Chaves Míriam Martins, Costa Daniela Caldeira, Souza Denniece Adriana da Costa, Lima e Silva Francisco das Chagas, Machado José Augusto Nogueira
Departamento de Bioquímica e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais - Caixa Postal 486, 30161-970, Belo Horizonte, Minas Gerais, Brazil.
Curr Aging Sci. 2008 Mar;1(1):51-5. doi: 10.2174/1874609810801010051.
Diabetes is associated with a pro-inflammatory status characterized by an increased production of inflammatory molecules. Reactive oxygen species (ROS) and cAMP elevating agents represent two molecular systems, normally generated during inflammation. These molecules could be responsible for the alteration of signaling pathways. In the present paper we have studied the correlation between ROS generation and inositolpolyphosphates (InsP(1), InsP(2) InsP(3) and InsP(4)) released by granulocytes from Type 1 diabetic patients (DM1) in the presence or in the absence of cyclic AMP-elevating agents.
The effect of cAMP on ROS production was quantified in a chemoluminescence assay luminol-dependent (RLU/min). InsP(1), InsP(2) InsP(3) and InsP(4) were quantified by inositol-H(3) in a Beta-counter and the results were expressed as count per minute (CPM).
The elevation of intracellular level of cAMP inhibited both InsP(3) and ROS production in granulocytes from healthy subjects and activated in the cells from Type 1 diabetic patients. InsP(1), InsP(2) and InsP(4) did not show significant alteration in both studied cells. There was a significant correlation between InsP(3) and ROS in the presence of elevated content of cAMP. This correlation was observed in a 15 minutes reaction for healthy subjects and in 120 minutes for DM1.
The importance of both InsP(3) release and ROS production in an inflammatory process and tissue pathophysiology in Type 1 diabetic patients is still under debate because hyperglycemia accelerates generation of oxidative stress and may play an important role in the development of complications in diabetes. Thus, our results demonstrated alteration in metabolic response in granulocytes from Type 1 diabetic patients and it may be important for the development of therapeutic processes and drugs that interfere with signaling of ROS generation and may contribute to the improvement of the severe complications of diabetes.
糖尿病与以炎症分子产生增加为特征的促炎状态相关。活性氧（ROS）和环磷酸腺苷（cAMP）升高剂代表炎症过程中通常产生的两个分子系统。这些分子可能是信号通路改变的原因。在本文中，我们研究了在有或没有环磷酸腺苷升高剂存在的情况下，1型糖尿病患者（DM1）粒细胞释放的ROS产生与肌醇多磷酸盐（InsP(1)、InsP(2)、InsP(3)和InsP(4)）之间的相关性。
通过鲁米诺依赖性化学发光测定法（相对光单位/分钟）对cAMP对ROS产生的影响进行定量。通过β计数器中的肌醇-H(3)对InsP(1)、InsP(2)、InsP(3)和InsP(4)进行定量，结果以每分钟计数（CPM）表示。
健康受试者粒细胞中细胞内cAMP水平的升高抑制了InsP(3)和ROS的产生，并激活了1型糖尿病患者细胞中的这两种物质。InsP(1)、InsP(2)和InsP(4)在两种研究细胞中均未显示出显著变化。在cAMP含量升高的情况下，InsP(3)和ROS之间存在显著相关性。在健康受试者的15分钟反应和DM1的120分钟反应中观察到了这种相关性。
1型糖尿病患者炎症过程和组织病理生理学中InsP(3)释放和ROS产生的重要性仍存在争议，因为高血糖会加速氧化应激的产生，并且可能在糖尿病并发症的发展中起重要作用。因此，我们的结果表明1型糖尿病患者粒细胞的代谢反应发生了改变，这对于开发干扰ROS产生信号的治疗方法和药物可能很重要，并且可能有助于改善糖尿病的严重并发症。
