[TGF-beta 1 in the experimentally induced inflammatory periodontal tissues in miniature swines]

TGF-beta 1 is a multifunctional molecule which has unique and potent effects on many target cells and tissues. TGF-beta 1 may promote inflammatory reaction by certain intercellular interaction. TGF-beta 1 at extremely low concentrations shows strong chemotatic activity for mononuclear phagocytes and stimulates bone resorption by enhancing production of PGE2. On the other hand, TGF-beta 1 plays a very important role in the regulation of extracellular matrix turnover presumably by modulating the action of other growth factors on matrix metalloproteinases (MMPs) and tissue inhibitor of metalloproteinases (TIMPs) expression. TGF-beta 1 was identified intra- and extracellularly in the inflamed gingival tissues and the distribution was associated with areas of inflammation. Sixteen miniature swines were used in this experimental gingivitis/periodontitis study. The ligatures were placed in situ for periods of 3, 5, 8 and 13 weeks and peroral innoculations of Porphyromonas gingivalis/Actinomyces viscosus into the ligatures were carried out only in the experimental group. ELISA was used to measure the levels of TGF-beta 1 in gingival tissues from the experimental and control groups. Recording of the clinical periodontal parameters was performed and the proportion of black-pigmented Bacteroides in the ligature (plaques) removed immediately prior to the biopsies was recorded. The results revealed that the concentration of TGF-beta 1 of the experimental group was higher and significantly different in statistics on the period of third week than that of the control group. The concentration of TGF-beta 1 was significantly different between the third week and the thirteenth week in the experimental group, and was negatively related to the time-length of ligatures. Furthermore, the concentration of TGF-beta 1 was negatively related to the changes of the calculus index and gingival index. These data indicated that the concentration of TGF-beta 1 of gingival tissue exhibited dynamic changes associated with the progression of experimental periodontal inflammation. The levels of TGF-beta 1 in gingival tissue may be valuable in detecting the inflammatory reaction of periodontal tissues.