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1.
Cell ; 149(3): 656-70, 2012 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-22541435

RESUMO

Tumor maintenance relies on continued activity of driver oncogenes, although their rate-limiting role is highly context dependent. Oncogenic Kras mutation is the signature event in pancreatic ductal adenocarcinoma (PDAC), serving a critical role in tumor initiation. Here, an inducible Kras(G12D)-driven PDAC mouse model establishes that advanced PDAC remains strictly dependent on Kras(G12D) expression. Transcriptome and metabolomic analyses indicate that Kras(G12D) serves a vital role in controlling tumor metabolism through stimulation of glucose uptake and channeling of glucose intermediates into the hexosamine biosynthesis and pentose phosphate pathways (PPP). These studies also reveal that oncogenic Kras promotes ribose biogenesis. Unlike canonical models, we demonstrate that Kras(G12D) drives glycolysis intermediates into the nonoxidative PPP, thereby decoupling ribose biogenesis from NADP/NADPH-mediated redox control. Together, this work provides in vivo mechanistic insights into how oncogenic Kras promotes metabolic reprogramming in native tumors and illuminates potential metabolic targets that can be exploited for therapeutic benefit in PDAC.


Assuntos
Adenocarcinoma/metabolismo , Modelos Animais de Doenças , Neoplasias Pancreáticas/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Animais , Humanos , Camundongos , Proteínas Proto-Oncogênicas p21(ras)/genética , Transcrição Gênica
2.
J Biol Chem ; 300(6): 107340, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38705390

RESUMO

Triclosan (TCS) is an antimicrobial toxicant found in a myriad of consumer products and has been detected in human tissues, including breastmilk. We have evaluated the impact of lactational TCS on UDP-glucuronosyltransferase 1A1 (UGT1A1) expression and bilirubin metabolism in humanized UGT1 (hUGT1) neonatal mice. In hUGT1 mice, expression of the hepatic UGT1A1 gene is developmentally delayed resulting in elevated total serum bilirubin (TSB) levels. We found that newborn hUGT1 mice breastfed or orally treated with TCS presented lower TSB levels along with induction of hepatic UGT1A1. Lactational and oral treatment by gavage with TCS leads to the activation of hepatic nuclear receptors constitutive androstane receptor (CAR), peroxisome proliferator-activated receptor alpha (PPARα), and stress sensor, activating transcription factor 4 (ATF4). When CAR-deficient hUGT1 mice (hUGT1/Car-/-) were treated with TCS, TSB levels were reduced with a robust induction of hepatic UGT1A1, leaving us to conclude that CAR is not tied to UGT1A1 induction. Alternatively, when PPARα-deficient hUGT1 mice (hUGT1/Pparα-/-) were treated with TCS, hepatic UGT1A1 was not induced. Additionally, we had previously demonstrated that TCS is a potent inducer of ATF4, a transcriptional factor linked to the integrated stress response. When ATF4 was deleted in liver of hUGT1 mice (hUGT1/Atf4ΔHep) and these mice treated with TCS, we observed superinduction of hepatic UGT1A1. Oxidative stress genes in livers of hUGT1/Atf4ΔHep treated with TCS were increased, suggesting that ATF4 protects liver from excessive oxidative stress. The increase oxidative stress may be associated with superinduction of UGT1A1. The expression of ATF4 in neonatal hUGT1 hepatic tissue may play a role in the developmental repression of UGT1A1.


Assuntos
Fator 4 Ativador da Transcrição , Animais Recém-Nascidos , Bilirrubina , Glucuronosiltransferase , Fígado , PPAR alfa , Triclosan , Animais , Glucuronosiltransferase/metabolismo , Glucuronosiltransferase/genética , PPAR alfa/metabolismo , PPAR alfa/genética , Camundongos , Fator 4 Ativador da Transcrição/metabolismo , Fator 4 Ativador da Transcrição/genética , Triclosan/farmacologia , Humanos , Bilirrubina/farmacologia , Bilirrubina/metabolismo , Fígado/metabolismo , Fígado/efeitos dos fármacos , Camundongos Knockout , Feminino , Receptor Constitutivo de Androstano , Receptores Citoplasmáticos e Nucleares/metabolismo , Receptores Citoplasmáticos e Nucleares/genética
3.
J Biol Chem ; 299(3): 102955, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36720308

RESUMO

Inorganic arsenic (iAs) is an environmental toxicant that can lead to severe health consequences, which can be exacerbated if exposure occurs early in development. Here, we evaluated the impact of oral iAs treatment on UDP-glucuronosyltransferase 1A1 (UGT1A1) expression and bilirubin metabolism in humanized UGT1 (hUGT1) mice. We found that oral administration of iAs to neonatal hUGT1 mice that display severe neonatal hyperbilirubinemia leads to induction of intestinal UGT1A1 and a reduction in total serum bilirubin values. Oral iAs administration accelerates neonatal intestinal maturation, an event that is directly associated with UGT1A1 induction. As a reactive oxygen species producer, oral iAs treatment activated the Keap-Nrf2 pathway in the intestinal tract and liver. When Nrf2-deficient hUGT1 mice (hUGT1/Nrf2-/-) were treated with iAs, it was shown that activated Nrf2 contributed significantly toward intestinal maturation and UGT1A1 induction. However, hepatic UGT1A1 was not induced upon iAs exposure. We previously demonstrated that the nuclear receptor PXR represses liver UGT1A1 in neonatal hUGT1 mice. When PXR was deleted in hUGT1 mice (hUGT1/Pxr-/-), derepression of UGT1A1 was evident in both liver and intestinal tissue in neonates. Furthermore, when neonatal hUGT1/Pxr-/- mice were treated with iAs, UGT1A1 was superinduced in both tissues, confirming PXR release derepressed key regulatory elements on the gene that could be activated by iAs exposure. With iAs capable of generating reactive oxygen species in both liver and intestinal tissue, we conclude that PXR deficiency in neonatal hUGT1/Pxr-/- mice allows greater access of activated transcriptional modifiers such as Nrf2 leading to superinduction of UGT1A1.


Assuntos
Arsênio , Glucuronosiltransferase , Fator 2 Relacionado a NF-E2 , Receptor de Pregnano X , Animais , Camundongos , Animais Recém-Nascidos , Arsênio/toxicidade , Bilirrubina/sangue , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Fígado/enzimologia , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Receptor de Pregnano X/genética , Receptor de Pregnano X/metabolismo
4.
Langmuir ; 40(29): 15059-15070, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38995619

RESUMO

Utilizing energy directly from the sun, solar water evaporation drives the global hydrological cycle and produces freshwater from saline water in the oceans and on land. As water is a poor solar absorber, a photothermal material is needed to facilitate the conversion of photons to thermal energy and increase the efficiency of solar desalination. However, the current photothermal materials are less efficient and expensive to be manufactured. Inspired by nature, we created a new photothermal material called a wood biochar monolith (WBM) by carbonizing wood using the pyrolysis process at 1000 °C and subsequently steaming at high pressure. Under low light intensity (193 W/m2), the light to vapor efficiency of maple WBM is more than 100%. The outstanding performance of WBM is attributed to (1) the facilitated water transport in the hierarchical, open-pore network preserved from the wood precursor in WBM and (2) the reduced evaporation enthalpy of confined water in WBM and the high broadband sunlight absorptivity of WBM. Moreover, the high evaporation rate causes the temperature of WBM to be lower than that of the surrounding water, enabling thermal energy harvesting by WBM from water and making a light-to-vapor efficiency of >100% feasible. This discovery offers opportunities for developing low-cost, high-performance water desalination or humidification devices deployable in remote areas with nonconcentrated natural sunlight.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38981978

RESUMO

OBJECTIVE: This systematic review aims to assess the accuracy of the COMPASS-CAT tool in predicting venous thromboembolism (VTE) among cancer patients. METHODS: Relevant studies were searched in PubMed, Web of Science, The Cochrane Library, Embase, CINAHL, OVID, CBM, CNKI, WanFang Data, and VIP database from their inception up to April 19, 2023. The quality of studies was appraised using the diagnostic test accuracy study bias assessment tool (QUADAS-2). Quantitative analysis was performed using Stata MP 17.0. RESULTS: Thirteen studies involving 8,665 patients were included. Meta-analysis indicated that the COMPASS-CAT score had a pooled sensitivity of 0.76 [95%CI (0.61, 0.86)], specificity of 0.67 [95%CI (0.52, 0.79)], positive likelihood ratio of 2.3 [95%CI (1.7, 3.1)], negative likelihood ratio of 0.36 [95%CI (0.23, 0.54)], diagnostic odds ratio of 6 [95%CI (4, 10)], and an area under the Summary Receiver Operating Characteristic (SROC) curve (AUC) of 0.77 [95%CI (0.74, 0.81)]. Funnel plots indicated no publication bias. Meta-regression and subgroup analysis suggested that country and diagnostic setting might be potential sources of heterogeneity. The sensitivity of the COMPASS-CAT assessment tool in international outpatient settings was 0.94 with an AUC of 0.86, while in domestic inpatient settings, the sensitivity was 0.65 with an AUC of 0.78. CONCLUSION: The COMPASS-CAT score had a certain diagnostic value for VTE in cancer patients and can effectively identify patients at risk of VTE. Most studies focus on patients with lung cancer. Future research should investigate more tumor types, and high-quality, large-sample, multi-center prospective studies on larger populations with cancers are warranted.

6.
J Stroke Cerebrovasc Dis ; 33(4): 107634, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38342274

RESUMO

BACKGROUND: Intracranial aneurysm (IA) is a common cerebrovascular disease and the leading cause of spontaneous subarachnoid hemorrhage. Recent evidence suggests that gut microbiota is involved in the pathophysiological process of IA through the gut-brain axis. However, the role of gut inflammation in the development of IA has yet to be clarified. Our study aimed to investigate whether fecal calprotectin (FC) level, a sensitive marker of gut inflammation, is correlated with the development of IA and the prognosis of patients with ruptured IA (RIA). METHODS: 182 patients were collected from January 2022 to January 2023, including 151 patients with IA and 31 healthy individuals. 151 IA patients included 109 patients with unruptured IA (UIA) and 42 patients with RIA. The FC level was measured by enzyme-linked immunosorbent assay. Other detailed information was obtained from an electronic medical record system. RESULTS: Compared with healthy controls, the FC levels in patients with IA were increased (P < 0.0001). Patients with RIA had significantly higher FC levels than UIA patients (P < 0.0001). Moreover, the FC level in RIA patients with unfavorable outcomes was higher than in RIA patients with favorable outcomes. Logistic regression analysis showed that the elevated FC level was an independent risk factor for a 3-month poor prognosis in patients with RIA (OR=1.005, 95% CI = 1.000 -1.009, P = 0.044). CONCLUSION: Fecal calprotectin level is significantly elevated in IA patients, especially those with RIA. FC is a novel biomarker of 3-month poor outcomes in RIA patients.


Assuntos
Aneurisma Roto , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Humanos , Aneurisma Intracraniano/complicações , Aneurisma Intracraniano/diagnóstico , Hemorragia Subaracnóidea/etiologia , Aneurisma Roto/etiologia , Biomarcadores , Inflamação/complicações
7.
J Environ Manage ; 351: 119935, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38154221

RESUMO

Heavy metal and antibiotic-resistant bacteria from livestock feces are ecological and public health problems. However, the distribution and relationships of antibiotic resistance genes (ARGs), heavy metal resistance genes (HMRGs), and virulence factors (VFs) and their transmission mechanisms remain unclear. Therefore, we investigated the resistance of Escherichia coli, the prevalence of its ARGs, HMRGs, and VFs, and their transmission mechanisms in livestock fresh feces (FF), composted feces (CF), and fertilized soil (FS). In total, 99.54% (n = 221) and 91.44% (n = 203) of E. coli were resistant to at least one antibiotic and one heavy metal, respectively. Additionally, 72.52% (n = 161) were multi-drug resistant (MDR), of which Cu-resistant E. coli accounted for 72.67% (117/161). More than 99.34% (88/89) of E. coli carried multidrug ARGs, VFs, and the Cu resistance genes cueO and cusABCRFS. The Cu resistance genes cueO and cusABCRFS were mainly located on chromosomes, and cueO and cusF were positively associated with HMRGs, ARGs, and VFs. The Cu resistance genes pcoABCDRS were located on the plasmid pLKYL-P02 flanked by ARGs in PF18C from FF group and on chromosomes flanked by HMRGs in SAXZ1-1 from FS group. These results improved our understanding of bacterial multidrug and heavy metal resistance in the environment.


Assuntos
Antibacterianos , Metais Pesados , Animais , Antibacterianos/farmacologia , Escherichia coli/genética , Esterco/microbiologia , Gado , Solo , Genes Bacterianos , Metais Pesados/farmacologia , Bactérias/genética
8.
Microb Ecol ; 85(1): 232-246, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35064809

RESUMO

The decline in soil nutrients is becoming a major concern of soil degradation. The possibility of using organic waste as a soil additive to increase nutrients and essential components is significant in soil quality protection and waste management. The aim of this study was to investigate the effects of composted spent mushroom substrate (MS), giant panda feces (PF), and cattle manure (CM) as organic fertilizers in soil microbial communities and metabolites in blueberry orchard in China, which were measured by using high-throughput sequencing and gas chromatography-mass spectrometry (GC-MS)-based metabolomics. Altogether, 45.66% of the bacterial operational taxonomic units (OTUs) and 9.08% of the fungal OTUs were detected in all treatments. Principal coordinates analysis demonstrated that the bacterial and fungal communities in MS and PF treatments were similar, whereas the communities in the not-organic fertilized control (CK) were significantly different from those in the organic fertilizer treatments. Proteobacteria, Acidobacteria, and Bacteroidetes were the dominant bacterial phyla, and Basidiomycota, Ascomycota, and Mortierellomycota the dominant fungal phyla. Redundancy analysis indicated that pH and available potassium were the main factors determining the composition of microbial communities. The fungal genera Postia, Cephalotrichum, and Thermomyces increased in organic fertilizer treatments, and likely promoted the degradation of organic fertilizers into low molecular-weight metabolites (e.g., amino acids). PCA and PLS-DA models showed that the metabolites in CK were different from those in the other three treatments, and those in CM were clearly different from those in MS and PF. Co-occurrence network analysis showed that several taxa correlated positively with amino acid contents. The results of this study provide new insights into organic waste reutilization and new directions for further studies.


Assuntos
Ascomicetos , Mirtilos Azuis (Planta) , Microbiota , Animais , Bovinos , Solo/química , Fertilizantes/análise , Mirtilos Azuis (Planta)/metabolismo , Nitrogênio/metabolismo , Bactérias , Ascomicetos/metabolismo , Microbiologia do Solo
9.
Appl Microbiol Biotechnol ; 107(22): 6985-6998, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37702791

RESUMO

The presence of cypermethrin in the environment and food poses a significant threat to human health. Lactic acid bacteria have shown promise as effective absorbents for xenobiotics and well behaved in wide range of applications. This study aimed to characterize the biosorption behavior of cypermethrin by Lactiplantibacillus plantarum RS60, focusing on cellular components, functional groups, kinetics, and isotherms. Results indicated that RS60 exopolysaccharides played a crucial role removing cypermethrin, with the cell wall and protoplast contributing 71.50% and 30.29% to the overall removal, respectively. Notably, peptidoglycans exhibited a high affinity for cypermethrin binding. The presence of various cellular surface groups including -OH, -NH, -CH3, -CH2, -CH, -P = O, and -CO was responsible for the efficient removal of pollutants. Additionally, the biosorption process demonstrated a good fit with pseudo-second-order and Langmuir-Freundlich isotherm. The biosorption of cypermethrin by L. plantarum RS60 involved complex chemical and physical interactions, as well as intraparticle diffusion and film diffusion. RS60 also effectively reduced cypermethrin residues in a fecal fermentation model, highlighting its potential in mitigating cypermethrin exposure in humans and animals. These findings provided valuable insights into the mechanisms underlying cypermethrin biosorption by lactic acid bacteria and supported the advancement of their application in environmental and health-related contexts. KEY POINTS: • Cypermethrin adsorption by L. plantarum was clarified. • Cell wall and protoplast showed cypermethrin binding ability. • L. plantarum can reduce cypermethrin in a fecal fermentation model.

10.
Proc Natl Acad Sci U S A ; 117(49): 31259-31266, 2020 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-33229553

RESUMO

Triclosan (TCS), employed as an antiseptic and disinfectant, comes into direct contact with humans through a plethora of consumer products and its rising environmental release. We have demonstrated that TCS promotes liver tumorigenesis in mice, yet the biological and molecular mechanisms by which TCS exerts its toxicity, especially in early stages of liver disease, are largely unexplored. When mice were fed a high-fat diet (HFD), we found that fatty liver and dyslipidemia are prominent early signs of liver abnormality induced by TCS. The presumably protective HFD-induced hepatic expression of the metabolic regulator fibroblast growth factor 21 (FGF21) was blunted by TCS. TCS-altered Fgf21 expression aligned with aberrant expression of genes encoding metabolic enzymes manifested as profound systemic metabolic changes that disturb homeostasis of amino acids, fatty acids, and glucose. Using a type 1 diabetic animal model, TCS potentiates and accelerates the development of steatohepatitis and fibrosis, accompanied by increased levels of hepatic lipid droplets and oxidative stress. Analysis of fecal samples revealed that HFD-fed mice exhibited a reduction in fecal species richness, and that TCS further diminished microbial diversity and shifted the bacterial community toward lower Bacteriodetes and higher Firmicutes, resembling changes in microbiota composition in nonalcoholic steatohepatitis (NASH) patients. Using reverse-genetic approaches, we demonstrate that, along with HFD, TCS induces hepatic steatosis and steatohepatitis jointly regulated by the transcription factor ATF4 and the nuclear receptor PPARα, which participate in the transcriptional regulation of the Fgf21 gene. This study provides evidence linking nutritional imbalance and exposure to TCS with the progression of NASH.


Assuntos
Fatores de Crescimento de Fibroblastos/genética , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , PPAR alfa/genética , Triclosan/farmacologia , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Ácidos Graxos/biossíntese , Fatores de Crescimento de Fibroblastos/antagonistas & inibidores , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Fígado/efeitos dos fármacos , Fígado/patologia , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/etiologia , Cirrose Hepática/genética , Cirrose Hepática/patologia , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/patologia , Obesidade/tratamento farmacológico , Obesidade/etiologia , Obesidade/genética , Obesidade/patologia
11.
Drug Metab Dispos ; 50(1): 33-42, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34697081

RESUMO

The human UDP-glucuronosyltransferases (UGTs) represent an important family of drug-metabolizing enzymes, with UGT1A1 targeting the conjugation and detoxification of many exogenous substances, including pharmaceutical drugs. In this study we generated humanized UGT1A1 mice expressing the human UGT1A1 gene in either liver (hUGT1A1HEP ) or intestine (hUGT1A1GI ), enabling experiments to examine tissue-specific properties of UGT1A1-specific glucuronidation. Hepatic and intestinal tissue-specific expression and function of UGT1A1 were demonstrated. Although the liver is considered a major organ for detoxification, intestinal UGT1A1 is an important contributor for drug clearance. Mice were challenged with irinotecan (CPT-11), a prodrug hydrolyzed by carboxylesterases to form the active metabolite 7-ethyl-10-hydroxycamptothecin (SN-38) and detoxified by UGT1A1. Humanized UGT1A1HEP mice that have no intestinal UGT1A1 displayed a greater lethality rate when exposed to CPT-11 than hUGT1A1GI mice. When exposed to a low dose of CPT-11 (10 mg/kg), hUGT1A1HEP mice displayed greater intestinal inflammatory (IL-1ß and IL-6) insult in addition to p53-triggered apoptotic responses. In vitro studies with intestinal crypt organoids exposed to CPT-11 confirmed the results observed in vivo and indicated that CPT-11 impacts stemness, apoptosis, and endoplasmic reticulum (ER) stress in organoids deficient in UGT1A1. When we examined the induction of ER stress in organoids with thapsigargin, an inhibitor of sarco/endoplasmic reticulum Ca2+ ATPase, apoptosis and the caspase surge that occurred in hUGT1A1HEP mice were blocked in hUGT1A1GI organoids. This study reveals the importance of intestinal UGT1A1 in preventing inflammation, apoptosis, and loss of stemness capacity upon systemic challenge with an important chemotherapeutic agent. SIGNIFICANCE STATEMENT: Hepatic and intestinal UGT1A1 play a key role in the metabolism and detoxification of endogenous and exogenous compounds. The use of tissue-specific humanized models expressing UGT1A1 in liver or intestine has confirmed the relevance of the intestinal tract in the detoxification of irinotecan. Mechanistic studies using intestinal organoids highlighted the importance of UGT1A1 in reducing inflammation, apoptosis, and loss of stemness. These new models provide valuable tools for studying tissue-specific glucuronidation of substances that are metabolized by human UGT1A1.


Assuntos
Glucuronosiltransferase/metabolismo , Intestinos/metabolismo , Irinotecano/toxicidade , Animais , Apoptose/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Enterite/induzido quimicamente , Enterite/patologia , Glucuronosiltransferase/genética , Humanos , Intestinos/enzimologia , Intestinos/patologia , Fígado/enzimologia , Masculino , Camundongos , Camundongos Transgênicos , Microssomos Hepáticos , Células-Tronco
12.
J Appl Microbiol ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36626738

RESUMO

AIMS: Beads containing heat-inactivated bacterial biomaterial (BBBs) were prepared for removal of cypermethrin (CPM) and the conditions for this removal were evaluated and optimized via orthogonal experiments. The adsorption characteristics of BBBs and the binding mechanism were then explored. METHODS AND RESULTS: Single-factor and orthogonal experiments were carried out to optimize five factors affecting the production and effectivity of the beads. The adsorption rate of CPM could reach 98% with beads prepared under optimized conditions: equal volumes of Lactobacillus cell debris derived from 1 × 1011 CFU; 2% hydroxypropyl-ß-cyclodextrin and 2.5% activated carbon concentration, were mixed to give mixture TM, and this and SA, was mixed 1:4 with sodium alginate (SA) and beads were prepared using a 26-Gauge needle). The best adsorption conditions were initial CPM concentration of 10 mg l-1, incubation time of 24 h, and rotational speed of 180 rpm. BBBs have a well-formed structure and abundant surface functional groups, such as -COOH, -OH, -NH, -CH, -CO, -C = C. The adsorption process conformed to pseudo-second-order kinetic, and it was also a Freundlich monolayer adsorption, and the calculated maximum adsorption capacity was 9.69 mg g-1 under optimized conditions. CONCLUSIONS: BBBs showed the highest CPM removal capacity and a good tolerance ability.

13.
J Appl Microbiol ; 2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36626792

RESUMO

AIMS: Beads containing heat-inactivated bacterial biomaterial (BBBs) were prepared for removal of cypermethrin (CPM) and the conditions for this removal were evaluated and optimized via single-factor coupled orthogonal experiments based on five factors. The adsorption characteristics of BBBs and the binding mechanism were then explored. METHODS AND RESULTS: Results showed that the adsorption rate of CPM could reach 98% with beads prepared under optimized conditions: equal volumes of Lactobacillus cell debris derived from 1×1011 CFU; 2% hydroxypropyl-ß-cyclodextrin and 2.5% activated carbon concentration, were mixed to give mixture TM, and this and SA, was mixed 1:4 with sodium alginate (SA) and beads were prepared using a 26-Gauge needle). The best adsorption conditions were initial CPM concentration of 10 mg l-1, incubation time of 24 h, and rotational speed of 180 rpm. BBBs have a well-formed structure and abundant surface functional groups, such as -COOH, -OH, -NH, -CH, -CO, -C=C. The adsorption process conformed to pseudo-second-order kinetic, and it was also a Freundlich monolayer adsorption, and the calculated maximum adsorption capacity was 9.69 mg g-1 under optimized conditions. CONCLUSIONS: BBBs showed the highest CPM removal capacity and a good tolerance ability. SIGNIFICANCE AND IMPACT OF THE STUDY: Our results provided a theoretical foundation for developing an adsorbent with heat-inactivated Lactobacillus plantarum (L. plantarum) RS60 for removing CPM in wastewater or drinks.

14.
Int J Mol Sci ; 23(10)2022 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-35628620

RESUMO

3-PBA is a major degradation intermediate of pyrethroids. Its widespread existence in the environment poses a severe threat to the ecosystem and human health. This study evaluated the adsorption capacity of L. plantarum RS20 toward 3-PBA. Batch adsorption experiments indicated that the optimal adsorption conditions were a temperature of 37 °C and initial pH of 6.0-8.0, under which the removal rate was positively correlated with the cell concentration. In addition, there was no link between the incubation time and adsorption rate. The kinetic study showed that the adsorption process fitted well with the pseudo-second-order model, and the adsorption isotherms could be described by both Langmuir and Freundlich equations. Heat and acid treatments showed that the ability of strain RS20 in removing 3-PBA was independent of microbial vitality. Indeed, it was involved with chemisorption and physisorption via the cell walls. The cell walls made the highest contribution to 3-PBA removal, according to the adsorption experiments using different cellular components. This finding was further reconfirmed by SEM. FTIR spectroscopy analysis indicated that carboxyl, hydroxyl, amino groups, and -C-N were the functional sites for the binding of 3-PBA. The co-culture experiments showed that the adsorption of strain RS20 enhanced the degradation of 3-PBA by strain SC-1. Strain RS20 could also survive and effectively remove 3-PBA in simulated digestive juices. Collectively, strain RS20 could be employed as a biological detoxification agent for humans and animals by eliminating 3-PBA from foods, feeds, and the digestive tract in the future.


Assuntos
Lactobacillus plantarum , Poluentes Químicos da Água , Adsorção , Benzoatos , Ecossistema , Poluentes Químicos da Água/química
15.
Drug Metab Dispos ; 49(1): 12-19, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33154041

RESUMO

UDP-glucuronosyltransferase (UGT) 1A1 is the only transferase capable of conjugating serum bilirubin. However, temporal delay in the development of the UGT1A1 gene leads to an accumulation of serum bilirubin in newborn children. Neonatal humanized UGT1 (hUGT1) mice, which accumulate severe levels of total serum bilirubin (TSB), were treated by oral gavage with obeticholic acid (OCA), a potent FXR agonist. OCA treatment led to dramatic reduction in TSB levels. Analysis of UGT1A1 expression confirmed that OCA induced intestinal and not hepatic UGT1A1. Interestingly, Cyp2b10, a target gene of the nuclear receptor CAR, was also induced by OCA in intestinal tissue. In neonatal hUGT1/Car -/- mice, OCA was unable to induce CYP2B10 and UGT1A1, confirming that CAR and not FXR is involved in the induction of intestinal UGT1A1. However, OCA did induce FXR target genes, such as Shp, in both intestines and liver with induction of Fgf15 in intestinal tissue. Circulating FGF15 activates hepatic FXR and, together with hepatic Shp, blocks Cyp7a1 and Cyp7b1 gene expression, key enzymes in bile acid metabolism. Importantly, the administration of OCA in neonatal hUGT1 mice accelerates intestinal epithelial cell maturation, which directly impacts on induction of the UGT1A1 gene and the reduction in TSB levels. Accelerated intestinal maturation is directly controlled by CAR, since induction of enterocyte marker genes sucrase-isomaltase, alkaline phosphatase 3, and keratin 20 by OCA does not occur in hUGT1/Car -/- mice. Thus, new findings link an important role for CAR in intestinal UGT1A1 induction and its role in the intestinal maturation pathway. SIGNIFICANCE STATEMENT: Obeticholic acid (OCA) activates FXR target genes in both liver and intestinal tissues while inducing intestinal UGT1A1, which leads to the elimination of serum bilirubin in humanized UGT1 mice. However, the induction of intestinal UGT1A1 and the elimination of bilirubin by OCA is driven entirely by activation of intestinal CAR and not FXR. The elimination of serum bilirubin is based on a CAR-dependent mechanism that facilitates the acceleration of intestinal epithelium cell differentiation, an event that underlies the induction of intestinal UGT1A1.


Assuntos
Bilirrubina/metabolismo , Ácido Quenodesoxicólico/análogos & derivados , Receptor Constitutivo de Androstano/metabolismo , Glucuronosiltransferase/metabolismo , Intestinos , Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares , Animais , Animais Recém-Nascidos , Diferenciação Celular/fisiologia , Ácido Quenodesoxicólico/farmacocinética , Fármacos Gastrointestinais/farmacocinética , Humanos , Mucosa Intestinal/crescimento & desenvolvimento , Mucosa Intestinal/fisiologia , Intestinos/crescimento & desenvolvimento , Intestinos/metabolismo , Camundongos , Receptores Citoplasmáticos e Nucleares/agonistas , Receptores Citoplasmáticos e Nucleares/metabolismo
16.
Drug Metab Dispos ; 48(4): 255-263, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31980500

RESUMO

Liver X receptors (LXRs), LXRα and LXRß, are nuclear receptors that regulate the metabolism of cholesterol and bile acids and are activated by oxysterols. Humanized UGT1 (hUGT1) mice express the 9-human UGT1A genes associated with the UGT1 locus in a Ugt1-null background. The expression of UGT1A1 is developmentally delayed in the liver and intestines, resulting in the accumulation of serum bilirubin during the neonatal period. Induction of UGT1A1 in newborn hUGT1 mice leads to rapid reduction in total serum bilirubin (TSB) levels, a phenotype measurement that allows for an accurate prediction on UGT1A1 expression. When neonatal hUGT1 mice were treated by oral gavage with the LXR agonist T0901317, TSB levels were dramatically reduced. To determine the LXR contribution to the induction of UGT1A1 and the lowering of TSB levels, experiments were conducted in neonatal hUGT1/Lxrα -/- , hUGT1/Lxrß -/- , and hUGT1/Lxrαß -/- mice treated with T0901317. Induction of liver UGT1A1 was dependent upon LXRα, with the induction pattern paralleling induction of LXRα-specific stearoyl CoA desaturase 1. However, the actions of T0901317 were also shown to display a lack of specificity for LXR, with the induction of liver UGT1A1 in hUGT1/Lxrαß -/- mice, a result associated with activation of both pregnane X receptor and constitutive androstane receptor. However, the LXR agonist GW3965 was highly selective toward LXRα, showing no impact on lowering TSB values or inducing UGT1A1 in hUGT1/Lxrα -/- mice. An LXR-specific enhancer site on the UGT1A1 gene was identified, along with convincing evidence that LXRα is crucial in maintaining constitutive expression of UGT1A1 in adult hUGT1 mice. SIGNIFICANCE STATEMENT: It has been established that activation of LXRα, and not LXRß, is responsible for the induction of liver UGT1A1 and metabolism of serum bilirubin in neonatal hUGT1 mice. Although induction of the human UGT1A1 gene is initiated at a newly characterized LXR enhancer site, allelic deletion of the Lxrα gene drastically reduces the constitutive expression of liver UGT1A1 in adult hUGT1 mice. Combined, these findings indicate that LXRα is critical for the developmental expression of UGT1A1.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Glucuronosiltransferase/metabolismo , Receptores X do Fígado/metabolismo , Animais , Animais Recém-Nascidos , Bilirrubina/sangue , Bilirrubina/metabolismo , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Glucuronosiltransferase/genética , Hidrocarbonetos Fluorados/administração & dosagem , Receptores X do Fígado/agonistas , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Transgênicos , Sulfonamidas/administração & dosagem , Uridina Difosfato Ácido Glucurônico/metabolismo
17.
Anal Bioanal Chem ; 412(5): 1049-1062, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31853602

RESUMO

Magnetic molecular imprinted polymers with ionic liquid used as an auxiliary solvent (IL@MMIPs) for the recognition of the methyl carbamate pesticide carbaryl (CBR) in foodstuff have been synthesized. The properties and application of IL@MMIPs were determined. The kinetic and isotherm adsorption processes were found to follow the pseudo-second-order and the Scatchard models, respectively. The selective experiment showed that the IL@MMIPs exhibited good selectivity to CBR compared to magnetic nonimprinted polymers with IL (IL@MNIPs). By using the IL@MMIPs as an adsorbent for the enrichment of CBR in food samples, the limit of detection (LOD, S/N = 3) and the limit of quantitation (LOQ, S/N = 10) of this method were 3 µg kg-1 and 10 µg kg-1, respectively. Compared with the traditional method, the IL@MMIP method has better recoveries (83.23-99.83%), precision (1.12-2.09%), and stabilization (intraday, 1.08-2.81%; interday, 2.26-3.30%). IL@MMIPs are an ideal adsorbent that could be applied to conveniently detect CBR in complex food, and the proposed method can be considered as a selective and sensitive alternative to traditional methods with affordable cost, avoiding the complex pretreatment procedure. Graphical abstract .


Assuntos
Carbaril/isolamento & purificação , Contaminação de Alimentos/análise , Inseticidas/análise , Líquidos Iônicos/química , Nanopartículas de Magnetita/química , Impressão Molecular , Polímeros/química , Adsorção , Cristalografia por Raios X , Cinética , Limite de Detecção , Microscopia Eletrônica de Varredura , Reprodutibilidade dos Testes , Espectroscopia de Infravermelho com Transformada de Fourier , Termodinâmica
18.
Curr Microbiol ; 77(12): 3821-3830, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32979055

RESUMO

Aflatoxins are toxic secondary metabolic products, which exert great hazards to human and animal health. Decontaminating aflatoxins from food ingredients to a threshold level is a prime concern for avoiding risks to the consumers. Biological decontamination processes of aflatoxins have received widespread attention due to their mild and environmental-friendly nature. Many reports have been published on the decontamination of aflatoxins by microorganisms, especially lactic acid bacteria (LAB), a well-explored probiotic and generally recognized as safe. The present review aims at updating the decontamination of produced aflatoxins using LAB, with an emphasis on the decontamination mechanism and influence factors for decontamination. This comprehensive analysis provides insights into the binding mechanisms between LAB and aflatoxins, facilitating the theoretical and practical application of LAB for decontaminating hazardous substances in food and agriculture.


Assuntos
Aflatoxinas , Lactobacillales , Aflatoxinas/análise , Animais , Descontaminação , Contaminação de Alimentos/análise , Humanos
19.
Proc Natl Acad Sci U S A ; 114(8): E1432-E1440, 2017 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-28167773

RESUMO

Severe neonatal hyperbilirubinemia (SNH) and the onset of bilirubin encephalopathy and kernicterus result in part from delayed expression of UDP-glucuronosyltransferase 1A1 (UGT1A1) and the inability to metabolize bilirubin. Although there is a good understanding of the early events after birth that lead to the rapid increase in serum bilirubin, the events that control delayed expression of UGT1A1 during development remain a mystery. Humanized UGT1 (hUGT1) mice develop SNH spontaneously, which is linked to repression of both liver and intestinal UGT1A1. In this study, we report that deletion of intestinal nuclear receptor corepressor 1 (NCoR1) completely diminishes hyperbilirubinemia in hUGT1 neonates because of intestinal UGT1A1 gene derepression. Transcriptomic studies and immunohistochemistry analysis demonstrate that NCoR1 plays a major role in repressing developmental maturation of the intestines. Derepression is marked by accelerated metabolic and oxidative phosphorylation, drug metabolism, fatty acid metabolism, and intestinal maturation, events that are controlled predominantly by H3K27 acetylation. The control of NCoR1 function and derepression is linked to IKKß function, as validated in hUGT1 mice with targeted deletion of intestinal IKKß. Physiological events during neonatal development that target activation of an IKKß/NCoR1 loop in intestinal epithelial cells lead to derepression of genes involved in intestinal maturation and bilirubin detoxification. These findings provide a mechanism of NCoR1 in intestinal homeostasis during development and provide a key link to those events that control developmental repression of UGT1A1 and hyperbilirubinemia.


Assuntos
Células Epiteliais/metabolismo , Hiperbilirrubinemia Neonatal/metabolismo , Mucosa Intestinal/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Animais , Animais Recém-Nascidos/metabolismo , Bilirrubina/metabolismo , Glucuronosiltransferase/metabolismo , Humanos , Quinase I-kappa B/metabolismo , Fígado/metabolismo , Camundongos
20.
Biodegradation ; 31(1-2): 139-152, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32306137

RESUMO

Pesticides introduced inadvertently or deliberately into environment by anthropogenic activity have caused growing global public concern, therefore the search of approaches for elimination of such xenobiotics should be encouraged. A cypermethrin-degrading bacterial strain Bacillus licheniformis B-1 was found to efficiently degrade carbaryl in LB medium at concentrations of 50-300 mg L-1 within 48 h, during which temperature and pH played important roles as reflected by increase in pollutant depletion. A stimulatory effect of Fe3+ and Mn2+ on microbial growth was observed, whereas Cu2+ caused inhibition of degradation. Results showed that 1-naphthol was a major transformation product of carbaryl which was further metabolised. An approximately 29 kDa carbaryl-degrading enzyme was purified from B-1 with 15.93-fold purification and an overall yield of 6.02% was achieved using ammonium sulphate precipitation, DEAE-Sepharose CL-6B anion-exchange chromatography and Sephadex G-100 gel filtration. The enzyme was identified through nano reversed-phase liquid chromatography coupled with hybrid triple quadrupole time-of-flight mass spectrometry as a phosphodiesterase (PDE). This is the first report on the characterization of carbaryl-degrading by Bacillus spp. and the role of a PDE in carbaryl-detoxifying. Also, strain B-1 showed versatile in carbosulfan, isoprocarb and chlorpyrifos degradation, demonstrating as ideal candidate for environment bioremediation.


Assuntos
Bacillus licheniformis , Clorpirifos , Biodegradação Ambiental , Carbaril , Hidrolases
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