Glycogen synthase kinase 3 inhibition protects the heart from acute ischemia-reperfusion injury via inhibition of inflammation and apoptosis.

Glycogen synthase kinase (GSK)-3beta inhibitors play an anti-inflammatory role in several inflammatory diseases. Recent studies have demonstrated that GSK-3beta inhibitors protect against myocardial ischemia-reperfusion injury. However, the precise mechanisms remain unclear. We aimed to investigate the roles of inflammation and apoptosis induced by ischemia-reperfusion in the cardioprotection by GSK-3beta inhibitor 4-benzyl-2-methyl-1, 2, 4-thiadiazolidine-3, 5-dione (TDZD-8). Anaesthetized Sprague-Dawley rats underwent an open-chest procedure involving 30 min of myocardial ischemia and 6 h of reperfusion with or without TDZD-8 given at reperfusion. TDZD-8 reduced myocardial infarct size by nearly 43% (P < 0.05 vs. myocardial ischemia-reperfusion) and attenuated myeloperoxidase activity (21.80 +/- 1.07 U/100 mg tissue. vs. myocardial ischemia-reperfusion group, P < 0.05). Administration of TDZD-8 significantly suppressed nuclear factor kappa B (NF-kappaB) and p38 MAPK activation (P < 0.05 vs. myocardial ischemia-reperfusion) and the concentrations of the myocardial-derived cytokines tumor necrosis factor-alpha (TNF-alpha, 107.40 +/- 7.34 pg/mg protein vs. myocardial ischemia-reperfusion group, P < 0.05) and interleukin-6 (IL-6, 29.28 +/- 6.3 pg/mg protein vs. myocardial ischemia-reperfusion group, P < 0.05). Treatment with TDZD-8 also inhibited myocardial cell apoptosis compared with the myocardial ischemia-reperfusion group (12 +/- 1% vs. 22 +/- 2%, P < 0.05). Therefore, blocking this protein kinase activity may be a novel approach to the treatment of this condition, which is characterized by inflammation and apoptosis.

Low strength static magnetic field inhibits the proliferation, migration, and adhesion of human vascular smooth muscle cells in a restenosis model through mediating integrins ß1-FAK, Ca2+ signaling pathway.

The proliferation, migration, and adhesion of vascular smooth muscle cells (VSMCs) and their interactions with extracellular matrix are key features of atherosclerosis and restenosis. Recently, there has been evidence that magnetic fields exert multiple effects on the biological performance of cells and may aid in the treatment of vascular disease. However, the effect of a static magnetic field (SMF) on human VSMCs still remains unknown. In this study, we aimed to determine the effects of low strength SMF on human VSMCs in an in vitro restenosis model. A SMF was established using neodymium-yttrium-iron permanent magnet. Human umbilical artery smooth muscle cells (hUASMCs) were isolated and seeded to a fibronectin-coated plate to form an in vitro restenosis model and then exposed to a vertically oriented field of 5 militesla (mT). MTT, transwell, and adhesion assays were used to demonstrate that the proliferation, migration, and adhesion potential of hUASMCs were significantly decreased after exposure to 5 mT SMF for 48 h compared with a non-treated group. Meanwhile, confocal microscopy analysis was used to demonstrate that integrin ß(1) clustering was inhibited by exposure to 5 mT SMF. Furthermore, the phosphorylation of focal adhesion kinase (FAK) was markedly inhibited, and the upregulated cytosolic free calcium had been reversed (p < 0.05). However, the biological effects of low strength SMF on hUASMCs could be blocked by the administration of GRGDSP-the blockade of integrins. In conclusion, a low strength SMF can influence the proliferation, migration, and adhesion of VSMCs by inhibiting the clustering of integrin ß1, decreasing cytosolic free calcium concentration, and inactivating FAK. With further validation, SMFs may aid in attenuating abnormal VSMCs biological performance and has potential to block atherogenesis and prevent restenosis.