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1.
Am J Physiol Heart Circ Physiol ; 318(6): H1461-H1473, 2020 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-32383991

RESUMO

There is a sharp rise in cardiovascular disease (CVD) risk and progression with the onset of menopause. The 4-vinylcyclohexene diepoxide (VCD) model of menopause recapitulates the natural, physiological transition through perimenopause to menopause. We hypothesized that menopausal female mice were more susceptible to CVD than pre- or perimenopausal females. Female mice were treated with VCD or vehicle for 20 consecutive days. Premenopausal, perimenopausal, and menopausal mice were administered angiotensin II (ANG II) or subjected to ischemia-reperfusion (I/R). Menopausal females were more susceptible to pathological ANG II-induced cardiac remodeling and cardiac injury from a myocardial infarction (MI), while perimenopausal, like premenopausal, females remained protected. Specifically, ANG II significantly elevated diastolic (130.9 ± 6.0 vs. 114.7 ± 6.2 mmHg) and systolic (156.9 ± 4.8 vs. 141.7 ± 5.0 mmHg) blood pressure and normalized cardiac mass (15.9 ± 1.0 vs. 7.7 ± 1.5%) to a greater extent in menopausal females compared with controls, whereas perimenopausal females demonstrated a similar elevation of diastolic (93.7 ± 2.9 vs. 100.5 ± 4.1 mmHg) and systolic (155.9 ± 7.3 vs. 152.3 ± 6.5 mmHg) blood pressure and normalized cardiac mass (8.3 ± 2.1 vs. 7.5 ± 1.4%) compared with controls. Similarly, menopausal females demonstrated a threefold increase in fibrosis measured by Picrosirus red staining. Finally, hearts of menopausal females (41 ± 5%) showed larger infarct sizes following I/R injury than perimenopausal (18.0 ± 5.6%) and premenopausal (16.2 ± 3.3, 20.1 ± 4.8%) groups. Using the VCD model of menopause, we provide evidence that menopausal females were more susceptible to pathological cardiac remodeling. We suggest that the VCD model of menopause may be critical to better elucidate cellular and molecular mechanisms underlying the transition to CVD susceptibility in menopausal women.NEW & NOTEWORTHY Before menopause, women are protected against cardiovascular disease (CVD) compared with age-matched men; this protection is gradually lost after menopause. We present the first evidence that demonstrates menopausal females are more susceptible to pathological cardiac remodeling while perimenopausal and cycling females are not. The VCD model permits appropriate examination of how increased susceptibility to the pathological process of cardiac remodeling accelerates from pre- to perimenopause to menopause.


Assuntos
Remodelamento Atrial/fisiologia , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/fisiopatologia , Cicloexenos , Menopausa/fisiologia , Compostos de Vinila , Angiotensina II , Animais , Doenças Cardiovasculares/induzido quimicamente , Feminino , Camundongos , Modelos Animais
2.
Nature ; 581(7808): 288-293, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32433618

RESUMO

The hydrogen isotopes deuterium (D) and tritium (T) have become essential tools in chemistry, biology and medicine1. Beyond their widespread use in spectroscopy, mass spectrometry and mechanistic and pharmacokinetic studies, there has been considerable interest in incorporating deuterium into drug molecules1. Deutetrabenazine, a deuterated drug that is promising for the treatment of Huntington's disease2, was recently approved by the United States' Food and Drug Administration. The deuterium kinetic isotope effect, which compares the rate of a chemical reaction for a compound with that for its deuterated counterpart, can be substantial1,3,4. The strategic replacement of hydrogen with deuterium can affect both the rate of metabolism and the distribution of metabolites for a compound5, improving the efficacy and safety of a drug. The pharmacokinetics of a deuterated compound depends on the location(s) of deuterium. Although methods are available for deuterium incorporation at both early and late stages of the synthesis of a drug6,7, these processes are often unselective and the stereoisotopic purity can be difficult to measure7,8. Here we describe the preparation of stereoselectively deuterated building blocks for pharmaceutical research. As a proof of concept, we demonstrate a four-step conversion of benzene to cyclohexene with varying degrees of deuterium incorporation, via binding to a tungsten complex. Using different combinations of deuterated and proteated acid and hydride reagents, the deuterated positions on the cyclohexene ring can be controlled precisely. In total, 52 unique stereoisotopomers of cyclohexene are available, in the form of ten different isotopologues. This concept can be extended to prepare discrete stereoisotopomers of functionalized cyclohexenes. Such systematic methods for the preparation of pharmacologically active compounds as discrete stereoisotopomers could improve the pharmacological and toxicological properties of drugs and provide mechanistic information related to their distribution and metabolism in the body.


Assuntos
Benzeno/química , Técnicas de Química Sintética , Cicloexenos/química , Cicloexenos/síntese química , Deutério/química , Preparações Farmacêuticas/química , Preparações Farmacêuticas/síntese química , Bases de Dados de Compostos Químicos , Cinética , Estrutura Molecular , Estereoisomerismo , Tetrabenazina/análogos & derivados , Tetrabenazina/síntese química , Tetrabenazina/química , Tungstênio/química
3.
Phytochem Anal ; 31(5): 564-574, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31997502

RESUMO

INTRODUCTION: Saffron (Crocus sativus L.) is a well-known spice which is used as the colourant and flavouring agent in food products. Safranal could act as an indicator for saffron grading, authentication and adulteration, as well as for quality evaluation of saffron flavoured products; since it is the main odourant and the most aroma-active compound of saffron. OBJECTIVES: Firstly, determination of the optimum static conditions for safranal extraction through headspace solid-phase micro-extraction combined with gas chromatography (HS-SPME-GC) technique. Secondly, safranal measurement in different saffron flavoured products under the optimised static conditions. Thirdly, elucidation of the method efficiency for safranal measurement under non-equilibrium conditions for a saffron drink sample. METHODS: Different equilibrium times, pH and salt concentrations were applied on aqueous solutions of safranal. Accordingly, the optimised static conditions were determined for safranal extraction through HS-SPME-GC approach using polydimethylsiloxane (PDMS) fibre. RESULTS: Under static conditions, a linear response was obtained for standard curve within the safranal concentration range of 0.08-30 ppm, with R2 = 0.9999. The limits of detection and quantification were 0.04 and 0.08 ppm, respectively. Despite the fact that safranal peak area was an efficient parameter for quantifications under static conditions; its poor reproducibility was proved under dynamic conditions for the saffron drink sample. This observation necessitated application of kinetic studies on real food samples. CONCLUSIONS: Safranal extraction was successfully performed from aqueous matrices through HS-SPME-GC, under static conditions. Mathematical modelling resulted in kinetic parameters that improved the efficiency of safranal measurement under dynamic conditions, using PDMS fibre.


Assuntos
Benzenossulfonatos , Cromatografia Gasosa , Cicloexenos , Cromatografia Gasosa-Espectrometria de Massas , Cinética , Reprodutibilidade dos Testes , Terpenos
4.
Food Chem ; 307: 125527, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648179

RESUMO

We report on a sensitive and fast quantitative MALDI-MS/MS method used to assess saffron authenticity by direct analysis through the determination of picrocrocin as the saffron authenticity marker, and using curcumin as the non-isotopic isobaric internal standard. The internal standard curcumin yielded good linearity (R2 = 0.994), and with confidence intervals at 95% for intercept. The detectable maximum adulteration percentage (99.0%) was estimated interpolating the limit of detection (LOD) for the isobaric internal standard in linear regression. The LOD was 47.63 ppm, and LOQ was 56.53 ppm. Good accuracy and precision were obtained for all concentrations. The capability of the MS approach to monitor analytes in a specific, selective fashion was used to obtain a semi-quantitative adulteration percentage and to establish the adulterant by additional experiments. The detection of gardecin and its derivatives in commercial samples indicated that Gardenia jasminoides Ellis was used as the adulterant.


Assuntos
Crocus/química , Cicloexenos/análise , Glucosídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Terpenos/análise , Calibragem , Curcumina/química , Cicloexenos/normas , Glucosídeos/normas , Limite de Detecção , Modelos Lineares , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/normas , Terpenos/normas
5.
BMC Pharmacol Toxicol ; 20(Suppl 1): 83, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31852533

RESUMO

BACKGROUND: Exposure to vinylcyclohexene (VCH) and methylmercury (MeHg+) can induce oxidative stress and gene modulation. Several studies have been evaluating the effects of VCH and MeHg+, but little is known about interactive effects between them. This work aimed to assess the exposure and co-exposure effects of MeHg+ and VCH on oxidative stress and gene modulation in Drosophila melanogaster. METHODS: Reactive species production, glutathione S-transferase (GST) and acetylcholinesterase (AChE) activities were evaluated after exposure and co-exposure to VCH (1 mM) and MeHg+ (0.2 mM) for one or three days in the head and body (thorax and abdomen) of flies. The expression of genes related to redox state and inflammatory response was evaluated after exposure and co-exposure to VCH and MeHg+ for three days. RESULTS: Survival decreased only in flies co-exposed to VCH and MeHg+ for three days. All treatments increased total reactive species production after one day of exposure. However, no significant changes were observed in the head after three days of exposure. One day of exposure to VCH caused an increase in the head GST activity, whereas MeHg+ induced an increase after three days of exposure. Regarding the body, all treatments increased GST activity after one day of exposure, but only the flies exposed to MeHg+ presented an increase in GST activity after three days of exposure. Treatments did not alter AChE activity in the head. As for gene expression, there was a significant increase in the Relish transcription factor gene in the flies' body, but Nrf2, Keap1, Jafrac1, TrxR1, and NF-κß were not altered. CONCLUSION: The results suggest that exposure to VCH and MeHg+ induce oxidative stress and activation of an inflammatory response in fruit flies.


Assuntos
Cicloexenos/toxicidade , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Acetilcolinesterase/genética , Acetilcolinesterase/metabolismo , Animais , Cicloexenos/administração & dosagem , Relação Dose-Resposta a Droga , Proteínas de Drosophila/genética , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Sinergismo Farmacológico , Glutationa Transferase/genética , Glutationa Transferase/metabolismo , Compostos de Metilmercúrio/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética
6.
PLoS One ; 14(12): e0226874, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31887176

RESUMO

During the transition to menopause, women experience a variety of physical and psychological symptoms that are directly or indirectly linked to changes in hormone secretion. Establishing animal models with intact ovaries is essential for understanding these interactions and finding new therapeutic targets. In this study, we assessed the endocrine profile, as well as the estrous cycle, in the 4-vinylcyclohexene diepoxide (VCD)-induced follicular depletion rat model in 10-day intervals over 1 month to accurately establish the best period for studies of the transition period. Twenty-eight-day-old female rats were injected daily with VCD or oil s.c. for 15 days and euthanized in the diestrus phase approximately 70, 80, 90 and 100 days after the onset of treatment. The percentage of rats showing irregular cycles and the plasma level of FSH increased only in the 100-day VCD group. Plasma anti-Müllerian hormone (AMH) and progesterone were lower in all VCD groups compared to control groups, while estradiol remained unchanged or higher. As in control groups, dihydrotestosterone (DHT) progressively decreased in the 70-90-day VCD groups; however, it was followed by a sharp increase only in the 100-day VCD group. No changes were found in plasma corticosterone, prolactin, thyroid hormones or luteinizing hormone. Based on the estrous cycle and endocrine profile, we conclude that 1) the time window from 70 to 100 days is suitable to study a perimenopause-like state in this model, and 2) regular cycles with low progesterone and AMH and normal FSH can be used as markers of the early/mid-transition period, whereas irregular cycles associated with higher FSH and DHT can be used as markers of the late transition period to estropause.


Assuntos
Sistema Endócrino/química , Perimenopausa/sangue , Animais , Hormônio Antimülleriano/sangue , Biomarcadores/sangue , Cicloexenos , Di-Hidrotestosterona/sangue , Ciclo Estral/sangue , Feminino , Hormônio Foliculoestimulante/sangue , Modelos Animais , Progesterona/sangue , Ratos , Fatores de Tempo , Compostos de Vinila
7.
Zhongguo Ying Yong Sheng Li Xue Za Zhi ; 35(4): 312-316, 2019 Jul 28.
Artigo em Chinês | MEDLINE | ID: mdl-31701713

RESUMO

OBJECTIVE: To investigate the effects and molecular mechanisms of 2-12alkyl-6-methoxycyclohexa-2,5-diene-1,4-dione(DMDD) on diffuse large B lymphoma (DLBCL). METHODS: In animal experiments, 4-week-aged BALB/C mice were divided into 5 groups, 20 mice in each group. Mice were inguinal injected with DLBCL cell line OCI-LY19 cells 0.1 ml at the concention of 1 × 107 /ml. Two days later, mice were treated with DMDD at the doses of 0, 1, 5, 25 and 125 mg/kg by intragastric administration respectively, once /2 days. Ten mice of each group were killed on the 18th day of administration, and the tumor tissues were weighed. The survival time of the remaining mice were recorded. In cell experiments, OCI-LY19 cells were added to 96-well culture plates, 100 µl 1×105 cells/ml per well, then 100 µl DMDD was added to the well and the final concentrations were 0, 1, 5, 25 and 125 µmol/L respectively. The cells were treated with DMDD for 0, 24, 48 and 72 h, three wells in each group. The cell proliferation activity was detected by MTS assay. According to the results of cell proliferation experiments, OCI-LY19 cells were treated with DMDD at the concentrations of 0 µmol/L, 5 µmol/L and 25 µmol/L for 24 h. The apoptosis rate was analyzed by flow cytometry, the nuclear type was observed by hoechst staining, the mitochondrial membrane potential was observed by JC-1 staining, cytotoxicity of drugs was evaluated by LDH release experiment, gene expression and transcription were analyzed by qPCR and Western blot. RESULTS: Compared with 0 mg/kg drug group, DMDD at the dose of 1~125 mg/kg could inhibit the growth of tumor tissue in mice and prolong their survival time (P<0.01). Cell experiments showed: in DMDD group, the proliferation activity of OCI-LY19 cells was decreased significantly and the level of apoptosis was increased significantly (P<0.01), nuclear fragmentation, agglutination, apoptotic bodies occurred and mitochondrial membrane potential was decreased, the LDH release rate was increased significantly (P<0.01), the expressions of caspase-3 and bax genes and the phosphorylation level of Ikappa B alpha in cells were up-regulated significantly, the protein expression levels of bcl-2, bcl-xL, jak2 and stat3 were inhibited significantly (P<0.01). CONCLUSION: DMDD can inhibit the expressions of JAK2, STAT3 and p-Ikappa B alpha in JAK2/STAT3 and NF-kappa B signal pathways, down-regulate BCL-2/BAX and activate Caspase-3, finally, activate the endogenous pathway of mitochondrial apoptosis in OCI-LY19 cells and promote the apoptosis of DLBCL cells, inhibit proliferation of OCI-LY19 cells. It has inhibitive effects on DLBCL.


Assuntos
Apoptose , Cicloexenos/farmacologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Animais , Linhagem Celular Tumoral , Proliferação de Células , Linfoma Difuso de Grandes Células B/patologia , Camundongos , Camundongos Endogâmicos BALB C
8.
Nat Commun ; 10(1): 5060, 2019 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-31699986

RESUMO

Engineered enzyme cascades offer powerful tools to convert renewable resources into value-added products. Man-made catalysts give access to new-to-nature reactivities that may complement the enzyme's repertoire. Their mutual incompatibility, however, challenges their integration into concurrent chemo-enzymatic cascades. Herein we show that compartmentalization of complex enzyme cascades within E. coli whole cells enables the simultaneous use of a metathesis catalyst, thus allowing the sustainable one-pot production of cycloalkenes from oleic acid. Cycloheptene is produced from oleic acid via a concurrent enzymatic oxidative decarboxylation and ring-closing metathesis. Cyclohexene and cyclopentene are produced from oleic acid via either a six- or eight-step enzyme cascade involving hydration, oxidation, hydrolysis and decarboxylation, followed by ring-closing metathesis. Integration of an upstream hydrolase enables the usage of olive oil as the substrate for the production of cycloalkenes. This work highlights the potential of integrating organometallic catalysis with whole-cell enzyme cascades of high complexity to enable sustainable chemistry.


Assuntos
Biocatálise , Cicloparafinas/síntese química , Ácidos Dicarboxílicos , Escherichia coli , Ácido Oleico , Azeite de Oliva , Cicloexenos/síntese química , Ciclopentanos/síntese química , Descarboxilação , Hidrólise , Compostos Organometálicos , Oxirredução , Biologia Sintética
9.
Environ Sci Process Impacts ; 21(10): 1713-1721, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31588946

RESUMO

Photodegradation can be an important abiotic degradation process to consider for the fate and persistence assessment of chemical substances in the environment. In this work, using a fragrance ingredient (FI, (E)-4-(2,2,3,6-tetramethylcyclohexyl)but-3-en-2-one) as an example, we developed a streamlined workflow to investigate direct photodegradation of chemicals in the aquatic environment, including laboratory investigation of kinetics and transformation products and estimation of its aquatic environmental half-lives. Direct photodegradation was determined to be the dominant photodegradation process for FI with a quantum yield of 0.25, which was supported by photodegradation experiments conducted in natural sunlight. Accounting for light attenuation by dissolved organic matter in natural waters of different depths resulted in aquatic half-lives of <31 days even at polar latitudes. Photoisomerization was shown to be a major photodegradation pathway along with the formation and subsequent degradation of constitutional isomers and photooxidation products. These results contributed to FI being assessed as non-persistent in the environment.


Assuntos
Cicloexenos/química , Odorantes/análise , Fotólise , Poluentes Químicos da Água/química , Cicloexenos/análise , Cicloexenos/efeitos da radiação , Meia-Vida , Cinética , Luz Solar , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/efeitos da radiação , Fluxo de Trabalho
10.
Bioresour Technol ; 294: 122180, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31606595

RESUMO

The biotransformation of R-(+)-limonene into high concentrations of R-(+)-α-terpineol by Sphingobium sp. was investigated in order to optimize the main process variables (pH, biocatalyst concentration, substrate concentration, temperature and agitation). This strategy comprised the screening of variables by a Plackett-Burman design followed by a Central Composite Design. The statistical analysis showed that the optimal α-terpineol production were at 28 °C and pH 7.0, with a limonene concentration of 350 g/L of organic phase agitation of 200 rpm and a biocatalyst concentration of 2.8 g/L of aqueous phase (OD600 = 8). Further trials showed that the R-(+)-α-terpineol concentration was higher (240 g/L after 96 h) when using a ratio of 1:3 (v.v-1) of organic:aqueous phases. However, the total production and yield (in terms of biomass) of α-terpineol would be maximized for an aqueous:organic ratio of 1:1. The experimental design optimization adopted herein was an effective tool for this type of study.


Assuntos
Limoneno , Terpenos , Biotransformação , Monoterpenos Cicloexânicos , Cicloexenos , Monoterpenos
11.
Org Biomol Chem ; 17(37): 8628-8635, 2019 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31528943

RESUMO

Nucleophilic ring opening of cyclohexene oxides is known to proceed preferentially through the trans-diaxial pathway (the Fürst-Plattner rule). This preference, however, is not absolute, and can be affected by substituents on the cyclohexene oxide ring, as illustrated by LiAlH4 ring-opening of the cis- and trans-isomers of 4-t-butyl- and 3-methylcyclohexene oxide (cis- and trans-1, cis- and trans-2). We performed B3LYP/6-31+G*(PCM) geometry optimizations to locate the chair-like and twist-boat-like transition structures for the hydride attacks on the pseudoaxial and pseudoequatorial conformers of these epoxides. Our calculations are consistent with the experimental observation of effective Fürst-Plattner control of AlH4--opening of cis-1, trans-1, and cis-2, but low selectivity in ring-opening of trans-2. Our data at B3LYP/6-31+G*(PCM) suggests this reduction in selectivity is due to a diminished pseudoequatorial preference of the 3-methyl group in trans-2 relative to that in cis-2. The two calculated chair-like transition structures for hydride opening of trans-2 differ in activation energy free energy (ΔΔG‡) by only 0.4 kcal mol-1. Thus, these calculations account for the reduced regioselectivity of ring opening seen for trans-2 by AlH4- and other nucleophiles.


Assuntos
Compostos de Alumínio/química , Cicloexenos/química , Teoria da Densidade Funcional , Compostos de Lítio/química , Óxidos/química , Conformação Molecular , Estereoisomerismo
12.
Artigo em Inglês | MEDLINE | ID: mdl-31535952

RESUMO

In this study, we propose an improved analytical method for the multiresidue analysis of captan (plus its metabolite, tetrahydrophthalimide), folpet (plus its metabolite, phthalimide), captafol, and iprodione in cereals using liquid chromatography tandem mass spectrometry (LC-MS/MS). As captan, captafol, and folpet are easily degraded during homogenisation and extraction, samples were comminuted with liquid nitrogen, and both QuEChERS and ethyl acetate-based extraction workflows provided a satisfactory method performance. The optimised LC-MS/MS procedure with electrospray ionisation did not degrade these compounds, and offered sufficient method selectivity by resolving and minimising co-eluting matrix-derived interferences. The method also resolved the problem of non-specific mass spectra that these compounds usually produce on GC-MS analysis involving electron ionisation. The method performance was satisfactory for all 6 compounds at 0.01 mg kg-1 and higher levels of fortification, and validated as per the SANTE/11813/2017 guidelines of analytical quality control in a wide range of cereals including rice, wheat, sorghum, and corn. The method provides special advantage of simultaneous analysis of captan, and folpet along with their metabolites (tetrahydrophthalimide, and phthalimide, respectively) in combination with captafol, and iprodione in a single chromatographic run. Although iprodione is known to degrade to 3,5-dichloroaniline, since this metabolite is not a part of the residue definition, it was not included in the scope of this method. As the method demonstrates satisfactory selectivity, sensitivity, accuracy, precision, and robustness in a wide range of cereal matrices, it is recommended for regulatory testing of these compounds in cereals.


Assuntos
Aminoimidazol Carboxamida/análogos & derivados , Captana/análogos & derivados , Captana/análise , Cicloexenos/análise , Contaminação de Alimentos/análise , Hidantoínas/análise , Resíduos de Praguicidas/análise , Ftalimidas/análise , Aminoimidazol Carboxamida/análise , Cromatografia Líquida , Grão Comestível/química , Análise de Alimentos , Espectrometria de Massas em Tandem
13.
Microb Cell Fact ; 18(1): 160, 2019 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-31547812

RESUMO

BACKGROUND: Alpha-Terpineol (α-Terpineol), a C10 monoterpenoid alcohol, is widely used in the cosmetic and pharmaceutical industries. Construction Saccharomyces cerevisiae cell factories for producing monoterpenes offers a promising means to substitute chemical synthesis or phytoextraction. RESULTS: α-Terpineol was produced by expressing the truncated α-Terpineol synthase (tVvTS) from Vitis vinifera in S. cerevisiae. The α-Terpineol titer was increased to 0.83 mg/L with overexpression of the rate-limiting genes tHMG1, IDI1 and ERG20F96W-N127W. A GSGSGSGSGS linker was applied to fuse ERG20F96W-N127W with tVvTS, and expressing the fusion protein increased the α-Terpineol production by 2.87-fold to 2.39 mg/L when compared with the parental strain. In addition, we found that farnesyl diphosphate (FPP) accumulation by down-regulation of ERG9 expression and deletion of LPP1 and DPP1 did not improve α-Terpineol production. Therefore, ERG9 was overexpressed and the α-Terpineol titer was further increased to 3.32 mg/L. The best α-Terpineol producing strain LCB08 was then used for batch and fed-batch fermentation in a 5 L bioreactor, and the production of α-Terpineol was ultimately improved to 21.88 mg/L. CONCLUSIONS: An efficient α-Terpineol production cell factory was constructed by engineering the S. cerevisiae mevalonate pathway, and the metabolic engineering strategies could also be applied to produce other valuable monoterpene compounds in yeast.


Assuntos
Cicloexenos/metabolismo , Engenharia Metabólica , Monoterpenos/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Monoterpenos Cicloexânicos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fosfatos de Poli-Isoprenil/metabolismo , Sesquiterpenos/metabolismo , Vitis/enzimologia , Vitis/genética
14.
Environ Toxicol Pharmacol ; 72: 103264, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31550595

RESUMO

Vinylcyclohexene (VCH) is an environmental contaminant well known for its ovotoxicant effects in several organisms. However, the mechanisms underlying the toxicity of VCH as well as its harmful effects toward other organs are until unclear. In this work, we assess some endpoint signals of toxicity induced by volatilized VCH exposure using nymphs of the lobster cockroach Nauphoeta cinerea. Nymphs were exposed to VCH via inhalation for 70 days. The levels of volatilized VCH were quantified by headspace gas chromatography and the concentration varied between 3.41 and 7.03 nmol/µl. VCH inhalation caused a reduction of 35% in the survival rate of the exposed animals. Nymphs exposed to volatilized VCH for 35 and 70 days had a reduction in the body weight gain of 1.8- and 2.6-fold, respectively with a reduction in dissected head, fat body, and maturing reproductive organs. The exposure did not change water consumption, excepting on the 20th day (with a 3-fold change) and decreased the food intake significantly. Regarding biochemical markers, we found that the activity of GST from the dissected organs was increased by volatilized VCH after both 35 and 70 days of exposure. The fat body presented the most prominent GST activity especially after 35 days of exposure with 1.6-fold higher than the control group. Exposure also caused an increase in RS levels in the fat body of 1.35-fold and 1.47-fold after 35 and 70 days, respectively and did not affect the activity of the AChE from the head. Our findings support the harmful impact of volatilized VCH inhalation, highlighting the cockroach N.cinerea as a valuable insect model to investigate environmental toxicants.


Assuntos
Baratas/efeitos dos fármacos , Cicloexenos/toxicidade , Ninfa/efeitos dos fármacos , Administração por Inalação , Animais , Baratas/enzimologia , Corpo Adiposo/efeitos dos fármacos , Corpo Adiposo/enzimologia , Glutationa Transferase/metabolismo , Ninfa/enzimologia , Volatilização
15.
Int J Biol Macromol ; 141: 585-595, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31505208

RESUMO

Self-assembly of α-synuclein (α-Syn) is linked with a variety of neurodegenerative diseases collectively called as α-synucleiopathies. Therefore, discovering suitable inhibitors for this self-association process of α-Syn is a subject of intense research. In this background, we have demonstrated here that the natural compound, Safranal, delays/inhibits α-Syn fibrillation/aggregation, and we have also characterized its mode of action. The α-Syn fibrillation/aggregation kinetics studies in combination with TEM studies demonstrated that Safranal effectively inhibits α-Syn fibrillation/aggregation. NMR studies revealed that Safranal binds with α-Syn and stabilizes the monomeric protein. ANS fluorescence and CD measurements indicated that Safranal binds to the hydrophobic residues of the protein and causes delay in the formation of ß-sheet rich structures which are crucial for the fibrillation to occur. The results obtained from fluorescence quenching, NMR and ANS binding assays, when analysed taking into consideration the molecular structure of Safranal provide valuable insights into the mechanism of inhibition of α-Syn fibrillation/aggregation. We infer that inhibition of α-Syn fibrillation/aggregation is primarily driven by hydrophobic interactions between Safranal and the protein. Further, Safranal is also seen to dis-aggregates pre-formed α-Syn fibrils. These findings implicate that Safranal could become a potent therapeutic intervention in Parkinson's disease and other protein aggregation related disorders.


Assuntos
Cicloexenos/farmacologia , Agregados Proteicos/efeitos dos fármacos , Terpenos/farmacologia , alfa-Sinucleína/química , Cicloexenos/metabolismo , Relação Dose-Resposta a Droga , Interações Hidrofóbicas e Hidrofílicas , Estrutura Secundária de Proteína/efeitos dos fármacos , Solubilidade , Terpenos/metabolismo , alfa-Sinucleína/metabolismo
16.
Biol Pharm Bull ; 42(9): 1471-1481, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474708

RESUMO

Sutaehwan (STH) has been used in Korean medicine for the treatment of abortus habitualis such as fetal restlessness in the uterus. Previously, we reported that a modified formulation of STH, Sutaehwan-Gami, has phytoestrogen-like properties in an ovariectomized menopausal rat model. However, the therapeutic effects of STH and the precise mechanisms by which STH affects various menopausal symptoms remain poorly understood. The current study was designed to explore the effects of a modified form of STH on menopausal anxiety, depression and heart hypertrophy and its mechanisms in 4-vinylcyclohexene diepoxide (VCD)-induced menopausal mouse models. VCD-induced menopausal model mice were fed a modified form of STH, which contained water extract of 3 herbs (called STH_KP17001) at a dose of 100 or 300 mg/kg/d or as a positive control, estradiol at a dose of 0.2 mg/kg/d with standard mouse pellets for 13 weeks. The results show that STH_KP17001 significantly restored the VCD-induced weight reduction of uterine and ovary through the phosphorylation of extracellular signal-regulated kinase (ERK) and protein kinase B (AKT) in the uterus and ovary. Moreover, STH_KP17001 showed slight proliferative effects and estrogen receptor α phosphorylation in MCF-7 cells. Treatment with STH_KP17001 reversed VCD-induced anxiety and depression through AMP-activated protein kinase (AMPK) activation and brain-derived neurotrophic factor (BDNF) expression in the cerebral cortex, while improving heart hypertrophy through inactivation of inhibitor of kappaB α (IκBα) in the heart. The results indicate that STH_KP17001 improves menopause-induced anxiety, depression and heart hypertrophy, implying its protective role for the management of menopausal symptoms.


Assuntos
Ansiedade/prevenção & controle , Cardiomegalia/prevenção & controle , Depressão/prevenção & controle , Menopausa/psicologia , Extratos Vegetais/farmacologia , Animais , Cicloexenos , Modelos Animais de Doenças , Feminino , Humanos , Células MCF-7 , Medicina Tradicional Coreana , Camundongos Endogâmicos C57BL , Extratos Vegetais/isolamento & purificação , Compostos de Vinila
17.
Food Chem ; 301: 125216, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31404804

RESUMO

An improved liquid chromatography tandem mass spectrometry method is reported for the determination of residues of captan (+tetrahydrophthalimide), captafol, folpet (+phthalimide), and iprodione in fruits and vegetables. The optimized electrospray ionization parameters (high cone gas flow, and a low desolvation temperature) did not result in degradation of target compounds, rather they provided a significant advantage over the conventional GC-MS/MS methods, which lack sensitivity and repeatability. Strategies for minimizing losses in recovery of these compounds during sample preparation included cryogenic comminution, extraction with acidified ethyl acetate or acetonitrile, and dilution of the final extract with acidified water prior to LC-MS/MS analysis. The method performance complied with the SANTE/11813/2017 guidelines, with recoveries in the range of 70-120% at the LOQ of 0.01 mg/kg across the tested matrices at various pHs. The efficiency of the method was reflected in its precision (RSDs < 10%) for incurred residues.


Assuntos
Cromatografia Líquida/métodos , Contaminação de Alimentos/análise , Frutas/química , Resíduos de Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Verduras/química , Aminoimidazol Carboxamida/análogos & derivados , Aminoimidazol Carboxamida/análise , Captana/análogos & derivados , Captana/análise , Cicloexenos/análise , Hidantoínas/análise , Limite de Detecção , Ftalimidas/análise
18.
Metab Brain Dis ; 34(6): 1747-1759, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31422512

RESUMO

Alzheimer's disease (AD) is the most prevalent neurodegenerative amyloid disorder with progressive deterioration of cognitive and memory skills. Despite many efforts, no decisive therapy yet exists for AD. Safranal is the active constituent of saffron essential oil with antioxidant, anti-inflammatory, and anti-apoptotic properties. In this study, the possible beneficial effect of safranal on cognitive deficits was evaluated in a rat model of AD induced by intrahippocampal amyloid beta (Aß1-40). Safranal was daily given p.o. (0.025, 0.1, and 0.2 ml/kg) post-surgery for 1 week and finally learning and memory were evaluated in addition to assessment of the involvement of oxidative stress, inflammation, and apoptosis. Findings showed that safranal treatment of amyloid ß-microinjected rats dose-dependently improved cognition in Y-maze, novel-object discrimination, passive avoidance, and 8-arm radial arm maze tasks. Besides, safranal attenuated hippocampal level of malondialdehyde (MDA), reactive oxygen species (ROS), protein carbonyl, interleukin 1ß (IL-1ß), interleukin 6 (IL-6), tumor necrosis factor α (TNFα), nuclear factor-kappa B (NF-kB), apoptotic biomarkers including caspase 3 and DNA fragmentation, glial fibrillary acidic protein (GFAP), myeloperoxidase (MPO), and acetylcholinesterase (AChE) activity and improved superoxide dismutase (SOD) activity and mitochondrial membrane potential (MMP) with no significant effect on nitrite, catalase activity, and glutathione (GSH). Furthermore, safranal prevented CA1 neuronal loss due to amyloid ß1-40. In summary, safranal treatment of intrahippocampal amyloid beta1-40-microinjected rats could prevent learning and memory decline via neuronal protection and at a molecular level through amelioration of apoptosis, oxidative stress, inflammation, cholinesterase activity, neutrophil infiltration, and also by preservation of mitochondrial integrity.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Transtornos Cognitivos/tratamento farmacológico , Cicloexenos/uso terapêutico , Hipocampo/efeitos dos fármacos , Aprendizagem em Labirinto/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Terpenos/uso terapêutico , Doença de Alzheimer/complicações , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides , Animais , Apoptose/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/metabolismo , Cicloexenos/farmacologia , Fragmentação do DNA/efeitos dos fármacos , Modelos Animais de Doenças , Hipocampo/metabolismo , Inflamação/metabolismo , Masculino , Malondialdeído/metabolismo , Fragmentos de Peptídeos , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Terpenos/farmacologia
20.
Pestic Biochem Physiol ; 158: 185-200, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31378356

RESUMO

The present work describes the antimicrobial action of 25 monoterpenes (six hydrocarbons, five ketones, two aldehydes, six alcohols and six acetate analogues) against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus and antifungal activity against Aspergillus flavus. The antibacterial activity was evaluated by broth microdilution technique as a minimum inhibitory concentration (MIC) and the antifungal activity was performed by mycelia radial growth technique as the effective concentration causing 50% inhibition of the mycelial growth (EC50). The results showed that thymol and α-terpineol were the most potent against E. coli (MIC = 45 and 55 mg/L, respectively) and S. aureus (MIC = 135 and 225 mg/L, respectively). The results also showed that thymol displayed the maximum antifungal action against A. flavus with EC50 20 mg/L. Furthermore, the antioxidant activity was determined using N,N-dimethyl-1,4-phenylenediamine (DMPD) and the results showed that geraniol were the most potent compound (IC50 = 19 mg/L). Molecular docking studies indicated that the compounds displayed different binding interactions with the amino acid residues at the catalytic sites of N5-carboxyaminoimidazole synthetase and oxysterol binding protein Osh4 enzymes. Non-covalent interactions including van der Waals, hydrogen bonding as well as hydrophobic were observed between the compounds and the enzymes. A significant relationship was found between the docking score and the biological activity of the tested monoterpenes compared to the ceftriaxone and carbendazim as standard bactericide and fungicide, respectively. In silico ADMET properties were also performed and displayed potential for the development of promising antimicrobial agents. For these reasons, these compounds may be considered as potential ecofriendly alternatives in food preservation to delay or prevent the microbial infection and prolong the shelf life of food products.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Monoterpenos/metabolismo , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/química , Monoterpenos Cicloexânicos , Cicloexenos/química , Cicloexenos/farmacologia , Escherichia coli/efeitos dos fármacos , Hidrocarbonetos/química , Hidrocarbonetos/farmacologia , Testes de Sensibilidade Microbiana , Monoterpenos/química , Monoterpenos/farmacologia , Staphylococcus aureus/efeitos dos fármacos
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