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Early modulation of the transcription factor Nrf2 in rodent striatal slices by quinolinic acid, a toxic metabolite of the kynurenine pathway

ANA LAURA COLIN GONZALEZ ARMANDO LUNA LOPEZ MINA KONIGSBERG FAINSTEIN JOSE PEDRAZA CHAVERRI ABEL SANTAMARIA DEL ANGEL (2014)

Nuclear factor (erythroid-derived 2)-like 2 (Nrf2) is a transcription factor involved in the orchestration of antioxidant responses. Although its pharmacological activation has been largely hypothesized as a promising tool to ameliorate the progression of neurodegenerative events, the actual knowledge about its modulation in neurotoxic paradigms remains scarce. In this study, we investigated the early profile of Nrf2 modulation in striatal slices of rodents incubated in the presence of the toxic kynurenine pathway metabolite, quinolinic acid (QUIN). Tissue slices from rats and mice were obtained and used throughout the experiments in order to compare inter-species responses. Nuclear Nrf2 protein levels and oxidative damage to lipids were compared. Time– and concentration–response curves of all markers were explored. Nrf2 nuclear activation was corroborated through phase 2 antioxidant protein expression. The effects of QUIN on Nrf2 modulation and oxidative stress were also compared between slices of wild-type (Nrf2+/+) and Nrf2 knock-out (Nrf2−/−) mice. The possible involvement of the N-methyl-d-aspartate receptor (NMDAr) in the Nrf2 modulation and lipid peroxidation was further explored in mice striatal slices. In rat striatal slices, QUIN stimulated the Nrf2 nuclear translocation. This effect was accompanied by augmented lipid peroxidation. In the mouse striatum, QUIN per se exerted an induction of Nrf2 factor only at 1 h of incubation, and a concentration–response effect on lipid peroxidation after 3 h of incubation. QUIN stimulated the striatal content of phase 2 enzymes. Nrf2−/− mice were slightly more responsive than Nrf2+/+ mice to the QUIN-induced oxidative damage, and completely unresponsive to the NMDAr antagonist MK-801 when tested against QUIN. Findings of this study indicate that: (1) Nrf2 is modulated in rodent striatal tissue in response to QUIN; (2) Nrf2−/− striatal tissue was moderately more vulnerable to oxidative damage than the Wt condition; and (3) early Nrf2 up-regulation reflects a compensatory response to the QUIN-induced oxidative stress in course as part of a general defense system, whereas Nrf2 down-regulation might contribute to more intense oxidative cell damage.

Article

BIOLOGÍA Y QUÍMICA Ciencias de la vida Envejecimiento Aging Estrés oxidativo Oxidative Stress Daño de ADN DNA damage Antioxidantes Antioxidants

Solutions and type curves of a fluid flow model for naturally fractured reservoirs with influx recharge

LUIS XAVIER VIVAS CRUZ JORGE ADRIAN PERERA BURGOS MARCO ANTONIO TANECO HERNANDEZ JOSE ALFREDO GONZALEZ CALDERON (2020)

Modeling of fluid flow considering radially symmetric reservoirs is common in groundwater science and petroleum engineering. The Hankel transform is suitable for solving boundary value problems, considering this flow geometry. However, there are few applications of this transform for reservoirs with a finite wellbore radius, although there are formulas of the finite Hankel transform for homogeneous boundary conditions. In this work, we refer to them as the Cinelli formulas, which are used to obtain novel solutions for transient fluid flow in bounded naturally fractured reservoirs with time-varying influx at the outer boundary, i.e., a technique to incorporate inhomogeneous boundary conditions based on the Cinelli formulas is developed. An analysis shows that the results of the solutions are highly oscillating and slowly convergent. Nevertheless, we show that this problem is largely overcome when the long-time solution is expressed as a closed relationship. Accordingly, we present the characteristic drawdown pressure curves and its Bourdet derivatives for a double-porosity reservoir with influx recharge. These curves allow us to distinguish between the pressure drops of a single-porosity reservoir with influx recharge from that of a double-porosity closed reservoir, which have been stated in the literature to resemble one another. Similarly, double- and triple-porosity reservoirs are analyzed.

Article

FLUID FLOW MODEL NATURALLY FRACTURED RESERVOIR INFLUX AT THE OUTER BOUNDARY JOINT LAPLACE-HANKEL TRANSFORM CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO HIDROLOGÍA HIDROBIOLOGÍA HIDROBIOLOGÍA

Asociación entre determinantes sociales de salud y estrés agudo en madres con neonatos hospitalizados

MAYRA DEL CARMEN ORTEGA JIMENEZ (2016)

Introducción: Las madres representan un pilar en los cuidados del recién nacidos y cuando estos se encuentran en un área crítica o en un área de hospitalización, presentan estrés agudo, reaccionando con nerviosismo y llanto desarrollando alteraciones psicológicas. Dentro de los aspectos de las madres se encuentran los determinantes sociales de salud los cuales son todas aquellas condiciones, en que las personas nacen, crecen, viven trabajan y envejecen los cuales son atribuidos dentro de esta investigación a tener asociación con el estrés maternal, introduciendo la teoría de Ramona T. Mercer que engloba el rol maternal.

Objetivo: Determinar la asociación, efecto e impacto de los determinantes sociales de salud y escolaridad como principal, sobre la presencia de estrés agudo en madres de neonatos hospitalizados en el Hospital General de Celaya y Hospital Materno de Celaya Gto, México.

Material y métodos: Cuantitativo, correlacional, no experimental transversal comparativo. La población de estudio fueron madres con neonatos hospitalizados. El tamaño de la muestra 66 (incrementado a 133) sujetos con muestreo de aleatorización simple. Se utilizó el instrumento de estrés maternal, y un aparatado con los determinantes sociales a estudiar.

Resultados: Para la categoría de estrés arroja una X2 5.24, gl 1,p de 0.02, RM de 0.37, con un IC de 0.16 a 1.90 y una FAe de 63%.

Conclusiones: se observa que hay una significancia fuerte sobre estrés excesivo y escolaridad. Hay asociación entre escolaridad y presencia de estrés. De acuerdo a la teoría del rol maternal la adaptación de la madre a su nuevo rol está dado por un periodo de 12 meses.

Introduction: Mothers represent a pillar in the care of newborns and when they are in a critical area or in an area hospital, have acute stress, reacting nervously and crying developing psychological disorders. Among the aspects of the mothers are the social determinants of health which are all conditions in which people are born, grow, live, work and age which are attributed in this research to have association with maternal stress, are introduces the theory of Ramona T. Mercer that includes the maternal role.

Objetive: To determine the association, effect and impact of the social determinants of health and education as the main, on the presence of acute stress in mothers of hospitalized infants in the General Hospital and Maternity Hospital Celaya Celaya Guanajuato, Mexico.

Methods: Quantitative, correlational, not experimental cross comparison. The study population were mothers with infants hospitalized. The sample size 66 (increased to 133) subjects with simple randomization sampling. The instrument of maternal stress and aparatado with social determinants study was used.

Results: For the category of stress sheds X2 5.24, df 1, p 0.02, RM 0.37, with a CI of 0.16 to 1.90 and AED 63%.

Conclusions: We observed that there is a strong significance on excessive stress and school. No association between schooling and presence of stress. According to the theory of maternal role adaptation of the mother to her new role he is given for a period of 12 months.

Master thesis

CCS- Maestría en Ciencias de Enfermería MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS CIENCIAS CLÍNICAS Madres Neonatos hospitalizados Determinantes sociales de la salud Estrés psicológico Mothers Hospitalized newborns Social determinants of health Psychological stress

Synthesis of keratine, silver, and flavonols nanocomposites to inhibit oxidative stress in pancreatic beta-cell (INS-1) and reduce intracellular reactive oxygen species production

ROSA MARTHA PEREZ GUTIERREZ ISIS SCHERAZADA RODRIGUEZ CLAVEL SILVIA PATRICIA PAREDES CARRERA JESUS CARLOS SANCHEZ OCHOA ALETHIA MUÑIZ RAMIREZ SUSANNA EDITH MEDELLIN GARIBAY ERI JOEL PAZ GARCIA (2021)

"Flavonols (FLA) from Vaccinium macrocarpon (V. macrocarpon) were identified using high-performance liquid chromatography coupled with mass spectrometry detection. Nanoparticles were prepared using highly crosslinked keratin (KER) from human hair and silver and entrapped with flavonols [KER + FLA + AgNPs]. Nanocomposites were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction, zeta potential, and dynamic light scattering, and release profiles. The interactions between the capping agent and the silver core have been investigated using FTIR spectroscopy H2O2 is a source of Reactive Oxygen Species (ROS) and acts as an activator of oxidative stress affecting NS-1 cells, and the protective effect of the nanocomposites were evaluated against H2O2-induced pancreatic beta-cell damage. LC-MS/MS and HPLC analyses revealed the presence of 12 flavonols in V. macrocarpon plant extract. The cell apoptosis and proliferation, were evaluated by Hoechst 33342 staining, flow cytometry and Cell Counting Kit-8 respectively. Preincubation of the NS-1 cells with 250 mu g/mL of H2O2 induced oxidative stress conditions that show pancreatic beta-cell dysfunction, including ROS, cell death, mitochondrial function, antioxidant enzymes, and lipid peroxidation. Nevertheless, pretreatment with FLA and [KER + FLA + AgNPs] prevented mitochondria disruption, maintained cellular ATP levels, inhibited LDH release, intracellular ROS production, decreased lipid peroxidation, increased expression of antioxidant enzymes (CAT, SOD, and GPx) and GSH levels. These results indicate that nanocomposites could protect rat INS-1 pancreatic beta-cell from H2O2-induced oxidative damage, apoptosis and proliferation by reducing the production of intracellular reactive oxygen species."

Article

Vaccinium macrocarpon Oxidative stress Flavonols Antioxidant enzymes Pancreatic β-cell BIOLOGÍA Y QUÍMICA QUÍMICA QUÍMICA

A noncanonical NF-κB pathway through the p50 subunit regulates Bcl-2 overexpression during an oxidative-conditioning hormesis response

ARMANDO LUNA LOPEZ VIRIDIANA YAZMIN GONZALEZ PUERTOS Jacqueline Romero Ontiveros JOSE LUIS VENTURA GALLEGOS ALEJANDRO ZENTELLA DEHESA LUIS ENRIQUE GOMEZ QUIROZ MINA KONIGSBERG FAINSTEIN (2013)

Cells can respond to damage and stress by activating various repair and survival pathways. One of these responses can be induced by preconditioning the cells with sublethal stress to provoke a prosurvival response that will prevent damage and death, and which is known as hormesis. Bcl-2, an antiapoptotic protein recognized by its antioxidant and prosurvival functions, has been documented to play an important role during oxidative-conditioning hormesis. Using an oxidative-hormetic model, which was previously established in the L929 cell line by subjecting the cells to a mild oxidative stress of 50 μM H₂O₂ for 9 h, we identified two different transductional mechanisms that participate in the regulation of Bcl-2 expression during the hormetic response. These mechanisms converge in activating the nuclear transcription factor NF-κB. Interestingly, the noncanonical p50 subunit of the NF-κB family is apparently the subunit that participates during the oxidative-hormetic response.

Article

BIOLOGÍA Y QUÍMICA Ciencias de la vida Biología celular Químicos inorgánicos Radicales libres Estrés oxidativo Hormesis Respuesta adaptativa Cell biology Inorganic chemicals Free radicals Oxidative stress Adaptative response

Heterologous expression of a novel psychrophilic Cu/Zn superoxide dismutase from Deschampsia antarctica

SERGIO ANGEL GARCIA ECHAURI Manuel Gidekel Ana Gutiérrez Moraga LEANDRO GABRIEL ORDOÑEZ ACEVEDO JUAN ANTONIO ROJAS CONTRERAS Ana Paulina Barba de la Rosa Antonio de León Rodríguez (2009)

"Superoxide dismutase (SOD) catalyzes the conversion of the superoxide radical (O2−) into oxygen and hydrogen peroxide. Deschampsia antarctica is a plant that grows in Antarctica and survives to extreme low temperature and high UV radiation, thus it is an ideal model to study novel antioxidants. A cDNA Cu/Zn-SOD gene from D. antarctica was cloned into a pET vector and expressed in Escherichia coli BL21-SI. 112 mg/L of recombinant Cu/Zn-SOD was attained in batch cultures in bioreactor. Using Ni-affinity gel chromatography, the recombinant Cu/Zn-SOD was recovered with a purity of 90% and a specific enzyme activity of 749 at 25 °C. However, zymogram test showed that the enzyme has more activity at 4 °C. This D. antarctica SOD could be used to reduce the oxidation of refrigerated and frozen foods."

Article

Antioxidant Plant Extremophil Psychrophilic enzyme Photo-oxidation Oxidative stress CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA

Diisononyl Phthalate differentially affects sirtuin expression in the HepG2 cell line

ANA KAREN GUTIERREZ GARCIA Mahua Choudhury Antonio de León Rodríguez (2019)

"Human exposure to phthalates has received special attention due to their possible adverse human health effects. Diisononyl phthalate (DINP) is a plasticizer still widely used in many products, despite being considered an endocrine disruptor. In this study, we evaluated DINP’s cytotoxicity, its effect on the levels of reactive oxygen species (ROS), and its effect on sirtuin expression in HepG2 cells. Results showed that 1 μg/mL DINP significantly downregulated Sirt1, Sirt2, Sirt3, and Sirt5 gene expression (p < 0.05), while other sirtuins remained unaffected. Furthermore, protein levels of Sirt1 and Sirt3 were significantly downregulated by 1 μg/mL DINP. On the other hand, 100 μg/mL DINP doubled the levels of lysine acetylation proteins (increased 2-fold) as well as reactive oxygen species (ROS) compared with the controls. In conclusion, our study suggests, for the first time, that DINP regulates the potential epigenetic disruptor sirtuin family and leads to induction of ROS via sirtuins."

Article

Peptides and proteins Genetics Free radicals Organic compounds Oxidative stress MEDICINA Y CIENCIAS DE LA SALUD CIENCIAS MÉDICAS FARMACOLOGÍA FARMACOLOGÍA