Distributional characteristics of sulfated glycosaminoglycans in normal human nasal mucosa and nasal polyp.

The results of this study suggest that an altered expression pattern of sulfated glycosaminoglycans (GAGs) in nasal polyp may not function as a charge restriction barrier for vascular permeability, contributing to the leakage of protein and fluid. Sulfated GAGs are found on the vascular endothelial surface and in the extracellular matrix in various tissues and organs, suggesting that these materials constitute a negatively charged screen restricting the movement of circulating plasma molecules. This study was designed to elucidate the distributional characteristics of sulfated GAGs in normal human nasal mucosa and nasal polyp in order to understand their roles in the formation of nasal polyp. The expression and localization of sulfated GAGs in normal human nasal mucosa and nasal polyp were detected light microscopically with the histochemical method using poly-L-lysine-conjugated colloidal gold followed by silver enhancement. Sulfated GAGs in normal human nasal mucosa were distributed in the epithelial layer, vascular endothelial surface, submucosal gland and extracellular matrix. In nasal polyp, intense staining was also seen in the glandular structure and epithelial layer. However, the vascular endothelium and extracellular matrix exhibited either a weak reaction or no reaction.

Expression and distribution of thioredoxin and thioredoxin reductase in human nasal mucosa and nasal polyp.

CONCLUSIONS: The results of this study indicate that thioredoxin (Trx) and thioredoxin reductase (TrxR) may play a role in the defense of normal human nasal mucosa against external noxious stimuli. Based on the fact that normal nasal mucosa is continuously exposed to inhaled toxicants and contains a considerable number of inflammatory cells, Trx and TrxR may be upregulated even in normal nasal mucosa and perhaps the difference in their expression levels between normal nasal mucosa and nasal polyp, if it exists at all, is small and therefore difficult to detect. Further studies will be needed to clarify the roles of Trx and TrxR in the pathogenesis of nasal polyp. OBJECTIVES: The cellular antioxidant defense system includes thiol-containing proteins such as Trx and TrxR, which have recently attracted much attention due to their strong antioxidant radical quenching capabilities and other important biological functions related to the regulation of the cellular redox state. This study was undertaken to investigate the expression and distribution of Trx and TrxR in normal human nasal mucosa and nasal polyp, and to improve understanding of the significance of the Trx system in these conditions. MATERIAL AND METHODS: The expression and distribution of Trx and TrxR in normal human inferior turbinate mucosa and nasal polyp were investigated using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR, Western blotting and immunohistochemistry. RESULTS: mRNAs and protein for both Trx and TrxR were detected in normal human inferior turbinate mucosa and nasal polyp. Semiquantitative RT-PCR and Western blotting revealed that there was no significant difference in the expression levels of Trx and TrxR between inferior turbinate mucosa and nasal polyp. Immunoreactivity for both Trx and TrxR was seen in nasal epithelial cells, glands and vascular endothelium of inferior turbinate mucosa and nasal polyp. Trx and TrxR immunoreactivity was also found in inflammatory infiltrating cells in inferior turbinate mucosa and nasal polyp.

Expression and distribution of ion transport mRNAs in human nasal mucosa and nasal polyps.

CONCLUSIONS: Our results indicate that the electrogenic kidney Na(+)/HCO(3)(-) cotransporter (kNBC), KCl cotransporter (KCC1 and -4) and Ca(2+)-activated Cl(-) channel (CaCC1, -2, -3) mRNAs are expressed in normal nasal mucosa and nasal polyp, suggesting that altered expression of all CaCC mRNAs in nasal polyp may cause impaired electrolyte and water transport across the epithelial cells. OBJECTIVE: Electrolyte transport by nasal epithelia has been suggested to be important for controlling the quantity and composition of the nasal fluid and may play an important role in the development of nasal polyps. Transepithelial transport of ions and water in various fluid-transporting epithelia is strictly dependent on the localization of specific membrane proteins in the polarized epithelial cells. In this study we investigated the expression and distribution of mRNA transcripts for kNBC, pancreatic NBC, KCC1, -2, -3, -4 and CaCC1, -2, -3 gene families in human nasal mucosa and nasal polyp. MATERIAL AND METHODS: The expression and localization of these gene families were investigated in inferior turbinate tissues and nasal polyp using reverse transcriptase polymerase chain reaction (RT-PCR), semiquantitative RT-PCR and in situ hybridization. RESULTS: mRNAs for kNBC, KCC1 and -4 and all the CaCC families (CaCC1, -2 and -3) are expressed in human turbinate mucosa and nasal polyp. The expression levels of kNBC and KCC1 and -4 mRNAs did not differ between nasal mucosa and nasal polyp. However, the expression levels of all the CaCC genes were significantly decreased in nasal polyp. In situ hybridization revealed that the expression of these genes was mainly localized in the epithelial layer and submucosal glands of inferior turbinate mucosa and in the epithelial layer of nasal polyp.