No abstract

No abstract

No abstract

Enniatins (ENs) are depsipeptide mycotoxins produced by Fusarium fungi. They are known for their capacity to modulate cell membrane permeability and disruption of ionic gradients, affecting cell homeostasis and initiating oxidative stress mechanisms. The effect of the acute toxicity of ENs A, A1, B and B1 at two different concentrations after 8 h of exposure was analysed in Wistar rats by a transcriptional approach. The following key mitochondrial and nuclear codified genes related to the electron transport chain were considered for gene expression analysis in stomach, liver, kidney and lower intestine by quantitative Real-Time PCR: mitochondrially encoded NADH dehydrogenase 1 (MT-ND1), mitochondrially encoded cytochrome c oxidase 1 (MT-COX1), succinate dehydrogenase flavoprotein subunit A and ATP synthase F1 subunit alpha, respectively. Moreover, the expression of markers involved in oxidative stresssuperoxide dismutase 1 (SOD1), glutathione peroxidase 1 (Gpx1), heme oxygenase 1, apoptosis B-cell lymphoma 2, Bcl2 Associated protein X (Bax), tumor suppressor protein (p53), inhibition of apoptosis nuclear factor kappa of activated B cells, immune system interleukin 1β and intestinal tight junction Occludin merely in lower intestine tissues have been investigated. For mitochondrial genes, the main differences were observed for MT-ND1 and MT-COX1, showing its deficiency in all selected organs. With regard to the intestinal barrier’s cellular response to oxidative stress, the activity of the antioxidant gene SOD1 was decreased in a dose-dependent manner. Similarly, the catalytic enzyme GPx1 was also downregulated though merely at medium dose employed. On the contrary, the pro-apoptotic Bax and p53 regulators were activated after ENs exposure, reporting a significant increase in their expression. Furthermore, the alteration of intestinal permeability was assessed by the abnormal activity of the tight junction protein occludin. In summary, ENs may generate mitochondrial disorders and induce oxidative stress in intestinal barrier function.

No abstract

The beneficial effect of fermented whey and pumpkin extract rich in carotenoids was evaluated in Jurkat cells against aflatoxin B1 (AFB1) and ochratoxin A (OTA) cytotoxicity through a proteomic approach. The functional ingredients were added into mycotoxin contaminated bread formulation, which were digested in vitro in order to simulate human intestinal absorption. Cell cultures were exposed during 7 days to these mycotoxins dissolved in: (a) 0.1% organic solvent (DMSO), (b) an intestinal digest of bread with pumpkin individually (PID) and (c) an intestinal digest of bread with pumpkin mixed with fermented whey (PID+WF). Extracted proteins were subjected to reduction and alkylation and subsequently a tryptic digestion in order to be analysed by liquid chromatography coupled with quadrupole time of flight (LC/MS-Q-TOF). Results obtained highlighted the beneficial role of functional ingredients employed through the identification of proteins involved in several biological processes and metabolic pathways, mainly antioxidant activity, nucleosome assembly and secretory senescence phenotype. Among proteins involved in antioxidant activity, peroxiredoxin 1 and 2 stand out. Comparing the different conditions investigated, a remarkable change was observed in their expression, ranging from a repression using the standard (DMSO 0.1%), to an overexpression when treated with the functional ingredients. Similarly, after PID and PID+WF treatment, histones’ expression implicated in the metabolic pathway of nucleosome assembly, such as H2A, H2B, H2C, H3 and H4, was increased. Furthermore, the expression of protein cyclin A2, which downregulation is involved in limiting carcinogenic cells growth, was lower in presence of both functional ingredients. Based on these findings, functional ingredients can act as protectors against genomic stress caused by mycotoxins, preventing the loss of vital cell functions and paralysing the growth of carcinogenic cells.

No abstract

Mycotoxin contamination of foodstuffs is a health concern worldwide and monitoring human exposure to mycotoxins is a key concern. Most mycotoxins and their metabolites are excreted in urine, but a reliable detection method is required, considering the low levels present in this biological sample. The aim of this work is to validate a sensitive methodology capable of simultaneously determining ten targeted mycotoxins as well as detecting untargeted ones by using Liquid Chromatography coupled to Quadrupole Time of Flight Mass Spectrometry (LC-Q-TOF-MS). The targeted mycotoxins were: enniatin A, B, A1, and B1, beauvericine, aflatoxin B1, B2, G1 and G2, and ochratoxin A. Several extraction procedures such as liquid-liquid extraction, dilute and shoot, and QuEChERS were assessed. Finally, a modified simple QuEChERS extraction method was selected. Creatinine adjustment and matrix-matched calibration curves are required. The limit of detection and limit of quantification values ranged from 0.1 to 1.5 and from 0.3 to 5 ng/mL, respectively. Recoveries achieved were higher than 65% for all mycotoxins. Later, the method was applied to 100 samples of women’s urine to confirm the applicability and determine their internal exposure. The untargeted mycotoxins most found were trichothecenes, zearalenones, and ochratoxins.