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1.
Food Chem Toxicol ; 131: 110535, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31154083

RESUMO

This study endeavours to investigate the phytochemical composition, biological properties and in vivo toxicity of methanol and dichloromethane extracts of Zaleya pentandra (L.) Jeffrey. Total bioactive contents, antioxidant (phosphomolybdenum and metal chelating, DPPH, ABTS, FRAP and CUPRAC) and enzyme inhibition (cholinesterases, tyrosinase α-amylase, and α-glucosidase) potential were assessed utilizing in vitro bioassays. UHPLC-MS phytochemical profiling was carried out to identify the essential compounds. The methanol extract was found to contain highest phenolic (22.60 mg GAE/g) and flavonoid (31.49 mg QE/g) contents which correlate with its most significant radical scavenging, reducing potential and tyrosinase inhibition. The dichloromethane extract was most potent for phosphomolybdenum, ferrous chelation, α-amylase, α-glucosidase, and cholinesterase inhibition assays. UHPLC-MS analysis of methanol extract unveiled to identify 11 secondary metabolites belonging to five sub-groups, i.e., phenolic, alkaloid, carbohydrate, terpenoid, and fatty acid derivatives. Additionally, in vivo toxicity was conducted for 21 days and the methanol extract at different doses (150, 200, 250 and 300 mg/kg) was administered in experimental chicks divided into five groups each containing five individuals. Different physical, haematological and biochemical parameters along with the absolute and relative weight of visceral body organs were studied. Overall, no toxic effect was noted for the extract at tested doses.


Assuntos
Aizoaceae/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Administração Oral , Animais , Galinhas , Inibidores Enzimáticos/administração & dosagem , Inibidores Enzimáticos/química , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/toxicidade , Depuradores de Radicais Livres/administração & dosagem , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Metanol/química , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química
2.
Food Chem Toxicol ; 131: 110539, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31158404

RESUMO

The chemical characterization and protective role against ethanol-induced gastric ulcerated rats of a polysaccharide fraction from Bletilla striata (BSP) collected by ultrafiltration membrane approach were evaluated. This BSP faction was consisted of mannose and glucose at a molar ratio of 2.4:1 approximately, with a molecular weight of 146 KDa. FT-IR, NMR and XRD spectra indicated that BSP faction contained α-Man and ß-Glc residues with low overall crystallinity. The polysaccharide exhibited significant scavenging activities of ABTS and FRAP, as well as non-toxicity against human gastric epithelial GES-1 cells. Oral administration with 100 mg/kg of BSP for 3 days continuously could significantly prevent the formation of ethanol-induced gastric mucosal lesion. It could also reduce the levels of pro-inflammatory cytokines, including TNF-α, IL-1ß, IL-6, and IL-18, and MPO activity in gastric tissue. Additionally, the BSP faction exhibited antioxidant activity, increased the content of PEG2 as a defensive factor, and suppressed MAPK/NF-κB signaling pathway in gastric tissue. These results indicated that the gastroprotective activity of BSP faction could be attributed to the reduction of pro-inflammatory cytokines and oxidative stress and the inhibition of MAPK/NF-κB pathways. Our results provided substantial evidence that BSP could be a promising phytomedicine for gastric ulcer prevention.


Assuntos
Fármacos Gastrointestinais/farmacologia , Orchidaceae/química , Polissacarídeos/farmacologia , Úlcera Gástrica/tratamento farmacológico , Animais , Anti-Inflamatórios/isolamento & purificação , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/toxicidade , Linhagem Celular , Citocinas/metabolismo , Dinoprostona/metabolismo , Etanol , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Mucosa Gástrica/patologia , Fármacos Gastrointestinais/isolamento & purificação , Fármacos Gastrointestinais/toxicidade , Humanos , Estresse Oxidativo/efeitos dos fármacos , Peroxidase/metabolismo , Polissacarídeos/isolamento & purificação , Polissacarídeos/toxicidade , Ratos , Transdução de Sinais/efeitos dos fármacos , Úlcera Gástrica/induzido quimicamente , Superóxido Dismutase/metabolismo
3.
Eur J Med Chem ; 174: 216-225, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31042617

RESUMO

The identification of a valid therapeutic treatment for Alzheimer's disease (AD) represents nowadays an urgent and still unmet medical need, since currently available anti-AD drugs only relieve symptoms and show a modest efficacy. Recent evidence indicates that multi-target-directed ligands (MTDLs) can potentially provide an effective strategy to develop innovative therapies directed towards the onset and progression of this multifactorial neurodegenerative disorder. In this work we designed, synthesized and evaluated a new series of MTDLs bearing the rivastigmine skeleton (ChE-inhibitor) linked to known metal-chelating moieties with linkers of different length. For all the novel derivatives, AChE/BuChE inhibitory activity, ROS scavenging activity and potential cytotoxicity have been assessed. For the best compound (4), copper chelating properties and neuroprotective effects were also evaluated. Our data demonstrated that hybrid derivative 4 is able to effectively inhibit AChE and BuChE and to chelate copper, showing a protective action on neurons. These results, although preliminary, indicate that compound 4 can be considered as a possible hit molecule for the development of new anti-AD MTDLs.


Assuntos
Quelantes/farmacologia , Complexos de Coordenação/farmacologia , Cobre/química , Fármacos Neuroprotetores/farmacologia , Rivastigmina/análogos & derivados , Rivastigmina/farmacologia , Acetilcolinesterase/metabolismo , Animais , Butirilcolinesterase/metabolismo , Linhagem Celular Transformada , Quelantes/síntese química , Quelantes/toxicidade , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/farmacologia , Inibidores da Colinesterase/toxicidade , Complexos de Coordenação/síntese química , Complexos de Coordenação/toxicidade , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Camundongos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/toxicidade , Rivastigmina/síntese química , Rivastigmina/toxicidade
4.
Carbohydr Polym ; 216: 270-281, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31047067

RESUMO

The fine structure and chain conformation of a heteropolysaccharide (PCIPS3) from mycelium of Paecilomyces cicadae were investigated via the analysis of HPLC, IR, methylation, NMR spectroscopy and multiangle light scattering. It was determined to be a 2.23 × 104 g/mol heteropolysaccharide primarily composed of glucose, galactose and mannose in a molar ratio of 23.8:2.1:1.0. The PCIPS3 backbone consisted of 1,4-linked α-d-Glcp and 1,4-linked 6-O-Me-α-d-Glcp residues, which were occasionally interrupted by branched ß-Galf residues through 1,6-linkage. Moreover, the α (0.60) from Mark-Houwink-Sakurada (MHS) equation suggested that PCIPS3 adopted a flexible chain conformation in 0.1 mol/L NaNO3 at 25 °C. The worm-like chains model parameters for PCIPS3 were estimated as following: ML = 437 nm-1, q = 0.46 nm and 0.79 nm, which were further evidenced by AFM. Furthermore, PCIPS3 showed excellent scavenging capacities of 2,2-diphenyl-1-picrylhydrazyl radical, superoxide radical, hydroxyl radical, ORAC radical and moderate immunomodulatory activity.


Assuntos
Depuradores de Radicais Livres/farmacologia , Polissacarídeos Fúngicos/farmacologia , Fatores Imunológicos/farmacologia , Paecilomyces/química , Animais , Configuração de Carboidratos , Sobrevivência Celular/efeitos dos fármacos , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/toxicidade , Polissacarídeos Fúngicos/química , Polissacarídeos Fúngicos/isolamento & purificação , Polissacarídeos Fúngicos/toxicidade , Radical Hidroxila/química , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Fatores Imunológicos/toxicidade , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Camundongos , Peróxidos/química , Células RAW 264.7 , Superóxidos/química , Fator de Necrose Tumoral alfa/metabolismo
5.
Int J Biol Macromol ; 128: 391-400, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-30684583

RESUMO

Lignin, is the most abundant, renewable and degradable biopolymer available in the nature. The present study exploited purified lignin from wheat straw as reducing, capping and stabilizing agent for the green synthesis of silver nanoparticles (Li-AgNPs) under optimized conditions. The analytical studies revealed synthesized Li-AgNPs having a face centered cubic crystalline structure, size ranging ~15-20 nm and the biomolecules comprising majorly phenolic, hydroxyl and carboxylic group of lignin coated on the surface of AgNPs. Li-AgNPs showed significant antimicrobial efficacy against human pathogens namely; Staphylococcus aureus and Escherichia coli and also determined their minimum inhibitory and minimum bactericidal concentration (MIC and MBC). Li-AgNPs also displayed substantial antioxidant activity in terms of well-known enzyme marker viz.; ABTS and DPPH free radical scavenging assay relative to commercial AgNPs. In vitro cytotoxicity assay of Li-AgNPs demonstrated dose-dependent toxicity effects in SKOV3 ovarian cancer cell line (LD50; 150 µg/mL) indicative of promising anticancer agent. Further, H2O2 sensing ability of stabilized Li-AgNPs exhibited its vital role in determining reactive oxygen species. Synthesis of Li-AgNPs is a cheap green technology and could exhibit its commercial use in biomedical, cosmetic, and pharmaceutical industry.


Assuntos
Peróxido de Hidrogênio/análise , Lignina/química , Nanopartículas Metálicas , Prata/química , Prata/farmacologia , Triticum/química , Antibacterianos/síntese química , Antibacterianos/química , Antibacterianos/farmacologia , Antibacterianos/toxicidade , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/toxicidade , Benzotiazóis/química , Compostos de Bifenilo/química , Linhagem Celular Tumoral , Escherichia coli/efeitos dos fármacos , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Química Verde , Humanos , Picratos/química , Prata/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Ácidos Sulfônicos/química
6.
Bioorg Med Chem ; 27(2): 410-415, 2019 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-30554969

RESUMO

The use of antioxidants is the most effective means to protect the organism against cellular damage caused by oxidative stress. In this context, organotellurides have been described as promising antioxidant agents for decades. Herein, a series of N-functionalized organotellurium compounds has been tested as antioxidant and presented remarkable activities by three different in vitro chemical assays. They were able to reduce DPPH radical with IC50 values ranging from 5.08 to 19.20 µg mL-1, and some of them also reduced ABTS+ radical and TPTZ-Fe3+ complex in ABTS+ and FRAP assays, respectively. Initial structure-activity relationship discloses that the nature of N-substituent strongly influenced both activity and cytotoxicity of the studied compounds. Furthermore, radical scavenging activities of N-functionalized organotellurides have been compared with those of their selenilated congeners, demonstrating that the presence of tellurium atom has an essential role in antioxidant activity.


Assuntos
Depuradores de Radicais Livres/química , Compostos Organometálicos/química , Telúrio/química , Animais , Benzotiazóis/química , Compostos de Bifenilo/química , Desenho de Drogas , Fibroblastos/efeitos dos fármacos , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/toxicidade , Camundongos , Estrutura Molecular , Compostos Organometálicos/síntese química , Compostos Organometálicos/toxicidade , Oxirredução , Picratos/química , Relação Estrutura-Atividade , Ácidos Sulfônicos/química
7.
Carbohydr Polym ; 205: 63-71, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30446149

RESUMO

A novel water-soluble polysaccharide designated as TPS was isolated from the fermentation mycelia of Trichoderma kanganensis. TPS had a weight-average molecular mass of 3.074 × 105 Da, and the monosaccharide composition was consisted of Man (45.5%), GlcA (5.5%), Glc (10%), and Gal (39%). The major backbone of TPS was →6-α-d-Galp-1→5-ß-d-Manf-1→5,6-ß-d-Manf-1→5,6-ß-d-Manf-1→, and the side chains are α-d-Glcp-1→4-α-d-Glcp-1→, ß-d-Galf-1→, and α-d-Glcp-1→. In addition, we demonstrated that TPS was non-toxic in normal cells (LO2 cells) and inhibited the proliferation of mouse colon cells (CT26 cells). TPS also showed free radical scavenging activity against hydrogen peroxide. Overall, these results suggested that TPS from Trichoderma kanganensis may have potential application in biomedical fields.


Assuntos
Antineoplásicos/farmacologia , Depuradores de Radicais Livres/farmacologia , Polissacarídeos/farmacologia , Trichoderma/química , Animais , Antineoplásicos/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/toxicidade , Apoptose/efeitos dos fármacos , Sequência de Carboidratos , Linhagem Celular Tumoral , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/toxicidade , Hepatócitos/efeitos dos fármacos , Humanos , Camundongos , Peso Molecular , Micélio/química , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Polissacarídeos/toxicidade
8.
Carbohydr Polym ; 206: 468-475, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30553346

RESUMO

Free radicals are closely related to the occurrence and development of aging, cancer and inflammation. In this paper, the microbial transglutaminase (MTGase) was used as a catalyst to graft the collagen peptide (COP) molecules on the amino group of carboxymethyl chitosan sulfate (CMCS) to improve the antioxidant effects. FT-IR and NMR spectroscopy were used to confirm the successful grafting of COP to CMCS. Degree of substitution (DS) of CMCS-COP could be controlled by adjusting the reaction conditions. With the increase of concentration, the ability of each sample on scavenging capacity and reducibility tends to increase obviously. The results of anticoagulant experiments showed that the ability of CMCS and CMCS-COP with three different degrees of substitution on activated partial thrombin time (APTT) and prothrombin time (PT) values were all increased to compare with the control group. No relevant cytotoxicity against NIH-3T3 mouse fibroblasts was found for the copolymers. These results suggested that CMCS-COP would appear to be a promising candidate for wound dressing application.


Assuntos
Quitosana/análogos & derivados , Colágeno/farmacologia , Fragmentos de Peptídeos/farmacologia , Transglutaminases/química , Animais , Anticoagulantes/síntese química , Anticoagulantes/química , Anticoagulantes/farmacologia , Anticoagulantes/toxicidade , Bandagens , Quitosana/síntese química , Quitosana/química , Quitosana/farmacologia , Quitosana/toxicidade , Colágeno/síntese química , Colágeno/química , Colágeno/toxicidade , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Camundongos , Estrutura Molecular , Células NIH 3T3 , Oxirredução , Tempo de Tromboplastina Parcial , Fragmentos de Peptídeos/síntese química , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/toxicidade , Tempo de Protrombina , Temperatura Ambiente
9.
Carbohydr Polym ; 206: 493-503, 2019 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-30553350

RESUMO

In this paper, a series of 6-O-imidazole-based quaternary ammonium chitosan derivatives via 6-O-chloroacetyl chitosan (CAClC) were successfully designed and synthesized. Detailed structural characterization was carried out by means of FT-IR and 1H NMR spectroscopy, and elemental analysis. Furthermore, the antioxidant property against hydroxyl radicals, superoxide radicals, and DPPH radicals was evaluated in vitro. 2-(N,N,N-trimethyl)-6-O-(2-aminobenzimidazole)acetyl chitosan chloride (2NPhMC) and 2-(N,N,N-trimethyl)-6-O-(1-butylimidazole)acetyl chitosan chloride (NBMC) showed more than 90% scavenging indices at 1.6 mg/mL. Besides, the antifungal activity against Botrytis cinerea and Gibberella zeae was estimated using in vitro MIC and hypha measurements. Most of the quaternized chitosan derivatives especially with the long length alkyl chain and primary amino group showed an inhibitory index of > 85% at 1.0 mg/mL against Botrytis cinerea. Besides, the cytotoxicity of chitosan and all the quaternized chitosan derivatives was evaluated in vitro on HaCaT cells and all the quaternized chitosan derivatives bearing 6-O-imidazole exhibited low cytotoxicity. These results suggested that chitosan derivatives bearing 6-O-imidazole-based quaternary ammonium salts may be used as good biomaterials.


Assuntos
Antifúngicos/farmacologia , Quitosana/análogos & derivados , Quitosana/farmacologia , Depuradores de Radicais Livres/farmacologia , Imidazóis/farmacologia , Compostos de Amônio Quaternário/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Antifúngicos/toxicidade , Botrytis/efeitos dos fármacos , Quitosana/síntese química , Quitosana/toxicidade , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/toxicidade , Gibberella/efeitos dos fármacos , Células HeLa , Humanos , Imidazóis/síntese química , Imidazóis/química , Imidazóis/toxicidade , Testes de Sensibilidade Microbiana , Micélio/efeitos dos fármacos , Compostos de Amônio Quaternário/síntese química , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/toxicidade , Solubilidade
10.
Neuro Endocrinol Lett ; 39(4): 294-298, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30531698

RESUMO

OBJECTIVES: Bisphenol A (BPA) is an endocrine disruptor which has been shown to be a harmful compound for living organisms. It is the main component of the most commonly used plastic products such as plastic bottles, food cans and containers or dental fillings, and other medical aids. Recently, it has become a new environmental pollutant. The current knowledge about the BPA effects (including genotoxic one) on different cells is in many cases contradictory. Thus, the aim of the paper is to study the potential genotoxic effect of BPA. METHODS: An observation of the genotoxic activity of BPA on human lymphocytes was evaluated by using the alkaline comet assay and a modified comet assay with bacterial DNA repair enzyme Fpg. The potential DNA-protective effect of BPA was tested by using the DNA-topology assay. RESULTS: The results show that rising concentrations of BPA increase the risk of DNA double-strand breaks and modified purines in human lymphocytes. Interestingly, BPA shows an ability to protect plasmid DNA from the damage of iron ions in cell-free system. CONCLUSIONS: BPA itself does not induce genotoxic effect to DNA. However, BPA treatment of human lymphocytes leads to the induction of DNA damage. The proposed mechanism of BPA action in the human lymphocytes could be mediated by cell metabolism that induces an oxidative stress and ROS formation. ROS subsequently attack DNA and thus induce DNA damage. According to our results, BPA can be included in the group of substances with dual effects involving genotoxic and DNA-protective activity.


Assuntos
Compostos Benzidrílicos/toxicidade , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , DNA/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Linfócitos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/toxicidade , Plasmídeos/efeitos dos fármacos , Ensaio Cometa , DNA/genética , Dano ao DNA/genética , Disruptores Endócrinos/toxicidade , Estrogênios não Esteroides/toxicidade , Depuradores de Radicais Livres/toxicidade , Humanos , Linfócitos/metabolismo , Plasmídeos/genética , Purinas/metabolismo , Espécies Reativas de Oxigênio/metabolismo
11.
Chemosphere ; 209: 508-516, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29940534

RESUMO

Bisphenol A (BPA) is used as the main component of many consumer products such as infant's feeding bottles, coatings of beverages, and food cans. BPA can migrate into the environment, and it has been detected in the saliva, blood, and food. BPA leakage from many consumer products resulted in a ban on its use in many countries where alternatives to BPA were introduced into the market. BPA alternatives such as bisphenol B (BPB), bisphenol F (BPF), and bisphenol S (BPS) have a similar chemical structure and binding ability for estrogen receptor (ER), which shows toxicological effects in animals. In the present study, comparative effects of exposure to BPA and its analogs BPB, BPF, and BPS on testosterone concentration in the rat testis were evaluated by in vitro and in vivo approaches in which oxidative stress markers and antioxidant enzyme activities in reproductive tissues were determined. In the in vivo study, male rats were exposed to different concentrations of BPA and its analogs BPB, BPF, and BPS (5, 25, and 50 mg/kg/day) for 28 days. In the in vitro exposure study, antioxidant enzyme activities and oxidative stress markers were induced in the testes, whereas testosterone production was reduced. In the in vivo exposure study, we observed that antioxidant enzyme activities and protein content were reduced, whereas reactive oxygen species and lipid profile were increased in the treated groups compared to the control group. The present comparative study on BPA and its analogs, namely, BPB, BPF, and BPS suggests the toxic effect of these chemicals on the testes and spermatogenesis, and we also observed that these chemicals induce oxidative stress in the reproductive tissues of male rats.


Assuntos
Compostos Benzidrílicos/toxicidade , Depuradores de Radicais Livres/toxicidade , Fenóis/toxicidade , Espermatozoides/patologia , Sulfonas/toxicidade , Testículo/patologia , Animais , Técnicas In Vitro , Masculino , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Receptores Estrogênicos/metabolismo , Espermatozoides/efeitos dos fármacos , Espermatozoides/metabolismo , Testículo/efeitos dos fármacos , Testículo/metabolismo , Testosterona/metabolismo
12.
Oxid Med Cell Longev ; 2018: 3246719, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29854079

RESUMO

The seed oil of Carapa guianensis (Aublet), a tree from the Meliaceae family commonly known as andiroba, is widely used in Brazilian traditional medicine because of its multiple curative properties against fever and rheumatism and as an anti-inflammatory agent, antibacterial agent, and insect repellant. Since there is no consensus on the best way to obtain the C. guianensis oil and due to its ethnomedicinal properties, the aim of the present research was to evaluate the chemical composition, free-radical scavenging activity, and mutagenic and genotoxicity properties of three C. guianensis oils obtained by different extraction methods. The phenolic contents were evaluated by spectrophotometry. Oil 1 was obtained by pressing the dried seeds at room temperature; oil 2 was obtained by autoclaving, drying, and pressing; oil 3 was obtained by Soxhlet extraction at 30-60°C using petroleum ether. The oil from each process presented differential yields, physicochemical properties, and phenolic contents. Oil 1 showed a higher scavenging activity against the DPPH radical when compared to oils 2 and 3, suggesting a significant antioxidant activity. All oils were shown to be cytotoxic to bacteria and to CHO-K1 and RAW264.7 cells. At noncytotoxic concentrations, oil 2 presented mutagenicity to Salmonella enterica serovar Typhimurium and induced micronuclei in both cell types. Under the same conditions, oil 3 also induced micronucleus formation. However, the present data demonstrated that oil 1, extracted without using high temperatures, was the safest for use as compared to the other two oils, not showing mutagenicity or micronucleus induction.


Assuntos
Meliaceae/química , Óleos Vegetais/química , Óleos Vegetais/toxicidade , Animais , Antioxidantes/química , Antioxidantes/toxicidade , Células CHO , Cricetulus , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/toxicidade , Camundongos , Testes para Micronúcleos , Testes de Mutagenicidade , Fenóis/análise , Fenóis/toxicidade , Células RAW 264.7 , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Sementes/química
13.
Carbohydr Polym ; 190: 175-183, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29628235

RESUMO

Chondroitin sulfate (CS) was regio-specifically modified to an unsaturated derivative (ΔCS) with a double bond in positions 4 and 5 of N-acetyl-d-galactosamine. The structure of ΔCS was elucidated in detail by two dimensional nuclear magnetic resonance, ultraviolet spectroscopy and mass spectrometry. The introduction of a nucleophilic CC double bond into a polymer backbone had no influence on biocompatibility of CS, which was demonstrated by MTT live-dead assay and enzymatic degradation in vitro. On the other hand the chemical modification significantly enhanced the reactivity of ΔCS towards numerous oxidizing agents, which might be promising for a variety of biomedical and cosmetic applications.


Assuntos
Sulfatos de Condroitina/química , Sulfatos de Condroitina/síntese química , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/síntese química , Células 3T3 , Animais , Compostos de Bifenilo/química , Técnicas de Química Sintética , Sulfatos de Condroitina/toxicidade , Depuradores de Radicais Livres/toxicidade , Teste de Materiais , Camundongos , Oxirredução , Picratos/química
14.
J Basic Clin Physiol Pharmacol ; 29(3): 291-299, 2018 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-29303776

RESUMO

BACKGROUND: The present study was planned to investigate the phytochemical, antioxidant, antinociceptive, anticoagulant and cytotoxic activities of the Jacquemontia tamnifolia (L.) Griseb leaf methanol extract (MExJT) in the laboratory using both in vitro and in vivo methods. METHODS: Phytochemical values, namely, total phenolic and flavonoid contents, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging effect and FeCl3 reducing power effects, were studied by established methods. In vivo antinociceptive activity was performed by acidic acid-induced writhing test and formalin-induced pain test on Swiss albino mice at doses of 125, 250 and 500 mg/kg body weight. The clot lysis and brine shrimp lethality bioassay in vitro were used to evaluate the thrombolytic and cytotoxic activities of the plant extract, respectively. RESULTS: Phytochemical screening illustrates the presence of tannins, saponins, flavonoids, gums and carbohydrates, steroids, alkaloids and reducing sugars in the extract. The results showed the total phenolic content (146.33 g gallic acid equivalents/100 g extract) and total flavonoid content (133.33 g quercetin/100 g). Significant (p<0.05) IC50 values compared to respective standards were recorded in DPPH radical scavenging (289.5 µg/mL) and FeCl3 reduction (245.2 µg/mL). The antinociceptive effect was evaluated in the acetic acid-induced writhing test and formalin-induced pain models in Swiss albino mice with doses of 125, 250 and 500 mg/kg body weight. Significant (p<0.05) inhibition (72.87±2.73%) of writhing response compared to diclofenac sodium was achieved by 500 mg/kg body weight. The extract also significantly inhibited the licking response in both the early phase (51.59±1.57%, p<0.05) and the late phase (64.82±1.87%, p<0.05) in the formalin-induced writhing test. MExJT also showed (38.10±1.79%) clot lytic activity in the thrombolytic test and cytotoxicity with an LC50 value of 31.70 µg/mL in the brine shrimp lethality bioassay. CONCLUSIONS: The plant is a potential source of antioxidants and might have one or more secondary metabolite(s) with central and peripheral analgesic activity. The results also demonstrate that MExJT has moderate thrombolytic and lower cytotoxic properties that may warrant further exploration.


Assuntos
Anticoagulantes/farmacologia , Antioxidantes/farmacologia , Convolvulaceae/química , Extratos Vegetais/farmacologia , Analgésicos/isolamento & purificação , Analgésicos/farmacologia , Analgésicos/toxicidade , Animais , Anticoagulantes/isolamento & purificação , Anticoagulantes/toxicidade , Antioxidantes/isolamento & purificação , Antioxidantes/toxicidade , Artemia/efeitos dos fármacos , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Concentração Inibidora 50 , Dose Letal Mediana , Masculino , Camundongos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/toxicidade , Folhas de Planta
15.
J Oleo Sci ; 66(11): 1263-1271, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29021490

RESUMO

A new amphiphilic antioxidant (tannyl stearate) derived from reaction of tannic acid with stearic acid was synthesized in order to improve tannic acid solubility in lipid materials. This reaction gives many products having different degree of esterification (tannyl mono, di, tri, tetra, penta, hexa, hepta……stearate) which were separated using silica gel column chromatography and tentative identification was carried out using thin layer chromatography (TLC). The intrinsic viscosities (η) were used to differentiate between the different molecular weight of the produced esters1). Tannyl penta stearate is assumed to be the most suitable amphiphilic antioxidant derivative, where those derivatives with less degree of esterification would be less soluble in fat, and those of higher degree of esterification would exhaust more hydroxyl group that cause decreases of antioxidant activity. The structure of tannyl penta stearate was approved depending on its chemical analysis and spectral data (IR, H1 NMR,). The emulsification power of tannyl penta stearate was then determined according to method described by El-Sukkary et al.2), in order to prove its amphiphilic property. Then tannyl penta stearate was tested for its antioxidant and radical scavenging activities in three different manners, those are, lipid oxidation in sunflower oil using Rancimat, (DPPH) free radical scavenging and total antioxidant activity. {Pure tannic acid (T), butylhydroxyanisol (BHA) and butylhydroxytoluene (BHT) were used as reference antioxidant radical saving compounds}. Then tannyl penta stearate was added to sunflower oil, frying process was carried out and all physicochemical parameters of the oil were considered, and compared to other reference antioxidant in order to study the effect of this new antioxidant toward oil stability. Acute oral toxicity of the tannyl penta stearate was carried out using albino mice of 21-25 g body weight to determine its safety according to the method described by Goodman et al.3). Also liver and kidney functions of those mice were checked. Thus it could be concluded that the addition of tannyl penta stearate to frying oils offers a good protection against oxidation. The effectiveness of tannyl penta stearate as lipid antioxidant has been attributed mainly to its stability at high temperature. And according to acute lethal toxicity test tannyl penta stearate was found to be a safe compound that can be used as food additive.


Assuntos
Antioxidantes/síntese química , Emulsificantes/síntese química , Estearatos/síntese química , Taninos/síntese química , Animais , Antioxidantes/farmacologia , Antioxidantes/toxicidade , Compostos de Bifenilo/química , Hidroxianisol Butilado/química , Hidroxitolueno Butilado/química , Emulsificantes/farmacologia , Emulsificantes/toxicidade , Ácidos Graxos/química , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/farmacologia , Depuradores de Radicais Livres/toxicidade , Testes de Função Renal , Testes de Função Hepática , Camundongos , Picratos/química , Ratos , Solubilidade , Estearatos/farmacologia , Estearatos/toxicidade , Ácidos Esteáricos/química , Óleo de Girassol/química , Taninos/química , Taninos/farmacologia , Taninos/toxicidade , Viscosidade
16.
AAPS PharmSciTech ; 18(8): 3236-3246, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28577126

RESUMO

Silibinin (SB) and pomegranate oil (PO) present therapeutic potential due to antioxidant activity, but the biological performance of both bioactives is limited by their low aqueous solubility. To overcome this issue, the aim of the present investigation was to develop nanocapsule suspensions with PO as oil core for SB encapsulation, as well as assess their toxicity in vitro and radical scavenging activity. The nanocapsule suspensions were prepared by interfacial deposition of preformed polymer method. SB-loaded PO-based nanocapsules (SBNC) showed an average diameter of 157 ± 3 nm, homogenous size distribution, zeta potential of -14.1 ± 1.7 mV, pH of 5.6 ± 0.4 and SB content close to 100%. Similar results were obtained for the unloaded formulation (PONC). The nanocapsules controlled SB release at least 10 times as compared with free SB in methanolic solution. The SBNC scavenging capacity in vitro was statistically higher than free SB (p < 0.05). Cell viability in monocytes and lymphocytes was kept around 100% in the treatments with SBNC and PONC, while the SB and the PO caused a decrease around 30% at 50 µM (SB) and 724 µg/mL (PO). Protein carbonyls and DNA damage were minimized by SB and PO nanoencapsulation. Lipid peroxidation occurred in nanocapsule treatments regardless of the SB presence, which may be attributed to PO acting as substrate in reaction. The free compounds also caused lipid peroxidation. The results show that SBNC and PONC presented adequate physicochemical characteristics and low toxicity against human blood cells. Thereby, this novel nanocarrier may be a promising formulation for therapeutic applications.


Assuntos
Citotoxinas/química , Depuradores de Radicais Livres/química , Nanocápsulas/química , Punicaceae , Silimarina/química , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/fisiologia , Células Cultivadas , Citotoxinas/toxicidade , Relação Dose-Resposta a Droga , Depuradores de Radicais Livres/toxicidade , Humanos , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/fisiologia , Peroxidação de Lipídeos/efeitos dos fármacos , Nanocápsulas/toxicidade , Óleos Vegetais/química , Óleos Vegetais/toxicidade , Silibina , Silimarina/toxicidade , Solubilidade
17.
ACS Chem Neurosci ; 8(7): 1618-1627, 2017 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-28421738

RESUMO

Amyloid is a prominent feature of Alzheimer's disease (AD). Yet, a linear linkage between amyloid-ß peptide (Aß) and the disease onset and progression has recently been questioned. In this context, the crucial partnership between Aß and Nrf2 pathways is acquiring paramount importance, offering prospects for deciphering the Aß-centered disease network. Here, we report on a new class of antiaggregating agents rationally designed to simultaneously activate transcription-based antioxidant responses, whose lead 1 showed interesting properties in a preliminary investigation. Relying on the requirements of Aß recognition, we identified the catechol derivative 12. In SH-SY5Y neuroblastoma cells, 12 combined remarkable free radical scavenger properties to the ability to trigger the Nrf2 pathway and induce the Nrf2-dependent defensive gene NQO1 by means of electrophilic activation of the transcriptional response. Moreover, 12 prevented the formation of cytotoxic stable oligomeric intermediates, being significantly more effective, and per se less toxic, than prototype 1. More importantly, as different chemical features were exploited to regulate Nrf2 and Aß activities, the two pathways could be tuned independently. These findings point to compound 12 and its derivatives as promising tools for investigating the therapeutic potential of the Nrf2/Aß cellular network, laying foundation for generating new drug leads to confront AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Catecóis/farmacologia , Depuradores de Radicais Livres/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Fragmentos de Peptídeos/metabolismo , Agregação Patológica de Proteínas/tratamento farmacológico , Doença de Alzheimer/metabolismo , Catecóis/química , Catecóis/toxicidade , Linhagem Celular Tumoral , Desenho de Drogas , Depuradores de Radicais Livres/química , Depuradores de Radicais Livres/toxicidade , Humanos , Peróxido de Hidrogênio/toxicidade , Estrutura Molecular , Estresse Oxidativo/efeitos dos fármacos , Agregação Patológica de Proteínas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Int J Biol Macromol ; 101: 996-1003, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28359887

RESUMO

The preparation of aminoethyl hydroxypropyl starch collagen peptide (AEHPS-COP) was via an enzyme-catalyzed reaction between amino groups in aminoethyl hydroxypropyl starch (AEHPS) and γ-carboxamide groups in collagen peptide (COP) by using microbial transglutaminase (MTGase) as biocatalyst. As an intermediate reactant, AEHPS was synthesized from hydroxypropyl starch (HPS) and 2-chloroethylamine hydrochloride (CEH). The chemical structures of HPS, AEHPS and AEHPS-COP were characterized by Fourier transform infrared spectroscopy (FT-IR) and 13C nuclear magnetic resonance (13C NMR). The reaction conditions that influenced the degree of substitution (DS) of AEHPS-COP were optimized, which included the reaction temperature, the reaction time, the mass ratio of collagen peptide to aminoethyl hydroxypropyl starch and the pH value. In addition, in vitro antioxidant activities of AEHPS-COP were evaluated through the scavenging activity of hydroxyl and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. Furthermore, the methylthiazol tetrazolium (MTT) assay was applied to investigate the cell viability of AEHPS-COP. The results indicated that the AEHPS-COP exhibited better cell viability to L929 mouse fibroblast cells. Therefore, the AEHPS-COP showed a promising potential application in cosmetic, biomedical and pharmaceutical fields.


Assuntos
Colágeno/química , Depuradores de Radicais Livres/química , Fragmentos de Peptídeos/química , Amido/análogos & derivados , Animais , Sobrevivência Celular/efeitos dos fármacos , Etilaminas/química , Depuradores de Radicais Livres/síntese química , Depuradores de Radicais Livres/toxicidade , Ratos , Amido/síntese química , Amido/química , Amido/toxicidade
19.
BMC Complement Altern Med ; 17(1): 55, 2017 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-28100224

RESUMO

BACKGROUND: Lagerstroemia speciosa (L.) Pers. has medicinal importance. Bioactive phytochemicals isolated from different parts of L. speciosa, have revealed hypoglycemic, antibacterial, anti-inflammatory, antioxidant and hepato protective properties. Despite one report from Philippines detailing the use of L. speciosa as curative for fever and as well as diuretic, there is no experimental evidence about the hepatoprotective activity of the flower extracts. METHODS: Several spectroscopic methods, including GC-MS, were used to characterize phytochemicals present in the petal extract of L. speciosa. Ethanol extract of petals was evaluated for anti-oxidant and free radical scavenging properties by using methods related to hydrogen atom transfer, single electron transfer, reducing power, and metal chelation. This study has also revealed the in vitro antioxidant and in vivo hepatoprotective properties of petal extract against carbon tetra chloride (CCl4)-induced liver toxicity in Swiss albino mice. Hepatoprotection in CCl4 -intoxicated mice was studied with the aid of histology and different enzymatic and non-enzymatic markers of liver damage. Cytotoxicity tests were done using murein spleenocytes and cancareous cell lines, MCF7 and HepG2. RESULT: GCMS of the extract has revealed the presence of several potential antioxidant compounds, of them γ-Sitosterol and 1,2,3-Benzenetriol (Pyrogallol) were the predominant ones. The antioxidants activities of the flower-extract were significantly higher than curcumin (in terms of Nitric oxide scavenging activity; p = 0.0028) or ascorbic acid (in terms of 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) assay; p = 0.0022). The damage control by the flower extract can be attributed to the reduction in lipid peroxidation and restoration of catalase activity. In vitro cytotoxicity tests have shown that the flower extract did not affect growth and survivability of the cell lines. It left beyond doubt that a flower of L. speciosa is a reservoir of antioxidant and hepatoprotective agents capable of reversing the damage inflicted by CCl4-intoxication. CONCLUSION: Results from the present study may be used in developing a potential hepato-protective health drink enriched with antioxidants from Lagerstroemia speciosa (L.) Pers.


Assuntos
Depuradores de Radicais Livres/farmacologia , Lagerstroemia/química , Fígado/efeitos dos fármacos , Extratos Vegetais/farmacologia , Substâncias Protetoras/farmacologia , Animais , Antioxidantes/farmacologia , Tetracloreto de Carbono , Linhagem Celular Tumoral , Feminino , Flores/química , Depuradores de Radicais Livres/toxicidade , Células Hep G2 , Humanos , Lagerstroemia/toxicidade , Masculino , Camundongos , Extratos Vegetais/toxicidade
20.
Toxicology ; 376: 126-136, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27234318

RESUMO

Antarctica moss Sanionia uncinata (Hedw.) Loeske is exposed in situ to damaging levels of ultraviolet (UV) radiation. This moss has the ability to respond to UV radiation exposure producing secondary metabolites such as flavonoids, and has been recommended as a potential source of photoprotective compounds and antioxidants. The aim of the present paper was to investigate the free-radical scavenging activity and mutagenic and photomutagenic properties of methanolic (ME), hydroethanolic (HE) and ethanolic (EE) extracts of S. uncinata. The phenolic contents were evaluated by high-performance liquid chromatography (HPLC) and spectrophotometry. The findings showed that ME and EE presented the highest phenolic contents and inhibited free radical-scavenging activity against 2,2'-diphenyl-1 picrylhydrazyl (DPPH) and the HPLC analysis indicated several classes of phenolic acids and flavonoids. The sun protection factors (SPF) were determined by an in vitro method and the results showed significant values. The SPF values of BZ-3 at 50µg/mL increased significantly in association with ME, HE and EE. The extracts did not induce mutagenicity in auxotrophic Salmonella typhimurium histidine and photomutagenicity was not detected in the TA102 and TA104 strains after exposure to UV-A at doses of up to 6.5J/cm2 for the TA102 strain and up to 0.24J/cm2 for the TA104 strain. In addition, with the exception of ME, all the extracts induced photoprotective effects in the presence of the TA104 strain at 0.04J/cm2. The present results suggest that S. uncinata extracts did not induce photomutation and showed promise for photoprotection against the photobiological and ROS-inducing effects of the UV-A radiation.


Assuntos
Briófitas , Extratos Vegetais/efeitos da radiação , Protetores Solares/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Animais , Regiões Antárticas , Relação Dose-Resposta a Droga , Depuradores de Radicais Livres/isolamento & purificação , Depuradores de Radicais Livres/efeitos da radiação , Depuradores de Radicais Livres/toxicidade , Testes de Mutagenicidade/métodos , Mutagênicos/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade , Ratos , Salmonella typhimurium , Protetores Solares/isolamento & purificação , Protetores Solares/toxicidade
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