of cereal grains, it is possible that starch degradation may be amenable to manipulation through genetic or chemical intervention at the level of cell wall metabolism, rather than simply in the starch degradation pathway per se....

  17. [Effects of berberine on the recovery of rat liver xenobiotic-metabolizing enzymes after partial hepatectomy].

    Science.gov (United States)

    Zverinsky, I V; Zverinskaya, H G; Sutsko, I P; Telegin, P G; Shlyahtun, A G

    2015-01-01

    We have studied the effect of berberine on the recovery processes of liver xenobiotic-metabolizing function during its compensatory growth after 70% partial hepatectomy. It was found the hepatic ability to metabolize foreign substances are not restored up to day 8. Administration of berberine (10 mg/kg intraperitoneally) for 6 days led to normalization of both cytochrome P450-dependent and flavin-containing monooxygenases. It is suggested that in the biotransformation of berberine involved not only cytochrome P450, but also flavin-containing monooxygenases.

  18. TM6SF2 and MAC30, new enzyme homologues in sterol metabolism and common metabolic disease.

    Directory of Open Access Journals (Sweden)

    Luis eSanchez-Pulido

    2014-12-01

    Full Text Available Carriers of the Glu167Lys coding variant in the TM6SF2 gene have recently been identified as being more susceptible to non-alcoholic fatty liver disease (NAFLD, yet exhibit lower levels of circulating lipids and hence are protected against cardiovascular disease. Despite the physiological importance of these observations, the molecular function of TM6SF2 remains unknown, and no sequence similarity with functionally characterised proteins has been identified. In order to trace its evolutionary history and to identify functional domains, we embarked on a computational protein sequence analysis of TM6SF2. We identified a new domain, the EXPERA domain, which is conserved among TM6SF, MAC30/TMEM97 and EBP (D8,D7 sterol isomerase protein families. EBP mutations are the cause of chondrodysplasia punctata 2 X-linked dominant (CDPX2, also known as Conradi-Hünermann-Happle syndrome, a defective cholesterol biosynthesis disorder. Our analysis of evolutionary conservation among EXPERA domain-containing families and the previously suggested catalytic mechanism for the EBP enzyme, indicate that TM6SF and MAC30/TMEM97 families are both highly likely to possess, as for the EBP family, catalytic activity as sterol isomerases. This unexpected prediction of enzymatic functions for TM6SF and MAC30/TMEM97 is important because it now permits detailed experiments to investigate the function of these key proteins in various human pathologies, from cardiovascular disease to cancer.

  19. Decarboxylation of Malate in the Crassulacean Acid Metabolism Plant Bryophyllum (Kalanchoe) fedtschenkoi (Role of NAD-Malic Enzyme).

    Science.gov (United States)

    Cook, R. M.; Lindsay, J. G.; Wilkins, M. B.; Nimmo, H. G.

    1995-01-01

    The role of NAD-malic enzyme (NAD-ME) in the Crassulacean acid metabolism plant Bryophyllum (Kalanchoe) fedtschenkoi was investigated using preparations of intact and solubilized mitochondria from fully expanded leaves. Intact, coupled mitochondria isolated during the day or night did not differ in their ability to take up [14C]malic acid from the surrounding medium or to respire using malate or succinate as substrate. However, intact mitochondria isolated from plants during the day decarboxylated added malate to pyruvate significantly faster than mitochondria isolated from plants at night. NAD-ME activity in solubilized mitochondrial extracts showed hysteretic kinetics and was stimulated by a number of activators, including acetyl-coenzyme A, fructose-1,6-bisphosphate, and sulfate ions. In the absence of these effectors, reaction progress curves were nonlinear, with a pronounced acceleration phase. The lag period before a steady-state rate was reached in assays of mitochondrial extracts decreased during the photoperiod and increased slowly during the period of darkness. However, these changes in the kinetic properties of the enzyme could not account for the changes in the rate of decarboxylation of malate by intact mitochondria. Gel-filtration experiments showed that mitochondrial extracts contained three forms of NAD-ME with different molecular weights. The relative proportions of the three forms varied somewhat throughout the light/dark cycle, but this did not account for the changes in the kinetics behavior of the enzyme during the diurnal cycle. PMID:12228671

  20. Compounds from Terminalia mantaly L. (Combretaceae Stem Bark Exhibit Potent Inhibition against Some Pathogenic Yeasts and Enzymes of Metabolic Significance

    Directory of Open Access Journals (Sweden)

    Marthe Aimée Tchuente Tchuenmogne

    2017-01-01

    Full Text Available Background: Pathogenic yeasts resistance to current drugs emphasizes the need for new, safe, and cost-effective drugs. Also, new inhibitors are needed to control the effects of enzymes that are implicated in metabolic dysfunctions such as cancer, obesity, and epilepsy. Methods: The anti-yeast extract from Terminalia mantaly (Combretaceae was fractionated and the structures of the isolated compounds established by means of spectroscopic analysis and comparison with literature data. Activity was assessed against Candida albicans, C. parapsilosis and C. krusei using the microdilution method, and against four enzymes of metabolic significance: glucose-6-phosphate dehydrogenase, human erythrocyte carbonic anhydrase I and II, and glutathione S-transferase. Results: Seven compounds, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside; 3-O-methylellagic acid; arjungenin or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid; arjunglucoside or 2,3,19,23-tetrahydroxyolean-12-en-28-oïc acid glucopyranoside; 2α,3α,24-trihydroxyolean-11,13(18-dien-28-oïc acid; stigmasterol; and stigmasterol 3-O-β-d-glucopyranoside were isolated from the extract. Among those, 3,3′-di-O-methylellagic acid 4′-O-α-rhamnopyranoside, 3-O-methylellagic acid, and arjunglucoside showed anti-yeast activity comparable to that of reference fluconazole with minimal inhibitory concentrations (MIC below 32 µg/mL. Besides, Arjunglucoside potently inhibited the tested enzymes with 50% inhibitory concentrations (IC50 below 4 µM and inhibitory constant (Ki <3 µM. Conclusions: The results achieved indicate that further SAR studies will likely identify potent hit derivatives that should subsequently enter the drug development pipeline.

  1. Effects of lemongrass oil and citral on hepatic drug-metabolizing enzymes, oxidative stress, and acetaminophen toxicity in rats

    Directory of Open Access Journals (Sweden)

    Chien-Chun Li

    2018-01-01

    Full Text Available The essential oil from a lemongrass variety of Cymbopogon flexuosus [lemongrass oil (LO] is used in various food and aroma industry products and exhibits biological activities, such as anticancer and antimicrobial activities. To investigate the effects of 200 LO (200 mg/kg and 400 LO (400 mg/kg and its major component, citral (240 mg/kg, on drug-metabolizing enzymes, oxidative stress, and acetaminophen toxicity in the liver, male Sprague-Dawley rats were fed a pelleted diet and administered LO or citral by gavage for 2 weeks. After 2 weeks of feeding, the effects of LO and citral on the metabolism and toxicity of acetaminophen were determined. The results showed that rats treated with 400 LO or citral had significantly reduced hepatic testosterone 6β-hydroxylation and ethoxyresorufin O-deethylation activities. In addition, NAD(PH:quinone oxidoreductase 1 activity was significantly increased by citral, and Uridine 5′-diphospho (UDP glucurosyltransferase activity was significantly increased by 400 LO in the rat liver. Treatment with 400 LO or citral reduced lipid peroxidation and reactive oxygen species levels in the liver. After acetaminophen treatment, however, LO and citral treatment resulted in little or no change in plasma alanine aminotransferase activity and acetaminophen-protein adducts content in the liver. Our results indicate that LO and citral may change the activities of drug-metabolizing enzymes and reduce oxidative stress in the liver. However, LO and citral may not affect the detoxification of acetaminophen.

  2. Effects of lemongrass oil and citral on hepatic drug-metabolizing enzymes, oxidative stress, and acetaminophen toxicity in rats.

    Science.gov (United States)

    Li, Chien-Chun; Yu, Hsiang-Fu; Chang, Chun-Hua; Liu, Yun-Ta; Yao, Hsien-Tsung

    2018-01-01

    The essential oil from a lemongrass variety of Cymbopogon flexuosus [lemongrass oil (LO)] is used in various food and aroma industry products and exhibits biological activities, such as anticancer and antimicrobial activities. To investigate the effects of 200 LO (200 mg/kg) and 400 LO (400 mg/kg) and its major component, citral (240 mg/kg), on drug-metabolizing enzymes, oxidative stress, and acetaminophen toxicity in the liver, male Sprague-Dawley rats were fed a pelleted diet and administered LO or citral by gavage for 2 weeks. After 2 weeks of feeding, the effects of LO and citral on the metabolism and toxicity of acetaminophen were determined. The results showed that rats treated with 400 LO or citral had significantly reduced hepatic testosterone 6β-hydroxylation and ethoxyresorufin O-deethylation activities. In addition, NAD(P)H:quinone oxidoreductase 1 activity was significantly increased by citral, and Uridine 5'-diphospho (UDP) glucurosyltransferase activity was significantly increased by 400 LO in the rat liver. Treatment with 400 LO or citral reduced lipid peroxidation and reactive oxygen species levels in the liver. After acetaminophen treatment, however, LO and citral treatment resulted in little or no change in plasma alanine aminotransferase activity and acetaminophen-protein adducts content in the liver. Our results indicate that LO and citral may change the activities of drug-metabolizing enzymes and reduce oxidative stress in the liver. However, LO and citral may not affect the detoxification of acetaminophen. Copyright © 2017. Published by Elsevier B.V.

  3. Crystallographic study of FABP5 as an intracellular endocannabinoid transporter

    International Nuclear Information System (INIS)

    Sanson, Benoît; Wang, Tao; Sun, Jing; Wang, Liqun; Kaczocha, Martin; Ojima, Iwao; Deutsch, Dale; Li, Huilin

    2014-01-01

    FABP5 was recently found to intracellularly transport endocannabinoid signaling lipids. The structures of FABP5 complexed with two endocannabinoids and an inhibitor were solved. Human FABP5 was found to dimerize via a domain-swapping mechanism. This work will help in the development of inhibitors to raise endocannabinoid levels. In addition to binding intracellular fatty acids, fatty-acid-binding proteins (FABPs) have recently been reported to also transport the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG), arachidonic acid derivatives that function as neurotransmitters and mediate a diverse set of physiological and psychological processes. To understand how the endocannabinoids bind to FABPs, the crystal structures of FABP5 in complex with AEA, 2-AG and the inhibitor BMS-309403 were determined. These ligands are shown to interact primarily with the substrate-binding pocket via hydrophobic interactions as well as a common hydrogen bond to the Tyr131 residue. This work advances our understanding of FABP5–endocannabinoid interactions and may be useful for future efforts in the development of small-molecule inhibitors to raise endocannabinoid levels

  4. Crystallographic study of FABP5 as an intracellular endocannabinoid transporter

    Energy Technology Data Exchange (ETDEWEB)

    Sanson, Benoît; Wang, Tao [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Sun, Jing; Wang, Liqun; Kaczocha, Martin [Stony Brook University, Stony Brook, NY 11794-5213 (United States); Ojima, Iwao [Stony Brook University, Stony Brook, NY 1794-3400 (United States); Stony Brook University, Stony Brook, NY 11794-3400 (United States); Deutsch, Dale, E-mail: dale.deutsch@stonybrook.edu [Stony Brook University, Stony Brook, NY 11794-5213 (United States); Stony Brook University, Stony Brook, NY 11794-3400 (United States); Li, Huilin, E-mail: dale.deutsch@stonybrook.edu [Brookhaven National Laboratory, Upton, NY 11973-5000 (United States); Stony Brook University, Stony Brook, NY 11794-5213 (United States); Stony Brook University, Stony Brook, NY 11794-3400 (United States)

    2014-02-01

    FABP5 was recently found to intracellularly transport endocannabinoid signaling lipids. The structures of FABP5 complexed with two endocannabinoids and an inhibitor were solved. Human FABP5 was found to dimerize via a domain-swapping mechanism. This work will help in the development of inhibitors to raise endocannabinoid levels. In addition to binding intracellular fatty acids, fatty-acid-binding proteins (FABPs) have recently been reported to also transport the endocannabinoids anandamide (AEA) and 2-arachidonoylglycerol (2-AG), arachidonic acid derivatives that function as neurotransmitters and mediate a diverse set of physiological and psychological processes. To understand how the endocannabinoids bind to FABPs, the crystal structures of FABP5 in complex with AEA, 2-AG and the inhibitor BMS-309403 were determined. These ligands are shown to interact primarily with the substrate-binding pocket via hydrophobic interactions as well as a common hydrogen bond to the Tyr131 residue. This work advances our understanding of FABP5–endocannabinoid interactions and may be useful for future efforts in the development of small-molecule inhibitors to raise endocannabinoid levels.

  5. Genetic variation in alcohol metabolizing enzymes among Inuit and its relation to drinking patterns

    DEFF Research Database (Denmark)

    Bjerregaard, Peter; Mikkelsen, Stine Schou; Becker, Ulrik

    2014-01-01

    BACKGROUND: Variation in genes involved in alcohol metabolism is associated with drinking patterns worldwide. We compared variation in these genes among the Inuit with published results from the general population of Denmark and, due to the Asian ancestry of the Inuit, with Han Chinese. We analyzed...

  6. Genetic Variants of Homocysteine Metabolizing Enzymes and the Risk of Coronary Artery Disease

    Czech Academy of Sciences Publication Activity Database

    Janošíková, B.; Pavlíková, Markéta; Kocmanová, Dora; Vítová, D.; Veselá, K.; Krupková, L.; Kahleová, R.; Krijt, J.; Kraml, P.; Hyánek, J.; Zvárová, Jana; Anděl, M.; Kožich, V.

    2003-01-01

    Roč. 79, - (2003), s. 167-175 ISSN 1096-7192 R&D Projects: GA MZd NM26; GA MZd NM6548 Keywords : coronary disease * risk factors * genes * homocysteine * metabolism Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 2.038, year: 2003

  7. Thermophilic and thermoacidophilic metabolism genes and enzymes from Alicyclobacillus acidocaldarius and related organisms, methods

    Energy Technology Data Exchange (ETDEWEB)

    Thompson, Vicki S.; Apel, William A.; Lacey, Jeffrey A.; Lee, Brady D.; Reed, David William; Roberto, Francisco F.; Thompson, David N.

    2018-01-30

    Isolated and/or purified polypeptides and nucleic acid sequences encoding polypeptides from Alicyclobacillus acidocaldarius are provided. Further provided are methods for modulating or altering metabolism in a cell using isolated and/or purified polypeptides and nucleic acid sequences from Alicyclobacillus acidocaldarius.

  8. Thermophilic and thermoacidophilic metabolism genes and enzymes from Alicyclobacillus acidocaldarius and related organisms, methods

    Science.gov (United States)

    Thompson, Vicki S; Apel, William A; Reed, David W; Lee, Brady D; Thompson, David N; Roberto, Francisco F; Lacey, Jeffrey A

    2014-05-20

    Isolated and/or purified polypeptides and nucleic acid sequences encoding polypeptides from Alicyclobacillus acidocaldarius are provided. Further provided are methods for modulating or altering metabolism in a cell using isolated and/or purified polypeptides and nucleic acid sequences from Alicyclobacillus acidocaldarius.

  9. Chemical Screening for Bioactivated Electrophilic Metabolites Using Alginate Immobilization of Metabolic Enzymes (AIME) (SOT)

    Science.gov (United States)

    The US EPA's ToxCast program is designed to assess chemical perturbations of molecular and cellular endpoints using a variety of high-throughput screening (HTS) assays. However, existing HTS assays have limited or no xenobiotic metabolism which could lead to a mischaracterization...

  10. Gene expression of transporters and phase I/II metabolic enzymes in murine small intestine during fasting

    Directory of Open Access Journals (Sweden)

    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

  11. Endocannabinoid modulation of homeostatic and non-homeostatic feeding circuits.

    Science.gov (United States)

    Lau, Benjamin K; Cota, Daniela; Cristino, Luigia; Borgland, Stephanie L

    2017-09-15

    The endocannabinoid system has emerged as a key player in the control of eating. Endocannabinoids, including 2-arachidonoylglycerol (2-AG) and anandamide (AEA), modulate neuronal activity via cannabinoid 1 receptors (CB1Rs) in multiple nuclei of the hypothalamus to induce or inhibit food intake depending on nutritional and hormonal status, suggesting that endocannabinoids may act in the hypothalamus to integrate different types of signals informing about the animal's energy needs. In the mesocorticolimbic system, (endo)cannabinoids modulate synaptic transmission to promote dopamine release in response to palatable food. In addition, (endo)cannabinoids act within the nucleus accumbens to increase food's hedonic impact; although this effect depends on activation of CB1Rs at excitatory, but not inhibitory inputs in the nucleus accumbens. While hyperactivation of the endocannabinoid system is typically associated with overeating and obesity, much evidence has emerged in recent years suggesting a more complicated system than first thought - endocannabinoids promote or suppress feeding depending on cell and input type, or modulation by various neuronal or hormonal signals. This review presents our latest knowledge of the endocannabinoid system in non-homeostatic and homeostatic feeding circuits. In particular, we discuss the functional role and cellular mechanism of action by endocannabinoids within the hypothalamus and mesocorticolimbic system, and how these are modulated by neuropeptide signals related to feeding. In light of recent advances and complexity in the field, we review cannabinoid-based therapeutic strategies for the treatment of obesity and how peripheral restriction of CB1R antagonists may provide a different mechanism of weight loss without the central adverse effects. This article is part of the Special Issue entitled "A New Dawn in Cannabinoid Neurobiology". Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Regulation of drug-metabolizing enzymes in infectious and inflammatory disease: implications for biologics-small molecule drug interactions.

    Science.gov (United States)

    Mallick, Pankajini; Taneja, Guncha; Moorthy, Bhagavatula; Ghose, Romi

    2017-06-01

    Drug-metabolizing enzymes (DMEs) are primarily down-regulated during infectious and inflammatory diseases, leading to disruption in the metabolism of small molecule drugs (smds), which are increasingly being prescribed therapeutically in combination with biologics for a number of chronic diseases. The biologics may exert pro- or anti-inflammatory effect, which may in turn affect the expression/activity of DMEs. Thus, patients with infectious/inflammatory diseases undergoing biologic/smd treatment can have complex changes in DMEs due to combined effects of the disease and treatment. Areas covered: We will discuss clinical biologics-SMD interaction and regulation of DMEs during infection and inflammatory diseases. Mechanistic studies will be discussed and consequences on biologic-small molecule combination therapy on disease outcome due to changes in drug metabolism will be highlighted. Expert opinion: The involvement of immunomodulatory mediators in biologic-SMDs is well known. Regulatory guidelines recommend appropriate in vitro or in vivo assessments for possible interactions. The role of cytokines in biologic-SMDs has been documented. However, the mechanisms of drug-drug interactions is much more complex, and is probably multi-factorial. Studies aimed at understanding the mechanism by which biologics effect the DMEs during inflammation/infection are clinically important.

  13. Novel role of a triglyceride-synthesizing enzyme: DGAT1 at the crossroad between triglyceride and cholesterol metabolism.

    Science.gov (United States)

    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

    2016-09-01

    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 significantly decreased in the small intestine and liver upon DGAT1 deficiency/inhibition. Ablation of DGAT1 in the intestine (I-DGAT1(-/-)) alone is sufficient to cause these effects. Consequences of I-DGAT1 deficiency phenocopy findings in whole-body DGAT1(-/-) and DGAT1 inhibitor-treated mice. We show that deficiency/inhibition of DGAT1 affects cholesterol metabolism via reduced chylomicron size and increased trans-intestinal cholesterol excretion. These effects are independent of cholesterol uptake at the apical surface of enterocytes but mediated through altered dietary fatty acid metabolism. Our findings provide insight into a novel role of DGAT1 and identify a pathway by which intestinal DGAT1 deficiency affects whole-body cholesterol homeostasis in mice. Targeting intestinal DGAT1 may represent a novel approach for treating hypercholesterolemia. Copyright © 2016 The Authors. Published by Elsevier B.V. All rights reserved.

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

    Directory of Open Access Journals (Sweden)

    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

  15. In vivo examination of the effects of hydroxycinnamic acid on xenobiotic metabolizing and antioxidant enzymes

    Directory of Open Access Journals (Sweden)

    Semiz Asli

    2017-01-01

    Full Text Available In the last decade, hydroxycinnamic acids (HCA have gained increasing attention from researchers due to their antioxidant potential. The aim of this study was to examine in detail the impact of dietary HCA on particular types of P450 and also selected phase II and antioxidant enzymes in Wistar rat. HCA (10 mM/kg/day, i.p. was administered for ten continuous days. Examination of the activities and mRNA and protein levels revealed that CYP2B, 2C6 and 3A enzyme activities were not altered significantly, with Western blot and qRT-PCR results corroborating this result. While treatment with HCA led to a significant reduction in CYP1A1/CYP1A2-associated enzyme activities, CYP1A1 protein, and mRNA levels were found to be unchanged. Aromatase (CYP19 activity, as well as protein and mRNA levels, were significantly reduced with HCA treatment. On the other hand, the NAD(PH:quinone oxidoreductase 1 (NQO1, catalase (CAT, glutathione peroxidase (GPx and glutathione S-transferases (GSTs activities were increased significantly. Also, HCA treatment significantly increased the GST-mu and GST-theta mRNA levels. These observations may be of importance given the potential use of HCA as a chemopreventive and as an anticancer agent.

  16. Polymorphisms in the endocannabinoid receptor 1 in relation to fat mass distribution

    DEFF Research Database (Denmark)

    Frost, M; Nielsen, T L; Wraae, K

    2010-01-01

    Both animal and human studies have associated the endocannabinoid system with obesity and markers of metabolic dysfunction. Blockade of the cannabinoid receptor 1 (CB1) caused weight loss and reduction in waist size in both obese and type II diabetics. Recent studies on common variants of the CB1...... receptor gene (CNR1) and the link to obesity have been conflicting. The aim of the present study was to evaluate whether selected common variants of the CNR1 are associated with measures of obesity and fat distribution....

  17. Neural expression and post-transcriptional dosage compensation of the steroid metabolic enzyme 17β-HSD type 4

    Directory of Open Access Journals (Sweden)

    Wise Petra M

    2010-04-01

    Full Text Available Abstract Background Steroids affect many tissues, including the brain. In the zebra finch, the estrogenic steroid estradiol (E2 is especially effective at promoting growth of the neural circuit specialized for song. In this species, only the males sing and they have a much larger and more interconnected song circuit than females. Thus, it was surprising that the gene for 17β-hydroxysteroid dehydrogenase type 4 (HSD17B4, an enzyme that converts E2 to a less potent estrogen, had been mapped to the Z sex chromosome. As a consequence, it was likely that HSD17B4 was differentially expressed in males (ZZ and females (ZW because dosage compensation of Z chromosome genes is incomplete in birds. If a higher abundance of HSD17B4 mRNA in males than females was translated into functional enzyme in the brain, then contrary to expectation, males could produce less E2 in their brains than females. Results Here, we used molecular and biochemical techniques to confirm the HSD17B4 Z chromosome location in the zebra finch and to determine that HSD17B4 mRNA and activity were detectable in the early developing and adult brain. As expected, HSD17B4 mRNA expression levels were higher in males compared to females. This provides further evidence of the incomplete Z chromosome inactivation mechanisms in birds. We detected HSD17B4 mRNA in regions that suggested a role for this enzyme in the early organization and adult function of song nuclei. We did not, however, detect significant sex differences in HSD17B4 activity levels in the adult brain. Conclusions Our results demonstrate that the HSD17B4 gene is expressed and active in the zebra finch brain as an E2 metabolizing enzyme, but that dosage compensation of this Z-linked gene may occur via post-transcriptional mechanisms.

  18. Polyphenols as enzyme inhibitors in different degraded peat soils: Implication for microbial metabolism in rewetted peatlands

    Science.gov (United States)

    Zak, Dominik; Roth, Cyril; Gelbrecht, Jörg; Fenner, Nathalie; Reuter, Hendrik

    2015-04-01

    Recently, more than 30,000 ha of drained minerotrophic peatlands (= fens) in NE Germany were rewetted to restore their ecological functions. Due to an extended drainage history, a re-establishment of their original state is not expected in the short-term. Elevated concentrations of dissolved organic carbon, ammonium and phosphate have been measured in the soil porewater of the upper degraded peat layers of rewetted fens at levels of one to three orders higher than the values in pristine systems; an indicator of increased microbial activity in the upper degraded soil layers. On the other hand there is evidence that the substrate availability within the degraded peat layer is lowered since the organic matter has formerly been subject to intense decomposition over the decades of drainage and intense agricultural use of the areas. Previously however, it was suggested that inhibition of hydrolytic enzymes by polyphenolic substances is suspended during aeration of peat soils mainly due to the decomposition of the inhibiting polyphenols by oxidising enzymes such as phenol oxidase. Accordingly we hypothesised a lack of enzyme inhibiting polyphenols in degraded peat soils of rewetted fens compared to less decomposed peat of more natural fens. We collected both peat samples at the soil surface (0-20 cm) and fresh roots of dominating vascular plants and mosses (as peat parent material) from five formerly drained rewetted sites and five more natural sites of NE Germany and NW Poland. Less decomposed peat and living roots were used to obtain an internal standard for polyphenol analysis and to run enzyme inhibition tests. For all samples we determined the total phenolic contents and in addition we distinguished between the contents of hydrolysable and condensed tannic substances. From a methodical perspective the advantage of internal standards compared to the commercially available standards cyanidin chloride and tannic acid became apparent. Quantification with cyanidin or

  19. Dynamic regulation of the endocannabinoid system: implications for analgesia

    Directory of Open Access Journals (Sweden)

    Wong Amy

    2009-10-01

    Full Text Available Abstract The analgesic effects of cannabinoids are well documented, but these are often limited by psychoactive side-effects. Recent studies indicate that the endocannabinoid system is dynamic and altered under different pathological conditions, including pain states. Changes in this receptor system include altered expression of receptors, differential synthetic pathways for endocannabinoids are expressed by various cell types, multiple pathways of catabolism and the generation of biologically active metabolites, which may be engaged under different conditions. This review discusses the evidence that pain states alter the endocannabinoid receptor system at key sites involved in pain processing and how these changes may inform the development of cannabinoid-based analgesics.

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

    Science.gov (United States)

    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

  1. Clinical Endocannabinoid Deficiency Reconsidered: Current Research Supports the Theory in Migraine, Fibromyalgia, Irritable Bowel, and Other Treatment-Resistant Syndromes.

    Science.gov (United States)

    Russo, Ethan B

    2016-01-01

    Medicine continues to struggle in its approaches to numerous common subjective pain syndromes that lack objective signs and remain treatment resistant. Foremost among these are migraine, fibromyalgia, and irritable bowel syndrome, disorders that may overlap in their affected populations and whose sufferers have all endured the stigma of a psychosomatic label, as well as the failure of endless pharmacotherapeutic interventions with substandard benefit. The commonality in symptomatology in these conditions displaying hyperalgesia and central sensitization with possible common underlying pathophysiology suggests that a clinical endocannabinoid deficiency might characterize their origin. Its base hypothesis is that all humans have an underlying endocannabinoid tone that is a reflection of levels of the endocannabinoids, anandamide (arachidonylethanolamide), and 2-arachidonoylglycerol, their production, metabolism, and the relative abundance and state of cannabinoid receptors. Its theory is that in certain conditions, whether congenital or acquired, endocannabinoid tone becomes deficient and productive of pathophysiological syndromes. When first proposed in 2001 and subsequently, this theory was based on genetic overlap and comorbidity, patterns of symptomatology that could be mediated by the endocannabinoid system (ECS), and the fact that exogenous cannabinoid treatment frequently provided symptomatic benefit. However, objective proof and formal clinical trial data were lacking. Currently, however, statistically significant differences in cerebrospinal fluid anandamide levels have been documented in migraineurs, and advanced imaging studies have demonstrated ECS hypofunction in post-traumatic stress disorder. Additional studies have provided a firmer foundation for the theory, while clinical data have also produced evidence for decreased pain, improved sleep, and other benefits to cannabinoid treatment and adjunctive lifestyle approaches affecting the ECS.

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

    OpenAIRE

    Przemysław eKaczor; Dariusz eRakus; Jerzy Władysław Mozrzymas; Jerzy Władysław Mozrzymas

    2015-01-01

    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 astrocy...

  3. Antisense Suppression of 2-Cysteine Peroxiredoxin in Arabidopsis Specifically Enhances the Activities and Expression of Enzymes Associated with Ascorbate Metabolism But Not Glutathione Metabolism1

    Science.gov (United States)

    Baier, Margarete; Noctor, Graham; Foyer, Christine H.; Dietz, Karl-Josef

    2000-01-01

    The aim of this study was to characterize the effect of decreased 2-cysteine peroxiredoxin (2-CP) on the leaf anti-oxidative system in Arabidopsis. At three stages of leaf development, two lines of transgenic Arabidopsis mutants with decreased contents of chloroplast 2-CP were compared with wild type and a control line transformed with an empty vector. Glutathione contents and redox state were similar in all plants, and no changes in transcript levels for enzymes involved in glutathione metabolism were observed. Transcript levels for chloroplastic glutathione peroxidase were much lower than those for 2-CP, and both cytosolic and chloroplastic glutathione peroxidase were not increased in the mutants. In contrast, the foliar ascorbate pool was more oxidized in the mutants, although the difference decreased with plant age. The activities of thylakoid and stromal ascorbate peroxidase and particularly monodehydroascorbate reductase were increased as were transcripts for these enzymes. No change in dehydroascorbate reductase activity was observed, and effects on transcript abundance for glutathione reductase, catalase, and superoxide dismutase were slight or absent. The results demonstrate that 2-CP forms an integral part of the anti-oxidant network of chloroplasts and is functionally interconnected with other defense systems. Suppression of 2-CP leads to increased expression of other anti-oxidative genes possibly mediated by increased oxidation state of the leaf ascorbate pool. PMID:11027730

  4. Functional characterization of proanthocyanidin pathway enzymes from tea and their application for metabolic engineering.

    Science.gov (United States)

    Pang, Yongzhen; Abeysinghe, I Sarath B; He, Ji; He, Xianzhi; Huhman, David; Mewan, K Mudith; Sumner, Lloyd W; Yun, Jianfei; Dixon, Richard A

    2013-03-01

    Tea (Camellia sinensis) is rich in specialized metabolites, especially polyphenolic proanthocyanidins (PAs) and their precursors. To better understand the PA pathway in tea, we generated a complementary DNA library from leaf tissue of the blister blight-resistant tea cultivar TRI2043 and functionally characterized key enzymes responsible for the biosynthesis of PA precursors. Structural genes encoding enzymes involved in the general phenylpropanoid/flavonoid pathway and the PA-specific branch pathway were well represented in the library. Recombinant tea leucoanthocyanidin reductase (CsLAR) expressed in Escherichia coli was active with leucocyanidin as substrate to produce the 2R,3S-trans-flavan-ol (+)-catechin in vitro. Two genes encoding anthocyanidin reductase, CsANR1 and CsANR2, were also expressed in E. coli, and the recombinant proteins exhibited similar kinetic properties. Both converted cyanidin to a mixture of (+)-epicatechin and (-)-catechin, although in different proportions, indicating that both enzymes possess epimerase activity. These epimers were unexpected based on the belief that tea PAs are made from (-)-epicatechin and (+)-catechin. Ectopic expression of CsANR2 or CsLAR led to the accumulation of low levels of PA precursors and their conjugates in Medicago truncatula hairy roots and anthocyanin-overproducing tobacco (Nicotiana tabacum), but levels of oligomeric PAs were very low. Surprisingly, the expression of CsLAR in tobacco overproducing anthocyanin led to the accumulation of higher levels of epicatechin and its glucoside than of catechin, again highlighting the potential importance of epimerization in flavan-3-ol biosynthesis. These data provide a resource for understanding tea PA biosynthesis and tools for the bioengineering of flavanols.

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

    Science.gov (United States)

    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.

  6. Chlorophyll-derived fatty acids regulate expression of lipid metabolizing enzymes in liver - a nutritional opportunity

    Directory of Open Access Journals (Sweden)

    Wolfrum Christian

    2001-01-01

    Full Text Available Nutritional values of fatty acid classes are normally discussed on the basis of their saturated, monounsaturated and polyunsaturated structures with implicit understanding that they are straight-chain. Here we focus on chlorophyll-derived phytanic and pristanic acids that are minor isoprenoid branched-chain lipid constituents in food, but of unknown nutritional value. After describing the enzyme machinery that degrades these nutrient fatty acids in the peroxisome, we show by the criteria of a mouse model and of a human cell culture model that they induce with high potency expression of enzymes responsible for beta-oxidation of straight-chain fatty acids in the peroxisome. We summarize present mechanistic knowledge on fatty acid signaling to the nucleus, which involves protein/protein contacts between peroxisome proliferator activated receptor (PPAR and fatty acid binding protein (FABP. In this signaling event the branched-chain fatty acids are the most effective ones. Finally, on the basis of this nutrient-gene interaction we discuss nutritional opportunities and therapeutic aspects of the chlorophyll-derived fatty acids.

  7. Impaired endocannabinoid signalling in the rostral ventromedial medulla underpins genotype-dependent hyper-responsivity to noxious stimuli.

    Science.gov (United States)

    Rea, Kieran; Olango, Weredeselam M; Okine, Bright N; Madasu, Manish K; McGuire, Iseult C; Coyle, Kathleen; Harhen, Brendan; Roche, Michelle; Finn, David P

    2014-01-01

    Pain is both a sensory and an emotional experience, and is subject to modulation by a number of factors including genetic background modulating stress/affect. The Wistar-Kyoto (WKY) rat exhibits a stress-hyper-responsive and depressive-like phenotype and increased sensitivity to noxious stimuli, compared with other rat strains. Here, we show that this genotype-dependent hyperalgesia is associated with impaired pain-related mobilisation of endocannabinoids and transcription of their synthesising enzymes in the rostral ventromedial medulla (RVM). Pharmacological blockade of the Cannabinoid1 (CB1) receptor potentiates the hyperalgesia in WKY rats, whereas inhibition of the endocannabinoid catabolising enzyme, fatty acid amide hydrolase, attenuates the hyperalgesia. The latter effect is mediated by CB1 receptors in the RVM. Together, these behavioural, neurochemical, and molecular data indicate that impaired endocannabinoid signalling in the RVM underpins hyper-responsivity to noxious stimuli in a genetic background prone to heightened stress/affect. Copyright © 2013 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  8. Radiation effects on testes. XI. Studies on glycogen and its metabolizing enzymes following radiation-induced atrophy

    International Nuclear Information System (INIS)

    Gupta, G.S.; Bawa, S.R.

    1977-01-01

    Effect of radiation on enzymes of carbohydrate metabolism has been studied. It is observed that hexokinase of testis is highly sensitive to radiation damage. Reduced hexokinase activity seems to be related to those parts of the testis (spermatocytes and spermatids) which depend upon glucose for their functioning. Radiation-induced atrophic testis is rich in glycogen content. The observations on the inhibition of gluocose-6-phosphatase and phosphorylase may explain the higher levels of the polysaccharide although a possibility of enhanced glycogenesis due to the activation of glycogen synthetase has also been suggested. The presence of glucose-6-phosphate isomerase and glycogen in atrophied testis in 11-month-treated rats indicate the higher glycolytic activity with hyperplastic testicular interstitium. The results suggest that the accumulated glycogen is acting as a reserve substrate in nongerminal cells

  9. Methods for the Isolation of Genes Encoding Novel PHA Metabolism Enzymes from Complex Microbial Communities.

    Science.gov (United States)

    Cheng, Jiujun; Nordeste, Ricardo; Trainer, Maria A; Charles, Trevor C

    2017-01-01

    Development of different PHAs as alternatives to petrochemically derived plastics can be facilitated by mining metagenomic libraries for diverse PHA cycle genes that might be useful for synthesis of bio-plastics. The specific phenotypes associated with mutations of the PHA synthesis pathway genes in Sinorhizobium meliloti and Pseudomonas putida, allows the use of powerful selection and screening tools to identify complementing novel PHA synthesis genes. Identification of novel genes through their function rather than sequence facilitates the functional proteins that may otherwise have been excluded through sequence-only screening methodology. We present here methods that we have developed for the isolation of clones expressing novel PHA metabolism genes from metagenomic libraries.

  10. Protective Effect of Free and Bound Polyphenol Extracts from Ginger (Zingiber officinale Roscoe) on the Hepatic Antioxidant and Some Carbohydrate Metabolizing Enzymes of Streptozotocin-Induced Diabetic Rats

    OpenAIRE

    Kazeem, Mutiu Idowu; Akanji, Musbau Adewunmi; Yakubu, Musa Toyin; Ashafa, Anofi Omotayo Tom

    2013-01-01

    This study investigated the hepatoprotective effects of polyphenols from Zingiber officinale on streptozotocin-induced diabetic rats by assessing liver antioxidant enzymes, carbohydrate-metabolizing enzymes and liver function indices. Initial oral glucose tolerance test was conducted using 125?mg/kg, 250?mg/kg, and 500?mg/kg body weight of both free and bound polyphenols from Z. officinale. 28 day daily oral administration of 500?mg/kg body weight of free and bound polyphenols from Z. officin...

  11. Endocannabinoids and the processing of value-related signals

    Directory of Open Access Journals (Sweden)

    Miriam eMelis

    2012-02-01

    Full Text Available Endocannabinoids serve as retrograde signaling molecules at many synapses within the CNS, particularly GABAergic and glutamatergic synapses. Synapses onto midbrain dopamine (DA neurons in the ventral tegmental area (VTA make no exception to this rule. In fact, the effects of cannabinoids on dopamine transmission as well as DA-related behaviors are generally exerted through the modulation of inhibitory and excitatory afferents impinging onto DA neurons. Endocannabinoids, by regulating different forms of synaptic plasticity in the VTA, provide a critical modulation of the DA neuron output and, ultimately, of the systems driving and regulating motivated behaviors. Because DA cells exhibit diverse states of activity, which crucially depend on their intrinsic properties and afferent drive, the understanding of the role played by endocannabinoids in synaptic modulations is critical for their overall functions. Particularly, endocannabinoids by selectively inhibiting afferent activity may alter the functional states of DA neurons and potentiate the responsiveness of the reward system to phasic DA.

  12. Metabolism of inositol(1,4,5)trisphosphate by a soluble enzyme fraction from pea (Pisum sativum) roots

    International Nuclear Information System (INIS)

    Drobak, B.K.; Watkins, P.A.C.; Roberts, K.; Chattaway, J.A.; Dawson, A.P.

    1991-01-01

    Metabolism of the putative messenger molecule D-myo-inositol(1,4,5)trisphosphate [Ins(1,4,5)P 3 ] in plant cells has been studied using a soluble fraction from pea (pisum sativum) roots as enzyme source and [5- 32 P]Ins(1,4,5)P 3 and [2- 3 H]Ins(1,4,5)P 3 as tracers. Ins(1,4,5)P 3 was rapidly converted into both lower and higher inositol phosphates. The major dephosphorylation product was inositol (4,5) bisphosphate [Ins(4,5)P 2 ] whereas inositol(1,4)bisphosphate [Ins(1,4)P 2 ] was only present in very small quantities throughout a 15 minute incubation period. In addition to these compounds, small amounts of nine other metabolites were produced including inositol and inositol(1,4,5,X)P 4 . Dephosphorylation of Ins(1,4,5)P 3 to Ins(4,5)P 2 was dependent on Ins(1,4,5)P 3 concentration and was partially inhibited by the phosphohydrolase inhibitors 2,3-diphosphoglycerate, glucose 6-phosphate, and p-nitrophenylphosphate. Conversion of Ins(1,4,5)P 3 to Ins(4,5)P 2 and Ins(1,4,5,X)P 4 was inhibited by 55 micromolar Ca 2+ . This study demonstrates that enzymes are present in plant tissues which are capable of rapidly converting Ins(1,4,5)P 3 and that pathways of inositol phosphate metabolism exist which may prove to be unique to the plant kingdom

  13. Protein profiling of plastoglobules in chloroplasts and chromoplasts. A surprising site for differential accumulation of metabolic enzymes.

    Science.gov (United States)

    Ytterberg, A Jimmy; Peltier, Jean-Benoit; van Wijk, Klaas J

    2006-03-01

    Plastoglobules (PGs) are oval or tubular lipid-rich structures present in all plastid types, but their specific functions are unclear. PGs contain quinones, alpha-tocopherol, and lipids and, in chromoplasts, carotenoids as well. It is not known whether PGs contain any enzymes or regulatory proteins. Here, we determined the proteome of PGs from chloroplasts of stressed and unstressed leaves of Arabidopsis (Arabidopsis thaliana) as well as from pepper (Capsicum annuum) fruit chromoplasts using mass spectrometry. Together, this showed that the proteome of chloroplast PGs consists of seven fibrillins, providing a protein coat and preventing coalescence of the PGs, and an additional 25 proteins likely involved in metabolism of isoprenoid-derived molecules (quinines and tocochromanols), lipids, and carotenoid cleavage. Four unknown ABC1 kinases were identified, possibly involved in regulation of quinone monooxygenases. Most proteins have not been observed earlier but have predicted N-terminal chloroplast transit peptides and lack transmembrane domains, consistent with localization in the PG lipid monolayer particles. Quantitative differences in PG composition in response to high light stress and degreening were determined by differential stable-isotope labeling using formaldehyde. More than 20 proteins were identified in the PG proteome of pepper chromoplasts, including four enzymes of carotenoid biosynthesis and several homologs of proteins observed in the chloroplast PGs. Our data strongly suggest that PGs in chloroplasts form a functional metabolic link between the inner envelope and thylakoid membranes and play a role in breakdown of carotenoids and oxidative stress defense, whereas PGs in chromoplasts are also an active site for carotenoid conversions.

  14. Protein Profiling of Plastoglobules in Chloroplasts and Chromoplasts. A Surprising Site for Differential Accumulation of Metabolic Enzymes1[W

    Science.gov (United States)

    Ytterberg, A. Jimmy; Peltier, Jean-Benoit; van Wijk, Klaas J.

    2006-01-01

    Plastoglobules (PGs) are oval or tubular lipid-rich structures present in all plastid types, but their specific functions are unclear. PGs contain quinones, α-tocopherol, and lipids and, in chromoplasts, carotenoids as well. It is not known whether PGs contain any enzymes or regulatory proteins. Here, we determined the proteome of PGs from chloroplasts of stressed and unstressed leaves of Arabidopsis (Arabidopsis thaliana) as well as from pepper (Capsicum annuum) fruit chromoplasts using mass spectrometry. Together, this showed that the proteome of chloroplast PGs consists of seven fibrillins, providing a protein coat and preventing coalescence of the PGs, and an additional 25 proteins likely involved in metabolism of isoprenoid-derived molecules (quinines and tocochromanols), lipids, and carotenoid cleavage. Four unknown ABC1 kinases were identified, possibly involved in regulation of quinone monooxygenases. Most proteins have not been observed earlier but have predicted N-terminal chloroplast transit peptides and lack transmembrane domains, consistent with localization in the PG lipid monolayer particles. Quantitative differences in PG composition in response to high light stress and degreening were determined by differential stable-isotope labeling using formaldehyde. More than 20 proteins were identified in the PG proteome of pepper chromoplasts, including four enzymes of carotenoid biosynthesis and several homologs of proteins observed in the chloroplast PGs. Our data strongly suggest that PGs in chloroplasts form a functional metabolic link between the inner envelope and thylakoid membranes and play a role in breakdown of carotenoids and oxidative stress defense, whereas PGs in chromoplasts are also an active site for carotenoid conversions. PMID:16461379

  15. Overexpression of Genes Encoding Glycolytic Enzymes in Corynebacterium glutamicum Enhances Glucose Metabolism and Alanine Production under Oxygen Deprivation Conditions

    Science.gov (United States)

    Yamamoto, Shogo; Gunji, Wataru; Suzuki, Hiroaki; Toda, Hiroshi; Suda, Masako; Jojima, Toru; Inui, Masayuki

    2012-01-01

    We previously reported that Corynebacterium glutamicum strain ΔldhAΔppc+alaD+gapA, overexpressing glyceraldehyde-3-phosphate dehydrogenase-encoding gapA, shows significantly improved glucose consumption and alanine formation under oxygen deprivation conditions (T. Jojima, M. Fujii, E. Mori, M. Inui, and H. Yukawa, Appl. Microbiol. Biotechnol. 87:159–165, 2010). In this study, we employ stepwise overexpression and chromosomal integration of a total of four genes encoding glycolytic enzymes (herein referred to as glycolytic genes) to demonstrate further successive improvements in C. glutamicum glucose metabolism under oxygen deprivation. In addition to gapA, overexpressing pyruvate kinase-encoding pyk and phosphofructokinase-encoding pfk enabled strain GLY2/pCRD500 to realize respective 13% and 20% improved rates of glucose consumption and alanine formation compared to GLY1/pCRD500. Subsequent overexpression of glucose-6-phosphate isomerase-encoding gpi in strain GLY3/pCRD500 further improved its glucose metabolism. Notably, both alanine productivity and yield increased after each overexpression step. After 48 h of incubation, GLY3/pCRD500 produced 2,430 mM alanine at a yield of 91.8%. This was 6.4-fold higher productivity than that of the wild-type strain. Intracellular metabolite analysis showed that gapA overexpression led to a decreased concentration of metabolites upstream of glyceraldehyde-3-phosphate dehydrogenase, suggesting that the overexpression resolved a bottleneck in glycolysis. Changing ratios of the extracellular metabolites by overexpression of glycolytic genes resulted in reduction of the intracellular NADH/NAD+ ratio, which also plays an important role on the improvement of glucose consumption. Enhanced alanine dehydrogenase activity using a high-copy-number plasmid further accelerated the overall alanine productivity. Increase in glycolytic enzyme activities is a promising approach to make drastic progress in growth-arrested bioprocesses. PMID

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

    Directory of Open Access Journals (Sweden)

    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.

  17. 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...

  18. Regulation of phase I and phase II steroid metabolism enzymes by PPARα activators

    International Nuclear Information System (INIS)

    Fan Liqun; You Li; Brown-Borg, Holly; Brown, Sherri; Edwards, Robert J.; Corton, J. Christopher

    2004-01-01

    Peroxisome proliferators (PP) are a large class of structurally diverse chemicals that mediate their effects in the liver mainly through the peroxisome proliferator-activated receptor α (PPARα). Exposure to some PP results in alterations of steroid levels that may be mechanistically linked to adverse effects in reproductive organs. We hypothesized that changes in steroid levels after PP exposure are due to alterations in the levels of P450 enzymes that hydroxylate testosterone and estrogen. In testosterone hydroxylase assays, exposure to the PP, WY-14,643 (WY), gemfibrozil or di-n-butyl phthalate (DBP) led to compound-specific increases in 6β and 16β-testosterone and androstenedione hydroxylase activities and decreases in 16α, 2α-hydroxylase activities by all three PP. The decreases in 16α and 2α-testosterone hydroxylase activity can be attributed to a 2α and 16α- testosterone hydroxylase, CYP2C11, which we previously showed was dramatically down-regulated in these same tissues (Corton et al., 1998; Mol. Pharmacol. 54, 463-473). To explain the increases in 6β- and 16β-testosterone hydroxylase activities, we examined the expression of P450 family members known to carry out these functions. Alterations in the 6β-testosterone hydroxylases CYP3A1, CYP3A2 and the 16β-testosterone hydroxylase, CYP2B1 were observed after exposure to some PP. The male-specific estrogen sulfotransferase was down-regulated in rat liver after exposure to all PP. The mouse 6β-testosterone hydroxylase, Cyp3a11 was down-regulated by WY in wild-type but not PPARα-null mice. In contrast, DEHP increased Cyp3a11 in both wild-type and PPARα-null mice. These studies demonstrate that PP alter the expression and activity of a number of enzymes which regulate levels of sex steroids. The changes in these enzymes may help explain why exposure to some PP leads to adverse effects in endocrine tissues that produce or are the targets of sex hormones

  19. Rapid selection of a pyrethroid metabolic enzyme CYP9K1 by operational malaria control activities.

    Science.gov (United States)

    Vontas, John; Grigoraki, Linda; Morgan, John; Tsakireli, Dimitra; Fuseini, Godwin; Segura, Luis; Niemczura de Carvalho, Julie; Nguema, Raul; Weetman, David; Slotman, Michel A; Hemingway, Janet

    2018-05-01

    Since 2004, indoor residual spraying (IRS) and long-lasting insecticide-impregnated bednets (LLINs) have reduced the malaria parasite prevalence in children on Bioko Island, Equatorial Guinea, from 45% to 12%. After target site-based (knockdown resistance; kdr ) pyrethroid resistance was detected in 2004 in Anopheles coluzzii (formerly known as the M form of the Anopheles gambiae complex), the carbamate bendiocarb was introduced. Subsequent analysis showed that kdr alone was not operationally significant, so pyrethroid-based IRS was successfully reintroduced in 2012. In 2007 and 2014-2015, mass distribution of new pyrethroid LLINs was undertaken to increase the net coverage levels. The combined selection pressure of IRS and LLINs resulted in an increase in the frequency of pyrethroid resistance in 2015. In addition to a significant increase in kd r frequency, an additional metabolic pyrethroid resistance mechanism had been selected. Increased metabolism of the pyrethroid deltamethrin was linked with up-regulation of the cytochrome P450 CYP9K1. The increase in resistance prompted a reversion to bendiocarb IRS in 2016 to avoid a resurgence of malaria, in line with the national Malaria Control Program plan. Copyright © 2018 the Author(s). Published by PNAS.

  20. ENDOCANNABINOIDS AND EICOSAMOIDS: BIOSYNTHESIS AND INTERACTIONS WITH IMMUNE RESPONSE

    Directory of Open Access Journals (Sweden)

    Yu. K. Karaman

    2013-01-01

    Full Text Available The review is dedicated to modern concepts of arachidonic acid metabolites, i.e., endocannabinoids and eicosanoids, their biosynthetic pathways, cross-talk mechanisms and participation in immune response. New information from literature and own results include data concerning overlapping enzymatic pathways controlling biosynthesis of endocannabinoids and eicosanoids. Impact of synthetic cannabinoid receptor ligands upon production rates of proinflammatory cytokines and eicosanoids is discussed, as like as relationships among immune system reactivity and expression levels of cannabinoid receptors.

  1. Caloric restriction counteracts age-related changes in the activities of sorbitol metabolizing enzymes from mouse liver

    Science.gov (United States)

    Hagopian, Kevork; Ramsey, Jon J.; Weindruch, Richard

    2009-01-01

    The influence of caloric restriction (CR) on hepatic sorbitol-metabolizing enzyme activities was investigated in young and old mice. Aldose reductase and sorbitol dehydrogenase activities were significantly lower in old CR mice than in old controls. Young CR mice showed decreased aldose reductase activity and a trend towards decreased sorbitol dehydrogenase when compared to controls. Metabolites of the pathway, namely sorbitol, glucose and fructose were decreased by CR in young and old mice. Pyruvate levels were decreased by CR in both young and old mice, while lactate decreased only in old CR. Malate levels increased in old CR but remained unchanged in young CR, when compared with controls. Accordingly, the lactae/pyruvate and malate/pyruvate ratios in young and old CR mice were increased, indicating increased NADH/NAD and NADPH/NADP redox couples, respectively. The results indicate that decreased glucose levels under CR conditions lead to decreased sorbitol pathway enzyme activities and metabolite levels, and could contribute to the beneficial effects of long-term CR through decreased sorbitol levels and NADPH sparing. PMID:18953666

  2. KINETICS OF MODULATORY ROLE OF Cyperus esculentus L. ON THE SPECIFIC ACTIVITY OF KEY CARBOHYDRATE METABOLIZING ENZYMES.

    Science.gov (United States)

    Sabiu, Saheed; Ajani, Emmanuel Oladipo; Sunmonu, Taofik Olatunde; Ashafa, Anofi Omotayo Tom

    2017-01-01

    The continuous search for new lead compounds as viable inhibitors of specific enzymes linked to carbohydrate metabolism has intensified. Cyperus esculentus L. is one of the therapeutically implicated botanicals against several degenerative diseases including diabetes mellitus. This study evaluated the antioxidant and mechanism(s) of inhibitory potential of aqueous extract of C. esculentus on α-amylase and α-glucosidase in vitro . The extract was investigated for its radical scavenging and hypoglycaemic potentials using standard experimental procedures. Lineweaver-Burke plot was used to predict the manner in which the enzymes were inhibited. The data obtained revealed that the extract moderately and potently inhibited the specific activities of α -amylase and α -glucosidase, respectively. The inhibition was concentration-related with respective IC 50 values of 5.19 and 0.78 mg/mL relative to that of the control (3.72 and 3.55 mg/mL). The extract also significantly scavenged free radicals and the effects elicited could be ascribed to its phytoconstituents. The respective competitive and non-competitive mode of action of the extract is due to its inhibitory potentials on the activities of α -amylase and α -glucosidase. Going forward, in addition to completely characterize the exact compound(s) responsible for the elicited activity in this study, pertinent attention will be given to the in vivo evaluation of the identified constituents.

  3. Final Project Report - Coupled Biogeochemical Process Evaluation for Conceptualizing Trichloriethylene Co-Metabolism: Co-Metabolic Enzyme Activity Probes and Modeling Co-Metabolism and Attenuation

    Energy Technology Data Exchange (ETDEWEB)

    Starr, Robert C; Orr, Brennon R; Lee, M Hope; Delwiche, Mark

    2010-02-26

    Trichloroethene (TCE) (also known as trichloroethylene) is a common contaminant in groundwater. TCE is regulated in drinking water at a concentration of 5 µg/L, and a small mass of TCE has the potential to contaminant large volumes of water. The physical and chemical characteristics of TCE allow it to migrate quickly in most subsurface environments, and thus large plumes of contaminated groundwater can form from a single release. The migration and persistence of TCE in groundwater can be limited by biodegradation. TCE can be biodegraded via different processes under either anaerobic or aerobic conditions. Anaerobic biodegradation is widely recognized, but aerobic degradation is less well recognized. Under aerobic conditions, TCE can be oxidized to non hazardous conditions via cometabolic pathways. This study applied enzyme activity probes to demonstrate that cometabolic degradation of TCE occurs in aerobic groundwater at several locations, used laboratory microcosm studies to determine aerobic degradation rates, and extrapolated lab-measured rates to in situ rates based on concentrations of microorganisms with active enzymes involved in cometabolic TCE degradation. Microcosms were constructed using basalt chips that were inoculated with microorganisms to groundwater at the Idaho National Laboratory Test Area North TCE plume by filling a set of Flow-Through In Situ Reactors (FTISRs) with chips and placing the FTISRs into the open interval of a well for several months. A parametric study was performed to evaluate predicted degradation rates and concentration trends using a competitive inhibition kinetic model, which accounts for competition for enzyme active sites by both a growth substrate and a cometabolic substrate. The competitive inhibition kinetic expression was programmed for use in the RT3D reactive transport package. Simulations of TCE plume evolution using both competitive inhibition kinetics and first order decay were performed.

  4. Drug metabolism by cytochrome p450 enzymes: what distinguishes the pathways leading to substrate hydroxylation over desaturation?

    Science.gov (United States)

    Ji, Li; Faponle, Abayomi S; Quesne, Matthew G; Sainna, Mala A; Zhang, Jing; Franke, Alicja; Kumar, Devesh; van Eldik, Rudi; Liu, Weiping; de Visser, Sam P

    2015-06-15

    Cytochrome P450 enzymes are highly versatile biological catalysts in our body that react with a broad range of substrates. Key functions in the liver include the metabolism of drugs and xenobiotics. One particular metabolic pathway that is poorly understood relates to the P450 activation of aliphatic groups leading to either hydroxylation or desaturation pathways. A DFT and QM/MM study has been carried out on the factors that determine the regioselectivity of aliphatic hydroxylation over desaturation of compounds by P450 isozymes. The calculations establish multistate reactivity patterns, whereby the product distributions differ on each of the spin-state surfaces; hence spin-selective product formation was found. The electronic and thermochemical factors that determine the bifurcation pathways were analysed and a model that predicts the regioselectivity of aliphatic hydroxylation over desaturation pathways was established from valence bond and molecular orbital theories. Thus, the difference in energy of the OH versus the OC bond formed and the π-conjugation energy determines the degree of desaturation products. In addition, environmental effects of the substrate binding pocket that affect the regioselectivities were identified. These studies imply that bioengineering P450 isozymes for desaturation reactions will have to include modifications in the substrate binding pocket to restrict the hydroxylation rebound reaction. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The Effects of Space Flight on Some Liver Enzymes Concerned with Carbohydrate and Lipid Metabolism in Rats

    Science.gov (United States)

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

    1978-01-01

    The activities of about 30 enzymes concerned with carbohydrate and lipid metabolism and the levels of glycogen and of individual fatty acids were measured in livers of rats ex- posed to prolonged space flight (18.5 days) aboard COSMOS 986 Biosatellite. When flight stationary, (FS) and flight centrifuged (FC) rats were compared at recovery (R(sub 0)), decrceases in the activities of glycogen phosphorylase, alpha glycerphosphate, acyl transferase, diglyceride acyl transferase, acconitase and Epsilon-phosphogluconate dehydrogenase were noted in the weightless group (FS). The significance of these findings was strengthened since all activities, showing alterations at R(sub 0), returned to normal 25 days post-flight. Differences were also seen in levels of two liver constituents. When glycogen and total fatty acids of the two groups of flight animals were determined, differences that could be attributed to reduced gravity were observed, the FS group at R(sub 0) contained, on the average, more than twice the amount of glycogen than did controls ad a remarkable shift in the ratio of palmitate to palmitoleate were noted. These metabolic alterations appear to be unique to the weightless condition. Our data justify the conclusion that centrifugation during space flight is equivalent to terrestrial gravity.

  6. Western Blotting of the Endocannabinoid System.

    Science.gov (United States)

    Wager-Miller, Jim; Mackie, Ken

    2016-01-01

    Measuring expression levels of G protein-coupled receptors (GPCRs) is an important step for understanding the distribution, function, and regulation of these receptors. A common approach for detecting proteins from complex biological systems is Western blotting. In this chapter, we describe a general approach to Western blotting protein components of the endocannabinoid system using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and nitrocellulose membranes, with a focus on detecting type 1 cannabinoid (CB1) receptors. When this technique is carefully used, specifically with validation of the primary antibodies, it can provide quantitative information on protein expression levels. Additional information can also be inferred from Western blotting such as potential posttranslational modifications that can be further evaluated by specific analytical techniques.

  7. Interrelationship of dietary lipids and ascorbic acid with hepatic enzymes of cholesterol metabolic pathway.

    Science.gov (United States)

    Sen, S; Mukherjee, S

    1997-01-01

    Effect of unsaturated and saturated fats on cholesterol metabolism was studied in ascorbate sufficient and deficient guineapigs. Experimental animals were made chronic ascorbic acid deficient by allowing oral intake of 0.5 mg ascorbic acid/day/animal. Elevation in serum and liver cholesterol and triglyceride along with depression in cholesterol oxidation and 7 alpha-hydroxylation in liver was observed in unsaturated fat fed guineapigs with ascorbate deficiency. Liver microsomal cytochrome P-450 level was found to be low in ascorbate deficient animals. Polyunsaturated fat intake could not lower the serum cholesterol level in ascorbate deficiency. Today polyunsaturated fat in the diet is encouraged all over the world for its hypocholesterolemic effect. This study indicates that polyunsaturated fat intake with ascorbic acid deficiency may produce hypercholesterolemia.

  8. 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

  9. Xenobiotic-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; Guth, K; Landsiedel, R

    2014-12-01

    The exposure of the skin to medical drugs, skin care products, cosmetics, and other chemicals renders information on xenobiotic-metabolizing enzymes (XME) in the skin highly interesting. Since the use of freshly excised human skin for experimental investigations meets with ethical and practical limitations, information on XME in models comes in the focus including non-human mammalian species and in vitro skin models. This review attempts to summarize the information available in the open scientific literature on XME in the skin of human, rat, mouse, guinea pig, and pig as well as human primary skin cells, human cell lines, and reconstructed human skin models. The most salient outcome is that much more research on cutaneous XME is needed for solid metabolism-dependent efficacy and safety predictions, and the cutaneous metabolism comparisons have to be viewed with caution. Keeping this fully in mind at least with respect to some cutaneous XME, some models may tentatively be considered to approximate reasonable closeness to human skin. For dermal absorption and for skin irritation among many contributing XME, esterase activity is of special importance, which in pig skin, some human cell lines, and reconstructed skin models appears reasonably close to human skin. With respect to genotoxicity and sensitization, activating XME are not yet judgeable, but reactive metabolite-reducing XME in primary human keratinocytes and several reconstructed human skin models appear reasonably close to human skin. For a more detailed delineation and discussion of the severe limitations see the "Overview and Conclusions" section in the end of this review.

  10. Blood selenium concentrations and enzyme activities related to glutathione metabolism in wild emperor geese

    Science.gov (United States)

    Franson, J. Christian; Hoffman, David J.; Schmutz, Joel A.

    2002-01-01

    In 1998, we collected blood samples from 63 emperor geese (Chen canagica) on their breeding grounds on the Yukon-Kuskokwim Delta (YKD) in western Alaska, USA. We studied the relationship between selenium concentrations in whole blood and the activities of glutathione peroxidase and glutathione reductase in plasma. Experimental studies have shown that plasma activities of these enzymes are useful biomarkers of selenium-induced oxidative stress, but little information is available on their relationship to selenium in the blood of wild birds. Adult female emperor geese incubating their eggs in mid-June had a higher mean concentration of selenium in their blood and a greater activity of glutathione peroxidase in their plasma than adult geese or goslings that were sampled during the adult flight feathermolting period in late July and early August. Glutathione peroxidase activity was positively correlated with the concentration of selenium in the blood of emperor geese, and the rate of increase relative to selenium was greater in goslings than in adults. The activity of glutathione reductase was greatest in the plasma of goslings and was greater in molting adults than incubating females but was not significantly correlated with selenium in the blood of adults or goslings. Incubating female emperor geese had high selenium concentrations in their blood, accompanied by increased glutathione peroxidase activity consistent with early oxidative stress. These findings indicate that further study of the effects of selenium exposure, particularly on reproductive success, is warranted in this species.

  11. Shared origins of a key enzyme during the evolution of C4 and CAM metabolism

    Science.gov (United States)

    Christin, Pascal-Antoine; Arakaki, Monica; Osborne, Colin P.; Bräutigam, Andrea; Sage, Rowan F.; Hibberd, Julian M.; Kelly, Steven; Covshoff, Sarah; Wong, Gane Ka-Shu; Hancock, Lillian; Edwards, Erika J.

    2014-01-01

    CAM and C4 photosynthesis are two key plant adaptations that have evolved independently multiple times, and are especially prevalent in particular groups of plants, including the Caryophyllales. We investigate the origin of photosynthetic PEPC, a key enzyme of both the CAM and C4 pathways. We combine phylogenetic analyses of genes encoding PEPC with analyses of RNA sequence data of Portulaca, the only plants known to perform both CAM and C4 photosynthesis. Three distinct gene lineages encoding PEPC exist in eudicots (namely ppc-1E1, ppc-1E2 and ppc-2), one of which (ppc-1E1) was recurrently recruited for use in both CAM and C4 photosynthesis within the Caryophyllales. This gene is present in multiple copies in the cacti and relatives, including Portulaca. The PEPC involved in the CAM and C4 cycles of Portulaca are encoded by closely related yet distinct genes. The CAM-specific gene is similar to genes from related CAM taxa, suggesting that CAM has evolved before C4 in these species. The similar origin of PEPC and other genes involved in the CAM and C4 cycles highlights the shared early steps of evolutionary trajectories towards CAM and C4, which probably diverged irreversibly only during the optimization of CAM and C4 phenotypes. PMID:24638902

  12. Effect of thyroid status on the expression of metabolic enzymes during chronic stimulation.

    Science.gov (United States)

    Hood, D A; Simoneau, J A; Kelly, A M; Pette, D

    1992-10-01

    The effect of thyroid status on the expression of cytochrome c oxidase (CYTOX) and the activities of citrate synthase (CS) and phosphofructokinase (PFK) were examined in chronically stimulated (10 Hz; 35 days) and contralateral, nonstimulated rat tibialis anterior muscle of hypothyroid, hyperthyroid, and euthyroid animals. Stimulation increased CYTOX activity by 2.7-, 3.2-, and 4.9-fold in hyperthyroid, euthyroid, and hypothyroid animals, respectively, to similar absolute values. CS displayed similar increases. Stimulation reduced PFK activity in hypothyroid and euthyroid animals to 45% and 60% of control values. This effect was abolished with hyperthyroidism. Thus stimulation and thyroid hormone act antagonistically on PFK activity. Stimulation increased CYTOX subunit III (mitochondrially encoded) mRNA by 2.5- and 2.9-fold in hyperthyroid and euthyroid animals. Similar increases were observed in the nuclear-encoded mRNAs of CYTOX subunit VIc in euthyroid muscle. In hyperthyroid and euthyroid conditions, the mRNA changes paralleled the increases in enzyme activity. In hypothyroid muscle, the increase in mRNA was less for subunit VIc than III, suggesting that hypothyroidism upsets the coordinate expression of nuclear and mitochondrial genes. Further, the increases in CYTOX activity exceeded that of both subunit mRNAs in hypothyroid muscle.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Changes in the Peripheral Endocannabinoid System as a Risk Factor for the Development of Eating Disorders.

    Science.gov (United States)

    Capasso, Anna; Milano, Walter; Cauli, Omar

    2018-02-12

    Eating Disorder (ED) is characterized by persistently and severely disturbed eating behaviours. They arise from a combination of long-standing behavioural, emotional, psychological, interpersonal, and social factors and result in insufficient nutrient ingestion and/or adsorption. The three main EDs are: anorexia nervosa, bulimia nervosa, and binge eating disorder. We review the role of peripheral endocannabinoids in eating behaviour. The neuronal pathways involved in feeding behaviours are closely related to catecholaminergic, serotoninergic and peptidergic systems. Accordingly, feeding is promoted by serotonin, dopamine, and prostaglandin and inhibited by neuropeptide Y, norepinephrine, GABA, and opioid peptides. The endocannabinoid system plays a role in EDs, and multiple lines of evidence indicate that the cannabinoid signalling system is a key modulatory factor of the activity in the brain areas involved in EDs as well as in reward processes. Besides their central role in controlling food behaviours, peripheral cannabinoids are also involved in regulating adipose tissue and insulin signalling as well as cell metabolism in peripheral tissues such as liver, pancreas, fatty tissue, and skeletal muscle. Altogether, these data indicate that peripheral cannabinoids can provide new therapeutic targets not only for EDs but also for metabolic disease. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  14. Geraniol Pharmacokinetics, Bioavailability and Its Multiple Effects on the Liver Antioxidant and Xenobiotic-Metabolizing Enzymes

    Directory of Open Access Journals (Sweden)

    Barbara Pavan

    2018-01-01

    Full Text Available Geraniol is a natural monoterpene showing anti-inflammatory, antioxidant, neuroprotective and anticancer effects. No pharmacokinetic and bioavailability data on geraniol are currently available. We therefore performed a systematic study to identify the permeation properties of geraniol across intestinal cells, and its pharmacokinetics and bioavailability after intravenous and oral administration to rats. In addition, we systematically investigated the potential hepatotoxic effects of high doses of geraniol on hepatic phase I, phase II and antioxidant enzymatic activities and undertook a hematochemical analysis on mice. Permeation studies performed via HPLC evidenced geraniol permeability coefficients across an in vitro model of the human intestinal wall for apical to basolateral and basolateral to apical transport of 13.10 ± 2.3 × 10-3 and 2.1 ± 0.1⋅× 10-3 cm/min, respectively. After intravenous administration of geraniol to rats (50 mg/kg, its concentration in whole blood (detected via HPLC decreased following an apparent pseudo-first order kinetics with a half-life of 12.5 ± 1.5 min. The absolute bioavailability values of oral formulations (50 mg/kg of emulsified geraniol or fiber-adsorbed geraniol were 92 and 16%, respectively. Following emulsified oral administration, geraniol amounts in the cerebrospinal fluid of rats ranged between 0.72 ± 0.08 μg/mL and 2.6 ± 0.2 μg/mL within 60 min. Mice treated with 120 mg/kg of geraniol for 4 weeks showed increased anti-oxidative defenses with no signs of liver toxicity. CYP450 enzyme activities appeared only slightly affected by the high dosage of geraniol.

  15. Immune system modulation in the central nervous system: A possible role for endocannabinoids

    International Nuclear Information System (INIS)

    Abd-Allah, Adel R.A.

    2007-01-01

    The immune system is designed to protect the body from infection and tumor formation. To perform this function, cells of the immune system can be dangerous for the survival and function of the neuronal network in the brain under the influence of infection or immune imbalance. An attack of immune cells inside the brain includes the potential for severe neuronal damage or cell death and therefore impairment of the CNS function. To avoid such undesirable action of the immune system, the CNS performs a cascade of cellular and molecular mechanisms enabling strict control of immune reactions i mmune privilege . Under inflammatory and patholological conditions, uncontrolled immune system results in the activation of neuronal damage that is frequently associated with neurological diseases. On the other hand, processes of neuroprotection and neurorepair after neuronal damage depend on a steady and tightly controlled immunesurvelliance. Many immunoprotectants play a role to imbalance the immune reactions in the CNS and other organs which presents an important therapeutic target. It has been reported recently that endocannabinoids are secreted in abundance in the CNS following neuronal insult, probably for its protection. There are at least two types of cannabinoid receptors, CB1 and CB2. Both are coupled to G proteins. CB1 receptors exist primarily on central and peripheral neurons. CB2 receptors are present mainly on immune cells. Endogenous agonists for cannabinoid receptors (endocannabinoids), have been discovered, the most important being arachidonoyl ethanolamide (anandamide), 2-arachidonoyl glycerol (2AG), and 2-archidonyl glyceryl ether. Following their release, endocannabinoids are removed from the extracellular space and then degraded by intracellular enzymic hydrolysis. Therapeutic uses of cannabinoid receptor agonists/antagonists include the management of many disease conditions. They are also involved in immune system suppression and in cell to cell communication

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Effects of lead nitrate on the activity of metabolic enzymes during early developmental stages of the African catfish, Clarias gariepinus (Burchell, 1822)

    NARCIS (Netherlands)

    Osman, A.G.M.; Mekkawy, Imam A.; Verreth, J.A.J.; Kirschbaum, Frank

    2007-01-01

    Glucose-6-phosphate dehydrogenase (G6PDH), lactate dehydrogenase (LDH) and pyruvate kinase (PK) are key metabolic enzymes. G6PDH has been used as a biomarker of pollution-induced carcinogenesis in fish. LDH has been used as marker of lesions in toxicology and clinical chemistry, and PK catalyses the

  18. Correlation-based network analysis of metabolite and enzyme profiles reveals a role of citrate biosynthesis in modulating N and C metabolism in zea mays

    Science.gov (United States)

    To investigate the natural variability of leaf metabolism and enzymatic activity in a maize inbred population, statistical and network analyses were employed on metabolite and enzyme profiles. The test of coefficient of variation showed that sugars and amino acids displayed opposite trends in their ...

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

    Czech Academy of Sciences Publication Activity Database

    Jammer, A.; Gapserl, A.; Luschin-Ebengreuth, N.; Heyneke, E.; Chu, H.; Cantero-Navarro, E.; Grosskinsky, D. K.; Albacete, A.; Stabentheiner, E.; Franzaring, J.; Fangmeier, A.; van der Graaff, E.; Roitsch, Thomas

    2015-01-01

    Roč. 66, č. 18 (2015), s. 5531-5542 ISSN 0022-0957 Institutional support: RVO:67179843 Keywords : Carbohydrate metabolism * dialysis * enzyme activities * kinetic assay * physiological phenotyping * physiological state * protein extraction * signatures Subject RIV: EH - Ecology, Behaviour Impact factor: 5.677, year: 2015

  20. Identification of human cytochrome P450 and UGT enzymes involved in the metabolism of ferulic acid, a major bioactive component in traditional Chinese medicines.

    Science.gov (United States)

    Zhuang, Xiao-Mei; Chen, Lin; Tan, Yan; Yang, Hai-Ying; Lu, Chuang; Gao, Yue; Li, Hua

    2017-09-01

    Ferulic acid (FA) is an active component of herbal medicines. One of the best documented activities of FA is its antioxidant property. Moreover, FA exerts antiallergic, anti-inflammatory, and hepatoprotective effects. However, the metabolic pathways of FA in humans remain unclear. To identify whether human CYP or UGT enzymes are involved in the metabolism of FA, reaction phenotyping of FA was conducted using major CYP-selective chemical inhibitors together with individual CYP and UGT Supersomes. The CYP- and/or UGT-mediated metabolism kinetics were examined simultaneously or individually. Relative activity factor and total normalized rate approaches were used to assess the relative contributions of each major human CYPs towards the FA metabolism. Incubations of FA with human liver microsomes (HLM) displayed NADPH- and UDPGA-dependent metabolism with multiple CYP and UGT isoforms involved. CYPs and UGTs contributed equally to the metabolism of FA in HLM. Although CYP1A2 and CYP3A4 appeared to be the major contributors in the CYP-mediated clearance, their contributions to the overall clearance are still minor (medicines because multiple phase I and phase II enzymes are involved in its metabolism. Copyright © 2017 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  1. Case-only study of interactions between metabolic enzymes and smoking in colorectal cancer

    International Nuclear Information System (INIS)

    Fan, Chunhong; Jin, Mingjuan; Chen, Kun; Zhang, Yongjing; Zhang, Shuangshuang; Liu, Bing

    2007-01-01

    Gene-gene and gene-environment interactions involved in the metabolism of carcinogens may increase the risk of cancer. Our objective was to measure the interactions between common polymorphisms of P450 (CYP1A2, CYP1B1, CYP2E1), GSTM1 and T1, SULT1A1 and cigarette smoking in colorectal cancer (CRC). A case-only design was conducted in a Chinese population including 207 patients with sporadic CRC. Unconditional logistic regression analysis was performed adjusting for age, gender, alcohol consumption, and cigarette smoking. The interaction odds ratio (COR) for the gene-gene interaction between CYP1B1 1294G and SULT1A1 638A allele was 2.68 (95% CI: 1.16–6.26). The results of the gene-environment analyses revealed that an interaction existed between cigarette smoking and the CYP1B1 1294G allele for CRC (COR = 2.62, 95%CI: 1.01–6.72), the COR for the interaction of CYP1B1 1294G and smoking history > 35 pack-years was 3.47 (95%CI: 1.12–10.80). No other significant gene-gene and gene-environment interactions were observed. Our results showed that the interaction between polymorphisms in CYP1B1 1294G and SULT1A1*2 may play a significant role on CRC in the Chinese population. Also, it is suggested that the association between cigarette smoking and CRC could be differentiated by the CYP1B1 1294G allele

  2. Cobalt deficiency effects on trace elements, hormones and enzymes involved in energy metabolism of cattle.

    Science.gov (United States)

    Stangl, G I; Schwarz, F J; Kirchgessner, M

    1999-03-01

    This study was conducted to investigate the physiological consequences of long-term moderate cobalt deficiency in beef cattle, which have not hitherto been studied in detail. Cobalt deficiency was induced in cattle by feeding two groups of animals either a basal corn silage-based diet that was moderately low in cobalt (83 micrograms Co/kg), or the same diet supplemented with cobalt to a total of 200 micrograms per kg, for 43 weeks. Cobalt deficiency was induced, as judged by inappetance, diminished growth gain and a markedly reduced vitamin B12 status in serum and liver. The long-term cobalt deprivation which was primarily a combination of reduced feed intake and a tissue vitamin B12 deficiency did not show evidence of a significant dysfunction of energy metabolism. The activities of glucose-6-phosphate dehydrogenase and cytochrome oxidase in liver remained unaffected by cobalt deficiency, nor was there a significant change in serum glucose level of cattle on the cobalt-deprived diet. However, analysis of thyroid hormone status indicated a slight reduction of type I thyroxine monodeiodinase activity in liver accompanied by a significant reduction of the triiodothyronine level in serum. The diminished liver vitamin B12 level resulted in significantly reduced folate level in this tissue, reduced concentrations of heme-depending blood parameters. Moreover cobalt deficiency or rather vitamin B12 deficiency was accompanied by a dramatic accumulation of the trace elements iron and nickel in liver. These results indicate that long-term moderate cobalt deficiency may induce a number of physiological changes in cattle, but a follow-up study, which excluded different feed levels by including a pair-fed control group, will be necessary to actually obtain the single effect of cobalt deficiency in cattle.

  3. Targeting the endocannabinoid/CB1 receptor system for treating obesity in Prader–Willi syndrome

    Directory of Open Access Journals (Sweden)

    Ibrahim Knani

    2016-12-01

    Full Text Available Objective: Extreme obesity is a core phenotypic feature of Prader–Willi syndrome (PWS. Among numerous metabolic regulators, the endocannabinoid (eCB system is critically involved in controlling feeding, body weight, and energy metabolism, and a globally acting cannabinoid-1 receptor (CB1R blockade reverses obesity both in animals and humans. The first-in-class CB1R antagonist rimonabant proved effective in inducing weight loss in adults with PWS. However, it is no longer available for clinical use because of its centrally mediated, neuropsychiatric, adverse effects. Methods: We studied eCB ‘tone’ in individuals with PWS and in the Magel2-null mouse model that recapitulates the major metabolic phenotypes of PWS and determined the efficacy of a peripherally restricted CB1R antagonist, JD5037 in treating obesity in these mice. Results: Individuals with PWS had elevated circulating levels of 2-arachidonoylglycerol and its endogenous precursor and breakdown ligand, arachidonic acid. Increased hypothalamic eCB ‘tone’, manifested by increased eCBs and upregulated CB1R, was associated with increased fat mass, reduced energy expenditure, and decreased voluntary activity in Magel2-null mice. Daily chronic treatment of obese Magel2-null mice and their littermate wild-type controls with JD5037 (3 mg/kg/d for 28 days reduced body weight, reversed hyperphagia, and improved metabolic parameters related to their obese phenotype. Conclusions: Dysregulation of the eCB/CB1R system may contribute to hyperphagia and obesity in Magel2-null mice and in individuals with PWS. Our results demonstrate that treatment with peripherally restricted CB1R antagonists may be an effective strategy for the management of severe obesity in PWS. Author Video: Author Video Watch what authors say about their articles Keywords: Endocannabinoids, PWS, Magel2, Peripheral CB1 blockade, Metabolic syndrome

  4. The effects of Ficus carica on the activity of enzymes related to metabolic syndrome

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    Ramgopal Mopuri

    2018-01-01

    Full Text Available The present study aimed to investigate the effects of the various parts of Ficus carica L. (figs on antioxidant, antidiabetic, and antiobesogenic effects in vitro. Fruit, leaves, and stembark of the F. carica plant were sequentially extracted using organic and inorganic solvents and their total polyphenol and flavonoid contents were estimated. The effects of the extracts on antioxidative, antidiabetic (inhibition of α-amylase and α-glucosidase enzymes, and antiobesogenic (antilipase activities were measured using several experimental models. The fruit ethanolic extract contained a high quantity of polyphenols and flavonoids (104.67±5.51 μg/mL and 81.67±4.00 μg/mL compared with all other extracts. The activity of the ethanolic extract of F. carica fruit was significantly (p<0.05 higher than all other extracts and parts of the plant in terms of antioxidative, antidiabetic, and antiobesogenic effects. The IC50 values of the fruit ethanolic extract in terms of antioxidative (134.44±18.43 μg/mL, and inhibition of α-glucosidase (255.57±36.46 μg/mL, α-amylase (315.89±3.83 μg/mL, and pancreatic lipase (230.475±9.65 μg/mL activity indicate that the activity of fruit ethanolic extract is better than all other extracts of the plant. The gas chromatography–mass spectroscopy analysis of the fruit ethanolic extract showed the presence of a number of bioactive compounds such as butyl butyrate, 5-hydroxymethyl furfural, 1-butoxy-1-isobutoxy butane, malic acid, tetradecanoic acid, phytol acetate, trans phytol, n-hexadecanoic acid, 9Z,12Z-octadecadienoic acid, stearic acid, sitosterol, 3,5-dihydroxy-6-methyl-2,3-dihydro-4H-pyran-4-one, and 2,4,5-trimethyl-2,4-dihydro-3H-pyrazol-3-one. The results of this study suggest that the ethanolic extract of the fruit of F. carica may have potential antidiabetic and antiobesogenic agents.

  5. Repeated homotypic stress elevates 2-arachidonoylglycerol levels and enhances short-term endocannabinoid signaling at inhibitory synapses in basolateral amygdala.

    Science.gov (United States)

    Patel, Sachin; Kingsley, Philip J; Mackie, Ken; Marnett, Lawrence J; Winder, Danny G

    2009-12-01

    Psychosocial stress is a risk factor for development and exacerbation of neuropsychiatric illness. Repeated stress causes biochemical adaptations in endocannabinoid (eCB) signaling that contribute to stress-response habituation, however, the synaptic correlates of these adaptations have not been examined. Here, we show that the synthetic enzyme for the eCB 2-arachidonoylglycerol (2-AG), diacylglycerol (DAG) lipase alpha, is heterogeneously expressed in the amygdala, and that levels of 2-AG and precursor DAGs are increased in the basolateral amygdala (BLA) after 10 days, but not 1 day, of restraint stress. In contrast, arachidonic acid was decreased after both 1 and 10 days of restraint stress. To examine the synaptic correlates of these alterations in 2-AG metabolism, we used whole-cell electrophysiology to determine the effects of restraint stress on depolarization-induced suppression of inhibition (DSI) in the BLA. A single restraint stress exposure did not alter DSI compared with control mice. However, after 10 days of restraint stress, DSI duration, but not magnitude, was significantly prolonged. Inhibition of 2-AG degradation with MAFP also prolonged DSI duration; the effects of repeated restraint stress and MAFP were mutually occlusive. These data indicate that exposure to repeated, but not acute, stress produces neuroadaptations that confer BLA neurons with an enhanced capacity to elevate 2-AG content and engage in 2-AG-mediated short-term retrograde synaptic signaling. We suggest stress-induced enhancement of eCB-mediated suppression of inhibitory transmission in the BLA could contribute to affective dysregulation associated with chronic stress.

  6. The administration of endocannabinoid uptake inhibitors OMDM-2 or VDM-11 promotes sleep and decreases extracellular levels of dopamine in rats.

    Science.gov (United States)

    Murillo-Rodríguez, Eric; Palomero-Rivero, Marcela; Millán-Aldaco, Diana; Di Marzo, Vincenzo

    2013-01-17

    The family of the endocannabinoid system comprises endogenous lipids (such as anandamide [ANA]), receptors (CB(1)/CB(2) cannabinoid receptors), metabolic enzymes (fatty acid amide hydrolase [FAAH]) and a putative membrane transporter (anandamide membrane transporter [AMT]). Although the role of ANA, FAAH or the CB(1) cannabinoid receptor in sleep modulation has been reported, the effects of the inhibition of AMT on sleep remain unclear. In the present study, we show that microdialysis perfusion in rats of AMT inhibitors, (9Z)-N-[1-((R)-4-hydroxbenzyl)-2-hydroxyethyl]-9-octadecenamide (OMDM-2) or N-(4-hydroxy-2-methylphenyl)-5Z,8Z,11Z,14Z-eicosatetraenamide (VDM-11; 10, 20 or 30 μM; each compound) delivered into the paraventricular thalamic nucleus (PVA) increased sleep and decreased waking. In addition, the infusion of compounds reduced the extracellular levels of dopamine collected from nucleus accumbens. Taken together, these findings illustrate a critical role of AMT in sleep modulation. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Adipose tissue endocannabinoid system gene expression: depot differences and effects of diet and exercise

    Directory of Open Access Journals (Sweden)

    Yang Rongze

    2011-10-01

    Full Text Available Abstract Background Alterations of endocannabinoid system in adipose tissue play an important role in lipid regulation and metabolic dysfunction associated with obesity. The purpose of this study was to determine whether gene expression levels of cannabinoid type 1 receptor (CB1 and fatty acid amide hydrolase (FAAH are different in subcutaneous abdominal and gluteal adipose tissue, and whether hypocaloric diet and aerobic exercise influence subcutaneous adipose tissue CB1 and FAAH gene expression in obese women. Methods Thirty overweight or obese, middle-aged women (BMI = 34.3 ± 0.8 kg/m2, age = 59 ± 1 years underwent one of three 20-week weight loss interventions: caloric restriction only (CR, N = 9, caloric restriction plus moderate-intensity aerobic exercise (CRM, 45-50% HRR, N = 13, or caloric restriction plus vigorous-intensity aerobic exercise (CRV, 70-75% HRR, N = 8. Subcutaneous abdominal and gluteal adipose tissue samples were collected before and after the interventions to measure CB1 and FAAH gene expression. Results At baseline, FAAH gene expression was higher in abdominal, compared to gluteal adipose tissue (2.08 ± 0.11 vs. 1.78 ± 0.10, expressed as target gene/β-actin mRNA ratio × 10-3, P Conclusions There are depot differences in subcutaneous adipose tissue endocannabinoid system gene expression in obese individuals. Aerobic exercise training may preferentially modulate abdominal adipose tissue endocannabinoid-related gene expression during dietary weight loss. Trial Registration ClinicalTrials.gov: NCT00664729.

  8. Enhanced activity of carbohydrate- and lipid-metabolizing enzymes in insecticide-resistant populations of the maize weevil, Sitophilus zeamais.

    Science.gov (United States)

    Araújo, R A; Guedes, R N C; Oliveira, M G A; Ferreira, G H

    2008-08-01

    Insecticide resistance is frequently associated with fitness disadvantages in the absence of insecticides. However, intense past selection with insecticides may allow the evolution of fitness modifier alleles that mitigate the cost of insecticide resistance and their consequent fitness disadvantages. Populations of Sitophilus zeamais with different levels of susceptibility to insecticides show differences in the accumulation and mobilization of energy reserves. These differences may allow S. zeamais to better withstand toxic compounds without reducing the beetles' reproductive fitness. Enzymatic assays with carbohydrate- and lipid-metabolizing enzymes were, therefore, carried out to test this hypothesis. Activity levels of trehalase, glycogen phosphorylase, lipase, glycosidase and amylase were determined in two insecticide-resistant populations showing (resistant cost) or not showing (resistant no-cost) associated fitness cost, and in an insecticide-susceptible population. Respirometry bioassays were also carried out with these weevil populations. The resistant no-cost population showed significantly higher body mass and respiration rate than the other two populations, which were similar. No significant differences in glycogen phosphorylase and glycosidase were observed among the populations. Among the enzymes studied, trehalase and lipase showed higher activity in the resistant cost population. The results obtained in the assays with amylase also indicate significant differences in activity among the populations, but with higher activity in the resistant no-cost population. The inverse activity trends of lipases and amylases in both resistant populations, one showing fitness disadvantage without insecticide exposure and the other not showing it, may underlay the mitigation of insecticide resistance physiological costs observed in the resistant no-cost population. The higher amylase activity observed in the resistant no-cost population may favor energy storage

  9. Activities of fructan- and sucrose-metabolizing enzymes in wheat stems subjected to water stress during grain filling.

    Science.gov (United States)

    Yang, Jianchang; Zhang, Jianhua; Wang, Zhiqing; Zhu, Qingsen; Liu, Lijun

    2004-12-01

    This study investigated if a controlled water deficit during grain filling of wheat (Triticum aestivum L.) could accelerate grain filling by facilitating the remobilization of carbon reserves in the stem through regulating the enzymes involved in fructan and sucrose metabolism. Two high lodging-resistant wheat cultivars were grown in pots and treated with either a normal (NN) or high amount of nitrogen (HN) at heading time. Plants were either well-watered (WW) or water-stressed (WS) from 9 days post anthesis until maturity. Leaf water potentials markedly decreased at midday as a result of water stress but completely recovered by early morning. Photosynthetic rate and zeatin + zeatin riboside concentrations in the flag leaves declined faster in WS plants than in WW plants, and they decreased more slowly with HN than with NN when soil water potential was the same, indicating that the water deficit enhanced, whereas HN delayed, senescence. Water stress, both at NN and HN, facilitated the reduction in concentration of total nonstructural carbohydrates (NSC) and fructans in the stems but increased the sucrose level there, promoted the re-allocation of pre-fixed (14)C from the stems to grains, shortened the grain-filling period, and accelerated the grain-filling rate. Grain weight and grain yield were increased under the controlled water deficit when HN was applied. Fructan exohydrolase (FEH; EC 3.2.1.80) and sucrose phosphate synthase (SPS; EC 2.4.1.14) activities were substantially enhanced by water stress and positively correlated with the total NSC and fructan remobilization from the stems. Acid invertase (EC 3.2.1.26) activity was also enhanced by the water stress and associated with the change in fructan concentration, but not correlated with the total NSC remobilization and (14)C increase in the grains. Sucrose:sucrose fructosyltransferase (EC 2.4.1.99) activity was inhibited by the water stress and negatively correlated with the remobilization of carbon reserves

  10. Toxicity of Xanthene Food Dyes by Inhibition of Human Drug-Metabolizing Enzymes in a Noncompetitive Manner

    International Nuclear Information System (INIS)

    Mizutani, T.

    2010-01-01

    The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the non inhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of O 12 originating on xanthene dyes by light irradiation, because inhibition was prevented by O 12 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin.

  11. Toxicity of xanthene food dyes by inhibition of human drug-metabolizing enzymes in a noncompetitive manner.

    Science.gov (United States)

    Mizutani, Takaharu

    2009-01-01

    The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC(50) values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC(50) values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of (1)O(2) originating on xanthene dyes by light irradiation, because inhibition was prevented by (1)O(2) quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin.

  12. Toxicity of Xanthene Food Dyes by Inhibition of Human Drug-Metabolizing Enzymes in a Noncompetitive Manner

    Science.gov (United States)

    Mizutani, Takaharu

    2009-01-01

    The synthetic food dyes studied were rose bengal (RB), phroxine (PL), amaranth, erythrosine B (ET), allura red, new coccine, acid red (AR), tartrazine, sunset yellow FCF, brilliant blue FCF, and indigo carmine. First, data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. ET inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). We showed the inhibitory effect of xanthene dye on human UGT1A6 activity. Basic ET, PL, and RB in those food dyes strongly inhibited UGT1A6 activity, with IC50 values = 0.05, 0.04, and 0.015 mM, respectively. Meanwhile, AR of an acidic xanthene food dye showed no inhibition. Next, we studied the inhibition of CYP3A4 of a major phase I drug-metabolizing enzyme and P-glycoprotein of a major transporter by synthetic food dyes. Human CYP3A4 and P-glycoprotein were also inhibited by basic xanthene food dyes. The IC50 values of these dyes to inhibit CYP3A4 and P-glycoprotein were the same as the inhibition level of UGT1A6 by three halogenated xanthene food dyes (ET, PL, and RB) described above, except AR, like the results with UGT1A6 and UGT2B7. We also confirmed the noninhibition of CYP3A4 and P-gp by other synthetic food dyes. Part of this inhibition depended upon the reaction of 1O2 originating on xanthene dyes by light irradiation, because inhibition was prevented by 1O2 quenchers. We studied the influence of superoxide dismutase and catalase on this inhibition by dyes and we found prevention of inhibition by superoxide dismutase but not catalase. This result suggests that superoxide anions, originating on dyes by light irradiation, must attack drug-metabolizing enzymes. It is possible that red cosmetics containing phloxine, erythrosine, or rose bengal react with proteins on skin under lighting and may lead to rough skin. PMID:20041016

  13. Coactivator PGC-1α regulates the fasting inducible xenobiotic-metabolizing enzyme CYP2A5 in mouse primary hepatocytes

    International Nuclear Information System (INIS)

    Arpiainen, Satu; Jaervenpaeae, Sanna-Mari; Manninen, Aki; Viitala, Pirkko; Lang, Matti A.; Pelkonen, Olavi; Hakkola, Jukka

    2008-01-01

    The nutritional state of organisms and energy balance related diseases such as diabetes regulate the metabolism of xenobiotics such as drugs, toxins and carcinogens. However, the mechanisms behind this regulation are mostly unknown. The xenobiotic-metabolizing cytochrome P450 (CYP) 2A5 enzyme has been shown to be induced by fasting and by glucagon and cyclic AMP (cAMP), which mediate numerous fasting responses. Peroxisome proliferator-activated receptor γ coactivator (PGC)-1α triggers many of the important hepatic fasting effects in response to elevated cAMP levels. In the present study, we were able to show that cAMP causes a coordinated induction of PGC-1α and CYP2A5 mRNAs in murine primary hepatocytes. Furthermore, the elevation of the PGC-1α expression level by adenovirus mediated gene transfer increased CYP2A5 transcription. Co-transfection of Cyp2a5 5' promoter constructs with the PGC-1α expression vector demonstrated that PGC-1α is able to activate Cyp2a5 transcription through the hepatocyte nuclear factor (HNF)-4α response element in the proximal promoter of the Cyp2a5 gene. Chromatin immunoprecipitation assays showed that PGC-1α binds, together with HNF-4α, to the same region at the Cyp2a5 proximal promoter. In conclusion, PGC-1α mediates the expression of CYP2A5 induced by cAMP in mouse hepatocytes through coactivation of transcription factor HNF-4α. This strongly suggests that PGC-1α is the major factor mediating the fasting response of CYP2A5

  14. Effects of atorvastatin metabolites on induction of drug-metabolizing enzymes and membrane transporters through human pregnane X receptor

    Science.gov (United States)

    Hoffart, E; Ghebreghiorghis, L; Nussler, AK; Thasler, WE; Weiss, TS; Schwab, M; Burk, O

    2012-01-01

    BACKGROUND AND PURPOSE Atorvastatin metabolites differ in their potential for drug interaction because of differential inhibition of drug-metabolizing enzymes and transporters. We here investigate whether they exert differential effects on the induction of these genes via activation of pregnane X receptor (PXR) and constitutive androstane receptor (CAR). EXPERIMENTAL APPROACH Ligand binding to PXR or CAR was analysed by mammalian two-hybrid assembly and promoter/reporter gene assays. Additionally, surface plasmon resonance was used to analyse ligand binding to CAR. Primary human hepatocytes were treated with atorvastatin metabolites, and mRNA and protein expression of PXR-regulated genes was measured. Two-hybrid co-activator interaction and co-repressor release assays were utilized to elucidate the molecular mechanism of PXR activation. KEY RESULTS All atorvastatin metabolites induced the assembly of PXR and activated CYP3A4 promoter activity. Ligand binding to CAR could not be proven. In primary human hepatocytes, the para-hydroxy metabolite markedly reduced or abolished induction of cytochrome P450 and transporter genes. While significant differences in co-activator recruitment were not observed, para-hydroxy atorvastatin demonstrated only 50% release of co-repressors. CONCLUSIONS AND IMPLICATIONS Atorvastatin metabolites are ligands of PXR but not of CAR. Atorvastatin metabolites demonstrate differential induction of PXR target genes, which results from impaired release of co-repressors. Consequently, the properties of drug metabolites have to be taken into account when analysing PXR-dependent induction of drug metabolism and transport. The drug interaction potential of the active metabolite, para-hydroxy atorvastatin, might be lower than that of the parent compound. PMID:21913896

  15. Low temperature and defoliation affect fructan-metabolizing enzymes in different regions of the rhizophores of Vernonia herbacea.

    Science.gov (United States)

    Portes, Maria Teresa; Figueiredo-Ribeiro, Rita de Cássia L; de Carvalho, Maria Angela M

    2008-10-09

    In addition to the storage function, fructans in Asteraceae from floras with seasonal growth have been associated with drought and freezing tolerance. Vernonia herbacea, native of the Brazilian Cerrado, bears underground reserve organs, rhizophores, accumulating inulin-type fructans. The rhizophore is a cauline branched system with positive geotropic growth, with the apex (distal region) presenting younger tissues; sprouting of new shoots occurs by development of buds located on the opposite end (proximal region). Plants induced to sprouting by excision of the aerial organs present increased 1-fructan exohydrolase (1-FEH) activity in the proximal region, while plants at the vegetative stage present high 1-sucrose:sucrose fructosyltransferase (1-SST) in the distal region. The aim of the present study was to analyze how low temperature (5 degrees C) could affect fructan-metabolizing enzymes and fructan composition in the different regions of the rhizophores of intact and excised plants. 1-SST and 1-fructan:fructan fructosyltransferase (1-FFT) were higher in the distal region decreasing towards the proximal region in intact plants at the vegetative phase, and were drastically diminished when cold and/or excision were imposed. In contrast, 1-FEH increased in the proximal region of treated plants, mainly in excised plants subjected to cold. The ratio fructo-oligo to fructo-polysaccharides was significantly higher in plants exposed to low temperature (1.17 in intact plants and 1.64 in excised plants) than in plants exposed to natural temperature conditions (0.84 in intact vegetative plants and 0.58 in excised plants), suggesting that oligosaccharides are involved in the tolerance of plants to low temperature via 1-FEH, in addition to 1-FFT. Principal component analysis indicated different response mechanisms in fructan metabolism under defoliation and low temperature, which could be interpreted as part of the strategies to undergo unfavorable environmental conditions

  16. Effects of dietary phospholipid level in cobia (Rachycentron canadum) larvae: growth, survival, plasma lipids and enzymes of lipid metabolism.

    Science.gov (United States)

    Niu, J; Liu, Y J; Tian, L X; Mai, K S; Yang, H J; Ye, C X; Zhu, Y

    2008-03-01

    A study was conducted to determine the effects of dietary phospholipid (PL) levels in cobia (Rachycentron canadum) larvae with regard to growth, survival, plasma lipids and enzymes of lipid metabolism. Fish with an average weight of 0.4 g were fed diets containing four levels of PL (0, 20, 40 and 80 g kg(-1)dry matter: purity 97%) for 42 days. Final body weight (FBW), weight gain (WG) and survival ratio were highest in the 8% PL diet group and mortality was highest in PL-free diet group. We examined the activities of lipoprotein lipase (LPL) and hepatic lipase (HL) in liver, lecithin-cholesterolacyltransferase (LCAT) in plasma as well as plasma lipids and lipoprotein. LCAT activity showed a decrease of more than two-fold in PL-supplemented diet groups compared with the PL-free diet group. HL activity was highest in the 8% PL diet group and the other three groups showed no difference. LPL activity was significantly higher in the PL-supplemented diet groups than in the PL-free diet group. The dietary intervention significantly increased plasma phospholipids and total cholesterol (TC) levels, and the higher free cholesterol (FC) level contributed to the TC level. However, the fish fed PL exhibited a significantly decreased plasma triglyceride (TG) level. The lipoprotein fractions were also affected significantly by the PL. The PL-supplemented diet groups had significantly higher high-density lipoprotein (HDL) compared with the PL-free diet group, but showed a marked decrease in very low-density lipoprotein (VLDL). The results suggested that PL could modify plasma lipoprotein metabolism and lipid profile, and that the optimal dietary PL level may well exceed 80 g kg(-1) for cobia larvae according to growth and survival.

  17. Association of CNR1 and FAAH endocannabinoid gene polymorphisms with anorexia nervosa and bulimia nervosa: evidence for synergistic effects.

    Science.gov (United States)

    Monteleone, P; Bifulco, M; Di Filippo, C; Gazzerro, P; Canestrelli, B; Monteleone, F; Proto, M C; Di Genio, M; Grimaldi, C; Maj, M

    2009-10-01

    Endocannabinoids modulate eating behavior; hence, endocannabinoid genes may contribute to the biological vulnerability to eating disorders. The rs1049353 (1359 G/A) single nucleotide polymorphism (SNP) of the gene coding the endocannabinoid CB1 receptor (CNR1) and the rs324420 (cDNA 385C to A) SNP of the gene coding fatty acid amide hydrolase (FAAH), the major degrading enzyme of endocannabinoids, have been suggested to have functional effects on mature proteins. Therefore, we explored the possibility that those SNPs were associated to anorexia nervosa and/or bulimia nervosa. The distributions of the CNR1 1359 G/A SNP and of the FAAH cDNA 385C to A SNP were investigated in 134 patients with anorexia nervosa, 180 patients with bulimia nervosa and 148 normal weight healthy controls. Additive effects of the two SNPs in the genetic susceptibility to anorexia nervosa and bulimia nervosa were also tested. As compared to healthy controls, anorexic and bulimic patients showed significantly higher frequencies of the AG genotype and the A allele of the CNR1 1359 G/A SNP. Similarly, the AC genotype and the A allele of the FAAH cDNA 385C to A SNP were significantly more frequent in anorexic and bulimic individuals. A synergistic effect of the two SNPs was evident in anorexia nervosa but not in bulimia nervosa. Present findings show for the first time that the CNR1 1359 G/A SNP and the FAAH cDNA 385C to A SNP are significantly associated to anorexia nervosa and bulimia nervosa, and demonstrate a synergistic effect of the two SNPs in anorexia nervosa.

  18. FEMALE MICE ARE RESISTANT TO Fabp1 GENE ABLATION-INDUCED ALTERATIONS IN BRAIN ENDOCANNABINOID LEVELS

    Science.gov (United States)

    Martin, Gregory G.; Chung, Sarah; Landrock, Danilo; Landrock, Kerstin K.; Dangott, Lawrence J.; Peng, Xiaoxue; Kaczocha, Martin; Murphy, Eric J.; Kier, Ann B.; Schroeder, Friedhelm

    2017-01-01

    Although liver fatty acid binding protein (FABP1, L-FABP) is not detectable in brain, Fabp1 gene ablation (LKO) markedly increases endocannabinoids (EC) in brains of male mice. Since the brain EC system of females differs significantly from that of males, it was important to determine if LKO differently impacted the brain EC system. LKO did not alter brain levels of arachidonic acid (ARA)-containing ECs, i.e arachidonoylethanolamide (AEA) and 2-arachidonoylglycerol (2-AG), but decreased non-ARA-containing N-acylethanolamides (OEA, PEA) and 2-oleoylglycerol (2-OG) that potentiate the actions of AEA and 2-AG. These changes in brain potentiating EC levels were not associated with: i) a net decrease in levels of brain membrane proteins associated with fatty acid uptake and EC synthesis; ii) a net increase in brain protein levels of cytosolic EC chaperones and enzymes in EC degradation; or iii) increased brain protein levels of EC receptors (CB1, TRVP1). Instead, the reduced or opposite responsiveness of female brain EC levels to loss of FABP1 (LKO) correlated with intrinsically lower FABP1 level in livers of WT females than males. These data show that female mouse brain endocannabinoid levels were unchanged (AEA, 2-AG) or decreased (OEA, PEA, 2-OG) by complete loss of FABP1 (LKO). PMID:27450559

  19. Effects of the antipsychotic paliperidone on stress-induced changes in the endocannabinoid system in rat prefrontal cortex.

    Science.gov (United States)

    MacDowell, Karina S; Sayd, Aline; García-Bueno, Borja; Caso, Javier R; Madrigal, José L M; Leza, Juan Carlos

    2017-09-01

    Objectives There is a need to explore novel mechanisms of action of existing/new antipsychotics. One potential candidate is the endocannabinoid system (ECS). The present study tried to elucidate the effects of the antipsychotic paliperidone on stress-induced ECS alterations. Methods Wister rats were submitted to acute/chronic restraint stress. Paliperidone (1 mg/kg) was given prior each stress session. Cannabinoid receptors and endocannabinoids (eCBs) synthesis and degradation enzymes were measured in prefrontal cortex (PFC) samples by RT-PCR and Western Blot. Results In the PFC of rats exposed to acute stress, paliperidone increased CB1 receptor (CB1R) expression. Furthermore, paliperidone increased the expression of the eCB synthesis enzymes N-acylphosphatidylethanolamine- hydrolysing phospholipase D and DAGLα, and blocked the stress-induced increased expression of the degrading enzyme fatty acid amide hydrolase. In chronic conditions, paliperidone prevented the chronic stress-induced down-regulation of CB1R, normalised DAGLα expression and reverted stress-induced down-regulation of the 2-AG degrading enzyme monoacylglycerol lipase. ECS was analysed also in periphery. Acute stress decreased DAGLα expression, an effect prevented by paliperidone. Contrarily, chronic stress increased DAGLα and this effect was potentiated by paliperidone. Conclusions The results obtained described a preventive effect of paliperidone on stress-induced alterations in ECS. Considering the diverse alterations on ECS described in psychotic disease, targeting ECS emerges as a new therapeutic possibility.

  20. Comprehensive functional characterization of the glycoside hydrolase family 3 enzymes from Cellvibrio japonicus reveals unique metabolic roles in biomass saccharification.

    Science.gov (United States)

    Nelson, Cassandra E; Attia, Mohamed A; Rogowski, Artur; Morland, Carl; Brumer, Harry; Gardner, Jeffrey G

    2017-12-01

    Lignocellulose degradation is central to the carbon cycle and renewable biotechnologies. The xyloglucan (XyG), β(1→3)/β(1→4) mixed-linkage glucan (MLG) and β(1→3) glucan components of lignocellulose represent significant carbohydrate energy sources for saprophytic microorganisms. The bacterium Cellvibrio japonicus has a robust capacity for plant polysaccharide degradation, due to a genome encoding a large contingent of Carbohydrate-Active enZymes (CAZymes), many of whose specific functions remain unknown. Using a comprehensive genetic and biochemical approach, we have delineated the physiological roles of the four C. japonicus glycoside hydrolase family 3 (GH3) members on diverse β-glucans. Despite high protein sequence similarity and partially overlapping activity profiles on disaccharides, these β-glucosidases are not functionally equivalent. Bgl3A has a major role in MLG and sophorose utilization, and supports β(1→3) glucan utilization, while Bgl3B underpins cellulose utilization and supports MLG utilization. Bgl3C drives β(1→3) glucan utilization. Finally, Bgl3D is the crucial β-glucosidase for XyG utilization. This study not only sheds the light on the metabolic machinery of C. japonicus, but also expands the repertoire of characterized CAZymes for future deployment in biotechnological applications. In particular, the precise functional analysis provided here serves as a reference for informed bioinformatics on the genomes of other Cellvibrio and related species. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  1. The expression of xenobiotic-metabolizing enzymes in human prostate and in prostate epithelial cells (PECs) derived from primary cultures.

    Science.gov (United States)

    Al-Buheissi, S Z; Cole, K J; Hewer, A; Kumar, V; Bryan, R L; Hudson, D L; Patel, H R; Nathan, S; Miller, R A; Phillips, D H

    2006-06-01

    Dietary heterocyclic amines (HCAs) are carcinogenic in rodent prostate requiring activation by enzymes such as cytochrome P450 (CYP) and N-acetyltransferase (NAT). We investigated by Western blotting and immunohistochemistry the expression of CYP1A1, CYP1A2, and NAT1 in human prostate and in prostate epithelial cells (PECs) derived from primary cultures and tested their ability to activate the dietary carcinogen 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and its N-hydroxy metabolite (N-OH-IQ) to DNA-damaging moieties. Western blotting identified CYP1A1, CYP1A2, and NAT1. Immunohistochemistry localized NAT1 to the cytoplasm of PECs. Inter-individual variation was observed in the expression levels of CYP1A1, 1A2, and NAT1 (11, 75, and 35-fold, respectively). PECs expressed CYP1A1 and NAT1 but not CYP1A2. When incubated with IQ or N-OH-IQ, PECs formed DNA adducts indicating their ability to metabolically activate these compounds. Prostate cells possess the capacity to activate dietary carcinogens. PECs may provide a useful model system to study their role in prostate carcinogenesis.

  2. Investigation of the role of the enzymes of xenobiotic metabolism in the resistance of insects to insecticides

    International Nuclear Information System (INIS)

    Leonova, I.N.; Nedel'kina, S.V.; Naumova, N.B.; Salganik, R.I.

    1986-01-01

    The activity of three enzyme systems of xenobiotic metabolism: cytochrome P-450-dependent monooxygenases, nonspecific esterases, and glutathione S-transferases, was investigated on a sensitive strain (S) of the housefly M. domestica L. and strains resistant to tetrametrin (R/sub tetr/), permetrin (R/sub perm/), mecarbenyl (R/sub mec/), and chlorophos (R/sub chlor/). In the strains R/sub tetr/ and R/sub mec/, in comparison with strain S, an increase of 2.7 and 2.3-fold, respectively, in the activity of microsomal monooxygenases was observed. The position of the maxima of the CO-differential spectra of cytochrome P-450 in all the investigated resistant strains, with the exception of R/sub chlor/, is shifted by 1-2 nm in the shortwave direction. The activity of glutathione S-transferases in the strain R/sub tetr/ proved elevated in comparison with the strain S. The data of an investigation of the total esterase activity and the data of starch gel electrophoresis are evidence of quantitative and qualitative differences between the strains. For all the resistant strains except for R/sub mec/, supplementary zones of esterase activity appear. The data obtained are discussed in connection with the resistance of the insects to insecticides

  3. The distribution of 3H-(+-)noradrenaline in rabbit aortic strips after inhibition of the noradrenaline-metabolizing enzymes

    International Nuclear Information System (INIS)

    Henseling, M.; Eckert, E.; Trendelenburg, U.

    1976-01-01

    Rabbit aortic strips (nerve-free, reserpine pretreated or normal) whose noradrenaline-metabolizing enzymes were inhibited (by in vitro treatment with 0.5 mM pargyline for 30 min and by the presence of 0.1 mM U-0521) were exposed to 1.18 μM 3 H-(+-)noradrenaline for 30 min (in most experiments). At the end of the incubation some strips were used for anlysis of radioactivity (i.e., of noradrenaline and its metabolites), while for others the efflux of radioactivity was determined during 240 min of wash out with amine-free solution. An estimate of the original distribution of the amine into the various extraneuronal and neuronal compartments of the tissue was obtained by compartmental analysis of the efflux curves. Extracellular amine distributes into 'compartment I + II' (characterized by a half time for efflux of 14 C-sorbitol. The extraneuronal accumulation of noradrenaline is a quickly equilibrating process which involves compartments III and IV (with half times for efflux of 3 and 11 min, respectively). Compartment IV represents not only extraneuronally but also neuronally distributed noradrenaline. The neuronal accumulation of noradrenaline is a slowly equilibrating process which can be subdivided into axoplasmic and vesicular accumulation. The results support the view that the rate of relaxation (of strips initially exposed to noradrenaline and then washed out) is affected by the efflux of unchanged amine form extraneuronal and neuronal stores. (orig./GSE) [de

  4. Comprehensive functional characterization of the Glycoside Hydrolase Family 3 enzymes from Cellvibrio japonicus reveals unique metabolic roles in biomass saccharification

    International Nuclear Information System (INIS)

    Nelson, Cassandra E.; Attia, Mohamed A.; Rogowski, Artur; Morland, Carl; Brumer, Harry; Gardner, Jeffrey G.

    2017-01-01

    Here, lignocellulose degradation is central to the carbon cycle and renewable biotechnologies. The xyloglucan (XyG), β(1!3)/β(1!4) mixed-linkage glucan (MLG), and β(1!3) glucan components of lignocellulose represent significant carbohydrate energy sources for saprophytic microorganisms. The bacterium Cellvibrio japonicus has a robust capacity for plant polysaccharide degradation, due to a genome encoding a large contingent of Carbohydrate-Active Enzymes (CAZymes), many of whose specific functions remain unknown. Using a comprehensive genetic and biochemical approach we have delineated the physiological roles of the four C. japonicus Glycoside Hydrolase Family 3 (GH3) members on diverse β-glucans. Despite high protein sequence similarity and partially overlapping activity profiles on disaccharides, these β-glucosidases are not functionally equivalent. Bgl3A has a major role in MLG and sophorose utilization, and supports β(1!3) glucan utilization, while Bgl3B underpins cellulose utilization and supports MLG utilization. Bgl3C drives β(1!3) glucan utilization. Finally, Bgl3D is the crucial β-glucosidase for XyG utilization. This study not only sheds the light on the metabolic machinery of C. japonicus, but also expands the repertoire of characterized CAZymes for future deployment in biotechnological applications. In particular, the precise functional analysis provided here serves as a reference for informed bioinformatics on the genomes of other Cellvibrio and related species.

  5. Genetic polymorphisms of drug-metabolizing cytochrome P450 enzymes in cynomolgus and rhesus monkeys and common marmosets in preclinical studies for humans.

    Science.gov (United States)

    Uno, Yasuhiro; Uehara, Shotaro; Yamazaki, Hiroshi

    2017-12-23

    Cynomolgus monkeys (Macaca fascicularis, Old World Monkeys) and common marmosets (Callithrix jacchus, New World Monkeys) have been widely, and expectedly, used as non-human primate models in drug development studies. Major drug-metabolizing cytochrome P450 (P450) enzymes information is now available that supports these primate species as animal models, and it is established that multiple forms of cynomolgus monkey and common marmoset P450 enzymes have generally similar substrate recognition functionality to human P450 enzymes. This research update provides information on genetic polymorphisms of P450 enzymes in cynomolgus monkey and common marmoset like human P450 enzymes. Information on rhesus monkeys (Macaca mulatta), another macaque species used in drug metabolism studies, is also included for comparison. Among a variety of cynomolgus monkey P450 variants investigated, typical examples include individual pharmacokinetic data for efavirenz and R-warfarin associated with cynomolgus monkey P450 2C9 (formerly 2C43) and 2C19 (2C75) variants, respectively, and for R-omeprazole and S-warfarin associated with marmoset P450 2C19 variants. These findings provide a foundation for understanding the individual pharmacokinetic and toxicological results in non-human primates as preclinical models and will help to further support understanding of molecular mechanisms of human P450 function. In addition to these polymorphic P450 enzymes, effects of aging on some drug clearances mediated by cynomolgus monkey and common marmoset P450 enzymes were found in elder animals or animals pretreated with rifampicin. This review describes genetic and acquired individual differences in cynomolgus monkey and common marmoset P450 enzymes involved in drug oxidation associated with pharmacological and/or toxicological effects. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Distribution and phylogenies of enzymes of the Embden-Meyerhof-Parnas pathway from archaea and hyperthermophilic bacteria support a gluconeogenic origin of metabolism

    Directory of Open Access Journals (Sweden)

    Ron S. Ronimus

    2003-01-01

    Full Text Available Enzymes of the gluconeogenic/glycolytic pathway (the Embden-Meyerhof-Parnas (EMP pathway, the reductive tricarboxylic acid cycle, the reductive pentose phosphate cycle and the Entner-Doudoroff pathway are widely distributed and are often considered to be central to the origins of metabolism. In particular, several enzymes of the lower portion of the EMP pathway (the so-called trunk pathway, including triosephosphate isomerase (TPI; EC 5.3.1.1, glyceraldehyde-3-phosphate dehydrogenase (GAPDH; EC 1.2.1.12/13, phosphoglycerate kinase (PGK; EC 2.7.2.3 and enolase (EC 4.2.1.11, are extremely well conserved and universally distributed among the three domains of life. In this paper, the distribution of enzymes of gluconeogenesis/glycolysis in hyperthermophiles—microorganisms that many believe represent the least evolved organisms on the planet—is reviewed. In addition, the phylogenies of the trunk pathway enzymes (TPIs, GAPDHs, PGKs and enolases are examined. The enzymes catalyzing each of the six-carbon transformations in the upper portion of the EMP pathway, with the possible exception of aldolase, are all derived from multiple gene sequence families. In contrast, single sequence families can account for the archaeal and hyperthermophilic bacterial enzyme activities of the lower portion of the EMP pathway. The universal distribution of the trunk pathway enzymes, in combination with their phylogenies, supports the notion that the EMP pathway evolved in the direction of gluconeogenesis, i.e., from the bottom up.

  7. Responses of peripheral endocannabinoids and endocannabinoid-related compounds to hedonic eating in obesity.

    Science.gov (United States)

    Monteleone, A M; Di Marzo, V; Monteleone, P; Dalle Grave, R; Aveta, T; Ghoch, M El; Piscitelli, F; Volpe, U; Calugi, S; Maj, M

    2016-06-01

    Hedonic eating occurs independently from homeostatic needs prompting the ingestion of pleasurable foods that are typically rich in fat, sugar and/or salt content. In normal weight healthy subjects, we found that before hedonic eating, plasma levels of 2-arachidonoylglycerol (2-AG) were higher than before nonhedonic eating, and although they progressively decreased after food ingestion in both eating conditions, they were significantly higher in hedonic eating. Plasma levels of anandamide (AEA), oleoylethanolamide (OEA) and palmitoylethanolamide (PEA), instead, progressively decreased in both eating conditions without significant differences. In this study, we investigated the responses of AEA, 2-AG, OEA and PEA to hedonic eating in obese individuals. Peripheral levels of AEA, 2-AG, OEA and PEA were measured in 14 obese patients after eating favourite (hedonic eating) and non-favourite (nonhedonic eating) foods in conditions of no homeostatic needs. Plasma levels of 2-AG increased after eating the favourite food, whereas they decreased after eating the non-favourite food, with the production of the endocannabinoid being significantly enhanced in hedonic eating. Plasma levels of AEA decreased progressively in nonhedonic eating, whereas they showed a decrease after the exposure to the favourite food followed by a return to baseline values after eating it. No significant differences emerged in plasma OEA and PEA responses to favourite and non-favourite food. Present findings compared with those obtained in our previously studied normal weight healthy subjects suggest deranged responses of endocannabinoids to food-related reward in obesity.

  8. 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.

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

    Science.gov (United States)

    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.

  10. Protective Effect of Free and Bound Polyphenol Extracts from Ginger (Zingiber officinale Roscoe on the Hepatic Antioxidant and Some Carbohydrate Metabolizing Enzymes of Streptozotocin-Induced Diabetic Rats

    Directory of Open Access Journals (Sweden)

    Mutiu Idowu Kazeem

    2013-01-01

    Full Text Available This study investigated the hepatoprotective effects of polyphenols from Zingiber officinale on streptozotocin-induced diabetic rats by assessing liver antioxidant enzymes, carbohydrate-metabolizing enzymes and liver function indices. Initial oral glucose tolerance test was conducted using 125 mg/kg, 250 mg/kg, and 500 mg/kg body weight of both free and bound polyphenols from Z. officinale. 28 day daily oral administration of 500 mg/kg body weight of free and bound polyphenols from Z. officinale to streptozotocin-induced (50 mg/kg diabetic rats significantly reduced (P<0.05 the fasting blood glucose compared to control groups. There was significant increase (P<0.05 in the antioxidant enzymes activities in the animals treated with both polyphenols. Similarly, the polyphenols normalised the activities of some carbohydrate metabolic enzymes (hexokinase and phosphofructokinase in the liver of the rats treated with it and significantly reduced (P<0.05 the activities of liver function enzymes. The results from the present study have shown that both free and bound polyphenols from Z. officinale especially the free polyphenol could ameliorate liver disorders caused by diabetes mellitus in rats. This further validates the use of this species as medicinal herb and spice by the larger population of Nigerians.

  11. The endocannabinoid system and its relevance for nutrition

    DEFF Research Database (Denmark)

    Maccarrone, Mauro; Gasperi, Valeria; Catani, Maria Valeria

    2010-01-01

    Endocannabinoids bind to cannabinoid, vanilloid, and peroxisome proliferator-activated receptors. The biological actions of these polyunsaturated lipids are controlled by key agents responsible for their synthesis, transport and degradation, which together form an endocannabinoid system (ECS......). In the past few years, evidence has been accumulated for a role of the ECS in regulating food intake and energy balance, both centrally and peripherally. In addition, up-regulation of the ECS in the gastrointestinal tract has a potential impact on inflammatory bowel diseases. In this review, the main features...... of the ECS are summarized in order to put in better focus our current knowledge of the nutritional relevance of endocannabinoid signaling and of its role in obesity, cardiovascular pathologies, and gastrointestinal diseases. The central and peripheral pathways that underlie these effects are discussed...

  12. Dual-acting compounds targeting endocannabinoid and endovanilloid systems — a novel treatment option for chronic pain management.

    Directory of Open Access Journals (Sweden)

    Natalia Malek

    2016-08-01

    Full Text Available Compared with acute pain that arises suddenly in response to a specific injury and is usually treatable, chronic pain persists over time and is often resistant to medical treatment. Because of the heterogeneity of chronic pain origins, satisfactory therapies for its treatment are lacking, leading to an urgent need for the development of new treatments. The leading approach in drug design is selective compounds, though they are often less effective and require chronic dosing with many side effects. Herein, we review novel approaches to drug design for the treatment of chronic pain represented by dual-acting compounds, which operate at more than one biological target. A number of studies suggest the involvement of the cannabinoid and vanilloid receptors in pain. Interestingly cannabinoid system is in interrelation with other systems that comprise lipid mediators: prostaglandins, produced by COX enzyme. Therefore, in the present review, we summarize the role of dual-acting molecules (FAAH/TRPV1 and FAAH/COX-2 inhibitors that interact with endocannabinoid and endovanillinoid systems and act as analgesics by elevating the endogenously produced endocannabinoids and dampening the production of pro-inflammatory prostaglandins. The plasticity of the endocannabinoid system and the ability of a single chemical entity to exert an activity on two receptor systems has been developed and extensively investigated. Here, we review up-to-date pharmacological studies on compounds interacting with FAAH enzyme together with TRPV1 receptor or COX-2 enzyme respectively. Multi-target pharmacological intervention for treating pain may lead to the development of original and efficient treatments.

  13. Correlation-based network analysis of metabolite and enzyme profiles reveals a role of citrate biosynthesis in modulating N and C metabolism in Zea mays

    Directory of Open Access Journals (Sweden)

    David Toubiana

    2016-07-01

    Full Text Available To investigate the natural variability of leaf metabolism and enzymatic activity in a maize inbred population, statistical and network analyses were employed on metabolite and enzyme profiles. The test of coefficient of variation showed that sugars and amino acids displayed opposite trends in their variance within the population, consistently with their related enzymes. The overall higher CV values for metabolites as compared to the tested enzymes are indicative for their greater phenotypic plasticity. H2 tests revealed galactinol (1 and asparagine (0.91 as the highest scorers among metabolites and nitrate reductase (0.73, NAD-glutamate dehydrogenase (0.52, and phosphoglucomutase (0.51 among enzymes. The overall low H2 scores for metabolites and enzymes are suggestive for a great environmental impact or gene-environment interaction. Correlation-based network generation followed by community detection analysis, partitioned the network into three main communities and one dyad, (i reflecting the different levels of phenotypic plasticity of the two molecular classes as observed for the CV values and (ii highlighting the concerted changes between classes of chemically related metabolites. Community 1 is composed mainly of enzymes and specialized metabolites, community 2’ is enriched in N-containing compounds and phosphorylated-intermediates. The third community contains mainly organic acids and sugars. Cross-community linkages are supported by aspartate, by the photorespiration amino acids glycine and serine, by the metabolically related GABA and putrescine, and by citrate. The latter displayed the strongest node-betweenness value (185.25 of all nodes highlighting its fundamental structural role in the connectivity of the network by linking between different communities and to the also strongly connected enzyme aldolase.

  14. The multiple functions of the endocannabinoid system: a focus on the regulation of food intake

    Directory of Open Access Journals (Sweden)

    Tibiriça Eduardo

    2010-01-01

    Full Text Available Abstract Background Cannabis sativa (also known as marijuana has been cultivated by man for more than 5,000 years. However, there was a rise in its use in the 20th century for recreational, religious or spiritual, and medicinal purposes. The main psychoactive constituent of cannabis, whose structure was identified in the 1960's, is Δ9-tetrahydrocannabinol. On the other hand, the discovery of cannabinoid receptors and their endogenous agonists took place only very recently. In fact, the first cannabinoid receptor (CB1 was cloned in 1990, followed 3 years later by the characterization of a second cannabinoid receptor (CB2. Since the 19th century, the use of cannabis has been reported to stimulate appetite and increase the consumption of sweet and tasty food, sometimes resulting in significant weight gain. The recent description of the endocannabinoid system, not only in the central nervous system but also in peripheral tissues, points to its involvement in the regulation of appetite, food intake and energy metabolism. Consequently, the pharmacological modulation of the over-activity of this system could be useful in the treatment of the metabolic syndrome. Conclusions The endocannabinoid system has important physiological functions not only in the central nervous system but also in peripheral tissues. The activation of central CB1 receptors, particularly in hypothalamic nuclei and in the limbic system, is involved in the regulation of feeding behavior, and especially in the control of the intake of palatable food. In the periphery, cannabinoid receptors are present in adipocytes, skeletal muscle, gastrointestinal tract and liver, modulating energy metabolism.

  15. Schisandra chinensis regulates drug metabolizing enzymes and drug transporters via activation of Nrf2-mediated signaling pathway

    Directory of Open Access Journals (Sweden)

    He JL

    2014-12-01

    Full Text Available Jin-Lian He,1 Zhi-Wei Zhou,2,3 Juan-Juan Yin,2 Chang-Qiang He,1 Shu-Feng Zhou,2,3 Yang Yu1 1College of Chinese Medicine, Guangzhou University of Chinese Medicine, Guangzhou, Guangdong, People’s Republic of China; 2Department of Pharmaceutical Sciences, College of Pharmacy, University of South Florida, Tampa, FL, USA; 3Guizhou Provincial Key Laboratory for Regenerative Medicine, Stem Cell and Tissue Engineering Research Center and Sino-US Joint Laboratory for Medical Sciences, Guiyang Medical University, Guiyang, Guizhou, People’s Republic of China Abstract: Drug metabolizing enzymes (DMEs and drug transporters are regulated via epigenetic, transcriptional, posttranscriptional, and translational and posttranslational modifications. Phase I and II DMEs and drug transporters play an important role in the disposition and detoxification of a large number of endogenous and exogenous compounds. The nuclear factor (erythroid-derived 2-like 2 (Nrf2 is a critical regulator of a variety of important cytoprotective genes that are involved in disposition and detoxification of xenobiotics. Schisandra chinensis (SC is a commonly used traditional Chinese herbal medicine that has been primarily used to protect the liver because of its potent antioxidative and anti-inflammatory activities. SC can modulate some DMEs and drug transporters, but the underlying mechanisms are unclear. In this study, we aimed to explore the role of Nrf2 in the regulatory effect of SC extract (SCE on selected DMEs and drug transporters in human hepatocellular liver carcinoma cell line (HepG2 cells. The results showed that SCE, schisandrin A, and schisandrin B significantly increased the expression of NAD(PH: Nicotinamide Adenine Dinucleotide Phosphate-oxidase or:quinone oxidoreductase 1, heme oxygenase-1, glutamate–cysteine ligase, and glutathione S-transferase A4 at both transcriptional and posttranscriptional levels. Incubation of HepG2 cells with SCE resulted in a significant

  16. Expression of the vitamin D metabolizing enzyme CYP24A1 at the annulus of human spermatozoa may serve as a novel marker of semen quality

    DEFF Research Database (Denmark)

    Jensen, Martin Blomberg; Jørgensen, A; Nielsen, J E

    2012-01-01

    Vitamin D (VD) is important for male reproduction in mammals and the VD receptor (VDR) and VD-metabolizing enzymes are expressed in human spermatozoa. The VD-inactivating enzyme CYP24A1 titrates the cellular responsiveness to VD, is transcriptionally regulated by VD, and has a distinct expression...... at the sperm annulus. Here, we investigated if CYP24A1 expression serves as a marker for VD metabolism in spermatozoa, and whether CYP24A1 expression was associated with semen quality. We included 130 men (53 healthy young volunteers and 77 subfertile men) for semen analysis and immunocytochemical (ICC.......3%. Functional studies revealed that 1,25(OH)(2) D(3) increased [Ca(2+) ](i) and sperm motility in young healthy men, while 1,25(OH)(2) D(3) was unable to increase motility in subfertile patients. In conclusion, we suggest that CYP24A1 expression at the annulus may serve as a novel marker of semen quality...

  17. Effects of dietary supplementation with green tea waste on growth, digestive enzyme and lipid metabolism of juvenile hybrid tilapia, Oreochromis niloticus × O. aureus.

    Science.gov (United States)

    Zheng, Qingmei; Han, Chunyan; Zhong, Yanmei; Wen, Rushu; Zhong, Ming

    2017-04-01

    An 8-week feeding trial was conducted to evaluate the effects of dietary supplementation with green tea waste (GTW) on growth, digestive enzyme and lipid metabolism of juvenile hybrid tilapia, Oreochromis niloticus × O. aureus. The fish (initial mean body weight, 12.63 ± 0.75 g) were fed five experimental diets that included 0 (control), 0.8, 1.6, 3.2 or 6.4 % of GTW in triplicate aquaria, twice daily. Growth performance, plasma metabolites content and liver and intestine digestive enzyme activities were determined. Fish accepted well all experimental diets during the trial, and no mortality was observed. The weight gain increased (P tilapia to improve growth performance, digestion efficacy and fat metabolism.

  18. Beneficial effects of co-enzyme Q10 and rosiglitazone in fructose-induced metabolic syndrome in rats

    Directory of Open Access Journals (Sweden)

    Suzan M. Mansour

    2013-06-01

    Full Text Available Increased fructose consumption is strongly associated with metabolic syndrome (MS. This study was performed to elucidate the role of co-enzyme Q10 (CoQ and/or rosiglitazone (Rosi in fructose induced MS. Four groups of rats (n = 8–10 were fed on fructose-enriched diet (FED for 16 weeks. One served as FED-control while the remaining groups were treated with CoQ (10 mg/kg/day, Rosi (4 mg/kg/day or their combination during the last 6 weeks. Another group was fed on normal laboratory chow (normal control. At the end of the experiment, blood samples were collected for estimation of markers related to MS. In addition, histological examination of liver, kidney and pancreas samples was done. Induction of the MS was associated with increased body weight gain (34% coupled with elevated levels of blood glucose (48%, insulin (86%, insulin resistance (270%, uric acid (69%, urea (155%, creatinine (129% and blood lipids with different degrees. Fructose-induced MS also reduced plasma catalase (62% and glutathione peroxidase (89% activities parallel to increased serum leptin and tumor necrosis factor-alpha (TNF-α levels. These changes were coupled by marked histological changes in the examined tissues. Treatment with CoQ or Rosi attenuated most of MS-induced changes. Besides, the combination of both agents further reduced blood glucose, total cholesterol, triglycerides and urea levels, as well as, normalized serum levels of leptin and TNF-α. In addition, combined therapy of both agents elevated HDL-cholesterol level and glutathione peroxidase activity. In conclusion, the present study proves the benefits of co-supplementation of CoQ and Rosi in a fructose-induced model of insulin resistance.

  19. Distribution of /sup 3/H-(+-)noradrenaline in rabbit aortic strips after inhibition of the noradrenaline-metabolizing enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Henseling, M; Eckert, E; Trendelenburg, U [Wuerzburg Univ. (Germany, F.R.). Inst. fuer Pharmakologie und Toxikologie

    1976-01-01

    Rabbit aortic strips (nerve-free, reserpine pretreated or normal) whose noradrenaline-metabolizing enzymes were inhibited (by in vitro treatment with 0.5 mM pargyline for 30 min and by the presence of 0.1 mM U-0521) were exposed to 1.18 ..mu..M /sup 3/H-(+-)noradrenaline for 30 min (in most experiments). At the end of the incubation some strips were used for anlysis of radioactivity (i.e., of noradrenaline and its metabolites), while for others the efflux of radioactivity was determined during 240 min of wash out with amine-free solution. An estimate of the original distribution of the amine into the various extraneuronal and neuronal compartments of the tissue was obtained by compartmental analysis of the efflux curves. Extracellular amine distributes into 'compartment I + II' (characterized by a half time for efflux of < 1 min); compartment size and half time for efflux were similar to those obtained for /sup 14/C-sorbitol. The extraneuronal accumulation of noradrenaline is a quickly equilibrating process which involves compartments III and IV (with half times for efflux of 3 and 11 min, respectively). Compartment IV represents not only extraneuronally but also neuronally distributed noradrenaline. The neuronal accumulation of noradrenaline is a slowly equilibrating process which can be subdivided into axoplasmic and vesicular accumulation. The results support the view that the rate of relaxation (of strips initially exposed to noradrenaline and then washed out) is affected by the efflux of unchanged amine form extraneuronal and neuronal stores.

  20. Transcriptional expression analysis of ABC efflux transporters and xenobiotic-metabolizing enzymes in the Chinese rare minnow.

    Science.gov (United States)

    Yuan, Lilai; Lv, Biping; Zha, Jinmiao; Wang, Zijian

    2014-05-01

    In the present study, the cDNA fragments of five ABC transporter genes (ABCB1, ABCB11, ABCC1, ABCC2, and ABCG2) in the rare minnow were cloned, and their tissue-specific expression patterns were evaluated across eight rare minnow tissues (liver, gill, intestine, kidney, spleen, brain, skin, and muscle). Furthermore, the transcriptional effects on these ABC transporter genes and five xenobiotic-metabolizing enzyme genes (CYP1A, GSTm, GSTp1, GCLC, and UGT1a) were determined in the rare minnow liver after 12 days of pyrene exposure. Basal expression analysis showed that the tissues with high expression of the ABC transporters included the liver, kidney, and intestine. Moreover, the most highly expressed of the ABC genes were ABCB1 and ABCC2 in all eight of the tissues tested. The ABCB11 gene was almost exclusively expressed in the liver of the rare minnow, whereas ABCC1 and ABCG2 showed weak expression in all eight tissues compared to ABCB1 and ABCC2. Our results provide the first thorough examination of the expression patterns of toxicologically relevant ABC transporters in the rare minnow and serve as a necessary basis for further studies of these ABC transporters in fish. Furthermore, synergistic up-regulation of CYP1A, GSTp1, GCLC, UGT1a, and ABCC2 was observed in the rare minnow liver following pyrene exposure, while GSTm, ABCB1, ABCB11, ABCC1, and ABCG2 were not significantly affected (p ABC transporters by pyrene suggests a possible involvement and cooperation of these genes in the detoxification process in rare minnows. Copyright © 2014 Elsevier B.V. All rights reserved.

  1. Enzyme Informatics

    Science.gov (United States)

    Alderson, Rosanna G.; Ferrari, Luna De; Mavridis, Lazaros; McDonagh, James L.; Mitchell, John B. O.; Nath, Neetika

    2012-01-01

    Over the last 50 years, sequencing, structural biology and bioinformatics have completely revolutionised biomolecular science, with millions of sequences and tens of thousands of three dimensional structures becoming available. The bioinformatics of enzymes is well served by, mostly free, online databases. BRENDA describes the chemistry, substrate specificity, kinetics, preparation and biological sources of enzymes, while KEGG is valuable for understanding enzymes and metabolic pathways. EzCatDB, SFLD and MACiE are key repositories for data on the chemical mechanisms by which enzymes operate. At the current rate of genome sequencing and manual annotation, human curation will never finish the functional annotation of the ever-expanding list of known enzymes. Hence there is an increasing need for automated annotation, though it is not yet widespread for enzyme data. In contrast, functional ontologies such as the Gene Ontology already profit from automation. Despite our growing understanding of enzyme structure and dynamics, we are only beginning to be able to design novel enzymes. One can now begin to trace the functional evolution of enzymes using phylogenetics. The ability of enzymes to perform secondary functions, albeit relatively inefficiently, gives clues as to how enzyme function evolves. Substrate promiscuity in enzymes is one example of imperfect specificity in protein-ligand interactions. Similarly, most drugs bind to more than one protein target. This may sometimes result in helpful polypharmacology as a drug modulates plural targets, but also often leads to adverse side-effects. Many cheminformatics approaches can be used to model the interactions between druglike molecules and proteins in silico. We can even use quantum chemical techniques like DFT and QM/MM to compute the structural and energetic course of enzyme catalysed chemical reaction mechanisms, including a full description of bond making and breaking. PMID:23116471

  2. Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

    International Nuclear Information System (INIS)

    Chen, Qi-Liang; Luo, Zhi; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

    2013-01-01

    Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

  3. Differential induction of enzymes and genes involved in lipid metabolism in liver and visceral adipose tissue of juvenile yellow catfish Pelteobagrus fulvidraco exposed to copper

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Qi-Liang; Luo, Zhi, E-mail: luozhi99@yahoo.com.cn; Pan, Ya-Xiong; Zheng, Jia-Lang; Zhu, Qing-Ling; Sun, Lin-Dan; Zhuo, Mei-Qin; Hu, Wei

    2013-07-15

    Highlights: •Cu downregulates lipogenesis and reduces lipid deposition in liver and adipose tissue. •Mechanism of Cu affecting lipid metabolism is determined at the enzymatic and molecular levels. •Cu exposure differentially influences lipid metabolism between liver and adipose tissue. -- Abstract: The present study was conducted to determine the mechanism of waterborne Cu exposure influencing lipid metabolism in liver and visceral adipose tissue (VAT) of juvenile yellow catfish Pelteobagrus fulvidraco. Yellow catfish were exposed to four waterborne copper (Cu) concentrations (2 (control), 24 (low), 71 (medium), 198 (high) μg Cu/l, respectively) for 6 weeks. Waterborne Cu exposure had a negative effect on growth and several condition indices (condition factor, viscerosomatic index, hepatosomatic index and visceral adipose index). In liver, lipid content, activities of lipogenic enzymes (6-phosphogluconate dehydrogenase (6PGD), glucose-6-phosphate dehydrogenase (G6PD), malic enzyme (ME), isocitrate dehydrogenase (ICDH), and fatty acid synthase (FAS)) as well as mRNA levels of 6PGD, G6PD, FAS and sterol-regulator element-binding protein-1 (SREBP-1) genes decreased with increasing Cu concentrations. However, activity and mRNA level of lipoprotein lipase (LPL) gene in liver increased. In VAT, G6PD, ME and LPL activities as well as the mRNA levels of FAS, LPL and PPARγ genes decreased in fish exposed to higher Cu concentrations. The differential Pearson correlations between transcription factors (SREBP-1 and peroxisome proliferators-activated receptor-γ (PPARγ)), and the activities and mRNA expression of lipogenic enzymes and their genes were observed between liver and VAT. Thus, our study indicated that reduced lipid contents in liver and VAT after Cu exposure were attributable to the reduced activities and mRNA expression of lipogenic enzymes and their genes in these tissues. Different response patterns of several tested enzymes and genes to waterborne Cu

  4. 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

  5. Gene polymorphisms of desaturase enzymes of polyunsaturated fatty acid metabolism and adiponutrin and the increased risk of nonalcoholic fatty liver disease

    OpenAIRE

    Manvi Vernekar; Deepak Amarapurkar; Kalpana Joshi; Rekha Singhal

    2017-01-01

    Nonalcoholic fatty liver disease (NAFLD) is considered to be the hepatic manifestation of the metabolic syndrome (MetS). Adiponutrin gene polymorphisms have been associated with NAFLD worldwide. Polyunsaturated fatty acids (PUFAs) have been studied to have anti-inflammatory effects and plasma lipid lowering properties. PUFAs are endogenously synthesized with the help of delta-6-desaturase and delta-5-desaturase enzymes. They are encoded by FADS2 and FADS1 genes respectively. Polymorphisms in ...

  6. Ethnic differences in the prevalence of polymorphisms in CYP7A1, CYP7B1 AND CYP27A1 enzymes involved in cholesterol metabolism

    OpenAIRE

    Dias, Vera; Ribeiro, V.

    2011-01-01

    It is well known that drug disposition and response are greatly determined by the activities of drug metabolizing enzymes, which are polymorphic. Some of these polymorphisms are clinically relevant and presented an ethnic-dependent pattern of distribution. The characterization of the genetic distribution of different populations allows the selection of therapeutic options in accordance with the genetic background, with the objective to avoid adverse reactions and inefficacy of the treatment. ...

  7. Independent and supra-additive effects of alcohol consumption, cigarette smoking, and metabolic syndrome on the elevation of serum liver enzyme levels.

    Directory of Open Access Journals (Sweden)

    Eun Young Park

    Full Text Available We investigated the independent and combined effects of alcohol consumption, cigarette smoking and metabolic syndrome on abnormal liver function, i.e., the elevation of serum liver enzyme levels. Participants of a Korean population-based prospective cohort aged ≥30 years without liver disease, diabetes, or cardiovascular diseases were included. Information on alcohol consumption, smoking status, and metabolic syndrome, defined as per the criteria of the Adult Treatment Panel III, were applied to evaluate their impact on serum levels of aspartate aminotransferase (AST, alanine aminotransferase (ALT, and gamma-glutamyl transferase (GGT. Alcohol consumption, cigarette smoking and metabolic syndrome were the significant individual factors that elevated serum liver enzyme levels. Supra-additive effects of metabolic syndrome and either alcohol consumption or cigarette smoking were also identified. The combination of heavy drinking (≥24 g/day and metabolic syndrome conferred an effect that was higher than the sum of the two individual effects (Synergic Index (SI: AST, 2.37 [1.20-4.67]; GGT, 1.91 [1.17-3.13]. Only GGT level (odds ratio 6.04 [3.68-9.94], SI 2.33 [1.24-4.41] was significantly elevated when the effect of moderate drinking (20 pack years, 1.80 for ≥24 g/day and ≤20 pack years, 2.03 for ≥24 g/day and >20 pack years, while only the combined effect of drinking ≥24 g/day and smoking >20 pack years elevated the AST level (SI 4.55 [3.12-6.61]. The combined effect of cigarette smoking and metabolic syndrome was not supra-additive. To prevent fatty liver disease and other related diseases, a multifactorial prevention strategy that includes limited alcohol consumption, smoking cessation and rectification of adverse metabolic profiles is required.

  8. Differential Regulation of Eicosanoid and Endocannabinoid Production by Inflammatory Mediators in Human Choriodecidua.

    Directory of Open Access Journals (Sweden)

    M D Mitchell

    Full Text Available An increase in intrauterine prostaglandin production is critical for the onset and progression of labor in women and indeed all mammalian species studied. Endocannabinoids can act as substrates for enzymes of the prostaglandin biosynthetic pathways and can be utilized to generate other related compounds such as prostamides. The end products are indistinguishable by radioimmunoassay. We have separated such compounds by mass spectrometry. We now show that inflammatory stimuli such as LPS and proinflammatory cytokines act differentially on these pathways in human choriodecidua and preferentially create drive through to prostaglandin end products. These findings create doubt about the interpretation of data on prostaglandin biosynthesis in intrauterine tissues from pregnant women especially in the presence of an infection. The possibility is raised that separation of these products might reduce variability in results and lead to potential uses for their measurement in the diagnosis of preterm labor.

  9. 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.)

  10. Evaluation of the synergistic effect of Allium sativum, Eugenia jambolana, Momordica charantia, Ocimum sanctum and Psidium guajav on hepatic and intestinal drug metabolizing enzymes in rats

    Directory of Open Access Journals (Sweden)

    Devendra Kumar

    2016-12-01

    Full Text Available Aims/Background: Present study investigated the synergistic effect of polyherbal formulations (PHF of Allium sativum L Eugenia jambolana Lam., Momordica charantia L., Ocimum sanctum Linn and Psidium guajava L. in the inhibition/induction of hepatic and intestinal CYPs and Phase-II conjugated drug metabolizing enzymes. Consumption of these herbal remedy has been extensively documented for diabetes treatment in Auyureda. Methodology: PHF of these five herbs was prepared and different doses were orally administered to Sprague Dawley rats of different groups except control group. Expression of mRNA and activity of drug metabolizing enzymes were examined by RT-PCR and HPLC in isolated liver and intestine microsomes in PHF pretreated rats. Results: Activities of hepatic and intestinal Phase-II enzyme levels increased along with mRNA levels except CYP3A mRNA level. PHF administration increases the activity of hepatic and intestinal UDPGT and GST in response to dose and time; however, activity of hepatic SULT increased at higher doses. Conclusions: CYPs and Phase-II conjugated enzymes levels can be modulated in dose and time dependent manner. Observations suggest that poly herbal formulation might be a possible cause of herb-drug interaction, due to changes in pharmacokinetic of crucial CYPs and Phase-II substrate drug. [J Complement Med Res 2016; 5(4.000: 372-382

  11. Metabolism

    Science.gov (United States)

    ... Are More Common in People With Type 1 Diabetes Metabolic Syndrome Your Child's Weight Healthy Eating Endocrine System Blood Test: Basic Metabolic Panel (BMP) Activity: Endocrine System Growth Disorders Diabetes Center Thyroid Disorders Your Endocrine System Movie: Endocrine ...

  12. The endocannabinoid gene faah2a modulates stress-associated behavior in zebrafish.

    Directory of Open Access Journals (Sweden)

    Randall G Krug

    Full Text Available The ability to orchestrate appropriate physiological and behavioral responses to stress is important for survival, and is often dysfunctional in neuropsychiatric disorders that account for leading causes of global disability burden. Numerous studies have shown that the endocannabinoid neurotransmitter system is able to regulate stress responses and could serve as a therapeutic target for the management of these disorders. We used quantitative reverse transcriptase-polymerase chain reactions to show that genes encoding enzymes that synthesize (abhd4, gde1, napepld, enzymes that degrade (faah, faah2a, faah2b, and receptors that bind (cnr1, cnr2, gpr55-like endocannabinoids are expressed in zebrafish (Danio rerio. These genes are conserved in many other vertebrates, including humans, but fatty acid amide hydrolase 2 has been lost in mice and rats. We engineered transcription activator-like effector nucleases to create zebrafish with mutations in cnr1 and faah2a to test the role of these genes in modulating stress-associated behavior. We showed that disruption of cnr1 potentiated locomotor responses to hyperosmotic stress. The increased response to stress was consistent with rodent literature and served to validate the use of zebrafish in this field. Moreover, we showed for the first time that disruption of faah2a attenuated the locomotor responses to hyperosmotic stress. This later finding suggests that FAAH2 may be an important mediator of stress responses in non-rodent vertebrates. Accordingly, FAAH and FAAH2 modulators could provide distinct therapeutic options for stress-aggravated disorders.

  13. Antioxidant status and endocannabinoid concentration in postpartum depressive women

    Directory of Open Access Journals (Sweden)

    Mina Ranjbaran

    2015-02-01

    Conclusion: Women’s Job, husband’s job, wanted or unwanted pregnancy from husbands and marital period are associated to postpartum depression. In postpartum depression, TAC, AEA and 2-AG are reduced. So it can be concluded that both antioxidant system and endocannabinoid concentration involved in the development of postpartum depression.

  14. An endocannabinoid hypothesis of drug reward and drug addiction.

    Science.gov (United States)

    Onaivi, Emmanuel S

    2008-10-01

    Pharmacologic treatment of drug and alcohol dependency has largely been disappointing, and new therapeutic targets and hypotheses are needed. There is accumulating evidence indicating a central role for the previously unknown but ubiquitous endocannabinoid physiological control system (EPCS) in the regulation of the rewarding effects of abused substances. Thus an endocannabinoid hypothesis of drug reward is postulated. Endocannabinoids mediate retrograde signaling in neuronal tissues and are involved in the regulation of synaptic transmission to suppress neurotransmitter release by the presynaptic cannabinoid receptors (CB-Rs). This powerful modulatory action on synaptic transmission has significant functional implications and interactions with the effects of abused substances. Our data, along with those from other investigators, provide strong new evidence for a role for EPCS modulation in the effects of drugs of abuse, and specifically for involvement of cannabinoid receptors in the neural basis of addiction. Cannabinoids and endocannabinoids appear to be involved in adding to the rewarding effects of addictive substances, including, nicotine, opiates, alcohol, cocaine, and BDZs. The results suggest that the EPCS may be an important natural regulatory mechanism for drug reward and a target for the treatment of addictive disorders.

  15. The endocannabinoid system and appetite: relevance for food reward

    NARCIS (Netherlands)

    Jager, G.; Witkamp, R.F.

    2014-01-01

    Mounting evidence substantiates the central role of the endocannabinoid system (ECS) in the modulation of both homeostatic and hedonic elements of appetite and food intake. Conversely, feeding status and dietary patterns directly influence activity of the ECS. Following a general introduction on the

  16. Polymorphisms in the endocannabinoid receptor 1 in relation to fat mass distribution

    DEFF Research Database (Denmark)

    Nielsen, Morten Frost; Nielsen, T L; Wraae, K

    2010-01-01

    OBJECTIVE: Both animal and human studies have associated the endocannabinoid system with obesity and markers of metabolic dysfunction. Blockade of the cannabinoid receptor 1 (CB1) caused weight loss and reduction in waist size in both obese and type II diabetics. Recent studies on common variants...... of the CB1 receptor gene (CNR1) and the link to obesity have been conflicting. The aim of the present study was to evaluate whether selected common variants of the CNR1 are associated with measures of obesity and fat distribution. DESIGN AND METHODS: The single nucleotide polymorphisms (SNPs) rs806381, rs......10485179 and rs1049353 were genotyped, and body fat and fat distribution were assessed by the use of dual-energy X-ray absorptiometry and magnetic resonance imaging in a population-based study comprising of 783 Danish men, aged 20-29 years. RESULTS: The rs806381 polymorphism was significantly associated...

  17. Expression of S1P metabolizing enzymes and receptors correlate with survival time and regulate cell migration in glioblastoma multiforme.

    Science.gov (United States)

    Bien-Möller, Sandra; Lange, Sandra; Holm, Tobias; Böhm, Andreas; Paland, Heiko; Küpper, Johannes; Herzog, Susann; Weitmann, Kerstin; Havemann, Christoph; Vogelgesang, Silke; Marx, Sascha; Hoffmann, Wolfgang; Schroeder, Henry W S; Rauch, Bernhard H

    2016-03-15

    A signaling molecule which is involved in proliferation and migration of malignant cells is the lipid mediator sphingosine-1-phosphate (S1P). There are hints for a potential role of S1P signaling in malignant brain tumors such as glioblastoma multiforme (GBM) which is characterized by a poor prognosis. Therefore, a comprehensive expression analysis of S1P receptors (S1P1-S1P5) and S1P metabolizing enzymes in human GBM (n = 117) compared to healthy brain (n = 10) was performed to evaluate their role for patient´s survival. Furthermore, influence of S1P receptor inhibition on proliferation and migration were studied in LN18 GBM cells. Compared to control brain, mRNA levels of S1P1, S1P2, S1P3 and S1P generating sphingosine kinase-1 were elevated in GBM. Kaplan-Meier analyses demonstrated an association between S1P1 and S1P2 with patient´s survival times. In vitro, an inhibitory effect of the SphK inhibitor SKI-II on viability of LN18 cells was shown. S1P itself had no effect on viability but stimulated LN18 migration which was blocked by inhibition of S1P1 and S1P2. The participation of S1P1 and S1P2 in LN18 migration was further supported by siRNA-mediated silencing of these receptors. Immunoblots and inhibition experiments suggest an involvement of the PI3-kinase/AKT1 pathway in the chemotactic effect of S1P in LN18 cells.In summary, our data argue for a role of S1P signaling in proliferation and migration of GBM cells. Individual components of the S1P pathway represent prognostic factors for patients with GBM. Perspectively, a selective modulation of S1P receptor subtypes could represent a therapeutic approach for GBM patients and requires further evaluation.

  18. Enzymatic synthesis of RNAs capped with nucleotide analogues reveals the molecular basis for substrate selectivity of RNA capping enzyme: impacts on RNA metabolism.

    Directory of Open Access Journals (Sweden)

    Moheshwarnath Issur

    Full Text Available RNA cap binding proteins have evolved to specifically bind to the N7-methyl guanosine cap structure found at the 5' ends of eukaryotic mRNAs. The specificity of RNA capping enzymes towards GTP for the synthesis of this structure is therefore crucial for mRNA metabolism. The fact that ribavirin triphosphate was described as a substrate of a viral RNA capping enzyme, raised the possibility that RNAs capped with nucleotide analogues could be generated in cellulo. Owing to the fact that this prospect potentially has wide pharmacological implications, we decided to investigate whether the active site of the model Paramecium bursaria Chlorella virus-1 RNA capping enzyme was flexible enough to accommodate various purine analogues. Using this approach, we identified several key structural determinants at each step of the RNA capping reaction and generated RNAs harboring various different cap analogues. Moreover, we monitored the binding affinity of these novel capped RNAs to the eIF4E protein and evaluated their translational properties in cellulo. Overall, this study establishes a molecular rationale for the specific selection of GTP over other NTPs by RNA capping enzyme It also demonstrates that RNAs can be enzymatically capped with certain purine nucleotide analogs, and it also describes the impacts of modified RNA caps on specific steps involved in mRNA metabolism. For instance, our results indicate that the N7-methyl group of the classical N7-methyl guanosine cap is not always indispensable for binding to eIF4E and subsequently for translation when compensatory modifications are present on the capped residue. Overall, these findings have important implications for our understanding of the molecular determinants involved in both RNA capping and RNA metabolism.

  19. Silymarin protects PBMC against B(a)P induced toxicity by replenishing redox status and modulating glutathione metabolizing enzymes-An in vitro study

    International Nuclear Information System (INIS)

    Kiruthiga, P.V.; Pandian, S. Karutha; Devi, K. Pandima

    2010-01-01

    PAHs are a ubiquitous class of environmental contaminants that have a large number of hazardous consequences on human health. An important prototype of PAHs, B(a)P, is notable for being the first chemical carcinogen to be discovered and the one classified by EPA as a probable human carcinogen. It undergoes metabolic activation to QD, which generate ROS by redox cycling system in the body and oxidatively damage the macromolecules. Hence, a variety of antioxidants have been tested as possible protectors against B(a)P toxicity. Silymarin is one such compound, which has high human acceptance, used clinically and consumed as dietary supplement around the world for its strong anti-oxidant efficacy. Silymarin was employed as an alternative approach for treating B(a)P induced damage and oxidative stress in PBMC, with an emphasis to provide the molecular basis for the effect of silymarin against B(a)P induced toxicity. PBMC cells exposed to either benzopyrene (1 μM) or silymarin (2.4 mg/ml) or both was monitored for toxicity by assessing LPO, PO, redox status (GSH/GSSG ratio), glutathione metabolizing enzymes GR and GPx and antioxidant enzymes CAT and SOD. This study also investigated the protective effect of silymarin against B(a)P induced biochemical alteration at the molecular level by FT-IR spectroscopy. Our findings were quite striking that silymarin possesses substantial protective effect against B(a)P induced oxidative stress and biochemical changes by restoring redox status, modulating glutathione metabolizing enzymes, hindering the formation of protein oxidation products, inhibiting LPO and further reducing ROS mediated damages by changing the level of antioxidant enzymes. The results suggest that silymarin exhibits multiple protections and it should be considered as a potential protective agent for environmental contaminant induced immunotoxicity.

  20. Identification of enzymes and quantification of metabolic fluxes in the wild type and in a recombinant Aspergillus oryzae strain

    DEFF Research Database (Denmark)

    Pedersen, Henrik; Carlsen, Morten; Nielsen, Jens Bredal

    1999-01-01

    Two alpha-amylase-producing strains of Aspergillus oryzae, a wild-type strain and a recombinant containing additional copies of the alpha-amylase gene, were characterized,vith respect to enzyme activities, localization of enzymes to the mitochondria or cytosol, macromolecular composition...

  1. Protective effect of bioflavonoid myricetin enhances carbohydrate metabolic enzymes and insulin signaling molecules in streptozotocin–cadmium induced diabetic nephrotoxic rats

    International Nuclear Information System (INIS)

    Kandasamy, Neelamegam; Ashokkumar, Natarajan

    2014-01-01

    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. - Highlights: • Diabetic rats are more susceptible to cadmium nephrotoxicity. • Cadmium plays as a cumulative

  2. Protective effect of bioflavonoid myricetin enhances carbohydrate metabolic enzymes and insulin signaling molecules in streptozotocin–cadmium induced diabetic nephrotoxic rats

    Energy Technology Data Exchange (ETDEWEB)

    Kandasamy, Neelamegam; Ashokkumar, Natarajan, E-mail: npashokkumar1@gmail.com

    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. - Highlights: • Diabetic rats are more susceptible to cadmium nephrotoxicity. • Cadmium plays as a cumulative

  3. 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.

  4. Dissecting the insect metabolic machinery using twin ion mass spectrometry: a single P450 enzyme metabolizing the insecticide imidacloprid in vivo.

    Science.gov (United States)

    Hoi, Kin Kuan; Daborn, Phillip J; Battlay, Paul; Robin, Charles; Batterham, Philip; O'Hair, Richard A J; Donald, William A

    2014-04-01

    Insecticide resistance is one of the most prevalent examples of anthropogenic genetic change, yet our understanding of metabolic-based resistance remains limited by the analytical challenges associated with rapidly tracking the in vivo metabolites of insecticides at nonlethal doses. Here, using twin ion mass spectrometry analysis of the extracts of whole Drosophila larvae and excreta, we show that (i) eight metabolites of the neonicotinoid insecticide, imidacloprid, can be detected when formed by susceptible larval genotypes and (ii) the specific overtranscription of a single gene product, Cyp6g1, associated with the metabolic resistance to neonicotinoids, results in a significant increase in the formation of three imidacloprid metabolites that are formed in C-H bond activation reactions; that is, Cyp6g1 is directly linked to the enhanced metabolism of imidacloprid in vivo. These results establish a rapid and sensitive method for dissecting the metabolic machinery of insects by directly linking single gene products to insecticide metabolism.

  5. Relationship between intratumoral expression of genes coding for xenobiotic-metabolizing enzymes and benefit from adjuvant tamoxifen in estrogen receptor alpha-positive postmenopausal breast carcinoma

    International Nuclear Information System (INIS)

    Bièche, Ivan; Girault, Igor; Urbain, Estelle; Tozlu, Sengül; Lidereau, Rosette

    2004-01-01

    Little is known of the function and clinical significance of intratumoral dysregulation of xenobiotic-metabolizing enzyme expression in breast cancer. One molecular mechanism proposed to explain tamoxifen resistance is altered tamoxifen metabolism and bioavailability. To test this hypothesis, we used real-time quantitative RT-PCR to quantify the mRNA expression of a large panel of genes coding for the major xenobiotic-metabolizing enzymes (12 phase I enzymes, 12 phase II enzymes and three members of the ABC transporter family) in a small series of normal breast (and liver) tissues, and in estrogen receptor alpha (ERα)-negative and ERα-positive breast tumors. Relevant genes were further investigated in a well-defined cohort of 97 ERα-positive postmenopausal breast cancer patients treated with primary surgery followed by adjuvant tamoxifen alone. Seven of the 27 genes showed very weak or undetectable expression in both normal and tumoral breast tissues. Among the 20 remaining genes, seven genes (CYP2A6, CYP2B6, FMO5, NAT1, SULT2B1, GSTM3 and ABCC11) showed significantly higher mRNA levels in ERα-positive breast tumors than in normal breast tissue, or showed higher mRNA levels in ERα-positive breast tumors than in ERα-negative breast tumors. In the 97 ERα-positive breast tumor series, most alterations of these seven genes corresponded to upregulations as compared with normal breast tissue, with an incidence ranging from 25% (CYP2A6) to 79% (NAT1). Downregulation was rare. CYP2A6, CYP2B6, FMO5 and NAT1 emerged as new putative ERα-responsive genes in human breast cancer. Relapse-free survival was longer among patients with FMO5-overexpressing tumors or NAT1-overexpressing tumors (P = 0.0066 and P = 0.000052, respectively), but only NAT1 status retained prognostic significance in Cox multivariate regression analysis (P = 0.0013). Taken together, these data point to a role of genes coding for xenobiotic-metabolizing enzymes in breast tumorigenesis, NAT1 being an

  6. Metabolic rates, enzyme activities and chemical compositions of some deep-sea pelagic worms, particularly Nectonemertes mirabilis (Nemertea; Hoplonemertinea) and Poeobius meseres (Annelida; Polychaeta)

    Science.gov (United States)

    Thuesen, Erik V.; Childress, James J.

    1993-05-01

    Investigations of metabolic rate, enzyme activity and chemical composition were undertaken on two abundant deep-sea pelagic worms: Nectonemertes mirabilis (Nemertea; Hoplonemertinea) and Poeobius meseres (Annelida; Polychaeta). Six other species of worms ( Pelagonemertes brinkmanni (Nemertea) and the following polychaetes: Pelagobia species A, Tomopteris nisseni, Tomopteris pacifica, Tomopteris species A, and Traviopsis lobifera) were captured in smaller numbers and used for comparison in the physiological and biochemical measurements. Polychaete worms had the highest oxygen consumption rates and, along with N. mirabilis, displayed significant size effects on metabolic rate. Poeobius meseres had the lowest rates of oxygen consumption and displayed no significant relationship of oxygen consumption rate to wet weight. No significant effect of size on the activities of citrate synthase, lactate dehydrogenase or pyruvate kinase was observed in P. meseres or N. mirabilis. Lipid content was higher than protein content for all the worms in this study. Carbohydrate was of little significance in these worms and was usually metabolic rates. It appears that polychaete worms as a group have higher metabolic rates than bathypelagic shrimps, copepods and fishes, and may be the animals with the highest metabolic rates in the bathypelagic regions of the world's oceans.

  7. Type 2 Diabetic Rats on Diet Supplemented With Chromium Malate Show Improved Glycometabolism, Glycometabolism-Related Enzyme Levels and Lipid Metabolism

    Science.gov (United States)

    Feng, Weiwei; Zhao, Ting; Mao, Guanghua; Wang, Wei; Feng, Yun; Li, Fang; Zheng, Daheng; Wu, Huiyu; Jin, Dun; Yang, Liuqing; Wu, Xiangyang

    2015-01-01

    Our previous study showed that chromium malate improved the regulation of blood glucose in mice with alloxan-induced diabetes. The present study was designed to evaluate the effect of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism in type 2 diabetic rats. Our results showed that fasting blood glucose, serum insulin level, insulin resistance index and C-peptide level in the high dose group had a significant downward trend when compared with the model group, chromium picolinate group and chromium trichloride group. The hepatic glycogen, glucose-6-phosphate dehydrogenase, glucokinase, Glut4, phosphor-AMPKβ1 and Akt levels in the high dose group were significantly higher than those of the model, chromium picolinate and chromium trichloride groups. Chromium malate in a high dose group can significantly increase high density lipoprotein cholesterol level while decreasing the total cholesterol, low density lipoprotein cholesterol and triglyceride levels when compared with chromium picolinate and chromium trichloride. The serum chromium content in chromium malate and chromium picolinate group is significantly higher than that of the chromium trichloride group. The results indicated that the curative effects of chromium malate on glycometabolism, glycometabolism-related enzymes and lipid metabolism changes are better than those of chromium picolinate and chromium trichloride. Chromium malate contributes to glucose uptake and transport in order to improved glycometabolism and glycometabolism-related enzymes. PMID:25942313

  8. Influence of gamma radiation on the activities of some carbohydrate metabolic enzymes in the cotyledons and the leaves of fenugreek (Trigonella foenum-graecum L.) bean seedlings

    International Nuclear Information System (INIS)

    Ahanotu, P.A.

    1985-01-01

    Studies indicated that 21-day old cotyledons from gamma irradiated seeds of fenugreek beans were heavier and had more starch and sugar than their non-irradiated controls. To test whether these effects occurred in the leaves and to seek a possible biochemical explanation for these results, the activities of five enzymes involved in carbohydrate metabolism were studied. Three groups of fenugreek bean seeds were irradiated (100-300 Gy) and then allowed to grow for 21 days. On harvest, wet and dry weights of both cotyledons and leaves were determined. Starch and sugar contents in cotyledons and leaves were measured. The five enzymes α-amylase, β-amylase, starch phosphorylase, ADPG-pyrophosphorylase and ribulose-1,5-diphosphate carboxylase were extracted from cotyledons and leaves, respectively. The protein contents and activities of the enzyme extracts were determined. The results suggest an increase in carbohydrate metabolism in cotyldeons and a decrease in leaves due to the radiation treatment of the seeds before germination. Thus, increased amounts of starch and sugars are observed in the cotyledons, and decreased amounts in the leaves. Radiation damage to the translocatory system of the plant may retard the movement of sugars from the cotyledons to the other parts of the plant. This may cause accumulation of sugars and starch in the cotyledons, leading to an increase in their size and weight

  9. Pan-pathway based interaction profiling of FDA-approved nucleoside and nucleobase analogs with enzymes of the human nucleotide metabolism.

    Science.gov (United States)

    Egeblad, Louise; Welin, Martin; Flodin, Susanne; Gräslund, Susanne; Wang, Liya; Balzarini, Jan; Eriksson, Staffan; Nordlund, Pär

    2012-01-01

    To identify interactions a nucleoside analog library (NAL) consisting of 45 FDA-approved nucleoside analogs was screened against 23 enzymes of the human nucleotide metabolism using a thermal shift assay. The method was validated with deoxycytidine kinase; eight interactions known from the literature were detected and five additional interactions were revealed after the addition of ATP, the second substrate. The NAL screening gave relatively few significant hits, supporting a low rate of "off target effects." However, unexpected ligands were identified for two catabolic enzymes guanine deaminase (GDA) and uridine phosphorylase 1 (UPP1). An acyclic guanosine prodrug analog, valaciclovir, was shown to stabilize GDA to the same degree as the natural substrate, guanine, with a ΔT(agg) around 7°C. Aciclovir, penciclovir, ganciclovir, thioguanine and mercaptopurine were also identified as ligands for GDA. The crystal structure of GDA with valaciclovir bound in the active site was determined, revealing the binding of the long unbranched chain of valaciclovir in the active site of the enzyme. Several ligands were identified for UPP1: vidarabine, an antiviral nucleoside analog, as well as trifluridine, idoxuridine, floxuridine, zidovudine, telbivudine, fluorouracil and thioguanine caused concentration-dependent stabilization of UPP1. A kinetic study of UPP1 with vidarabine revealed that vidarabine was a mixed-type competitive inhibitor with the natural substrate uridine. The unexpected ligands identified for UPP1 and GDA imply further metabolic</