Dissecting Microscopes

purpose. The stromal-derived factor (SDF)-1 and the CXC receptor (CXCR)-4 jointly regulate the trafficking of various cell types and play a pivotal role in cell migration, proliferation, and survival. The purpose of this study was to assess whether curcumin inhibits human retinal endothelial cell (HREC) migration by interfering with SDF-1/CXCR4 signaling.

methods. Primary HREC culture was established and maintained in endothelial growth medium. The viability and proliferation of HRECs were assessed by MTT and thymidine uptake assays, respectively. The effect of SDF-1–induced HREC migration (chemotaxis) in the presence and absence of curcumin was determined using the Boyden chamber migration assay. Intracellular Ca²⁺ concentration was measured by fluorometric analysis. Immunofluorescence and Western blot analyses were performed to quantify CXCR4, phosphorylated AKT, and PI3-kinase expression levels.

results. HREC migration increased in a dose-dependent manner (1, 10, 50, and 100 ng/mL; P < 0.001) in SDF-1–treated cells. In contrast, AMD3100, an inhibitor of CXCR4 effectively inhibited HREC migration dose dependently. HREC migration was decreased when the cells were exposed to EGTA, a chelator of Ca²⁺. Curcumin also blocked Ca²⁺ influx, an important signal for HREC migration. In addition, curcumin significantly (P < 0.001) decreased SDF-1–induced HRECs migration and downregulated SDF-1–induced expression of CXCR4, phospho-AKT, phospho-phosphatidylinositol-3-kinase (PI3-K), and eNOS.

conclusions. This study indicates that curcumin has an inhibitory effect on SDF-1–induced HREC migration. The plausible mechanism of action could be upstream blockage of Ca²⁺ influx and the downstream reduction of PI3-K/AKT signals.

Two series of glasses of general formula (2-p) SiO₂·1.1Na ₂O·CaO·pP₂O₅·xZnO (p=0.10, 0.20; x=0.0, 0.16, 0.35, and 0.78) have been analyzed for physico-chemical surface features before and after contact with simulated body fluid, morphological characteristics, and osteoblast-like cells behavior when cultured on them. The resulted good cell adhesion and growth, along with nonsignificant changes of the focal contacts, allow the authors to indicate HZ5 and HP5Z5 glasses as the ones having optimal ratio of Zn/P to maintain acceptable cell behavior, comparable to the bioactive glass (Bioglass^®) used as a control; results are also rationalized by means of three-dimensional models derived by molecular dynamic simulations, with decomposition and conversion rates optimized with respect to the parent Hench's Bioglass^®.