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1.
J R Soc Interface ; 19(193): 20220391, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35919982

RESUMO

Phosphate and sulfate groups are integral to energy metabolism and introduce negative charges into biological macromolecules. One purpose of such modifications is to elicit precise binding/activation of protein partners. The physico-chemical properties of the two groups, while superficially similar, differ in one important respect-the valency of the central (phosphorus or sulfur) atom. This dictates the distinct properties of their respective esters, di-esters and hence their charges, interactions with metal ions and their solubility. These, in turn, determine the contrasting roles for which each group has evolved in biological systems. Biosynthetic links exist between the two modifications; the sulfate donor 3'-phosphoadenosine-5'-phosphosulfate being formed from adenosine triphosphate (ATP) and adenosine phosphosulfate, while the latter is generated from sulfate anions and ATP. Furthermore, phosphorylation, by a xylosyl kinase (Fam20B, glycosaminoglycan xylosylkinase) of the xylose residue of the tetrasaccharide linker region that connects nascent glycosaminoglycan (GAG) chains to their parent proteoglycans, substantially accelerates their biosynthesis. Following observations that GAG chains can enter the cell nucleus, it is hypothesized that sulfated GAGs could influence events in the nucleus, which would complete a feedback loop uniting the complementary anionic modifications of phosphorylation and sulfation through complex, inter-connected signalling networks and warrants further exploration.


Assuntos
Vias Biossintéticas , Glicosaminoglicanos , Trifosfato de Adenosina/metabolismo , Ésteres , Glicosaminoglicanos/química , Fosforilação , Sulfatos/metabolismo
2.
Bioprocess Biosyst Eng ; 34(3): 253-61, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21072543

RESUMO

Agaricus blazei is a mushroom that belongs to the Brazilian biodiversity and is considered as an important producer of bioactive compounds beneficial to human health. Studies have demonstrated that these compounds present immuno-modulatory, antioxidant and antitumor properties. In order to compare the most used method for fungal polysaccharide drying, lyophilization with other industrial-scale methods, the aim of this work was to submit A. blazei LPB 03 polysaccharide extracts to vaucum, spray and freeze drying, and evaluate the maintenance of its antitumoral effects in vitro. Exopolysaccharides produced by A. blazei LPB 03 on submerged fermentation were extracted with ethanol and submitted to drying processes. The efficiency represents the water content that was removed during the drying process. The resultant dried products showed water content around 3% and water activity less than 0.380, preventing therefore the growth of microorganisms and reactions of chemical degradation. Exopolysaccharide extracts dried by vacuum and spray dryer did not showed any significant cytotoxic effect on cell viability of Wistar mice macrophages. Content of total sugars and protein decrease after drying, nevertheless, 20 mg/ml of exopolysaccharides dried by spray dryer reached 33% of inhibition rate over Ehrlich tumor cells in vitro.


Assuntos
Agaricus/química , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacologia , Liofilização/métodos , Extratos Vegetais/farmacologia , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Agaricus/crescimento & desenvolvimento , Agaricus/metabolismo , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Fermentação , Proteínas Fúngicas/análise , Macrófagos , Camundongos , Extratos Vegetais/isolamento & purificação , Polissacarídeos/biossíntese , Água/química , Água/metabolismo
3.
Mutat Res ; 701(2): 153-63, 2010 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-20599626

RESUMO

Kaurane diterpenes are considered important compounds in the development of new highly effective anticancer chemotherapeutic agents. Genotoxic effects of anticancer drugs in non-tumour cells are of special significance due to the possibility that they induce secondary tumours in cancer patients. In this context, we evaluated the genotoxic and mutagenic potential of the natural diterpenoid kaurenoic acid (KA), i.e. (-)-kaur-16-en-19-oic acid, isolated from Xylopia sericeae St. Hill, using several standard in vitro and in vivo protocols (comet, chromosomal aberration, micronucleus and Saccharomyces cerevisiae assays). Also, an analysis of structure-activity relationships was performed with two natural diterpenoid compounds, 14-hydroxy-kaurane (1) and xylopic acid (2), isolated from X. sericeae, and three semi-synthetic derivatives of KA (3-5). In addition, considering the importance of the exocyclic double bond (C16) moiety as an active pharmacophore of KA cytotoxicity, we also evaluated the hydrogenated derivative of KA, (-)-kauran-19-oic acid (KAH), to determine the role of the exocyclic bond (C16) in the genotoxic activity of KA. In summary, the present study shows that KA is genotoxic and mutagenic in human peripheral blood leukocytes (PBLs), yeast (S. cerevisiae) and mice (bone marrow, liver and kidney) probably due to the generation of DNA double-strand breaks (DSB) and/or inhibition of topoisomerase I. Unlike KA, compounds 1-5 and KAH are completely devoid of genotoxic and mutagenic effects under the experimental conditions used in this study, suggesting that the exocyclic double bond (C16) moiety may be the active pharmacophore of the genetic toxicity of KA.


Assuntos
Diterpenos/química , Diterpenos/toxicidade , Mutagênicos/toxicidade , Extratos Vegetais/toxicidade , Animais , Linhagem Celular Tumoral , Humanos , Masculino , Camundongos , Testes de Mutagenicidade , Relação Estrutura-Atividade
4.
Food Chem Toxicol ; 46(1): 388-92, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17897764

RESUMO

The genotoxic effect of two tanshinones isolated from roots of Hyptis martiussi Benth (Labiatae) was studied using V79 (Chinese hamster lung) cells by the alkaline comet assay and micronucleus test. Tanshinones were incubated with the cells at concentrations of 1, 3, 6 and 12 microg/mL for 3 h. Tanshinones were shown to be quite strongly genotoxic against V79 cells at all tested concentrations. The data obtained provide support to the view that tanshinones has DNA damaging activity in cultured V79 cells under the conditions of the assays.


Assuntos
Antioxidantes/uso terapêutico , Intoxicação por Tetracloreto de Carbono/prevenção & controle , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Flavonoides/uso terapêutico , Animais , Análise Química do Sangue , Intoxicação por Tetracloreto de Carbono/patologia , Catalase/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Fígado Gorduroso/induzido quimicamente , Fígado Gorduroso/patologia , Glutationa/metabolismo , Glutationa Transferase/metabolismo , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/patologia , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais , Ratos , Ratos Sprague-Dawley , Superóxido Dismutase/metabolismo , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
5.
Braz J Med Biol Res ; 39(6): 801-7, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16751987

RESUMO

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg(-1) day(-1) intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3% for piplartine and 55.1 and 56.8% for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.


Assuntos
Alcaloides/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Benzodioxóis/uso terapêutico , Piper/química , Piperidinas/uso terapêutico , Piperidonas/uso terapêutico , Alcamidas Poli-Insaturadas/uso terapêutico , Sarcoma 180/tratamento farmacológico , Alcaloides/isolamento & purificação , Alcaloides/toxicidade , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Benzodioxóis/isolamento & purificação , Benzodioxóis/toxicidade , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Feminino , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Camundongos , Transplante de Neoplasias , Piperidinas/isolamento & purificação , Piperidinas/toxicidade , Piperidonas/isolamento & purificação , Piperidonas/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Alcamidas Poli-Insaturadas/isolamento & purificação , Alcamidas Poli-Insaturadas/toxicidade , Sarcoma 180/patologia , Baço/efeitos dos fármacos , Baço/patologia
6.
Braz. j. med. biol. res ; 39(6): 801-807, June 2006. ilus, tab
Artigo em Inglês | LILACS | ID: lil-428281

RESUMO

Piplartine {5,6-dihydro-1-[1-oxo-3-(3,4,5-trimethoxyphenyl)-2-propenyl]-2(1H)pyridinone} and piperine {1-5-(1,3)-benzodioxol-5-yl)-1-oxo-2,4-pentadienyl]piperidine} are alkaloid amides isolated from Piper. Both have been reported to show cytotoxic activity towards several tumor cell lines. In the present study, the in vivo antitumor activity of these compounds was evaluated in 60 female Swiss mice (N = 10 per group) transplanted with Sarcoma 180. Histopathological and morphological analyses of the tumor and the organs, including liver, spleen, and kidney, were performed in order to evaluate the toxicological aspects of the treatment with these amides. Administration of piplartine or piperine (50 or 100 mg kg-1 day-1 intraperitoneally for 7 days starting 1 day after inoculation) inhibited solid tumor development in mice transplanted with Sarcoma 180 cells. The inhibition rates were 28.7 and 52.3 percent for piplartine and 55.1 and 56.8 percent for piperine, after 7 days of treatment, at the lower and higher doses, respectively. The antitumor activity of piplartine was related to inhibition of the tumor proliferation rate, as observed by reduction of Ki67 staining, a nuclear antigen associated with G1, S, G2, and M cell cycle phases, in tumors from treated animals. However, piperine did not inhibit cell proliferation as observed in Ki67 immunohistochemical analysis. Histopathological analysis of liver and kidney showed that both organs were reversibly affected by piplartine and piperine treatment, but in a different way. Piperine was more toxic to the liver, leading to ballooning degeneration of hepatocytes, accompanied by microvesicular steatosis in some areas, than piplartine which, in turn, was more toxic to the kidney, leading to discrete hydropic changes of the proximal tubular and glomerular epithelium and tubular hemorrhage in treated animals.


Assuntos
Animais , Feminino , Camundongos , Alcaloides/uso terapêutico , Antineoplásicos Fitogênicos/uso terapêutico , Benzodioxóis/uso terapêutico , Piper/química , Piperidinas/uso terapêutico , Piperidonas/uso terapêutico , Alcamidas Poli-Insaturadas/uso terapêutico , /tratamento farmacológico , Alcaloides/isolamento & purificação , Alcaloides/toxicidade , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/toxicidade , Benzodioxóis/isolamento & purificação , Benzodioxóis/toxicidade , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Rim/efeitos dos fármacos , Rim/patologia , Fígado/efeitos dos fármacos , Fígado/patologia , Transplante de Neoplasias , Piperidinas/isolamento & purificação , Piperidinas/toxicidade , Piperidonas/isolamento & purificação , Piperidonas/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/uso terapêutico , Extratos Vegetais/toxicidade , Raízes de Plantas/química , Alcamidas Poli-Insaturadas/isolamento & purificação , Alcamidas Poli-Insaturadas/toxicidade , /patologia , Baço/efeitos dos fármacos , Baço/patologia
7.
Rev. bras. farmacogn ; 11(1): 37-50, 2001. ilus, tab
Artigo em Português | LILACS | ID: lil-528790

RESUMO

A padronização de um fitoterápico é etapa imprescindível para garantia da qualidade de medicamentos contendo plantas medicinais. Objetivou-se padronizar Syzygiam cumini (L.) Skeels e para tanto se estabeleceram parametros tais como, avaliação morfoanatômica das folhas, morfológica das flores e dos frutos, avaliação granulométrica da droga rasurada (frutos), determinação da umidade, avaliação dos processos de secagem, determinação do teor de extrativos e do teor de taninos (monômeros e polimeros). O estudo anatômico das folhas revelou a inexistência de pêlos no sistema dérmico, assim como a ocorrência de glândulas secretoras, drusas, colênquima e esclerênquima. As flores são hermafroditas, com androceu polistêmone e gineceu com ovário ínfero, gamocarpelar, bilocular com placentação axial. Observou-se elevado teor extrativo (38,57 por cento). O diâmetro médio de partícula dos frutos secos moídos ficou em 0,630 mm. O processo de secagem dos frutos influenciou o teor de taninos totais. O teor de taninos determinado ficou em 5,10 por cento para monômeros e 11,30 por cento para os polimeros.


The phytotherapics standardization is an important step for the warranty of the quality of the drugs contends medicinal plants. The aim of this paper was to standardize and establish parameters seeking the characterization of the drug, according to technical pharmacopoeias and in some cases, other techniques were developed. Morphologic description of leaves, flowers and fruits, granulometric analysis of the ground drugs, dry residues, evaluations in the drying methods, determination of the extractive drift and tannins values (monomers and polymers) were executed, being the monomers in the range of 5,10 percent and 11,30 percent for the polymeric ones.

8.
Phytochemistry ; 41(1): 217-23, 1996 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8588867

RESUMO

The steam volatile components from the hexane extract of dried flower buds of Egletes viscosa were identified by gas chromatography-mass spectrometry as trans-carvyl acetate, cis-carvyl acetate, sabinyl acetate, verbenyl acetate, cyclopentaethylidene, geranyl acetate and 5-methylfuranone, and trans-pinocarvyl acetate (major component). From the non-volatile residue, centipedic acid and a novel clerodane diterpene, 12-acetoxy-hawtriwaic acid lactone, were isolated. From the ethanol extract, ternatin (4',5-dihidroxy-3,3',7,8-tetramethoxyflavone), was isolated. Ternatin showed anti-inflammatory, hepatoprotection and gastroprotection properties, and, according to the NCI protocols, it showed moderate activity against HIV. The diterpenes showed antispasmodic activity. Structure determination of these secondary metabolites was accomplished by spectrometric methods, including 2D NMR, chemical interconversion and X-ray crystallographic analysis.


Assuntos
Antivirais/química , Flavonoides/química , HIV/efeitos dos fármacos , Plantas Medicinais , Terpenos/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/isolamento & purificação , Anti-Inflamatórios não Esteroides/farmacologia , Antivirais/isolamento & purificação , Antivirais/farmacologia , Brasil , Cristalografia por Raios X , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Flavonoides/isolamento & purificação , Flavonoides/farmacologia , Humanos , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Modelos Moleculares , Estrutura Molecular , Parassimpatolíticos/química , Parassimpatolíticos/isolamento & purificação , Parassimpatolíticos/farmacologia , Extratos Vegetais , Relação Estrutura-Atividade , Terpenos/isolamento & purificação , Terpenos/farmacologia
9.
Rev Fr Mal Respir ; 9(3): 241-56, 1981.
Artigo em Francês | MEDLINE | ID: mdl-7302347

RESUMO

This study on workers in a uranium mine is principally concerned with the characteristics of the cells recovered by LBA. First, alveolar macrophage function was studied (including viability, phagocytic activity, capillary adherence and migratory activity). Secondly the lymphocytes were identified as T, B, and then their mitogenic responses were studied; occurring spontaneously or in response to phytohemagglutinin or purified protein derivative. Finally, the biochemical aspects were examined (including immunoglobulins, total protein, albumin, phospholipids, potassium, calcium, magnesium, complement components, anti-proteases, etc.). We conclude that there were not demonstrable changes in cellular function in either smokers or non smokers in miners subjected to the ambient radiation of a uranium mine.


Assuntos
Pneumopatias/etiologia , Pulmão/patologia , Mineração , Doenças Profissionais/patologia , Urânio/efeitos adversos , Inibição de Migração Celular , Humanos , Macrófagos/fisiologia , Masculino , Fumar , Irrigação Terapêutica
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