scholarly journals Inhibition of Hippocampal Matrix Metalloproteinase-3 and -9 Disrupts Spatial Memory

2007 ◽  
Vol 2007 ◽  
pp. 1-8 ◽  
Author(s):  
John W. Wright ◽  
Travis E. Brown ◽  
Joseph W. Harding

Memory consolidation requires synaptic reconfiguration dependent upon extracellular matrix (ECM) molecules interacting with cell adhesion molecules. Matrix metalloproteinase (MMP) activity is responsible for transient alterations in the ECM that may be prerequisite to hippocampal-dependent learning. In support of this hypothesis we have measured increases in MMP-3 and MMP-9 levels within the hippocampus and prefrontal cortex during Morris water maze training. The present investigation extends these findings by determining that infusion of an MMP inhibitor (FN-439) into the dorsal hippocampus disrupted acquisition of this task. In vitro fluorescence enzyme assays to determine the specificity of FN-439 against the catalytic domains of MMP-3 and MMP-9 indicated mean±SEMIC50sof 16.2±7.8 and 210.5±37.8μM, respectively, while in situ zymography using hippocampal sections treated with FN-439 indicated significant reductions in MMP gelatinase activity. These results suggest that compromising the ability of the dorsal hippocampus to reconfigure ECM molecules by inhibiting MMP activity interferes with appropriate spatial memory acquisition, and support a role for hippocampal MMPs in the phenomena of spatial memory acquisition and storage.

2014 ◽  
Vol 111 (01) ◽  
pp. 140-153 ◽  
Author(s):  
Christopher Mason ◽  
Stephen Lynch ◽  
James Benjamin ◽  
Dani Ashak ◽  
Jamunabai M. Prakash ◽  
...  

SummaryMatrix metalloproteinase (MMP) activity is generally associated with normal or pathological extracellular processes such as tissue remodeling in growth and development or in tumor metastasis and angiogenesis. Platelets contain at least three MMPs, 1, 2 and 9 that have been reported to stimulate or inhibit agonist-induced platelet aggregation via extracellular signals. The non-selective Zn+2 chelating MMP inhibitor, 1,10-phenanthroline, and the serine protease inhibitor, AEBSF, were found to inhibit all tested agonist-induced platelet aggregation reactions. In vitro analysis demonstrated that 1,10-phenanthroline completely inhibited MMP-1,2,and 9 but had little to no effect on calpain activity while the converse was true with AEBSF. We now demonstrate that MMP-2 functions intracellularly to regulate agonistinduced platelet aggregations via the hydrolytic activation of talin, the presumed final activating factor of glycoprotein (GP)IIb/IIIa integrin (the inside-out signal). Once activated GPIIb/IIIa binds the dimeric fibrinogen molecule required for platelet aggregation. The active intracellular MMP-2 molecule is complexed with JAK 2/STAT 3, as demonstrated by the fact that all three proteins are co-immunoprecipitated with either anti-JAK 2, or anti-STAT 3 antibodies and by immunofluorescence studies. The MMP-2 platelet activation pathway can be synergistically inhibited with the non-selective MMP inhibitor, 1,10-phenanthroline, plus a JAK 2 inhibitor. This activation pathway is distinct from the previously reported calpain-talin activating pathway. The identification of a new central pathway for platelet aggregation presents new potential targets for drug regulation and furthers our understanding of the complexity of platelet activation mechanisms.


Author(s):  
Florian Pohlig ◽  
Jörg Ulrich ◽  
Ulrich Lenze ◽  
Heinrich M. L. Mühlhofer ◽  
Norbert Harrasser ◽  
...  

2022 ◽  
Vol 12 ◽  
Author(s):  
Ahmed M. Abu El-Asrar ◽  
Ajmal Ahmad ◽  
Mohd Imtiaz Nawaz ◽  
Mohammad Mairaj Siddiquei ◽  
Alexandra De Zutter ◽  
...  

Purpose: Endogenous tissue inhibitor of matrix metalloproteinase-3 (TIMP-3) has powerful regulatory effects on inflammation and angiogenesis. In this study, we investigated the role of TIMP-3 in regulating inflammation in the diabetic retina.Methods: Vitreous samples from patients with proliferative diabetic retinopathy (PDR) and non-diabetic patients were subjected to Western blot analysis. Streptozotocin-treated rats were used as a preclinical diabetic retinopathy (DR) model. Blood-retinal barrier (BRB) breakdown was assessed with fluorescein isothiocyanate (FITC)-conjugated dextran. Rat retinas, human retinal microvascular endothelial cells (HRMECs) and human retinal Müller glial cells were studied by Western blot analysis and ELISA. Adherence of human monocytes to HRMECs was assessed and in vitro angiogenesis assays were performed.Results: Tissue inhibitor of matrix metalloproteinase-3 in vitreous samples was largely glycosylated. Intravitreal injection of TIMP-3 attenuated diabetes-induced BRB breakdown. This effect was associated with downregulation of diabetes-induced upregulation of the p65 subunit of NF-κB, intercellular adhesion molecule-1 (ICAM-1), and vascular endothelial growth factor (VEGF), whereas phospho-ERK1/2 levels were not altered. In Müller cell cultures, TIMP-3 significantly attenuated VEGF upregulation induced by high-glucose (HG), the hypoxia mimetic agent cobalt chloride (CoCl2) and TNF-α and attenuated MCP-1 upregulation induced by CoCl2 and TNF-α, but not by HG. TIMP-3 attenuated HG-induced upregulation of phospho-ERK1/2, caspase-3 and the mature form of ADAM17, but not the levels of the p65 subunit of NF-κB and the proform of ADAM17 in Müller cells. TIMP-3 significantly downregulated TNF-α-induced upregulation of ICAM-1 and VCAM-1 in HRMECs. Accordingly, TIMP-3 significantly decreased spontaneous and TNF-α- and VEGF-induced adherence of monocytes to HRMECs. Finally, TIMP-3 significantly attenuated VEGF-induced migration, chemotaxis and proliferation of HRMECs.Conclusion:In vitro and in vivo data point to anti-inflammatory and anti-angiogenic effects of TIMP-3 and support further studies for its applications in the treatment of DR.


2018 ◽  
Author(s):  
Demirhan Çetereisi ◽  
Ioannis Kramvis ◽  
Titia Gebuis ◽  
Rolinka J. van der Loo ◽  
Yvonne Gouwenberg ◽  
...  

AbstractG-protein-coupled receptor 158 (Gpr158) is highly expressed in striatum, hippocampus and prefrontal cortex. It gained attention as it was implicated in physiological responses to stress and depression. Recently, Gpr158 has been shown to act as a pathway-specific synaptic organizer in the hippocampus, required for proper mossy fiber-CA3 neurocircuitry establishment, structure, and function. Although rodent Gpr158 expression is highest in CA3, considerable expression occurs in CA1 especially after the first postnatal month. Here, we combined hippocampal-dependent behavioral paradigms with subsequent electrophysiological and morphological analyses from the same group of mice to assess the effects of Gpr158 deficiency on CA1 physiology and function. We demonstrate deficits in spatial memory acquisition and retrieval in the Morris water maze paradigm, along with deficits in the acquisition of extinction memory in the passive avoidance test in Gpr158 KO mice. Electrophysiological recordings from CA1 pyramidal neurons revealed normal basal excitatory and inhibitory synaptic transmission, however, Schaffer collateral stimulation yielded dramatically reduced post-synaptic currents. Interestingly, intrinsic excitability of CA1 pyramidals was found increased, potentially acting as a compensatory mechanism to the reductions in Schaffer collateral-mediated drive. Both ex vivo and in vitro, neurons deficient for Gpr158 exhibited robust reductions in dendritic architecture and complexity, i.e., reduced length, surface, bifurcations, and branching. This effect was localized in the apical but not basal compartment of adult CA1 pyramidals, indicative of pathway-specific alterations. A significant positive correlation between spatial memory acquisition and extent of complexity of CA1 pyramidals was found. Taken together, we provide first evidence of significant disruptions in hippocampal CA1 neuronal dendritic architecture and physiology, driven by Gpr158 deficiency. Importantly, the hippocampal neuronal morphology deficits appear to support the impairments in spatial memory acquisition observed in Gpr158 KO mice.


2020 ◽  
Vol 11 ◽  
Author(s):  
Agnieszka Sowinska ◽  
Merlin Rensing ◽  
Lena Klevenvall ◽  
Manoj Neog ◽  
Peter Lundbäck ◽  
...  

Extracellular HMGB1 acts as an alarmin in multiple autoimmune diseases. While its release and functions have been extensively studied, there is a substantial lack of knowledge regarding HMGB1 regulation at the site of inflammation. Herein we show that enzymes present in arthritis-affected joints process HMGB1 into smaller peptides in vitro. Gel electrophoresis, Western blotting and mass spectrometry analyses indicate cleavage sites for human neutrophil elastase, cathepsin G, and matrix metalloproteinase 3 within the HMGB1 structure. While human neutrophil elastase and matrix metalloproteinase 3 might alter the affinity of HMGB1 to its receptors by cleaving the acidic C-terminal tail, cathepsin G rapidly and completely degraded the alarmin. Contrary to a previous report we demonstrate that HMGB1 is not a substrate for dipeptidyl peptidase IV. We also provide novel information regarding the presence of these proteases in synovial fluid of juvenile idiopathic arthritis patients. Correlation analysis of protease levels and HMGB1 levels in synovial fluid samples did not, however, reveal any direct relationship between the recorded levels. This study provides knowledge of proteolytic processing of HMGB1 relevant for the regulation of HMGB1 during inflammatory disease.


2005 ◽  
Vol 17 (9) ◽  
pp. 97
Author(s):  
T. J. Kaitu'u ◽  
N. B. Morison ◽  
L. A. Salamonsen

Strong correlative evidence supports a role for matrix metalloproteinases (MMPs) in the tissue breakdown at menstruation. As menstruation occurs in very few species besides women, there is a lack of suitable and easily accessible animal models available to examine the functional significance of potential key mediators of this process. A mouse model of endometrial breakdown and repair has been developed,1 which morphologically resembles that of human endometrium at menstruation. Previous studies in our laboratory showed that the expression patterns of various MMPs in the mouse model closely resembled those seen in the human.2 Administration of doxycycline, a broad spectrum MMP inhibitor, decreased gelatinase activity, but had no effect on tissue breakdown in this model. The aim of the present study was to further examine the importance of MMPs in endometrial breakdown and repair via administration of batimistat, a highly potent and specific MMP inhibitor. Batimistat was administered I.P to mice 24 h prior to the expected time of endometrial breakdown. The efficacy of batimistat within the uterus was proven using in situ zymography, which identifies MMP activity (rather than latent forms). This demonstrated that batimistat was reaching its target organ and effectively inhibiting MMP activities (both gelatinase and collagenase). Examination of gross uterine morphology revealed no apparent difference between groups, with batimistat treated uteri displaying a similar extent of tissue breakdown and repair to their control counterparts. Measurement of the breaking down area compared to total endometrial area revealed no difference between control and batimistat treatment, with the breaking down areas being 69 ±13% and 72 ± 9.8% of total endometrial cross-sectional area respectively. There was likewise no effect on endometrial repair. The results of this study together with our previous study using doxycycline, indicate that MMPs are not the key mediators of endometrial breakdown in this model. (1)Shen et al. (2004) Reprod. Fert. Dev. 16(Suppl), A265, p. 97.(2)Brasted et al. (2003) Biol. Reprod. 69, 1273.


2021 ◽  
Vol 14 (2) ◽  
pp. 135
Author(s):  
Eunkuk Park ◽  
Chang Gun Lee ◽  
Seung Hee Yun ◽  
Seokjin Hwang ◽  
Hyoju Jeon ◽  
...  

Arthritis is a common inflammatory disease that causes pain, stiffness, and joint swelling. Here, we investigated the ameliorative effects of loganin on arthritis in vitro and in vivo. A single bioactive compound was fractionated and isolated from Cornus officinalis (CO) extract to screen for anti-arthritic effects. A single component, loganin, was identified as a candidate. The CO extract and loganin inhibited the expression of factors associated with cartilage degradation, such as cyclooxygenase-2 (COX-2), matrix metalloproteinase 3 (MMP-3), and matrix metalloproteinase 13 (MMP-13), in interukin-1 beta (IL-1β)-induced chondrocyte inflammation. In addition, prostaglandin and collagenase levels were reduced following treatment of IL-1β-induced chondrocytes with loganin. In the destabilization of the medial meniscus (DMM)-induced mouse model, loganin administration attenuated cartilage degeneration by inhibiting COX-2, MMP-3, and MMP-13. Transverse micro-CT images revealed that loganin reduced DMM-induced osteophyte formation. These results indicate that loganin has protective effects in DMM-induced mice.


2018 ◽  
Vol 9 (1) ◽  
pp. 43-53 ◽  
Author(s):  
Gennadiy Fonar ◽  
Baruh Polis ◽  
Tomer Meirson ◽  
Alexander Maltsev ◽  
Evan Elliott ◽  
...  

Abstract Arginine is one of the most versatile semi-essential amino acids. Further to the primary role in protein biosynthesis, arginine is involved in the urea cycle, and it is a precursor of nitric oxide. Arginine deficiency is associated with neurodegenerative diseases such as Parkinson’s, Huntington’s and Alzheimer’s diseases (AD). In this study, we administer arginine intracerebroventricularly in a murine model of AD and evaluate cognitive functions in a set of behavioral tests. In addition, the effect of arginine on synaptic plasticity was tested electrophysiologically by assessment of the hippocampal long-term potentiation (LTP). The effect of arginine on β amyloidosis was tested immunohistochemically. A role of arginine in the prevention of cytotoxicity and apoptosis was evaluated in vitro on PC-12 cells. The results indicate that intracerebroventricular administration of arginine improves spatial memory acquisition in 3xTg-AD mice, however, without significantly reducing intraneuronal β amyloidosis. Arginine shows little or no impact on LTP and does not rescue LTP deterioration induced by Aβ. Nevertheless, arginine possesses neuroprotective and antiapoptotic properties.


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