Here our focus was to study the role of RAGE in mouse mesangial cells (MMC) and the role of miRNAs in RAGE signaling. Methods: We analysed the expression of mRNA and miRNA related to fibrosis, inflammation and cell survival in MMCs from RAGE knock out (KO) using real time PCR. Treatments included TGF-β and HMGB1 under conditions of either
high glucose or low glucose. We performed similar analyses of gene and miRNA expression in RAGE KO mice following restoration of either membranous (full-) RAGE or soluble (ES-) RAGE using adenovirus delivery. Results: Surprisingly, several profibrotic (Collagen I, PAI-1, aSMA, VEGF, SNAIL, SLUG, ZEB2, TWIST, TGF-b receptor, Vimentin) and proinflammatory genes (MCP-1, IL-6) were upregulated in RAGE KO compared to wild type MMCs, while other extracellular matrix (ECM) components (Fibronectin, Laminin, Collgen IVa3) were not altered or downregulated by PLX4032 solubility dmso either low or high glucose. miR-192 and miR-29 family were significantly up regulated while miR-200 family were significantly downregulated. Interestingly, the expression of genes and microRNAs altered in RAGE KO MMCs compared to wild type BGJ398 concentration was largely restored by adenoviral delivery of either full or ES-RAGE. Conclusion: RAGE appears to have a homeostatic role in renal tissue by regulating
the expression of profibrotic, proinflammatory and cell survival genes, potentially via regulating the expression of certain miRNA. As a result, treatments for patients with diabetic nephropathy which involve direct targeting of RAGE need to be carefully monitored given the important role of RAGE in innate immunity and renal homeostasis. Treatments which mimic ES-RAGE may be a better option rather than targeting full length RAGE. LEE WEN-CHIN, CHEN CHIU-HUA, LEE LUNG-CHIH, LEE CHIEN-TE, CHEN JIN-BOR Division of Nephrology, Glutamate dehydrogenase Department of Internal
Medicine, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan Introduction: Mitochondrial morphogenesis and autophagy are two novel fields of research in diabetic kidney disease (DKD). The interplay of these two mechanisms in DKD remains unclear. Key proteins required for mitochondrial fusion include mitofusin 1 (MFN1) and mitofusin 2 (MFN2) and those for mitochondrial fission include dynamin related protein (DRP1) and FIS1. This study aimed to investigate the roles of mitochondrial morphogenesis and autophagy in DKD. We also aimed to treat the glucose-induced renal injuries by shaping the mitochondria. Methods: Diabetic mice were induced by high fat high sucrose (HFHS) diet. Immunohistochemistry was employed to delineate the expression patterns of Mfn1, Mfn2, Drp1 and Fis1 in mice kidneys. Cell (HK2) culture models were used to investigate the function of mitochondrial fusion/fission proteins.