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1.
MedComm (2020) ; 5(3): e475, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38463393

RESUMO

Senescence-associated microRNAs (SA-miRNAs) are important molecules for aging regulation. While many aging-promoting SA-miRNAs have been identified, confirmed aging-suppressive SA-miRNAs are rare, that impeded our full understanding on aging regulation. In this study, we verified that miR-708 expression is decreased in senescent cells and aged tissues and revealed that miR-708 overexpression can alleviate cellular senescence and aging performance. About the molecular cascade carrying the aging suppressive action of miR-708, we unraveled that miR-708 directly targets the 3'UTR of the disabled 2 (Dab2) gene and inhibits the expression of DAB2. Interestingly, miR-708-caused DAB2 downregulation blocks the aberrant mammalian target of rapamycin complex 1 (mTORC1) activation, a driving metabolic event for senescence progression, and restores the impaired autophagy, a downstream event of aberrant mTORC1 activation. We also found that AMP-activated protein kinase (AMPK) activation can upregulate miR-708 via the elevation of DICER expression, and miR-708 inhibitor is able to blunt the antiaging effect of AMPK. In summary, this study characterized miR-708 as an aging-suppressive SA-miRNA for the first time and uncovered a new signaling cascade, in which miR-708 links the DAB2/mTOR axis and AMPK/DICER axis together. These findings not only demonstrate the potential role of miR-708 in aging regulation, but also expand the signaling network connecting AMPK and mTORC1.

2.
J Environ Manage ; 325(Pt B): 116484, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36283172

RESUMO

Thermal pollution from stormwater runoff has been the focus of many studies in recent years due to its potential harm to aquatic microorganisms. However, there were few studies on the thermal pollution caused by stormwater runoff from various types of urban pavement surfaces. A lab-scale experiment was conducted to compare the thermal load of stormwater runoff from impermeable and permeable pavements and the influencing factors were investigated. The experimental findings demonstrated that the rainfall return period and initial temperature of various pavement surfaces significantly impacted the thermal load. The stormwater runoff absorbed more heat as the initial temperature, and rainfall return period increased. The difference of the thermal load of stormwater runoff between permeable brick pavement (PBP) and the impermeable asphalt pavement (IAP) increased from 305.26 to 436.70 kJ/m2, when the initial surface temperature rose from 35 to 47 °C. The average runoff temperature decreased by 1.39-1.90 °C for PBP compared to the IAP, with an increase in surface temperature from 35 to 47 °C. Under the various initial surface temperatures, the mean temperature of the infiltration effluent from the PBP was 3.12-4.20 °C lower than the average temperature of stormwater runoff from the surface layer. Therefore, a PBP can effectively alleviate thermal pollution from stormwater runoff and safeguard the receiving waters' quality.


Assuntos
Chuva , Movimentos da Água , Qualidade da Água , Hidrocarbonetos/análise , Monitoramento Ambiental
3.
Biochem Pharmacol ; 200: 115045, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35439535

RESUMO

Compounds with senolysis activity are discovered in recent years, featuring by their capacity to specifically eliminate senescent cells in vitro or in vivo. These compounds, referring to as Senolytics, provide a new method for aging counteraction and probably for geriatric disease amelioration. However, their clinical application is unpractical still, mainly because of the safety issue. In fact, the effective dose range even of the most potent senolytic cannot guarantee the safety requirements application for human being. Here, we report a study which investigated the combinational application of one potential senolytic molecule navitoclax, a Bcl-2 inhibitor with several mTOR inhibitors, to assess the influence of this combination on the senolytic outcome. Our results reveal that pan-mTOR inhibitors can reduce the dosage or timespan of navitoclax necessary for reaching IC50 and LT50 in senescent cells, also extend the lifespan of premature-aged Drosophila and mitigate the aging-related phenotype. Our results also confirmed that mTOR inhibitor sensitized senolytic cell death is apoptotic and pan-mTOR inhibitors PP242 and AZD8055 works more effectively than mTORC1 inhibitor Rapamycin. Mechanically, we verified the crucial role of mTORC2 inhibition contributes sensitization by increasing the expression of the pro-apoptotic protein Bim. In summary, this study firstly exposes the sensitization effect of pan-mTOR inhibitors on navitoclax-induced senolytic apoptosis, therefore providing novel evidence to show the advantage of drug combination on setting senotherapy. It also provides an intriguing clue to demonstrate the value of mTORC2 inhibition for apoptotic death of senescent cells.


Assuntos
Inibidores de MTOR , Senoterapia , Compostos de Anilina , Apoptose , Alvo Mecanístico do Complexo 2 de Rapamicina , Sulfonamidas
4.
Signal Transduct Target Ther ; 7(1): 66, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-35241643

RESUMO

Nicotinamide adenine dinucleotide (NAD+) is indispensable for the anti-aging activity of the sirtuin (SIRT) family enzymes. AMP-activated protein kinase (AMPK) upregulates NAD+ synthesis and SIRT activity in a nicotinamide phosphoribosyltransferase (NAMPT)-dependent manner. However, the molecular mechanisms that affect AMPK-driven NAMPT expression and NAD+/SIRT activation remain unclear. In this study, we tried to identify senescence-associated microRNAs (miRNAs) that negatively regulate the cascade linking AMPK and NAMPT expression. miRNA-screening experiments showed that the expression of miR-146a increased in senescent cells but decreased following AMPK activation. Additionally, miR-146a overexpression weakened the metformin-mediated upregulation of NAMPT expression, NAD+ synthesis, SIRT activity, and senescence protection, whereas treatment with the miR-146a inhibitor reversed this effect. Importantly, these findings were observed both in vitro and in vivo. Mechanistically, miR-146a directly targeted the 3'-UTR of Nampt mRNA to reduce the expression of NAMPT. AMPK activators metformin and 5-aminoimidazole-4-carboxamide (AICAR) hindered miR-146a expression at the transcriptional level by promoting IκB kinase (IKK) phosphorylation to attenuate nuclear factor-kappaB (NF-κB) activity. These findings identified a novel cascade that negatively regulates the NAD+/SIRT pathway by suppressing miR-146a-mediated NAMPT downregulation. Furthermore, our results showed that miR-146a impedes the anti-aging effect of AMPK. This mutual inhibitory relationship between miR-146a and AMPK enriches our understanding of the molecular connections between AMPK and SIRT and provides new insight into miRNA-mediated NAD+/SIRT regulation and an intervention point for the prevention of aging and age-related diseases.


Assuntos
Metformina , MicroRNAs , Sirtuínas , Regiões 3' não Traduzidas , Proteínas Quinases Ativadas por AMP/genética , Metformina/farmacologia , MicroRNAs/genética , MicroRNAs/metabolismo , NAD/metabolismo , Nicotinamida Fosforribosiltransferase/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Sirtuínas/genética
5.
Int J Mol Sci ; 22(13)2021 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-34209701

RESUMO

The present study aims to reveal the mechanism by which miR-430s regulate steroidogenesis in larval rice field eel Monopterus albus. To this end, M. albus embryos were respectively microinjected with miRNA-overexpressing mimics (agomir430a, agomir430b, and agomir430c) or miRNA-knockdown inhibitors (antagomir430a, antagomir430b, and antagomir430c). Transcriptome profiling of the larvae indicated that a total of more than 149 differentially expressed genes (DEGs) were identified among the eight treatments. Specifically, DEGs related to steroidogenesis, the GnRH signaling pathway, the erbB signaling pathway, the Wnt signaling pathway, and other pathways were characterized in the transcriptome. We found that steroidogenesis-related genes (hydroxysteroid 17-beta dehydrogenase 3 (17ß-hsdb3), hydroxysteroid 17-beta dehydrogenase 7 (17ß-hsdb7), hydroxysteroid 17-beta dehydrogenase 12 (17ß-hsdb12), and cytochrome P450 family 19 subfamily a (cyp19a1b)) were significantly downregulated in miR-430 knockdown groups. The differential expressions of miR-430 in three gonads indicated different roles of three miR-430 (a, b, and c) isoforms in regulating steroidogenesis and sex differentiation. Mutation of the miR-430 sites reversed the downregulation of cytochrome P450 family 17 (cyp17), cyp19a1b, and forkhead box L2 (foxl2) reporter activities by miR-430, indicating that miR-430 directly interacted with cyp17, cyp19a1b, and foxl2 genes to inhibit their expressions. Combining these findings, we concluded that miR-430 regulated the steroidogenesis and the biosynthesis of steroid hormones by targeting cyp19a1b in larval M. albus. Our results provide a novel insight into steroidogenesis at the early stage of fish at the molecular level.


Assuntos
Vias Biossintéticas/genética , Peixes/genética , Peixes/metabolismo , Regulação da Expressão Gênica , MicroRNAs/genética , Esteroides/biossíntese , Regiões 3' não Traduzidas , Animais , Biologia Computacional/métodos , Perfilação da Expressão Gênica , Família Multigênica , Transcriptoma
6.
Artigo em Inglês | MEDLINE | ID: mdl-32625169

RESUMO

It is widely recognized that chemical, physical, and biological factors can singly or synergistically evoke the excessive production of oxidative stress in pulmonary tissue that followed by pulmonary lesions and pneumonia. In addition, metabolic and endocrine disorder-induced diseases such as diabetes and obesity often expressed higher susceptibility to pulmonary infections, and presented severe symptoms which increasing the mortality rate. Therefore, the connection between the lesion of the lungs and the metabolic/endocrine disorders is an interesting and essential issue to be addressed. Studies have noticed a similar pathological feature in both infectious pneumonia and metabolic disease-intercurrent pulmonary lesions, that is, from the view of molecular pathology, the accumulation of excessive reactive oxygen species (ROS) in pulmonary tissue accompanying with activated pro-inflammatory signals. Meanwhile, Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) and nuclear factor erythroid-2-related factor 2 (Nrf2) signaling plays important role in metabolic/endocrine homeostasis and infection response, and it's closely associated with the anti-oxidative capacity of the body. For this reason, this review will start from the summary upon the implication of ROS accumulation, and to discuss how AMPK-Nrf2 signaling contributes to maintaining the metabolic/endocrine homeostasis and attenuates the susceptibility of pulmonary infections.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Antioxidantes/metabolismo , Sistema Endócrino/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo , Pneumonia/metabolismo , Animais , Humanos , Transdução de Sinais
7.
Front Immunol ; 11: 414, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32210977

RESUMO

Signal transducer and activator of transcription 3 (STAT3) is implicated in inflammation processing, but the mechanism of its regulation mostly remains limited to Janus kinase (JAK)-mediated phosphorylation. Although AMP-activated protein kinase (AMPK)-mediated STAT3 inactivation has got documented, the molecular signaling cascade connecting STAT3 inactivation and the anti-inflammatory role of AMPK is far from established. In the present study, we addressed the interplay between AMPK and STAT3, and revealed the important role of STAT3 inactivation in the anti-inflammatory function of AMPK in lipopolysaccharide-stressed macrophages and mice. Firstly, we found that pharmacological inhibition of STAT3 can improve the anti-inflammatory effect of AMPK in wild-type mice, and the expression of STAT3 in macrophage of mice is a prerequisite for the anti-inflammatory effect of AMPK. As to the molecular signaling cascade linking AMPK to STAT3, we disclosed that AMPK suppressed STAT3 not only by attenuating JAK signaling but also by activating nuclear factor erythroid-2-related factor-2 (Nrf2), a redox-regulating transcription factor, which consequently increased the expression of small heterodimer protein (SHP), thus repressing the transcriptional activity of STAT3. In summary, this study provided a unique set of evidence showing the relationship between AMPK and STAT3 signaling and explored a new mechanism of AMPK-driven STAT3 inactivation that involves Nrf2-SHP signaling cascade. These findings expand our understanding of the interplay between pro- and anti-inflammatory signaling pathways and are beneficial for the therapeutic development of sepsis treatments.


Assuntos
Fator 2 Relacionado a NF-E2/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Fator de Transcrição STAT3/metabolismo , Choque Séptico/metabolismo , Adenilato Quinase/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Humanos , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos ICR , Camundongos Knockout , Células RAW 264.7 , RNA Interferente Pequeno/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais
8.
Chemosphere ; 247: 125963, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32069729

RESUMO

Lead (Pb) pollution in the soil is becoming more and more serious, and lead poisoning incidents also constantly occur. Therefore, the remediation of lead pollution in the soil has attracted widespread attention. In this study, heavy metal lead in soil was remediated by mechanochemical methods. The effects of different ball milling conditions on the toxic leaching concentration and morphological distribution (BCR sequential extraction procedure) of lead in contaminated soil were analyzed, including the addition of calcium dihydrogen phosphate (Ca(H2PO4)2), ball milling time, and ball milling speed. The reaction mechanism was analyzed by X-ray diffractometry (XRD), scanning electron microscopy (SEM), and a laser particle size analyzer. The results show that the optimal conditions for mechanochemical immobilization were 10% additive (Ca(H2PO4)2), milling speed of 550 rpm, and ball milling time for 2 h. Under this condition, the toxic leaching concentration of lead from contaminated soil was 4.36 mg L-1, and in the BCR sequential extraction procedure, Pb was mainly present in the residual fraction (54.96%). The mechanism of mechanochemical solidification of heavy metal lead in soil is that, during the ball milling process, the lead precipitates with Ca(H2PO4)2 to produce dense agglomerates (Pb3(PO4)2 and PbxCa10-x(PO4)6(OH)2), which fixes the lead in the soil and hampers its leaching.


Assuntos
Fosfatos de Cálcio/química , Recuperação e Remediação Ambiental/métodos , Chumbo/isolamento & purificação , Poluentes do Solo/química , Pirofosfato de Cálcio/química , Precipitação Química , Chumbo/química , Metais Pesados/química , Metais Pesados/isolamento & purificação , Microscopia Eletrônica de Varredura , Poluentes do Solo/análise , Poluentes do Solo/isolamento & purificação
9.
J Biol Chem ; 295(14): 4451-4463, 2020 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-32047109

RESUMO

Oxidative stress-induced DNA damage, the senescence-associated secretory phenotype (SASP), and impaired autophagy all are general features of senescent cells. However, the cross-talk among these events and processes is not fully understood. Here, using NIH3T3 cells exposed to hydrogen peroxide stress, we show that stress-induced DNA damage provokes the SASP largely via cytosolic chromatin fragment (CCF) formation, which activates a cascade comprising cGMP-AMP synthase (cGAS), stimulator of interferon genes protein (STING), NF-κB, and SASP, and that autolysosomal function inhibits this cascade. We found that CCFs accumulate in senescent cells with activated cGAS-STING-NF-κB signaling, promoting SASP and cellular senescence. We also present evidence that the persistent accumulation of CCFs in prematurely senescent cells is partially associated with a defect in DNA-degrading activity in autolysosomes and reduced abundance of activated DNase 2α. Intriguingly, we found that metformin- or rapamycin-induced activation of autophagy significantly lessened the size and levels of CCFs and repressed the activation of the cGAS-STING-NF-κB-SASP cascade and cellular senescence. These effects of autophagy activators indicated that autolysosomal function contributes to CCF clearance and SASP suppression, further supported by the fact that the lysosome inhibitor bafilomycin A1 blocked the role of autophagy-mediated CCF clearance and senescence repression.


Assuntos
Senescência Celular , Cromatina/metabolismo , Lisossomos/metabolismo , Estresse Oxidativo , Animais , Autofagia/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , GMP Cíclico/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Dano ao DNA/efeitos dos fármacos , Endodesoxirribonucleases/metabolismo , Peróxido de Hidrogênio/farmacologia , Interleucina-6/metabolismo , Proteínas de Membrana/metabolismo , Camundongos , NF-kappa B/metabolismo , Células NIH 3T3 , Nucleotidiltransferases/antagonistas & inibidores , Nucleotidiltransferases/genética , Nucleotidiltransferases/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Transdução de Sinais/efeitos dos fármacos
10.
Front Microbiol ; 10: 2576, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31781072

RESUMO

Fish are the most widespread aquaculture species and maintain complex associations with microbial consortiums. However, the ecology of these associations present in multiple microhabitats in fish remains elusive, especially on the microbial assembly in fish external (skin and gill) and internal (stomach and intestine) niches, and the relationship with the rearing environment. To understand host dependence and niche differentiation of organ-specific microbiome signatures using a 16S rRNA gene-based sequencing technique, we systematically provided characterizations of a comparative framework relevant to the microbiome of stomach, regional intestine, skin, and gill in two important farmed fish species, herbivorous grass carp (Ctenopharyngodon idella) and carnivorous southern catfish (Silurus meridionalis), and of the rearing water. The different feeding habits of grass carp and southern catfish showed a significant separation of microbial community structure, with great compositional differences across body sites within each species. Site-driven divergences relied on host species: the same types of microhabitats between grass carp and southern catfish harbored differential microbiome. Additionally, body sites had remarkably distinct communities and displayed lower alpha diversity compared to rearing water. Unexpectedly, the stomach of southern catfish had the highest microbial diversity in the digestive tract of the two co-cultured fish species. For external sites within each species, a higher diversity occurred in gill of grass carp and in skin of southern catfish. Our results unveil different topographical microbiome signatures of the co-cultured species, indicating host selection in individual-level microbial assemblages and niche differentiation at the organ scale. This work represents a foundation for understanding the comprehensive microbial ecology of cohabiting farmed fish, suggesting potential applications associated with fish microbiome that urgently needs to be assessed in polycultured operations in aquaculture.

11.
J Contam Hydrol ; 225: 103514, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31220758

RESUMO

Soil contamination caused by heavy metals has gained widespread attention from both government and public. In the present research, ball milling was utilized to remediate soil contaminated by Pb, Cu, and Zn and the influence of milling time on immobilization effectiveness was also investigated. The effectiveness of immobilization was evaluated by analyzing the leachable fraction of heavy metals from the ball-milled soil. When the milling time was 2 h, Pb, Cu, and Zn leaching concentrations decreased from 13.92 mg·L-1, 2.83 mg·L-1, and 114.42 mg·L-1 to 0.027 mg·L-1, 0.59 mg·L-1, and 0.16 mg·L-1, respectively; these values were all lower than the surface water Class III standard regulatory thresholds proposed by the Chinese Ministry of Ecology and Environment. Furthermore, the leaching characteristics of Pb, Cu, and Zn were investigated through pH-dependent tests and those results indicated that mechanical treatment improved the anti-acid ability of soil. In addition, the BCR sequential extraction procedure revealed that speciation shiftsof heavy metals are the root cause for the reduction of leaching concentrations; after ball milling of 4 h, the primary components of Pb, Cu and Zn in the soil were relatively stable (F2 + F3) and residual fraction (F4), which accounted for 76.75%, 67.06% and 48.05% of total Pb, Cu and Zn, respectively.


Assuntos
Metais Pesados , Poluentes do Solo , Poluição Ambiental , Chumbo , Solo , Zinco
12.
Chemosphere ; 227: 657-661, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31015086

RESUMO

Mechanochemical treatment with calcium polysulfide (CPS) was applied to remediate the Cr(VI) contaminated soil. The effects of parameters including milling speed, milling time, ball to powder ratio (BPR) and dosage of CPS were investigated. The effectiveness of mechanical treatment with or without CPS is estimated by analyzing the leachable fraction of Cr(VI). The results show that mechanochemical treatment with CPS can decrease and immobilize Cr in soil more quickly and efficiently with comparison to the case without additive. Under a milling speed of 500 rpm, milling time of 2 h, BPR of 9 and CPS dosage of 3%, the Cr(VI) leaching concentration significantly decreased from 115 mg L-1 to 0.51 mg L-1, much lower than the regulatory limit of 5 mg L-1. Additionally, XPS results demonstrated that Cr(VI) can be converted into Cr(III) during ball milling with CPS. The high Cr(VI) removal and Cr immobilization capacity makes mechanochemical treatment a great potential in field remediation.


Assuntos
Compostos de Cálcio/química , Cromo/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/análise , Solo/química , Sulfetos/química , Fatores de Tempo
13.
Chemosphere ; 212: 540-547, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30165280

RESUMO

In this research, mechanochemical reduction was carried out to remediate Cr(VI) contaminated soil, and the reduction effectiveness was evaluated by analyzing the corresponding leachable fraction obtained through the toxicity characteristic leaching procedure (TCLP) proposed by the EPA. The results indicated that mechanochemical reduction can efficiently reduce the Cr(VI) concentration in the leachate. Under a milling time of 2 h, milling speed of 500 rpm, ball-to-powder weight ratio of 14 and Na2S dosage of 5%, the Cr(VI) leaching concentration significantly decreased from 663.98 mg L-1 to 0.84 mg L-1, much lower than the regulatory limit of 5 mg L-1. In addition, the significant decrease in Cr(VI) was mainly due to the reduction of Cr(VI) to Cr(III), as supported by X-ray photoelectron spectroscopy (XPS). The mechanochemical reduction with mechanism proposed in this experiment may involve two major processes: solidification and reduction (stabilization).


Assuntos
Cromo/química , Poluição Ambiental/análise , Recuperação e Remediação Ambiental/métodos , Poluentes do Solo/química , Solo/química , Sulfetos/química , Poluentes do Solo/análise
14.
Food Chem ; 256: 244-251, 2018 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-29606444

RESUMO

This study aimed to evaluate the effects of thermally processed diet (TD) on the muscle nutritional values of southern catfish in two experiments (named E1 and E2). Compared to non-thermally processed diet (ND), TD did not significantly affect proximate composition of southern catfish, but increased moisture content and decreased protein content in E1. Meanwhile, it had no effect on overall fatty acid profiles of the catfish rich in PUFA. Southern catfish had high proportions of indispensable amino acids (IAA, 44.6-46.4% of total fatty acids), with the highest contents of lysine (1551-1808 mg/100 g wet weight muscle). However, TD altered profiles of the IAA, particularly decreased 68.5% and 68.4% of methionine, and 9.5% and 10.7% of lysine in E1 and E2, respectively. Conversely, it increased 45.4% and 83.4% of dispensable fatty acid proline. These results suggest TD could affect the nutritional quality of protein rather than fat in farmed fish.


Assuntos
Aminoácidos/metabolismo , Peixes-Gato/metabolismo , Dieta , Ácidos Graxos/metabolismo , Músculos/efeitos dos fármacos , Músculos/metabolismo , Temperatura , Ração Animal/análise , Animais , Valor Nutritivo
15.
Front Microbiol ; 9: 495, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29616008

RESUMO

Host development influences gut microbial assemblies that may be confounded partly by dietary shifts and the changing environmental microbiota during ontogenesis. However, little is known about microbial colonization by excluding dietary effects and compositional differences in microbiota between the gut and environment at different ontogenetic stages. Herein, a developmental gut microbial experiment under controlled laboratory conditions was conducted with carnivorous southern catfish Silurus meridionalis fed on an identical prey with commensal and abundant microbiota. In this study, we provided a long-term analysis of gut microbiota associated with host age at 8, 18, 35, 65, and 125 day post-fertilization (dpf) and explored microbial relationships among host, food and water environment at 8, 35, and 125 dpf. The results showed that gut microbial diversity in southern catfish tended to increase linearly as host aged. Gut microbiota underwent significant temporal shifts despite similar microbial communities in food and rearing water during the host development and dramatically differed from the environmental microbiota. At the compositional abundance, Tenericutes and Fusobacteria were enriched in the gut and markedly varied with host age, whereas Spirochaetes and Bacteroidetes detected were persistently the most abundant phyla in food and water, respectively. In addition to alterations in individual microbial taxa, the individual differences in gut microbiota were at a lower level at the early stages than at the late stages and in which gut microbiota reached a stable status, suggesting the course of microbial successions. These results indicate that host development fundamentally shapes a key transition in microbial community structure, which is independent of dietary effects. In addition, the dominant taxa residing in the gut do not share their niche habitats with the abundant microbiota in the surrounding environment. It's inferred that complex gut microbiota could not be simple reflections of environmental microbiota. The knowledge enhances the understanding of gut microbial establishment in the developing fish and provides a useful resource for such studies of fish- or egg-associated microbiota in aquaculture.

16.
Front Microbiol ; 8: 1531, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28848535

RESUMO

The fish intestinal microbiota is affected by dietary shifts or diet-related seasonal fluctuations making it highly variable and dynamic. It assists with the digestion and absorption of food that is a common, yet dynamic process. However, fundamental dynamics of microbial ecology associated with food digestion in intestine and stomach are poorly understood in fish. We selected the southern catfish, Silurus meridionalis, as the targeted species, owing to its foraging behavior with a large meal that can assure clear periodic rhythms in food digestion, to study spatial variations of the microbial community along the gastrointestinal (GI) tract. We further evaluated temporal microbial dynamics by collecting GI tract samples at time intervals 03, 12, and 24h after feeding. High-throughput sequencing results showed higher microbial diversity in the stomach than in the intestine and distinguishable community structures between stomach and intestine. Firmicutes were dominated by both Clostridium and unclassified Clostridiaceae, which was the most abundant taxon in the stomach, whereas Fusobacteria were dominated by Cetobacterium, which prevailed in the intestine. Firmicutes was significantly increased and Fusobacteria was decreased after feeding. Furthermore, inter-stomach microbial variability was greater than inter-intestine microbial variability. These results demonstrate that GI microbial assemblies are specific per anatomical site and are highly dynamic during food digestion, indicating that digestive status and/or sampling time are factors potentially influencing the microbial compositions. Furthermore, the finding of high spatial and temporal variations of the microbial community along the GI tract suggests limitations of single sampling regime to study food-derived microbial ecology.

17.
J Pharm Biomed Anal ; 141: 210-221, 2017 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-28448890

RESUMO

Neotuberostemonine (NS) and tuberostemonine (TS), a pair of stereoisomers, are the active components contained in Stemona tuberosa, an antitussive herbal medicine in China. Two isomers have different pharmacological efficacies, which will be related with their in vivo disposition. However, the metabolic fates of NS and TS remain unknown. A method of high performance liquid chromatography/quadrupole time-of-flight mass spectrometry coupled with mass detect filter technique was established to investigate the metabolites in rat plasma, bile, urine, and feces after oral administration of the equal doses of NS and TS. The results showed that NS produced 48 phase I metabolites, including NS, 3 hydrolyzed, 14 hydroxylated, 20 monohydrolyzed+hydroxylated and 10 dihydrolyzed+hydroxylated metabolites. The number of detected NS metabolites was 11, 39, 22 and 30 in plasma, bile, urine and feces. TS yielded 23 phase I metabolites, including TS, 3 hydrolyzed, 7 hydroxylated, 9 monohydrolyzed+hydroxylated and 3 dihydrolyzed+hydroxylated metabolites. Besides, TS yielded 9 phase II metabolites, including 1 glucuronic acid and 2 glutathione conjugates, and the later further degraded and modified into cysteine-glycine, cysteine and N-acetylcysteine conjugates. The number of detected TS metabolites was 9, 24, 24 and 15 in plasma, bile, urine and feces. Different metabolic patterns may be one of the main reasons leading to different pharmacological effects of NS and TS.


Assuntos
Alcaloides/análise , Lactonas/análise , Animais , Cromatografia Líquida de Alta Pressão , Espectrometria de Massas , Metaboloma , Ratos , Ratos Sprague-Dawley , Espectrometria de Massas em Tandem
18.
Pharmacol Rep ; 69(2): 252-259, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28126641

RESUMO

Metabolomics is a powerful emerging tool for the identification of biomarkers and the exploration of metabolic pathways in a high-throughput manner. As an administration site for percutaneous absorption, the skin has a variety of metabolic enzymes, except other than hepar. However, technologies to fully detect dermal metabolites remain lacking. Skin metabolomics studies have mainly focused on the regulation of dermal metabolites by drugs or on the metabolism of drugs themselves. Skin metabolomics techniques include collection and preparation of skin samples, data collection, data processing and analysis. Furthermore, studying dermal metabolic effects via metabolomics can provide novel explanations for the pathogenesis of some dermatoses and unique insights for designing targeted prodrugs, promoting drug absorption and controlling drug concentration. This paper reviews current progress in the field of skin metabolomics, with a specific focus on dermal drug delivery systems and dermatosis.


Assuntos
Pró-Fármacos/administração & dosagem , Pró-Fármacos/metabolismo , Pele/metabolismo , Administração Cutânea , Animais , Biomarcadores/metabolismo , Sistemas de Liberação de Medicamentos/métodos , Humanos , Metabolômica/métodos , Absorção Cutânea/fisiologia
19.
Phytother Res ; 29(12): 1974-81, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26514546

RESUMO

This study aims to investigate the additive or synergistic effects and mechanism of intestinal absorption of extracts from two commonly used 'dispelling-wind' TCM botanical drugs [roots of Angelica dahurica (Hoffm.) Benth. & Hook. f. ex Franch. & Sav. (RAD) and Saposhnikovia divaricata (Turcz.) Schischk. (RSD)] using chlorogenic acid as a marker substance. Ex vivo everted intestinal sac and in situ single pass perfusion methods using rats were employed to investigate the effects of two TCM botanical drugs extracts on the intestinal absorption of chlorogenic acid. Both the extracts of RAD and RSD showed synergistic properties on the intestinal absorption of chlorogenic acid. The verapamil (a P-gp inhibitor) and intestinal dysbacteriosis model induced by norfloxacin increased the P(app) and K(a) of intestinal absorption of chlorogenic acid. These synergistic effects on intestinal absorption in a rat model can be correlated with the inhibition of P-gp and regulation of gut microbiota. This experimental approach has helped to better understand changes in the absorption of chlorogenic acid under different conditions.


Assuntos
Ácido Clorogênico/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Absorção Intestinal/efeitos dos fármacos , Mucosa Intestinal/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/antagonistas & inibidores , Angelica/química , Animais , Apiaceae/química , Sinergismo Farmacológico , Intestinos/efeitos dos fármacos , Masculino , Extratos Vegetais/farmacologia , Ratos , Ratos Sprague-Dawley , Verapamil/farmacologia
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