Evidence for the involvement of cGMP and protein kinase G in nitric oxide‐induced apoptosis in the pancreatic B‐cell line, HIT‐T15

FEBS Letters

Loweth, Anne C²  Williams, Gwyn T²  Morgan, Noel G²  Scarpello, John H.B¹ 

[1] Cellular Pharmacology Group, Department of Medicine, Keele University, Staffordshire, ST5 5BG, UK;Cellular Pharmacology Group, Department of Biological Sciences, Keele University, Staffordshire, ST5 5BG, UK

关键词: Pancreatic B-cell;    Guanidine cyclase;    Protein kinase G;    Apoptosis;    Nitric oxide;    GC;    guanylyl cyclase;    GSNO;    S-nitrosoglutathione;    iNOS;    inducible nitric oxide synthase;    NO;    nitric oxide;    ODQ;    1H-[1;    2;    4]oxadiazolo[4;    3-a]quinoxalin-1-one;    PKG;    cGMP-dependent protein kinase;   

DOI  :  10.1016/S0014-5793(96)01392-0

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Intracellular production of nitric oxide (NO) is thought to mediate the pancreatic B-cell-directed cytotoxicity of cytokines in insulin-dependent diabetes mellitus, and recent evidence has indicated that this may involve induction of apoptosis. A primary effect of NO is to activate soluble guanylyl cyclase leading to increased cGMP levels and this effect has been demonstrated in pancreatic B-cells, although no intracellular function has been defined for islet cGMP. Here we demonstrate that the NO donor, GSNO, induces apoptosis in the pancreatic B-cell line HIT-T15 in a dose- and time-dependent manner. This response was significantly attenuated by micromolar concentrations of a specific inhibitor of soluble guanylyl cyclase, ODQ, and both 8-bromo cGMP (100 μM) and dibutyryl cGMP (300 μM) were able to fully relieve this inhibition. In addition, incubation of HIT-T15 cells with each cGMP analogue directly promoted cell death in the absence of ODQ. KT5823, a potent and highly selective inhibitor of cGMP-dependent protein kinase (PKG), abolished the induction of cell death in HIT cells in response to either GSNO or cGMP analogues. This effect was dose-dependent over the concentration range of 10–250 nM. Overall, these data provide evidence that the activation of apoptosis in HIT-T15 cells by NO donors is secondary to a rise in cGMP and suggest that the pathway controlling cell death involves activation of PKG.

【 授权许可】

Unknown