Metalloproteinases and Tissue Inhibitors in Generalized Myasthenia Gravis. A Preliminary Study

INTRODUCTION

Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) have recently been proposed as promising biomarkers in different immune-mediated disorders. We evaluated the plasma levels of MMP-9 and MMP-2 and their tissue inhibitors TIMP-1 and TIMP-2 in a patients' cohort with generalized myasthenia gravis (MG).

METHODS

Plasma concentrations of MMP-9, MMP-2, TIMP-1 and TIMP-2 were evaluated in 14 patients with generalized MG and 13 age- and sex-matched healthy controls. The severity of disease was assessed by the modified Osserman classification.

RESULTS

Compared to the healthy subjects, MG patients had increased plasma concentrations of MMP-9, but reduced plasma levels of MMP-2 and TIMP-1. MG patients also showed a positive correlation between MMP-2 concentrations and disease severity. An increase in MMP-9 levels and MMP-9/TIMP-1 ratio and a decrease in MMP-2 levels and MMP-2/TIMP-2 ratio were detected in patients with generalized MG. Higher levels of MMP-2 correlated with greater disease severity.

DISCUSSION

Our preliminary findings suggest that MMPs and TIMPs could play a role in the pathogenesis of MG and might be associated with the risk of clinical deterioration.

Serum activity of matrix metalloproteinase-2 and -9 is increased in chronic post-stroke individuals: a cross-sectional exploratory study

BACKGROUND

High concentrations of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) are associated with inflammation early after stroke. In chronic stages, the elevation of some cytokines is related to the presence of co-morbid conditions in these individuals. In addition to this, some characteristics such as sensorimotor impairment, atrophy, and sedentary lifestyle predispose the system to an inflammatory response.

OBJECTIVE

To quantify MMP-2 and -9 serum activity in chronic post-stroke individuals and correlate it with variables of physical activity level, body composition, functional and walking capacity, and with inflammatory biomarkers. Additionally, gelatinase activity was characterized according to motor impairment.

METHODS

Fourteen patients with stroke onset >6 months and seven healthy individuals were enrolled in this study. The clinical assessment included: body composition, measure by bioelectrical impedance analyzer; Fugl-Meyer Motor Assessment Scale; six-minute and ten-meter walk tests, and physical activity level assessed by the StepWatch® Activity Monitor. Blood samples were collected from antecubital vein and serum MMP-2 and -9 activity was analyzed using gelatin Zymography, and the TNFα, IL-6, IL-1β, IL-10 biomarkers using ELISA kits.

RESULTS

Chronic post-stroke individuals presented an increased activity of MMP-2 and -9 compared to healthy individuals. Positive correlations with time and steps in low cadence and negative ones with medium cadence and peak activity index were observed. According to the motor impairment, the MMP-2 activity was increased in the mild-moderate group compared to the control group.

CONCLUSION

Increased gelatinases in chronic post-stroke individuals could describe an inflammation process related to the limited capacity of walking in high intensities.

Expression pattern of matrix metalloproteinases-2 and -9 and their tissue inhibitors in patients with chronic inflammatory demyelinating polyneuropathy

BACKGROUND

Matrix metalloproteinases (MMPs) are a heterogeneous family of endopeptidases that play a role in many physiological functions, including the immune response. An imbalance between the activity of MMPs and their physiological tissue inhibitors (TIMPs) has been proposed in the pathophysiology of different autoimmune disorders. We aimed to assess the plasmatic levels of MMP-2, MMP-9, and their inhibitors TIMP-1 and -2 in patients with chronic inflammatory demyelinating polyneuropathy (CIDP).

SUBJECTS AND METHODS

Twenty patients with CIDP and 20 age- and sex-matched healthy controls were enrolled. Plasma concentrations of MMP-2, MMP-9, TIMP-1, and TIMP-2 were determined by the enzyme-linked immunosorbent assay.

RESULTS

CIDP subjects had higher MMP-9 concentrations along with TIMP-1 downregulation when compared to controls, with the consequent increase in the MMP-9/TIMP-1 ratio (p<0.000002 for all measures). Conversely, the concentration of MMP-2 was lower in the CIDP group (p<0.01) without changes in the TIMP-2 concentration. The MMP-2/TIMP-2 ratio was decreased in the patients' group (p<0.02).

DISCUSSION

We provide first preliminary evidence that the plasmatic pattern of MMPs and TIMPs is markedly altered in patients with CIDP. Future studies are needed to assess the potential usefulness of these new biomarkers in the clinical setting.

Impact of MMP2 rs243865 and MMP3 rs3025058 Polymorphisms on Clinical Findings in Alzheimer's Disease Patients

Alzheimer's disease (AD) is a chronic neurodegenerative disease of the central nervous system with higher prevalence in elderly people. Despite numerous research studies, the etiopathogenesis of AD remains unclear. Matrix metalloproteinases (MMPs) are endopeptidases involved in the cleavage of extracellular matrix proteins and basement membrane compounds. In the brain, the pathological role of MMPs includes the disruption of the blood-brain barrier leading to the induction of neuroinflammation. Among various MMPs, MMP-2 and MMP-3 belong to candidate molecules related to AD pathology. In our study, we aimed to evaluate the association of MMP2 rs243865 and MMP3 rs3025058 polymorphisms with AD susceptibility and their influence on age at onset and MoCA score in patients from Slovakia. Both MMP gene promoter polymorphisms were genotyped in 171 AD patients and 308 controls by the PCR-RFLP method. No statistically significant differences in the distribution of MMP2 rs243865 (-1306 C>T) and MMP3 rs3025058 (-1171 5A>6A) alleles/genotypes were found between AD patients and the control group. However, correlation with clinical findings revealed later age at disease onset in MMP2 rs243865 CC carriers in the dominant model as compared to T allele carriers (CC vs. CT+TT: 78.44 ± 6.28 vs. 76.36 ± 6.39, p = 0.036). The results of MMP3 rs3025058 analysis revealed that 5A/6A carriers in the overdominant model tended to have earlier age at disease onset as compared to other MMP3 genotype carriers (5A/6A vs. 5A/5A+6A/6A: 76.61 ± 5.88 vs. 78.57 ± 6.79, p = 0.045). In conclusion, our results suggest that MMP2 rs243865 and MMP3 rs3025058 promoter polymorphisms may have influence on age at onset in AD patients.

Inherited Neuromuscular Disorders: Which Role for Serum Biomarkers?

Inherited neuromuscular disorders (INMD) are a heterogeneous group of rare diseases that involve muscles, motor neurons, peripheral nerves or the neuromuscular junction. Several different lab abnormalities have been linked to INMD: sometimes they are typical of the disorder, but they usually appear to be less specific. Sometimes serum biomarkers can point out abnormalities in presymtomatic or otherwise asymptomatic patients (e.g., carriers). More often a biomarker of INMD is evaluated by multiple clinicians other than expert in NMD before the diagnosis, because of the multisystemic involvement in INMD. The authors performed a literature search on biomarkers in inherited neuromuscular disorders to provide a practical approach to the diagnosis and the correct management of INMD. A considerable number of biomarkers have been reported that support the diagnosis of INMD, but the role of an expert clinician is crucial. Hence, the complete knowledge of such abnormalities can accelerate the diagnostic workup supporting the referral to specialists in neuromuscular disorders.

How matrix metalloproteinase (MMP)-9 (rs3918242) polymorphism affects MMP-9 serum concentration and associates with autism spectrum disorders: A case-control study in Iranian population

The aim of this project was to evaluate the relationship of matrix metalloproteinase-9 (MMP-9) genetic variation and its serum concentration with autism spectrum disorder (ASD). One hundred ASD and 120 controls were enrolled in this study. Genomic DNA was extracted from blood and MMP-9 polymorphism was determined by polymerase chain reaction restriction fragment length polymorphism and serum levels were measured by enzyme-linked immunosorbent assay. The frequencies of CC, CT, and TT genotypes were 72%, 26%, and 2% in controls and 31%, 57%, and 12% in ASD, respectively. The frequencies of C and T alleles in ASD were 59.5% and 40.5%, and controls were 86% and 14%, respectively. There is a significant increase in serum MMP-9 levels in ASD as compared to controls. We have also shown that TT genotype is significantly associated with increase serum MMP-9 levels in patients (TT, CT, and CC serum levels were 91.77 ± 10.53, 70.66 ± 7.21, and 38.66 ± 5.52 and in controls were 55.55 ± 11.39, 42.66 ± 7.85, and 30.55 ± 6.34 ng/ml, respectively). It is concluded that there is a significant association between rs3918242 MMP-9 polymorphism and its serum concentration with autism. We also suggest that TT genotype is associated with increased MMP9 expression and may be a risk factor for ASD.

Matrix metalloproteinases deregulation in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by the loss of upper and lower motor neurons that results in progressive paralysis and muscular atrophy. There are many molecules and genes involved in neuromuscular degeneration in ALS; among these, matrix metalloproteinases (MMPs). MMPs play an important role in the pathology of ALS, and MMP-1, 2, 3, and 9 might serve as disease progression markers. Tissue inhibitors of metalloproteinases (TIMPS) might also function as progression markers in ALS because they participate in regulating the proteolytic activity of MMPs. Moreover, a diversity of genes also plays a role in the pathogenesis of ALS; most MMPs-coding genes present variants related to the pathological proteolytic activity. This short review, however, will focus on the role of matrix metalloproteinases in ALS.

Toxoplasma gondii infection damages the perineuronal nets in a murine model

BACKGROUND

Behavioral and neurochemical alterations associated with toxoplasmosis may be influenced by the persistence of tissue cysts and activation of an immune response in the brain of Toxoplasma gondii-infected hosts. The cerebral extracellular matrix is organised as perineuronal nets (PNNs) that are both released and ensheath by some neurons and glial cells. There is evidences to suggest that PNNs impairment is a pathophysiological mechanism associated with neuropsychiatric conditions. However, there is a lack of information regarding the impact of parasitic infections on the PNNs integrity and how this could affect the host’s behavior.

OBJECTIVES

In this context, we aimed to analyse the impact of T. gondii infection on cyst burden, PNNs integrity, and possible effects in the locomotor activity of chronically infected mice.

METHODS

We infected mice with T. gondii ME-49 strain. After thirty days, we assessed locomotor performance of animals using the open field test, followed by evaluation of cysts burden and PNNs integrity in four brain regions (primary and secondary motor cortices, prefrontal and somesthetic cortex) to assess the PNNs integrity using Wisteria floribunda agglutinin (WFA) labeling by immunohistochemical analyses.

FINDINGS AND MAIN CONCLUSIONS

Our findings revealed a random distribution of cysts in the brain, the disruption of PNNs surrounding neurons in four areas of the cerebral cortex and hyperlocomotor behavior in T. gondii-infected mice. These results can contribute to elucidate the link toxoplasmosis with the establishment of neuroinflammatory response in neuropsychiatric disorders and to raise a discussion about the mechanisms related to changes in brain connectivity, with possible behavioral repercussions during chronic T. gondii infection.

Blood substitution therapy rescues the brain of mice from ischemic damage

Acute stroke causes complex, pathological, and systemic responses that have not been treatable by any single medication. In this study, using a murine transient middle cerebral artery occlusion stroke model, a novel therapeutic strategy is proposed, where blood replacement (BR) robustly reduces infarctions and improves neurological deficits in mice. Our analyses of immune cell subsets suggest that BR therapy substantially decreases neutrophils in blood following a stroke. Electrochemiluminescence detection demonstrates that BR therapy reduces cytokine storm in plasma and ELISA demonstrates reduced levels of matrix metalloproteinase-9 (MMP-9) in the plasma and brains at different time points post-stroke. Further, we have demonstrated that the addition of MMP-9 to the blood diminishes the protective effect of the BR therapy. Our study is the first to show that BR therapy leads to profoundly improved stroke outcomes in mice and that the improved outcomes are mediated via MMP-9. These results offer new insights into the mechanisms of stroke damage.

Acute stroke causes complex, pathological, and systemic responses which remain challenging to treat. Here, the authors show that substituting the blood of stroke model mice with whole-blood from naive healthy donor mice reduces infarct volume and improves neurological deficits.

Repurposing of Secukinumab as Neuroprotective in Cuprizone-Induced Multiple Sclerosis Experimental Model via Inhibition of Oxidative, Inflammatory, and Neurodegenerative Signaling

Multiple sclerosis (MS) is a chronic, inflammatory, and neurodegenerative autoimmune disease. MS is a devastating disorder that is characterized by cognitive and motor deficits. Cuprizone-induced demyelination is the most widely experimental model used for MS. Cuprizone is a copper chelator that is well characterized by microgliosis and astrogliosis and is reproducible for demyelination and remyelination. Secukinumab (SEC) is a fully human monoclonal anti-human antibody of the IgG1/kappa isotype that selectively targets IL-17A. Expression of IL-17 is associated with MS. Also, IL-17 stimulates microglia and astrocytes resulting in progression of MS through chemokine production and neutrophil recruitment. This study aimed to investigate the neuroprotective effects of SEC on cuprizone-induced demyelination with examining the underlying mechanisms. Locomotor activity, short-term spatial memory function, staining by Luxol Fast Blue, myelin basic protein, gliasosis, inflammatory, and oxidative-stress markers were assessed to evaluate neuroprotective, anti-inflammatory and antioxidant effects. Moreover, the safety profile of SEC was evaluated. The present study concludes the efficacy of SEC in Cup-induced demyelination experimental model. Interestingly, SEC had neuroprotective and antioxidant effects besides its anti-inflammatory effect in the studied experimental model of MS. Graphical abstract.

Myasthenia Gravis: From the Viewpoint of Pathogenicity Focusing on Acetylcholine Receptor Clustering, Trans-Synaptic Homeostasis and Synaptic Stability

Myasthenia gravis (MG) is a disease of the postsynaptic neuromuscular junction (NMJ) where nicotinic acetylcholine (ACh) receptors (AChRs) are targeted by autoantibodies. Search for other pathogenic antigens has detected the antibodies against muscle-specific tyrosine kinase (MuSK) and low-density lipoprotein-related protein 4 (Lrp4), both causing pre- and post-synaptic impairments. Agrin is also suspected as a fourth pathogen. In a complex NMJ organization centering on MuSK: (1) the Wnt non-canonical pathway through the Wnt-Lrp4-MuSK cysteine-rich domain (CRD)-Dishevelled (Dvl, scaffold protein) signaling acts to form AChR prepatterning with axonal guidance; (2) the neural agrin-Lrp4-MuSK (Ig1/2 domains) signaling acts to form rapsyn-anchored AChR clusters at the innervated stage of muscle; (3) adaptor protein Dok-7 acts on MuSK activation for AChR clustering from “inside” and also on cytoskeleton to stabilize AChR clusters by the downstream effector Sorbs1/2; (4) the trans-synaptic retrograde signaling contributes to the presynaptic organization via: (i) Wnt-MuSK CRD-Dvl-β catenin-Slit 2 pathway; (ii) Lrp4; and (iii) laminins. The presynaptic Ca²⁺ homeostasis conditioning ACh release is modified by autoreceptors such as M1-type muscarinic AChR and A2A adenosine receptors. The post-synaptic structure is stabilized by: (i) laminin-network including the muscle-derived agrin; (ii) the extracellular matrix proteins (including collagen Q/perlecan and biglycan which link to MuSK Ig1 domain and CRD); and (iii) the dystrophin-associated glycoprotein complex. The study on MuSK ectodomains (Ig1/2 domains and CRD) recognized by antibodies suggested that the MuSK antibodies were pathologically heterogeneous due to their binding to multiple functional domains. Focussing one of the matrix proteins, biglycan which functions in the manner similar to collagen Q, our antibody assay showed the negative result in MG patients. However, the synaptic stability may be impaired by antibodies against MuSK ectodomains because of the linkage of biglycan with MuSK Ig1 domain and CRD. The pathogenic diversity of MG is discussed based on NMJ signaling molecules.

The Role of Matrix Metalloproteinases (MMP-2 and MMP-9) in Ageing and Longevity: Focus on Sicilian Long-Living Individuals (LLIs)

Extracellular matrix metalloproteinases (MMPs) are a group of proteins that activate substrates by enzymatic cleavage and, on the basis of their activities, have been demonstrated to play a role in ageing. Thus, in order to gain insight into the pathophysiology of ageing and to identify new markers of longevity, we analysed the activity levels of MMP-2 and MMP-9 in association with some relevant haematochemical parameters in a Sicilian population, including long-living individuals (LLIs, ≥95 years old). A cohort of 154 healthy subjects (72 men and 82 women) of different ages (age range 20-112) was recruited. The cohort was divided into five subgroups: the first group with subjects less than 40 years old, the second group ranging from 40 to 64 years old, the third group ranging from 65 to 89 years old, the fourth group ranging from 90 to 94 years old, and the fifth group with subjects more than 95 years old. A relationship was observed between LLIs and MMP-2, but not between LLIs and MMP-9. However, in the LLI group, MMP-2 and MMP-9 values were significantly correlated. Furthermore, in LLIs, we found a positive correlation of MMP-2 with the antioxidant catabolite uric acid and a negative correlation with the inflammatory marker C-reactive protein. Finally, in LLIs MMP-9 values correlated directly both with cholesterol and with low-density lipoproteins. On the whole, our data suggest that the observed increase of MMP-2 in LLIs might play a positive role in the attainment of longevity. This is the first study that shows that serum activity of MMP-2 is increased in LLIs as compared to younger subjects. As far as we are concerned, it is difficult to make wide-ranging conclusions/assumptions based on these observations in view of the relatively small sample size of LLIs. However, this is an important starting point. Larger-scale future studies will be required to clarify these findings including the link with other systemic inflammatory and antioxidant markers.

MMPs in learning and memory and neuropsychiatric disorders

Matrix metalloproteinases (MMPs) are a group of over twenty proteases, operating chiefly extracellularly to cleave components of the extracellular matrix, cell adhesion molecules as well as cytokines and growth factors. By virtue of their expression and activity patterns in animal models and clinical investigations, as well as functional studies with gene knockouts and enzyme inhibitors, MMPs have been demonstrated to play a paramount role in many physiological and pathological processes in the brain. In particular, they have been shown to influence learning and memory processes, as well as major neuropsychiatric disorders such as schizophrenia, various kinds of addiction, epilepsy, fragile X syndrome, and depression. A possible link connecting all those conditions is either physiological or aberrant synaptic plasticity where some MMPs, e.g., MMP-9, have been demonstrated to contribute to the structural and functional reorganization of excitatory synapses that are located on dendritic spines. Another common theme linking the aforementioned pathological conditions is neuroinflammation and MMPs have also been shown to be important mediators of immune responses.

Current progress in searching for clinically useful biomarkers of blood-brain barrier damage following cerebral ischemia

Ischemic stroke is a leading cause of death and disability. Fear of intracranial hemorrhage (ICH) has been the primary reason for withholding tissue plasminogen activator (tPA) and thrombectomy, the only two widely accepted treatments for ischemic stroke. Thrombolysis treatment is only allowed in a very narrow time window (within 4.5–6 h). However, so far, other than the time window guideline, there is no reliable indicator available in the clinic to predict ICH before thrombolysis treatment. Recently, extensive research efforts have been devoted to the development of reliable indicators to predict ICH and safely guide the thrombolysis treatment. Accumulating evidence suggests that ischemic brain regions with a compromised blood–brain barrier (BBB) before tPA treatment develop ICH at the later time during thrombolytic reperfusion. Assessing BBB damage before thrombolysis could potentially help predict the risk of ICH after thrombolysis. This article reviews the literature reports on BBB damage biomarkers that have been developed in recent years, including biochemical markers such as BBB structural proteins, circulating brain microvascular endothelial cells, plasma albumin, and brain parenchyma proteins, as well as image markers such as magnetic resonance imaging assessment for BBB damage.

Multiplex Matrix Metalloproteinases Analysis in the Cerebrospinal Fluid Reveals Potential Specific Patterns in Multiple Sclerosis Patients

Background: Matrix metalloproteinases (MMPs) are pleiotropic enzymes involved in extracellular protein degradation and turnover. MMPs are implicated in the pathogenesis of many neurological diseases, including multiple sclerosis (MS).

Objective: To search the level of MMPs in the cerebrospinal fluid (CSF) of MS patients and detect possible disease-specific patterns.

Methods: CSF samples from 32 MS patients and, from 15 control subjects with other inflammatory neurological diseases (OIND) were analyzed. The Bio-Plex Pro Human MMP 9-Plex Panel (Bio-Rad) was used for the quantification of MMP-1, MMP-2, MMP-3, MMP-7, MMP-8, MMP-9, MMP-10, MMP-12, and MMP-13.

Results: CSF MMP-1 and MMP-12 levels were significantly reduced in MS as compared with OIND. In MS patients' CSF: (i) MMP-1 levels were significantly higher in women vs. men; (ii) MMP-10 concentrations were higher in patients with CSF-restricted IgG oligoclonal bands, and (iii) MMP-7 levels were increased in patients with longer disease duration. In the OIND group MMP-7 and MMP-12 levels significantly and directly correlated with age.

Conclusions: Our study contributes to investigating the role of MMPs in MS, with regard to CSF immunological features and disease duration. Sex-specific differences were also detected in MMPs CSF levels.

Acupuncture Decreases Matrix Metalloproteinase-2 Activity in Patients with Migraine

Objective

To evaluate the effect of acupuncture on the serum matrix metalloproteinase-2 (MMP-2) level and activity in patients with migraine.

Methods

After baseline testing, eligible patients with migraine according to the criteria of the International Headache Society who volunteered to join the study were included (n=27). The patients received 10 sessions of acupuncture treatment. The points selected were bilateral ST8, ST44, LI4, LI11, LIV3, SP6, GB1, GB14, GB20, GV14, GV20, Yintang, Taiyang and ear Shenmen. Pain was measured using a visual analogue scale (VAS). Short form-36 (SF-36) was used to determine their quality of life. Blood samples were taken before treatment and after the first and last sessions of acupuncture for measurement of MMP-2 concentration and activity.

Results

The mean VAS was 85.5±16.6 before acupuncture and was significantly decreased to 39.8±20.6 after 10 sessions of acupuncture (p<0.0001). There was a significant increase in all SF-36 scores after acupuncture compared with values before treatment (p<0.0001). No significant differences were found in MMP-2 concentrations before treatment and after the first and last sessions (p>0.05). However, there were significant changes in MMP-2 activity (p<0.0001).

Conclusions

The results of this study showed a clinically relevant decrease in MMP-2 activity in patients with migraine treated with acupuncture. The mechanism underlying the effect of acupuncture in alleviating pain may be associated with a decrease in MMP-2 activity.

Pathophysiology of Trans-Synaptic Adhesion Molecules: Implications for Epilepsy

Chemical synapses are specialized interfaces between neurons in the brain that transmit and modulate information, thereby integrating cells into multiplicity of interacting neural circuits. Cell adhesion molecules (CAMs) might form trans-synaptic complexes that are crucial for the appropriate identification of synaptic partners and further for the establishment, properties, and dynamics of synapses. When affected, trans-synaptic adhesion mechanisms play a role in synaptopathies in a variety of neuropsychiatric disorders including epilepsy. This review recapitulates current understanding of trans-synaptic interactions in pathophysiology of interneuronal connections. In particular, we discuss here the possible implications of trans-synaptic adhesion dysfunction for epilepsy.

Matrix Metalloproteinases and Tissue Inhibitor of Metalloproteinases in Inflammation and Fibrosis of Skeletal Muscles

In skeletal muscles, levels and activity of Matrix MetalloProteinases (MMPs) and Tissue Inhibitors of MetalloProteinases (TIMPs) have been involved in myoblast migration, fusion and various physiological and pathological remodeling situations including neuromuscular diseases. This has opened perspectives for the use of MMPs' overexpression to improve the efficiency of cell therapy in muscular dystrophies and resolve fibrosis. Alternatively, inhibition of individual MMPs in animal models of muscular dystrophies has provided evidence of beneficial, dual or adverse effects on muscle morphology or function. We review here the role played by MMPs/TIMPs in skeletal muscle inflammation and fibrosis, two major hurdles that limit the success of cell and gene therapy. We report and analyze the consequences of genetic or pharmacological modulation of MMP levels on the inflammation of skeletal muscles and their repair in light of experimental findings. We further discuss how the interplay between MMPs/TIMPs levels, cytokines/chemokines, growth factors and permanent low-grade inflammation favor cellular and molecular modifications resulting in fibrosis.

Pathophysiology and immunological profile of myasthenia gravis and its subgroups

Myasthenia gravis (MG) is an autoimmune antibody-mediated disease characterized by muscle weakness and fatigability. It is believed that the initial steps triggering humoral immunity in MG take place inside thymic tissue and thymoma. The immune response against one or several epitopes expressed on thymic tissue cells spills over to neuromuscular junction components sharing the same epitope causing humoral autoimmunity and antibody production. The main cause of MG is acetylcholine receptor antibodies. However, many other neuromuscular junction membrane protein targets, intracellular and extracellular proteins are suggested to participate in MG pathophysiology. MG should be divided into subgroups based on clinical presentation and immunology. This includes onset age, clinical characteristics, thymic pathology and antibody profile. The immunological profile of these subgroups is determined by the antibodies present.

Intracranial Arterial Dolichoectasia

An increased diameter (ectasis) and/or long and tortuous course (dolichosis) of at least one cerebral artery define intracranial arterial dolichoectasia (IADE). IADE could be detected incidentally or may give rise to an array of neurological complications including ischemic stroke, intracranial hemorrhage, or compression of surrounding neural structures. The basilar artery is preferentially affected and has been studied in more detail, mainly due to the presence of accepted diagnostic criteria proposed by Smoker and colleagues in 1986 (1). Criteria for the diagnoses of dolichoectasia in other cerebral arteries have been suggested. However, they lack validation across studies. The prevalence of IADE is approximately 0.08–6.5% in the general population, while in patients with stroke, the prevalence ranges from 3 to 17%. Variations among case series depend on the characteristics of the studied population, diagnostic tests used, and diagnostic criteria applied. In rare instances, an underlying hereditary condition, connective tissue disorder, or infection predispose to the development of IADE. However, most cases are sporadic and associated with traditional vascular risk factors including advanced age, male gender, and arterial hypertension. The link between this dilative arteriopathy and other vascular abnormalities, such as abdominal aortic aneurysm, coronary artery ectasia, and cerebral small vessel disease, suggests the underlying diffuse vascular process. Further understanding is needed on the physiopathology of IADE and how to prevent its progression and clinical complications.

Matrix Metalloproteinases, Neural Extracellular Matrix, and Central Nervous System Pathology

The functionality and stability of the central nervous system (CNS) pabulum, called neural extracellular matrix (nECM), is paramount for the maintenance of a healthy network. The loosening or the damage of the scaffold disrupts synaptic transmission with the consequent imbalance of the neurotransmitters, reactive cells invasion, astrocytosis, new matrix deposition, digestion of the previous structure and ultimately, maladaptive plasticity with the loss of neuronal viability. nECM is constantly affected by CNS disorders, particularly in chronic modifying such as neurodegenerative disease, or in acute/subacute with chronic sequelae, like cerebrovascular and inflammatory pathology. Matrix metalloproteinases (MMPs) are the main interfering agent of nECM, guiding the balance of degradation and new deposition of proteins such as proteoglycans and glycoproteins, or glycosaminoglycans, such as hyaluronic acid. Activation of these enzymes is modulated by their physiologic inhibitors, the tissue inhibitors of MMPs or via other proteases inhibitors, as well as genetic or epigenetic up- or downregulation through molecular interaction or receptor activation. The appropriate understanding of the pathways underlying nECM modifications in CNS pathology is probably one of the pivotal future directions to identify the healthy brain network and subsequently design new therapies to interfere with the progression of the CNS disease and eventually find appropriate therapies.

Biocompatibility of primers and an adhesive used for implant-retained maxillofacial prostheses: An in vitro analysis

STATEMENT OF PROBLEM

Implant-retained maxillofacial prostheses should be biocompatible, regardless of the primers and adhesives used to bond the acrylic resin and facial silicone. The authors are unaware of any study evaluating the influence of these primers and adhesives on the biocompatibility of maxillofacial prostheses.

PURPOSE

The purpose of this in vitro study was to evaluate the cytotoxic effect of primers and an adhesive used to bond acrylic resin and facial silicone during the fabrication of implant-retained maxillofacial prostheses.

MATERIAL AND METHODS

Twenty-eight circular specimens made of resin and silicone were fabricated, either bonded or nonbonded with primer and adhesive. The specimens were divided into 7 groups: resin; silicone; resin+silastic medical adhesive type A+silicone; resin+DC 1205 primer silicone; resin+Sofreliner primer+silicone; resin+DC 1205 primer+silastic medical adhesive type A+silicone; and resin+Sofreliner primer+silastic medical adhesive type A+silicone. Eluates of the materials tested were prepared by setting 4 specimens of each experimental group in Falcon tubes with medium and incubating at 37°C for 24 hours. The eluate cytotoxicity was evaluated by an assay of survival/proliferation ((3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide [MTT] test) in cultures of human keratinocytes. The levels of IL1, IL6, TNFα, and the chemokine MIP-1α were evaluated by enzyme-linked immunosorbent assay. The mRNA expressions for MMP-9, TGF-β, and collagen type IV were analyzed by the real time polymerase chain reaction. Data were submitted to analysis of variance with Bonferroni post hoc tests (α=.05).

RESULTS

An increased cell proliferation was observed for the RAS group, with statistically significant differences (P<.001) compared with the unstimulated group. The RDCpS group showed the highest IL6 concentration values (P<.001). No significant statistical difference was found in the relative quantification of mRNA for collagen type IV, MMP9, or TGFβ between the groups (P>.05).

CONCLUSIONS

The RAS group showed the highest cell proliferation percentage, while the RDCpS group exhibited the highest IL6 concentration values. No detectable levels of IL1β, TNF α, or CCL3/MIP1α were observed. The tested materials showed no toxic effects on the HaCaT cell line.

The role of MMP genes in recurrent depressive disorders and cognitive functions

OBJECTIVE

Among the 28 metalloproteinases described so far, 23 can be found in the human organism, but only few are expressed in the human brain. The main objective of this study was to analyse the relationship between MMP-2, MMP-9 and TIMP-2 gene expression and cognitive performance.

METHODS

The study comprised 234 subjects: patients suffering from recurrent depressive disorder (rDD, n=139) and healthy subjects (HS, n=95). The cognitive function assessment was carried out with the help of the following tests: Trail Making Test, The Stroop Test, Verbal Fluency Test and Auditory Verbal Learning Test. Gene expression on the mRNA and protein level was evaluated for MMP-2, MMP-9 and TIMP-2 in both groups using RNA extraction, reverse transcription and enzyme-linked immunosorbent assay.

RESULTS

Both mRNA and protein expression levels of all the genes were significantly lower in rDD subjects as compared with HS. Having analysed the entire experimental group (N=234), significant interrelations were found between the expression of the analysed genes and the results of the tests used to measure cognitive functions. Increased expression on both the mRNA and the protein level was associated in each case with better performance of all the tests conducted. After carrying out a separate analysis on the people from the rDD group and the HS group, similar dependencies were still observed.

CONCLUSIONS

The results of our study show decreased expression of MMP-2, MMP-9 and TIMP-2 genes on both mRNA and protein levels in depression. Elevated expression of MMP-2, MMP-9, TIMP-2 positively affects cognitive efficiency: working memory, executive functions, attention functions, direct and delayed auditory-verbal memory, the effectiveness of learning processes and verbal fluency. The study highlights the important role of peripheral matrix metalloproteinases genes in depression and cognitive functions.

Interplay between Matrix Metalloproteinase-9, Matrix Metalloproteinase-2, and Interleukins in Multiple Sclerosis Patients

Matrix Metalloproteases (MMPs) and cytokines have been involved in the pathogenesis of multiple sclerosis (MS). However, no studies have still explored the possible associations between the two families of molecules. The present study aimed to evaluate the contribution of active MMP-9, active MMP-2, interleukin- (IL-) 17, IL-18, IL-23, and monocyte chemotactic proteins-3 to the pathogenesis of MS and the possible interconnections between MMPs and cytokines. The proteins were determined in the serum and cerebrospinal fluid (CSF) of 89 MS patients and 92 other neurological disorders (OND) controls. Serum active MMP-9 was increased in MS patients and OND controls compared to healthy subjects (p < 0.001 and p < 0.01, resp.), whereas active MMP-2 and ILs did not change. CSF MMP-9, but not MMP-2 or ILs, was selectively elevated in MS compared to OND (p < 0.01). Regarding the MMPs and cytokines intercorrelations, we found a significant association between CSF active MMP-2 and IL-18 (r = 0.3, p < 0.05), while MMP-9 did not show any associations with the cytokines examined. Collectively, our results suggest that active MMP-9, but not ILs, might be a surrogate marker for MS. In addition, interleukins and MMPs might synergistically cooperate in MS, indicating them as potential partners in the disease process.

Evaluation of serum matrix metalloproteinase-3 as a biomarker for diagnosis of epilepsy

OBJECTIVE

Reliable molecular biomarkers for epilepsy have yet to be identified. The present study aims to evaluate the utility of serum metalloproteinase-3 as a diagnostic biomarker for epilepsy.

METHODS

Serum MMP-3 levels were assessed in 227 individuals with epilepsy and 97 healthy control subjects. Individuals in the control group had no complaints or signs of any neurological disorder for at least 12months before serum collection. The Luminex FLEXMAP 3D assay was used to determine serum MMP-3 levels.

RESULTS

Compared with controls, subjects with epilepsy had significantly lower serum MMP-3 concentrations (p<0.05). Serum MMP-3 concentrations were significantly higher in males than in females (p<0.001). Furthermore, Serum MMP-3 concentrations were strongly correlated with age in both epileptic and control groups. For these reasons, ROC curve analyses were performed in age-matched and gender matched groups. In the population aged 20-40years, when cut-off values of 23.87ng/ml and 12.31ng/ml were chosen for MMP-3 in males and females respectively, the sensitivity and specificity for patients with epilepsy versus controls were 72.22% and 76.67% for males, and 45% and 94.12% for females. And when cut-off MMP-3 concentrations of 20.70ng/ml and 10.92ng/ml were chosen for the ≥40years age group, the sensitivity and specificity to distinguish between epileptic and control subjects were 85.71% and 47.62% versus 85.62% and 100% for male and female groups, respectively.

CONCLUSIONS

MMP-3 is reduced in epilepsy patients compared to healthy controls. The potential of MMP-3 as an epilepsy biomarker is limited to certain age brackets and depends on the gender.

Analysis of MMP2-1306C/T and TIMP2G-418C polymorphisms with relapsing remitting multiple sclerosis

AIMS

Multiple sclerosis (MS) is an autoimmune, inflammatory disease characterized by loss of myelin forming oligodendrocytes and changes in the blood-brain barrier. Matrix metalloproteinase (MMP) -2 and -9 are known to cause disruption of the blood-brain barrier, remodeling of the basal lamina, regeneration of axons, and remyelination in MS. The imbalance between MMPs and tissue inhibitor metalloproteinases (TIMPs) may lead to the emergence of pathological processes such as MS. The roles of MMP2-1306 C/T and TIMP2-418 G/C genetic variants in MS have not been studied before. We aimed to investigate whether MMP2-1306C/T and TIMP2-418 G/C gene variants are risk factors for patients with relapsing remitting multiple sclerosis (RRMS).

METHODS

The study included 102 RRMS and 102 healthy controls. Genomic DNA was extracted from peripheral leukocytes from ethylenediaminetetraacetic acid anticoagulated blood. Genotyping of the MMP2-1306C/T and TIMP2G-418C polymorphisms was performed using real-time PCR.

RESULTS

There were significant differences in terms of distribution of genotype (MMP2-1306- CT, TT) and T allele frequency between the patients with RRMS and the control group (p<0.0001; p<0.0001). The groups were not different in terms of TIMP2G-418C polymorphisms.

CONCLUSIONS

In the RRMS group, the genotype and allele frequencies of MMP2-1306C/T polymorphism showed significant differences from the controls. These results indicate that MMP2 might play a role in the pathogenesis of MS even during the inflammation stage.

Modulation of Matrix Metalloproteinases Activity in the Ventral Horn of the Spinal Cord Re-stores Neuroglial Synaptic Homeostasis and Neurotrophic Support following Peripheral Nerve Injury

Modulation of extracellular matrix (ECM) remodeling after peripheral nerve injury (PNI) could represent a valid therapeutic strategy to prevent maladaptive synaptic plasticity in central nervous system (CNS). Inhibition of matrix metalloproteinases (MMPs) and maintaining a neurotrophic support could represent two approaches to prevent or reduce the maladaptive plastic changes in the ventral horn of spinal cord following PNI. The purpose of our study was to analyze changes in the ventral horn produced by gliopathy determined by the suffering of motor neurons following spared nerve injury (SNI) of the sciatic nerve and how the intrathecal (i.t.) administration of GM6001 (a MMPs inhibitor) or the NGF mimetic peptide BB14 modulate these events. Immunohistochemical analysis of spinal cord sections revealed that motor neuron disease following SNI was associated with increased microglial (Iba1) and astrocytic (GFAP) response in the ventral horn of the spinal cord, indicative of reactive gliosis. These changes were paralleled by decreased glial aminoacid transporters (glutamate GLT1 and glycine GlyT1), increased levels of the neuronal glutamate transporter EAAC1, and a net increase of the Glutamate/GABA ratio, as measured by HPLC analysis. These molecular changes correlated to a significant reduction of mature NGF levels in the ventral horn. Continuous i.t. infusion of both GM6001 and BB14 reduced reactive astrogliosis, recovered the expression of neuronal and glial transporters, lowering the Glutamate/GABA ratio. Inhibition of MMPs by GM6001 significantly increased mature NGF levels, but it was absolutely ineffective in modifying the reactivity of microglia cells. Therefore, MMPs inhibition, although supplies neurotrophic support to ECM components and restores neuro-glial transporters expression, differently modulates astrocytic and microglial response after PNI.

Altered Serum Levels of Matrix Metalloproteinase-2, -9 in Response to Electroconvulsive Therapy for Mood Disorders

BACKGROUND

Inflammatory processes could underlie mood disorders. Matrix metalloproteinases (MMPs) and tissue inhibitors of MMPs (TIMP) are inflammation-related molecules. The current study sought an association between mood disorders and systemic levels of MMPs and TIMPs.

METHODS

Serum was obtained from patients with mood disorders (n=21) and patients with schizophrenia (n=13) scheduled to undergo electroconvulsive therapy. Serum was also obtained from healthy controls (n=40). Clinical symptoms were assessed by the Hamilton Rating Score for Depression and the Brief Psychiatric Rating Scale. Serum levels of MMPs and TIMPs were quantified by ELISA.

RESULTS

The serum levels of MMP-2 in mood disorder patients, but not in schizophrenia patients, prior to the first electroconvulsive therapy session (baseline) was significantly lower than that of healthy controls. At baseline, levels of MMP-9 and TIMP-2, -1 were not different between patients with mood disorder and schizophrenia and healthy controls. After a course of electroconvulsive therapy, MMP-2 levels were significantly increased in mood disorder patients, but MMP-9 levels were significantly decreased in both mood disorder and schizophrenia patients. In mood disorder patients, there was a significant negative correlation between depressive symptoms and serum levels of MMP-2 and a positive correlation between depressive symptoms and MMP-9. In addition, alterations of serum levels of MMP-2 and MMP-9 were significantly correlated each other and were associated with certain depressive symptoms.

CONCLUSION

A change in inflammatory homeostasis, as indicated by MMP-2 and MMP-9, could be related to mood disorders, and these markers appear to be sensitive to electroconvulsive therapy.

Towards a blood-based diagnostic panel for bipolar disorder

BACKGROUND

Bipolar disorder (BD) is a costly, devastating and life shortening mental disorder that is often misdiagnosed, especially on initial presentation. Misdiagnosis frequently results in ineffective treatment. We investigated the utility of a biomarker panel as a diagnostic test for BD.

METHODS AND FINDINGS

We performed a meta-analysis of eight case-control studies to define a diagnostic biomarker panel for BD. After validating the panel on established BD patients, we applied it to undiagnosed BD patients. We analysed 249 BD, 122 pre-diagnostic BD, 75 pre-diagnostic schizophrenia and 90 first onset major depression disorder (MDD) patients and 371 controls. The biomarker panel was identified using ten-fold cross-validation with lasso regression applied to the 87 analytes available across the meta-analysis studies. We identified 20 protein analytes with excellent predictive performance [area under the curve (AUC)⩾0.90]. Importantly, the panel had a good predictive performance (AUC 0.84) to differentiate 12 misdiagnosed BD patients from 90 first onset MDD patients, and a fair to good predictive performance (AUC 0.79) to differentiate between 110 pre-diagnostic BD patients and 184 controls. We also demonstrated the disease specificity of the panel.

CONCLUSIONS

An early and accurate diagnosis has the potential to delay or even prevent the onset of BD. This study demonstrates the potential utility of a biomarker panel as a diagnostic test for BD.

Two classes of matrix metalloproteinases reciprocally regulate synaptogenesis

Synaptogenesis requires orchestrated intercellular communication between synaptic partners, with trans-synaptic signals necessarily traversing the extracellular synaptomatrix separating presynaptic and postsynaptic cells. Extracellular matrix metalloproteinases (Mmps) regulated by secreted tissue inhibitors of metalloproteinases (Timps), cleave secreted and membrane-associated targets to sculpt the extracellular environment and modulate intercellular signaling. Here, we test the roles of Mmp at the neuromuscular junction (NMJ) model synapse in the reductionist Drosophila system, which contains just two Mmps (secreted Mmp1 and GPI-anchored Mmp2) and one secreted Timp. We found that all three matrix metalloproteome components co-dependently localize in the synaptomatrix and show that both Mmp1 and Mmp2 independently restrict synapse morphogenesis and functional differentiation. Surprisingly, either dual knockdown or simultaneous inhibition of the two Mmp classes together restores normal synapse development, identifying a reciprocal suppression mechanism. The two Mmp classes co-regulate a Wnt trans-synaptic signaling pathway modulating structural and functional synaptogenesis, including the GPI-anchored heparan sulfate proteoglycan (HSPG) Wnt co-receptor Dally-like protein (Dlp), cognate receptor Frizzled-2 (Frz2) and Wingless (Wg) ligand. Loss of either Mmp1 or Mmp2 reciprocally misregulates Dlp at the synapse, with normal signaling restored by co-removal of both Mmp classes. Correcting Wnt co-receptor Dlp levels in both Mmp mutants prevents structural and functional synaptogenic defects. Taken together, these results identify an Mmp mechanism that fine-tunes HSPG co-receptor function to modulate Wnt signaling to coordinate synapse structural and functional development.

TIMP-1 resistant matrix metalloproteinase-9 is the predominant serum active isoform associated with MRI activity in patients with multiple sclerosis

BACKGROUND

The activity of matrix metalloproteinase-9 (MMP-9) depends on two isoforms, an 82 kDa active MMP-9 modulated by its specific tissue inhibitor (TIMP-1), and a 65 kDa TIMP-1 resistant active MMP-9. The relevance of these two enzymatic isoforms in multiple sclerosis (MS) is still unknown.

OBJECTIVE

To investigate the contribution of the TIMP-1 modulated and resistant active MMP-9 isoforms to MS pathogenesis.

METHODS

We measured the serum levels of the 82 kDa and TIMP-1 resistant active MMP-9 isoforms by activity assay systems in 86 relapsing-remitting MS (RRMS) patients, categorized according to clinical and magnetic resonance imaging (MRI) evidence of disease activity, and in 70 inflammatory (OIND) and 69 non-inflammatory (NIND) controls.

RESULTS

Serum levels of TIMP-1 resistant MMP-9 were more elevated in MS patients than in OIND and NIND (p < 0.05, p < 0.02, respectively). Conversely, 82 kDa active MMP-9 was higher in NIND than in the OIND and MS patients (p < 0.01 and p < 0.00001, respectively). MRI-active patients had higher levels of TIMP-1 resistant MMP-9 and 82 kDa active MMP-9, than did those with MRI inactive MS (p < 0.01 and p < 0.05, respectively).

CONCLUSION

Our findings suggested that the TIMP-1 resistant MMP-9 seem to be the predominantly active isoform contributing to MS disease activity.

Astrocyte mediated MMP-9 activation in the synapse dysfunction: An implication in Alzheimer disease

Alzheimer's disease (AD) is a progressive neurodegenerative disorder that occurs due to spasms of the neurons, resulting in loss of memory and behavioral changes. In particular, synaptic loss has been described as an early event in the pathogenesis of AD. The increasing evidences have suggested the role of many matrix metalloproteinase (MMPs) in central nervous system (CNS) pathology. Many studies showed that MMPs enzymes are important for the pathophysiological process during Alzheimer's disease (AD). It is usually believed that the synaptic dysfunction and synapse loss contribute to the cognitive deficits of patients with AD. Cerebrovascular events such as blood-brain barrier (BBB) disruption lead to neuronal damage as well as neuroinflammation. BBB dysfunctions are observed at an early post injury time point, and are associated with activation of proteases, such as MMPs especially MMP-9 which is actively engage in a neuronal injury in the most of the neurodegenerative disorders. BBB opening is accompanied by astrocytic activation, BBB injury and dysregulation of cerebral blood flow. Activated MMPs disrupt neurovascular unit (NVU) which may starve the neurons and affect the synapse function by altering synaptic plasticity and ultimately lead to cognitive decline. However, how MMPs implicated in synaptic dysfunction what are the mechanism associated with this disparity needs to discuss for better understanding the role of MMP-9 in pathogenesis of AD. In this review, we focused on the role of astrocytes and MMP-9 in synaptic dysfunction. We also, underlined possible pharmacological strategies for drug development that might offer more insight into the pathogenesis of cerebrovascular disease such as stroke and Vascular dementia.

Matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in amyotrophic lateral sclerosis (ALS)

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases, responsible for the integrity of the basement membrane (BM) via degradation of extracellular matrix and BM components. These enzymes are presented in central and peripheral nervous system. They are considered to be involved in the pathogenesis of several neurological diseases, including amyotrophic lateral sclerosis (ALS). ALS is a motor neuron disease, leading to muscle atrophy, paralysis and death within 3–5 years from diagnosis. Currently, there is no treatment that can substantially prolong life of ALS patients. Despite the fact that MMPs are not specific for ALS, there is also strong evidence that these enzymes are involved in the pathology of ALS. MMPs are able to exert direct neurotoxic effects, or may cause cell death by degrading matrix proteins. The objective of this paper is to provide an updated and comprehensive review concerning the role of MMPs and their tissue inhibitors (TIMPs) in the pathology of ALS with an emphasis on the significance of MMP-2 and MMP-9 as well as their tissue inhibitors as potential biomarkers of ALS. Numerous hypotheses have been proposed regarding the role of selected MMPs and TIMPs in ALS pathogenesis. Moreover, selective MMPs’ inhibitors might be potential targets for therapeutic strategies for patients with ALS. However, future investigations are necessary before some of those non-specific for ALS enzymes could finally be used as biomarkers of this disease.

The significance of matrix metalloproteinase (MMP)-2 and MMP-9 in the ischemic stroke

There is a continuous urgent need to explore the pathogenesis and biochemical changes within the infarcted area during acute ischemic stroke (IS). Matrix metalloproteinases (MMPs), prevailing extracellular endopeptideses, can digest proteins located extracellulary, e.g. collagen, proteoglycans, elastin or fibronectin. Among MMPs, gelatinases (MMP-2 and MMP-9) are the most investigated enzymes. Gelatinases possess the ability to active numerous pro-inflammatory agents as chemokine CXCL-8, interleukin 1β or tumor necrosis factor α. Moreover, due to digestion of collagen type IV (the component of basal membranes) and tight junction proteins (TJPs) they facilitate to cross the endothelium by leukocytes. Due to the significant role of gelatinases during brain ischemia, their selective inhibition seems to be an interesting kind of treatment of acute stroke. The synthetic inhibitors of gelatineses decrease the infarct volume in animal models of IS. In clinical practice statins, the lipid-lowering drugs possess the ability to inhibit the activity of MMP-9 during acute IS. This review briefly provides the most important information about the involvement of MMP-2 and MMP-9 in the pathogenesis of brain ischemia.

Potential serum biomarkers in the pathophysiological processes of stroke

Stroke is a leading cause of death and serious long-term disability. Ischemic stroke is the major subtype of stroke. Currently, its diagnosis is mainly dependent upon clinical symptoms and neuroimaging techniques. Despite these clinical and imaging modalities, often strokes are not recognized after initial onset. As early intervention of medical or surgical therapy is often associated with improved outcomes, there is an urgent need to improve the speed and accuracy of stroke diagnosis. Stroke is a complex pathophysiological process involving; energy failure, imbalance of ion homeostasis, acidosis, intracellular calcium overload, neuronal excitotoxicity, free radical-mediated lipid oxidation, inflammatory cell infiltration, and glial cell activation. These events ultimately lead to neuronal apoptotic cell death or necrosis. In this review, we have summarized the serum biomarkers according to the pathophysiological processes of stroke, which have been intensively studied in clinical trials of stroke over the past five years, and also used Medline's 'related article' option to identify further articles. We focused on the potential biomarkers pertaining to vascular injury, metabolic changes, oxidative injury, and inflammation, and newly studied biomarkers, and discussed how these biomarkers could be used for the diagnosis or determining the prognosis of stroke.

Inflammation markers in multiple sclerosis: CXCL16 reflects and may also predict disease activity

Background

Serum markers of inflammation are candidate biomarkers in multiple sclerosis (MS). ω-3 fatty acids are suggested to have anti-inflammatory properties that might be beneficial in MS. We aimed to explore the relationship between serum levels of inflammation markers and MRI activity in patients with relapsing remitting MS, as well as the effect of ω-3 fatty acids on these markers.

Methods

We performed a prospective cohort study in 85 relapsing remitting MS patients who participated in a randomized clinical trial of ω-3 fatty acids versus placebo (the OFAMS study). During a period of 24 months 12 repeated magnetic resonance imaging (MRI) scans and nine serum samples were obtained. We measured 10 inflammation markers, including general down-stream markers of inflammation, specific markers of up-stream inflammatory pathways, endothelial action, and matrix regulation.

Results

After Bonferroni correction, increasing serum levels of CXCL16 and osteoprotegerin were associated with low odds ratio for simultaneous MRI activity, whereas a positive association was observed for matrix metalloproteinase (MMP) 9. CXCL16 were also associated with low MRI activity the next month, but this was not significant after Bonferroni correction. In agreement with previously reported MRI and clinical results, ω-3 fatty acid treatment did not induce any change in the inflammation markers.

Conclusions

Serum levels of CXCL16, MMP-9, and osteoprotegerin reflect disease activity in MS, but are not affected by ω-3 fatty acid treatment. CXCL16 could be a novel biomarker and potential predictor of disease activity in MS.

Is MS an inflammatory or primary degenerative disease?

Multiple sclerosis (MS) is characterized by multiple areas of inflammation, demyelination and neurodegeneration. Multiple molecular and cellular components mediate neuroinflammation in MS. They involve: adhesion molecules, chemokines, cytokines, matalloproteases and the following cells: CD4+ T cells, CD8+ T cells, B cells, microglia and macrophages. Infiltrating Th1 CD4+ T cells secrete proinflammatory cytokines. They stimulate the release of chemokines, expression of adhesion molecules and can be factors that cause damage to the myelin sheath and axons. Chemokines stimulate integrin activation, mediate leukocyte locomotion on endothelial cells and participate in transendothelial migration. CD8+ cells can directly damage axons. B cells are involved in the production of antibodies which can participate in demyelination. B cells can also function as antigen presenting cells and contribute to T cell activation. Neuroinflammation is not only present in relapsing-remitting MS, but also in the secondary and primary progressive forms of the disease. The association between inflammation consisting of T cells, B cells, plasma cells and macrophages and axonal injury exists in MS patients including the progressive forms of the disease. The above association does not exclude the possibility that neurodegeneration can exist independently from inflammation. Very little inflammation is seen in cortical MS plaques. Anti-inflammatory therapies with different mode of action change the course of MS. Anti-inflammatory and immunomodulatory treatments are beneficial in the early relapsing stage of MS, but these treatments are ineffective in secondary progressive and primary progressive MS. In the stage of progressive MS, inflammation becomes trapped behind a closed or repaired blood-brain barrier. In such a situation current immunomodulatory, immunosuppressive or anti-inflammatory treatments might not reach this inflammatory process to exert a beneficial effect.

α-Mangostin suppresses lipopolysaccharide-induced invasion by inhibiting matrix metalloproteinase-2/9 and increasing E-cadherin expression through extracellular signal-regulated kinase signaling in pancreatic cancer cells

Invasion and metastasis are major factors in the poor prognosis of pancreatic cancer, which remains one of the most aggressive and lethal diseases worldwide. α-mangostin, a major xanthone compound identified in the pericarp of mangosteen (Garcinia mangostana, Linn; GML), possesses unique biological activities, including antioxidant, antitumor and anti-inflammatory effects. Whether α-mangostin is able to inhibit the invasive ability of pancreatic cancer cells has not been elucidated. In the present study, α-mangostin was shown to inhibit the invasive ability of the pancreatic cancer cell lines MIAPaCa-2 and BxPC-3. The results showed that α-mangostin inhibited the growth of the pancreatic cancer cells in a dose- and time-dependent manner. At concentrations of <5 μM, α-mangostin had no significant effects on cytotoxicity, but significantly inhibited the invasion and migration of pancreatic cancer cells and the expression of matrix metalloproteinase (MMP)-2 and MMP-9, while increasing the expression of E-cadherin. The present data also showed that α-mangostin exerted an inhibitory effect on the phosphorylation of extracellular-signal-regulated kinase (ERK). Furthermore, the reduction of ERK phosphorylation by small interfering RNA (siRNA) potentiated the effect of α-mangostin. Taken together, the data suggest that α-mangostin inhibited the invasion and metastasis of pancreatic cancer cells by reducing MMP-2 and MMP-9 expression, increasing E-cadherin expression and suppressing the ERK signaling pathway. The present study suggests that α-mangostin may be a promising agent against pancreatic cancer.