Targeting PCSK9, APOB, and CETP at the Transcriptome Level by hsa-miR-30b-3p Reduces LDL-Associated Protein in Huh-7...

Hypercholesterolemia is a common metabolic disorder characterized by elevated low-density lipoprotein cholesterol (LDL-C) levels, a major risk factor for cardiovascular disease. MicroRNAs (miRNAs) are key post-transcriptional regulators of gene expression and lipid metabolism.

In this study, in silico analysis revealed that miR-30b-3p could potentially target Apolipoprotein B (APOB), Proprotein convertase subtilisin/kexin type 9 (PCSK9), and Cholesteryl ester transfer protein (CETP). miR-30b-3p binding sites in the 3'-untranslated regions (UTRs) of PCSK9, APOB, and CETP were predicted and validated by dual luciferase reporter assays. Luciferase assays indicated significant reducing reporter activity (PCSK9: 49%, APOB: 39%, CETP: 86%). miR-30b-3p overexpression decreased mRNA levels of PCSK9, APOB, and CETP, with reduced PCSK9/ApoB protein but unchanged CETP protein. miR-30b-3p could play a regulatory role in lipid metabolism by targeting PCSK9 and APOB, reducing LDL levels in hepatocytes. Huh-7 cells underwent miR-30b-3p overexpression via lentiviral transduction and the expression of genes/proteins were assessed by quantitative PCR and western blot. LDL and high-density lipoprotein (HDL)-associated proteins in the culture media supernatant were measured to evaluate functional lipid changes. LDL-associated protein decreased in the conditioned medium, whereas HDL-associated readouts remained unchanged, leading to a lower LDL/HDL ratio, indicating impact on lipid homeostasis.

This study aimed to investigate the effects of miR-30b-3p on the expression and function of the mentioned genes and the outcome of this intervention on lipid metabolism. These findings propose miR-30b-3p as a promising therapeutic candidate for hypercholesterolemia, warranting further in vivo validation.