MiR-449b-5p Ameliorates Hypoxia-induced Cardiomyocyte Injury through Activating PI3K/AKT Pathway by Targeting BCL2L13.

Recent reports show miR-449b-5p reduces liver and renal ischemia/reperfusion (I/R) injury, but its effects on hypoxia-induced cardiomyocyte injury in ischemic heart disease are still unknown. In this study, AC16 human cardiomyocytes underwent hypoxic conditions for durations of 24, 48, and 72 h. We observed that miR-449b-5p expression was significantly downregulated in hypoxic AC16 cardiomyocytes. Elevating the levels of miR-449b-5p in these cells resulted in enhanced cell survival, diminished release of LDH, and a reduction in cell apoptosis and oxidative stress using CCK-8, LDH assays, flow cytometry, TUNEL staining, and various commercial kits. Conversely, reducing miR-449b-5p levels resulted in the opposite effects. Through bioinformatics analysis and luciferase reporter assays, BCL2-like 13 (BCL2L13) was determined to be a direct target of miR-449b-5p. Inhibiting BCL2L13 greatly inhibited hypoxia-induced cell viability loss, LDH release, cell apoptosis, and excessive production of oxidative stress, whereas increasing BCL2L13 negated miR-449b-5p's protective impact in hypoxic AC16 cardiomyocytes. Additionally, miR-449b-5p elevated the levels of the proteins p-PI3K, p-AKT, and Bcl-2, while decreasing Bax expression in hypoxic AC16 cardiomyocytes by targeting BCL2L13. In summary, the research indicates that the protective effects of miR-449b-5p are facilitated through the activation of the PI3K/AKT pathway, which promotes cell survival, and by targeting BCL2L13, which inhibits apoptosis, offering a potential therapeutic strategy for ischemic heart disease by mitigating hypoxia-induced cardiomyocyte injury.

Risk Prediction Model Based on Biomarkers of Remodeling in Patients with Acute Anterior ST-Segment Elevation Myocardial Infarction.

BACKGROUND The aim of the present study was to develop a risk prediction model in patients with acute anterior ST-segment elevation myocardial infarction (STEMI). MATERIAL AND METHODS Clinical data from 333 patients with acute anterior STEMI were retrospectively analyzed. Clinical echocardiographic and angiographic data from patients with left ventricular remodeling (LVR) and those without LVR were compared. Factors that influenced risk were identified using multivariate logistic regression analysis. The area under the curve (AUC) of the receiver operating characteristic curve was used to assess the diagnostic performance of the model. RESULTS After 6-month follow-up, 135 of the patients experienced LVR (LVR group), whereas 198 did not (non-LVR group). Results of multivariate analysis showed that the number of stenosed coronary vessels, left ventricular end-diastolic volume (LVEDV), left ventricular ejection fraction (LVEF), transforming growth factor-beta (TGF-ß) at admission, and cardiac troponin I 3 days after admission (3-d cTnI) were all factors predictive of LVR in patients with acute anterior STEMI (all P<0.05). The established prediction model was Y=-20.639+0.711×number of stenosed coronary vessels + 0.137×LVEDV-0.129×LVEF+0.026×TGF-ß at admission + 0.162×3-d cTnI. The estimated AUC of this model was 0.978 (95% confidence interval [CI] 0.955-0.991), significantly superior to the single-factor numbers for stenosed coronary vessel of 0.650 (95% CI 0.597-0.702), LVEDV of 0.876 (95% CI 0.836-0.910), LVEF of 0.684 (95% CI 0.631-0.734), TGF-ß at admission of 0.696 (95% CI 0.644-0.745), cTnI at admission of 0.913 (95% CI 0.877-0.941), and 3-d cTnI of 0.945 (95% CI 0.914-0.967). CONCLUSIONS The established model had excellent diagnostic accuracy for predicting LVR in patients with acute anterior STEMI.

MicroRNA-197 promotes proliferation and inhibits apoptosis of gallbladder cancer cells by targeting insulin-like growth factor-binding protein 3.

BACKGROUND: Gallbladder cancer (GBC) is one of the common malignant tumors of the biliary tract. There is no report that miR-197 is involved in GBC. OBJECTIVES: The relationship between miR-197 expression and survival time of GBC patients was analyzed. Furthermore, the role and mechanism of miR-197 in GBC was explored. MATERIAL AND METHODS: A total of 39 GBC patients (21 males, 18 females; average age 56.1 ±8.5 years) were included from December 2013 to November 2014. All patients were admitted to our hospital for surgical treatment (excluding patients with preoperative chemotherapy). The expression of miR-197 in GBC tissues was examined, and the relationship between miR-197 and patient survival time was analyzed. Cell Counting Kit-8 (CCK-8) and colony formation assays were used to detect cell proliferation. Flow cytometry and TUNEL staining were used to detect apoptosis. Expressions of proteins related with proliferation and apoptosis were detected. The target of miR-197 was predicted through bioinformatics website and verified using the dual luciferase reporter gene assay. The target gene was interfered to so that the effect of miR-197 on the regulation of GBC cell proliferation and apoptosis could be observed. RESULTS: MiR-197 was highly expressed in GBC tissues, and the expression was closely related to the poor prognosis of GBC. Downregulation of miR-197 inhibited the proliferation and promoted the apoptosis of GBC cells; it also decreased the expressions of proliferation-related proteins p-ERK1/2 and p-AKT, and increased that of apoptosis pathway-related proteins Bax/Bcl-2 and c-caspase-3. The upregulation of miR-197 induced an opposite trend. MiR-197 directly regulated IGFBP3. CONCLUSIONS: Our study proved that the expression of miR-197 is closely related to the poor prognosis of GBC. The miR-197-IGFBP3 axis regulates the proliferation and apoptosis of GBC cells. Downregulation of miR-197 inhibited the proliferation and promoted the apoptosis of GBC cells, indicating potential therapeutic effects.

Down-regulation of microRNA-429 alleviates myocardial injury of rats with coronary heart disease.

In recent years, the impact of microRNAs (miRNAs) on coronary heart disease (CHD) has been identified. This study was aimed to investigate the regulative role of microRNA (miR-429) in myocardial injury of rats with CHD. Expression of miR-429 in CHD patients and healthy people was detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR). The CHD rat models were injected with normal saline, mimics negative control (NC), miR-429 mimics, inhibitors NC and miR-429 inhibitors twice a week, for 4 weeks. Levels of inflammatory factors, oxidative stress indices as well as apoptosis of cardiomyocytes were determined by a series of assays. Expression of miR-429 was up-regulated in CHD patients. Reduced miR-429 could decline the expression of oxidative stress-related factors and inflammation-related factors, and inhibit the apoptosis of cardiomyocytes in rats with CHD. Moreover, the down-regulation of miR-429 could promote the expression of CrkL and repress activation of the MEK/ERK signaling pathway. This study reveals that restrained miR-429 could exert a protective impact on myocardial injury of rats with CHD by suppressing oxidative stress, inflammation reaction and apoptosis of cardiomyocytes. The function mechanisms may relate to the up-regulation of CrkL and inhibition of the MEK/ERK signaling pathway.

Overexpression of GAS5 inhibits abnormal activation of Wnt/ß-catenin signaling pathway in myocardial tissues of rats with coronary artery disease.

OBJECTIVE: The aim of this study is to investigate the clinical value of long noncoding RNA growth arrest-specific transcript 5 (LncRNA GAS5) in the diagnosis of coronary artery disease (CAD) and its protective effect on myocardial injury in rats with CAD. METHODS: Patients with CAD and healthy controls were selected to measure the expression of GAS5, and further to perform the correlation analysis and ROC curve. In addition, the rat models of CAD were also established to observe the effect of GAS5 on hyperlipidemia, myocardial injury, cardiomyocyte apoptosis, oxidative stress, and inflammatory injury of rats with CAD, and the effect of the Wnt/ß-catenin signaling pathway was also determined. RESULTS: Overexpression of GAS5 in CAD rats determines improvement of hyperlipidemia, attenuation of myocardial injury, inhibition of cardiomyocyte apoptosis, oxidative stress, inflammatory injury, and abnormal activation of the Wnt/ß-catenin signaling pathway in myocardial tissues. CONCLUSION: Our study demonstrates that downregulation of GAS5 is found in CAD, and overexpression of GAS5 inhibits abnormal activation of the Wnt/ß-catenin signaling pathway in myocardial tissues of CAD rats.

Association between the M235T polymorphism of the AGT gene and cytokines in patients with hypertension.

The aim of the present study was to explore the association between the M235T polymorphism of the angiotensinogen (AGT) gene and cytokines in patients with essential hypertension (EH). A total of 300 patients with EH and an age-matched control group of 150 individuals without EH, secondary hypertension, myocardial infarction and diabetes were enrolled in this study. Polymerase chain reaction combined with restriction fragment length polymorphism (PCR-RFLP) was used to detect variation in the target genotype, and enzyme-linked immunosorbant assay (ELISA) was used to detect the cytokine [interleukin (IL)-1, IL-6 and tumor necrosis factor-α (TNF-α)] concentrations. The AGT gene 235T allele and 235TT genotype frequencies in hypertensive patients were slightly higher than those in the controls. Furthermore, in the hypertensive subjects with the AGT gene 235T allele, the concentrations of IL-1 and TNF-α were significant higher than those in the controls. The results from our study suggest that the higher AGT gene TT genotype and 235T allele frequencies may be risk factors for hypertension. High frequencies of the AGT gene 235T allele and high cytokine concentrations (IL-1 and TNF-α) may promote the transcription and expression of AGT, particularly in hypertensive patients with the 235TT genotype.