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1.
Int J Mol Sci ; 25(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38791228

RESUMO

Chemotherapeutic drugs are indispensable in cancer treatment, but their effectiveness is often lessened because of non-selective toxicity to healthy tissues, which triggers inflammatory pathways that are harmful to vital organs. In addition, tumors' resistance to drugs causes failures in treatment. Chlorogenic acid (5-caffeoylquinic acid, CGA), found in plants and vegetables, is promising in anticancer mechanisms. In vitro and animal studies have indicated that CGA can overcome resistance to conventional chemotherapeutics and alleviate chemotherapy-induced toxicity by scavenging free radicals effectively. This review is a summary of current information about CGA, including its natural sources, biosynthesis, metabolism, toxicology, role in combatting chemoresistance, and protective effects against chemotherapy-induced toxicity. It also emphasizes the potential of CGA as a pharmacological adjuvant in cancer treatment with drugs such as 5-fluorouracil, cisplatin, oxaliplatin, doxorubicin, regorafenib, and radiotherapy. By analyzing more than 140 papers from PubMed, Google Scholar, and SciFinder, we hope to find the therapeutic potential of CGA in improving cancer therapy.


Assuntos
Ácido Clorogênico , Resistencia a Medicamentos Antineoplásicos , Neoplasias , Humanos , Ácido Clorogênico/farmacologia , Ácido Clorogênico/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Animais , Antineoplásicos/uso terapêutico , Antineoplásicos/farmacologia
2.
Antioxidants (Basel) ; 12(8)2023 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-37627495

RESUMO

Neurodegenerative disorders are characterized by a progressive process of degeneration and neuronal death, where oxidative stress and neuroinflammation are key factors that contribute to the progression of these diseases. Therefore, two major pathways involved in these pathologies have been proposed as relevant therapeutic targets: The nuclear transcription factor erythroid 2 (Nrf2), which responds to oxidative stress with cytoprotecting activity; and the nuclear factor NF-κB pathway, which is highly related to the neuroinflammatory process by promoting cytokine expression. Caffeic acid phenethyl ester (CAPE) is a phenylpropanoid naturally found in propolis that shows important biological activities, including neuroprotective activity by modulating the Nrf2 and NF-κB pathways, promoting antioxidant enzyme expression and inhibition of proinflammatory cytokine expression. Its simple chemical structure has inspired the synthesis of many derivatives, with aliphatic and/or aromatic moieties, some of which have improved the biological properties. Moreover, new drug delivery systems increase the bioavailability of these compounds in vivo, allowing its transcytosis through the blood-brain barrier, thus protecting brain cells from the increased inflammatory status associated to neurodegenerative and psychiatric disorders. This review summarizes the biosynthesis and chemical synthesis of CAPE derivatives, their miscellaneous activities, and relevant studies (from 2010 to 2023), addressing their neuroprotective activity in vitro and in vivo.

3.
Nat Prod Res ; 37(14): 2466-2471, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35707900

RESUMO

Furofuran lignanes show important biological activities for the treatment of infectious diseases, inflammatory and metabolic pathologies. They have been isolated from leaves and barks of many plants. In Chile the native conifer Araucaria araucana produces eudesmin, matairesinol, secoisolariciresinol and lariciresinol in stemwood, branchwood and knotwood. These compounds were previously isolated by laborious flash chromatography on silica gel. Here we report the easy isolation of eudesmin by soxhlet extraction from milled knots of Araucaria araucana with hexane, followed by cryo-crystallization at -20 °C. Upon bromination of the isolated eudesmin epimerization at one benzylic position occurs, giving epieudesmin and the corresponding mono and di-brominated derivatives. The structures were determined by 1D, 2D NMR and X-ray diffraction. The analysis of products against Candida yeast showed that eudesmin has a moderate activity against different strains of Candida from 62.5 to 500 µg/mL. This activity decreases for epieudesmin, while bromine derivatives are not active.


Assuntos
Araucaria araucana , Bromo , Candida , Halogenação
4.
Nat Prod Res ; 36(24): 6318-6323, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35021940

RESUMO

Drimys winteri J.R.Forst. & G.Forst, a South American evergreen shrub that is used by the Mapuche people for treatment of several painful conditions, contains polygodial, a lipophilic drimane-type sesquiterpene dialdehyde with known activity at transient receptor potential channel family members including TRPA1 and TRPV1. We sought to assess the activity of polygodial at NaV1.7 and NaV1.8, two key isoforms of the voltage-gated sodium channel family involved in nociception. Polygodial was isolated from D. winteri by thin-layer chromatography and analysed structurally by 1 D and 2 D nuclear magnetic resonance (NMR) spectroscopy. Activity at heterologously expressed NaV1.7 and NaV1.8 was assessed using automated whole-cell patch-clamp electrophysiology. Here, we show that polygodial inhibits members of the voltage-gated sodium channel family, specifically NaV1.7 and NaV1.8, without changing the voltage-dependence of activation or inactivation. Activity of polygodial at voltage-gated sodium channels may contribute to the previously reported antinociceptive properties.


Assuntos
Drimys , Sesquiterpenos , Canais de Sódio Disparados por Voltagem , Humanos , Sesquiterpenos/farmacologia
5.
J Environ Manage ; 273: 111154, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32771852

RESUMO

The frequent environment-unfriendly treatments of agro-industrial bio-wastes cause severe pollution through air pollution and through residual effluents and hazardous solid waste. These bio-wastes can contain phenolic compounds, forms of phenolic acids and flavonoids in plants. They are however the most abundant class of many phytochemicals and have been given great interest due to their health advantage and high economic value. An interesting upgrading of these bio-wastes may consist in obtaining a concentrated extract of phenolic compounds using no-toxic solvents, hence protecting the environment and human health. In this work, different alternatives of the extraction process were evaluated using an exergetic analysis. The energy and water consumptions, CO2 emissions, exergetic yield, wasted and destroyed exergy were calculated. It was found that several alternatives for recycle streams were convenient (streams with higher chemical exergy were not discharged into the environment). The energy and water consumption for the best alternative (ethanol-water ratio 1/1 including recycle stream, named E-W 1/1 Rec) were 567 MJ/h and 105 kg/h, respectively and the CO2 emission was 105 kg/h. The calculated exergy destruction indicated that the evaporation and distillation stages may be optimized towards a more sustainable operation. It is not advisable to dry the bio-waste if it will be immediately processed once generated.


Assuntos
Poluição do Ar , Resíduos Industriais , Flavonoides , Humanos , Fenóis , Reciclagem
6.
Biomolecules ; 10(8)2020 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-32722158

RESUMO

Candida species cause an opportunistic yeast infection called Candidiasis, which is responsible for more than 50,000 deaths every year around the world. Effective treatments against candidiasis caused by non-albicans Candida species such as C. glabrata, C. parapsilosis, C. aureus, and C.krusei are limited due to severe resistance to conventional antifungal drugs. Natural drimane sesquiterpenoids have shown promising antifungal properties against Candida yeast and have emerged as valuable candidates for developing new candidiasis therapies. In this work, we isolated isodrimeninol (C1) from barks of Drimys winteri and used it as starting material for the hemi-synthesis of four sesquiterpenoids by oxidation with pyridinium chlorochromate (PCC). The structure of the products (C2, C3, C4, and C5) was elucidated by 1D and 2D NMR spectroscopy resulting in C4 being a novel compound. Antifungal activity assays against C. albicans, C. glabrata, and C. krusei revealed that C4 exhibited an increased activity (IC50 of 75 µg/mL) compared to C1 (IC50 of 125 µg/mL) in all yeast strains. The antifungal activity of C1 and C4 was rationalized in terms of their capability to inhibit lanosterol 14-alpha demethylase using molecular docking, molecular dynamics simulations, and MM/GBSA binding free energy calculations. In silico analysis revealed that C1 and C4 bind to the outermost region of the catalytic site of 14-alpha demethylase and block the entrance of lanosterol (LAN) to the catalytic pocket. Binding free energy estimates suggested that C4 forms a more stable complex with the enzyme than C1, in agreement with the experimental evidence. Based on this new approach it is possible to design new drimane-type sesquiterpenoids for the control of Candida species as inhibitors of 14-alpha demethylase.


Assuntos
Inibidores de 14-alfa Desmetilase/química , Candida/crescimento & desenvolvimento , Sesquiterpenos Policíclicos/química , Compostos de Piridínio/química , Sesquiterpenos/química , Esterol 14-Desmetilase/química , Inibidores de 14-alfa Desmetilase/síntese química , Inibidores de 14-alfa Desmetilase/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Domínio Catalítico , Humanos , Espectroscopia de Ressonância Magnética , Simulação de Acoplamento Molecular , Estrutura Molecular , Oxirredução , Sesquiterpenos Policíclicos/síntese química , Sesquiterpenos Policíclicos/farmacologia , Domínios Proteicos , Compostos de Piridínio/metabolismo , Sesquiterpenos/síntese química , Sesquiterpenos/farmacologia , Esterol 14-Desmetilase/metabolismo
7.
Food Chem Toxicol ; 109(Pt 2): 984-995, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28501487

RESUMO

It is reported in this study the effect of isolates from leaves of Aristotelia chilensis as inhibitors of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and tyrosinase enzymes. The aim of the paper was to evaluate the activity of A. chilensis towards different enzymes. In addition to pure compounds, extracts rich in alkaloids and phenolics were tested. The most active F5 inhibited AChE (79.5% and 89.8% at 10.0 and 20.0 µg/mL) and against BChE (89.5% and 97.8% at 10.0 and 20.0 µg/mL), showing a strong mixed-type inhibition against AChE and BChE. F3 (a mixture of flavonoids and phenolics acids), showed IC50 of 90.7 and 59.6 µg/mL of inhibitory activity against AChE and BChE, inhibiting the acetylcholinesterase competitively. Additionally, F3 showed and high potency as tyrosinase inhibitor with IC50 at 8.4 µg/mL. Sample F4 (anthocyanidins and phenolic composition) presented a complex, mixed-type inhibition of tyrosinase with a IC50 of 39.8 µg/mL. The findings in this investigation show that this natural resource has a strong potential for future research in the search of new phytotherapeutic treatments for cholinergic deterioration ailments avoiding the side effects of synthetic drugs. This is the first report as cholinesterases and tyrosinase inhibitors of alkaloids and phenolics from A. chilensis leaves.


Assuntos
Alcaloides/química , Inibidores da Colinesterase/química , Magnoliopsida/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Fenóis/química , Extratos Vegetais/química , Alcaloides/isolamento & purificação , Antioxidantes/química , Antioxidantes/isolamento & purificação , Inibidores da Colinesterase/isolamento & purificação , Colinesterases/química , Colinesterases/metabolismo , Flavonoides/química , Flavonoides/isolamento & purificação , Cinética , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/metabolismo , Fenóis/isolamento & purificação , Extratos Vegetais/isolamento & purificação , Folhas de Planta/química
8.
Acta Crystallogr E Crystallogr Commun ; 73(Pt 3): 334-337, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28316802

RESUMO

The title compound, erioflorin, C19H24O6 [systematic name: (1aR,3S,4Z,5aR,8aR,9R,10aR)-1a,2,3,5a,7,8,8a,9,10,10a-deca-hydro-3-hy-droxy-4,10a-dimethyl-8-methyl-idene-7-oxooxireno[5,6]cyclo-deca-[1,2-b]furan-9-yl methacrylate], is a tricyclic germacrane sesquiterpene lactone, which was isolated from Podanthus mitiqui (L.). The compound crystallizes in the space group P212121, and its mol-ecular structure consists of a methacrylic ester of a ten-membered ring sesquiterpenoid annelated with an epoxide and a butyrolactone. The structure is stabilized by one intramolecular C-H⋯O hydrogen bond. An O-H⋯O hydrogen bond and further C-H⋯O interactions can be observed in the packing.

9.
Acta Crystallogr C ; 62(Pt 2): o76-8, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16456291

RESUMO

The title compound, C14H25N3O2, consists of a five-membered heterocyclic ring to which a pendant decyl group is attached. The oximino tautomeric character of the molecule is clearly defined by the distribution of well defined double bonds in the heterocycle region (one C=O and two C=N). The most conspicuous packing interaction is the strong intermolecular hydrogen bond linking the oximino OH group and the carbonyl O atom to define broad planar hydrophilic strips running along the unique b axis. The alkyl chains adopt a fully extended conformation and lie almost at right angles to these one-dimensional structures, defining their hydrophobic counterpart.

12.
Trinidad; s.n; 1999. [27] p.
Não convencional em Espanhol | LIBOCS, LIBOSP | ID: biblio-1301055

RESUMO

El siguiente trabajo fue realizado mediante encuestas sobre educación sanitaria, con el objetivo de realizar el proyecto de resolución ministerial de aprobación de reglamentos y manuales para el programa de control y erradicación de la fiebre aftosa, control de remates ferias y exposiciones, reglamento para la importación de vacunas, sobre estructura física de remates y ferias, medidas sanitarias para la primera fase del proyecto, para la atención de focos de fiebre aftosa y transporte de ganado


Assuntos
Agricultura , Animais Domésticos , Consultores , Febre Aftosa , Bolívia , Relatório Anual , Legislação/normas , Manual de Referência , Vigilância Sanitária
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