RESUMEN
Purpose: To explore the mechanism of jatrorrhizine on apoptosis and fibrosis induced by myocardial infarction (MI) in an animal model. Methods: The left anterior descending branch of coronary artery was surgically ligated to duplicate the mouse model of MI. The sham and infarcted mice were treated with normal saline once a day, while mice in experimental groups received low-dose (LD) and high-dose (HD) jatrorrhizine once a day respectively. Two weeks later, cardiac function was detected by echocardiography, and histopathological examination was performed using hematoxylin and eosin (H&E) and Masson staining. The expressions of p53, TGF-ß1, Smad/2/3, Bax, Bcl-2, collagen I and collagen III were quantified using qRT-PCR and western blot assays. Results: Jatrorrhizine significantly improved left ventricular ejection fraction (LVEF) and left ventricle end-systolic (LVES) in mice. Histopathological, administration of jatrorrhizine weakened infiltration of inflammatory cells and cardiac fibrosis in myocardium of mice caused by MI. Additionally, jatrorrhizine suppressed cardiomyocyte apoptosis exhibited as its capability to reverse changes of Bax and Bcl-2 levels in myocardium caused by MI. Jatrorrhizine statistically significantly downregulated expression of collagen I and collagen III, as well as TGF-ß1, Smad2/3 and p53. Conclusions: Jatrorrhizine reduce cardiomyocyte apoptosis and fibrosis through inhibiting p53/Bax/Bcl-2 and TGF-ß1/Smad2/3 signaling pathways.
Asunto(s)
Animales , Ratones , Alcaloides de Berberina/análisis , Fibrosis/tratamiento farmacológico , Apoptosis/efectos de los fármacos , Infarto del Miocardio/tratamiento farmacológicoRESUMEN
Rhipicephalus microplus is responsible for high economic losses in livestock and its control has become difficult due to the establishment of tick populations resistant to commercial acaricides. This study aimed to evaluate the in vitro larvicidal effect of the alkaloids berberine and piperine, and also to investigate their inhibitory mechanisms against the acetylcholinesterase enzyme. The effects of the alkaloids on larvae were observed through the immersion test at the following concentrations: 1.5; 3; 6; 12; 16 and 24 mM. Berberine and piperine presented larvicidal activity greater than 95 %, not differing from 100 % for the positive fipronil control (p > 0.05). Of the two alkaloids, piperine had a lower effective concentration (EC), with an EC50 of 6.04 mM. The acetylcholinesterase enzyme used in the study was obtained from R. microplus larvae (RmAChE) and the anticholinesterase activity was determined spectrophotometrically. The highest anticholinesterase activity, measured as inhibition concentration (IC), was observed for berberine (IC50 = 88.13 µM), while piperine showed lower activity (IC50 > 200 µM). Docking studies in RmAChE, followed by 10 ns molecular dynamics simulation, suggest that berberine stabilizes the RmAChE at lower Root-Mean-Square Deviation (RMSD) than Apo protein. Few hydrogen-bond interactions between berberine and RmAChE residues were balanced by hydrophobic and π-type interactions. Berberine fills preferentially the peripheral anionic site (PAS), which correlates with its non-competitive mechanism. These results suggest that berberine and piperine alkaloids have an in vitro acaricidal action on R. microplus larvae, and the likely mechanism of action of berberine is related to RmAChE inhibition when accessing the PAS residues. These findings could help the study of new natural products that could inhibit RmAChE and aid in the development of new acaricides.
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Acaricidas/farmacología , Alcaloides/farmacología , Benzodioxoles/farmacología , Alcaloides de Berberina/farmacología , Piperidinas/farmacología , Extractos Vegetales/farmacología , Alcamidas Poliinsaturadas/farmacología , Rhipicephalus/efectos de los fármacos , Control de Ácaros y Garrapatas , Animales , Inhibidores de la Colinesterasa/farmacología , Simulación por Computador , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Rhipicephalus/crecimiento & desarrolloRESUMEN
BACKGROUND: The impaired glucose tolerance (IGT) is a representative prediabetes characterized by defective glucose homeostasis, and palmatine (PAL) is a natural isoquinoline alkaloid with multiple pharmacological effects. Our study aims to investigate the therapeutic effect of PAL on the impaired glucose tolerance. METHODS: Male Sprague-Dawley rats were used to establish an IGT model with high fat diet (HFD). Oral glucose tolerance test (OGTT) and further biochemical analysis were conducted to determine the effect of PAL on glucose intolerance in vivo. Molecular details were clarified in a cellular model of IGT induced by Palmitate (PA) on INS-1 cells. RESULTS: Our study demonstrated a relief of IGT with improved insulin resistance in HFD induced rats after PAL treatment. Besides, promoted pancreas islets function was validated with significantly increased ß cell mass after the treatment of PAL. We further found out that PAL could alleviate the ß cell apoptosis that accounts for ß cell mass loss in IGT model. Moreover, MAPK signaling was investigated in vivo and vitro with the discovery that PAL regulated the MAPK signaling by restricting the ERK and JNK cascades. The insulin secretion assay indicated that PAL significantly promoted the defective insulin secretion in PA-induced INS-1 cells via JNK rather than ERK signaling. Furthermore, PAL treatment was determined to significantly suppress ß cell apoptosis in PA-induced cells. We thus thought that PAL promoted the PA-induced impaired insulin release by inhibiting the ß cell apoptosis and JNK signaling in vitro. CONCLUSION: In summary, PAL ameliorates HFD-induced IGT with novel mechanisms.
Asunto(s)
Alcaloides de Berberina/farmacología , Dieta Alta en Grasa/efectos adversos , Intolerancia a la Glucosa/tratamiento farmacológico , Resistencia a la Insulina , Animales , Glucemia , Insulina , Masculino , Ratas , Ratas Sprague-DawleyRESUMEN
COVID-19 has become disastrous for world and spread all over. Researchers all around the globe are working to discover a drug to cure from COVID-19. RNA dependent RNA polymerase plays a key role in SARS-CoV-2 replication and thus it could be a potential target for SARS-CoV-2. This study revealed that Protopine, Allocryptopine and (±) 6- Acetonyldihydrochelerythrine could be potential RdRp inhibitors of SARS-CoV-2.
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Argemone/química , Benzofenantridinas/farmacología , Alcaloides de Berberina/farmacología , Tratamiento Farmacológico de COVID-19 , Extractos Vegetales/uso terapéutico , ARN Polimerasa Dependiente del ARN/antagonistas & inhibidores , Antivirales/farmacología , Simulación por Computador , Reposicionamiento de Medicamentos , Humanos , Conformación Molecular , Simulación del Acoplamiento Molecular , Fenantrenos/farmacología , Fitoquímicos/farmacología , Replicación Viral/efectos de los fármacosRESUMEN
There is evidence that palmatine (PA), an alkaloid isolated from the Guatteria friesiana plant, has some important biological activities, including anti-inflammatory and antidepressant effects. In this study, the antioxidant and anti-acetylcholinesterase (AChE) effects of PA were assessed. The antioxidant capacity was evaluated in vitro and in vivo through 7 distinct assays, and the anti-AChE activity was determined in vitro. The standards, trolox and ascorbic acid were used for the in vitro antioxidant test, while hydrogen peroxide was selected as a stressor for the Saccharomyces cerevisiae test. Additionally, PA was also combined with trolox and ascorbic acid to determine the likelihood of synergistic effects occurrence to what concerns to antioxidant potential. PA exhibited a potent and concentration-dependent antioxidant potential, although a stronger antioxidant activity was stated using the PA + trolox combination. PA was also found to inhibit AChE activity when compared to the negative control. Thus, PA may be viewed as a promissory phytotherapeutic agent to manage oxidative stress-mediated neurological diseases, especially the Alzheimer's and Parkinson's diseases.
Asunto(s)
Acetilcolinesterasa/metabolismo , Antioxidantes/farmacología , Alcaloides de Berberina/farmacología , Inhibidores de la Colinesterasa/farmacología , Peróxido de Hidrógeno/toxicidad , Saccharomyces cerevisiae/efectos de los fármacosRESUMEN
BACKGROUND: The impaired glucose tolerance (IGT) is a representative prediabetes characterized by defective glucose homeostasis, and palmatine (PAL) is a natural isoquinoline alkaloid with multiple pharmacological effects. Our study aims to investigate the therapeutic effect of PAL on the impaired glucose tolerance. METHODS: Male Sprague-Dawley rats were used to establish an IGT model with high fat diet (HFD). Oral glucose tolerance test (OGTT) and further biochemical analysis were conducted to determine the effect of PAL on glucose intolerance in vivo. Molecular details were clarified in a cellular model of IGT induced by Palmitate (PA) on INS-1 cells. RESULTS: Our study demonstrated a relief of IGT with improved insulin resistance in HFD induced rats after PAL treatment. Besides, promoted pancreas islets function was validated with significantly increased ß cell mass after the treatment of PAL. We further found out that PAL could alleviate the ß cell apoptosis that accounts for ß cell mass loss in IGT model. Moreover, MAPK signaling was investigated in vivo and vitro with the discovery that PAL regulated the MAPK signaling by restricting the ERK and JNK cascades. The insulin secretion assay indicated that PAL significantly promoted the defective insulin secretion in PA-induced INS-1 cells via JNK rather than ERK signaling. Furthermore, PAL treatment was determined to significantly suppress ß cell apoptosis in PA-induced cells. We thus thought that PAL promoted the PA-induced impaired insulin release by inhibiting the ß; cell apoptosis and JNK signaling in vitro. CONCLUSION: In summary, PAL ameliorates HFD-induced IGT with novel mechanisms.
Asunto(s)
Animales , Masculino , Ratas , Alcaloides de Berberina/farmacología , Resistencia a la Insulina , Intolerancia a la Glucosa/tratamiento farmacológico , Dieta Alta en Grasa/efectos adversos , Glucemia , Ratas Sprague-Dawley , InsulinaRESUMEN
Introducción: El uso indiscriminado de agentes antiparasitarios ha resultado en el establecimiento de resistencia a ellos. Por lo cual es necesario el desarrollo de nuevas alternativas de tratamiento. Los productos naturales poseen diversas cualidades como posibles coadyuvantes en terapias contra distintos agentes etiológicos, entre los que destaca sus efectos antiparasitarios. Objetivo: Evaluar la actividad antiparasitaria, antioxidante, citotóxica y citoprotectora de Berberina (Ber), Curcumina (Cur) y Quercetina (Qr). Metodología: Se prepararon soluciones de Ber, Cur y Qr grado analítico y se realizaron alícuotas a diferentes concentraciones para su evaluación en contra de: Entamoeba histolytica, Trichomonas vaginalis y Strongyloides venezuelensis, paraello, se determinó la concentración inhibitoria media (IC50), además se determinó la capacidad antioxidante (CE50) mediante la prueba de DPPH, ambos por la prueba de Probit. Mediante la técnica de hemólisis se determinó la actividad citotóxica y citoprotectora, se aplicó Anova y la prueba de Tukey para determinar la diferencia de las medias en los tratamientos evaluados. Resultados: Ber, Cur y Qr, presentaron actividad en contra de E. histolytica, T. vaginalis y S. venezuelensis in-vitro. Ber presentó IC50 de 1.7, 1.2 y 1.9 μM respectivamente siendo más efectivo en comparación de Cur con IC50 de 55.3, 40.6 y 13.7 μM o Qr con IC50 de 147.2, 93.2 y 110.9 μM, sin embargo, la mejor actividad antioxidante (EC50 = 1.1 μg/ml), citoprotectora y menos hemolítica, fue presentada por Qr (P < 0.001) en comparación con el control evaluado. Conclusiones: Los metabolitos de origen natural berberina, curcumina y quercetina, poseen actividad en contra de trofozoítos de E. histolytica, T. vaginalisy larvas de S. venezuelensis en dosis bajas comparables con los fármacos de referencia para el caso de Ber. Además, estos productos de origen natural, no sintético podrían ser objeto de futuras investigaciones para coadyuvar al tratamiento de parasitosis, ya que, en dosis bajas, mostraron actividad antioxidante sin mostrar hemólisis considerable en eritrocitos humanos.
Introduction: The indiscriminate use of antiparasitic agents has resulted in the establishment of resistance to them. Therefore, the development of new treatment alternatives is necessary. Natural products have various qualities as possible adjuvants in therapies against different etiological agents, among which its antiparasitic effects stand out. Objective: To evaluate the antiparasitic, antioxidant, cytotoxic, and cytoprotective activity of Berberine (Ber), Curcumin (Cur), and Quercetin (Qr). Methods: Analytical grade Ber, Cur, and Qr solutions were prepared, and aliquots were made at different concentrations for their evaluation against Entamoeba histolytica, Trichomonas vaginalis, and Strongyloides venezuelensis. To do this, the mean inhibitory concentration (IC50) was determined, and the antioxidant capacity (EC50) was also determined by the DPPH assay, both using the Probit statistical test. The cytotoxic and cytoprotective activity was determined by the hemolysis technique, Anova and Tukey's test were applied to determine the difference in the means in the treatments evaluated. Results: Ber, Cur, and Qr, showed activity against E. histolytica, T. vaginalis, and S. venezuelensisin-vitro. Ber presented IC50 of 1.7, 1.2, and 1.9 μM respectively, being more effective compared to Cur with IC50 of 55.3, 40.6, and 13.7 μM, or Qr with IC50 of 147.2, 93.2, and 110.9 μM, however, the best antioxidant activity (EC50 = 1.1 μg/ml), cytoprotective and less hemolytic, was presented by Qr (P < 0.001) compared to the evaluated control. Conclusions: The metabolites of natural origin berberine, curcumin, and quercetin, have activity against trophozoites of E. histolytica, T. vaginalis and larvae of S. venezuelensis in low doses comparable to the reference drugs in the case of Ber. Furthermore, these non-synthetic products of natural origin could be the subject of future research to help treat parasitosis, since in low doses, they showed antioxidant activity without showing considerable cytotoxicity in human erythrocytes.
Asunto(s)
Quercetina/análisis , Alcaloides de Berberina/análisis , Curcumina/análisis , Polifenoles/análisis , Plantas Medicinales , AntiparasitariosRESUMEN
Tetrahydropyran (THP) rings are common in several natural products, therefore, various strategies are being developed to synthesize these rings. The present work described the study of a one-pot synthesis of 2,4,6-trisubstituted tetrahydropyran compounds promoted by the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate [BMIM][PF6] through a Barbier-Prins reaction between allyl bromide and aldehydes. The use of [BMIM][PF6] gave Prins products from several aldehydes in good yields and reaction times. We also found that the anion, PF6-, accelerates the Barbier reaction when used alone, and the excess SnBr2 from the reaction conditions of the Barbier reaction leads to the formation of the THP rings, thus acting as a catalyst for Prins cyclization. Additionally, we demonstrate that ionic liquid can be recovered and reused five times in the preparation of 4-bromo-tetrahydro-2,6-diphenyl-2H-pyran without significant yield loss.
Asunto(s)
Alcaloides de Berberina/síntesis química , Imidazoles/química , Líquidos Iónicos/química , Catálisis , Técnicas de Química Sintética , Estructura MolecularRESUMEN
Berberis microphylla is a native plant that grows in Patagonia and is commonly used by aboriginal ethnic groups in traditional medicine as an antiseptic for different diseases. The present study evaluated the antibacterial and synergistic activity of alkaloid extracts of B. microphylla leaves, stems and roots used either individually or in combination with antibiotics against Gram-positive and Gram-negative bacteria. The in vitro antibacterial activities of leaf, stem and root alkaloid extracts had significant activity only against Gram-positive bacteria. Disc diffusion tests demonstrated that the root extract showed similar activity against B. cereus and S. epidermidis compared to commercial antibiotics, namely ampicillin and cephalothin, and pure berberine, the principal component of the alkaloid extracts, was found to be active only against S. aureus and S. epidermidis with similar activity to that of the root extract. The minimum inhibitory concentrations (MICs) of the alkaloid extracts ranged from 333 to 83 µg/mL, whereas minimum bactericidal concentrations (MBCs) varied from 717 to 167 µg/mL. In addition, synergistic or indifferent effects between the alkaloid extracts and antibiotics against bacterial strains were confirmed.
Asunto(s)
Ampicilina/farmacología , Antibacterianos/farmacología , Alcaloides de Berberina/farmacología , Berberis/química , Cefalotina/farmacología , Antibacterianos/aislamiento & purificación , Alcaloides de Berberina/aislamiento & purificación , Sinergismo Farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Bacterias Grampositivas/efectos de los fármacos , Bacterias Grampositivas/crecimiento & desarrollo , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Hojas de la Planta/química , Raíces de Plantas/química , Tallos de la Planta/químicaRESUMEN
Leishmaniasis is one of the World's most problematic diseases in developing countries. Traditional medicines to treat leishmaniasis have serious side effects, as well as significant parasite resistance problems. In this work, two alkaloids 1 and 2 were obtained from Corydalis govaniana Wall and seven alkaloids 3-9, were obtained from Erythrina verna. The structures of the compounds were confirmed by mass spectrometry and 1D- and 2D-NMR spectroscopy. The leishmanicidal activity of compounds 1-9 against Leishmania amazonensis was tested on promastigote forms and cytotoxicity against J774 (macrophage cell line) was assessed in vitro. Compound 1 showed potent activity (IC50 = 0.18 µg/mL), compared with the standard amphotericin B (IC50 = 0.20 µg/mL). The spirocyclic erythrina-alkaloids showed lower leishmanicidal activity than dibenzoquinolizine type alkaloids.
Asunto(s)
Alcaloides de Berberina/administración & dosificación , Erythrina/química , Leishmania/parasitología , Leishmaniasis/tratamiento farmacológico , Alcaloides/química , Alcaloides de Berberina/química , Línea Celular , Humanos , Leishmania/efectos de los fármacos , Leishmaniasis/parasitología , Macrófagos/efectos de los fármacos , Macrófagos/patología , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/administración & dosificación , Extractos Vegetales/químicaRESUMEN
Los alcaloides bencilisoquinolínicos (ABI) son metabolitos especializados con una distribución filogenética antigua pero conservadatodavía en clados modernos. Varios de ellos, como la morfina, sanguinerina y berberina tienen importancia en la medicina moderna. Enesta revisión se analizan los aspectos más sobresalientes del estado actual de la biosíntesis de ABI. Se han realizado estudios que hanpermitido conocer la biosíntesis de 22 de estos metabolitos nitrogenados. En su formación participan 43 enzimas agrupadas en oxidoreductasas,transferasas y liasas, que en algunos casos representan ejemplos atípicos de la forma en la que se originó la diversificación delmetabolismo secundario, entre ellos proteínas citocromo P450 (CYP450) con actividades catalíticas para la ruta de los ABI, o la enzimanorcoclaurina sintasa (NCS) que esta emparentada con proteínas alergénicas de defensa. Así mismo, hay avances genéticos en los quese ha podido caracterizar 30 enzimas, permitiendo conocer procesos de regulación. Otro aspecto interesante es la compartimentaciónde los sitios de biosíntesis y acumulación de ABI ya que en varios casos están separados espacialmente y en distintas especies o en lamisma pueden participar varios tipos de células. Ello ha sugerido el transporte intra e intercelular de los alcaloides, los precursores yde las enzimas, se ha documentado el transporte de berberina entre el citoplasma y las vacuolas del almacenamiento. El panorama de labiosíntesis de ABI se ha construido con los estudios de ejemplares de importancia farmacológica...
The benzylisoquinoline alkaloids (BIA) are specialized metabolites with an ancient phylogeneticdistribution, but still preserved in modern clades. Some of them, such as morphine, sanguinerine or berberine, are important for modernmedicine. This review discusses the highlights of the current state of the biosynthesis of BIA. There have been studies that show thebiosynthesis of 22 of these nitrogenous metabolites. In their formation there are 43 enzymes grouped into oxidoreductases, transferasesand lyases, which in some cases represent atypical examples of the manner in which the secondary metabolism diversification wasoriginated. Two of these examples are the cytochrome proteins P450 (P450), with catalytic activities for ABI route, or the norcoclaurinesynthase enzyme (NCS), which share substantial identity with defense allergenic proteins. Likewise, there are genetic advances thathave produced the characterization of 30 enzymes, allowing knowledge of regulatory processes. Another interesting aspect is thecompartmentation of the biosynthesis sites and accumulation of BIA, since in several cases they are spatially separated and in differentspecies, or in the same species several types of cells may be involved. This has suggested intra and intercellular transport of alkaloids,precursors and enzymes, and it has been documented berberine transport between the cytoplasm and the vacuoles of storage. The picturefor the biosynthesis of BIA has been constructed with exemplary studies of alkaloids with pharmacological importance...
Os alcalóides benzilisoquinolinas (ABI) são metabólitos especializados com umadistribuição filogenética antiga, mas ainda preservada em clados modernos. Vários deles, como a morfina, sanguinarina e berberina sãoimportantes na medicina moderna. Neste artigo, se analisam os aspectos mais destacados do estado atual da biossíntese de ABI; há estudosque tem permitido conhecer a biossíntese de 22 desses metabólitos nitrogenados. Na sua síntese participam 43 enzimas agrupadas emoxidoreductases, transferases, liases e, em alguns casos, representam exemplos atípicos da forma pela qual se originou a diversificaçãodo metabolismo secundário, incluindo as proteínas do citocromo P450 (CYP450), com atividades catalíticas para a rota dos ABI, ou aenzima norcoclaurina sintase (NCS), que está relacionada com proteínas alergênicas de defesa. Da mesma forma, há avanços genéticosna caracterização de 30 enzimas, permitindo conhecer processos de regulação. Outro aspecto interessante é a compartimentalização dossítios de biossíntese e acumulação de ABI uma vez que em muitos casos estão separados espacialmente e em diferentes espécies, ou namesma podem participar vários tipos de células. Isto há sugerido o transporte intra e intercelular de alcalóides, precursores das enzimas;tem sido documentado o transporte de berberina entre o citoplasma e os vacúolos de armazenamento. A perspectiva na biossíntese deABI foi construída com os estudos de exemplares de importância farmacológica...
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Alcaloides de Berberina/análisis , Alcaloides/análisis , Alcaloides/biosíntesis , Alcaloides/metabolismo , Alcaloides/sangreRESUMEN
The phytochemical study of Duguetia moricandiana Mart. (Annonaceae) yielded the isolation of the alkaloid which was identified by spectral analysis as discretamine. The evaluation of antinociceptive activity carried out by the acetic acid-induced writhing, formalin and hot plate tests in mice, suggests a potent antinociceptive effect. Discretamine (5, 10 and 20 mg kg⻹, i.p.) significantly reduced the number of writhes similarly at all doses tested and the number of paw licks during the first phase of formalin test when compared to control. The effect of discretamine on hot plate response provides a confirmation of its central effect. These results indicate antinociceptive properties of this alkaloid.
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Analgésicos/farmacología , Annonaceae/química , Alcaloides de Berberina/farmacología , Dolor/tratamiento farmacológico , Extractos Vegetales/química , Ácido Acético , Analgésicos/aislamiento & purificación , Analgésicos/uso terapéutico , Análisis de Varianza , Animales , Alcaloides de Berberina/química , Alcaloides de Berberina/aislamiento & purificación , Alcaloides de Berberina/uso terapéutico , Cromatografía , Relación Dosis-Respuesta a Droga , Formaldehído , Espectroscopía de Resonancia Magnética , Masculino , Ratones , Estructura Molecular , Dimensión del DolorRESUMEN
Berberine, palmatine and dehydrocoreximine are end products of protoberberine biosynthesis. These quaternary protoberberines are elicitor inducible and, like other phytoalexins, are highly oxidized. The oxidative potential of these compounds is derived from a diverse array of biosynthetic steps involving hydroxylation, intra-molecular C-C coupling, methylenedioxy bridge formation and a dehydrogenation reaction as the final step in the biosynthesis. For the berberine biosynthetic pathway, the identification of the dehydrogenase gene is the last remaining uncharacterized step in the elucidation of the biosynthesis at the gene level. An enzyme able to catalyze these reactions, (S)-tetrahydroprotoberberine oxidase (STOX, EC 1.3.3.8), was originally purified in the 1980s from suspension cells of Berberis wilsoniae and identified as a flavoprotein (Amann et al. 1984). We report enzymatic activity from recombinant STOX expressed in Spodoptera frugiperda Sf9 insect cells. The coding sequence was derived successively from peptide sequences of purified STOX protein. Furthermore, a recombinant oxidase with protoberberine dehydrogenase activity was obtained from a cDNA library of Argemone mexicana, a traditional medicinal plant that contains protoberberine alkaloids. The relationship of the two enzymes is discussed regarding their enzymatic activity, phylogeny and the alkaloid occurrence in the plants. Potential substrate binding and STOX-specific amino acid residues were identified based on sequence analysis and homology modeling.
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Argemone/enzimología , Berberis/enzimología , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/biosíntesis , Secuencia de Aminoácidos , Animales , Argemone/genética , Argemone/metabolismo , Secuencia de Bases , Alcaloides de Berberina/metabolismo , Berberis/genética , Berberis/metabolismo , Activación Enzimática , Flavoproteínas/metabolismo , Regulación de la Expresión Génica de las Plantas , Insectos/enzimología , Insectos/genética , Datos de Secuencia Molecular , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/genética , Oxidorreductasas actuantes sobre Donantes de Grupo CH-CH/metabolismo , Filogenia , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/genética , Homología de Secuencia , Sesquiterpenos/metabolismo , Transformación Genética , FitoalexinasRESUMEN
Formation of the methylenedioxy bridge is an integral step in the biosynthesis of benzo[c]phenanthridine and protoberberine alkaloids in the Papaveraceae family of plants. This reaction in plants is catalyzed by cytochrome P450-dependent enzymes. Two cDNAs that encode cytochrome P450 enzymes belonging to the CYP719 family were identified upon interrogation of an EST dataset prepared from 2-month-old plantlets of the Mexican prickly poppy Argemone mexicana that accumulated the benzo[c]phenanthridine alkaloid sanguinarine and the protoberberine alkaloid berberine. CYP719A13 and CYP719A14 are 58% identical to each other and 77% and 60% identical, respectively, to stylopine synthase CYP719A2 of benzo[c]phenanthridine biosynthesis in Eschscholzia californica. Functional heterologous expression of CYP719A14 and CYP719A13 in Spodoptera frugiperda Sf9 cells produced recombinant enzymes that catalyzed the formation of the methylenedioxy bridge of (S)-cheilanthifoline from (S)-scoulerine and of (S)-stylopine from (S)-cheilanthifoline, respectively. Twenty-seven potential substrates were tested with each enzyme. Whereas CYP719A14 transformed only (S)-scoulerine to (S)-cheilanthifoline (K(m) 1.9±0.3; k(cat)/K(m) 1.7), CYP719A13 converted (S)-tetrahydrocolumbamine to (S)-canadine (K(m) 2.7±1.3; k(cat)/K(m) 12.8), (S)-cheilanthifoline to (S)-stylopine (K(m) 5.2±3.0; k(cat)/K(m) 2.6) and (S)-scoulerine to (S)-nandinine (K(m) 8.1±1.9; k(cat)/K(m) 0.7). These results indicate that although CYP719A14 participates in only sanguinarine biosynthesis, CYP719A13 can be involved in both sanguinarine and berberine formation in A. mexicana.
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Antibacterianos/metabolismo , Argemone/enzimología , Benzofenantridinas/metabolismo , Alcaloides de Berberina/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Isoquinolinas/metabolismo , Argemone/genética , Argemone/metabolismo , Bencilisoquinolinas/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Datos de Secuencia Molecular , FilogeniaRESUMEN
Four quaternary isoquinoline alkaloids, dehydrocorydalmine, jatrorrhizine, columbamine, and oxyberberine, have been isolated from the whole plant of Argemone mexicana Linn. (Papaveraceae) and their structures established by spectral evidence. This is the first report of these alkaloids (dehydrocorydalmine, jatrorrhizine, columbamine, and oxyberberine) from Argemone mexicana and the Argemone genus.
Asunto(s)
Alcaloides , Argemone/química , Isoquinolinas , Alcaloides/análisis , Alcaloides/química , Alcaloides/aislamiento & purificación , Alcaloides de Berberina/análisis , Alcaloides de Berberina/química , Alcaloides de Berberina/aislamiento & purificación , Isoquinolinas/análisis , Isoquinolinas/química , Isoquinolinas/aislamiento & purificación , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Estructura Molecular , Espectrofotometría Ultravioleta , Temperatura de TransiciónRESUMEN
The aim of this study was to investigate the pharmacological effects of discretamine, an isoquinoline alkaloid isolated from Duguetia magnolioidea Maas, on the cardiovascular system, using a combined in vivo and in vitro approach. Blood pressure and heart rate measurements, as well as changes in isometric tension in rat superior mesenteric arterial rings, elicited by discretamine were recorded. In normotensive non-anaesthetized rats (n = 6), discretamine (0.01; 0.05; 0.1; 0.5; 1, 5 and 10 mg/kg i.v., randomly) injections produced hypotension (-5.2 +/- 1.7; -5.1 +/- 2.1; -7.7 +/- 2; -8.9 +/- 1.7; -9.6 +/- 2.2; -16.8 +/- 2.8 and -13.4 +/- 1.3 mmHg, respectively) accompanied by tachycardia (24.2 +/- 6.1; 36.8 +/- 11.3; 44.2 +/- 7.7; 45.9 +/- 6.4; 48.2 +/- 9.1; 72.1 +/- 14.5 and 64 +/- 17 bpm, respectively). Hypotensive and tachycardic responses were significantly attenuated after L-NAME (20 mg/kg, i.v.) administration. In isolated rat mesenteric artery rings, with endothelium intact, discretamine (10(-12) - 10(-5) M) induced concentration-dependent relaxation of the contractions induced by phenylephrine (10 microM) [pD2 = 6.8 +/- 0.1]. The effect of the discretamine on phenylephrine induced contractions was significantly attenuated after removal of the vascular endothelium [pD2 = 5.8 +/- 0.04]. Similar results were obtained after pre-treatment with L-NAME 100 microM [pD2 = 5.8 +/- 0.04], L-NAME 300 microM [pD2 = 5.9 +/- 0.06], Hydroxocobalamin 30 microM [pD2 = 5.8 +/- 0.06] or ODQ 10 microM [pD2 = 5.8 +/- 0.04]. In addition, in rabbit aorta endothelial cell line, discretamine significantly increased NO3- levels. These results suggest that the hypotensive effect induced by discretamine is probably due to a peripheral vasodilatation, at least, in part, due to the release of NO from vascular endothelium and consequent activation of soluble guanylyl cyclase (GC) in the vascular smooth muscle cells.
Asunto(s)
Antihipertensivos/farmacología , Alcaloides de Berberina/farmacología , Endotelio Vascular/fisiología , Factores Relajantes Endotelio-Dependientes/fisiología , Músculo Liso Vascular/efectos de los fármacos , Óxido Nítrico/fisiología , Animales , Presión Sanguínea/efectos de los fármacos , Células Cultivadas , Endotelio Vascular/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Masculino , Arterias Mesentéricas/efectos de los fármacos , Relajación Muscular/efectos de los fármacos , Óxido Nítrico/metabolismo , Conejos , Ratas , Ratas WistarRESUMEN
Ukrain is a reaction product of different alkaloids from Chelidonium majus L. (celandine) conjugated with thiophosphoric acid. It has immunoregulatory effects on T lymphocyte subsets and cytotoxic and cytostatic effects on various malignant cells. Although Ukrain has been reported to induce alterations in the cell cycle and tubulin polymerization, the specific cellular target has not been described. Since antineoplasic agents induce NF-kappaB and their effects are regulated by this transcription factor, we investigated its possible participation in the apoptotic effects of Ukrain. Ukrain induced apoptosis in a panel of cancer cell lines by activating the intrinsic cell death pathway, as demonstrated by the cleavage of caspase 9 and the upregulation and cleavage of caspase 3. The effect was reversible, since long exposures (24 hours or more) were needed, as verified by clonogenic assays. Gene reporter assays showed that Ukrain activated NF-kappa B. Nevertheless, this activation was not required for, and did not modulate, the Ukrain effect: neither blockage of activation by a dominant negative version of Ikappa-B alpha or a Bcl-3 siRNA, nor activation of the pathway by overexpression of IKK2, changed the response to the drug. In conclusion, Ukrain induced apoptosis in HeLa cervical cancer cells by activating the intrinsic pathway. In contrast to other antineoplasic drugs, the effects of Ukrain were not regulated by NF-kappa B.
Asunto(s)
Antineoplásicos/farmacología , Apoptosis , Alcaloides de Berberina/farmacología , FN-kappa B/metabolismo , Neoplasias/metabolismo , Fenantridinas/farmacología , Proteínas del Linfoma 3 de Células B , Caspasa 3/análisis , Caspasa 3/metabolismo , Caspasa 9/análisis , Caspasa 9/metabolismo , Línea Celular Tumoral , Expresión Génica , Genes Reporteros , Humanos , Quinasa I-kappa B/antagonistas & inhibidores , Quinasa I-kappa B/genética , Quinasa I-kappa B/metabolismo , FN-kappa B/agonistas , FN-kappa B/análisis , Neoplasias/genética , Neoplasias/patología , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Proto-Oncogénicas/genética , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/farmacología , Factores de Transcripción/antagonistas & inhibidores , Factores de Transcripción/genéticaRESUMEN
Different classes of topoisomerase (TOP) inhibitors and antitrypanosomatid agents exhibited variable efficacies against Leishmania donovani parasites and human mononuclear cells both at the level of DNA topoisomerase I (TOPI) catalytic activity and in cytotoxicity assays. Bis-benzimidazoles and the diamidine diminazene aceturate exhibited uniformly high efficacies against parasite and host enzymes as well as against parasite and mononuclear cells, but pentamidine showed around 2 orders of magnitude greater specificity for Leishmania TOPI and amastigote cells (P<0.05). The protoberberine coralyne and the flavonoid quercetin were highly potent, but non-selective, inhibitors in vitro, although the latter showed slight selectivity for parasite TOPI. Camptothecin was selective for mononuclear cells at both levels (P<0.05) and sodium stibogluconate was selective only at the enzyme level displaying 30-fold greater potency against parasite TOPI (P<0.05). These data suggest that at least part of pentamidines' leishmanicidal activity may be mediated through TOPI inhibition, and support the feasibility of exploiting differences between Leishmania and human TOPs to develop modified compounds with improved selectivity.