Retraction Notice to: MicroRNA-494 Inhibits the LRG1 Expression to Induce Proliferation and Migration of VECs in Rats following Myocardial Infarction.

[This retracts the article DOI: 10.1016/j.omtn.2019.08.007.].

Myocardial ischemia reperfusion injury is alleviated by curcumin-peptide hydrogel via upregulating autophagy and protecting mitochondrial function.

BACKGROUND: Ischemia-reperfusion injury (IRI) is an important factor limiting the success of cardiac reperfusion therapy. Curcumin has a significant cardioprotective effect against IRI, can inhibit ventricular remodeling induced by pressure load or MI, and improve cardiac function. However, the poor water solubility and low bioavailability of curcumin restrict its clinical application. METHODS: In this study, we prepared and evaluated a curcumin-hydrogel (cur-hydrogel) to reduce cardiomyocyte apoptosis and reactive oxygen species formation induced by hypoxia-reoxygenation injury, promote autophagy, and reduce mitochondrial damage by maintaining the phosphorylation of Cx43. RESULTS: Meanwhile, cur-hydrogel can restore cardiac function, inhibit myocardial collagen deposition and apoptosis, and activate JAK2/STAT3 pathway to alleviate myocardial ischemia-reperfusion injury in rats. CONCLUSIONS: The purpose of this study is to elucidate the protective effects of cur-hydrogel on myocardial ischemia-reperfusion injury by regulating apoptosis, autophagy, and mitochondrial injury in vitro and in vivo, which lays a new theoretical and experimental foundation for the prevention and reduction of IRI.

MicroRNA-494 Inhibits the LRG1 Expression to Induce Proliferation and Migration of VECs in Rats following Myocardial Infarction.

Myocardial infarction (MI) is a life-threatening cardiac event that results in extreme damage to the heart muscle. The Wnt signaling pathway has been implicated in the development of heart diseases. Hence, the current study aimed to investigate the role of microRNA (miRNA) in association with the Wnt signaling pathway to identify potential candidates for MI therapy. Differentially expressed miRNAs associated with MI occurrence were screened, and miR-494 was selected for subsequent experiments. Sprague-Dawley rats were included to establish a MI model via intraperitoneal injection of 0.1 mg/kg atropine sulfate and 40 mg/kg pentobarbital sodium. Then, the interaction between miR-494 and LRG1 was identified. The effect of miR-494 on expression of the Wnt signaling pathway-related genes, proliferation, migration, and invasion ability of fibroblasts and vascular endothelial cells (VECs) was subsequently evaluated through a series of gain- and loss-of-function experiments. The results revealed that miR-494 was poorly expressed and LRG1 was highly expressed in MI rats. miR-494 targets and downregulates LRG1, which resulted in the inactivation of the Wnt signaling pathway and promoted proliferation, migration, and invasion ability of fibroblasts and VECs. In conclusion, this study provided evidence suggesting that overexpressed miR-494 could potentially promote the proliferation, migration, and invasion of fibroblasts and VECs in MI through the inactivation of the Wnt signaling pathway by binding to LRG1.

Inhibition of lncRNA TUG1 upregulates miR-142-3p to ameliorate myocardial injury during ischemia and reperfusion via targeting HMGB1- and Rac1-induced autophagy.

BACKGROUND: Long non-coding RNAs (lncRNAs) play a central role in regulating heart diseases. In the present study, we examined the effects of lncRNA taurine up-regulated gene 1 (TUG1) in ischemia/reperfusion (I/R)- or hydrogen peroxide-challenged cardiomyocytes, with specific focus on autophagy-induced cell apoptosis. METHODS: The expressions of miR-142-3p and TUG1 in H2O2-challenged cardiomyocytes and I/R-injured heart tissue were measured by RT-qPCR. Cell death was measured by trypan blue staining assay. Cell apoptosis was determined by Annexin V/PI staining and TUNEL assay. Autophagy was examined by quantifying cells or tissues containing LC3+ autophagic vacuoles by immunofluorescence, or by measuring the expressions of autophagy-related biomarkers by Western blot. The direct interaction between miR-142-3p and TUG1, high mobility group box 1 protein (HMGB1), or Ras-related C3 botulinum toxin substrate 1 (Rac1) was examined using luciferase reporter assay. The significance of miR-142-3p and TUG1 on cell apoptosis or autophagy was examined using both gain-of-function and loss-of-function approaches. The importance of HMGB1 or Rac1 was assessed using siRNA-mediated gene silencing. RESULTS: miR-142-3p was down-regulated, while TUG1 up-regulated in H2O2-challenged cardiomyocytes in vitro and I/R-injured heart tissues in vivo. Functionally, inhibition of TUG1 and overexpression of miR-142-3p inhibited cell apoptosis and autophagy in cardiomyocytes. The function of TUG1 were achieved by sponging miR-142-3p and releasing the suppression of the putative targets of miR-142-3p, HMGB1 and Rac1. Both HMGB1 and Rac1 essentially mediated cell apoptosis and autophagy induced by TUG1. CONCLUSIONS: TUG1, by targeting miR-142-3p and up-regulating HMGB1 and Rac1, plays a central role in stimulating autophagic cell apoptosis in ischemia/hypoxia-challenged cardiomyocytes. Down-regulating TUG1 or up-regulating miR-142-3p may ameliorate myocardial injury and protect against acute myocardial infarction.

Association between the level of CD4+ T lymphocyte microRNA-155 and coronary artery disease in patients with unstable angina pectoris.

OBJECTIVE: To study the association between the expression of microRNA-155 (miRNA-155) in peripheral blood CD4+ T lymphocytes and the level of serum interferon-γ (IFN-γ) concentration and the severity of coronary artery disease (CAD). METHODS: After coronary angiography, 252 patients with suspected unstable angina pectoris (UAP) were divided into the UAP group (128 patients with CAD confirmed by angiography) and the control group (124 patients without CAD confirmed by angiography). Fresh peripheral blood was extracted 16-24 h before coronary angiography, CD4+ T lymphocytes was tested using immunomagnetic beads, the expression of miRNA-155 was tested using quantitative PCR and the expression of IFN-γ was tested using enzyme-linked immunosorbent assay (ELISA). According to the results of angiography, Gensini score of coronary artery lesions was analyzed. Furthermore, we also analysis the association between the level of miRNA-155 in peripheral blood CD4+ T lymphocytes, the level of serum IFN-γ and Gensini score of coronary lesion. RESULTS: The levels of miRNA-155 (0.49 ± 0.08 vs. 0.23 ± 0.09) and IFN-γ (227.58 ± 26.01 vs. 141.23 ± 17.89) in the UAP group were significantly higher than that of the control group, the difference was statistically significant. The level of miRNA-155 and IFN-γ were positively correlated with Gensini score of CAD (r = 0.534, r = 0.713, respectively, all P < 0.05). The level of miRNA-155 was positively correlated with the level of IFN-γ (r = 0.686, P < 0.05). CONCLUSIONS: The level of miRNA-155 in peripheral blood CD4+ T lymphocytes and the level of IFN-γ are closely correlated with the severity of CAD.

Effect of Dipeptidyl Peptidase-4 Inhibitors on Heart Failure: A Network Meta-Analysis.

BACKGROUND: Previous meta-analyses evaluating the effectiveness of individual dipeptidyl peptidase-4 (DPP-4) inhibitors on the risk of heart failure (HF) were limited because of the small number of trials with direct comparisons between two treatments. METHODS: A Bayesian network meta-analysis was performed to investigate the relationship between DPP-4 inhibitors and the risk of HF in patients with type-2 diabetes mellitus. The primary outcome was the occurrence of HF or hospital admission for HF. RESULTS: Fifty randomized controlled trials were identified. Relative to placebo, no increased risk of HF events was seen for vildagliptin (risk ratio [RR] 0.71; 95% confidence interval [CI] 0.25-1.68), sitagliptin (RR 0.86; CI 0.43-1.57), or saxagliptin (RR 0.84; 95% CI 0.33-1.61), but alogliptin was associated with a higher risk of HF (RR 2.13; 95% CI 1.06-6.26). Vildagliptin and sitagliptin were associated with a significantly decreased risk of HF compared with alogliptin. Vildagliptin had the highest probability to be the safest option with regard to the risk of HF (49.18%), followed by saxagliptin (26.56%), sitagliptin (20.76%), linagliptin (0.25%), and alogliptin (0.12%). A statistically significant inconsistency was noted in some comparisons. CONCLUSIONS: The risk of HF needs to be taken into account when prescribing DPP-4 inhibitors. Evidence suggests that vildagliptin may be the least harmful agent with regard to the risk of HF. However, a statistically significant inconsistency was identified in the Bayesian network meta-analysis. Therefore, further studies are warranted to evaluate the cardiovascular safety of DPP-4 inhibitors.