Regulation of matrix metalloproteinase secretion by green tea catechins in a three-dimensional co-culture model of macrophages and gingival fibroblasts.

OBJECTIVES: Elevated levels of matrix metalloproteinases (MMPs) have been associated with the active phases of tissue and bone destruction in periodontitis, an inflammatory disease characterized by a significant breakdown of tooth support. In the present study, we used a three-dimensional (3D) co-culture model of macrophages and gingival fibroblasts to investigate the ability of a green tea extract and its major constituent epigallocatechin-3-gallate (EGCG) to regulate the secretion of MMP-3, -8, and -9. METHODS: The 3D co-culture model was composed of gingival fibroblasts embedded in a type I collagen matrix overlaid with macrophages. Two arbitrary ratios were tested. The ratio composed of 1 macrophage to 10 fibroblasts was used to mimic a slightly inflamed periodontal site while the ratio composed of 10 macrophages to 1 fibroblast was used to mimic a severely inflamed periodontal site. The 3D co-culture model was pre-treated for 2h with either the green tea extract or EGCG. It was then stimulated with Aggregatibacter actinomycetemcomitans lipopolysaccharide (LPS). The model was also first stimulated with LPS for 2h and then incubated with the green tea extract or EGCG. The concentrations of secreted MMP-3, -8, and -9 were quantified by enzyme-linked immunoassays. RESULTS: When the 3D co-culture model was stimulated with A. actinomycetemcomitans LPS, the 10:1 ratio of macrophages to gingival fibroblasts was associated with a highest secretion of MMP-3 and -9 and, to a lesser extent, MMP-8, than the 1:10 ratio. Non-cytotoxic concentrations of the green tea extract or EGCG reduced the basal secretion levels of all three MMPs. A 2-h treatment with the green tea extract or EGCG prior to the stimulation with LPS resulted in a dose-dependent decrease in MMP secretion, with MMP-9 showing the most significant decrease. A decrease in MMP secretion was also observed when the green tea extract or EGCG was added following a 2-h stimulation with LPS. CONCLUSIONS: Our results suggested that green tea catechins, and more specifically EGCG, offer promising prospects for the development of a novel adjunctive treatment for periodontitis because of their ability to decrease the secretion of MMPs, which are important tissue-destructive enzymes produced by mucosal and immune cells.

Association of MMP-8 with obesity, smoking and insulin resistance.

BACKGROUND: Obesity has been recognized as a state of subclinical inflammation resulting in a loss of insulin receptors and decreased insulin sensitivity. We here studied in vivo the role of circulating matrix metalloproteinase-8 (MMP-8) among young healthy twin adults. Also, in vitro analysis of the cleavage of human insulin receptor (INSR) by MMP-8 was investigated as well its inhibition by doxycycline and other MMP-8 inhibitor, Ilomastat/GM6001, which are broad-spectrum MMP inhibitors. MATERIALS AND METHODS: We analysed serum MMP-8 levels by a time-resolved immunofluorometric assay in obese (n = 34), overweight (n = 76) and normal weight (n = 130) twin individuals. The effect of MMP-8 on INSR and the effects of synthetic MMP-8 inhibitors, doxycycline and Ilomastat/GM6001, were studied by SDS-PAGE. RESULTS: We found that in obese individuals relative to normal weight individuals, the serum MMP-8 levels and MMP-8/TIMP-1 ratio were significantly increased (P = 0·0031 and P = 0·031, respectively). Among normal weight and obese individuals, also smoking significantly increases serum MMP-8 and MMP-8/TIMP-1 ratio. In vitro, we found that INSR was degraded by MMP-8 and this was inhibited by doxycycline and Ilomastat/GM6001. CONCLUSIONS: Obesity associated with elevated circulating MMP-8 found among young adults may contribute to progression of insulin resistance by cleaving INSR. This INSR cleavage by MMP-8 can be inhibited by synthetic MMP-8 inhibitors such as doxycycline. In addition to obesity, also smoking independently explained increased MMP-8 levels. Our results suggest that MMP-8 is an essential mediator in systemic subclinical inflammatory response in obesity, and a potential drug target.

A Novel Chemically Modified Curcumin "Normalizes" Wound-Healing in Rats with Experimentally Induced Type I Diabetes: Initial Studies.

Introduction. Impaired wound-healing in diabetics can lead to life-threatening complications, such as limb amputation, associated in part with excessive matrix metalloproteinase- (MMP-) mediated degradation of collagen and other matrix constituents. In the current study, a novel triketonic chemically modified curcumin, CMC2.24, was tested for efficacy in healing of standardized skin wounds in streptozotocin-induced diabetic rats. Initially, CMC2.24 was daily applied topically at 1% or 3% concentrations or administered systemically (oral intubation; 30 mg/kg); controls received vehicle treatment only. Over 7 days, the diabetics exhibited impaired wound closure, assessed by gross and histologic measurements, compared to the nondiabetic controls. All drug treatments significantly improved wound closure with efficacy ratings as follows: 1% 2.24 > systemic 2.24 > 3% 2.24 with no effect on the severe hyperglycemia. In subsequent experiments, 1% CMC2.24 "normalized" wound-healing in the diabetics, whereas 1% curcumin was no more effective than 0.25% CMC2.24, and the latter remained 34% worse than normal. MMP-8 was increased 10-fold in the diabetic wounds and topically applied 1% (but not 0.25%) CMC2.24 significantly reduced this excessive collagenase-2; MMP-13/collagenase-3 did not show significant changes. Additional studies indicated efficacy of 1% CMC2.24 over more prolonged periods of time up to 30 days.

Cigarette Smoke-Induced Lung Disease Predisposes to More Severe Infection with Nontypeable Haemophilus influenzae: Protective Effects of Andrographolide.

Cigarette smoke (CS) is associated with many maladies, one of which is chronic obstructive pulmonary disease (COPD). As the disease progresses, patients are more prone to develop COPD exacerbation episodes by bacterial infection, particularly to nontypeable Haemophilus influenza (NTHi) infection. The present study aimed to develop a CS-exposed mouse model that increases inflammation induced by NTHi challenge and investigate the protective effects of andrographolide, a bioactive molecule with anti-inflammatory and antioxidant properties isolated from the plant Andrographis paniculata. Female BALB/c mice exposed to 2 weeks of CS followed by a single intratracheal instillation of NTHi developed increased macrophage and neutrophil pulmonary infiltration, augmented cytokine levels, and heightened oxidative damage. Andrographolide effectively reduced lung cellular infiltrates and decreased lung levels of TNF-α, IL-1ß, CXCL1/KC, 8-OHdG, matrix metalloproteinase-8 (MMP-8), and MMP-9. The protective actions of andrographolide on CS-predisposed NTHi inflammation might be attributable to increased nuclear factor erythroid-2-related factor 2 (Nrf2) activation and decreased Kelch-like ECH-associated protein 1 (Keap1) repressor function, resulting in enhanced gene expression of antioxidant enzymes including heme oxygenase-1 (HO-1), glutathione reductase (GR), glutathione peroxidase-2 (GPx-2), glutamate-cysteine ligase modifier (GCLM), and NAD(P)H quinone oxidoreductase 1 (NQO1). Taken together, these findings strongly support a therapeutic potential for andrographolide in preventing lung inflammation caused by NTHi in cigarette smokers.

Periodontal Dressing as an Adjunct after Scaling and Root Planing--A Useful Preventive Tool?

PURPOSE: To determine the preventive effect of a periodontal dressing containing colophony, zinc oxide and magnesium oxide applied after scaling and root planing on clinical variables, subgingival bacteria and local immune response in patients with chronic periodontitis. MATERIALS AND METHODS: In this randomised prospective clinical study, 28 volunteers with generalised moderate chronic periodontitis were treated with full-mouth scaling in a split-mouth design. In the test quadrants, the periodontal dressing was applied during the first three days. At baseline and after 6 and 12 weeks, probing pocket depth (PD), attachment level (AL) and bleeding on probing (BOP) were recorded, and subgingival plaque samples were taken for laboratory analysis. RESULTS: In both groups, PD, AL and BOP were significantly reduced (p=0.001). BOP was significantly lower in the control than the test group after 6 weeks (p=0.046). Significantly reduced bacterial counts of Porphyromonas gingivalis were found in the control group after 12 weeks (p=0.013). No differences were found for the microbiological results between the groups. After 12 weeks, interleukin (IL)-8 and matrix metalloproteinase (MMP)-8 were significantly higher in the test group (p=0.023 and p=0.003, respectively). CONCLUSION: The adjunctive application of a periodontal dressing had no additional preventive effect on clinical data 12 weeks after scaling and root planing.

Hydrocortisone supresses inflammatory activity of metalloproteinase-8 in carotid plaque.

OBJECTIVE: Matrix metalloproteinases are inflammatory biomarkers involved in carotid plaque instability. Our objective was to analyze the inflammatory activity of plasma and carotid plaque MMP-8 and MMP-9 after intravenous administration of hydrocortisone. METHODS: The study included 22 patients with stenosis ≥ 70% in the carotid artery (11 symptomatic and 11 asymptomatic) who underwent carotid endarterectomy. The patients were divided into two groups: Control Group - hydrocortisone was not administered, and Group 1 - 500 mg intravenous hydrocortisone was administered during anesthetic induction. Plasma levels of MMP-8 and MMP-9 were measured preoperatively (24 hours before carotid endarterectomy) and at 1 hour, 6 hours and 24 hours after carotid endarterectomy. In carotid plaque, tissue levels of MMP-8 and MMP-9 were measured. RESULTS: Group 1 showed increased serum levels of MMP- 8 (994.28 pg/ml and 408.54 pg/ml, respectively; P=0.045) and MMP-9 (106,656.34 and 42,807.69 respectively; P=0.014) at 1 hour after carotid endarterectomy compared to the control group. Symptomatic patients in Group 1 exhibited lower tissue concentration of MMP-8 in comparison to the control group (143.89 pg/ml and 1317.36 respectively; P=0.003). There was a correlation between preoperative MMP-9 levels and tissue concentrations of MMP-8 (P=0.042) and MMP-9 (P=0.019) between symptomatic patients in the control group. CONCLUSION: Hydrocortisone reduces the concentration of MMP- 8 in carotid plaque, especially in symptomatic patients. There was an association between systemic and tissue inflammation.

Effect of nonsurgical periodontal treatment in conjunction with either systemic administration of amoxicillin and metronidazole or additional photodynamic therapy on the concentration of matrix metalloproteinases 8 and 9 in gingival crevicular fluid in patients with aggressive periodontitis.

BACKGROUND: To evaluate in patients with aggressive periodontitis (AgP) the effect of nonsurgical periodontal treatment in conjunction with either additional administration of systemic antibiotics (AB) or application of photodynamic therapy (PDT) on the gingival crevicular fluid (GCF) concentration of matrix metalloproteinases 8 and 9 (MMP-8 and -9). METHODS: Thirty-six patients with AgP were included in the study. Patients were randomly assigned to treatment with either scaling and root planing (SRP) followed by systemic administration of AB (e.g. Amoxicillin + Metronidazole) or SRP + PDT. The analysis of MMP-8 and -9 GCF concentrations was performed at baseline and at 3 and 6 months after treatment. Nonparametric U-Mann-Whitney test was used for comparison between groups. Changes from baseline to 3 and 6 months were analyzed with the Friedman's ANOVA test with Kendall's index of consistency. RESULTS: In the AB group, patients showed a statistically significant (p = 0.01) decrease of MMP-8 GCF level at both 3 and 6 months post treatment. In the PDT group, the change of MMP-8 GCF level was not statistically significant. Both groups showed at 3 and 6 months a decrease in MMP-9 levels. However, this change did not reach statistical significance. CONCLUSIONS: Within the limits of the present study, it may be suggested that in patients with AgP, nonsurgical periodontal therapy in conjunction with adjunctive systemic administration of amoxicilin and metronidazole is more effective in reducing GCF MMP-8 levels compared to the adjunctive use of PDT.

Possible implications of Ni(II) on oral IL-1ß-induced inflammatory processes.

OBJECTIVES: Nickel (Ni) is one of the main metal elements in orthodontic and prosthetic devices. Different effects of Ni are described ranging from an induction of local inflammation to allergy and cancerous/mutagenic properties. Inflammatory reactions are frequently observed in the oral cavity, but the interrelationship of Ni with those events is still unknown. Therefore, we focused on the impact of Ni on inflammation in vitro. METHODS: In accordance to previous immersion tests of our lab, human gingival fibroblasts (HGFs) (n=6) were exposed to a pro-inflammatory environment using interleukin-1 beta (IL-1ß) and additionally stimulated with different Ni(II) concentrations (400 and 4000ng/ml). At varying time points the expression of pro- and anti-inflammatory as well as matrix degeneration proteins, i.e. MMPs, were analyzed. Furthermore, proliferation assays, wound healing tests and the detection of NF-κB activation were conducted. Unstimulated HGFs served as control. RESULTS: Our experiments showed that low clinical average Ni(II) levels did not alter pro-inflammatory cytokines significantly compared to control (p>0.05). Instead, a 10-fold higher dose up-regulated these mediators significantly in a time-dependent manner (p<0.01). This was even more pronounced combining both Ni(II) concentrations with an inflammatory condition (p<0.001), MMP expressions were in line with our findings (p<0.001). The mRNA data were supported by proliferation and wound closure assays (p<0.001). However, the combination of both stimuli induced contradictory results. Analyzing NF-κB activation revealed that our results may be in part attributed to NF-κB. SIGNIFICANCE: Our in vitro study implicated that Ni(II) has various modifying effects on IL-1ß-induced inflammatory processes depending on the concentration.

The effect of adjunctive chlorhexidine mouthrinse on GCF MMP-8 and TIMP-1 levels in gingivitis: a randomized placebo-controlled study.

BACKGROUND: The aim of the present study was to evaluate the effect of adjunctive chlorhexidine (CHX) mouthrinse on gingival crevicular fluid (GCF) MMP-8 and TIMP-1 levels in plaque-associated gingivitis. METHODS: A total of 50 gingivitis patients were included in the present study. In addition to daily plaque control, CHX group rinsed with CHX, while placebo group rinsed with placebo mouthrinse for 4 weeks. GCF samples were collected, and clinical parameters including plaque index, papillary bleeding index, calculus index and pocket depth were recorded at baseline and 4 weeks. GCF MMP-8 and TIMP-1 levels were determined by immunofluorometric assay (IFMA) and enzyme-linked immunosorbent assay (ELISA), respectively. RESULTS: In both groups, GCF MMP-8 levels of anterior and posterior sites at four weeks were not different from baseline (p > 0.05). There were no significant differences in GCF MMP-8 levels between the study groups at four weeks (p > 0.05). GCF TIMP-1 levels of anterior and posterior sites at four weeks were higher compared to baseline in both groups (p < 0.05). There was no significant difference in GCF TIMP level between the study groups at four weeks (p > 0.05). CONCLUSIONS: CHX usage had no significant effects on the GCF MMP-8 and TIMP-1 levels in plaque-associate gingivitis. However, daily plaque control resulted in the increase of GCF TIMP-1 levels regardless of CHX usage.

The inhibitory effect of proanthocyanidin on soluble and collagen-bound proteases.

OBJECTIVE: This study evaluated the inhibitory effect of proanthocyanidin (PA), a natural collagen cross-linker, on soluble and matrix-bound proteases, which are responsible for progressive degradation of exposed collagen fibrils within the hybrid layer and resin-dentine bond failure over time. METHODS: The inhibitory effects of PA (1%, 2%, 3%, 4.5% and 6%) on soluble recombinant matrix metalloproteinases (MMP-2, -8 and -9) and cysteine cathepsins (cathepsin B and K) were evaluated using MMP and cysteine cathepsins fluorometric assay kits. Chlorhexidine (CHX) was used as an inhibitor control. The effect of PA on endogenous matrix-bound proteases was examined by determining the change in dry mass of demineralized dentine beams and solubilized collagen peptides over 30 days. Two-way ANOVA and Tukey multiple comparison tests were used to analyze the effect of PA and proteases on the percentage inhibition of soluble proteases (α=0.05). Kruskal-Wallis one-way ANOVA and Dunn's multiple comparison tests were used to analyse the effect of PA on loss of dry mass and hydroxyproline content over time (α=0.05). RESULTS: Proanthocyanidin inactivated more than 90% of soluble recombinant MMP-2, -8 and -9 and around 75-90% of cysteine cathepsin B and K, which was significantly higher than CHX (P<0.05). The inhibition of endogenous proteases by PA increased in a dose-dependent manner. The loss of dry mass and hydroxyproline release in the medium over time was the lowest in dentine beams pretreated with PA

Protective mechanisms of simvastatin in experimental periodontal disease.

BACKGROUND: Simvastatin is a cholesterol-lowering drug whose pleiotropic effects may have a therapeutic impact on bone. This study evaluates the effect of simvastatin on rats subjected to experimental periodontal disease. METHODS: Periodontitis was induced by ligature placement around the maxillary left second molar of rats for 11 days. Groups of six animals received oral saline or simvastatin (3, 10, and 30 mg/kg/day) until sacrifice on day 11. Alveolar bone loss was determined by macroscopic and histologic examination. The serum levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), and total alkaline phosphatase (TAP) were evaluated. Gingival myeloperoxidase activity and gingival levels of interleukin-1ß (IL-1ß), tumor necrosis factor-α, IL-10, reduced glutathione, malonaldehyde, and nitrate/nitrite were analyzed to investigate oxidative stress and inflammation. Expression of inducible nitric oxide synthase (iNOS), matrix metalloproteinases 1 and 8 (MMP-1 and -8), bone morphogenetic protein-2 (BMP-2), receptor activator of nuclear factor κB (RANK), RANK ligand (RANKL), and osteoprotegerin (OPG) were also investigated by immunohistochemistry to assess bone turnover and metabolism. Immunofluorescence microscopy was used to confirm the expression of RANKL in rats' maxillae. RESULTS: Treatment with simvastatin improved alveolar bone loss within all of the parameters studied, thus demonstrating anti-inflammatory and antioxidant activity. Simvastatin reduced expression of iNOS, MMP-1 and -8, RANK, and RANKL and increased BMP-2 and OPG levels in the periodontal tissue. Simvastatin (30 mg/kg) increased TAP activity on day 11 compared with the saline group. No differences were found in the levels of AST and ALT in any of the groups studied. CONCLUSION: The present data suggest that simvastatin prevents inflammatory bone resorption in experimental periodontitis, which may be mediated by its anti-inflammatory and antioxidant properties.

Endoplasmic reticulum stress modulates nicotine-induced extracellular matrix degradation in human periodontal ligament cells.

BACKGROUND AND OBJECTIVE: Tobacco smoking is considered to be one of the major risk factors for periodontitis. For example, about half the risk of periodontitis can be attributable to smoking in the USA. It is evident that smokers have greater bone loss, greater attachment loss and deeper periodontal pockets than nonsmoking patients. It has recently been reported that endoplasmic reticulum (ER) stress markers are upregulated in periodontitis patients; however, the direct effects of nicotine on ER stress in regard to extracellular matrix (ECM) degradation are unclear. The purpose of this study was to examine the effects of nicotine on cytotoxicity and expression of ER stress markers, selected ECM molecules and MMPs, and to identify the underlying mechanisms in human periodontal ligament cells. We also examined whether ER stress was responsible for the nicotine-induced cytotoxicity and ECM degradation. MATERIAL AND METHODS: Cytotoxicity and cell death were measured by 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyltetrazolium bromide assay and flow cytometric annexin V and propidium iodide staining. The mRNA and protein expressions of MMPs and ER markers were examined by RT-PCR and western blot analysis. RESULTS: Treatment with nicotine reduced cell viability and increased the proportion of annexin V-negative, propidium iodide-positive cells, an indication of cell death. Nicotine induced ER stress, as evidenced by survival molecules, such as phosphorylated protein kinase-like ER-resident kinase, phosphorylated eukaryotic initiation factor-2α and glucose-regulated protein-78, and apoptotic molecules, such as CAAT/enhancer binding protein homologous protein (CHOP). Nicotine treatment led to the downregulation of ECM molecules, including collagen type I, elastin and fibronectin, and upregulation of MMPs (MMP-1, MMP-2, MMP-8 and MMP-9). Inhibition of ER stress by salubrinal and transfection of CHOP small interfering RNA attenuated the nicotine-induced cell death, ECM degradation and production of MMPs. Salubrinal and CHOP small interfering RNA inhibited the effects of nicotine on the activation of Akt, JNK and nuclear factor-κB. CONCLUSION: These results indicate that nicotine-induced cell death is mediated by the ER stress pathway, involving ECM degradation by MMPs, in human periodontal ligament cells.

Enamel matrix derivative promotes superoxide production and chemotaxis but reduces matrix metalloproteinase-8 expression by polymorphonuclear leukocytes.

BACKGROUND: Polymorphonuclear leukocyte (PMN) is the predominant innate immune cell type activated in acute inflammation. The aim of this study is to determine the impact of enamel matrix derivative (EMD) on superoxide (O(2)(-)) generation, chemotaxis, and matrix metalloproteinase-8 (MMP-8) secretion by PMN in vitro to better understand the role of EMD in surgical wound healing. METHODS: PMNs were isolated from healthy volunteers (n = 14). O(2)(-) generation was measured using a cytochrome c reduction assay. Chemotaxis was measured in a modified Boyden chamber. MMP-8 secretion was analyzed by Western blotting. A relative density method was used to determine the percentage of MMP-8 released from the PMNs in relation to the total cellular MMP-8 content. RESULTS: O(2)(-) generation was significantly elevated when PMNs were stimulated with EMD (200 µg/mL) (P <0.01). Secondary stimulation of PMNs with 1 µM N-formyl-methionyl-leucyl-phenylalanine (fMLP) triggered earlier and more sustained O(2)(-) generation with EMD. EMD significantly increased PMN chemotactic activity (P <0.05). Combined stimulation with EMD plus fMLP resulted in significantly higher chemotaxis compared to fMLP alone (P <0.05). Conversely, EMD did not induce MMP-8 secretion from PMNs. MMP-8 secretion by PMNs in response to fMLP or serum-opsonized zymosan stimulation was significantly inhibited by EMD (P <0.05). CONCLUSIONS: EMD has specific, differential actions on PMNs that suggest potential for enhancement of wound healing, bacterial and tissue debris clearance (O(2)(-) generation and chemotaxis), and suppression of tissue damage and degradation (MMP-8 ). Together, the data suggest that EMD enhances wound healing and reduces inflammation.

Cigarette smoke extract induces select matrix metalloproteinases and integrin expression in periodontal ligament fibroblasts.

BACKGROUND: The periodontal ligament (PDL) is the connective tissue that anchors the cementum of the teeth to the alveolar bone. PDL fibroblasts are responsible for the production of collagen and remodeling of the PDL. Periodontal disease is increased among smokers in both incidence and severity. This study examines the direct effect of smoking on PDL fibroblasts and their production of various matrix components and remodeling enzymes. METHODS: PDL cells were plated for 1 day and then treated with various concentrations of cigarette smoke extract (CSE). Survival of PDL cells was quantified after exposure to CSE, and their ability to contract three-dimensional collagen gels was examined. Changes in transcript expression after CSE treatment was compared using reverse transcription-polymerase chain reaction analysis for matrix metalloproteinases (MMPs), collagens, and integrins. RESULTS: Treatment with CSE-induced cell death at concentrations of ≥5%. PDL-cell-induced collagen gel contraction was reduced at concentrations of 1.5% CSE. Treatment with CSE selectively increased the expression of collagen Vα3 and decreased collagen XIα1. CSE increased the expression of MMP1 and MMP3 and, to a lesser extent, MMP2 and MMP8. CSE also increased the expression of integrins α1, α2, and α10 (collagen receptors) and α9 (a tenascin receptor). CONCLUSIONS: This study shows that cigarette smoking has local effects on the cells of the PDL. CSE reduced survival of PDL cells and their ability to contract collagen matrices. CSE also altered the expression of molecules known to provide the structural integrity of the ligament by altering collagen synthesis and remodeling as well as cell adhesion.

Rheumatoid arthritis and salivary biomarkers of periodontal disease.

AIM: To test the hypothesis that rheumatoid arthritis (RA) influenced levels of salivary biomarkers of periodontal disease. METHODS: Medical assessments, periodontal examinations and pain ratings were obtained from 35 RA, 35 chronic periodontitis and 35 age- and gender-matched healthy controls in a cross-sectional, case-controlled study. Unstimulated whole saliva samples were analysed for interleukin-1ß (IL-1ß), matrix metalloproteinase-8 (MMP-8) and tumour necrosis factor-α (TNF-α) concentrations. RESULTS: The arthritis and healthy groups had significantly less oral disease than the periodontitis group (P<0.0001), with the arthritis group having significantly more sites bleeding on probing (BOP) than matched controls (P=0.012). Salivary levels of MMP-8 and IL-1ß were significantly elevated in the periodontal disease group (P<0.002), and IL-1ß was the only biomarker with significantly higher levels in the arthritis group compared with controls (P=0.002). Arthritis patients receiving anti-TNF-α antibody therapy had significantly lower IL-1ß and TNF-α levels compared with arthritis patients not on anti-TNF-α therapy (P=0.016, 0.024) and healthy controls (P<0.001, P=0.011), respectively. CONCLUSION: RA patients have higher levels of periodontal inflammation than healthy controls, i.e., an increased BOP. Systemic inflammation appears to influence levels of select salivary biomarkers of periodontal disease, and anti-TNF-α antibody-based disease-modifying therapy significantly lowers salivary IL-1ß and TNF-α levels in RA.

Effects of scaling and root planing and subantimicrobial dose doxycycline on gingival crevicular fluid levels of matrix metalloproteinase-8, -13 and serum levels of HsCRP in patients with chronic periodontitis.

BACKGROUND: This study evaluates the efficacy of subantimicrobial dose doxycycline (SDD) in conjunction with scaling and root planing (SRP) on gingival crevicular fluid (GCF) levels of matrix metalloproteinase (MMP)-8 and -13 and on serum levels of high-sensitivity C-reactive protein (HsCRP) in patients with chronic periodontitis (CP). METHODS: A total of 41 patients with CP and 17 healthy individuals were included in this randomized controlled trial. CP patients were randomly distributed into two groups. Study groups were established as Group I with SRP+placebo, Group II with SRP+SDD, and Group III as control. All CP patients received two regimens of SRP and Group II patients also received SDD for 6 weeks. At baseline and 6 weeks, GCF and blood were collected and clinical indices were recorded. The HsCRP level was assayed in the plasma on a nephelometer. The GCF levels of MMPs were assayed by an enzyme-linked immunosorbent assay. RESULTS: Statistically significant differences in plaque index, gingival index (GI), probing depth (PD), GCF volumes, GCF MMP levels, and serum levels of HsCRP between pre-treatment and post-treatment were noted in both groups. Between groups there was a statistically significant decrease in PD, GI, and GCF levels of MMP-8 favoring the group receiving SDD adjunctive to SRP (P <0.05). CONCLUSION: In this study, greater improvement was detected for PD, GI, and GCF levels of MMP-8 when using SRP+SDD compared to SRP+placebo.

Association of gingival crevicular fluid biomarkers during periodontal maintenance with subsequent progressive periodontitis.

BACKGROUND: The analysis of biomarkers in gingival crevicular fluid (GCF) may be helpful in forecasting patient vulnerability to future attachment loss. The purpose of this study is to correlate GCF biomarkers of inflammation and bone resorption with subsequent periodontal attachment and bone loss in a longitudinal trial of a matrix metalloproteinase (MMP) inhibitor. METHODS: GCF was collected from two periodontal pockets (mean +/- SD: 5.1 +/- 1.0 mm) at baseline and annually in postmenopausal females with moderate to advanced periodontitis undergoing periodontal maintenance every 3 to 4 months during a 2-year double-masked, placebo-controlled, randomized clinical trial of subantimicrobial dose doxycycline (SDD; 20 mg two times a day). Subjects were randomized to SDD (n = 64) or a placebo (n = 64). GCF was analyzed for the inflammation markers interleukin (IL)-1beta (using enzyme-linked immunosorbent assay), total collagenase activity (using hydrolysis of a synthetic octapeptide), and MMP-8 (using a Western blot) and the bone-resorption marker carboxyterminal telopeptide cross-link fragment of type I collagen (ICTP) (using a radioimmunoassay). Generalized estimating equations were used to associate these biomarkers, categorized into tertiles, with subsequent clinical attachment (using an automated disk probe) or interproximal bone loss (using radiography). Odds ratio (OR) values compared highest to lowest tertile groups. RESULTS: Increases in GCF IL-1beta and MMP-8 during the first year of periodontal maintenance were associated with increased odds of subsequent (year 2) periodontal attachment loss (OR = 1.67; P = 0.01 and OR = 1.50; P = 0.02, respectively) driven by the placebo group. Elevated baseline ICTP was also associated with increased odds of 1- and 2-year loss of alveolar bone density (OR = 1.98; P = 0.0001) in the placebo group, not the SDD group, and a loss of bone height (OR = 1.38; P = 0.06), again driven by the placebo group. CONCLUSION: These data support the hypothesis that elevated GCF biomarkers of inflammation and bone resorption from a small number of moderate/deep sites have the potential to identify patients who are vulnerable to progressive periodontitis, and SDD may modify that risk.

Effects of inhaled corticosteroids on metalloproteinase-8 and tissue inhibitor of metalloproteinase-1 in the airways of asthmatic children.

BACKGROUND: The effects of corticosteroids on the level and expression of matrix metalloproteinase-8 (MMP-8; collagenase-2) and tissue inhibitors of metalloproteinases (TIMPs) in airway tissue are poorly characterized in vivo. METHODS: We compared MMP-8 and TIMP-1 levels in induced sputum and their expression in airway inflammatory cells of healthy children (n = 27) and of children with newly diagnosed asthma with mild (n = 20) or moderate symptoms (n = 19), before and after 6 months of treatment with inhaled budesonide. RESULTS: At baseline, MMP-8 was higher in asthmatic children with moderate symptoms, TIMP-1 was lower and the MMP-8/TIMP-1 ratio was higher in both groups of asthmatic children compared with controls. Inhaled budesonide increased TIMP-1 levels in both groups of asthmatic children and normalized the MMP-8/TIMP-1 ratio, and this paralleled the improvement in forced expiratory volume in 1 s in children with mild symptoms. At baseline, asthmatic children had significantly more MMP-8-positive macrophages than control children, whereas the number of TIMP-1-positive macrophages was almost the same. Budesonide decreased the percentage of MMP-8-positive macrophages and increased that of TIMP-1-positive macrophages; these changes were significant in asthmatic children with mild symptoms. CONCLUSIONS: Inhaled budesonide normalized the MMP-8/TIMP-1 ratio in asthmatic children by upregulation of TIMP-1 production and downregulation of MMP-8 production by airway macrophages. This change may be a biochemical marker of an effect on airway inflammation and possibly of an ongoing remodeling process that should be further investigated using biopsy specimens.

Effect of clindamycin treatment on vaginal inflammatory markers in pregnant women with bacterial vaginosis and a positive fetal fibronectin test.

OBJECTIVE: To compare the levels of interleukin (IL)-1beta, IL-6, and matrix metalloproteinase (MMP)-8 in the vaginal secretions of pregnant women with a positive fetal fibronectin (fFN) test result with or without asymptomatic bacterial vaginosis (BV) before and after treatment with oral clindamycin. METHODS: A prospective cohort study was conducted among 43 pregnant women with a positive fFN test result. All patients were treated with clindamycin, and the pre- and post-treatment levels of IL-1beta, IL-6, and MMP-8 were compared. RESULTS: Before treatment, levels of IL-1beta and MMP-8 were significantly higher in women with BV compared with women without BV (P<0.05). Vaginal levels of IL-1beta and IL-6, but not MMP-8, decreased after treatment in pregnant women with BV. CONCLUSIONS: The inability of clindamycin to decrease MMP-8 vaginal levels may explain why it is ineffective in reducing preterm birth in pregnant women with positive fFN and BV.

Effect of smoking, abstention, and nicotine patch on epidermal healing and collagenase in skin transudate.

Delayed wound healing may explain postoperative tissue and wound dehiscence in smokers, but the effects of smoking and smoking cessation on the cellular mechanisms remain unclear. Suction blisters were raised in 48 smokers and 30 never smokers. The fluid was retrieved and the epidermal roof was excised. Transepidermal water loss (TEWL) was measured after 2, 4, and 7 days. Then, the smokers were randomized to continuous smoking or abstinence with a transdermal nicotine patch or a placebo by concealed allocation. The sequence was repeated after 4, 8, and 12 weeks in all smokers and abstainers and in 6 never smokers. Matrix metalloproteinase (MMP)-8 and MMP-1 levels in suction blister fluid were assessed by an enzyme-linked immunosorbent assay. Random-effects models for repeated measurements were applied and p< or =0.05 was considered significant. One week after wounding the TEWL was 17.20 (14.47-19.92) g/cm(2) hour (mean, 95% CI) in smokers and 13.89 (9.46-18.33) in never smokers (p<0.01). In abstinent smokers TEWL was 18.95 (15.20-22.70)(p<0.01, when compared with smokers). In smokers, MMP-8 was 36.4 (24.3-48.5) ng/mL (mean, 95% CI) and 15.2 (1.4-30.2) ng/mL in never smokers (p<0.01). Abstinent smokers' MMP-8 level was 21.2 ng/mL (6.6-43.0) (p=0.02, when compared with smokers). MMP-1 was unaffected by smoking and abstention. Transdermal nicotine patch did not affect any parameter. We conclude that smoking attenuates epidermal healing and may enhance extracellular matrix degradation. Three months of abstinence from smoking does not restore epidermal healing, whereas 4 weeks of abstinence normalizes suction blister MMP-8 levels. These findings suggest sustained impaired wound healing in smokers and potential reversibility of extracellular matrix degradation.