Effects of microRNA-29a on retinopathy of prematurity by targeting AGT in a mouse model.
BACKGROUND
This study aimed to explore the effects of microRNA-29a (miR-29a) on retinopathy of prematurity (ROP) by targeting angiotensinogen (AGT) expression in a mouse model.


METHODS
Ninety-six C57BL/6J mice were selected and divided into the normal control group (n = 12) and the oxygen-induced retinopathy (OIR) group (n = 84). All the mice in the OIR group were assigned to the following seven groups (12 mice in each group): the blank, miR-29a mimics, miR-29a inhibitors, empty plasmid, miR-29a mimics + si-AGT, miR-29a inhibitors + si-AGT and si-AGT groups. ADPase histochemical staining was conducted to detect the morphology of retinal neovascularization. H&E staining was performed to quantify retinal neovascularization. The qRT-PCR assay was applied to detect the expression levels of miR-29a and theAGTmRNA. Western blotting was used to detect the protein expressions of AGT, vascular endothelial growth factor (VEGF), hepatocyte growth factor (HGF), angiotensin (ANG) and angiotensin II (AngII).


RESULTS
Compared with the normal control group, miR-29a expression decreased, while theAGTmRNA expression and the protein expression levels of AGT, VEGF, HGF, ANG and AngII increased, and retinal vascular density and neovascularization also increased in the OIR group. In the OIR group, compared with the blank, empty plasmid, miR-29a inhibitors and miR-29a inhibitors + si-AGT groups, miR-29a expression increased, while theAGTmRNA expression and protein expression levels of AGT, VEGF, HGF, ANG and AngII decreased, and retinal vascular density and neovascularization also decreased in the miR-29a mimics, miR-29a mimics + si-AGT and si-AGT groups.


CONCLUSIONS
MiR-29a could inhibit retinal neovascularization to prevent the development and progression of ROP by down-regulating AGT.
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Xin-Ke
XK
Chen
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Li-Juan
LJ
Ouyang
Department of Ophthalmology, Southwest Hospital, Third Military Medical University Chongqing 400038, P. R. China.
Zheng-Qin
ZQ
Yin
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Yuan-You
YY
Xia
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Xiu-Rong
XR
Chen
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Hui
H
Shi
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Yan
Y
Xiong
Department of Ophthalmology, Children's Hospital of Chongqing Medical University Chongqing 400014, P. R. China.
Lian-Hong
LH
Pi
AGT; miRNA-29a; mouse model; retinopathy of prematurity