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1.
J Nat Prod ; 87(9): 2281-2291, 2024 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-39276089

RESUMO

The phytochemical investigation of Euphorbia desmondii resulted in the isolation of 15 previously undescribed triterpenoids (desmondiins A, C-P) and 8 already described compounds. The structures of the isolated compounds were determined by extensive spectroscopic analyses. The compounds were identified as tirucallane and euphane triterpenes based on 7-keto-8-ene, 11-keto-8-ene, or 7,11-diketo-8-ene skeletons. Additionally, the selective trypanocidal activities of these compounds against Trypanosoma cruzi were evaluated. Desmondiins A, C, D, F, H, and M exhibited IC50 values in the range of 3-5 µM, and selectivity indices between 5-9, against T. cruzi epimastigotes over the host cell (RAW264.7 macrophages). Furthermore, desmondiin A efficiently inhibited amastigote replication in host cells (IC50 = 2.5 ± 0.3 µM), which was comparable to that of the positive control, benznidazole (3.6 ± 0.4 µM). Overall, the isolated euphane and tirucallane triterpenoids could act as antichagasic lead scaffolds.


Assuntos
Euphorbia , Triterpenos , Tripanossomicidas , Trypanosoma cruzi , Euphorbia/química , Triterpenos/farmacologia , Triterpenos/química , Triterpenos/isolamento & purificação , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Trypanosoma cruzi/efeitos dos fármacos , Animais , Camundongos , Estrutura Molecular , Células RAW 264.7
2.
J Nat Prod ; 87(8): 2068-2080, 2024 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-39121346

RESUMO

Continuing our search for bioactive compounds in species from the Juncaceae family, Juncus articulatus was investigated. Ten previously undescribed phenanthrenes─articulins A-J (1-10)─and ten known compounds─juncuenin B, dehydrojuncuenin B, juncatrin B, ensifolins E, F, H, I, K, juncuenin D, and luzulin A (11-20)─along with other compounds, have been isolated and identified. The isolated compounds were evaluated for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, methicillin-susceptible Staphylococcus aureus (MSSA), and methicillin-resistant Staphylococcus aureus (MRSA). Compounds 12 and 14 exhibited the most potent activity against planktonic and sessile MSSA and MRSA with minimum inhibitory concentration (MIC) values of 15.1 µM (12 for both bacterial strains) and 15.3 µM (14 for both bacterial strains). Compounds 15, 17, and 18 also exhibited activity against both strains, although to a lower extent, with MIC values ranging from 30.0 to 56.8 µM. The inhibition of biofilm formation of these compounds was observed at 15.1-114.3 µM. This study elucidates the phenanthrene composition of J. articulatus and the antibacterial effect of these compounds.


Assuntos
Antibacterianos , Biofilmes , Staphylococcus aureus Resistente à Meticilina , Testes de Sensibilidade Microbiana , Fenantrenos , Antibacterianos/farmacologia , Antibacterianos/química , Biofilmes/efeitos dos fármacos , Fenantrenos/farmacologia , Fenantrenos/química , Fenantrenos/isolamento & purificação , Estrutura Molecular , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Pseudomonas aeruginosa/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos
3.
Int J Mol Sci ; 25(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38731937

RESUMO

Due to the favorable features obtained through the incorporation of fluorine atom(s), fluorinated drugs are a group with emerging pharmaceutical importance. As their commercial availability is still very limited, to expand the range of possible candidates, new fluorinated tryptophan analogs were synthesized. Control of enantiopurity during the synthesis procedure requires that highly efficient enantioseparation methods be available. In this work, the enantioseparation of seven fluorinated tryptophans and tryptophan was studied and compared systematically to (i) develop analytical methods for enantioselective separations and (ii) explore the chromatographic features of the fluorotrytophans. For enantioresolution, macrocyclic glycopeptide-based selectors linked to core-shell particles were utilized, applying liquid chromatography-based methods. Application of the polar-ionic mode resulted in asymmetric and broadened peaks, while reversed-phase conditions, together with mobile-phase additives, resulted in baseline separation for all studied fluorinated tryptophans. The marked differences observed between the methanol and acetonitrile-containing eluent systems can be explained by the different solvation abilities of the bulk solvents of the applied mobile phases. Among the studied chiral selectors, teicoplanin and teicoplanin aglycone were found to work effectively. Under optimized conditions, baseline separations were achieved within 6 min. Ionic interactions were semi-quantitatively characterized and found to not influence enantiorecognition. Interestingly, fluorination of the analytes does not lead to marked changes in the chromatographic characteristics of the methanol-containing eluents, while larger differences were noticed when the polar but aprotic acetonitrile was applied. Experiments conducted on the influence of the separation temperature indicated that the separations are enthalpically driven, with only one exception. Enantiomeric elution order was found to be constant on both teicoplanin and teicoplanin aglycone-based chiral stationary phases (L < D) under all applied chromatographic conditions.


Assuntos
Glicopeptídeos , Halogenação , Teicoplanina , Triptofano , Triptofano/química , Triptofano/análogos & derivados , Glicopeptídeos/química , Estereoisomerismo , Teicoplanina/química , Teicoplanina/análogos & derivados , Cromatografia Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Compostos Macrocíclicos/química
4.
Molecules ; 29(17)2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39275023

RESUMO

The reaction between glycine-type aminonaphthol derivatives substituted with 2- or 1-naphthol and indole or 7-azaindole has been tested. Starting from 2-naphthol as a precursor, the reaction led to the formation of ring-closed products, while in the case of a 1-naphthol-type precursor, the desired biaryl ester was isolated. The synthesis of a bifunctional precursor starting from 5-chloro-8-hydroxyquinoline, morpholine, and ethyl glyoxylate via modified Mannich reaction is reported. The formed Mannich base 10 was subjected to give bioconjugates with indole and 7-azaindole. The effect of the aldehyde component and the amine part of the Mannich base on the synthetic pathway was also investigated. In favor of having a preliminary overview of the structure-activity relationships, the derivatives have been tested on cancer and normal cell lines. In the case of bioconjugate 16, as the most powerful scaffold in the series bearing indole and a 5-chloro-8-hydroxyquinoline skeleton, a potent toxic activity against the resistant Colo320 colon adenocarcinoma cell line was observed. Furthermore, this derivative was selective towards cancer cell lines showing no toxicity on non-tumor fibroblast cells.


Assuntos
Antineoplásicos , Indóis , Humanos , Indóis/química , Indóis/farmacologia , Indóis/síntese química , Antineoplásicos/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Linhagem Celular Tumoral , Relação Estrutura-Atividade , Oxiquinolina/química , Oxiquinolina/farmacologia , Metano/química , Metano/análogos & derivados , Estrutura Molecular , Ensaios de Seleção de Medicamentos Antitumorais
5.
Molecules ; 29(14)2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39065005

RESUMO

Phenolic compounds are the main special metabolites of Cyperaceae species from phytochemical, pharmacological, and chemotaxonomical points of view. The present study focused on the isolation, structure determination, and pharmacological investigation of constituents from Carex praecox. Twenty-six compounds, including lignans, stilbenes, flavonoids, megastigmanes, chromenes, and phenylpropanoids, were identified from the methanol extract of the plant. Five of these compounds, namely, carexines A-E, are previously undescribed natural products. All compounds were isolated for the first time from C. praecox. The ACE-inhibitory activity of seven stilbenoid compounds was tested, and (-)-hopeaphenol proved to be the most active (IC50 7.7 ± 0.9 µM). The enzyme-kinetic studies revealed a mixed-type inhibition; therefore, domain-specific studies were also conducted. The in silico docking of (-)-hopeaphenol to the ACE affirmed some favorable interactions. In addition, the antiproliferative and antibacterial effects of some compounds were also evaluated.


Assuntos
Inibidores da Enzima Conversora de Angiotensina , Carex (Planta) , Simulação de Acoplamento Molecular , Compostos Fitoquímicos , Extratos Vegetais , Estilbenos , Estilbenos/química , Estilbenos/farmacologia , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Carex (Planta)/química , Inibidores da Enzima Conversora de Angiotensina/química , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/isolamento & purificação , Humanos , Estrutura Molecular , Proliferação de Células/efeitos dos fármacos , Antibacterianos/farmacologia , Antibacterianos/química , Fenóis
6.
Toxicol Appl Pharmacol ; 470: 116548, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37182749

RESUMO

Nowadays, more and more new synthetic cannabinoids (SCs) appearing on the illicit market present challenges to analytical, forensic, and toxicology experts. For a better understanding of the physiological effect of SCs, the key issue is studying their metabolomic and psychoactive properties. In this study, our validated targeted reversed phase UHPLC-MS/MS method was used for determination of urinary concentration of 5F-MDMB-PICA, 4F-MDMB-BICA, and their primary metabolites. The liquid-liquid extraction procedure was applied for the enrichment of SCs. The pharmacological characterization of investigated SCs were studied by radioligand competition binding and ligand stimulated [35S]GTPγS binding assays. For 5F-MDMB-PICA and 4F-MDMB-BICA, the median urinary concentrations were 0.076 and 0.312 ng/mL. For primary metabolites, the concentration range was 0.029-881.02* ng/mL for 5F-MDMB-PICA-COOH, and 0.396-4579* ng/mL for 4F-MDMB-BICA-COOH. In the polydrug aspect, the 22 urine samples were verified to be abused with 6 illicit drugs. The affinity of the metabolites to CB1R significantly decreased compared to the parent ligands. In the GTPγS functional assay, both 5F-MDMB-PICA and 4F-MDMB-BICA were acting as full agonists, while the metabolites were found as weak inverse agonists. Additionally, the G-protein stimulatory effects of the full agonist 5F-MDMB-PICA and 4F-MDMB-BICA were reduced by metabolites. These results strongly indicate the dose-dependent CB1R-mediated weak inverse agonist effects of the two butanoic acid metabolites. The obtained high concentration of main urinary metabolites of 5F-MDMB-PICA and 4F-MDMB-BICA confirmed the relevance of their routine analysis in forensic and toxicological practices. Based on in vitro binding assays, the metabolites presumably might cause a lower psychoactive effect than parent compounds.


Assuntos
Canabinoides , Espectrometria de Massas em Tandem , Espectrometria de Massas em Tandem/métodos , Agonismo Inverso de Drogas , Guanosina 5'-O-(3-Tiotrifosfato) , Canabinoides/farmacologia
7.
J Nat Prod ; 86(4): 891-896, 2023 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-36932959

RESUMO

Five unusual meroterpenoids based on new carbon skeletons, pauciflorins A-E (1-5), were isolated by multistep chromatographic separations of a methanol extract of the aerial parts of Centrapalus pauciflorus. Compounds 1-3 are derived by the connection of a 2-nor-chromone and a monoterpene unit, whereas 4 and 5 are dihydrochromone-monoterpene adducts with a rarely occurring orthoester functionality. The structures were solved using 1D and 2D NMR, HRESIMS, and single-crystal X-ray diffraction. Pauciflorins A-E were evaluated for antiproliferative activity against human gynecological cancer cell lines, but were inactive (IC50 < 10 µM) in each case.


Assuntos
Cromonas , Monoterpenos , Humanos , Estrutura Molecular , Cromonas/farmacologia , Cristalografia por Raios X , Espectroscopia de Ressonância Magnética
8.
Int J Mol Sci ; 24(19)2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37833970

RESUMO

Kynurenic acid (KYNA), an endogenous neuroprotectant with antiexcitotoxic, antioxidant, and anti-inflammatory effects, is synthesized through the tryptophan-kynurenine (KYN) pathway. We investigated whether brain KYN or KYNA levels were affected by asphyxia in a translational piglet model of hypoxic-ischemic encephalopathy (HIE). We also studied brain levels of the putative blood-brain barrier (BBB) permeable neuroprotective KYNA analogue SZR72, and whether SZR72 or therapeutic hypothermia (TH) modified KYN or KYNA levels. KYN, KYNA, and SZR72 levels were determined using ultra-high-performance liquid chromatography coupled with tandem mass spectrometry in five brain regions 24 h after 20 min of asphyxia in vehicle-, SZR72- and TH-treated newborn piglets (n = 6-6-6) and naive controls (n = 4). Endogenous brain KYN levels (median range 311.2-965.6 pmol/g) exceeded KYNA concentrations (4.5-6.0 pmol/g) ~100-fold. Asphyxia significantly increased cerebral KYN and KYNA levels in all regions (1512.0-3273.9 and 16.9-21.2 pmol/g, respectively), increasing the KYN/Tryptophan-, but retaining the KYNA/KYN ratio. SZR72 treatment resulted in very high cerebral SZR72 levels (13.2-33.2 nmol/g); however, KYN and KYNA levels remained similar to those of the vehicle-treated animals. However, TH virtually ameliorated asphyxia-induced elevations in brain KYN and KYNA levels. The present study reports for the first time that the KYN pathway is altered during HIE development in the piglet. SZR72 readily crosses the BBB in piglets but fails to affect cerebral KYNA levels. Beneficial effects of TH may include restoration of the tryptophan metabolism to pre-asphyxia levels.


Assuntos
Hipotermia , Hipóxia-Isquemia Encefálica , Suínos , Animais , Cinurenina/metabolismo , Triptofano/metabolismo , Ácido Cinurênico/metabolismo , Asfixia , Hipóxia-Isquemia Encefálica/terapia
9.
Int J Mol Sci ; 23(7)2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35408806

RESUMO

Fluorine represents a privileged building block in pharmaceutical chemistry. Diethylaminosulfur-trifluoride (DAST) is a reagent commonly used for replacement of alcoholic hydroxyl groups with fluorine and is also known to catalyze water elimination and cyclic Beckmann-rearrangement type reactions. In this work we aimed to use DAST for diversity-oriented semisynthetic transformation of natural products bearing multiple hydroxyl groups to prepare new bioactive compounds. Four ecdysteroids, including a new constituent of Cyanotis arachnoidea, were selected as starting materials for DAST-catalyzed transformations. The newly prepared compounds represented combinations of various structural changes DAST was known to catalyze, and a unique cyclopropane ring closure that was found for the first time. Several compounds demonstrated in vitro antitumor properties. A new 17-N-acetylecdysteroid (13) exerted potent antiproliferative activity and no cytotoxicity on drug susceptible and multi-drug resistant mouse T-cell lymphoma cells. Further, compound 13 acted in significant synergism with doxorubicin without detectable direct ABCB1 inhibition. Our results demonstrate that DAST is a versatile tool for diversity-oriented synthesis to expand chemical space towards new bioactive compounds.


Assuntos
Ecdisteroides , Flúor , Animais , Catálise , Dietilaminas/química , Ecdisteroides/química , Flúor/química , Camundongos
10.
J Nat Prod ; 84(7): 1870-1881, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34143640

RESUMO

Ecdysteroids act as molting hormones in insects and as nonhormonal anabolic agents and adaptogens in mammals. A wide range of ecdysteroid-containing herbal extracts are available worldwide as food supplements. The aim of this work was to study such an extract as a possible industrial source of new bioactive ecdysteroids. A large-scale chromatographic isolation was performed from an extract of Cyanotis arachnoidea roots. Ten ecdysteroids (1-10) including eight new compounds were isolated and characterized by extensive nuclear magnetic resonance studies. Highly unusual structures were identified, including a H-14ß (1, 2, 4, and 10) moiety, among which a 14ß(H)17ß(H) phytosteroid (1) is reported for the first time. Compounds with an intact side chain (4-10) and 11 other natural or semisynthetic ecdysteroids (11-21) were tested for insect ecdysteroid receptor (EcR) binding activity. Two new compounds, i.e., 14-deoxydacryhainansterone (5) and 22-oxodacryhainansterone (6), showed strong EcR binding activity (IC50 = 41.7 and 380 nM, respectively). Six compounds were identified as EcR agonists and another two as antagonists using a transgenic ecdysteroid reporter gene assay. The present results demonstrate that commercial C. arachnoidea extracts are rich in new, unusual bioactive ecdysteroids. Because of the lack of an authentic plant material, the truly biosynthetic or artifactual nature of these compounds cannot be confirmed.


Assuntos
Commelinaceae/química , Ecdisteroides/química , Fitosteróis/química , Extratos Vegetais/química , Receptores de Esteroides/metabolismo , Animais , Estrutura Molecular , Raízes de Plantas/química , Células Sf9
11.
J Sep Sci ; 44(14): 2735-2743, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33999502

RESUMO

Enantiomers of cationic compounds of pharmaceutical relevance, namely tetrahydro-ß-carboline and 1,2,3,4-tetrahydroisoquinoline analogs, were separated by high-performance liquid chromatography. Separations were performed on Cinchona-alkaloid-based zwitterionic ion exchanger type chiral stationary phases applied as cation exchangers using mixtures of methanol and acetonitrile or tetrahydrofuran as bulk solvent components containing triethylammonium acetate or ammonium acetate as organic salt additives. On the zwitterionic ZWIX(+) and ZWIX(-) columns investigated, retention and enantioseparation of the studied basic analytes were influenced by the nature and concentration of the organic components of the mobile phase. The effect of organic salt additives on the retention behavior of the studied analytes can be described by the stoichiometric displacement model related to the counterion concentration. Investigations on the structure-retention relationships were performed applying different mobile phase systems for the two types of cationic analytes. For the thermodynamic characterization, parameters such as changes in standard enthalpy (Δ(ΔH°)), entropy (Δ(ΔS°)), and free energy (Δ(ΔG°)) were calculated on the basis of van't Hoff plots derived from the ln α versus 1/T curves. In most cases, enthalpy-driven enantioseparations were observed, with a consistent dependence of the calculated thermodynamic parameters on the mobile phase composition. Elution sequences of the studied compounds were determined in all cases.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Alcaloides de Cinchona , Cinchona/química , Cátions/isolamento & purificação , Alcaloides de Cinchona/análise , Alcaloides de Cinchona/química , Preparações Farmacêuticas/isolamento & purificação
12.
Int J Mol Sci ; 22(9)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34062911

RESUMO

Hypoxic-ischemic encephalopathy (HIE) remains to be a major cause of long-term neurodevelopmental deficits in term neonates. Hypothermia offers partial neuroprotection warranting research for additional therapies. Kynurenic acid (KYNA), an endogenous product of tryptophan metabolism, was previously shown to be beneficial in rat HIE models. We sought to determine if the KYNA analog SZR72 would afford neuroprotection in piglets. After severe asphyxia (pHa = 6.83 ± 0.02, ΔBE = -17.6 ± 1.2 mmol/L, mean ± SEM), anesthetized piglets were assigned to vehicle-treated (VEH), SZR72-treated (SZR72), or hypothermia-treated (HT) groups (n = 6, 6, 6; Tcore = 38.5, 38.5, 33.5 °C, respectively). Compared to VEH, serum KYNA levels were elevated, recovery of EEG was faster, and EEG power spectral density values were higher at 24 h in the SZR72 group. However, instantaneous entropy indicating EEG signal complexity, depression of the visual evoked potential (VEP), and the significant neuronal damage observed in the neocortex, the putamen, and the CA1 hippocampal field were similar in these groups. In the caudate nucleus and the CA3 hippocampal field, neuronal damage was even more severe in the SZR72 group. The HT group showed the best preservation of EEG complexity, VEP, and neuronal integrity in all examined brain regions. In summary, SZR72 appears to enhance neuronal activity after asphyxia but does not ameliorate early neuronal damage in this HIE model.


Assuntos
Asfixia Neonatal/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Ácido Cinurênico/análogos & derivados , Neurônios/metabolismo , Animais , Asfixia Neonatal/metabolismo , Asfixia Neonatal/patologia , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patologia , Região CA1 Hipocampal/diagnóstico por imagem , Região CA1 Hipocampal/efeitos dos fármacos , Região CA3 Hipocampal/diagnóstico por imagem , Região CA3 Hipocampal/efeitos dos fármacos , Modelos Animais de Doenças , Eletroencefalografia , Potenciais Evocados Visuais/efeitos dos fármacos , Humanos , Ácido Cinurênico/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Pesquisa Translacional Biomédica
13.
Molecules ; 26(11)2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34205002

RESUMO

Numerous chemical compounds of high practical importance, such as drugs, fertilizers, and food additives are being commercialized as racemic mixtures, although in most cases only one of the isomers possesses the desirable properties. As our understanding of the biological actions of chiral compounds has improved, the investigation of the pharmacological and toxicological properties has become more and more important. Chirality has become a major issue in the pharmaceutical industry; therefore, there is a continuous demand to extend the available analytical methods for enantiomeric separations and enhance their efficiency. Direct liquid chromatography methods based on the application of chiral stationary phases have become a very sophisticated field of enantiomeric separations by now. Hundreds of chiral stationary phases have been commercialized so far. Among these, macrocyclic glycopeptide-based chiral selectors have proved to be an exceptionally useful class of chiral selectors for the separation of enantiomers of biological and pharmacological importance. This review focuses on direct liquid chromatography-based enantiomer separations, applying macrocyclic glycopeptide-based chiral selectors. Special attention is paid to the characterization of the physico-chemical properties of these macrocyclic glycopeptide antibiotics providing detailed information on their applications published recently.


Assuntos
Antibacterianos/química , Glicopeptídeos/química , Compostos Macrocíclicos/química , Cromatografia Líquida , Estrutura Molecular , Fenômenos Físicos , Estereoisomerismo
14.
Molecules ; 26(15)2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34361801

RESUMO

Natural compounds can exist in different forms, where molecules possessing chirality play an essential role in living organisms. Currently, one of the most important tasks of modern analytical chemistry is the enantioseparation of chiral compounds, in particular, the enantiomers of compounds having biological and/or pharmaceutical activity. Whether the task is to analyze environmental or food samples or to develop an assay for drug control, well-reproducible, highly sensitive, stereoselective, and robust methods are required. High-performance liquid chromatography best meets these conditions. Nevertheless, in many cases, gas chromatography, supercritical fluid chromatography, or capillary electrophoresis can also offer a suitable solution. Amino acids, proteins, cyclodextrins, derivatized polysaccharides, macrocyclic glycopeptides, and ion exchangers can serve as efficient selectors in liquid chromatography, and they are quite frequently applied and reviewed. Crown ethers and cyclofructans possessing similar structural characteristics and selectivity in the enantiodiscrimination of different amine compounds are discussed less frequently. This review collects information on enantioseparations achieved recently with the use of chiral stationary phases based on crown ethers or cyclofructans, focusing on liquid chromatographic applications.

15.
Molecules ; 25(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348712

RESUMO

The occurrence of phenanthrenes is limited in nature, with such compounds identified only in some plant families. Phenanthrenes were described to have a wide range of pharmacological activities, and numerous research programs have targeted semisynthetic derivatives of the phenanthrene skeleton. The aims of this study were the phytochemical investigation of Juncus tenuis, focusing on the isolation of phenanthrenes, and the preparation of semisynthetic derivatives of the isolated compounds. From the methanolic extract of J. tenuis, three phenanthrenes (juncusol, effusol, and 2,7-dihydroxy-1,8-dimethyl-5-vinyl-9,10-dihydrophenanthrene) were isolated. Juncusol and effusol were transformed by hypervalent iodine(III) reagent, using a diversity-oriented approach. Four racemic semisynthetic compounds possessing an alkyl-substituted p-quinol ring (1-4) were produced. Isolation and purification of the compounds were carried out by different chromatographic techniques, and their structures were elucidated by means of 1D and 2D NMR, and HRMS spectroscopic methods. The isolated secondary metabolites and their semisynthetic analogues were tested on seven human tumor cell lines (A2780, A2780cis, KCR, MCF-7, HeLa, HTB-26, and T47D) and on one normal cell line (MRC-5), using the MTT assay. The effusol derivative 3, substituted with two methoxy groups, showed promising antiproliferative activity on MCF-7, T47D, and A2780 cell lines with IC50 values of 5.8, 7.0, and 8.6 µM, respectively.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Fenantrenos/química , Fenantrenos/farmacologia , Plantas/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HeLa , Humanos , Células MCF-7 , Fenantrenos/isolamento & purificação , Extratos Vegetais/farmacologia
16.
Biomed Chromatogr ; 32(6): e4202, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29399846

RESUMO

Glycerophospholipids (PLs), as amphipathic small molecules and the main constituents of biological membranes, play an important role in several cellular processes, even though their accurate identification from complex biological samples remains a challenge. In this paper, we report a fast and comprehensive HILIC-ESI-MS method for the analysis of glycerophospholipid classes using high-resolution mass spectrometry in negative mode. The final method enabled the quantitative analysis of 130 endogenous PL species in mouse plasma. The application of the method developed was to find differences of plasma PL composition in a mouse model of anxiety disorder. In the case of four PL classes and 35 PL species, significant differences were observed comparing low anxiety-related behavior with high anxiety-related behavior groups. The most characteristic trend was up-regulation in both the PL classes and PL species, and decreases were only detected in two phosphatidylcholines among 35 species in mice having elevated anxiety.


Assuntos
Transtornos de Ansiedade/sangue , Cromatografia Líquida/métodos , Espectrometria de Massas/métodos , Fosfolipídeos/sangue , Animais , Transtornos de Ansiedade/metabolismo , Modelos Animais de Doenças , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Fosfolipídeos/metabolismo
17.
J Diet Suppl ; 21(4): 462-477, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38165273

RESUMO

Boswellia serrata ole-gum-resin extracts (BSEs) are commonly used as food supplements, especially in osteoarthritis management. The quality standard is established by determining 11-keto-ß-boswellic acid (KBA) and acetyl-11-keto-boswellic acid (AKBA) content using high-performance liquid chromatography (HPLC) or assessing the total boswellic acid (TBA) content by titrimetry. The limited geographical distribution of Boswellia species and increasing industrial demand could increase the risk of adulteration in Boswellia-containing products. In this study, 14 BSEs from commercial sources, used in food supplements, were analyzed in comparison with a USP Reference Standard extract. The KBA and AKBA content was determined by HPLC, whereas the TBA content was determined by titration. Targeted UHPLC-high-resolution mass spectrometry (HRMS) was applied to identify the carboxylic acid content in the samples. The 1H NMR spectra of extracts were also analyzed. Only two products met the criteria for KBA and AKBA content. Although, the TBA content complied with the expected amount, 10 extracts contained citric acid levels of 6-11% even though citric acid is not a cha-racteristic component of BSEs. Our results suggest undeclared addition of citric acid to comply with declared contents of TBA when using titration methods. Incorporation of citric acid to industrial samples - in order to alter the outcomes of the titration analysis - was demonstrated for the first time.


Assuntos
Boswellia , Ácido Cítrico , Suplementos Nutricionais , Extratos Vegetais , Triterpenos , Boswellia/química , Cromatografia Líquida de Alta Pressão/métodos , Extratos Vegetais/análise , Extratos Vegetais/química , Triterpenos/análise , Ácido Cítrico/análise , Suplementos Nutricionais/análise , Espectrometria de Massas/métodos , Contaminação de Medicamentos , Espectroscopia de Ressonância Magnética , Resinas Vegetais/análise
18.
RSC Adv ; 14(31): 22123-22131, 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-39005244

RESUMO

Lactam formation of different KYNA amides and Mannich bases mediated by ortho-quinone methide has been investigated. The efficiency of the two routes of the cyclization process was revealed and the influence of diverse amide side chains was explored. In this regard compounds bearing a tertiary amine function in the amide side chain resulted in the formation of the lactam product, while the formation of dimer derivatives was observed in the case of other KYNA amides. Furthermore, derivatives bearing different substituents on the KYNA B ring were synthesized and their effects on the ring-closure reaction were investigated.

20.
Eur J Pharmacol ; 977: 176718, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38849040

RESUMO

Nimodipine is used to prevent delayed ischemic deficit in patients with aneurysmal subarachnoid hemorrhage (aSAH). Spreading depolarization (SD) is recognized as a factor in the pathomechanism of aSAH and other acute brain injuries. Although nimodipine is primarily known as a cerebral vasodilator, it may have a more complex mechanism of action due to the expression of its target, the L-type voltage-gated calcium channels (LVGCCs) in various cells in neural tissue. This study was designed to investigate the direct effect of nimodipine on SD, ischemic tissue injury, and neuroinflammation. SD in control or nimodipine-treated live mouse brain slices was induced under physiological conditions using electrical stimulation, or by subjecting the slices to hypo-osmotic stress or mild oxygen-glucose deprivation (mOGD). SD was recorded applying local field potential recording or intrinsic optical signal imaging. Histological analysis was used to estimate tissue injury, the number of reactive astrocytes, and the degree of microglia activation. Nimodipine did not prevent SD occurrence in mOGD, but it did reduce the rate of SD propagation and the cortical area affected by SD. In contrast, nimodipine blocked SD occurrence in hypo-osmotic stress, but had no effect on SD propagation. Furthermore, nimodipine prevented ischemic injury associated with SD in mOGD. Nimodipine also exhibited anti-inflammatory effects in mOGD by reducing reactive astrogliosis and microglial activation. The results demonstrate that nimodipine directly inhibits SD, independent of nimodipine's vascular effects. Therefore, the use of nimodipine may be extended to treat acute brain injuries where SD plays a central role in injury progression.


Assuntos
Isquemia Encefálica , Encéfalo , Depressão Alastrante da Atividade Elétrica Cortical , Nimodipina , Animais , Nimodipina/farmacologia , Camundongos , Depressão Alastrante da Atividade Elétrica Cortical/efeitos dos fármacos , Masculino , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Encéfalo/metabolismo , Isquemia Encefálica/tratamento farmacológico , Isquemia Encefálica/patologia , Camundongos Endogâmicos C57BL , Doenças Neuroinflamatórias/tratamento farmacológico , Doenças Neuroinflamatórias/patologia , Microglia/efeitos dos fármacos , Microglia/metabolismo , Microglia/patologia , Bloqueadores dos Canais de Cálcio/farmacologia , Bloqueadores dos Canais de Cálcio/uso terapêutico , Pressão Osmótica/efeitos dos fármacos
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