Mucins,a family of heavily glycosylated proteins,present mainly in epithelial cells.They function as essential barriers for epithelium and play important roles in cellular physiological processes.Aberrant expression and glycosylation of mucins in gastric epithelium occur at pathological conditions,such as Helicobacter pylori infection,chronic atrophic gastritis,intestinal metastasis,dysplasia,and gastric cancer.This review addresses the major roles played by mucins and associated O-glycan structures in normal gastric epithelium.Further,we expound the alterations of expression patterns and glycan signatures of mucins at those pathological conditions.
Gastric Mucosa/pathology* ; Glycosylation ; Helicobacter Infections/pathology* ; Helicobacter pylori/metabolism* ; Humans ; Mucins/metabolism* ; Stomach Neoplasms/pathology*

OBJECTIVETo explore a method which can remove the gastric mucus in order to prepare mucous membrane single cell suspension for the research of cytomics.

METHODSEnzymology was used to remove the mucus gel and to separate mucous layer from the normal fresh gastric tissue. The mucous layer was broken to prepare single cell suspension with machine method. Expression of major cyclins in mucous layer cells was examined by cytoimmunochemistry, flow cytometry(FCM) and confocal microscopy.

RESULTSThe 0.1% pepsin could dissolve the mucus gel and 1.2-2.4 U/L dispase could separate the mucous layer completely. The single mucous cell suspension was prepared successfully. FCM results from mucous single cell suspension revealed that expression of cyclin D(3), B(1) was obvious, that of cyclin D(2) was weak and that of cyclin D(1), A, E was the least. Similar results were found with confocal microscopy.

CONCLUSIONSSingle cell suspension from mucous layer can be easily prepared by pepsin and dispase. Cyclins schedule expression in vivo is different from cyclins schedule expression in vitro.

Cell Line ; Cell Proliferation ; Cyclins ; metabolism ; Flow Cytometry ; Gastric Mucins ; metabolism ; Gastric Mucosa ; cytology ; metabolism ; Humans ; Mucous Membrane ; cytology ; metabolism

PURPOSE: The goal of this study was to characterize the morphology of the mucinous layer on rabbit, bovine, owl, and human corneal endothelial cells. METHODS: Corneoscleral buttons were fixed using cetylpyridinium chloride to stabilize "mucus" and the tissue was prepared for transmission electron microscopy. Photomicrographs were measured to determine the thickness of the endothelial and epithelial mucinous layer in the central cornea. RESULTS: The endothelial mucinous layer was seen as a nearly uniform electrodense region on the apical aspect of the endothelium. It was found to be 0.9 microm, 0.9 microm, 0.9 microm, and 0.5 microm thick in rabbit, bovine, owl, and human, respectively. The owl endothelium had an additional less electrodense layer with a granular appearance and a thickness of about 200 microm. The mucinous layer on the epithelium was similar in appearance to that on the endothelium and across species. CONCLUSIONS: The morphologic similarity of the endothelial and epithelial mucinous layers is a serendipitous finding that should prove valuable in experimental design. Ultimately, it is hoped that studies of the posterior corneal surface will deepen our knowledge of endothelial protection.
Adult ; Animal ; Cytokines/pharmacology ; Endothelium, Corneal/ultrastructure ; Endothelium, Corneal/metabolism* ; Endothelium, Corneal/cytology ; Human ; Microscopy, Electron ; Mucins/ultrastructure ; Mucins/metabolism* ; Owls ; Rabbits ; Staining and Labeling

PURPOSE: To evaluate whether alterations in plasma vitamin A and E levels in patients with psoriasis have an effect on tear film changes. METHODS: Sixty-two eyes of 31 patients with psoriasis vulgaris (Group A) and 74 eyes of 37 age- and gender-matched control subjects (Group B) were included in the study. Ocular and medical histories and dietary habits were obtained from each patient. The tear film break-up time (TBUT), the Schirmer 1 test results and plasma vitamin A and E levels were evaluated. RESULTS: The mean Schirmer 1 test score was 14.76 +/- 6.12 mm/5 min in Group A and 15.69 +/- 3.10 mm/5 min in Group B. The mean plasma levels of vitamins A and E in Groups A and B were 1.86 +/- 0.62 micromol/L and 1.88 +/- 0.65 micromol/L vs. 26.21 +/- 5.13 micromol/L and 27.19 +/- 8.89 micromol/L, respectively. The Schirmer 1 test results and plasma vitamin A and E levels were not found to be significantly different between the groups (p > 0.05). The mean TBUT was 9.94 +/- 6.18 seconds in Group A and 14.47 +/- 5.65 seconds in Group B, a significant difference (p < 0.05). No correlation existed between plasma vitamin A and E levels, TBUT or the severity and duration of the disease (p > 0.05). CONCLUSIONS: Plasma vitamin A and E levels do not seem to be related to tear film changes in patients with psoriasis vulgaris.
Adolescent ; Adult ; Female ; Humans ; Male ; Middle Aged ; Mucins/*metabolism ; Psoriasis/*metabolism ; Tears/*metabolism ; Vitamin A/*blood ; Vitamin E/*blood ; Young Adult

In this study we investigate the expression pattern of mucin genes in the human testis and evaluate the relationship between the expression of mucin genes and impaired spermatogenesis in the human testis. Thirty human testis tissues were collected from patients undergoing diagnostic testicular biopsy to investigate the cause of infertility. One part of the tissue underwent histological observation, and the other part of the tissue was subjected to semiquantitative RT-PCR of mucin genes, that is, mucin1, 2, 3, 4, and 9. The relative amount of mucin mRNAs was calculated by densitometry using glyceraldehydes-3-phosphate dehydrogenase (GAPDH) as an internal control. The samples were histologically diagnosed as either obstructive azoospermia with normal spermatogenesis (n = 13) or non-obstructive azoospermia with impaired spermatogenesis (n = 17). In the human testis with normal spermatogenesis, mRNA expression of mucin1, 9, 13 and GAPDH were found, but RT-PCR products of mucin 2, 3 and 4 were not detected. In the testis with impaired spermatogenesis, however, RT-PCR product of mucin1 was not found. There was no difference in the other mucin mRNA expression patterns between the testis with either normal or impaired spermatogenesis. To our knowledge, this study is the first that has detected the mRNA of mucin9 and 13 in human testis. This study also shows that mucin1 expression might be closely related to spermatogenesis. Our findings should be substantiated by more direct evidence, such as mucin protein expression and localization.
Testis/*metabolism ; *Spermatogenesis ; Mucins/*genetics ; Middle Aged ; Male ; Humans ; Glycoproteins/genetics ; Antigens, Neoplasm ; Antigens/genetics ; Adult

Biomedical Research ; trends ; Breast Neoplasms ; metabolism ; Female ; Humans ; Mucins ; physiology ; Neoplasm Proteins ; physiology

Adenocarcinoma, Papillary ; diagnosis ; metabolism ; Carcinoma, Pancreatic Ductal ; diagnosis ; metabolism ; Cystadenoma, Mucinous ; diagnosis ; metabolism ; Gene Expression Regulation, Neoplastic ; Humans ; Mucins ; classification ; genetics ; metabolism ; Pancreas ; metabolism ; Pancreatic Neoplasms ; diagnosis ; metabolism

OBJECTIVETo investigate the expression of hypoxia inducible factor-1α (HIF-1α) in chronic rhinosinusitis (CRS) and relationship with mucin MUC5AC, MUC5B secretion.

METHODSThe expression of HIF-1α, MUC5AC and MUC5B were measured by immunohistochemistry (IHC), Western Blot and reverse transcription polymerase chain reaction (RT-PCR) in CRS with or without nasal polyps (CRSwNP: twenty-three or CRSsNP:twenty) and fifteen normal sinus mucosa without CRS. The relationship between HIF-1α and MUC5AC,MUC5B were analyzed by SPSS 16.0 software.

RESULTSPAS and IHC showed that HIF-1α, MUC5AC, MUC5B, total mucins were expressed in nuclear of epithelium and gland cells, which were higher than normal control (t values in epithelium cells were 8.650, 9.305, 9.382, 8.524, 7.533, 5.417, 5.507, 5.556, all P < 0.05; t values in gland cells were 8.285, 7.098, 6.798, 7.308, 8.574, 7.933, 6.798, 7.308, all P < 0.05), but there was no significant difference between CRSwNP and CRSsNP (t values in epithelium cells were 0.734, 0.415, 0.572, 0.248, all P > 0.05; t values in gland cells were 0.331, 0.662, 0.249, 0.644, P > 0.05).Western Blot revealed that HIF-1α protein in CRSwNP and CRSsNP were higher than in normal contral (t values were 3.522, 3.314, respectively, P < 0.05). The relative expression levels of HIF-1α, MUC5AC,MUC5B mRNA in CRSwNP and CRSsNP were 1.35 ± 0.84, 1.36 ± 0.94, 0.81 ± 0.54,0.78 ± 0.46, 1.13 ± 1.00, 1.22 ± 1.02. But the relative expression levels of HIF-1α, MUC5AC,MUC5B mRNA in control subjects were 0.43 ± 0.34, 0.42 ± 0.36, 0.48 ± 0.42. There were significant differences between the groups of CRSwNP and control subiects (t values were 4.087, 4.089, 2.519, 2.550, 2.738, 2.955, respectively, all P < 0.05). There was a positive correlation among the expression of HIF-1α and MUC5AC, 5B mRNA in CRSwNP (r values were 0.474,0.464, respectively, all P < 0.05). There was a positive correlation among the expression of HIF-1α and MUC5AC, 5B mRNA in CRSsNP (r values were 0.477,0.514, respectively, all P < 0.05).

CONCLUSIONSHIF-1α, MUC5AC and MUC5B expression were upregulated in CRS with or without nasal polyps, indicating CRS is a disease of mucus hypersecretion and there is a close association between HIF-1α with hypersecretion of MUC5AC and MUC5B in mucus.

Chronic Disease ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit ; metabolism ; Immunohistochemistry ; Mucins ; secretion ; Mucus ; Nasal Polyps ; RNA, Messenger ; Sinusitis ; metabolism

The temperature-sensitive hemagglutinin (Tsh) expressed by strains of avian pathogenic Escherichia (E.) coli (APEC) has both agglutinin and protease activities. Tsh is synthesized as a 140 kDa precursor protein, whose processing results in a 106 kDa passenger domain (Tsh(s)) and a 33 kDa beta-domain (Tsh(beta)). In this study, both recombinant Tsh (rTsh) and supernatants from APEC, which contain Tsh(s) (106 kDa), caused proteolysis of chicken tracheal mucin. Both rTsh (140 kDa) and pellets from wild-type APEC, which contain Tsh(beta) (33 kDa), agglutinated chicken erythrocytes. On Western blots, the anti-rTsh antibody recognized the rTsh and 106 kDa proteins in recombinant E. coli BL21/pET 101-Tsh and in the supernatants from APEC grown at either 37degrees C or 42degrees C. Anti-rTsh also recognized a 33 kDa protein in the pellets from APEC13 cultures grown in either Luria-Bertani agar, colonization factor antigen agar, or mucin agar at either 26degrees C, 37degrees C, or 42degrees C, and in the extracts of outer membrane proteins of APEC. The 106 kDa protein was more evident when the bacteria were grown at 37degrees C in mucin agar, and it was not detected when the bacteria were grown at 26degrees C in any of the culture media used in this study. Chicken anti-Tsh serum inhibited hemagglutinating and mucinolytic activities of strain APEC13 and recombinant E. coli BL21/pET101-Tsh. This work suggests that the mucinolytic activity of Tsh might be important for the colonization of the avian tracheal mucous environment by APEC.
Adhesins, Escherichia coli/*metabolism ; Brazil ; Escherichia coli/*metabolism ; *Gene Expression Regulation, Bacterial ; Hemagglutination ; Mucins/metabolism ; Protein Transport ; Recombinant Proteins/isolation & purification/metabolism

OBJECTIVETo explore the roles of epidermal growth factor receptor (EGFR) signaling pathway on cultured human nasal epithelial cells RPMI-2650.

METHODSRPMI-2650 cells were cultured in vitro, the growth curve was measured and the ultrastructure was observed using scanning electron microscope. When the cells were significantly confluent, they were divided into 4 groups, group A: maintained in Eagle's minimum essential media (EMEM) medium without adding any stimulators; group B: added with epidermal growth factor (EGF) 25 ng/ml; group C: added with AG1478 (EGFR selective inhibitor) 10 micromol/L followed by EGF 25 ng/ml 30 minutes later; group D: added with PD98069 (p44/42MAPK selective inhibitor) 30 micromol/L followed by EGF 25 ng/ml 30 minutes later. After incubated for 24 hours, the expression of EGFR and MUC5AC proteins in the cells of these 4 groups was studied using cytoimmunity and Western blotting.

RESULTSRPMI-2650 cells were significantly confluent after incubated for 5 to 7 days. The shape of cells was round or oval, and a large number of microvilli covered to their surface but without cilia under scanning electron microscope. The EGFR protein was expressed in the cells of group A and D, abundantly in group B, while weakly in group C. The values of comparative absorbance had significant difference between group A, B, D and group C, respectively (P < 0.01). For the MUC5AC protein, its expression was strong in the cells of group A, abundant in group B, and weak in group C and D. Significant difference of the values of comparative absorbance was analyzed between group B and group C, D, respectively (P < 0.01), while no difference between group C and group D (P > 0.05).

CONCLUSIONSThe production of MUC5AC in human nasal epithelial cells RPMI-2650 is regulated via the expression and activation of epidermal growth factor receptor signaling pathway.

Cell Proliferation ; Epithelial Cells ; metabolism ; Humans ; Mucin 5AC ; genetics ; metabolism ; Mucins ; metabolism ; Nasal Cavity ; cytology ; Receptor, Epidermal Growth Factor ; metabolism ; Signal Transduction ; Tumor Cells, Cultured