An involvement of granulocyte medullasin in phenytoin-induced gingival overgrowth in rats

Proteomic profiling differences in serum from silicosis and chronic bronchitis patients: a comparative analysis

BACKGROUND

Silicosis is a severe occupational disease characterized by pulmonary fibrosis, whereas chronic bronchitis (CB) is an acute inflammation of the airways. Differences in the mechanisms of pathogenesis of these diseases are not well understood, therefore we performed proteomic profiling of silicosis and CB patients and, compared the results.

METHODS

Two-dimensional gel electrophoresis and MALDI-TOF-MS (matrix assisted laser desorption ionization time of flight mass spectrometry) were used to identify differentially accumulated proteins in stage I of silicosis (SI), stage II of silicosis (SII) and CB. Enzyme linked immunosorbent assay (ELISA) was employed to validate protein expression data.

RESULTS

A total of 28 and 10 proteins were up- and down-regulated in SI, and 21 and 9 proteins were up- and down-regulated SII, compared with CB. Transforming growth factor beta-1 precursor and interferon beta precursor were up-regulated in CB, while interleukin 6, tumor necrosis factor (TNF) and a variant TNF receptor 13B were down-regulated in CB. Additionally, glycoprotein- and apolipoprotein-associated proteins including apolipoprotein A-IV and α-1-B-glycoprotein were up-regulated in CB, indicating an involvement in the pathogenesis of CB but not silicosis. By contrast, HLA-DRB1, medullasin and the proto-oncogene c-Fos were up-regulated in CB.

CONCLUSIONS

The immune, metabolism and apolipoprotein-related proteins were identified as playing specific and different roles in silicosis and CB. These proteomic profiling differences would facilitate further studies on the mechanisms underlying silicosis and CB, and may also prove useful to disease diagnosis and treatments.

Exogenous factors in the immunotoxicity of oral PMN

Current evidence indicates that periodontal disease is frequently due to inappropriate levels of gingival granulocyte functions. Reason of this failure may be the toxic effects of a number of local or systemic exogenous factors, capable of spreading through the gingival crevice environment, and strongly conditioning the granulocyte activities. The wide list includes bacteria and granulotoxic products, hedonistic drugs (mainly tobacco), and chemotherapeutic agents (especially antimicrobials used for preventing or reducing the accumulation of dental plaque). Almost always, their presence induces a time- and/or dose-dependent toxicity.

Establishment of rat model of drug-induced gingival overgrowth induced by continuous administration of phenytoin

It is well-known that the anticonvulsant drug, phenytoin (PHT), induces gingival overgrowth as a side effect. The mechanism of PHT-induced gingival overgrowth, however, is not well understood. One reason for this is the lack of an adequate animal model for the PHT-induced gingival overgrowth. The purpose of this study was to establish a rat model of the drug-induced gingival overgrowth. Fourteen-day-old rats were randomly divided into 3 groups (5 rats/group). The control rats received only the vehicle. The rats in the experimental group were injected with 50 mg/kg per day (group L) and 100 mg/kg per day (group H) of PHT. They received a subcutaneous injection of vehicle or PHT twice a day for 42 days. A charge-coupled device (CCD) laser displacement sensor was used for measurement of the severity of gingival overgrowth of the mandibles. There was no significant difference in the growth of rats between the PHT-injected and the control groups. The CCD laser displacement sensor can measure minute changes in the gingival overgrowth in rats, and a significant extension of the buccal gingiva was observed in groups L and H. Using the CCD sensor, it is possible to quantify the change in the gingiva under precise control of the PHT dose.