Résumé
<p><b>OBJECTIVE</b>To investigate the effects of advanced oxidative protein products (AOPP) on the proliferation, apoptosis and matrix metalloproteinase-1 (MMP-1) synthesis of the human gingival fibroblast (HGF). To explore the possible mechanism of the periodontal destruction acceleration in diabetes through AOPP-mediated oxidative stress.</p><p><b>METHODS</b>HGF were isolated by both tissue explant cultivation technique and enzyme digestion method. The culture media with 5, 50, 100 mg/L AOPP-HAS were added into each experimental group, but the culture media in the control group didn't contain AOPP-HAS. MTT colorimetric assay and ELISA were used to measure the changes of HGF proliferation and the levels of MMP-1 protein from HGF at different time periods, respectively. Seventy-two hours after co-culture with 50 mg/L AOPP-HSA, cell apoptosis was detected by flow cytometry with Annexin V/PI staining.</p><p><b>RESULTS</b>Compared to the control group, the growth inhibition rate of HGF in 5, 50, 100 mg/L AOPP-HSA group was significantly different (P < 0.05). The peak value appeared at 48 hours of co-culture [(19.01 +/- 6.28)%, (30.48 +/- 5.75)%, (39.75 +/- 4.60)%, respectively]. There was a dose-dependent relationship between the growth inhibition rate and AOPP-HSA. No significant difference was detected on the apoptotic level between experimental group and the control (P > 0.05). The MMP-1 synthesis in 0.5, 5, 50, 100 mg/L AOPP-HAS group [(55.61 +/- 1.06), (65.78 +/- 4.04), (79.24 +/- 3.09), (89.76 +/- 28.88) mg/L, respectively] was significantly higher than that in the control [(34.90 +/- 3.15) mg/L] after 72 hours co-culture (P < 0.05). There was a dose-dependent relationship between MMP-1 and AOPP-HSA.</p><p><b>CONCLUSIONS</b>AOPP may inhibit the proliferation of HGF and such effect was not achieved through apoptosis. AOPP may increase collagen degradation by promoting MMP-1 synthesis and thus may accelerate periodontal destruction process in diabetes.</p>
Sujets)
Humains , Apoptose , Protéines du sang , Métabolisme , Prolifération cellulaire , Cellules cultivées , Gencive , Biologie cellulaire , Matrix metalloproteinase 1 , Métabolisme , Oxydoréduction , Stress oxydatifRésumé
<p><b>OBJECTIVE</b>To investigate the changes of proportion and suppression function of CD-4+ CD-25+ regulatory T cells in the peripheral blood of patients with aggressive periodontitis.</p><p><b>METHODS</b>Flow cytometric analysis was used to detect the frequency of CD-4+ CD-25+ regulatory T cells in the peripheral blood of 16 patients with generalized aggressive periodontitis and 17 patients with chronic periodontitis, as well as 17 periodontal healthy controls. Furthermore, CD-4+ CD-25+ regulatory T cells and CD-4+ CD-25- T cells were separated from peripheral blood of each enrolling subject using magnetic cell sorting technology. The direct suppression effect of CD-4+ CD-25+ regulatory T cells on CD-4+ CD-25- T lymphocytes proliferation was performed by the mixed lymphocytes reaction and measured by 3H-thymidine radioactive assay.</p><p><b>RESULTS</b>The patients with generalized aggressive periodontitis had a lower frequency of CD4+ CD-25+ regulatory T cells (9.71 +/- 4.01)% in the peripheral blood than periodontal healthy controls [(14.72 +/- 3.51)%] and chronic periodontitis patients [(17.01 +/- 5.16 )%], P < 0.05. A significant decrease was found in the suppression function of CD-4+ CD-25+ regulatory T cells from peripheral blood of patients with generalized aggressive periodontitis when co-cultured with CD-4+ CD-25- T lymphocytes in the proportion of 2 : 1, 1 : 1 and 1 : 2 as compared with chronic periodontitis patients and periodontal healthy controls (P < 0.05).</p><p><b>CONCLUSIONS</b>Diminished numbers and decreased suppression function of CD-4+ CD-25+ regulatory T cells were found in patients with generalized aggressive periodontitis.</p>