Acid Sphingomyelinase Inhibitors Normalize Pulmonary Ceramide and Inflammation in Cystic Fibrosis
Acid Sphingomyelinase Inhibitors Normalize Pulmonary Ceramide and Inflammation in Cystic Fibrosis
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DOI：
10.1165/rcmb.2009-0174oc
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发表时间：
2010-06-01
影响因子：
6.4
通讯作者：
Gulbins, Erich
中科院分区：
文献类型：
--
作者：
Becker, Katrin Anne;Riethmueller, Joachim;Gulbins, Erich
采用遗传小鼠模型，我们最近表明，神经酰胺的积累是至关重要的参与囊性纤维化（CF）肺病的发病机制。酸性鞘磷脂酶（Asm）的遗传或全身抑制对于患者的治疗是不可行的，或者可能引起不良反应。因此，必须开发一种在CF小鼠肺中特异性地操纵神经酰胺的方法。我们测试了吸入不同的酸性鞘磷脂酶抑制剂是否会降低CF小鼠肺中Asm活性和神经酰胺蓄积。确定药物的有效性和特异性。神经酰胺测定质谱法，DAG-激酶测定，荧光显微镜。我们测定了肺和全身Asm活性、中性鞘磷脂酶（NSM）、神经酰胺、细胞因子和感染易感性。质谱、DAG激酶测定和半定量免疫荧光显微镜检查显示，标准饮食不会影响支气管呼吸道上皮细胞中的神经酰胺，而含有Peptamen的饮食严重影响CF肺中鞘脂的浓度。吸入Asm抑制剂阿米替林、曲米帕明、地昔帕明、氯普噻吨、氟西汀、曲马多或舍曲林可恢复小鼠支气管上皮细胞中的正常神经酰胺浓度，减少CF小鼠肺部炎症，并预防铜绿假单胞菌感染。所有药物均显示出非常相似的疗效。吸入药物无全身效应，也不抑制NSM。这些发现采用了几种结构不同的Asm抑制剂，将Asm确定为肺中降低神经酰胺浓度的主要靶点。吸入Asm抑制剂可能是CF的有益治疗，具有最小的全身不良反应。
Employing genetic mouse models we have recently shown that ceramide accumulation is critically involved in the pathogenesis of cystic fibrosis (CF) lung disease. Genetic or systemic inhibition of the acid sphingomyelinase (Asm) is not feasible for treatment of patients or might cause adverse effects. Thus, a manipulation of ceramide specifically in lungs of CF mice must be developed. We tested whether inhalation of different acid sphingomyelinase inhibitors does reduce Asm activity and ceramide accumulation in lungs of CF mice. The efficacy and specificity of the drugs was determined. Ceramide was determined by mass spectrometry, DAG-kinase assays, and fluorescence microscopy. We determined pulmonary and systemic Asm activity, neutral sphingomyelinase (Nsm), ceramide, cytokines, and infection susceptibility. Mass spectroscopy, DAG-kinase assays, and semiquantitative immune fluorescence microscopy revealed that a standard diet did not influence ceramide in bronchial respiratory epithelial cells, while a diet with Peptamen severely affected the concentration of sphingolipids in CF lungs. Inhalation of the Asm inhibitors amitriptyline, trimipramine, desipramine, chlorprothixene, fluoxetine, amlodipine, or sertraline restored normal ceramide concentrations in murine bronchial epithelial cells, reduced inflammation in the lung of CF mice and prevented infection with Pseudomonas aeruginosa. All drugs showed very similar efficacy. Inhalation of the drugs was without systemic effects and did not inhibit Nsm. These findings employing several structurally different Asm inhibitors identify Asm as primary target in the lung to reduce ceramide concentrations. Inhaling an Asm inhibitor may be a beneficial treatment for CF, with minimal adverse systemic effects.