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1.
Adv Exp Med Biol ; 1141: 101-202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571165

RESUMO

Solute carrier (SLC) family transporters utilize an electrochemical potential difference or an ion gradient generated by primary active transporters for transporting their substrates across biological membranes. These transporters are categorized as facilitated transporters or secondary active transporters. More than 300 SLC transporters have been identified. SLC transporters related to drug transport mainly include SLC21 gene subfamily (organic anion-transporting polypeptides, OATPs), SLC22A gene subfamily (organic anion transporters, OATs; organic cation transporters, OCTs; or organic cation/carnitine transporters, OCTNs), SLC15A gene subfamily (peptide transporters, PEPTs), and SLC47A gene subfamily (multidrug and toxin extrusion, MATEs). In general, OCTs transport organic cations, OATPs transport large and fairly hydrophobic organic anions, OATs transport the smaller and more hydrophilic organic anions, and PEPTs are responsible for the uptake of di-/tripeptides and peptide-like drugs. MATEs are responsible for efflux of organic cations. These transporters also transport some endogenous substances, indicating that the dysfunction of SLCs not only disrupts homeostasis but also largely impacts on the disposition of their substrate drugs. This chapter will discuss these SLC family transporters, with an emphasis on tissue distribution, substrate specificity, transporter physiology, and clinical significance.


Assuntos
Proteínas Carreadoras de Solutos , Animais , Cátions/metabolismo , Humanos , Peptídeos/metabolismo , Preparações Farmacêuticas/metabolismo , Proteínas Carreadoras de Solutos/metabolismo , Especificidade por Substrato , Distribuição Tecidual/fisiologia
2.
Adv Exp Med Biol ; 1141: 505-548, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571173

RESUMO

The placenta is the only organ linking two different individuals, mother and fetus, termed as blood-placental barrier. The functions of the blood-placental barrier are to regulate material transfer between the maternal and fetal circulation. The main functional units are the chorionic villi within which fetal blood is separated by only three or four cell layers (placental membrane) from maternal blood in the surrounding intervillous space. A series of drug transporters such as P-glycoprotein (P-GP), breast cancer resistance protein (BCRP), multidrug resistance-associated proteins (MRP1, MRP2, MRP3, MRP4, and MRP5), organic anion-transporting polypeptides (OATP4A1, OATP1A2, OATP1B3, and OATP3A1), organic anion transporter 4 (OAT4), organic cation transporter 3 (OCT3), organic cation/carnitine transporters (OCTN1 and OCTN2), multidrug and toxin extrusion 1 (MATE1), and equilibrative nucleoside transporters (ENT1 and ENT2) have been demonstrated on the apical membrane of syncytiotrophoblast, some of which also expressed on the basolateral membrane of syncytiotrophoblast or fetal capillary endothelium. These transporters are involved in transport of most drugs in the placenta, in turn, affecting drug distribution in fetus. Moreover, expressions of these transporters in the placenta often vary along with the gestational ages and are also affected by pathophysiological factor. This chapter will mainly illustrate function and expression of these transporters in placentas, their contribution to drug distribution in fetus, and their clinical significance.


Assuntos
Regulação da Expressão Gênica , Proteínas de Membrana Transportadoras , Placenta , Feminino , Humanos , Proteínas de Membrana Transportadoras/genética , Proteínas de Membrana Transportadoras/metabolismo , Placenta/metabolismo , Gravidez , Distribuição Tecidual , Trofoblastos/metabolismo
3.
Adv Exp Med Biol ; 1141: 549-580, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31571174

RESUMO

ATP-binding cassette (ABC) transporters are involved in active pumping of many diverse substrates through the cellular membrane. The transport mediated by these proteins modulates the pharmacokinetics of many drugs and xenobiotics. These transporters are involved in the pathogenesis of several human diseases. The overexpression of certain transporters by cancer cells has been identified as a key factor in the development of resistance to chemotherapeutic agents. In this chapter, the localization of ABC transporters in the human body, their physiological roles, and their roles in the development of multidrug resistance (MDR) are reviewed. Specifically, P-glycoprotein (P-GP), multidrug resistance-associated proteins (MRPs), and breast cancer resistance protein (BCRP/ABCG2) are described in more detail. The potential of ABC transporters as therapeutic targets to overcome MDR and strategies for this purpose are discussed as well as various explanations for the lack of efficacy of ABC drug transporter inhibitors to increase the efficiency of chemotherapy.


Assuntos
Transportadores de Cassetes de Ligação de ATP , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Transportadores de Cassetes de Ligação de ATP/metabolismo , Resistência a Múltiplos Medicamentos/fisiologia , Resistencia a Medicamentos Antineoplásicos/fisiologia , Humanos , Neoplasias/fisiopatologia , Distribuição Tecidual
4.
Prague Med Rep ; 120(2-3): 52-63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31586504

RESUMO

Tyrosine kinase inhibitors have recently become an essential tool in management of chronic myeloid leukaemia (CML). Dasatinib, a representative of those drugs, acts by inhibiting key proteins included in CML development, predominantly Bcr-Abl and Src. Its advantage is that it shows activity in many cases where other agents bring no improvement due to resistance. Pharmacokinetics of dasatinib has specific characteristics that may play an important role in achieving sufficient exposure in patients. Therefore, the key pharmacokinetic properties are summarized in this report. For example, dasatinib absorption is significantly influenced by gastric pH and its modulation can be a source of serious interactions, as well as simultaneous administration of drugs affecting cytochrome P450.


Assuntos
Dasatinibe/farmacocinética , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Sistema Enzimático do Citocromo P-450 , Dasatinibe/uso terapêutico , Resistencia a Medicamentos Antineoplásicos , Ácido Gástrico , Humanos , Concentração de Íons de Hidrogênio , Leucemia Mielogênica Crônica BCR-ABL Positiva/metabolismo , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico
5.
Chem Biol Interact ; 313: 108840, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31585114

RESUMO

BACKGROUND AND OBJECTIVES: Clonidine has been clinically used to treat Tourette's syndrome for decades. There was research finding that clonidine possessed the best risk-benefit ratio, especially for patients associated with attention deficit hyperactivity disorder. CYP2D6 is a significant member of Cytochrome P450 enzymes. The genetic polymorphisms of CYP2D6 greatly affect the clinical effects of drugs even lead to side effects and medical malpractice. Our goal is to research the effect of CYP2D6 genetic polymorphism on the metabolism of clonidine and evaluate the functions of 22 CYP2D6 allelic variants in vitro, which were discovered in Chinese Han population recently. METHODS: This study was carried out through a mature incubation system. The wild-type CYP2D6*1 and 24 variants (CYP2D6*2, CYP2D6*10 and 22 novel CYP2D6 variants) were expressed in insect cells, and the catalytic activity of all the variants were assessed by substrate clonidine. Metabolite 4-OH clonidine was accurately detected via ultra-performance liquid-chromatography tandem mass spectrometry to evaluate the effect of CYP2D6 genetic polymorphism on the clonidine. RESULT: Among the 22 novel CYP2D6 variants, the intrinsic clearance (Vmax/Km) of 21 variants were significantly decreased (from 1.53% to 83.25%) compared to the wild-type. In particular, the following seven variants (CYP2D6* 2, CYP2D6* 10, CYP2D6* 93, CYP2D6* 95, E215K, V327 M and R497C) attract more attention, of which the intrinsic clearance decreased more than 70% compared to the wild-type. Because the variants with significantly reduced intrinsic clearance are more likely to cause adverse reactions than the variants with increased or little changed intrinsic clearance. In addition, the related pharmacokinetic parameters of CYP2D6*92 and CYP2D6*96 could not be acquired for the defect of CYP2D6 nucleotide. CONCLUSION: We comprehensively evaluated the effect of 22 novel CYP2D6 variants on the metabolism of clonidine for the first time and hoped corresponding data provide a reference for metabolism of clonidine for further studies in vivo, and extend our understanding of the clinical drug toxicity or ineffectiveness by CYP2D6 genetic polymorphism.


Assuntos
Clonidina/farmacocinética , Citocromo P-450 CYP2D6/genética , Grupo com Ancestrais do Continente Asiático/genética , Clonidina/metabolismo , Citocromo P-450 CYP2D6/metabolismo , Humanos , Polimorfismo Genético
6.
Medicine (Baltimore) ; 98(40): e17421, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31577757

RESUMO

Regional citrate anticoagulation (RCA) was recommended as the first treatment option for adults by the Kidney Disease Improving Global Outcomes Kidney Foundation in 2012, for the characteristic of sufficient anticoagulation in vitro, but almost no anticoagulation in vivo. Traditionally, the substitute for RCA is calcium-free. This study investigated a simplified protocol of RCA for continuous hemofiltration (CHF) in children using a commercially available substitute containing calcium.An analytical, observational, retrospective study assessed 59 pediatric patients with 106 sessions and 3580 hours of CHF. Values before and after treatment were compared, including Na, ionic calcium (iCa) and HCO3 concentrations, pH, and the ratio of total calcium to iCa (T/iCa). In addition, in vivo and in vitro iCa, treatment time, sessions with continuous transmembrane pressure >200 mm Hg, and sessions with clotting and bleeding were recorded.The average treatment time was 33.8 ±â€Š10.1 hours. In vitro, 88.5% of iCa achieved the target (0.25-0.35 mmol/L), and in vivo, 95.4% of iCa achieved the target (1.0-1.35 mmol/L). There were 8 sessions with a transmembrane pressure >200 mm Hg and 3 sessions with filters clotted. After treatment, there were 2, 1, and 2 sessions with T/iCa > 2.5 (implying citrate accumulation), iCa < 0.9 mmol/L, and iCa > 1.35 mmol/L. No sodium disorders were recorded. There were fewer cases of acidemia and more cases of alkalemia after treatment compared to before.RCA-CHF with a substitute containing calcium and close monitoring could be a safe and effective treatment for children. In addition, the calcium test site in vitro and the adjustment of citrate should be given strict attention.


Assuntos
Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/terapia , Anticoagulantes/farmacocinética , Cálcio/farmacocinética , Ácido Cítrico/farmacocinética , Hemofiltração , Lesão Renal Aguda/etiologia , Anticoagulantes/administração & dosagem , Cálcio/administração & dosagem , Criança , Pré-Escolar , Ácido Cítrico/administração & dosagem , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
7.
J Appl Oral Sci ; 27: e20180663, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31596368

RESUMO

OBJECTIVE: To investigate the use of polymethyl methacrylate (PMMA) electrospun fiber mats containing different amounts of polyethylene oxide (PEO) as a doxycycline delivery system and to test antibacterial activity against an oral pathogen. METHODOLOGY: PMMA powders or PEO (mol wt 200 Kd) (10,20,30% w/w/) were dissolved in N, N-dimethylformamide (DMF) to obtain a final polymer concentration of 15% in DMF (w/v). 2% Doxycycline monohydrate was added to the solutions and submitted to vortex mixing. The solution was transferred to a plastic syringe and fit into a nanofiber electrospinning unit. The parameters applied were: voltage at 17.2 kV; distance of 20 cm between the needle tip and the collector plate; target speed at 2 m/min; and transverse speed at 1cm/min. Syringe pump speed was 0.15 mm/min. The drug release analysis was performed by removing aliquots of the drug-containing solution (in PBS) at specific periods. Doxycycline release was quantified using RP-HPLC. Fiber mats from all groups had their antibacterial action tested against S. mutans based on inhibition halos formed around the specimens. The experiments were performed in triplicate. Gravimetric analysis at specific periods was performed to determine any polymer loss. Morphological characterization of the electrospun fibers was completed under an optical microscope followed by SEM analysis. RESULTS: The addition of PEO to the PMMA fibers did not affect the appearance and diameter of fibers. However, increasing the %PEO caused higher doxycycline release in the first 24 h. Fibers containing 30% PEO showed statistically significant higher release when compared with the other groups. Doxycycline released from the fibers containing 20% or 30% of PEO showed effective against S. mutans. CONCLUSION: The incorporation of PEO at 20% and 30% into PMMA fiber mat resulted in effective drug release systems, with detected antibacterial activity against S. mutans.


Assuntos
Antibacterianos/farmacocinética , Doxiciclina/farmacocinética , Nanofibras/química , Polietilenoglicóis/farmacocinética , Polimetil Metacrilato/farmacocinética , Análise de Variância , Antibacterianos/química , Cromatografia Líquida de Alta Pressão/métodos , Doxiciclina/química , Imersão , Microscopia Eletrônica de Varredura , Peso Molecular , Polietilenoglicóis/química , Polimetil Metacrilato/química , Reprodutibilidade dos Testes , Streptococcus mutans/efeitos dos fármacos , Fatores de Tempo , Água/química
8.
Acta Cir Bras ; 34(8): e201900806, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31618406

RESUMO

PURPOSE: To assess Cyclosporine A (CsA) therapy at an intraperitoneal dose of 15 mg.kg -1 in a rodent model of non-septic renal ischemia. METHODS: Twenty male Wistar rats were randomized to receive CsA therapy or none therapy before undergoing 30 minutes of renal ischemia followed by reperfusion. Additionally, 10 rats were randomized to undergo the same surgical procedure of the aforementioned animals with neither ischemia nor CsA therapy. Twelve hours after kidney ischemia, the left kidneys were evaluated for histological injury according to Park's criteria. Serum creatinine (Cr), urea nitrogen (Ur) and sodium levels were obtained at different times of the experimental protocol. RESULTS: Rodents in the CsA group showed negative results (p<0.05) in serum variables (Cr: 0.41±0.05mg/dL vs . 4.17±1.25mg/dL; Ur: 40.90±3.98mg/dL vs . 187.70±22.93mg/dL) even the non CsA or control group (Cr: 0.35±0.07mg/dL vs . 3.80±1.20mg/dL; Ur: 40.10±4.70mg/dL vs . 184.50±49.80mg/dL). The negative results were also verified in histological evaluation, CsA group had 50% in the very severe grade of lesion, 10% in the severe and 40% in the moderate to severe whereas the control group had 90% in the very severe grade. CONCLUSION: CsA was incapable of preventing the deleterious effects of ischemia-reperfusion injury in rat kidneys.


Assuntos
Ciclosporina/farmacologia , Imunossupressores/farmacocinética , Rim/irrigação sanguínea , Traumatismo por Reperfusão/tratamento farmacológico , Animais , Creatinina/sangue , Modelos Animais de Doenças , Isquemia/prevenção & controle , Rim/efeitos dos fármacos , Masculino , Ratos , Ratos Wistar , Traumatismo por Reperfusão/patologia , Sódio/sangue , Ureia/sangue
9.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3170-3177, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602869

RESUMO

The intestinal absorption characteristics of ten iridoid glycosides and phenolic acids in the Pterocephali Herba were evaluated via rat intestinal valgus model. The intestinal sac fluids at different time after administration of high,medium and low concentrations of Pterocephali Herba extract were collected and ten chemical components in fluid samples were detected by UPLC-PDA. Accumulative absorbed doses( Q) and absorption rate constants( Ka) of ten chemical constituents were calculated,while proportions between Pterocephali Herba extract and intestinal absorption liquid were compared. The results showed that the intestinal absorption of 10 chemical components was linear absorption( R2>0. 9) at different concentrations,which accorded with the zero-order absorption rate. The absorption rate constant was related to the concentration of the drug and the intestinal site,which indicated that intestinal adsorption mechanism of the components were passive diffusion and active transport. Proportions of chemical constituents in intestinal sac fluid were different from those in Pterocephali Herba extract. Therefore,those ten chemical components in Pterocephali Herba extract can be absorbed in whole intestine. Everted intestinal sac model can be used to evaluate intestinal absorption characteristics of ingredients in Pterocephali Herba extract effectively.


Assuntos
Caprifoliaceae/química , Medicamentos de Ervas Chinesas/farmacocinética , Absorção Intestinal , Extratos Vegetais/farmacocinética , Animais , Intestinos , Ratos , Ratos Sprague-Dawley
10.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3562-3568, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602923

RESUMO

The mass spectrometry-based metabolomics method was used to systematically investigate the formation of celastrol metabolites,and the effect of celastrol on endogenous metabolites. The mice plasma,urine and feces samples were collected after oral administration of celastrol. Ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry( UPLC-QTOF-MS) was applied to analyze the exogenous metabolites of celastrol and its altered endogenous metabolites. Mass defect filtering was adopted to screen for the exogenous metabolites of celastrol. Multivariate statistical analysis was used to identify the endogenous metabolites affected by celastrol. Celastrol and its eight metabolites were detected in urine and feces of mice,and 5 metabolites of them were reported for the first time. The hydroxylated metabolites were observed in the metabolism of both human liver microsomes and mouse liver microsomes. Further recombinant enzyme experiments revealed CYP3 A4 was the major metabolic enzyme involved in the formation of hydroxylated metabolites. Urinary metabolomics revealed that celastrol can affect the excretion of intestinal bacteria-related endogenous metabolites,including hippuric acid,phenylacetylglycine,5-hydroxyindoleacetic acid,urocanic acid,cinnamoylglycine,phenylproplonylglycine and xanthurenic acid. These results are helpful to elucidate the metabolism and disposition of celastrol in vivo,and its mechanism of action.


Assuntos
Metabolômica , Triterpenos/farmacocinética , Animais , Cromatografia Líquida de Alta Pressão , Humanos , Espectrometria de Massas , Camundongos , Microssomos Hepáticos/metabolismo , Triterpenos/metabolismo
11.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3569-3575, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602924

RESUMO

To further investigate the metabolism of Tripterygium wilfordii and Paeonia lactiflora micro-emulsion gel in vivo,an LCMS/MS method was established for the determination of triptolide and paeoniflorin in T. wilfordii and P. lactiflora micro-emulsion gel.The extracorporeal recovery rate of blood probe was measured by concentration difference methods( incremental method and decremental method). Meanwhile,the skin and blood micro-dialysis methods of tripterine and paeoniflorin were established,and the pharmacokinetics of T. wilfordii microemulsion gel in skin and blood was studied by micro-dialysis combined with LC-MS/MS quantitative analysis. The results showed that the established method for the determination of triptolide and paeoniflorin in T. wilfordii microemulsion gel was well linear within the required range,and the specificity,recovery rate and degree of precision of the chromatography all conformed to the research requirements of micro-dialysis samples. The stability of freeze-thawing and the residual effect all conformed to the criteria of biological sample methodology. The probe recovery rates measured by incremental method and decremental method were almost consistent with the extracorporeal recovery rate test. The recovery rates of paeoniflorin in skin and blood micro-dialysis were( 30. 60±1. 09) % and( 28. 01± 1. 75) %,respectively. And the recovery rates of skin and blood micro-dialysis were( 26. 79 ± 2. 78) % and( 25. 39±1. 86) %,respectively. The intraday recovery rate of probes was stable within 11 h. The results of pharmacokinetic study showed that the Cmaxvalues of triptolide in skin and blood were( 148. 03±41. 51) and( 76. 77±15. 27) µg·L-1,respectively. And the Tmaxvalues were( 2. 33±0. 29) and( 3. 00± 0) h,respectively. The AUC0-11 hvalues were( 2 814. 05± 1 070. 37) and( 1 580. 63±208. 27) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 20± 0. 33) and( 4. 54± 0. 34) h,respectively. The T1/2 values were( 4. 61±4. 11) and( 1. 07± 0. 13) h,respectively. The Cmaxvalues of paeoniflorin in skin and blood were( 991. 88 ± 152. 22) and( 407. 02±120. 06) µg·L-1,respectively. The Tmaxvalues were( 2. 00±0) h and( 2. 83±0. 29) h,respectively. The AUC0-11 hvalues were( 18 430. 27±3 289. 35) and( 6 338. 59 ± 1 659. 32) µg·h·L-1,respectively. The MRT0-11 hvalues were( 4. 29 ± 0. 16) and( 4. 00±0. 05) h,respectively. The T1/2 values were( 2. 16±0. 43) and( 1. 78±0. 48) h,respectively. The results suggested that micro-emulsion gel played a role in forming skin reservoir through percutaneous penetration. It not only could improve drug transdermal efficiency,but also control the sustained release of drug and form a long-term effect.


Assuntos
Sangue/metabolismo , Medicamentos de Ervas Chinesas/farmacocinética , Paeonia/química , Pele/metabolismo , Tripterygium/química , Cromatografia Líquida , Emulsões , Géis , Humanos , Espectrometria de Massas em Tandem
12.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3576-3581, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602925

RESUMO

To detect the concentration of triptolide in skin and joint after percutaneous administration,an HPLC-MS/MS method and skin and joint micro-dialysis( MD) method of triptolide were established in this study. The separation was achieved on triple quadrupole( AB QTRAP4500) and phenomenex-C18( 4. 6 mm×150 mm,5 µm,luna) column with acetonitrile-water with 0. 1% formic acid( 65 ∶35) as the mobile phase at a flow rate of 0. 7 m L·min-1. An electrospray ionization( ESI) source was applied and operated in the positive multiple reaction monitoring( MRM) mode. The fragment ion for triptolide was m/z 361. 1→145. 0. The effects of different perfusion [Ringer's,PBS( p H 7. 4),30% ethanol saline]drug concentrations and flow rates on the recovery rate,as well as the relationship between the recovery rate and the loss rate were determined by incremental( dialysis) and reduction( retrodialysis) methods.The reduction method was applied in the in vivo study to investigate and determine the stability of the probe recovery rate in 10 h. The results of HPLC-MS/MS detection method conformed to the requirements of biological samples. The perfusion fluid was 30% ethanol saline. The recovery rate of skin and joint probes in vitro of triptolide increased within the flow rate of 0. 5-2. 5 µL·min-1. In order to increase the timeliness of data and the accuracy,the flow rate was determined to be 1 µL·min-1,and the sample interval was determined to be 0. 5 h. The recovery rate of triptolide in skin and joint probes in vitro and the loss rate were stable and equal despite of change of triptolide concentration within 10-200 µg·L-1. This indicated that the effect of drug concentration on the MD probe recovery rate was small,and the recovery rate could be replaced by the loss rate. The loss rate in vivo using MD method was measured at 10 h,indicating that the transfer rate of triptolide was stable within 10 h. The established method of triptolide in MD and HPLC-MS/MS can be applied to investigate the kinetic in skin and joint after percutaneous administration of triptolide.


Assuntos
Diterpenos/farmacocinética , Articulações/metabolismo , Fenantrenos/farmacocinética , Pele/metabolismo , Cromatografia Líquida de Alta Pressão , Compostos de Epóxi/farmacocinética , Humanos , Reprodutibilidade dos Testes , Espectrometria de Massas em Tandem
13.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3582-3587, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602926

RESUMO

Terpenoids are main bioactive components in Tripterygium wilfordii,but the contents of some terpenoids are relatively low. In order to provide scientific evidence for the regulation of terpenoids in T. wilfordii,this research explored the effect of GR24 on accumulations of four diterpenoids( triptolide,tripterifordin,triptophenolide,and triptinin B) in T. wilfordii suspension cells by biological technology and UPLC-QQQ-MS/MS. The results indicated that 100 µmol·L-1 GR24 inhibited the accumulations of triptolide,tripterifordin,triptophenolide,and triptinin B to different degrees. Compared with the control group,the contents of 4 diterpenoids( in the induced group) were down to 96.59%,63.80%,61.02% and 33.59% in 240 h,respectively. Among them,the accumulation of triptinin B iswas significantly inhibited. In addition,the key time point of inhibitory effect was 120 h after induction with GR24 in some diterpenoids. This is the first systematic study focusing on the effect of GR24 on the accumulations of diterpenoids in T. wilfordii suspension cells. The dynamic accumulation ruleregularity of four diterpenoids after induced by GR24 was summarized,which laid a foundation for further study on the chemical response mechanism of terpenoids to GR24.


Assuntos
Diterpenos/farmacocinética , Lactonas/farmacologia , Tripterygium/química , Células Cultivadas , Humanos , Espectrometria de Massas em Tandem , Terpenos
14.
Zhongguo Zhong Yao Za Zhi ; 44(16): 3594-3600, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602928

RESUMO

Cytochrome P450 family is a kind of biocatalyst widely existing in nature. It has many functions such as catalyzing the biosynthesis of plant secondary metabolites and regulating phytoremediation. Based on the analysis of proteome data of Tripterygium wilfordii,the CYP450 gene of T. wilfordii was preliminarily analyzed and predicted by various bioinformatics methods. The results showed that after the expression of T. wilfordii suspension cells was induced by methyl jasmonate,the proteomic data of T. wilfordii were obtained and analyzed,and 10 CYP450 proteins of T. wilfordii were finally screened out. By analyzing the phylogenetic tree constructed with CYP450 gene of Arabidopsis family,the 10 CYP450 proteins were clustered into 6 different CYP450 families. The physical and chemical properties of CYP450 proteins in different families were different. The secondary structure of CYP450 proteins was mainly composed of irregular curls. Eight subcellular localization results of CYP450 proteins were chloroplasts and the rest were plastids. Subsequently,the conserved domains( heme active sites) shared by CYP450 genes were found by analyzing the results of multiple sequence alignment. Finally,by analyzing the transcriptome data of T. wilfordii,the expression distribution of T. wilfordii in different tissues was preliminarily confirmed,which verified its correlation with the biosynthesis of active components of T. wilfordii,and provided important genetic resources for the analysis of biosynthesis pathway of active components of T. wilfordii.


Assuntos
Sistema Enzimático do Citocromo P-450/química , Proteínas de Plantas/química , Tripterygium/enzimologia , Biologia Computacional , Filogenia , Proteômica , Distribuição Tecidual
15.
Lancet ; 394(10200): 793-804, 2019 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-31478503

RESUMO

Antibody-drug conjugates (ADCs) are immunoconjugates comprised of a monoclonal antibody tethered to a cytotoxic drug (known as the payload) via a chemical linker. The ADC is designed to selectively deliver the ultratoxic payload directly to the target cancer cells. To date, five ADCs have received market approval and over 100 are being investigated in various stages of clinical development. In this Therapeutics paper, we review recent clinical experience with the approved ADCs and other promising late-stage candidates on the horizon, following an overview of the biology and chemistry of ADCs and how the individual components of an ADC (antibody [or target], linker and conjugation chemistry, and cytotoxic payload) influence its activity. We briefly discuss opportunities for enhancing ADC efficacy, drug resistance, and future perspectives for this novel antibody-based molecular platform, which has great potential to make a paradigm shift in cancer chemotherapy.


Assuntos
Anticorpos Monoclonais , Antineoplásicos Imunológicos , Imunoconjugados , Neoplasias/tratamento farmacológico , Anticorpos Monoclonais/administração & dosagem , Anticorpos Monoclonais/efeitos adversos , Anticorpos Monoclonais/farmacocinética , Anticorpos Monoclonais/farmacologia , Antineoplásicos Imunológicos/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Antineoplásicos Imunológicos/farmacocinética , Antineoplásicos Imunológicos/farmacologia , Ensaios Clínicos como Assunto , Humanos , Imunoconjugados/administração & dosagem , Imunoconjugados/efeitos adversos , Imunoconjugados/farmacocinética , Imunoconjugados/farmacologia
16.
Medicina (B Aires) ; 79(4): 241-250, 2019.
Artigo em Espanhol | MEDLINE | ID: mdl-31487242

RESUMO

Type 2 diabetes is a chronic, progressive disease with increasing prevalence and still late diagnostic. This leads to an increase in the incidence of chronic complications, with signifi cantly increasing health costs. There is also a delay in the onset of insulin therapy in patients with type 2 diabetes for causes related to both patients and physicians. Despite advances in treatment, a low proportion of patients achieve adequate glycemic control. The high hypoglycemia prevalence, consequence of insulin, has led to the development of a new generation long-acting basal insulins to achieve a more stable and prolonged action profile, reducing the variability and risk of hypoglycemia. The EDITION program evaluated the efficacy and safety of glargine U300 compared to glargine U100 in patients with type 1 and 2 diabetes at different stages of the disease. Gla-300 is a new formulation of insulin glargine which has a more stable and prolonged pharmacokinetic and pharmacodynamic profile. Gla-300 demonstrated efficacy and tolerability comparable to glargine U100, with a significant decrease in the risk of hypoglycemia, at night and in 24 hours, providing greater flexibility in the injection schedule, with a window of 6 hours. No increase in weight was observed compared to glargine U100. Bright study (2018) compared glargine U300 vs. degludec U100, demonstrating greater benefit in relation to the risk of hypoglycemia with Gla-300 during titration period. Gla-300 is a last-generation basal insulin, available to improve metabolic control, with a lower risk of hypoglycemia.


Assuntos
Diabetes Mellitus Tipo 1/tratamento farmacológico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Hipoglicemiantes/administração & dosagem , Insulina Glargina/administração & dosagem , Insulina Glargina/farmacocinética , Medicina Baseada em Evidências , Humanos , Hipoglicemiantes/efeitos adversos , Hipoglicemiantes/farmacocinética , Insulina Glargina/efeitos adversos
17.
Adv Exp Med Biol ; 1148: 115-129, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31482497

RESUMO

Therapeutic proteins are a rapidly growing class of drugs in clinical settings. The pharmacokinetics (PK) of therapeutic proteins relies on their absorption, distribution, metabolism, and excretion (ADME) properties. Moreover, the ADME properties of therapeutic proteins are impacted by their physicochemical characteristics. Comprehensive evaluation of these characteristics and their impact on ADME properties are critical to successful drug development. This chapter summarizes all relevant physicochemical characteristics and their effect on ADME properties of therapeutic proteins.


Assuntos
Proteínas/farmacologia , Proteínas/farmacocinética , Fenômenos Químicos , Proteínas/química , Relação Estrutura-Atividade
18.
Chem Pharm Bull (Tokyo) ; 67(9): 897-903, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474726

RESUMO

The word "theranostics," a portmanteau word made by combining "therapeutics" and "diagnostics," refers to a personalized medicine concept. Recently, the word, "radiotheranostics," has also been used in nuclear medicine as a term that refer to the use of radioisotopes for combined imaging and therapy. For radiotheranostics, a diagnostic probe and a corresponding therapeutic probe can be prepared by introducing diagnostic and therapeutic radioisotopes into the same precursor. These diagnostic and therapeutic probes can be designed to show equivalent pharmacokinetics, which is important for radiotheranostics. As imaging can predict the absorbed radiation dose and thus the therapeutic and side effects, radiotheranostics can help achieve the goal of personalized medicine. In this review, I discuss the use of radiolabeled probes targeting bone metastases, sigma-1 receptor, and αVß3 integrin for radiotheranostics.


Assuntos
Neoplasias Ósseas/diagnóstico , Compostos Radiofarmacêuticos/química , Animais , Neoplasias Ósseas/diagnóstico por imagem , Neoplasias Ósseas/radioterapia , Meios de Contraste/química , Meios de Contraste/metabolismo , Humanos , Oligopeptídeos/química , Oligopeptídeos/metabolismo , Oligopeptídeos/uso terapêutico , Compostos Radiofarmacêuticos/farmacocinética , Compostos Radiofarmacêuticos/uso terapêutico , Receptores sigma/química , Receptores sigma/metabolismo , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único , Distribuição Tecidual
19.
Chem Pharm Bull (Tokyo) ; 67(9): 977-984, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474737

RESUMO

Endomorphin-1 (Tyr-Pro-Trp-Phe-NH2, EM-1), an endogenous µ-opioid receptor ligand with strong antinociceptive activity, is not in clinical use because of its limited metabolic stability and membrane permeability. In this study, we develop a short-peptide self-delivery system for brain targets with the capability to deliver EM-1 without vehicle. Two amphiphilic EM-1 derivatives, C18-SS-EM1 and C18-CONH-EM1, were synthesized by attaching a stearyl moiety to EM-1 via a disulfide and amide bond, respectively. The amphiphilicity of EM-1 derivatives enabled self-assembling into nanoparticles for brain delivery. The study assessed morphology, circular dichroism, and metabolic stability of the formulations, as well as their pharmacodynamics and in vivo distribution, directly monitored by near-IR fluorescence imaging in mouse brains. In aqueous solution, the C18-SS-EM1 derivative self-assembled into spherical nanostructures with a diameter of 10-20 nm. Near-IR fluorescence analysis visualized the accumulation of the peptides in the brain. Importantly, the analgesic effect of C18-SS-EM1 nanoparticles was significantly stronger as compared to that of unmodified EM-1 or C18-CONH-EM1 nanoparticles. An in vitro release study demonstrated that self-assembled C18-SS-EM1 nanoparticles possessed reduction-responsive behavior. In summary, self-assembling C18-SS-EM1 nanoparticles, which integrate the advantages of lipidization, nanoscale characteristics and, labile disulfide bonds, represent a promising strategy for brain delivery of short peptides.


Assuntos
Encéfalo/metabolismo , Nanomedicina , Oligopeptídeos/farmacocinética , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/diagnóstico por imagem , Dicroísmo Circular , Portadores de Fármacos/química , Meia-Vida , Masculino , Camundongos , Nanopartículas/química , Oligopeptídeos/sangue , Oligopeptídeos/química , Espectroscopia de Luz Próxima ao Infravermelho
20.
Expert Opin Drug Saf ; 18(11): 1009-1015, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31478396

RESUMO

Introduction: Therapeutic drug monitoring in oncology is used to prevent major toxicities of selected anticancer agents due to overexposure by individualizing the dose based on a pharmacokinetic target. Areas covered: Numerous studies relating a relation between pharmacokinetic variability and toxicity have been reported since the eighties but very few have been implemented in clinical practice due to a lack of validation and harmonization, logistical constraints and reluctance from oncologists. Following recent recommendations, this paper highlights the current-validated applications of pharmacokinetic monitoring in oncology focusing on the safety of anticancer therapies. Expert opinion: Paradoxically given the oldness of the agents, guidelines of dose adjustment have been recently available for intravenous busulfan, 5-fluorouracil, and high-dose methotrexate. Interestingly, besides the enhancement of tolerability, it applies to potential curative clinical situations. In an era of personalized oncology that integrates complex molecular factors in the treatment of cancer, education is needed for oncologists to show the benefits of this valuable (even old) resource for the safety of patients. Therapeutic drug monitoring for busulfan, 5-fluorouracil and methotrexate will still hold in the future unless more active agents are available in the concerned indications.


Assuntos
Antineoplásicos/administração & dosagem , Monitoramento de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacocinética , Bussulfano/administração & dosagem , Bussulfano/efeitos adversos , Bussulfano/farmacocinética , Relação Dose-Resposta a Droga , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Fluoruracila/farmacocinética , Humanos , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Metotrexato/farmacocinética , Guias de Prática Clínica como Assunto , Medicina de Precisão/métodos
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