Long non-coding RNA SNHG4 aggravates cigarette smoke-induced COPD by regulating miR-144-3p/EZH2 axis.

OBJECTIVE: The purpose of this study was to explore the expression level of SNHG4 in patients with COPD and its diagnostic value in COPD, to probe the biological function of SNHG4 in COPD at the cellular level, and to reveal the interaction between SNHG4 and miR-144-3p/EZH2 axis. METHODS: The serum levels of SNHG4, miR-144-3p and EZH2 in healthy people and patients with COPD were detected by RT-qPCR. The diagnostic value of SNHG4 in COPD was evaluated by ROC curve. Pearson method was chosen to estimate the correlation between SNHG4 and clinical indicators in patients with COPD. Cigarette smoke extract (CSE) was obtained, and Beas-2B cells were exposed with 2% CSE to establish an inflammatory cell model of COPD in vitro. MTT assay was used to detect cell viability, flow cytometry was used to evaluate cell apoptosis, and ELISA was performed to detect inflammatory cytokines. Dual-luciferase reporting assay was carried out to verify the targeting of lncRNA-miRNA or miRNA-mRNA. RESULTS: (1) The expression of SNHG4 is decreased in patients with COPD, and the expression level in acute exacerbation COPD was lower than that in stable COPD. SNHG4 demonstrated high diagnostic accuracy in distinguishing between stable and acute exacerbation COPD. (2) The expression of SNHG4 was decreased in CSE-induced Beas-2B cells, and overexpression of SNHG4 was beneficial to alleviate CSE-induced apoptosis and inflammation. (3) The expression of miR-144-3p is up-regulated in patients with COPD and CSE-induced Beas-2B cells. MiR-144-3p has a targeting relationship with SNHG4, which is negatively regulated by SNHG4. Overexpression of miR-144-3p could counteract the beneficial effects of increased SNHG4 on CSE-induced cells. (4) The expression of EZH2 is reduced in patients with COPD and CSE-induced Beas-2B cells. Bioinformatics analysis and luciferase reporter gene confirmed that EZH2 is the downstream target gene of miR-144-3p and is negatively regulated by miR-144-3p. CONCLUSION: The expression of SNHG4 decreased in patients with COPD, and it may promote the progression of COPD by inhibiting the viability, promoting apoptosis and inflammatory response of bronchial epithelial cells via regulating the miR-144-3p/EZH2 axis.

Elastic 3D-Printed Hybrid Polymeric Scaffold Improves Cardiac Remodeling after Myocardial Infarction.

Myocardial remodeling, including ventricular dilation and wall thinning, is an important pathological process caused by myocardial infarction (MI). To intervene in this pathological process, a new type of cardiac scaffold composed of a thermoset (poly-[glycerol sebacate], PGS) and a thermoplastic (poly-[ε-caprolactone], PCL) is directly printed by employing fused deposition modeling 3D-printing technology. The PGS-PCL scaffold possesses stacked construction with regular crisscrossed filaments and interconnected micropores and exhibits superior mechanical properties. In vitro studies demonstrate favorable biodegradability and biocompatibility of the PGS-PCL scaffold. When implanted onto the infarcted myocardium, this scaffold improves and preserves heart function. Furthermore, the scaffold improves several vital aspects of myocardial remodeling. On the morphological level, the scaffold reduces ventricular wall thinning and attenuated infarct size, and on the cellular level, it enhances vascular density and increases M2 macrophage infiltration, which might further contribute to the mitigated myocardial apoptosis rate. Moreover, the flexible PGS-PCL scaffold can be tailored to any desired shape, showing promise for annular-shaped restraint device application and meeting the demands for minimal invasive operation. Overall, this study demonstrates the therapeutic effects and versatile applications of a novel 3D-printed, biodegradable and biocompatible cardiac scaffold, which represents a promising strategy for improving myocardial remodeling after MI.