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1.
Toxicol Lett ; 318: 86-91, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669099

RESUMO

Proton pump inhibitors (PPIs) have been used worldwide to treat gastrointestinal disorders. A recent study showed that long-term use of PPIs caused iron deficiency; however, it is unclear whether PPIs affect iron metabolism directly. We investigated the effect of PPIs on the peptide hepcidin, an important iron regulatory hormone. First, we used the FDA Adverse Event Reporting System database and analyzed the influence of PPIs. We found that PPIs, as well as H2 blockers, increased the odds ratio of iron-deficient anemia. Next, HepG2 cells were used to examine the action of PPIs and H2 blockers on hepcidin. PPIs augmented hepcidin expression, while H2 blockers did not. In fact, the PPI omeprazole increased hepcidin secretion, and omeprazole-induced hepcidin upregulation was inhibited by gene silencing or the pharmacological inhibition of the aryl hydrocarbon receptor. In mouse experiments, omeprazole also increased hepatic hepcidin mRNA expression and blood hepcidin levels. In mice treated with omeprazole, protein levels of duodenal and splenic ferroportin decreased. Taken together, PPIs directly affect iron metabolism by suppressing iron absorption through the inhibition of duodenal ferroportin via hepcidin upregulation. These findings provide a new insight into the molecular mechanism of PPI-induced iron deficiency.


Assuntos
Anemia Ferropriva/induzido quimicamente , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Duodeno/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepcidinas/metabolismo , Absorção Intestinal/efeitos dos fármacos , Ferro/sangue , Inibidores da Bomba de Prótons/toxicidade , Receptores de Hidrocarboneto Arílico/metabolismo , Anemia Ferropriva/sangue , Anemia Ferropriva/fisiopatologia , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Proteínas de Transporte de Cátions/metabolismo , Duodeno/metabolismo , Duodeno/fisiopatologia , Células Hep G2 , Hepatócitos/metabolismo , Antagonistas dos Receptores Histamínicos H2/toxicidade , Humanos , Ferro/deficiência , Masculino , Camundongos Endogâmicos C57BL , Receptores de Hidrocarboneto Arílico/genética
2.
Toxicol Lett ; 318: 74-85, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31654802

RESUMO

Metabolic flexibility defines the capacity of cells to respond to changes in nutrient status. Mitochondria are important mediators of metabolic flexibility and dysfunction is associated with metabolic inflexibility and pathology. Foodborne toxins are often overlooked as potential factors contributing to metabolic toxicity. Fusaric acid (FA), a neglected mycotoxin, is known to disrupt mitochondrial function. The aim of this study was to investigate the molecular mechanisms underlying a metabolic switch in response to FA. This study investigated the effects of FA on energy homeostasis in cultured human liver (HepG2) cells. HepG2 cells poised to undergo oxidative and glycolytic metabolism were exposed to a range of FA concentrations (4, 63 and 250 µg/mL) for 6 h. We determined mitochondrial toxicity, acetyl CoA levels and cell viability using luminometric, fluorometric and spectrophotometric methods. Expression of metabolic proteins (PDK1, PKM2, phosphorylated-PDH E1α and HIF-1α) and mRNAs (HIF-1α, PKM2, LDHa and PDK1) were determined using western blot and qPCR respectively. Our data connects a constitutive expression of HIF-1α in response to FA, to the inhibition of pyruvate decarboxylation through up-regulation of PDK-1 and phosphorylation of Pyruvate Dehydrogenase E1α subunit. Moreover, we highlight the potential of FA to induce a glucose "addiction" and phenotype reminiscent of the Warburg effect. The findings provide novel insights into the impact of this neglected foodborne mycotoxin in the dysregulation of energy metabolism.


Assuntos
Plasticidade Celular/efeitos dos fármacos , Microbiologia de Alimentos , Ácido Fusárico/toxicidade , Glicólise/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Fenótipo , Fosforilação , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Piruvato Desidrogenase (Lipoamida)/metabolismo
3.
J Agric Food Chem ; 67(46): 12844-12853, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31668063

RESUMO

Flazin is a ß-carboline-derived alkaloid found in Japanese fermented foods. Here, the potential of flazin as an antioxidant food was studied with particular reference to its effect on the Kelch-like ECH-associated protein 1 (Keap1)-nuclear factor erythroid 2-related factor 2 (Nrf2) system in human hepatocytes (C3A). Flazin and flazin analogues including the decarboxylated derivative perlolyrine were chemically synthesized and compared with each other and with chlorogenic acid and curcumin. Among these compounds, flazin showed the lowest cytotoxicity (IC50 < 500 µM) and the highest capacity to activate the Keap1-Nrf2 system. It provided the largest (>3-fold of the control) cytoprotection ability against a pro-oxidant, although its radical absorbance capacity was relatively low. Flazin increased the expressions of Nrf2-dependent phase II enzyme genes and their products (NQO1, GSTP, and GSH proteins). The strong cytoprotection ability of flazin associated with low log P (0-3) is shared by sulforaphane and 3,5-dihydroxy-4-methoxybenzyl alcohol, suggesting the potential value of flazin and flazin-rich foods for the prevention of oxidation-related health disorders.


Assuntos
Carbolinas/farmacologia , Furanos/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Proteína 1 Associada a ECH Semelhante a Kelch/genética , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/genética , Transdução de Sinais/efeitos dos fármacos
4.
Biochemistry (Mosc) ; 84(10): 1197-1203, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31694515

RESUMO

Here, we suggested that the epigenetic mechanism of benzo(a)pyrene (BP) action might be based on the aryl hydrocarbon receptor (AhR)-mediated transcription of the target genes, including miRNAs, that have the dioxin response element (DRE) in their promoters. The effect of BP on the expression of the oncogenic miR-483-3p, its host gene IGF2, and target gene IGF1 in primary hepatocytes and in the liver of Wistar female rats was investigated. The activation of AhR was confirmed using selective AhR inhibitor CH-223191 and by evaluating expression of the target CYP1A1 gene. The lack of coordination between the expression of miR-483-3p and its host gene IGF2 was revealed, which may be due to the presence of the binding site for the estrogen receptor alpha (ERα), which is a negative expression regulator. Our results confirm the existence of the AhR-mediated pathway in the regulation of expression of miR-483-3p, IGF1, and IGF2 under BP exposure, which is of considerable interest for understanding the epigenetic mechanisms of the carcinogenic effect of BP.


Assuntos
Benzo(a)pireno/farmacologia , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , MicroRNAs/antagonistas & inibidores , Animais , Células Cultivadas , Biologia Computacional , Feminino , Hepatócitos/metabolismo , Fígado/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Ratos , Ratos Wistar
5.
Nature ; 574(7779): 538-542, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31645727

RESUMO

The most common causes of chronic liver disease are excess alcohol intake, viral hepatitis and non-alcoholic fatty liver disease, with the clinical spectrum ranging in severity from hepatic inflammation to cirrhosis, liver failure or hepatocellular carcinoma (HCC). The genome of HCC exhibits diverse mutational signatures, resulting in recurrent mutations across more than 30 cancer genes1-7. Stem cells from normal livers have a low mutational burden and limited diversity of signatures8, which suggests that the complexity of HCC arises during the progression to chronic liver disease and subsequent malignant transformation. Here, by sequencing whole genomes of 482 microdissections of 100-500 hepatocytes from 5 normal and 9 cirrhotic livers, we show that cirrhotic liver has a higher mutational burden than normal liver. Although rare in normal hepatocytes, structural variants, including chromothripsis, were prominent in cirrhosis. Driver mutations, such as point mutations and structural variants, affected 1-5% of clones. Clonal expansions of millimetres in diameter occurred in cirrhosis, with clones sequestered by the bands of fibrosis that surround regenerative nodules. Some mutational signatures were universal and equally active in both non-malignant hepatocytes and HCCs; some were substantially more active in HCCs than chronic liver disease; and others-arising from exogenous exposures-were present in a subset of patients. The activity of exogenous signatures between adjacent cirrhotic nodules varied by up to tenfold within each patient, as a result of clone-specific and microenvironmental forces. Synchronous HCCs exhibited the same mutational signatures as background cirrhotic liver, but with higher burden. Somatic mutations chronicle the exposures, toxicity, regeneration and clonal structure of liver tissue as it progresses from health to disease.


Assuntos
Células Clonais/citologia , Células Clonais/patologia , Fibrose/genética , Fibrose/patologia , Fígado/citologia , Fígado/metabolismo , Mutação , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Células Clonais/metabolismo , Análise Mutacional de DNA , Hepatócitos/citologia , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Filogenia , Células-Tronco/citologia , Células-Tronco/metabolismo , Células-Tronco/patologia
6.
Expert Opin Drug Metab Toxicol ; 15(11): 975-984, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31619082

RESUMO

Objectives: Riociguat is a soluble guanylate cyclase stimulator licensed for the treatment of pulmonary arterial hypertension (PAH), a potentially fatal complication of human immunodeficiency virus infection. This study investigated the inhibitory potency of selected antiretroviral regimens on the metabolic clearance of riociguat.Methods: The inhibitory potential of the components of six antiretroviral combinations (ATRIPLA® (efavirenz/emtricitabine/tenofovir disoproxil), COMPLERA® (rilpivirine/emtricitabine/tenofovir disoproxil), STRIBILD® (elvitegravir/cobicistat/emtricitabine/tenofovir disoproxil), TRIUMEQ® (abacavir/dolutegravir/lamivudine), and two ritonavir-boosted regimens) on riociguat metabolism were evaluated in recombinant human CYP1A1 and CYP3A4 as well as in human hepatocytes exhibiting both CYP1A1 and CYP3A4 activity. In vitro-in vivo correlation was performed between calculated and observed increases in riociguat exposure in vivo.Results: Using both in vitro systems, the predicted increase in exposure of riociguat was highest with components of TRIUMEQ® followed by COMPLERA®, ATRIPLA®, STRIBILD®, and the ritonavir-boosted regimens. Further experiments in human hepatocytes confirmed CYP1A1 to be the predominant enzyme in the metabolic clearance of riociguat.Conclusion: Antiretroviral treatment containing the potent CYP1A1 inhibitor abacavir had the greatest impact on riociguat metabolic clearance. The impact of comedications containing only strong CYP3A4 inhibitors e.g. ritonavir was less pronounced, suggesting a benefit of riociguat over PAH-targeting medications with contraindications for use with strong CYP3A4 inhibitors.


Assuntos
Fármacos Anti-HIV/farmacologia , Citocromo P-450 CYP1A1/metabolismo , Ativadores de Enzimas/metabolismo , Pirazóis/metabolismo , Pirimidinas/metabolismo , Fármacos Anti-HIV/administração & dosagem , Citocromo P-450 CYP1A1/antagonistas & inibidores , Citocromo P-450 CYP3A/efeitos dos fármacos , Citocromo P-450 CYP3A/metabolismo , Inibidores do Citocromo P-450 CYP3A/administração & dosagem , Inibidores do Citocromo P-450 CYP3A/farmacologia , Interações de Medicamentos , Ativadores de Enzimas/administração & dosagem , Hepatócitos/enzimologia , Hepatócitos/metabolismo , Humanos , Técnicas In Vitro , Pirazóis/administração & dosagem , Pirimidinas/administração & dosagem
7.
Zhongguo Zhong Yao Za Zhi ; 44(17): 3780-3785, 2019 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-31602953

RESUMO

The aim of this paper was to investigate the molecular mechanism of Calculus Bovis Sativus( CBS) in alleviating lipid accumulation in vitro by serum pharmacology. The CBS-containing serum of mice was obtained by serum pharmacology method to evaluate its effect on the proliferation of LO2 hepatocytes. The lipid reducing effects of CBS-containing serum through Nrf2 was evaluated by fructose-induced LO2 hepatocyte steatosis model,nuclear factor erythroid 2 related factor 2( Nrf2) agonist oltipraz combined intervention,cell oil red O staining and intracellular triglyceride( TG) content. The effects of CBS-containing serum on lipid peroxidation and hepatocytes apoptosis were evaluated by reactive oxygen species( ROS) and apoptosis assay,respectively. Real-time quantitative polymerase chain reaction( PCR) was used to detect the relative expression of lipid synthesis-related genes and apoptosis-related genes.RESULTS:: showed that CBS drug-containing serum had no significant effect on LO2 hepatocyte proliferation. As compared with the model group,CBS-containing serum could effectively reduce the formation of lipid droplets in fructose-induced LO2 hepatocytes,significantly reduce intracellular TG and ROS levels,and significantly reduce hepatocyte apoptosis rate( P < 0. 05). As compared with the model group,carbohydrate responsive element binding protein( ChREBP),sterol regulatory element binding protein-1 c( SREBP-1 c),fatty acid synthase( FAS),acetyl-CoA carboxylase 1( ACC1),stearoyl-CoA desaturase 1( SCD1),Bax and caspase-3 mRNA levels were significantly reduced in CBS drug-containing serum treatment group( P<0. 05). All of the above effects could be reversed by oltipraz.In conclusion,CBS-containing serum can significantly inhibit the fructose-induced LO2 liver fat deposition,and the mechanism may be related to reducing intracellular ROS level through the Nrf2 pathway and improving intracellular peroxidation state to reduce apoptosis.


Assuntos
Cálculos Biliares/química , Hepatócitos/citologia , Soro/química , Animais , Apoptose , Bovinos , Células Cultivadas , Fígado Gorduroso , Frutose , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Peroxidação de Lipídeos , Fígado , Medicina Tradicional Chinesa , Camundongos , Espécies Reativas de Oxigênio/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos
8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 35(7): 606-612, 2019 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-31537245

RESUMO

Objective To investigate the effect of fibroblast growth factor 21 (FGF21) on the lipid accumulation and inflammation induced by palmitate treatment in L02 hepatocytes and the underlying mechanism. Methods L02 cells were infected with lentivirus expressing SIRT1 shRNA to knockdown SIRT1 expression. Wild-type and SIRT1-knockdown L02 cells were treated with 250 mol/L palmitate for 5 days, and then administrated with 1 g/ml FGF21 for 72 hours. Triglycerides in the cells were detected with the infinity triglycerides reagent. Malondialdehyde (MDA) in the cells was assessed by MDA detection assay. Tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6) levels in supernatant were measured by ELISA. Reactive oxygen species (ROS) levels were tested by the specific Amplex red ROS detection assay kit from Thermo Fisher Company. The gene expression of SIRT1, peroxisome proliferator-activated receptor γ coactivator 1α (PGC1α), superoxide dismutase 2 (SOD2) and catalase (CAT) were measured by real-time quantitative PCR. The protein levels of SIRT1, PGC1α, SOD2 and CAT were detected by Western blot analysis. Mitochondrial membrane potentials were detected by the JC-1staining kit. Mitochondrial oxygen consumption rate (OCR) was detected with the Seahorse XF Mito stress test kit. Results Palmitate increased the triglycerides level, induced the oxidative stress in both the cells and the mitochondria, decreased the gene expression and protein levels of SIRT1, PGC1α, SOD2 and CAT, increased the levels of TNF-α and IL-6, decreased the mitochondrial membrane potential, and impaired the mitochondrial function. FGF21 treatment could attenuate all of these effects caused by palmitate, while SIRT1 knockdown blocked most of the FGF21 effects on the L02 hepatocytes. Conclusion FGF21 activates SIRT1 pathway and inhibites the lipid accumulation, improves the mitochondrial function, and decreases the oxidative stress as well as inflammation in palmitate-treated L02 cells.


Assuntos
Fatores de Crescimento de Fibroblastos/metabolismo , Hepatócitos/metabolismo , Inflamação/metabolismo , Sirtuína 1/metabolismo , Catalase/metabolismo , Linhagem Celular , Hepatócitos/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , Estresse Oxidativo , Palmitatos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Superóxido Dismutase-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Int J Nanomedicine ; 14: 6451-6464, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31496697

RESUMO

Background: We recently reported on long-term comprehensive biocompatibility and biodistribution study of fluorescent nanodiamond particles (NV)-Z-average 800nm (FNDP-(NV)) in rats. FNDP-(NV) primary deposition was found in the liver, yet liver function tests remained normal. Purpose: The present study aimed to gain preliminary insights on discrete localization of FNDP-(NV) in liver cells of the hepatic lobule unit and venous micro-vasculature. Kinetics of FDNP-(NV) uptake into liver cells surrogates in culture was conducted along with cell cytokinesis as markers of cells' viability. Methods: Preserved liver specimens from a pilot consisting of two animals which were stained for cytoskeletal elements (fluorescein-isothiocyanate-phalloidin) were examined for distribution of FNDP-(NV) by fluorescent microscopy (FM) and Confocal-FM (CFM) using near infra-red fluorescence (NIR). Hepatocellular carcinoma cells (HepG-2) and human umbilical vein endothelial cells (HUVEC) were cultured with FNDP-(NV) and assayed for particle uptake and location using spectrophotometric technology and microscopy. Results: HepG-2 and HUVEC displayed rapid (<30 mins) onset and concentration-dependent FNDP-(NV) internalization and formation of peri-nuclear corona. FM/CFM of liver sections revealed FNDP-(NV) presence throughout the hepatic lobules structures marked by spatial distribution, venous microvascular spaces and parenchyma and non-parenchyma cells. Conclusion: The robust presence of FNDP-(NV) throughout the hepatic lobules including those internalized within parenchyma cells and agglomerates in the liver venous micro-circulation were not associated with macro or micro histopathological signs nor vascular lesions. Cells cultures indicated normal cytokinesis in cells containing FNDP-(NV) agglomerates. Liver parenchyma cells and the liver microcirculation remain agnostic to presence of FNDP-(NV) in the sinusoids or internalized in the hepatic cells.


Assuntos
Materiais Biocompatíveis/farmacologia , Fígado/metabolismo , Nanodiamantes/química , Animais , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/metabolismo , Humanos , Imagem Tridimensional , Cinética , Fígado/efeitos dos fármacos , Microscopia de Fluorescência , Tamanho da Partícula , Ratos Sprague-Dawley , Distribuição Tecidual
10.
Int J Nanomedicine ; 14: 6035-6060, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31534335

RESUMO

Background: The clearance of nanomaterials (NMs) from the liver is essential for clinical safety, and their hepatic clearance is primarily determined by the co-disposition process of various types of hepatic cells. Studies of this process and the subsequent clearance routes are urgently needed for organic NMs, which are used as drug carriers more commonly than the inorganic ones. Materials and methods: In this study, the co-disposition of chitosan-based nanoparticles (CsNps) by macrophages and hepatocytes at both the cellular and animal levels as well as their subsequent biological elimination were investigated. RAW264.7 and Hepa1-6 cells were used as models of Kupffer cells and hepatocytes, respectively. Results: The cellular studies showed that CsNps released from RAW264.7 cells could enter Hepa1-6 cells through both clathrin- and caveolin-mediated endocytosis. The transport from Kupffer cells to hepatocytes was also studied in mice, and it was observed that most CsNps localized to the hepatocytes after intravenous injection. Following the distribution in hepatocytes, the hepatobiliary-fecal excretion route was shown to be the primary elimination route for CsNps, besides the kidney-urinary excretion route. The elimination of CsNps in mice was a lengthy process, with a half time of about 2 months. Conclusion: The demonstration in this study of the transport of CsNps from macrophages to hepatocytes and the subsequent hepatobiliary-fecal excretion provides basic information for the future development and clinical application of NMs.


Assuntos
Quitosana/farmacologia , Hepatócitos/citologia , Hepatócitos/metabolismo , Nanopartículas/química , Animais , Transporte Biológico , Linhagem Celular Tumoral , Portadores de Fármacos/metabolismo , Exocitose , Hepatócitos/efeitos dos fármacos , Cinética , Fígado/metabolismo , Macrófagos/metabolismo , Camundongos , Nanopartículas/ultraestrutura , Fótons
11.
J Agric Food Chem ; 67(36): 10089-10096, 2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31423784

RESUMO

Circadian rhythms are closely associated with metabolic homeostasis. Metabolic disorders can be alleviated by many bioactive components through controlling of clock gene expressions. Capsaicin has been demonstrated with many beneficial effects including anti-obesity and anti-insulin resistance activities, yet whether the rhythmic expression of circadian clock genes are involved in the regulation of redox imbalance and glucose metabolism disorder by capsaicin remains unclear. In this work, the insulin resistance was induced in HepG2 cells by treatment of glucosamine. Glucose uptake levels, reactive oxygen species, H2O2 production, and mitochondrial membrane potential (MMP) were measured with/without capsaicin cotreatment. The mRNA and protein expressions of core circadian clock genes were evaluated by RT-qPCR and western blot analysis. Our study revealed that circadian misalignment could be ameliorated by capsaicin. The glucosamine-induced cellular redox imbalance and glucose metabolism disorder were ameliorated by capsaicin in a Bmal1-dependent manner.


Assuntos
Capsaicina/administração & dosagem , Relógios Circadianos/efeitos dos fármacos , Transtornos do Metabolismo de Glucose/tratamento farmacológico , Resistência à Insulina , Fatores de Transcrição ARNTL/genética , Fatores de Transcrição ARNTL/metabolismo , Animais , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/genética , Peptídeos e Proteínas de Sinalização do Ritmo Circadiano/metabolismo , Glucose/metabolismo , Transtornos do Metabolismo de Glucose/genética , Transtornos do Metabolismo de Glucose/metabolismo , Transtornos do Metabolismo de Glucose/fisiopatologia , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Insulinas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução/efeitos dos fármacos
12.
Aquat Toxicol ; 215: 105272, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31442592

RESUMO

A number of chemicals have been shown to affect epigenetic patterning and functions. Since epigenetic mechanisms regulate transcriptional networks, epigenetic changes induced by chemical exposure can represent early molecular events for long-term adverse physiological effects. Epigenetics has thus appeared as a research field of major interest within (eco)toxicological sciences. The present study aimed at measuring effects on epigenetic-related mechanisms of selected environmental chemicals (bisphenols, perfluorinated chemicals, methoxychlor, permethrin, vinclozolin and coumarin 47) in zebrafish embryos and liver cells (ZFL). Transcription of genes related to DNA methylation and histone modifications was measured and global DNA methylation was assessed in ZFL cells using the LUMA assay. The differences in results gathered from both models suggest that chemicals affect different mechanisms related to epigenetics in embryos and cells. In zebrafish embryos, exposure to bisphenol A, coumarin 47, methoxychlor and permethrin lead to significant transcriptional changes in epigenetic factors suggesting that they can impact early epigenome reprogramming related to embryonic development. In ZFL cells, significant transcriptional changes were observed upon exposure to all chemicals but coumarin 47; however, only perfluorooctane sulfonate induced significant effects on global DNA methylation. Notably, in contrast to the other tested chemicals, perfluorooctane sulfonate affected only the expression of the histone demethylase kdm5ba. In addition, kdm5ba appeared as a sensitive gene in zebrafish embryos as well. Taken together, the present results suggest a role for kdm5ba in regulating epigenetic patterns in response to chemical exposure, even though mechanisms remain unclear. To confirm these findings, further evidence is required regarding changes in site-specific histone marks and DNA methylation together with their long-term effects on physiological outcomes.


Assuntos
Embrião não Mamífero/metabolismo , Epigênese Genética , Fígado/metabolismo , Poluentes Químicos da Água/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/genética , Animais , Metilação de DNA/efeitos dos fármacos , Metilação de DNA/genética , Embrião não Mamífero/efeitos dos fármacos , Epigênese Genética/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Fígado/efeitos dos fármacos , Testes de Toxicidade Aguda , Transcrição Genética/efeitos dos fármacos
13.
J Agric Food Chem ; 67(35): 9934-9941, 2019 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-31402655

RESUMO

A fluorescence microscopic method for characterizing size, quantity, and oxidation of lipid droplets (LDs) in HepG2 cells was developed. LDs were induced by palmitic (PA), oleic (OA), or linoleic acids (LA) and stained with two fluorescent probes for neutral lipids and lipid peroxides. Each fatty acid increased the number of LDs and oxidized LDs (oxLDs) and the degree of LD oxidation time dependently, as well as increased intracellular triglyceride hydroperoxides. LDs induced by LA without 2,2'-azobis(2-amidinopropane)dihydrochloride (AAPH) showed the most significant oxidation degree over PA and OA, especially in large LDs (area ≥ 3 µm2, oxLD/LD = 52.3 ± 21.7%). Under this condition, two food-derived antioxidants were evaluated, and both of them significantly improved the LD characteristics. Moreover, chlorogenic acid reduced the quantity of large LDs by 74.0-87.6% in a dose-dependent manner. The proposed method provides a new approach to evaluate the effect of dietary antioxidants on LD characteristics.


Assuntos
Antioxidantes/metabolismo , Hepatócitos/química , Hepatócitos/metabolismo , Gotículas Lipídicas/metabolismo , Microscopia de Fluorescência/métodos , Antioxidantes/química , Ácido Clorogênico/química , Ácido Clorogênico/metabolismo , Fluorescência , Células Hep G2 , Humanos , Gotículas Lipídicas/química , Oxirredução
14.
Parasit Vectors ; 12(1): 388, 2019 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-31375125

RESUMO

BACKGROUND: Recent investigations indicate that schistosome infection is closely associated with aberrant glycolipid metabolism. However, the actual glycolipid metabolism gene expression, as well as the possible pathways that regulate glycolipid metabolism in the schistosome-infected liver, has not been extensively explored. METHODS: In this study, we evaluated the dynamic expression of glycolipid metabolism-associated genes and proteins in the livers from mice infected with Schistosoma japonicum at the indicated time points using real-time PCR and immunofluorescence. Then, cultures of macrophages were treated with schistosome soluble egg antigen (SEA) to detect the expression levels of genes associated with glucose and lipid metabolism in order to identify macrophages metabolic characteristics in response to these antigens. Furthermore, SEA-stimulated macrophages were co-cultures with hepatocytes and detected the effects of macrophages on the gene expression of hepatocytes metabolism. RESULTS: The expression of glycolysis-related genes (Ldha, Glut4, Pkm2, Glut1, Pfkfb3, Aldoc, HK2, Pfk) in the liver were upregulated but the gluconeogenesis gene (G6pc) was downregulated during S. japonicum infection. In addition, the mRNA levels of fatty acid (FA) oxidation-related genes (Ucp2, Atp5b, Pparg) in the liver were significantly upregulated; however, the FA synthesis genes (Fas, Acc, Scd1, Srebp1c) and lipid uptake gene (Cd36) were downregulated post-S. japonicum-infection. In consistence with these data, stimulation with SEA in vitro significantly enhanced the gene expression that involved in glycolysis and FA oxidation, but decreased genes related to gluconeogenesis, FA synthesis and lipid uptake in macrophages. The levels of phosphorylated AMPK, AKT and mTORC1 were increased in macrophages after SEA stimulation. Inhibition of phosphorylated AMPK, AKT and mTORC1 promoted SEA-treated macrophages to produce glucose. In addition, suppression of phosphorylated-AMPK, but not phosphorylated-AKT and phosphorylated-mTOR, induced the lipid accumulation in SEA-stimulated macrophages. Furthermore, SEA-treated macrophages significantly reduced the expression of Acc mRNA in hepatocytes in vitro. CONCLUSIONS: These findings reveal S. japonicum infection induces dynamic changes in the expression levels of genes involved in catabolism (glucose uptake, glycolysis and fatty acid oxidation) and suppressing anabolism (glycogen synthesis) in the liver, which could occur via macrophages' metabolic states, particularly those involved in the AMPK, AKT and mTORC1 pathways.


Assuntos
Glicolipídeos/metabolismo , Interações Hospedeiro-Parasita , Metabolismo dos Lipídeos/genética , Fígado/metabolismo , Fígado/parasitologia , Esquistossomose Japônica/genética , Animais , Antígenos de Helmintos/imunologia , Feminino , Expressão Gênica , Glucose/metabolismo , Hepatócitos/metabolismo , Hepatócitos/parasitologia , Macrófagos/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Schistosoma japonicum , Regulação para Cima
15.
Ecotoxicol Environ Saf ; 183: 109467, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31374384

RESUMO

Mancozeb (MZ) is a widely used ethylene-bis-dithiocarbamate fungicide in agriculture causing hepatoxic and genotoxic effects in rats. Curcumin (CUR) has various pharmacological effects including antioxidant and anti-inflammatory properties. This study investigated the efficacy of CUR in mitigating MZ-induced hepatotoxicity and genotoxicity in rats. Twenty-four male rats were divided into four equal groups; group I (control) was given carboxymethyl cellulose, group II was orally administered CUR (100 mg/kg b.wt), group III was gavaged with MZ (750 mg/kg b.wt), and group IV was co-treated with MZ and CUR at the same doses daily for 10 weeks. As a result, the concurrent treatment with CUR and MZ minimized the increased levels of liver function markers in serum, lipid peroxidation, pro-inflammatory mediators and DNA damage parameters in liver. In addition, CUR administration improved the depleted markers of hepatic antioxidant status in MZ-treated rats. Moreover, CUR protected the liver against the histological alterations elicited by MZ exposure and also, reduced the immunopositive reactivity of pro-apoptotic p53 in cytoplasm of hepatocytes. The present findings suggest that CUR exerts a significant protective effect against MZ-induced hepatotoxicity and genotoxicity.


Assuntos
Antioxidantes/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Curcumina/farmacologia , Dano ao DNA , Hepatócitos/efeitos dos fármacos , Maneb/toxicidade , Zineb/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Dano ao DNA/efeitos dos fármacos , Hepatócitos/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/genética , Masculino , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Ratos
16.
Ecotoxicol Environ Saf ; 183: 109465, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31376806

RESUMO

Our group found that long-term low-dose exposure to hexavalent chromium [Cr(VI)] in L-02 hepatocytes resulted in premature senescence, which accompanied by the increased expression of Clusterin (CLU), but the functional role of CLU in premature senescence has never been explored. In the present study, the CLU overexpressed or silenced L-02 hepatocytes were established by lentiviral vector transfection. Cell viability assay, cell cycle analysis, western blotting, plate clone formation assay, and confocal microcopy were performed. The results indicated that Cr(VI)-induced premature senescence was associated with phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT) pathway inhibition, and high expression of CLU in the senescent cells exerted its functional role of promoting cell proliferation. CLU could complex with eukaryotic translation initiation factor 3 subunit I (EIF3I) and prevent its degradation, leading to the increase of AKT activity in Cr(VI)-exposed senescent hepatocytes. Blockage of the PI3K/AKT pathway with its inhibitor LY294002 eliminated the inhibitory effect of CLU on Cr(VI)-induced premature senescence. We concluded that high expression of CLU suppressed Cr(VI)-induced premature senescence through activation of PI3K/AKT pathway, which will provide the experimental basis for the study of Cr(VI)-induced liver cancer, especially for the elucidation of the mechanism of liver cancer cells escaping from senescence.


Assuntos
Senescência Celular/efeitos dos fármacos , Cromo/toxicidade , Clusterina/genética , Hepatócitos/efeitos dos fármacos , Fosfatidilinositol 3-Quinase/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Senescência Celular/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
17.
Toxicol Lett ; 316: 183-193, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31437515

RESUMO

Olanzapine, a representative of antipsychotics, is a first-line drug for treatment of schizophrenia. However, olanzapine-induced liver steatosis limits its clinical utilization. This study is to explore the mechanism of liver steatosis induced by olanzapine based on the regulation of transporters involved in uptake and oxidation of fatty acids. Our results revealed that 12-week oral administration of olanzapine increased hepatic triglyceride(TG), caused liver steatosis. Our further studies showed that the expression of fatty acid transporter 2(FATP2) and fatty acid binding protein 1(FABP1) were up-regulated in liver of female mice after 12-week olanzapine exposure, as well as in primary mouse hepatocytes treated with olanzapine. Olanzapine treatment also reduced hepatic ß-hydroxybutyrate level (indicator of fatty acid ß-oxidation), meanwhile, the L-carnitine (L-Car) concentration in liver of olanzapine group was significantly lower than that in control group. Further study demonstrated that both mRNA and protein expression of hepatic OCTN2 (carnitine/organic cation transporter 2) were obviously down-regulated in male mice after 12-week olanzapine treatment. Also, olanzapine markedly inhibited L-Car uptake in MDCK-hOCTN2 cells (1.06 µM of IC50), HepG2 cells and primary mouse hepatocytes. Supplementation of L-Car attenuated hepatic TG rise and improved simple steatosis in olanzapine treatment mice. Taken together, up-regulation of FATP2/FABP1 and down-regulation/inhibition of hepatic OCTN2 probably contribute to olanzapine-induced liver steatosis. Supplementation of L-Car is a promising strategy to attenuate olanzapine-induced simple steatosis.


Assuntos
Antipsicóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Coenzima A Ligases/metabolismo , Proteínas de Ligação a Ácido Graxo/metabolismo , Fígado Gorduroso/induzido quimicamente , Hepatócitos/efeitos dos fármacos , Fígado/efeitos dos fármacos , Olanzapina/toxicidade , Membro 5 da Família 22 de Carreadores de Soluto/antagonistas & inibidores , Adulto , Animais , Carnitina/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Coenzima A Ligases/genética , Cães , Proteínas de Ligação a Ácido Graxo/genética , Fígado Gorduroso/metabolismo , Fígado Gorduroso/patologia , Fígado Gorduroso/prevenção & controle , Feminino , Células Hep G2 , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Células Madin Darby de Rim Canino , Masculino , Camundongos Endogâmicos C57BL , Membro 5 da Família 22 de Carreadores de Soluto/genética , Membro 5 da Família 22 de Carreadores de Soluto/metabolismo , Regulação para Cima
18.
Nucleic Acids Res ; 47(16): 8563-8580, 2019 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-31291457

RESUMO

Creating access to DNA double-strand break (DSB) sites in the chromatin context is an essential step during the repair process, but much remains to be determined about its regulatory mechanisms. Here, using a novel reporter cassette for simultaneous detection of homologous recombination (HR) and nonhomologous end joining (NHEJ) at the same chromosomal site, we report that the efficiency of HR but not NHEJ negatively correlates with nucleosome density. We demonstrate that PARP1 is required for HR by modulating nucleosome density at damage sites. Mechanistic studies indicate that the ATPase domain of BRG1 and the ZnF domain of SIRT1 interact with poly-ADP ribose (PAR) in response to DNA damage, and are responsible for bringing the two factors to broken DNA ends. At DNA damage sites, BRG1 and SIRT1 physically interact, whereupon SIRT1 deacetylates BRG1 at lysine residues 1029 and 1033, stimulating its ATPase activity to remodel chromatin and promote HR.


Assuntos
DNA Helicases/genética , DNA/genética , Proteínas Nucleares/genética , Nucleossomos/metabolismo , Poli(ADP-Ribose) Polimerase-1/genética , Reparo de DNA por Recombinação , Sirtuína 1/genética , Fatores de Transcrição/genética , Sítios de Ligação , Linhagem Celular , Linhagem Celular Tumoral , Cloroquina/farmacologia , DNA/metabolismo , Quebras de DNA de Cadeia Dupla , Reparo do DNA por Junção de Extremidades , DNA Helicases/metabolismo , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Células HEK293 , Hepatócitos/citologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Humanos , Proteínas Nucleares/metabolismo , Nucleossomos/química , Nucleossomos/efeitos dos fármacos , Fenantrenos/farmacologia , Ftalazinas/farmacologia , Piperazinas/farmacologia , Poli(ADP-Ribose) Polimerase-1/antagonistas & inibidores , Poli(ADP-Ribose) Polimerase-1/metabolismo , Poli Adenosina Difosfato Ribose/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Ligação Proteica , Domínios e Motivos de Interação entre Proteínas , Sirtuína 1/metabolismo , Fatores de Transcrição/metabolismo
19.
Nat Commun ; 10(1): 3051, 2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296864

RESUMO

Treatment of liver metastasis experiences slow progress owing to the severe side effects. In this study, we demonstrate a strategy capable of eliminating metastatic cancer cells in a selective manner. Nucleus-targeting W18O49 nanoparticles (WONPs) are conjugated to mitochondria-selective mesoporous silica nanoparticles (MSNs) containing photosensitizer (Ce6) through a Cathepsin B-cleavable peptide. In hepatocytes, upon the laser irradiation, the generated singlet oxygen species are consumed by WONPs, in turn leading to the loss of their photothermally heating capacity, thereby sparing hepatocyte from thermal damage induced by the laser illumination. By contrast, in cancer cells, the cleaved peptide linker allows WONPs and MSNs to respectively target nucleus and mitochondria, where the therapeutic powers could be unleashed, both photodynamically and photothermally. This ensures the energy production of cancer cells can be abolished. We further assess the underlying molecular mechanism at both gene and protein levels to better understand the therapeutic outcome.


Assuntos
Portadores de Fármacos/metabolismo , Neoplasias Hepáticas/terapia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Animais , Catepsina B/metabolismo , Núcleo Celular/metabolismo , Portadores de Fármacos/química , Feminino , Células HCT116 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Injeções Intravenosas , Lasers , Fígado/citologia , Fígado/metabolismo , Fígado/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/secundário , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mitocôndrias/metabolismo , Nanopartículas/química , Nanopartículas/metabolismo , Fosforilação Oxidativa , Óxidos/química , Fotoquimioterapia/instrumentação , Espécies Reativas de Oxigênio , Dióxido de Silício/química , Resultado do Tratamento , Tungstênio/química , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Chem Biol Interact ; 311: 108761, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31348918

RESUMO

Water contamination by cyanobacterial blooms is a worldwide health hazard to humans as well as livestock. Exposure to Microcystins (MCs), toxins produced by various cyanobacterial or blue green algae found in poorly treated drinking water or contaminated seafood such as fish or prawns are associated with hepatotoxicity, nephropathy and neurotoxicity and in extreme cases, death in humans. MC congeners, currently >240 known, differ dramatically in their uptake kinetics, i.e. their uptake via OATP1B1 and OATP1B3, in OATP overexpressing human HEK293 cells and primary human hepatocytes. It is thus likely that MC congeners will also differ with respect to the cellular efflux of the parent and conjugated congeners, e.g. via MRPs, MDRs, BCRP or BSEP. Consequently, the role and kinetics of different human efflux transporters - MRP, MDR, BCRP and BSEP in MC efflux was studied using insect membrane vesicles overexpressing the human transporters of interest. Of the efflux transporters investigated, MRP2 displayed MC transport. Michaelis-Menten kinetics displayed mild co-operativity and thus allosteric behavior of MRP2. MC transport by MRP2 was MC congener-specific, whereby MC-LF was transported more rapidly than MC-LR and -RR. Other human transporters (BCRP, BSEP, MRP1,3,5, MDR1) tested in this study did not exhibit interaction with MC. Although MRP2 showed specific MC transport, the MC-LR-GSH conjugate, was not transported suggesting the involvement of other transporters than MRP2 for the conjugate efflux.


Assuntos
Glutationa/química , Microcistinas/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP/metabolismo , Benzobromarona/química , Benzobromarona/metabolismo , Cromatografia Líquida de Alta Pressão , Células HEK293 , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Microcistinas/análise , Proteínas Associadas à Resistência a Múltiplos Medicamentos/antagonistas & inibidores , Transportadores de Ânions Orgânicos/genética , Transportadores de Ânions Orgânicos/metabolismo , Espectrometria de Massas em Tandem
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