Quantitative proteomic analysis of age-related subventricular zone proteins associated with neurodegenerative disease.

Aging is characterized by a progressive decline in the function of adult tissues which can lead to neurodegenerative disorders. However, little is known about the correlation between protein changes in the subventricular zone (SVZ) and neurodegenerative diseases with age. In the present study, neural stem cells (NSCs) were derived from the SVZ on postnatal 7 d, 1 m, and 12 m-old mice. With age, NSCs exhibited increased SA-β-gal activity and decreased proliferation and pool size in the SVZ zone, and were associated with elevated inflammatory chemokines and cytokines. Furthermore, quantitative proteomics and ingenuity pathway analysis were used to evaluate the significant age-related alterations in proteins and their functions. Some downregulated proteins such as DPYSL2, TPI1, ALDH, and UCHL1 were found to play critical roles in the neurological disease and PSMA1, PSMA3, PSMC2, PSMD11, and UCHL1 in protein homeostasis. Taken together, we have provided valuable insight into the cellular and molecular processes that underlie aging-associated declines in SVZ neurogenesis for the early detection of differences in gene expression and the potential risk of neurological disease, which is beneficial in the prevention of the diseases

Exposed Hydrophobic Residues in Human Immunodeficiency Virus Type 1 Vpr Helix-1 Are Important for Cell Cycle Arrest and Cell Death

The human immunodeficiency virus type 1 (HIV-1) accessory protein viral protein R (Vpr) is a major determinant for virus-induced G2/M cell cycle arrest and cytopathicity. Vpr is thought to perform these functions through the interaction with partner proteins. The NMR structure of Vpr revealed solvent exposed hydrophobic amino acids along helices 1 and 3 of Vpr, which could be putative protein binding domains. We previously showed that the hydrophobic patch along helix-3 was important for G2/M blockade and cytopathicity. Mutations of the exposed hydrophobic residues along helix-1 were found to reduce Vpr-induced cell cycle arrest and cell death as well. The levels of toxicity during virion delivery of Vpr correlated with G2/M arrest. Thus, the exposed hydrophobic amino acids in the amino-terminal helix-1 are important for the cell cycle arrest and cytopathicity functions of Vpr

Attenuated Inflammatory Response in Aged Mice Brains following Stroke

Background: Increased age is a major risk factor for stroke incidence, post-ischemic mortality, and severe and long-term disability. Stroke outcome is considerably influenced by post-ischemic mechanisms. We hypothesized that the inflammatory response following an ischemic injury is altered in aged organisms. Methods and Results: To that end, we analyzed the expression pattern of pro-inflammatory cytokines (TNF, IL-1a, IL-1b, IL-6), anti-inflammatory cytokines (IL-10, TGFb1), and chemokines (Mip-1a, MCP-1, RANTES) of adult (2 months) and aged (24 months) mice brains at different reperfusion times (6 h, 12 h, 24 h, 2 d, 7 d) following transient occlusion of the middle cerebral artery. The infarct size was assessed to monitor possible consequences of an altered inflammatory response in aged mice. Our data revealed an increased neuro-inflammation with age. Above all, we found profound age-related alterations in the reaction to stroke. The response of pro-inflammatory cytokines (TNF, and IL-1b) and the level of chemokines (Mip-1a, and MCP-1) were strongly diminished in the aged post-ischemic brain tissue. IL-6 showed the strongest age-dependent decrease in its post-ischemic expression profile. Anti-inflammatory cytokines (TGFb1, and IL-10) revealed no significant age dependency after ischemia. Aged mice brains tend to develop smaller infarcts. Conclusion: The attenuated inflammatory response to stroke in aged animals may contribute to their smaller infarcts. The results presented here highlight the importance of using aged animals to investigate age-associated diseases like stroke

Análisis de la endotoxemia en el postoperatorio de cirugía cardiaca

Desde el inicio de la cirugía cardiaca, el desarrollo de nuevas técnicas quirúrgicas, los avances en los métodos de circulación extracorpórea (CEC) y los tratamientos en cuidados intensivos hacen que la mortalidad de estos pacientes haya disminuido de casi el 100% hasta un 5-6% en la actualidad. No obstante, estas cifras se mantienen estables durante los últimos años. La respuesta inflamatoria asociada a la CEC es un proceso que puede llegar a desarrollar complicaciones mayores incluyendo insuficiencia respiratoria, shock, fracaso renal e incluso fracaso multiorgánico. La cirugía con CEC provoca cambios sistémicos importantes que inician el proceso de SIRS. Entre ellos se encuentra la hipoperfusión esplénica, que podría producir daños en la mucosa intestinal alterando la permeabilidad de la barrera favoreciendo así la traslocación bacteriana y la endotoxemia. La endotoxina es un lipopolisacárido de la pared celular de las BGN y es reconocido como un importante estímulo para el desarrollo del SIRS. Su presencia en pacientes sometidos a CEC ha sido ampliamente reconocida, pero la magnitud de la endotoxemia así como su correlación con la evolución clínica y la aparición de complicaciones varía ampliamente entre los estudios. Según algunos estudios, la concentración sistémica de endotoxinas se correlaciona estrechamente con el grado de disfunción cardiovascular, duración de la cirugía, tiempo de CEC, tiempo de isquemia y necesidad de aminas vasoactivas, lo que se podría resumir en todas aquellas situaciones que potencialmente podrían favorecer una situación de hipopefusión esplácnica. Existen diferentes técnicas para detectar la presencia de la endotoxemia. Tradicionalmente, se había cuantificado la cantidad de endotoxina mediante un análisis in vitro denominado lisado de Amebocitos del Limulus Polyphemus (LAL), pero este test nunca ha sido aprobado por la FDA pasa su uso en sangre. Esto ha motivado el descubrimiento de un nuevo test llamado ensayo de actividad de endotoxina (EAA) (Spectral Diagnostics, Toronto, ON, Canadá), que consta de un kit de prueba rápida de quimioluminiscencia inmunodiagnóstica que se puede realizar en menos de 1 hora, aprobado por la FDA para su realización en líquidos biológicos como es la sangre. Los objetivos marcados del estudio fueron detectar la presencia de endotoxemia en el postoperatorio de cirugía cardiaca utilizando un nuevo método diagnóstico así como establecer los factores de riesgo de presentar endotoxemia y establecer la implicación pronóstica de esta. El estudio se ha realizado en la Unidad de Cuidados Intensivos del Hospital Germans Trías i Pujol, Badalona. Incluimos un total de 107 pacientes, la mayoría varones (69%), con una edad media de 66 años (36-87). El 38% tenían DM, 71% HTA y un 12% vasculopatía periférica. La mediana del EuroSCORE I fue de 7 (0-16). Solo 24 pacientes presentaron endotoxemia alta (≥0,4EA). La duración mediana de la CEC fue de 95 min (24-300) con un tiempo de isquemia (ClAo) de 72 min (17-175). El 37% de los pacientes requirieron transfusión de concentrados de hematíes. Los resultados de nuestro estudio indican que en el postoperatorio de cirugía cardiaca existe endotoxemia al menos en grado moderado y que esta puede tener utilidad en la detección de aquellos pacientes que pueden presentar infección postoperatoria precoz. Como factor de riesgo de endotoxemia, hemos observado que aquellos pacientes con vasculopatía periférica y los que requieren trasfusión de mayor cantidad de concentrados de hematíes durante la intervención son los que presentan mayor riesgo de presentar endotoxemia en el postoperatorio inmediato.Since the beginning of cardiac surgery, development of new surgical techniques, advances in methods of cardiopulmonary bypass (CPB) and intensive care treatments, mortality has decreased from almost 100% to 5- 6% today. However, these figures have remained stable in recent years. The inflammatory response to CPB has been implicated in many of the postoperative clinical problems that often occur in these patients including respiratory failure, postoperative shock states, renal failure and multiple organ dysfunction syndrome. These systemic changes may be due to many different mechanisms. One mechanism, is attributed to splanchnic hypoperfusion that might cause harm to the intestinal mucosa by altering the barrier's permeability, thus favouring bacterial translocation and endotoxemia. Endotoxin is a lipopolysaccharide in the membrane of GNB and is known to be one of the most potent activators known of innate immunity and the inflammatory response in humans. In patients subjected to cardiac surgery, transient endotoxemia has been shown in many occasions, which seems to be closely related to extracorporeal circulation, but the magnitude of endotoxemia and their correlation with clinical evolution and the development of complications vary widely between studies. According to some studies, systemic endotoxin concentration is closely correlated with the degree of cardiovascular dysfunction, duration of CPB, ischemic time and need for vasoactive amines, which can be summarized in all situations that could potentially favor a situation of splanchnic hypoperfusion. There are different techniques to detect the presence of endotoxemia. The amount of endotoxin has traditionally been quantified by the analysis known as "Limulus amebocyte lysate" (LAL), but this test has never been approved by the FDA for clinical use in humans. This has led to the discovery of a new test called endotoxin activity assay (EAA) (Spectral Diagnostics, Toronto, ON, Canada), comprising a rapid chemiluminiscent immunodiagnostic test kit that can be performed in less than 1 hour, approved by the FDA for its realization in biological fluids such as it is blood. The purpose of the study was to assess the prevalence of endotoxemia related to CPB in a cohort of patients undergoing cardiac surgery, using the EAA test. There was also investigated the criteria for high risk of endotoxemia and the association between endotoxemia and the development of adverse clinical events including length of stay and mortality. The study was performed in the Intensive Care Unit of Germans Trias i Pujol Hospital, in Badalona. A total of 107 patients were enrolled. Of these 107 patients, the median age was 66 years (36-87), most were males (69%), 38% had DM, 71% HTA and 12% peripheral vascular disease. Median EuroSCORE I was 7 (0-6). Only 23 patients had EAA ≥0,4 EA. Median CBP time was 95 (24-300) and isquemic time 68 (17-175) minutes. 37% required blood transfusion. The results of the study indicate that in postoperative cardiac surgery there is endotoxemia at least in moderate degree, and that the presence of endotoxemia is significantly related to early postoperative infection. As a risk factor, we found that patients with peripheral vascular disease and transfused more than 2 during surgery are those with increased risk of endotoxemia