Matrix metalloproteinases in metabolic syndrome

Association between metabolic syndrome and salivary MMP-8, myeloperoxidase in periodontitis

OBJECTIVE

This study investigated the effect of metabolic syndrome (MetS) on periodontal clinical parameters and salivary biomarkers' matrix metalloproteinase-8 (MMP-8) and myeloperoxidase (MPO) in patients with periodontitis.

METHODS

A total of 120 participants aged 25-55 were categorized into three groups: MetS with periodontitis (n = 40); systemically healthy with periodontitis (n = 40); and systemically and periodontally healthy controls (n = 40). Data collected included systemic parameters like waist circumference (WC), blood pressure (BP), high- and low-density lipoproteins, triglycerides (TG), fasting blood sugar (FBS), and glycated hemoglobin (HbA1c). Periodontal parameters estimated included bleeding on probing score (BoP), full-mouth plaque score (FMPS), periodontal probing depth (PPD), clinical attachment loss (CAL), and the number of missing teeth. Unstimulated whole saliva was analyzed via ELISA for active MMP-8 (aMMP-8), total MMP-8 (tMMP-8), and MPO.

RESULTS

Participants with MetS and periodontitis exhibited significantly higher periodontal parameters, salivary aMMP-8, and MPO (26.26 vs. 24.1 ng/mL and 13.53 vs. 11.55 ng/mL compared to systemically healthy periodontitis patients) (all p < 0.01). Positive correlations occurred between aMMP-8 and WC, TG, and FBS (p < 0.01), and between MPO and WC, BP, and TG (p < 0.01).

CONCLUSIONS

The positive associations between these biomarkers and metabolic parameters indicate their potential utility for monitoring cardiovascular and glycemic risk in patients with periodontal disease.

Neuraminidase-1 (NEU1): Biological Roles and Therapeutic Relevance in Human Disease

Neuraminidases catalyze the desialylation of cell-surface glycoconjugates and play crucial roles in the development and function of tissues and organs. In both physiological and pathophysiological contexts, neuraminidases mediate diverse biological activities via the catalytic hydrolysis of terminal neuraminic, or sialic acid residues in glycolipid and glycoprotein substrates. The selective modulation of neuraminidase activity constitutes a promising strategy for treating a broad spectrum of human pathologies, including sialidosis and galactosialidosis, neurodegenerative disorders, cancer, cardiovascular diseases, diabetes, and pulmonary disorders. Structurally distinct as a large family of mammalian proteins, neuraminidases (NEU1 through NEU4) possess dissimilar yet overlapping profiles of tissue expression, cellular/subcellular localization, and substrate specificity. NEU1 is well characterized for its lysosomal catabolic functions, with ubiquitous and abundant expression across such tissues as the kidney, pancreas, skeletal muscle, liver, lungs, placenta, and brain. NEU1 also exhibits a broad substrate range on the cell surface, where it plays hitherto underappreciated roles in modulating the structure and function of cellular receptors, providing a basis for it to be a potential drug target in various human diseases. This review seeks to summarize the recent progress in the research on NEU1-associated diseases and highlight the mechanistic implications of NEU1 in disease pathogenesis. An improved understanding of NEU1-associated diseases should help accelerate translational initiatives to develop novel or better therapeutics.

Inflammatory protein signatures in individuals with obesity and metabolic syndrome

There is variability in the metabolic health status among individuals presenting with obesity; some may be metabolically healthy, while others may have developed the metabolic syndrome, a cluster including insulin resistance, hypertension, dyslipidemia, and increased risk of cardiovascular disease and type 2 diabetes. The mechanisms contributing to this metabolic heterogeneity are not fully understood. To address this question, plasma samples from 48 individuals with BMI ≥ 35 kg/m2 were examined (27 with and 21 without metabolic syndrome). Fasting plasma samples were subjected to Olink proteomics analysis for 184 cardiometabolic and inflammation-enriched proteins. Data analysis showed a clear differentiation between the two groups with distinct plasma protein expression profiles. Twenty-four proteins were differentially expressed (DEPs) between the two groups. Pathways related to immune cell migration, leukocyte chemotaxis, chemokine signaling, mucosal inflammatory response, tissue repair and remodeling were enriched in the group with metabolic syndrome. Functional analysis of DEPs revealed upregulation of 15 immunological pathways. The study identifies some of the pathways that are altered and reflect metabolic health in individuals with obesity. This provides valuable insights into some of the underlying mechanisms and can lead to identification of therapeutic targets to improve metabolic health in individuals with obesity.

A Green Bioactive By-Product Almond Skin Functional Extract for Developing Nutraceutical Formulations with Potential Antimetabolic Activity

(1) Background: almond peels are rich in polyphenols such as catechin and epicatechin, which are important anti-free-radical agents, anti-inflammatory compounds, and capable of breaking down cholesterol plaques. This work aims to evaluate the biological and technological activity of a "green" dry aqueous extract from Sicilian almond peels, a waste product of the food industry, and to develop healthy nutraceuticals with natural ingredients. Eudraguard® Natural is a natural coating polymer chosen to develop atomized formulations that improve the technological properties of the extract. (2) Methods: the antioxidant and free radical scavenger activity of the extract was rated using different methods (DPPH assay, ABTS, ORAC, NO). The metalloproteinases of the extracts (MMP-2 and MMP-9), the enhanced inhibition of the final glycation products, and the effects of the compounds on cell viability were also tested. All pure materials and formulations were characterized using UV, HPLC, FTIR, DSC, and SEM methods. (3) Results: almond peel extract showed appreciable antioxidant and free radical activity with a stronger NO inhibition effect, strong activity on MMP-2, and good antiglycative effects. In light of this, a food supplement with added health value was formulated. Eudraguard® Natural acted as a swelling substrate by improving extract solubility and dissolution/release (4) Conclusions: almond peel extract has significant antioxidant activity and MMP/AGE inhibition effects, resulting in an optimal candidate to formulate safe microsystems with potential antimetabolic activity. Eudraguard® Natural is capable of obtaining spray-dried microsystems with an improvement in the extract's biological and technological characteristics. It also protects the dry extract from degradation and oxidation, prolonging the shelf life of the final product.

Soluble ST2 as a New Oxidative Stress and Inflammation Marker in Metabolic Syndrome

BACKGROUND

Metabolic syndrome (MS) is a complex and prevalent disorder. Oxidative stress and inflammation might contribute to the progression of MS. Soluble ST2 (sST2) is an attractive and druggable molecule that sits at the interface between inflammation, oxidative stress and fibrosis. This study aims to analyze the relationship among sST2, oxidative stress, inflammation and echocardiographic parameters in MS patients.

METHODS

Fifty-eight patients with MS were recruited and underwent physical, laboratory and transthoracic echocardiography examinations. Commercial ELISA and appropriate colorimetric assays were used to quantify serum levels of oxidative stress and inflammation markers and sST2.

RESULTS

Circulating sST2 was increased in MS patients and was significantly correlated with the oxidative stress markers nitrotyrosine and 8-hydroxy-2'-deoxyguanosine as well as with peroxide levels. The inflammatory parameters interleukin-6, intercellular adhesion molecule-1 and myeloperoxidase were positively correlated with sST2. Noteworthy, sST2 was positively correlated with left ventricular mass, filling pressures and pulmonary arterial pressures.

CONCLUSION

Circulating levels of sST2 are associated with oxidative stress and inflammation burden and may underlie the pathological remodeling and dysfunction of the heart in MS patients. Our results suggest that sST2 elevation precedes diastolic dysfunction, emerging as an attractive biotarget in MS.

Among biomarkers of neutrophil activity, matrix metalloproteinases 8 independently predicts remission of metabolic syndrome

BACKGROUND AND AIMS

Inflammation due to the excess of nutrient intake plays an important role in the pathophysiology of metabolic syndrome (MetS). Here, the potential influence of neutrophils and their degranulation markers on MetS improvement upon dietary and behavioral counselling, has been investigated. Specifically, we aimed at investigating their role as potential predictors of metabolic syndrome improvements.

METHODS AND RESULTS

patients with MetS (n = 127) received behavioral and dietary recommendations before follow-up at 6 months. Serum levels of matrix metalloproteinases (MMP)8, MMP9, myeloperoxidase (MPO), tissue inhibitor of MMP (TIMP)-1, TIMP-2, TIMP-3 and resistin were tested at baseline. In the whole cohort, baseline levels of proinflammatory MMP8, MMP9 and MPO increased together with the number of MetS criteria. Seventy-three (57%) patients experienced a reduction in MetS-defining criteria at follow-up. With respect to those with no improvement, such individuals showed lower weight and waist circumference at enrolment, less frequent smoking habits, higher levels of triglycerides and lower circulating MMP8. At logistic regression analysis, baseline MMP8 showed negative predictive ability (odds ratio (OR) 0.979 [0.961-0.997]; p = 0.025) against MetS improvement. Such findings hold true even when included in the backward stepwise logistic regression model confirming MMP8 as an independent predictor (OR 0.970 [0.949-0.993]; p = 0.009). Receiver operating characteristic (ROC) curve confirmed the predictive ability of MMP8 combined in a model including baseline MetS criteria and waist circumference. Bootstrap resampling analysis internally validated our findings.

CONCLUSION

Improvement of MetS is independently associated with baseline low MMP-8 levels, suggesting a pivotal role for inflammation in metabolic alteration.

The Predictive Values of MMP-9, PLTs, ESR, and CRP Levels in Kawasaki Disease with Cardiovascular Injury

Objective

To explore the levels of matrix metalloproteinase-9 (MMP-9), platelets (PLTs), C reactive protein (CRP), and erythrocyte sedimentation rate (ESR) and their predictive values in Kawasaki disease (KD) with cardiovascular injury.

Methods

128 children were diagnosed with KD in the Lanzhou University Second Hospital. 75 patients had coronary artery lesion (CAL), while 53 patients did not. The levels of MMP-9, PLTs, and CRP and ESR in the two groups were determined. The area under the curve (AUC) of the receiver-operating characteristic (ROC) curve and the Youden index (YI) were used to evaluate the efficacy of MMP-9, PLTs, ESR, and CRP for predicting CALs in KD.

Results

The mean age of the patients was 2.7 ± 2.03 years (range, 2 months to 11 years). There were 87 boys (67.97%) and 41 girls (32.03%). In contrast to the NCAL group, the CAL group had obviously higher levels of MMP-9, PLTs, and CRP and an obviously higher ESR (P < 0.05). MMP-9 showed a linear positive correlation with ESR (P < 0.05) and CRP (P < 0.05). The AUC of the combined detection of the four indicators was 0.877, the sensitivity was 85.07% and the specificity was 78.95%.

Conclusion

MMP-9, PLTs, ESR, and CRP are important indicators for a CAL in KD. The efficacy of the combined detection of MMP-9, PLTs, ESR and CRP is better than that of any single indicator for predicting a CAL in KD.

Bimodal Effects of P2Y12 Antagonism on Matrix Metalloproteinase-Associated Contractile Dysfunction in İnsulin-Resistant Mammalian Heart

The matrix metalloproteinases (MMPs) contribute to matrix remodeling in diabetes via tissue degradation; however, their contributions can be different depending on the pathology. For instance, MMPs are elevated in acute stress hyperglycemia, whereas they can be degraded in chronic hyperglycemia. Since studies emphasize the possible cardioprotective effect of ticagrelor (Tica) beyond its antiplatelet action, we aimed to examine whether Tica treatment can reverse the depressed heart function of metabolic syndrome (MetS) rats via affecting the expression levels of MMPs. Tica treatment of high-carbohydrate-induced MetS rats could not affect significantly the depressed contractile activity of Langendorff-perfused heart preparations. On the other hand, the Tica treatment provided a significant recovery in the reduced relaxation activity of the aortic preparations from the same animals. Histological examination of the hearts demonstrated marked damages in Mets rats, such as increases in the number of foamy cells and accumulation of collagen fiber and increases in the elastic lamellar irregularity of tunica media, while Tica treatment provided a slight improvement in the structure of left ventricle tissue. We also could not obtain a significant reverse in the high cytosolic labile Zn²⁺ ([Zn²⁺]_i) with the treatment of cardiomyocytes with Tica. Furthermore, Tica treatment of MetS rats could not significantly reverse the degraded protein levels of MMP-2 and MMP-9 in the heart, as well. Overall, we demonstrated that Tica treatment of MetS rats has no significant benefits on the depressed heart function, although provide a significant beneficial impact on vascular relaxation. This action of Tica may be through its lack of action on both MMP degradation and high [Zn²⁺]_i, which can further precipitate in cleavage of extracellular matrix in the heart.

Human Neuraminidases: Structures and Stereoselective Inhibitors

This Perspective describes the classification, structures, substrates, mechanisms of action, and implications of human neuraminidases (hNEUs) in various pathologies. Some inhibitors have been developed for each isoform, leading to more precise interactions with hNEUs. Although crystal structure data are available for NEU2, most of the findings are based on NEU1 inhibition, and limited information is available for other hNEUs. Therefore, the synthesis of new compounds would facilitate the enrichment of the arsenal of inhibitors to better understand the roles of hNEUs and their mechanisms of action. Nevertheless, due to the already known inhibitors of human neuraminidase enzymes, a structure-activity relationship is presented along with different approaches to inhibit these enzymes for the development of potent and selective inhibitors. Among the different emerging strategies, one is the inhibition of the dimerization of NEU1 or NEU3, and the second is the inhibition of certain receptors located close to hNEU.

Mechanisms and Active Compounds Polysaccharides and Bibenzyls of Medicinal Dendrobiums for Diabetes Management

BACKGROUND

Medicinal dendrobiums are used popularly in traditional Chinese medicine for the treatment of diabetes, while their active compounds and mechanism remain unclear. This review aimed to evaluate the mechanism and active compounds of medicinal dendrobiums in diabetes management through a systematic approach.

METHODS

A systematic approach was conducted to search for the mechanism and active phytochemicals in Dendrobium responsible for anti-diabetic actions using databases PubMed, Embase, and SciFinder.

RESULTS

Current literature indicates polysaccharides, bibenzyls, phenanthrene, and alkaloids are commonly isolated in Dendrobium genusin which polysaccharides and bibenzyls are most aboundant. Many animal studies have shown that polysaccharides from the species of Dendrobium provide with antidiabetic effects by lowering glucose level and reversing chronic inflammation of T2DM taken orally at 200 mg/kg. Dendrobium polysaccharides protect pancreatic β-cell dysfunction and insulin resistance in liver. Dendrobium polysaccharides up-regulate the abundance of short-chain fatty acid to stimulate GLP-1 secretion through gut microbiota. Bibenzyls also have great potency to inhibit the progression of the chronic inflammation in cellular studies.

CONCLUSION

Polysaccharides and bibenzyls are the major active compounds in medicinal dendrobiums for diabetic management through the mechanisms of lowering glucose level and reversing chronic inflammation of T2DM by modulating pancreatic β-cell dysfunction and insulin resistance in liver as a result from gut microbita regulation.

MMPs and TIMPs levels are correlated with anthropometric parameters, blood pressure, and endothelial function in obesity

The association between matrix metalloproteinases (MMPs), tissue inhibitor of metalloproteinases (TIMPs) and obesity as well as obesity-related disease including metabolic syndrome is not fully explored. Our aims are that: (i) to evaluate the plasma levels of MMP-1, MMP-2, MMP-3, MMP-9, TIMP-1, TIMP-2 and their ratios in non-obese people, overweight and obese people with or without metabolic syndrome, (ii) to investigate correlations between MMPs or TIMPs levels and several anthropometric parameters, blood pressure, endothelial function. Anthropometric and biochemical parameters were determined in 479 randomly selected participants, subdividing according to body mass index (BMI) and metabolic syndrome status. Plasma MMPs and TIMPs levels were measured. The assessment of endothelial function was characterized in people with obesity, overweight and non-obese, using laser Doppler Flowmetry. Obese people have elevated MMP-1, MMP-2, TIMP-1, TIMP-2 levels and decreased MMP-3/TIMP-1 and MMP-9/TIMP-1 ratios compared with non-obese people. MMP-1 levels and MMP-1/TIMP-1 ratio were positively correlated with BMI and waist circumference (WC) while MMP-2 levels were negatively correlated with BMI and WC values in obese people. MMP-3 levels and MMP-3/TIMP-1 ratio were positively correlated with systolic blood pressure (SBP) or diastolic blood pressure (DBP) in obese and metabolic syndrome people. Additionally, MMP-9 levels and MMP-9/TIMP-1 ratio were negatively correlated with endothelium-dependent response in obese and metabolic syndrome people. MMP-1, MMP-2, TIMP-1, TIMP-2 levels were increased in obese subjects. Significant correlations between anthropometric parameters and MMP-1 as well as MMP-1/TIMP-1 ratio supported these results. MMP-3 and -9 levels as well as their ratios with TIMP-1 were associated with blood pressure and endothelial-dependent response, respectively. In conclusion, our results demonstrated that MMP-1, MMP-3 and MMP-9 levels were correlated with several obesity-related parameters including BMI, WC, blood pressure and endothelial-dependent response. Our findings will hopefully provide new aspects for the use of MMPs and TIMPs as clinical biomarkers in obesity-related cardiovascular diseases such as metabolic syndrome and hypertension. The lack of measure of MMPs activity in plasma and relevant organs/tissues in obesity and metabolic syndrome is considered as a limitation in this report.

Vitamin D Levels Correlate with Metabolic Syndrome Criteria in Algerian Patients: The Ex-vivo Immunomodulatory Effect of α, 25 Dihydroxyvitamin D3

BACKGROUND

Metabolic syndrome (MetS) is a combination of metabolic disorders with increased risks for several diseases, such as cardiovascular diseases and diabetes. It is associated with the presence of various inflammatory molecules. Vitamin D plays an important role in the regulation of metabolism homeostasis.

OBJECTIVE

The main goal of this work is to investigate vitamin D levels among Algerian MetS patients and its possible outcomes on key molecules of the immune response, as well, the immunomodulatory effects of its active metabolite.

METHODS

We evaluated vitamin D status by the electrochemiluminescence method, Nitric Oxide (NO) levels by the Griess method and Matrix Metalloproteinases (MMPs) activities such as MMP-2 and MMP-9 by zymography in plasma of patients and healthy controls (HC). The immunomodulatory effects of the active metabolite of vitamin D (α-25 (OH)2D3) on the production of NO, IL-6, IL-10, TGF- β and s-CTLA-4 were assessed by Griess method and ELISA, in peripheral blood mononuclear cells (PBMCs) of Algerian MetS patients and HC. MMPs activities were also determined ex-vivo, while iNOS expression was assessed by immunofluorescence staining.

RESULTS

Severe vitamin D deficiency was registered in Algerian MetS patients. The deficiency was found to be associated with an elevated in vivo NO production and high MMPs activity. Interestingly, α-25 (OH)2D3 declined the NO/iNOS system and IL-6 production, as well as MMPs activities. However, the ex-vivo production of IL-10, TGF-β increased in response to the treatment. We observed in the same way, the implication of s-CTLA-4 in MetS, which was markedly up-regulated with α-25 (OH)2D3.

CONCLUSION

Our report indicated the relationship between MetS factors and Vitamin D deficiency. The ex-vivo findings emphasize its impact on maintaining regulated immune balance.

Pathophysiological adaptations of resistance arteries in rat offspring exposed in utero to maternal obesity is associated with sex-specific epigenetic alterations

BACKGROUND/OBJECTIVES

Maternal obesity impacts vascular functions linked to metabolic disorders in offspring, leading to cardiovascular diseases during adulthood. Even if the relation between prenatal conditioning of cardiovascular diseases by maternal obesity and vascular function begins to be documented, little is known about resistance arteries. They are of particular interest because of their specific role in the regulation of local blood flow. Then our study aims to determine if maternal obesity can directly program fetal vascular dysfunction of resistance arteries, independently of metabolic disorders.

METHODS

With a model of rats exposed in utero to mild maternal diet-induced obesity (OMO), we investigated third-order mesenteric arteries of 4-month old rats in absence of metabolic disorders. The methylation profile of these vessels was determined by reduced representation bisulfite sequencing (RRBS). Vascular structure and reactivity were investigated using histomorphometry analysis and wire-myography. The metabolic function was evaluated by insulin and glucose tolerance tests, plasma lipid profile, and adipose tissue analysis.

RESULTS

At 4 months of age, small mesenteric arteries of OMO presented specific epigenetic modulations of matrix metalloproteinases (MMPs), collagens, and potassium channels genes in association with an outward remodeling and perturbations in the endothelium-dependent vasodilation pathways (greater contribution of EDHFs pathway in OMO males compared to control rats, and greater implication of PGI₂ in OMO females compared to control rats). These vascular modifications were detected in absence of metabolic disorders.

CONCLUSIONS

Our study reports a specific methylation profile of resistance arteries associated with vascular remodeling and vasodilation balance perturbations in offspring exposed in utero to maternal obesity, in absence of metabolic dysfunctions.

A multitarget angiogenesis inhibitor, CTT peptide-endostatin mimic-kringle 5, prevents diet-induced obesity

Adipose tissue vasculature has been considered an attractive target for prevention and treatment of obesity. AARP (CTT peptide-endostatin mimic-kringle 5) is a novel multitarget fusion protein against tumor angiogenesis. This study aimed to examine the effects of AARP on diet-induced obesity and its possible molecular mechanism. Treatment with AARP markedly prevented weight gains, improved metabolic disturbances, and decreased adipose tissue angiogenesis in diet-induced obese mice without noticeable toxicities. In addition to its potent antiangiogenic and MMP-2/9 inhibitory activities, AARP administration also significantly increased energy expenditure, influenced the metabolic and angiogenic gene expression profiles, and attenuated obesity-induced inflammation, demonstrating its systemic beneficial effects. Importantly, AARP exhibited no effect on mice fed with standard normal mouse diet. Furthermore, the AARP-treated HFD-fed mice experienced a significant increase in lifespan during the posttreatment observation period, compared with untreated HFD-fed mice. Our results suggest that AARP might be pharmacologically useful for treatment of obesity or obesity-related metabolic disorders in humans. KEY MESSAGES: What is already known • More effective and safe therapies for obesity are in urgent need. • AARP is a novel multitarget fusion protein against tumor angiogenesis. What this study adds • AARP prevents obesity, improves metabolic disorders in mice fed high-fat diet. • AARP increases energy expenditure, decreases adipose tissue angiogenesis, and increases lifespan. • AARP is well tolerated and exhibits no observable toxicity. Clinical significance • AARP may be a promising therapeutic agent against obesity or obesity-related metabolic disturbances.

The interaction between dietary inflammatory index and 6 P21 rs2010963 gene variants in metabolic syndrome

BACKGROUND

The Vascular endothelial growth factor (VEGF) regulates endothelial cell proliferation, migration and angiogenesis, promotes vascular and capillary permeability and also is involved in inflammation. VEGF gene has been suggested to play an important role in the pathogenesis of metabolic syndrome. The aim of this study was to investigate the association between inflammatory potential of a diet and + 405 VEGF C/G (rs2010963) polymorphism and metabolic components in patients with metabolic syndrome.

METHODS

One hundred fifty patients with metabolic syndrome and fifty healthy individuals were enrolled. A semi-quantitative food-frequency questionnaire (FFQ) was used for dietary assessments and dietary inflammatory index (DII) calculation. Biochemical assays including fasting serum glucose (FSG), serum insulin, matrix metalloproteinase-3 (MMP-3), liver enzymes and lipid profile were measured. Polymerase chain reaction-restriction fragments length polymorphism (PCR-RFLP) method was used for the determination of gene polymorphism.

RESULTS

In the current study, patients with metabolic syndrome had higher serum low density lipoprotein (LDL) and lower high density lipoprotein (HDL) concentrations compared with healthy subjects. Patients with lower DII quartiles and lower inflammatory potential of the diet had lower waist to hip ratio (WHR) and lower diastolic blood pressure (DBP) compared with patients in higher DII quartiles (P < 0.05). Moreover, patients and healthy subjects in second quartile of DII had significantly higher aspartate aminotransferase (AST) and alanine aminotransferase (ALT) concentrations compared with subjects in the first quartile; also healthy subjects in third quartile had significantly higher triglyceride (TG) and total cholesterol (TC) concentrations compared with subjects in second quartile (P < 0.05). Among different genotypes of 6 P21 rs2010963 gene variants in patients with metabolic syndrome, CC genotype indicated the highest DII compared with other genotypes (P < 0.05).

CONCLUSION

The current study revealed the association between DII and metabolic risk factors of metabolic syndrome.

LEVEL OF EVIDENCE

Level III, case-control analytic study.

Dietary natural products as epigenetic modifiers in aging-associated inflammation and disease

Covering: up to 2020Chronic, low-grade inflammation is linked to aging and has been termed "inflammaging". Inflammaging is considered a key contributor to the development of metabolic dysfunction and a broad spectrum of diseases or disorders including declines in brain and heart function. Genome-wide association studies (GWAS) coupled with epigenome-wide association studies (EWAS) have shown the importance of diet in the development of chronic and age-related diseases. Moreover, dietary interventions e.g. caloric restriction can attenuate inflammation to delay and/or prevent these diseases. Common themes in these studies entail the use of phytochemicals (plant-derived compounds) or the production of short chain fatty acids (SCFAs) as epigenetic modifiers of DNA and histone proteins. Epigenetic modifications are dynamically regulated and as such, serve as potential therapeutic targets for the treatment or prevention of age-related disease. In this review, we will focus on the role for natural products that include phytochemicals and short chain fatty acids (SCFAs) as regulators of these epigenetic adaptations. Specifically, we discuss regulators of methylation, acetylation and acylation, in the protection from chronic inflammation driven metabolic dysfunction and deterioration of neurocognitive and cardiac function.

Effect of a Very-Low-Calorie Ketogenic Diet on Circulating Myokine Levels Compared with the Effect of Bariatric Surgery or a Low-Calorie Diet in Patients with Obesity

: The preservation of muscle mass and muscle function after weight loss therapy is currently a considerable challenge in the fight against obesity. Muscle mass secretes proteins called myokines that have relevant functions in the regulation of metabolism and health. This study was aimed to evaluate whether a very low-calorie ketogenic (VLCK) diet may modulate myokine levels, in addition to changes in body composition, compared to a standard, balanced low-calorie (LC) diet or bariatric surgery in patients with obesity. Body composition, ketosis, insulin sensitivity and myokines were evaluated in 79 patients with overweight/obesity after a therapy to lose weight with a VLCK diet, a LC diet or bariatric surgery. The follow-up was 6 months. The weight loss therapies induced changes in myokine levels in association with changes in body composition and biochemical parameters. The effects on circulating myokine levels compared to those at baseline were stronger after the VLCK diet than LC diet or bariatric surgery. Differences reached statistical significance for IL-8, MMP2 and irisin. In conclusion, nutritional interventions or bariatric surgery to lose weight induces changes in circulating myokine levels, being this effect potentially most notable after following a VLCK diet.

Persistent Salmonella enterica Serovar Typhimurium Infection Induces Protease Expression During Intestinal Fibrosis

BACKGROUND

Intestinal fibrosis is a common and serious complication of Crohn's disease characterized by the accumulation of fibroblasts, deposition of extracellular matrix, and formation of scar tissue. Although many factors including cytokines and proteases contribute to the development of intestinal fibrosis, the initiating mechanisms and the complex interplay between these factors remain unclear.

METHODS

Chronic infection of mice with Salmonella enterica serovar Typhimurium was used to induce intestinal fibrosis. A murine protease-specific CLIP-CHIP microarray analysis was employed to assess regulation of proteases and protease inhibitors. To confirm up- or downregulation during fibrosis, we performed quantitative real-time polymerase chain reaction (PCR) and immunohistochemical stainings in mouse tissue and tissue from patients with inflammatory bowel disease. In vitro infections were used to demonstrate a direct effect of bacterial infection in the regulation of proteases.

RESULTS

Mice develop severe and persistent intestinal fibrosis upon chronic infection with Salmonella enterica serovar Typhimurium, mimicking the pathology of human disease. Microarray analyses revealed 56 up- and 40 downregulated proteases and protease inhibitors in fibrotic cecal tissue. Various matrix metalloproteases, serine proteases, cysteine proteases, and protease inhibitors were regulated in the fibrotic tissue, 22 of which were confirmed by quantitative real-time PCR. Proteases demonstrated site-specific staining patterns in intestinal fibrotic tissue from mice and in tissue from human inflammatory bowel disease patients. Finally, we show in vitro that Salmonella infection directly induces protease expression in macrophages and epithelial cells but not in fibroblasts.

CONCLUSIONS

In summary, we show that chronic Salmonella infection regulates proteases and protease inhibitors during tissue fibrosis in vivo and in vitro, and therefore this model is well suited to investigating the role of proteases in intestinal fibrosis.

Matrix metalloproteinases as possible biomarkers of obstructive sleep apnea severity - A systematic review

Obstructive sleep apnea is an underdiagnosed sleep-related breathing disorder affecting millions of people. Recurrent episodes of apnea/hypopnea result in intermittent hypoxia leading to oxidative stress. Obstructive sleep apnea is considered an independent risk factor for cardiovascular disease but the exact pathophysiology of adverse cardiovascular outcomes of obstructive sleep apnea has not been fully elucidated. Matrix metalloproteinases (MMPs) have been associated with both oxidative stress and cardiovascular diseases. Hypoxic conditions were shown to influence MMP expression, secretion and activity. Moreover, matrix metalloproteinases contribute to ischemia/reperfusion injury. Therefore, action of matrix metalloproteinases can provide a possible molecular mechanism linking obstructive sleep apnea with oxidative stress and cardiovascular disease. The aim of this paper was to review the current evidence of association between matrix metalloproteinases and obstructive sleep apnea with focus on hypoxemia and severity of obstructive sleep apnea.

Characterization of thoracal fat depots - expression of adipokines and remodeling factors and impact of adipocyte conditioned media in fibroblast scratch assays

Adipose tissue is not only a connective tissue but also an endocrine organ secreting adipokines like Leptin and Adiponectin, lipokines such as palmitoileic acid and extracellular vesicles. These factors and the expression of matrix remodeling enzymes impact surrounding tissues via paracrine effects. The expression of selected secretion factors and the effect of adipocyte conditioned media from four thoracal adipose tissue origins - subcutaneous, perivascular, pericardial and epicardial adipose tissues - in a fibroblast proliferation/wound healing scratch assay model were investigated. Results were compared directly and according to the type 2 diabetic mellitus (T2DM) status of the patients the tissues are originated from. Adipocyte conditioned media from non-diabetic patients resulted in a significant higher scratch closure rate compared to the media with T2DM background. Linoleic acid incubation in scratch assay resulted in a reduced scratch closure rate. Leptin, Adiponectin and Visfatin/Nampt expression and MMP2, MMP9 and FSTL1 mRNA levels did not vary according to T2DM subgroups directly, leading to the assumption that these factors are not causal for scratch assay effects observed. In contrast significant mRNA expression differences were monitored between the thoracal tissue origins implying variations in the local effects of the different adipose tissue depots.

Association of HIV-infection, antiretroviral treatment and metabolic syndrome with large artery stiffness: a cross-sectional study

Background

Effective combined antiretroviral therapy (cART) has improved life expectancy among people living with HIV-1 infection. Treated HIV-1infection increases the prevalence of metabolic syndrome (MS). Despite sub-Saharan Africa having among the highest rates of HIV-1 infection, the effects of MS in HIV-1-infected individuals on cardiovascular risk is poorly explored. The aim of the study was to assess whether MS and/or HIV-1 treatment correlates with large elastic artery stiffness in HIV-1-infected patients treated with first-line cART.

Methods

The study sample comprised of 102 subjects free of cardiovascular disease and major risk factors divided into two groups based on HIV-1 infection, treatment, and MS status: HIV-1⁺/cART⁺/MS⁺ (n = 12); HIV-1⁺/cART⁻/MS⁺ (n = 16); HIV-1⁻/ MS⁺ (n = 10); HIV-1⁺/cART⁺/MS⁻ (n = 42); HIV-1⁺/cART⁻/MS⁻ (n = 32); HIV-1⁻/ MS⁻ (n = 39). MS was established according the International Diabetes Federation definition. Large artery stiffness was measured using applanation tonometry to assess aortic pulse wave velocity (aPWV) and aortic augmentation index at heart rate of 75 bpm (AIx@HR75). cART included lamivudine/zidovudine and nevirapine or efavirenz.

Results

The prevalence of MS in the HIV-1-infected patients was 28%. There were no significant differences in aPWV in the non-MS groups. However, in subjects with MS, aPWV was significantly higher in the HIV-1 cART patients (9.0 ± 1.9 m/s) compared with both controls (7.5 ± 1.8 m/s; P = 0.018) and untreated HIV-1 patients (7.7 ± 1.3 m/s; P = 0.023), and these differences remained after adjustment for blood pressure and sex. Aortic PWV was significantly elevated (P = 0.009) in HIV-1 cART patients with MS compared to their counterparts without MS. Untreated HIV-1 patients with MS also demonstrated increased aPWV compared to their counterparts without MS (P = 0.05). Aortic AIx@HR75 was, on average, ~ 5% higher in HIV-1 cART patients with MS (28.3 ± 62% compared with untreated HIV-1 patients with MS (23.5 ± 9%; P = 0.075). Sub-group multivariate analysis identified MS as an independent predictor of increased aPWV in HIV-1 cART patients.

Conclusions

Our study established that presence of MS in HIV-1 patients on treatment was associated with increased aPWV and hence increased arterial stiffness in sub-Saharan African HIV-1 patients on first-line cART.

Evaluation of [68Ga]Ga-DOTA-TCTP-1 for the Detection of Metalloproteinase 2/9 Expression in Mouse Atherosclerotic Plaques

Background: The expression of matrix metalloproteinases 2/9 (MMP-2/9) has been implicated in arterial remodeling and inflammation in atherosclerosis. We evaluated a gallium-68 labeled peptide for the detection of MMP-2/9 in atherosclerotic mouse aorta. Methods: We studied sixteen low-density lipoprotein receptor deficient mice (LDLR^-/-ApoB^100/100) kept on a Western-type diet. Distribution of intravenously-injected MMP-2/9-targeting peptide, [⁶⁸Ga]Ga-DOTA-TCTP-1, was studied by combined positron emission tomography (PET) and contrast-enhanced computed tomography (CT). At 60 min post-injection, aortas were cut into cryosections for autoradiography analysis of tracer uptake, histology, and immunohistochemistry. Zymography was used to assess MMP-2/9 activation and pre-treatment with MMP-2/9 inhibitor to assess the specificity of tracer uptake. Results: Tracer uptake was not visible by in vivo PET/CT in the atherosclerotic aorta, but ex vivo autoradiography revealed 1.8 ± 0.34 times higher tracer uptake in atherosclerotic plaques than in normal vessel wall (p = 0.0029). Tracer uptake in plaques correlated strongly with the quantity of Mac-3-positive macrophages (R = 0.91, p < 0.001), but weakly with MMP-9 staining (R = 0.40, p = 0.099). Zymography showed MMP-2 activation in the aorta, and pre-treatment with MMP-2/9 inhibitor decreased tracer uptake by 55% (p = 0.0020). Conclusions: The MMP-2/9-targeting [⁶⁸Ga]Ga-DOTA-TCTP-1 shows specific uptake in inflamed atherosclerotic lesions; however, a low target-to-background ratio precluded in vivo vascular imaging. Our results suggest, that the affinity of gelatinase imaging probes should be steered towards activated MMP-2, to reduce the interference of circulating enzymes on the target visualization in vivo.

A sodium-glucose cotransporter 2 (SGLT2) inhibitor dapagliflozin comparison with insulin shows important effects on Zn2+-transporters in cardiomyocytes from insulin-resistant metabolic syndrome rats through inhibition of oxidative stress 1

Sodium-glucose cotransporter 2 (SGLT2) inhibitors showed significant effects in patients with diabetes or metabolic syndrome (MetS) with high cardiovascular risk. Although the increased intracellular Zn²⁺ level ([Zn²⁺]_i), oxidative stress, and altered cardiac matrix metalloproteinases (MMPs) in diabetic cardiomyopathy can intersect with different signaling pathways, the exact mechanisms are not known yet. Since either MMPs or SGLT2 have important roles in cardiac-fibrosis under hyperglycemia, we aimed to examine the role of SGLT2 inhibitor dapagliflozin (DAP) on cardiac Zn²⁺-transporters responsible for [Zn²⁺]_i-regulation, comparison to insulin (INS), together with MMP levels and systemic oxidative stress status in MetS-rats. High-carbohydrated diet-induced MetS-rats received DAP or INS for 2 weeks. DAP but not INS in MetS-rats significantly decreased high blood-glucose levels, while both treatments exerted benefits on increased total oxidative status and decreased total antioxidant status in MetS-rat plasma as well as in heart tissue. Protein levels of Zn²⁺-transporters, responsible for Zn²⁺-influx into cytosol, ZIP7 and ZIP14 were increased with significant decrease in ZIP8 of MetS-rat cardiomyoctes, while Zn²⁺-transporters, responsible for cytosolic Zn²⁺-efflux, ZnT7 was decreased with no change in ZnT8. Both treatments induced significant beneficial effects on altered ZIP14, ZIP8, and ZnT7 levels. Furthermore, both treatments exerted benefits on depressed gelatin-zymography and protein expression levels of MMP-2 and MMP-9 in MetS-rat ventricular cardiomyocytes. The direct effect of DAP on heart was also confirmed with measurements of left ventricular developed pressure. Overall, we showed that DAP has important antioxidant-like cardio-protective effects in MetS-rats, similar to INS-effect, affecting Zn²⁺-regulation via Zn²⁺-transporters, MMPs, and oxidative stress. Therefore one can suggest that SGLT2 inhibitors can be new therapeutic agents for cardio-protection not only in hyperglycemia but also in failing heart.

Dislocation rate increases with bariatric surgery before total hip arthroplasty

INTRODUCTION

Annually in the USA, 113,000 patients with refractory obesity undergo bariatric surgery (BS), and a subset does so in order to lower body mass index to become a more desirable total hip arthroplasty (THA) candidate. This study aims to evaluate THA risk with and without bariatric surgery.

METHODS

12,160 patients were identified in a claim-based review of the entire Medicare database with ICD-9 codes to identify patients in three groups. Patients who underwent BS prior to THA (Group I: 1,545 experimental group) and two control groups that did not undergo BS but had either a body mass index >40 (Group II: 6,918 bariatric control) or <25 (Group III: 3,697 normal weight control). Preoperative demographics/comorbidities and short-term medical (30 day) and long-term surgical (90-day and 2-year) complications were evaluated.

RESULTS

Group I had female predominance, youngest age, and highest incidence of: deficiency anaemia, cardiovascular disease, liver disease, diabetes, polysubstance abuse, psychiatric disorders and smoking. At 2 years, Group I had approximately twice the dislocation and revision risk compared to both Groups II and III; Groups I and II had over four times the risk of infection and wound complications compared to Group III.

CONCLUSION

In the Medicare population, these patients continue to have complication rates similar to and sometimes greater than obese patients with no prior bariatric surgery. Greater dislocation risk is possibly due to ligamentous laxity related to decreased collagen/elastin and/or component malposition due to intraoperative visualisation challenges.

Interleukin 29 activates expression of tissue inhibitor of metalloproteinase 1 in macrophages via toll‑like receptor 2

Obesity and diabetes are characterized by low grade chronic inflammation status and insulin resistance in adipose tissue associated with metalloproteinase inhibitor 1 (TIMP1). Interleukin (IL)29, exhibits multiple immune regulatory activities. However, the role of IL29 and its effects on TIMP1 remain to be elucidated. The present study was designed to investigate the effects of IL29 on expression of TIMP1 in macrophages associated with inflammation in adipose tissue. IL29 and high glucose were used to activate Raw264.7 cells and primary macrophages with or without antibody‑mediated inhibition of toll like receptor (TLR) 2 and TLR4. TIMP1 was measured in culture media of Raw264.7 cells and primary macrophages by ELISA. IL29 and high glucose increased TIMP1 levels in Raw264.7 cells and primary macrophages. Antibody‑mediated inhibition of TLR2 or TLR2 gene knockout decreased TIMP1 levels activated by IL29, however not by high glucose in the medium of Raw264.7 cells and primary macrophages. Furthermore, antibody‑mediated inhibition of TLR4 or TLR4 gene knockout decreased TIMP1 levels which were stimulated by high glucose, not by IL29 in the medium of Raw264.7 cells and primary macrophages. The results of the present study indicate that TLR2 is involved in IL29‑stimulated TIMP1 expression in Raw264.7 cells and primary macrophages.

Morphophysiological changes in the splenic extracellular matrix of Leishmania infantum-naturally infected dogs is associated with alterations in lymphoid niches and the CD4+ T cell frequency in spleens

The spleen is one of the main affected organs in canine visceral leishmaniasis (CVL). Disorganization of the splenic white pulp (SWP) has been associated with immunosuppression and disease progression. This study aims to assess structural and cellular changes in the splenic extracellular matrix of dogs with CVL, correlating these changes with the parasite load and clinical signs. Splenic fragments were collected from 41 naturally infected animals for parasite load quantification by quantitative PCR, histopathological analysis and immunohistochemistry for CD3⁺, CD4⁺, and CD8⁺ T cells; CD21⁺ B cells; Ki-67⁺, IFN-γ⁺, and IL-10⁺ cells; and the MMP-9 and ADAM-10 enzymes. Laminin, collagen and fibronectin deposition were also evaluated. The animals were grouped according to the level of SWP organization. SWP disorganization was accompanied by a reduction in the quantity of lymphoid follicles/mm² (p > 0.0001). Animals with moderate to intense SWP disorganization showed more clinical signs (p = 0.021), higher laminin (p = 0.045) and collagen deposition (p = 0.036), higher MMP-9 expression (p = 0.035) and lower numbers of CD4⁺ T cells (p = 0.027) in the spleen than the animals with organized SWP. These data suggest that splenic structure and function are drastically altered and compromised during CVL.

Infected dogs play important roles in the transmission of visceral leishmaniasis. These dogs are considered reservoirs of parasites in urban areas and fail to mount an efficient anti-Leishmania immune response. However, the specific immunosuppression profile is not completely understood. In our report, we evaluate and discuss the morphophysiological alterations in the spleens of dogs with visceral leishmaniasis. We found an association between extracellular matrix alterations and a failure to control the parasite load. We suggest a role for these alterations in hindering an immune response that is otherwise able to control the parasite load, thereby leading to disease progression. Our research contributes to the current knowledge of the immunopathology of canine visceral leishmaniasis.

Tranexamic Acid Attenuates The Loss of Lung Barrier Function in a Rat Model of Polytrauma And Hemorrhage With Resuscitation

INTRODUCTION

Severe trauma, hemorrhage, and resuscitation can lead to a trauma-related acute lung injury that involves rapid infiltration of immune cells and platelets. This infiltration involves exymatic degradation of matrix proteins, including plasmin, and causes loss of barrier function. Since tranexamic acid (TXA) inhibits plasminogen/ plasmin binding to target substrates, it may attenuate loss of barrier function after severe trauma, hemorrhage, and resuscitation.

METHODS

Sprague-Dawley rats were subjected to polytrauma (laparotomy, and trauma to intestines, liver, right leg skeletal muscle, and right femur fracture), then bled 40% of their blood volume. One hour after completion of polytrauma and hemorrhage, resuscitation was begun with fresh whole blood (FWB) or FWB with prior bolus administration of TXA (10 mg/kg in 0.2 mL).

RESULTS

Polytrauma, hemorrhage, and resuscitation with FWB led to an elevation in lung water content that was significantly reduced with TXA administration. Polytrauma and hemorrhage led to rise in the number of neutrophils/monocytes and platelets in the lungs, and a rise in myeloperoxidase (MPO), neutrophil elastase and complement C5a content. While resuscitation with FWB significantly reduced the cellular infiltrate and MPO, FWB/TXA further reduced the levels of neutrophil/monocytes, neutrophil elastase, and complement C5a. Polytrauma and hemorrhage led to rise in lung plasmin activity that was significantly reduced with either FWB or FWB/TXA resuscitation.

CONCLUSION

Severe trauma and hemorrhage leads to increases in lung water content, and immune cell, platelets, MPO, elastase, and C5a content in lung tissue, all markers of inflammation and acute lung injury. The addition of TXA to FWB resuscitation markedly attenuated the rise in these parameters suggesting its utility in treating acute lung injury.

Toll‑like receptor 2 mediates deposition of collagen I in adipose tissue of high fat diet‑induced obese mice

Obesity is marked by deposition of collagen I in adipose tissue. Toll like receptor (TLR)2 is involved in lipid metabolism, however the association between TLR2 and collagen I remains unclear. The present study was designed to investigate the effect of TLR2 knockout on collagen I in adipose tissue in obese mice. TLR2 knockout and C57BL/6J mice (aged 4 weeks) were fed normal chow or a high‑fat‑diet for 16 weeks. Compared with adipose tissue from lean controls, that from C57BL/6J mice fed a high‑fat diet had increased levels of collagen I, TIMP1 and TGFβ1 and lower levels of MMP1. However, adipose tissue from TLR2 knockout mice fed a high‑fat diet revealed decreased levels of collagen I, TIMP metallopeptidase inhibitor (TIMP)1, and transforming growth factor (TGF)β1, in addition to increased levels of matrix metallopeptidase (MMP)1. These findings suggest that, in the adipose tissue of obese mice, TLR2 is involved in the metabolism of collagen I and may exhibit a role in the metabolism of MMP1, TIMP1 and TGFβ1.

Rice bran protein hydrolysates reduce arterial stiffening, vascular remodeling and oxidative stress in rats fed a high-carbohydrate and high-fat diet

PURPOSE

Rice bran protein hydrolysates (RBPH) contain highly nutritional proteins and antioxidant compounds which show benefits against metabolic syndrome (MetS). Increased arterial stiffness and the components of MetS have been shown to be associated with an increased risk of cardiovascular disease. This study aimed to investigate whether RBPH could alleviate the metabolic disorders, arterial stiffening, vascular remodeling, and oxidative stress in rats fed a high-carbohydrate and high-fat (HCHF) diet.

METHODS

Male Sprague-Dawley rats were fed either a standard chow and tap water or a HCHF diet and 15 % fructose solution for 16 weeks. HCHF rats were treated orally with RBPH (250 or 500 mg/kg/day) for the final 6 weeks of the experimental period.

RESULTS

Rats fed with HCHF diet had hyperglycemia, insulin resistance, dyslipidemia, hypertension, increased aortic pulse wave velocity, aortic wall hypertrophy and vascular remodeling with increased MMP-2 and MMP-9 expression. RBPH supplementation significantly alleviated these alterations (P < 0.05). Moreover, RBPH reduced the levels of angiotensin-converting enzyme (ACE) and tumor necrosis factor-alpha in plasma. Oxidative stress was also alleviated after RBPH treatment by decreasing plasma malondialdehyde, reducing superoxide production and suppressing p47phox NADPH oxidase expression in the vascular tissues of HCHF rats. RBPH increased plasma nitrate/nitrite level and up-regulated eNOS expression in the aortas of HCHF-diet-fed rats, indicating that RBPH increased NO production.

CONCLUSION

RBPH mitigate the deleterious effects of HCHF through potential mechanisms involving enhanced NO bioavailability, anti-ACE, anti-inflammatory and antioxidant properties. RBPH could be used as dietary supplements to minimize oxidative stress and vascular alterations triggered by MetS.

KATP channels in high glucose-induced rat mesangial cell proliferation and release of MMP-2 and fibronectin

ATP-sensitive potassium (KATP) channels are well characterized in cardiac, pancreatic and many other muscle cells. The purpose of this study was to determine if KATP channels play a role in diabetic nephropathy (DN). In the present study, functional expression of the KATP channel was examined in rat mesangial cells with or without high glucose (HG) stimulation. The mesangial cell proliferation and the release of matrix metalloproteinase (MMP)-2 and fibronectin in response to high glucose with a selective opener of KATP (diazoxide, DZX), or with a selective inhibitor of KATP (5-hydroxydecanoate, 5-HD) were also measured. The cell proliferation was observed using Cell Counting Kit-8 assay, and the mRNA expressions of KATP subunit, including Kir6.1, Kir6.2, sulfonylurea receptor 1 (SUR1), SUR2A and SUR2B, were assessed using quantitative real-time PCR. MMP-2 and fibronectin release was measured by ELISA. The present study clarified expression of SUR subunit of KATP in plasma. HG treatment could cause increased cell proliferation and release of MMP-2 and fibronectin in a dose-dependent manner. HG also significantly decreased the expression of Kir6.1, SUR2A and SUR2B. Pretreatment of DZX markedly decreased the expression of SUR1, SUR2A and SUR2B, but had no effect on Kir6.1 expression compared with HG alone, while these changes were inhibited by 5-HD pretreatment. Moreover, DZX also inhibited cell proliferation and release of MMP-2 and fibronectin in HG-induced rat mesangial cells, and that was corrected by 5-HD. These data suggest that HG stimulates mesangial cell proliferation and cellular matrix release via inhibiting KATP channel activity, leading us to propose that KATP channel dysfunction may be involved in the development of DN.

Elevated Serum Cyclophilin B Levels Are Associated with the Prevalence and Severity of Metabolic Syndrome

OBJECTIVE

Inflammation plays a central role in the pathogenesis of metabolic syndrome (MetS). Cyclophilin B (CypB) can be constitutively secreted in response to inflammatory stimuli and oxidative stress, participating in tissue or systemic inflammation. We investigated the relationship between CypB and MetS in both humans and mice.

METHODS

Serum CypB levels were determined in 211 subjects with MetS and 292 subjects without MetS (non-MetS) (133 healthy controls and 159 high-risk subjects with one to two MetS components). Additionally, CypB expression in metabolic organs was examined in mice fed with high-fat diet (HFD) and genetically obese (ob/ob) mice.

RESULTS

Serum CypB level was significantly higher in MetS subjects compared with both groups of non-MetS subjects (193.80 ± 83.22 vs. 168.38 ± 65.01 vs. 124.26 ± 47.83 ng/mL, P < 0.001). Particularly, serum CypB level was significantly higher in subjects with hypertension, central obesity, diabetes mellitus or hyperglycemia, elevated levels of triglycerides, or reduced levels of high-density lipoprotein than in those without. Moreover, CypB was positively associated with the number of MetS components (r = 0.404, P < 0.001), indicating that a higher serum CypB level reflected more severe MetS. Multivariate regression revealed that a one SD increase in CypB was associated with an odds ratio of 1.506 (1.080-2.101, P = 0.016) for MetS prevalence after adjusting for age, gender, conventional risk factors, and medication. Stratified analyses by age and gender demonstrated that subjects >60 years old with higher CypB levels were more likely to have MetS, and the risk for MetS was higher and more significant in women compared with men. Additionally, CypB expression levels were lower at baseline and dramatically enhanced in metabolic organs (such as the liver) and visceral and subcutaneous adipose tissue from HFD-induced obese mice and ob/ob mice.

CONCLUSION

Increased CypB levels were significantly and independently associated with the presence and severity of MetS, indicating that CypB could be used as a novel biomarker and clinical predictor of MetS.

Gelatinases and their tissue inhibitors in a group of subjects with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is associated with an elevated risk of cardiovascular events and stroke. Matrix metalloproteinases (MMPs) are endopeptidases involved in extracellular matrix degradation and then in the development and progression of cardiovascular diseases. Our aim was to evaluate plasma levels of gelatinases (MMP-2 and MMP-9) and their tissue inhibitors (TIMP-1 and TIMP-2) in a group of subjects with OSAS. We enrolled 48 subjects (36 men and 12 women; mean age 49.7 ± 14.68 yrs) with OSAS diagnosed with a 1-night cardiorespiratory study and then we subdivided these subjects into two subgroups according to the apnea/hypopnea index (AHI): Low (L = 21 subjects with AHI <30) and High (H = 27 subjects with AHI >30). We measured plasma concentration of the gelatinases and their inhibitors using ELISA kits. We observed a significant increase in plasma concentration of MMP-9, MMP-2, TIMP-1 and TIMP-2 in the entire group of OSAS subjects and in the two subgroups, with higher levels in the H in comparison with the L subgroup. In the whole group of OSAS subjects we also noted a significant decrease in MMP-9/TIMP-1 ratio in comparison with normal controls. Only MMP-9 was significantly correlated with the severity of the disease, expressed as AHI, with the oxygen desaturation index and also with the mean oxygen saturation. MMPs pattern is altered in OSAS and significantly influenced by the severity of the disease; it probably contributes to the vascular remodeling that leads to the atherosclerotic disease and cardiovascular complications.

Extracellular matrix remodeling and transforming growth factor-β signaling abnormalities induced by lamin A/C variants that cause lipodystrophy

Mutations in the lamin A/C gene encoding nuclear lamins A and C (lamin A/C) cause familial partial lipodystrophy type 2 (FPLD2) and related lipodystrophy syndromes. These are mainly characterized by redistribution of adipose tissue associated with insulin resistance. Several reports suggest that alterations in the extracellular matrix of adipose tissue leading to fibrosis play a role in the pathophysiology of lipodystrophy syndromes. However, the extent of extracellular matrix alterations in FPLD2 remains unknown. We show significantly increased fibrosis and altered expression of genes encoding extracellular matrix proteins in cervical subcutaneous adipose tissue from a human subject with FLPD2. Similar extracellular matrix alterations occur in adipose tissue of transgenic mice expressing an FPLD2-causing human lamin A variant and in cultured fibroblasts from human subjects with FPLD2 and related lipodystrophies. These abnormalities are associated with increased transforming growth factor-β signaling and defects in matrix metalloproteinase 9 activity. Our data demonstrate that lamin A/C gene mutations responsible for FPLD2 and related lipodystrophies are associated with transforming growth factor-β activation and an extracellular matrix imbalance in adipose tissue, suggesting that targeting these alterations could be the basis of novel therapies.

Matrix metalloproteinases in exercise and obesity

Matrix metalloproteinases (MMPs) are zinc- and calcium-dependent endoproteinases that have the ability to break down extracellular matrix. The large range of MMPs’ functions widens their spectrum of potential role as activators or inhibitors in tissue remodeling, cardiovascular diseases, and obesity. In particular, MMP-1, -2, and -9 may be associated with exercise and obesity. Thus, the current study reviewed the effects of different types of exercise (resistance and aerobic) on MMP-1, -2, and -9. Previous studies report that the response of MMP-2 and -9 to resistance exercise is dependent upon the length of exercise training, since long-term resistance exercise training increased both MMP-2 and -9, whereas acute bout of resistance exercise decreased these MMPs. Aerobic exercise produces an inconsistent result on MMPs, although some studies showed a decrease in MMP-1. Obesity is related to a relatively lower level of MMP-9, indicating that an exercise-induced increase in MMP-9 may positively influence obesity. A comprehensive understanding of the relationship between exercise, obesity, and MMPs does not exist yet. Future studies examining the acute and chronic responses of these MMPs using different subject models may provide a better understanding of the molecular mechanisms that are associated with exercise, obesity, and cardiovascular disease.

The Elastin Receptor Complex: A Unique Matricellular Receptor with High Anti-tumoral Potential

Elastin, one of the longest-lived proteins, confers elasticity to tissues with high mechanical constraints. During aging or pathophysiological conditions such as cancer progression, this insoluble polymer of tropoelastin undergoes an important degradation leading to the release of bioactive elastin-derived peptides (EDPs), named elastokines. EDP exhibit several biological functions able to drive tumor development by regulating cell proliferation, invasion, survival, angiogenesis, and matrix metalloproteinase expression in various tumor and stromal cells. Although, several receptors have been suggested to bind elastokines (α_vβ₃ and α_vβ₅ integrins, galectin-3), their main receptor remains the elastin receptor complex (ERC). This heterotrimer comprises a peripheral subunit, named elastin binding protein (EBP), associated to the protective protein/cathepsin A (PPCA). The latter is bound to a membrane-associated protein called Neuraminidase-1 (Neu-1). The pro-tumoral effects of elastokines have been linked to their binding onto EBP. Additionally, Neu-1 sialidase activity is essential for their signal transduction. Consistently, EDP-EBP interaction and Neu-1 activity emerge as original anti-tumoral targets. Interestingly, besides its direct involvement in cancer progression, the ERC also regulates diabetes outcome and thrombosis, an important risk factor for cancer development and a vascular process highly increased in patients suffering from cancer. In this review, we will describe ERC and elastokines involvement in cancer development suggesting that this unique receptor would be a promising therapeutic target. We will also discuss the pharmacological concepts aiming at blocking its pro-tumoral activities. Finally, its emerging role in cancer-associated complications and pathologies such as diabetes and thrombotic events will be also considered.

Imbalanced insulin action in chronic over nutrition: Clinical harm, molecular mechanisms, and a way forward

The growing worldwide prevalence of overnutrition and underexertion threatens the gains that we have made against atherosclerotic cardiovascular disease and other maladies. Chronic overnutrition causes the atherometabolic syndrome, which is a cluster of seemingly unrelated health problems characterized by increased abdominal girth and body-mass index, high fasting and postprandial concentrations of cholesterol- and triglyceride-rich apoB-lipoproteins (C-TRLs), low plasma HDL levels, impaired regulation of plasma glucose concentrations, hypertension, and a significant risk of developing overt type 2 diabetes mellitus (T2DM). In addition, individuals with this syndrome exhibit fatty liver, hypercoagulability, sympathetic overactivity, a gradually rising set-point for body adiposity, a substantially increased risk of atherosclerotic cardiovascular morbidity and mortality, and--crucially--hyperinsulinemia. Many lines of evidence indicate that each component of the atherometabolic syndrome arises, or is worsened by, pathway-selective insulin resistance and responsiveness (SEIRR). Individuals with SEIRR require compensatory hyperinsulinemia to control plasma glucose levels. The result is overdrive of those pathways that remain insulin-responsive, particularly ERK activation and hepatic de-novo lipogenesis (DNL), while carbohydrate regulation deteriorates. The effects are easily summarized: if hyperinsulinemia does something bad in a tissue or organ, that effect remains responsive in the atherometabolic syndrome and T2DM; and if hyperinsulinemia might do something good, that effect becomes resistant. It is a deadly imbalance in insulin action. From the standpoint of human health, it is the worst possible combination of effects. In this review, we discuss the origins of the atherometabolic syndrome in our historically unprecedented environment that only recently has become full of poorly satiating calories and incessant enticements to sit. Data are examined that indicate the magnitude of daily caloric imbalance that causes obesity. We also cover key aspects of healthy, balanced insulin action in liver, endothelium, brain, and elsewhere. Recent insights into the molecular basis and pathophysiologic harm from SEIRR in these organs are discussed. Importantly, a newly discovered oxide transport chain functions as the master regulator of the balance amongst different limbs of the insulin signaling cascade. This oxide transport chain--abbreviated 'NSAPP' after its five major proteins--fails to function properly during chronic overnutrition, resulting in this harmful pattern of SEIRR. We also review the origins of widespread, chronic overnutrition. Despite its apparent complexity, one factor stands out. A sophisticated junk food industry, aided by subsidies from willing governments, has devoted years of careful effort to promote overeating through the creation of a new class of food and drink that is low- or no-cost to the consumer, convenient, savory, calorically dense, yet weakly satiating. It is past time for the rest of us to overcome these foes of good health and solve this man-made epidemic.

The response of matrix metalloproteinase-9 and -2 to exercise

BACKGROUND

Matrix metalloproteinases (MMPs) are a major group of enzymes that play essential roles in normal functioning of diverse tissues during growth, development, and aging. However, among the MMPs little is known regarding the role of exercise in MMP-9 and MMP-2 function in humans.

OBJECTIVE

The aim of this study was to provide a systematic comprehensive review of the literature examining the effect of different exercise interventions on MMP-9 and MMP-2 in human investigations.

DATA SOURCES

A comprehensive systematic database search was performed, including PubMed/MEDLINE, Scopus, ScienceDirect, and Web of Science.

STUDY SELECTION

Both the acute and chronic effects of exercise were included for evaluation in this systematic review. Inclusion criteria included the use of any type of planned, structured, and repetitive movement and its effects on the MMP-2 and MMP-9 response (obtained from plasma samples), participants (humans only) of any age with or without diseases, sedentary participants and those involved in light, moderate, and vigorous activity, randomized controlled trials (RCTs) and clinical trials (CTs), full text article citations with no restrictions in terms of language, and scored at least 5/11 on the Physiotherapy Evidence Database (PEDro) quality scale.

STUDY APPRAISAL AND SYNTHESIS METHODS

The PEDro scale was used to appraise study quality of RCTs and CTs. Two reviewers independently reviewed the full texts of all potentially relevant articles for eligibility and disagreements were discussed and resolved.

RESULTS

Seven studies met the previously determined quality indicators and were reviewed; three were RCTs and four were CTs. In general, the quality of the studies ranged from 5 to 9 out of a maximum of 11 on the PEDro quality criteria scale. Results revealed that chronic aerobic training induces a decrease in MMP-9 and MMP-2 levels, possibly indicating a cardioprotective effect, while resistance exercise training displayed conflicting results.

CONCLUSION

Alterations in MMP-9 and MMP-2 plasma concentrations may be valuable biomarkers to reflect the influence of exercise on the inflammatory state. Nevertheless, the limited evidence available regarding the effects of exercise on the MMP-9 and MMP-2 response in human participants suggests that further studies are needed to fully define the connection between the role of exercise on the MMP-9 and MMP-2 response.

CD11c(+) macrophages and levels of TNF-α and MMP-3 are increased in synovial and adipose tissues of osteoarthritic mice with hyperlipidaemia

To understand more clearly the link between osteoarthritis and hyperlipidaemia, we investigated the inflammatory macrophage subsets and macrophage-regulated matrix metalloprotease-3 (MMP-3) and A disintegrin and metalloprotease with thrombospondin motifs-4 (ADAMTS4) in synovial (ST) and adipose tissues (AT) of osteoarthritic mice with hyperlipidaemia (STR/Ort). CD11c(+) F4/80(+) CD11b(+) macrophage populations in the ST and AT of 9-month-old STR/Ort and C57BL/6J mice were characterized and compared by flow cytometry and real-time polymerase chain reaction (PCR) analyses. Expression of tumour necrosis factor (TNF)-α, MMP-3 and ADAMTS4, and the response of these factors to anionic liposomal clodronate induced-macrophage depletion were also evaluated by real-time PCR. Expression of TNF-α in CD11c(+) cells, which were isolated by magnetic beads, was compared to CD11c(-) cells. In addition, the effect of TNF-α on cultured synovial fibroblasts and adipocytes was investigated. CD11c(+) F4/80(+) CD11b(+) macrophages were increased in ST and AT of STR/Ort mice. The CD11c(+) cell fraction highly expressed TNF-α. Expression of TNF-α and MMP3 was increased in ST and AT, and was decreased upon macrophage depletion. TNF-α treatment of cultured synovial fibroblasts and adipocytes markedly up-regulated MMP-3. CD11c(+) F4/80(+) CD11b(+) macrophages were identified as a common inflammatory subset in the AT and ST of STR/Ort mice with hyperlipidaemia. The induction of inflammation in AT and ST may be part of a common mechanism that regulates MMP3 expression through TNF-α. Our findings suggest that increased numbers of CD11c(+) macrophages and elevated levels of TNF-α and MMP-3 in AT and ST may explain the relationship between hyperlipidaemia and OA.

Evaluation of plasma MMP-8, MMP-9 and TIMP-1 identifies candidate cardiometabolic risk marker in metabolic syndrome: results from double-blinded nested case-control study

AIMS

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) are dysregulated in metabolic syndrome (MetS) and associated with atherosclerosis and cardiovascular disease (CVD). Previous studies on the association between MMPs/TIMPs and MetS are controversial. We aimed to evaluate circulating MMP-8, MMP-9 and TIMP-1 in a group of MetS individuals and healthy controls to find the potential marker associated with MetS and its components.

METHODS

243 MetS individuals participated in a nested case-control design, of whom 63 were excluded (study subjects for analysis n=180; 87 MetS cases, 93 controls). We employed the International Diabetes Federation criteria using national waist circumference cutoffs for case definition. Anthropometric and biochemical measurements were done using standard methods.

RESULTS

Plasma MMP-8, TIMP-1, tumor necrosis factor-alpha (TNF-α), highly sensitive C-reactive protein (hs-CRP) and MMP-8/TIMP-1 ratio were significantly higher in MetS cases (P for all < 0.05). Each component of MetS except raised fasting plasma glucose positively correlated with MMP-8 and numbers of MetS components increased with higher MMP-8. In all regression models, MMP-8 was a significant predictor of MetS and in the final model the relationship persisted even after adjusting for pro-inflammatory cytokines hs-CRP and TNF-α (odds ratio=6.008, 95% confidence interval: 1.612-22.389, P=0.008).

CONCLUSION

Strong associations of MMP-8 with components of MetS in univariate, bivariate and multivariate models suggest plasma MMP-8 as a potential cardiometabolic risk marker for MetS. Higher MMP-8 in MetS is possibly mediated through mechanisms both dependent and independent of chronic low grade inflammation.

Extracellular matrix in obesity – cancer interactions

Obesity or overweight is a risk factor for several health disorders such as type 2 diabetes, hypertension, and certain cancers. Furthermore, obesity affects almost all body systems including the extracellular matrix (ECM) by generating a pro-inflammatory environment, which are associated with abnormal secretions of several cytokines or hormonal substances, for example, insulin-like growth factors (IGFs), leptin, and sex hormones. These chemical mediators most likely have a great impact on the ECM. Accumulating evidence suggests that both obesity and ECM can influence tumor growth and progression through a number of chemical mediators. Conversely, cells in the connective tissue, namely fibroblasts and macrophages, support and aggravate the inflammatory situation in obesity by releasing several cytokines or growth factors such as vascular endothelial growth factor, epidermal growth factor, and transforming growth factor-beta (TGF-β). A wide range of functions are performed by TGF-β in normal health and pathological conditions including tumorigenesis. Breast cancer in postmenopausal women is a classic example of obesity-related cancer wherein several of these conditions, for example, higher levels of pro-inflammatory cytokines, impairment in the regulation of estrogen and growth factors, and dysregulation of different ECM components may favor the neoplastic process. Aberrant expressions of ECM components such as matrix metalloproteinases or matricellular proteins in both obesity and cancer have been reported by many studies. Nonstructural matricellular proteins, viz., thrombospondins, secreted protein acidic and rich in cysteine (SPARC), and Cyr61-CTGF-Nov (CCN), which function as modulators of cell-ECM interactions, exhibit protean behavior in cancer. Precise understanding of ECM biology can provide potential therapeutic targets to combat obesity-related pathologies.

High serum level of matrix metalloproteinase 9 and promoter polymorphism - 1562 C:T as a new risk factor for metabolic syndrome

The altered matrix metalloproteinases (MMPs) have been suggested in the pathophysiology of metabolic syndrome (MetS). Genetic variants in the promoter region of MMP1 and MMP9 genes may modulate an individual's susceptibility to MetS. The aim of this study was to determine the frequency of MMP1 -519 A:G and MMP9 -1562 C:T polymorphisms and the correlation with serum levels of MMP1 and MMP9 in MetS susceptibility. On the basis of anthropometric profile and laboratory investigations, 180 confirmed MetS patients and 190 unrelated healthy controls of similar ethnicity were genotyped for MMP1 -519 A:G and MMP9-1562 C:T polymorphisms by using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) methods. In addition, serum levels of MMP1 and MMP9 were quantified by ELISA. We found that the serum level of MMP9 was significantly higher in MetS patients. Variant genotype TT of MMP9 -1562 demonstrated increased risk (odds ratio [OR]=3.70, p=0.015) of MetS. Similarly, variant allele T (OR=1.77, p=0.002) and combined genotype CT+TT (OR=1.81, p=0.057) also showed a significantly higher risk. The CT and TT genotypes of MMP9 -1562 polymorphism contributed to high serum levels of MMP9 in MetS patients. However, no such association was observed with the MMP1 serum level and -519 A:G polymorphism. Our results suggest that a higher serum level of MMP9 in the presence of MMP9 polymorphism -1562 C:T might be a risk factor for the development of MetS. The MMP9 enzyme activity might be a significant indicator in the screening of MetS patients.

Effects of reduced β2-glycoprotein I on the expression of aortic matrix metalloproteinases and tissue inhibitor matrix metalloproteinases in diabetic mice

Background

Reduced β₂-glycoprotein I (reduced β₂GP I), which has free sulfhydryl groups, is present in plasma and serum; it can protect vascular endothelial cells from damage due to oxidative stress in vitro. We investigated the effects of reduced β₂GP I on the expression of various matrix metalloproteinases (MMPs) and tissue inhibitors of matrix metalloproteinases (TIMPs) in the aortas of diabetic mice.

Methods

We provided 120 female 8-week-old Balb/c mice with a high sugar, high fat diet. After 8 weeks they were injected with streptozotocin to induce diabetes. We treated mice in the mono dose groups with β₂GP I, reduced β₂GP I, or phosphate-buffered saline (PBS) on day 1 and fed them for 3 weeks. The mice in the complex dose groups were treated with β₂GP I, reduced β₂GP I, or PBS on days 1 and 22 and fed for 6 weeks. Control mice were given a standard chow diet. Blood lipids were measured at the end of 3 or 6 weeks, and aortas removed to observe morphological and molecular biological changes.

Results

The low-density lipoprotein cholesterol levels in mice of the reduced β₂GP I group were lower than those in the diabetic group. Aortic lipid deposition in the reduced β₂GP I group was significantly less than in the diabetic control group. In the aortas, reduced β₂GP I decreased MMP2/TIMP2 mRNA and protein expression levels, and MMP9/TIMP1 expression levels compared with those in diabetic controls. Reduced β₂GP I down-regulated p38 mitogen-activated protein kinase (p38MAPK) mRNA expression and phosphorylated p38MAPK protein expression compared with those in diabetic controls of the complex dose group.

Conclusions

Reduced β₂GP I plays a role in diabetic mice related to vascular protection, inhibiting vascular lipid deposition, and plaque formation by reducing MMPs/TIMPs expression through down-regulation of the p38MAPK signaling pathway.

The MMP-9 -1562 C/T polymorphism in the presence of metabolic syndrome increases the risk of clinical events in patients with coronary artery disease

BACKGROUND AND OBJECTIVES

Elevated levels of matrix metalloproteinase (MMP)-9 have been associated with the metabolic syndrome (MetS) and cardiovascular events. The MMP-9 -1562 C/T polymorphism has furthermore been shown as a risk factor for coronary artery disease (CAD). The non-favourable cardiometabolic state in MetS may increase the risk. We aimed to investigate the influence of MMP-9 -1562 C/T polymorphism in subjects with CAD and MetS.

METHODS

Patients (n = 1000) with verified CAD stratified in Mets +/- (n = 244/756), were analyzed for the MMP-9 -1562 C/T polymorphism and related to clinical events after 2 years follow-up. Serum levels of total MMP-9 and tissue inhibitor of matrix metalloproteinases (TIMP)-1 were analyzed in all, whereas MMP-9 activity, extracellular matrix metalloproteinase inducer (EMMPRIN), and expression of the two genes were analyzed in a subset of 240 randomly selected patients.

RESULTS

Totally, 106 clinical endpoints were recorded. In MetS; the T-allele associated with 5.5 fold increase in event rate (p<0.0001), increased with number of MetS components, a 117% increase in total MMP-9 levels (TT homozygous, p = 0.05), significantly higher total- and endogenous active MMP-9 and TIMP-1 levels (p<0.01 all), and EMMPRIN was inversely correlated with pro- and endogenous active MMP-9 (p<0.05, both). In non-MetS; the T-allele was not associated with new events, nor higher MMP-9 levels. EMMPRIN was significantly correlated with total MMP-9 and TIMP-1 (p<0.01, both) and the two genes were inter-correlated (p<0.001).

CONCLUSION

In CAD patients with MetS, the MMP-9 T-allele increased the risk of clinical events, probably mediated through elevated MMP-9 levels and altered MMP-9 regulation.

Exercise-induced regulation of matrix metalloproteinases in the skeletal muscle of subjects with type 2 diabetes

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMP) play a critical role during vascular remodelling, in both health and disease. Impaired MMP regulation is associated with many diabetes-related complications. This study examined whether exercise-induced regulation of MMPs is maintained in the skeletal muscle of patients with uncomplicated type 2 diabetes (T2DM). Subjects [12 T2DM, 9 healthy control subjects (CON)] underwent 8 weeks of physical training. Messenger RNA (mRNA) was measured at baseline, during and after 8 weeks of training. Protein was measured pre- and post-training. At baseline, there were no effects of diabetes on MMP or TIMP mRNA or protein. mRNA and protein response to training was similar in both groups, except active MMP-2 protein was elevated post training in T2DM only. Our results indicate that exercise-induced stimulation of MMPs is preserved in skeletal muscle of patients with T2DM. This early stage of diabetes may provide an opportunity for intervention and prevention of complications.

Study of the correlations among some parameters of the oxidative status, gelatinases, and their inhibitors in a group of subjects with metabolic syndrome

Our aim was to examine some parameters of oxidative status, gelatinases, and their inhibitors and to evaluate their interrelationships in subjects with metabolic syndrome (MS). We enrolled 65 MS subjects, subdivided according to the presence or not of diabetes mellitus. We examined lipid peroxidation (expressed as thiobarbituric acid reacting substances, TBARS), protein oxidation (expressed as carbonyl groups), nitric oxide metabolites (NO_x), total antioxidant status (TAS), MMP-2, MMP-9, TIMP-1, and TIMP-2. We found that MS subjects, diabetics and nondiabetics, showed an increase in TBARS, PC, and NO_x. A significant decrease in TAS was observed only in nondiabetic MS subjects in comparison with diabetic MS subjects. We observed increased concentrations of MMP-2, MMP-9, TIMP-1, and TIMP-2, higher in diabetic subjects. Our data showed a positive correlation between TAS and MMP-2, TAS and MMP-9, and TAS and MMP-9/TIMP-1 and a negative correlation between TBARS and MMP-2 in diabetic MS subjects in the entire group. In MS subjects a prooxidant status and increased levels of gelatinases and their inhibitors are evident although the correlations between oxidative stress and MMPs or TIMPs are controversial and need further investigation.