Molecular signatures associated with diuron exposure on rat urothelial mitochondria.

Diuron, 3-(3,4-dichlorophenyl)-1,1-dimethylurea, is a worldwide used herbicide whose biotransformation gives rise to the metabolites, 3-(3,4-dichlorophenyl)-1-methylurea (DCPMU) and 3,4-dichloroaniline (DCA). Previous studies indicate that diuron and/or its metabolites are toxic to the bladder urothelium of the Wistar rats where, under certain conditions of exposure, they may induce successively urothelial cell degeneration, necrosis, hyperplasia and eventually tumors. The hypothesis was raised that the molecular initiating event (MIE) of this Adverse Outcome Pathway is the mitochondrial toxicity of those compounds. Therefore, this study aimed to investigate in vitro the metabolic alterations resulting from urothelial mitochondria isolated from male Wistar rats exposure to diuron, DCPMU and DCA at 10 and 100 µM. A non-targeted metabolomic analysis using mass spectrometry showed discriminative clustering among groups and alterations in the intensity abundance of membrane-associated molecules phosphatidylcholine, phosphatidylinositol and phosphatidylserine, in addition to methylhexanoyl-CoA and, particularly for diuron 100 µM, dehydro-L-gulonate, all of them involved in critical mitochondrial metabolism. Collectively, these data indicate the mitochondrial dysfunction as an MIE that triggers cellular damage and death observed in previous studies.

Flaxseed oil rich in omega-3 protects aorta against inflammation and endoplasmic reticulum stress partially mediated by GPR120 receptor in obese, diabetic and dyslipidemic mice models.

The "first hit" to atherogenesis is driven by toll-like receptor 4, endoplasmic reticulum stress and ultimately metabolic dysfunction. In this study, we hypothesized that a flaxseed oil-enriched diet (FS) abolishes these inflammatory signaling pathway and restore metabolic homeostasis by activating the fatty acid receptor GPR120 in aorta of obese mice. Glucose homeostasis was assessed by GTT and ITT; lipidomics was performed using a Hybrid Ion Trap-Orbitrap Mass Spectrometer; serum lipids were measured using colorimetric assays; GPR120 and infiltrating macrophages were analyzed by immunofluorescence; protein immunoprecipitation and gene expression were evaluated by Western blot and RT-PCR, respectively. There were no differences in body weight and food intake between the groups from both strains (Swiss and LDLr-KO mice). GTT and cholesterol levels were improved by FS in both mice models. Lipidomics showed an increase in ω3 (C18:3) content, meanwhile stearic acid (C18:0) was not detected in endothelial tissue in response to FS. Moreover, FS markedly decreased pro-inflammatory (IL-1ß, TNF-α, pIκBα, pIKKß) and unfolded protein response markers (ATF6 and GRP78) in aorta. In Swiss mice, GPR120 was partially involved in the ω3-mediated anti-inflammatory actions, disrupting TLR4 pathway, but not in LDLr-KO mice. Partial replacement of dietary saturated by unsaturated ω3 fatty acids contributes to inhibition of cardiovascular risk markers, pro-inflammatory cytokines and ER stress sensors and effectors in the aorta. However, downregulation of inflammation is not mediated by arterial GPR120 activation.

Determinaçao de folatos em espinafre - avaliaçao da influência do tipo de cultivo, época de colheita e cozimento / Folate determination in spinach: influence of cultivation, harvest and cooking methods

O objetivo desse trabalho foi e avaliar o teor das diferentes formas da vitamina, em espinafres produzidos por diferentes tipo de cultivo (orgâ e tradicional), distintas épocas de colheita e após cozimento em água. Para tanto utilizou-se a técnica de cromatografia líquida de alta eficiência. Espinafres cultivados de forma tradicional e orgânica não apresentaram diferença significativa nos teores de folatos, assim como tambén não se observou diferença significativa entre valores obtidos em diferentes períodos do ano. Os níveis de folatos medidos como 5-metilTHF e 5-formilTHF, variaram de 226 a 527 µg/100g e 4.6 to 10µ/100g, respectivamente. O cozimento em água resultou em perdas de aproximadamente 74 porcento para o 5-metilTHF e 56 porcento para o 5-formilTHF. Com base na determinação da concentração de folatos na água de cozimento, pode-se afirmar que as perdas se deram, principalemente, devido ao processo de lixiviação.

Aflatoxin screening by MALDI-TOF mass spectrometry.

Efficient detection of aflatoxins B1, B2, G1, and G2 has been performed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a UV-absorbing ionic liquid matrix to obtain "matrix-free" mass spectra and addition of NaCl to enhance sensitivity via Na+ cationization. Using ionic alpha-cyano-4-hydroxycinnamic acid (Et3N-alpha-CHCA) as the matrix, matrix-free mass spectra in the m/z range of interest are acquired, and the B1, B2, G1, and G2 aflatoxins are readily detected with an LOD as low as 50 fmol. The technique is fast, requires little sample preparation and no derivatization or chromatographic separation, and seems therefore to be suitable for high-throughput aflatoxin screening. It should be easily extended to other micotoxins and provide an attractive technique to control the quality of major crops subjected to huge world commercial trades such as peanuts, corn, and rice as well as to monitor bioterrorism threats by micotoxin poisoning.