Proteoglycan and collagen expression during human air conducting system development

Abstract

The lung is formed from a bud that grows and divides in a dichotomous way. A bud is a new growth center which is determined by epithelial-mesenchymal interactions where proteins of the extracellular matrix (ECM) might be involved. To understand this protein participation during human lung development, we examined the expression and distribution of proteoglycans in relation to the different types of collagens during the period in which the air conducting system is installed. Using light microscopy and immunohistochemistry we evaluate the expression of collagens (I, III and VI) and proteoglycans (decorin, biglycan and lumican) between 8 to 10 weeks post fertilization and 11 to 14 weeks of gestational age of human embryo and fetus lungs. We show that decorin, lumican and all the collagen types investigated were expressed at the epithelium-mesenchymal interface, forming a sleeve around the bronchiolar ducts. In addition, biglycan was expressed in both the endothelial cells and the smooth muscle of the blood vessels. Thus, the similar distribution pattern of collagen and proteoglycans in the early developmental stages of the human lung may be closely related to the process of dichotomous division of the bronchial tree. This study provides a new insight concerning the participation of collagens and proteoglycans in the epithelial-mesenchymal interface during the period in which the air conducting system is installed in the human fetal lung.

Reduction of MicroRNA-206 Contributes to the Development of Bronchopulmonary Dysplasia through Up-Regulation of Fibronectin 1

“…Among the approximately 800 candidate genes, FN 1 was one of the high-scoring candidates. FN 1 is an ECM component, and the ECM is critical for lung development [7,11]. FN 1 plays a major role in fundamental biological processes such as cell adhesion and migration, maintenance of normal cell morphology, cytoskeletal organization, and cell differentiation [12].…”

The human lung during the embryonic period: vasculogenesis and primitive erythroblasts circulation

“…The recent observation of the expression of collagens (I, III, VI) and biglycan, and its relation with blood vessel development during the human pseudoglandular period, has raised new questions regarding the mechanism involved in vascular network formation (Godoy‐Guzmán et al ). It has been shown that the vascular endothelial growth factor (VEGF) plays a significant role in vasculogenesis and angiogenesis, regulating vascular endothelial cell proliferation and differentiation (Neufeld et al ; Ferrara et al ).…”

“…The immunohistochemical analysis of lung tissue was performed according to Godoy‐Guzmán et al (). Briefly, sections were treated with 3% (v/v) H 2 O 2 in phosphate‐buffered saline (PBS) for 30 min to block endogenous peroxidase.…”

Expression of glial cells molecules in the optic nerve of adult dromedary camel (Camelus dromedarius): A histological and immunohistochemical analysis

“…Standard protocols of immunohistochemistry (IHC) (Garcia‐Martinez, Campos, & Godoy‐Guzman, ; Godoy‐Guzman, San Martin, & Pereda, ) and confocal immunofluorescence (Itoh, Itoh, Tassoni, & Ren, ; Sun et al, ) were performed as described earlier with minor modifications. For both methods, tissue sections of 5 μm thick were deparaffinized in xylene and rehydrated through graded sets of ethyl alcohol.…”