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1.
Gene Ther ; 31(3-4): 105-118, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37752346

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects motor neurons, causing progressive muscle weakness and respiratory failure. The presence of an expanded hexanucleotide repeat in chromosome 9 open reading frame 72 (C9ORF72) is the most frequent mutation causing familial ALS and frontotemporal dementia (FTD). To determine if suppressing expression of C9ORF72 gene products can reduce toxicity, we designed a set of artificial microRNAs (amiRNA) targeting the human C9ORF72 gene. Here we report that an AAV9-mediated amiRNA significantly suppresses expression of the C9ORF72 mRNA, protein, and toxic dipeptide repeat proteins generated by the expanded repeat in the brain and spinal cord of C9ORF72 transgenic mice.


Asunto(s)
Esclerosis Amiotrófica Lateral , MicroARNs , Enfermedades Neurodegenerativas , Animales , Humanos , Ratones , Esclerosis Amiotrófica Lateral/genética , Esclerosis Amiotrófica Lateral/terapia , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Dipéptidos/genética , Dipéptidos/metabolismo , Expansión de las Repeticiones de ADN/genética , Ratones Transgénicos , MicroARNs/genética , Proteínas/genética , Proteínas/metabolismo
2.
Chem Biodivers ; 20(4): e202300021, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36943774

RESUMEN

Chemical investigation of the extract of the macroscopic fungus Beenakia informis led to the isolation of a previously unreported γ-pyrone and two new isoprenylated cyclohexanoids, together with speciocin N. Their structures were elucidated spectroscopically and the absolute configuration was determined by comparison of the experimental vs. calculated ECD curves. Three of the compounds showed very good to moderate activity against phytopathogenic fungi.


Asunto(s)
Antifúngicos , Basidiomycota , Antifúngicos/farmacología , Antifúngicos/química , Pironas/química , Estructura Molecular , Hongos
3.
Int J Mol Sci ; 24(18)2023 Sep 19.
Artículo en Inglés | MEDLINE | ID: mdl-37762579

RESUMEN

Oxidative stress-mediated damage is often a downstream result of Parkinson's disease (PD), which is marked by sharp decline in dopaminergic neurons within the nigrostriatal regions of the brain, accounting for the symptomatic motor deficits in patients. Regulating the level of oxidative stress may present a beneficial approach in preventing PD pathology. Here, we assessed the efficacy of a nicotinamide adenine phosphate (NADPH) oxidase (NOX) inhibitor, an exogenous reactive oxygen species (ROS) regulator synthesized by Aptabio therapeutics with the specificity to NOX-1, 2 and 4. Utilizing N27 rat dopaminergic cells and C57Bl/6 mice, we confirmed that the exposures of alpha-synuclein preformed fibrils (PFF) induced protein aggregation, a hallmark in PD pathology. In vitro assessment of the novel compound revealed an increase in cell viability and decreases in cytotoxicity, ROS, and protein aggregation (Thioflavin-T stain) against PFF exposure at the optimal concentration of 10 nM. Concomitantly, the oral treatment alleviated motor-deficits in behavioral tests, such as hindlimb clasping, rotarod, pole, nesting and grooming test, via reducing protein aggregation, based on rescued dopaminergic neuronal loss. The suppression of NOX-1, 2 and 4 within the striatum and ventral midbrain regions including Substantia Nigra compacta (SNc) contributed to neuroprotective/recovery effects, making it a potential therapeutic option for PD.


Asunto(s)
Enfermedad de Parkinson , Humanos , Ratones , Ratas , Animales , Enfermedad de Parkinson/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Agregado de Proteínas , alfa-Sinucleína/metabolismo , Encéfalo/metabolismo , Porción Compacta de la Sustancia Negra/metabolismo , Neuronas Dopaminérgicas/metabolismo , Modelos Animales de Enfermedad , Ratones Endogámicos C57BL
4.
Int J Mol Sci ; 23(8)2022 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-35457082

RESUMEN

Parkinson's disease (PD) is a progressive neurodegenerative motor disorder without an available therapeutic to halt the formation of Lewy bodies for preventing dopaminergic neuronal loss in the nigrostriatal pathway. Since oxidative-stress-mediated damage has been commonly reported as one of the main pathological mechanisms in PD, we assessed the efficacy of a novel NOX inhibitor from AptaBio Therapeutics (C-6) in dopaminergic cells and PD mouse models. The compound reduced the cytotoxicity and enhanced the cell viability at various concentrations against MPP+ and α-synuclein preformed fibrils (PFFs). Further, the levels of ROS and protein aggregation were significantly reduced at the optimal concentration (1 µM). Using two different mouse models, we gavaged C-6 at two different doses to the PD sign-displaying transgenic mice for 2 weeks and stereotaxically PFF-injected mice for 5 weeks. Our results demonstrated that both C-6-treated mouse models showed alleviated motor deficits in pole test, hindlimb clasping, crossbeam, rotarod, grooming, and nesting analyses. We also confirmed that the compound treatment reduced the levels of protein aggregation, along with phosphorylated-α-synuclein, in the striatum and ventral midbrain and further dopaminergic neuronal loss. Taken together, our results strongly suggest that NOX inhibition can be a potential therapeutic target for PD.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Animales , Modelos Animales de Enfermedad , Dopamina/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ratones , Ratones Transgénicos , Degeneración Nerviosa/patología , Enfermedad de Parkinson/metabolismo , Agregado de Proteínas , alfa-Sinucleína/metabolismo
5.
Phytochem Anal ; 31(5): 606-615, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32045084

RESUMEN

INTRODUCTION: An efficient characterisation of metabolites is a crucial task in many aspects of basic research, such as the de-replication of crude extracts in natural products chemistry or the tentative identification of compounds in untargeted metabolomics. OBJECTIVE: The goal of this work is the evaluation of the reaction with phenylhydrazine for the derivatisation post-column in situ of carbonyl-containing compounds in liquid chromatography-mass spectrometry (LC-MS). MATERIALS AND METHODS: LC-MS was performed using electrospray, Atmospheric Pressure Chemical Ionisation (APCI) or Atmospheric Pressure Photoionization (APPI) as ionisation techniques. The post-column addition of phenylhydrazine was done through a syringe pump via a T-junction before entrance to the ion source. RESULTS: A variety of natural products having carbonyl groups, such as cycloartanes, steroids, cardenolides and other terpenoids, were analysed by this method. In the case of compounds with non-hindered aldehyde or keto groups, the main signals of the mass spectra were those corresponding to the phenylhydrazones. However, the spectra of compounds with hindered carbonyl groups displayed mainly those signals corresponding to the product of the nucleophilic addition adduct of phenylhydrazine to the carbonyl, which is the first step of the derivatisation process. Finally, those compounds with conjugated ketones did not react with phenylhydrazine. This methodology was applied in the analysis of crude natural extracts. CONCLUSION: The results show that in situ derivatisation of carbonyl compounds in the ionisation source was achieved, yielding the typical derivatives of carbonyl compounds with phenylhydrazine.


Asunto(s)
Productos Biológicos , Espectrometría de Masas en Tándem , Presión Atmosférica , Cromatografía Liquida , Metabolómica , Espectrometría de Masa por Ionización de Electrospray
6.
Chem Biodivers ; 15(8): e1800133, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29851264

RESUMEN

Secondary metabolites from the cultures of the dark septate fungal endophyte (DSE) Drechslera sp., isolated from the roots of rye grass (Lollium sp.) and cultured under different experimental conditions, are described here for the first time. The use of suberoylanilidehydroxamic acid (SAHA) and other histone deacetylase inhibitors as epigenetic modifiers in the culture medium was evaluated by LC/MS and LC/MS/MS. Several differences in the metabolite production were detected by means of supervised principal component analysis (PCA) of LC/MS data. The presence of the compounds in the culture medium or in the mycelium was compared. In order to confirm their structure, many of these natural products were isolated from a larger scale culture. These metabolites were characterized as prenylhydroxybenzoic acids and chromans, two compounds, one of each class were previously undescribed, prenylquinoids, diketopiperazines and macrosphelides. Some of the compounds, which were released to the medium, showed good antifungal activity, suggesting that these compounds could protect Lollium from fungal phytopatogens. The use of SAHA as an additive of the cultures also induced the release of hexosylphytosphyngosine to the culture medium. The biotransformation of the inhibitors was observed in addition to the production of antifungal metabolites, showing the ability of this endophytic strain to control xenobiotics.


Asunto(s)
Antifúngicos/farmacología , Ascomicetos/efectos de los fármacos , Endófitos/química , Inhibidores de Histona Desacetilasas/farmacología , Histona Desacetilasas/metabolismo , Análisis de Componente Principal , Antifúngicos/química , Antifúngicos/aislamiento & purificación , Cromatografía Liquida , Endófitos/metabolismo , Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/aislamiento & purificación , Pruebas de Sensibilidad Microbiana , Espectrometría de Masas en Tándem
7.
Ann Neurol ; 79(4): 687-700, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26891182

RESUMEN

OBJECTIVE: Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by loss of motor neurons, resulting in progressive muscle weakness, paralysis, and death within 5 years of diagnosis. About 10% of cases are inherited, of which 20% are due to mutations in the superoxide dismutase 1 (SOD1) gene. Riluzole, the only US Food and Drug Administration-approved ALS drug, prolongs survival by only a few months. Experiments in transgenic ALS mouse models have shown decreasing levels of mutant SOD1 protein as a potential therapeutic approach. We sought to develop an efficient adeno-associated virus (AAV)-mediated RNAi gene therapy for ALS. METHODS: A single-stranded AAV9 vector encoding an artificial microRNA against human SOD1 was injected into the cerebral lateral ventricles of neonatal SOD1(G93A) mice, and impact on disease progression and survival was assessed. RESULTS: This therapy extended median survival by 50% and delayed hindlimb paralysis, with animals remaining ambulatory until the humane endpoint, which was due to rapid body weight loss. AAV9-treated SOD1(G93A) mice showed reduction of mutant human SOD1 mRNA levels in upper and lower motor neurons and significant improvements in multiple parameters including the numbers of spinal motor neurons, diameter of ventral root axons, and extent of neuroinflammation in the SOD1(G93A) spinal cord. Mice also showed previously unexplored changes in pulmonary function, with AAV9-treated SOD1(G93A) mice displaying a phenotype reminiscent of patient pathophysiology. INTERPRETATION: These studies clearly demonstrate that an AAV9-delivered SOD1-specific artificial microRNA is an effective and translatable therapeutic approach for ALS.


Asunto(s)
Esclerosis Amiotrófica Lateral/terapia , Dependovirus , Terapia Genética/métodos , Vectores Genéticos , MicroARNs/uso terapéutico , Superóxido Dismutasa/uso terapéutico , Animales , Animales Recién Nacidos , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Inyecciones Intraventriculares , Ventrículos Laterales , Ratones , Ratones Transgénicos , Superóxido Dismutasa-1
8.
Rapid Commun Mass Spectrom ; 28(5): 465-70, 2014 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-24497284

RESUMEN

RATIONALE: Cyclosporin A (CsA) rearranges to its isomer isocyclosporin A (isoCsA) upon acid hydrolysis and also during ionization in the ion source of the mass spectrometer. It has been reported that both compounds could not be differentiated by tandem mass spectrometry (MS/MS) using atmospheric pressure ionization (API) sources and ambiguously differentiated by using other sources. In order to analyze these compounds which are common fungal metabolites, it is relevant to develop a simple method for their differentiation. METHODS: CsA and isoCsA were analyzed by liquid chromatography/mass spectrometry (LC/MS) with post-column addition of metal ion solutions in a quadrupole time-of-flight instrument equipped with an electrospray ionization (ESI) source. RESULTS: Mass spectra of CsA obtained upon post-column addition of solutions of Ca(II), Cu(II) and Zn(II) showed complexes between cyclosporin and the metal, including [2CsA + Me](2+) and [CsA-H + Me](+). These complexes were not observed in the spectra of isoCsA. The same results were observed at different metal concentrations. CONCLUSIONS: Differentiation via metal complexation in positive ion mode LC/ESI-MS was performed to simultaneously distinguish CsA and its isomer isoCsA.


Asunto(s)
Cromatografía Liquida/métodos , Cobre/química , Ciclosporina/aislamiento & purificación , Ciclosporinas/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Zinc/química , Calcio/química , Ciclosporina/análisis , Ciclosporina/química , Ciclosporinas/análisis , Ciclosporinas/química , Espectrometría de Masas en Tándem
9.
J Phys Chem A ; 118(27): 4942-54, 2014 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-24963704

RESUMEN

Doubly charged microhydrated adducts formed from catechol and calcium(II) were produced in the gas phase using electrospray ionization (ESI) appearing as the most important ions in the mass spectra recorded. The gas phase structures of [Ca(catechol)2(H2O)](2+) and [Ca(catechol)2(H2O)2](2+) have been assayed by IR multiphoton dissociation (IRMPD) spectroscopy, recording their vibrational spectra in the 3450-3750 cm(-1) range (OH stretching region) and in the 900-1700 cm(-1) fingerprint spectral region. The agreement between experimental and calculated IR spectra of the selected cluster ions confirmed the suitability of the proposed geometries. In addition, quantum chemical calculations at the B3LYP/6-311+G(d,p) level of theory were performed for [Ca(catechol)2(H2O)](2+) to gain insight into the major routes of dissociation. The results suggest that loss of the water molecule is the lowest energy fragmentation channel followed by charge separation products and neutral loss of one catechol molecule, in agreement with the product ions observed upon collision-induced dissociation (CID).

10.
Mar Drugs ; 12(12): 5864-80, 2014 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-25486111

RESUMEN

Five new polyoxygenated marine steroids-punicinols A-E (1-5)-were isolated from the gorgonian Leptogorgia punicea and characterized by spectroscopic methods (IR, MS, 1H, 13C and 2-D NMR). The five compounds induced in vitro cytotoxic effects against lung cancer A549 cells, while punicinols A and B were the most active, with IC50 values of 9.7 µM and 9.6 µM, respectively. The synergistic effects of these compounds with paclitaxel, as well as their effects on cell cycle distribution and their performance in the clonogenic assay, were also evaluated. Both compounds demonstrated significant synergistic effects with paclitaxel.


Asunto(s)
Antozoos/química , Esteroides/química , Esteroides/farmacología , Animales , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Sinergismo Farmacológico , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Espectroscopía de Resonancia Magnética/métodos , Paclitaxel/farmacología
11.
Metallomics ; 16(2)2024 02 07.
Artículo en Inglés | MEDLINE | ID: mdl-38337175

RESUMEN

Steroids that take part in the pathways of human steroidogenesis are involved in many biological mechanisms where they interact with calcium. In the present work, the binding selectivities and affinities for calcium of progestagens, mineralocorticoids, androstagens, and estrogens were studied by Electrospray Ionization-Mass Spectrometry (ESI-MS). The adduct profile of each steroid was characterized by high resolution and tandem mass spectrometry. The relative stability of the most important adducts was studied by threshold collision induced dissociation, E1/2. Doubly-charged steroid-calcium complexes [nM + Ca]2+ with n = 1-6 were predominant in the mass spectra. The adduct [5M + Ca]2+ was the base peak for most 3-keto-steroids, while ligands bearing hindered ketones or α-hydroxy-ketones also yielded [nM + Ca + mH2O]2+ with n = 3-4 and m = 0-1. Principal component analysis allowed us to spot the main differences and similarities in the binding behavior of these steroids. The isomers testosterone and dehydroepiandrosterone, androstanolone and epiandrosterone, and 17-α-hydroxyprogesterone and 11-deoxycorticosterone showed remarkable differences in their adduct profiles. Computational modeling of representative adducts was performed by density functional theory methods. The possible binding modes at low and high numbers of steroid ligands were determined by calcium Gas Phase Affinity, and through modeling of the complexes and comparison of their relative stabilities, in agreement with the experimental results.


Asunto(s)
Calcio , Espectrometría de Masa por Ionización de Electrospray , Humanos , Calcio/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Espectrometría de Masas en Tándem/métodos , Esteroides , Cetonas
12.
Environ Sci Pollut Res Int ; 31(24): 35308-35319, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38727975

RESUMEN

Daphnia spinulata Birabén, 1917 is an endemic cladoceran species, frequent in the zooplankton communities of the shallow lakes of the Pampean region of Argentina. These lakes have varying salinity levels and, being located in agricultural areas, are frequently subject to pesticide pollution. This study aimed to determine the effects of the herbicide glyphosate (Panzer Gold®) in combination with different salinity levels on the biological parameters of D. spinulata and its recovery ability after a short exposure. Three types of assays were performed: an acute toxicity test, a chronic assessment to determine survival, growth and reproduction, and recovery assays under optimal salinity conditions (1 g L-1). The LC50-48 h of glyphosate was 7.5 mg L-1 (CL 3.15 to 11.72). Longevity and the number of offspring and clutches were significantly reduced due to the combined exposure of glyphosate and increased salinity. The timing of the first offspring did not recover after glyphosate exposure. Our results reveal that D. spinulata is sensitive to the herbicide Panzer Gold® at concentrations well below those indicated in the safety data sheet of this commercial formulation, which causes stronger negative effects in conditions of higher salinity. Further research is needed to shed light on the sensitivity of this cladoceran to glyphosate and its variability under other interactive stress factors.


Asunto(s)
Daphnia , Glicina , Glifosato , Herbicidas , Salinidad , Animales , Glicina/análogos & derivados , Glicina/toxicidad , Daphnia/efectos de los fármacos , Herbicidas/toxicidad , Contaminantes Químicos del Agua/toxicidad , Argentina , Reproducción/efectos de los fármacos
13.
Foods ; 13(7)2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38611283

RESUMEN

The total phenolic, flavonoid, and anthocyanin contents were evaluated in 11 cultivars of Argentinian roses of different colors. HPLC-ESI-QTOF/MS was used to identify the components where ellagic and quinic acids, quercetin, and kaempferol glycosylated derivatives were found. The phenolic contents ranged from 78.8 ± 3.2 to 203.4 ± 3.1 mg GAE/g dw, the flavonoid content ranged from 19.1 ± 3.8 to 125.9 ± 6.5 mg QE/g dw, and the anthocyanin content ranged from less than 0.01 to 5.8 ± 0.1 mg CE/g dw. The dark red cultivars exhibited the greatest levels of the analyzed compounds and of the antioxidant activities, even higher than those of certain plants known for their high phenolic contents and antioxidant activity. Moreover, the addition of these extracts decreased the population of L. innocua and P. aeruginosa to undetectable levels 24 h after inoculation. Rose petal extracts, mainly those with a dark red color, can be used as natural additives in food, feed, and cosmetics, as they contain a high proportion of bioactive compounds with antioxidant and antimicrobial effects.

14.
Planta Med ; 79(18): 1724-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24222042

RESUMEN

Five new neolignans with a bicyclo[2.2.2]octene framework were isolated from an ethanolic extract of the bark of Cordia americana. The structures and relative configurations of the compounds were elucidated by a combination of spectroscopic methods. All the isolated compounds showed good antioxidant activities in the DPPH radical scavenging (0.5-100 µg/mL) and Ferric-reducing antioxidant power (FRAP, 1-100 µg/mL) assays. One of the compounds displayed mild fungistatic activity at 0.1 µmol/spot against Fusarium virguliforme while, at the same time, all compounds were inactive against several strains of Gram (+) and Gram (-) bacteria at all assayed concentrations (10-1,000 µg/mL).


Asunto(s)
Antifúngicos/aislamiento & purificación , Antioxidantes/aislamiento & purificación , Cordia/química , Lignanos/aislamiento & purificación , Antifúngicos/química , Antifúngicos/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Bacterias/efectos de los fármacos , Compuestos Bicíclicos con Puentes , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/aislamiento & purificación , Depuradores de Radicales Libres/farmacología , Fusarium/efectos de los fármacos , Lignanos/química , Lignanos/farmacología , Medicina Tradicional , Estructura Molecular , Oxidación-Reducción , Corteza de la Planta/química , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Plantas Medicinales
15.
Mar Drugs ; 11(11): 4176-92, 2013 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-24172213

RESUMEN

The n-butanol fraction (BF) obtained from the crude extract of the marine sponge Petromica citrina, the halistanol-enriched fraction (TSH fraction), and the isolated compounds halistanol sulfate (1) and halistanol sulfate C (2), were evaluated for their inhibitory effects on the replication of the Herpes Simplex Virus type 1 (HSV-1, KOS strain) by the viral plaque number reduction assay. The TSH fraction was the most effective against HSV-1 replication (SI = 15.33), whereas compounds 1 (SI = 2.46) and 2 (SI = 1.95) were less active. The most active fraction and these compounds were also assayed to determine the viral multiplication step(s) upon which they act as well as their potential synergistic effects. The anti-HSV-1 activity detected was mediated by the inhibition of virus attachment and by the penetration into Vero cells, the virucidal effect on virus particles, and by the impairment in levels of ICP27 and gD proteins of HSV-1. In summary, these results suggest that the anti-HSV-1 activity of TSH fraction detected is possibly related to the synergic effects of compounds 1 and 2.


Asunto(s)
Antivirales/química , Antivirales/farmacología , Herpesvirus Humano 1/efectos de los fármacos , Poríferos/química , Esteroles/química , Esteroles/farmacología , 1-Butanol/química , Animales , Brasil , Línea Celular , Chlorocebus aethiops , Células Vero , Ensayo de Placa Viral/métodos
16.
Antioxidants (Basel) ; 12(3)2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36978929

RESUMEN

The effect of freeze and hot air drying methods on the retention of total phenolics, antioxidant activity (AA), and color of different cultivars of rose petals was analyzed. Both methods similarly preserved the phenolic content and AA, while freeze drying showed better red color retention. Furthermore, the conditions of total phenolics and AA extraction from two rose cultivars, Lovely Red and Malu, were optimized by response surface methodology through a Box-Behnken design. The solvent exhibited a major effect on the total phenolic content (TPC) and AA. The selected parameters were ethanol 38%, 75 °C, and 30 min. Under these conditions, the predicted values for Lovely Red were 189.3 mg GA/g dw (TPC) and 535.6 mg Trolox/g dw (AA), and those for Malu were 108.5 mg GA/g dw (TPC) and 320.7 mg Trolox/g dw (AA). The experimental values were close to the predicted values, demonstrating the suitability of the model. Ultrasound-assisted extraction increased the AA of the extracts but not the TPC. Fifteen compounds were identified in the Lovely Red cultivar, with no differences between the two drying methods. The results obtained suggest that the analyzed cultivars, particularly the red ones, can be considered a natural source of powerful antioxidant compounds.

17.
Peptides ; 159: 170900, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36336169

RESUMEN

Amphibians have a great diversity of bioactive peptides in their skin. The cDNA prepro-peptide sequencing allowed the identification of five novel mature peptides expressed in the skin of Boana pulchella, four with similar sequences to hylin peptides having a cationic amphipathic-helical structure. Whole mature peptides and some of their fragments were chemically-synthesized and tested against Gram-positive and Gram-negative bacterial strains. The mature peptide hylin-Pul3 was the most active, with a MIC= 14 µM against Staphylococcus aureus. Circular dichroism assays indicated that peptides are mostly unstructured in buffer solutions. Still, adding large unilamellar vesicles composed of dimyristoyl phosphatidylcholine and dimyristoylphosphatidylglycerol increased the α-helix content of novel hylins. These results demonstrate the strong influence of the environment on peptide conformation and highlight its significance while addressing the pharmacology of peptides and their biological function in frogs.


Asunto(s)
Anuros , Péptidos , Animales , Secuencia de Aminoácidos , Péptidos/farmacología , Péptidos/química , Lípidos , Dicroismo Circular
18.
iScience ; 26(11): 108109, 2023 Nov 17.
Artículo en Inglés | MEDLINE | ID: mdl-37867936

RESUMEN

The host-microbiome associations occurring on the skin of vertebrates significantly influence hosts' health. However, the factors mediating their interactions remain largely unknown. Herein, we used integrated technical and ecological frameworks to investigate the skin metabolites sustaining a beneficial symbiosis between tree frogs and bacteria. We characterize macrocyclic acylcarnitines as the major metabolites secreted by the frogs' skin and trace their origin to an enzymatic unbalance of carnitine palmitoyltransferases. We found that these compounds colocalize with bacteria on the skin surface and are mostly represented by members of the Pseudomonas community. We showed that Pseudomonas sp. MPFS isolated from frogs' skin can exploit acylcarnitines as its sole carbon and nitrogen source, and this metabolic capability is widespread in Pseudomonas. We summarize frogs' multiple mechanisms to filter environmental bacteria and highlight that acylcarnitines likely evolved for another function but were co-opted to provide nutritional benefits to the symbionts.

19.
Biochem Biophys Res Commun ; 427(1): 107-12, 2012 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-22982541

RESUMEN

The need to develop novel antiviral agents encouraged us to assess the antiviral activity of synthetic sterol analogues with a diamide side chains. Cytotoxicity and antiviral activity of a family of azasterol previously synthesized was evaluated against herpes simplex virus 1 (HSV-1) (KOS and B2006) and vesicular stomatitis virus (VSV). This family of compounds was extended by the synthesis of novel analogs using an Ugi multicomponent reaction and their ability to inhibit viral multiplication was also evaluated. The results show that some of the compounds tested exert an antiviral activity. Besides, the effect of the azasterols on the intracellular localization of viral glycoproteins was examined. Strikingly, alteration on the glycoprotein D (gD) of HSV-1 fluorescence pattern was observed with both the antiherpetic compounds and the inactive azasterols.


Asunto(s)
Antivirales/química , Diamida/química , Herpesvirus Humano 1/efectos de los fármacos , Esteroles/química , Proteínas del Envoltorio Viral/metabolismo , Antivirales/aislamiento & purificación , Antivirales/farmacología , Herpesvirus Humano 1/metabolismo , Humanos , Espacio Intracelular/metabolismo , Esteroles/aislamiento & purificación , Esteroles/farmacología , Replicación Viral/efectos de los fármacos
20.
Bioorg Med Chem ; 20(9): 3016-30, 2012 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-22472043

RESUMEN

Two cucurbitacins, dihydrocucurbitacin B (1) and cucurbitacin B (2), which can be obtained in large amounts from the roots of Wilbrandia ebracteata and from the fruits of Luffa operculata, respectively, were used as starting materials for the preparation of a library of 29 semi-synthetic derivatives. The structural changes that were performed include the removal, modification or permutation of functional groups in rings A and B as well as in the side chain. All new semisynthetic compounds, as well as 1 and 2, were tested in vitro for their cytotoxic effects on non-small-cell lung cancer cells (A549 cells). Some of these compound displayed potent to moderate activity against A549 tumor cells, especially those cucurbitacin B derivatives which were modified at ring A.


Asunto(s)
Antineoplásicos/síntesis química , Antineoplásicos/toxicidad , Triterpenos/química , Triterpenos/toxicidad , Antineoplásicos/química , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cucurbitaceae/química , Frutas/química , Humanos , Luffa/química , Raíces de Plantas/química , Triterpenos/síntesis química
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