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Publication
Journal: Journal of the American Chemical Society
August/7/2007
Abstract
Geosmin is responsible for the characteristic odor of moist soil. Incubation of recombinant germacradienol synthase, encoded by the SCO6073 (SC9B1.20) gene of the Gram-positive soil bacterium Streptomyces coelicolor, with farnesyl diphosphate (2, FPP) in the presence of Mg2+ gave a mixture of (4S,7R)-germacra-1(10)E,5E-diene-11-ol (3) (74%), (-)-(7S)-germacrene D (4) (10%), geosmin (1) (13%), and a hydrocarbon, tentatively assigned the structure of octalin 5 (3%). Individual incubations of recombinant germacradienol synthase with [1,1-2H2]FPP (2a), (1R)-[1-2H]-FPP (2b), and (1S)-[1-2H]-FPP (2c), as well as with FPP (2) in D2O, and GC-MS analysis of the resulting deuterated products supported a mechanism of geosmin formation involving proton-initiated cyclization and retro-Prins fragmentation of the initially formed germacradienol to give intermediate 5, followed by protonation of 5, 1,2-hydride shift, and capture of water.
Publication
Journal: Science Translational Medicine
May/21/2013
Abstract
Angelman syndrome is a neurodevelopmental disorder caused by loss of function of the UBE3A gene encoding a ubiquitin E3 ligase. Motor dysfunction is a characteristic feature of Angelman syndrome, but neither the mechanisms of action nor effective therapeutic strategies have yet been elucidated. We report that tonic inhibition is specifically decreased in cerebellar granule cells of Ube3a-deficient mice, a model of Angelman syndrome. As a mechanism underlying this decrease in tonic inhibition, we show that Ube3a controls degradation of γ-aminobutyric acid (GABA) transporter 1 (GAT1) and that deficiency of Ube3a induces a surplus of GAT1 that results in a decrease in GABA concentrations in the extrasynaptic space. Administering low doses of 4,5,6,7-tetrahydroisothiazolo-[5,4-c]pyridin-3-ol (THIP), a selective extrasynaptic GABA(A) receptor agonist, improves the abnormal firing properties of a population of Purkinje cells in cerebellar brain slices and reduces cerebellar ataxia in Ube3a-deficient mice in vivo. These results suggest that pharmacologically increasing tonic inhibition may be a useful strategy for alleviating motor dysfunction in Angelman syndrome.
Publication
Journal: Environmental Health Perspectives
March/8/2006
Abstract
We investigated estrogen-like properties of five perfluorinated compounds using a combination of three in vitro assays. By means of an E-screen assay, we detected the proliferation-promoting capacity of the fluorotelomer alcohols 1H,1H,2H,2H-perfluorooctan-1-ol (6:2 FTOH) and 1H,1H,2H,2H-perfluoro-decan-1-ol (8:2 FTOH). The more widely environmentally distributed compounds perfluoro-1-octane sulfonate, perfluorooctanoic acid, and perfluorononanoic acid did not seem to possess this hormone-dependent proliferation capacity. We investigated cell cycle dynamics using flow cytometric analyses of the DNA content of the nuclei of MCF-7 breast cancer cells. Exposure to both fluorotelomer alcohols stimulated resting MCF-7 cells to reenter the synthesis phase (S-phase) of the cell cycle. After only 24 hr of treatment, we observed significant increases in the percentage of cells in the S-phase. In order to further investigate the resemblance of the newly detected xenoestrogens to the reference compound 17beta-estradiol (E2), gene expression of a number of estrogen-responsive genes was analyzed by real-time polymerase chain reaction. With E2, as well as 4-nonylphenol and the fluorotelomer alcohols, we observed up-regulation of trefoil factor 1, progesterone receptor, and PDZK1 and down-regulation of ERBB2 gene expression. We observed small but relevant up-regulation of the estrogen receptor as a consequence of exposures to 6:2 FTOH or 8:2 FTOH. The latter finding suggests an alternative mode of action of the fluorotelomer alcohols compared with that of E2. This study clearly underlines the need for future in vivo testing for specific endocrine-related end points.
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Publication
Journal: Journal of Neuroscience
March/31/2011
Abstract
The decision to perform, or not perform, actions known to lead to a rewarding outcome is strongly influenced by the current incentive value of the reward. Incentive value is largely determined by the affective experience derived during previous consumption of the reward-the process of incentive learning. We trained rats on a two-lever, seeking-taking chain paradigm for sucrose reward, in which responding on the initial seeking lever of the chain was demonstrably controlled by the incentive value of the reward. We found that infusion of the μ-opioid receptor antagonist, CTOP (d-Phe-Cys-Tyr-d-Trp-Orn-Thr-Pen-Thr-NH(2)), into the basolateral amygdala (BLA) during posttraining, noncontingent consumption of sucrose in a novel elevated-hunger state (a positive incentive learning opportunity) blocked the encoding of incentive value information normally used to increase subsequent sucrose-seeking responses. Similar treatment with δ [N, N-diallyl-Tyr-Aib-Aib-Phe-Leu-OH (ICI 174,864)] or κ [5'-guanidinonaltrindole (GNTI)] antagonists was without effect. Interestingly, none of these drugs affected the ability of the rats to encode a decrease in incentive value resulting from experiencing the sucrose in a novel reduced-hunger state. However, the μ agonist, DAMGO ([d-Ala2, NMe-Phe4, Gly5-ol]-enkephalin), appeared to attenuate this negative incentive learning. These data suggest that upshifts and downshifts in endogenous opioid transmission in the BLA mediate the encoding of positive and negative shifts in incentive value, respectively, through actions at μ-opioid receptors, and provide insight into a mechanism through which opiates may elicit inappropriate desire resulting in their continued intake in the face of diminishing affective experience.
Publication
Journal: Cancer Epidemiology Biomarkers and Prevention
June/28/2007
Abstract
Intake of flavonoids has been inversely related to the risk of various common neoplasms, but limited data exist on renal cell carcinoma (RCC). We used data from a case-control study conducted between 1994 and 2002 in four Italian areas to study the relation between major flavonoid classes and RCC. The study included 767 cases with incident, histologically confirmed RCC and 1,534 hospital controls admitted for acute, nonneoplastic conditions and matched with cases by study center, sex, and quinquennia of age. We applied published data on food and beverage content of six major classes of flavonoids to dietary information collected through a validated food frequency questionnaire. After adjustment for major recognized confounding factors and total energy intake, the odds ratios for subjects in the highest versus the lowest quintile of intake were 0.80 [95% confidence interval (95% CI), 0.58-1.11] for total flavonoids, 0.76 (95% CI, 0.56-1.03) for isoflavones, 0.94 (95% CI, 0.60-1.47) for anthocyanidins, 0.77 (95% CI, 0.56-1.06) for flavan-3-ols, 0.90 (95% CI, 0.67-1.21) for flavanones, 0.68 (95% CI, 0.50-0.93) for flavones, and 0.69 (95% CI, 0.50-0.95) for flavonols. Allowance for vegetable and fruit consumption only partly explained these inverse relations. Thus, flavonoids, and particularly flavones and flavonols, may account, at least in part, for the favorable role of plant foods on RCC.
Publication
Journal: Journal of Urology
September/14/2006
Abstract
OBJECTIVE
We estimated the prevalence of urinary symptoms related to interstitial cystitis (IC) in women in a primary care practice and confirmed in the United States the results of a Finnish population based prevalence study.
METHODS
Every female patient presenting to our office for a routine office visit between January 9, 2004 and September 24, 2004 was evaluated for urinary symptoms using 2 validated surveys, namely the O'Leary-Sant (OLS) IC symptom and problem index, and the Pelvic Pain and Urgency/Frequency (PUF) patient symptom scale.
RESULTS
Of the 1,218 women in the study group 13 (1.1%) reported severe symptoms and problems (12 or greater on the OLS survey), including 7 (0.6%) who met previously established criteria for probable IC. In the same population scores on the PUF questionnaire indicated that 154 women (12.6%) likely had IC.
CONCLUSIONS
Based on previously published criteria for use of the OLS survey the prevalence of urinary symptoms corresponding to probable IC in our study population (575/100,000 or 0.57%, 95% CI 150 to 1,000) was similar to the 0.45% rate previously reported. However, the results of the PUF questionnaire indicated that the prevalence of IC in women may actually be much higher (12,600/100,000 or 12.6%, 95% CI 10,700 to 14,500). We suggest that the true prevalence of IC in women may be somewhere between these 2 extremes. Further investigation of these questionnaires as screening tools for IC is warranted. IC may be more common in women than previously reported.
Publication
Journal: Dalton Transactions
March/26/2009
Abstract
The enzyme myo-inositol oxygenase (MIOX) catalyzes conversion of myo-inositol (cyclohexan-1,2,3,5/4,6-hexa-ol or MI) to d-glucuronate (DG), initiating the only known pathway in humans for catabolism of the carbon skeleton of cell-signaling inositol (poly)phosphates and phosphoinositides. Recent kinetic, spectroscopic and crystallographic studies have shown that the enzyme activates its substrates, MI and O(2), at a carboxylate-bridged nonheme diiron(ii/iii) cluster, making it the first of many known nonheme diiron oxygenases to employ the mixed-valent form of its cofactor. Evidence suggests that: (1) the Fe(iii) site coordinates MI via its C1 and C6 hydroxyl groups; (2) the Fe(ii) site reversibly coordinates O(2) to produce a superoxo-diiron(iii/iii) intermediate; and (3) the pendant oxygen atom of the superoxide ligand abstracts hydrogen from C1 to initiate the unique C-C-bond-cleaving, four-electron oxidation reaction. This review recounts the studies leading to the recognition of the novel cofactor requirement and catalytic mechanism of MIOX and forecasts how remaining gaps in our understanding might be filled by additional experiments.
Publication
Journal: Biomaterials
April/19/2000
Abstract
Surface-grafted poly(ethylene glycol) (PEG) molecules are known to prevent protein adsorption to the surface. The protein-repulsive property of PEG molecules are maximized by covalent grafting. We have synthesized silanated monomethoxy-PEG (m-PEG) for covalent grafting of PEG to surfaces with oxide layers. Two different trialkoxysilylated PEGs were synthesized and characterized. The first trialkoxysilylated PEG was prepared by direct coupling of m-PEG with 3-isocyanatopropyltriethoxysilane through a urethane bond (silanated PEG I). The other silanated PEG (silanated PEG II) containing a long hydrophobic domain between PEG and a silane domain was prepared by reacting m-PEG with 1,6-diisocyanatohexane and 10-undecen-1-ol in sequence before silylation with 3-mercaptopropyl trimethoxysilane. Silanated PEGs I and II were grafted onto glass, a model surface used in our study. The PEG-grafted glass surfaces were characterized by contact angle, X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). Although contact angle did not change much as the bulk concentration of silanated PEG used for grafting increased from 0.1 to 20 mg/ml for both PEGs I and II, the surface atomic concentrations from XPS measurements showed successful PEG grafting. Surface PEG grafting increased concentration of surface carbon but decreased silicone concentration. The high resolution C1s spectra showed higher ether carbon with lower hydrocarbon compositions for the PEG-grafted surfaces compared to the control surface. AFM images showed that more PEG molecules were grafted onto the surface as the bulk concentration used for grafting was increased. AFM images of the dried surfaces showed that the surfaces were not completely covered by PEG molecules. After hydration, however, the surface appears to be covered completely probably due to the hydration of the grafted PEG chains. Glass surfaces modified with silanated PEGs reduced fibrinogen adsorption by more than 95% as compared with the control surface. Silanated PEGs provides a simple method for PEG grafting to the surface containing oxide layers.
Authors
Publication
Journal: Cancer Research
February/23/1998
Abstract
We evaluated the following (111)In-labeled somatostatin (SS) analogues (diethylenetriaminepentaacetic acid, DTPA; tetraazacyclododecanetetraacetic acid, DOTA): [DTPA0]octreotide, [DTPA0,Tyr3]octreotide, [DTPA0,D-Tyr1]octreotide, [DTPA0,Tyr3]octreotate [Thr(ol) in octreotide replaced with Thr], and [DOTA0,Tyr3]octreotide, in vitro and in vivo. In vitro, all compounds showed high and specific binding to SS receptors in mouse pituitary AtT20 tumor cell membranes, and IC50s were in the nanomolar range. Furthermore, all compounds showed specific internalization in rat pancreatic tumor cells; uptake of [(111)In-DTPA0,Tyr3]octreotate was the highest of the compounds tested, and that of [(111)In-DTPA0,D-Tyr1]octreotide was the lowest. Biodistribution experiments in rats showed that, 4, 24, and 48 h after injection of [(111)In-DTPA0,Tyr3]octreotide, [(111)In-DTPA0,Tyr3]octreotate, and [(111)In-DOTA0,Tyr3]octreotide, radioactivity in the octreotide-binding, receptor-expressing tissues and tumor-to-blood ratios were significantly higher than those after injection of [(111)In-DTPA0]octreotide. Uptake of [(111)In-DTPA0,Tyr3]octreotate in the target organs was also, in vivo, the highest of the radiolabeled peptides tested, whereas that of [(111)In-DTPA0,D-Tyr1]octreotide was the lowest. Uptake of [(111)In-DTPA0,Tyr3]octreotide, [(111)In-DTPA0,Tyr3]octreotate, and [(111)In-DOTA0,Tyr3]octreotide in target tissues was blocked by >90% by 0.5 mg of unlabeled octreotide, indicating specific binding to the octreotide receptors. Blockade of [(111)In-DTPA0,D-Tyr1]octreotide was >70%. In conclusion, radiolabeled [DTPA0,Tyr3]octreotide and, especially, [DTPA0,Tyr3]octreotate and their DOTA-coupled counterparts are most promising for scintigraphy and radionuclide therapy of SS receptor-positive tumors in humans.
Publication
Journal: FASEB Journal
February/8/2004
Abstract
The capacity of the flavan-3-ols [(-)-epicatechin (EC) and (+)-catechin (CT)] and a B dimeric procyanidin (DP-B) to modulate phorbol 12-myristate 13-acetate (PMA)-induced NF-kappaB activation in Jurkat T cells was investigated. The classic PMA-triggered increase in cell oxidants was prevented when cells were preincubated for 24 h with EC, CT, or DP-B (1.7-17.2 microM). PMA induced the phosphorylation of IKKbeta and the subsequent degradation of IkappaBalpha. These events were inhibited in cells pretreated with the flavonoids. PMA induced a 4.6-fold increase in NF-kappaB nuclear binding activity in control cells. Pretreatment with EC, CT, or DP-B decreased PMA-induced NF-kappaB binding activity and the transactivation of the NF-kappaB-driven gene IL-2. EC, CT, and DP-B inhibited, in vitro, NF-kappaB binding to its DNA consensus sequence, but they had no effect on the binding activity of CREB or OCT-1. Thus, EC, CT, or DP-B can influence the immune response by modulating NF-kappaB activation. This modulation can occur at early (regulation of oxidant levels, IKK activation) as well as late (binding of NF-kappaB to DNA) stages of the NF-kappaB activation cascade. A model is presented for possible interactions between DP-B and NF-kappaB proteins, which could lead to the inhibition of NF-kappaB binding to kappaB sites.
Publication
Journal: Diabetes Care
June/11/2012
Abstract
OBJECTIVE
To assess the effect of dietary flavonoids on cardiovascular disease (CVD) risk in postmenopausal women with type 2 diabetes on established statin and hypoglycemic therapy.
METHODS
Despite being medicated, patients with type 2 diabetes have elevated CVD risk, particularly postmenopausal women. Although dietary flavonoids have been shown to reduce CVD risk factors in healthy participants, no long-term trials have examined the additional benefits of flavonoids to CVD risk in medicated postmenopausal women with type 2 diabetes. We conducted a parallel-design, placebo-controlled trial with type 2 diabetic patients randomized to consume 27 g/day (split dose) flavonoid-enriched chocolate (containing 850 mg flavan-3-ols [90 mg epicatechin] and 100 mg isoflavones [aglycone equivalents)]/day) or matched placebo for 1 year.
RESULTS
Ninety-three patients completed the trial, and adherence was high (flavonoid 91.3%; placebo 91.6%). Compared with the placebo group, the combined flavonoid intervention resulted in a significant reduction in estimated peripheral insulin resistance (homeostasis model assessment of insulin resistance [HOMA-IR] -0.3 ± 0.2; P = 0.004) and improvement in insulin sensitivity (quantitative insulin sensitivity index [QUICKI] 0.003 ± 0.00; P = 0.04) as a result of a significant decrease in insulin levels (-0.8 ± 0.5 mU/L; P = 0.02). Significant reductions in total cholesterol:HDL-cholesterol (HDL-C) ratio (-0.2 ± 0.1; P = 0.01) and LDL-cholesterol (LDL-C) (-0.1 ± 0.1 mmol/L; P = 0.04) were also observed. Estimated 10-year total coronary heart disease risk (derived from UK Prospective Diabetes Study algorithm) was attenuated after flavonoid intervention (flavonoid +0.1 ± 0.3 vs. placebo 1.1 ± 0.3; P = 0.02). No effect on blood pressure, HbA(1c), or glucose was observed.
CONCLUSIONS
One-year intervention with flavan-3-ols and isoflavones improved biomarkers of CVD risk, highlighting the additional benefit of flavonoids to standard drug therapy in managing CVD risk in postmenopausal type 2 diabetic patients.
Publication
Journal: Phytochemistry
September/30/2010
Abstract
The distribution of phenolic compounds in young and developing leaves, stems, main and lateral roots and cotyledons of 8-week-old tea (Camellia sinensis) seedlings was investigated using HPLC-MS(2). Fourteen compounds, flavan-3-ols, chlorogenic acids, and kaempferol-O-glycosides, were identified on the basis of their retention time, absorbance spectrum, and MS fragmentation pattern. The major phenolics were (-)-epigallocatechin-3-O-gallate and (-)-epicatechin-3-O-gallate, located principally in the green parts of the seedlings. Considerable amounts of radioactivity from [ring-(14)C]phenylalanine were incorporated in (-)-epicatechin, (-)-epigallocatechin, (-)-epicatechin-3-O-gallate and (-)-epigallocatechin-3-O-gallate, by tissues of young and developing leaves and stems. Expression of genes encoding enzymes involved in flavan-3-ol biosynthesis, CHS, CHI, F3H, F3'5'H, DFR, ANS, ANR and LAR was investigated. Transcripts of all genes, except LAR, were more abundant in leaves and stems than in roots and cotyledons. No significant difference was found in the amount of transcript of LAR. These findings indicate that in tea seedlings flavan-3-ols are produced by a naringenin-chalcone->>naringenin->>dihydrokaempferol pathway. Dihydrokaempferol is a branch point in the synthesis of (-)-epigallocatechin-3-O-gallate and other flavan-3-ols which can be formed by routes beginning with either a flavonoid 3'-hydroxylase mediated conversion of the flavonol to dihydroquercetin or a flavonoid 3',5'-hydroxylase-catalysed conversion to dihydromyricetin with subsequent steps involving sequential reactions catalysed by dihydroflavanol 4-reductase, anthocyanidin synthase, anthocyanidin reductase and flavan-3-ol gallate synthase.
Publication
Journal: American Journal of Clinical Nutrition
February/23/2014
Abstract
BACKGROUND
The timely onset of stage II lactogenesis (OL) is important for successful breastfeeding and newborn health. Several risk factors for delayed OL are common in women with a history of gestational diabetes mellitus (GDM), which may affect their chances for successful breastfeeding outcomes.
OBJECTIVE
We investigated the prevalence and risk factors associated with delayed OL in a racially and ethnically diverse cohort of postpartum women with recent GDM.
METHODS
We analyzed data collected in the Study of Women, Infant Feeding and Type 2 Diabetes After GDM Pregnancy (SWIFT), which is a prospective cohort of women diagnosed with GDM who delivered at Kaiser Permanente Northern California hospitals from 2008 to 2011. At 6-9 wk postpartum, delayed OL was assessed by maternal report of breast fullness and defined as occurring after 72 h postpartum. We obtained data on prenatal course and postdelivery infant feeding practices from electronic medical records and in-person surveys. We used multivariable logistic regression models to estimate associations of delayed OL with prenatal, delivery, and postnatal characteristics.
RESULTS
The analysis included 883 SWIFT participants who initiated breastfeeding and did not have diabetes at 6-9 wk postpartum. Delayed OL was reported by 33% of women and was associated with prepregnancy obesity (OR: 1.56; 95% CI: 1.07, 2.29), older maternal age (OR: 1.05; 95% CI: 1.01, 1.08), insulin GDM treatment (OR: 3.11; 95% CI: 1.37, 7.05), and suboptimal in-hospital breastfeeding (OR: 1.65; 95% CI: 1.20, 2.26). A higher gestational age was associated with decreased odds of delayed OL but only in multiparous mothers (OR: 0.79; 95% CI: 0.67, 0.94).
CONCLUSIONS
One-third of women with recent GDM experienced delayed OL. Maternal obesity, insulin treatment, and suboptimal in-hospital breastfeeding were key risk factors for delayed OL. Early breastfeeding support for GDM women with these risk factors may be needed to ensure successful lactation. This trial was registered at clinicaltrials.gov as NCT01967030.
Publication
Journal: Psychosomatic Medicine
January/10/2011
Abstract
OBJECTIVE
To examine, in a nationally representative sample of U.S. adults, the associations of serum folate, vitamin B-12, and total homocysteine (tHcy) levels with depressive symptoms. Several nutritional and physiological factors have been linked to depression in adults, including low folate and vitamin B-12 and elevated tHcy levels.
METHODS
Data on U.S. adults (age, 20-85 years; n = 2524) from the National Health and Nutrition Examination Survey during the period 2005 to 2006 were used. Depressive symptoms were measured with the Patient Health Questionnaire (PHQ), and elevated symptoms were defined as a PHQ total score of ≥10. Serum folate, vitamin B-12, and tHcy were mainly expressed as tertiles. Multiple ordinary least square (OLS), logistic, and zero-inflated Poisson regression models were conducted in the main analysis.
RESULTS
Overall, mean PHQ score was significantly higher among women compared with men. Elevated depressive symptoms (PHQ score of ≥10) were inversely associated with folate status, particularly among women (fully adjusted odds ratio [tertiles T(3) versus T(1)] = 0.37; 95% confidence interval, 0.17-0.86), but not significantly related to tHcy or vitamin B-12. No interaction was noted between the three exposures in affecting depressive symptoms. In older adults (≥50 years) and both sexes combined, tHcy was positively associated with elevated depressive symptoms (fully adjusted odds ratio [tertiles T(2) versus T(1)] = 3.01; 95% confidence interval, 1.01-9.03), although no significant dose-response relationship was found.
CONCLUSIONS
Future interventions to improve mental health outcomes among U.S. adults should take into account dietary and other factors that would increase levels of serum folate.
Publication
Journal: Arzneimittel-Forschung
November/27/1986
Abstract
The absolute bioavailability of tramadol hydrochloride (rac-1(e)-(m-methoxyphenyl)-2-(e)-(dimethylaminomethyl)cyclohexan- 1(a)-ol hydrochloride, CG 315) after the oral administration of Tramal capsules was determined in a balanced cross-over study in 10 male volunteers. Each volunteer received two single doses of 100 mg tramadol hydrochloride, one by oral (2 Tramal capsules) and one by intravenous route (2 ampoules of Tramal 50 solution for injection). The formulations were administered in the morning on an empty stomach, and the interval between the two applications was one week. Serum concentrations of tramadol were determined by gas chromatography-mass spectrometry and the bioavailability was ascertained by calculation of the areas under the serum concentration curves. The absolute bioavailability of tramadol in Tramal capsules was 68 +/- 13% (means +/- SD; n = 10) with a range of 41-84% and a 95% confidence interval of 55.0-79.2%. The areas under the serum concentration curves of tramadol hydrochloride (AUC) were 2488 +/- 774 ng X h/ml (p.o.) and 3709 +/- 977 ng X h/ml (i.v.). Peak serum concentrations of 280 +/- 49 ng/ml were reached 2 h after oral administration of two Tramal capsules; a serum concentration of 100 ng/ml (assumed as the threshold value for analgesic efficacy) was reached after 0.68 +/- 0.17 h and was maintained for 9.0 +/- 2.2 h. The half-life of absorption was 0.38 +/- 0.18 h and the lag-time 0.48 +/- 0.14 h. In the terminal phase the biological half-lives of tramadol were 5.1 +/- 0.8 h (p.o.) and 5.2 +/- 0.8 h (i.v.).(ABSTRACT TRUNCATED AT 250 WORDS)
Publication
Journal: BMC Plant Biology
April/29/2013
Abstract
BACKGROUND
Sclareol is a diterpene natural product of high value for the fragrance industry. Its labdane carbon skeleton and its two hydroxyl groups also make it a valued starting material for semisynthesis of numerous commercial substances, including production of Ambrox® and related ambergris substitutes used in the formulation of high end perfumes. Most of the commercially-produced sclareol is derived from cultivated clary sage (Salvia sclarea) and extraction of the plant material. In clary sage, sclareol mainly accumulates in essential oil-producing trichomes that densely cover flower calices. Manool also is a minor diterpene of this species and the main diterpene of related Salvia species.
RESULTS
Based on previous general knowledge of diterpene biosynthesis in angiosperms, and based on mining of our recently published transcriptome database obtained by deep 454-sequencing of cDNA from clary sage calices, we cloned and functionally characterized two new diterpene synthase (diTPS) enzymes for the complete biosynthesis of sclareol in clary sage. A class II diTPS (SsLPPS) produced labda-13-en-8-ol diphosphate as major product from geranylgeranyl diphosphate (GGPP) with some minor quantities of its non-hydroxylated analogue, (9 S, 10 S)-copalyl diphosphate. A class I diTPS (SsSS) then transformed these intermediates into sclareol and manool, respectively. The production of sclareol was reconstructed in vitro by combining the two recombinant diTPS enzymes with the GGPP starting substrate and in vivo by co-expression of the two proteins in yeast (Saccharomyces cerevisiae). Tobacco-based transient expression assays of green fluorescent protein-fusion constructs revealed that both enzymes possess an N-terminal signal sequence that actively targets SsLPPS and SsSS to the chloroplast, a major site of GGPP and diterpene production in plants.
CONCLUSIONS
SsLPPS and SsSS are two monofunctional diTPSs which, together, produce the diterpenoid specialized metabolite sclareol in a two-step process. They represent two of the first characterized hydroxylating diTPSs in angiosperms and generate the dihydroxylated labdane sclareol without requirement for additional enzymatic oxidation by activities such as cytochrome P450 monoxygenases. Yeast-based production of sclareol by co-expresssion of SsLPPS and SsSS was efficient enough to warrant the development and use of such technology for the biotechnological production of scareol and other oxygenated diterpenes.
Publication
Journal: Molecular Nutrition and Food Research
February/16/2010
Abstract
Apples (Malus spp., Rosaceae) and products thereof contain high amounts of polyphenols which show diverse biological activities and may contribute to beneficial health effects, like protecting the intestine against inflammation initiated by chronic inflammatory bowel diseases (IBD). IBD are characterized by an excessive release of several proinflammatory cytokines and chemokines by different cell types which results consequently in an increased inflammatory response. In the present study we investigated the preventive effectiveness of polyphenolic juice extracts and single major constituents on inflammatory gene expression in immunorelevant human cell lines (DLD-1, T84, MonoMac6, Jurkat) induced with specific stimuli. Besides the influence on proinflammatory gene expression, the effect on NF-kappaB-, IP-10-, IL-8-promoter-, STAT1-dependent signal transduction, and the relative protein levels of multiple released cytokines and chemokines were studied. DNA microarray analysis of several genes known to be strongly regulated during gastrointestinal inflammation, combined with quantitative real-time PCR (qRT-PCR) revealed that the apple juice extract AE04 (100-200 microg/mL) significantly inhibited the expression of NF-kappaB regulated proinflammatory genes (TNF-alpha, IL-1beta, CXCL9, CXCL10), inflammatory relevant enzymes (COX-2, CYP3A4), and transcription factors (STAT1, IRF1) in LPS/IFN-gamma stimulated MonoMac6 cells without significant effects on the expression of house-keeping genes. A screening of some major compounds of AE04 revealed that the flavan-3-ol dimer procyanidin B(2 )is mainly responsible for the anti-inflammatory activity of AE04. Furthermore, the dihydrochalcone aglycone phloretin and the dimeric flavan-3-ol procyanidin B(1 )significantly inhibited proinflammatory gene expression and repressed NF-kappaB-, IP-10-, IL-8-promoter-, and STAT1-dependent signal transduction in a dose-dependent manner. The influence on proinflammatory gene expression by the applied polyphenols thereby strongly correlated with the increased protein levels investigated by human cytokine array studies. In summary, we evaluated selected compounds responsible for the anti-inflammatory activity of AE04. In particular, procyanidin B(1), procyanidin B(2), and phloretin revealed anti-inflammatory activities in vitro and therefore may serve as transcription-based inhibitors of proinflammatory gene expression.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
February/27/1991
Abstract
Opioids and opioid peptides have been shown by numerous laboratories to modulate various parameters of the immune response, but little attention has been given to the type of opioid receptor that might be involved. This study focuses on the in vitro influences of morphine and DAMGE (Tyr-D-Ala-Gly-N-Me-Phe-Gly-ol), mu-selective agonists, and U50,488H and U69,593, kappa-selective agonists, on the generation of antibody to sheep erythrocytes in vitro. It was found that the mu and kappa opioid agonists were able to inhibit the capacity of murine lymphoid cells to generate antibody at concentrations as low as 10(-10) M. The effects were almost completely blocked by pretreatment with naloxone or naltrexone, opioid-specific antagonists. Only the kappa-agonist activity was abrogated by pretreatment with norbinaltorphimine, a kappa-specific antagonist. The stereospecificity of the kappa effect was demonstrated using isomers of U50,488H, with the (-) form possessing significantly greater immunomodulatory activity. Additional studies, using a mu receptor-deficient mouse strain, demonstrated that only the kappa agonists were capable of suppressing antibody responses, whereas mu- and kappa-selective agonists suppressed the parent mu-responsive strain. Our results clearly indicate that mu and kappa opioid receptors are involved in regulation of lymphoid cell production of antibodies.
Publication
Journal: Oncogene
September/4/2017
Abstract
Alterations in long non-coding RNAs (lncRNAs) are associated with human carcinogenesis. One group of lncRNAs, which are antisense in orientation to coding mRNAs (ASs), have been recently described in cancers but are poorly understood. We sought to identify ASs involved in human gastric cancer (GC) and to elucidate their mechanisms of action in carcinogenesis. We performed massively parallel RNA sequencing in GCs and matched normal tissues, as well as in GC-derived and normal gastric epithelial cell lines. One AS, designated Homo sapiens keratin 7 (KRT7-AS), was selected due to its marked upregulation and concordant expression with its cognate sense counterpart, KRT7, in GC tissues and cell lines. KRT7-AS formed an RNA-RNA hybrid with KRT7 and controlled KRT7 expression at both the mRNA and the post-transcriptional levels. Moreover, forced overexpression of the KRT7-overlapping region (OL) of KRT7-AS (but not its non-KRT7-OL portions) increased keratin 7 protein levels in cells. Finally, forced overexpression of full-length KRT7-AS or OL KRT7-AS (but not its non-KRT7-OL regions) promoted GC cell proliferation and migration. We conclude that lncRNA KRT7-AS promotes GC, at least in part, by increasing KRT7 expression.
Publication
Journal: Proceedings of the National Academy of Sciences of the United States of America
November/29/2010
Abstract
Precise control of alternative splicing governs oligodendrocyte (OL) differentiation and myelination in the central nervous system (CNS). A well-known example is the developmentally regulated expression of splice variants encoding myelin-associated glycoprotein (MAG), which generates two protein isoforms that associate with distinct cellular components crucial for axon-glial recognition during myelinogenesis and axon-myelin stability. In the quakingviable (qk(v)) hypomyelination mutant mouse, diminished expression of isoforms of the selective RNA-binding protein quaking I (QKI) leads to severe dysregulation of MAG splicing. The nuclear isoform QKI-5 was previously shown to bind an intronic element of MAG and modulate alternative exon inclusion from a MAG minigene reporter. Thus, QKI-5 deficiency was thought to underlie the defects of MAG splicing in the qk(v) mutant. Surprisingly, we found that transgenic expression of the cytoplasmic isoform QKI-6 in the qk(v) OLs completely rescues the dysregulation of MAG splicing without increasing expression or nuclear abundance of QKI-5. In addition, cytoplasmic QKI-6 selectively associates with the mRNA that encodes heterogeneous nuclear ribonucleoprotein A1 (hnRNPA1), a well-characterized splicing factor. Furthermore, QKI deficiency in the qk(v) mutant results in abnormally enhanced hnRNPA1 translation and overproduction of the hnRNPA1 protein but not hnRNPA1 mRNA, which can be successfully rescued by the QKI-6 transgene. Finally, we show that hnRNPA1 binds MAG pre-mRNA and modulates alternative inclusion of MAG exons. Together, these results reveal a unique cytoplasmic pathway in which QKI-6 controls translation of the splicing factor hnRNPA1 to govern alternative splicing in CNS myelination.
Publication
Journal: Physiology and Behavior
October/24/2001
Abstract
We examined the physiological and psychological effects of nanomolar amounts of steroids applied directly under the nose (Delta4,16-androstadien-3-one and 1,3,5,(10),16-estratetraen-3-ol). These potential human chemosignals were not consciously discernible in a strong-odor carrier (clove oil and propylene glycol). In a double-blind, within-subject, repeated-measures experiment with 65 subjects, we demonstrated that both steroids produced sustained changes in digit skin temperature and palmar skin conductance (an indicator of sympathetic nervous system tone) while the subjects were completing psychological questionnaires or reading. These effects, however, did not follow the sex-stereotyped pattern predicted by a sex attractant function. Both androstadienone and estratetraenol raised the skin temperature of men's hands and lowered it in women. Likewise, each steroid increased skin conductance, with a significantly greater effect on women than men. Women's responses were observed only in the sessions run by the male tester, an effect that may or may not be solely attributable to tester sex. Men's responses, in contrast, were not affected by this difference in socioexperimental condition. Similarly, women experienced an immediate increase in positive mood only in the presence of the male tester, while men's responses were unaffected by this socioexperimental context. One source of this sex difference may be the fact that the majority of women were in the late follicular phase of their menstrual cycle. Although it is premature to classify these steroids as pheromones, our data suggest that they function as chemosignals that modulate autonomic nervous system tone as well as psychological state.
Publication
Journal: Medical Decision Making
June/29/2010
Abstract
BACKGROUND
Mapping disease-specific instruments into generic health outcomes or utility values is an expanding field of interest in health economics. This article constructs an algorithm to translate the modified Rankin scale (mRS) into EQ-5D utility values.
METHODS
mRS and EQ-5D information was derived from stroke or transient ischemic attack (TIA) patients identified as part of the Oxford Vascular study (OXVASC). Ordinary least squares (OLS) regression was used to predict UK EQ-5D tariffs from mRS scores. An alternative method, using multinomial logistic regression with a Monte Carlo simulation approach (MLogit) to predict responses to each EQ-5D question, was also explored. The performance of the models was compared according to the magnitude of their predicted-to-actual mean EQ-5D tariff difference, their mean absolute and mean squared errors (MAE and MSE), and associated 95% confidence intervals (CIs). Out-of-sample validation was carried out in a subset of coronary disease and peripheral vascular disease (PVD) patients also identified as part of OXVASC but not used in the original estimation.
RESULTS
The OLS and MLogit yielded similar MAE and MSE in the internal and external validation data sets. Both approaches also underestimated the uncertainty around the actual mean EQ-5D tariff producing tighter 95% CIs in both data sets.
CONCLUSIONS
The choice of algorithm will be dependent on the study aim. Individuals outside the United Kingdom may find it more useful to use the multinomial results, which can be used with different country-specific tariff valuations. However, these algorithms should not replace prospective collection of utility data.
Publication
Journal: Journal of Neuroscience
December/18/2007
Abstract
The myelin basic protein (MBP) gene encodes two families of proteins: the classic MBP constituents of myelin and the golli-MBPs, the function of which is less well understood. Previous work suggests that golli proteins may play a role in Ca2+ homeostasis in oligodendrocytes (OLs) and in T-cells. Overexpression of golli in OL cell lines induces elaboration of sheets and processes. Live imaging of these cells revealed a rapid retraction of the processes and sheets after depolarization with high K+. This phenomenon was associated with a significant increase in [Ca2+]int without changes in cell viability. The results indicated that golli produced its effect through Ca2+ influx, rather than Ca2+ release from intracellular stores. Furthermore, a specific [Ca2+]int chelator (BAPTA) or Cd2+, a specific blocker of voltage-operated Ca2+ channels, abolished the ability of golli to promote process extension in a dose-dependent manner. Analysis of the golli protein identified a myristoylation site at the C terminus of the golli domain, which was essential for the action of golli on Ca2+ influx, suggesting that binding of golli to the plasma membrane is important for modulating Ca2+ homeostasis. High-resolution spatiotemporal analysis along N19 processes revealed higher-amplitude local Ca2+ influx in regions with elevated levels of golli. These findings suggest a key role for golli proteins in regulating voltage-gated Ca2+ channels in OLs during process remodeling. Our observations are consistent with the hypothesis that golli proteins, as a part of a protein complex, modulate Ca2+ influx at the plasma membrane and along OL processes.
Publication
Journal: Journal of Pharmacology and Experimental Therapeutics
January/5/1994
Abstract
Rhesus monkeys were trained to respond under a fixed-ratio 30 schedule of food reinforcement. The mu opioid agonists alfentanil and fentanyl, the kappa opioid agonists ethylketocyclazocine (EKC) and U69,593, the delta opioid agonist BW373U86 [(+-)-4-((R*)-a-((2S*5R*)-4-allyl-2,5-dimethyl-1-piperazinal)-3-h ydroxy- benzyl)-N,N-diethylbenzamide dihydrochloride] and the nonopioid, noncompetitive N-methyl-D-aspartate antagonist ketamine all produced a dose-dependent decrease in rates of responding. Quadazocine (0.1-10 mg/kg) antagonized the rate-decreasing effects of all the opioid agonists, but not of ketamine. The in vivo apparent pA2 values (95% CL) for quadazocine in combination with each agonist were: alfentanil, 7.7 (7.6-7.8); fentanyl, 7.7 (7.6-7.8); EKC, 6.3 (5.9-6.7); U69,593, 6.5 (5.9-7.0); and BW373U86, 5.5 (5.3-5.8). Additionally, antagonist effects of individual doses of quadazocine in combination with each agonist were evaluated by using in vivo apparent pKB analysis, and pKB values were found to be similar to the more rigorously determined pA2 values. The relative pA2 and pKB values of quadazocine in antagonizing the rate-decreasing effects of mu, kappa and delta opioid agonists corresponded to the relative potency of quadazocine in displacing the specific binding of the mu agonist [3H]Tyr-D-Ala-Gly-(Me)-Phe-Gly-ol (IC50 = 0.080 nM), the kappa agonist [3H]U69,593 (IC50 = 0.52 nM) and the delta agonist [D-Pen2,D-Pen5]-[3H]enkephalin (IC50 = 4.6 nM) from binding sites in membranes from monkey brain cortex.(ABSTRACT TRUNCATED AT 250 WORDS)
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