Interleukin-6 as possible early marker of stress response after femoral fracture

Toll-like receptor 4 (TLR4) activation is a key contributor to the carcinogenesis of colon cancer. Overexpression of galectin-1 (Gal-1) also correlates with increased invasive activity of colorectal cancer. Lactate production is a critical predictive factor of risk of metastasis, but the functional relationship between intracellular lactate and Gal-1 expression in TLR4-activated colon cancer remains unknown. In this study, we investigated the underlying mechanism and role of Gal-1 in metastasis and invasion of colorectal cancer (CRC) cells after TLR4 stimulation. Exposure to the TLR4 ligand lipopolysaccharide (LPS) increased expression of Gal-1, induced EMT-related cytokines, triggered the activation of glycolysis-related enzymes, and promoted lactate production. Gene silencing of TLR4 and Gal-1 in CRC cells inhibited lactate-mediated epithelial-mesenchymal transition (EMT) after TLR4 stimulation. Gal-1-mediated activation of a disintegrin and metalloproteinase 10 (ADAM10) and ADAM 17 increased the invasion activity and expression of mesenchymal characteristics in LPS-activated CRC cells. Conversely, inhibition of ADAM10 or ADAM17 effectively blocked the generation of lactate and the migration capacity of LPS-treated CRC cells. Thus, the TLR4/Gal-1 signaling pathway regulates lactate-mediated EMT processes through the activation of ADAM10 and ADAM17 in CRC cells.     

Cytotoxicity of commonly used nitroxide radical spin probes

Since nitroxide radical spin probes are used frequently to test biophysical properties of cells, their use should be restricted to conditions that do not perturb normal cell growth and viability. Eight commonly used nitroxide radical spin probes have been tested for their effects on the survival of CHO cells. These include water-soluble spin probes Tempol, Tempamine, CTPO, CTPC and 4-maleimido-Tempo, and lipid soluble spin probes 5-Doxyl-, 12-Doxyl-, and 16-Doxylstearates. With the exception of 4-maleimido-Tempo, none of the water soluble spin labels inhibited cell survival at concentrations as high as 1 mM. At concentrations of 75 microM and higher, 4-maleimido-Tempo inhibited cell survival in a dose dependent manner. At concentrations commonly used for spin labeling of cells (30-50 microM) none of the lipid soluble spin probes tested was cytotoxic. At 100 microM only 5-Doxylstearate inhibited cell survival, whereas 12-Doxylstearate and 16-Doxylstearate had no effect.     

Polar localization of plasma membrane Ca2+/Mg2+ ATPase correlates with the pattern of steady ionic currents in eggs ofLymnaea stagnalis andBithynia tentaculata (Mollusca)

Summary During extrusion of the first polar body in eggs ofLymnaea stagnalis andBithynia tentaculata a localized Ca²⁺ /Mg²⁺ ATPase activity was detected, using Ando's enzyme-cytochemical method for electron microscopy [Ando et al. (1981) Acta Histochem Cytochem 14:705–726]. The enzyme activity was distributed in a polar fashion, along the cytoplasmic face of the plasma membrane. In the eggs ofLymnaea it was found only in the vegetal hemisphere, whereas inBithynia eggs it was localized both in the vegetal hemisphere and at the animal pole. This pattern of enzyme activity corresponds to the polar pattern of transcellular ionic currents measured with the vibrating probe, which we showed to be partially carried or regulated by calcium [Zivkovic and Dohmen (1989) Biol Bull (Woods Hole) 176 (Suppl):103–109]. The characteristics of the ATPase were studied using a variety of approaches such as ion and substrate depletions and substitutions, addition of specific inhibitors of ATPase activity, treatment with EDTA/EGTA and electron energy-loss spectrometry. The results indicate that, inLymnaea, there are at least two enzymatic entities. The first one is a Ca²⁺ /Mg²⁺ ATPase localized along the membrane and in the cortex of the vegetal hemisphere. The second one is a Ca²⁺-stimulated ATPase (calcium pump of the plasma membrane) localized in a small region of the membrane at the vegetal pole. We speculate that in the eggs ofLymnaea andBithynia a functional relationship exists between the plasma-membrane-associated ATPase activity and the transcellular ionic currents measured in the same region.     

Localized activity of Ca2+-stimulated ATPase and transcellular ionic currents during mesoderm induction in embryos ofLymnaea stagnalis (Mollusca)

Summary InLymnaea stagnalis, mesoderm induction occurs at the 24-cell stage, when the apical tip of the macromere 3D establishes a close contact with a number of micromeres. Via its tip, the macromere 3D is supposed to receive an inductive signal from the micromeres, resulting in the determination of the mesodermal stem cell 4d at the next division. In view of the possibility that transcellular ionic currents might somehow be involved, either in the processes that bring about this particular configuration of blastomeres or in the induction process itself, we mapped the electric field around the embryo during the 24-cell stage, using a vibrating probe. We detected a reversal of the current direction as compared to the uncleaved egg, whilst the polarity of the field along the animal-vegetal axis was maintained. We also mapped the localization of Ca²⁺-stimulated AT-Pase, an enzyme that drives the Ca²⁺-efflux from the cell. We found that this enzyme is localized exclusively along the cytoplasmic face of the apical plasma membrane of macromere 3D, and that its presence is restricted to the period from 110 to 135 min after the fifth cleavage, when there is close contact between macormere 3D and the micromeres. Since the localization of the Ca²⁺-stimulated ATPase coincides both in time and space with the induction of the mesoderm-mother cell, we suggest that localized calcium fluxes may play a role in this induction process.     

Follicular fluid vascular endothelial growth factor is associated with type of infertility and interferon alpha correlates with endometrial thickness in natural cycle in vitro fertilization

The aim of this study was to analyse the presence of vascular endothelial growth factor (VEGF) and interferon alpha (IFN-α) in the follicular fluid (FF) and their possible influence, as pro-angiogenic or anti-angiogenic factors, on in vitro fertilization outcome. The concentrations of VEGF and IFN-α were correlated with oocyte and embryo quality, concentrations of hormones in the serum, perifollicular blood flow and endometrial thickness. VEGF was detected in all FF samples (median 706.6?pg/ml, range 182.9–6638?pg/ml). IFN-α was detected in 60% of the samples (median 6.5?pg/ml, range 0–79.4?pg/ml), while in 40% of the samples its levels were below the test detection limit. VEGF and IFN-α concentrations did not correlate with the cause of infertility, concentrations of FSH, LH, E2 and prolactin, oocyte or embryo quality. Significantly higher concentrations of VEGF have been found in women with primary compared with secondary infertility (p?=?0.011, Mann Whitney test). The concentrations of VEGF and IFN-α did not correlate with the resistance index (RI) on days of hCG administration, follicular aspiration and embryo transfer. However, the concentrations of IFN-α correlated with endometrial thickness on the day of embryo transfer (Spearman correlation coefficient ρ?=?0.4107; P?<?0.05) but not on days of hCG administration and follicular aspiration. The mechanism of VEGF association with the previous ability of having a child needs to be clarified in future studies. The results of this study indicate a possible role of IFN-α in pathways of endometrial remodelling.