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Fibroblast growth factor (FGF)-21 is a novel regulator of insulin-independent glucose transport in 3T3-L1 adipocytes and has glucose and triglyceride lowering effects in rodent models of diabetes. In this study, we found that FGF-21 can significantly attenuate ischemia-reperfusion (I/R) induced damage in H9c2 cells (rat heart). However, it is unclear which signal transduction pathway is involved in the cardioprotective effect of FGF-21. Thus, this study was designed to investigate the potential mechanism induced by FGF-21. The results showed that FGF-21 treatment prevented the oxidative stress and apoptosis associated with I/R damage by reducing the levels of superoxide anions, inhibiting glycogen synthase kinase (GSK) 3β by activating Akt phosphorylation, and recovering the levels of ATP synthase pyruvate kinase isozymes M1 and protein kinase C, thereby improving energy supply. In summary, we conclude that FGF-21 protects H9c2 cells against I/R injury mainly through the Akt-GSK-3β-caspase-3 dependent pathway, preventing oxidative stress, and recovery of the energy supply. Key words: FGF-21, myocardial ischemia-reperfusion, H9c2, proteomics, Akt, ROS, apoptosis, signaling pathway. Le facteur de croissance des fibroblastes (FGF)-21 est nouveau regulateur du transport de glucose independant de l'insuline dans les adipocytes 3T3-L1 qui diminue le glucose et les triglycerides dans des modeles de diabete chez le rongeur. Dans cette etude, nous avons trouve que le FGF-21 pouvait attenuer significativement le dommage induit par l'ischemiereperfusion (I/R) chez les cellules H9c2. Cependant, la voie de transduction impliquee dans l'effet cardioprotecteur du FGF-21 n'est pas clairement definie. Ainsi, cette etude a ete concue pour examiner le mecanisme d'action potentiel du FGF-21. Les resultats ont montre que le traitement au FGF-21 prevenait le stress oxydant et l'apoptose associes au dommage d'I/R en reduisant les anions superoxydes, inhibait la glycogene synthase kinase (GSK)-3β en activant la phosphorylation d'Akt, et restaurait l'ATP synthase, les isozymes M1 de la pyruvate kinase et la proteine kinase C afin d'ameliorer l'apport en energie. En resume, nous concluons que le FGF-21 protege les cellules H9c2 du dommage d'I/R principalement par l'intermediaire de la voie dependante d'Akt-GSK-3β-caspase-3, du stress anti-oxydant et de la restauration de l'apport energetique. [Traduit par la Redaction] Mots-cles: FGF-21, ischemie-reperfusion myocardique, H92c, proteomique, Akt, ERO, apoptose, voie de signalisation., Introduction It has been reported that ischemia-reperfusion (I/R) injury is commonly associated with oxidative stress, and that reactive oxygen species (ROS) are the major mediators contributing to acute myocardial injury [...]

A Schiff base compound derived from naphthalene has been synthesized and characterized as an Al3+-selective fluorescent probe. The chemosensor ( L) exhibits high selectively for Al3+ in aqueous solution, even in the presence of biologically relevant cations such as Na+, K+, Ca2+, Mg2+, Pb2+ and several transition metal ions. There was no observed interference from anions like Br−, Cl−, HSO3−, SO32−, S2O32−, NO2−, CO32− and AC−. The lowest detection limit for the chemosensor L was found to be 1.89 × 10−8 M with a linear response towards Al3+ over a concentration range of 5 × 10−6 to 4 × 10−5 M. Furthermore, the proposed chemosensor has been used for imaging of Al3+ in two different types of cells with satisfying results, which further demonstrates its value for practical application in biological systems. [ABSTRACT FROM AUTHOR]

One of the major symptoms of diabetes mellitus (DM) is delayed wound healing, which affects large populations of patients worldwide. However, the underlying mechanism behind this illness remains elusive. Skin wound healing requires a series of coordinated processes, including fibroblast cell proliferation and migration. Here, we simulate DM by application of high glucose (HG) in human foreskin primary fibroblast cells to analyze the molecular mechanism of DM effects on wound healing. The results indicate that HG, at a concentration of 30 mM, delay cell migration, but not cell proliferation. bFGF is known to promote cell migration that partially rescues HG effects on cell migration. Molecular and cell biology studies demonstrated that HG enhanced ROS production and repressed JNK phosphorylation, but did not affect Rac1 activity. JNK and Rac1 activation were known to be important for bFGF regulated cell migration. To further confirm DM effects on skin repair, a type 1 diabetic rat model was established, and we observed the efficacy of bFGF on both normal and diabetic rat skin repair. Furthermore, proteomic studies identified an increase of Annexin A2 protein nitration in HG-stressed fibroblasts and the nitration was protected by activation of bFGF signaling. Treatment with FGFR1 and JNK inhibitors delayed cell migration and increased Annexin A2 nitration levels, indicating that Annexin A2 nitration is modulated by bFGF signaling via activation of JNK. Together with these results, our data suggests that the HG-mediated delay of cell migration is linked to the inhibition of bFGF signaling, specifically through JNK suppression. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive and simple technique for the negative detection of lipopolysaccharides (LPSs) following polyacrylamide gel electrophoresis (PAGE) using eosin B (EB) was developed. After electrophoresis, gels were fixed, stained, and developed within 30min to achieve transparent and colorless LPS bands under opaque gel matrix background. As low as 20 to 40ng of total LPSs could be detected, which is 4-fold more sensitive than those of the widely used silver stain developed by Fomsgaard and coworkers and imidazole–zinc (IZ) negative stain. For its sensitivity and brevity, this stain may be a practical method for LPS determination in the routine laboratory. [Copyright &y& Elsevier]

Abstract: We describe a visible dye-based staining method for DNA in polyacrylamide gels using ethyl violet (EV). The novel method is a background-free, sensitive, economical, and simple procedure involving only staining and washing steps that can be completed within 30 min. As little as 0.8–1.6ng of φX174 DNA/HaeIII can be detected by EV, which is about eightfold more sensitive than Nile blue (NB) stain and twofold less sensitive than ethidium bromide (EB) stain. [Copyright &y& Elsevier]

In order to achieve an easy, rapid and sensitive protocol to detect proteins in polyacrylamide gel, an advanced negative detection method comparable to silver stain is described. When a gel was incubated with Phloxine B and followed by the development in acidic solution, the zones where forming protein-dye complex were selectively transparent, unlike opaque gel background. Within 50 min after electrophoresis, down to 0.1–0.4 ng of gel-separated proteins (similar with silver stain) could be observed, without labor-intensive and time-consuming procedure. Comparing with the most common negative stain method, Imidazole-zinc stain, Phloxine B stain has been shown higher sensitivity and distinct contrast between the transparent protein bands/spots and opaque background than those; furthermore, it is no longer necessary to concern about retention time of observation. This technique may provide a sensitive and practical choice for proteomics researches. [ABSTRACT FROM AUTHOR]

Abstract: A fluorescence-based stain with 3,5,7,2′,4′-pentahydroxyflavone (morin hydrate, MH) was designed to stain phosphoproteins in one-dimensional sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS–PAGE). Al3+ was applied as a “fixed bridge,” providing an efficient energy transfer channel between phosphoprotein and MH, to produce a strong fluorescent complex for the determination of phosphoprotein. As little as 62.5ng of α-casein (7 or 8 phosphates) and β-casein (5 phosphates), 125ng of ovalbumin (2 phosphates), and κ-casein (1 phosphate) could be visualized with a wide linear dynamic range. In comparison with conventional methods, MH stain is a time-saving method that takes just 90min. It also has good compatibility with routine protein stainings such as Coomassie Brilliant Blue R (CBBR) and SYPRO Ruby for total protein analysis. [Copyright &y& Elsevier]

Fibroblast migration is a central process in skin wound healing, which requires the coordination of several types of growth factors. bFGF, a well-known fibroblast growth factor (FGF), is able to accelerate fibroblast migration; however, the underlying mechanism of bFGF regulation fibroblast migration remains unclear. Through the RNA-seq analysis, we had identified that the hedgehog (Hh) canonical pathway genes including Smoothened (Smo) and Gli1, were regulated by bFGF. Further analysis revealed that activation of the Hh pathway via up-regulation of Smo promoted fibroblast migration, invasion, and skin wound healing, but which significantly reduced by GANT61, a selective antagonist of Gli1/Gli2. Western blot analyses and siRNA transfection assays demonstrated that Smo acted upstream of phosphoinositide 3-kinase (PI3K)-c-Jun N-terminal kinase (JNK)-β-catenin to promote cell migration. Moreover, RNA-seq and qRT-PCR analyses revealed that Hh pathway genes including Smo and Gli1 were under control of β-catenin, suggesting that β-catenin turn feedback activates Hh signaling. Taken together, our analyses identified a new bFGF-regulating mechanism by which Hh signaling regulates human fibroblast migration, and the data presented here opens a new avenue for the wound healing therapy. [ABSTRACT FROM AUTHOR]