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-alpha mRNA level. Ellisa was used to examine the expression level of IL-6, INF-alpha in the cell culture medium. Western blotting was employed to detect the protein level of Col. I, Col. IV, FN, PAI-1, Wnt2B, beta-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/beta-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.