Effects of NSAIDs on beagle crevicular cyclooxygenase metabolites and periodontal bone loss

This investigation focuses on the changes in the concentrations of cyclooxygenase (CO) products present within the crevicular fluid in naturally-progressing periodontitis in the beagle and the effects of various non-steroidal anti-inflammatory drugs (NSAIDs) on these metabolite levels and disease progression. Six groups of 5-6 beagles with periodontitis were followed for 6 months to determine the pretreatment rate of radiographic bone loss. At baseline, groups of animals were placed on soft chow to promote disease progression. Groups were treated with either placebo, three different formulations of systemic ibuprofen, systemic naproxen or topical flurbiprofen. During the 6-month treatment phase, crevicular fluid (CF) samples and radiographs were taken at regular intervals. Radioimmunoassay of CF samples from untreated animals demonstrated a steady increase in prostaglandin E2 (PGE2) over baseline values. At 1 month, CF-PGE2 levels increased 2-fold over baseline and, by 6 months, had reached a 5- to 6-fold elevation. Crevicular fluid thromboxane B2 (CF-TxB2) levels rapidly reached a 4- to 5-fold peak over baseline at 1 month and subsequently dropped to a 2-fold elevation for the remainder of the study. The rate of bone loss (BLOSS) in untreated animals increased 38% during the 6-month period, as compared to baseline pretreatment BLOSS rates. Overall, there was a significant depression in the CF levels of both PGE2 and TxB2 in all NSAID-treated groups. All NSAID treatments significantly retarded BLOSS, ranging from 21.0-36.9% of the control BLOSS rate. Furthermore, CO activation represents a major regulatory step in bone destruction and may thereby serve as an important site for pharmacological modulation.     

The use of crevicular fluid prostaglandin E2 levels as a predictor of periodontal attachment loss

Longitudinal data were collected over a period of at least 18 months and up to 3 years on 41 adult periodontitis patients (AAP Type III and IV). Ramfjord attachment level measurements and sampling of crevicular fluid (CF) at each tooth were repeated every 3 months. A mean full mouth CF prostaglandin E₂ (MCF-PGE) value was determined for each patient at each visit. The three-month monitoring was continued until a single site demonstrated a statistically and clinically significant attachment loss (ALOSS) episode. Results indicated that in ALOSS patients the MCF-PGE was significantly elevated at the ALOSS visit as compared to previous levels. Furthermore, the sites which had the ALOSS had elevated levels as compared to the contralateral no ALOSS control sites (305.6±56.5 vs. 65.7±6.89 ng/ml, mean ± SEM). One month following treatment the CF-PGE level dropped to 16.9±3.4 ng/ml at the ALOSS sites. Since the MCF-PGE level increases preceding the attachment loss episode, reaches a maximum at the sites which actually undergo ALOSS, and subsides following treatment, the possibility of using the MCF-PGE level to predict an oncoming future ALOSS episode was examined. The ALOSS patients had a MCF-PGE level of 113.4±9.0 ng/ml 6 months prior to the ALOSS episode, which was significantly higher than the no ALOSS patients'MCF-PGE level of 50.1±7.1. Analysis of MCF-PGE levels as a screening test indicate that this measurement has a high degree of sensitivity, specificity, and a predictive value of 0.92–0.95. Thus, this method has significant merit as a diagnostic tool to determine if a patient is in a state of remission or about to undergo an attachment loss episode.     

Effects of flurbiprofen on the progression of periodontitis in Macaca mulatta

The effect of the nonsteroidal anti-inflammatory drug flurbiprofen has been studied in the ligature-induced and spontaneous periodontitis model in the rhesus monkey, Macaca mulatta. Twenty-four adult monkeys with incipient periodontitis were divided into three disease-matched groups. Two groups received flurbiprofen at dosages of either 0.27 mg/kg/d or 7.1 mg/kg/d delivered systemically via osmotic minipump. A split-mouth approach was used, placing ligatures on one side and monitoring the progression of periodontitis at regular intervals for 6 months. Clinical measurements included standardized radiographs, Ramfjord attachment level determinations and assessments of redness, edema and bleeding on probing. There was a statistically significant inhibition of attachment loss (p < 0.05), gingival redness (p < 0.05) and bleeding on probing (p < 0.05) in ligatureinduced and spontaneous periodontitis in the flurbiprofen-treated animals at 6 months. Eight of 8 ligated control monkeys lost significant attachment (mean loss of 1.06 mm/site). Only 3 of 15 flurbiprofen-treated ligated monkeys lost any significant attachment, with an overall mean loss of 0.34 mm/site, which was significantly less than the control loss of 1.06 mm/site at p = 4.46 times 10^-3. The odds of a control ligated monkey undergoing significant attachment loss in 6 months are elevated 29.3-fold, as compared to the flurbiprofen-treated, cohort monkey group. Flurbiprofen treatment also significantly inhibited spontaneous attachment loss for 6 months as compared to control monkeys, at p < 0.05. These data provide further evidence for the central role of cyclooxygenase products in the progression of periodontal disease. The ability of flurbiprofen to inhibit periodontal attachment loss, even in the presence of gross plaque accumulation, has significant implications for the potential use of flurbiprofen as an adjunctive periodontal therapeutic modality.     

Flurbiprofen in the prevention and treatment of experimental gingivitis

Abstract A clinical trial was undertaken to examine the effects of a potent cyclooxygenase inhibitor, flurbiprofen, on both developing and established gingivitis in humans. 21 subjects with healthy gingiva abstained from all oral hygiene procedures for 21 days. 7 subjects were prescribed flurbiprofen, 50 mg b.d. beginning from baseline and a control group (Cl. n= 14) were given placebo. Gingival redness and bleeding on probing were assessed at baseline, 7, 14 and 2J days. Crevicular fluid (GCF) samples were also taken to determine concentrations of PGE₂, TxD₂ and LTB₄ at baseline and at 21 days. Results show that flurbiprofen significantly inhibited the development of redness and bleeding (p < 0.001) effects which were associated with a significant inhibition of TxB₂ (p < 0.05). There were no apparent flurbiprofen effects on GCF-PGE₂ or GCF-LTB₄ during this 21-day gingivitis model. To assess the effects of flurbiprofen on established experimental gingivitis, the model was extended to 28 days. On day 21, the C1 group was subdivided into 2 groups of 7 subjects. One group was prescribed flurbiprofen (50 mg b.d.) for 7 days and controls (C2) continued to take placebo. All subjects continued to abstain from tooth cleaning. Pretreatment (day 21) and post-treatment (day 28) comparisons showed that flurbiprofen again significantly inhibited bleeding (p < 0.001), but did not affect redness. Control subjects demonstrated a significant elevation in gingival bleeding on day 28, and this was associated with significant rises in GCF-PGE₂ (p < 0.001), GCF-TxB₂ (p < 0.01) and GCF-LTB₄ (p < 0.05). Flurbiprofen suppressed the increases in these 3 mediators that occurred between 21 and 28 days. It is concluded that flurbiprofen controls gingival inflammation with both preventive and therapeutic properties in the experimental gingivitis model, an action that is associated with an inhibition in the production of both cyclooxygenase metabolites and indirectly affects GCF-LTB₄ levels.     

Indomethacin or flurbiprofen treatment of periodontitis in beagles: Effect on crevicular fluid arachidonic acid metabolites compared with effect on alveolar bone loss

The effect of two non-steroidal anti-inflammatory drugs, indomethacin and flurbiprofen, on the progression of alveolar bone loss and on the crevicular fluid (CF) levels of four arachidonic acid metabolites was compared in 16 beagle dogs over a 12-month period. Standardized radiographs were used to measure the rate of bone loss. Radioimmunoassay was used to measure CF levels of PGE₂, PGF_2α, TxB₂ and 6K-PGF_1α. Following a 6-month pretreatment baseline period, 5 dogs were dosed daily with 1.0 mg/kg indomethacin, 5 dogs were dosed daily with 0.02 mg/kg flurbiprofen, and 6 dogs were dosed with empty gelatin capsules for a 6-month period. With the administration of either indomethacin or flurbiprofen. the CF levels of PGE₂, PGF_2α, and TxB₂ were similarly significantly decreased; 6K-PGF_1α levels were not altered. Indomethacin and flurbiprofen did not have a similar effect on reducing the rate of alveolar bone loss. Flurbiprofen significantly decreased rate of bone loss from baseline whereas indomethacin did not. The data indicate that indomethacin and flurbiprofen inhibit CF arachidonic acid metabolite levels in a similar manner, but not rate of bone loss. The data suggest that flurbiprofen's striking effect on inhibiting rate of bone loss cannot be solely attributed to simple cyclooxygenase inhibition with a reduction in CF prostaglandin levels.     

Flurbiprofen treatment of human periodontitis: effect on alveolar bone height and metabolism

The effect of the non-steroidal anti-inflammatory drug, flurbiprofen, in reducing periodontal disease activity was assessed in 15 patients with periodontitis. Eight patients received 50 mg flurbiprofen b.i.d. for 2 months, and 7 patients received placebo in this double-blind study. Alveolar bone height was determined using standardized radiography and alveolar bone metabolism was assessed using 99m-Tc-uptake prior to dosing and 2 months later. Radiopharmaceutical uptake was significantly reduced in the alveolar bone of teeth undergoing active bone loss at the start of the study in patients receiving flurbiprofen (p<.04), whereas no significant change was observed in the placebo-treated patients. There was significantly less bone loss during the 2-month study period in the flurbiprofen-treated patients when compared to the placebo-treated patients (p< .02). These results indicate that flurbiprofen administration may affect bone metabolism and reduce bone loss in patients with periodontitis.     

前列腺素E2和血栓素B2在根尖周炎中的定量研究

目的：分析前列腺素E2（prostaglandin E2,PGE2)和血栓素A2（thromboxane A2,TXA2）与根尖周炎临床表现的关系，探讨两者在根尖周炎发生、发展中的作用。方法：采用放射免疫技术对69位患者135例不同状态尖周渗出液中PGE2与TXB2（TXA2物稳定代谢产物）进行质量浓度测定，并计算两者比值，同时测量渗出液体积，应用Wilcoxon秩和检验进行统计分析。结果：PGE2质量浓度在治疗前有症状组明显高于无症状组（P＜0.01），治疗期间急 发作其质量浓度升至最高，经根管治疗后降至最低。TXB2的测量结果恰相反、尖周渗出液体积在治疗前有症状组显著多于无症状组，治疗后明显减少。结论：PGE2与TXA2积极参与并影响着根尖周炎的发生、发展与转归。     

Longitudinal evaluation of prostaglandin E2 (PGE2) and periodontal status in HIV+ patients

The study aim was to determine whether prostaglandin E(2) (PGE(2)) in gingival crevicular fluid (GCF) could serve as a risk factor for periodontitis in human immunodeficiency virus-positive (HIV(+)) patients. Clinical measurements, including gingival index (GI), plaque index, bleeding index, probing depth (PD), attachment loss (AL) and GCF samples were taken from two healthy sites (including sites with gingival recession, GI=0; PD< or =3 mm; AL< or =2 mm), three gingivitis sites (GI>0; PD< or =3 mm; AL=0) and three periodontitis sites (GI>0; PD> or =5 mm; AL> or =3 mm) of each of the 30 patients at baseline and 6-month visits. GCF samples were also taken by means of paper strips. GCF PGE(2) levels were determined by a sandwich ELISA. The progressing site was defined as a site which had 2 mm or more attachment loss during the 6-month study period. The mean amounts of PGE(2) were significantly higher in gingivitis and periodontitis sites than in healthy sites (p<0.0001). GCF levels of PGE(2) were significantly correlated with probing depth, attachment loss, CD4(+) cells, viral load, age and smoking pack-years at baseline and 6-month visits (0.0001相似文献   

Effect of a controlled-release chlorhexidine chip on clinical and microbiological parameters and prostaglandin E2 levels in gingival crevicular fluid

BACKGROUND: The aim of the present study was to determine the effect of a chlorhexidine chip on crevicular prostaglandin E2 (PGE2) levels and on the clinical and microbiological parameters of periodontitis when used as adjunctive therapy to scaling and root planing (SRP) in patients with chronic periodontitis. METHODS: This randomized single-blind study was carried out in parallel design. The test group received SRP plus chlorhexidine chip, whereas the control group received SRP alone. Thirty-four subjects, aged 20 to 55 years, with chronic periodontitis were recruited. Clinical indices, microbiological samples, and gingival crevicular fluid (GCF) samples were evaluated at baseline and after 1, 3, and 6 months. Microbiological samples were evaluated under a light microscope. GCF PGE2 levels were determined using radioimmunoassay. RESULTS: Significant improvements could be found for all clinical variables in both groups over the study period. The mean changes in probing depth obtained by SRP plus chlorhexidine chip were greater than those obtained by the SRP alone group at 3 and 6 months. In the test group, there was also significant gain in clinical attachment level at 6 months. When data were combined from all groups, significant reductions in GCF PGE2 levels and number of microorganisms were noted at all time points. However, in the test group, reduction was greater at 6 months for crevicular PGE2 level and at 3 and 6 months for proportions of spirochetes. CONCLUSION: Based on the findings of this study, the chlorhexidine chip reduced GCF PGE2 levels and had positive effects on clinical parameters and subgingival flora when used as adjunctive therapy to SRP in patients with chronic periodontitis.     

Dexamethasone suppresses peripheral prostanoid levels without analgesia in a clinical model of acute inflammation.

PURPOSE: The therapeutic effects of glucocorticoids are generally attributed to suppression of multiple signaling pathways involved in the inflammatory response leading to decreased levels of inflammatory mediators at the site of injury. This study evaluated the in vivo relationship between levels of prostanoids at the site of tissue injury and analgesia after dexamethasone administration in a clinical model of tissue injury. METHODS: Subjects were administered dexamethasone 4 mg or placebo 12 hours and 1 hour before the removal of 2 mandibular third molars. A microdialysis probe was implanted at each surgical site for measurement of immunoreactive prostaglandin E2 (PGE(2)) or immunoreactive thromboxane B(2) (TxB(2)), and pain was measured concurrently. Subjects received either ketorolac 30 mg intravenously or placebo at pain onset. RESULTS: PGE(2) was detectable in the first postoperative sample, decreased over the next hour and then increased coincident with the onset of postoperative pain. Administration of dexamethasone suppressed PGE(2) levels in samples collected at pain onset in comparison to placebo and significantly suppressed TxB(2) at the surgical site but without any effect on pain report. Subsequent administration of ketorolac significantly reduced pain while decreasing both PGE(2) and TxB(2) levels at the surgical site. CONCLUSION: The lack of an analgesic effect for dexamethasone while reducing both PGE(2) and TxB(2) at the site of injury in comparison to ketorolac analgesia accompanied by greater reductions in levels of these prostanoids suggests that glucocorticoids at this dose do not suppress PGE(2) release sufficiently to attenuate peripheral sensitization of nociceptors after tissue injury.     

Altering the progression of human alveolar bone loss with the non-steroidal anti-inflammatory drug flurbiprofen

The treatment of human periodontal diseases relies on mechanical and antimicrobial suppression of the etiologic bacteria. The ability to alter the progression of periodontitis by additionally blocking host pathways involved in the destructive process is an area of current research. Prostaglandins and other metabolites of arachidonic acid are believed to be important host mediators of the bone resorption of diseases such as periodontitis. We have previously examined the effect of inhibitors of prostaglandin production, non-steroidal anti-inflammatory drugs (NSAIDs), on inhibiting alveolar bone loss in beagles. The present study was designed to examine the effect of the NSAID, flurbiprofen, on slowing the radiographic loss of alveolar bone in the human. Fifty-six individuals with radiographic evidence of alveolar bone loss were recruited for study. Forty-four patients remained in the study for the data analysis of loss of alveolar bone. Following a 6 month baseline pretreatment period to measure the radiographic progression of bone loss, half of the patients were administered flurbiprofen, 50 mg. b.i.d., while half were administered a placebo. All patients received a subgingival scaling and pumice by a hygienist every 6 months. The rate of alveolar bone loss in a 2 year treatment period was compared to the baseline 6 month pretreatment period within and between patient groups. Throughout the study, teeth exhibiting obvious loss of bone were exited from study and treated with conventional mechanical therapy. At the end of the pretreatment period both patient groups had a similar mean rate of alveolar bone loss.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gingival crevicular fluid prostaglandin E(2) and thiobarbituric acid reactive substance levels in smokers and non-smokers with chronic periodontitis following phase I periodontal therapy and adjunctive use of flurbiprofen

BACKGROUND: It has been established that smoking is an important risk factor for the initiation and progression of chronic periodontitis (CP). This study investigates the effects of phase I periodontal therapy and adjunctive flurbiprofen administration on prostaglandin E(2) (PGE(2)) and thiobarbituric acid reactive substance (TBARS) levels in gingival crevicular fluid (GCF) samples from smoker and non-smoker patients with CP. METHODS: Twenty-one non-smoker and 21 smoker patients with CP were divided into four groups according to treatment modalities. Group 1 (non-smokers with CP) and group 3 (smokers with CP) patients received daily 100-mg flurbiprofen tablets in a 2 x 1 regimen for 10 days together with scaling and root planing (SRP). Patients in group 2 (non-smokers with CP) and group 4 (smokers with CP) received placebo tablets in a 2 x 1 regimen for 10 days together with SRP. Plaque index (PI), gingival index (GI), probing depth (PD), and clinical attachment level (CAL) measurements were recorded and GCF samples were collected at baseline and on day 10 of drug intake from each sampling area by a single examiner who was unaware of the treatment modality. Assays for GCF PGE(2) and TBARS were carried out by an enzyme-linked immunosorbent assay and fluorometric method, respectively. RESULTS: All groups showed statistically significant reductions in PI and GI scores following the phase I periodontal treatment on day 10 (P <0.05), but no statistical differences were observed in PD and CAL scores after the therapy. In groups 1 and 2, the reduction of GCF PGE(2) and TBARS levels were not significant after the therapy compared to baseline levels. In group 3, GCF PGE(2) and TBARS levels exhibited a statistically significant decrease (P <0.05) after the therapy. Group 4 showed significant reductions (P <0.05) in GCF PGE(2) levels after the therapy. No statistically significant reductions were observed in group 4 with regard to GCF TBARS levels. When groups 1 and 3 were compared according to GCF TBARS levels after the therapy, a more statistically significant reduction was observed in group 3 (P = 0.001). CONCLUSION: These results suggest that additional flurbiprofen administration may have more inhibitory effects on GCF levels of PGE(2) and TBARS in the groups of smokers compared to non-smokers with CP.     

Combined effects of caffeine and prostaglandin E2 on the proliferation of osteoblast-like cells (UMR106-01)

BACKGROUND: The general public widely consumes caffeine (1,3,7-trimethylxanthine), which is contained in various foods, beverages and over-the-counter medications. We have shown previously that caffeine intake could affect bone metabolism in vivo. METHODS: Because prostaglandin E2 (PGE2) is shown to be elevated in the periodontally diseased site, the possible interaction between caffeine and PGE2 was investigated in the present study using UMR106-01 rat osteoblast-like cells in vitro. RESULTS: Although neither 0.1 mM caffeine nor 0.1 microg/ml of PGE2 alone showed any inhibitory effects on cell proliferation, the combination of caffeine and PGE2 showed significant inhibition. However, in order to have inhibitory effects, both caffeine and PGE2 had to be present at least 72 or 96 hours in the medium. Addition of the endogenous PGE2 synthesis inhibitor, indomethacin, showed no effects on cell proliferation. Neither cAMP-inducing agent IBMX (0.01 mM and 0.1 mM) nor forskolin (0.001 mM) inhibited cell proliferation, but combined with PGE2 these agents strongly inhibited proliferation as was observed with the combination of caffeine and PGE2, suggesting possibly that the increase of intracellular cAMP concentration plays an important role in the inhibitory effects of cell proliferation. CONCLUSIONS: The present data for the first time demonstrate the possible implication of routine caffeine intake in the acceleration of pathological conditions of periodontitis. Thus, we propose that chronic caffeine intake is one of the possible risk factors in the advancement of pathology in the periodontitis patient. Further research in this area is warranted.     

高压氧对牙周炎组织前列腺素的作用及机理分析

目的：探讨高压氧（hyperbaric oxygen,HBO)对鼠牙龈和牙槽骨中前列腺素E2（prostaglandins E2,PGE2）的作用，研究HBO治疗牙周炎的机理。方法：对60只豚鼠进行丝线缝扎和高糖食料喂养形成牙周炎，每天用0．25MPaHBO治疗牙周炎60min ，连续治疗2周，用酶联免疫测定法分析牙龈和牙槽骨中PGE2的含量，观察治疗组与对照组的PGE2变化。结果：对照组鼠牙 龈组织中的PGE2含量为3．21ng/g，牙槽骨中为3．22ng/g；牙周炎形成后牙龈组织和牙槽骨中的PGE2含量均明显升高（P＜0．01）；经HBO治疗后牙龈和牙槽骨中的PGE2含量较牙周炎组分别 降低了62．7％和69．6％，且与牙周炎组差异有极显著性。结论：牙 周炎形成后牙龈和牙槽骨中PGE2含量明显增高；HBO暴露后牙龈和牙槽骨中的PGE2含量均明显降低，且牙槽骨中PGE2的降低程度较牙龈组织更明显。     

Cyclooxygenase-2 inhibitors decrease interleukin-1beta-stimulated prostaglandin E2 and IL-6 production by human gingival fibroblasts

BACKGROUND: Previous work showed that normal and aggressive periodontitis (AgP) gingival fibroblasts produce the bone-resorbing cytokine IL-6. PGE2 is important in regulating IL-6 production. Non-steroidal anti-inflammatory drugs inhibit PG synthesis via COX-1 and/or COX-2 isoenzymes and may inhibit periodontal destruction. COX-2 is induced after cellular activation (i.e., by inflammatory cytokines such as IL-1beta). Little is known about IL-1beta-stimulated AgP fibroblast IL-6 and PGE2 production and their regulation by COX inhibitors. The objective of this study was to determine the effects of COX-2 inhibitors on amounts of PGE2 and IL-6 made by IL-1beta-stimulated gingival fibroblasts. METHODS: Gingival fibroblasts (2.5 x 10(4)) from healthy or severe periodontitis patients were cultured in serum-free medium, with or without IL-1beta (10(-11)M) for 24 hours, with or without the COX-1/2 inhibitor indomethacin or the selective COX-2 inhibitors NS-398, celecoxib, or rofecoxib. PGE2 and IL-6 in culture supernatants were determined by specific enzyme-linked immunosorbent assay (ELISA)s. RESULTS: All of the COX inhibitors caused dose-dependent decreases in IL-1beta-stimulated PGE2, to a maximum of > 90% in all cell lines (P < or = 0.0001). The selective COX-2 inhibitors, but not indomethacin, caused partial (generally up to approximately 60%), dose-dependent decreases in IL-1beta-stimulated IL-6 in all cell lines (P < or = 0.003). When exogenous PGE2 was added concurrently with COX-2 inhibitors before addition of IL-1beta, IL-6 production returned to levels at or approaching that produced by cells exposed only to IL-1beta (P < or = 0.04). CONCLUSION: The results suggest that COX-2 inhibition may be useful in helping to control fibroblast production of IL-6 in patients with severe periodontitis.     

Antimicrobial activity of flurbiprofen and ibuprofen in vitro against six common periodontal pathogens.

Nonsteroidal antiinflammatory drugs (NSAIDs) such as flurbiprofen and ibuprofen, have been shown to inhibit the inflammation and alveolar bone loss associated with chronic destructive periodontal disease. However, the direct effect of NSAIDs on the gingival crevice microflora has not been studied. The purpose of this investigation was to evaluate the antimicrobial activity of ibuprofen and flurbiprofen in vitro on six commonly isolated periodontal pathogens. The bacterial strains evaluated were Actinobacillus actinomycetemcomitans, Bacteroides gingivalis, Bacteroides intermedius, Eikenella corrodens, Fusobacterium nucleatum and Wolinella recta. Pure cultures of these organisms were inoculated into broth, allowed to grow and inoculated again into sheep blood agar plates. For preliminary dose-response studies, antibiotic sensitivity blank disks loaded with 10 microliters of flurbiprofen 250 micrograms, 50 micrograms and 5 micrograms, or ibuprofen 500 micrograms, 50 micrograms and 5 micrograms were placed on the seeded agar plates. Clindamycin 2 micrograms disks were used as positive controls and discs loaded with only drug vehicle served as negative controls. In an attempt to estimate the minimal inhibitory concentrations of these NSAIDs on specific microorganisms, additional experiments employing intermediate drug dosages were also performed. Clindamycin produced large zones of inhibition for all bacterial strains except for Eikenella corrodens which is known to be resistant to the antibiotic and Actinobacillus actinomycetemcomitans which appeared to be only moderately sensitive to the antibiotic. Zones of inhibition were not produced by any of the negative control disks or by the 5 micrograms or 50 micrograms doses of either NSAID.(ABSTRACT TRUNCATED AT 250 WORDS)     

Flurbiprofen in human crevicular fluid analyzed by highperformance liquid chromatography

The aim of this study was to determine whether the non-steroidal anti-inflammatory drug, flurbiprofen, which has been shown to be an inhibitor of alveolar bone loss in human periodontal disease, is present in human crevicular fluid (CF) following oral dosing. A method is described whereby routine high-performance liquid chromatography is used to detect the drug in only 20 microliters of CF. 5 volunteers abstained from toothbrushing for 21 days to induce experimental gingivitis and increase the resting flow of CF. 100 mg of flurbiprofen was taken by each volunteer on d 21-28. On d 21 and 28, serum and CF samples were taken prior to dosing and afterwards at 1, 2, 4 and 6 hours. On d 21 the mean peak concentration of the drug in serum was about 11 micrograms/ml and was found between 1-2 h after dosing. The respective values for CF (d 21) were 0.32 micrograms/ml and 4 h. On d 28 flurbiprofen was detected in both fluids prior to dosing. The mean peak concentrations after dosing had increased to 13.13 micrograms/ml (serum) and 0.46 micrograms/ml (CF) although the levels of the drug in CF remained relatively constant throughout the observation period on d 28. The results indicate that flurbiprofen may be detected in human CF after oral administration and that the levels are in excess of the plasma level, which in beagles has been shown to inhibit alveolar bone loss in periodontal disease.     

Crevicular fluid prostaglandin E levels as a measure of the periodontal disease status of adult and juvenile periodontitis patients

The measurement of crevicular fluid PGE (CF-PGE) as an indicator of periodontal disease status was investigated. The association between CF-PGE levels and the PGE content of the adjacent periodontal tissues was found to be highly significant (P=5.3 × 10⁻⁶). The high correlation (r=0.925) between the log CF-PGE level and the tissue PGE concentration indicates that CF levels can be used to reliably predict tissue levels. The CF-PGE measurements at each periodontal site were found to be highly reproducible. Samples from adult and juvenile periodontitis patients demonstrated that the mean CF-PGE levels were correlated with disease severity, as determined by mean attachment loss. The mean CF-PGE level in juvenile periodontitis patients was almost three-fold higher than that present in adult periodontitis (144.0 ± 28.0 ng/ml vs 57.5 ± 8.7 ng/ml, mean ± S.E., significant at P = 0.002). The use of CF-PGE concentrations as an indicator of disease activity (i.e. longitudinal attachment loss) cannot be demonstrated by this cross-sectional study. However, the CF-PGE measurement has been demonstrated to be a non-invasive, sensitive, reproducible, and reliable reflection of tissue levels of PGE₂. The association of increasing levels of CF-PGE with increased severity and aggressiveness of disease is consistent with PGE as an inflammatory mediator of tissue destruction.     

Production of prostaglandin E2 by polymorphonuclear neutrophils isolated from gingival crevicular fluid and peripheral blood of dogs in periodontal health and disease

We examined PGE2 synthesis using inflamed and non-inflamed GCF PMNs and PB PMNs in the presence and absence of certain stimulators. The basal levels of PGE2 release from GCF PMNs isolated from ligature-induced gingival sulcus with a GI value over 2.2 were significantly lower than those from GCF PMNs isolated from sham operated sites with a GI value below 2.1. Levels were comparable to those from PB PMNs isolated at each experimental period, indicating that the amount of PGE2 synthesized by GCF PMNs is not correlated exactly with the severity of periodontitis. Calcium ionophore A23187 stimulated PGE2 synthesis by all PMN preparations. When compared to those with inflamed and non-inflamed GCF PMNs, stimulation was higher with PB PMNs. However, the chemotactic factor fMLP inhibited the synthesis by inflamed and non-inflamed GCF PMNs. PGE2 synthesis by PB PMNs isolated after periodontal operation was stimulated by the drug, but those cells isolated before the operation did not respond.     

ASC-dependent RIP2 Kinase Regulates Reduced PGE2 Production in Chronic Periodontitis

Levels of prostaglandin E(2) (PGE(2)) and its processing enzyme, prostaglandin-endoperoxide-synthase-2/ cyclooxygenase-2 (PTGS2/COX-2), are elevated in actively progressing periodontal lesions, but suppressed in chronic disease. COX-2 expression is regulated through inflammatory signaling that converges on the mitogen-activated protein kinase (MAPK) pathway. Emerging evidence suggests a role for the inflammatory adaptor protein, ASC/Pycard, in MAPK activation. We postulated that ASC may represent a mediator of the MAPK-mediated regulatory network of PGE(2) production. Using RNAi-mediated gene slicing, we demonstrated that ASC regulates COX-2 expression and PGE(2) production in THP1 monocytic cells following infection with Porphyromonas gingivalis (Pg). Production of PGE(2) did not require the inflammasome adaptor function of ASC, but was dependent on MAPK activation. Furthermore, the MAP kinase kinase kinase CARD domain-containing protein RIPK2 was induced by Pg in an ASC-dependent manner. Reduced ASC and RIPK2 levels were revealed by orthogonal comparison of the expression of the RIPK family in ASC-deficient THP1 cells with that in chronic periodontitis patients. We show that pharmacological inhibition of RIPK2 represses PGE(2) secretion, and RNAi-mediated silencing of RIPK2 leads to diminished MAPK activation and PGE(2) secretion. These findings identify a novel ASC-RIPK2 axis in the generation of PGE(2) that is repressed in patients diagnosed with chronic adult periodontitis.