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1.
Dis Aquat Organ ; 143: 159-168, 2021 Feb 25.
Artículo en Inglés | MEDLINE | ID: mdl-33632994

RESUMEN

We investigated the cause of skeletal deformities found in brown trout from the Aspromonte mountain area in Reggio Calabria, Italy. Toxicological, histopathological and parasitological analyses were carried out on 14 fish with evident macro-morphological alterations from 2 different locations in the same river, and 4 control fish without morphological alterations from a different river (far from the first river but still within the area under study). Histopathological and radiological observations confirmed severe skeletal deformities in the specimens investigated. Parasitological examinations highlighted the presence of the nematode Cystidicoloides ephemeridarum, found only within the gastrointestinal tract of specimens showing deformities. Moreover, a direct correlation between parasite number and fish size was found. Given the low heavy metal levels and the presence of a massive parasitosis in teleosts showing deformities, we postulate a correlation between skeletal deformities and nematode infestation: the parasites caused a serious vitamin and mineral deficiency in the fish, which led to a dysplastic vertebral column. The low calcium levels found in malformed specimens compared with negative controls effectively confirm this hypothesis.


Asunto(s)
Enfermedades de los Peces , Animales , Italia , Trucha
2.
Ecotoxicol Environ Saf ; 150: 96-103, 2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29268120

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) are lipophilic compounds able to accumulate in the food chain. Mussels showed to bioaccumulate contaminants, such as PAHs, so that recurrent consumption of such contaminated food represents a risk for human health. This study was aimed to elucidate if acute exposure of Mediterranean blue mussel (Mytilus galloprovincialis), a bivalve of great economic importance in several countries, to a PAH, benzo[a]pyrene (B[a]P), at doses able to induce cytochrome P450 1A (CYP1A) and pathological changes in mussel gills, can produce accumulation in soft tissue. We explored the cytotoxic effects (cell viability, DNA laddering, and glutathione levels) of in vitro exposure of human peripheral blood mononuclear cells (PBMCs) to organic extracts obtained from blue mussels previously exposed for 12 and 72h via water to B[a]P (0.5-1mg/L). In our experimental conditions, B[a]P induced CYP1A induction and morphological changes in mussel gills and a significant B[a]P accumulation in soft tissue. Conversely, exposing PBMCs to organic extracts obtained from contaminated mussels, resulted in a significant reduction of cell viability and cell glutathione content, and in an increase in DNA laddering. This confirms that consumption of mussels from B[a]P polluted waters might affect human health. Our data lead us to suggest that CYP1A activity in mussel gills may be useful (more than the amount of detected PAHs in the mussel edible tissue) as a marker in assessment of risk for health of consumers exposed to PAHs through ingestion of shellfish.


Asunto(s)
Benzo(a)pireno/toxicidad , Mytilus edulis/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Benzo(a)pireno/análisis , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Relación Dosis-Respuesta a Droga , Branquias/química , Branquias/efectos de los fármacos , Branquias/patología , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Medición de Riesgo , Contaminantes Químicos del Agua/análisis
3.
Ecotoxicol Environ Saf ; 122: 116-25, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26232038

RESUMEN

Polycyclic aromatic hydrocarbons (PAHs) can accumulate in the food chain, due to their lipophilic properties. Fish can accumulate contaminants including PAHs and frequent consumption of such contaminated fish can pose risk to human health. The aim of this study was to clarify if acute exposure of sea bream (Sparus aurata, a fish species of great economic importance in the Atlantic and Mediterranean areas) to a PAH, benzo[a]pyrene (B[a]P), at a dose that can induce CYP1A and pathological changes in fish gills, liver and muscle, can induce accumulation in muscle. We investigated the cytotoxic effects (as changes in cell viability, DNA laddering and glutathione content) of in vitro exposure of human peripheral blood mononuclear cells (PBMCs) to organic extracts obtained from muscle of sea breams previously exposed via water to B[a]P (2mg/l, for 12, 24 and 72 h). At this level of exposure, B[a]P caused morphological changes, inflammatory response and CYP1A induction not only in sea bream gills and liver but also in muscle; furthermore, in fish muscle we observed a substantial B[a]P accumulation, which may be associated with the increased CYP1A activity in liver and especially in muscle. However, when PBMCs were exposed to organic extracts obtained from sea bream muscle contaminated with B[a]P, a toxic, although modest effect was revealed, consisting in a significant decrease in cell glutathione levels without alterations in cell viability and DNA laddering. This suggests that consumption of sea breams from B[a]P contaminated waters might represent a risk for human health.


Asunto(s)
Benzo(a)pireno/toxicidad , Contaminación de Alimentos , Dorada , Contaminantes Químicos del Agua/toxicidad , Animales , Supervivencia Celular/efectos de los fármacos , Citocromo P-450 CYP1A1/metabolismo , Branquias/efectos de los fármacos , Branquias/metabolismo , Glutatión/metabolismo , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Leucocitos Mononucleares/metabolismo , Hígado/efectos de los fármacos , Hígado/metabolismo , Músculos/efectos de los fármacos , Músculos/metabolismo , Medición de Riesgo
4.
Front Pharmacol ; 12: 722398, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34594220

RESUMEN

Recently, many studies have highlighted the health effects of betalains beyond their use as food dyes. The present study investigated betalain-rich extracts with different colors and their main bioactive compounds in order to provide first evidence as a new promising strategy for intestinal inflammation management. Prickly pear betalain-rich extracts, obtained by a QuEChERS method, have been characterized by LC-DAD-ESI-MS/MS analysis. The potential role of betanin, indicaxanthin, and prickly pear extracts in counteracting the antioxidant and anti-inflammatory events was evaluated by several in vitro cell-free and cell-based assays. Indicaxanthin and betanin represent the most abundant compounds (≥22.27 ± 4.50 and 1.16 ± 0.17 g/100 g dry extract, respectively). Prickly pear extracts showed the strongest antioxidant and anti-inflammatory activities with respect to the pure betalains both on in vitro cell-free and cell-based assays, demonstrating the occurrence of synergistic activity, without any cytotoxicity or alteration of the barrier systems. The release of reactive oxygen species (ROS) and key inflammatory markers (IL-6, IL-8, and NO) was strongly inhibited by both betalains and even more by prickly pear extracts, which showed a similar and sometimes better profile than the reference compounds trolox and dexamethasone in counteracting the IL-1ß-induced intestinal inflammation.

5.
Vet Rec ; 165(1): 19-22, 2009 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-19578190

RESUMEN

The pharmacokinetics of teicoplanin were evaluated in 10 healthy sheep. After intravenous injection it showed monophasic behaviour, with a short mean (sd) elimination half-life (5 [0.24] hours). After intramuscular injection its bioavailability was 100 per cent but it was absorbed slowly; its elimination half-life was satisfactorily slow (9.23 [0.74] hours). Its efficacy was evaluated in 26 crossbreed sheep with milk positive to strains of Staphylococcus aureus, coagulase-negative staphylococci and Streptococcus agalactiae, and clinical signs of disease. In 19 of them a single intramuscular dose of 6 mg/kg bodyweight resulted in a complete resolution of the clinical signs, and no microorganisms were detected in milk by the fifth day; in the other seven sheep, with more severe intramammary infections, three consecutive daily intramuscular doses of 6 mg/kg bodyweight were necessary. There were no local or systemic side effects and no relapses during 30 days after the treatments in any of the sheep.


Asunto(s)
Antibacterianos/farmacocinética , Mastitis/veterinaria , Enfermedades de las Ovejas/tratamiento farmacológico , Teicoplanina/farmacocinética , Animales , Antibacterianos/administración & dosificación , Antibacterianos/efectos adversos , Antibacterianos/uso terapéutico , Relación Dosis-Respuesta a Droga , Vías de Administración de Medicamentos , Femenino , Inyecciones Intramusculares/veterinaria , Inyecciones Intravenosas/veterinaria , Mastitis/tratamiento farmacológico , Ovinos , Teicoplanina/administración & dosificación , Teicoplanina/efectos adversos , Teicoplanina/uso terapéutico , Resultado del Tratamiento
6.
Phytother Res ; 22(3): 313-7, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18058988

RESUMEN

Herpes simplex virus type 1 (HSV-1) and herpes simplex virus type 2 (HSV-2) are common human pathogens that in particular cases can also cause severe problems especially in immunodeficient patients. The present paper reports the antiviral and immunomodulatory properties of a methanolic extract of C. spinosa buds (CAP), rich in flavonoids, including several quercetin and kaempferol glycosides. In particular we have investigated whether the in vitro exposure of human peripheral blood mononuclear cells (PBMCs) to CAP might inhibit the replication of HSV-2 and modulate the induction kinetics of IL-12, TNF-alpha IFN-gamma. Our findings have shown that CAP treatment interferes with HSV-2 replication in PBMCs inhibiting the extracellular virus release upregulating their production of IL-12, IFN-gamma and TNF-alpha. One could speculate that CAP may contribute in improving immune surveillance of PBMCs toward virus infection by up-regulating expression of peculiar proinflammatory cytokines; it should thus be successfully employed for treatment of HSV-2 infections in immunocompromised hosts.


Asunto(s)
Antivirales/farmacología , Capparis/química , Factores Inmunológicos/farmacología , Leucocitos Mononucleares/efectos de los fármacos , Regulación hacia Arriba/efectos de los fármacos , Células Cultivadas , Citocinas/análisis , Citocinas/biosíntesis , Flores/química , Liofilización , Herpesvirus Humano 2/crecimiento & desarrollo , Leucocitos Mononucleares/inmunología , Leucocitos Mononucleares/virología , Metanol/química , Replicación Viral/efectos de los fármacos
7.
Biomed Mater Eng ; 18(3): 137-48, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18725694

RESUMEN

Ultra high molecular weight polyethylene, both pure and electron beam irradiated, was exposed to air and hyaluronic acid. Physical and mechanical analyses were performed in order to check the polymeric change due to the treatment. Pure UHMWPE, in fact, was modified by the hyaluronic acid that plasticizes the polymer. The electron irradiation cross links the chains and prevents their sliding in acid presence. A low irradiation dose is preferable rather than an high one. Low doses induce low amount of free radicals, witch react with oxygen and hyaluronic acid inducing low polymer degrade maintaining the initial mechanical performance. High doses degrade significantly the polymer properties.100 kGy irradiation in air can be applicable on the polyethylene as well as a compromise between the low mechanical performance improving and the material degradation.


Asunto(s)
Electrones , Ácido Hialurónico/efectos adversos , Polietilenos/efectos de la radiación , Aire , Fenómenos Biomecánicos , Radicales Libres/química , Ácido Hialurónico/química , Materiales Manufacturados/efectos de la radiación , Ensayo de Materiales , Polietilenos/química , Dosis de Radiación , Radiación Ionizante , Propiedades de Superficie/efectos de la radiación
8.
Oxid Med Cell Longev ; 2018: 2492063, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29643973

RESUMEN

Oxidative and electrophilic changes in cells are mainly coordinated by the KEAP1/NRF2 (Kelch-like erythroid-derived cap-n-collar homology- (ECH-) associated protein-1/nuclear factor (erythroid-derived 2)-like 2) axis. The physical interaction between these two proteins promotes the expression of several antioxidant defense genes in response to exogenous and endogenous insults. Recent studies demonstrated that KEAP1/NRF2 axis dysfunction is also strongly related to tumor progression and chemo- and radiotherapy resistance of cancer cells. In solid tumors, the KEAP1/NRF2 system is constitutively activated by the loss of KEAP1 or gain of NFE2L2 functions that leads to its nuclear accumulation and enhances the transcription of many cytoprotective genes. In addition to point mutations, epigenetic abnormalities, as aberrant promoter methylation, and microRNA (miRNA) and long noncoding RNA (lncRNA) deregulation were reported as emerging mechanisms of KEAP1/NRF2 axis modulation. This review will summarize the current knowledge about the epigenetic mechanisms that deregulate the KEAP1/NRF2 cascade in solid tumors and their potential usefulness as prognostic and predictive molecular markers.


Asunto(s)
Metilación de ADN , Proteína 1 Asociada A ECH Tipo Kelch/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , ARN no Traducido/genética , Animales , Epigénesis Genética , Humanos , Proteína 1 Asociada A ECH Tipo Kelch/genética , Factor 2 Relacionado con NF-E2/genética , Transducción de Señal
9.
Food Chem Toxicol ; 119: 112-121, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29753868

RESUMEN

Today, in many European countries, people are looking for wild edible plants to experience new tastes and flavors, by following the new trend of being green and environmentally friendly. Young borage and spinach leaves can be easily confused by inexpert pickers with those of other plants, including poisonous ones, such as Mandragora autumnalis Bertol. (mandrake) or Digitalis purpurea L. (foxglove), common in southern and northern Italy respectively. In the last twenty years, several cases of intoxication by accidental ingestion of mandrake and foxglove have been reported. The purpose of this work was to perform a pharmacognostic characterization of young leaves from borage, mandrake, foxglove and spinach, by micro-morphological, molecular and phytochemical techniques. The results showed that each of the three techniques investigated could be sufficient alone to provide useful information for the identification of poisonous species helping the medical staff to manage quickly the poisoned patients. However, the multi-disciplinary approach proposed could be very useful to asses the presence of poisonous plants in complex matrices, to build a database containing morphological, molecular and phytochemical data for the identification of poisonous species or in forensic toxicology, given their increasingly frequent use due to their low cost and relatively common availability.


Asunto(s)
Hojas de la Planta/química , Plantas Comestibles/química , Plantas Tóxicas/química , Alcaloides/química , Cromatografía de Gases , Glicósidos Digitálicos/química , Cromatografía de Gases y Espectrometría de Masas , Humanos , Italia , Región Mediterránea , Fitoquímicos , Hojas de la Planta/ultraestructura
10.
Fitoterapia ; 124: 49-57, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29050970

RESUMEN

Black carrot (Daucus carota L. ssp. sativus var. atrorubens Alef.) is a valuable source of carbohydrates, minerals and vitamins and contains also high amounts of anthocyanins giving the characteristic deep-purple color. These latter compounds are known as natural dyes used in the food and pharmaceutical industry that have recently attracted much attention for their healthful properties. The aim of this work was to investigate for the first time the polyphenolic profile and biological properties of a black carrot crude extract (BCCE) through an in-depth analysis of the main polyphenolic classes evaluating its antioxidant, cytoprotective and anti-angiogenic properties. Twenty five polyphenols were quantified by LC-DAD-FLD-MS/MS analysis (anthocyanins 78.06%, phenolic acids 17.89% and other flavonoids 4.06%) with polyglycosylated cyanidins as major components. In addition, BCCE showed a strong antioxidant and free radical scavenging activity particularly in the hydrogen transfer-based assays (ORAC and ß-carotene bleaching) and a significant increase in the cell viability. Furthermore, BCCE exhibited a strong anti-angiogenic activity at the highest concentration assayed on the chick chorioallantoic membrane (50µg/egg). In conclusion, the obtained results demonstrated the antioxidant, cytoprotective and anti-angiogenic properties of BCCE, which highlight that the higher biological activity of BCCE is probably due to the synergic effects exerted by various polyphenolic classes.


Asunto(s)
Daucus carota/química , Extractos Vegetales/química , Polifenoles/análisis , Inhibidores de la Angiogénesis/análisis , Animales , Células Cultivadas , Embrión de Pollo , Flavonoides/análisis , Depuradores de Radicales Libres/análisis , Humanos , Proantocianidinas/análisis
11.
Water Sci Technol ; 56(9): 157-65, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-18025743

RESUMEN

This paper provides new insights on the application of the ozonation process for the reduction of activated sludge production in a Sequencing Batch Reactor. The study was performed on two identical lab-scale SBRs plant, fed with domestic sewage: a fraction (1/3 of the working volume) of the activated sludge from one reactor (Exp SBR) was periodically subjected to ozonation for 30 minutes at 0.05 g O(3)/gSS and then recirculated before the beginning of the cycle; the other reactor was used as control and therefore managed at the same sludge retention time but without the application of ozonation. The effects of the recirculation of the ozonated sludge to the Exp SBR were evaluated in terms of biological nitrogen and carbon removal efficiencies, Mixed Liquor Volatile and Suspended Solids (MLSS and MLVSS, respectively) concentrations, effluent quality and sludge settleability. Besides, characterization of the ozonated sludge was carried out for different oxidant dosages (0.05, 0.07 and 0.37 g O(3)/gSS) and durations of the ozonation process (10, 20 and 30 minutes). The results show that at 0.05 g O(3)/gSS and 30 minutes contact time MLVSS as well as MLVSS/MLSS ratio do not change appreciably. Ozone dosage must be increased much further to obtain a relevant effect.


Asunto(s)
Ozono/química , Aguas del Alcantarillado/química , Eliminación de Residuos Líquidos/métodos , Reactores Biológicos , Carbono/química , Nitrógeno/química , Oxidación-Reducción , Factores de Tiempo
12.
Toxicol In Vitro ; 20(8): 1395-402, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16901675

RESUMEN

Several studies have shown that UV radiation on the skin results in the formation of reactive oxygen species (ROS) that interact with proteins, lipids and DNA, thus altering cellular functions. The epidermis is composed mainly of keratinocytes, rich in ROS detoxifying enzymes and in low-molecular-mass antioxidant molecules. However, the increased generation of ROS can overwhelm the natural defences against oxidative stress. Therefore treatment of the skin with products containing plant-derived antioxidant ingredients may be a useful strategy for the prevention of UV-mediated cutaneous damage. In the present study we have investigated the in vitro capability of a Jacquez grapes wine extract (containing a significant level of proanthocyanidins, together with lower amounts of anthocyanins and hydroxycinnamic acids; JW-E), to protect skin against UVB-induced oxidative damage by using a three-dimensional tissue culture model of human epidermis. The endpoints of our experiments were cell viability, release of interleukin-1alpha and prostaglandin E(2) (well-known mediators of cutaneous inflammatory processes), accumulation in the epidermis of malondialdehyde/4-hydroxynonenal and protein carbonyl groups (derived by the oxidative damage respectively of lipids and proteins) and tissue redox balance (expressed by the levels of reduced glutathione, oxidized glutathione, glutathione peroxidase and glutathione reductase). Taken together, our findings demonstrate that the JW-E is an efficient botanical mixture able to prevent skin oxidative damage induced by UV-B exposure and may thus be a potential promising candidate as a skin photoprotective agent.


Asunto(s)
Protectores contra Radiación/farmacología , Envejecimiento de la Piel/efectos de los fármacos , Vitis/química , Aldehídos/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Dinoprostona/metabolismo , Liofilización , Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Humanos , Interleucina-1alfa/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/uso terapéutico , Rayos Ultravioleta
13.
Environ Int ; 32(6): 705-10, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16750268

RESUMEN

The aim of this study is to assess the accumulation of OCs and PCBs in Thunnus thynnus and to elucidate the suitability of this species as a bioindicator for monitoring contaminations of these compounds in the marine ecosystems of the Straits of Messina. This investigation was conducted on fat, liver and muscle samples of 14 T. thynnus collected during April 2004. Quantitative determination of OCs and PCBs in the various samples examined has been carried out using GC-ECD and GC-MS. The results obtained show the presence of low concentrations of p,p'-DDE and PCB congeners (138, 153 and 180) in all fat, liver and muscle samples caught in the Straits of Messina. Concentrations of p,p'-DDE and PCB congeners (138, 153 and 180) in all the samples examined were below MRLs (CE n. 97/41, 1999/65 and 1999/71).


Asunto(s)
Hidrocarburos Clorados/análisis , Residuos de Plaguicidas/análisis , Atún/metabolismo , Contaminantes Químicos del Agua/análisis , Tejido Adiposo/química , Animales , Monitoreo del Ambiente , Femenino , Contaminación de Alimentos , Hidrocarburos Clorados/metabolismo , Hígado/química , Masculino , Músculos/química , Residuos de Plaguicidas/metabolismo , Alimentos Marinos , Sicilia , Contaminantes Químicos del Agua/metabolismo
14.
Nat Prod Res ; 30(24): 2845-2849, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26998559

RESUMEN

Acetaminophen (N-acetyl-p-aminophenol, APAP) overdosage can produce fatal centrilobular hepatic necrosis in humans. The present study attempted to investigate the protective effect of an anthocyanin-rich extract from bilberries and blackcurrants (AE) against APAP-induced acute hepatic damage in rats. Treatment with AE normalised blood activities of glutamate oxaloacetate and glutamate pyruvate transaminase and prevented APAP-induced plasmatic and tissutal alterations in biomarkers of oxidative stress, probably due to various bioproperties of the components of the extract.

15.
FEMS Microbiol Lett ; 198(1): 9-13, 2001 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-11325546

RESUMEN

In the present paper we report the 'in vitro' activity of eight aliphatic long-chain aldehydes from olive flavor (hexanal, nonanal, (E)-2-hexenal, (E)-2-eptenal, (E)-2-octenal, (E)-2-nonenal, (E)-2-decenal and (E,E)-2,4-decadienal) against a number of standard and freshly isolated bacterial strains that may be causal agents of human intestinal and respiratory tract infections. The saturated aldehydes characterized in the present study do not exhibit significant antibacterial activity, while the alpha,beta-unsaturated aldehydes have a broad antimicrobial spectrum and show similar activity against Gram-positive and Gram-negative microorganisms. The effectiveness of the aldehydes under investigation seems to depend not only on the presence of the alpha,beta-double bond, but also on the chain length from the enal group and on the microorganism tested.


Asunto(s)
Aldehídos/farmacología , Antibacterianos/farmacología , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Grampositivas/efectos de los fármacos , Magnoliopsida/química , Aldehídos/química , Antibacterianos/química , Microbiología de Alimentos , Listeria monocytogenes/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Salmonella/efectos de los fármacos , Staphylococcus aureus/efectos de los fármacos , Relación Estructura-Actividad
16.
Brain Res Bull ; 33(1): 1-6, 1994.
Artículo en Inglés | MEDLINE | ID: mdl-8275321

RESUMEN

In the present study the water and ion (Na+, K+, Ca2+, Fe3+, Se4+, Mg2+, Mn2+, Mn2, Se4+, Cu2+) content in the brain of genetically epilepsy-prone rats (GEPRs) and of 21-, 45-, and 60-day-old DBA/2 mice were determined, and compared with those measured in normal controls (Sprague-Dawley rats and Swiss mice), to verify whether the predisposition to audiogenic seizures (AGS) may be partially related to changes in the cerebral osmotic and ionic state. Our findings clearly evidenziate two points: a) a more complex shift in brain ionic balance (rather than a peculiar modification in the concentration of a single ion) seems very likely involved in AGS susceptibility; (b) brain Ca2+ and Se4+ amounts, together with the water content, appear to be really important factors to which a role in abnormal seizure predisposition may be attributed.


Asunto(s)
Química Encefálica/fisiología , Cationes/metabolismo , Epilepsia/metabolismo , Estimulación Acústica , Análisis de Varianza , Animales , Agua Corporal/metabolismo , Epilepsia/genética , Ratones , Ratones Endogámicos DBA , Ratas , Ratas Sprague-Dawley , Convulsiones/genética , Convulsiones/metabolismo
17.
J Pharmacol Toxicol Methods ; 37(3): 135-41, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9253749

RESUMEN

Large unilamellar vesicles (LUVs) are generally accepted to be a suitable model for peroxidation studies. In the present report, dipalmitoylphosphatidylcholine (DPPC)/linoleic acid-mixed LUVs were employed as model membranes to verify the inhibitory effect of tocopherol (an efficient representative antioxidant) against 2,2'-azobis(2-amidinopropane)hydrochloride-induced peroxidation (evaluated by monitoring conjugated diene accumulation). In this model, the appropriate experimental conditions (particularly, liposome composition and peroxidation temperature) were selected following characterization of bilayer physical state, and not only by evaluation of peroxidation rate. Thus, the experiments described provide a routine screening procedure that would be appropriate for assessing the activity profile of novel free-radical scavengers.


Asunto(s)
1,2-Dipalmitoilfosfatidilcolina/química , Depuradores de Radicales Libres/farmacología , Ácidos Linoleicos/química , Membrana Dobles de Lípidos/química , Peroxidación de Lípido/efectos de los fármacos , Liposomas/química , Amidinas/toxicidad , Antioxidantes/farmacología , Rastreo Diferencial de Calorimetría , Radicales Libres , Ácido Linoleico , Modelos Químicos , Vitamina E/farmacología
18.
Life Sci ; 68(12): 1351-66, 2001 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-11388688

RESUMEN

The aim of this paper was to clarify whether the interaction of the lazaroid U-74389G with phospholipid membranes might be relevant as to its antioxidant activity. Thus we evaluated the "in vitro" antioxidant activity of U-74389G in two experimental models: 1) bleaching of the stable 1,1-diphenyl-2-picrylhydrazyl radical; 2) peroxidation, induced by the water-soluble radical initiator 2,2'-azobis(2-amidino-propane) hydrochloride, on mixed dipalmitoyl-phosphatidylcholine/linoleic acid unilamellar vesicles. Moreover, given that biophysical techniques may help in explaining the role of a drug in its interaction with the microenvironment of the model lipid membranes, we used a classical approach to investigate the U-74389G/model membrane interaction: the differential scanning calorimetry technique on dimyristoylphosphatidylcholine multilamellar and unilamellar vesicles and the Langmuir-Blodgett technique on dimyristoylphosphatidylcholine monolayers. The results evidenced the strong antioxidant activity of U-74389G (especially in a membranous system) and its capability to interact with and be transported across model membranes. Thus one can speculate that U-74389G can act as scavenger of chain-propagating lipid peroxyl radicals within the membranes and may be able to protect not only cell membranes, but also intracellular components against peroxidative attack. Furthermore, also if there is no certain proof that the effect on the lipid packing order may play a key role in its antioxidant activity, the fluidifying effect on phospholipid bilayers of U-74389G favourably complements its free radical scavenging characteristics.


Asunto(s)
Antioxidantes/farmacología , Bepridil/análogos & derivados , Picratos , Pregnatrienos/farmacología , 1,2-Dipalmitoilfosfatidilcolina/metabolismo , Amidinas/metabolismo , Bepridil/metabolismo , Compuestos de Bifenilo , Rastreo Diferencial de Calorimetría , Dexametasona/metabolismo , Depuradores de Radicales Libres/metabolismo , Radicales Libres , Técnicas In Vitro , Ácido Linoleico/metabolismo , Membrana Dobles de Lípidos/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Oxidación-Reducción
19.
J Pharm Sci ; 88(5): 561-7, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10229650

RESUMEN

Nipecotic acid (1), one of the most potent in vitro inhibitors of neuronal and glial gamma-amino butyric acid (GABA) uptake, is inactive as an anticonvulsant when administered systemically. To obtain in vivo active prodrugs of (1), we synthesized four new nipecotic acid esters (3-6), which were obtained by chemical conjugation with glucose, galactose, and tyrosine. These compounds were assayed to evaluate their in vitro chemical and enzymatic hydrolysis. In addition, their anticonvulsant activity was evaluated in vivo in Diluted Brown Agouti (DBA)/2 mice, an excellent animal model for the study of new anticonvulsant drugs. Esters (3-6) appeared stable, at various temperatures, in a pH 7.4 buffered solution and showed susceptibility to undergoing in vitro enzymatic hydrolysis. Intraperitoneally injected nipecotic acid (1) and esters (3-5) did not protect mice against audiogenic seizures; conversely, nipecotic tyrosine ester (6) showed a significant dose-dependent anticonvulsant activity. The in vivo protective activity of the ester (6) and the inefficiency of nipecotic acid (1) in the same experimental conditions suggest that this ester prodrug could be actively transported intact across the blood-brain barrier, beyond which it could be hydrolyzed.


Asunto(s)
Anticonvulsivantes/síntesis química , Ácidos Nipecóticos/síntesis química , Profármacos/síntesis química , Prolina/análogos & derivados , Animales , Barrera Hematoencefálica , Estabilidad de Medicamentos , Femenino , Masculino , Ratones , Ratones Endogámicos DBA , Ácidos Nipecóticos/química , Ácidos Nipecóticos/farmacología , Profármacos/química , Profármacos/farmacología
20.
J Agric Food Chem ; 47(3): 991-5, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10552403

RESUMEN

We carried out an investigation by differential scanning calorimetry (DSC) on the effect of two structurally similar bioactive plant phenols, cinnamic and p-coumaric acids, on the phase transition of model membranes constituted by dimyristoylphosphatidylcholine (DMPC) vesicles. The aim was to evaluate how pH and molecular substituents influence liposolubility and thereby modify vesicle permeability. A change in permeability would result in modifications to the phase transition for DMPC liposomes such that the transition temperature would be lowered and the enthalpy changes should be little affected. Evidence of differences in permeability was obtained by comparing the effects exerted by the two compounds left in touch with unilamellar and multilamellar vesicles, at two different pHs (4 and 7.4). While the p-coumaric acid was unable to appreciably modify the thermotropic behavior of the model membrane, the cinnamic acid interacted with lipid vesicles at both pH's, even if at acidic pH the effect was greater than neutral. It can be hypothesized that the interaction between the cinnamic acid and the lipidic layers is due to the lack of a hydroxyl group. This interaction is enhanced by an acidic pH, where the carboxylic acid is in a protonated form.


Asunto(s)
Cinamatos/química , Ácidos Cumáricos/química , Fenoles/química , Rastreo Diferencial de Calorimetría/métodos , Dimiristoilfosfatidilcolina , Liposomas , Permeabilidad , Relación Estructura-Actividad
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