Renal, vascular and cardiac fibrosis in rats exposed to passive smoking and industrial dust fibre amosite

Abstract

Passive smoking is an independent risk factor for cardiovascular diseases. Industrial fibrous dust, e.g. the asbestos group member, amosite, causes lung cancer and fibrosis. No data are available on renal involvement after inhalational exposure to these environmental pollutants or of their combination, or on cardiovascular and renal toxicity after exposure to amosite. Male Wistar rats were randomized into four groups (n= 6): control and amosite group received initially two intratracheal instillations of saline and amosite solution, respectively. Smoking group was subjected to standardized daily exposure to tobacco smoke for 2 hrs in a concentration resembling human passive smoking. Combined group was exposed to both amosite and cigarette smoke. All rats were killed after 6 months. Rats exposed to either amosite or passive smoking developed significant glomerulosclerosis and tubulointerstitial fibrosis. Combination of both exposures had additive effects. Histomorphological changes preceded the clinical manifestation of kidney damage. In both groups with single exposures, marked perivascular and interstitial cardiac fibrosis was detected. The additive effect in the heart was less pronounced than in the kidney, apparent particularly in changes of vascular structure. Advanced oxidation protein products, the plasma marker of the myeloperoxidase reaction in activated monocytes/macrophages, were increased in all exposed groups, whereas the inflammatory cytokines did not differ between the groups. In rats, passive smoking or amosite instillation leads to renal, vascular and cardiac fibrosis potentially mediated via increased myeloperoxidase reaction. Combination of both pollutants shows additive effects. Our data should be confirmed in subjects exposed to these environmental pollutants, in particular if combined.

Hypoxia: The Force that Drives Chronic Kidney Disease

“…41,42 In addition, rats exposed to either the asbestos group member amosite or to passive smoking develop significant glomerulosclerosis and tubulinterstitial fibrosis, and occupational exposure to silica, fiberglass, or solvents has been linked to an increased risk of developing ESRD. 35,214 Atherosclerosis Approximately six million Americans have combined atherosclerosis and kidney disease. 47 The development of atherosclerosis stems from multiple interactions among injurious stimuli and the healing or reparative responses of the arterial wall.…”

Risk factors for development of chronic kidney disease in cats

“…42 However, a longer term study of rats exposed to passive smoke at a concentration similar to human passive smoking, found significant histopathological evidence of glomerulosclerosis and tubulointerstitial fibrosis compared to control rats. 43 Results of the present study suggest that passive smoking is not an important risk factor for development of azotemia in cats. However, level of exposure could not be evaluated and dose-dependent studies may be required to determine any effect.…”

Previous Exposure to Cigarette Smoke Aggravates Experimental Cyclosporine-Induced Nephrotoxicity

“…In the same way, active cigarette smoking, passive CS exposure, and nicotine have each been associated with increased oxidative stress [25,26,27]. In the current study, the renal expression of nitrotyrosine, an indirect marker of nitrosative/oxidative stress, was significantly elevated only in rats treated with CsA and previously exposed to CS.…”

“…Myofibroblasts are a major source of collagen synthesis, and periglomerular myofibroblasts have been implicated in the development of glomerulosclerosis. Whereas CsA-induced chronic nephrotoxicity is not characterized by significant glomerular injury, cigarette smoking worsened glomerular structural injury in diabetic patients [29,30] and induced or worsened glomerular injury in rats and mice [15,22,26,27]. Nodular glomerulosclerosis was described in chronic smokers without known causes of glomerulosclerosis, suggesting a possible relationship with smoking [31].…”