Meloxicam and indomethacin activity on human matrix metalloproteinases in synovial fluid

Oxaprozin: A new hope in the modulation of matrix metalloproteinase 9 activity

Oxaprozin (4,5-diphenyl-2-oxazolepropionic acid) is a non-steroidal, analgesic and antipyretic propionic acid derivative, whose activity in treating inflammatory disorders is well known. The aim of this study was to investigate the ability of oxaprozin to modulate the activity of matrix metalloproteinase 9 (MMP-9), a zinc-dependent endopeptidase involved in a wide range of physiological and pathological events associated with extracellular matrix (ECM) remodelling. The interaction between oxaprozin and MMP-9 was firstly investigated in silico by molecular docking and analysis with LIGPLOT software. Subsequently, the potential inhibitory activity of oxaprozin against MMP-9 and the possible mechanism of the ligand-enzyme interaction were investigated in vitro. Taking into account the in silico findings, MMP-9 can be considered a potential target of oxaprozin, which seems to be able to chelate the catalytic zinc ion through the nitrogen of the oxazole ring and the carboxylate moiety. Moreover, one of the phenyl rings interact with the S1' inhibitor-binding pocket through hydrophobic interaction. Gelatin zymography and enzymatic inhibition assay confirmed the potential role of oxaprozin as a competitive inhibitor of MMP-9. These observations sound particularly interesting if we consider the pathological role of MMP-9, especially evident in inflammatory conditions and cancer. This work may represent a starting point to improve the understanding of the role of oxaprozin, as well as its structural analogues, in modulating the MMP-9 function.

In vivo effects of meloxicam on inflammatory mediators, MMP activity and cartilage biomarkers in equine joints with acute synovitis

REASONS FOR PERFORMING STUDY

Meloxicam is a commonly used nonsteroidal anti-inflammatory drug in equine practice, but little is known about its in vivo effects on joint inflammation and cartilage turnover.

OBJECTIVES

To study the effects of meloxicam on biomarkers of inflammation, matrix metalloproteinase (MMP) activity, and cartilage biomarkers in joints with experimental synovitis.

METHODS

In a 2-period cross-over study, synovitis was induced at T = 0 h in the L or R intercarpal joint of 6 horses by intraarticular injection of 0.5 ng lipopolysaccharide (LPS). Horses received once daily meloxicam (0.6 mg/kg bwt per os) or placebo starting at post injection hour (PIH) 2, and clinical evaluations as well as blood and synovial fluid (SF) sampling were performed at PIH 0, 8, 24 and 168. Synovial fluid was analysed for prostaglandin E2, bradykinin, substance P, general MMP activity, glycosaminoglycans (GAG), CS846 epitope, type II collagen cleavage fragments (C2C) and type II collagen carboxypropeptide (CPII). Concentrations in meloxicam- vs. placebo-treated joints over time were compared using a linear mixed model.

RESULTS

Lipopolysaccharide injection caused marked transient synovitis without systemic effects. Meloxicam caused a significant reduction in lameness at PIH 8 and 24 and tended to reduce effusion. In addition, meloxicam significantly suppressed SF prostaglandin E2 and substance P release at PIH 8 and bradykinin at PIH 24 compared to placebo treatment. General MMP activity at PIH 8 and 24 was significantly lower in meloxicam- vs. placebo-treated joints, as were GAG, C2C and CPII concentrations at PIH 24.

CONCLUSIONS

Acute transient synovitis leads to substantial increases in SF biomarkers of inflammation, MMP activity and cartilage turnover, which can be significantly suppressed by meloxicam.

POTENTIAL RELEVANCE

Early oral treatment with meloxicam ameliorates not only clinical signs and joint inflammation in acute synovitis, but may also limit inflammation-induced cartilage catabolism.

Gingival crevicular fluid matrix metalloproteinase-8 levels following adjunctive use of meloxicam and initial phase of periodontal therapy

BACKGROUND

The purpose of the present study was to assess the effects of adjunctive meloxicam on the matrix metalloproteinase-8 (MMP-8) levels of gingival crevicular fluid (GCF) in chronic periodontitis patients following the initial phase of periodontal therapy.

METHODS

Twelve chronic periodontitis patients received 7.5 mg meloxicam, and 10 patients received placebo tablets together with scaling and root planing in a 1 x 1 regimen for 10 days. Scaling and root planing were performed on day 3 of drug intake. The MMP-8 levels in GCF samples obtained before and on day 10 of drug intake were determined by using the immunofluorescence assay. Plaque index (PI), papilla bleeding index (PBI), and GCF MMP-8 levels were compared within each patient group, between the 2 patient groups, and also with a clinically healthy control group using non-parametric statistical analyses.

RESULTS

Both meloxicam and placebo groups showed statistically significant reductions in PBI, PI, and GCF MMP-8 levels on day 10 compared to baseline (P<0.01). The GCF MMP-8 level on day 10 in the meloxicam group was similar to the clinically healthy control group (P>0.05), while it was significantly higher in the placebo group (P<0.01). Positive correlations were found between MMP-8 total amounts and PBI scores at baseline and day 10 of drug intake in the patient groups.

CONCLUSIONS

Meloxicam showed a tendency to reduce GCF MMP-8 levels in vivo within the first 10 days when used as an adjunct in the initial phase of periodontal treatment that consists of scaling and root planing. Verification of this effect on collagenase-2 downregulation, as well as on the clinical periodontal parameters in long-term studies using larger test and control groups, is needed to provide further support for the adjunctive use of selective cyclooxygenase (COX)-2 inhibitors in the treatment of chronic periodontitis.