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OBJECTIVE: The study was designed to examine the effects of simultaneous combination of aerobic exercise and video game training on executive functions (EFs) and brain functional connectivity in older adults. DESIGN: A four-armed, quasi-experimental study. SETTING AND PARTICIPANTS: Community-dwelling adults aged 55 years and older. METHODS: A total of 97 older adults were divided into one of four groups: aerobic exercise (AE), video game (VG), combined intervention (CI), and passive control (PC). Participants in intervention groups received 32 sessions of training over a 4-month period at a frequency of twice a week. EFs was evaluated using a composite score derived from a battery of neuropsychological tests. The Montreal Cognitive Assessment (MoCA) was employed to evaluate overall cognitive function, while the 6-Minute Walking Test (6MWT) was utilized to gauge physical function. Additionally, the functional connectivity (FC) of the frontal-parietal networks (FPN) was examined as a neural indicator of cognitive processing and connectivity changes. RESULTS: In terms of EFs, both VG and CI groups demonstrated improvement following the intervention. This improvement was particularly pronounced in the CI group, with a large effect size (Hedge's g = 0.83), while the VG group showed a medium effect size (Hedge's g = 0.56). A significant increase in MoCA scores was also observed in both the VG and CI groups, whereas a significant increase in 6MWT scores was observed in the AE and CI groups. Although there were no group-level changes observed in FC of the FPN, we found that changes in FC was behaviorally relevant as increased FC was associated with greater improvement in EFs. CONCLUSION: The study offers preliminary evidence that both video game training and combined intervention could enhance EFs in older adults. Simultaneous combined intervention may hold greater potential for facilitating EFs gains. The initial evidence for correlated changes in brain connectivity and EFs provides new insights into understanding the neural basis underlying the training gains.
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Deltamethrin (DM) is a widely used insecticide that has demonstrated developmental toxicity in the early life stages of fish. To better characterize the underlying mechanisms, embryos from Tg(cmlc2:RFP), Tg(apo14:GFP), and Tg(mpx:GFP) transgenic strains of zebrafish were exposed to nominal DM concentrations of 0.1, 1, 10, 25, and 50 µg/L until 120 h post-fertilization (hpf). Heart size increased 56.7%, and liver size was reduced by 17.1% in zebrafish exposed to 22.7 and 24.2 µg/L DM, respectively. RNA sequencing and bioinformatic analyses predicted that key biological processes affected by DM exposure were related to inflammatory responses. Expression of IL-1 protein was increased by 69.0% in the 24.4 µg/L DM treatment, and aggregation of neutrophils in cardiac and hepatic histologic sections was also observed. Coexposure to resatorvid, an anti-inflammatory agent, mitigated inflammatory responses and cardiac toxicity induced by DM and also restored liver biomass. Our data indicated a complex proinflammatory mechanism underlying DM-induced cardiotoxicity and hepatotoxicity which may be important for key events of adverse outcomes and associated risks of DM to early life stages of fish.
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Cardiotoxicidad , Pez Cebra , Animales , Piretrinas/toxicidad , Insecticidas/toxicidad , Hígado/efectos de los fármacos , Nitrilos/toxicidad , Corazón/efectos de los fármacosRESUMEN
Cell cycle transitions are controlled by multiple cell cycle regulators, especially CDKs. Several CDKs, including CDK1-4 and CDK6, promote cell cycle progression directly. Among them, CDK3 is critically important because it triggers the transitions of G0 to G1 and G1 to S phase through binding to cyclin C and cyclin E1, respectively. In contrast to its highly related homologs, the molecular basis of CDK3 activation remains elusive due to the lack of structural information of CDK3, particularly in cyclin bound form. Here we report the crystal structure of CDK3 in complex with cyclin E1 at 2.25 Å resolution. CDK3 resembles CDK2 in that both adopt a similar fold and bind cyclin E1 in a similar way. The structural discrepancy between CDK3 and CDK2 may reflect their substrate specificity. Profiling a panel of CDK inhibitors reveals that dinaciclib inhibits CDK3-cyclin E1 potently and specifically. The structure of CDK3-cyclin E1 bound to dinaciclib reveals the inhibitory mechanism. The structural and biochemical results uncover the mechanism of CDK3 activation by cyclin E1 and lays a foundation for structural-based drug design.
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Indolizinas , Proteínas Serina-Treonina Quinasas , Proteínas Serina-Treonina Quinasas/metabolismo , Quinasa 2 Dependiente de la Ciclina , Indolizinas/farmacología , Compuestos de Piridinio/farmacología , Ciclo Celular/fisiología , Ciclina E/metabolismo , Ciclinas/metabolismoRESUMEN
Tebuconazole is a widely used fungicide for various crops that targets sterol 14-α-demethylase (CYP51) in fungi. However, attention has shifted to aromatase (CYP19) due to limited research indicating its reproductive impact on aquatic organisms. Herein, zebrafish were exposed to 0.5 mg/L tebuconazole at different developmental stages. The proportion of males increased significantly after long-term exposure during the sex differentiation phase (0-60, 5-60, and 19-60 days postfertilization (dpf)). Testosterone levels increased and 17ß-estradiol and cyp19a1a expression levels decreased during the 5-60 dpf exposure, while the sex ratio was equally distributed on coexposure with 50 ng/L 17ß-estradiol. Chemically activated luciferase gene expression bioassays determined that the male-biased sex differentiation was not caused by tebuconazole directly binding to sex hormone receptors. Protein expression and phosphorylation levels were specifically altered in the vascular endothelial growth factor signaling pathway despite excluding the possibility of tebuconazole directly interacting with kinases. Aromatase was selected for potential target analysis. Molecular docking and aromatase activity assays demonstrated the interactions between tebuconazole and aromatase, highlighting that tebuconazole poses a threat to fish populations by inducing a gender imbalance.
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Diferenciación Sexual , Pez Cebra , Masculino , Animales , Diferenciación Sexual/genética , Aromatasa/genética , Aromatasa/metabolismo , Larva/metabolismo , Simulación del Acoplamiento Molecular , Factor A de Crecimiento Endotelial Vascular/metabolismo , Estradiol/metabolismoRESUMEN
The extensively studied cAMP-dependent protein kinase A (PKA) is involved in the regulation of critical cell processes, including metabolism, gene expression, and cell proliferation. Therefore, PKA has been viewed increasingly as potential target for variety of drugs and environmental endocrine disruptors. Consequentially, the preparation of PKA protein became an important initial step for the subsequent exploration of PKA's character in endocrine disrupting effects of pesticides. To investigate PKA protein, which is potential to be the environmental endocrine toxicity target of triazole fungicides, a strategy to heterologously express protein kinase A catalytic alpha subunit of human (hPKAcα) and zebrafish (zPKAcα) in Escherichia coli (E. coli) BL21(DE3) host cells was demonstrated. After optimizing conditions and protein purification, we successfully obtained enzymatically active hPKAcα and zPKAcα. Western blot analysis indicated that the recombinant hPKAcα and zPKAcα still retained their characteristic antigenicity and binding activity, while in vitro kinase activity assays revealed that the recombinant hPKAcα and zPKAcα maintained enzyme activity. By in silico methods including homology modelling and molecular docking, the affinity of ligands and the models of hPKAcα and zPKAcα were further tested. The present study offered a valuable method to achieve the prokaryotic expression of a eukaryotic protein kinase and laid a foundation to facilitate further investigation of toxicological target of triazole pesticides.
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The pyruvate dehydrogenase complex (PDC) is a key control point of energy metabolism and is subject to regulation by multiple mechanisms, including posttranslational phosphorylation by pyruvate dehydrogenase kinase (PDK). Pharmacological modulation of PDC activity could provide a new treatment for diabetic cardiomyopathy, as dysregulated substrate selection is concomitant with decreased heart function. Dichloroacetate (DCA), a classic PDK inhibitor, has been used to treat diabetic cardiomyopathy, but the lack of specificity and side effects of DCA indicate a more specific inhibitor of PDK is needed. This study was designed to determine the effects of a novel and highly selective PDK inhibitor, 2((2,4-dihydroxyphenyl)sulfonyl) isoindoline-4,6-diol (designated PS10), on pyruvate oxidation in diet-induced obese (DIO) mouse hearts compared with DCA-treated hearts. Four groups of mice were studied: lean control, DIO, DIO + DCA, and DIO + PS10. Both DCA and PS10 improved glucose tolerance in the intact animal. Pyruvate metabolism was studied in perfused hearts supplied with physiological mixtures of long chain fatty acids, lactate, and pyruvate. Analysis was performed using conventional 1H and 13C isotopomer methods in combination with hyperpolarized [1-13C]pyruvate in the same hearts. PS10 and DCA both stimulated flux through PDC as measured by the appearance of hyperpolarized [13C]bicarbonate. DCA but not PS10 increased hyperpolarized [1-13C]lactate production. Total carbohydrate oxidation was reduced in DIO mouse hearts but increased by DCA and PS10, the latter doing so without increasing lactate production. The present results suggest that PS10 is a more suitable PDK inhibitor for treatment of diabetic cardiomyopathy.
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Carbohidratos/química , Dieta/efectos adversos , Corazón/fisiología , Obesidad/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Ácido Pirúvico/metabolismo , Animales , Metabolismo Energético , Corazón/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Obesos , Obesidad/tratamiento farmacológico , Obesidad/etiología , Obesidad/patología , Oxidación-Reducción , Inhibidores de Proteínas Quinasas/química , Piruvato Deshidrogenasa Quinasa Acetil-Transferidora , Complejo Piruvato Deshidrogenasa/antagonistas & inhibidoresRESUMEN
Evidence has demonstrated that sleep-related memory consolidation declines in ageing. However, little is known about age-related changes to sleep-related emotional memory consolidation, especially when considering the positivity effect observed in older adults. In the present study, we sought to explore whether there is a positive emotional bias in sleep-related memory consolidation among healthy older adults. Young and older adults were randomly assigned either into a sleep or wake condition. All participants encoded positive, negative, and neutral stimuli and underwent recognition tests immediately (test 1), after a 12-hour sleep/wake interval (test 2), and 3 days after test 2 (test 3). Results showed that age-related differences of sleep beneficial effect were modulated by emotion valence. In particular, sleep selectively enhanced positive memory in older adults, while in young adults sleep beneficial effect was manifested in neutral memory. Moreover, the sleep beneficial effect can be maintained at least 3 days in both young and older adults. These findings suggest that older adults had preserved but positive bias of sleep-related memory consolidation, which could be one of the underlying mechanisms for their generally better emotional well-being in daily life. These findings highlight the dynamic interplay among sleep and emotional memory in older adults.
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Envejecimiento , Emociones , Consolidación de la Memoria/fisiología , Sueño/fisiología , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reconocimiento en Psicología , Adulto JovenRESUMEN
BACKGROUND: Although metabolic reprogramming is critical in the pathogenesis of heart failure, studies to date have focused principally on fatty acid and glucose metabolism. Contribution of amino acid metabolic regulation in the disease remains understudied. METHODS AND RESULTS: Transcriptomic and metabolomic analyses were performed in mouse failing heart induced by pressure overload. Suppression of branched-chain amino acid (BCAA) catabolic gene expression along with concomitant tissue accumulation of branched-chain α-keto acids was identified as a significant signature of metabolic reprogramming in mouse failing hearts and validated to be shared in human cardiomyopathy hearts. Molecular and genetic evidence identified the transcription factor Krüppel-like factor 15 as a key upstream regulator of the BCAA catabolic regulation in the heart. Studies using a genetic mouse model revealed that BCAA catabolic defect promoted heart failure associated with induced oxidative stress and metabolic disturbance in response to mechanical overload. Mechanistically, elevated branched-chain α-keto acids directly suppressed respiration and induced superoxide production in isolated mitochondria. Finally, pharmacological enhancement of branched-chain α-keto acid dehydrogenase activity significantly blunted cardiac dysfunction after pressure overload. CONCLUSIONS: BCAA catabolic defect is a metabolic hallmark of failing heart resulting from Krüppel-like factor 15-mediated transcriptional reprogramming. BCAA catabolic defect imposes a previously unappreciated significant contribution to heart failure.
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Aminoácidos de Cadena Ramificada/genética , Aminoácidos de Cadena Ramificada/metabolismo , Insuficiencia Cardíaca/genética , Insuficiencia Cardíaca/metabolismo , Animales , Insuficiencia Cardíaca/patología , Humanos , Masculino , Metabolismo/fisiología , Metabolómica , Ratones , Ratones Noqueados , TranscriptomaRESUMEN
The herbicide acetochlor is widely used and detected in the environment and biota, and has been suspected to disrupt the thyroid endocrine system, but underlying mechanisms have not yet been clarified. In the present study, zebrafish larvae (7 days post-fertilization) were exposed to a series concentration of acetochlor (0, 1, 3, 10, 30, 100 and 300 µg l(-1) ) within a 14-day window until 21 days post-fertilization. Thyroid hormones and mRNA expression profiles of genes involved in the hypothalamic-pituitary-thyroid (HPT) axis were analyzed. Exposure to the positive control, 3,5,3'-triiodothyronine (T3 ), altered the mRNA expression, suggesting that the HPT axis in the critical window of zebrafish responded to chemical exposure and could be used to evaluate the effects of chemicals on the thyroid endocrine system. The mRNA expressions of genes involved in thyroid hormone synthesis (tshß, slc5a5 and tpo) were upregulated significantly with acetochlor treatment, which might be responsible for the increased thyroxine concentrations. The downregulation of genes related to thyroid hormone metabolism (dio1 and ugt1ab) and transport (ttr) in zebrafish larvae exposed to acetochlor might further explain the increased thyroxine levels and decreased T3 levels. The mRNA expression of the thyroid hormone receptor (trα) was also upregulated upon acetochlor exposure. Results suggested that acetochlor altered mRNA expression of the HPT axis-related genes and changed the whole body thyroid hormone levels in zebrafish larvae. It demonstrated that acetochlor could cause endocrine disruption of the thyroid system by simulating the biological activity of T3 . Copyright © 2015 John Wiley & Sons, Ltd.
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Disruptores Endocrinos/toxicidad , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Herbicidas/toxicidad , Larva/efectos de los fármacos , Glándula Tiroides/efectos de los fármacos , Toluidinas/toxicidad , Pez Cebra , Animales , Glucuronosiltransferasa/antagonistas & inhibidores , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Sistema Hipotálamo-Hipofisario/efectos de los fármacos , Sistema Hipotálamo-Hipofisario/crecimiento & desarrollo , Sistema Hipotálamo-Hipofisario/metabolismo , Yoduro Peroxidasa/antagonistas & inhibidores , Yoduro Peroxidasa/química , Yoduro Peroxidasa/genética , Yoduro Peroxidasa/metabolismo , Larva/crecimiento & desarrollo , Larva/metabolismo , Dosificación Letal Mediana , Concentración Osmolar , Sistema Hipófiso-Suprarrenal/efectos de los fármacos , Sistema Hipófiso-Suprarrenal/crecimiento & desarrollo , Sistema Hipófiso-Suprarrenal/metabolismo , ARN Mensajero/metabolismo , Distribución Aleatoria , Simportadores/agonistas , Simportadores/genética , Simportadores/metabolismo , Tirotropina de Subunidad beta/agonistas , Tirotropina de Subunidad beta/genética , Tirotropina de Subunidad beta/metabolismo , Pez Cebra/crecimiento & desarrollo , Pez Cebra/metabolismo , Proteínas de Pez Cebra/agonistas , Proteínas de Pez Cebra/antagonistas & inhibidores , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismoRESUMEN
The branched-chain amino acids (BCAAs) leucine, isoleucine, and valine are elevated in maple syrup urine disease, heart failure, obesity, and type 2 diabetes. BCAA homeostasis is controlled by the mitochondrial branched-chain α-ketoacid dehydrogenase complex (BCKDC), which is negatively regulated by the specific BCKD kinase (BDK). Here, we used structure-based design to develop a BDK inhibitor, (S)-α-chloro-phenylpropionic acid [(S)-CPP]. Crystal structures of the BDK-(S)-CPP complex show that (S)-CPP binds to a unique allosteric site in the N-terminal domain, triggering helix movements in BDK. These conformational changes are communicated to the lipoyl-binding pocket, which nullifies BDK activity by blocking its binding to the BCKDC core. Administration of (S)-CPP to mice leads to the full activation and dephosphorylation of BCKDC with significant reduction in plasma BCAA concentrations. The results buttress the concept of targeting mitochondrial BDK as a pharmacological approach to mitigate BCAA accumulation in metabolic diseases and heart failure.
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Proteínas Mitocondriales/química , Inhibidores de Proteínas Quinasas/química , Proteínas Quinasas/química , Estructura Terciaria de Proteína , Regulación Alostérica , Animales , Sitios de Unión/genética , Cromatografía Liquida , Cristalografía por Rayos X , Isoleucina/sangre , Isoleucina/metabolismo , Cinética , Leucina/sangre , Leucina/metabolismo , Masculino , Ratones , Ratones Endogámicos ICR , Proteínas Mitocondriales/antagonistas & inhibidores , Proteínas Mitocondriales/metabolismo , Modelos Moleculares , Estructura Molecular , Mutación , Fenilpropionatos/química , Fenilpropionatos/metabolismo , Fenilpropionatos/farmacología , Fosforilación , Unión Proteica , Inhibidores de Proteínas Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Quinasas/metabolismo , Espectrometría de Masas en Tándem , Valina/sangre , Valina/metabolismoRESUMEN
Pyruvate dehydrogenase kinase isoforms (PDKs 1-4) negatively regulate activity of the mitochondrial pyruvate dehydrogenase complex by reversible phosphorylation. PDK isoforms are up-regulated in obesity, diabetes, heart failure, and cancer and are potential therapeutic targets for these important human diseases. Here, we employed a structure-guided design to convert a known Hsp90 inhibitor to a series of highly specific PDK inhibitors, based on structural conservation in the ATP-binding pocket. The key step involved the substitution of a carbonyl group in the parent compound with a sulfonyl in the PDK inhibitors. The final compound of this series, 2-[(2,4-dihydroxyphenyl)sulfonyl]isoindoline-4,6-diol, designated PS10, inhibits all four PDK isoforms with IC50 = 0.8 µM for PDK2. The administration of PS10 (70 mg/kg) to diet-induced obese mice significantly augments pyruvate dehydrogenase complex activity with reduced phosphorylation in different tissues. Prolonged PS10 treatments result in improved glucose tolerance and notably lessened hepatic steatosis in the mouse model. The results support the pharmacological approach of targeting PDK to control both glucose and fat levels in obesity and type 2 diabetes.
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Diabetes Mellitus Tipo 2/tratamiento farmacológico , Inhibidores Enzimáticos , Hígado Graso/tratamiento farmacológico , Isoindoles/química , Isoindoles/farmacología , Obesidad/tratamiento farmacológico , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Sulfonas/química , Sulfonas/farmacología , Animales , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patología , Sistemas de Liberación de Medicamentos , Diseño de Fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Hígado Graso/enzimología , Hígado Graso/genética , Hígado Graso/patología , Proteínas HSP90 de Choque Térmico , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Ratones , Ratones Obesos , Obesidad/enzimología , Obesidad/genética , Obesidad/patología , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Piruvato Deshidrogenasa Quinasa Acetil-TransferidoraRESUMEN
The mitochondrial branched-chain α-ketoacid dehydrogenase complex (BCKDC) is negatively regulated by reversible phosphorylation.BCKDC kinase (BDK) inhibitors that augment BCKDC flux have been shown to reduce branched-chain amino acid (BCAA) concentrations in vivo. In the present study, we employed high-throughput screens to identify compound 3,6- dichlorobenzo[b]thiophene-2-carboxylic acid (BT2) as a novel BDK inhibitor (IC(50) = 3.19 µM). BT2 binds to the same site in BDK as other known allosteric BDK inhibitors, including (S)-α-cholorophenylproprionate ((S)-CPP). BT2 binding to BDK triggers helix movements in the N-terminal domain, resulting in the dissociation of BDK from the BCKDC accompanied by accelerated degradation of the released kinase in vivo. BT2 shows excellent pharmacokinetics (terminal T(1/2) = 730 min) and metabolic stability (no degradation in 240 min), which are significantly better than those of (S)-CPP. BT2, its analog 3-chloro-6-fluorobenzo[ b]thiophene-2-carboxylic acid (BT2F), and a prodrug of BT2 (i.e. N-(4-acetamido-1,2,5-oxadiazol-3-yl)-3,6-dichlorobenzo[ b]thiophene-2-carboxamide (BT3)) significantly increase residual BCKDC activity in cultured cells and primary hepatocytes from patients and a mouse model of maple syrup urine disease. Administration of BT2 at 20 mg/kg/day to wild-type mice for 1 week leads to nearly complete dephosphorylation and maximal activation of BCKDC in heart, muscle, kidneys, and liver with reduction in plasma BCAA concentrations. The availability of benzothiophene carboxylate derivatives as stable BDK inhibitors may prove useful for the treatment of metabolic disease caused by elevated BCAA concentrations.
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Inhibidores Enzimáticos/farmacología , Hepatocitos/enzimología , Complejo Cetoglutarato Deshidrogenasa/antagonistas & inhibidores , Complejo Cetoglutarato Deshidrogenasa/metabolismo , Proteolisis/efectos de los fármacos , Tiofenos/farmacología , Regulación Alostérica/efectos de los fármacos , Animales , Línea Celular , Relación Dosis-Respuesta a Droga , Estabilidad de Enzimas/efectos de los fármacos , Estabilidad de Enzimas/genética , Hepatocitos/patología , Humanos , Complejo Cetoglutarato Deshidrogenasa/genética , Ratones , Ratones Noqueados , Tiofenos/farmacocinéticaRESUMEN
The death receptors Fas, p75(NTR) and DR6 are key components of extrinsically activated apoptosis. Characterization of how they interact with the adaptors is crucial in order to unravel the signalling mechanisms. However, the exact conformation that their intracellular death domain adopts upon binding downstream partners remains unclear. One model suggests that it adopts a typical compact fold, whilst a second model proposed an open conformation. Calmodulin (CaM), a major calcium sensor, has previously been reported to be one of the Fas adaptors that modulate apoptosis. This work reports that CaM also binds directly to the death domains of p75(NTR) and DR6, indicating that it serves as a common modulator of the death receptors. Two crystal structures of CaM in complexes with the corresponding binding regions of Fas and p75(NTR) are also reported. Interestingly, the precise CaM-binding sites were mapped to different regions: helix 1 in Fas and helix 5 in p75(NTR) and DR6. A novel 1-11 motif for CaM binding was observed in p75(NTR). Modelling the complexes of CaM with full-length receptors reveals that the opening of the death domains would be essential in order to expose their binding sites for CaM. These results may facilitate understanding of the diverse functional repertoire of death receptors and CaM and provide further insights necessary for the design of potential therapeutic peptide agents.
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Calmodulina/metabolismo , Receptores de Muerte Celular/metabolismo , Secuencia de Aminoácidos , Animales , Sitios de Unión , Cristalografía por Rayos X , Modelos Moleculares , Datos de Secuencia Molecular , Células PC12 , Conformación Proteica , Ratas , Receptores de Muerte Celular/química , Homología de Secuencia de Aminoácido , Resonancia por Plasmón de SuperficieRESUMEN
Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC) worldwide. The pre-S2 mutant large HBV surface protein (Δ2 LHBS), which contains an in-frame deletion of approximately 17 amino acids in LHBS, is highly associated with risks and prognoses of HBV-induced HCC. It was previously reported that Δ2 LHBS interacts with the Jun activation domain-binding protein 1 (JAB1), a zinc metalloprotease. This promotes the degradation of the cell cycle regulator p27(Kip1) and is believed to be the major mechanism for Δ2 LHBS-induced HCC. In this study, it was found that the interaction between JAB1 and Δ2 LHBS is facilitated by divalent metal Zn(2+) ions. The binding of JAB1 to Δ2 LHBS requires the JAB1/CSN5 MPN metalloenzyme (JAMM) motif and residue H138 that binds to Zn(2+) ions in JAB1. Isothermal titration calorimetry showed that Δ2 LHBS binds directly to Zn(2+) ions in a two-site binding mode. Residues H71 and H116 in Δ2 LHBS, which also contact Zn(2+) ions, are also indispensable for Δ2 LHBS-mediated p27(Kip1) degradation in human HuH7 cells. These results suggest that developing drugs that interrupt interactions between Δ2 LHBS and JAB1 can be used to mitigate Δ2 LHBS-associated risks for HCC.
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Carcinoma Hepatocelular/enzimología , Antígenos de Superficie de la Hepatitis B/metabolismo , Virus de la Hepatitis B/metabolismo , Hepatitis B Crónica/enzimología , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Neoplasias Hepáticas/enzimología , Péptido Hidrolasas/metabolismo , Precursores de Proteínas/metabolismo , Zinc/metabolismo , Secuencias de Aminoácidos , Complejo del Señalosoma COP9 , Carcinoma Hepatocelular/virología , Línea Celular Tumoral , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/genética , Neoplasias Hepáticas/virología , Péptido Hidrolasas/química , Péptido Hidrolasas/genética , Unión Proteica , Precursores de Proteínas/genéticaRESUMEN
Saflufenacil is a new protoporphyrinogen-IX-oxidase inhibitor herbicide. When used, it can enter the soil and has a high risk to reach and contaminate groundwater and aquatic systems. A rapid and sensitive method of ultra-performance LC with MS/MS was developed for the simultaneous determination of saflufenacil and its two metabolites in soil samples. A modified quick, easy, cheap, effective, rugged, and safe method was applied as the pretreatment procedure. The method was validated by five types of soil samples collected from several regions of China, which all showed good linearity (R(2) ≥ 0.9914) and precision (RSD ≤ 26.2%). The average recoveries of the three analytes ranged between 74.1 and 118.9% at spiking levels of 3-300 µg/kg. The method limits of detection (S/N 3:1) and method limits of quantification (S/N 10:1) achieved are in the ranges of 0.25-2.75 and 0.83-9.16 µg/kg, respectively. This indicated that the developed ultra-performance LC with MS/MS method is a promising analytical tool for monitoring the environmental risks posed by saflufenacil.
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Pirimidinonas/análisis , Pirimidinonas/metabolismo , Suelo/química , Sulfonamidas/análisis , Sulfonamidas/metabolismo , Cromatografía Líquida de Alta Presión , Contaminantes del Suelo/análisis , Contaminantes del Suelo/química , Contaminantes del Suelo/metabolismo , Espectrometría de Masas en TándemRESUMEN
Tebuconazole (TEB) is a commonly used fungicide that inhibits the aromatase Cyp19A and downregulates the transcription factor forkhead box L2 (FoxL2), leading to male-biased sex differentiation in zebrafish larvae. However, the specific mechanism by which FoxL2 functions following TEB exposure remains unclear. In this study, the phosphorylation sites and kinase-specific residues in zebrafish FoxL2 protein (zFoxL2) were predicted. Subsequently, recombinant zFoxL2 was prepared via prokaryotic expression, and a polyclonal rabbit-anti-zFoxL2 antibody was generated. Zebrafish fibroblast (ZF4) cells were exposed to 100-µM TEB alone for 8 h, after which changes in the expression of genes involved in the foxl2 regulatory pathway (akt1, pi3k, cyp19a1b, c/ebpb and sox9a) were detected. When co-exposed to 1-µM estradiol and 100-µM TEB, the expression of these key genes tended to be restored. Interestingly, TEB did not affect the expression of the foxl2 gene or protein but it significantly suppressed the phosphorylation of FoxL2 (pFoxL2) at serine 238 (decreased by 43.64 %, p = 0.009). Co-immunoprecipitation assays showed that, following exposure to 100-µM TEB, the total precipitated proteins in ZF4 cells decreased by 17.02 % (p = 0.029) and 31.39 % (p = 0.027) in the anti-zFoxL2 antibody group and anti-pFoxL2 (ser238) antibody group, respectively, indicating that TEB suppressed the capacity of the FoxL2 protein to bind to other proteins via repression of its own phosphorylation. The pull-down assay confirmed this conclusion. This study preliminarily elucidated that the foxl2 gene functions via post-translational regulation through hypophosphorylation of its encoded protein during TEB-induced male-biased sex differentiation.
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Proteína Forkhead Box L2 , Fungicidas Industriales , Diferenciación Sexual , Triazoles , Pez Cebra , Animales , Diferenciación Sexual/efectos de los fármacos , Triazoles/toxicidad , Proteína Forkhead Box L2/genética , Masculino , Fungicidas Industriales/toxicidad , Proteínas de Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Contaminantes Químicos del Agua/toxicidad , FemeninoRESUMEN
Deltamethrin is a classical pyrethroid insecticide that is frequently detected in aquatic environments and organisms. Furthermore, deltamethrin has been detected in samples related to human health and is a potential risk to public health. This study aimed to investigate the mechanism of cardiotoxicity induced by deltamethrin. Zebrafish were exposed to 0.005, 0.05, or 0.5 µg/L deltamethrin for 28 days. The results showed a significant reduction in male reproduction compared to female reproduction. Additionally, the heart rate decreased by 15.75 % in F1 after parental exposure to 0.5 µg/L deltamethrin. To evaluate cardiotoxicity, deltamethrin was administered to the zebrafish embryos. By using miRNA-Seq and bioinformatics analysis, it was discovered that miR-29b functions as a toxic regulator by targeting dnmts. The overexpression of miR-29b and inhibition of dnmts resulted in cardiac abnormalities, such as pericardial edema, bradycardia, and abnormal expression of genes related to the heart. Similar changes in the levels of miR-29b and dnmts were also detected in the gonads of F0 males and F1 embryos, confirming their effects. Overall, the results suggest that deltamethrin may have adverse effects on heart development in early-stage zebrafish and on reproduction in adult zebrafish. Furthermore, epigenetic modifications may threaten the cardiac function of offspring.
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Cardiotoxicidad , Embrión no Mamífero , Epigénesis Genética , Insecticidas , MicroARNs , Nitrilos , Piretrinas , Pez Cebra , Animales , Pez Cebra/genética , Piretrinas/toxicidad , Nitrilos/toxicidad , MicroARNs/genética , Epigénesis Genética/efectos de los fármacos , Cardiotoxicidad/genética , Masculino , Insecticidas/toxicidad , Femenino , Embrión no Mamífero/efectos de los fármacos , Corazón/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Reproducción/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacosRESUMEN
Acid red 73 is an azo dye, and its residue can pollute the environment and seriously threaten human health and life. In this study, glutaraldehyde was used as the crosslinking agent, chitosan and polyvinyl alcohol were crosslinked under appropriate conditions to obtain a chitosan hydrogel film, and carbon nanotubes were dispersed in the chitosan hydrogel film. The FTIR, XRD, BET, SEM were applied to chatacterize the structure and the morphology of the absorbent and results showed that when the mass fraction of the carbon nanotubes was 1%, the structure was a three-dimensional network with microporous, and the water absorption reached to the maximum value of 266.07% and the elongation at break reached to a maximum of 98.87%. The ability to remove acid red 73 from aqueous and soil environments was evaluated by UV. In the aqueous samples, 70 mg of the adsorbent reached a saturated adsorption capacity of 101.07 mg/g and a removal rate of 92.23% at pH = 5. The thermodynamics conformed with the Langmuir adsorption isotherm and pseudo second-order adsorption kinetic models. In the soil samples, 100 mg of the adsorbent reached an adsorption capacity of 24.73 mg/g and removal rate of 49.45%. When the pH of the soil is between 4 and 7, the removal rate and adsorption capacity do not change much; hence, the pH should be maintained between 5.2 and 6.8, which is extremely suitable for the growth of general plants. Moreover, the experimental results demonstrated that the adsorbent maintained a good removal rate of acid red 73 over six adsorption cycles.
RESUMEN
BACKGROUND: Mnemonic discrimination is very vulnerable to aging. Previous studies have reported that aerobic exercise and enriched cognitive stimulation (e.g., video games) could improve mnemonic discrimination in older adults. The animal model suggested that combining the 2 training methods could result in a larger improvement. However, there is limited evidence on the potential superior efficacy of combined intervention with human participants. Moreover, the neural basis of this potential superior is poorly understood. METHODS: We conducted a 16-week intervention trial with 98 community-dwelling older adults assigned to one of the four groups (combined training, aerobic cycling alone, video game alone, or passive control). Mnemonic discrimination was measured as the primary behavioral outcome, hippocampal volume, and functional connectivity of the default mode network (DMN) were measured as neural indicators. RESULTS: Participants receiving the combined intervention demonstrated the largest effect size of mnemonic discrimination improvement. Magnetic resonance image results indicated aerobic exercising increased left hippocampal volume, while video-game training counteracted the decline of DMN functional connectivity with aging. The synergy of hippocampal structural and functional plasticity observed in the combined training group explained why the largest intervention benefits were obtained by this group. CONCLUSION: Despite the nonrandomized design (i.e., likely self-selection bias), our results provide new evidence that combined intervention of exercise and cognitive training is more effective than single intervention for older adults. Parallel to animal studies, aerobic exercise and the video game with enriched cognitive stimulation could induce hippocampal plasticity through separate structural and functional pathways. CLINICAL TRIALS REGISTRATION NUMBER: ChiCTR1900022702.
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Memoria , Juegos de Video , Humanos , Anciano , Resultado del Tratamiento , Pruebas Neuropsicológicas , Ejercicio Físico/fisiología , Juegos de Video/psicologíaRESUMEN
Cyhexatin (CYT), an organotin acaricide, is extensively utilized in developing countries to mitigate plant diseases caused by mites and minimize agricultural crop losses. However, the comprehensive mechanisms underlying the developmental stage of non-target organisms remain largely unexplored. In this study, zebrafish embryos were firstly exposed to CYT (0.06, 0.12, and 0.20 ng/mL, referred to as CYTL, CYTM, and CYTH, respectively) from 2 hpf (hours post fertilization) to 30 dpf (days post fertilization). No developmental toxicity was observed in the CYTL and CYTM groups, except for induced deformed phenotypes in the CYTM group at 120 hpf. However, exposure to CYTH resulted in significant reductions in spontaneous movement (24 hpf), heart rate (48 hpf), hatching rate (48 and 72 hpf), body weight (30 dpf), whole body length (30 dpf), and locomotion (30 dpf). Additionally, CYTH exposure induced morphological malformations, including spinal curvature, pericardial edema, and tail curvature in zebrafish larvae. Moreover, CYTH treatment induced apoptosis, increased reactive oxygen species (ROS) production, and resulted in significant reductions in free T3, cholesterol, estradiol, and testosterone levels in zebrafish larvae, while free T4 levels were increased. RNA-Seq analysis indicated that CYTH exposure led to significant alterations in the genome-wide gene expression profiles of zebrafish, particularly in the thyroid hormone and steroid biosynthesis signaling pathways, indicating endocrine disruption. Furthermore, CYTH exposure induced global DNA hypomethylation, reduced S-adenosylmethionine (SAM) levels and the SAM/S-adenosylhomocysteine (SAH) ratio, elevated SAH levels, and suppressed the mRNA expression of DNA methyltransferases (DNMTs) while also downregulating DNMT1 at both the gene and protein levels in zebrafish larvae. Overall, this study partially elucidated the developmental toxicity and endocrine disruption caused by CYT in zebrafish, providing evidence of the environmental hazards associated with this acaricide.