Insulin-Attenuated Inflammatory Response of Dendritic Cells in Diabetes by Regulating RAGE-PKCβ1-IRS1-NF-κB Signal Pathway: A Study on the Anti-Inflammatory Mechanism of Insulin in Diabetes

Figure 4

Role of RAGE in the AGEs-BSA-stimulated BMDCs immune maturation. (a) Flow cytometric analysis was performed for cell surface CD83, CD86, and MHC-II expression examinations. RAGE neutralizing antibody attenuated AGEs-BSA-induced upregulation of CD83 and CD86. (b) The concentrations of TNF-α, IFN-γ, IL-6, IL-1b, and CCL2 in the supernatants of the culture were measured by ELISA; (c, d) The expressions of cytokines and chemokines mRNA in BMDCs were analyzed by real-time quantitative RT-PCR. Secretion of cytokines and chemotactic factors was all reversed by RAGE neutralizing antibody; (e) The expressions of NF-κB, IκB, and phosphorylated PKCβ1 were determined by western blot in the presence or absence of anti-RAGE neutralizing antibody. The phosphorylation of IκB, NF-κB, and PKCβ1 induced by AGEs-BSA decreased after treated with anti-RAGE neutralizing antibody. Besides, anti-RAGE neutralizing antibody also inhibit the phosphorylation of IκB, NF-κB, and PKCβ1 without AGEs-BSA. Data are expressed as ; ; vs. control group; ^# vs. AGEs-BSA group. AGEs-BSA: advanced glycosylation end-bovine serum albumin; BMDCs: bone marrow-derived dendritic cells; RAGE: receptor for advanced glycation end products; pPKC: phosphorylated protein kinase C; TNF-α: tumor necrosis factor-α; IFN-γ: interferon-γ; MHC-II: major histocompatibility complex-II; NF-κB: nuclear factor-κB.

(a)

(b)

(c)

(d)

(e)