Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.4.24.3 (collagenase)
18,340 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intracranial bleeding is an important cause of brain masses and edema. To study the pathophysiology of intracerebral hemorrhage, we produced experimental hemorrhages in 53 rats and characterized the lesion by histology, brain water content, and behavior. Adult rats had 2 microliters saline containing 0.5 unit bacterial collagenase infused into the left caudate nucleus. Histologically, erythrocytes were seen around blood vessels at the needle puncture site within the first hour. By 4 hours there were hematomas, the size of which depended on the amount of collagenase injected. Necrotic masses containing fluid, blood cells, and fibrin were seen at 24 hours. Lipid-filled macrophages were observed at 7 days and cysts at 3 weeks. Water content was significantly increased 4, 24, and 48 hours after infusion at the needle puncture site and for 24 hours in posterior brain sections. Behavioral abnormalities were present for 48 hours, with recovery of function occurring during the first week. Brain tissue contains Type IV collagen in the basal lamina. Collagenase, which occurs in an inactive form in cells, is released and activated during injury, leading to disruption of the extracellular matrix. Collagenase-induced intracerebral hemorrhage is a reproducible animal model for the study of the effects of the hematoma and brain edema.
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PMID:Collagenase-induced intracerebral hemorrhage in rats. 216 Jan 42

Cell bodies and their dendrites of motor neurons, motor-related neurons, and certain other subsets of neurons such as GABAergic interneurons in the mature brain and spinal cord possess intensely negatively charged perineuronal or perisynaptic nets of proteoglycans which are linked to the nerve cell surface glycoproteins. These perineuronal nets of proteoglycans are digested by chondroitinase ABC, hyaluronidase, or collagenase, but not by endo-alpha-N-acetylgalactosaminidase, which is reactive to the nerve cell surface glycoproteins. Aggrecan, versican, neurocan, and brevican are members of a family of chondroitin sulfate proteoglycans that bind to hyaluronan. Neurocan- or brevican-deficient mice showed a regionally heterogeneous composition of proteoglycans in perineuronal nets. Aggrecan glycoforms contribute to the molecular heterogeneity of the perineuronal nets. Proteoglycans such as phosphacan are included in matrix-associated proteoglycans. The extracellular matrix glycoprotein tenascin-R is accumulated in the perineuronal nets. The perineuronal proteoglycans are produced by associated satellite astrocytes just before weaning, while the nerve cell surface glycoproteins are produced by the associated nerve cells at earlier stages after birth. The perineuronal proteoglycans may entrap the tissue fluid and form a perineuronal gel layer which protects the synapses as a "perisynaptic barrier". Degradation of the perineuronal proteoglycans or perisynaptic barrier by treatment with chondroitinase ABC or hyaluronidase reactivates the neuronal plasticity or promotes the functional recovery of a severed nervous system. Another set of perineuronal nets occurs, which are intensely positively charged and contain guanidino compounds. It is considered that these intensely positively charged nets are intermingled with the intensely negatively charged ones of proteoglycans.
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PMID:Perisynaptic barrier of proteoglycans in the mature brain and spinal cord. 1452 61

The selective cyclooxygenase-2 (COX-2) inhibitor has been reported to have antiinflammatory, neuroprotective, and antioxidant effects in ischemia models. In this study, the authors examined whether a selective COX-2 inhibitor (celecoxib) reduces cerebral inflammation and edema after intracerebral hemorrhage (ICH), and whether functional recovery is sustained with longer treatment. ICH was induced using collagenase in adult rats. Celecoxib (10 or 20 mg/kg) was administered intraperitoneally 20 minutes, 6 hours, and 24 hours after ICH and then daily thereafter. Seventy-two hours after ICH induction, the rats were killed for histologic assessment and measurement of brain edema and prostaglandin E2. Behavioral tests were performed before and 1, 7, 14, 21, and 28 days after ICH. The brain water content of celecoxib-treated rats decreased both in lesioned and nonlesioned hemispheres in a dose-dependent manner. Compared with the ICH-only group, the number of TUNEL-positive, myeloperoxidase-positive, or OX42-positive cells was decreased in the periphery of hematoma and brain prostaglandin E2 level was reduced in the celecoxib-treated group. Celecoxib-treated rats recovered better by the behavioral tests at 7 days after ICH throughout the 28-day period, and the earlier the drug was administered, the better the functional recovery. Evidence of similar effects in an autologous blood-injected model showed that direct collagenase toxicity was not the major cause of inflammation or cell death. These data suggest that celecoxib treatment after ICH reduces prostaglandin E2 production, brain edema, inflammation, and perihematomal cell death in the perihematomal zone and induces better functional recovery.
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PMID:Celecoxib induces functional recovery after intracerebral hemorrhage with reduction of brain edema and perihematomal cell death. 1536 23

Granulocyte colony-stimulating factor (G-CSF) has been used in the treatment of neutropenia in hematologic disorders. The neuroprotective and anti-inflammatory effects of G-CSF were reported in various neurological disease models. In this study, we examined whether G-CSF induces functional recovery after intracerebral hemorrhage (ICH). ICH was induced using collagenase injection in adult rats. Either G-CSF (50 microg/kg, i.p.) or saline was given from 2 h after ICH and every 24 h for 3 days. 72 h after ICH induction, the rats were sacrificed for histological analysis and measurement of brain edema. Behavioral tests were performed before and 1, 7, 14, 21, 28, and 35 days after ICH. We also measured the blood-brain barrier (BBB) permeability using Evans blue dye injection method. G-CSF-treated rats recovered better on rotarod and limb placing tests, starting from 14 days throughout 5 weeks after ICH. The brain water content and BBB permeability of G-CSF-treated group decreased in the lesioned hemispheres compared with those of ICH-only group. In G-CSF-treated group, the number of TUNEL+, myeloperoxidase+, and OX42+ cells was smaller than that of ICH-only group in the periphery of hematoma. These findings suggest that G-CSF induces long-term sensorimotor recovery after ICH with reduction of brain edema, inflammation, and perihematomal cell death.
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PMID:Granulocyte colony-stimulating factor induces sensorimotor recovery in intracerebral hemorrhage. 1582 21

Glutamate is accumulated in abundance during the early period of experimental hematoma, and the activation of N-methyl-D-aspartate (NMDA) receptors by glutamate can result in an influx of calcium and neuronal death in cases of intracerebral hemorrhage (ICH). Memantine, which is known to be a moderate-affinity, uncompetitive, NMDA receptor antagonist, was investigated with regard to its ability to block the glutamate overstimulation and tissue plasminogen activator (tPA)/urokinase plasminogen activator (uPA)/matrix metalloproteinase (MMP)-9 modulation in experimental ICH. Intracerebral hemorrhage was induced via the infusion of collagenase into the left basal ganglia of adult rats. Either memantine (20 mg/kg/day) or PBS was intraperitoneally administered 30 min after the induction of ICH, and, at daily intervals afterwards, for either 3 or 14 days. Hemorrhage volume decreased by 47% in the memantine group, as compared with the ICH-only group. In the memantine group, the numbers of TUNEL+, myeloperoxidase (MPO)+, and OX42+ cells decreased in the periphery of the hematoma. Memantine resulted in an upregulation of bcl-2 expression and an inhibition of caspase-3 activation. Memantine also exerted a profound inhibitory effect on the upregulation of tPA/uPA mRNA, and finally decreased the MMP-9 level in the hemorrhagic brain. In modified limb-placing test, the memantine-treated rats exhibited lower scores initially, and recovered more quickly and thoroughly throughout the 35 days of the study. Here, we show that memantine causes a reduction of hematoma expansion, coupled with an inhibitory effect on the tPA/uPA and MMP-9 level. Subsequently, memantine was found to reduce inflammatory infiltration and apoptosis, and was also determined to induce functional recovery after ICH.
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PMID:Memantine reduces hematoma expansion in experimental intracerebral hemorrhage, resulting in functional improvement. 1610 86

Intracerebral hemorrhage (ICH) is a severe complication in diabetic patients. Currently, physical exercise is recommended as a behavioral intervention to promote functional recovery in brain diseases, including ICH. Recently, hyperglycemia is known to aggravate brain injury in experimental ICH. Here, we examined the effect of treadmill exercise on the intrastriatal hemorrhage-induced neuronal cell death and cell proliferation in the dentate gyrus of hyperglycemic rats. Hyperglycemia was induced by the intraperitoneal injection of 50 mg/kg streptozotocin (STZ). Intrastriatal hemorrhage was induced by the infusion of 0.2 U collagenase into the striatum using stereotaxic instrument. Rats in the exercise groups were forced to run on a treadmill for 30 min daily for 10 days. Apoptosis was assessed by the terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay. Cell proliferation was assessed by the 5-bromo-2'-deoxyuridine (BrdU) immunohistochemistry. Our data showed that in rats started treadmill exercise 24 h after ICH induction, the size of lesion induced by hemorrhage and the number of apoptotic cells were decreased significantly. The number of proliferating cells in the dentate gyrus was significantly decreased in hyperglycemic rats. Treadmill exercise markedly enhanced cell proliferation in the dentate gyrus of hyperglycemic rats. The data suggest that treadmill exercise may provide therapeutic value to ICH patients with hyperglycemia by suppressing neuronal apoptosis and increasing cell proliferation.
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PMID:Early treadmill exercise decreases intrastriatal hemorrhage-induced neuronal cell death and increases cell proliferation in the dentate gyrus of streptozotocin-induced hyperglycemic rats. 1626 Mar 51

After moderate intracerebral hemorrhage (ICH), both hypothermia (HYPO) and constraint-induced movement therapy (CIMT) improve recovery and reduce the volume of brain injury. We tested the hypothesis that more severe ICH requires both cytoprotection and rehabilitation to significantly improve recovery. Rats were subjected to a unilateral striatal ICH via collagenase infusion. Rats remained normothermic or were subjected to mild HYPO ( approximately 2 days) starting 12 h later. Fourteen days after ICH, half of the rats received CIMT (7 days of restraint of the less affected limb plus daily exercises); the remainder were untreated. Walking, limb use and skilled reaching were assessed up to 60 days, at which time animals were euthanized and the volume of tissue lost was determined. The HYPO treatment alone did not improve outcome, whereas CIMT alone provided significant benefit on the limb use asymmetry test. In the staircase test, the greatest benefit was achieved with the combination of HYPO and CIMT treatments. The volume of tissue lost after ICH was similar among groups arguing against cytoprotection as a mechanism of functional recovery. Finally, these findings suggest that, at least under the present circumstances (e.g., severe striatal ICH), CIMT provides superior benefit to HYPO and that combination therapy will sometimes further improve recovery.
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PMID:Combined use of a cytoprotectant and rehabilitation therapy after severe intracerebral hemorrhage in rats. 1626 39

Successful clinical translation of prospective cytoprotectants will likely occur only with treatments that improve functional recovery in preclinical (rodent) studies. Despite this assumption, many rely solely on histopathologic end points or the use of one or two simple behavioral tests. Presently, we used a battery of tests to gauge recovery after a unilateral intracerebral hemorrhagic stroke (ICH) targeting the striatum. In total, 60 rats (N=15 per group) were stereotaxically infused with 0 (SHAM), 0.06 (MILD lesion), 0.12 (MODERATE lesion), or 0.18 U (SEVERE lesion) of bacterial collagenase. This created a range of injury akin to moderate (from SEVERE to MODERATE or MODERATE to MILD lesion size approximately 30% reduction) and substantial cytoprotection (SEVERE to MILD lesion size--51% reduction). Post-ICH functional testing occurred over 30 days. Tests included the horizontal ladder and elevated beam tests, swimming, limb-use asymmetry (cylinder) test, a Neurologic Deficit Scale, an adhesive tape removal test of sensory neglect, and the staircase and single pellet tests of skilled reaching. Most tests detected significant impairments (versus SHAM), but only a few (e.g., staircase) frequently distinguished among ICH groups and none consistently differentiated among all ICH groups. However, by using a battery of tests we could behaviorally distinguish groups. Thus, preclinical testing would benefit from using a battery of behavioral tests as anything less may miss treatment effects. Such testing must be based on factors including the type of lesion, the postoperative delay and the time required to complete testing.
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PMID:Gauging recovery after hemorrhagic stroke in rats: implications for cytoprotection studies. 1639 82

Erythropoietin (EPO), a pleiotropic cytokine involved in erythropoiesis, is tissue-protective in ischemic, traumatic, toxic and inflammatory injuries. In this study, we investigated the effect of EPO in experimental intracerebral hemorrhage (ICH). Two hours after inducing ICH via the stereotaxic infusion of collagenase, recombinant human EPO (500 or 5000 IU/kg, ICH + EPO group) or PBS (ICH + vehicle group) was administered intraperitoneally, then once daily afterwards for 1 or 3 days. ICH + EPO showed the better functional recovery in both rotarod and modified limb placing tests. The brain water content was decreased in ICH + EPO dose-dependently, as compared with ICH + vehicle. The effect of EPO on the brain water content was inhibited by N(omega)-Nitro-L-arginine methyl ester hydrochloride (L-NAME, 10 mg/kg). Mean hemorrhage volume was also decreased in ICH + EPO. EPO reduced the numbers of TUNEL +, myeloperoxidase + or OX-42 + cells in the perihematomal area. In addition, EPO reduced the mRNA level of TNF-alpha, Fas and Fas-L, as well as the activities of caspase-8, 9 and 3. EPO treatment showed up-regulations of endothelial nitric oxide synthase (eNOS) and p-eNOS, pAkt, pSTAT3 and pERK levels. These data suggests that EPO treatment in ICH induces better functional recovery with reducing perihematomal inflammation and apoptosis, coupled with activations of eNOS, STAT3 and ERK.
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PMID:Erythropoietin reduces perihematomal inflammation and cell death with eNOS and STAT3 activations in experimental intracerebral hemorrhage. 1653 88

Exercise can improve recovery following ischemia and intracerebral hemorrhage (ICH) in rodents. We tested whether forced exercise (EX; running wheel) prior to and/or following ICH in rats would reduce lesion volume and improve functional outcome (walking, skilled reaching, spontaneous paw usage) at 7 weeks post-ICH. A striatal hemorrhage was produced by infusing collagenase. First, we compared animals that received EX (2 weeks; 1 h/day) ending two days prior to ICH and/or starting two weeks following ICH. EX did not improve functional recovery or affect lesion size. Doubling the amount of EX given per day (two 1-h sessions) both prior to and following ICH did not alter lesion volume, but worsened recovery. We then determined if EX (1 h/day) prior to and following ICH would affect outcome after a somewhat milder insult. There were no differences between the groups in lesion volume or recovery. Finally, we used a hemoglobin assay at 12 h following ICH to determine if pre-stroke EX (2 weeks; 1 h/day) aggravated bleeding. It did not. These observations suggest that EX does not improve outcome when given prior to and/or when delayed following ICH. Effective rehabilitation for ICH will likely require more complex interventions than forced running.
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PMID:Forced exercise does not improve recovery after hemorrhagic stroke in rats. 1685 89


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