Exosomes from high glucose-treated macrophages promote epithelial-mesenchymal transition of renal tubular epithelial cells via long non-coding RNAs.

BACKGROUND

Macrophages contribute to epithelial-mesenchymal transition (EMT) in diabetic nephropathy (DN). Exosomal long non-coding RNAs (lncRNAs) derived from macrophages play a major role in transmitting biological information, whereas related studies on DN are rare. Here we investigated the effects of exosomal lncRNAs from high glucose-treated macrophages on EMT.

METHODS

High glucose-treated macrophage exosomes (HG-exos) were extracted by coprecipitation and stabilized. Then, mouse renal tubular epithelial cells were treated with HG-exos for 24 h. Expression of E-cadherin, α-smooth muscle actin (α-SMA), and fibronectin was detected by western blotting, qPCR, and immunofluorescence. High-throughput sequencing was then applied to analyze the bioinformatics of HG-exos.

RESULTS

HG-exos inhibited the proliferation of tubular epithelial cells. Additionally, HG-exos markedly upregulated α-SMA and fibronectin expression and downregulated E-cadherin expression in tubular epithelial cells, indicating EMT induction. A total of 378 differentially expressed lncRNAs and 674 differentially expressed mRNAs were identified by high-throughput sequencing of HG-exos. Bioinformatics analysis and subsequent qPCR validation suggested 27 lncRNAs were enriched in the EMT-related MAPK pathway. Among them, ENSMUST00000181751.1, XR_001778608.1, and XR_880236.2 showed high homology with humans.

CONCLUSION

Exosomes from macrophages induce EMT in DN and lncRNAs in exosomes enriched in the MAPK signaling pathway may be the possible mechanism.