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Peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α is a transcriptional coactivator described as a master regulator of mitochondrial biogenesis and function, including oxidative phosphorylation and reactive oxygen species detoxification. PGC-1α is highly expressed in tissues with high energy demands, and it is clearly associated with the pathogenesis of metabolic syndrome and its principal complications including obesity, type 2 diabetes mellitus, cardiovascular disease, and hepatic steatosis. We herein review the molecular pathways regulated by PGC-1α, which connect oxidative stress and mitochondrial metabolism with inflammatory response and metabolic syndrome. PGC-1α regulates the expression of mitochondrial antioxidant genes, including manganese superoxide dismutase, catalase, peroxiredoxin 3 and 5, uncoupling protein 2, thioredoxin 2, and thioredoxin reductase and thus prevents oxidative injury and mitochondrial dysfunction. Dysregulation of PGC-1α alters redox homeostasis in cells and exacerbates inflammatory response, which is commonly accompanied by metabolic disturbances. During inflammation, low levels of PGC-1α downregulate mitochondrial antioxidant gene expression, induce oxidative stress, and promote nuclear factor kappa B activation. In metabolic syndrome, which is characterized by a chronic low grade of inflammation, PGC-1α dysregulation modifies the metabolic properties of tissues by altering mitochondrial function and promoting reactive oxygen species accumulation. In conclusion, PGC-1α acts as an essential node connecting metabolic regulation, redox control, and inflammatory pathways, and it is an interesting therapeutic target that may have significant benefits for a number of metabolic diseases.

[EN] New pedagogical methodologies in the field of health sciences are a necessary and important tool for students in training. At the moment we are living an exceptional situation due to the "COVID" pandemic. This has forced us to implement new learning methodologies. In the present study we evaluated the acquisition of basic competences for the application of knowledge, communication and interpretation of relevant data to make judgements in practices in students of the health sciences degree who carried out theoretical lessons and online practices using new tools and methodologies in comparison with students who carried out lectures and practices prior to COVID. The participants in the study were n=441 nursing and dentistry students, who were divided into 2 study groups; master class Group, and Online Group. A questionnaire was carried out to assess the acquisition of knowledge and the degree of satisfaction. The results obtained showed a significant increase in the maximum number of questions answered correctly and a higher degree of satisfaction of the students in the online group. We can conclude that the implementation of online classes and the application of new educational innovation methodologies in internships show better results in the acquisition of knowledge., [ES] La introducción de nuevas metodologías pedagógicas en el ámbito de ciencias de la salud es una herramienta necesaria para los alumnos en formación. El momento que vivimos ahora con la “época COVID”, ha obligado a implantar nuevas metodologías de aprendizaje. En el presente estudio se evaluó la adquisición de competencias básicas de aplicación de conocimientos, comunicación e interpretación de datos relevantes para emitir juicios en las prácticas en alumnos del grado de ciencias de la salud que realizaron sesiones teóricas online y prácticas mediante nuevas herramientas y metodologías en comparación con los alumnos que realizaron sesiones teóricas magistrales y prácticas anteriores al covid. Los participantes en el estudio fueron n=441 estudiantes de enfermería y odontología, los cuales se dividieron en 2 grupos de estudio; Grupo Presencial, y Grupo Online. Se realizó un cuestionario para evaluar la adquisición de conocimientos y el grado de satisfacción. Los resultados obtenidos demostraron un aumento significativo en el máximo número de preguntas correctamente contestadas y un mayor grado de satisfacción de los alumnos del grupo online. Podemos concluir que la realización de clases online y la aplicación de nuevas metodologías de innovación educativa en las prácticas presenta mejores resultados en la adquisición de conocimientos.

Background: Aspartame is an artificial sweetener used in foods and beverages worldwide. However, it is linked to oxidative stress, inflammation, and liver damage through mechanisms that are not fully elucidated yet. This work aimed to investigate the effects of long-term administration of aspartame on the oxidative and inflammatory mechanisms associated with liver fibrosis progression in mice. Methods: Mice were divided into two groups with six animals each: control and aspartame. Aspartame (80 mg/kg, via oral) or vehicle was administrated for 12 weeks. Results: Aspartame caused liver damage and elevated serum transaminase levels. Aspartame also generated liver fibrosis, as evidenced by histology analysis, and pro-fibrotic markers&rsquo, upregulation, including transforming growth factor &beta, 1, collagen type I alpha 1, and alpha-smooth muscle actin. Furthermore, aspartame reduced nuclear factor erythroid 2-related factor 2 (Nrf2) activation and enzymatic antioxidant activity and increased lipid peroxidation, which triggered NOD-like receptor containing protein 3 (NLRP3) inflammasome activation and p53 induction. Furthermore, aspartame reduced peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1&alpha, ) levels, possibly through p53 activation. This PGC-1&alpha, deficiency could be responsible for the changes in lipid profile in serum, total lipid accumulation, and gluconeogenesis impairment in liver, evidenced by the gluconeogenic enzymes&rsquo, downregulation, thus causing hypoglycemia. Conclusions: This work provides new insights to understand the mechanisms related to the adverse effects of aspartame on liver tissue.

[EN] Among the most novel transformations our educational model has undergone, we find the introduction of innovative teaching methodologies that seek to promote the autonomous work of the student. In the subject of Human Physiolgy, practical teaching is essential. However, students need an extensive theoretical review previous to the practical lesson that consume a significant part of the time allocated to practical learning. In this work, we have developed an innovative teaching methodology that encourages students of the Degree in Optics and Optometry of the University of Valencia to prepare practical lessons in advance by solving previous questionnaires in MOODLE. This enhances their ability of assimilating practical concepts as they obtain better qualifications in questionnaires designed to evaluate the effectiveness of this innovative methodology. In addition, by using a satisfaction survey, we found a high degree of acceptance among the students. Therefore, by fostering the review of theoretical content using MOODLE platform, it is possible to significantly improve the understanding of practical concepts and contribute to improve teaching quality., [ES] Entre las transformaciones más novedosas que ha experimentado nuestro modelo educativo se encuentran la introducción de metodologías docentes innovadoras que tratan de potenciar el trabajo autónomo del estudiante. En el ámbito de la Fisiología Humana, la enseñanza práctica es fundamental. Sin embargo, en el momento de la realización de las prácticas el alumnado necesita de un recuerdo teórico extenso que en muchas ocasiones termina por consumir una parte significativa del tiempo que, en realidad, debiera destinarse al aprendizaje práctico. En el presente trabajo hemos desarrollado una metodología docente innovadora que potencia que los alumnos del Grado en Óptica y Optometría de la Universidad de Valencia preparen las clases prácticas con antelación mediante la resolución de unos cuestionarios previos en el entorno virtual MOODLE. Hemos comprobado que la realización de estos cuestionarios mejora su capacidad para asimilar los contenidos prácticos ya que obtienen mejores calificaciones en unos cuestionarios post-práctica diseñados para evaluar en este caso, la eficacia de la presente innovación. Además, al utilizar una encuesta de satisfacción, hemos observado que se trata de una metodología con un amplio grado de aceptación entre los estudiantes. Por tanto, concluimos que al fomentar el repaso de los contenidos teóricos utilizando para ello un entorno atractivo como es la plataforma MOODLE, se consigue mejorar significativamente el grado de comprensión de los conceptos prácticos, lo que también contribuye a mejorar la calidad docente.

Hepatocellular carcinoma (HCC) represents 80% of the primary hepatic neoplasms. It is the sixth most frequent neoplasm, the fourth cause of cancer-related death, and 7% of registered malignancies. Sorafenib is the first line molecular targeted therapy for patients in advanced stage of HCC. The present study shows that Sorafenib exerts free radical scavenging properties associated with the downregulation of nuclear factor E2-related factor 2 (Nrf2)-regulated thioredoxin 1 (Trx1) expression in liver cancer cells. The experimental downregulation and/or overexpression strategies showed that Trx1 induced activation of nitric oxide synthase (NOS) type 3 (NOS3) and S-nitrosation (SNO) of CD95 receptor leading to an increase of caspase-8 activity and cell proliferation, as well as reduction of caspase-3 activity in liver cancer cells. In addition, Sorafenib transiently increased mRNA expression and activity of S-nitrosoglutathione reductase (GSNOR) in HepG2 cells. Different experimental models of hepatocarcinogenesis based on the subcutaneous implantation of HepG2 cells in nude mice, as well as the induction of HCC by diethylnitrosamine (DEN) confirmed the relevance of Trx1 downregulation during the proapoptotic and antiproliferative properties induced by Sorafenib. In conclusion, the induction of apoptosis and antiproliferative properties by Sorafenib were related to Trx1 downregulation that appeared to play a relevant role on SNO of NOS3 and CD95 in HepG2 cells. The transient increase of GSNOR might also participate in the deactivation of CD95-dependent proliferative signaling in liver cancer cells., Graphical abstract Graphical Abstract. Sorafenib reduced ROS/RNS cytoplasmic concentrations which were associated with decreased Nrf2 nuclear translocation, Trx1 expression/activity, and SNO–NOS3 expression and NO intracellular generation in HepG2. The reduction of SNO–NOS3 expression and NO generation might also be influenced by the induction of transient GSNOR expression/activity and reduced NOS3 expression by Sorafenib. The diminution of SNO-CD95 expression by Sorafenib involved reduction of caspase-8 activity and cell proliferation, and increased downstream caspase-3 activity in liver cancer cells.Image 1, Highlights • Sorafenib induces mitochondrial ROS generation, but also acts as nucleophilic scavenger. • Sorafenib reduces Nrf2-depenent Trx1 expression, and SNO–NOS3 and SNO-CD95 ratios. • Sorafenib-related antitumoral in vivo activity involves diminution of Trx1 and SNO-CD95.

Despite the promising neuroprotective effects of uric acid (UA) in acute ischemic stroke, the seemingly pleiotropic underlying mechanisms are not completely understood. Recent evidence points to transcription factors as UA targets. To gain insight into the UA mechanism of action, we investigated its effects on pertinent biomarkers for the most relevant features of ischemic stroke pathophysiology: (1) oxidative stress (antioxidant enzyme mRNAs and MDA), (2) neuroinflammation (cytokine and Socs3 mRNAs, STAT3, NF-κB p65, and reactive microglia), (3) brain swelling (Vegfa, Mmp9, and Timp1 mRNAs), and (4) apoptotic cell death (Bcl-2, Bax, caspase-3, and TUNEL-positive cells). Adult male Wistar rats underwent intraluminal filament transient middle cerebral artery occlusion (tMCAO) and received UA (16 mg/kg) or vehicle (Locke’s buffer) i.v. at 20 min reperfusion. The outcome measures were neurofunctional deficit, infarct, and edema. UA treatment reduced cortical infarct and brain edema, as well as neurofunctional impairment. In brain cortex, increased UA: (1) reduced tMCAO-induced increases in Vegfa and Mmp9/Timp1 ratio expressions; (2) induced Sod2 and Cat expressions and reduced MDA levels; (3) induced Il6 expression, upregulated STAT3 and NF-κB p65 phosphorylation, induced Socs3 expression, and inhibited microglia activation; and (4) ameliorated the Bax/Bcl-2 ratio and induced a reduction in caspase-3 cleavage as well as in TUNEL-positive cell counts. In conclusion, the mechanism for morphological and functional neuroprotection by UA in ischemic stroke is multifaceted, since it is associated to activation of the IL-6/STAT3 pathway, attenuation of edematogenic VEGF-A/MMP-9 signaling, and modulation of relevant mediators of oxidative stress, neuroinflammation, and apoptotic cell death.

Acute pancreatitis is an inflammatory process of the pancreatic tissue that often leads to distant organ dysfunction. Although liver injury is uncommon in acute pancreatitis, obesity is a risk factor for the development of hepatic complications. The aim of this work was to evaluate the role of PGC-1&alpha, in inflammatory response regulation in the liver and its contribution to the detrimental effect of obesity on the liver during acute pancreatitis. For this purpose, we induced acute pancreatitis by cerulein in not only wild-type (WT) and PGC-1&alpha, knockout (KO) mice, but also in lean and obese mice. PGC-1&alpha, levels were up-regulated in the mice livers with pancreatitis. The increased PGC-1&alpha, levels were bound to p65 to restrain its transcriptional activity toward Nos2. Lack of PGC-1&alpha, favored the assembly of the p65/phospho-STAT3 complex, which promoted Nos2 expression during acute pancreatitis. The increased transcript Nos2 levels and the pro-oxidant liver status caused by the down-regulated expression of the PGC-1&alpha, dependent antioxidant genes enhanced nitrosative stress and decreased energy charge in the livers of the PGC-1&alpha, KO mice with pancreatitis. It is noteworthy that the PGC-1&alpha, levels lowered in the obese mice livers, which increased the Nos2 mRNA expression and protein nitration levels and decreased energy charge during pancreatitis. In conclusion, obesity impairs PGC-1&alpha, up-regulation in the liver to cause nitrosative stress during acute pancreatitis.

© 2019 Published by Elsevier B.V., Acute pancreatitis is an inflammatory process of the pancreatic gland that may lead to dysregulation of the trans-sulfuration pathway. The aims of this work were firstly to study the methionine cycle as well as the trans-sulfuration pathway using metabolomic and proteomic approaches identifying the causes of this dysregulation in an experimental model of acute pancreatitis; and secondly to reveal the effects of S-adenosylmethionine administration on these pathways. Acute pancreatitis was induced by cerulein in mice, and a group of animals received S-adenosylmethionine treatment. Cerulein-induced acute pancreatitis rapidly caused marked depletion of methionine, S-adenosylmethionine, 5′-methylthioadenosine, cystathionine, cysteine, and glutathione levels in pancreas, but S-adenosylhomocysteine and homocysteine remained unchanged. Protein steady-state levels of S-adenosylhomocysteine-hydrolase and cystathionine gamma-lyase diminished but methylthioadenosine phosphorylase levels increased in pancreas with acute pancreatitis. Although cystathionine β-synthase protein levels did not change with acute pancreatitis, Nos2 mRNA and protein levels were markedly up-regulated and caused tyrosine nitration of cystathionine β-synthase in pancreas. S-adenosylmethionine administration enhanced Nos2 mRNA expression and cystathionine β-synthase nitration and triggered homocysteine accumulation in acute pancreatitis. Furthermore, S-adenosylmethionine administration promoted enrichment of the euchromatin marker H3K4me3 in the promoters of Tnf-α, Il-6, and Nos2 and enhanced the mRNA up-regulation of these genes. Accordingly, S-adenosylmethionine administration increased inflammatory infiltrate and edema in pancreas with acute pancreatitis. In conclusion, tyrosine-nitration of cystathionine β-synthase blockades the trans-sulfuration pathway in acute pancreatitis promoting homocysteine accumulation upon S-adenosylmethionine treatment., This work was supported by Grant SAF2015-71208-R with FEDER funds from the Spanish Ministry of Economy and Competitiveness to J.S.

[Significance]: Nuclear factor kappa B (NF-κB) is a master regulator of the inflammatory response and represents a key regulatory node in the complex inflammatory signaling network. In addition, selective NF-κB transcriptional activity on specific target genes occurs through the control of redox-sensitive NF-κB interactions., [Recent Advances]: The selective NF-κB response is mediated by redox-modulated NF-κB complexes with ribosomal protein S3 (RPS3), Pirin (PIR). cAMP response element-binding (CREB)-binding protein (CBP)/p300, peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC-1α), activator protein-1 (AP-1), signal transducer and activator of transcription 3 (STAT3), early growth response protein 1 (EGR-1), and SP-1. NF-κB is cooperatively coactivated with AP-1, STAT3, EGR-1, and SP-1 during the inflammatory process, whereas NF-κB complexes with CBP/p300 and PGC-1α regulate the expression of antioxidant genes. PGC-1α may act as selective repressor of phospho-p65 toward interleukin-6 (IL-6) in acute inflammation. p65 and nuclear factor erythroid 2-related factor 2 (NRF2) compete for binding to coactivator CBP/p300 playing opposite roles in the regulation of inflammatory genes. S-nitrosylation or tyrosine nitration favors the recruitment of specific NF-κB subunits to κB sites., [Critical Issues]: NF-κB is a redox-sensitive transcription factor that forms specific signaling complexes to regulate selectively the expression of target genes in acute inflammation. Protein–protein interactions with coregulatory proteins, other transcription factors, and chromatin-remodeling proteins provide transcriptional specificity to NF-κB. Furthermore, different NF-κB subunits may form distinct redox-sensitive homo- and heterodimers with distinct affinities for κB sites., [Future Directions]: Further research is required to elucidate the whole NF-κB interactome to fully characterize the complex NF-κB signaling network in redox signaling, inflammation, and cancer., This work was supported by Grant SAF2015–71208-R with FEDER funds from Spanish Ministry of Economy and Competitiveness to J.S. and by network RED2018-102576-T from the Spanish Ministry of Science, Innovation and Universities to J.S. and M.M.

p38α is a redox sensitive MAPK activated by pro-inflammatory cytokines and environmental, genotoxic and endoplasmic reticulum stresses. The aim of this work was to assess whether p38α controls the antioxidant defense in the liver, and if so, to elucidate the mechanism(s) involved and the age-related changes. For this purpose, we used liver-specific p38α-deficient mice at two different ages: young-mice (4 months-old) and old-mice (24 months-old). The liver of young p38α knock-out mice exhibited a decrease in GSH levels and an increase in GSSG/GSH ratio and malondialdehyde levels. However, old mice deficient in p38α had higher hepatic GSH levels and lower GSSG/GSH ratio than young p38α knock-out mice. Liver-specific p38α deficiency triggered a dramatic down-regulation of the mRNAs of the key antioxidant enzymes glutamate cysteine ligase, superoxide dismutase 1, superoxide dismutase 2, and catalase in young mice, which seems mediated by the lack of p65 recruitment to their promoters. Nrf-2 nuclear levels did not change significantly in the liver of young mice upon p38α deficiency, but nuclear levels of phospho-p65 and PGC-1α decreased in these mice. p38α-dependent activation of NF-κB seems to occur through classical IκB Kinase and via ribosomal S6 kinase1 and AKT in young mice. However, unexpectedly the long-term deficiency in p38α triggers a compensatory up-regulation of antioxidant enzymes via NF-κB activation and recruitment of p65 to their promoters. In conclusion, p38α MAPK maintains the expression of antioxidant genes in liver of young animals via NF-κΒ under basal conditions, whereas its long-term deficiency triggers compensatory up-regulation of antioxidant enzymes through NF-κΒ., Graphical abstract fx1, Highlights • The p38α/NF-κB axis maintains the physiological antioxidant defense in the liver. • Long-term deficiency of p38α up-regulates antioxidant enzymes through NF-κΒ. • p38α/NF-κΒ activation in young animals does not up-regulate pro-inflammatory genes.

Resumen: Introducción: La enfermedad de Alzheimer (EA) es la principal enfermedad neurodegenerativa cortical. Su incidencia aumenta con la edad, lo que provoca importantes problemas médicos, sociales y económicos, especialmente en países con población envejecida. Objetivo: El objetivo de esta revisión es poner de manifiesto las evidencias que existen sobre el modo en que la disfunción vascular puede contribuir al deterioro cognitivo en la EA, así como las posibilidades terapéuticas que de ello podrían derivarse. Desarrollo: La hipótesis vascular ha surgido como alternativa a la hipótesis de la cascada amiloide como explicación de la fisiopatología de la EA. Esta hipótesis sitúa en los vasos sanguíneos el origen de una serie de estímulos patogénicos que llevarían a la lesión neuronal y la demencia. La destrucción de la organización de la barrera hematoencefálica, la disminución del flujo sanguíneo cerebral y el establecimiento de un contexto inflamatorio serían responsables de un consecuente daño neuronal a causa de favorecer la agregación del péptido β-amiloide en el cerebro. Las vías que relacionan la disfunción vascular con la neurodegeneración han proporcionado nuevos enfoques terapéuticos y dianas farmacológicas con las que avanzar en la búsqueda de tratamientos para la EA. Conclusiones: Resulta difícil determinar si el componente vascular de la EA es la causa o el efecto de la enfermedad, pero no cabe duda de que la enfermedad vascular tiene una relación importante con la EA. Es probable que la disfunción vascular actúe sinérgicamente con los cambios neurodegenerativos en un ciclo que agrava el deterioro cognitivo propio de la EA. Abstract: Introduction: Alzheimer disease (AD) is the main cortical neurodegenerative disease. The incidence of this disease increases with age, causing significant medical, social and economic problems, especially in countries with ageing populations. Objective: This review aims to highlight existing evidence of how vascular dysfunction may contribute to cognitive impairment in AD, as well as the therapeutic possibilities that might arise from this evidence. Development: The vascular hypothesis emerged as an alternative to the amyloid cascade hypothesis as an explanation for the pathophysiology of AD. This hypothesis locates blood vessels as the origin for a variety of pathogenic pathways that lead to neuronal damage and dementia. Destruction of the organisation of the blood brain barrier, decreased cerebral blood flow, and the establishment of an inflammatory context would thus be responsible for any subsequent neuronal damage since these factors promote aggregation of β-amyloid peptide in the brain. The link between neurodegeneration and vascular dysfunction pathways has provided new drug targets and therapeutic approaches that will add to the treatments for AD. Conclusions: It is difficult to determine whether the vascular component in AD is the cause or the effect of the disease, but there is no doubt that vascular pathology has an important relationship with AD. Vascular dysfunction is likely to act synergistically with neurodegenerative changes in a cycle that exacerbates the cognitive impairment found in AD. Palabras clave: Alzheimer, Neurodegeneración, Péptido β-amiloide, Enfermedad vascular, Flujo sanguíneo cerebral, Barrera hematoencefálica, Keywords: Alzheimer, Neurodegeneration, β-amyloid peptide, Vascular disease, Cerebral blood flow, Blood brain barrier

No-caloric sweeteners, such as aspartame, are widely used in various food and beverages to prevent the increasing rates of obesity and diabetes mellitus, acting as tools in helping control caloric intake. Aspartame is metabolized to phenylalanine, aspartic acid, and methanol. Our aim was to study the effect of chronic administration of aspartame on glutathione redox status and on the trans-sulphuration pathway in mouse liver. Mice were divided into three groups: control; treated daily with aspartame for 90 days; and treated with aspartame plus N-acetylcysteine (NAC). Chronic administration of aspartame increased plasma alanine aminotransferase (ALT) and aspartate aminotransferase activities and caused liver injury as well as marked decreased hepatic levels of reduced glutathione (GSH), oxidized glutathione (GSSG), γ-glutamylcysteine ​​(γ-GC), and most metabolites of the trans-sulphuration pathway, such as cysteine, S-adenosylmethionine (SAM), and S-adenosylhomocysteine ​​(SAH). Aspartame also triggered a decrease in mRNA and protein levels of the catalytic subunit of glutamate cysteine ligase (GCLc) and cystathionine γ-lyase, and in protein levels of methionine adenosyltransferase 1A and 2A. N-acetylcysteine prevented the aspartame-induced liver injury and the increase in plasma ALT activity as well as the decrease in GSH, γ-GC, cysteine, SAM and SAH levels and GCLc protein levels. In conclusion, chronic administration of aspartame caused marked hepatic GSH depletion, which should be ascribed to GCLc down-regulation and decreased cysteine levels. Aspartame triggered blockade of the trans-sulphuration pathway at two steps, cystathionine γ-lyase and methionine adenosyltransferases. NAC restored glutathione levels as well as the impairment of the trans-sulphuration pathway., Highlights • Aspartame down-regulates glutamate cysteine ligase and decreased cysteine levels. • Aspartame blockades the trans-sulphuration pathways.

p38α MAPK negatively regulates the G1/S and G2/M cell cycle transitions. However, liver-specific p38α deficiency impairs cytokinesis and reduces hepatocyte proliferation during cirrhosis and aging in mice. In this work, we have studied how p38α down-regulation affects hepatocyte proliferation after partial hepatectomy, focusing on mitotic progression, cytokinesis and oxidative stress. We found that p38α deficiency triggered up-regulation of cyclins A1, B1, B2, and D1 under basal conditions and after hepatectomy. Moreover, p38α-deficient hepatocytes showed enhanced binucleation and increased levels of phospho-histone H3 but impaired phosphorylation of MNK1 after hepatectomy. The recovery of liver mass was transiently delayed in mice with p38α-deficient hepatocytes vs wild type mice. We also found that p38α deficiency caused glutathione oxidation in the liver, increased plasma aminotransferases and lactate dehydrogenase activities, and decreased plasma protein levels after hepatectomy. Interestingly, p38α silencing in isolated hepatocytes markedly decreased phospho-MNK1 levels, and silencing of either p38α or Mnk1 enhanced binucleation of hepatocytes in culture. In conclusion, p38α deficiency impairs mitotic progression in hepatocytes and restrains the recovery of liver mass after partial hepatectomy. Our results also indicate that p38α regulates cytokinesis by activating MNK1 and redox modulation., A.M.T. was recipient of a fellowship from the Ministry of Economy and Competitiveness. This work was supported by Grants SAF 2015-71208-R with FEDER funds and CSD-2007-00020 from the Spanish Ministry of Economy and Competitiveness (MINECO, Spain, http://www.mineco.gob.es/portal/site/mineco/) and GV PROMETEO II 2014-056 from Generalitat Valenciana to J.S. and R.T.V., and by Grant SAF 2015- 65267-R (MINECO/FEDER) and by Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERdem, ISCIII, Spain) to A.M.V.

Background Optimisation of tissue processing procedures in preclinical studies reduces the number of animals used and allows integrated multilevel study in the same sample. Multiple extraction of different biomolecules from the same sample has several limitations. New method Using brain samples from rats subjected to ischemic stroke, we combined lyophilisation of flash-frozen tissue, mechanical pulverisation and cryopreservation in a method to optimise tissue handling and preservation for independent RNA or protein single-extract methods, and subsequent RT-qPCR or Western blot analyses. Results Lyophilisation resulted in 70% tissue weight loss. RNA (OD260/280∼1.8) and protein yields were similar in non-ischemic and ischemic brain samples, subjected to either flash freezing (FF) or flash freezing followed by lyophilisation (FF + Lyo). RNA transcription of reference genes (Actb and Rn18s), expression of housekeeping proteins (β-actin and α-tubulin), and mRNA overexpression of stroke-regulated genes (Nos2, Mmp9 and Tnfa) was similar in FF and FF + Lyo samples. Comparison with existing method(s) Contrary to high heat stress of baking method in a drying oven, lyophilisation maintains the integrity of dried samples for subsequent extractions and analyses. Sample lyophilisation allows different manual representative extractions/analyses from the same rat, it is much cheaper than using commercial kits, and shows higher yields that multiple manual or kit-based extractions. Conclusions The lyophilisation-based method for different biomolecule single-extractions from tissue powder aliquots, representing the same rat brain sample, is sample saving, contributes to the reduction principle in animal research, and allows coordinated analysis for accurate correlations between the transcriptome and proteome in stroke and other neuroscience research.

Introduction: Alzheimer disease (AD) is the main cortical neurodegenerative disease. The incidence of this disease increases with age, causing significant medical, social and economic problems, especially in countries with ageing populations. Objective: This review aims to highlight existing evidence of how vascular dysfunction may contribute to cognitive impairment in AD, as well as the therapeutic possibilities that might arise from this evidence. Development: The vascular hypothesis emerged as an alternative to the amyloid cascade hypothesis as an explanation for the pathophysiology of AD. This hypothesis locates blood vessels as the origin for a variety of pathogenic pathways that lead to neuronal damage and dementia. Destruction of the organisation of the blood–brain barrier, decreased cerebral blood flow, and the establishment of an inflammatory context would thus be responsible for any subsequent neuronal damage since these factors promote aggregation of β-amyloid peptide in the brain. The link between neurodegeneration and vascular dysfunction pathways has provided new drug targets and therapeutic approaches that will add to the treatments for AD. Conclusions: It is difficult to determine whether the vascular component in AD is the cause or the effect of the disease, but there is no doubt that vascular pathology has an important relationship with AD. Vascular dysfunction is likely to act synergistically with neurodegenerative changes in a cycle that exacerbates the cognitive impairment found in AD. Resumen: Introducción: La enfermedad de Alzheimer (EA) es la principal enfermedad neurodegenerativa cortical. Su incidencia aumenta con la edad, lo que provoca importantes problemas médicos, sociales y económicos, especialmente en países con población envejecida. Objetivo: El objetivo de esta revisión es poner de manifiesto las evidencias que existen sobre el modo en que la disfunción vascular puede contribuir al deterioro cognitivo en la EA, así como las posibilidades terapéuticas que de ello podrían derivarse. Desarrollo: La hipótesis vascular ha surgido como alternativa a la hipótesis de la cascada amiloide como explicación de la fisiopatología de la EA. Esta hipótesis sitúa en los vasos sanguíneos el origen de una serie de estímulos patogénicos que llevarían a la lesión neuronal y la demencia. La destrucción de la organización de la barrera hematoencefálica, la disminución del flujo sanguíneo cerebral y el establecimiento de un contexto inflamatorio serían responsables de un consecuente daño neuronal a causa de favorecer la agregación del péptido β-amiloide en el cerebro. Las vías que relacionan la disfunción vascular con la neurodegeneración han proporcionado nuevos enfoques terapéuticos y dianas farmacológicas con las que avanzar en la búsqueda de tratamientos para la EA. Conclusiones: Resulta difícil determinar si el componente vascular de la EA es la causa o el efecto de la enfermedad, pero no cabe duda de que la enfermedad vascular tiene una relación importante con la EA. Es probable que la disfunción vascular actúe sinérgicamente con los cambios neurodegenerativos en un ciclo que agrava el deterioro cognitivo propio de la EA. Keywords: Alzheimer, Neurodegeneration, β-Amyloid peptide, Vascular disease, Cerebral blood flow, Blood–brain barrier, Palabras clave: Alzheimer, Neurodegeneración, Péptido β-amiloide, Enfermedad vascular, Flujo sanguíneo cerebral, Barrera hematoencefálica

[Background]: Hepatocyte poliploidization is an age-dependent process, being cytokinesis failure the main mechanism of polyploid hepatocyte formation. Our aim was to study the role of p38α MAPK in the regulation of actin cytoskeleton and cytokinesis in hepatocytes during development and aging. [Methods]: Wild type and p38α liver-specific knock out mice at different ages (after weaning, adults and old) were used. [Results]: We show that p38α MAPK deficiency induces actin disassembly upon aging and also cytokinesis failure leading to enhanced binucleation. Although the steady state levels of cyclin D1 in wild type and p38α knock out old livers remained unaffected, cyclin B1- a marker for G2/M transition- was significantly overexpressed in p38α knock out mice. Our findings suggest that hepatocytes do enter into S phase but they do not complete cell division upon p38α deficiency leading to cytokinesis failure and binucleation. Moreover, old liver-specific p38α MAPK knock out mice exhibited reduced F-actin polymerization and a dramatic loss of actin cytoskeleton. This was associated with abnormal hyperactivation of RhoA and Cdc42 GTPases. Long-term p38α deficiency drives to inactivation of HSP27, which seems to account for the impairment in actin cytoskeleton as Hsp27-silencing decreased the number and length of actin filaments in isolated hepatocytes. [Conclusions]: p38α MAPK is essential for actin dynamics with age in hepatocytes., AMT was recipient of a fellowship from the Ministry of Economy and Competitiveness. PR was recipient of a postdoctoral contract Juan de la Cierva (MINECO, Spain). This work was supported by Grants SAF 2015-71208-R with FEDER funds and CSD-2007-00020 from the Spanish Ministry of Economy and Competitiveness (MINECO, Spain, http://www.mineco.gob.es/portal/site/mineco/) and GV PROMETEO II 2014-056 from Generalitat Valenciana to JS and RTV, and by Grant SAF 2015-65267-R (MINECO/FEDER) and by Centro de Investigación Biomédica en Red de Diabetes y Enfermedades Metabólicas Asociadas (CIBERDEM, ISCIII, Spain) to AMV. ARN was funded by grants from MINECO (BFU2010-17850) and the European Commission (ERC 294665).

Redox signaling regulates physiological self-renewal, proliferation, migration and differentiation in gastrointestinal epithelium by modulating Wnt/β-catenin and Notch signaling pathways mainly through NADPH oxidases (NOXs). In the intestine, intracellular and extracellular thiol redox status modulates the proliferative potential of epithelial cells. Furthermore, commensal bacteria contribute to intestine epithelial homeostasis through NOX1- and dual oxidase 2-derived reactive oxygen species (ROS). The loss of redox homeostasis is involved in the pathogenesis and development of a wide diversity of gastrointestinal disorders, such as Barrett's esophagus, esophageal adenocarcinoma, peptic ulcer, gastric cancer, ischemic intestinal injury, celiac disease, inflammatory bowel disease and colorectal cancer. The overproduction of superoxide anion together with inactivation of superoxide dismutase are involved in the pathogenesis of Barrett's esophagus and its transformation to adenocarcinoma. In Helicobacter pylori-induced peptic ulcer, oxidative stress derived from the leukocyte infiltrate and NOX1 aggravates mucosal damage, especially in HspB+ strains that downregulate Nrf2. In celiac disease, oxidative stress mediates most of the cytotoxic effects induced by gluten peptides and increases transglutaminase levels, whereas nitrosative stress contributes to the impairment of tight junctions. Progression of inflammatory bowel disease relies on the balance between pro-inflammatory redox-sensitive pathways, such as NLRP3 inflammasome and NF-κB, and the adaptive up-regulation of Mn superoxide dismutase and glutathione peroxidase 2. In colorectal cancer, redox signaling exhibits two Janus faces: On the one hand, NOX1 up-regulation and derived hydrogen peroxide enhance Wnt/β-catenin and Notch proliferating pathways; on the other hand, ROS may disrupt tumor progression through different pro-apoptotic mechanisms. In conclusion, redox signaling plays a critical role in the physiology and pathophysiology of gastrointestinal tract.

Disulfide stress has been associated with inflammation and characterized by an increase in cystine levels and protein cysteinylation. Furthermore, it was recently discovered that thioredoxin-related protein of 14 kDa (TRP14, encoded by TXNDC17) exhibits efficient cystine reductase activity. The aim of our research was to elucidate if TRP14 is also able to reduce cysteinylated proteins in mammalian cells. Thus, protein cysteinylation was assessed in control and TRP14 knockdown cells in vitro through their pre-treatment with 25 µg/ml cycloheximide for 30 min and incubation with 250 µM biotinylated cysteine for 1 h. Moreover, such TRP14 knockdown cell lysates were tested as cysteinylated substrates for TRP14 activity through their incubation with 20 µM human TRP14, 1 uM thioredoxin reductase 1 (TrxR1) and 1 mM NADPH for 15 min at 25oC. TRP14 knockdown cells showed more protein cysteinylation than control cells. Human TRP14, in a reaction together with TrxR1 and NADPH, could also reduce cysteinylated protein substrates in cell lysates. In conclusion, TRP14 is able to directly reduce protein cysteinylation motifs. The potential in vivo significance of this enzymatic activity awaits further clarification.

Acute pancreatitis (AP) is an acute inflammatory process of the pancreatic gland. The aim of this work was to evaluate the role of thiol oxidation of key proteins that can be involved in the regulation of the inflammatory process during AP. AP was induced in C57BL/6 mice by 7 hourly subcutaneous injections of cerulein (50 ug/kg bw). Animals were sacrificed after 1, 3, 5 and 7 injections of cerulein. One hour after the first injection, hyperoxidation of peroxiredoxin 1–4 was detected coinciding with a H2O2 peak. Three hours later, a marked up-regulation of mRNA and protein expression of sulfiredoxin, partially mediated by Nrf-2, takes place. The up-regulation of sulfiredoxin seems to be responsible for the decrease in hyperoxidation of peroxiredoxin 1–4 to allow Prdx1 and Prdx2 reduce H2O2 production in the middle phase of AP induction. During the induction of AP we have detected an overoxidation of protein phosphatases PP2A and SHP2. Inactivation of PP2A and SHP2 during acute pancreatitis by intramolecular disulphide bridges would be favour the early activation of MAPKs JNK, ERK1/2 and p38. Therefore, we conclude that modulation of the redox state of PP2A and SHP2 and peroxiredoxins by sulfiredoxin may play a key role in the up-regulation of the inflammatory cascade.

p38α MAPK is a sensor of oxidative stress. The aim of this work was to assess the role of p38α in the regulation of the antioxidant defense in the liver with aging. Livers ofyoung and old wild type (WT) and p38α liver-specific knock out (KO) mice were used to determine glutathione redox status by mass spectrometry; malondialdehyde (MDA) levels by HPLC; mRNA expression of glutamate cysteine ligase (Gclc), Sod1, Sod2 and catalase by RT-PCR and nuclear levels of NF-κB subunit p65 by western-blotting. Chromatin immunoprecipitation (ChIP) assay of p65 was performed. Young KO liver exhibited increased in GSSG/GSH ratio and MDA levels when are compared with young WT mice. However, old KO mice had lower hepatic GSSG/GSH ratio and MDA levels than young KO mice. The mRNA expression of Gclc, Sod1, Sod2 and catalase was decreased in young KO mice compared with WT young mice. In contrast, these antioxidant enzymes were up-regulated in KO old mice regard to WT. p65 was markedly phosphorylated in the nucleus of WT young and old KO mice. ChIP assay of p65 confirmed the recruitment of p65 to the promoters of antioxidant genes in WT young and KO old mice. Deficiency of p38α in the liver causes dramatic down-regulation of antioxidant enzymes in young mice, but triggers adaptive up-regulation in the long term via NF-κB to enhance the antioxidant defense in old p38α KO mice.

Obesity is associated with local and systemic complications in acute pancreatitis. PPARγ coactivator 1α (PGC-1α) is a transcriptional coactivator and master regulator of mitochondrial biogenesis that exhibits dysregulation in obese subjects. Our aims were: (1) to study PGC-1α levels in pancreas from lean or obese rats and mice with acute pancreatitis; and (2) to determine the role of PGC-1α in the inflammatory response during acute pancreatitis elucidating the signaling pathways regulated by PGC-1α. Lean and obese Zucker rats and lean and obese C57BL6 mice were used first; subsequently, wild-type and PGC-1α knockout (KO) mice with cerulein-induced pancreatitis were used to assess the inflammatory response and expression of target genes. Ppargc1a mRNA and protein levels were markedly downregulated in pancreas of obese rats and mice versus lean animals. PGC-1α protein levels increased in pancreas of lean mice with acute pancreatitis, but not in obese mice with pancreatitis. Interleukin-6 (Il6) mRNA levels were dramatically upregulated in pancreas of PGC-1α KO mice after cerulein-induced pancreatitis in comparison with wild-type mice with pancreatitis. Edema and the inflammatory infiltrate were more intense in pancreas from PGC-1α KO mice than in wild-type mice. The lack of PGC-1α markedly enhanced nuclear translocation of phospho-p65 and recruitment of p65 to Il6 promoter. PGC-1α bound phospho-p65 in pancreas during pancreatitis in wild-type mice. Glutathione depletion in cerulein-induced pancreatitis was more severe in KO mice than in wild-type mice. PGC-1α KO mice with pancreatitis, but not wild-type mice, exhibited increased myeloperoxidase activity in the lungs, together with alveolar wall thickening and collapse, which were abrogated by blockade of the IL-6 receptor glycoprotein 130 with LMT-28. In conclusion, obese rodents exhibit PGC-1α deficiency in the pancreas. PGC-1α acts as selective repressor of nuclear factor-κB (NF-κB) towards IL-6 in pancreas. PGC-1α deficiency markedly enhanced NF-κB-mediated upregulation of Il6 in pancreas in pancreatitis, leading to a severe inflammatory response., This work was supported by grants SAF2009‐09500 and SAF2015–71208‐R with FEDER funds from the Spanish Ministry of Economy and Competitiveness to JS and by grants SAF2015‐63904‐R with FEDER funds from the Spanish Ministry of Economy and Competitiveness and EC MSCA‐ITN‐2016‐721236 to MM. IF was recipient of a fellowship from ‘Programa de Pós‐Doutorado no Exterior (PDE)’ that belongs to the ‘Conselho Nacional de Desenvolvimento Científico e Tecnológico’ (CNPq).