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1.
Redox Biol ; 72: 103130, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38522110

RESUMO

Redox-responsive hydropersulfide prodrugs are designed to enable a more controllable and efficient hydropersulfide (RSSH) supply and to thoroughly explore their biological and therapeutic applications in oxidative damage. To obtain novel activation patterns triggered by redox signaling, we focused on NAD(P)H: quinone acceptor oxidoreductase 1 (NQO1), a canonical antioxidant enzyme, and designed NQO1-activated RSSH prodrugs. We also performed a head-to-head comparison of two mainstream structural scaffolds with solid quantitative analysis of prodrugs, RSSH, and metabolic by-products by LC-MS/MS, confirming that the perthiocarbamate scaffold was more effective in intracellular prodrug uptake and RSSH production. The prodrug was highly potent in oxidative stress management against cisplatin-induced nephrotoxicity. Strikingly, this prodrug possessed potential feedback activation properties by which the delivered RSSH can further escalate the prodrug activation via NQO1 upregulation. Our strategy pushed RSSH prodrugs one step further in the pursuit of efficient release in biological matrices and improved druggability against oxidative stress.


Assuntos
NAD(P)H Desidrogenase (Quinona) , Oxirredução , Estresse Oxidativo , Pró-Fármacos , Sulfetos , Pró-Fármacos/farmacologia , Pró-Fármacos/química , Estresse Oxidativo/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Oxirredução/efeitos dos fármacos , Sulfetos/química , Sulfetos/farmacologia , Humanos , Animais , Espectrometria de Massas em Tandem , Cisplatino/farmacologia , Antioxidantes/farmacologia , Antioxidantes/química , Camundongos
2.
Cells ; 12(19)2023 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-37830561

RESUMO

Alzheimer's disease (AD), an age-related degenerative disorder, is characterized by ß-amyloid deposition, abnormal phosphorylation of tau proteins, synaptic dysfunction, neuroinflammation, and oxidative stress. Despite extensive research, there are no medications or therapeutic interventions to completely treat and reverse AD. Herein, we explore the potential of hydrocortisone (HC), a natural and endogenous glucocorticoid known to have potent anti-inflammatory properties, in an Aß1-42-induced AD mouse model. Our investigation highlights the beneficial effects of HC administration on cognitive impairment, synaptic function enhancement, and neuronal protection in Aß1-42-induced AD mice. Notably, HC treatment effectively suppresses the hyperactivation of microglia and astrocytes, leading to a reduction in proinflammatory factors and alleviation of neuroinflammation. Furthermore, HC intervention demonstrates the capacity to mitigate the generation of ROS and oxidative stress. These compelling findings underscore the potential therapeutic application of HC in AD and present promising opportunities for its utilization in AD prevention and treatment. The implications drawn from our findings indicate that hydrocortisone holds promise as a viable candidate for adjunctive use with other anti-AD drugs for the clinical management of patients presenting with moderate to severe AD.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Camundongos , Animais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Hidrocortisona/farmacologia , Doenças Neuroinflamatórias , Disfunção Cognitiva/tratamento farmacológico , Estresse Oxidativo
3.
J Pharm Biomed Anal ; 234: 115595, 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37487290

RESUMO

VK2809 is a promising drug candidate in Phase II clinical trials for the treatment of non-alcoholic steatohepatitis (NASH). It is a prodrug with a HepDirect strategy, which can achieve selective hepatic metabolic activation, generating an active metabolite VK2809A as a potent and selective agonist for thyroid hormone receptor beta (TRß), a concomitant reactive metabolite VK2809B, and a glutathione (GSH) conjugate MB06588. Currently, there is no convenient and sensitive bioanalytical method for the simultaneous determination of the above three metabolites. Herein, we established an LC-MS/MS method to separate VK2809 and its metabolites on the XSelect HSS T3 column and quantified them in negative electrospray ionization mode. Subsequently, several factors were investigated such as the use of 60% acetonitrile for homogenization to stabilize the analytes, the addition of 20 mM glutathione for the derivation of VK2809B, and the protein precipitation with methanol containing Sobetirome as the internal standard (IS). The method exhibited good linearity for all compounds (19.4-388.4 nM for VK2809; 27.4-2744.4 nM for VK2809A and 10.6-211.0 nM for MB06588) with great correlation coefficients (r > 0.996). The method validation also demonstrated acceptable precision (RSD < 13.0% for VK2809, RSD < 7.9% for VK2809A, RSD < 14.4% for MB06588) and accuracy (92.7%-103% for VK2809, 91.2%-107.3% for VK2809A, 96%-106.7% for MB06588). The matrix effect, recovery, and stability were also suitable to determine all the analytes. This method is suitable for the bioanalysis of VK2809 and its metabolites and has been successfully applied to the study of intrahepatic exposure in rats. It is expected to be further practiced in drug design, optimization, and metabolism study in the following research.


Assuntos
Organofosfonatos , Espectrometria de Massas em Tandem , Ratos , Animais , Cromatografia Líquida/métodos , Espectrometria de Massas em Tandem/métodos , Fígado , Reprodutibilidade dos Testes
4.
ACS Appl Mater Interfaces ; 15(29): 35082-35091, 2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37458304

RESUMO

This study aimed to develop effective adsorbents for capturing radioactive iodine in nuclear power waste gas. Two zinc metal-organic frameworks (Zn-MOFs) were synthesized and found to have favorable properties such as a large surface area, thermal stability, surface rich in π-electron-containing nitrogen, and redox potential. Adsorption experiments revealed maximum capacities of 1.25 and 1.96 g g-1 for the MOFs at 75 °C, with the pseudo-second-order kinetic model fitting the data well. The Langmuir equation provided a better fit in cyclohexane, with maximum adsorption amounts of 249 and 358 mg g-1 for Zn-MOF-1 and Zn-MOF-2, respectively. The MOFs were also stable during six cycles of adsorption and desorption. Furthermore, electron transfer occurred due to the synergistic adsorption of Zn, N, and O atoms, resulting in the conversion of some iodine to polyiodide. Zn-MOF-2 exhibited better chemisorption than Zn-MOF-1 due to a smaller highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap. Notably, it was discovered that N-containing radicals had stronger interactions with iodine compared to radicals without N. These findings provide valuable insights into MOF synthesis and environmental protection.

5.
Sci Total Environ ; 847: 157452, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-35868390

RESUMO

The traditional biological nitrogen removal technology consists of two steps: nitrification by autotrophs in aerobic circumstances and denitrification by heterotrophs in anaerobic situations; however, this technology requires a huge area and stringent environmental conditions. Researchers reached the conclusion that the denitrification process could also be carried out in aerobic circumstances with the discovery of aerobic denitrification. The aerobic denitrification process is carried out by aerobic denitrifying bacteria (ADB), most of which are heterotrophic bacteria that can metabolize various forms of nitrogen compounds under aerobic conditions and directly convert ammonia nitrogen to N2 for discharge from the system. Despite the fact that there is no universal agreement on the mechanism of aerobic denitrification, this article reviewed four current explanations for the denitrification mechanism of ADB, including the microenvironment theory, theory of enzyme, electron transport bottlenecks theory, and omics study, and summarized the parameters affecting the denitrification efficiency of ADB in terms of carbon source, temperature, dissolved oxygen (DO), and pH. It also discussed the current status of the application of aerobic denitrification in practical processes. Following the review, the difficulties of present aerobic denitrification technology are outlined and future research options are highlighted. This review may help to improve the design of current wastewater treatment facilities by utilizing ADB for effective nitrogen removal and provide the engineers with relevant references.


Assuntos
Desnitrificação , Purificação da Água , Aerobiose , Amônia , Bactérias Aeróbias/metabolismo , Carbono/metabolismo , Processos Heterotróficos , Nitrificação , Nitritos/metabolismo , Nitrogênio/metabolismo , Oxigênio , Águas Residuárias/química
6.
Chemistry ; 28(36): e202200540, 2022 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-35390207

RESUMO

The newly emerging persulfide prodrugs provide additional options for the profound study of persulfide, a fascinating molecule expected to intervene in biological functions and even diseases. Peroxynitrite is often the culprit in pathological processes characterized by oxidative stress, while the persulfide prodrug responsive to it is still pending. To enrich the family of redox-activated prodrugs, we designed prodrugs with a 2-oxo-2-phenylacetamide trigger, which achieved the release of persulfide via 1, 6-N, S-relay. The degradation of prodrugs and the formation of persulfides were confirmed to be peroxynitrite-responsible by the qualitative and quantitative studies based on LC-MS/MS methods and a spectrophotometry-based tag-switch strategy. Furthermore, these prodrugs showed potent peroxynitrite scavenging activity, cellular therapeutic potential against paracetamol poisoning in HepG2 and oxidative stress in H9c2, as well as desirable in vitro metabolic properties.


Assuntos
Pró-Fármacos , Acetaminofen , Cromatografia Líquida , Ácido Peroxinitroso , Pró-Fármacos/farmacologia , Sulfetos , Espectrometria de Massas em Tandem
7.
J Pharm Biomed Anal ; 208: 114437, 2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-34735992

RESUMO

ZL-01 is a novel dual-prodrug which shows promise to be an antiviral candidate for hepatitis C virus. Here we have established a liquid chromatography tandem mass spectrometry (LC-MS/MS) method for simultaneous determination of ZL-01 and its four metabolites (M1, M7, M8, and M9) in rat plasma with special consideration of ex vivo ZL-01, M1, and M7 stability. Several factors affecting the stability were investigated. EDTA and citric acid solution (1 M) were added to plasma to maintain the stability of analytes. The protein-precipitation method was selected with acetonitrile containing sofosbuvir as internal standard (IS). Adequate separation of ZL-01 and its metabolites was achieved on XSelect HSS T3 (3.5 µm, 4.6 × 150 mm) column by a gradient-elution with a mobile phase consisting of 0.1% formic acid and acetonitrile at a flow rate of 0.5 mL/min. The detection was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring (MRM) mode to monitor the precursor-to-product ion transitions of m/z 599.2→418.5 for ZL-01, m/z 529.7→398.2 for M1, m/z 330.5→182.0 for M7, m/z 260.3→112.1 for M8, m/z 261.3→113.2 for M9 and m/z 530.4→243.4 for IS. The calibration curves exhibited good linearity (r>0.997) for all components. The lower limit of quantitation (LLOQ) was in the range of 1-2 ng/mL. The intra-day and inter-day precisions (RSD) at three different levels were both less than 10.2% and the accuracies (RE) ranged from -3.7-7.6%. The matrix effect and extraction recovery of them ranged from 84% to 110.3% and 88.3-106.3%. This LC-MS/MS method for the simultaneous quantitation of ZL-01 and its metabolites was developed successfully and applied in the pharmacokinetic studies of these in rats. Pharmacokinetic results indicated ZL-01 would be metabolized rapidly and M8 might be the main metabolites after oral absorption.


Assuntos
Pró-Fármacos , Espectrometria de Massas em Tandem , Animais , Cromatografia Líquida , Nucleotídeos , Plasma , Ratos , Reprodutibilidade dos Testes
8.
Biomaterials ; 279: 121174, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34715636

RESUMO

Unmet needs for small diameter, non-biologic vascular grafts and the less-than-ideal performance of medium diameter grafts suggest opportunities for major improvements. Biomaterials that are mechanically matched to native blood vessels, reduce the foreign body capsule (FBC) and demonstrate improved integration and healing are expected to improve graft performance. In this study, we developed biostable, crosslinked polyurethane formulations and used them to fabricate scaffolds with precision-engineered 40 µm pores. We matched the scaffold mechanical properties with those of native blood vessels by optimizing the polyurethane compositions. We hypothesized that such scaffolds promote healing and mitigate the FBC. To test our hypothesis, polyurethanes with 40 µm pores, 100 µm pores, and non-porous slabs were implanted subcutaneously in mice for 3 weeks, and then were examined histologically. Our results show that 40 µm porous scaffolds elicit the highest level of angiogenesis, cellularization, and the least severe foreign body capsule (based on a refined assessment method). This study presents the first biomaterial with tuned mechanical properties and a precision engineered porous structure optimized for healing, thus can be ideal for pro-healing vascular grafts and in situ vascular engineering. In addition, these scaffolds may have wide applications in tissue engineering, drug delivery, and implantable device.


Assuntos
Elastômeros , Poliuretanos , Animais , Materiais Biocompatíveis , Prótese Vascular , Camundongos , Porosidade , Engenharia Tecidual , Alicerces Teciduais
9.
J Org Chem ; 86(8): 5518-5529, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33779172

RESUMO

A copper-mediated cyclization and dimerization of indole derived oxime acetate was developed to generate a series of biimidazo[1,2-a]indole scaffolds with two contiguous stereogenic quaternary carbons in one step.


Assuntos
Cobre , Indóis , Acetatos , Catálise , Ciclização , Dimerização , Estrutura Molecular , Oximas
10.
J Org Chem ; 86(1): 91-102, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33280380

RESUMO

A novel metal-free protocol for the effective and efficient construction of pyrrolo[2,1-a]isoquinolines via a diethyl azodicarboxylate (DEAD)-promoted oxidative [3 + 2] cycloaddition/aromatization tandem reaction is described. Instead of the reported two-component oxidation systems, DEAD, as the sole oxidant, could smoothly transfer the tertiary amines to azomethine ylides via oxidation-deprotonation tandem process. The reaction proceeded with a broad substrate scope, giving rise to products in moderate to good isolated yields.

11.
Carbohydr Polym ; 220: 30-42, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31196548

RESUMO

Low molecular weight heparin (LMWH) is a natural sulfated glycosaminoglycan with the affinity to proangiogenic factors, rendering it a promising agent for tumor therapy. Inspired by DOX binding to the helix of DNA, mitochondrial damage KLA peptide derivative (mKLA) and anti-angiogenic LMWH-chrysin conjugate (LC) are constructed to simulate the double strands for doxorubicin (DOX) binding (LKD nanocomplex). Initiated and "locked" by DOX, mKLA and LC temporarily aggregate by π-π stacks, electrostatic and hydrophobic interactions in aqueous condition with self-amplified DOX loading (19.07 ± 1.08 wt%). During endosome-lysosome trafficking, DOX protonated by H+ could "unlock" the LKD nanocomplex to disassemble, which enables mKLA and DOX to damage mitochondria and nucleus DNA respectively, and LMWH could also inhibit angiogenesis. Based on the strong inhibition of tumors at all stages in vivo, we hold that LKD nanocomplex provides a new opportunity based on smart construction of carbohydrate materials for clinically advanced cancer patients.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Doxorrubicina/uso terapêutico , Heparina de Baixo Peso Molecular/química , Nanoconjugados/uso terapêutico , Neoplasias/tratamento farmacológico , Peptídeos/uso terapêutico , Inibidores da Angiogênese/química , Inibidores da Angiogênese/farmacologia , Animais , DNA/química , Doxorrubicina/química , Doxorrubicina/farmacologia , Flavonoides/química , Células Hep G2 , Hepatócitos/efeitos dos fármacos , Humanos , Peptídeos e Proteínas de Sinalização Intercelular , Camundongos Nus , Mitocôndrias/efeitos dos fármacos , Nanoconjugados/química , Peptídeos/química , Peptídeos/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
12.
Biomed Pharmacother ; 111: 638-648, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30611988

RESUMO

Bromocriptine, the most commonly used dopamine (DA) receptor agonists for prolactinoma, can effectively reduce tumor size of prolactinoma, but the mechanism was not fully understood. Apoptosis had been well-recognized to contribute to the tumor mass regression caused by bromocriptine. However, whether other types of non-apoptotic cell death involved in the bromocriptine-induced prolactinoma shrinkage had not been fully clarified. The newly discovered molecular mechanism of necroptosis provides the possibility to examine this programmed necrosis in the pharmacological function of bromocriptine. The aim of present study was to evaluate and investigate the underlying mechanism of necroptosis in involution of prolactinoma induced by bromocriptine. By immunohistochemistry, we found that the numbers of receptor-interacting serine-threonine kinase 3(RIP3) and phosphorylated mixed lineage kinase domain-like protein (pMLKL)-positive cells and their expression intensities were increased in patients with prolactinoma after bromocriptine therapy. For further exploring the mechanism of bromocriptine, prolactinoma cell line (MMQ cells) was adopted to study the mechanism of necroptosis in vitro. Cell viability and ATP level of MMQ cells were decreased, while reactive oxygen species (ROS) level was increased after bromocriptine treatment. The above effects could be partially reversed by Necrostatin-1, an inhibitor of necroptosis. Ultrastructural study further confirmed the necroptosis of MMQ cells, which was characterized by ruptured membrane, dissolved cytoplasm and especially the dramatically swollen mitochondria. Furthermore, we demonstrated that bromocriptine induced RIP3/MLKL-dependent necroptosis of prolactinoma cells and phosphoglycerate mutase family 5(PGAM5)/ Cyclophilin D (CypD) pathway was involved. The results suggested that necroptosis might be a promising target for clinical therapy for prolactinoma.


Assuntos
Bromocriptina/farmacologia , Ciclofilinas/metabolismo , Proteínas Mitocondriais/metabolismo , Fosfoproteínas Fosfatases/metabolismo , Prolactinoma/metabolismo , Proteínas Quinases/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Adolescente , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Bromocriptina/uso terapêutico , Sobrevivência Celular , Agonistas de Dopamina/farmacologia , Agonistas de Dopamina/uso terapêutico , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/tratamento farmacológico , Necrose/metabolismo , Necrose/patologia , Prolactinoma/tratamento farmacológico , Prolactinoma/patologia , Ratos , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Adulto Jovem
13.
J Org Chem ; 83(21): 13121-13131, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30351938

RESUMO

A practical metal-free oxidative Ugi-type three-component assembly has been achieved efficiently, employing a tertiary-amine-derived iminium ion as an imine surrogate, N-hydroxyimide as an acid surrogate, and DEAD as an oxidant. This dual-surrogate Ugi variant proceeded with a broad substrate scope and desired functional group tolerance, leading to a wide range of N-alkyl- N-acyl aminophthalimide and N-alkyl- N-acylaminosuccinimide derivatives in good isolated yields.

14.
Artigo em Inglês | MEDLINE | ID: mdl-29558739

RESUMO

To improve bioavailability and provide resistance to deamination, an array of gemcitabine (dFdC) prodrugs carrying the acyl modifications has been successful in the optimization of pharmacokinetic properties of dFdC, but the reports about 4-N-carbobenzoxy-dFdC (Cbz-dFdC), a dFdC prodrug bearing alkyloxycarbonyl modification, are relatively rare. Notably, in vivo enzymatic hydrolysis was an absolutely essential factor for the activation of these prodrugs, which is correlated with the anti-tumor activity. Therefore, detailed metabolism studies of Cbz-dFdC should be carried out for a more authentic pharmacodynamic evaluation. In order to detect the pharmacokinetic characteristics of Cbz-dFdC, a selective, sensitive and accurate method for the simultaneous determination of Cbz-dFdC, along with dFdC and its major metabolite dFdU in rat plasma was developed and validated using UFLC-MS/MS techniques. Column was at 40 °C for separation using an eluent with acetonitrile and 0.1% formic acid, 1 mM ammonium formate at a flow rate of 0.2 mL/min. Detection was performed using ESI source in positive ion selected reaction monitoring mode by monitoring the following ion transitions m/z 398.1 → 202.2 (Cbz-dFdC), m/z 264.1 → 112.0 (dFdC), m/z 265.3 → 113.2 (dFdU) and m/z 246.1 → 112.0 (IS). Analytes were extracted by simple precipitation with acetonitrile containing internal standards followed by liquid-liquid extraction with ethyl acetate. The calibration curves of Cbz-dFdC, dFdC and dFdU were linear in the concentration range of 2 to 500 ng/mL, 2 to 500 ng/mL and 40 to 10,000 ng/mL, respectively. The assay ranges selected for the three analytes were appropriate and minimized the need for reanalysis. All the validation data, such as intra- and inter-day precision, accuracy, selectivity and stability, were within the required limits. In conclusion, the sensitive analytical assay was selective and accurate for the determination of rat plasma concentrations of Cbz-dFdC, dFdC and dFdU from a single LC-MS/MS analysis and well-suited to support pharmacokinetic studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Desoxicitidina/análogos & derivados , Floxuridina/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Animais , Desoxicitidina/sangue , Desoxicitidina/química , Desoxicitidina/farmacocinética , Estabilidade de Medicamentos , Floxuridina/sangue , Floxuridina/química , Floxuridina/farmacocinética , Modelos Lineares , Masculino , Pró-Fármacos/análise , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Gencitabina
15.
Zhongguo Zhong Yao Za Zhi ; 42(7): 1390-1394, 2017 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-29052404

RESUMO

To discuss the effects of total glucosides from white paeony on preventing and treating radioactive liver damage, and explore its possible mechanisms. Thirty-six patients with primary hepatic carcinoma from 105th Hospital of Chinese PLA were treated with 3-dimensional conformal radiotherapy and randomly divided into simple irradiation group, total glucosides from white paeony group, and control group. The levels of AST, ALT, HA, LN, PCⅢ, CIV and TGF-ß1 in serum of various groups were determined by using ELISA method. As compared with the simple irradiation group and control group, total glucosides from white paeony could obviously decrease the levels of AST, ALT, HA, LN, PCⅢ, CIV and TGF-ß1(P<0.05, P<0.01). The results showed that the total glucosides from white paeony could effectively prevent and treat radioactive liver damage, and its mechanism might be associated with decreasing the levels of TGF-ß1, and inhibiting the synthesis of collagen synthesis.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Glucosídeos/farmacologia , Fígado/efeitos da radiação , Paeonia/química , Lesões por Radiação/tratamento farmacológico , Humanos , Fígado/efeitos dos fármacos , Fator de Crescimento Transformador beta1/sangue , Resultado do Tratamento
16.
J Pharm Biomed Anal ; 146: 147-153, 2017 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-28881311

RESUMO

Tenofovir (TFV), a first-line anti-viral agent, has been prepared as various forms of prodrugs for better bioavailability, lower systemic exposure and higher target cells loading of TFV to enhance efficacy and reduce toxicity. TFV undergoes intracellular phosphorylation to form TFV diphosphate (TFV-DP) in target cell to inhibit viral DNA replication. Hence, TFV-DP is the key active metabolite that exhibits anti-virus activity, its intracellular exposure and half-life determine the final activity. Therefore, simultaneous monitoring prodrug, TFV and TFV-DP in target cells will comprehensively evaluate TFV prodrugs, both considering the stability of ester prodrug, and the intracellular exposure of TFV-DP. Thus we intended to develop a convenient general analytical method, taking tenofovir alafenamide (TAF) as a representative of TFV prodrugs. A sensitive LC-MS/MS method was developed, and TAF, TFV and TFV-DP were separated on a XSelect HSS T3 column (4.6mm×150mm, 3.5µm, Waters) with gradient elution after protein precipitation. The method provided good linearity for all the compounds (2-500nM for TFV and TAF; 20-5000nM for TFV-DP) with the correlation coefficients (r) greater than 0.999. Intra- and inter-day accuracies (in terms of relative error, RE<10.4%) and precisions (in terms of coefficient of variation, CV<14.1%) satisfied the standard of validation. The matrix effect, recovery and stability were also within acceptable criteria. Finally, we investigated the intracellular pharmacokinetics of TAF and its active metabolites in HepG2.2.15 cells with this method.


Assuntos
Adenina/análogos & derivados , Fármacos Anti-HIV/metabolismo , Hepatócitos/metabolismo , Organofosfatos/metabolismo , Pró-Fármacos/química , Tenofovir/metabolismo , Adenina/metabolismo , Adenina/farmacologia , Alanina , Fármacos Anti-HIV/farmacologia , Linhagem Celular Tumoral , Cromatografia Líquida/métodos , Replicação do DNA/efeitos dos fármacos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/metabolismo , HIV-1/efeitos dos fármacos , Meia-Vida , Células Hep G2 , Hepatócitos/virologia , Humanos , Organofosfatos/farmacologia , Pró-Fármacos/farmacologia , Espectrometria de Massas em Tandem/métodos , Tenofovir/farmacologia , Replicação Viral/efeitos dos fármacos
17.
J Med Chem ; 60(14): 6077-6088, 2017 07 27.
Artigo em Inglês | MEDLINE | ID: mdl-28650160

RESUMO

Resistant HCV variants carrying NS5B S282T mutation confer reduced sensitivity to sofosbuvir, the sole marketed NS5B polymerase inhibitor. On the basis of the finding that 2'-α-F-2'-ß-C-methylcytidine 5'-triphosphate (8) was more potent than sofosbuvir's active metabolite on inhibition of both wild-type and S282T mutant polymerase, a dual-prodrug approach has been established. Twenty-nine phosphoramidates with N4-modified cytosine were designed, synthesized, and evaluated for anti-HCV activity. The results showed that compounds 4c-4e and 4m (EC50 = 0.19-0.25 µM) exhibited comparable potency to that of sofosbuvir (EC50 = 0.15 µM) on inhibition of wild-type replicons. Notably, 4c (EC50 = 0.366 µM) was 1.5-fold more potent than sofosbuvir (EC50 = 0.589 µM) on inhibition of S282T mutant replicons. In vitro metabolic studies disclosed the possible metabolic pathways of 4c. The toxicity study results indicated a good safety profile of 4c. Together, 4c-4e and 4m hold promise for drug development for the treatment of HCV infection, especially the resistant variants with NS5B S282T mutation.


Assuntos
Alanina/análogos & derivados , Antivirais/química , Monofosfato de Citidina/análogos & derivados , Hepacivirus/efeitos dos fármacos , Nucleotídeos/síntese química , Pró-Fármacos/síntese química , Alanina/síntese química , Alanina/farmacocinética , Alanina/farmacologia , Animais , Antivirais/síntese química , Antivirais/farmacologia , Linhagem Celular Tumoral , Monofosfato de Citidina/síntese química , Monofosfato de Citidina/farmacocinética , Monofosfato de Citidina/farmacologia , Cães , Feminino , Hepacivirus/genética , Humanos , Fígado/metabolismo , Masculino , Mutação , Nucleotídeos/farmacocinética , Nucleotídeos/farmacologia , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , RNA Polimerase Dependente de RNA/genética , Replicon , Estereoisomerismo , Relação Estrutura-Atividade , Proteínas não Estruturais Virais/genética
18.
Org Lett ; 19(7): 1566-1569, 2017 04 07.
Artigo em Inglês | MEDLINE | ID: mdl-28290693

RESUMO

A novel Ugi-type reaction triggered by 1,5-hydride shift has been established, giving access to N-arylprolinamides and related compounds in high atom economy and good yields. This is an example of a two starting material-three component reaction. The benzyl alcohol substrate 1 acts as a dual synthon, which upon treatment with a Brønsted acid affords iminium ion and water. Nucleophilic attack at the iminium ion by the third component isocyanide, followed by hydrolysis with the endogenic water, gives the Ugi-type reaction products. The reaction proceeds under mild conditions and is tolerable to a broad scope of substrates.

19.
Artigo em Inglês | MEDLINE | ID: mdl-28056427

RESUMO

Crocin and crocetin in rat plasma were simultaneously analysed using ultra-performance liquid chromatography tandem mass spectroscopy (UPLC-MS/MS), and method was fully validated. For the first time, levels of both crocin and crocetin in plasma were profiled after oral administration of crocin, and this UPLC-MS/MS approach was applied to evaluate pharmacokinetics and relative bioavailability of crocin and crocetin in rats. It was shown that crocin transformed into crocetin quickly in the gastrointestinal tract, and crocetin was 56-81 fold higher exposed in rat plasma than crocin after oral administration of crocin. A comparison study revealed that an oral administration of equal molar crocin achieved higher exposure of crocetin in rat plasma than that of crocetin. It was suggested that oral administration of crocin has the advantages over crocetin, and crocetin may be the active component potentially responsible for the pharmacological effect of crocin.


Assuntos
Carotenoides/sangue , Carotenoides/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Carotenoides/administração & dosagem , Cromatografia Líquida/métodos , Feminino , Injeções Intravenosas , Modelos Lineares , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrometria de Massas em Tandem/métodos , Vitamina A/análogos & derivados
20.
Acta Pharmacol Sin ; 38(3): 351-361, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28042874

RESUMO

Berberrubine (BRB) is the primary metabolite of berberine (BBR) that has shown a stronger glucose-lowering effect than BBR in vivo. On the other hand, BRB is quickly and extensively metabolized into berberrubine-9-O-ß-D-glucuronide (BRBG) in rats after oral administration. In this study we compared the pharmacokinetic properties of BRB and BRBG in rats, and explored the mechanisms underlying their glucose-lowering activities. C57BL/6 mice with HFD-induced hyperglycemia were administered BRB (50 mg·kg-1·d-1, ig) for 6 weeks, which caused greater reduction in the plasma glucose levels than those caused by BBR (120 mg·kg-1·d-1) or BRB (25 mg·kg-1·d-1). In addition, BRB dose-dependently decreased the activity of α-glucosidase in gut of the mice. After oral administration of BRB in rats, the exposures of BRBG in plasma at 3 different dosages (10, 40, 80 mg/kg) and in urine at different time intervals (0-4, 4-10, 10-24 h) were dramatically greater than those of BRB. In order to determine the effectiveness of BRBG in reducing glucose levels, we prepared BRBG from the urine pool of rats, and identified and confirmed it through LC-MS-IT-TOF and NMR spectra. In human normal liver cell line L-O2 in vitro, treatment with BRB or BRBG (5, 20, 50 µmol/L) increased glucose consumption, enhanced glycogenesis, stimulated the uptake of the glucose analog 2-NBDG, and modulated the mRNA levels of glucose-6-phosphatase and hexokinase. However, both BBR and BRB improved 2-NBDG uptake in insulin-resistant L-O2 cells, while BRBG has no effect. In conclusion, BRB exerts a stronger glucose-lowering effect than BBR in HFD-induced hyperglycemia mice. Although BRB significantly stimulated the insulin sensitivity and glycolysis in vitro, BRBG may have a greater contribution to the glucose-lowering effect because it has much greater system exposure than BRB after oral administration of BRB. The results suggest that BRBG is a potential agent for reducing glucose levels.


Assuntos
Berberina/análogos & derivados , Glucuronídeos/uso terapêutico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/uso terapêutico , Animais , Berberina/administração & dosagem , Berberina/sangue , Berberina/metabolismo , Berberina/farmacocinética , Berberina/uso terapêutico , Berberina/urina , Glucuronídeos/sangue , Glucuronídeos/urina , Humanos , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacocinética , Masculino , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley
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