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1.
Int J Nanomedicine ; 19: 3737-3751, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38699684

RESUMO

Background: Chemo-photodynamic combination therapy has demonstrated significant potential in the treatment of cancer. Triptolide (TPL), a naturally derived anticancer agent, when combined with the photosensitizer Chlorin e6 (Ce6), has shown to provide enhanced anti-tumor benefits. However, the development of stimuli-responsive nanovehicles for the co-delivery of TPL and Ce6 could further enhance the efficacy of this combination therapy. Methods: In this study, we synthesized a pH/ROS dual-responsive mPEG-TK-PBAE copolymer, which contains a pH-sensitive PBAE moiety and a ROS-sensitive thioketal (TK) linkage. Through a self-assembly process, TPL and Ce6 were successfully co-loaded into mPEG-TK-PBAE nanoparticles, hereafter referred to as TPL/Ce6 NPs. We evaluated the pH- and ROS-sensitive drug release and particle size changes. Furthermore, we investigated both the in vitro suppression of cellular proliferation and induction of apoptosis in HepG2 cells, as well as the in vivo anti-tumor efficacy of TPL/Ce6 NPs in H22 xenograft nude mice. Results: The mPEG-TK-PBAE copolymer was synthesized through a one-pot Michael-addition reaction and successfully co-encapsulated both TPL and Ce6 by self-assembly. Upon exposure to acid pH values and high ROS levels, the payloads in TPL/Ce6 NPs were rapidly released. Notably, the abundant ROS generated by the released Ce6 under laser irradiation further accelerated the degradation of the nanosystem, thereby amplifying the tumor microenvironment-responsive drug release and enhancing anticancer efficacy. Consequently, TPL/Ce6 NPs significantly increased PDT-induced oxidative stress and augmented TPL-induced apoptosis in HepG2 cells, leading to synergistic anticancer effects in vitro. Moreover, administering TPL/Ce6 NPs (containing 0.3 mg/kg of TPL and 4 mg/kg of Ce6) seven times, accompanied by 650 nm laser irradiation, efficiently inhibited tumor growth in H22 tumor-bearing mice, while exhibiting lower systemic toxicity. Conclusion: Overall, we have developed a tumor microenvironment-responsive nanosystem for the co-delivery of TPL and Ce6, demonstrating amplified synergistic effects of chemo-photodynamic therapy (chemo-PDT) for hepatocellular carcinoma (HCC) treatment.


Assuntos
Apoptose , Clorofilídeos , Diterpenos , Neoplasias Hepáticas , Camundongos Nus , Fenantrenos , Fotoquimioterapia , Fármacos Fotossensibilizantes , Porfirinas , Espécies Reativas de Oxigênio , Animais , Humanos , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Células Hep G2 , Neoplasias Hepáticas/tratamento farmacológico , Porfirinas/química , Porfirinas/farmacologia , Porfirinas/administração & dosagem , Porfirinas/farmacocinética , Diterpenos/química , Diterpenos/farmacologia , Diterpenos/farmacocinética , Diterpenos/administração & dosagem , Concentração de Íons de Hidrogênio , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/administração & dosagem , Apoptose/efeitos dos fármacos , Camundongos , Carcinoma Hepatocelular/tratamento farmacológico , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Compostos de Epóxi/administração & dosagem , Nanopartículas/química , Ensaios Antitumorais Modelo de Xenoenxerto , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/administração & dosagem , Liberação Controlada de Fármacos , Proliferação de Células/efeitos dos fármacos , Polietilenoglicóis/química , Terapia Combinada
2.
Biomater Adv ; 160: 213852, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636118

RESUMO

Immunotherapy is an emerging approach for the treatment of solid tumors. Although chemotherapy is generally considered immunosuppressive, specific chemotherapeutic agents can induce tumor immunity. In this study, we developed a targeted, acid-sensitive peptide nanoparticle (DT/Pep1) to deliver doxorubicin (DOX) and triptolide (TPL) to breast cancer cells via the enhanced permeability and retention (EPR) effect and the breast cancer-targeting effect of peptide D8. Compared with administration of the free drugs, treatment with the DT/Pep1 system increased the accumulation of DOX and TPL at the tumor site and achieved deeper penetration into the tumor tissue. In an acidic environment, DT/Pep1 transformed from spherical nanoparticles to aggregates with a high aspect ratio, which successfully extended the retention of the drugs in the tumor cells and bolstered the anticancer effect. In both in vivo and in vitro experiments, DT/Pep1 effectively blocked the cell cycle and induced apoptosis. Importantly, the DT/Pep1 system efficiently suppressed tumor development in mice bearing 4T1 tumors while simultaneously promoting immune system activation. Thus, the results of this study provide a system for breast cancer therapy and offer a novel and promising platform for peptide nanocarrier-based drug delivery.


Assuntos
Antineoplásicos , Apoptose , Diterpenos , Doxorrubicina , Peptídeos , Animais , Apoptose/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/química , Doxorrubicina/administração & dosagem , Feminino , Peptídeos/farmacologia , Peptídeos/química , Peptídeos/administração & dosagem , Camundongos , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/administração & dosagem , Linhagem Celular Tumoral , Diterpenos/farmacologia , Diterpenos/química , Diterpenos/administração & dosagem , Imunomodulação/efeitos dos fármacos , Compostos de Epóxi/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/administração & dosagem , Nanopartículas/química , Fenantrenos/farmacologia , Fenantrenos/química , Fenantrenos/administração & dosagem , Fenantrenos/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/imunologia , Neoplasias da Mama/patologia , Sistemas de Liberação de Medicamentos/métodos , Camundongos Endogâmicos BALB C
3.
Arch Biochem Biophys ; 756: 109993, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636691

RESUMO

5,6-Epoxy-cholesterols has been recently revealed to control metabolic pathway in breast cancer, which makes investigating their binding interaction with human serum albumin (HSA) an attractive field of research. The main aim of this article is to examine the binding interaction of 5,6 α-epoxy-cholesterol (5,6 α EC) and 5,6 ß-epoxy-cholesterol (5,6 ß- EC) with HSA using different spectroscopic methods and molecular modeling. These compounds interact with HSA via hydrophobic interactions and hydrogen bonds with binding constants 6.3 × 105 M-1 for 5,6 α-epoxy-cholesterol and 6.9 × 105 M-1 for 5,6 ß-epoxy-cholesterol besides, the mechanism of the interaction can be attributed to static quenching. Circular dichroism data indicated that the α-helical content of HSA increased from 50.5 to 59.8 and 61.1 % after the addition of 5,6 α-ECs and 5,6 ß-EC, respectively, with a ratio of 1:2. Thermodynamic analysis revealed that binding between 5,6-epoxy-cholesterols and HSA is spontaneous and entropy-driven. The molecular docking and esterase-like activity experiments were performed to envision a link between the experimental and theoretical results. The optimal binding site of 5,6-epoxy-cholesterols with HSA was located in subdomain IIA. Moreover, theoretical calculations were performed using the B3LYP function with the 6-311++G (d,p) basis set, indicating the HOMO-LUMO energy gap of 7.874 eV for 5,6 α-epoxy-cholesterol and 7.873 eV for 5,6 ß-epoxy-cholesterol. The obtained findings are assumed to provide basic data for understanding the binding interactions of HSA with oxysterol compounds, which could help explore the pharmacokinetics and pharmacodynamics of oxysterol compounds.


Assuntos
Colesterol , Simulação de Acoplamento Molecular , Ligação Proteica , Albumina Sérica Humana , Humanos , Albumina Sérica Humana/química , Albumina Sérica Humana/metabolismo , Colesterol/metabolismo , Colesterol/química , Termodinâmica , Interações Hidrofóbicas e Hidrofílicas , Sítios de Ligação , Dicroísmo Circular , Ligação de Hidrogênio , Compostos de Epóxi/química , Compostos de Epóxi/metabolismo
4.
J Am Chem Soc ; 146(12): 8456-8463, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38479352

RESUMO

Here we report the first total synthesis of the marine macrolide salarin C, a potent anticancer agent, and demonstrate the biomimetic oxidation-Wasserman rearrangement to access salarin A. This synthesis relies on L-proline catalysis to install a chlorohydrin function that masks the sensitive C16-C17 epoxide and potentially mimics the biosynthesis of these compounds where a related chlorohydrin may yield both THF- and epoxide-containing salarins. Additional and key features of the synthesis include (i) macrocycle formation via ring-closing metathesis, (ii) macrocyclic substrate-controlled epoxidation of the C12-C13 allylic alcohol, and (iii) a late-stage Julia-Kocienski olefination to install the side chain. Importantly, this work provides a platform for the synthesis of other salarins and analogues of these potentially important anticancer natural products.


Assuntos
Antineoplásicos , Cloridrinas , Estereoisomerismo , Macrolídeos/química , Compostos de Epóxi/química
5.
Eur Rev Med Pharmacol Sci ; 27(21): 10181-10203, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37975343

RESUMO

Triptolide, a compound isolated from a Chinese medicinal herb, has potent antitumor, immunosuppressive, and anti-inflammatory properties. Due to its interesting structural features and diverse pharmacological activities, it has attracted great interest by the Society of Organic Chemistry and Pharmaceutical Chemistry. However, its clinical potential is greatly hampered by limited aqueous solubility and oral bioavailability, and multi-organ toxicity. In recent years, various derivatives of Triptolide have made varying degrees of progress in the treatment of inflammatory diseases, autoimmune diseases, and cancer. The most researched and potentially clinically valuable of them were (5R)-5-hydroxytriptolide (LLDT-8), PG490-88Na (F6008), and Minnelide. In this review, we provide an overview of the advancements made in triptolide and several of its derivatives' biological activity, mechanisms of action, and clinical development. We also summarized some prospects for the future development of triptolide and its derivatives. It is hoped to contribute to a better understanding of the progress in this field, make constructive suggestions for further studies of Triptolide, and provide a theoretical reference for the rational development of new drugs.


Assuntos
Imunossupressores , Fenantrenos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Fenantrenos/farmacologia , Fenantrenos/uso terapêutico , Compostos de Epóxi/farmacologia , Compostos de Epóxi/uso terapêutico , Compostos de Epóxi/química
6.
J Med Chem ; 66(21): 14497-14512, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37870431

RESUMO

FR901464 is a cytotoxic natural product that binds splicing factor 3B subunit 1 (SF3B1) and PHD finger protein 5A (PHF5A), the components of the human spliceosome. The amide-containing tetrahydropyran ring binds SF3B1, and it remains unclear how the substituents on the ring contribute to the binding. Here, we synthesized meayamycin D, an analogue of FR901464, and three additional analogues to probe the conformation through methyl scanning. We discovered that the amide-containing tetrahydropyran ring assumes only one of the two possible chair conformations and that methylation of the nitrogen distorts the chair form, dramatically reducing cytotoxicity. Meayamycin D induced alternative splicing of MCL-1, showed strong synergism with venetoclax in drug-resistant lung cancer cells, and was cancer-specific over normal cells. Meayamycin D incorporates an alkyl ether and shows a long half-life in mouse plasma. The characteristics of meayamycin D may provide an approach to designing other bioactive L-shaped molecules.


Assuntos
Neoplasias , Splicing de RNA , Humanos , Animais , Camundongos , Compostos de Epóxi/química , Amidas , Fosfoproteínas/química , Transativadores/metabolismo , Proteínas de Ligação a RNA/metabolismo
7.
Int J Biol Macromol ; 252: 126584, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37648137

RESUMO

Cellulose graft copolymers having well-defined structures could incorporate the characteristics of both the cellulose skeleton and side chains, providing a new method for the preparation functionalised cellulose derivatives. Herein, a series of multifunctional cellulose grafted, alternating 3,4-dihydrocoumarin (DHC) and epoxide (EPO) copolymers (cell-g-P(DHC-alt-EPO)) were prepared in a metal-free DBU/DMSO/CO2 solvent system without adding additional catalyst. Four examples of cell-g-P(DHC-alt-EPO) with tunable thermal and optical properties were synthesized by copolymerization of DHC with styrene oxide (SO), propylene oxide (PO), cyclohexene oxide (CHO) or furfuryl glycidyl ether (FGE) onto cellulose. The nonconjugated cell-g-P(DHC-alt-EPO) showed UV absorption properties with the maximum absorption peak at 282 nm and 295 nm and photoluminescence performance. A clustering-triggered emission mechanism was confirmed and consistent with DFT theoretical calculations. In DMSO solution, the copolymer (DHCSO5) with DP of 11.64 showed ACQ behaviour as the concentration increased. In addition, DHCSO5 had good antioxidant capacity with an instantaneous radical scavenging activity of 2,2-diphenyl-1-picrylhydrazine (DPPH) up to 65 % at a concentration of 40 mg/ ml and increased to 100 % after 30 min. Thus, the multifunctional cell-g-P(DHC-alt-EPO) materials had a variety of potential applications in the fields of fluorescent printing, bio-imaging, UV- shielding and antioxidants.


Assuntos
Dióxido de Carbono , Celulose , Celulose/química , Dióxido de Carbono/química , Dimetil Sulfóxido , Solventes , Polímeros/química , Compostos de Epóxi/química
8.
Chem Res Toxicol ; 36(8): 1409-1418, 2023 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-37477250

RESUMO

Human exposure to known carcinogen 1,3-butadiene (BD) is common due to its high concentrations in automobile exhaust, cigarette smoke, and forest fires, as well as its widespread use in the polymer industry. The adverse health effects of BD are mediated by epoxide metabolites such as 3,4-epoxy-1-butene (EB), which reacts with DNA to form 1-hydroxyl-3-buten-1-yl adducts on DNA nucleobases. EB-derived mercapturic acids (1- and 2-(N-acetyl-l-cysteine-S-yl)-1-hydroxybut-3-ene (MHBMA) and N-acetyl-S-(3,4-dihydroxybutyl)-l-cysteine (DHBMA)) and urinary N7-(1-hydroxyl-3-buten-1-yl) guanine DNA adducts (EB-GII) have been used as biomarkers of BD exposure and cancer risk in smokers and occupationally exposed workers. However, low but significant levels of MHBMA, DHBMA, and EB-GII have been reported in unexposed cultured cells, animals, and humans, suggesting that these metabolites and adducts may form endogenously and complicate risk assessment of butadiene exposure. In the present work, stable isotope labeling in combination with high-resolution mass spectrometry was employed to accurately quantify endogenous and exogenous butadiene metabolites and DNA adducts in vivo. Laboratory rats were exposed to 0.3, 0.5, or 3 ppm of BD-d6 by inhalation, and the amounts of endogenous (d0) and exogenous (d6) DNA adducts and metabolites were quantified in tissues and urine by isotope dilution capillary liquid chromatography/high resolution electrospray ionization tandem mass spectrometry (capLC-ESI-HRMS/MS). Our results reveal that EB-GII adducts and MHBMA originate exclusively from exogenous exposure to BD, while substantial amounts of DHBMA are formed endogenously. Urinary EB-GII concentrations were associated with genomic EB-GII levels in tissues of the same animals. Our findings confirm that EB-GII and MHBMA are specific biomarkers of exposure to BD, while endogenous DHBMA predominates at sub-ppm exposures to BD.


Assuntos
Butadienos , Adutos de DNA , Ratos , Animais , Humanos , Butadienos/química , Marcação por Isótopo , Espectrometria de Massas/métodos , DNA , Acetilcisteína/urina , Biomarcadores/urina , Compostos de Epóxi/química
9.
Int J Mol Sci ; 24(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37047173

RESUMO

Polypropionate units are a common structural feature of many of the natural products in polyketides, some of which have shown a broad range of antimicrobial and therapeutic potential. Polypropionates are composed of a carbon skeleton with alternating methyl and hydroxy groups with a specific configuration. Different approaches have been developed for the synthesis of polypropionates and herein we include, for the first time, all of the epoxide-based methodologies that have been reported over the years by several research groups such as Kishi, Katsuki, Marashall, Miyashita, Prieto, Sarabia, Jung, McDonald, etc. Several syntheses of polypropionate fragments and natural products that employed epoxides as key intermediates have been described and summarized in this review. These synthetic approaches involve enatio- and diastereoselective synthesis of epoxides (epoxy-alcohols, epoxy-amides, and epoxy-esters) and their regioselective cleavage with carbon and/or hydride nucleophiles. In addition, we included a description of the isolation and biological activities of the polypropionates and related natural products that have been synthetized using epoxide-based approaches. In conclusion, the epoxide-based methodologies are a non-aldol alternative approach for the construction of polypropionate.


Assuntos
Produtos Biológicos , Compostos de Epóxi , Compostos de Epóxi/química , Produtos Biológicos/farmacologia , Estereoisomerismo , Carbono/química , Álcoois/química
10.
Molecules ; 28(2)2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36677950

RESUMO

The paper presents the preparation of new ionic liquids based on hexamethylenetetramine with bis(trifluoromethanesulfonyl)imide and dicyanamide anion, which were characterized in detail in terms of their purity (Ion Chromatography) and thermal properties (Differential Scanning Calorimetry), as well as stability. The obtained substances were used to develop curing systems with ethylene glycol, which were successfully tested for their application with bisphenol A diglycidyl ether molecule. In addition, the curing process and its relationship to the structure of the ionic liquid are characterized in detail. The research showed that hexamethylenetetramine-based new ionic liquids can be successfully designed using well-known and simple synthetic methods-the Delepine reaction. Moreover, attention was paid to their stability, related limitations, and the application of hexamethylenetetramine-based ionic liquids in epoxy-curing systems.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Metenamina , Etilenoglicol , Compostos de Epóxi/química
11.
Se Pu ; 40(8): 730-735, 2022 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-35903840

RESUMO

A polymer-based strong anion stationary phase modified by quaternary ammoniated allyl glycidyl ether (AGE) for ion chromatography (IC) was developed. It was prepared by surface copolymerization between AGE and the pedant double bonds associated with hydrolyzed poly(glycidylmethacrylate-divinylbenzene) (GMA-DVB) substrate, followed by quaternization with N,N-methyldiethanolamine (a tertiary amine, MDEA). The synthesis conditions were optimized, including the type of organic tertiary amines (MDEA, N,N-dimethylethanolamine, trimethylamine), substrate hydrolysis, the amount of monomer and initiator, reaction temperature and reaction time. The obtained anion stationary phase was characterized by scanning electron microscope and elemental analysis. MDEA was observed to be the best quaternization reagent since the anion exchanger obtained by such reagent showed good separation and suitable retention time towards model inorganic anions. The resulting reason probably lies in higher hydrophilicity of MDEA relative the other two ones. The use of rich epoxy groups of GMA-DVB to introduce the functional groups was commonly used in many previous reports. Here the epoxy groups were firstly hydrolyzed to be diol groups and the pendant double bonds onto the surface of GMA-DVB particles were used to graft AGE. The data achieved indicated that the use of hydrolyzed GMA-DVB substrate would be helpful to reduce anion exchange capacity and unwanted non-ion exchange interaction, in which the rich epoxy groups were converted to hydroxy groups. More important, the obtained anion exchanger after hydrolytic treatment could offer a significantly reduction of retention time (~68%) and a ~1.67-fold higher plate count (take Br- as an example). The apparent capacity of the phase was computed to be 264 µmol/g by content of N data and its effective capacity was measured to be 98.5 µmol/column by the breakthrough curve method. Under the optimal chromatographic conditions, the obtained stationary phase showed baseline separation of seven common inorganic anions in less than 13 min using carbonate-bicarbonate mixed eluent, exhibiting high separation efficiency and peak shape, e. g. 49000 plate/m and 38000 plate/m of the theoretical plate counts respectively for chloride and nitrate, and their asymmetric factor were 1.3 and 1.4. These can be comparable or slightly higher than those of commercial columns. The fitted equation of the eluent concentration and the retention factors of model anions was proved that ion exchange model dominates the retention mechanism of the anion stationary phase. This offers a simple way to prepare anion exchanger and to manipulate anion exchange capacity. The utility of the obtained anion exchanger has been demonstrated to the analysis of tap water.


Assuntos
Compostos de Epóxi , Ânions , Cromatografia por Troca Iônica/métodos , Compostos de Epóxi/química , Interações Hidrofóbicas e Hidrofílicas
12.
Molecules ; 27(12)2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35744811

RESUMO

Triptolide (TP) is a potential drug candidate for the treatment of cancer, but its use was hampered by its systemic toxicity and poor water solubility. Hence, a TP-CSO prodrug was synthesized by conjugating TP to chitosan oligosaccharide (CSO), and characterized by 1H NMR, FTIR, DSC and XRD analyses. The TP-CSO containing about 4 wt% of TP exhibited excellent water solubility (15 mg/mL) compared to TP (0.017 mg/mL). Compared with TP, the pharmacokinetics of the conjugate after oral administration showed a three-fold increase in the half-life in the blood circulation and a 3.2-fold increase in AUC (0-∞). The orally administered TP-CSO could more effectively inhibit tumor progression but with much lower systemic toxicity compared with TP, indicating significant potential for further clinical trials. In conclusion, CSO-based conjugate systems may be useful as a platform for the oral delivery of other sparingly soluble drugs.


Assuntos
Quitosana , Diterpenos , Neoplasias Pancreáticas , Fenantrenos , Pró-Fármacos , Quitosana/química , Diterpenos/química , Compostos de Epóxi/química , Compostos de Epóxi/uso terapêutico , Humanos , Fenantrenos/química , Fenantrenos/uso terapêutico , Pró-Fármacos/uso terapêutico , Água , Neoplasias Pancreáticas
13.
Drug Des Devel Ther ; 16: 521-531, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35250264

RESUMO

INTRODUCTION: Acrylamide is a genotoxic substance that can be found in cigarette smoke. Acrylamide is metabolized by the CYP2E1 enzyme in the body to form glycidamides, an epoxide that is reactive to DNA and can form carcinogenic adducts. Therefore, exposure to acrylamide can potentially cause cancer. This study aims to analyze the levels of acrylamide and glycidamide in dried blood spot samples of smokers using propanamide as an internal standard and non-smokers as the control subjects. METHODS: Dried blood spot samples were extracted using the protein precipitation method and then analyzed by liquid chromatography-tandem mass spectrometry. Mass detection was performed using positive type electro spray ionization and multiple reaction monitoring type with m/z 72.0>55.02 for acrylamide, 88.1>45.0 for glycidamide, and 74.0>57.1 for propanamide as the internal standard. RESULTS: Acrylamide and glycidamide levels in the dried blood spot sample of smokers ranged between 3.91 -10.25 µg/mL and 1.006-3.58 µg/mL, respectively. Data of the non-smokers on acrylamide and glycidamide levels were 0.75-3.16 µg/mL and 0-0.91 µg/mL. DISCUSSION: The significant value of acrylamide and glycidamide between smokers and non-smokers was p < 0.05, which showed that there is a significant difference between acrylamide and glycidamide concentration in smokers and non-smoker subjects. The results of this study suggest that dried blood spots can be used to determine acrylamide and glycidamide levels in humans. Theoretically, acrylamide and glycidamide concentration should correlate to each other; however in reality, there are other factors (such as CYP2E1 polymorphism, dietary intake, etc) that can cause variation in their respective concentration.


Assuntos
Acrilamida , Espectrometria de Massas em Tandem , Acrilamida/análise , Acrilamida/metabolismo , Acrilamida/toxicidade , Cromatografia Líquida de Alta Pressão/métodos , Compostos de Epóxi/química , Humanos , Fumantes , Espectrometria de Massas em Tandem/métodos
14.
Mikrochim Acta ; 189(3): 92, 2022 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-35132465

RESUMO

A novel coating based on hybrid monolith with metal-organic framework (MOF) onto conventional Teflon-coated magnetic stir bars was developed. For this purpose, the external surface of the Teflon stir bar was firstly vinylized in order to immobilize a glycidyl methacrylate (GMA)-based polymer onto the magnet. Then, an amino-modified MOF of type MIL-101 (NH2-MIL-101(Al)) was covalently attached to the GMA-based monolith. After the synthesis process, several parameters affecting extraction of target estrogens by stir bar sorptive extraction (SBSE) including pH, ionic strength, extraction time, stirring rate, desorption solvent, and desorption time were also investigated. The resulting hybrid monolith was evaluated as SBSE sorbent for extraction of three estrogens (estrone, 17ß-estradiol, estriol) and synthetic 17ß-ethinylestradiol from water and human urine samples followed by HPLC with fluorescence detection (excitation and emission wavelengths, 280 and 310 nm, respectively). Under the optimal experimental conditions, the analytical figures of the method were established, achieving satisfactory limits of detection in the range of 0.015-0.58 µg L-1, recovery results ranging from 70 to 95% with RSD less than 6%, and precision values (intra- and inter-extraction units) below 6%.


Assuntos
Disruptores Endócrinos/análise , Compostos de Epóxi/química , Estrogênios/análise , Estruturas Metalorgânicas/química , Metacrilatos/química , Poluentes Químicos da Água/análise , Cromatografia Líquida , Humanos
15.
Molecules ; 27(3)2022 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-35164324

RESUMO

Ardisiacrispin D-F (1-3), three new 13,28 epoxy bridged oleanane-type triterpenoid saponins, together with four known analogues (4-7) were isolated from the roots of Ardisia crispa. The structures of 1-7 were elucidated based on 1D and 2D-NMR experiments and by comparing their spectroscopic data with values from the published literatures. Ardisiacrispin D-F (1-3) are first examples that the monosaccharide directly linked to aglycone C-3 of triterpenoid saponins in genus Ardisia are non-arabinopyranose. In the present paper, all compounds are evaluated for the cytotoxicity against three cancer cell lines (HeLa, HepG2 and U87 MG) in vitro. The results show that compounds 1, 4 and 6 exhibited significant cytotoxicity against Hela and U87 MG cells with IC50 values in the range of 2.2 ± 0.6 to 9.5 ± 1.8 µM. The present investigation suggests that roots of A. crispa could be a potential source of natural anti-tumor agents and their triterpenoid saponins might be responsible for cytotoxicity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ardisia/química , Neoplasias/tratamento farmacológico , Extratos Vegetais/farmacologia , Raízes de Plantas/química , Saponinas/química , Triterpenos/química , Compostos de Epóxi/química , Humanos , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Células Tumorais Cultivadas
16.
Chem Res Toxicol ; 35(2): 283-292, 2022 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-35044764

RESUMO

Despite the increasing popularity of e-cigarettes, their long-term health effects remain unknown. In animal models, exposure to e-cigarette has been reported to result in pulmonary and cardiovascular injury, and in humans, the acute use of e-cigarettes increases heart rate and blood pressure and induces endothelial dysfunction. In both animal models and humans, cardiovascular dysfunction associated with e-cigarettes has been linked to reactive aldehydes such as formaldehyde and acrolein generated in e-cigarette aerosols. These aldehydes are known products of heating and degradation of vegetable glycerin (VG) present in e-liquids. Here, we report that in mice, acute exposure to a mixture of propylene glycol:vegetable glycerin (PG:VG) or to e-cigarette-derived aerosols significantly increased the urinary excretion of acrolein and glycidol metabolites─3-hydroxypropylmercapturic acid (3HPMA) and 2,3-dihydroxypropylmercapturic acid (23HPMA)─as measured by UPLC-MS/MS. In humans, the use of e-cigarettes led to an increase in the urinary levels of 23HPMA but not 3HPMA. Acute exposure of mice to aerosols derived from PG:13C3-VG significantly increased the 13C3 enrichment of both urinary metabolites 13C3-3HPMA and 13C3-23HPMA. Our stable isotope tracing experiments provide further evidence that thermal decomposition of vegetable glycerin in the e-cigarette solvent leads to generation of acrolein and glycidol. This suggests that the adverse health effects of e-cigarettes may be attributable in part to these reactive compounds formed through the process of aerosolizing nicotine. Our findings also support the notion that 23HPMA, but not 3HPMA, may be a relatively specific biomarker of e-cigarette use.


Assuntos
Acroleína/química , Sistemas Eletrônicos de Liberação de Nicotina , Compostos de Epóxi/química , Aromatizantes/química , Propanóis/química , Acroleína/metabolismo , Acroleína/urina , Aerossóis/química , Animais , Biomarcadores , Cromatografia Líquida de Alta Pressão , Compostos de Epóxi/metabolismo , Compostos de Epóxi/urina , Aromatizantes/metabolismo , Masculino , Espectrometria de Massas , Camundongos , Camundongos Endogâmicos C57BL , Propanóis/metabolismo , Propanóis/urina , Solventes , Vaping
17.
Rapid Commun Mass Spectrom ; 36(6): e9245, 2022 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-34939243

RESUMO

RATIONALE: Acrylamide is classified as a probable human carcinogen that is metabolised to glycidamide, which can covalently bind to DNA. The aim of this study was to investigate the formation of N7-glycidamide guanine (N7-GA-Gua) adducts in human blood DNA following exposure to acrylamide present in carbohydrate-rich foods as part of the normal human diet. METHODS: Lymphocyte DNA was extracted from blood samples obtained from healthy human volunteers. Following thermal depurination of the DNA samples, N7-GA-Gua adducts were quantified using a validated liquid chromatography/tandem mass spectrometry (LC/MS/MS) method incorporating a stable isotope labelled internal standard. Estimated dietary acrylamide intake was recorded by completion of food frequency questionnaires for the 24 hours prior to volunteer blood donation. RESULTS: An LC/MS/MS method was validated with a limit of detection of 0.25 fmol and a lower limit of quantitation of 0.50 fmol on column. N7-GA-Gua adducts were detected in human blood DNA with the levels ranging between 0.3 to 6.3 adducts per 108 nucleotides. The acrylamide intake was calculated from the food frequency questionnaires ranging between 20.0 and 78.6 µg. CONCLUSIONS: Identification and quantification of N7-GA-Gua adducts in the blood DNA of healthy volunteers suggests that dietary acrylamide exposure may lead to the formation of DNA adducts. This important finding warrants further investigation to ascertain a correlation between environmental/dietary acrylamide exposure and levels of DNA adducts.


Assuntos
Acrilamida/metabolismo , Cromatografia Líquida/métodos , Adutos de DNA/química , DNA/química , Exposição Dietética/efeitos adversos , Compostos de Epóxi/química , Guanina/química , Espectrometria de Massas em Tandem/métodos , Humanos , Linfócitos/química
18.
Molecules ; 26(24)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34946641

RESUMO

As part of our search for bioactive metabolites from understudied marine microorganisms, the new chlorinated metabolite chlovalicin B (1) was isolated from liquid cultures of the marine basidiomycete Digitatispora marina, which was collected and isolated from driftwood found at Vannøya, Norway. The structure of the novel compound was elucidated by spectroscopic methods including 1D and 2D NMR and analysis of HRMS data, revealing that 1 shares its molecular scaffold with a previously isolated compound, chlovalicin. This represents the first compound isolated from the Digitatispora genus, and the first reported fumagillin/ovalicin-like compound isolated from Basidiomycota. Compound 1 was evaluated for antibacterial activities against a panel of five bacteria, its ability to inhibit bacterial biofilm formation, for antifungal activity against Candida albicans, and for cytotoxic activities against malignant and non-malignant human cell lines. Compound 1 displayed weak cytotoxic activity against the human melanoma cell line A2058 (~50% survival at 50 µM). No activity was detected against biofilm formation or C. albicans at 50 µM, or against bacterial growth at 100 µM nor against the production of cytokines by the human acute monocytic leukemia cell line THP-1 at 50 µM.


Assuntos
Antibacterianos , Antifúngicos , Bactérias/crescimento & desenvolvimento , Basidiomycota/química , Candida albicans/crescimento & desenvolvimento , Sesquiterpenos , Antibacterianos/química , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Antifúngicos/farmacologia , Cicloexanonas/química , Cicloexanonas/isolamento & purificação , Cicloexanonas/farmacologia , Compostos de Epóxi/química , Compostos de Epóxi/isolamento & purificação , Compostos de Epóxi/farmacologia , Sesquiterpenos/química , Sesquiterpenos/isolamento & purificação , Sesquiterpenos/farmacologia
19.
J Nanobiotechnology ; 19(1): 409, 2021 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-34876139

RESUMO

BACKGROUND: Attenuating inflammatory response and relieving pain are two therapeutic therapeutical goals for rheumatoid arthritis (RA). Anti-inflammatory and analgesic drugs are often associated with many adverse effects due to nonspecific distribution. New drug delivery systems with practical targeting ability and other complementary strategies urgently need to be explored. To achieve this goal, an acupoint drug delivery system that can target deliver anti-inflammatory drugs and simulate acupuncture in relieving pain was constructed, which can co-deliver triptolide (TP) and 2-chloro-N (6)-cyclopentyl adenosine (CCPA). RESULTS: We have successfully demonstrated that acupoint nanocomposite hydrogel composed of TP-Human serum album nanoparticles (TP@HSA NPs) and CCPA could effectively treat RA. The result shows that CCPA-Gel can enhance analgesic effects specifically at the acupoint, while the mechanical and thermal pain threshold was 4.9 and 1.6 times compared with non-acupoint, respectively, and the nanocomposite gel further enhanced. Otherwise, the combination of acupoint and nanocomposite hydrogel exerted synergetic improvement of inflammation, bone erosion, and reduction of systemic toxicity. Furthermore, it could regulate inflammatory factors and restore the balance of Th17/Treg cells, which provided a novel and effective treatment strategy for RA. Interestingly, acupoint administration could improve the accumulation of the designed nanomedicine in arthritic paws (13.5% higher than those in non-acupoint at 48 h), which may explain the better therapeutic efficiency and low toxicity. CONCLUSION: This novel therapeutic approach-acupoint nanocomposite hydrogel, builds a bridge between acupuncture and drugs which sheds light on the combination of traditional and modern medicine.


Assuntos
Pontos de Acupuntura , Anti-Inflamatórios , Artrite Reumatoide/metabolismo , Diterpenos , Nanogéis , Fenantrenos , Terapia por Acupuntura , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacocinética , Anti-Inflamatórios/farmacologia , Comportamento Animal/efeitos dos fármacos , Preparações de Ação Retardada , Diterpenos/química , Diterpenos/farmacocinética , Diterpenos/farmacologia , Sistemas de Liberação de Medicamentos , Compostos de Epóxi/química , Compostos de Epóxi/farmacocinética , Compostos de Epóxi/farmacologia , Humanos , Masculino , Nanomedicina , Fenantrenos/química , Fenantrenos/farmacocinética , Fenantrenos/farmacologia , Ratos , Ratos Sprague-Dawley
20.
J Nanobiotechnology ; 19(1): 381, 2021 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-34802453

RESUMO

BACKGROUND: The prognosis of patients with advanced gastric cancer (GC) remains unsatisfactory owing to distant metastasis and resistance to concurrent systemic therapy. Cancer-associated fibroblasts (CAFs), as essential participators in the tumor microenvironment (TME), play a vital role in tumor progression. Thus, CAFs-targeting therapy is appealing for remodeling TME and sensitizing GC to conventional systemic therapy. METHODS: Amphiphilic SN38 prodrug polymeric micelles (PSN38) and encapsulated the hydrophobic esterase-responsive prodrug of Triptolide (TPL), triptolide-naphthalene sulfonamide (TPL-nsa), were synthesized to form PSN38@TPL-nsa nanoparticles. Then, CAFs were isolated from fresh GC tissues and immortalized. TPL at low dose concentration was used to investigate its effect on CAFs and CAFs-induced GC cells proliferation and migration. The synergistic mechanism and antitumor efficiency of SN38 and TPL co-delivery nanoparticle were investigated both in vitro and in vivo. RESULTS: Fibroblast activation protein (FAP), a marker of CAFs, was highly expressed in GC tissues and indicated poorer prognosis. TPL significantly reduced CAFs activity and inhibited CAFs-induced proliferation, migration and chemotherapy resistance of GC cells. In addition, TPL sensitized GC cells to SN38 treatment through attenuated NF-κB activation in both CAFs and GC cells. PSN38@TPL-nsa treatment reduced the expression of collagen, FAP, and α-smooth muscle actin (α-SMA) in tumors. Potent inhibition of primary tumor growth and vigorous anti-metastasis effect were observed after systemic administration of PSN38@TPL-nsa to CAFs-rich peritoneal disseminated tumor and patient-derived xenograft (PDX) model of GC. CONCLUSION: TPL suppressed CAFs activity and CAFs-induced cell proliferation, migration and chemotherapy resistance to SN38 of GC. CAFs-targeted TPL and SN38 co-delivery nanoparticles exhibited potent efficacy of antitumor and reshaping TME, which was a promising strategy to treat advanced GC.


Assuntos
Antineoplásicos , Micelas , Pró-Fármacos , Neoplasias Gástricas/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Fibroblastos Associados a Câncer/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Diterpenos/farmacocinética , Diterpenos/farmacologia , Sinergismo Farmacológico , Compostos de Epóxi/química , Compostos de Epóxi/farmacocinética , Compostos de Epóxi/farmacologia , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Fenantrenos/química , Fenantrenos/farmacocinética , Fenantrenos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacocinética , Pró-Fármacos/farmacologia , Microambiente Tumoral/efeitos dos fármacos
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