WSB1, as an E3 ligase, restrains myocardial ischemia-reperfusion injury by activating ß-catenin signaling via promoting GSK3ß ubiquitination.

BACKGROUND: Reperfusion is the most effective strategy for myocardial infarct, but induces additional injury. WD repeat and SOCS box containing protein 1 (WSB1) plays a protective role in ischemic cells. This study aims to investigate the effects of WSB1 on myocardial ischemia-reperfusion (IR) injury. METHODS: The myocardial IR was induced by left anterior descending (LAD) ligation for 45 min and subsequent reperfusion. The overexpression of WSB1 was mediated by tail vein injection of AAV9 loaded with WSB1 encoding sequence two weeks before IR surgery. H9c2 myocardial cells underwent oxygen-sugar deprivation/reperfusion (OGD/R) to mimic IR, and transfected with WSB1 overexpression or silencing plasmid to alter the expression of WSB1. RESULTS: WSB1 was found highly expressed in penumbra of myocardial IR rats, and the WSB1 overexpression relieved IR-induced cardio dysfunction, myocardial infarct and pathological damage, and cardiomyocyte death in penumbra. The ectopic expression of WSB1 in H9c2 myocardial cells mitigated OGD/R-caused apoptosis, and silencing of WSB1 exacerbated the apoptosis. In addition, WSB1 activated ß-catenin signaling, which was deactivated under the ischemic condition. The co-immunoprecipitation results revealed that WSB1 mediated ubiquitination and degradation of glycogen synthase kinase 3 beta (GSK3ß) as an E3 ligase in myocardial cells. The effects of WSB1 on myocardial cells under ischemic conditions were abolished by an inhibitor of ß-catenin signaling. CONCLUSION: WSB1 activated ß-catenin pathway by promoting the ubiquitination of GSK3ß, and restrained IR-induced myocardial injury. These findings might provide novel insights for clinical treatment of myocardial ischemic patients.

Ultrasound and microbubble-mediated delivery of miR-424-5p has a therapeutic effect in preeclampsia.

OBJECTIVE: To determine the influence of ultrasound/microbubble-mediated miR-424-5p delivery on trophoblast cells and the underlying mechanism. METHODS: Blood pressure and 24-h proteinuria of patients with preeclampsia (PE) were measured as well as the levels of miR-424-5p and amine oxidase copper containing 1 (AOC1) in placental tissues. HTR-8/Svneo and TEV-1 cells were subjected to cell transfection or ultrasonic microbubble transfection for determination of the expression of miR-424-5p, AOC1, ß-catenin and c-Myc as well as cell proliferation, apoptosis, migration and invasiveness. The concentrations of placental growth factor (PLGF), human chorionic gonadotropin (ß-hCG) and tumor necrosis factor-α (TNF-α) were measured in HTR-8/Svneo and TEV-1 cells. RNA immunoprecipitation (RIP) and dual luciferase reporter assay detected the binding of miR-424-5p to AOC1. A PE mouse model was induced by subcutaneous injection of L-NAME, where the influence of ultrasound/microbubble-mediated miR-424-5p delivery was evaluated. RESULTS: miR-424-5p was downregulated while AOC1 was upregulated in the placental tissues from PE patients. Overexpression of miR-424-5p activated Wnt/ß-catenin signaling pathway and promoted the proliferation of HTR-8/Svneo and TEV-1 cells as well as enhanced the migratory and invasive behaviors. AOC1 overexpression partly eliminated the effects of miR-424-5p on HTR-8/Svneo and TEV-1 cells. Ultrasound and microbubble mediated gene delivery enhanced the transfection efficiency of miR-424-5p and further promoted the effects of miR-424-5p in trophoblast cells. Ultrasound/microbubble-mediated miR-424-5p delivery alleviated experimental PE in mice. CONCLUSION: Ultrasound and microbubble-mediated miR-424-5p delivery targets AOC1 and activates Wnt/ß-catenin signaling pathway, thus promoting the aggressive phenotype of trophoblast cells, which indicating that miR-424-5p/AOC1 axis might be involved with PE pathogenesis.

Calycosin-7-O-ß-D-glucoside attenuates myocardial ischemia-reperfusion injury by activating JAK2/STAT3 signaling pathway via the regulation of IL-10 secretion in mice.

Calycosin-7-O-ß-D-glucoside (CG) is the component of Astragali Radix, and the aim of the present study is to investigate whether CG protects myocardium from I/R-induced damage by the regulation of IL-10/JAK2/STAT3 signaling pathway. H9C2 cells were subjected to I/R treatment and pretreated with 1 µm CG in vitro. In addition, a mouse model of myocardial I/R injury was induced by left anterior descending (LAD) coronary artery ligation and administrated with 30 mg/kg CG by intravenous injection before I/R surgery. In vitro and in vivo results showed that CG up-regulated IL-10 level, activated the JAK2/STAT3 pathway, and protected myocardial cells from I/R-induced apoptosis. The hemodynamic measurement, TTC staining, TUNEL staining, and western blot results in vivo showed that the protective effects of CG on myocardial function and cell apoptosis were all reversed by the IL-10R α neutralizing antibody. CG-induced phosphorylation activation of JAK2/STAT3 signaling pathway was also suppressed by the blocking of IL-10. In summary, these findings suggest that CG might alleviate myocardial I/R injury by activating the JAK2/STAT3 signaling pathway via up-regulation of IL-10 secretion, which provides us insights into the mechanism underlying the protective effect of CG on myocardial I/R injury.