Inhalation of Talc Induces Infiltration of Macrophages and Upregulation of Manganese Superoxide Dismutase in Rats

Abstract

Talc is a mineral that is widely used in cosmetic products, antiseptics, paints, and rubber manufacturing. Although the toxicological effects of talc have been studied extensively, until now no detailed inhalation study of talc focusing on oxidative stress has been done. This repeated 4 weeks whole-body inhalation toxicity study of talc involved Sprague-Dawley rats. Male and female groups of rats were exposed to inhaled talc at 0, 5, 50, and 100 mg/m(3) for 6 hours daily, 5 days/week for 4 weeks. The objective was to identify the 4-week inhalation toxicity of talc and investigate antioxidant activity after exposure to talc. There were no treatment-related symptoms or mortality in rats treated with talc. Glucose (GLU) was decreased significantly in male rats exposed to 50 and 100 mg/m(3) of talc. Histopathological examination revealed infiltration of macrophages on the alveolar walls and spaces near the terminal and respiratory bronchioles. In male and female rats exposed to 100 mg/m(3) talc, expression of superoxide dismutase 2, a typical biological indicator of oxidative damage, was significantly increased. Thus, inhalation of talc induces macrophage aggregations and oxidative damage in the lung.

Systematic review of the scientific evidence of the pulmonary carcinogenicity of talc

“…Similar findings were reported in rats exposed to non-asbestiform talcum powder for 6 h per day for 4 weeks via whole-body inhalation ( 28 ). The authors observed increases in macrophage infiltration at 50 and 100 mg/m 3 talc, but not at the lowest concentration of 5 mg/m 3 .…”

Oxidative stress and cytotoxic effects of silver ion in mouse lung macrophages J774.1 cells

“…Oxidative stress is induced when excessive ROS overwhelm the antioxidant defense system. This system is composed of non-enzymatic antioxidants such as ascorbic acid (vitamin C), alpha-tocopherol (vitamin E) and GSH, and enzymatic antioxidants such as superoxide dismutase, catalase and glutathione peroxidase (Birben et al, 2012;Shim et al, 2015;Valko et al, 2015). GSH is an important intracellular antioxidant that scavenges ROS, thus preventing inflammation and cell damage (Chaufan et al, 2014;Tajima et al, 2010).…”

High Content Image Analysis as a Tool to Morphologically Distinguish Macrophage Activation and Determine Its Importance for Foamy Alveolar Macrophage Responses

“…The NR8383 cell line was chosen for this study as it provides a homogenous source of highly responsive alveolar macrophages ( 11 , 12 ). Moreover, it is an established and well characterized alveolar macrophage cell line with appropriate culture characteristics and suitable as comparator cell line for in vivo alveolar macrophage responses observed in the Sprague-Dawley rat model ( 11 , 12 ). The cell line was obtained from LGC Standards (cat#AgC11x3A, Teddington, Middlesex, UK) and used between passage numbers 2 and 20 from purchase.…”