Abstract: Objective: To investigate the regulation effect of endogenous nicotinamide phosphoribosyl transferase (Nampt) on the Vimentin expression of glomerular cells in high concentration glucose,and to clarify the mechanism of formation of diabetic kidney inflammation fibrosis. Methods: The C57/BL6 diabetic mice were selected and the kidney tissues were collected, and the wild C57/L86 mice were used as control group;the pathological section and tissue fluorescence staining were performed.The expression and location of endogenous Nampt and Vimentin in the glomerular cells were detected by immuno-focused technology. The HBZY-1 cells were randomly divided into 4 groups:low concentration of glucose (LG, 0.56 mmol·L^-1) control group,high concentration glucose (HG, 200 mmol·L^-1) group,HG + FK866 group and HG+nicotinamide mononucleotide (NMN) group.In HG group, the cells were treated with FK866 (10 μmol·L^-1) and NMN (1 mmol·L^-1) for 24 h after cultured with HG for 5 d. The expression levels of Nampt, Vimentin, nuclear factor-kappa B p65 (NF-κBp65) and sirtuin type 1 (Sirt1) were detected by immunofluorescence and Western blotting methods. The expression levels of Nampt and Vimentin were detected by RT-PCR and Western blotting methods. Results: The shape and size of glomerulus had obvious atrophy of the mice in severe diabetic group compared with normal C57/BL6 mice group. The expression level of Vimentin in glomerular cells was increased with the increasing of endogenous Nampt (P<0.01). When the HBZY-1 cells were cultured in HG condition,the exprssion levels of Nampt, Vimentin and NF-kB p65 were obviously increased while the Sirt1 expression levels was significantly decreased compared with control group (P<0.01).The expression levels of Nampt, Vimentin and NF-κB p65 in glomerular cells in HG+FK866 HG+NMN groups were singnificartyly decreased compared with control group (P<0.01). Conclusion: The endogenous Nampt over-expression in glomerular cells can enhance the expression of Vimentin under high concentration of glucose stress through NF-κBp65 and Sirt1 signal pathway.

Key words: high concentration of glucose, nicotinamide phosphoribosyltransferase, sirtuin type 1, vimentin, nuclear factor-kappa Bp65