| First Author | Riboulet-Chavey A | Year | 2008 |
| Journal | Diabetes | Volume | 57 |
| Issue | 2 | Pages | 415-23 |
| PubMed ID | 18003756 | Mgi Jnum | J:132308 |
| Mgi Id | MGI:3775681 | Doi | 10.2337/db07-0993 |
| Citation | Riboulet-Chavey A, et al. (2008) Inhibition of AMP-activated protein kinase protects pancreatic beta-cells from cytokine-mediated apoptosis and CD8+ T-cell-induced cytotoxicity. Diabetes 57(2):415-23 |
| abstractText | OBJECTIVE: Apoptotic destruction of insulin-producing pancreatic beta-cells is involved in the etiology of both type 1 and type 2 diabetes. AMP-activated protein kinase (AMPK) is a sensor of cellular energy charge whose sustained activation has recently been implicated in pancreatic beta-cell apoptosis and in islet cell death posttransplantation. Here, we examine the importance of beta-cell AMPK in cytokine-induced apoptosis and in the cytotoxic action of CD8(+) T-cells. RESEARCH DESIGN AND METHODS: Clonal MIN6 beta-cells or CD1 mouse pancreatic islets were infected with recombinant adenoviruses encoding enhanced green fluorescent protein (eGFP/null), constitutively active AMPK (AMPK-CA), or dominant-negative AMPK (AMPK-DN) and exposed or not to tumor necrosis factor-alpha, interleukin-1beta, and interferon-gamma. Apoptosis was detected by monitoring the cleavage of caspase-3 and DNA fragmentation. The cytotoxic effect of CD8(+) purified T-cells was examined against pancreatic islets from NOD mice infected with either null or the AMPK-DN-expressing adenoviruses. RESULTS: Exposure to cytokines, or expression of AMPK-CA, induced apoptosis in clonal MIN6 beta-cells and CD1 mouse pancreatic islets. By contrast, overexpression of AMPK-DN protected against the proapoptotic effect of these agents, in part by preventing decreases in cellular ATP, and lowered the cytotoxic effect of CD8(+) T-cells toward NOD mouse islets. CONCLUSIONS: Inhibition of AMPK activity enhances islet survival in the face of assault by either cytokines or T-cells. AMPK may therefore represent an interesting therapeutic target to suppress immune-mediated beta-cell destruction and may increase the efficacy of islet allografts in type 1 diabetes. |
