miRNA-451a regulates RPE function through promoting mitochondrial function in proliferative diabetic retinopathy

Area of Science:

• Ophthalmology
• Molecular Biology
• Cell Biology

Background:

• Diabetic retinopathy (DR) is a leading cause of vision loss, characterized by abnormal retinal cell proliferation.
• MicroRNAs (miRNAs) are implicated in the pathogenesis of various diseases, including DR.
• The specific role of microRNA-451a (miR-451a) in DR and its molecular targets remain to be fully elucidated.

Purpose of the Study:

• To investigate the role of miR-451a in diabetic retinopathy (DR).
• To identify the downstream targets and molecular mechanisms of miR-451a in regulating retinal pigment epithelial (RPE) cells.
• To explore the therapeutic potential of miR-451a in DR.

Main Methods:

• Analysis of epiretinal membrane samples from proliferative diabetic retinopathy (PDR) patients.
• Quantification of miR-451a expression in Akita mice retinas and RPE cells under diabetic conditions using qRT-PCR.
• Bioinformatic prediction, dual luciferase assay, qRT-PCR, and Western blotting to identify and validate miR-451a targets.
• Cell proliferation, migration, and mitochondrial function assays following miR-451a mimic/inhibitor transfection.

Main Results:

• miR-451a expression was downregulated in PDR patient samples, Akita mice retinas, and diabetic RPE cells.
• Activating transcription factor 2 (ATF2) was identified as a direct target of miR-451a.
• miR-451a inhibited RPE cell proliferation and migration, and enhanced mitochondrial function.
• Overexpression of miR-451a downregulated ATF2 and its downstream targets (CyclinA1, CyclinD1, MMP2).

Conclusions:

• miR-451a plays a crucial role in regulating RPE cell proliferation and migration via the miR-451a/ATF2 pathway.
• miR-451a positively impacts mitochondrial function in the context of diabetic conditions.
• The miR-451a/ATF2 axis presents a promising therapeutic target for proliferative diabetic retinopathy.