RESUMEN
As an environmental factor, temperature impacts the distribution of species and influences interspecific competition. The molecular chaperones encoded by small heat shock proteins (sHsps) are essential for rapid, appropriate responses to environmental stress. This study focuses on Hsp20.8, which encodes a temperature-responsive sHsp in Liriomyza trifolii, an insect pest that infests both agricultural and ornamental crops. Hsp20.8 expression was highest at 39â in L. trifolii pupae and adults, and expression levels were greater in pupae than in adults. Recombinant Hsp20.8 was expressed in Escherichia coli and conferred a higher survival rate than the empty vector to bacterial cells exposed to heat stress. RNA interference experiments were conducted using L. trifolii adults and prepupae and the knockdown of Hsp20.8 expression increased mortality in L. trifolii during heat stress. The results expand our understanding of sHsp function in Liriomyza spp. and the ongoing adaptation of this pest to climate change. In addition, this study is also important for predicting the distribution of invasive species and proposing new prevention and control strategies based on temperature adaptation.
Asunto(s)
Dípteros , Proteínas de Insectos , Animales , Dípteros/genética , Dípteros/fisiología , Proteínas de Insectos/metabolismo , Proteínas de Insectos/genética , Calor , Termotolerancia , Pupa/crecimiento & desarrollo , Pupa/genética , Pupa/metabolismo , Proteínas de Choque Térmico Pequeñas/metabolismo , Proteínas de Choque Térmico Pequeñas/genética , Interferencia de ARNRESUMEN
Liriomyza trifolii, an invasive pest, poses a substantial threat to horticultural and vegetable plants. It spreads rapidly, especially in hot weather, leading to large-scale outbreaks with strong thermotolerance and insecticide resistance. In this study, mortality and LtCYP4g1 expression in L. trifolii were evaluated after thermal and insecticides exposure. Furthermore, functional verification of LtCYP4g1 was conducted through RNA interference and bacterial survival assays in Escherichia coli containing recombinant LtCYP4g1 protein. Results indicated that a short time exposure to high temperature incresed insecticide tolerance of L. trifolii, attributed to decreased mortality and induced LtCYP4g1 expression; LtCYP4g1 was involved in stimulating synthesis of cuticular hydrocarbons (CHCs) and elevating epicuticle lipid content and thickness, and E. coli cells overexpressing LtCYP4g1 exhibited significant tolerance to thermal and insecticide stress. In general, P450-mediated tolerance of L. trifolii was enhanced by high temperature, with LtCYP4g1 playing a role in promoting biosynthesis of CHCs for thickening epidermal lipid barrier and reducing cuticular penetration. This study provides a framework for delving into the function of CYP450s in insecticide detoxification and illustrates the role of global warming in driving the evolution of L. trifolii.
Asunto(s)
Sistema Enzimático del Citocromo P-450 , Insecticidas , Ivermectina , Sistema Enzimático del Citocromo P-450/genética , Sistema Enzimático del Citocromo P-450/metabolismo , Animales , Insecticidas/farmacología , Ivermectina/análogos & derivados , Ivermectina/farmacología , Resistencia a los Insecticidas/genética , Hidrocarburos/metabolismo , Calor , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escarabajos/efectos de los fármacos , Escarabajos/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismoRESUMEN
Liriomyza trifolii is a significant pest of vegetable and ornamental crops across the globe. Microwave radiation has been used for controlling pests in stored products; however, there are few reports on the use of microwaves for eradicating agricultural pests such as L. trifolii, and its effects on pests at the molecular level is unclear. In this study, we show that microwave radiation inhibited the emergence of L. trifolii pupae. Transcriptomic studies of L. trifolii indicated significant enrichment of differentially expressed genes (DEGs) in 'post-translational modification, protein turnover, chaperones', 'sensory perception of pain/transcription repressor complex/zinc ion binding' and 'insulin signaling pathway' when analyzed with the Clusters of Orthologous Groups, Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes databases, respectively. The top DEGs were related to reproduction, immunity and development and were significantly expressed after microwave radiation. Interestingly, there was no significant difference in the expression of genes encoding heat shock proteins or antioxidant enzymes in L. trifolii treated with microwave radiation as compared to the untreated control. The expression of DEGs encoding cuticular protein and protein takeout were silenced by RNA interference, and the results showed that knockdown of these two DEGs reduced the survival of L. trifolii exposed to microwave radiation. The results of this study help elucidate the molecular response of L. trifolii exposed to microwave radiation and provide novel ideas for control.
Asunto(s)
Dípteros , Microondas , Animales , Pupa/genética , Pupa/metabolismo , Proteínas de Choque Térmico/genética , VerdurasRESUMEN
CO poisoning of Pt-group metal catalysts is a long-standing problem, particularly for hydrogen oxidation reaction in proton exchange membrane fuel cells. Here, we report a catalyst of Ru oxide-coated Ru supported on TiO2 (Ru@RuO2/TiO2), which can tolerate 1-3% CO, enhanced by about 2 orders of magnitude over the classic PtRu/C catalyst, for hydrogen electrooxidation in a rotating disk electrode test. This catalyst can work stably in 1% CO/H2 for 50 h. About 20% of active sites can survive even in a pure CO environment. The high CO tolerance is not via a traditional bifunctional mechanism, i.e., oxide promoting CO oxidation, but rather via hydrous metal oxide shell blocking CO adsorption. An ab initio molecular dynamics (AIMD) simulation indicates that water confined in grain boundaries of the Ru oxide layer and Ru surface can suppress the diffusion and adsorption of CO. This oxide blocking layer approach opens a promising avenue for the design of high CO-tolerant electrocatalysts for fuel cells.
RESUMEN
Nanostructured carbon materials with high porosity and desired chemical functionalities are of immense interest because of their wide application potentials in catalysis, environment, and energy storage. Herein, a top-down templating strategy is presented for the facile synthesis of functional porous carbons, based on the direct carbonization of diverse organic precursors with commercially available metal oxide powders. During the carbonization, the metal oxide powders can evolve into nanoparticles that serve as in situ templates to introduce nanopores in carbons. The porosity and heteroatom doping of the prepared carbon materials can be engineered by varying the organic precursors and/or the metal oxides. It is further demonstrated that the top-down templating strategy is applicable to prepare carbon-based single-atom catalysts with iron-nitrogen sites, which exhibit a high power density of 545 mW cm-2 in a H2 -air proton exchange membrane fuel cell.
Asunto(s)
Carbono , Nanoporos , Óxidos , Porosidad , PolvosRESUMEN
OBJECTIVES: A direct evaluation of insulin sensitivity on pituitary response to gonadotropin relasing hormone (GnRH) has not been shown in congenital hypogonadotropic hypogonadism (CHH), despite a growing body of evidence in the association of testosterone concentrations with insulin sensitiviy. The objective of the study was to explore whether increased testosterone concentrations in men with CHH improve insulin sensitivity, or vice versa. DESIGN: A retrospective study at a tertiary centre. PATIENTS: Series of male CHH patients were included from Jannuary 2014 to December 2019. MEASUREMENTS: Insulin sensitivity indices calculated from oral glucose tolerance test and steroid hormone levels were examined in 52 patients with newly diagnosed CHH and 22 healthy controls. Thirty-two of the 52 CHH patients received pulsatile GnRH therapy with follow-up every 3-6 months. RESULTS: Compared to healthy controls, CHH patients had elevated 2 h post-load glucose, HbA1c, fasting insulin, HOMA of insulin resistance (HOMA-IR) and decreased Matsuda index and testosterone (p ≤ .01). The median follow-up for patients (n = 32) who received pulsatile GnRH therapy was 13.5 (11.3-24) months (432 person-months in total). GnRH therapy increased testosterone and Matsuda index (p ≤ .0001), whilst decreased platelet count (p = .04), leptin (p = .04), fasting glucose (p = .01) and HOMA-IR (p < .0001) compared with baseline. The median treatment duration first time to reach the lower limit of normal testosterone concentrations of patients with high and low baseline insulin sensitivity was 15 (95% CI: 8.1-21.9) and 30 months (21.2-38.8), respectively. Correspondingly, after GnRH therapy, luteinizing hormone responsiveness to GnRH provocative test was more vigorous in patients with high insulin sensitivity than those with low insulin sensitivity [17.0 (9.5-25.9) vs. 8.2 (3.3-13.0), p = .01]. CONCLUSION: Pulsatile GnRH therapy elevated testosterone levels in male CHH patients, ameliorated impaired insulin sensitivity and attenuated subclinical inflammatory response, increased insulin sensitivity, in turn, may benefit the efficacy of pulsatile GnRH therapy.
Asunto(s)
Hipogonadismo , Resistencia a la Insulina , Enfermedades de la Hipófisis , Adolescente , Humanos , Masculino , Hormona Folículo Estimulante/uso terapéutico , Glucosa , Hormona Liberadora de Gonadotropina/uso terapéutico , Gonadotropinas/uso terapéutico , Hipogonadismo/tratamiento farmacológico , Insulina/uso terapéutico , Metaboloma , Enfermedades de la Hipófisis/tratamiento farmacológico , Estudios Retrospectivos , Testosterona/uso terapéutico , Adulto JovenRESUMEN
We designed and synthesized 18 substituted indole derivatives containing a triazole scaffold as novel anti-influenza A virus candidates using a bio-isosteric and scaffold-hopping strategy from the lead compound 4-32-2. Most of the target compounds (eg: 6, 7a, 7d, 7f-j, 7l, 7m, 7o, 7q) exhibited potent anti-influenza A virus activity and low cytotoxicity in vitro. In particular, 7a exhibited the most potent anti-IAV activity (IC50: 1.34 ± 0.13 µM) with low cytotoxicity (CC50: > 100 µM), and high selectivity index (SI: > 74.63), which provides a new chemical scaffold for the development of novel anti-IAV drug.
Asunto(s)
Virus de la Influenza A , Triazoles , Antivirales/química , Diseño de Fármacos , Indoles/farmacología , Relación Estructura-Actividad , Triazoles/farmacologíaRESUMEN
The leafminer Liriomyza trifolii is an important insect pest of ornamental and vegetable crops worldwide. Cyromazine is an effective, commonly-used insecticide that functions as a growth regulator, but its effect on L. trifolii has not been previously reported. In this study, transcriptome analysis was undertaken in L. trifolii exposed to cyromazine. Clusters of orthologous groups analysis indicated that a large number of differentially expressed genes responding to cyromazine were categorized as "lipid transport and metabolism", "post-translational modification, protein turnover, chaperones", and "cell wall/membrane/envelope biogenesis". Gene ontology analysis indicated that pathways associated with insect hormones, growth and development, and cuticle synthesis were significantly enriched. In general, the transcriptome results showed that the genes related to insect hormones were significantly expressed after treatment with cyromazine. Furthermore, the combined exposure of L. trifolii to cyromazine and the hormone analogues 20-hydroxyecdysone (20E) or juvenile hormone (JH) indicated that hormone analogues can change the expression pattern of hormone-related genes (20EP and JHEH) and pupal length. The combined application of cyromazine with 20E improved the survival rate of L. trifolii, whereas the combination of JH and cyromazine reduced survival. The results of this study help elucidate the mechanistic basis for cyromazine toxicity and provide a foundation for understanding cyromazine resistance.
Asunto(s)
Dípteros , Hormonas de Insectos , Insecticidas , Animales , Dípteros/genética , Insecticidas/toxicidad , Triazinas/toxicidad , Hormonas Juveniles/farmacologíaRESUMEN
p38 has long been known as a central mediator of protein kinase A (PKA) signaling in brown adipocytes, which positively regulate the transcription of uncoupling protein 1 (UCP-1). However, the physiological role of p38 in adipose tissues, especially the white adipose tissue (WAT), is largely unknown. Here, we show that mice lacking p38α in adipose tissues display a lean phenotype, improved metabolism, and resistance to diet-induced obesity. Surprisingly, ablation of p38α causes minimal effects on brown adipose tissue (BAT) in adult mice, as evident from undetectable changes in UCP-1 expression, mitochondrial function, body temperature (BT), and energy expenditure. In contrast, genetic ablation of p38α in adipose tissues not only markedly facilitates the browning in WAT upon cold stress but also prevents diet-induced obesity. Consistently, pharmaceutical inhibition of p38α remarkably enhances the browning of WAT and has metabolic benefits. Furthermore, our data suggest that p38α deficiency promotes white-to-beige adipocyte reprogramming in a cell-autonomous manner. Mechanistically, inhibition of p38α stimulates the UCP-1 transcription through PKA and its downstream cAMP-response element binding protein (CREB), which form a positive feedback loop that functions to reinforce the white-to-beige phenotypic switch during cold exposure. Together, our study reveals that inhibition of p38α is able to promote WAT browning and confer metabolic benefits. Our study also indicates that p38α in WAT represents an exciting pharmacological target to combat obesity and metabolic diseases.
Asunto(s)
Tejido Adiposo/metabolismo , Imidazoles/uso terapéutico , Proteína Quinasa 14 Activada por Mitógenos/metabolismo , Obesidad/metabolismo , Piridinas/uso terapéutico , Células 3T3-L1 , Adipocitos/efectos de los fármacos , Animales , Reprogramación Celular , Frío , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Dieta Alta en Grasa , Evaluación Preclínica de Medicamentos , Imidazoles/farmacología , Ratones , Ratones Noqueados , Proteína Quinasa 14 Activada por Mitógenos/antagonistas & inhibidores , Proteína Quinasa 14 Activada por Mitógenos/genética , Obesidad/prevención & control , Fenotipo , Piridinas/farmacología , TermogénesisRESUMEN
The leafminer fly, Liriomyza trifolii, is an invasive pest of horticultural and vegetable crops that possesses a robust competitive ability when compared to congeneric species, especially with respect to temperature and insecticide tolerance. Abamectin, which is commonly used to control L. trifolii in the field, was selected as the target insecticide in this study. Our objective was to study the effect of abamectin and high temperature stress on L. trifolii mortality and the expression of genes encoding cytochrome P450 (CYP450s) and heat shock proteins (Hsps) by quantitative real-time reverse transcriptase PCR (qRT-PCR). When L. trifolii was exposed to abamectin followed by exposure to 40 °C (LC50 +HT40), mortality showed a significant increase, whereas exposure to 40 â followed by abamectin (HT40+LC50) reduced mortality relative to abamectin or HT40 alone. Expression of three CYP450s in the CYP4 family was highest in the HT40+LC50 treatment, followed by the LC50+HT40 treatment. The expression levels of CYP18A1 (CYP18 family) were not significantly different among treatments, and CYP301A1 (CYP301 family) was only sensitive to temperature (HT40). The expression of five sHsps showed similar expression patterns and were highly responsive to the LC50+HT40 treatment, followed by the HT40 and HT40+LC50 treatments. Based on CYP450s and Hsps expression levels, our findings that suggest that L. trifolii exhibits adaptive cross-tolerance to high temperature and abamectin. This study provides a framework for selecting the most effective application time for abamectin with respect to controlling L. trifolii, which will ultimately reduce the overuse of pesticides.
RESUMEN
Liriomyza trifolii is an invasive leafminer fly that inflicts damage on many horticultural and vegetable crops. In this study, the effects of elevated temperatures on L. trifolii tolerance to insecticides abamectin (AB), monosultap (MO) and a mixture of abamectin and monosultap (AM) were firstly investigated, then five CYP450 genes (LtCYPs) were cloned, and expression patterns and NADPH cytochrome C reductase (NCR) activity in L. trifolii were compared in response to high temperature stress and insecticide exposure. Results showed elevated temperatures induced expression of LtCYP450s, the expression level of LtCYP4g1, LtCYP4g15 and LtCYP301A1 after exposed to different high temperature were significantly up-regulated compared with the control (25 °C), while there was no significant difference in LtCYP4E21 and LtCYP18A1. Under the joint high temperature and insecticide stress, the expression of LtCYP4g15, LtCYP18A1 and LtCYP301A1 was significantly higher under elevated temperatures than that of only under AB exposure. For MO and AM exposure, only 40 °C could induce the expression of LtCYP4g15, LtCYP18A1 and LtCYP301A1. In general, the LtCYPs expression pattern was correlated with increased NCR activity and decreased mortality in response to insecticide exposure under elevated temperatures. These all demonstrated that insecticide tolerance in L. trifolii could be mediated by high temperature. This study improves our understanding of L. trifolii physiology and offers a theoretical context for improved control that ultimately reduces the abuse of insecticides and decreases exposure to non-target organisms.
Asunto(s)
Dípteros , Insecticidas , Animales , Productos Agrícolas , Sistema Enzimático del Citocromo P-450/genética , Insecticidas/toxicidad , TemperaturaRESUMEN
Heat shock transcription factors (HSFs) play critical roles in several types of environmental stresses. However, the detailed regulatory mechanisms in response to salt stress are still largely unknown. In this study, we examined the salt-induced transcriptional responses of ThHSFA1-ThWRKY4 in Tamarix hispida and their functions and regulatory mechanisms in salt tolerance. ThHSFA1 protein acts as an upstream regulator that can directly activate ThWRKY4 expression by binding to the heat shock element (HSE) of the ThWRKY4 promoter using yeast one-hybrid (Y1H), chromatin immunoprecipitation (ChIP), and dual-luciferase reporter assays. ThHSFA1 and ThWRKY4 expression was significantly induced by salt stress and abscisic acid (ABA) treatment in the roots and leaves of T. hispida. ThHSFA1 is a nuclear-localized protein with transactivation activity at the C-terminus. Compared to nontransgenic plants, transgenic plants overexpressing ThHSFA1 displayed enhanced salt tolerance and exhibited reduced reactive oxygen species (ROS) levels and increased antioxidant enzyme activity levels under salt stress. Therefore, we further concluded that ThHSFA1 mediated the regulation of ThWRKY4 in response to salt stress in T. hispida.
Asunto(s)
Proteínas de Arabidopsis/genética , Factores de Transcripción del Choque Térmico/genética , Estrés Salino/genética , Tamaricaceae/genética , Factores de Transcripción/genética , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacología , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Plantas Modificadas Genéticamente/efectos de los fármacos , Plantas Modificadas Genéticamente/genética , Plantas Modificadas Genéticamente/crecimiento & desarrollo , Especies Reactivas de Oxígeno/metabolismo , Estrés Salino/efectos de los fármacos , Tolerancia a la Sal/efectos de los fármacos , Tolerancia a la Sal/genética , Sales (Química)/toxicidad , Tamaricaceae/efectos de los fármacos , Tamaricaceae/crecimiento & desarrolloRESUMEN
After months of lockdown due to the COVID-19 pandemic, more people are planning regional trips because overseas travel is still not feasible. However, choosing a suitable travel destination during the COVID-19 pandemic is challenging because the factors critical to the selection process are very different from those usually considered. Furthermore, without sufficient literature or data for reference, existing methods based on psychological analyses or mining past experiences may not be applicable. Consequently, a fuzzy multi-criteria decision-making method - the calibrated piecewise-linear fuzzy geometric mean (FGM) approach - is proposed in this study for travel destination recommendation during the COVID-19 pandemic. The contribution of this research is twofold. First, the critical factors that affect the selection of a suitable travel destination during the COVID-19 pandemic are discussed. Second, the accuracy and efficiency using existing fuzzy analytic hierarchy process (FAHP) methods have been enhanced. The calibrated piecewise-linear FGM approach has been successfully applied to recommend suitable travel destinations to fifteen travelers for regional trips in Taiwan during the COVID-19 pandemic.
RESUMEN
Coptidis Rhizoma, as a bulk medicinal material, is in great demand in clinical practice. Its quality is uneven in the market due to the mixture of genuine, counterfeit and adulterants. Therefore, it is particularly important to establish a quality control system for Coptidis Rhizoma. Based on the concept of Chinese medicine quality marker(Q-marker), the potential quality markers of Coptidis Rhizoma were analyzed and predicted from the perspective of chemistry and pharmacology. The sources of the Q-markers of Coptidis Rhizoma were identified by literature retrieval. The potential Q-markers were then screened through the visualization of the "components-targets-pathways" network. High performance liquid chromatography(HPLC) was used to establish a multi-indicator qualitative and quantitative control method featuring fingerprints for 10 batches of Coptidis Rhizoma. A supervised mode of orthogonality partial least squares method-discriminant analysis(OPLS-DA) was used to screen the main marker components that caused differences between groups. The literature review results showed that the alkaloids were the main source of Coptidis Rhizoma Q-markers.The fingerprints of 13 common peaks were successfully established, and berberine, palmatine, berberine and epiberberine were selected as Q-markers of Coptidis Rhizoma, and their contents were determined.Based on the concept of the Q-marker of traditional Chinese medicine, the four components can be selected as the Q-marker of Coptidis Rhizoma after comprehensive consideration. The results of this study are not only conducive to the quality evaluation of Coptidis Rhizoma on the market, but also provide a reference for the overall quality control of Coptidis Rhizoma and lay foundation for the future exploration of the mechanism of Coptidis Rhizoma.
Asunto(s)
Alcaloides , Medicamentos Herbarios Chinos , Cromatografía Líquida de Alta Presión , Análisis Multivariante , RizomaRESUMEN
The rational design of catalytically active sites in porous materials is essential in electrocatalysis. Herein, atomically dispersed Fe-Nx sites supported by hierarchically porous carbon membranes are designed to electrocatalyze the hydrazine oxidation reaction (HzOR), one of the key techniques in electrochemical nitrogen transformation. The high intrinsic catalytic activity of the Fe-Nx single-atom catalyst together with the uniquely mixed micro-/macroporous membrane support positions such an electrode among the best-known heteroatom-based carbon anodes for hydrazine fuel cells. Combined with advanced characterization techniques, electrochemical probe experiments, and density functional theory calculation, the pyrrole-type FeN4 structure is identified as the real catalytic site in HzOR.
RESUMEN
A series of novel HIV-1 protease inhibitors has been designed and synthesized, which contained morpholine derivatives as the P2 ligands and hydrophobic cyclopropyl as the P1' ligand at the meantime in this study, with the aim of improving the interactions between the active sites of HIV-1 protease and the inhibitors. Twenty-eight compounds were synthesized and assessed, among which inhibitors m18 and m1 exhibited excellent inhibitory effect on the activity of HIV-1 protease with IC50 value of 47 nM and 53 nM, respectively. The molecular modeling of m1 revealed possible hydrogen bondings or van der Waals between the inhibitor and the protease, worthy of in-depth study.
Asunto(s)
Inhibidores de la Proteasa del VIH/química , Proteasa del VIH/metabolismo , Morfolinas/química , Dominio Catalítico , Diseño de Fármacos , Pruebas de Enzimas , Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/síntesis química , Inhibidores de la Proteasa del VIH/metabolismo , VIH-1/enzimología , Enlace de Hidrógeno , Simulación del Acoplamiento Molecular , Morfolinas/síntesis química , Morfolinas/metabolismo , Unión Proteica , Electricidad EstáticaRESUMEN
In this work, according to the 'me-too me-better' design strategy, a peculiar side chain different from lefamulin at C14 position of pleuromutilin was introduced. A series of novel thioether pleuromutilin derivatives containing cyclohexane in the C14 chain was synthesized by ten-step synthesis reaction. All derivatives were characterized by Nuclear Magnetic Resonance (NMR) and High Resolution Mass Spectrometer (HRMS). Furthermore, majority of derivatives displayed moderate antibacterial activity in vitro. However, the compound 2C and 2J exhibited comparable or superior antibacterial activity to lefamulin. The summarized structure-activity relationship not only made the variety of pleuromutilin derivatives more diverse, but also provided new ideas for its design and development.
Asunto(s)
Antibacterianos/farmacología , Diterpenos/farmacología , Compuestos Policíclicos/farmacología , Antibacterianos/síntesis química , Diterpenos/síntesis química , Diseño de Fármacos , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Compuestos Policíclicos/síntesis química , Staphylococcus epidermidis/efectos de los fármacos , Relación Estructura-Actividad , PleuromutilinasRESUMEN
Chronic tissue injury with fibrosis results in the disruption of tissue architecture, organ dysfunction, and eventual organ failure. Therefore, the development of effective antifibrotic drugs is urgently required. IMB-S7 is novel biphenyl compound derived from bifendate (biphenyldicarboxylate) that is used for the treatment of chronic hepatitis in China. In the current study we investigated the potential of IMB-S7 as an antihepatic fibrosis agent. In bile duct ligation (BDL) rat model, oral administration of IMB-S7 (400 mg· kg-1· d-1, for 14 days) significantly ameliorated BDL-induced liver necrosis, bile duct proliferation, and collagen accumulation. We then showed that IMB-S7 treatment markedly suppressed the TGF-ß/Smad pathway in human hepatic stellate cell line LX2 and mouse primary HSCs, as well as in liver samples of BDL rats, thus inhibiting the transcription of most fibrogenesis-associated genes, including TGF-ß1, COL1A1, and ACTA2. Furthermore, IMB-S7 treatment significantly suppressed the expression of integrin αv at the mRNA and protein levels in TGF-ß-treated LX2 cells and liver samples of BDL rats. Using integrin αv overexpression and silencing, we demonstrated that integrin αv activity correlated positively with the activation of TGF-ß/Smad pathway. Based on dual luciferase assay and DNA affinity precipitation assay, we revealed that IMB-S7 inactivated integrin αv through competitively inhibiting the binding of Sp1, a transcription factor, to the integrin αv (ITGAV) promoter (-173/-163 bp). These results suggest that IMB-S7 inhibits HSCs activation and liver fibrosis through Sp1-integrin αv signaling, and IMB-S7 may be a promising candidate to combat hepatic fibrosis in the future.
Asunto(s)
Compuestos de Bifenilo/farmacología , Integrina alfaV/genética , Cirrosis Hepática/tratamiento farmacológico , Factor de Transcripción Sp1/antagonistas & inhibidores , Animales , Conductos Biliares/cirugía , Compuestos de Bifenilo/síntesis química , Compuestos de Bifenilo/química , Células Cultivadas , Relación Dosis-Respuesta a Droga , Humanos , Integrina alfaV/metabolismo , Cirrosis Hepática/metabolismo , Cirrosis Hepática/cirugía , Estructura Molecular , Ratas , Factor de Transcripción Sp1/metabolismo , Relación Estructura-ActividadRESUMEN
Introducing purine bases to P2-ligands might enhance the potency of Human Immunodeficiency Virus-1 (HIV-1) protease inhibitory because of the carbonyl and NH groups promoting the formation of extensive H-bonding interactions. In this work, thirty-three compounds are synthesized and evaluated, among which inhibitors 16a, 16f and 16j containing N-2-(6-substituted-9H-purin-9-yl)acetamide as the P2-ligands along with 4-methoxylphenylsulfonamide as the P2'-ligand, display potent inhibitory effect on the activity of HIV-1 protease with IC50 43â¯nM, 42â¯nM and 68â¯nM in vitro, respectively.
Asunto(s)
Inhibidores de la Proteasa del VIH/uso terapéutico , Ligandos , Purinas/metabolismo , Inhibidores de la Proteasa del VIH/farmacología , Humanos , Estructura MolecularRESUMEN
The design, synthesis and SAR study of a new series of HIV-1 protease inhibitors with pentacyclic triterpenoids as P2 ligands and phenylsulfonamide as P2' ligands were discussed. These compounds exhibited micromolar inhibitory potency, among which compound T1c displayed HIV-1 protease inhibition with IC50 values of 0.12⯵M, which was 67 times the inhibitory activity of its raw material Ursolic acid (8.0⯵M).