Long noncoding RNA HOTTIP promotes endothelial cell proliferation and migration via activation of the Wnt/ß-catenin pathway.

Atherosclerosis is the major cause of stroke and heart disease. However, the course and pathogenesis of atherosclerosis remains unknown. The proliferation and migration of endothelial cell play important roles in the inition and pathological progression of atherosclerosis. In this study, we demonstrated that long noncoding RNA (lncRNA) HOXA transcript at the distal tip (HOTTIP) expression level was higher in coronary artery disease (CAD) tissues than in normal arterial tissues. The expression level of HOTTIP was upregulated in the proliferating endothelial cells induced by TNF-α or PDGF-BB. Ectopic expression of HOTTIP promoted endothelial cell proliferation and also increased the expression of proliferating makers cyclin D1 and PCNA. Moreover, elevated expression of HOTTIP promoted endothelial cell migration. Downregulation expression of HOTTIP suppressed endothelial cell proliferation and migration. Furthermore, we determined that overexpression of HOTTIP induced ß-catenin expression and enhanced the downstream protein c-Myc expression in the endothelial cell. Ectopic expression of HOTTIP increased endothelial cell proliferation and migration via activation of the Wnt/ß-catenin pathway. These results suggested that HOTTIP might manipulate the endothelial cell proliferation and migration via activation of the Wnt/ß-catenin pathway.

Imperatorin protects H9c2 cardiomyoblasts cells from hypoxia/reoxygenation-induced injury through activation of ERK signaling pathway.

BACKGROUND: Imperatorin is a compound found in plants and has been widely used in Chinese medicine for many years. It has many pharmacological effects, including the recently reported anti-apoptotic function, however, the mechanism largely remains unclear. This study is aimed to elucidate the mechanism of Imperatorin's anti-apoptotic function. METHODS: A model of hypoxia and reoxygenation (H/R) treated h9c2 cardiomyoblasts was successfully constructed. The cells were treated with H/R condition, and followed by adding Imperatorin alone, Imperatorin with ERK inhibitor and/or ERK inhibitor alone, to examine the cell viability by Cell Counting Kit-8 assay, cell apoptosis rate by flow cytometry, and ERK expression by Western-blot under different conditions. RESULTS: The results showed that imperatorin exerted protective effect on h9c2 cells from H/R injure. It was also found that it not only increased cell viability but also reduced the apoptotic rate for H/R treated h9c2 cells. The experiments also demonstrated that imperatorin could upregulate the expression levels of both ERK1 and ERK2, which is a key step in ERK signaling pathway activation. CONCLUSIONS: These findings provided evidence that imperatorin could increase the cell viability and lower apoptotic rate in H/R treated h9c2 cells, and could also enhance the expression of ERK1/ERK2, demonstrating imperatorin's protective effect on H/R injured h9c2 cells through ERK signaling pathway.

Relationship of SELE A561C and G98T Variants With the Susceptibility to CAD.

Published genetic association studies have produced controversial results regarding the association of SELE gene polymorphisms (A516C and G98T) and CAD susceptibility. We therefore chose to perform a meta-analysis to determine the association.Twenty-seven eligible articles were identified through electronic databases, providing 5170 CAD cases and 4996 controls. Fixed-effects or random-effects summary ORs were calculated to estimate the risk of CAD in relation to A516C and G98T. Forest plots and funnel plots were constructed by Stata software 12.0.A strong association was observed between A516C and susceptibility of CAD among 4757 cases and 4272 controls. The summary OR was greatest in individuals carrying the CC genotype (OR = 1.91, 95% CI, 1.12-3.25). A significantly increased risk was indicated in both Caucasians and Asians. The analyses by disease type showed a significant increase in the risk of AP and MI. We also noted a strong association in population-based studies. In the analyses of G98T, data were available for 1422 cases and 1625 controls. We saw a markedly increased risk of CAD associated with G98T. The highest risk was indicated in individuals with the TT genotype (OR = 2.82, 95% CI, 1.15-6.89). A similar trend was seen in Asians and population-based studies.These findings provide consistent evidence that A516C and G98T polymorphisms of the SELE gene may be associated with increased susceptibility of CAD.