New insights into the role of zinc in the respiratory epithelium

Abstract

Summary Over the past 30 years, many researchers have demonstrated the critical role of zinc (Zn), a group IIb metal, in diverse physiological processes, such as growth and development, maintenance and priming of the immune system, and tissue repair. This review will discuss aspects of Zn physiology and its possible beneficial role in the respiratory epithelium. Here we have detailed the mechanisms by which Zn diversely acts as: (i) an antioxidant; (ii) an organelle stabilizer; (iii) an anti-apopototic agent; (iv) an important cofactor for DNA synthesis; (v) a vital component for wound healing; and (vi) an anti-inflammatory agent. This paper will also review studies from the authors' laboratory concerning the first attempts to map Zn in the respiratory epithelium and to elucidate its role in regulating caspase-3 activated apoptosis. We propose that Zn, being a major dietary anti-oxidant has a protective role for the airway epithelium against oxyradicals and other noxious agents. Zn may therefore have important implications for asthma and other inflammatory diseases where the physical barrier is vulnerable and compromised.

Zinc deficiency or excess within the physiological range increases genome instability and cytotoxicity, respectively, in human oral keratinocyte cells

“…Low cellular Zn concentration was found to induce programmed cell death in various cell types including fibroblasts, hepatocytes, T-cell precursors, glioma and testicular cells (Ho and Ames 2002;Ho et al 2003;Yan et al 2008;Bao and Knoell 2006;Yamaguchi et al 2009). In addition, Zn depletion has also been associated with caspase activation and increases in apoptosis in airway epithelial cells, lung and hepatocytes (Truong-Tran et al 2001;Hennig et al 1999). Under low Zn conditions, Caspase 3 was reported to be involved in apoptosis induction via the intrinsic cell death pathway (Clegg et al 2005).…”

Zinc Deficiency Mediates Alcohol-Induced Alveolar Epithelial and Macrophage Dysfunction in Rats

“…Although considerable information is available on the role of zinc in the brain, the liver, the immune system, and the musculoskeletal system, relatively fewer studies have focused on its role in the lungs. One notable exception is work by Zalewski and colleagues demonstrating a critical role for zinc in maintaining the health of the large airways, and how zinc deficiency may contribute to the pathophysiology of reactive airway diseases such as asthma (13,14,16,17,27). It was recently reported (28) that human ZIP 8 is up-regulated at the onset of inflammation, thereby importing zinc into the cells and facilitating cytoprotection of the lung epithelial cells.…”

Early detection and treatment of Speckled leukoplakia

“…11 Zinc may also play a role in the activation of metalloproteinase enzymes that play a role in the process of collagenase. 12 The administration of multivitamin containing vitamin B complex, vitamin E and vitamin C, and zinc, moreover, aims to help the wound heal process. Vitamins E and C have antioxidant and anti-inflammatory effects on the wound healing process.…”