51. Suppression of TLR4 by miR-448 is involved in Diabetic development via regulating Macrophage polarization.
- Author
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Zhao Q, Wang X, Hu Q, Zhang R, and Yin Y
- Subjects
- Animals, Arginase metabolism, Cell Culture Techniques, Cell Polarity drug effects, Cell Polarity physiology, Chemokine CCL22 metabolism, Diabetes Mellitus, Experimental genetics, Diabetes Mellitus, Experimental pathology, Diabetes Mellitus, Type 2 genetics, Diabetes Mellitus, Type 2 pathology, Diet, High-Fat, Disease Models, Animal, Interferon-alpha metabolism, Interleukin-18 metabolism, Lipopolysaccharides pharmacology, Macrophage Activation, Macrophages, Peritoneal pathology, Male, Mice, Mice, Inbred C57BL, Nitric Oxide Synthase Type II metabolism, RAW 264.7 Cells, RNA genetics, RNA metabolism, Toll-Like Receptor 4 genetics, Transforming Growth Factor beta1 metabolism, Tumor Necrosis Factor-alpha metabolism, Diabetes Mellitus, Experimental metabolism, Diabetes Mellitus, Type 2 metabolism, Macrophages, Peritoneal metabolism, MicroRNAs metabolism, Toll-Like Receptor 4 metabolism
- Abstract
Objectives: Lipopolysaccharide (LPS) contributed to the development and progression of type 2 diabetes mellitus (T2D), while TLR4 is reported to mediate the LPS-induced inflammation in macrophages. However, the potential molecular mechanisms for TLR4-mediated macrophages activation in T2D have not yet to be fully clarified., Methods: Type 2 diabetes models in C57BL/6J mice were generated by a combination administration of streptozotocin (STZ) and a high-fat diet (HFD). Cell proportions of M1 and M2 macrophages were analyzed using flow cytometry. Expression profiles of miR-448 and TLR 4 were determined by qRT-PCR and Western blot., Key Findings: LPS/IFN-γ significantly induced M1 polarization in macrophages characterized by the increased levels of TNF-α, IL-6, IL-12, iNOS and decreased levels of TNF-β, CCL-22, IL-10 and Arg-1, with a higher expression of toll-like receptor 4 (TLR4) in vitro. Consistently, T2D mice-derived macrophages had a significantly elevated expression of TLR4 mRNA and decreased expression of miR-448. We further confirmed that miR-448 could inhibit TLR4 expression by targeting the 3'-UTR of TLR4, rescuing the LPS/IFN-γ-induced M1 macrophage polarization., Conclusions: Taken together, our results indicated that decreased miR-448 in diabetic macrophages may contribute to LPS-induced M1 polarization by targeting TLR4, thereby modulating T2D development., (© 2018 Royal Pharmaceutical Society.)
- Published
- 2019
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