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1.
Cell ; 174(6): 1549-1558.e14, 2018 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-30100189

RESUMEN

Engineering microorganisms for production of fuels and chemicals often requires major re-programming of metabolism to ensure high flux toward the product of interest. This is challenging, as millions of years of evolution have resulted in establishment of tight regulation of metabolism for optimal growth in the organism's natural habitat. Here, we show through metabolic engineering that it is possible to alter the metabolism of Saccharomyces cerevisiae from traditional ethanol fermentation to a pure lipogenesis metabolism, resulting in high-level production of free fatty acids. Through metabolic engineering and process design, we altered subcellular metabolic trafficking, fine-tuned NADPH and ATP supply, and decreased carbon flux to biomass, enabling production of 33.4 g/L extracellular free fatty acids. We further demonstrate that lipogenesis metabolism can replace ethanol fermentation by deletion of pyruvate decarboxylase enzymes followed by adaptive laboratory evolution. Genome sequencing of evolved strains showed that pyruvate kinase mutations were essential for this phenotype.


Asunto(s)
Ácidos Grasos no Esterificados/biosíntesis , Ingeniería Metabólica , Saccharomyces cerevisiae/metabolismo , Acetilcoenzima A/metabolismo , Glucosa/metabolismo , Glucólisis , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Lipogénesis , NADP/metabolismo , Vía de Pentosa Fosfato/genética , Piruvato Quinasa/genética , Piruvato Quinasa/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
2.
Metab Eng ; 79: 192-202, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37611820

RESUMEN

(2S)-Naringenin is a key precursor for biosynthesis of various high-value flavonoids and possesses a variety of nutritional and pharmaceutical properties on human health. Systematic optimization approaches have been employed to improve (2S)-naringenin production in different microbial hosts. However, very few studies have focused on the spatiotemporal distribution of (2S)-naringenin and the related pathway intermediate p-coumaric acid, which is an important factor for efficient production. Here, we first optimized the (2S)-naringenin biosynthetic pathway by alleviating the bottleneck downstream of p-coumaric acid and increasing malonyl-CoA supply, which improved (2S)-naringenin production but significant accumulation of p-coumaric acid still existed extracellularly. We thus established a dual dynamic control system through combining a malonyl-CoA biosensor regulator and an RNAi strategy, to autonomously control the synthesis of p-coumaric acid with the supply of malonyl-CoA. Furthermore, screening potential transporters led to identification of Pdr12 for improved (2S)-naringenin production and reduced accumulation of p-coumaric acid. Finally, a titer of 2.05 g/L (2S)-naringenin with negligible accumulation of p-coumaric acid was achieved in a fed batch fermentation. Our work highlights the importance of systematic control of pathway intermediates for efficient microbial production of plant natural products.


Asunto(s)
Flavanonas , Saccharomyces cerevisiae , Humanos , Ácidos Cumáricos , Malonil Coenzima A/genética
3.
Nat Chem Biol ; 16(2): 197-205, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31844304

RESUMEN

Phospholipids, the most abundant membrane lipid components, are crucial in maintaining membrane structures and homeostasis for biofunctions. As a structurally diverse and tightly regulated system involved in multiple organelles, phospholipid metabolism is complicated to manipulate. Thus, repurposing phospholipids for lipid-derived chemical production remains unexplored. Herein, we develop a Saccharomyces cerevisiae platform for de novo production of oleoylethanolamide, a phospholipid derivative with promising pharmacological applications in ameliorating lipid dysfunction and neurobehavioral symptoms. Through deregulation of phospholipid metabolism, screening of biosynthetic enzymes, engineering of subcellular trafficking and process optimization, we could produce oleoylethanolamide at a titer of 8,115.7 µg l-1 and a yield on glucose of 405.8 µg g-1. Our work provides a proof-of-concept study for systemically repurposing phospholipid metabolism for conversion towards value-added biological chemicals, and this multi-faceted framework may shed light on tailoring phospholipid metabolism in other microbial hosts.


Asunto(s)
Endocannabinoides/biosíntesis , Ingeniería Metabólica/métodos , Ácidos Oléicos/biosíntesis , Fosfolípidos/metabolismo , Saccharomyces cerevisiae/metabolismo , Acilcoenzima A/genética , CDPdiacilglicerol-Serina O-Fosfatidiltransferasa/genética , CDPdiacilglicerol-Serina O-Fosfatidiltransferasa/metabolismo , Coenzima A Ligasas/genética , Endocannabinoides/genética , Enzimas/genética , Enzimas/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulación Fúngica de la Expresión Génica , Glucosa/metabolismo , Lisofosfolipasa/genética , Lisofosfolipasa/metabolismo , Microorganismos Modificados Genéticamente , Monoacilglicerol Lipasas/genética , Monoacilglicerol Lipasas/metabolismo , Ácidos Oléicos/genética , Proteínas Periplasmáticas/genética , Proteínas Periplasmáticas/metabolismo , Fosfolípidos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
4.
Proc Natl Acad Sci U S A ; 116(19): 9324-9332, 2019 05 07.
Artículo en Inglés | MEDLINE | ID: mdl-31000602

RESUMEN

The cellular machinery that supports protein synthesis and secretion lies at the foundation of cell factory-centered protein production. Due to the complexity of such cellular machinery, the challenge in generating a superior cell factory is to fully exploit the production potential by finding beneficial targets for optimized strains, which ideally could be used for improved secretion of other proteins. We focused on an approach in the yeast Saccharomyces cerevisiae that allows for attenuation of gene expression, using RNAi combined with high-throughput microfluidic single-cell screening for cells with improved protein secretion. Using direct experimental validation or enrichment analysis-assisted characterization of systematically introduced RNAi perturbations, we could identify targets that improve protein secretion. We found that genes with functions in cellular metabolism (YDC1, AAD4, ADE8, and SDH1), protein modification and degradation (VPS73, KTR2, CNL1, and SSA1), and cell cycle (CDC39), can all impact recombinant protein production when expressed at differentially down-regulated levels. By establishing a workflow that incorporates Cas9-mediated recombineering, we demonstrated how we could tune the expression of the identified gene targets for further improved protein production for specific proteins. Our findings offer a high throughput and semirational platform design, which will improve not only the production of a desired protein but even more importantly, shed additional light on connections between protein production and other cellular processes.


Asunto(s)
Interferencia de ARN , Proteínas Recombinantes/biosíntesis , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Genoma Fúngico , Microfluídica , Proteínas Recombinantes/genética , Recombinación Genética , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo
5.
Nanotechnology ; 32(25)2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33725670

RESUMEN

Detection of cell-free DNA (cfDNA) has an impact on DNA analysis in liquid biopsies. However, current strategies to detect cfDNA have limitations that should be overcome, such as having low sensitivity and requiring much time and a specialized instrument. Thus, non-invasive and rapid detection tools are needed for disease prevention and early-stage treatment. Here we developed a device having a microheater integrated with zinc oxide nanowires (microheater-ZnO-NWs) to detect target single-stranded DNAs (ssDNAs) based on DNA probe hybridization. We confirmed experimentally that our device realizedin-situannealed DNA probes by which we subsequently detected target ssDNAs. We envision that this device can be utilized for fundamental studies related to nanobiodevice-based DNA detection.


Asunto(s)
Técnicas Biosensibles , Ácidos Nucleicos Libres de Células/análisis , ADN de Cadena Simple/análisis , Dispositivos Laboratorio en un Chip , Nanocables/química , Óxido de Zinc/química , Sondas de ADN/química , Humanos , Límite de Detección , Biopsia Líquida/métodos , Hibridación de Ácido Nucleico/métodos
6.
Pharm Biol ; 59(1): 565-574, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33989107

RESUMEN

CONTEXT: The petroleum ether extract (PET) of Amygdalus mongolica (Maxim.) Ricker (Rosaceae) has an ameliorative effect on renal fibrosis (RF). OBJECTIVE: To evaluate the antifibrotic effects of A. mongolica seeds PET on RF by serum metabolomics, biochemical and histopathological analyses. MATERIALS AND METHODS: Sixty male Sprague-Dawley rats were randomly divided into the sham-operated, RF model, benazepril hydrochloride-treated model (1.5 mg/kg) and PET-treated (1.75, 1.25, 0.75 g/kg) groups, and the respective drugs were administered intragastrically for 21 days. Biochemical indicators including BUN, Scr, HYP, SOD, and MDA were measured. Haematoxylin and eosin and Masson staining were used for histological examination. The serum metabolomic profiles were determined by UPLC-Q-TOF/MS and metabolism network analysis. Acute toxicity test was performed to validate biosafety. RESULTS: The PET LD50 was >23.9 g/kg in rats. PET significantly alleviated fibrosis by reducing the levels of Scr (from 34.02 to 32.02), HYP (from 403.67 to 303.17) and MDA (from 1.84 to 1.73), and increasing that of SOD (from 256.42 to 271.85). Metabolomic profiling identified 10 potential biomarkers, of which three key markers were significantly associated with RF-related pathways including phenylalanine, tyrosine and tryptophan biosynthesis, amino sugar and nucleotide sugar metabolism and tyrosine metabolism. In addition, three key biomarkers were restored to baseline levels following PET treatment, with the medium dose showing optimal effect. CONCLUSIONS: These findings revealed the mechanism of A. mongolica PET antifibrotic effects for RF rats on metabolic activity and provided the experimental basis for the clinical application.


Asunto(s)
Alcanos , Antifibróticos/uso terapéutico , Enfermedades Renales/tratamiento farmacológico , Metabolómica/métodos , Extractos Vegetales/uso terapéutico , Rosaceae , Animales , Antifibróticos/aislamiento & purificación , Fibrosis , Enfermedades Renales/metabolismo , Enfermedades Renales/patología , Masculino , Extractos Vegetales/aislamiento & purificación , Ratas , Ratas Sprague-Dawley
7.
Biotechnol Lett ; 42(3): 453-460, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31863218

RESUMEN

OBJECTIVE: To determine the effect of large genomic region deletion in a Saccharomyces cerevisiae strain on tyrosine yield and to identify new genetic modification targets through transcriptome analysis. RESULTS: TAL was used to produce p-coumaric acid (p-CA) from tyrosine to quantity tyrosine yield. S. cerevisiae mutant strain NK14 with deletion of a 23.8 kb genomic region was identified to have p-CA production of 10.3 mg L- 1, while the wild-type strain BY4741 had p-CA production of 1.06 mg L- 1. Analysis of growth patterns and stress tolerance showed that the deletion did not affect the growth phenotype of NK14. Transcriptome analysis suggested that, compared to BY4741, genes related to glycolysis (ENO2, TKL1) and the tyrosine pathway (ARO1, ARO2, ARO4, ARO7, TYR1) were upregulated in NK14 at different levels. Besides genes related to the tyrosine biosynthetic pathway, amino acid transporters (AVT6, VBA5, THI72) and transcription factor (ARO80) also showed changes in transcription levels. CONCLUSIONS: We developed a strain with improved tyrosine yield and identified new genetic modification candidates for tyrosine production.


Asunto(s)
Perfilación de la Expresión Génica , Regulación Fúngica de la Expresión Génica , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Eliminación de Secuencia , Transcriptoma , Tirosina/biosíntesis , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/biosíntesis , Proteínas de Saccharomyces cerevisiae/genética , Tirosina/genética
8.
Xenobiotica ; 49(2): 216-226, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29325475

RESUMEN

1. To investigate Genkwa Flos hepatotoxicity, a cell metabolomics strategy combined with serum pharmacology was performed on human HL-7702 liver cells in this study. 2. Firstly, cell viability and biochemical indicators were determined and the cell morphology was observed to confirm the cell injury and develop a cell hepatotoxicity model. Then, with the help of cell metabolomics based on UPLC-MS, the Genkwa Flos group samples were completely separated from the blank group samples in the score plots and seven upregulated as well as two down-regulated putative biomarkers in the loading plot were identified and confirmed. Besides, two signal molecules and four enzymes involved in biosynthesis pathway of lysophosphatidylcholine and the sphingosine kinase/sphingosine-1-phosphate pathway were determined to investigate the relationship between Genkwa Flos hepatotoxicity and these two classic pathways. Finally, the metabolic pathways related to specific biomarkers and two classic metabolic pathways were analyzed to explain the possible mechanism of Genkwa Flos hepatotoxicity. 3. Based on the results, lipid peroxidation and oxidative stress, phospholipase A2/lysophosphatidylcholine pathway, the disturbance of sphingosine-1-phosphate metabolic profile centered on sphingosine kinase/sphingosine-1-phosphate pathway and fatty acid metabolism might be critical participators in the progression of liver injury induced by Genkwa Flos.


Asunto(s)
Medicamentos Herbarios Chinos/toxicidad , Hígado/efectos de los fármacos , Animales , Células Cultivadas , Daphne/química , Medicamentos Herbarios Chinos/efectos adversos , Humanos , Hígado/metabolismo , Masculino , Redes y Vías Metabólicas , Metabolómica , Estrés Oxidativo , Ratas Sprague-Dawley , Organismos Libres de Patógenos Específicos
9.
Pharm Biol ; 57(1): 694-700, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31608748

RESUMEN

Context: Terrestrosin D (TED), from Tribulus terrestris L. (Zygophyllaceae), exhibits anti-tumour and anti-inflammatory activities. However, its effects on bleomycin (BLM)-induced pulmonary inflammation and the subsequent fibrotic changes remain unclear. Objective: To examine the anti-inflammatory and anti-fibrotic effects of TED against BLM in murine pulmonary tissues. Materials and methods: Male SPF mice received saline (control), TED (10 mg/kg), BLM (2.5 mg/kg), or BLM (2.5 mg/kg) + TED (10 mg/kg) group. BLM was administered as a single intranasal inoculation, and TED was intraperitoneally administered once daily. After 2 and 6 weeks of treatment, cell number and differentiation (Giemsa staining) and TNF-α, IL-6, IL-8, TGF-ß1, and PDGF-AB levels (ELISA) were determined in the bronchoalveolar lavage fluid (BALF). Hydroxyproline (Hyp) content in the left pulmonary tissue was also determined (ELISA). The right pulmonary tissue was H&E-stained and assessed for the severity of pulmonary fibrosis using the Ashcroft scoring method. Compared with the BLM group, TED decreased inflammatory cell infiltration; number of macrophages (p < 0.05), neutrophils (p < 0.05), lymphocytes (p < 0.05); percentage of macrophages in the monocyte-macrophage system (p < 0.05), and levels of TNF-α (p < 0.01), IL-6 (p < 0.01), IL-8 (p < 0.05), TGF-ß1 (p < 0.05), and PDGF-AB (p < 0.05) in the BALF. TED also reduced Hyp content (p < 0.05) in the pulmonary tissue and attenuated the BLM-induced deterioration in lung histopathology. Discussion and conclusions: TED can inhibit BLM-induced inflammation and fibrosis in the lungs of mice, which may be related to reduced inflammatory and fibrotic markers. These results could be further tested in humans through clinical studies.


Asunto(s)
Antiinflamatorios/farmacología , Inflamación/tratamiento farmacológico , Fibrosis Pulmonar/tratamiento farmacológico , Saponinas/farmacología , Tribulus/química , Animales , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/uso terapéutico , Bleomicina , Líquido del Lavado Bronquioalveolar , Modelos Animales de Enfermedad , Inflamación/patología , Masculino , Ratones , Fibrosis Pulmonar/patología , Saponinas/aislamiento & purificación , Saponinas/uso terapéutico
10.
FEMS Yeast Res ; 18(8)2018 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-30107496

RESUMEN

As a traditional ethanol-producing microorganism, Saccharomyces cerevisiae is an ideal host for consolidated bioprocessing. However, expression of heterologous cellulase increases the metabolic burden in yeast, which results in low cellulase activity and poor cellulose degradation efficiency. In this study, cellulase-expressing yeast strains that could efficiently degrade different cellulosic substrates were created by optimizing cellulase ratios through a POT1-mediated δ-integration strategy. Metabolic engineering strategies, including optimization of codon usage, promoter and signal peptide, were also included in this system. We also confirmed that heterologous cellulase expression in cellulosic yeast induced the unfolded protein response. To enhance protein folding capacity, the endoplasmic reticulum chaperone protein BiP and the disulfide isomerase Pdi1p were overexpressed, and the Golgi membrane protein Ca2+/Mn2+ ATPase Pmr1p was disrupted to decrease the glycosylation of cellulase. The resultant strain, SK18-3, could produce 5.4 g L-1 ethanol with carboxymethyl-cellulose. Strain SK12-50 achieved 4.7 g L-1 ethanol production with phosphoric acid swollen cellulose hydrolysis. When Avicel was used as the substrate, 3.8 g L-1 ethanol (75% of the theoretical maximum yield) was produced in SK13-34. This work will significantly increase our knowledge of how to engineer optimal yeast strains for biofuel production from cellulosic biomass.


Asunto(s)
Celulasa/genética , Celulasa/metabolismo , Celulosa/metabolismo , Etanol/metabolismo , Ingeniería Metabólica/métodos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Codón , Expresión Génica , Regiones Promotoras Genéticas , Señales de Clasificación de Proteína , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
11.
Environ Monit Assess ; 190(7): 388, 2018 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-29886560

RESUMEN

Heavy metal accumulation and potential releases from loose deposits in drinking water distribution system (DWDS) can have critical impacts on drinking water safety, but the associated risks have not been sufficiently evaluated. In this work, the potential biological toxicity of heavy metals in loose deposits was calculated based on consensus-based sediment quality guidelines, and the effects of some of the main water quality parameters, such as the pH and bicarbonate and phosphate content, on the release behaviors of pre-accumulated heavy metals were investigated. The results showed that heavy metals (Cu, As, Cr, Pb, and Cd) significantly accumulated in all the samples, but the contents of the heavy metals were multiple magnitudes lower than the Fe and Mn contents. The potential biotoxicity of As and Cu was relatively high, but the biotoxicity of Cd was negligible. The water quality can significantly influence the release of heavy metals from loose deposits. As the pH increased from 7.0 to 9.0, the release of As and Cr obviously increased. The release of As, Cu, Pb, and Cr also accelerated with the addition of phosphate (from 1 to 5 mg/L). In contrast to the trends for the pH and phosphate, variations in the bicarbonate content did not have a significant influence on the release of As and Cr. The release ratios of heavy metals in the samples were very low, and there was not a correlation between the release rate of the heavy metals in the loose deposits and their potential biotoxicity.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis , China , Agua Potable/química , Sedimentos Geológicos/química , Calidad del Agua
12.
FEMS Yeast Res ; 17(6)2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-28922845

RESUMEN

In biotechnological industry, increased expression cassette stability and copy number serve as important means of maintaining consistently high production levels of heterologous proteins in Saccharomyces cerevisiae. In this study, we combined δ sequences for site-specific integration with TPI1 gene from Schizosaccharomyces pombe (POT1) as a selection marker to realize high-copy integration and stable expression of heterologous proteins in S. cerevisiae. With the newly developed POT1 platform, a 32-copy integration of enhanced green fluorescent protein (EGFP) expression cassette was obtained in a single round and was stably maintained after 100 generations of growth in a rich complex medium. Talaromyces emersonii cellobiohydrolase I gene was synthesized with S. cerevisiae codon bias and expressed under the control of TPI1 promoter and terminator via POT1-mediated δ-integration; the highest specific activity yielded 238 mU g-1 of dry cell weight when p-nitrophenyl-ß-D-cellobioside was used as substrate, whereas the highest activity in cellulose hydrolysis reached 67% Avicel conversion. POT1-mediated δ-integration produces high protein levels over a wide dynamic range and enables broad applications in metabolic engineering and synthetic biology.


Asunto(s)
Dosificación de Gen , Expresión Génica , Regiones Promotoras Genéticas , Proteínas Recombinantes/genética , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Celulosa 1,4-beta-Celobiosidasa/análisis , Celulosa 1,4-beta-Celobiosidasa/genética , Eurotiales/enzimología , Eurotiales/genética , Genes Reporteros , Inestabilidad Genómica , Proteínas Fluorescentes Verdes/análisis , Proteínas Fluorescentes Verdes/genética , Proteínas Recombinantes/biosíntesis , Recombinación Genética , Schizosaccharomyces/enzimología , Schizosaccharomyces/genética
13.
J Toxicol Environ Health A ; 80(22): 1212-1221, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28910587

RESUMEN

Trichosanthin (TCS), isolated from the root tuber of Trichosantheskirilowii, a well-known traditional Chinese medicinal plant, belonging to the Cucurbitaceae family, was found to exhibit numerous biological and pharmacological activities including anti-inflammatory. However, the effects of TCS on arterial injury induced neointimal hyperplasia and inflammatory cell infiltration remains poorly understood. The aim of study was to examine the effectiveness of TCS on arterial injury-mediated inflammatory processes and underlying mechanisms. A balloon-injured carotid artery induced injury in vivo in rats was established as a model of vascular injury. After 1 day TCS at 20, 40, or 80 mg/kg/day was administered intraperitoneally, daily for 14 days. Subsequently, the carotid artery was excised and taken for immunohistochemical staining. Data showed that TCS significantly dose-dependently reduced balloon injury-induced neointima formation in the carotid artery model rat, accompanied by markedly decreased positive expression percentage proliferating cell nuclear antigen (PCNA). In the in vitro study vascular smooth muscle cells (VSMC) were cultured, proliferation stimulated with platelet-derived growth factor-BB (PDGF-BB) (20 ng/ml) and TCS at 1, 2, or 4 µM added. Data demonstrated that TCS inhibited proliferation and cell cycle progression of VSMC induced by PDGF-BB. Further, TCS significantly lowered mRNA expression of cyclinD1, cyclinE1, and c-fos, and protein expression levels of Akt1, Akt2, and mitogen-activated protein kinase MAPK (ERK1) signaling pathway mediated by PDGF-BB. These findings indicate that TCS inhibits vascular neointimal hyperplasia induced by vascular injury in rats by suppression of VSMC proliferation and migration, which may involve inhibition of Akt/MAPK/ERK signal pathway.


Asunto(s)
Hiperplasia/tratamiento farmacológico , Neointima/tratamiento farmacológico , Tricosantina/farmacología , Tricosantina/uso terapéutico , Lesiones del Sistema Vascular/tratamiento farmacológico , Animales , Antiinflamatorios/farmacología , Antiinflamatorios/uso terapéutico , Catéteres/efectos adversos , Hiperplasia/etiología , Masculino , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Lesiones del Sistema Vascular/etiología
14.
J Toxicol Environ Health A ; 80(22): 1193-1198, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28949828

RESUMEN

The seeds of Amygdalus mongolica contain various constituents including flavonoids and vitamin E, which are known to exert antioxidant effects. However, the safety of the oil extract of this compound is not fully known. The aim of this study was to determine the physicochemical properties of A. mongolica oil, identify the constituents and subsequently assess the effectiveness of utilizing this seed extract in hyperlipidemia as an antioxidant agent. In particular, the toxicity and safety of A. mongolica oil were examined with emphasis on effects on blood lipids level and serum lipid peroxidation using a hyperlipidemia rat model. Treatment with 20 ml/kg A. mongolica oil produced no apparent adverse effects after 14 days in normal female and male rats. A dose of 2.5-10 ml/kg A. mongolica oil administered to hyperlipidemic male rats significantly decreased serum total cholesterol (TC), low-density lipoprotein-C (LDL-C), malondialdehyde (MDA), total cholesterol high-density lipoprotein-C (TC/HDL-C), LDL-C/HDL-C, and atherosclerosis index(AI). In contrast, glutathione (GSH) levels and activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were significantly increased. Data demonstrated that A. mongolica oil may be utilized in conditions of hyperlipidemia due to its antioxidant effects.


Asunto(s)
Hiperlipidemias/tratamiento farmacológico , Aceites de Plantas/química , Aceites de Plantas/farmacología , Prunus/química , Ratas , Animales , Antioxidantes/química , Antioxidantes/farmacología , Activación Enzimática/efectos de los fármacos , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Peroxidación de Lípido/efectos de los fármacos , Lípidos/sangre , Masculino , Oxidorreductasas/genética , Oxidorreductasas/metabolismo , Distribución Aleatoria , Ratas Wistar
15.
Biotechnol Lett ; 39(7): 977-982, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28299546

RESUMEN

OBJECTIVE: To identify new enzymatic bottlenecks of L-tyrosine pathway for further improving the production of L-tyrosine and its derivatives. RESULT: When ARO4 and ARO7 were deregulated by their feedback resistant derivatives in the host strains, the ARO2 and TYR1 genes, coding for chorismate synthase and prephenate dehydrogenase were further identified as new important rate-limiting steps. The yield of p-coumaric acid in the feedback-resistant strain overexpressing ARO2 or TYR1, was significantly increased from 6.4 to 16.2 and 15.3 mg l-1, respectively. Subsequently, we improved the strain by combinatorial engineering of pathway genes increasing the yield of p-coumaric acid by 12.5-fold (from 1.7 to 21.3 mg l-1) compared with the wild-type strain. Batch cultivations revealed that p-coumaric acid production was correlated with cell growth, and the formation of by-product acetate of the best producer NK-M6 increased to 31.1 mM whereas only 19.1 mM acetate was accumulated by the wild-type strain. CONCLUSION: Combinatorial metabolic engineering provides a new strategy for further improvement of L-tyrosine or other metabolic biosynthesis pathways in S. cerevisiae.


Asunto(s)
Antiinfecciosos/metabolismo , Liasas de Fósforo-Oxígeno/metabolismo , Prefenato Deshidrogenasa/metabolismo , Propionatos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Tirosina/metabolismo , Ácidos Cumáricos , Expresión Génica , Ingeniería Metabólica , Redes y Vías Metabólicas/genética , Liasas de Fósforo-Oxígeno/genética , Prefenato Deshidrogenasa/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
16.
Analyst ; 140(19): 6736-41, 2015 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-26332096

RESUMEN

Research towards nucleic acid amplification technologies for detection of human papillomavirus (HPV) 16 E6/E7 mRNA was carried out in combination with microchip electrophoresis (MCE). The approaches of nucleic acid sequence based amplification (NASBA), one-step RT-PCR and two-step RT-PCR were successfully developed. NASBA was a simple enzymatic reaction, which directly amplified HPV16 mRNA by isothermal amplification, leaving out the complex and tedious operation. One-step RT-PCR simplified the amplification step, while two-step RT-PCR was more sensitive and less vulnerable to the interference. Furthermore, instead of gel electrophoresis, microchip electrophoresis (MCE) for RNA assay was employed to realize high-throughput and rapid analysis. Finally, the results show that PCR-based or NASBA-based mRNA tests are valuable for HPV mRNA assay, which can be potentially applied for clinical diagnosis and prognosis of cervical and other anogenital carcinoma.


Asunto(s)
Electroforesis por Microchip/métodos , Técnicas de Amplificación de Ácido Nucleico/métodos , Proteínas Oncogénicas Virales/genética , Proteínas E7 de Papillomavirus/genética , Proteínas Represoras/genética , Tampones (Química) , ARN Mensajero/análisis , ARN Mensajero/genética , ARN Mensajero/aislamiento & purificación
17.
Sci Total Environ ; 923: 171312, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38423319

RESUMEN

The persistent and increasing levels of sulfate due to a variety of human activities over the last decades present a widely concerning environmental issue. Understanding the controlling factors of groundwater sulfate and predicting sulfate concentration is critical for governments or managers to provide information on groundwater protection. In this study, the integration of self-organizing map (SOM) approach and machine learning (ML) modeling offers the potential to determine the factors and predict sulfate concentrations in the Huaibei Plain, where groundwater is enriched with sulfate and the areas have complex hydrogeological conditions. The SOM calculation was used to illustrate groundwater hydrochemistry and analyze the correlations among the hydrochemical parameters. Three ML algorithms including random forest (RF), support vector machine (SVM), and back propagation neural network (BPNN) were adopted to predict sulfate levels in groundwater by using 501 groundwater samples and 8 predictor variables. The prediction performance was evaluated through statistical metrics (R2, MSE and MAE). Mine drainage mainly facilitated increase in groundwater SO42- while gypsum dissolution and pyrite oxidation were found another two potential sources. The major water chemistry type was Ca-HCO3. The dominant cation was Na+ while the dominant anion was HCO3-. There was an intuitive correlation between groundwater sulfate and total dissolved solids (TDS), Cl-, and Na+. By using input variables identified by the SOM method, the evaluation results of ML algorithms showed that the R2, MSE and MAE of RF, SVM, BPNN were 0.43-0.70, 0.16-0.49 and 0.25-0.44. Overall, BPNN showed the best prediction performance and had higher R2 values and lower error indices. TDS and Na+ had a high contribution to the prediction accuracy. These findings are crucial for developing groundwater protection and remediation policies, enabling more sustainable management.

18.
Artículo en Inglés | MEDLINE | ID: mdl-38598659

RESUMEN

Based on a specific zinc storage mechanism and excellent electronic conductivity, transition metal dichalcogenides, represented by vanadium diselenide, are widely used in aqueous zinc-ion battery (AZIB) energy storage systems. However, most vanadium diselenide cathode materials are presently limited by low specific capacity and poor cycling life. Herein, a simple hydrothermal process has been proposed for obtaining a vanadium diselenide cathode for an AZIB. The interaction of defects and crystal planes enhances zinc storage capacity and reduces the migration energy barrier. Moreover, abundant lamellar structure greatly increases reaction sites and alleviates volume expansion during the electrochemical process. Thus, the as-obtained vanadium diselenide AZIB exhibits an excellent reversible specific capacity of 377 mAh g-1 at 1 A g-1, and ultralong cycle stability of 291 mAh g-1 after 3200 cycles, with a nearly negligible capacity loss. This one-stone-for-two-birds strategy would be expected to be applied to large-scale synthesis of a high-performance zinc-ion battery cathode in the future.

19.
Sensors (Basel) ; 13(5): 5406-47, 2013 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-23615581

RESUMEN

The technology of sensor, pervasive computing, and intelligent information processing is widely used in Body Sensor Networks (BSNs), which are a branch of wireless sensor networks (WSNs). BSNs are playing an increasingly important role in the fields of medical treatment, social welfare and sports, and are changing the way humans use computers. Existing surveys have placed emphasis on the concept and architecture of BSNs, signal acquisition, context-aware sensing, and system technology, while this paper will focus on sensor, data fusion, and network communication. And we will introduce the research status of BSNs, the analysis of hotspots, and future development trends, the discussion of major challenges and technical problems facing currently. The typical research projects and practical application of BSNs are introduced as well. BSNs are progressing along the direction of multi-technology integration and intelligence. Although there are still many problems, the future of BSNs is fundamentally promising, profoundly changing the human-machine relationships and improving the quality of people's lives.


Asunto(s)
Redes de Comunicación de Computadores/instrumentación , Cuerpo Humano , Tecnología Inalámbrica/instrumentación , Humanos , Sistemas Hombre-Máquina
20.
J Cosmet Dermatol ; 22(3): 1108-1123, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36465034

RESUMEN

OBJECTIVE: Long-term and high exposure to UV radiation can lead to the development of skin photoaging diseases. Therefore, there is an ongoing need for more natural and safe drugs to prevent or treat skin photoaging diseases. METHODS: The Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform database were used to collect the active compounds and corresponding targets of Cnidii Fructus, Arnebiae Radix, Angelicae Sinensis Radix, Poria, and Borneolum. The GeneCards database and the NCBI Gene database were used to collect the targets of skin photoaging diseases. The STRING database was used to construct a protein-protein interaction network formed by the intersecting targets of drugs and diseases. The Metascape database was applied for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis of the targets. Molecular docking between active compounds and targets was verified by Autodock. After that, the skin photoaging model of mice was established and treated with MP gel. The skin characterization on the back of mice was observed, and the ameliorative effect of MP gel on skin photoaging was evaluated by histological and epidermal thickness assays. The MDA content and SOD activity were measured. Caspase-3 expression in mouse skin tissues was detected by immunohistochemistry, quantitative real-time polymerase chain reaction assay, and Western blot. RESULTS: The results of network pharmacology experiments showed that the natural drugs have multi-component, multi-target therapeutic disease characteristics. The results of animal studies showed that MP gel improved the health of photoaged skin, promoted skin structural integrity, had antioxidant properties and significantly inhibited caspase-3 expression. CONCLUSION: The experimental validation of the results of the preliminary network pharmacology analysis was carried out in animal experiments, which confirmed part of the mechanism of action of MP gel in the prevention and treatment of skin photoaging.


Asunto(s)
Envejecimiento de la Piel , Animales , Ratones , Simulación del Acoplamiento Molecular , Caspasa 3 , Farmacología en Red , Piel
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