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1.
Environ Monit Assess ; 195(6): 725, 2023 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-37227526

RESUMEN

Events of climate change have led to increased aridification, which alters local vegetation patterns and results in the invasion of opportunistic species. Though many studies assess the impact of invasive weeds and aridification at the agronomic level, studies investigating changes in local vegetation are severely lacking. We investigated the impact of the invasive plant Verbesina encelioides (Asteraceae) on the local vegetation composition across different dryland ecosystems in Punjab, northwestern India. Based on the aridity index for the period of 1991-2016, three major dryland ecosystems, i.e., arid, semi-arid, and sub-humid, were found in Punjab. The impact of V. encelioides on local biodiversity was measured in terms of species diversity (using Shannon's diversity index, Simpson's dominance index, Hill's evenness index, and Margalef's richness index), species composition (using non-metric multidimensional scaling based on Bray-Curtis's dissimilarity index), and species proportion in the two invasion classes (uninvaded and invaded) and across the three aridity zones (arid, semi-arid, and sub-humid). The vegetation survey depicted the presence of 53 flowering species belonging to 22 families, including 30 exotics and 23 natives. Verbesina encelioides decreased species diversity and proportion, with a more pronounced impact in arid and semi-arid ecosystems. In contrast, species composition varied between uninvaded and invaded classes only in arid ecosystems. Ecological parameters derived from population statistics (number of individuals) were more drastically affected than those from species abundance data. Since the ecological impacts of V. encelioides were manifested with increased aridification, it is a matter of apprehension under the potential climate change scenario.


Asunto(s)
Ecosistema , Verbesina , Humanos , Malezas , Monitoreo del Ambiente , Biodiversidad
2.
Planta Med ; 88(14): 1341-1347, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35468649

RESUMEN

Cryptococcus neoformans is an opportunistic fungal pathogen that has limited treatment options. Natural product plant extracts offer a cost-effective option for the discovery of new anticryptococcal lead compounds. The acetone bark extract of Verbesina turbacensis was found to potently inhibit C. neoformans and was subjected to bioautography. Two compounds that inhibited the growth of C. neoformans were isolated and displayed minimum inhibitory concentration values of 10 and 310 µg/mL. The compounds were identified as the bornyl hydroxycinnamic esters bornyl caffeate and bornyl ferulate, respectively. To better understand initial structure-activity relationships, anticryptococcal activity was characterized for similar compounds. All compounds were further evaluated for mammalian cell toxicity using the MTT assay with MCF-7 and HEK-293 cell lines. Overall, bornyl caffeate demonstrated promising anticryptococcal potential given its potent inhibition of C. neoformans and low mammalian cell toxicity.


Asunto(s)
Cryptococcus neoformans , Verbesina , Animales , Humanos , Células HEK293 , Relación Estructura-Actividad , Antifúngicos/farmacología , Mamíferos
3.
BMC Complement Altern Med ; 16: 126, 2016 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-27161012

RESUMEN

BACKGROUND: Cancer is a major health problem and exploiting natural products have been one of the most successful methods to combat this disease. Verbesina encelioides is a notorious weed with various pharmacological properties. The aim of the present investigation was to screen the anticancer potential of V. encelioides extract against human lung cancer (A-549), breast cancer (MCF-7), and liver cancer (HepG2) cell lines. METHODS: A-549, MCF-7, and HepG2 cells were exposed to various concentrations of (10-1000 µg/ml) of V. encelioides for 24 h. Further, cytotoxic concentrations (250, 500, and 1000 µg/ml) of V. encelioides induced oxidative stress (GSH and LPO), reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest, and DNA damage in HepG2 cells were studied. RESULTS: The exposure of cells to 10-1000 µg/ml of extract for 24 h, revealed the concentrations 250-1000 µg/ml was cytotoxic against MCF-7 and HepG2 cells, but not against A-549 cells. Moreover, the extract showed higher decrease in the cell viability against HepG2 cells than MCF-7 cells. Therefore, HepG2 cells were selected for further studies viz. oxidative stress (GSH and LPO), reactive oxygen species (ROS) generation, mitochondrial membrane potential (MMP), cell cycle arrest, and DNA damage. The results revealed differential anticancer activity of V. encelioides against A-549, MCF-7 and HepG2 cells. A significant induction of oxidative stress, ROS generation, and MMP levels was observed in HepG2 cells. The cell cycle analysis and comet assay showed that V. encelioides significantly induced G2/M arrests and DNA damage. CONCLUSION: These results indicate that V. encelioides possess substantial cytotoxic potential and may warrant further investigation to develop potential anticancer agent.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Puntos de Control del Ciclo Celular/efectos de los fármacos , Daño del ADN , Extractos Vegetales/farmacología , Verbesina/química , Línea Celular Tumoral , Ensayos de Selección de Medicamentos Antitumorales , Glutatión/metabolismo , Células Hep G2 , Humanos , Peroxidación de Lípido , Neoplasias Hepáticas , Potencial de la Membrana Mitocondrial , Oxidación-Reducción , Especies Reactivas de Oxígeno/metabolismo
4.
Bioorg Med Chem ; 23(17): 5816-28, 2015 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-26190458

RESUMEN

The anti-inflammatory and antiproliferative activities of 4ß-cinnamoyloxy,1ß,3α-dihydroxyeudesm-7,8-ene (1) and of three derivatives, namely diacetate (2), hydrogenate (3) and diacetate hydrogenate (4) were evaluated. All derivatives exert an anti-inflammatory effect significantly lower than that exerted by 1. Otherwise, both the lead compound and 2-4 showed a comparable antiproliferative activity on human tumor cell lines. The investigation of the mechanism of action accountable for cytotoxicity highlighted the capacity to impair mitochondrial functions through two different pathways, depending on chemical structure. In particular, the lead compound 1 and derivative 3 are able to induce mitochondrial permeability transition, while derivatives 2 and 4 inhibit Complex II in the respiratory chain.


Asunto(s)
Antiinflamatorios/farmacología , Mitocondrias/metabolismo , Verbesina/química , Humanos , Estructura Molecular
5.
Planta Med ; 79(8): 707-10, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23670623

RESUMEN

Several health benefits have been attributed to members of the Verbesina genus, including promotion of urinary and gastrointestinal health. Verbesina species are also reported to exhibit antibacterial, antiparasitic, and antioxidant activities. Although members of the Verbesina genus produce various pharmacologically relevant chemicals as secondary metabolites, including eudesmanes, flavonoids, guanidine alkaloids, acetylenic compounds, and germacrenes, the active compounds required for these benefits remain unknown. To investigate potential antimicrobial activities of Verbesina negrensis, crude extracts from plant aerial structures were evaluated. Following chemical fractionation, the chloroformic extract from Verbesina negrensis was subjected to bioassay-guided isolation using disk diffusion assays to determine antimicrobial activity. The active compound was characterized as 6ß-cinnamoyloxy-1ß-hydroxy-10α-metoxy-3-oxo-germacra-4,5Z-ene (1). Fractions containing 1 inhibited both Enterococcus faecalis (ATCC 29 212) and Staphylococcus aureus (ATCC 29213). The MIC for 1 was determined by microbroth dilution assay to be 64 µg/mL for both E. faecalis and S. aureus.


Asunto(s)
Antibacterianos/aislamiento & purificación , Sesquiterpenos de Germacrano/aislamiento & purificación , Verbesina/química , Antibacterianos/química , Antibacterianos/farmacología , Enterococcus faecalis/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Pruebas de Sensibilidad Microbiana , Sesquiterpenos de Germacrano/química , Sesquiterpenos de Germacrano/farmacología , Staphylococcus aureus/efectos de los fármacos
6.
Protoplasma ; 260(1): 77-87, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35441891

RESUMEN

Allelopathy has been proposed as an efficient mechanism of invasion by plant species via growth inhibition and suppression of the resident plant community. Verbesina encelioides (Cav.) Benth. & Hook. f. ex A. Gray (golden crownbeard; Asteraceae), a native of south-western USA and Mexican Plateau, is an emerging troublesome invasive weed species of north-western states of India. We investigated the allelopathic potential of the aqueous extracts prepared from the fresh foliage and leaf litter of V. encelioides on its co-occurring species, Amaranthus viridis and Senna occidentalis. Phytotoxicity bioassay showed concentration-dependent (control < 0.5% < 1% < 2% < 4% extract) inhibition of growth and photosynthetic parameters in the test plants. Both the extracts induced ~ 50% inhibition of germination compared to control at 4% concentration. The maximum synthesis effect (collective effect on seedling length and dry weight) was observed to be - 0.69 and - 0.62 in A. viridis and - 0.68 and - 0.57 in S. occidentalis for the fresh leaf and leaf litter extracts, respectively, at 4% concentration. Also, an antagonistic concentration-dependent impact was observed on the photosynthetic pigments (total chlorophyll and chlorophyll a content) and photosynthetic efficiency. The liquid chromatography-mass spectrometry assay of leaf extracts revealed the presence of 15 allelochemicals including phenolic acids, flavonoids, phytosterols, phytophenols, dicarboxylic acid, guanidine, and triterpenes. Of these, 14 compounds were present in both fresh and leaf litter materials. However, a guanidine derivative, galegine, was only found in the fresh leaf material of the plant. The findings support the novel weapon hypothesis and suggest that V. encelioides competitively excludes its neighboring plants by virtue of allelopathic interference.


Asunto(s)
Alcaloides , Asteraceae , Verbesina , Extractos Vegetales/farmacología , Extractos Vegetales/química , Clorofila A
7.
Microbiologyopen ; 10(1): e1158, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33650801

RESUMEN

The microbiome of flowers (anthosphere) is an understudied compartment of the plant microbiome. Within the flower, petals represent a heterogeneous environment for microbes in terms of resources and environmental stress. Yet, little is known of drivers of structure and function of the epiphytic microbial community at the within-petal scale. We characterized the petal microbiome in two co-flowering plants that differ in the pattern of ultraviolet (UV) absorption along their petals. Bacterial communities were similar between plant hosts, with only rare phylogenetically distant species contributing to differences. The epiphyte community was highly culturable (75% of families) lending confidence in the spatially explicit isolation and characterization of bacteria. In one host, petals were heterogeneous in UV absorption along their length, and in these, there was a negative relationship between growth rate and position on the petal, as well as lower UV tolerance in strains isolated from the UV-absorbing base than from UV reflecting tip. A similar pattern was not seen in microbes isolated from a second host whose petals had uniform patterning along their length. Across strains, the variation in carbon usage and chemical tolerance followed common phylogenetic patterns. This work highlights the value of petals for spatially explicit explorations of bacteria of the anthosphere.


Asunto(s)
Bacterias/clasificación , Bacterias/crecimiento & desarrollo , Flores/microbiología , Flores/ultraestructura , Microbiota/genética , Bacterias/genética , Ecosistema , Helianthus/microbiología , Microscopía Electrónica de Rastreo , Plantas , Tolerancia a Radiación/fisiología , Rayos Ultravioleta , Verbesina/microbiología
8.
J Ethnopharmacol ; 265: 113248, 2021 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-32805356

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Verbesina macrophylla (Cass.) S.F.Blake is a medicinal plant from South America, popularly known as "asa de peixe", "asa de peixe branco", "cambará branco" or "cambará guaçu", being used by traditional communities for its healing powers in the form of teas, infusions, liqueurs and extracts, for the treatment of bacterial and fungal infections of the urinary and respiratory tracts, such as kidney problems, bronchitis, inflammation and fever. However, none of the ethnopharmacological properties has been scientifically evaluated. AIM OF THE STUDY: Based on the ethnopharmacological use of the species, this study investigated the chemical composition, and for the first time acute toxicity, hemolytic, antimicrobial, anti-inflammatory and antipyretic activities of the essential oil from leaves of V. macrophylla. MATERIAL AND METHODS: The essential oil was obtained from the leaves by hydrodistillation (HD), being characterized by gas chromatography coupled to mass spectrometry (GC-MS) and gas chromatography coupled to flame ionization detection (GC-FID). The antimicrobial activity was evaluated by the broth microdilution technique in bacteria and fungi that cause infections of the respiratory and urinary tract, and toxicological safety regarding hemolytic activity on human red blood cells (hRBCs), and acute toxicity in mice. The anti-inflammatory activity was evaluated by the model carrageenan-induced peritonitis with quantification of the levels of TNF-α and IL-1ß in the intraperitoneal fluid, and ear edema induced by croton oil. The antipyretic activity evaluated in mice with pyrexia induced by yeast. RESULTS: The extraction of essential oil by hydrodistillation (HD) showed a yield of 0.33 ±â€¯0.04%, with its composition constituted mainly by sesquiterpenes of hydrocarbons (94.00%). The essential oil demonstrated antibacterial and antifungal activity, with a low rate of hemolysis in human red blood cells (hRBCs) and no clinical signs of toxicity were observed in animals after acute treatment, which suggested that the LD50 is greater than 5000 mg/kg; p.o. The essential oil demonstrated anti-inflammatory activity reducing levels of pro-inflammatory cytokines TNF-α (38.83%, 72.42% and 73.52%) and IL-1ß (37.70%, 75.92% and 87.71%), and ear edema by 49.53%, 85.04% and 94.39% at concentrations of 4, 40 and 400 mg/kg, respectively. The antipyretic activity presented by the essential oil is statistically similar to dipyrone. CONCLUSION: The set of results obtained, validates the main activities attributed to the traditional use of Verbesina macrophylla (Cass.) S.F.Blake. These data add industrial value to the species, considering that the antimicrobial, anti-inflammatory and antipyretic activities present results similar to the drugs already used also presenting safety. The results suggest that essential oil from V. macrophylla may be used by industry for the development of drugs with natural antimicrobial, anti-inflammatory and antipyretic effect.


Asunto(s)
Aceites Volátiles/farmacología , Extractos Vegetales/farmacología , Verbesina/química , Animales , Antiinfecciosos/aislamiento & purificación , Antiinfecciosos/farmacología , Antiinflamatorios/aislamiento & purificación , Antiinflamatorios/farmacología , Antipiréticos/aislamiento & purificación , Antipiréticos/farmacología , Modelos Animales de Enfermedad , Relación Dosis-Respuesta a Droga , Eritrocitos/efectos de los fármacos , Femenino , Fiebre/tratamiento farmacológico , Hemólisis/efectos de los fármacos , Humanos , Inflamación/tratamiento farmacológico , Masculino , Ratones , Aceites Volátiles/aislamiento & purificación , Aceites Volátiles/toxicidad , Extractos Vegetales/toxicidad , Hojas de la Planta , Pruebas de Toxicidad Aguda
9.
J Nat Prod ; 72(6): 1022-7, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19485332

RESUMEN

Verbesinosides A-F (1-6), six new 15,27-cyclooleanane-type triterpenoid saponins carrying different aromatic acyl moieties on the aglycon, were isolated from the leaves and flowers of Verbesina virginica. Their structures were established by interpretation of spectroscopic data and chemical methods. The representative major saponin, verbesinoside A (1), has the structure 21-trimethoxybenzoyl 15alpha,27-cycloolean-12-en-3beta,21beta-diol-28-oic acid 3-O-beta-D-xylopyranosyl(1-->4)-beta-D-xylopyranosyl(1-->2)-beta-D-glucopyranoside. This is the first report of triterpenoid saponins possessing the unique 15,27-cyclooleanane skeleton. The anisotropic effects of the aromatic acyl moieties on the triterpenoid skeleton are discussed.


Asunto(s)
Ácido Oleanólico/aislamiento & purificación , Saponinas/aislamiento & purificación , Verbesina/química , Flores/química , Missouri , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/química , Hojas de la Planta/química , Saponinas/química
10.
Plant Biol (Stuttg) ; 20(3): 433-443, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29394523

RESUMEN

Secretory structures are common in Asteraceae, where they exhibit a high degree of morphological diversity. The species Verbesina macrophylla, popularly known as assa-peixe, is native to Brazil where it is widely used for medicinal purposes. Despite its potential medical importance, there have been no studies of the anatomy of this species, especially its secretory structures and secreted compounds. This study examined leaves of V. macrophylla with emphasis on secretory structures and secreted secondary metabolites. Development of secretory ducts and the mechanism of secretion production are described for V. macrophylla using ultrastructure, yield and chemical composition of its essential oils. Verbesina macrophylla has a hypostomatic leaf blade with dorsiventral mesophyll and secretory ducts associated with vascular bundles of schizogenous origin. Histochemistry identified the presence of lipids, terpenes, alkaloids and mucopolysaccharides. Ultrastructure suggests that the secretion released into the duct lumen is produced in plastids of transfer cells, parenchymal sheath cells and stored in vacuoles in these cells and duct epithelial cells. The essential oil content was 0.8%, and its major components were germacrene D, germacrene D-4-ol, ß-caryophyllene, bicyclogermacrene and α-cadinol. Secretory ducts of V. macrophylla are squizogenous. Substances identified in tissues suggest that both secretions stored in the ducts and in adjacent parenchyma cells are involved in chemical defence. The essential oil is rich in sesquiterpenes, with germacrene D and its derivatives being notable components.


Asunto(s)
Aceites Volátiles/metabolismo , Hojas de la Planta/anatomía & histología , Verbesina/anatomía & histología , Células del Mesófilo/citología , Células del Mesófilo/metabolismo , Hojas de la Planta/citología , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Sesquiterpenos Policíclicos , Sesquiterpenos/metabolismo , Sesquiterpenos de Germacrano/metabolismo , Terpenos/metabolismo , Verbesina/metabolismo , Verbesina/ultraestructura
11.
J Egypt Soc Parasitol ; 47(1): 47-54, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30157332

RESUMEN

Scanning electron microscopy (SEM) was used to study the morphological alteration occurring in Habronema muscae adult female worms after in vitro exposure to different doses of Verbesina alternifolia oil extract. The half maximal lethal concentration (LC50) was reached 400 ppm after 24hrs, while LC100 was reached 600 ppm after 48hrs. Irreversible degenerative changes were recorded such as shrinking, detachment and distortion of the cuticle, cephalic and distal region. The cuticular surface had a wrinkled, corrugated appearance with longitudinal ridges and transverse thick folds. The lips and papillae were deformed and aggregated over each other. There is a direct relation between the level of the recorded degenerative changes and the increase in the dose and exposure time. In the same time no degen'erative changes were recorded in the control worm exposed to PBS till the end of the exposure period.


Asunto(s)
Equidae/parasitología , Extractos Vegetales/farmacología , Infecciones por Spirurida/veterinaria , Spiruroidea/efectos de los fármacos , Verbesina/química , Animales , Egipto , Femenino , Enfermedades de los Caballos/tratamiento farmacológico , Enfermedades de los Caballos/parasitología , Caballos , Dosificación Letal Mediana , Microscopía Electrónica de Rastreo , Extractos Vegetales/uso terapéutico , Infecciones por Spirurida/tratamiento farmacológico , Infecciones por Spirurida/parasitología , Spiruroidea/ultraestructura
12.
Nat Prod Res ; 31(6): 676-680, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27154232

RESUMEN

The bioactive petroleum ether fraction of Verbesina encelioides, previously studied by the authors, was chosen for the isolation of antiprotozoal metabolites. Pseudotaraxasterol-3ß-acetate (1), benzyl 2,6-dimethoxy benzoate (2), 16ß-hydroxy-pseudotaraxasterol-3ß-palmitate (3) and pseudotaraxasterol (4), in addition to ß-sitosterol glucoside (5) and ß-sitosterol galactoside (6) were isolated and identified based on one-dimensional and two-dimensional spectral analysis. This is the first report describing (3) and (6) in genus Verbesina. The isolated compounds were tested in vitro against Plasmodium falciparum, Trypanosoma brucei, Trypanosoma cruzi and Leishmania infantum. Cytotoxicity was evaluated on MRC-5 cells. Compound 1 showed moderate to weak activity against L. infantum T. brucei and P. falciparum and was inactive against T. cruzi. Compound 3 showed moderate activity against L. infantum, compound 4 revealed weak activity against T. cruzi, while 5 and 6 were inactive against all tested protozoa. All compounds were non-cytotoxic. The isolated constituents showed less antiprotozoal activity than the crude fraction.


Asunto(s)
Antiprotozoarios/farmacología , Extractos Vegetales/química , Extractos Vegetales/farmacología , Verbesina/química , Animales , Antimaláricos/farmacología , Línea Celular , Fibroblastos/efectos de los fármacos , Humanos , Leishmania infantum/efectos de los fármacos , Espectroscopía de Resonancia Magnética , Plasmodium falciparum/efectos de los fármacos , Tripanocidas/farmacología , Trypanosoma brucei brucei/efectos de los fármacos , Trypanosoma cruzi/efectos de los fármacos
13.
Environ Pollut ; 143(3): 427-34, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16460853

RESUMEN

Cutleaf coneflower (Rudbeckia laciniata L.), crown-beard (Verbesina occidentalis Walt.), and tall milkweed (Asclepias exaltata L.) are wildflower species native to Great Smoky Mountains National Park (U.S.A.). Natural populations of each species were analyzed for leaf ascorbic acid (AA) and dehydroascorbic acid (DHA) to assess the role of ascorbate in protecting the plants from ozone stress. Tall milkweed contained greater quantities of AA (7-10 micromol g(-1) fresh weight) than crown-beard (2-4 micromol g(-1) fresh weight) or cutleaf coneflower (0.5-2 micromol g(-1) fresh weight). DHA was elevated in crown-beard and cutleaf coneflower relative to tall milkweed suggesting a diminished capacity for converting DHA into AA. Tall milkweed accumulated AA in the leaf apoplast (30-100 nmol g(-1) fresh weight) with individuals expressing ozone foliar injury symptoms late in the season having less apoplast AA. In contrast, AA was not present in the leaf apoplast of either crown-beard or cutleaf coneflower. Unidentified antioxidant compounds were present in the leaf apoplast of all three species. Overall, distinct differences in antioxidant metabolism were found in the wildflower species that corresponded with differences in ozone sensitivity.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Asclepias/metabolismo , Ácido Ascórbico/metabolismo , Asteraceae/metabolismo , Ozono/toxicidad , Inglaterra , Monitoreo del Ambiente , Humanos , Hojas de la Planta/metabolismo , Rudbeckia/metabolismo , Estaciones del Año , Verbesina/metabolismo
15.
Nat Prod Commun ; 10(7): 1309-10, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26411037

RESUMEN

The composition and antimicrobial activity of the essential oil from Verbesina negrensis Steyerm. leaves is reported. Analysis was performed by GC/MS. Major constituents were α-pinene (43.1%), α-humulene (13.8%), Δ-cadinene (8.1%), limonene (4.6%) and bicyclogermacrene (4.2%). The essential oil showed in vitro activity against the Gram-positive bacteria Staphylococcus aureus ATCC 25923 and Enterococcus faecalis ATCC 29212 (MIC 500 and 350 µL/mL respectively).


Asunto(s)
Antibacterianos/análisis , Aceites Volátiles/química , Verbesina/química , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Venezuela
16.
Curr Med Chem ; 10(18): 1845-62, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12871108

RESUMEN

The number and the pharmacological activities of drugs featuring a guanidine group is actually amazing. Many synthetic guanidine derivatives have attracted pharmacologists in search of new antihypertensive drugs for their ability to block adrenergic nerve activity through central and/or peripheral mechanisms. As a result, compounds such as guanethidine, guanabenz, guanfacine, and pinacidil have been introduced in antihypertensive drug therapy. A crude methanol extract of the Venezuelan plant Verbesina caracasana Fries (Compositae), intravenously administered to mice, was found to induce biological effects such as erection of hair, initial stimulation and subsequent blockade of breathing. Biologically controlled purification yielded a series of active guanidine derivatives, namely G1-G7, which were extensively studied with the focus on the following items: (1) The structure determination of the active compounds by spectral data and a set of reactions; (2) The confirmation of the structures by a biogenetically oriented synthesis; (3) The study of the pharmacological profiles of the isolated drugs; (4) The synthesis of analogous and homologous products in the effort to shed some light on the structure-activity relationship. The metabolites of V. caracasana were characterized, in anesthetized rats, as hypotensive drugs of high (G2), mild (G1, G7) and low (G3,G5,G6) potency, devoid of consistent actions in heart rate, and provided with moderate stimulatory effects on cardiac inotropism and breathing (at selected non-toxic intravenous doses). Autonomic neurogenic components and/or peripheral adrenergic and cholinergic receptor-related pathways were involved in the cardiovascular effects. Synthetic analogs and homologs of G1 and G5 were all shown to be hypotensive drugs of low-mild potency, not affecting appreciably cardiac inotropism and/or breathing. The pharmacodynamic differences among the studied compounds were likely to depend on their ability to cross the blood-brain barrier, lipophilicity and pharmacokinetics. Since most of the compounds did not induce reflex tachycardia and depression of myocardial contractility as the majority of the antihypertensive drugs, they might be useful in the treatment of arterial hypertension of various genesis.


Asunto(s)
Antihipertensivos , Verbesina/química , Animales , Antihipertensivos/síntesis química , Antihipertensivos/química , Antihipertensivos/farmacología , Factores Biológicos , Presión Sanguínea/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Guanidinas/síntesis química , Guanidinas/química , Guanidinas/farmacología , Frecuencia Cardíaca/efectos de los fármacos , Hidrólisis , Masculino , Ratones , Estructura Molecular , Ratas , Respiración/efectos de los fármacos , Estereoisomerismo
17.
Environ Pollut ; 125(1): 53-9, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12804827

RESUMEN

Incidence and severity of visible foliar ozone injury on cutleaf coneflower (Rudbeckia laciniata L.) and crown-beard (Verbesina occidentalis Walt.) were determined along selected trails at three locations in Great Smoky Mountains National Park during the summers of 2000 and 2001: Clingmans Dome, Cherokee Orchard Road and Purchase Knob. Cutleaf coneflower exhibited a greater amount of foliar injury than crown-beard each year of the 2-year study. Incidence and severity of injury was significantly greater for cutleaf coneflower growing near the edge of the Clingmans Dome trail than in the interior of the stand. Injury was greater at Clingmans Dome than Purchase Knob (70% vs. 40% ozone-injured plants, respectively), coincident with greater ozone exposures. In contrast to Clingmans Dome, there were no differences in injury between plants growing near- and off-trail at Purchase Knob. Differences in sensitivity to ozone were not observed for crown-beard growing near the edge compared with the interior of the stand adjacent to the Cherokee Orchard Road Loop. Ozone injury was greatest on the lower leaves for both species sampled with over 95% of the injured leaves occurring on the lower 50% of the plant. This is the first report of foliar ozone injury on these plant species in situ, in the Park, illustrating the great variability in symptom expression with time, and within and between populations.


Asunto(s)
Contaminantes Atmosféricos/efectos adversos , Ozono/efectos adversos , Rudbeckia/efectos de los fármacos , Verbesina/efectos de los fármacos , Monitoreo del Ambiente/métodos , Hojas de la Planta/efectos de los fármacos , Tennessee
18.
Pharmazie ; 58(5): 337-9, 2003 May.
Artículo en Inglés | MEDLINE | ID: mdl-12779051

RESUMEN

Structure-activity relationship of cinnamic acid derivatives as inhibitors of the human neutrophil elastase is reported. Comparison of the inhibitory concentrations (IC50 values) with the results of the ligand docking calculations revealed that the structure element of the aromatic ortho-dihydroxy groups combined with a lipophilic residue seems to be a prerequisite for an optimal binding within the active site.


Asunto(s)
Cinamatos/farmacología , Inhibidores Enzimáticos/farmacología , Elastasa de Leucocito/antagonistas & inhibidores , Cimicifuga/química , Cinamatos/síntesis química , Cristalografía por Rayos X , Inhibidores Enzimáticos/síntesis química , Humanos , Indicadores y Reactivos , Ligandos , Relación Estructura-Actividad , Verbesina/química
19.
Bol. latinoam. Caribe plantas med. aromát ; 18(2): 144-154, mar. 2019. tab, ilus, mapas
Artículo en Español | LILACS | ID: biblio-1007807

RESUMEN

The community of San Martin de las Flores, Jalisco, México has a varied flora, part of which is used by its residents to treat their diseases. One of these wild species that grows in this community is Verbesina sphaerocephala A.Gray (Asteraceae). The objective of this research was to provide an overview of local knowledge about the traditional uses of this plant. A quantitative ethnobotanical method to analyse the value of traditional use of this species among the community, as well as, bibliographic information on the existing phytochemical and pharmacological properties of species of the genus Verbesina has been used. When examining the general knowledge of V. sphaerocephala among the community, it was concluded that the plant is used mainly in traditional medicine to treat eight different types of diseases, highlighting its use as a wound healing and anti-inflammatory.


La comunidad de San Martin de las Flores, Jalisco, posee una variedad de flora, la cual, gran parte de ella es utilizada por sus pobladores para el tratamiento de enfermedades. Una de estas especies silvestres que crece en esta comunidad es Verbesina sphaerocephala A. Gray (Asteraceae). El objetivo de esta investigación fue proporcionar una visión general del conocimiento local sobre los usos tradicionales de esta planta. Se ha utilizado un método etnobotánico cuantitativo para analizar el valor de uso tradicional de esta especie entre la comunidad, así como también se recopiló información bibliográfica sobre las propiedades fitoquímicas y farmacológicas existentes sobre especies del género Verbesina. Al examinar el conocimiento general de V. sphaerocephala entre la comunidad, se concluyó que la planta es utilizada fundamentalmente en medicina tradicional para tratar ocho diferentes tipos de enfermedades, destacándose su uso como cicatrizante y antiinflamatorio.


Asunto(s)
Humanos , Extractos Vegetales/química , Etnobotánica , Verbesina/química , Extractos Vegetales/farmacología , Encuestas y Cuestionarios , México
20.
Curr Pharm Des ; 20(2): 253-61, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-23701541

RESUMEN

4ß-cinnamoyloxy,1ß,3α-dihydroxyeudesm-7,8-ene (CDE) extracted from Verbesina persicifolia induces bioenergetic collapse in rat liver mitochondria (RLM), monitored as a fall in the respiratory control index and ADP/O values. This fall in energy is accompanied by a protonophore effect and membrane potential (Δψ) collapse, demonstrating that CDE behaves as a typical uncoupling agent. However, when examining the effect of CDE in detail, we found that it acts as a "mild" uncoupler because it drops Δψ and increases respiratory state 4. The proposed mechanism is based on the interaction of CDE with membrane protein cytochrome C oxidase, which is implicated in proton permeability, and with the respiratory chain for the generation of reactive oxygen species which mediate and regulate the activity of the above membrane protein. Considering the energy collapse, "mild" uncoupling, and the fact that CDE is largely used in folk medicines, this extract may be viewed as a potentially effective anti-obesity drug and a natural lead compound for developing new natural uncouplers against obesity.


Asunto(s)
Fármacos Antiobesidad/farmacología , Mitocondrias Hepáticas/efectos de los fármacos , Sesquiterpenos de Eudesmano/farmacología , Verbesina/química , Animales , Fármacos Antiobesidad/aislamiento & purificación , Transporte de Electrón/efectos de los fármacos , Complejo IV de Transporte de Electrones/metabolismo , Potenciales de la Membrana/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Sesquiterpenos de Eudesmano/aislamiento & purificación , Desacopladores/aislamiento & purificación , Desacopladores/farmacología
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