Long non-coding RNA Hottip modulates high-glucose-induced inflammation and ECM accumulation through miR-455-3p/WNT2B in mouse mesangial cells

Long non-coding RNAs (lncRNAs) play important roles in the pathogenesis of various diseases, including diabetic nephropathy (DN). However, the detailed mechanism is still largely unknown. High-glucose treated SV40-MES13 cells was used to mimic diabetic nephropathy in vitro. qRT-PCR was introduced to measure Hottip, collagen type I (Col. I), collagen type IV (Col. IV), fibronectin (FN), PAI-1, miR-455-3p and Wnt2B, IL-6, TNF-α mRNA level. Ellisa was used to examine the expression level of IL-6, TNF-α in the cell culture medium. Western blotting was employed to detect the protein level of Col. I, Col. IV, FN, PAI-1, Wnt2B, β-catenin and cyclin D1. Cell viability was examined by MTT assay, luciferase reporter assay were used to determine the relationship between Hottip, miR-455-3p and Wnt2B. In the results, Hottip and Wnt2B was upregulated in db/db DN mice and high-glucose treated mouse mesangial cells (MMCs) while miR-455-3p was downregulated. High glucose treatment could enhance cell proliferation, and inflammation, increase fibrosis-related protein expression and active Wnt2B/β-catenin/cyclin D1 pathway, while Hottip silencing reversed all the effects caused by high-glucose treatment. miR-455-3p was a sponge target of Hottip while Wnt2B was a downstream target of miR-445-3p. miR-445-3p inhibitor could suppress the effect of Hottip knockdown in cell proliferation, inflammation and fibrosis-related protein expression. Our data supported lncRNA Hottip/miR-455-3p/Wnt2B axis plays an important role in cell proliferation, inflammation, and extracellular matrix (ECM) accumulation in diabetic nephropathy.