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1.
Phytochem Anal ; 31(1): 57-67, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31286597

RESUMO

INTRODUCTION: In European traditional medicine, common ash leaf infusion is recommended by European Medicines Agency to treat minor articular pain and to increase the amount of urine for flushing minor urinary complaints. However, a comprehensive ultra-high-performance liquid chromatography diode array detector electrospray ionisation tandem mass spectrometry (UHPLC-DAD-ESI-MS/MS) analysis of this pharmacopeial plant material has never been performed. Moreover, the number of biological and pharmacological investigations proving the usefulness of this plant material in recommended traditional uses is surprisingly small. OBJECTIVE: Phytochemical profiling of ash leaf samples from different commercial and natural sources and the determination of the in vitro effects on inflammatory mediators in a model of human neutrophils. METHODS: Ash leaf samples were characterised by total hydroxycinnamic acid content and by high-performance thin layer chromatography (HPTLC), UHPLC-DAD-ESI-MS/MS methods. The effects of leaf infusions on reactive oxygen species (ROS), tumor necrosis factor (TNF-α), interleukin 8 (IL-8), interleukin 1ß (IL-1ß), and monocyte chemoattractant protein 1 (MCP-1) production by neutrophils were measured using luminol-dependent chemiluminescence and enzyme-linked immunosorbent assay (ELISA). RESULTS: In ash leaf samples 64 compounds were identified or partly identified together with four unknown compounds. The major compounds detected belong to different structural groups, including phenolic acid derivatives, phenylethanoids, flavonoids, iridoids, secoiridoids and lignans. The major compounds detected in ash samples were chlorogenic acid, quercetin-3-O-rutinoside, verbascoside, oleuropein and ligstroside. However, one sample contained coumarin derivatives. This finding suggested adulteration with other Fraxinus species and/or plant parts. All infusions were able to inhibit ROS, cytokine and chemokine production. CONCLUSIONS: The performed phytochemical and biological analyses contribute to the knowledge about this pharmacopeial plant material and supports its traditional use to treat minor inflammatory complaints.


Assuntos
Fraxinus , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Fina , Flavonoides , Humanos , Mediadores da Inflamação , Extratos Vegetais , Espectrometria de Massas por Ionização por Electrospray
2.
Molecules ; 24(8)2019 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-31022860

RESUMO

Carpesium divaricatum Sieb. & Zucc. has a long history of use as both a medicinal and a food plant. However, except for terpenoids, its chemical constituents have remained poorly investigated. The composition of hydroalcoholic extract from aerial parts of C. divaricatum was analyzed by HPLC-DAD-MSn, revealing the presence of numerous caffeic acid derivatives that were formerly unknown constituents of the plant. In all, 17 compounds, including commonly found chlorogenic acids and rarely occurring butyryl and methylbutyryl tricaffeoylhexaric acids, were tentatively identified. Fractionation of lipophilic extract from cultivated shoots led to the isolation of 12-oxo-phytodienoic acid (12-OPDA), which is a newly identified constituent of the plant. The compound, at concentrations of 0.5, 1.0, and 2.5 µM, significantly reduced IL-8, IL-1ß, TNFα, and CCL2 excretion by lipopolysaccharide (LPS)-stimulated human neutrophils. Reactive oxygen species (ROS) production induced by f-MLP was also significantly diminished in the neutrophils pretreated by 12-OPDA. The newly identified constituents of the plant seem to be partly responsible for its pharmacological activity and elevate the value of C. divaricatum as a potential functional food.


Assuntos
Asteraceae/química , Ácidos Cafeicos/química , Ácido Clorogênico/química , Ácidos Graxos Insaturados/química , Ácidos Cafeicos/isolamento & purificação , Ácidos Cafeicos/farmacologia , Quimiocina CCL2/genética , Ácido Clorogênico/isolamento & purificação , Cromatografia Líquida de Alta Pressão , Ácidos Graxos Insaturados/isolamento & purificação , Ácidos Graxos Insaturados/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-8/genética , Lipopolissacarídeos/farmacologia , Neutrófilos/efeitos dos fármacos , Componentes Aéreos da Planta/química , Brotos de Planta/química , Espécies Reativas de Oxigênio/química , Fator de Necrose Tumoral alfa/genética
3.
J Nat Prod ; 82(2): 375-385, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30653318

RESUMO

During chronic inflammation, neutrophils acting locally as effector cells not only activate antibacterial defense but also promote the inflammatory response. Interleukin 8 (IL-8), the main cytokine produced by activated neutrophils, positively correlates with the severity of respiratory tract diseases. By screening European plants traditionally used for treating respiratory tract diseases, we found that extracts of aerial parts of Eupatorium cannabinum inhibit IL-8 release from neutrophils. Using bioassay-guided fractionation, we identified five sesquiterpene lactones, eupatoriopicrin (1), 5'-deoxyeupatoriopicrin (2), hiyodorilactone A (3), 3-hydroxy-5'- O-acetyleupatoriopicrin = hiyodorilactone D (4), and hiyodorilactone B (5), that efficiently (IC50 < 1 µM) inhibited IL-8 and TNF-α release in lipopolysaccharide (LPS)-stimulated human neutrophils. Moreover, all these sesquiterpene lactones suppressed the adhesion of human neutrophils to an endothelial monolayer by downregulating the expression of the ß2 integrin CD11b/CD18 on the neutrophil surface. Furthermore, eupatoriopicrin efficiently suppressed LPS-induced phosphorylation of p38 MAPK and ERK and attenuated neutrophil infiltration in the thioglycolate-induced peritonitis model in mice. Altogether, these results demonstrate the potential of the sesquiterpene lactone eupatoriopicrin as a lead substance for targeting inflammation.


Assuntos
MAP Quinases Reguladas por Sinal Extracelular/antagonistas & inibidores , Interleucina-8/antagonistas & inibidores , Neutrófilos/efeitos dos fármacos , Sesquiterpenos/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Apoptose/efeitos dos fármacos , Antígenos CD18/antagonistas & inibidores , Células Cultivadas , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células Endoteliais da Veia Umbilical Humana/efeitos dos fármacos , Células Endoteliais da Veia Umbilical Humana/fisiologia , Humanos , Interleucina-8/biossíntese , Neutrófilos/fisiologia , Extratos Vegetais/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Sesquiterpenos/metabolismo , Fator de Necrose Tumoral alfa/biossíntese
4.
Chem Biodivers ; 15(11): e1800269, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30193010

RESUMO

In an initial screening, the dichloromethane extract from the leaves of Melodorum fruticosum showed distinct inhibitory effects on the release of interleukin-8 (IL-8) in human neutrophils. Therefore, the aim of the present study was the phytochemical and pharmacological investigation of this extract, to better understand which compounds might be responsible for the anti-inflammatory effect. Phytochemical analysis led to the isolation of 12 known compounds and two new natural products, 5-hydroxy-6-(2-hydroxybenzyl)-4',7-dimethoxyflavanone (13) and 2',4'-dihydroxy-3'-(2-hydroxybenzyl)-4,6'-dimethoxychalcone (14). The influence of the isolated compounds on the production and release of the pro-inflammatory factors IL-8, tumor necrosis factor alpha (TNF-α), reactive oxygen species (ROS), and adhesion molecules (CD62L and CD11b) in human neutrophils was evaluated. Three constituents, melodamide A, 2',4'-dihydroxy-4,6'-dimethoxychalcone, and 2',6'-dihydroxy-4'-methoxychalcone, showed significant inhibition of IL-8 release (IC50 =6.6, 8.6, and 11.6 µm, respectively) and TNF-α production (IC50 =4.5, 13.3, and 6.2 µm, respectively).


Assuntos
Annonaceae/química , Anti-Inflamatórios não Esteroides/farmacologia , Neutrófilos/efeitos dos fármacos , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Antígeno CD11b/antagonistas & inibidores , Antígeno CD11b/metabolismo , Relação Dose-Resposta a Droga , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Interleucina-8/antagonistas & inibidores , Interleucina-8/metabolismo , Selectina L/antagonistas & inibidores , Selectina L/metabolismo , Neutrófilos/metabolismo , Folhas de Planta/química , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo
5.
Front Pharmacol ; 9: 401, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29740324

RESUMO

Aim of the study: Taking into account that overactivated leukocytes are an important factor in the development of many chronic diseases, we investigated the activity of phytochemically characterized (HPLC-DAD-MSn) extracts from forsythia leaves and flowers on the pro- and anti-inflammatory functions of leukocytes (effects on IL-1ß, IL-8, TNF-α, and TGFß release) and their adherence to endothelial cells. Using bio-guided fractionation, we isolated the active compounds and determined their biological activity, and we included the positive control quercetin. Methods: The effect on IL-1ß, TNF-α, IL-8, and TGF-α production by leukocytes was measured by enzyme-linked immunosorbent assay (ELISA). The surface expression of adhesion molecules was analyzed with flow cytometry, and the neutrophil attachment to the endothelial cells was assessed fluorimetrically. The effects on p38MAPK, ERK1/2 and JNK phosphorylation were determined using western blots. Results: Leaf extracts had the effect of decreasing TNF-α production in neutrophils and monocyte/macrophage cells. The bio-guided fractionation led to the isolation of the following lignan aglycones: (+)-pinoresinol, (+)-epipinoresinol, (-)-matairesinol, (+)-phillygenin, and (-)-arctigenin. Only phillygenin was able to stimulate the anti-inflammatory function of macrophages by inducing TGF-ß release and IL-10 receptor surface expression. Arctigenin, phillygenin, and a metabolite produced by the gut microbiota, enterolactone, decreased TNF-α and IL-1ß production and neutrophil adhesion to endothelial cells, probably by attenuating the p38 and ERK kinase pathways. Conclusion:Forsythia x intermedia is a valuable source of active lignans, which may be potential candidates for treating inflammatory diseases that are associated with the excessive production of cytokines such as TNF-α and IL-1ß.

6.
Front Pharmacol ; 9: 349, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29695965

RESUMO

Aim of the study: The aim of the present study was to investigate the effects of phytochemically characterized extracts connected with the traditional use (infusions and ethanolic extracts) of different parts of Syringa vulgaris (common lilac) on the pro-inflammatory functions of neutrophils. Active compounds were isolated from the most promising extract(s) using bioassay-guided fractionation, and their activity and molecular mechanisms of action were determined. Methods: The extracts were characterized using a HPLC-DAD- MSn method. The effects on ROS, MMP-9, TNF-α, IL-8, and MCP-1 production by neutrophils were measured using luminol-dependent chemiluminescence and enzyme-linked immunosorbent assay (ELISA) methods. The effects on p38MAPK, ERK1/2, JNK phosphorylation, and NF-kB p65 translocation were determined using western blots. Results: The major compounds detected in the extracts and infusions belong to structural groups, including caffeic acid derivatives, flavonoids, and iridoids. All extracts and infusions were able to significantly reduce ROS and IL-8 production. Bioassay-guided fractionation led to the isolation of the following secoiridoids: 2″-epiframeroside, oleonuezhenide, oleuropein, ligstroside, neooleuropein, hydroxyframoside, and framoside. Neooleuropein appeared to be the most active compound in the inhibition of cytokine production by attenuating the MAP kinase pathways. Conclusion: The present study demonstrated that common lilac, which is a traditionally used medicinal plant in Europe, is a valuable source of active compounds, especially neooleuropein.

7.
Anal Chem ; 88(5): 2877-83, 2016 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-26813026

RESUMO

The cycling performance and in operando gas analysis of LiNi0.5Mn1.5O4 (LNMO)/graphite cells with reasonably high loading, containing a "standard" carbonate-based electrolyte is reported. The gas evolution over the first couple of cycles was thoroughly investigated via differential electrochemical mass spectrometry (DEMS), neutron imaging and pressure measurements. The main oxidation and reduction products were identified as CO2, H2 and C2H4. In different sets of experiments graphite was substituted with delithiated LiFePO4 (LFP) and LNMO with LFP to distinguish between processes occurring at either anode or cathode and gain mechanistic insights. Both C2H4 and H2 were found to be mainly formed at the anode side, while CO2 is generated at the cathode. The results from DEMS analysis further suggest that the Ni redox couples play a profound role in the evolution of CO2 at the LNMO/electrolyte interface. Lastly, it is shown that the cycling stability and capacity retention of LNMO/graphite cells can be considerably improved by a simple cell formation procedure.

8.
Sci Rep ; 5: 15627, 2015 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-26496823

RESUMO

Gas generation as a result of electrolyte decomposition is one of the major issues of high-performance rechargeable batteries. Here, we report the direct observation of gassing in operating lithium-ion batteries using neutron imaging. This technique can be used to obtain qualitative as well as quantitative information by applying a new analysis approach. Special emphasis is placed on high voltage LiNi0.5Mn1.5O4/graphite pouch cells. Continuous gassing due to oxidation and reduction of electrolyte solvents is observed. To separate gas evolution reactions occurring on the anode from those associated with the cathode interface and to gain more insight into the gassing behavior of LiNi0.5Mn1.5O4/graphite cells, neutron experiments were also conducted systematically on other cathode/anode combinations, including LiFePO4/graphite, LiNi0.5Mn1.5O4/Li4Ti5O12 and LiFePO4/Li4Ti5O12. In addition, the data were supported by gas pressure measurements. The results suggest that metal dissolution in the electrolyte and decomposition products resulting from the high potentials adversely affect the gas generation, particularly in the first charge cycle (i.e., during graphite solid-electrolyte interface layer formation).

9.
Ann Agric Environ Med ; Spec no. 1: 39-44, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-25000840

RESUMO

INTRODUCTION: Pain disorders of the spine are the most common causes of appointments with physiotherapists. It has been estimated that nine out of ten adults at least once in their lifetime experience spine pains and five out of ten working people have this kind of ailments a minimum once a year. OBJECTIVE: The evaluation of the occurrence of spine pains in people who are professionally active with regards to obeying the rules of work ergonomics. MATERIAL AND METHODS: The research group has been composed of 100 people professionally active from south-eastern Poland. Their ages have been from 20 to 50 years (average age has been 35 years). In the research the authors' own survey and VAS scale have been used on which the surveyed person has marked the intensity of pain experience in the area of the spine. RESULTS: Greater pain in the spine has been experienced by people who have never obeyed the rules of, among others, manual lifting and/or carrying the maximum load, lifting and carrying heavy objects, in their work. The lowest degree of pain has been experienced by those who obeyed the above-mentioned rules. CONCLUSIONS: Assuming the incorrect body posture during the everyday activities and disobeying the rules of ergonomics resulting from lack of knowledge are crucial factors in the occurrence of spine pains. People who disobey rules of ergonomics experienced spine pain to a higher degree.


Assuntos
Dor nas Costas/epidemiologia , Ergonomia , Doenças Profissionais/epidemiologia , Adulto , Dor nas Costas/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Medição da Dor , Polônia , Trabalho , Adulto Jovem
10.
Bioorg Med Chem ; 12(18): 4895-908, 2004 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-15336269

RESUMO

Synthesis and physicochemical properties of 7-mono- and 6,7-disubstituted dihydrooxazolo-[3,2-f]purinediones are described. Oxazolo[2,3-f]purinediones were synthesized by cyclization of 8-bromotheophylline with oxiranes. The obtained compounds (1-22) were evaluated for their affinity at adenosine A(1) and A(2A) receptors. They showed mainly adenosine A(2A) receptor affinity at low micromolar concentrations and A(2A) selectivity, for example, compound 9 with an octyl substituent at the oxazole ring displayed adenosine A(2A) receptor affinity (K(i)=0.998 microM) and at least 25-fold A(2A) versus A(1) selectivity. This compound was less selective (5-fold) towards human recombinant A(2B) and A(3) adenosine receptors. In this group of compounds active adenosine A(1) receptor antagonists were also identified. Oxazolopurinediones were evaluated in vivo as anticonvulsants in MES and ScMet tests and examined for neurotoxicity in mice (ip). Compounds with long alkyl chains showed anticonvulsant activity in both tests (in 100 and 300 mg/kg doses), accompanied by significant neurotoxicity. The anticonvulsant activity in rats (po) was higher and without signs of neurotoxicity. SAR and QSAR studies stressed the importance of lipophilic 7-substituents for both types of pharmacological activity. The volume of the substituent is, however, limited at the A(2A) AR, an n-octyl group being optimal.


Assuntos
Anticonvulsivantes/metabolismo , Oxazóis/metabolismo , Purinas/metabolismo , Receptores Purinérgicos P1/metabolismo , Animais , Anticonvulsivantes/química , Anticonvulsivantes/uso terapêutico , Humanos , Ligantes , Masculino , Camundongos , Oxazóis/química , Oxazóis/uso terapêutico , Ligação Proteica/fisiologia , Purinas/química , Purinas/uso terapêutico , Ratos , Ratos Sprague-Dawley
11.
Eur J Med Chem ; 39(3): 205-18, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15051168

RESUMO

As a continuation of our search for new ligands acting on benzodiazepine receptors among the fused 2-thiohydantoin derivatives, a series of 5-substituted imidazo[2,1-b]thiazepines was synthesized and investigated in radioligand binding studies at the benzodiazepine binding site of GABA(A) receptors in rat brain cortical membranes. Among ortho-substituted 5-arylidene-imidazo[2,1-b]thiazepines compounds could be identified which exhibit affinity for the benzodiazepine binding site at low micromolar concentrations. X-ray structure analyses for two compounds (6ae and 6ag) have been performed. In order to analyze the structure-activity relationships, 3D models of all compounds have been completed (using X-ray data). Physicochemical properties calculated (log P and log D) as well as experimental thin layer chromatography data were examined.


Assuntos
Anticonvulsivantes/farmacologia , Diazepam/análogos & derivados , Diazepam/síntese química , Receptores de GABA-A/metabolismo , Tiazinas/farmacologia , Animais , Anticonvulsivantes/síntese química , Anticonvulsivantes/química , Sítios de Ligação , Cromatografia em Camada Fina , Diazepam/farmacologia , Antagonistas de Receptores de GABA-A , Ligantes , Masculino , Ratos , Relação Estrutura-Atividade , Tiazinas/síntese química , Tiazinas/química , Difração de Raios X
12.
Eur J Med Chem ; 38(4): 397-402, 2003 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12750027

RESUMO

Adenosine receptor (AR) antagonists belong to two major groups of compounds: xanthines and non-xanthines. Recently several annelated xanthine derivatives have been described as selective A(1), A(2A), A(2B) and A(3) ARs antagonists. Contrary to dipropyl derivatives, in the group of dimethyl (un)substituted arylalkyl pyrimido[2,1-f]purindiones selective mainly adenosine A(2A) receptor antagonists were identified. Their activity depended on aryl substitution and its distance from pyrimido[2,1-f]purindione.


Assuntos
Antagonistas de Receptores Purinérgicos P1 , Purinas/química , Purinas/metabolismo , Pirimidinas/química , Pirimidinas/metabolismo , Antagonistas do Receptor A2 de Adenosina , Animais , Humanos , Estrutura Molecular , Purinas/farmacologia , Pirimidinas/farmacologia , Ratos , Receptor A2A de Adenosina/metabolismo , Receptores Purinérgicos P1/metabolismo , Estereoisomerismo , Relação Estrutura-Atividade , Teofilina/química , Teofilina/metabolismo , Teofilina/farmacologia , Xantinas/química , Xantinas/metabolismo , Xantinas/farmacologia
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