Fisioloxía
http://hdl.handle.net/10347/2906
2024-03-29T15:46:26ZApplication of a multi-toxin detect method to analyze mycotoxins occurrence in plant-based beverages
http://hdl.handle.net/10347/33114
Application of a multi-toxin detect method to analyze mycotoxins occurrence in plant-based beverages
Rodríguez Cañás, Inés; González Jartín, Jesús María; Alfonso Rancaño, María Amparo; Alvariño Romero, Rebeca; Rodríguez Vieytes, María Mercedes; Botana López, Luis Miguel
In recent years, plant-based beverages have gained popularity on the market due to environmental and ethical concerns, as well as milk intolerances and allergies. However, raw materials employed in the manufacture of these products are susceptible to mycotoxin contamination. For this reason, a new method based on a QuEChERS extraction procedure followed by ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) detection was developed for the analysis of 29 mycotoxins in oat, rice, soy, and almond beverages. The method was validated in terms of linearity, detection and quantification limits, matrix effect, recoveries, accuracy and precision. Satisfactory performance characteristics were achieved, with recoveries above 70% for most mycotoxins. Several commercial samples were analyzed, aflatoxins were frequently detected in rice and almond beverages, while T-2 and HT-2 toxins were identified in oat-based products. In addition, emerging mycotoxins such as enniatins and beauvericin were detected in the four types of beverages
2024-01-01T00:00:00ZAcute toxicology report of the emerging marine biotoxin Brevetoxin 3 in mice: Food safety implications
http://hdl.handle.net/10347/33090
Acute toxicology report of the emerging marine biotoxin Brevetoxin 3 in mice: Food safety implications
Costas Sánchez, Celia; Louzao Ojeda, María Carmen; Raposo García, Sandra; Vale González, María del Carmen; Graña, Almudena; Carrera González, María Cristina; Cifuentes Martínez, José Manuel; Vilariño del Río, Natalia; Rodríguez Vieytes, María Mercedes; Botana López, Luis Miguel
Brevetoxins (PbTxs) are emerging marine toxins that can lead to Neurotoxic Shellfish Poisoning in humans by the ingestion of contaminated seafood. Recent reports on brevetoxin detection in shellfish in regions where it has not been described before, arise the need of updated guidelines to ensure seafood consumers safety. Our aim was to provide toxicological data for brevetoxin 3 (PbTx3) by assessing oral toxicity in mice and comparing it with intraperitoneal administration. We followed an Up-and-Down procedure administering PbTx3 to mice and registering clinical signs, neuromuscular function, histopathology, and blood changes. Neuromuscular dysfunction like seizures and ataxia, as well as loss of limb strength were observed at 6 h. Performance and clinical signs largely improved at 24 h, time at which no blood biochemical or histological alterations were detected independently of the administration route. However, PbTx3 oral administration results in lower toxicity than intraperitoneal administration. Mortality was only observed at 4000 μg/kg bw PbTx3 administered via oral, but we still found toxicity clinical signs at low toxin doses. We could stablish an oral Lowest-Observable-Adverse-Effect-Level for PbTx3 of 100 μg/kg bw and an oral No-Observable-Adverse-Effect-Level of 10 μg/kg bw in mice. The data here reported should be considered in the evaluation of risks of PbTxs for human health
2023-01-01T00:00:00ZGhrelin effects on neuropeptides in the rat hypothalamus depend on fatty acid metabolism actions on BSX but not on gender
http://hdl.handle.net/10347/32558
Ghrelin effects on neuropeptides in the rat hypothalamus depend on fatty acid metabolism actions on BSX but not on gender
Lage Fernández, Ricardo; Vázquez Villar, María Jesús; Varela Fernández, Luis; Saha, Asish K.; Vidal Puig, Antonio; Nogueiras Pozo, Rubén; Diéguez González, Carlos; López Pérez, Miguel Antonio
The orexigenic effect of ghrelin is mediated by neuropeptide Y (NPY) and agouti-related protein (AgRP) in the hypothalamic arcuate nucleus (ARC). Recent evidence also indicates that ghrelin promotes feeding through a mechanism involving activation of hypothalamic AMP-activated protein kinase (AMPK) and inactivation of acetyl-CoA carboxylase and fatty acid synthase (FAS). This results in decreased hypothalamic levels of malonyl-CoA, increased carnitine palmitoyltransferase 1 (CPT1) activity, and mitochondrial production of reactive oxygen species. We evaluated whether these molecular events are part of a unique signaling cascade or whether they represent alternative pathways mediating the orexigenic effect of ghrelin. Moreover, we examined the gender dependency of these mechanisms, because recent evidence has proposed that ghrelin orexigenic effect is reduced in female rats. We studied in both genders the effect of ghrelin on the expression of AgRP and NPY, as well as their transcription factors: cAMP response-element binding protein (CREB and its phosphorylated form, pCREB), forkhead box O1 (FoxO1 and its phosphorylated form, pFoxO1), and brain-specific homeobox transcription factor (BSX). In addition, to establish a mechanistic link between ghrelin, fatty acid metabolism, and neuropeptides, we evaluated the effect of ghrelin after blockage of hypothalamic fatty acid β oxidation, by using the CPT1 inhibitor etomoxir. Ghrelin-induced changes in the AMPK-CPT1 pathway are associated with increased levels of AgRP and NPY mRNA expression through modulation of BSX, pCREB, and FoxO1, as well as decreased expression of endoplasmic reticulum (ER) stress markers in a gender-independent manner. In addition, blockage of hypothalamic fatty acid β oxidation prevents the ghrelin-promoting action on AgRP and NPY mRNA expression, also in a gender-independent manner. Notably, this effect is associated with decreased BSX expression and reduced food intake. Overall, our data suggest that BSX integrates changes in neuronal metabolic status with ARC-derived neuropeptides in a gender-independent manner
"This is the peer reviewed version of the following article: Lage, R., Vázquez, M.J., Varela, L., Saha, A.K., Vidal-Puig, A., Nogueiras, R., Diéguez, C. and López, M. (2010), Ghrelin effects on neuropeptides in the rat hypothalamus depend on fatty acid metabolism actions on BSX but not on gender. The FASEB Journal, 24: 2670-2679, which has been published in final form at https://doi.org/10.1096/fj.09-150672. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. This article may not be enhanced, enriched or otherwise transformed into a derivative work, without express permission from Wiley or by statutory rights under applicable legislation. Copyright notices must not be removed, obscured or modified. The article must be linked to Wiley’s version of record on Wiley Online Library and any embedding, framing or otherwise making available the article or pages thereof by third parties from platforms, services and websites other than Wiley Online Library must be prohibited."
2010-01-01T00:00:00ZEstradiol Regulates Brown Adipose Tissue Thermogenesis via Hypothalamic AMPK
http://hdl.handle.net/10347/32449
Estradiol Regulates Brown Adipose Tissue Thermogenesis via Hypothalamic AMPK
Martínez de Morentín, Pablo B.; González García, Ismael; Martins, Luís; Lage Fernández, Ricardo; Fernández Mallo, Diana; Martínez Sánchez, Noelia; Ruíz Pino, Francisco; Liu, Ji; Morgan, Donald A.; Pinilla, Leonor; Gallego Gómez, María Rosalía; Saha, Asish K.; Kalsbeek, Andries; Fliers, Eric; Bisschop, Peter; Diéguez González, Carlos; Nogueiras Pozo, Rubén; Rahmouni, Kamal; Tena Sempere, Manuel; López Pérez, Miguel Antonio
Estrogens play a major role in the modulation of energy balance through central and peripheral actions. Here, we demonstrate that central action of estradiol (E2) inhibits AMP-activated protein kinase (AMPK) through estrogen receptor alpha (ERα) selectively in the ventromedial nucleus of the hypothalamus (VMH), leading to activation of thermogenesis in brown adipose tissue (BAT) through the sympathetic nervous system (SNS) in a feeding-independent manner. Genetic activation of AMPK in the VMH prevented E2-induced increase in BAT-mediated thermogenesis and weight loss. Notably, fluctuations in E2 levels during estrous cycle also modulate this integrated physiological network. Together, these findings demonstrate that E2 regulation of the VMH AMPK-SNS-BAT axis is an important determinant of energy balance and suggest that dysregulation in this axis may account for the common changes in energy homeostasis and obesity linked to dysfunction of the female gonadal axis
2014-01-01T00:00:00Z