Effects of nano particles on antigen-related airway inflammation in mice

BACKGROUND: Particulate matter (PM) can exacerbate allergic airway diseases. Although health effects of PM with a diameter of less than 100 nm have been focused, few studies have elucidated the correlation between the sizes of particles and aggravation of allergic diseases. We investigated the effects of nano particles with a diameter of 14 nm or 56 nm on antigen-related airway inflammation. METHODS: ICR mice were divided into six experimental groups. Vehicle, two sizes of carbon nano particles, ovalbumin (OVA), and OVA + nano particles were administered intratracheally. Cellular profile of bronchoalveolar lavage (BAL) fluid, lung histology, expression of cytokines, chemokines, and 8-hydroxy-2'-deoxyguanosine (8-OHdG), and immunoglobulin production were studied. RESULTS: Nano particles with a diameter of 14 nm or 56 nm aggravated antigen-related airway inflammation characterized by infiltration of eosinophils, neutrophils, and mononuclear cells, and by an increase in the number of goblet cells in the bronchial epithelium. Nano particles with antigen increased protein levels of interleukin (IL)-5, IL-6, and IL-13, eotaxin, macrophage chemoattractant protein (MCP)-1, and regulated on activation and normal T cells expressed and secreted (RANTES) in the lung as compared with antigen alone. The formation of 8-OHdG, a proper marker of oxidative stress, was moderately induced by nano particles or antigen alone, and was markedly enhanced by antigen plus nano particles as compared with nano particles or antigen alone. The aggravation was more prominent with 14 nm of nano particles than with 56 nm of particles in overall trend. Particles with a diameter of 14 nm exhibited adjuvant activity for total IgE and antigen-specific IgG(1 )and IgE. CONCLUSION: Nano particles can aggravate antigen-related airway inflammation and immunoglobulin production, which is more prominent with smaller particles. The enhancement may be mediated, at least partly, by the increased local expression of IL-5 and eotaxin, and also by the modulated expression of IL-13, RANTES, MCP-1, and IL-6

Glandular Trichomes on the Leaves of Nicotiana tabacum: Morphology, Developmental Ultrastructure, and Secondary Metabolites

Glandular trichomes found on the surface of many higher plants contain specialized cells that produce and secrete copious amounts of particular secretory products. Leaf glandular trichomes of the non-model plant species Nicotiana tabacum represent a biologically active and stress-responsive tissue that contributes to plant defense response against biotic and abiotic stress and also influences leaf aroma and smoke flavor. Two morphologically different types of tobacco capitate trichomes, long- and short-stalked, with distinct functions, display ultrastructural features that are common to terpene-secreting glands, but only the secretory cells of the tall glandular trichomes are considered to be the site of biosynthesis of certain exudate compounds, including diterpenes and sucrose esters. Ultrastructural and histochemical characterization of tall glandular trichomes is described in an attempt to understand the contribution of these glands to the total secretion produced. Possible roles of distinct cellular compartments involved in the secretory process and secondary metabolite secretion under in vitro conditions are discussed.Gopal RK, Ekiert HM, Goyal S, editors. Plant Cell and Tissue Differentiation and Secondary Metabolites. Springer, Cham; 2020. p. 1–37. (Reference Series in Phytochemistry)