LncRNA LINC00961 regulates endothelial­mesenchymal transition via the PTEN­PI3K­AKT pathway.

The long noncoding RNA LINC00961 plays a crucial role in cancer and cardiovascular diseases. In the present study, the role and underlying mechanism of LINC00961 in endothelial­mesenchymal transition (EndMT) induced by transforming growth factor beta (TGF­ß), was investigated. Human cardiac microvascular endothelial cells were transfected with LV­LINC00961 or short hairpin LINC00961 plasmids to overexpress or knock down LINC00961 in the cells, respectively. The cells were then exposed to TGF­ß in serum­free medium for 48 h to induce EndMT. Flow cytometric analysis, Cell Counting Kit­8 assay and immunofluorescence staining were performed to examine the cell apoptosis rate, assess cell viability, and identify CD31+/α­SMA+ double­positive cells, respectively. Western blotting and reverse transcription­ quantitative polymerase chain reaction were used to evaluate protein and mRNA expression, respectively. Injury to endothelial cells and EndMT was induced by TGF­ß in a time­dependent manner. LINC00961 overexpression promoted injury and EndMT, whereas LINC00961 knockdown had the opposite effects. Knockdown of LINC00961 attenuated EndMT and injury to endothelial cells induced by TGF­ß via the PTEN­PI3K­AKT pathway. Inhibition of LINC00961 expression may prevent the occurrence of EndMT­related cardiovascular diseases, such as myocardial fibrosis and heart failure. Therefore, LINC00961 shows potential as a therapeutic target for cardiovascular diseases.

LncRNA SNHG12 alleviates hypertensive vascular endothelial injury through miR-25-3p/SIRT6 pathway.

The objective of this study was to find the role of LncRNA SNHG12 in the regulation of hypertensive vascular endothelial injury. LncRNA SNHG12 and miR-25-3p expression were detected by quantitative RT-PCR. Protein levels of Sirtuin 6 (SIRT6), endothelial cell (EC) senescence markers p16 and p21, and EC marker CD31 were measured by Western blot. The apoptosis of HUVECs was detected by flow cytometry. The binding between LncRNA SNHG12 and miR-25-3p was verified by dual luciferase reporter gene assay and RNA pull-down assay. As a result, LncRNA SNHG12 was down-regulated in aortic primary ECs isolated from Ang II-induced hypertensive mice and 1 kidney/deoxycorticosterone acetate/salt-induced hypertensive mice. In Ang II-treated HUVECs, the expression level of SNHG12 was reduced and the overexpression of SNHG12 inhibited EC senescence markers p16 and p21 expressions, the apoptosis of HUVECs, and caspase-3 activity. Further investigation confirmed that LncRNA SNHG12 bound to miR-25-3p, and negatively regulated miR-25-3p expression. MiR-25-3p directly targeted SIRT6 and negatively regulated SIRT6 expression. In addition, SNHG12 overexpression inhibited Ang II-induced HUVECs injury through regulating miR-25-3p. Finally, in vivo experiments showed LncRNA SNHG12 overexpression alleviated vascular endothelial injury in Ang II-induced hypertensive mice. In conclusion, LncRNA SNHG12 alleviates vascular endothelial injury induced by hypertension through miR-25-3p/SIRT6 pathway.

Molecular mechanisms in microRNA-mediated TRB3 gene and hypertension left ventricular hypertrophy.

The present study investigated the relationship between microRNA-mediated TRB3 gene and hypertension left ventricular hypertrophy at the molecular level. Polymorphic site in TRB3 gene was identified by direct PCR method, and the correlation between the SNP site and ventricular hypertrophy was determined. MicroRNAs target gene sequence interacting on the TRB3 polymorphic site was screened by bioinformatics, and the effect of microRNAs on the TRB3 polymorphic site was finally verified by luciferase test. Two polymorphic sites rs6186912 and rs6186923 were found in the TRB3 gene, and the direct relationship between rs6186923 polymorphic site and the hypertension left ventricular hypertrophy in patients with myocardial hypertrophy was compared and analyzed. Pictar software was used to analyze the effect of miR-100 on rs6186923, and the argumentation was verified by luciferase test. In conclusion, the study showed that the TRB3 gene polymorphism rs6186923 was able to affect the TRB3 gene by affecting the binding of miR-100, which indirectly caused the formation of hypertension left ventricular hypertrophy.

Oestradiol ameliorates monocrotaline pulmonary hypertension via NO, prostacyclin and endothelin-1 pathways.

Pulmonary hypertension continues to be a serious clinical problem with high mortality. As oestrogen is a potential vasodilator of the pulmonary circulation, this study examined the mechanisms by which 17ß-oestradiol improves monocrotaline (MCT)-induced pulmonary hypertension. Female Sprague-Dawley rats underwent bilateral ovariectomy or sham operations. The rats received MCT (50 mg·kg(-1)) and were treated with 17ß-oestradiol (1 mg·kg(-1) per day) for either 5 weeks or only from week 4 to week 5. Plasma 17ß-oestradiol concentrations were decreased in sham-operated, MCT-treated rats when compared with sham-operated rats (17.7 ± 4.7 versus 50.3 ± 15.4 pg·mL(-1); p=0.029). The 17ß-oestradiol anabolic enzyme cytochrome P450 (CYP)-19 was decreased by MCT treatment, while the catabolic enzymes CYP-1A1 and -1B1 were increased. Ovariectomised and MCT-treated rats had more severe pulmonary hypertension. 17ß-oestradiol suppressed pulmonary arterial smooth muscle cell proliferation and macrophage infiltration, and enhanced apoptosis by increasing nitric oxide (NO) and prostacyclin (prostaglandin (PG)I2) levels and reducing endothelin (ET)-1 levels. Phosphoinositide-3-kinase (PI3K) and Akt phosphorylations were markedly increased, but were inhibited by 17ß-oestradiol treatment in rats with pulmonary hypertension. Oestrogen deficiency may aggravate development of pulmonary hypertension. 17ß-oestradiol improved pulmonary hypertension via activation of the PI3K/Akt pathway to regulate NO, PGI2 and ET-1 expression.

[Effects of transforming growth factor-beta1 on rat cardiocyte hypertrophy].

AIM: To investigate the effects of transforming growth factor-beta1 (TGF-beta1) and signal protein Smad3 on rat myocardial hypertrophy. METHODS: The total protein was analysed by flow cytometer assay to judge the hypertrophy of myocardial cell incubated with different level of TGF-beta1 in cultured myocardial cells of neonatal rats. The models of rat cardiac hypertrophy were produced with constriction of the abdominal aorta. At the different time after the operation, the rats were killed, and the left ventricular mass indexes (LVMl) were investigated. The mRNA expressions of TGF-beta1 and Smad3 of cultured cells and hypertrophic left ventricles were assessed by RT-PCR, the protein expressions of Smad3 were assessed by Western blot. RESULTS: In cultured neonatal myocardial cells, different level TGF-beta1 could significantly increase the total protein, and TGF-beta1 (3 ng/ml) could increase the expression of mRNA and protein of Smad3 and continued for 8 h of cultured cardiomyocytes. The LVMI and the expression of TGF-beta1 mRNA and Smad3 mRNA/protein of hypertrophic left ventricle were increased at the 3rd day after the operation and continued for 4 weeks. The peak expression of them was in 2 weeks after operation. CONCLUSION: TGF-beta1 has the effects on rat myocardial hypertrophy, signal protein Smad3 is included in the pathologic progress of rat myocardial hypertrophy.