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1.
Biol Reprod ; 2023 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-38084072

RESUMO

HAND2 is a critical mediator of progesterone action in endometrial stromal cells. Silencing of Hand2 expression in mouse uterus leads to an unopposed FGFR-mediated action that causes female mice infertility. To investigate the involvement of HAND2-FGFR signaling in pathogenesis of adenomyosis, immunohistochemistry, in-situ hybridization, and quantitative real time PCR were employed to assess gene expression in the normal endometrium, the paired eutopic endometrium and ectopic lesions obtained from women with adenomyosis. DNA methylation in the regions of HAND2 promoter and the first exon was also monitored in these samples. Our results revealed that HAND2 expression were dramatically reduced, but FGF9 expression and FGFR-ERK1/2-mediated MAPK signaling pathway were enhanced in the eutopic endometrium and ectopic lesions of patients with adenomyosis compared to the normal controls. Interestingly, expression of HAND2-AS1, a long noncoding RNA resides adjacent to HAND2 in genome, was also reduced in adenomyosis. DNA methylation analysis revealed that the bidirectional promoter between HAND2 and HAND2-AS1, and the first exon of HAND2 gene was heavily methylated in the eutopic endometrium and the ectopic lesions of adenomyosis. To investigate regulation of gene expression by HAND2-AS1, HAND2-AS1 expression was silenced in human endometrial stromal cells. In contrast to the down regulation of HAND2 in response to HAND2-AS1 silencing, FGF9 expression was augmented significantly. Endometrial stromal cells lacking HAND2-AS1 exhibited enhanced proliferation and migration potentials. Collectively, our studies revealed a new molecular mechanism by which HAND2-AS1 is involved in the pathogenesis of adenomyosis via modulating HAND2-FGFR-mediated signaling.

2.
J Chemother ; : 1-8, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37975589

RESUMO

We conducted a meta-analysis to evaluate the efficacy and safety of veliparib in the treatment of advanced/metastatic breast cancer. Databases were searched for relevant studies till June 2023. Six RCTs involving 1912 patients were included. The pooled analysis provided evidence that veliparib-containing regimens could significantly improve the PFS (HR: 0.71; 95% CI: 0.61-0.83; p < 0.0001), OS (HR: 0.87; 95% CI: 0.76-0.99; p = 0.03), and ORR (RR: 1.52; 95% CI:1.06-2.18; p = 0.02) than those of controls for treating advanced/metastatic breast cancer. Breast cancer patients with BRCA-mutation tended to have a better PFS than the BRCA-wildtype group, and patients with TNBC tended to associated with a longer PFS than the non-TNBC group. Veliparib could significantly increase the risk of anemia, leukopenia, neutropenia, diarrhea, stomatitis, fatigue, and peripheral neuropathy. Anemia and neutropenia should be well concerned. The veliparib-containing regimen was efficacious in treating advanced/metastatic breast cancer with a controllable safety factor.

3.
J Endocr Soc ; 7(6): bvad049, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-37153110

RESUMO

HAND2 is a critical mediator of progesterone receptor signaling in endometrium. Silencing of HAND2 expression is associated with female infertility and endometrial cancers. We recently observed that lncRNA HAND2-AS1 and HAND2 are expressed coordinately in human endometrial stromal cells. To investigate involvement of HAND2-AS1 and HAND2 in pathogenesis of endometriosis, we employed immunohistochemistry, in situ hybridization, and quantitative real-time PCR to assess their expression in normal endometrium and the ectopic lesions obtained from patients with ovarian endometriosis. HAND2 promoter methylation was also monitored in these samples. Our results revealed that HAND2 and HAND2-AS1 expression levels were reduced but promoter methylation was enhanced significantly in ectopic endometrium when compared with the normal controls. Fluorescence in situ hybridization showed that HAND-AS1 is predominantly localized in the nuclei of endometrial stromal cells in contrast to the cytoplasmic distribution in epithelial cell compartment. To further investigate regulation of HAND2 expression by HAND2-AS1, HAND2-AS1 was silenced or overexpressed in human endometrial stromal cells. Our studies showed that expression levels of HAND2 and its direct target IL15 were attenuated markedly in HAND2-AS1 silenced cells but enhanced significantly in the overexpressed human endometrial stromal cells. Silencing of HAND2-AS1 also impaired endometrial stromal cell decidualization as indicated by downregulation of decidual biomarkers IGFBP1 and PRL. In addition, HAND2 promoter methylation was also enhanced upon HAND2-AS1 silencing. RNA immunoprecipitation studies further revealed that HAND2-AS1 is capable of binding to DNA methyltransferase DNMT1, indicating that HAND2-AS1 governs HAND2 expression epigenetically involving DNA methylation.

4.
BMC Genomics ; 24(1): 120, 2023 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-36927548

RESUMO

BACKGROUND: The aminoglycosides are established antibiotics that inhibit bacterial protein synthesis by binding to ribosomal RNA. Additional non-antibiotic aminoglycoside cellular functions have also been identified through aminoglycoside interactions with cellular RNAs. The full extent, however, of genome-wide aminoglycoside RNA interactions in Escherichia coli has not been determined. Here, we report genome-wide identification and verification of the aminoglycoside Kanamycin B binding to Escherichia coli RNAs. Immobilized Kanamycin B beads in pull-down assays were used for transcriptome-profiling analysis (RNA-seq). RESULTS: Over two hundred Kanamycin B binding RNAs were identified. Functional classification analysis of the RNA sequence related genes revealed a wide range of cellular functions. Small RNA fragments (ncRNA, tRNA and rRNA) or small mRNA was used to verify the binding with Kanamycin B in vitro. Kanamycin B and ibsC mRNA was analysed by chemical probing. CONCLUSIONS: The results will provide biochemical evidence and understanding of potential extra-antibiotic cellular functions of aminoglycosides in Escherichia coli.


Assuntos
Escherichia coli , RNA , RNA/química , Escherichia coli/genética , Escherichia coli/metabolismo , Antibacterianos/farmacologia , Antibacterianos/metabolismo , Aminoglicosídeos/química , Aminoglicosídeos/metabolismo , Aminoglicosídeos/farmacologia , RNA Ribossômico/química , RNA Mensageiro/genética
5.
Nucleic Acids Res ; 49(18): 10573-10588, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34551436

RESUMO

The twister ribozyme is widely distributed over numerous organisms and is especially abundant in Schistosoma mansoni, but has no confirmed biological function. Of the 17 non-LTR retrotransposons known in S. mansoni, none have thus far been associated with ribozymes. Here we report the identification of novel twister variant (T-variant) ribozymes and their function in S. mansoni non-LTR retrotransposition. We show that T-variant ribozymes are located at the 5' end of Perere-3 non-LTR retrotransposons in the S. mansoni genome. T-variant ribozymes were demonstrated to be catalytically active in vitro. In reporter constructs, T-variants were shown to cleave in vivo, and cleavage of T-variants was sufficient for the translation of downstream reporter genes. Our analysis shows that the T-variants and Perere-3 are transcribed together. Target site duplications (TSDs); markers of target-primed reverse transcription (TPRT) and footmarks of retrotransposition, are located adjacent to the T-variant cleavage site and suggest that T-variant cleavage has taken place inS. mansoni. Sequence heterogeneity in the TSDs indicates that Perere-3 retrotransposition is not site-specific. The TSD sequences contribute to the 5' end of the terminal ribozyme helix (P1 stem). Based on these results we conclude that T-variants have a functional role in Perere-3 retrotransposition.


Assuntos
RNA Catalítico/química , Retroelementos , Schistosoma mansoni/genética , Animais , Sequência de Bases , Genoma Helmíntico , RNA Catalítico/metabolismo , Schistosoma mansoni/enzimologia
6.
J Clin Pharmacol ; 61(11): 1397-1405, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34241895

RESUMO

We performed a systematic review and meta-analysis to fully investigate the thrombocytopenia of platelet-derived growth factor receptor kinase inhibitors (PDGFR-TKIs) in cancer patients. Databases were searched for randomized, controlled trials (RCTs) treated with PDGFR-TKIs until January 2021. The relevant RCTs in cancer patients treated with PDGFR-TKIs were retrieved, and the systematic evaluation was conducted. Nineteen RCTs and 3962 patients were included. Our study suggests that PDGFR-TKIs significantly increased the risks of all-grade (risk ratio [RR], 5.72; 95%CI, 4.32-7.59; P < .00001; I2 = 32%) and high-grade (RR, 5.65; 95%CI, 3.28-9.75; P < .00001; I2 = 0%) thrombocytopenia in cancer patients. Sunitinib is associated with the highest risk of thrombocytopenia among the included PDGFR-TKIs. The RR of high-grade thrombocytopenia varies significantly according to treatment line and median age. The available data suggested that the use of PDGFR-TKIs was associated with a significantly increased risk of thrombocytopenia.


Assuntos
Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Receptores do Fator de Crescimento Derivado de Plaquetas/antagonistas & inibidores , Trombocitopenia/induzido quimicamente , Fatores Etários , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Esquema de Medicação , Humanos , Neoplasias/patologia , Gravidade do Paciente , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
FEBS J ; 288(5): 1586-1598, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32790122

RESUMO

Interactions between aminoglycoside antibiotics and the twister ribozyme were investigated in this study. An initial screen of 17 RNA-binding antibiotics showed that a number of aminoglycosides inhibit the ribozyme, while a subset of aminoglycosides enhances twister cleavage. Initial kinetic analysis of the twister ribozyme showed a sevenfold inhibition of ribozyme cleavage by paromomycin and a fivefold enhancement of cleavage by sisomicin. Direct binding between the twister ribozyme RNA and paromomycin or sisomicin was measured by microscale thermophoresis. Selective 2'-hydroxyl acylation analysed by primer extension shows that both paromomycin and sisomicin induce distinctive tertiary structure changes to the twister ribozyme. Published crystal structures and mechanistic analysis of the twister ribozyme have deduced a nucleobase-mediated general acid-base catalytic mechanism, in which a conserved guanine plays a key role. Here, we show that paromomycin binding induces a structural transition to the twister ribozyme such that a highly conserved guanine in the active site becomes displaced, leading to inhibition of cleavage. In contrast, sisomicin binding appears to change interactions between P3 and L2, inducing allosteric changes to the active site that enhance twister RNA cleavage. Therefore, we show that small-molecule binding can modulate twister ribozyme activity. These results suggest that aminoglycosides may be used as molecular tools to study this widely distributed ribozyme.


Assuntos
Antibacterianos/farmacologia , Paromomicina/farmacologia , RNA Catalítico/genética , Sisomicina/farmacologia , Animais , Pareamento de Bases , Sequência de Bases , Biocatálise , Domínio Catalítico , Cinética , Modelos Moleculares , Conformação de Ácido Nucleico/efeitos dos fármacos , Oligorribonucleotídeos/genética , Oligorribonucleotídeos/metabolismo , RNA Catalítico/agonistas , RNA Catalítico/antagonistas & inibidores , RNA Catalítico/metabolismo , Vespas/química , Vespas/metabolismo
8.
J Clin Pharm Ther ; 46(2): 241-255, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33135237

RESUMO

WHAT IS KNOWN AND OBJECTIVE: PARP inhibitors are currently one of the most promising PARP targeted drugs for patients with certain types of cancer. Gastrointestinal (GI) events are common adverse events for all PARP inhibitors. We conducted this meta-analysis of randomized controlled trials (RCTs) to fully investigate the incidence and the relative risk of GI events in cancer patients receiving PARP inhibitors. STUDY DESIGN: Randomized controlled trials in cancer patients treated with PARP inhibitors were retrieved, and the systematic evaluation was conducted. Embase and PubMed/Medline were searched for articles published till July 2020. RESULTS: Twenty-nine RCTs and 9529 patients were included. The present meta-analysis suggests that the use of PARP inhibitors significantly increases the risk of developing all-grade nausea (RR, 1.46; 95% CI, 1.29-1.66; p < .00001), vomiting (RR, 1.39; 95% CI, 1.17-1.64; p = .0001), diarrhoea (RR, 1.14; 95% CI, 1.06-1.23; p = .0003) and decreased appetite (RR, 1.24; 95% CI, 1.14-1.36; p < .00001), but not for constipation. And the use of these agents significantly increased the risk of high-grade nausea (RR, 1.99; 95% CI, 1.44-2.74; p < .0001), vomiting (RR, 1.54; 95% CI, 1.11-2.14; p = .01) and decreased appetite (RR, 2.03; 95% CI, 1.22-3.40; p = .007), except for diarrhoea and constipation. Nausea was the most common GI event for these agents. Patients receiving veliparib were associated with a relatively lower risk of all-grade nausea and vomiting. Patients with ovarian cancer tend to have a higher risk of all-grade nausea and vomiting than those with non-ovarian cancer. The risk of all-grade nausea and vomiting tended to be higher when PARP inhibitors treatment was longer. WHAT IS NEW AND CONCLUSION: PARP inhibitors were associated with a significant increased risk of GI events. Clinicians should be aware of these risks and perform regular monitoring.


Assuntos
Gastroenteropatias/induzido quimicamente , Neoplasias/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Feminino , Humanos , Neoplasias Ovarianas/tratamento farmacológico , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Índice de Gravidade de Doença
9.
Virulence ; 11(1): 1432-1442, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33103573

RESUMO

The proliferation of antibiotic resistance has its origins in horizontal gene transfer. The class 1 integrons mediate gene transfer by assimilating antibiotic-resistance genes through site-specific recombination. For the class 1 integrons the first assimilated gene normally encodes an aminoglycoside antibiotic resistance protein which is either an aminoglycoside acetyltransferase (AAC), nucleotidyltransferase - (ANT), or adenyl transferase (AAD). An aminoglycoside-sensing riboswitch RNA in the leader RNA of AAC/AAD that controls the expression of aminoglycoside resistance genes has been previously described. Here we explore the relationship between the recombinant products of integron recombination and a series of candidate riboswitch RNAs in the 5' UTR of aad (aminoglycoside adenyltransferases) genes. The RNA sequences from the 5' UTR of the aad genes from pathogenic strains that are the products of site-specific DNA recombination by class 1 integrons were investigated. Reporter assays, MicroScale Thermophoresis (MST) and covariance analysis revealed that a functional aminoglycoside-sensing riboswitch was selected at the DNA level through integron-mediated site-specific recombination. This study explains the close association between integron recombination and the aminoglycoside-sensing riboswitch RNA.


Assuntos
Acetiltransferases/genética , Aminoglicosídeos/genética , Resistência Microbiana a Medicamentos/genética , Integrons/genética , Riboswitch , Aminoglicosídeos/metabolismo , Sequência de Bases , DNA Bacteriano/genética , Pseudomonas fluorescens/genética , Pseudomonas fluorescens/patogenicidade , Recombinação Genética
10.
RNA ; 26(2): 137-149, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31826924

RESUMO

The 5' untranslated regions (5' UTR) of mRNAs play an important role in the eukaryotic translation initiation process. Additional levels of translational regulation may be mediated through interactions between structured mRNAs that can adopt interchangeable secondary or tertiary structures and the regulatory protein/RNA factors or components of the translational apparatus. Here we report a regulatory function of the 5' UTR mRNA of the spe2 gene (SAM decarboxylase) in polyamine metabolism of the fission yeast Schizosaccharomyces pombe Reporter assays, biochemical experiments, and mutational analysis demonstrate that this 5' UTR mRNA of spe2 can bind to spermidine to regulate translation. A tertiary structure transition in the 5' UTR RNA upon spermidine binding is essential for translation regulation. This study provides biochemical evidence for spermidine binding to regulate translation of the spe2 gene through interactions with the 5' UTR mRNA. The identification of such a regulatory RNA that is directly associated with an essential eukaryotic metabolic process suggests that other ligand-binding RNAs may also contribute to eukaryotic gene regulation.


Assuntos
Regiões 5' não Traduzidas , Adenosilmetionina Descarboxilase/genética , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/metabolismo , Schizosaccharomyces/genética , Espermidina/metabolismo , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Ligantes , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , Schizosaccharomyces/metabolismo
11.
RNA ; 26(2): 150-161, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31767786

RESUMO

The 5' untranslated region (5' UTR) of eukaryotic mRNA plays an important role in translation. Here we report the function of the 5' UTR mRNA of S-adenosylmethionine synthetase (sam1) in translational modulation in the presence of SAM in fission yeast Schizosaccharomyces pombe Reporter assays, binding and chemical probing experiments, and mutational analysis show that the 5' UTR mRNA of sam1 binds to SAM to effect translation. Translational modulation is dependent on a tertiary structure transition in the RNA upon SAM binding. The characterization of such an RNA that is directly associated with an essential metabolic process in eukaryotes provides additional evidence that ligand binding by RNAs plays an important role in eukaryotic gene regulation.


Assuntos
Regiões 5' não Traduzidas , Metionina Adenosiltransferase/genética , Biossíntese de Proteínas/efeitos dos fármacos , RNA Mensageiro/metabolismo , S-Adenosilmetionina/metabolismo , Schizosaccharomyces/genética , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Genes Reporter , Ligantes , RNA Fúngico/genética , RNA Fúngico/metabolismo , RNA Mensageiro/genética , Schizosaccharomyces/metabolismo
12.
Cancer Invest ; 37(6): 253-264, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31303065

RESUMO

We fully investigate the skin toxicities of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in cancer patients. The studies about randomized controlled trials in cancer treatment with EGFR-TKIs were retrieved and the systematic evaluation was conducted. The results suggest that EGFR-TKIs significantly increase the risk of skin toxicities including all-grade rash, pruritus, dry skin, and high-grade rash, pruritus. However, the risk of high-grade dry skin did not increase. Rash was the most common toxicity. Physicians should be aware of skin toxicities and should monitor cancer patients when receiving EGFR-TKIs.


Assuntos
Receptores ErbB/antagonistas & inibidores , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Pele/efeitos dos fármacos , Exantema/induzido quimicamente , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Artigo em Inglês | MEDLINE | ID: mdl-30936094

RESUMO

Class 1 integrons accumulate antibiotic resistance genes by site-specific recombination at aatI-1 sites. Captured genes are transcribed from a promoter located within the integron; for class 1 integrons, the first gene to be transcribed and translated normally encodes an aminoglycoside antibiotic resistance protein (either an acetyltransferase [AAC] or adenyltransferase [AAD]). The leader RNA from the Pseudomonas fluorescens class 1 integron contains an aminoglycoside-sensing riboswitch RNA that controls the expression of the downstream aminoglycoside resistance gene. Here, we explore the relationship between integron-dependent DNA recombination and potential aminoglycoside-sensing riboswitch products of recombination derived from a series of aminoglycoside-resistant clinical strains. Sequence analysis of the clinical strains identified a series of sequence variants that were associated with class I integron-derived aminoglycoside-resistant (both aac and aad) recombinants. For the aac recombinants, representative sequences showed up to 6-fold aminoglycoside-dependent regulation of reporter gene expression. Microscale thermophoresis (MST) confirmed RNA binding. Covariance analysis generated a secondary-structure model for the RNA that is an independent verification of previous models that were derived from mutagenesis and chemical probing data and that was similar to that of the P. fluorescens riboswitch RNA. The aminoglycosides were among the first antibiotics to be used clinically, and the data suggest that in an aminoglycoside-rich environment, functional riboswitch recombinants were selected during integron-mediated recombination to regulate aminoglycoside resistance. The incorporation of a functional aminoglycoside-sensing riboswitch by integron recombination confers a selective advantage for the expression of resistance genes of diverse origins.


Assuntos
Acetiltransferases/genética , Aminoglicosídeos/genética , Expressão Gênica/genética , Integrons/genética , Riboswitch/genética , DNA Bacteriano/genética , Pseudomonas fluorescens/genética , RNA Bacteriano/genética
14.
Phytomedicine ; 53: 243-251, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30668404

RESUMO

BACKGROUND: Astragalosidic acid (LS-102) is a new water-soluble derivative of astragaloside IV - a major effective component isolated from the Chinese herb Astragali Radix. Our previous study showed that LS-102 exhibited potent cardiovascular activity. PURPOSE: The objective of this study was to investigate the pharmacokinetic properties of LS-102 after single-dose, oral administration in beagle dogs by developing and validating an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method. METHOD AND RESULT: The chromatographic separation was performed on a Acquity HSS C18 column (100 mm × 2.1 mm, 1.8 µm) by a gradient elution using a mobile phase consisting of water and acetonitrile at a flow rate of 0.35 ml/min. The analytes were detected with a triple quadrupole tandem mass spectrometry in multiple reaction monitoring mode. Method validation revealed a wide linearity over the range of 2.0-10,000 ng/ml together with satisfactory intra- and inter-day precision, accuracy, and recovery. Stability testing showed that LS-102 spiked into dog plasma was stable for 4 h at room temperature, for up to 2 weeks at -80 °C, and during three freeze-thaw cycles. The method was effectively and successfully applied to the pharmacokinetics of LS-102 after oral administration (5, 10 and 20 mg/kg) to beagle dogs. Peak plasma concentrations are attained within approximately 2 h after oral administration with a half-life ranging from 1.55 h to 4.49 h. The plasma concentration-time curve of LS-102 after oral administration presents the phenomenon of a double-peak absorption phase. The peak concentration and area under the concentration-time curve of LS-102 seemed to increase with the increasing doses proportionally, that suggesting linear pharmacokinetics in dogs. Meanwhile, the doxorubicin (Dox)-injured H9c2 cell model was prepared by incubating the cells in 1 µM Dox for 24 h. MTT assay and LDH release measurement showed that LS-102 protected against Dox-induced cardiomyocyte death. CONCLUSION: The obtained results may help to guide the further pre-clinical research of LS-102 as a potentially novel cardioprotective agent.


Assuntos
Benzoxazóis/sangue , Benzoxazóis/farmacocinética , Cromatografia Líquida/métodos , Saponinas/química , Espectrometria de Massas em Tandem/métodos , Triazinas/sangue , Triazinas/farmacocinética , Triterpenos/química , Administração Oral , Animais , Astragalus propinquus , Benzoxazóis/administração & dosagem , Linhagem Celular , Cromatografia Líquida de Alta Pressão/métodos , Cães , Doxorrubicina/efeitos adversos , Estabilidade de Medicamentos , Medicamentos de Ervas Chinesas/química , Feminino , Meia-Vida , Masculino , Miócitos Cardíacos/efeitos dos fármacos , Ratos , Reprodutibilidade dos Testes , Triazinas/administração & dosagem
15.
Eur J Drug Metab Pharmacokinet ; 44(2): 251-259, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30315409

RESUMO

BACKGROUND AND OBJECTIVES: Astragaloside IV (AGS IV) is the most important bioactive constituent of Radix Astragali. However, its disappointing clinical application is mainly caused by its very low solubility in biologic fluids, resulting in poor bioavailability after oral administration. We recently obtained a novel water-soluble derivative of AGS IV (astragalosidic acid, LS-102) that displayed significant cardioprotective potential against hypoxia-induced injury. The objective of this study was to investigate the intestinal absorption, main pharmacokinetic parameters and acute toxicity of LS-102 in rodents compared with AGS IV. METHODS: An oral dose of LS-102 and AGS IV (20 mg/kg) was administered to Sprague-Dawley (SD) rats, and blood samples were collected at predetermined time points. The plasma concentrations were detected by a validated UHPLC-MS/MS method, and pharmacokinetic parameters were calculated using a compartmental model. In the intestinal permeability study, the transport of LS-102 across Caco-2 cell monolayers was investigated at six concentrations from 6.25 to 250 µM. Moreover, the acute toxicity of LS-102 (40-5000 mg/kg) via a single oral administration was investigated in BALB/c mice. RESULTS: LS-102 was rapidly absorbed, attaining a maximum concentration of 248.7 ± 22.0 ng/ml at 1.0 ± 0.5 h after oral administration. The relative bioavailability of LS-102 was twice that of AGS IV. LS-102 had a Papp (mean) of 15.72-25.50 × 10-6 cm/s, which was almost 500-fold higher than that of AGS IV, showing that LS-102 had better transepithelial permeability and could be better absorbed in the intestinal tract. The acute toxicity study showed no abnormal changes or mortality in mice treated with LS-102 even at the single high dose of 5000 mg/kg body weight. CONCLUSIONS: Oral LS-102 produced a pharmacokinetic profile different from AGS IV with higher bioavailability, while the toxic tolerance was similar to previous estimates. Thus, we speculated that LS-102 might provide better clinical efficacy and be a potential candidate for the new drug development of Radix Astragali.


Assuntos
Benzoxazóis/farmacocinética , Benzoxazóis/toxicidade , Absorção Intestinal/efeitos dos fármacos , Triazinas/farmacocinética , Triazinas/toxicidade , Administração Oral , Animais , Benzoxazóis/análise , Transporte Biológico/efeitos dos fármacos , Transporte Biológico/fisiologia , Células CACO-2 , Feminino , Humanos , Absorção Intestinal/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Saponinas/análise , Saponinas/farmacocinética , Saponinas/toxicidade , Solubilidade , Espectrometria de Massas em Tandem/métodos , Triazinas/análise , Triterpenos/análise , Triterpenos/farmacocinética , Triterpenos/toxicidade , Água/metabolismo
16.
Nanotechnology ; 30(4): 045701, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30460926

RESUMO

A binary nanocomposite composed of two-dimensional (2D) ultrathin ZnIn2S4 nanosheets and one-dimension (1D) TiO2 nanobelts was prepared and applied as a noble-metal-free photocatalyst for hydrogen evolution under solar-light irradiation. The TiO2 nanobelt/ZnIn2S4 nanosheet heterojunction nanocomposites show higher light absorption capacity, larger surface area and higher separation of charge carriers in comparison to pristine TiO2 and ZnIn2S4. As a result, the hydrogen production over the TiO2/ZnIn2S4 nanocomposite with 15 wt% TiO2 can reach up to 348.21 µmol · g-1 · h-1, even without noble metals, which is about 26 and 2.3 times higher than the pristine TiO2 and ZnIn2S4, respectively. Meanwhile, a possible photocatalytic mechanism of TiO2/ZnIn2S4 heterojunction nanocomposites was proposed and corroborated by photoluminescence (PL) spectroscopy and photoelectrochemical (PEC) results. This work paves a way for developing low-cost and high-efficiency noble-metal-free photocatalytic systems for solar-to-hydrogen evolution.

17.
Pharmacol Res ; 130: 110-122, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29408518

RESUMO

Mitochondrial reactive oxygen species (mtROS) directly stimulate the inflammatory cytokines cascades and participate in age-related changes of cardiovascular diseases. Application of small molecule targeting the mtROS is significant towards development of better therapy to combat inflammatory response after myocardial infarction (MI) in the aging heart. Chlorogenic acid (CGA) is a well-known natural compound while the clinical potential is largely stifled by its poor oral absorption. In the present study, we tested the protective effect of a novel chlorogenic acid-phospholipid complex (CGA-PC) against acute post-MI inflammation in aged senescence accelerated mouse model. 10-month-old SAMP8 mice were treated with CGA-PC (equivalent of CGA 10 or 20 mg/kg body weight) or phospholipid randomly by gavage on a daily basis for 2 weeks. mtROS, lipid peroxidation, H2O2 production and oxygen consumption were evaluated in hearts subjected to ischemia reperfusion (I/R) induced by left anterior descending artery ligation. CGA-PC significantly reduced pro-inflammatory cytokines and myocardial necrosis, accompanied by decreased oxidative stress and mitochondrial respiratory deficits. p-JNK, MnSOD and soluble cytochrome c were up-regulated in the necrotic heart tissue, while CGA-PC treatment increased the expression of MKP-1 and inhibited the downstream activation of JNK. Our study indicated that CGA-PC ameliorated post-MI inflammatory response in aging heart and that it might be a promising candidate for the clinical development of CGA.


Assuntos
Ácido Clorogênico/uso terapêutico , Infarto do Miocárdio/tratamento farmacológico , Fosfolipídeos/uso terapêutico , Animais , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Masculino , Camundongos , Mitocôndrias/metabolismo , Infarto do Miocárdio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
18.
Polymers (Basel) ; 10(3)2018 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-30966303

RESUMO

Vinyl Benzoate/Heptadecafluorodecyl acrylate (VBe/HFDA) co-polymers were synthesized and characterized as thickening agents for supercritical carbon dioxide (SC-CO2). The solubility and thickening capability of the co-polymer samples in SC-CO2 were evaluated by measuring cloud point pressure and relative viscosity. The molecular dynamics (MD) simulation for all atoms was employed to simulate the microscopic molecular behavior and the intermolecular interaction of co-polymer⁻CO2 systems. We found that the introduction of VBe group decreased the polymer⁻CO2 interaction and increased the polymer⁻polymer interaction, leading to a reduction in solubility of the co-polymers in SC-CO2. However, the co-polymer could generate more effective inter-chain interaction and generate more viscosity enhancement compared to the Poly(Heptadecafluorodecyl) (PHFDA) homopolymer due to the driving force provided by π-π stacking of the VBe groups. The optimum molar ratio value for VBe in co-polymers for the viscosity enhancement of SC-CO2 was found to be 0.33 in this work. The P(HFDA0.67-co-VBe0.33) was able to enhance the viscosity of SC-CO2 by 438 times at 5 wt. %. Less VBe content would result in a lack of intermolecular interaction, although excessive VBe content would generate more intramolecular π-π stacking and less intermolecular π-π stacking. Both conditions reduce the thickening capability of the P(HFDA-co-VBe) co-polymer. This work presented the relationship between structure and performance of the co-polymers in SC-CO2 by combining experiment and molecular simulations.

19.
J Chemother ; 30(6-8): 323-331, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30663550

RESUMO

We conducted this systematic review to fully investigate the fatigue of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) in cancer patients. The approved and clinical used EGFR-TKIs were selected for the present meta-analysis. The relevant studies of the randomized controlled trials (RCTs) in cancer patients treated with EGFR-TKIs were retrieved and the systematic evaluation was conducted. EMBASE, MEDLINE, and PubMed were searched for articles published till July 2017. Eighteen randomized controlled trials and 14088 patients were included. The current analysis suggested that the use of EGFR-TKIs increased the risk of all-grade fatigue (1.26;95%CI, 1.17-1.36;p < 0.00001) and high-grade (≥grade 3) fatigue (1.47;95%CI, 1.22-1.78;p < 0.0001). On subgroup analysis, the RR of high-grade fatigue varies significantly according to drug type, cancer type, treatment line, and treatment duration. The available data suggested that the use of EGFR-TKIs is associated with a significantly increased risk of fatigue in cancer patients.


Assuntos
Receptores ErbB/metabolismo , Fadiga/induzido quimicamente , Neoplasias/tratamento farmacológico , Inibidores de Proteínas Quinases/efeitos adversos , Inibidores de Proteínas Quinases/uso terapêutico , Antineoplásicos/efeitos adversos , Antineoplásicos/uso terapêutico , Humanos , Neoplasias/metabolismo , Ensaios Clínicos Controlados Aleatórios como Assunto
20.
J Microbiol Methods ; 142: 41-45, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28912109

RESUMO

A biosensor based on localized surface plasmon resonance (LSPR) was developed to detect the antibody of Mycobacterium tuberculosis using the fusion protein CFP10-ESAT6 as an antigen. To explore the diagnostic potential of the biosensor for tuberculosis (TB), the fusion protein CFP10-ESAT6 was immobilized on gold nanorods (Au NRs) by chemical modification, and the functionalized Au NRs were subsequently incubated with serums collected from TB patients, non-tuberculous pulmonary disease patients or healthy individuals. The change in the LSPR properties of Au NRs from the specific interaction between the antigen and antibody was monitored, and detection of the target antibody was completed based on the proposed biosensor. Serum analysis showed that the sensitivity of the biosensor was 79% and the specificity was 92%. Therefore, the LSPR biosensor is a valuable tool for serodiagnosis of TB.


Assuntos
Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Técnicas Biossensoriais/métodos , Proteínas Recombinantes de Fusão/imunologia , Ressonância de Plasmônio de Superfície/métodos , Tuberculose Pulmonar/diagnóstico , Anticorpos Antibacterianos/imunologia , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Ouro/química , Humanos , Nanopartículas Metálicas/química , Mycobacterium tuberculosis/imunologia , Tuberculose Pulmonar/microbiologia
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