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1.
Front Psychol ; 13: 902429, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35910986

RESUMEN

Although the automatic speech recognition (ASR) technology is increasingly used for commercial purposes, its impact on language learning has not been extensively studied. Underpinned by the sociocultural theory, the present work examined the effects of leveraging ASR technology to support English vocabulary learning in a tertiary flipped setting. A control group and an experimental group of college students participated in a 14-week study. Both groups had their English classes in a flipped fashion, but the experimental group was assigned with ASR-assisted oral tasks for pre-class self-learning. The pre- and post-intervention in-class task performance of both groups was audio-recorded and transcribed for data analysis. The triadic complexity-accuracy-fluency (CAF) framework was adopted to evaluate the participants' vocabulary learning. The between- and within-subjects effects were examined mainly through procedures of MANCOVA and mixed-design repeated measures ANCOVA. Results showed that on all the metrics of lexical complexity and speed fluency, the experimental group outperformed the control group, and had significant growth over time. On the other hand, the control group only improved significantly overtime on the G-index. On lexical accuracy, there was no significant difference between the two groups, and the within-subjects effect was not significant for either group. The findings lent some support to Skehan's Trade-off Hypothesis and discussions were conducted regarding the triarchic CAF framework.

2.
Front Psychol ; 13: 903252, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35874347

RESUMEN

STEM education has been regarded as an important educational initiative for cultivating students' twenty-first century skills. The present work aimed to explore ways to promote students' twenty-first century skills through an integrated STEM-based curriculum. Specifically, we designed and implemented an 8-week crossover program of STEM and community service education. In this program, students learned about STEM domain knowledge and community service issues. They then applied the knowledge to solve authentic problems faced by Hong Kong community-housing residents from disadvantaged groups. A mixed-method approach was employed to evaluate the effectiveness of the program in enhancing students' twenty-first century skills and attitudes, including (i) creative thinking, (ii) collaboration, (iii) perseverance, as well as their (iv) STEM career interests. The research participants were 121 secondary students from a government-subsidized school. The quantitative results showed that the participants' creative thinking, collaboration, and perseverance improved alongside their STEM career interests. These findings were further supported by the data gathered through focus-group interviews. This study provides theoretical and practical insights into the integration of STEM education with community service learning.

3.
Artículo en Inglés | MEDLINE | ID: mdl-35730028

RESUMEN

We used the design-based research approach to test and refine a theoretically grounded goal-access-feedback-challenge-collaboration gamification model. The testbed was a 10-week, university-level e-learning design course offered in two consecutive semesters. In Study 1, we implemented the initial goal-access-feedback-challenge-collaboration model in semester one of the 2020-2021 academic year (N = 26). The aim was to enhance student behavioral engagement in online discussion forums, affective engagement in the class, and learning performance. The results of Study 1 showed that although most participants were engaged in this gamified learning experience during the first two sessions, they gradually lost interest and their participation in online discussions dropped over the next eight weeks. Thus, we introduced a new element, fantasy, into the original model. In Study 2, we tested the effectiveness of the goal-access-feedback-challenge-collaboration-fantasy model on students' learning outcomes in semester two of 2020-2021 (N = 23). The results of Study 2 suggested that, compared to the original model, the goal-access-feedback-challenge-collaboration-fantasy model can better promote students' engagement in online discussion, as measured by increased interaction with peers, learning experience, and learning performance.

4.
Front Nutr ; 9: 851972, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35548580

RESUMEN

Epigallocatechin-3-gallate (EGCG), a frequently studied catechin in green tea, has been shown involved in the anti-proliferation and apoptosis of human nasopharyngeal carcinoma (NPC) cells. However, the underlying molecular mechanism of the apoptotic effects of EGCG has not been fully investigated. Recent literature emphasized the importance of Sirtuin 1 (SIRT1), an NAD+-dependent protein deacetylase, in regulating cellular stress responses, survival, and organismal lifespan. Herein, the study showed that EGCG could significantly inhibit cell proliferation and promote apoptosis of 2 NPC (CNE-2 and 5-8F) cell lines. Moreover, it was also found that SIRT1 is down-regulated by EGCG, and the SIRT1-p53 signaling pathway participates in the effects of EGCG on CNE-2 and 5-8 F cells. Taken together, the findings of this study provided evidence that EGCG could inhibit the growth of NPC cell lines and is linked with the inhibition of the SIRT1-p53 signaling pathway, suggesting the therapeutic potential of EGCG in human NPC.

5.
Plants (Basel) ; 11(9)2022 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-35567274

RESUMEN

Auxin response factors (ARFs) play important roles in plant development and environmental adaption. However, the function of ARFs in cadmium (Cd) accumulation are still unknown. Here, 23 SaARFs were detected in the genome of hyperaccumulating ecotype of Sedum alfredii Hance (HE), and they were not evenly distributed on the chromosomes. Their protein domains remained highly conservative. SaARFs in the phylogenetic tree can be divided into three groups. Genes in the group Ⅰ contained three introns at most. However, over ten introns were found in other two groups. Collinearity relationships were exhibited among ten SaARFs. The reasons for generating SaARFs may be segmental duplication and rearrangements. Collinearity analysis among different species revealed that more collinear genes of SaARFs can be found in the species with close relationships of HE. A total of eight elements in SaARFs promoters were related with abiotic stress. The qRT-PCR results indicated that four SaARFs can respond to Cd stress. Moreover, that there may be functional redundancy among six SaARFs. The adaptive selection and functional divergence analysis indicated that SaARF4 may undergo positive selection pressure and an adaptive-evolution process. Overexpressing SaARF4 effectively declined Cd accumulation. Eleven single nucleotide polymorphism (SNP) sites relevant to Cd accumulation can be detected in SaARF4. Among them, only one SNP site can alter the sequence of the SaARF4 protein, but the SaARF4 mutant of this site did not cause a significant difference in cadmium content, compared with wild-type plants. SaARFs may be involved in Cd-stress responses, and SaARF4 may be applied for decreasing Cd accumulation of plants.

6.
Front Plant Sci ; 13: 884443, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35620688

RESUMEN

Ma bamboo (Dendrocalamus latiflorus Munro) is the most widely cultivated clumping bamboo in Southern China and is valuable for both consumption and wood production. The development of bamboo shoots involving the occurrence of lateral buds is unique, and it affects both shoot yield and the resulting timber. Plant-specific TCP transcription factors are involved in plant growth and development, particularly in lateral bud outgrowth and morphogenesis. However, the comprehensive information of the TCP genes in Ma bamboo remains poorly understood. In this study, 66 TCP transcription factors were identified in Ma bamboo at the genome-wide level. Members of the same subfamily had conservative gene structures and conserved motifs. The collinear analysis demonstrated that segmental duplication occurred widely in the TCP transcription factors of Ma bamboo, which mainly led to the expansion of a gene family. Cis-acting elements related to growth and development and stress response were found in the promoter regions of DlTCPs. Expression patterns revealed that DlTCPs have tissue expression specificity, which is usually highly expressed in shoots and leaves. Subcellular localization and transcriptional self-activation experiments demonstrated that the five candidate TCP proteins were typical self-activating nuclear-localized transcription factors. Additionally, the transcriptome analysis of the bamboo shoot buds at different developmental stages helped to clarify the underlying functions of the TCP members during the growth of bamboo shoots. DlTCP12-C, significantly downregulated as the bamboo shoots developed, was selected to further verify its molecular function in Arabidopsis. The DlTCP12-C overexpressing lines exhibited a marked reduction in the number of rosettes and branches compared with the wild type in Arabidopsis, suggesting that DlTCP12-C conservatively inhibits lateral bud outgrowth and branching in plants. This study provides useful insights into the evolutionary patterns and molecular functions of the TCP transcription factors in Ma bamboo and provides a valuable reference for further research on the regulatory mechanism of bamboo shoot development and lateral bud growth.

7.
J Steroid Biochem Mol Biol ; 221: 106117, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35504423

RESUMEN

Accumulation of androgens mediate alterations in prostate growth and has emerged as an essential factor in benign prostate hyperplasia (BPH). Dihydrotestosterone (DHT), the most potent natural androgen, binds to androgen receptors (AR) and regulates the prostate growth. Many inhibitors of DHT synthesis have been developed to reduce DHT levels and used in the treatment of prostate diseases. However, therapies targeting the elimination of the DHT remain limited. The DHT in prostate is metabolized by UDP-glucuronosyltransferase 2B (UGT2B) and transforms into inactive products. In this study, we analyzed and demonstrated that two enantiomers of naftopidil (NAF), an α1D/1A-adrenoceptor blocker, induced expression and activity of UGT2B in BPH rat prostate models as well as UGT2B15 in human prostate cells, BPH-1. The NAF enantiomers reduced intraprostatic and intracellular DHT levels, thus promoting cell apoptosis. Besides, assays with siRNA UGT2B15 transfection showed that UGT2B15 played an essential role in mediating the effects of the NAF enantiomers. The UGT2B15 mediated the inhibition of AR and PSA expression by NAF enantiomers. The data showed that the mechanism of upregulating UGT2B15 by the NAF enantiomers might differ from that of AR antagonists and 5α-reductase inhibitors. Together, our results demonstrated that NAF enantiomers could be potential and novel UGT2B15 regulators, which accelerated the DHT elimination and promoted apoptosis of BPH-1 cells. This study could help expand the clinical application of NAF and support the development of new therapeutic strategies targeting the elimination of androgens for the treatment of BPH and other androgen-sensitive diseases.


Asunto(s)
Andrógenos , Hiperplasia Prostática , Andrógenos/metabolismo , Andrógenos/farmacología , Animales , Apoptosis , Dihidrotestosterona/metabolismo , Dihidrotestosterona/farmacología , Glucuronosiltransferasa/genética , Glucuronosiltransferasa/metabolismo , Humanos , Hiperplasia , Masculino , Naftalenos , Piperazinas , Próstata/metabolismo , Hiperplasia Prostática/metabolismo , Ratas , Receptores Androgénicos/metabolismo , Uridina Difosfato/metabolismo , Uridina Difosfato/uso terapéutico
8.
Tree Physiol ; 42(9): 1899-1911, 2022 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-35466991

RESUMEN

Bamboo has a unique flowering characteristics of long and unpredictable vegetative period, which differs from annual herbs and perennial woody plants. In order to understand the molecular regulatory mechanism of bamboo flowering, a comprehensive study was conducted in ma bamboo (Dendrocalamus latiflorus Munro), including morphological, physiological and transcriptiome analyses. Differentially expressed genes related to the flowering pathway were identified by comparative transcriptome analysis. DlFT1, a homologous gene of FT/Hd3a, was significantly upregulated in flowering bamboo. Direct differentiation of spikelets from calli occurred and the downstream gene AP1 was upregulated in the transgenic bamboo overexpressing DlFT1. Transgenic rice overexpressing DlFT1 showed a strong early flowering phenotype. DlFT1 and DlTFL1 could interact with DlFD, and DlTFL1 delayed flowering. It is presumed that DlTFL1 plays an antagonistic role with DlFT1 in ma bamboo. In addition, the expression of DlFT1 was regulated by DlCO1, indicating that a CO-FT regulatory module might exist in ma bamboo. These results suggest that DlFT1 is a florigen candidate gene with conservative function in promoting flowering. Interestingly, the results have shown for the first time that DlFT2 can specifically interact with E3 ubiquitin ligase WAV3, while DlFT3 transcripts are mainly nonsense splicing. These findings provide better understanding of the roles of the florigen gene in bamboo and lay a theoretical basis for regulating bamboo flowering in the future.


Asunto(s)
Bambusa , Florigena , Bambusa/genética , Bambusa/metabolismo , Florigena/metabolismo , Flores/genética , Flores/metabolismo , Perfilación de la Expresión Génica , Regulación de la Expresión Génica de las Plantas , Transcriptoma
9.
Biomed Res Int ; 2022: 4293265, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281609

RESUMEN

Objective: Through a network pharmacology method, we screened the main active compounds of Citri Reticulatae Pericarpium (CRP), constructed a drug-ingredient-disease-target network, explored the molecular mechanism of its treatment of myocardial hypertrophy, and validated it by using molecular biology approach. Methods: Traditional Chinese Medicine Systems Pharmacology (TCMSP) and GeneCards were utilised to collect the effective component in CRP and the targets of CRP and myocardial hypertrophy. The STRING database constructed the protein interaction network. The drug-ingredient-disease-target network was outlined by the Cytoscape 3.9.0 software. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were conducted using the Metascape database. Real-time PCR (RT-PCR) and Western blotting were utilised to determine the mRNA and protein level of the critical targets of CRP therapy for myocardial hypertrophy. Results: We found that five practical components of CRP exerted therapeutic effects on myocardial hypertrophy by modulating 41 targets. Further analysis revealed that naringenin was the essential active compound in CRP that regulated myocardial hypertrophy. In addition, we showed that the active compounds of CRP might exert antihypertrophy effects via regulating essential target proteins such as AKT1-, MAPK3-, PPARA-, PPARG-, and ESR1-mediated signaling pathways such as cell proliferation, nuclear receptor activation, and oxidative stress. The molecular biology experiments demonstrated that naringenin inhibited the mRNA level of NPPA and NPPB induced by Ang II and regulated related targets such as AKT1, MAPK3, PPARA, PPARG, and ESR1. Conclusion: CRP could inhibit myocardial hypertrophy through multitarget and multiapproach.


Asunto(s)
Medicamentos Herbarios Chinos , Medicamentos Herbarios Chinos/farmacología , Humanos , Hipertrofia , Medicina Tradicional China/métodos , Simulación del Acoplamiento Molecular , Farmacología en Red , PPAR gamma , ARN Mensajero
10.
Front Plant Sci ; 13: 822022, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35222480

RESUMEN

Moso bamboo (Phyllostachys edulis) is the most important monopodial bamboo species worldwide. Without a genetic transformation system, it is difficult to verify the functions of genes controlling important traits and conduct molecular breeding in moso bamboo. Here, we established a plant regeneration system from immature embryos. Calli were induced on MS medium added 4-6 mg⋅L-1 2,4-dichlorophenoxyacetic acid (2,4-D) with high efficiency (>60%). A plant growth regulator combination of 0.5 mg⋅L-1 1-naphthylacetic acid (NAA), 2.0 mg⋅L-1 6-benzylaminopurine (BAP), and 3.0 mg⋅L-1 zeatin (ZT) was suitable for shoot differentiation, and the shoot induction frequency was increased to 43% after 0.5 mg⋅L-1 abscisic acid (ABA) pretreatment. An effective antibiotic screening concentration was determined by hygromycin sensitivity test. We further optimized the Agrobacterium concentration and added vacuum infiltration for infection, which improves the transient expression efficiency. A genetic transformation system was established for the first time in moso bamboo, with the transformation efficiency of approximately 5%. To optimize genome editing, two endogenous U3 small nuclear RNA (snRNA) promoters were isolated and used to drive small guide RNA (sgRNA) expression. The results showed that the PeU3.1 promoter exhibited higher efficiency, and it was used for subsequent genome editing. Finally, homozygous pds1pds2 mutants were obtained by an efficient CRISPR/Cas9 genome-editing system. These technical systems will be conducive to gene functional validation and accelerate the molecular breeding process of moso bamboo.

11.
Int J Mol Sci ; 21(24)2020 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-33327419

RESUMEN

Expansins, a group of cell wall-loosening proteins, are involved in cell-wall loosening and cell enlargement in a pH-dependent manner. According to previous study, they were involved in plant growth and abiotic stress responses. However, information on the biological function of the expansin gene in moso bamboo is still limited. In this study, we identified a total of 82 expansin genes in moso bamboo, clustered into four subfamilies (α-expansin (EXPA), ß-expansin (EXPB), expansin-like A (EXLA) and expansin-like B (EXPB)). Subsequently, the molecular structure, chromosomal location and phylogenetic relationship of the expansin genes of Phyllostachys edulis (PeEXs) were further characterized. A total of 14 pairs of tandem duplication genes and 31 pairs of segmented duplication genes were also identified, which may promote the expansion of the expansin gene family. Promoter analysis found many cis-acting elements related to growth and development and stress response, especially abscisic acid response element (ABRE). Expression pattern revealed that most PeEXs have tissue expression specificity. Meanwhile, the expression of some selected PeEXs was significantly upregulated mostly under abscisic acid (ABA) and polyethylene glycol (PEG) treatment, which implied that these genes actively respond to expression under abiotic stress. This study provided new insights into the structure, evolution and function prediction of the expansin gene family in moso bamboo.


Asunto(s)
Genoma de Planta/genética , Ácido Abscísico/farmacología , Evolución Molecular , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/genética , Estudio de Asociación del Genoma Completo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poaceae/genética , Polietilenglicoles/farmacología , Regiones Promotoras Genéticas/genética , Sintenía
12.
Arch Biochem Biophys ; 640: 37-46, 2018 02 15.
Artículo en Inglés | MEDLINE | ID: mdl-29331689

RESUMEN

AMP-activated protein kinase (AMPK) is a central regulator of multiple metabolic pathways. It has been shown that activation of AMPK could inhibit fibroblast proliferation and extracellular matrix (ECM) accumulation, thereby suppressing cardiac fibrosis. Baicalin, the major component found in skullcap, possesses multiple protective effects on the cardiovascular system. However, little is known about the effect of baicalin on cardiac fibrosis and the molecular mechanism by which baicalin exerts its anti-fibrotic effects has not been investigated. In this study, we revealed that baicalin could inhibit cell proliferation, collagen synthesis, fibronectin (FN) and Connective tissue growth factor (CTGF) protein expression in cardiac fibroblasts induced by angiotensin Ⅱ (Ang Ⅱ). It also ameliorated cardiac fibrosis in rats submitted to abdominal aortic constriction (AAC). Moreover, baicalin inhibited transforming growth factor-ß (TGF-ß)/Smads signaling pathway stimulated with Ang Ⅱ through activating AMPK. Subsequently, we also demonstrated that baicalin attenuated Ang Ⅱ-induced Smad3 nuclear translocation, and interaction with transcriptional coactivator p300, but promoted the interaction of p300 and AMPK. Taken together, these results provide the first evidence that the effect of baicalin against cardiac fibrosis may be attributed to its regulation on AMPK/TGF-ß/Smads signaling, suggesting the therapeutic potential of baicalin on the prevention of cardiac fibrosis and heart failure.


Asunto(s)
Flavonoides/farmacología , Cardiopatías/prevención & control , Miocardio/patología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/efectos de los fármacos , Proteínas Smad/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Angiotensina II/farmacología , Animales , Células Cultivadas , Colágeno/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Relación Dosis-Respuesta a Droga , Fibronectinas/metabolismo , Fibrosis , Cardiopatías/inducido químicamente , Ratas , Ratas Sprague-Dawley
13.
J Colloid Interface Sci ; 509: 360-368, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-28923733

RESUMEN

Controlled demulsification was used to tailor the release of NaCl as a solute from water-in-oil (W/O) emulsion droplets encased in glycerol monostearate (GMS) crystalline shells. Under quiescent conditions at room temperature, the GMS shells behaved as an effective barrier against salt diffusion. A second surfactant, sorbitan monooleate (SMO), added to the emulsion post-preparation to controllably demulsify, resulted in concentration-dependent removal of the interfacially-bound GMS crystals resulting in aqueous droplet coalescence. As a result, NaCl was released from the now-unstable emulsions. Mechanistically, the SMO and GMS demonstrated competitive adsorption for the oil-water interface, with the SMO significantly reducing the displacement energy of the interfacially-bound GMS. Overall, secondary surfactant addition to Pickering emulsions was shown to have important implications for tailoring interfacial composition, and by extension, modulation of the release of solutes from fat crystal-stabilized W/O Pickering emulsions.

14.
Org Lett ; 20(1): 182-185, 2018 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-29240437

RESUMEN

Rhodium(III)- and iridium(III)-catalyzed C-H activation of oximes and coupling with propargyl alcohols is discussed. Depending on the catalyst, the reaction pathway switched between [3 + 2] and [4 + 2] annulations, thus giving divergent access to indenamines and isoquinolines in a one-pot and atom-economical manner. The hydroxyl group in the tertiary propargyl alcohol substrate was found to be crucial in controlling chemoselectivity. Five-membered rhodacycle and iridacycle intermediates have also been identified for mechanism hypotheses.

15.
Med Oncol ; 34(4): 48, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28215024

RESUMEN

Drug therapy for non-small cell lung cancer consists mainly of platinum-based chemotherapy regimens. However, toxicity, drug resistance, and high risk of death have been seen in the clinic, which means there is a need for optimizing the use of medications. Platinum resistance could be mediated by a series of DNA repair pathways, and therefore, these pathways should be taken into account for optimizing drug using. The goal of pharmacogenomics is to elucidate genetic factors, such as DNA repair genes, which might underlie drug efficacy and effectiveness, and to improve therapeutic effects or guide personalized therapy as well. Here, we reviewed the current knowledge of pharmacogenomic data on DNA repair systems and examined whether they could be further translated into the clinic with evidence-based perspectives.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Reparación del ADN/efectos de los fármacos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Humanos , Compuestos Organoplatinos/administración & dosificación , Farmacogenética , Polimorfismo de Nucleótido Simple
16.
J Pharm Biomed Anal ; 132: 165-172, 2017 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-27744175

RESUMEN

Racemic naftopidil (NAF) is used to treat benign prostatic hyperplasia (BPH) and prostatic cancer (PCa). It exhibits greater efficacy but requires higher dose than other ɑ1-adrenoceptor blockers because of its poor bioavailability. It was previously shown that bioavailability of S(-)-NAF (14.5%) was twice that of R(+)-NAF (6.8%). The present study aimed to elucidate the major factors contributing to the poor and enantioselective bioavailability of NAF. First, absorption of NAF enantiomers was examined using a perfusated intestinal model. NAF enantiomers were found to be equally and highly permeable in all segments of the intestine. Second, the metabolites formed in different parts of the intestine and in bile were investigated. Glucuronidation of NAF enantiomers was found to occur primarily in the liver. Third, a new method consisting of ultra performance liquid chromatography coupled with triple-quadruple mass spectrometry (UPLC-MS/MS) was employed to quantify and calculate the pharmacokinetic parameters of NAF enantiomers and their glucuronides after the enantiomers were intravenously injected into rats. The amounts of R(+)-NAF glucuronide (R(+)-NAF-G) and S(-)-NAF glucuronide (S(-)-NAF-G) were six-fold higher than that of R(+)-NAF, and three-fold higher than that of S(-)-NAF. Glucuronidation of S(-)-NAF was faster than that of R(+)-NAF, but the conjugated amount was half of that of R(+)-NAF. Thus, bioavailability of S(-)-NAF was twice that of R(+)-NAF. In conclusion, extensive phase II metabolism in the liver significantly contributes to the low bioavailability of NAF enantiomers. Glucuronidation is the most important metabolic pathway for NAF enantiomers. Glucuronidation of S(-)-NAF is faster but occurs to a lesser extent than that of R(+)-NAF.


Asunto(s)
Hígado/efectos de los fármacos , Naftalenos/metabolismo , Naftalenos/farmacocinética , Piperazinas/metabolismo , Piperazinas/farmacocinética , Animales , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Femenino , Glucurónidos/metabolismo , Infusiones Intravenosas , Intestinos/efectos de los fármacos , Hígado/metabolismo , Masculino , Espectrometría de Masas , Microsomas Hepáticos/metabolismo , Hiperplasia Prostática/tratamiento farmacológico , Control de Calidad , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Estereoisomerismo , Espectrometría de Masas en Tándem , Temperatura
17.
Front Pharmacol ; 8: 984, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29375383

RESUMEN

Naftopidil (NAF) is widely used for the treatment of benign prostatic hyperplasia and prevention of prostate cancer in elderly men. These patients receive a combination of drugs, which involves high risk for drug-drug interaction. NAF exhibits superior efficacy but must be administered at a much higher dosage than other therapeutic drugs. We previously showed that extensive glucuronidation of NAF enantiomers caused poor bioavailability. However, the metabolic pathway and mechanism of action of NAF enantiomer remain to be elucidated. The present study was performed to identify the human UDP-glucuronosyltransferases (UGTs) responsible for the glucuronidation of NAF enantiomers and to investigate the potential inhibition of UGT activity by NAF. The major metabolic sites examined were liver and kidney, which were compared with intestine. Screening of 12 recombinant UGTs showed that UGT2B7 primarily contributed to the metabolism of both enantiomers. Moreover, enzyme kinetics for R(+)-NAF, UGT2B7 (mean Km, 21 µM; mean Vmax, 1043 pmol/min/mg) showed significantly higher activity than observed for UGT2B4 and UGT1A9. UGT2B4 (mean Km, 55 µM; mean Vmax, 1976 pmol/min/mg) and UGT2B7 (mean Km, 38 µM; mean Vmax, 1331 pmol/min/mg) showed significantly higher catalysis of glucuronidation of S(-)-NAF than UGT1A9. In human liver microsomes, R(+)-NAF and S(-)-NAF also inhibited UGT1A9: mean Ki values for R(+)-NAF and S(-)-NAF were 10.0 µM and 11.5 µM, respectively. These data indicate that UGT2B7 was the principal enzyme mediating glucuronidation of R(+)-NAF and S(-)-NAF. UGT2B4 plays the key role in the stereoselective metabolism of NAF enantiomers. R(+)-NAF and S(-)-NAF may inhibit UGT1A9. Understanding the metabolism of NAF enantiomers, especially their interactions with metabolic enzymes, will help to elucidate potential drug-drug interactions and to optimize the administration of this medicine.

18.
Eur J Pharmacol ; 791: 473-481, 2016 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-27615445

RESUMEN

Naftopidil (NAF) is a α1D/1A adrenoceptor selective drug used for the treatment of both benign prostatic hyperplasia and lower urinary tract symptoms (BPH/LUTS). However, NAF is used as a racemate in clinic. To compare the differences and similarities among two enantiomers and racemate, pharmacological activities were evaluated through rat functional assays in vitro and estrogen/androgen (E/T) induced rat BPH model in vivo. NAF and the two enantiomers showed similar blocking activity on α1 receptor. S-NAF exhibited more α1D/1A adrenoceptor subtype selectivity than R-NAF and the racemate. The selectivity ratios pA2 (α1D)/pA2 (α1B) and pA2 (α1A)/pA2 (α1B) were 40.7- and 16.2-fold, respectively. NAF and its enantiomers effectively prevented the development of rat prostatic hyperplasia via suppressing the increase of the prostatic wet weight, visually. The quantitative analysis of the relative acinus volume, relative stroma volume, relative epithelial volume, epithelial height and expression of proliferating cell nuclear antigen (PCNA) and α-smooth muscle actin (α-SMA) were carried out. S-NAF showed an advantage on the effect of inhibiting prostate wet weight and stroma volume over R-NAF and racemate NAF (P<0.05). Nevertheless, no other significant difference was observed between these two enantiomers. In conclusion, both R-NAF and S-NAF not only relax prostate muscle but also inhibit the prostate growth, thus relieve BPH.


Asunto(s)
Andrógenos/farmacología , Estrógenos/farmacología , Naftalenos/química , Naftalenos/farmacología , Piperazinas/química , Piperazinas/farmacología , Hiperplasia Prostática/inducido químicamente , Hiperplasia Prostática/tratamiento farmacológico , Actinas/metabolismo , Antagonistas de Receptores Adrenérgicos alfa 1/química , Antagonistas de Receptores Adrenérgicos alfa 1/farmacología , Antagonistas de Receptores Adrenérgicos alfa 1/uso terapéutico , Animales , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Masculino , Naftalenos/uso terapéutico , Tamaño de los Órganos/efectos de los fármacos , Piperazinas/uso terapéutico , Antígeno Nuclear de Célula en Proliferación/metabolismo , Próstata/efectos de los fármacos , Próstata/metabolismo , Próstata/patología , Hiperplasia Prostática/metabolismo , Hiperplasia Prostática/patología , Ratas , Ratas Sprague-Dawley , Estereoisomerismo
19.
J Pharm Biomed Anal ; 112: 147-54, 2015 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-25985066

RESUMEN

Naftopidil (NAF) is used as a racemate to treat benign prostatic hyperplasia (BPH) and to prevent prostate cancer. However, racemic NAF has low bioavailability; therefore, it is commonly administered at higher clinical dosages compared to other therapeutic BPH drugs. Differences in interactions between individual enantiomers and biological macromolecules may result in variations in pharmacokinetics and dispositions. This study aimed to investigate the pharmacokinetics, bioavailability and tissue distributions of NAF enantiomers in rats after intragastric administration of the individual enantiomers. A rapid and sensitive liquid chromatography coupled with triple-quadrupole mass spectrometric method (RRLC-MS/MS) was developed and validated for determination of NAF enantiomers in rat plasma, tissues, urine and feces. After intragastric administration, S(-)-NAF in plasma [maximum concentration (C(max)) = 186.4 ng/mL, area under the curve from 0 h to 24h (AUC(0-24 h)) = 877.9 ng h/mL] was significantly higher than that of R(+)-NAF (C(max) = 133.2 ng/mL, AUC(0-24 h) = 602.1 ng h/mL). Moreover, S(-)-NAF bioavailability was twice that of R(+)-NAF. R(+)-NAF distributions in the prostate, liver, and kidney were significantly higher than S(-)-NAF distributions (R/S ratios of 3.16, 1.33, and 2.90, respectively). These data reveal the stereoselective pharmacokinetic profiles of the two enantiomers in rats.


Asunto(s)
Naftalenos/química , Naftalenos/farmacocinética , Piperazinas/química , Piperazinas/farmacocinética , Distribución Tisular/fisiología , Animales , Área Bajo la Curva , Disponibilidad Biológica , Cromatografía Liquida/métodos , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Estereoisomerismo , Espectrometría de Masas en Tándem/métodos
20.
Bioorg Med Chem Lett ; 25(2): 285-7, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25488843

RESUMEN

A series of novel arylpiperazine derivatives was synthesized. The in vitro cytotoxic activities of all synthesized compounds against three human prostate cancer cell lines (PC-3, LNCaP, and DU145) were evaluated by a CCK-8 assay. Compounds 10, 24 and 29 exhibited strong cytotoxic activities against LNCaP cells (IC50 <3µM). In addition, these compounds exhibited weak cytotoxic effects on human epithelial prostate normal cells RWPE-1. The structure-activity relationship (SAR) of these arylpiperazine derivatives was also discussed based on the obtained experimental data.


Asunto(s)
Antineoplásicos/farmacología , Proliferación Celular/efectos de los fármacos , Diseño de Fármacos , Piperazinas/síntesis química , Piperazinas/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Masculino , Modelos Moleculares , Estructura Molecular , Neoplasias de la Próstata/patología , Relación Estructura-Actividad , Células Tumorales Cultivadas
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