LncRNA AK094457 promotes AngII-mediated hypertension and endothelial dysfunction through suppressing of activation of PPARγ

Hypertension is one of the major risk factors for cardiovascular disease worldwide and is striking more young people, which is characterized by impaired vascular endothelial function. To find the functional lncRNAs associated with hypertension, high throughput lncRNA microarray were used to analyze expression profile of the lncRNAs in the aortic vascular endothelial cells (VECs) of spontaneously hypertensive rats (SHRs). The tail vein injection of siRNA was used to study the influence of lncRNA AK094457 inhibition on endothelial function in vivo. In vitro, endothelial function was studied in endothelial cells transfected with lncRNA AK094457-overexpressed vectors and siRNAs. pPPARγ and iNOS protein levels were detected with Western blot. Elisa assay was used to analyze the secretion of AngII, ET-1, ROS and LDH level. The nitrite/nitrate (NO₂^-/NO₃^-) concentration was measured using a colorimetric assay. LncRNA AK094457 was a most upregulated lncRNA in SHRs. It is showed that downregulation of AK094457 significantly reduced rat arterial pressure, increased activation of endothelial PPARγ, and suppressed serum contents of AngII and NO in vivo. Furthermore, results from gain-and-loss of function in primary aortic endothelial cells indicated that AK094457 negatively regulated activation of PPARγ and promoted AngII-mediated endothelial dysfunction, manifested by decreased capacities of cell proliferation and migration, and increased levels of ROS production and LDH release. In conclusion, lncRNA AK094457 is identified as a key regulator in blood pressure and endothelial function, which can increase AngII-induced hypertension and endothelial dysfunction via suppression of PPARγ.