主催: The Japanese Pharmacological Society, The Japanese Society of Clinical Pharmacology
会議名: WCP2018 (18th World Congress of Basic and Clinical Pharmacology)
開催地: Kyoto
開催日: 2018/07/01 - 2018/07/06
Background: PAQR3, also known as RKTG (Raf kinase trapping to Golgi), is localized at the Golgi apparatus with a seven-transmembrane helices and belongs to progesterone and adipoQ receptor (PAQR) family. Recent evidences suggest that inflammatory fibrosis acts as an important pathological characteristic in diabetic nephropathy (DN), and PAQR3 has effects on insulin resistance, glucose and lipid metabolism and inflammation. Therefore, we are highly concerned whether PAQR3 regulates the inflammatory fibrosis to ameliorate renal diabetic nephropathy. We aimed to observe the effects of PAQR3 on the NF-kappa B signaling pathway and expressions of fibronectin (FN) and intercellular adhesionmolecule-1 (ICAM-1), and its regulatory role in glomerular mesangial cells (GMCs) induced by high glucose (HG).
Method: To investigate the role of PAQR3 in regulating inflammatory
fibrosis of DN via NF-kappa B pathway, we performed assays of
transfection of PAQR3 plasmids and small-interfering RNA, and analyzed the protein expressions of FN and ICAM-1, the nuclear translocation and DNA binding activity of NF-kappa B, as well as the interaction between PAQR3 and β kinase of IκB (IKKβ) with means of western blotting (WB), dual luciferase reporter assay, electrophoretic mobility shift assay (EMSA) and immunoprecipitation (IP) in GMCs.
Results: The following findings were obtained: (1) PAQR3 protein level
was increased after HG treatment in a time-dependent manner in GMCs (2)PAQR3 overexpression dramatically raised FN and ICAM-1 expressions. When depletion of PAQR3 further declined the production of FN and ICAM-1 (3) PAQR3 overexpression promoted the nuclear accumulation, DNA binding activity, and transcriptional activity of NF-kappa B (4) The IP results showed that PAQR3 interacted with the IKKβ, and the interaction between PAQR3 and IKKβ was weakened by HG stimulation.
Conclusion: PAQR3 might boost the translocation of IKKβ into cytoplasm, thus accelerating the nuclear accumulation of NF-kappa B and regulating the expressions of FN and ICAM-1, ultimately exacerbating renal fibrosis in diabetes
