Establishment of an X-ray irradiation-induced glossitis model in rats: biphasic elevation of proinflammatory cytokines and chemokines.

Oral mucositis is a frequent and serious side effect in patients who receive radiotherapy for head and neck cancer. The purpose of this study was to develop a noninvasive and quantitative model of oral mucositis in rats, investigate the pathophysiology, and evaluate the efficacy of pharmacological interventions. Rats received a single dose of 15 Gy of X-rays to the snout after shielding of the remainder of the rat body with lead plates to protect the body from irradiation (day 0). After irradiation, the macroscopic area of tongue injury gradually increased. The total area of injury and the ulcer-like area reached a maximum on day 7 and then gradually decreased until disappearance on day 28. Expression of proinflammatory cytokines and chemokines occurred transiently within 1-4 hours after irradiation and returned to a normal level at 24 hours. This expression was again observed from days 3 to 5 and increased significantly on day 7, which approximately coincided with the histologic severity of tissue damage. Subcutaneous administration of palifermin at 3 mg/kg per day for 3 consecutive days before irradiation completely prevented ulcer formation in this model. In conclusion, we established a novel model of glossitis in rats, induced by X-ray irradiation, in which biphasic elevations of expression of proinflammatory cytokines and chemokines could be monitored. This model is considered useful to investigate the pathophysiology of oral mucositis and evaluate the preventive effect of pharmacological interventions on oral mucositis induced by X-ray irradiation.

Up-regulation of vascular endothelial growth factor expression by adenosine through adenosine A2 receptors in the rat tongue treated with endotoxin.

The main focus of the present investigation is to evaluate a differential effect of adenosine on the up-regulation of vascular endothelial growth factor (VEGF) expression through adenosine A(2) receptors in the rat tongue treated with endotoxin (lipopolysaccharide: LPS). Angiogenesis in the rat tongue treated with LPS/incomplete Freund's adjuvant (IFA) or endotoxin/IFA/adenosine A(2) receptor (A(2)R) antagonists was examined using immunohistochemistry for LYVE-1, ED1, ED2, OX6, langerin and VEGF, and real-time polymerase chain reaction (PCR) for VEGF. The distributional density of both blood vessels and OX6(+) cells was significantly increased at day 8 after injection of LPS/IFA. The immunoreactive products of VEGF were intensely labelled in the cytoplasm of various antigen presenting cells (APCs) including dendritic cells (DCs) with double-immunofluorescence technique. Increase in VEGF mRNA expression level, the occupancy ratio of blood vessels, and the number of ED1(+), ED2(+), OX6(+), and langerin(+) cells was inhibited in the injured tongue of rats as a consequence of the treatment with A(2)R antagonists. The present results indicate that the LPS-induced adenosine might promote angiogenesis by the up-regulation of VEGF expression in macrophages/DCs through A(2) receptors. This suggests that the synergistic interaction between toll-like receptor (TLR) and A(2) receptor signalling observed in vivo plays an important role in oral mucosal wound healing.

High JC virus load in tongue carcinomas may be a risk factor for tongue tumorigenesis.

The John Cunningham virus (JCV) asymptomatically infects a large proportion (approximately 90%) of the population worldwide but may be activated in immunodeficient patients, resulting in progressive multifocal leukoencephalopathy. Recent reports demonstrated its oncogenic role in malignancies. In this paper, the presence of JCV-targeting T antigen was investigated in tongue carcinoma (TC, n = 39), dysplastic tongue epithelium (DTE, n = 15) and glossitis (n = 15) using real-time polymerase chain reaction (PCR) and in situ PCR and immunohistochemistry, and JCV copies were analyzed with the clinicopathological parameters of TCs. The results demonstrated that glossitis and DTEs had significantly lower copies of JCV (410.5 +/- 44.3 and 658.3 +/- 53.3 copies/mug DNA respectively) than TCs (981.5 +/- 14.0, p < 0.05). When they were divided into three groups with 0-200 copies/mug DNA (low), 201-1,000 (moderate) and more than 1001 (high), TCs showed 3 (7.6%) in the low group, 21 (53.8%) in the moderate group and 15 (38.4%) in the high group and glossitis showed 11 (73.3%) in the low group, 0 (0%) in the moderate group and 4 (26.6%) in the high group. The DTEs occupied an intermediate position between them (p < 0.001). In situ PCR demonstrated that the nuclei of TC and DTE cells are sporadically T-antigen positive but not in nasal turbinate epithelial cells. Immunohistochemistry for T-antigen protein revealed four positive cases only in TCs. The existence of JCV T-antigen DNA was not associated with the clinicopathological variables of TCs. In conclusion, the presence of JCV may be a risk factor of tongue carcinogenesis.

Immunohistochemical and ultrastructural identification of Fusobacterium necrophorum subsp. necrophorum in bovine fatal necrotizing glossitis.

A 37-day-old male Japanese black calf showing marked salivation and leucocytosis died and was examined the tissues histologically. Histological lesions were characterized by severe focal necrotic glossitis on the ventral side of the root of the tongue. Immunohistochemically, Fusobacterium necrophorum subsp. necrophorum antigen was detected in the necrotic tissues and its distribution corresponded to that of the gram-negative, nonsporeforming, long filamentous organisms. Ultrastructural similarities between the organism and F. necrophorum subsp. necrophorum, but not subsp. funduliforme were observed. These findings clearly demonstrated that the fatal necrotic glossitis was caused by F. necrophorum subsp. necrophorum. This is the first report of bovine fatal necrotizing glossitis with leucocytosis caused by F. necrophorum subsp. necrophorum infection, and this organism may be an important fatal pathogen in calves with glossal lesions.

Defensin-1, an antimicrobial peptide present in the saliva of patients with oral diseases.

OBJECTIVES AND DESIGN: A preceding paper has noted a detection of defensin-1 (HNP-1), a peptide with antimicrobial and cytotoxic properties, in the saliva of patients with oral squamous cell carcinoma. The present study deals with the presence of HNP-1 in the saliva of patients with various oral diseases. METHODS: Whole saliva samples were obtained from the patients. HNP-1 in the saliva was isolated and purified by HPLC and the amino acid sequence of the peptide was determined. The molecular weight of HNP-1 was measured by mass spectrometry. The concentration of HNP-1 in saliva was determined by comparing the height of eluted HNP-1 with that of a synthetic HNP-1 standard. RESULTS: The concentrations of HNP-1 in the saliva of patients with oral lichen planus (n = 5), leukoplakia (n = 4), and glossitis associated with iron deficiency (n = 4) were 8.3 +/- 4.3 micrograms ml-1, 13.2 +/- 7.9 micrograms ml-1, and 11.4 +/- 4.9 micrograms ml-1, (mean +/- s.d.), respectively. These concentrations were significantly higher than those in healthy subjects (0.8 microgram ml-1) (P < 0.01). In contrast, salivary HNP-1 concentrations in patients with glossodynia (n = 4) and oral discomfort (n = 4) were similar to those in healthy subjects. CONCLUSIONS: Since HNP-1 is a non-specific defensive peptide present in neutrophils, it may play an important role in the protection against diseases such as oral lichen planus, leukoplakia, and glossitis associated with iron deficiency.

Epithelial antibiotics induced at sites of inflammation.

The role of antimicrobial peptides in epithelial defense is not fully understood. An epithelial beta-defensin, lingual antimicrobial peptide (LAP), was isolated from bovine tongue and the corresponding complementary DNA cloned. LAP showed a broad spectrum of antibacterial and antifungal activities. LAP messenger RNA abundance was markedly increased in the epithelium surrounding naturally occurring tongue lesions. This increase coincided with the cellular hallmarks of acute and chronic inflammation in the underlying lamina propria, supporting a role for epithelial antimicrobial peptides as integral components of the inflammatory response.

Median rhomboid glossitis associated with amyloid deposition.

There are some controversies over the pathogenesis and clinical features of median rhomboid glossitis. A case of median rhomboid glossitis associated with amyloid deposition was presented. Clinically there was no organ involved in amyloid other than the tongue. It was suspected that median rhomboid glossitis occurred first and that amyloid was induced later.