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1.
Biometals ; 36(1): 67-96, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36374356

RESUMO

Cadmium (Cd) is one of the most dangerous heavy metals that exists. A prolonged exposure to Cd causes toxic effects in a variety of tissues, including Central Nervous System (CNS), where it can penetrate the Blood Brain Barrier (BBB). Cd exposure has been linked to neurotoxicity and neurodegenerative diseases. Soy isoflavones have a strong antioxidant capacity, and they have been shown to have positive effects on cognitive function in females. However, the mechanisms underlying Cd neurotoxicity remain completely unresolved. The purpose of this study was to characterize the potential protective effect of a soy-based diet vs. a casein-based diet against Cd toxicity in rat cerebellum. Female Wistar rats were fed with casein (Cas) or soybean (So) as protein sources for 60 days. Simultaneously, half of the animals were administered either 15 ppm of Cadmium (CasCd and SoCd groups) in water or regular tap water as control (Cas and So groups). We analyzed Cd exposure effects on trace elements, oxidative stress, cell death markers, GFAP expression and the histoarchitecture of rat cerebellum. We found that Cd tissue content only augmented in the Cas intoxicated group. Zn, Cu, Mn and Se levels showed modifications among the different diets. Expression of Nrf-2 and the activities of CAT and GPx decreased in Cas and So intoxicated groups,while 3-NT expression increased only in the CasCd group. Morphometry analyses revealed alterations in the purkinje and granular cells morphology, decreased number of granular cells and reduced thickness of the granular layer in Cd-intoxicated rats, whereas no alterations were observed in animals under a So diet. In addition, mRNA expression of apoptotic markers BAX/Bcl-2 ratio and p53 expression increased only in the CasCd group, a finding confirmed by positive TUNEL staining in the cerebellum granule cell layer in the same group. Also, Cd intoxication elicited overexpression of GFAP by astrocytes, which was prevented by soy. White matter alterations were only subtle and characterized by intramyelinic edema in the CasCd group. Overall, these results unmask an irreversible toxic effect of a subchronic Cd intoxication on the cerebellum, and identify a protective role by a soy-based diet with potential as a therapeutic strategy for those individuals exposed to this dangerous environmental contaminant.


Assuntos
Cádmio , Oligoelementos , Ratos , Feminino , Animais , Cádmio/farmacologia , Glycine max , Oligoelementos/farmacologia , Ratos Wistar , Caseínas/metabolismo , Caseínas/farmacologia , Antioxidantes/farmacologia , Dieta , Estresse Oxidativo , Homeostase
2.
Biometals ; 35(2): 229-244, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35038064

RESUMO

Cadmium (Cd) is a toxic metal and an important environmental contaminant. We analyzed its effects on oligoelements, oxidative stress, cell death, Hsp expression and the histoarchitecture of rat lung under different diets, using animal models of subchronic cadmium intoxication. We found that Cd lung content augmented in intoxicated groups: Zn, Mn and Se levels showed modifications among the different diets, while Cu showed no differences. Lipoperoxidation was higher in both intoxicated groups. Expression of Nrf-2 and SOD-2 increased only in SoCd. GPx levels showed a trend to increase in Cd groups. CAT activity was higher in intoxicated groups, and it was higher in Soy groups vs. Casein. LDH activity in BAL increased in CasCd and decreased in both soy-fed groups. BAX/Bcl-2 semiquantitative ratio showed similar results than LDH activity, confirmed by Caspase 3 immunofluorescence. The histological analysis revealed an infiltration process in CasCd lungs, with increased connective tissue, fused alveoli and capillary fragility. Histoarchitectural changes were less severe in soy groups. Hsp27 expression increased in both intoxicated groups, while Hsp70 only augmented in SoCd. This show that a soy-diet has a positive impact upon oxidative unbalance, cell death and morphological changes induced by Cd and it could be a good alternative strategy against Cd exposure.


Assuntos
Antioxidantes , Cádmio , Animais , Antioxidantes/farmacologia , Cádmio/metabolismo , Morte Celular , Dieta , Pulmão , Estresse Oxidativo , Ratos , Glycine max
3.
Diaeta (B. Aires) ; 38(173): 38-48, dic. 2020. graf
Artigo em Espanhol | LILACS, BINACIS, UNISALUD | ID: biblio-1278981

RESUMO

Resumen Introducción. El Zinc (Zn) es un oligoelemento esencial con gran importancia nutricional e indispensable para el crecimiento normal y la reproducción. Su deficiencia produce anormalidades fisiológicas y estructurales. Así mismo, ingerido en altas concentraciones produce efectos tóxicos, de allí la importancia de su determinación. El agua puede contribuir significativamente a la ingesta diaria de elementos trazas, entre ellos Zn. En el presente estudio se analizó el aporte de Zn en muestras de aguas de ríos y de red (de suministro público) de la provincia de San Luis y en agua mineral natural envasada, por medio de fluorescencia en fase sólida (FFS). Materiales y método.La determinación cuantitativa de Zn en muestras de agua y estándares se basó en la complejación del Zn utilizando una mezcla de o-fenantrolina y eosina a pH 7,5. Luego, una microzona de papel de filtro Blue Ribbon se impregna con la mezcla durante 1 minuto (n=6). Posteriormente, los papeles de filtro se secaron a temperatura ambiente y se colocan en una celda de cuarzo convencional adaptada para FFS. Los resultados obtenidos fueron comparados con la técnica de espectrometría de masas con plasma acoplado inductivamente. Resultados. Las muestras de agua de río analizadas presentaron valores por debajo del límite máximo de Zn recomendado por la Ley Nacional 24051, para la protección de la vida acuática. Las concentraciones de Zn en las muestras de agua de consumo analizadas (de red y envasadas) también estuvieron por debajo de los límites máximos permitidos por el Código Alimentario Argentino y la OMS. Por otro lado, se obtuvo buena concordancia entre las metodologías utilizadas. Conclusiones. El contenido de Zn de las muestras analizadas se encuentra por debajo de los valores máximos permitidos por los distintos organismos de regulación. Las muestras de agua analizadas no contribuyen a satisfacer la ingesta diaria recomendada y presentan valores considerablemente menores a los encontrados en otras regiones. Finalmente, el método aplicado mostró ser una alternativa rápida y sensible para la determinación de Zn en muestras de agua.


Abstract Introduction. Zinc (Zn) is an essential trace element with great nutritional importance and indispensable for normal growth and reproduction. Its deficiency produces physiological and structural abnormalities. Also, if ingested in high concentrations, it produces toxic effects; this is why its determination is very important. Water can contribute significantly to the daily intake of trace elements, including Zn. In this work, Zn concentration was analyzed in river and tap water samples of the province of San Luis and in bottled natural mineral water, by means of solid phase fluorescence (SPF). Materials and method. The quantitative determination of Zn in water samples and standards was based on the complexation of Zn using a mixture of o-phenanthroline and eosin at pH 7.5. Then, a microzone of Blue Ribbon filter paper was impregnated with the mixture for 1 minute (n=6). After this, the filter papers were dried at room temperature and placed in a conventional quartz cell adapted for SPF. The results obtained were compared with the Inductively Coupled Plasma - Mass Spectrometry (ICP-MS) technique. Results. The river water samples analyzed were found below the maximum limit of Zn recommended by National Law 24051 for the protection of aquatic life. The Zn concentrations in the analyzed drinking water samples (tap and bottled water) were also below the maximum limits allowed by the CAA and WHO. Furthermore, a good agreement was obtained between the methodologies used. Conclusions. The Zn content in analyzed samples was below the maximum values allowed by different regulatory organizations. The water samples analyzed do not contribute to satisfying the recommended daily intake and have considerably lower values than those found in other regions. Finally, the method applied proved to be a fast and sensitive alternative for the determination of Zn in water samples.


Assuntos
Zinco , Água Potável , Elementos Químicos , Toxicidade
4.
Biometals ; 20(5): 727-41, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17066326

RESUMO

Cadmium is an environmental toxic metal implicated in human prostate carcinogenesis. The mechanism of its toxicity is not fully understood. Previously, we showed that cadmium exposure induces oxidative stress, especially lipid peroxidation. This study evaluates the effect of chronic exposure to 0.886 mM of cadmium (Cd) per liter in the drinking water on prostate lipid content and metabolism in Wistar rats. We determined the lipid profile and measured the expression of lipogenic enzymes: FAS, GPAT, LPL, DGAT-1, DGAT-2, ACO, CPT-1 and CT, and of certain factors involved in lipid regulation and fatty acid transporters: FAT/CD36, E-FABP, SREBP-2, PPAR-gamma and PPAR-alpha by RT-PCR. Ultrastructure was analyzed by electron microscopy and, as prostate is an androgen controlled gland, AR expression was measured by RT-PCR and Western blot. Cd altered the prostatic lipid profile. Triglycerides (TG) and esterified cholesterol (EC) decreased, free cholesterol (FC) and phospholipids (PL) increased and total cholesterol (TC) did not change. FAS, MDH and IDH activities did not vary but G6PDH decreased significantly in Cd group. Regarding TG synthesis, DGAT-1 decreased while GPAT increased and FAS, LPL and DGAT-2 remained unchanged. Regarding beta oxidation, CPT-1 increased while ACO expression decreased in Cd group. In the PL pathway, CT expression was increased. All these results would justify the decrease of TG in Cd group when compared to control. In the cholesterol metabolic pathway, HMGCoAR and SREBP-2 increased. PPAR-alpha increased but PPAR-gamma did not change. Regarding fatty acid transporters, FAT/CD36 decreased, while E-FABP increased. AR mRNA and protein expression decreased. Ultrastructural analysis showed a decrease in lipid droplets and signs of cellular damage in the Cd group. Cadmium exposure induces important changes in prostatic lipid profile and metabolism, confirmed by the morphology analyses, which also showed signs of cellular damage. These results could be important to further understanding the complex mechanism of cadmium toxicity in prostate and in the development of better treatments for people and animals exposed to the heavy metal.


Assuntos
Cádmio/toxicidade , Colesterol/metabolismo , Exposição Ambiental , Próstata/efeitos dos fármacos , Próstata/ultraestrutura , Triglicerídeos/metabolismo , Animais , Colesterol/biossíntese , Humanos , Masculino , Próstata/metabolismo , Próstata/patologia , Ratos , Ratos Wistar , Triglicerídeos/antagonistas & inibidores , Triglicerídeos/biossíntese
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