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1.
Artículo en Inglés | MEDLINE | ID: mdl-36901131

RESUMEN

A growing number of studies have confirmed that microplastics (MPs) contamination represents a worrisome issue of global concern. MPs have been detected in the atmosphere, in aquatic and terrestrial ecosystems, as well as in the biota. Moreover, MPs have been recently detected in some food products and in drinking water. However, only limited information is currently available for beverages, although they are largely consumed by humans and might contribute to the ingestion of MPs. Thus, estimating the contamination in beverages represents a crucial step in assessing human MP ingestion. The aim of the present study was to explore the presence of MPs in nonalcoholic beverages, namely soft drinks and cold tea, of different brands purchased in supermarkets and to estimate the contribution of beverage consumption to MP ingestion by humans. The results of the present study confirmed the presence of MPs, mainly fibers, in most of the analyzed beverages, with a mean (± SEM) number of 9.19 ± 1.84 MPs/L. In detail, the number of MPs detected in soft drinks and cold tea was 9.94 ± 0.33 MPs/L and 7.11 ± 2.62 MPs/L, respectively. Our findings confirmed that beverage consumption can be considered one of the main pathways for MP ingestion by humans.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Humanos , Plásticos , Ecosistema , Bebidas , , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
2.
J Exp Biol ; 222(Pt 10)2019 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-31043457

RESUMEN

Variation in the concentration of antioxidants and hormones of maternal origin in the eggs of birds can have a profound influence on offspring phenotype both prenatally and postnatally. Egg maternal substances can have interacting effects, but experimental studies of the consequences of the combined variation in the egg concentration of such molecules are extremely rare, particularly as far as prenatal stages are concerned. We manipulated the yolk concentration of vitamin E and corticosterone, which are, respectively, the main antioxidant and the main glucocorticoid hormone in bird eggs, both independently and simultaneously, and we tested their separate and combined effects on growth and oxidative status in the liver and in the brain of yellow-legged gull (Larus michahellis) embryos. Egg supplementation of relatively large physiological doses of corticosterone depressed embryo growth (total body mass, tarsus length and liver mass), whereas administration of vitamin E in association with corticosterone restored normal growth. Vitamin E did not affect embryo growth when administered alone. We further analysed the independent and combined effects of vitamin E and corticosterone on liver and brain total antioxidant capacity, the concentration of reactive oxygen molecules and lipid peroxidation. Vitamin E significantly reduced liver total antioxidant capacity, while corticosterone depressed brain lipid peroxidation. Prenatal exposure to vitamin E and corticosterone appears to have antagonistic effects on body growth, although vitamin E is not limiting in yellow-legged gull eggs. In combination with the results of previous experiments on the same species applying smaller experimental doses or focusing on the postnatal rather than prenatal life stages, our findings indicate that the effects of a physiological increase in the egg concentration of these substances can be life stage and dose specific, implying that generalizing prenatal effects of egg compounds may not be feasible.


Asunto(s)
Charadriiformes/fisiología , Corticosterona/administración & dosificación , Yema de Huevo/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Vitamina E/administración & dosificación , Animales , Embrión no Mamífero/efectos de los fármacos , Femenino , Masculino , Vitaminas/administración & dosificación
3.
Curr Zool ; 64(3): 285-292, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30402069

RESUMEN

Parental effects occur whenever the phenotype of parents or the environment that they experience influences the phenotype and fitness of their offspring. In birds, parental effects are often mediated by the size and biochemical quality of the eggs in terms of maternally transferred components. Exogenous antioxidants are key egg components that accomplish crucial physiological functions during early life. Among these, vitamin E plays a vital role during prenatal development when the intense metabolism accompanying rapid embryo growth results in overproduction of pro-oxidant molecules. Studies of captive birds have demonstrated the positive effect of vitamin E supplementation on diverse phenotypic traits of hatchling and adult individuals, but its effects on embryo phenotype has never been investigated neither in captivity nor under a natural selection regime. In the present study, we experimentally tested the effect of the in ovo supplementation of vitamin E on morphological traits and oxidative status of yellow-legged gull (Larus michahellis) embryos. The supplementation of vitamin E promoted somatic growth in embryos soon before hatching, but did not affect their oxidative status. Our results suggest that maternally transferred vitamin E concentrations are optimized to prevent imbalances of oxidative status and the consequent raise of oxidative damage in yellow-legged gull embryos during prenatal development.

4.
Phytomedicine ; 38: 158-165, 2018 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-29425648

RESUMEN

BACKGROUND: In recent years, it has been demonstrated the inhibitory effect of some plant species on the angiotensin-converting enzyme and rosmarinic acid is a prominent constituent of these species. HYPOTHESIS/PURPOSE: This study was carried out to verify the effect of rosmarinic acid on blood pressure through inhibitory activity on angiotensin-converting enzyme in rats. STUDY DESIGN: The arterial hypertension was promoted using 2-kidneys 1-clip model in rats. The potential inhibitory rosmarinic acid effect on angiotensin-converting enzyme activity was compared with captopril actions by analyzing in vivo blood pressure dose-response curves to angiotensin I and bradykinin. The in vitro plasma angiotensin-converting enzyme activity was measured by fluorimetry using the substrate Abz-FRK(Dnp)P-OH substrate. In addition, dosages of nitrite/nítrate analysis were carried out. RESULTS: (1) rosmarinic acid caused systolic blood pressure dose-dependent decrease in hypertensive rats; (2) The angiotensin I dose-response curves demonstrated that rosmarinic acid promotes minor changes in systolic blood pressure only in the hypertensive group; (3) The bradykinin dose-response curves showed that both rosmarinic acid and captopril promoted a systolic blood pressure reduction, but only the captopril effect was significant; (4) The angiotensin-converting enzyme activity in rat lung tissue was inhibited by the rosmarinic acid in a dose dependent manner; (5) The analysis of nitrite/nítrate plasma concentrations showed no significant difference among the experimental groups. CONCLUSION: The rosmarinic acid is effective in reducing blood pressure, selectively, only in hypertensive animals. The rosmarinic acid (173µM) promoted almost a 98.96% reduction on angiotensin-converting enzyme activity.


Asunto(s)
Presión Sanguínea/efectos de los fármacos , Cinamatos/farmacología , Depsidos/farmacología , Hipertensión/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Animales , Antihipertensivos/farmacología , Bradiquinina/farmacología , Captopril/farmacología , Relación Dosis-Respuesta a Droga , Pulmón/efectos de los fármacos , Pulmón/metabolismo , Masculino , Peptidil-Dipeptidasa A/metabolismo , Ratas Wistar , Ácido Rosmarínico
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