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1.
Arch Biochem Biophys ; 747: 109738, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37696383

RESUMO

Acute kidney injury in sepsis patients has an extreme mortality rate in clinical. It obviously seems that immune cells, for example, macrophages are involved with this process. Macrophages, as highly important immune cells, play a significant role in the development of human kidney diseases. But the specific role of macrophages in this process is still unclear. Under different timeline points, we surprisingly found that macrophages had the most dynamic changes in acute kidney injury immune cells. Based on macrophages' functions, they are primarily classified into M1 macrophages (pro-inflammatory) and M2 macrophages (anti-inflammatory). The polarization of M2 macrophages is closely associated with the seriousness of sepsis-induced kidney injury, but how to modulate their polarization to alleviate sepsis-associated renal damage remains unknown. We discovered that the polarization of M2 macrophages after methylprednisolone injection can significantly alleviate acute kidney injury by reducing secreted cytokine. This study suggests that the proportion of macrophage subtypes can be regulated by methylprednisolone to alleviate acute kidney injury in sepsis to provide a new sight for a clinical to provide a promising strategy for renal injury caused.


Assuntos
Injúria Renal Aguda , Sepse , Humanos , Metilprednisolona/farmacologia , Metilprednisolona/uso terapêutico , Rim , Macrófagos , Injúria Renal Aguda/tratamento farmacológico , Sepse/complicações , Sepse/tratamento farmacológico
2.
Biotechnol Appl Biochem ; 70(6): 1806-1816, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37278163

RESUMO

Rhamnolipid, as a low-toxic, biodegradable and environmentally friendly biosurfactant, has broad application prospects in many industries. However, the quantitative determination of rhamnolipid is still a challenging task. Here, a new sensitive method for the quantitative analysis of rhamnolipid based on a simple derivatization reaction was developed. In this study, 3-[3'-(l-rhamnopyranosyloxy) decanoyloxy] decanoic acid (Rha-C10-C10) and 3-[3'-(2'-O-α-l-rhamnopyranosyloxy) decanoyloxy] decanoic acid (Rha-Rha-C10-C10) were utilized as the representative rhamnolipids. Liquid chromatography-mass spectrometry and high-performance liquid chromatography-ultra violet results showed that these two compounds were successfully labeled with 1 N1-(4-nitrophenyl)-1,2-ethylenediamine. There was an excellent linear relationship between rhamnolipid concentration and peak area of labeled rhamnolipid. The detection limits of the Rha-C10-C10 and Rha-Rha-C10-C10 were 0.018 mg/L (36 nmol/L) and 0.014 mg/L (22 nmol/L), respectively. The established amidation method was suitable for the accurate analysis of rhamnolipids in the biotechnological process. The method had good reproducibility with the relative standard deviation of 0.96% and 0.79%, respectively, and sufficient accuracy with a recovery of 96%-100%. This method was applied to quantitative analysis of 10 rhamnolipid homologs metabolized by Pseudomonas aeruginosa LJ-8. The single labeling method was used for the quantitative analysis of multiple components, which provided an effective method for the quality evaluation of other glycolipids with carboxyl groups.


Assuntos
Biotecnologia , Glicolipídeos , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes , Glicolipídeos/metabolismo , Pseudomonas aeruginosa , Tensoativos/química
3.
Biotechnol Appl Biochem ; 70(1): 238-248, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35419893

RESUMO

Surfactin, which is composed of a ß-hydroxy fatty acid chain and a peptide ring, has drawn considerable attention due to its potential applications in the biomedicine, bioremediation, and petroleum industries. However, the low yield of surfactin from wild strains still restricts its industrial applications. In this study, eight genes relevant to the fatty acid biosynthesis pathway were targeted to enhance surfactin production, and high surfactin-yielding strains with potential industrial applications were obtained. When ldeHA and acc were co-overexpressed, the surfactin yield of recombinant strains TDS8 and TPS8 increased to 1.55- and 1.19-fold of their parental strains, respectively, again proving that the conversion of acetyl-coenzyme A (CoA) to malonyl-CoA is the rate-limiting step in fatty acid biosynthesis. Furthermore, changes in surfactin isoforms of recombinant strain TPS8 suggest that the fatty acid precursor synthesis pathway can be modified to improve the proportion of different isoforms. In addition, the deletion of lpdV, which is responsible for the conversion of α-ketoacyl-CoA precursors, resulted in a sharp decrease in surfactin production, further demonstrating the importance of branched-chain fatty acid biosynthesis in surfactin production. This work will facilitate the design and construction of more efficiently engineered strains for surfactin production and further extend industrial applications.


Assuntos
Bacillus subtilis , Ácidos Graxos , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Ácidos Graxos/metabolismo , Engenharia Genética , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Lipopeptídeos/genética , Lipopeptídeos/metabolismo , Peptídeos Cíclicos/genética , Peptídeos Cíclicos/metabolismo
4.
J Integr Neurosci ; 22(2): 48, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36992603

RESUMO

BACKGROUND: Neuroinflammation triggered by chronic cerebral ischemia-induced microglial pyroptosis is a significant contributor to vascular cognitive impairment. It has been shown that emodin possesses anti-inflammatory and neuroprotective properties, however, it's potential molecular and signaling transduction pathway remains to be illuminated. This study researched the neuroprotective mechanisms of emodin focussing on emodin effects on lipopolysaccharide/adenosine triphosphate (LPS/ATP)-caused pyroptosis in BV2 cells and HT-22 hippocampal neurons. METHODS: To explore the neuroprotective effect of emodin, Emodin was applied to BV2 cells, HT-22 hippocampal neurons, and BV2/HT-22 co-cultures stimulated with LPS/ATP to evaluate the cell morphology, levels of inflammatory factors, NLRP3 inflammatory inflammasome activity and focal pyroptosis-related protein expression, as same as neuronal apoptosis. RESULTS: Emodin alleviated LPS/ATP-induced pyroptosis of BV2 cells by preventing the activity of the NLRP3 inflammasome and the cleavage of pyroptosis executive protein Gasdermin D (GSDMD). Furthermore, levels of interleukin (IL)-18, IL-1ß and tumor necrosis factor (TNF)-α were reduced, the apoptosis of HT-22 hippocampal neurons was attenuated, and cell viability was restored. CONCLUSIONS: Emodin can antagonize microglial neurotoxicity by inhibiting microglial pyroptosis, thereby exerting anti-inflammatory and neuroprotective effects.


Assuntos
Emodina , Fármacos Neuroprotetores , Trifosfato de Adenosina/metabolismo , Anti-Inflamatórios/farmacologia , Emodina/farmacologia , Inflamassomos/metabolismo , Lipopolissacarídeos , Microglia , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Piroptose , Linhagem Celular , Animais , Camundongos
5.
Environ Microbiol ; 24(7): 3063-3080, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35254697

RESUMO

The recently proposed order Candidatus Thermoprofundales, currently containing only one family-level lineage Marine Benthic Group-D (MBG-D), is distributed in global subsurface ecosystems and ecologically important, but its diversity, evolution and metabolism remain largely unknown. Here we described two novel family-level specialized lineages in Ca. Thermoprofundales, JdFR-43 and HyVt, which are restricted to specific biotopes (primarily in marine hydrothermal vents and occasionally in oil reservoirs and hot springs) in contrast to the cosmopolitan lineage MBG-D. The comparative genomics revealed that the specialized lineages have streamlined genomes, higher GC contents, enriched genes associated with nucleotide biosynthesis, ribosome biogenesis and DNA repair and additional thermostable aminopeptidases, enabling them to adapt to high-temperature habitats such as marine hydrothermal vents, deep subsurface oil reservoirs and hot springs. On the contrary, the unique metabolic traits of the cosmopolitan MBG-D, motility, glycolysis, butanoate metabolism, secondary metabolites production and additional genes for specific peptides and carbohydrates degradation potentially enhance its response to environmental change. Substrate preference is found for most MAGs across all lineages with the ability to utilize both polysaccharides (chitin and starch) and proteinaceous substances, whereas JdFR-43 members from oil reservoirs can only utilize proteins. These results expand the diversity of Ca. Thermoprofundales significantly and further improve our understandings of the adaptations of Ca. Thermoprofundales to various environments.


Assuntos
Fontes Termais , Fontes Hidrotermais , Archaea/genética , Ecossistema , Filogenia
6.
Eur Heart J ; 42(36): 3770-3782, 2021 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-34179969

RESUMO

AIMS: Despite considerable therapeutic advances, there is still a dearth of evidence on the molecular determinants of cardiac hypertrophy that culminate in heart failure. Neuraminidases are a family of enzymes that catalyze the cleavage of terminal sialic acids from glycoproteins or glycolipids. This study sought to characterize the role of neuraminidases in pathological cardiac hypertrophy and identify pharmacological inhibitors targeting mammalian neuraminidases. METHODS AND RESULTS: Neuraminidase 1 (NEU1) was highly expressed in hypertrophic hearts of mice and rats, and this elevation was confirmed in patients with hypertrophic cardiomyopathy (n = 7) compared with healthy controls (n = 7). The increased NEU1 was mainly localized in cardiomyocytes by co-localization with cardiac troponin T. Cardiomyocyte-specific NEU1 deficiency alleviated hypertrophic phenotypes in response to transverse aortic constriction or isoproterenol hydrochloride infusion, while NEU1 overexpression exacerbated the development of cardiac hypertrophy. Mechanistically, co-immunoprecipitation coupled with mass spectrometry, chromatin immunoprecipitation, and luciferase assays demonstrated that NEU1 translocated into the nucleus and interacted with GATA4, leading to Foetal gene (Nppa and Nppb) expression. Virtual screening and experimental validation identified a novel compound C-09 from millions of compounds that showed favourable binding affinity to human NEU1 (KD = 0.38 µM) and effectively prevented the development of cardiac remodelling in cellular and animal models. Interestingly, anti-influenza drugs zanamivir and oseltamivir effectively inhibited mammalian NEU1 and showed new indications of cardio-protection. CONCLUSIONS: This work identifies NEU1 as a critical driver of cardiac hypertrophy and inhibition of NEU1 opens up an entirely new field of treatment for cardiovascular diseases.


Assuntos
Cardiomiopatia Hipertrófica , Insuficiência Cardíaca , Animais , Cardiomegalia , Humanos , Camundongos , Miócitos Cardíacos , Neuraminidase , Ratos
7.
Zhongguo Zhong Yao Za Zhi ; 47(2): 499-510, 2022 Jan.
Artigo em Zh | MEDLINE | ID: mdl-35178995

RESUMO

Under the guidance of the traditional Chinese medicine(TCM) theory of "Zangfu-organs of spleen and stomach" and the modern theory of "microbiota-gut-brain axis", this study explored the effects of Nardostachys jatamansi on the gut microbiota of rats with Parkinson's disease(PD). The 40 SD rats were randomly divided into the control group, PD model group, levodopa group, and Nardostachys jatamansi ethanol extract group. The PD model was established by subcutaneous injection of rotenone in the neck and back area. After 14 days of intragastric administration, the PD rats' behaviors were analyzed through open field test, inclined plane test, and pole test. After the behavioral tests, the striatum, colon, and colon contents of rats in each group were collected. Western blot was employed to detect the protein expression of tyrosine hydroxylase(TH) and α-synuclein(α-syn) in striatum and that of α-syn in colon. Enzyme linked immunosorbent assay(ELISA) was used to detect the levels of tumor necrosis factor-α(TNF-α), interleukin-1ß(IL-1ß), and nuclear factor-kappa B(NF-κB) in striatum and colon. High-throughput sequencing of 16 S rRNA gene was conducted to detect the differences in microbial diversity, abundance, differential phyla, and dominant bacteria of rats between groups. The results indicated that Nar. ethanol extract could relieve dyskinesia, reverse the increased levels of α-syn, TNF-α, IL-1ß, and NF-κB in striatum, and improve the protein expression of TH in striatum of PD rats. The α diversity analysis indicated a significant decrease in diversity and abundance of gut microbiota in the PD model. The results of linear discriminant analysis effect size(LEfSe) of dominant bacteria indicated that Nardostachys jatamansi ethanol extract increased the relative abundance of Clotridiaceae, Lachnospiraceae, and Anaerostipes, and reversed the increased relative abundance of Proteobacteria, Gammaproteobacteria, Enterobacteriaceae, and Escherichia-Shigella in PD model group to exhibit the neuroprotective effect. In summary, the results indicated that Nar. ethanol extract exert the therapeutic effect on PD rats. Specifically, the extract may regulate gut microbiota, decrease the levels of proinflammatory cytokines, and reduce the protein aggregation of α-syn in the colon and striatum to alleviate intestinal inflammation and neuroinflammation. This study provides a basis for combining the theory of "Zangfu-organs of spleen and stomach" with the theory of "microbiota-gut-brain axis" to treat PD.


Assuntos
Microbioma Gastrointestinal , Nardostachys , Doença de Parkinson , Animais , NF-kappa B/metabolismo , Nardostachys/genética , Nardostachys/metabolismo , Doença de Parkinson/tratamento farmacológico , Ratos , Ratos Sprague-Dawley
8.
Zhongguo Zhong Yao Za Zhi ; 46(16): 4157-4166, 2021 Aug.
Artigo em Zh | MEDLINE | ID: mdl-34467728

RESUMO

This article aims to establish the fingerprints, determine the hemostatic pharmacodynamic indicators, and explore the spectrum-effect relationship of Notoginseng Radix et Rhizoma in 12 different specifications. Firstly, HPLC and liquid chromatography-mass spectrometry(LC-MS) were employed to establish the fingerprints of Notoginseng Radix et Rhizoma. The rat plasma recalcification experiment and the rat gastric bleeding experiment were conducted to determine the pharmacodynamic indicators, including plasma recalcification time(PRT), thrombin time(TT), prothrombin time(PT), and activated partial thromboplastin time(APTT). Afterwards, the partial least squares method was employed to explore the spectrum-effect relationship of Notoginseng Radix et Rhizoma in different specifications. Twenty-six common peaks were detected in the HPLC fingerprints of different specifications of Notoginseng Radix et Rhizoma, and 11 out of the 26 common peaks represented saponins. The content of dencichine was determined by LC-MS. The rat experiments showed that the pharmacodynamic indicators were significantly different among different specifications of Notoginseng Radix et Rhizoma. The spectrum-effect relationship was explored between 27 common components and pharmacodynamic indicators. Among them, 16 components had positive effects on the pharmacodynamic indicators of Notoginseng Radix et Rhizoma, and 11 exerted negative effects. This study provides a basis for the precision medication and quality control of Notoginseng Radix et Rhizoma.


Assuntos
Medicamentos de Ervas Chinesas , Hemostáticos , Saponinas , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/farmacologia , Controle de Qualidade , Ratos , Rizoma
9.
Anal Biochem ; 600: 113746, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32333904

RESUMO

Metabolite profiling in anaerobic alkane biodegradation plays an important role in revealing activation mechanisms. Apart from alkylsuccinates, which are considered to be the usual biomarkers via fumarate addition, the downstream metabolites of C-skeleton rearrangement can also be regarded as biomarkers. However, it is difficult to detect intermediate metabolites in both environmental samples and enrichment cultures, resulting in lacking direct evidence to prove the occurrence of fumarate addition pathway. In this work, a synthetic method of rearrangement metabolites was established. Four compounds, namely, propylmalonic acid, 2-(2-methylbutyl)malonic acid, 2-(2-methylpentyl)malonic acid and 2-(2-methyloctyl)malonic acid, were synthesized and determined by four derivatization approaches. Besides, their mass spectra were obtained. Four characteristic ions were observed at m/z 133 + 14n, 160 + 28n, 173 + 28n and [M - (45 + 14n)]+ (n = 0 and 2 for ethyl and n-butyl esters, respectively). For methyl esterification, mass spectral features were m/z 132, 145 and [M - 31]+, while for silylation, fragments were m/z 73, 147, 217, 248, 261 and [M - 15]+. These data provide basis on identification of potential rearrangement metabolites in anaerobic alkane biodegradation via fumarate addition.


Assuntos
Alcanos/metabolismo , Fumaratos/metabolismo , Malonatos/metabolismo , Alcanos/química , Anaerobiose , Fumaratos/química , Malonatos/química , Espectrometria de Massas
10.
Environ Sci Technol ; 54(17): 10610-10620, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32786606

RESUMO

Microbial anaerobic alkane degradation is a key process in subsurface oil reservoirs and anoxic environments contaminated with petroleum, with a major impact on global carbon cycling. However, the thermophiles capable of water-insoluble paraffins (>C17) degradation under methanogenic conditions has remained understudied. Here, we established thermophilic (55 °C) n-paraffins-degrading (C21-C30) cultures from an oil reservoir. After over 900 days of incubation, the even-numbered n-paraffins were biodegraded to methane. The bacterial communities are dominated by a novel class-level lineage of actinobacteria, 'Candidatus Syntraliphaticia'. These 'Ca. Syntraliphaticia'-like metagenome-assembled genomes (MAGs) encode a complete alkylsuccinate synthases (ASS) gene operon, as well as hydrogenases and formate dehydrogenase, and several enzymes potentially involved in alkyl-CoA oxidation and the Wood-Ljungdahl pathway. Metatranscriptomic analysis suggests that n-paraffins are activated via fumarate addition reaction, and oxidized into carbon dioxide, hydrogen/formate and acetate by 'Ca. Syntraliphaticia', that could be further converted to methane by the abundant hydrogenotrophic and acetoclastic methanogens. We also found a divergent methyl-CoM reductase-like complex (MCR) and a canonical MCR in two MAGs representing 'Ca. Methanosuratus' (within candidate phylum Verstraetearchaeota), indicating the capability of methane and short-chain alkane metabolism in the oil reservoir. Ultimately, this result offers new insights into the degradability and the mechanisms of n-paraffins under methanogenic conditions at high temperatures.


Assuntos
Euryarchaeota , Parafina , Alcanos , Anaerobiose , Metano , Filogenia
11.
Angew Chem Int Ed Engl ; 59(48): 21578-21584, 2020 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-32767734

RESUMO

Derivatives based on anthryleno[1,2-b]pyrazine-2,3-dicarbonitrile (DCPA) are used as luminescent materials, to realize near-infrared (NIR) electroluminescence. By functionalizing DCPA with aromatic amine donors, two emitters named DCPA-TPA and DCPA-BBPA are designed and synthesized. Both molecules have large dipole moments owing to the strong intramolecular charge transfer interactions between the amine donors and the DCPA acceptor. Thus, compared with doped films, the emission of neat films of DCPA-TPA and DCPA-BBPA can fully fall into the NIR region (>700 nm) with increasing surrounding polarity by increasing doping ratio. Moreover, the non-doped devices based on DCPA-TPA and DCPA-BBPA provide NIR emission with peaks at 838 and 916 nm, respectively. A maximum radiance of 20707 mW Sr-1 m-2 was realized for the further optimized device based on DCPA-TPA. This work provides a simple and efficient strategy of molecular design for developing NIR emitting materials.

12.
Circulation ; 137(13): 1374-1390, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29212895

RESUMO

BACKGROUND: As new biomarkers of coronary artery diseases (CAD) emerge via metabolomics, the underlying functional mechanisms remain to be elucidated. Functional metabolomics aims to translate metabolomics-derived biomarkers to disease mechanisms. METHODS: A cohort of 2324 patients who underwent coronary angiography from 4 independent centers was studied. A combination of ultra-performance liquid chromatography and quadrupole time-of-flight mass spectrometry in the negative ion mode was used for untargeted analysis of metabolites in plasma. Significant differential metabolites were identified by cross-comparisons with and within CAD types, including normal coronary artery, nonobstructvie coronary atherosclerosis, stable angina, unstable angina, and acute myocardial infarction. A tandem liquid chromatography-mass spectrometry-based approach using isotope-labeled standard addition was subsequently performed for targeted analysis of the metabolic marker N-acetylneuraminic acid (Neu5Ac). A functional metabolomics strategy was proposed to investigate the role of Neu5Ac in the progression of CAD by using in vitro and in vivo models. RESULTS: We identified a total of 36 differential metabolites, 35 of which were confirmed with reference compounds. Elevation of Neu5Ac was observed in plasma during CAD progression in center 1 (P=4.0e-64, n=2019) and replicated in 3 independent centers (n=305). The increased level of Neu5Ac in plasma was confirmed by accurate targeted quantification. Mechanistically, Neu5Ac was able to trigger myocardial injury in vitro and in vivo by activation of the Rho/Rho-associated coiled-coil containing protein kinase signaling pathway through binding to RhoA and Cdc42, but not Rac1. Silencing neuraminidase-1, the enzyme that regulates Neu5Ac generation, ameliorated oxygen-glucose deprivation-induced injury in cardiomyocytes and ligation/isoprenaline-induced myocardial ischemia injury in rats. Pharmacological inhibition of neuraminidase by anti-influenza drugs, oseltamivir and zanamivir, also protected cardiomyocytes and the heart from myocardial injury. CONCLUSIONS: Functional metabolomics identified a key role for Neu5Ac in acute myocardial infarction, and targeting neuraminidase-1 may represent an unrecognized therapeutic intervention for CAD.


Assuntos
Doença da Artéria Coronariana/patologia , Metabolômica , Ácido N-Acetilneuramínico/sangue , Animais , Biomarcadores/sangue , Biomarcadores/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Angiografia Coronária , Doença da Artéria Coronariana/metabolismo , Humanos , Masculino , Miócitos Cardíacos/citologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Neuraminidase/antagonistas & inibidores , Neuraminidase/genética , Neuraminidase/metabolismo , Oseltamivir/farmacologia , Ligação Proteica , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína cdc42 de Ligação ao GTP/metabolismo , Proteína rhoA de Ligação ao GTP/metabolismo
13.
Appl Environ Microbiol ; 85(16)2019 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-31175186

RESUMO

Methanogenic degradation of n-alkanes is prevalent in n-alkane-impacted anoxic oil reservoirs and oil-polluted sites. However, little is known about the initial activation mechanism of the substrate, especially n-alkanes with a chain length above C16 Here, a methanogenic C16 to C20n-alkane-degrading enrichment culture was established from production water of a low-temperature oil reservoir. At the end of the incubation (364 days), C16 to C20 (1-methylalkyl)succinates were detected in the n-alkane-amended enrichment culture, suggesting that fumarate addition had occurred in the degradation process. This evidence is supported further by the positive amplification of the assA gene encoding the alpha subunit of alkylsuccinate synthase. A phylogenetic analysis shows these assA amplicons to be affiliated with Smithella and Desulfatibacillum clades. Together with the high abundance of these clades in the bacterial community, these two species are postulated to be the key players in the degradation of C16 to C20n-alkanes in the present study. Our results provide evidence that long n-alkanes are activated via a fumarate addition mechanism under methanogenic conditions.IMPORTANCE Methanogenic hydrocarbon degradation is the major process for oil degradation in subsurface oil reservoirs and is blamed for the formation of heavy oil and oil sands. Addition of n-alkanes to fumarate yielding alkyl-substituted succinates is a well-characterized anaerobic activation mechanism for hydrocarbons and is the most common activation mechanism in the anaerobic biodegradation of n-alkanes with chain lengths less than C16 However, the activation mechanism involved in the methanogenic biodegradation of n-alkanes longer than C16 is still uncertain. In this study, we analyzed a methanogenic enrichment culture amended with a mixture of C16 to C20n-alkanes. These n-alkanes can be activated via fumarate addition by mixed cultures containing Smithella and Desulfatibacillum species under methanogenic conditions. These observations provide a fundamental understanding of long-n-alkane metabolism under methanogenic conditions and have important applications for the remediation of oil-contaminated sites and for energy recovery from oil reservoirs.


Assuntos
Alcanos/metabolismo , Deltaproteobacteria/metabolismo , Fumaratos/metabolismo , Metano/metabolismo , Alcanos/química , Archaea/classificação , Archaea/genética , Archaea/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Crescimento Quimioautotrófico , Deltaproteobacteria/classificação , Deltaproteobacteria/genética , Filogenia
14.
Appl Microbiol Biotechnol ; 103(5): 2391-2401, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30610291

RESUMO

Branched alkanes are important constituents of crude oil and are usually regarded as resistant to microbial degradation, resulting in little knowledge of biochemical processes involved in anaerobic branched alkanes biodegradation. Here, we initiated an incubation study by amendment of iso-C9 (2-methyl, 3-methyl, and 4-methyloctane) as substrates for methanogenic degradation in production water from a high-temperature petroleum reservoir. Over an incubation period of 367 days, significant methanogenesis was observed in samples amended with these branched alkanes. The strong methanogenic activity only observed in iso-C9 amendments suggested the presence of microbial transformation from iso-alkanes into methane. GC-MS-based examination of the original production water identified an intermediate tentatively to be iso-C9-like alkylsuccinate, but was not detected in the enrichment cultures, combined with the successful amplification of assA functional gene in inoculating samples, revealing the ability of anaerobic biodegradation of iso-C9 via fumarate addition pathway. Microorganisms affiliated with members of the Firmicutes, Synergistetes, and methanogens of genus Methanothermobacter spp. were highly enriched in samples amended with iso-C9. The co-occurrence of known syntrophic acetate oxidizers Thermoacetogenium spp. and Methanothermobacter spp. (known hydrogenotrophic methanogens) indicates a potential syntrophic acetate oxidation associated with the methanogenic biodegradation of iso-C9. These results provide some useful information on the potential biodegradation of branched alkanes via methanogenesis and also suggest that branched alkanes are likely activated via fumarate addition in high-temperature petroleum reservoirs.


Assuntos
Alcanos/metabolismo , Biodegradação Ambiental , Firmicutes/metabolismo , Metano/biossíntese , Methanobacteriaceae/metabolismo , Petróleo/metabolismo , Crescimento Quimioautotrófico , Temperatura Alta , Campos de Petróleo e Gás , Água/química
15.
Med Sci Monit ; 25: 2966-2975, 2019 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-31009445

RESUMO

BACKGROUND This study aimed to investigate the association of single nucleotide polymorphisms (SNPs) of Forkhead box O3 (FOXO3) gene with type 2 diabetes mellitus (T2D). MATERIAL AND METHODS A total of 843 elderly residents from east China were enrolled in this study, which included 426 patients with type 2 diabetes and 417 controls. Four SNPs were analyzed by qPCR. Genotype frequencies of the 4 SNPs in FOXO3 of the patients and controls were analyzed using logistic regression analysis. The association between each SNP and clinical indicators was analyzed by linear regression analysis. RESULTS None of the 4 FOXO3 variants, rs13217795, rs2764264, rs2802292, and rs13220810, were associated with the risk of type 2 diabetes compared to controls. However, rs13217795, rs2764264, and rs2802292 were associated with lower blood glucose levels. Notably, further subgroup analysis indicated that the longevity-associated alleles of FOXO3 SNP (rs13217795, rs2764264, and rs2802292) were associated with lower blood glucose levels in women (TC versus TT, -0.724 mmol/L, P=0.005; CC versus TT, -1.093 mmol/L, P=0.03; TC versus TT, -0.801 mmol/L, P=0.002; CC versus TT, -1.212 mmol/L, P=0.001; TG versus TT, -0.754 mmol/L, P=0.004; and GG versus TT, -1.150 mmol/L, P=0.001) but not in men. CONCLUSIONS The results indicated that longevity-associated FOXO3 variants were correlated with lower blood glucose levels in elderly women with type 2 diabetes in east China.


Assuntos
Diabetes Mellitus Tipo 2/genética , Proteína Forkhead Box O3/genética , Longevidade/genética , Idoso , Idoso de 80 Anos ou mais , Povo Asiático/genética , Estudos de Casos e Controles , China , Feminino , Proteína Forkhead Box O3/metabolismo , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
16.
Clin Exp Hypertens ; 40(7): 695-701, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29400588

RESUMO

Essential hypertension is a leading global public health issue, billions of people suffered from it every year. Recently, multiple evidence suggests that DNA methylation play an important role in regulating blood pressure. Here, we tested the risk for essential hypertension conferred by single nucleotide polymorphisms (SNPs) within DNA methyltransferase 1 (DNMT1). Three loci (rs2228611, rs2228612, and rs16999593) were selected to be analyzed in 3410 cases and 1307 normal controls in southern Chinese aged 60 or above. No significant association with essential hypertension was observed for rs2228612 and rs16999593. A higher risk of essential hypertension was found in the minor A allele of rs2228611 in the codominant and recessive model (P < 0.05). After stratified by sex, this association was found in male but not female. Furthermore, this difference was abolished after BMI adjustment in the whole population and reduced in male. In addition, the mutation rate of rs2228611 was higher in the obesity group compared with the normal weight group of male. Intriguingly, rs2228611 was also a risk factor of essential hypertension in normal weight male. These findings indicated that rs2228611 might contribute to male hypertension via BMI-dependent mechanisms in obesity male and BMI-independent mechanisms in normal weight male.


Assuntos
DNA (Citosina-5-)-Metiltransferase 1/genética , Hipertensão Essencial/genética , Predisposição Genética para Doença/genética , Idoso , Alelos , Povo Asiático/genética , Pressão Sanguínea , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Fatores de Risco , Fatores Sexuais
17.
Biodegradation ; 29(3): 233-243, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29502248

RESUMO

The increasing usage of partially hydrolyzed polyacrylamide (HPAM) in oilfields as a flooding agent to enhance oil recovery at so large quantities is an ecological hazard to the subsurface ecosystem due to persistence and inertness. Biodegradation of HPAM is a potentially promising strategy for dealing with this problem among many other methods available. To understand the responsible microorganisms and mechanism of HPAM biodegradation under anaerobic conditions, an enrichment culture from production waters of oil reservoirs were established with HPAM as the sole source of carbon and nitrogen incubated for over 328 days, and analyzed using both molecular microbiology and chemical characterization methods. Gel permeation chromatography, High-pressure liquid chromatography and Fourier-transformed infrared spectroscopy results indicated that, after 328 days of anaerobic incubation, some of the amide groups on HPAM were removed and released as ammonia/ammonium and carboxylic groups, while the carbon backbone of HPAM was converted to smaller polymeric fragments, including oligomers and various fatty acids. Based on these results, the biochemical process of anaerobic biodegradation of HPAM was proposed. The phylogenetic analysis of 16S rRNA gene sequences retrieved from the enrichments showed that Proteobacteria and Planctomycetes were the dominant bacteria in the culture with HPAM as the source of carbon and nitrogen, respectively. For archaea, Methanofollis was more abundant in the anaerobic enrichment. These results are helpful for understanding the process of HPAM biodegradation and provide significant insights to the fate of HPAM in subsurface environment and for possible bioremediation.


Assuntos
Resinas Acrílicas/metabolismo , Metano/metabolismo , Campos de Petróleo e Gás/microbiologia , Águas Residuárias/microbiologia , Resinas Acrílicas/química , Anaerobiose/efeitos dos fármacos , Archaea/efeitos dos fármacos , Archaea/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Biodegradação Ambiental/efeitos dos fármacos , Carbono/farmacologia , Ácidos Graxos Voláteis/análise , Hidrólise , Nitrogênio/farmacologia , Filogenia , RNA Ribossômico 16S/genética
18.
Biochim Biophys Acta Mol Basis Dis ; 1863(7): 1848-1857, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28483578

RESUMO

Hepatic stellate cells (HSCs) are considered as the main effector cells in vitamin A metabolism and liver fibrosis, as well as in hepatic immune regulation. Recently, researches have revealed that HSCs have plasticity and heterogeneity, which depend on their lobular location and whether liver is normal or injured. This research aimed to explore the biological characteristics and heterogeneity of HSCs in mice with Schistosoma japonicum (S. japonicum) infection, and determine the subpopulation of HSCs in pathogenesis of hepatic fibrosis caused by S. japonicum infection. Results revealed that HSCs significantly increased the expressions of MHC II and fibrogenic genes after S. japonicum infection, and could be classified into MHC II+ HSCs and MHC II- HSCs subsets. Both two HSCs populations suppressed the proliferation of activated CD4+T cells, whereas only MHC II- HSCs displayed a myofibroblast-like phenotype. In response to IFN-γ, HSCs up-regulated the expressions of MHC II and CIITA, while down-regulated the expression of fibrogenic gene Col1. In addition, praziquantel treatment decreased the expressions of fibrogenic genes in MHC II- HSCs. These results confirmed that HSCs from S. japonicum-infected mice have heterogeneity. The MHC II- α-SMA+ HSCs were major subsets of HSCs contributing to liver fibrosis and could be considered as a potential target of praziquantel anti-fibrosis treatment.


Assuntos
Células Estreladas do Fígado/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Cirrose Hepática/imunologia , Schistosoma japonicum/imunologia , Esquistossomose Japônica/imunologia , Animais , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Feminino , Células Estreladas do Fígado/patologia , Antígenos de Histocompatibilidade Classe II/genética , Interferon gama/genética , Interferon gama/imunologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Esquistossomose Japônica/genética , Esquistossomose Japônica/patologia
19.
Appl Microbiol Biotechnol ; 101(18): 7053-7063, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28730409

RESUMO

Acetate is a key intermediate in anaerobic crude oil biodegradation and also a precursor for methanogenesis in petroleum reservoirs. The impact of iron oxides, viz. ß-FeOOH (akaganéite) and magnetite (Fe3O4), on the methanogenic acetate metabolism in production water of a high-temperature petroleum reservoir was investigated. Methane production was observed in all the treatments amended with acetate. In the microcosms amended with acetate solely about 30% of the acetate utilized was converted to methane, whereas methane production was stimulated in the presence of magnetite (Fe3O4) resulting in a 48.34% conversion to methane. Methane production in acetate-amended, ß-FeOOH (akaganéite)-supplemented microcosms was much faster and acetate consumption was greatly improved compared to the other conditions in which the stoichiometric expected amounts of methane were not produced. Microbial community analysis showed that Thermacetogenium spp. (known syntrophic acetate oxidizers) and hydrogenotrophic methanogens closely related to Methanothermobacter spp. were enriched in acetate and acetate/magnetite (Fe3O4) microcosms suggesting that methanogenic acetate metabolism was through hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers. The acetate/ß-FeOOH (akaganéite) microcosms, however, differed by the dominance of archaea closely related to the acetoclastic Methanosaeta thermophila. These observations suggest that supplementation of ß-FeOOH (akaganéite) accelerated the production of methane further, driven the alteration of the methanogenic community, and changed the pathway of acetate methanogenesis from hydrogenotrophic methanogenesis fueled by syntrophic acetate oxidizers to acetoclastic.


Assuntos
Ácido Acético/metabolismo , Euryarchaeota/metabolismo , Compostos Férricos/metabolismo , Metano/metabolismo , Petróleo/metabolismo , Biodegradação Ambiental , Óxido Ferroso-Férrico , Temperatura Alta , Oxirredução , Água
20.
J Neuroinflammation ; 13(1): 266, 2016 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-27733201

RESUMO

BACKGROUND: Immunosuppression has been described as a consequence of brain injury and infection by different mechanisms. Angiostrongylus cantonensis can cause injury to the central nervous system and eosinophilic meningitis to human. Both T cell and B cell immunity play an essential role in the resistance of the infection. However, whether brain injury caused by A. cantonensis infection can lead to immunosuppression is not clear. Therefore, the present study sought to observe the alteration of immune responses in mice infected with A. cantonensis. METHODS: Mice were infected with 20 third-stage A. cantonensis larvae. The messenger RNA (mRNA) expression of inflammatory mediators in brain tissues was observed by qRT-PCR. Cell surface markers including CD3, CD4, CD8, CD19, B220, 7-AAD, annexin-V, IgM, AA4.1, and CD23 were evaluated by using flow cytometry. The immune functions of T and B lymphocytes were detected upon stimulation by ConA and antibody responses to a nonself antigen OVA, respectively. Activation of the hypothalamic-pituitary-adrenal axis was evaluated by analyzing the concentration of plasma corticosterone and levels of mRNA for corticotropin-releasing hormone, tyrosine hydroxylase, and c-fos. RESULTS: A. cantonensis infection results in obvious immunosuppression evidenced as progressive spleen and thymus atrophy and significant decrease in the number of lymphocyte subsets including B cells, CD3+ T cells, CD4+ T cells, and CD8+ T cells, as well as reduced T cell proliferation at 21 days post-infection and antibody reaction to exogenous protein after infection. However, the sharp decrease of splenic and thymic cells was not due to cell apoptosis but to B cell genesis cessation and impairing thymocyte development. In addition, helminthicide treatment with albendazole on infected mice at 7 days post-infection could prevent immunosuppressive symptoms. Importantly, infected mice displayed hypothalamic-pituitary-adrenal axis activation, with peak responses occurring at 16 days post-infection, and glucocorticoid receptor antagonist could partially restore the infection-induced cessation of B cell genesis. CONCLUSIONS: Brain injury caused by A. cantonensis infection, like that of brain stroke and trauma, enhanced endogenous corticosteroid activity, resulting in peripheral immunosuppression.


Assuntos
Citocinas/metabolismo , Sistema Hipotálamo-Hipofisário , Terapia de Imunossupressão , Sistema Hipófise-Suprarrenal , Infecções por Strongylida/patologia , Albendazol/uso terapêutico , Angiostrongylus cantonensis/patogenicidade , Animais , Antiprotozoários/uso terapêutico , Proliferação de Células , Corticosterona/metabolismo , Citocinas/genética , Feminino , Citometria de Fluxo , Antagonistas de Hormônios/farmacologia , Sistema Hipotálamo-Hipofisário/imunologia , Sistema Hipotálamo-Hipofisário/parasitologia , Sistema Hipotálamo-Hipofisário/patologia , Pulmão/parasitologia , Pulmão/patologia , Camundongos , Camundongos Endogâmicos BALB C , Mifepristona , Ovalbumina/imunologia , Sistema Hipófise-Suprarrenal/imunologia , Sistema Hipófise-Suprarrenal/parasitologia , Sistema Hipófise-Suprarrenal/patologia , RNA Mensageiro/metabolismo , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia
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