Cardile Venera, Proietti Lidia, Panico Annamaria, Lombardo Laura
Department of Physiological Sciences, University of Catania, Catania, Italy.
Oncol Rep. 2004 Dec;12(6):1209-15.
In the present study, we investigated the involvement of NO in the cytotoxic and genotoxic effects caused by fluoro-edenite in mouse monocyte-macrophage cell line J774. Fluoro-edenite is a new asbestos-like amphibole present in the benmoreitic lavas recently extracted from stone quarries in Biancavilla, a village located in the Etnean Volcanic Complex (Catania, Italy) of eastern Sicily, in which an epidemiological survey evidenced a cluster of cases of the mortality due to pleural mesothelioma. Fluoro-edenite appears as a probable carcinogenic agent. Nitrite and nitrate concentration (NO) in the supernatant was quantified by colorimetric assay based on the Griess reaction and iNOS (inducible nitric oxide synthetase) expression was determined by immunostaining in mouse monocyte-macrophage cell line J774 treated with different concentrations of fluoro-edenite (5, 50 and 100 microg/ml) for 24, 48, 72 and 96 h. Parallel experiments were performed treating the cultures also with lipopolysaccharides (LPS), used as inflammation-inducing molecule. In our experimental conditions, fluoro-edenite did not modify the level of NO and the expression of iNOS at the experimental used concentrations for 24, 48 and 72 h. These parameters were significantly modified at the higher doses (50 and 100 microg/ml) of fluoro-edenite for 96 h and were further more increased, in concentration- and time-dependent manner, when cell cultures were treated with fluoro-edenite and LPS. These findings provide convincing evidence that NO is involved in the fluoro-edenite-induced cytotoxicity and geno-toxicity in mouse monocyte-macrophage cell line J774 when the fiber remain for longer times and particularly in cultures treated with LPS, demonstrating that inflammatory disorders appear to increase the risk for lung cancer induced by fluoro-edenite probably by the involvement of NO.
在本研究中，我们调查了一氧化氮（NO）在氟直闪石对小鼠单核巨噬细胞系J774产生的细胞毒性和遗传毒性作用中的参与情况。氟直闪石是一种新的石棉样闪石，存在于最近从西西里岛东部埃特纳火山复合体（意大利卡塔尼亚）比安卡维拉的采石场开采的本莫尔岩熔岩中，在该地区的一项流行病学调查证实了一组因胸膜间皮瘤导致的死亡病例。氟直闪石似乎是一种可能的致癌剂。通过基于格里斯反应的比色法对上清液中的亚硝酸盐和硝酸盐浓度（NO）进行定量，并通过免疫染色法测定用不同浓度（5、50和100微克/毫升）的氟直闪石处理24、48、72和96小时的小鼠单核巨噬细胞系J774中诱导型一氧化氮合酶（iNOS）的表达。同时进行平行实验，用脂多糖（LPS）处理培养物，LPS用作炎症诱导分子。在我们的实验条件下，在24、48和72小时的实验使用浓度下，氟直闪石未改变NO水平和iNOS的表达。在氟直闪石的较高剂量（50和100微克/毫升）处理96小时时，这些参数发生了显著改变，并且当细胞培养物用氟直闪石和LPS处理时，它们以浓度和时间依赖性方式进一步增加。这些发现提供了令人信服的证据，即当纤维停留较长时间时，尤其是在用LPS处理的培养物中，NO参与了氟直闪石诱导的小鼠单核巨噬细胞系J774中的细胞毒性和遗传毒性，表明炎症紊乱似乎可能通过NO的参与增加了氟直闪石诱导肺癌的风险。
