Gülnihal Eren

Effect of centrifugation time on growth factor and MMP release of an experimental platelet-rich fibrin-type product

Abstract Platelet-rich fibrin (PRF) has a controlled release of growth factors due to the fibrin matrix structure. Different centrifugation protocols were suggested for PRF preparation. Since the derivation method of PRF can alter its contents, in the present study it is aimed to investigate the cell contents and transforming growth factor beta-1 (TGF-β1), platelet-derived growth factor (PDGF-AB), vascular endothelial growth factor (VEGF), matrix metalloproteinase (MMP)-1 and-8 release from experimental PRF-type membranes obtained with different centrifugation times at 400 gravity. Three blood samples were collected from 20 healthy non-smoker volunteers. One tube was used for whole blood analyses. The other two tubes were centrifuged at 400 g for 10 minutes (group A) or 12 minutes (group B). Each experimental PRF-type membrane was placed in Dulbecco’s Modified Eagle’s Medium (DMEM)and at 1, 24 and 72 hours, TGF-β1, PDGF-AB, VEGF, MMP-1 and -8 release amounts were analysed by enzyme-linked immunosorbent assay (ELISA). The blood cell count of membranes was determined by subtracting plasma supernatant and red blood cell (RBC) mixture from the whole blood cell counts. At 72 hours, the VEGF level of group B was statistically higher than that of group A (p = 0.040). The centrifugation time was not found to influence the release of other growth factors, enzymes and cell counts. Within the limits of the present study, it might be suggested that centrifugation time at a constant gravity has a significant effect on the VEGF levels released from experimental PRF-type membrane. It can be concluded that due to the importance of VEGF in the tissue healing process, membranes obtained at 12-minute centrifugation time may show a superior potential in wound healing.

Does smoking affect gingival crevicular fluid LL-37 levels following non-surgical periodontal treatment in chronic periodontitis?

OBJECTIVE LL-37 contributes to maintaining the balance between health and disease. Smoking is a risk factor for periodontitis that impairs neutrophil functions. The aim of the present study was to comparatively evaluate gingival crevicular fluid (GCF) LL-37 levels in smoker and non-smoker chronic periodontitis (CP) patients and controls, as well as the effect of non-surgical periodontal treatment on GCF LL-37 levels. DESIGN Thirty-one CP patients (16 smokers, 15 non-smokers) and thirty-one controls (16 smokers, 15 non-smokers) were included in the study. CP patients received non-surgical treatment. GCF LL-37 levels and periodontal parameters were assessed at baseline, 1 and 3 months after completion of non-surgical periodontal treatment. GCF LL-37 levels were analyzed by ELISA. RESULTS No significant difference was observed in GCF LL-37 levels between smoker and non-smoker controls (p>0.05). Smoker CP group had significantly lower GCF LL-37 level than non-smoker CP group at baseline (p<0.05). GCF LL-37 levels significantly decreased in non-smoker CP group at first week, 1 and 3 months after completion of non-surgical periodontal treatment (p<0.05) although no significant decrease in GCF LL-37 levels was observed in smoker CP group (p>0.05). Periodontal parameters were correlated with GCF LL-37 levels in non-smoker CP group (p<0.05), but not in smoker CP group (p>0.05). CONCLUSIONS GCF LL-37 levels do not seem to be affected from smoking in periodontal health. However, smoking might have a suppressive effect on GCF LL-37 levels in CP. Non-surgical treatment is effective in decreasing GCF LL-37 levels in non-smoker CP patients but not in smokers with CP.

EVALUATION OF THE RELATIONSHIP BETWEEN AGE AND ANTIMICROBIAL PEPTIDE LL-37 LEVELS IN GINGIVAL CREVICULAR FLUID

Purpose: LL-37 is an antimicrobial peptide which plays an important role in the innate immunity. The aim of this study was to investigate the LL-37 levels in the gingival crevicular fluid (GCF) of middle-aged and young adults who have either gingivitis or healthy periodontal tissues. Materials and Methods: Forty middle-aged adults (20 healthy controls and 20 with gingivitis) and 41 younger adults (20 healthy controls and 21 with gingivitis) were included in the present study. Probing depth, clinical attachment level, plaque index, and papilla bleeding index were recorded. LL-37 levels in the GCF were analyzed by enzyme-linked immunosorbent assay. Results: No significant differences were observed in the GCF LL-37 levels between young healthy and middle-aged healthy subjects. Also, there were no significant differences in GCF LL-37 levels between young and middle-aged gingivitis subjects. However, gingivitis groups had significantly higher GCF LL-37 levels than healthy groups (p<0.001). Correlation analysis demonstrated no significant correlation between age and GCF LL-37 levels neither in healthy nor in gingivitis groups. Conclusion: The levels of LL-37 in GCF increase in the presence of gingival inflammation, however, this does not vary according to subjects being young or middle-aged.

Monocyte chemotactic protein-1, RANTES and macrophage migration inhibitory factor levels in gingival crevicular fluid of metabolic syndrome patients with gingivitis.

OBJECTIVE The aim of the present study was to determine gingival crevicular fluid (GCF) levels of monocyte chemotactic protein-1 (MCP-1), regulated on activation, normal T-cell expressed and secreted protein (RANTES) and macrophage migration inhibitory factor (MIF) in metabolic syndrome patients with gingivitis. DESIGN Twenty metabolic syndrome patients with gingivitis (MSG), 20 MetS patients with clinically healthy periodontium (MSH), 20 systemically healthy subjects with gingivitis and 20 subjects who were both systemically and periodontally healthy were included. Periodontal and systemical parameters were recorded. GCF MCP-1, RANTES and MIF levels were assayed by enzyme-linked immunosorbent assay method. RESULTS MSG and MSH groups had elevated blood pressure, triglyceride, waist circumference and fasting glucose values in comparison to gingivitis and healthy groups (P<0.0001). Clinical periodontal parameters were higher in MSG and gingivitis groups when compared to those of the MSH and healthy groups (P<0.0001). MCP-1 and RANTES levels (ng/mg total protein) of MSG group were higher than those of the MSH groups (P=0.005, P=0.0001, respectively). Also gingivitis group had higher MCP-1, RANTES and MIF levels compared to the healthy group (P=0.011, P=0.0001, P=0.011 respectively). The RANTES level of MSG group was significantly higher than those of the gingivitis group (P=0.01), but MCP-1 and MIF levels were similar in the MSG and gingivitis groups (P>0.05). CONCLUSION Elevated levels of GCF RANTES in MetS patients with gingivitis might associate with the presence of increased gingival inflammation by MetS. Low-grade systemic inflammation associated with MetS and adipose tissue-derived RANTES might lead to altered GCF RANTES levels in the presence of gingival inflammation.

Evaluation of gingival crevicular fluid cyclophilin a and extracellular matrix metalloproteinase inducer levels in different periodontal diseases

OBJECTIVE Cyclophilin A (CypA) is able to regulate inflammatory responses and matrix metalloproteinase production via its interaction with extracellular matrix metalloproteinase inducer (EMMPRIN). EMMPRIN is the cell surface receptor of CypA. The aim of the present study was to evaluate the gingival crevicular fluid (GCF) CypA and EMMPRIN levels in patients with chronic periodontitis (CP), generalized aggressive periodontitis (G-AgP) and periodontally healthy controls. METHODS Twenty CP patients, 19 G-AgP patients and 20 healthy control subjects were included in the present study. All study participants were non-smokers. Full mouth clinical periodontal parameters including probing depth, clinical attachment level, plaque index, and papilla bleeding index were recorded. GCF CypA and EMMPRIN levels were analyzed by enzyme-linked immunosorbent assay. Data were analyzed statistically with parametric and non-parametric tests. RESULTS GCF CypA total amount was higher in the G-AgP group compared to healthy controls (p<0.05), whereas CypA total amounts were similar in CP and healthy controls (p>0.05). No significant difference in GCF CypA total amount between CP and G-AgP was observed (p>0.05). Also, there was no significant difference in GCF EMMPRIN total amounts among the study groups (p>0.05). CONCLUSION Higher levels of GCF CypA in patients with G-AgP might demonstrate that CypA is associated with the inflammatory infiltrate and alveolar bone destruction of G-AgP. However, GCF CypA level does not seem to be affected by CP. Similar GCF EMMPRIN levels in diseased and healthy groups might suggest that EMMPRIN has role in the turn over of connective tissues in physiological conditions as well as pathological state.