Exploring the Use of Antioxidant Scavengers and Mesothelioma Asbestos Disease

Comparing and contrasting the various research into Mesothelioma disease brings some startling results.  One interesting study is called, "Oxygen radicals and asbestos-mediated disease." By T R Quinlan, J P Marsh, Y M Janssen, P A Borm, and B T Mossman - Environ Health Perspect. 1994 December; 102(Suppl 10): 107–110.  Here is an excerpt: " Abstract - Asbestos fibers are potent elaborators of active oxygen species whether by reactions involving iron on the surface of the fiber, or by attempted phagocytosis of fibers by cell types resident in the lung. The link between production of active oxygen species and the pathogenesis of asbestos-mediated disease has been highlighted by studies outlined here exploring the use of antioxidant scavengers which inhibit the cytotoxic effects of asbestos both in vitro and in vivo. The use of antioxidant enzymes ameliorates the induction of certain genes necessary for cell proliferation, such as ornithine decarboxylase, implicating oxidants as causative factors in some abnormal cell replicative events. Based on these observations, antioxidant enzymes likely represent an important lung defense mechanism in response to oxidative stress. In addition, their gene expression in lung or in cells from bronchoalveolar lavage might be a valuable biomarker of chronic inflammation and pulmonary disease after inhalation of oxidants."

Another interesting study is called, "Radiographic abnormalities in asbestos insulators: Effects of duration from onset of exposure and smoking. Relationships of dyspnea with parenchymal and pleural fibrosis" by R. Lilis MD, A. Miller MD, J. Godbold PhD, E. Chan MS, I. J. Selikoff MD - American Journal of Industrial Medicine volume 20, issue 1, pages 1-15- 1991 – here is an excerpt: "Abstract - Chest radiographs and spirometry were evaluated in 2,907 active and retired asbestos insulators; most (86.8%) had ≥ 30 years from onset of asbestos exposure. Testing was performed in 19 cities in the United States during 1981–1983. Complete demographic, smoking, clinical, and radiologic data were obtained for 2,790 workers. This is the largest single group of insulators that has been studied. Five hundred forty-eight (19.7%) had never smoked cigarettes, 942 (33.9%) were current cigarette smokers, and 1,300 (46.6%) were ex-smokers. Only 439 (15.7%) workers had no radiographic evidence of asbestos-related disease (normal chest X-ray); 668 (23.9%) had pleural fibrosis only, 325 (11.6%) had parenchymal fibrosis alone, and 1,358 (48.7%) had both parenchymal and pleural fibrosis. The prevalence of radiographic parenchymal changes increased significantly (p < .001) from 38.6% (DURONSET < 30 years) to 70% (≥40 years). For pleural changes the comparative prevalences were 55% and 82%. Those with no history of cigarette smoking were more likely to have normal filMS than those with a history of smoking (19.2% versus 14.4% for current smokers and 15.2% among ex-smokers), and were less likely to have parenchymal fibrosis (44.5% versus 69.7% for current smokers and 60.2% of ex-smokers). Dyspnea, MRC grade 3 and higher, was more prevalent when pleural fibrosis was associated with interstitial pulmonary fibrosis (at all profusion levels of small opacities) than when pleural fibrosis was absent. Logistic regression analysis of factors contributing to such dyspnea showed that the presence of combined parenchymal and pleural abnormalities was a significant explanatory variable, in addition to age, smoking, and body mass (Quetelet index); the presence of parenchymal changes only or of pleural changes only, as factors contributing to dyspnea, did not reach the level of statistical significance in the regression analysis. The results of these examinations show that pleural fibrosis is a frequent finding in asbestos-exposed groups with long-term follow-up and that its functional significance is not negligible. The contribution of cigarette smoking to prevalence and severity of interstitial fibrosis is an additional reason for smoking cessation among asbestos-exposed individuals."

A third study is called, "Asbestos: a chronology of its origins and health effects." By R Murray - Br J Ind Med 1990;47:361-365.  Here is an excerpt: "Abstract - The emotionalised subject of asbestos is treated in chronological terms: how the "magic mineral" known in ancient times in Europe and Asia became in the late nineteenth century an important industrial resource of particular interest to the navies of the world; and how its malign effects gradually became apparent during the present century. The media have made asbestos a notorious villain, but it still has properties and applications useful to society if they are properly controlled in the same way as other industrial hazards. One important application is the manufacture of asbestos cement pipes which are a convenient and cheap method of providing water supplies and sewage disposal for developing countries. An appeal is made for prudence and not hysteria in relation to the use of mineral fibres of all types."

We all owe a debt of gratitude to these fine researchers for their important work.  If you found any of these excerpts helpful, please read the studies in their entirety.