Mechanism of lncRNA-H19/IGF1R regulating autophagy of brain microvascular endothelial cells after hypertensive intracerebral hemorrhage

Objective:To analyze the expression characteristics of lncRNA-H19(H19)in patients with hypertensive intracerebral hemorrhage (HICH) and explore the mechanism of H19 affecting autophagy and oxygen and glucose deprivation (OGD) injury of human brain microvascular endothelial cells (HBMECs).Methods:Blood samples of healthy people, hypertension patients and HICH patients were collected.The lncRNA array chip was used to detect the expression profile of lncRNA, and real-time fluorescence quantitative polymerase chain reaction(RT-qPCR)was used to detect the expression level of H19.The relationship between H19 expression and the amount of cerebral hemorrhage and NIHSS score was analyzed.The target protein of H19 was predicted, its mRNA expression level was detected by RT-qPCR, and its correlation with H19 was analyzed.HBMECs with knockdown or overexpression of H19 and its interacting proteins were treated with OGD.Autophagy was detected by immunofluorescence.Autophagy related proteins(LC3-Ⅰand LC3-Ⅱ), hypoxia inducible factor-1α(HIF-1α)and vascular endothelial growth factor(VEGF)were detected by western blotting.Results:The level of H19 in patients with HICH was significantly higher than that in healthy people (t=0.021, P< 0.05) and patients with hypertension(t=0.018, P< 0.05).The level of H19 increased with the increase of HICH grade, and was positively correlated with the amount of cerebral hemorrhage and NIHSS score (R²=0.087, R²=0.113, P< 0.05).The level of H19 in HBMECs increased with the increase of OGD treatment time(t=0.023, P< 0.05).IGF1R mRNA level in patients with HICH was lower than that in healthy controls people (t=0.015, P< 0.05), and decreased with the aggravation of HICH (t=0.043, P< 0.05).There was a negative correlation between H19 and IGF1R in patients with HICH (R²=0.187, P< 0.05).OGD treatment decreased the level of IGF1R protein in HBMECs, but knockdown of H19 increased IGF1R protein in OGD-HBMECs.In OGD-HBMECs, LC3 autophage, LC3-Ⅱ/LC3-Ⅰ, HIF-1α and VEGF decreased by knockdown of H19 or overexpression of IGF1R, but increased by overexpression of both IGF1R and H19 at the same time.Conclusion:H19 is related to HICH.Down regulation of H19 can increase IGF1R, and then futher alleviate OGD induced autophagy and injury of HBMECs.