GQ-16, a novel peroxisome proliferator-activated receptor (PPAR ) ligand, promotes insulin sensitization without weight gain

ABSTRACTBackground: PPAR agonists improve insulin sensitivity but also evoke weight gain. Results: GQ-16 is a PPAR partial agonist that blocks receptor phosphorylation by Cdk5 and improves insulin sensitivity in diabetic mice in the absence of weight gain. Conclusion: The unique binding mode of GQ-16 appears to be responsible for the compound’s advantageous pharmacological profile. Significance: Similar compounds could have promise as anti-diabetic therapeutics

Radiation-Induced c-Jun Activation Depends on MEK1-ERK1/2 Signaling Pathway in Microglial Cells

Radiation-induced normal brain injury is associated with acute and/or chronic inflammatory responses, and has been a major concern in radiotherapy. Recent studies suggest that microglial activation is a potential contributor to chronic inflammatory responses following irradiation; however, the molecular mechanism underlying the response of microglia to radiation is poorly understood. c-Jun, a component of AP-1 transcription factors, potentially regulates neural cell death and neuroinflammation. We observed a rapid increase in phosphorylation of N-terminal c-Jun (on serine 63 and 73) and MAPK kinases ERK1/2, but not JNKs, in irradiated murine microglial BV2 cells. Radiation-induced c-Jun phosphorylation is dependent on the canonical MEK-ERK signaling pathway and required for both ERK1 and ERK2 function. ERK1/2 directly interact with c-Jun in vitro and in cells; meanwhile, the JNK binding domain on c-Jun is not required for its interaction with ERK kinases. Radiation-induced reactive oxygen species (ROS) potentially contribute to c-Jun phosphorylation through activating the ERK pathway. Radiation stimulates c-Jun transcriptional activity and upregulates c-Jun-regulated proinflammatory genes, such as tumor necrosis factor-α, interleukin-1β, and cyclooxygenase-2. Pharmacologic blockade of the ERK signaling pathway interferes with c-Jun activity and inhibits radiation-stimulated expression of c-Jun target genes. Overall, our study reveals that the MEK-ERK1/2 signaling pathway, but not the JNK pathway, contributes to the c-Jun-dependent microglial inflammatory response following irradiation

Precocidade do comanejo clínico-cirurgico associada a melhores desfechos em um hospital público terciário brasileiro

Introdução: O modelo de cuidado denominado Comanejo Clínico-Cirúrgico baseia-se no cuidado compartilhado de pacientes cirúrgicos entre clínicos e cirurgiões. Ele vem sendo cada vez mais adotado em hospitais com enfermarias cirúrgicas. Diversos estudos nesse tema demonstram associação com melhorias assistenciais desta população. Método: Estudo de coorte histórica de pacientes em comanejo clínico-cirúrgico em um hospital público terciário de ensino do Brasil. Os desfechos avaliados foram mortalidade hospitalar e complicações graves pós-operatórias, utilizando o tempo até o início do comanejo como uma das variáveis em modelos de regressão multivariável de Poisson. Resultados: De setembro de 2014 a setembro de 2016, foram atendidos 443 pacientes. A idade média foi 64,6 (+14,6), as taxas de mortalidade e complicações graves foram 23,5% e 41,6%, respectivamente, e o tempo médio de internação foi de 35 dias. As áreas com mais comanejos realizados foram a Cirurgia Geral (146, 33%), a Urologia, (91, 20,5%) e a Ginecologia/Obstetrícia (51, 11,5%). As condições que demandaram comanejo com maior frequência foram: infecção hospitalar, 149 casos (33,6%), distúrbios hidroeletrolíticos, 132 (29,8%) e disfunção ventilatória, 65 (14,7%). As condições que mais geraram encaminhamentos à UTI foram infecção hospitalar, 30 casos (20,1%), distúrbios hidroeletrolíticos, 19 (14,5%), e congestão volêmica, 16 (20,8%). Nos modelos de regressão Poisson, os preditores de mortalidade no modelo ajustado foram o escore de Charlson (RR 1,16 [IC 95% 1,12-1,21; P<0,001]) e o tempo 8 internação-comanejo (RR 1,04 [IC 95% 1,01-1,08; P=0,010]). Para complicação grave pós-operatória, as variáveis foram choque séptico pré-operatório (RR 1,81 [IC 95% 1,43-2,30; P <0,001]), sangramento pré-operatório com necessidade de transfusão (RR 1,70 [IC 95% 1,162-2,49; P=0,006]), creatinina pré-operatória (RR 1,08 [IC 95% 1,02-1,14; P=0,006]), tempo internação-comanejo (RR 1,04 [IC 95% 1,03-1,06 ;P<0,001]) e duração da cirurgia (RR 1,09 [IC 95% 1,03-1,16; P=0,003]). Conclusão: Um modelo de comanejo baseado em um sistema de consultorias pelas equipes assistentes demonstrou inclusão de pacientes graves, complexos e com pior prognóstico. O início precoce do comanejo foi um fator protetor tanto de mortalidade hospitalar quanto de complicações graves pós-operatórias, o que reforça a necessidade da avaliação sistemática desses pacientes em enfermarias cirúrgicas no momento da sua entrada no serviço.Introduction: The model of care called Surgical Comanagement is based on the shared care of surgical patients between clinicians and surgeons. It has been increasingly adopted in hospitals with surgical nurseries. Several studies in the area have shown an association with improvements in the care of this population. Method: Historical cohort study of patients in surgical comanagement in public tertiary teaching hospital in Brazil. The outcomes measured were hospital mortality and severe postoperative complications, using time for start of surgical comanagement as one of the variables in multivariate Poisson regression models. Results: From September 2014 to September 2016 (2 years), 443 patients were cared. The mean age was 64.6 (±14.6), while the taxes of mortality and severe complications were 23.5% and 41.6%, respectively, and the mean length of hospital stay was 35 days. The areas with the greatest number of comanagements were General Surgery (146, 33%), Urology, (91, 20.5%) and Gynecology / Obstetrics (51, 11.5%). The conditions that demanded comanagement with the most frequency were: hospital infection, 149 cases (33.6%), hydroelectrolytic disorders, 132 (29.8%) and ventilatory dysfunction, 65 (14.7%). The conditions that were most transfered to the ICU were hospital infection, 30 cases (20.1%), hydroelectrolytic disorders, 19 (14.5%), and volume overload, 16 (20.8%). In the Poisson regression models, the mortality predictors after adjustment were the Charlson score (RR 1,16 [95% CI 1,11-1,21; P <0.001]) and time from hospitalization to comanagement (RR 1.04 [95% CI 1.01-1.08 ; P = 0.010]). Severe postoperative complications predictors were preoperative septic shock (RR 1.81 11 [95% CI 1.43-2.30, P <0.001]), preoperative bleeding requiring transfusion (RR 1.70 [95% CI] 1,16-2,49]). ; P = 0.006]), preoperative creatinine (RR 1.08 [95% CI 1.02-1.14, P = 0.006]), time for surgical comanagement starting (HR 1.04 [95% CI 1.03-1.06, P <0.001)) and duration of surgery (RR 1.09 [95% CI 1.03-1.16; P = 0.003]). Conclusion: A comanagement model based on a consultation system managed by the care teams showed that the patients selected were the most severe, complex and with a worse prognosis. Early initiation of comanagement was a predictor of hospital death and severe postoperative complications, which reinforces the need of a systematical evaluation of all patients in surgery ward from the time of your entrance in the nursery

Radiation-induced phosphorylation of c-Jun modulates its transcriptional activity.

<p>(A) Radiation-increased AP-1 DNA binding ability was reduced by MEK kinase inhibitor U0126. To determine the effect of U0126 on c-Jun DNA binding ability, different nuclear extracts as indicated were incubated with the γ-³²p-labeled AP-1 consensus DNA probe. 5% acrylamide gel (0.5× TBE) was used to resolve the products of the binding reaction. Binding specificity is shown by the reaction only with BSA and competition with 50-fold excess non-radioactive consensus AP-1 oligonucleotide (cold AP-1 oligo). (B) BV2 cells were irradiated with 10 Gy dose with or without U0126. Cells were collected at the indicated time points and subsequently used to detect the expression of c-Jun target genes. Protein levels of COX-2 and cyclin D1 were examined by Western blot and transcription levels of TNFα, IL-1β, and IL-6 were examined by RT-PCR. (C) Real-time PCR was used to quantitatively analyze the expression of TNFα, IL-1β, and IL-6. Data represent mean ± SD, *<i>p</i><0.05; **<i>p</i><0.01.</p

Radiation-induced phosphorylation of c-Jun and ERK1/2 in BV2 cells.

<p>(A) BV2 cells were irradiated with a single dose of 10 Gy, and sampled at the time points indicated. Cell lysates were sequentially immunoblotted with indicated antibodies in Western blot assays to detect phosphorylated and total proteins of c-Jun, ERK1/2, and JNK. β-actin was used as a loading control. Increased phosphorylation was found for c-Jun and ERK1/2 post irradiation, but not for JNKs. There was no obvious change for total c-Jun. The right panel shows the fold change for phosphorylation of c-Jun (Ser63 and Ser73) and ERK1/2 following irradiation. Data represent mean ± SD and the significant differences compared to control were indicated as *<i>p</i><0.05 or **<i>p</i><0.01. (B) BV2 cells were irradiated with different doses as shown and phosphorylation of c-Jun and ERK1/2 was detected at 0.5 and 1 h post-irradiation. Regardless of dose levels, radiation markedly stimulated phosphorylation of c-Jun and ERK1/2.</p

JNK function on c-Jun phosphorylation in BV2 cells.

<p>BV2 cells were individually treated with U0126 (10 μM) and the JNK inhibitor SP600125 (5 μM). Cells were irradiated (10 Gy) or sham-irradiated. Cell lysates were collected 1 h post-irradiation. (A) Levels of p-c-Jun and p-ERK1/2 in the treated cells. (B) Levels of c-Jun, ERK, p-JNKs, and JNKs in the treated cells.</p

MEK-ERK1/2 signaling pathway is required for radiation-induced c-Jun phosphorylation.

<p>(A) Cell lysates collected from 10 Gy-irradiated BV2 cells were immunoblotted with anti-phosphorylated MEK1/2 (sc-7995R) antibody. (B) BV2 cells were transfected with HA-MEK1, HA-MEK1^K97M (kinase-dead mutant), and vector control. Protein levels of p-c-Jun and p-ERK1/2 (upper and lower panels) are shown. (C) BV2 cells that were treated or untreated with 10 μM U0126 were irradiated with 10 Gy. p-c-Jun and p-ERK1/2 levels were analyzed by Western blot. (D) Two shRNAs (sh-MEK1-212 and sh-MEK1-495) were lentivirally delivered into BV2 cells to knockdown MEK1 protein. Knockdown efficiency and protein levels of p-c-Jun and p-ERK1/2 were detected with the indicated antibodies. The quantification results for (C) and (D) are shown in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0036739#pone.0036739.s002" target="_blank">Figure S2</a>.</p

ERK1 and ERK2 are indispensable for radiation-induced c-Jun phosphorylation in BV2 cells.

<p>(A) BV2 cells were transiently cotransfected with ERK1 and ERK2 expression vectors in doses of 75, 150 and 300 ng for each plasmid. The total DNA amounts in transfection were compensated with an empty vector. The transfected ERK1 and ERK2 led to a dose-dependent increase of phosphorylated ERK1/2 and c-Jun. (B) BV2 cells were treated with 10 µM ERK kinase inhibitor (Calbiochem Cat #328006) and DMSO as a control. Inhibitor-treated or untreated cells were collected at 1 h after 10 Gy irradiation. Western blots showed that ERK kinase inhibitor abolished radiation-stimulated phosphorylation of ERK1/2 and c-Jun. (C) To detect knockdown effects for ERK1 and ERK2 by lentiviral shRNA constructs in BV2 cells, two lentivirual shRNAs were prepared for each ERK kinase, respectively, and used for infecting BV2 cells. The cells were collected 48 h after lentiviral infection and subjected for Western blot analysis using the antibody against ERK1 (K32, sc-94), which also can recognize ERK2. Efficient depletion was found in the cell lysates infected with sh-ERK1-974, sh-ERK2-321, and sh-ERK2-772, but not sh-ERK1-536. (D) BV2 cells were individually infected with scrambled control, ERK1, and ERK2 shRNA lentiviruses, and subsequently irradiated with 10 Gy 48 h post infection and sampled at 1 h following radiation. There was no effect on radiation-induced c-Jun phosphorylation by individual depletion of ERK kinases. (E) BV2 cells were infected with combined lentiviruses (sh-ERK1-974/sh-ERK2-321 and sh-ERK1-974/sh-ERK2-772) and irradiated (10 Gy). Both shRNA combinations reduced radiation-stimulated phosphorylation of ERK1 and ERK2 to low levels, and decreased phosphorylated c-Jun after radiation. Bar graph depicts quantification (means ± SD) of relative c-Jun phosphorylation level, **<i>p</i><0.01(#3 vs. #2; #4 vs. #2). (F) JNK levels in ERK1/2 knockdown BV2 cells.</p