HuR deficiency in exosome abrogates high glucose-induced inflammatory and fibrogenesis response in fibroblasts

To confirm the relevance of paracrine mechanism of HuR-mediated effects in target cells, we performed HuR loss-of-function studies. We knockdown HuR in macrophage cell line (RAW 264.7 cells) using lentiviral-based shRNA against HuR, treated with HG, isolated and transferred exosomes to fibroblasts and evaluated its effects on inflammatory and fibrogenesis signaling.
Our observation: As compared to fibroblasts (FB) incubated with HG-treated wild-type macrophages-derived exosomes (ExoWT), fibroblasts incubated with HuR-deficient exosomes from HG-treated macrophages (ExoHuR KD) show reduction in mRNA expression of IL1β, TNFα, TGFβ, MMP9, COL1A1, COL1A2, COL3A1 and αSMA, suggesting lower inflammatory and fibrogenesis response.