MMPs/TIMPs imbalances in the peripheral blood and cerebrospinal fluid are associated with the pathogenesis of HIV-1-associated neurocognitive disorders.

HIV-1-associated neurocognitive disorders (HAND) continue to be a major concern in the infected population, despite the widespread use of combined antiretroviral therapy (cART). Growing evidence suggests that an imbalance between matrix metalloproteinases (MMPs) and endogenous tissue inhibitors of MMPs (TIMPs) contributes to the pathogenesis of HAND. In our present study, we examined protein levels and enzymatic activities of MMPs and TIMPs in both plasma and cerebrospinal fluid (CSF) samples from HIV-1 patients with or without HAND and HIV-1-negative controls. Imbalances between MMPs and TIMPs with distinct patterns were revealed in both the peripheral blood and CSF of HIV-1 patients, especially those with HAND. In the peripheral blood, the protein levels of MMP-2, MMP-9, TIMP-1, TIMP-2, and the enzymatic activities of MMP-2 and MMP-9 were increased in HIV-1 patients with or without HAND when compared with HIV-1-negative controls. The enzymatic activity of MMP-2, but not MMP-9, was further increased in plasma samples of HAND patients than that of HIV-1 patients without HAND. Notably, the ratio of MMP-2/TIMP-2 in plasma was significantly increased in HAND patients, not in patients without HAND. In the CSF, MMP-2 activity was increased, but the ratio of MMP-2/TIMP-2 was not altered. De novo induction and activation of MMP-9 in the CSF of HAND patients was particularly prominent. The imbalances between MMPs and TIMPs in the blood and CSF were related to the altered profiles of inflammatory cytokines/chemokines and monocyte activation in these individuals. In addition, plasma from HIV-1 patients directly induced integrity disruption of an in vitro blood-brain barrier (BBB) model, leading to increased BBB permeability and robust transmigration of monocytes/macrophages. These results indicate that imbalances between MMPs and TIMPs are involved in BBB disruption and are implicated in the pathogenesis of neurological disorders such as HAND in HIV-1 patients.

Monocyte and microglial activation in patients with mood-stabilized bipolar disorder.

BACKGROUND: Bipolar disorder is associated with medical comorbidities that have been linked to systemic inflammatory mechanisms. There is, however, limited evidence supporting a role of neuroinflammation in bipolar disorder. Here we tested whether microglial activation and associated tissue remodelling processes are related to bipolar disorder by analyzing markers in cerebrospinal fluid (CSF) and serum from patients and healthy controls. METHODS: Serum was sampled from euthymic patients with bipolar disorder and healthy controls, and CSF was sampled from a large subset of these individuals. The levels of monocyte chemoattractant protein-1 (MCP-1), YKL-40, soluble cluster of differentiation 14 (sCD14), tissue inhibitor of metalloproteinases-1 (TIMP-1) and tissue inhibitor of metalloproteinases-2 (TIMP-2), were measured, and we adjusted comparisons between patients and controls for confounding factors. RESULTS: We obtained serum samples from 221 patients and 112 controls and CSF samples from 125 patients and 87 controls. We found increased CSF levels of MCP-1 and YKL-40 and increased serum levels of sCD14 and YKL-40 in patients compared with controls; these differences remained after controlling for confounding factors, such as age, sex, smoking, blood-CSF barrier function, acute-phase proteins and body mass index. The CSF levels of MCP-1 and YKL-40 correlated with the serum levels, whereas the differences between patients and controls in CSF levels of MCP-1 and YKL-40 were independent of serum levels. LIMITATIONS: The cross-sectional study design precludes conclusions about causality. CONCLUSION: Our results suggest that both neuroinflammatory and systemic inflammatory processes are involved in the pathophysiology of bipolar disorder. Importantly, markers of immunological processes in the brain were independent of peripheral immunological activity.

Matrix metalloproteinases and their tissue inhibitors in serum and cerebrospinal fluid of patients with amyotrophic lateral sclerosis.

BACKGROUND AND PURPOSE: Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of motor neuron degeneration in amyotrophic lateral sclerosis (ALS). We investigated the expression of MMPs and tissue inhibitors of matrix metalloproteinases (TIMPs) in serum and cerebrospinal fluid (CSF) correlating the results with age, disease duration and the clinical course. METHODS: The material consisted of 30 ALS patients and 15 age-matched healthy controls. ELISA method to determine the expression of MT-MMP-1, MMP-2, MMP-9, TIMP-1 and TIMP-2 in serum and CSF was used. MMP-2 and MMP-9 by zymography was also tested. RESULTS: In serum MT-MMP-1, MMP-2, MMP-9 and TIMP-1 expression was increased, especially in mild ALS cases. TIMP-2 values were normal. In CSF MT-MMP-1, MMP-2 and TIMP-1 level was either increased or normal, that of MMP-9 was decreased. TIMP-2 did not change. No correlation of MMPs and TIMP-1 expression in serum and CSF and the age of the patients was found. A correlation was observed between MMPs and TIMPs and disease duration. CONCLUSIONS: Increased level of MMPs and TIMP-1 of ALS patients may reflect the degeneration process of motor neurons and skeletal muscles and/or is associated with tissues remodeling. The low level of MMP-9 in CSF may result from impaired balance between MMP-9 and TIMP-1 and/or its increased intrathecal degradation and physical clearance. Although the role of changed MMPs/TIMPs level in the pathogenesis of ALS is not clear their analysis in serum may be used as prognostic factor and a potential marker for monitoring treatment effects.

Potential relevance of cerebrospinal fluid and serum levels and intrathecal synthesis of active matrix metalloproteinase-2 (MMP-2) as markers of disease remission in patients with multiple sclerosis.

BACKGROUND: Little is known about the involvement of matrix metalloproteinase-2 (MMP-2) and its tissue inhibitor TIMP-2 in multiple sclerosis (MS). OBJECTIVE: To elucidate the actual implication of MMP-2 and TIMP-2 in MS. METHODS: Cerebrospinal fluid (CSF) and serum levels of active MMP-2 and TIMP-2 were measured by activity assay system and ELISA, respectively, in 67 patients with relapsing-remitting MS (RRMS), categorized according clinical and magnetic resonance imaging (MRI), and in 129 controls. RESULTS: Cerebrospinal fluid and serum active MMP-2/TIMP-2 ratio mean values and an intrathecal active MMP-2 production were more increased in RRMS than in non-inflammatory conditions (P < 0.001, P < 0.05, and P < 0.0001, respectively) and in MRI inactive than in MRI active RRMS (P < 0.02, P < 0.01 and P < 0.001, respectively). An intrathecal synthesis of active MMP-2 was more frequent in RRMS than in inflammatory disorders (P < 0.01). Serum active MMP-2/TIMP-2 ratio and MS disease duration were positively correlated (P < 0.02). CONCLUSION: These findings suggest a potential role for MMP-2 activity in the termination of MS neuroinflammation related to remission of the disease and seem to indicate that serum MMP-2/TIMP-2 ratio may represent a useful biomarker for monitoring MS recovery phase.

Tissue inhibitors of matrix metalloproteinases are elevated in cerebrospinal fluid of neurodegenerative diseases.

Matrix metalloproteinases (MMPs) are implicated in the pathogenesis of diseases such as Alzheimer's Disease (AD) and amyotrophic lateral sclerosis (ALS). Increased expression of MMP-9 and TIMPs has been reported in postmortem AD and ALS brain tissue, as well as in ALS cerebrospinal fluid (CSF) and plasma. Although individual studies of MMP and TIMP expression in CSF have included AD and ALS samples, there are no studies comparing the expression of these proteins between neurodegenerative diseases. We measured the levels of matrix metalloproteinases (MMPs)-2 and -9 and the tissue inhibitor of MMPs (e.g. TIMP-1 and TIMP-2) in CSF samples from patients with Parkinson's Disease (PD), Huntington's Disease (HD), AD and ALS as compared to age-matched control patients. There was constitutive expression of the proform of gelatinase A (proMMP-2) on zymography gels in all CSF samples. Unexpectedly, there was an additional gelatinolytic band at 130 kDa of unknown etiology in the CSF samples of patients with PD (61% of patients studied), AD (61%), HD (25%) and ALS (39%). Levels of TIMP-1 were significantly elevated in CSF samples from all disease groups. TIMP-2 was significantly increased in CSF of AD and HD patients. MMP-2 levels did not differ significantly between groups. These findings show that TIMPs are elevated in the CSF of patients with neurodegenerative diseases suggesting a potential role of these endogenous inhibitors of matrix metalloproteinases in neurodegenerative diseases.

Matrix metalloproteinases and tissue inhibitors of metalloproteinases in cerebrospinal fluid differ in multiple sclerosis and Devic's neuromyelitis optica.

Matrix metalloproteinases (MMPs) are increased in the CSF of patients with multiple sclerosis. Devic's neuromyelitis optica (DNO) is a demyelinating syndrome that involves the optic nerve and cervical cord but differs pathologically from multiple sclerosis. Therefore, we hypothesized that the type of inflammatory reaction that causes MMPs to be elevated in multiple sclerosis would be absent in patients with DNO. CSF was collected from 23 patients with relapsing-remitting or secondary progressive multiple sclerosis, all of whom were experiencing acute symptoms, from seven patients with DNO, and from seven normal volunteers. Diagnoses were made according to current criteria on the basis of clinical manifestations, imaging results and CSF studies. IgG synthesis was increased in the CSF of multiple sclerosis patients but not in that of DNO patients. Zymography, reverse zymography and ELISA (enzyme-linked immunosorbent assay) were used to measure gelatinase A (MMP-2), gelatinase B (MMP-9) and tissue inhibitors of metalloproteinases (TIMPs). Zymograms showed that multiple sclerosis patients had elevated MMP-9 compared with DNO patients and controls (P: < 0.05). TIMP-1 and TIMP-2 levels were similar in all three groups. We conclude that multiple sclerosis patients have higher MMP-9 levels in the CSF than patients with DNO, which supports the different pathological mechanisms of these diseases.

Matrix metalloproteinase (MMP)-8 and MMP-9 in cerebrospinal fluid during bacterial meningitis: association with blood-brain barrier damage and neurological sequelae.

To evaluate the spectrum and regulation of matrix metalloproteinases (MMPs) in bacterial meningitis (BM), concentrations of MMP-2, MMP-3, MMP-8, and MMP-9 and endogenous inhibitors of metalloproteinases (TIMP-1 and TIMP-2) were measured in the cerebrospinal fluid (CSF) of 27 children with BM. MMP-8 and MMP-9 were detected in 91% and 97%, respectively, of CSF specimens from patients but were not detected in control patients. CSF levels of MMP-9 were higher (P<.05) in 5 patients who developed hearing impairment or secondary epilepsy than in those who recovered without neurological deficits. Levels of MMP-9 correlated with concentrations of TIMP-1 (P<.001) and tumor necrosis factor-alpha (P=.03). Repeated lumbar punctures showed that levels of MMP-8 and MMP-9 were regulated independently and did not correlate with the CSF cell count. Therefore, MMPs may derive not only from granulocytes infiltrating the CSF space but also from parenchymal cells of the meninges and brain. High concentrations of MMP-9 are a risk factor for the development of postmeningitidal neurological sequelae.

Marked increase of matrix metalloproteinase 9 in cerebrospinal fluid of patients with fungal or tuberculous meningoencephalitis.

Matrix metalloproteinases (MMPs) are believed to play an essential role in the breakdown of the extracellular matrix macromolecules in the blood-cerebrospinal fluid barrier and blood-brain barrier (BBB). In this study, the levels of MMP-2 and MMP-9 and their common tissue inhibitors of metalloproteinases (TIMP-1 and TIMP-2) were measured in the cerebrospinal fluid (CSF) from patients with various meningitides including aseptic, fungal and tuberculous ones. MMP-9 production level in CSF was more increased in subacute meningitis including fungal and tuberculous meningitis than in acute aseptic meningitis and non-inflammatory neurological diseases (NIDs). Enhanced production of MMP-9 was associated with high proteolytic activity detected by gelatin zymography. The MMP-2 and TIMP-1 levels in CSF of subacute meningitis were also higher than those of NIDs. In contrast, the TIMP-2 levels in CSF of either acute aseptic or subacute meningitis were not up-regulated compared with those of NIDs. The central nervous system (CNS) complications (i.e. disturbance of consciousness, psychiatric symptoms, urinary disturbance, etc.) during the course of meningitis showed good correlation with the enhanced production of MMP-9 in CSF. Immunohistochemical studies in tuberculous meningitis demonstrated that the infiltrating mononuclear cells in the meninges were immunoreactive for both MMP-2 and MMP-9. However, the infiltrating mononuclear cells into CNS parenchyma had immunoreactivity for MMP-9, but not for MMP-2. Taken together, those data suggest that MMP-9 in CSF may be a useful marker of encephalitogenecity during the course of subacute meningitis.

Matrix metalloproteinase-9 (gelatinase B) is selectively elevated in CSF during relapses and stable phases of multiple sclerosis.

Matrix metalloproteinases (MMPs) are a family of endopeptidases capable of enzymatic digestion of subendothelial basement membrane and other components of the extracellular matrix. Expression of MMP-2, -3, -7 and -9 is increased around multiple sclerosis plaques and in brain tissue in experimental allergic encephalomyelitis. To measure quantitatively the expression of these MMPs and their endogenous inhibitors (TIMP-1 and -2), we analysed samples from 52 patients with relapsing-remitting and primary progressive multiple sclerosis by ELISA (enzyme-linked immunosorbent assay) and substrate-gel electrophoresis (zymography). MMP-9 was increased over controls in 100% of relapsing-remitting multiple sclerosis cases, with similar levels detected in relapses and clinically stable phases of disease. In primary progressive multiple sclerosis, MMP-9 was increased in 57% of CSF samples, but concentrations were below those encountered in the relapsing-remitting form. The selective upregulation of MMP-9 suggests that T-cells and macrophages invading the brain parenchyma and the CSF space are the predominant source of MMP-9 in multiple sclerosis. TIMPs and other MMPs (MMP-2 and -3) were not upregulated or not detectable (MMP-7) in CSF of patients with relapsing-remitting and primary progressive multiple sclerosis. The sustained increase of MMP-9 in clinically stable multiple sclerosis supports the concept that multiple sclerosis is associated with ongoing proteolysis that may result in progressive tissue damage. The selective inhibition of MMP-9 could be a useful approach for the prevention of disease progression in multiple sclerosis.