Can non-steroidal anti-inflammatory drugs act as metalloproteinase modulators? An in-vitro study of inhibition of collagenase activity

Condylar dysfunctional remodeling and recortication: a case-control study

BACKGROUND

Temporo-mandibular disorders (TMD) is a collective term comprehending different clinical issues involving masticatory muscles, temporo-mandibular joint (TMJ) and other associated structures. TMD diagnosis is not made for its pathogenesis or etiology, but mainly on clinical symptoms. Primary dysfunction develops mostly on four factors: individual predisposition, high psychomotor activity (due to stress or parafunction), occlusal instability and low or absent tissue adaptation capability. On the other hand, secondary disorders can be caused by hereditary or congenital diseases, rheumatic inflammatory diseases, autoimmune and tumoral diseases. During their function, the condyles undergo a structural adaptive and physiological remodeling, but when mechanical stress exceeds adaptive capability, dysfunctional remodeling phenomena may occur. It is characterized by significant condylar morphological modifications at the level of the head of the condyle (smaller condyle), break of cortical integrity and reduced mandibular ramus height with subsequent mandibular retrusion and articular function alteration. The aim of this study is to compare condylar recortication amount, and pain reduction after two different therapeutic protocols.

METHODS

This is a case-control study. Twenty TMD patients were chosen and each of them underwent a documentation protocol including extraoral and intraoral photographs, dental casts, casts mounting on the articulator to evaluate CPI (CO-CR discrepancy index) and cone beam computed tomography (CBCT) of the mandibular condyles taken in closed mouth position. For the radiographic evaluation, a Planmeca ProMax 3D Mid system was utilized with an acquiring volume of 80×80 mm dimension, exposition 90 kV, 10.0 mA, 12 seconds with a DAP (Dose Area Product) of 1094 mGy·cm2 for each condyle. The acquired volume was elaborated by the Planmeca Romexis software v. 3.2.0.R and TMJ module. Seven coronal cuts and 10 sagittal cuts were performed on the head of the condyle to highlight the amount of cortication, before and after the application of two different therapeutic protocols. Protocol number 1 (N.=10 patients) included the exclusive use of a splint, while protocol number 2 (N.=10 patients) included the use of a splint associated with pharmacological therapy (NSAIDs, antioxidant, omega 3). The revaluation was performed on asymptomatic patient after a period of 6-8 months. The pain for each patient was assessed by a Visual Analogue Scale (VAS) from 0 to 10, 0 meaning no pain and 10 the worst pain ever felt. The VAS was evaluated after 10 days from the beginning of the treatment, after 3 months and after 8 months at the end of the treatment. Statistical analyses were carried using a χ2 test (P value <0.05).

RESULTS

No significant differences in the amount of cortication were found in the radiographic revaluation between the two different therapeutic protocols, even though it was noticed that the use of medicaments brought to a resolution of the symptoms in a shorter period of time (P=0.00001 after 10 days; P=0.0251 after 3 months).

CONCLUSIONS

According to this study, pharmacological protocol in the therapy of TMD does not seem to affect condylar cortication. Medicaments although seem to accelerate the disappearance of clinic symptomatology, but more researches are needed to valid these findings.

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.

Nimesulide -- a multifactorial approach to inflammation and pain: scientific and clinical consensus

BACKGROUND

This paper summarises the outcome from a consensus meeting, held in Rome on 5 October 2005, that aimed to review the state of the art regarding the non-steroidal anti-inflammatory drug (NSAID) nimesulide, with reference to its chemical, pharmacokinetic, pharmacological and clinical characteristics.

SCOPE

The meeting aimed to provide a continuous and up-to-date evaluation of the clinical and safety profile of nimesulide, and of its role in the treatment of inflammatory pain, in light of existing therapeutic alternatives, through a revision and critical discussion on the information available on the drug among authoritative experts in different fields of medical science.

FINDINGS

The members of the Consensus Report Group on Nimesulide (CRGN) recognised that nimesulide is an NSAID which exerts its analgesic, anti-inflammatory and antipyretic activities thanks to unique chemical and pharmacokinetic characteristics, and to a multifactorial mechanism of action, which goes beyond its preferential inhibitory activity on the COX-2 enzyme. Nimesulide was found to be at least as effective, or superior, to placebo and other NSAIDs, with a particularly fast onset of analgesic action. The safety profile is in line with that expected from the class, with evidence of a better gastrointestinal safety profile.

CONCLUSIONS

Based on the available evidence, the CRGN concluded that nimesulide remains an effective and safe therapeutic choice for the treatment of various painful inflammatory conditions, with a rapid onset of analgesic activity and an overall positive benefit/risk profile.

Comparative Effect of Nimesulide and??Ibuprofen on the Urinary Levels of??Collagen Type II C-Telopeptide Degradation Products and on the Serum Levels of Hyaluronan and Matrix Metalloproteinases-3 and -13 in??Patients with Flare-Up of Osteoarthritis

BACKGROUND AND AIM

Because in vitro studies have shown that nimesulide not only preferentially inhibits COX-2 but also reduces the action/release of pro-inflammatory cytokines, down-regulates the synthesis and/or activity of collagenase(s), and releases reactive oxygen species and other toxic substances from neutrophils, this study investigated whether nimesulide and ibuprofen could affect levels of biochemical markers of joint inflammation and collagen catabolism in patients with flare-up of knee or hip osteoarthritis.

METHODS

Ninety patients were included in this randomised, prospective, single- blind study. They received either nimesulide (n = 45) or ibuprofen (n = 45) for a 4-week treatment period. The following parameters were analysed by ELISA: urinary levels of C-terminal cross-linking telopeptide of type II collagen (CTX-II), a marker of type II collagen breakdown; serum levels of hyaluronan (HA), a marker of synovial inflammation and hyperplasia; and circulating levels of stromelysin-1 (matrix metalloproteinase-3 [MMP-3]), collagenase-1 (MMP-1) and collagenase-3 (MMP-13). Statistical analysis used was ANOVA.

RESULTS

At the end of the treatment period, nimesulide but not ibuprofen markedly reduced the urinary levels of CTX-II (p < 0.001) and the serum levels of HA (p < 0.05), two markers known to prognosticate poor outcome of the osteoarthritis disease process. Nimesulide also reduced the serum levels of both MMP-3 (p < 0.05) and MMP-13 (p < 0.001). Furthermore, in the nimesulide group, the decrease in levels of CTX-II correlated significantly with the decrease in levels of HA and MMP-13.

CONCLUSION

Although nonsteroidal anti-inflammatory drugs are effective in improving pain and disability in OA patients, to date it has been unclear to what extent these drugs could affect joint metabolism and hence joint structure. Patients with flare-up of their osteoarthritis disease process exhibit enhanced levels of markers of joint inflammation and cartilage collagen breakdown, which were markedly decreased by nimesulide but not by ibuprofen.

Cyclooxygenase Isozymes: The Biology of Prostaglandin Synthesis and Inhibition

Nonsteroidal anti-inflammatory drugs (NSAIDs) represent one of the most highly utilized classes of pharmaceutical agents in medicine. All NSAIDs act through inhibiting prostaglandin synthesis, a catalytic activity possessed by two distinct cyclooxygenase (COX) isozymes encoded by separate genes. The discovery of COX-2 launched a new era in NSAID pharmacology, resulting in the synthesis, marketing, and widespread use of COX-2 selective drugs. These pharmaceutical agents have quickly become established as important therapeutic medications with potentially fewer side effects than traditional NSAIDs. Additionally, characterization of the two COX isozymes is allowing the discrimination of the roles each play in physiological processes such as homeostatic maintenance of the gastrointestinal tract, renal function, blood clotting, embryonic implantation, parturition, pain, and fever. Of particular importance has been the investigation of COX-1 and -2 isozymic functions in cancer, dysregulation of inflammation, and Alzheimer's disease. More recently, additional heterogeneity in COX-related proteins has been described, with the finding of variants of COX-1 and COX-2 enzymes. These variants may function in tissue-specific physiological and pathophysiological processes and may represent important new targets for drug therapy.

Matrix metalloproteinases and atherosclerotic plaque instability

BACKGROUND

There is growing interest in the role of matrix metalloproteinases in atherosclerosis. Excessive tissue remodelling and increased matrix metalloproteinase activity have been demonstrated during atherosclerotic plaque disruption, a frequent predeterminant of ischaemic cardiac events and stroke. These enzymes represent a potential target for therapeutic intervention to modify vascular pathology.

METHODS

The core of this review is derived from a Medline database literature search.

RESULTS

There is convincing evidence of increased matrix metalloproteinase activity during acute plaque disruption. Evidence for an imbalance promoting increased matrix degradation is less well documented. However, studies of matrix metalloproteinase inhibition in models of vascular disease suggest a potential therapeutic benefit.

CONCLUSION

In vivo studies of matrix metalloproteinase inhibition are required to study the potential for reversal or deceleration of the excessive tissue remodelling that accompanies acute plaque disruption.

The role of matrix metalloproteinases in vascular disease

There is growing interest in the role of matrix metalloproteinases in vascular diseases. These conditions are often characterized by excessive tissue remodelling, and increased matrix metalloproteinase activity has been demonstrated in aneurysms, intimal hyperplasia and atherosclerotic plaque disruption. These enzymes represent a potential target for therapeutic intervention to modify vascular pathology. The core of this review is derived from a MEDLINE database literature search. The review found that there is convincing evidence of increased matrix metalloproteinase activity in a spectrum of vascular disease. Evidence for an imbalance promoting increased matrix degradation is less well documented. However, studies of matrix metalloproteinase inhibition in vascular disease models suggest potential therapeutic benefit. In conclusion, in vivo studies of matrix metalloproteinase inhibition are required to further study the potential for reversal or deceleration of the excessive tissue remodelling that accompanies vascular disorders.

COX-2 inhibitors compared and contrasted

Non-steroidal anti-inflammatory drugs (NSAIDs) are the principal drug treatments for inflammation, pain and fever. They act primarily by inhibiting prostaglandin (PG) synthesis but this can cause adverse events (AEs). Since the discovery of two PG synthesising enzymes, COX-1 and COX-2, and the substantial evidence that sparing COX-1 is advantageous for gastric safety, great interest has focused on selective COX-2 inhibitors. Much of the impetus has come from the most recently developed compounds celecoxib and rofecoxib, which have shown spectacular sales growth. However, the older drugs etodolac, nimesulide and meloxicam, made before COX-2 was discovered, are also COX-1-sparing and have good GI safety and therapeutic activities. These five compounds show similarities and differences that are discussed in relation to aspects that include their uses, efficacy, actions and safety.

Effects of diclofenac, aceclofenac and meloxicam on the metabolism of proteoglycans and hyaluronan in osteoarthritic human cartilage

1. Since nonsteroidal anti-inflammatory drugs (NSAIDs) may impair the ability of the chondrocyte to repair its damaged extracellular matrix, we explored the changes in the metabolism of newly synthesized proteoglycan and hyaluronan (HA) molecules produced by aceclofenac, diclofenac and meloxicam in human osteoarthritic (OA) cartilage. 2. Explants were sampled from the medial femoral condyle and were classified by use of the Mankin's histological-histochemical grading system. Cartilage specimens exhibited moderate (M) OA in 20 subjects and had severe (S) OA in 20. 3. Cartilage explants were pulsed with [-3H]-glucosamine and chased in the absence or in the presence of 0.3 - 3 microg ml(-1) of either aceclofenac, diclofenac or meloxicam. After papain digestion, the labelled chondroitin sulphate ([-3H]-proteoglycans) and [-3H]-HA molecules present in the tissue and media were purified by anion-exchange chromatography. 4. In cartilage with MOA and SOA, the metabolic balance of proteoglycan and HA was unaffected by diclofenac. In contrast, and in a dose-dependent manner, aceclofenac and meloxicam both increased the synthesis of proteoglycans and HA in explants with MOA and SOA; these two NSAIDs also reduced significantly the net loss of [-3H]-proteoglycans and [-3H]-HA molecules from cartilage explants. 5. The data obtained in short-term in vitro cultures indicate that, at the concentrations found in synovial fluid, aceclofenac and meloxicam may exert a favourable effect on the overall metabolism of proteoglycans and HA in cartilage with MOA and SOA.

Profile and mechanisms of gastrointestinal and other side effects of nonsteroidal anti-inflammatory drugs (NSAIDs)

The popular view that all nonsteroidal anti-inflammatory drugs (NSAIDs) act by inhibiting the production of prostaglandins has been challenged by the discovery that they also affect a wide variety of cellular processes that are important for their therapeutic actions and side effects. Although recognition of the differential activities of new and established NSAIDs on the activities of the cyclooxygenases (COXs) affecting production of inflammatory prostaglandins (from COX-2) and those that are physiologically important (from COX-1) may have significance for the prostaglandin components of the underlying inflammatory and physiologic processes, there are important features of their chemical structures that determine the various cellular and biochemical actions of these agents. Several established NSAIDs have low propensity to cause gastrointestinal (GI) ulceration and bleeding that may relate to these drugs having unique pharmacokinetic characteristics (pro-drugs, protein binding, etc). They also have weak effects on the production of GI mucosal prostaglandins and have specific physicochemical characteristics such that they cause minimal damage to mucosal membranes or effects on nonprostaglandin-related cellular mechanisms important in mucosal defenses. Some of the new COX-2-selective drugs with methyl or amino-sulfonyl moieties have relatively high pKa values and other properties that are similar to established NSAIDs with low GI ulcerogenicity. These physicochemical properties may contribute to the low irritancy of the new COX-2-selective drugs quite apart from their sparing of COX-1 in the GI mucosa. With concerns that some established NSAIDs may accelerate cartilage destruction in osteoarthritis (OA), interest is now focusing on whether the COX-2-selective drugs may have a lower potential for this adverse effect by avoiding the inhibitory effects on cartilage proteoglycan metabolism seen with such drugs as indomethacin and the salicylates. Meloxicam appears to be without inhibitory effects on proteoglycan metabolism, but it remains to be seen if this translates into any beneficial actions on the progression of joint changes in OA observed radiologically or from magnetic resonance imaging.