The lethal effects of cytokine-induced nitric oxide on cardiac myocytes are blocked by nitric oxide synthase antagonism or transforming growth factor beta.
The lethal effects of cytokine-induced nitric oxide on cardiac myocytes are blocked by nitric oxide synthase antagonism or transforming growth factor beta.
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一氧化氮合酶拮抗剂或转化生长因子β可阻断细胞因子诱导的一氧化氮对心肌细胞的致命作用。
DOI：
10.1172/jci117713
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发表时间：
1995
期刊：
影响因子：
--
通讯作者：
Cannon,PJ
中科院分区：
文献类型：
--
作者：
Pinsky,DJ;Cai,B;Yang,X;Rodriguez,C;Sciacca,RR;Cannon,PJ
巨噬细胞产生的诱导型一氧化氮 (NO) 对入侵生物体具有细胞毒性，在宿主防御中发挥重要作用。最近的研究表明，心脏内可诱导产生一氧化氮，并且细胞因子诱导的一氧化氮介导心肌收缩力的改变，但一氧化氮对心脏的细胞毒性潜力尚未确定。为了评估诱导型一氧化氮合酶 (iNOS) 对心肌细胞毒性的作用，我们将成年大鼠心肌细胞暴露于单独的细胞因子或共培养中的活化的 J774 巨噬细胞。在用 IFN γ 和 LPS 处理的 J774 巨噬细胞以及用 TNF-α、IL-1 β 和 IFN γ 处理的心肌细胞中观察到 iNOS 信息和蛋白质的表达增加。通过增加亚硝酸盐的产生，在共培养物和分离的肌细胞制剂中证实了NO合成的增加。 NO 合成的增加与心肌细胞死亡的平行增加有关，这可以通过 CPK 释放到培养基中以及通过台盼蓝染色观察到的膜完整性丧失来测量。在培养基中添加竞争性NO合酶抑制剂L-NMMA可以防止在分离的心肌细胞和共培养实验中细胞因子处理后观察到的亚硝酸盐产量增加和细胞毒性。由于转化生长因子 β 调节其他细胞类型中的 iNOS 表达，因此我们评估了其对心肌细胞 iNOS 表达和 NO 介导的心肌细胞细胞毒性的影响。 TGF-β 减少心肌细胞 iNOS 信息和蛋白质的表达，减少亚硝酸盐的产生，并同时减少 NO 介导的细胞毒性。总而言之，这些实验显示了心脏内内源性 NO 产生的细胞毒性潜力，并表明 TGF-β 或 NO 合酶拮抗剂在减弱这些致命作用方面发挥着作用。这些发现可能有助于解释心脏对脓毒症或同种异体移植排斥的反应，以及不同病因的扩张型心肌病的进展。
Inducible nitric oxide (NO) produced by macrophages is cytotoxic to invading organisms and has an important role in host defense. Recent studies have demonstrated inducible NO production within the heart, and that cytokine-induced NO mediates alterations in cardiac contractility, but the cytotoxic potential of nitric oxide with respect to the heart has not been defined. To evaluate the role of inducible nitric oxide synthase (iNOS) on cardiac myocyte cytotoxicity, we exposed adult rat cardiac myocytes to either cytokines alone or to activated J774 macrophages in coculture. Increased expression of both iNOS message and protein was seen in J774 macrophages treated with IFN gamma and LPS and cardiac myocytes treated with TNF-alpha, IL-1 beta, and IFN gamma. Increased NO synthesis was confirmed in both the coculture and isolated myocyte preparations by increased nitrite production. Increased NO synthesis was associated with a parallel increase in myocyte death as measured by CPK release into the culture medium as well as by loss of membrane integrity, visualized by trypan blue staining. Addition of the competitive NO synthase inhibitor L-NMMA to the culture medium prevented both the increased nitrite production and the cytotoxicity observed after cytokine treatment in both the isolated myocyte and the coculture experiments. Because transforming growth-factor beta modulates iNOS expression in other cell types, we evaluated its effects on cardiac myocyte iNOS expression and NO-mediated myocyte cytotoxicity. TGF-beta reduced expression of cardiac myocyte iNOS message and protein, reduced nitrite production, and reduced NO-mediated cytotoxicity in parallel. Taken together, these experiments show the cytotoxic potential of endogenous NO production within the heart, and suggest a role for TGF-beta or NO synthase antagonists to mute these lethal effects. These findings may help explain the cardiac response to sepsis or allograft rejection, as well as the progression of dilated cardiomyopathies of diverse etiologies.Images