Collagenase-Induced Rat Intra-Striatal Hemorrhage Mimicking Severe Human Intra-Striatal Hemorrhage.

Basal ganglia hemorrhage accounts for approximately 50% of all hemorrhagic strokes. A good rat model that produces severe intrastriatal hemorrhage (ISH) mimicking human severe ISH is lacking. The present study compared the intra-striatal injection of 0.2 U with that of 0.6 U of collagenase in inducing severe ISH in rats. Three-Tesla (3T) magnetic resonance imaging (MRI) was used to evaluate brain injuries in terms of hematoma size (volume), midline shift (MLS), and brain edema. This evaluation was further substantiated by determination of behavior and neurologic functions and mortality over 56 h. The 0.2 U collagenase caused hematoma volume increases for 10.3 to 30.1 mm³, while the 0.6 U caused 36.4 to 114.8 mm³, at post-ISH 1 h to 56 h. The 0.6 U collagenase significantly increased MLS to 1.5-3.0 times greater than the 0.2 U did at all post-intracerebral hemorrhage (ICH) time points. The MLS increased dependently with hematoma expansion with high correlation coefficients, yet no mortality occurred. These two dosages, nevertheless, caused the same pattern and severity in relative apparent diffusion coefficient (rADC) changes for three regions of interest (ROIs). Both ISH models induced consistent behavior deficits. The larger dosage produced severe brain injuries as well as neurological deficits, more closely mimicking severe human ISH. Hematoma volume and MLS can be the most useful parameters for evaluating the ISH severity in the present experimental model. The larger dosage, therefore, would be useful for investigating the pathophysiology of the severer ISH in the striatum. This may be applied for evaluating potential therapeutic strategies and outcomes in the future.

Acute Alcohol Intoxication Aggravates Brain Injury Caused by Intracerebral Hemorrhage in Rats.

OBJECTIVE: Alcohol intoxication is associated with worse intracerebral hemorrhage (ICH) outcome, indicating the important role of alcohol in ICH pathogenesis. We intended to investigate the effects of ethanol pretreatment on the severity of ICH-induced brain injury in rats. METHODS: At 1 hour after intraperitoneal injection of ethanol (3 g/kg), 0.2 U bacterial collagenase was infused into the striatum of male Sprague-Dawley rats to induce ICH. Accumulative mortality rate, body weight changes, and motorsensory and neurological abnormalities were evaluated. The hemorrhagic volume, hematoma expansion, and water content were measured by Drabkin's method, morphometric assay, and dry/wet method, respectively. Blood-brain barrier disruption was assessed using Evans blue assay. Oxidative stress was evaluated by the enzymatic activity of glutathione peroxidase, oxidation of hydroethidine, and the production of malondialdehyde. Cerebral blood flow perfusion volume and hypo-/hyperperfusion neuroimaging were examined by magnetic resonance imaging. RESULTS: Ethanol pretreatment aggravates the hematoma hemolysis, hemorrhagic volume, hematoma expansion, brain edema, blood-brain barrier disruption, microglial activation, elevated oxidative stress, and neuroinflammation in the hemorrhagic striatum. The summation effect of these consequences is the major cause of marked neurological impairment and higher mortality rate (64%) in ethanol-pretreated rats with ICH. CONCLUSION: This is a novel model to evaluate the effects of high-dose alcohol administration on experimental ICH rats. IMPLICATIONS: The present study may provide clues for making novel strategies in the management of patients with ICH who overconsume alcoholic drinks before the attack.

Systemic administration of urocortin after intracerebral hemorrhage reduces neurological deficits and neuroinflammation in rats.

BACKGROUND: Intracerebral hemorrhage (ICH) remains a serious clinical problem lacking effective treatment. Urocortin (UCN), a novel anti-inflammatory neuropeptide, protects injured cardiomyocytes and dopaminergic neurons. Our preliminary studies indicate UCN alleviates ICH-induced brain injury when administered intracerebroventricularly (ICV). The present study examines the therapeutic effect of UCN on ICH-induced neurological deficits and neuroinflammation when administered by the more convenient intraperitoneal (i.p.) route. METHODS: ICH was induced in male Sprague-Dawley rats by intrastriatal infusion of bacterial collagenase VII-S or autologous blood. UCN (2.5 or 25 µg/kg) was administered i.p. at 60 minutes post-ICH. Penetration of i.p. administered fluorescently labeled UCN into the striatum was examined by fluorescence microscopy. Neurological deficits were evaluated by modified neurological severity score (mNSS). Brain edema was assessed using the dry/wet method. Blood-brain barrier (BBB) disruption was assessed using the Evans blue assay. Hemorrhagic volume and lesion volume were assessed by Drabkin's method and morphometric assay, respectively. Pro-inflammatory cytokine (TNF-α, IL-1ß, and IL-6) expression was evaluated by enzyme-linked immunosorbent assay (ELISA). Microglial activation and neuronal loss were evaluated by immunohistochemistry. RESULTS: Administration of UCN reduced neurological deficits from 1 to 7 days post-ICH. Surprisingly, although a higher dose (25 µg/kg, i.p.) also reduced the functional deficits associated with ICH, it is significantly less effective than the lower dose (2.5 µg/kg, i.p.). Beneficial results with the low dose of UCN included a reduction in neurological deficits from 1 to 7 days post-ICH, as well as a reduction in brain edema, BBB disruption, lesion volume, microglial activation and neuronal loss 3 days post-ICH, and suppression of TNF-α, IL-1ß, and IL-6 production 1, 3 and 7 days post-ICH. CONCLUSION: Systemic post-ICH treatment with UCN reduces striatal injury and neurological deficits, likely via suppression of microglial activation and inflammatory cytokine production. The low dose of UCN necessary and the clinically amenable peripheral route make UCN a potential candidate for development into a clinical treatment regimen.

Induction of GAP-43 modulates neuroplasticity in PBSC (CD34+) implanted-Parkinson's model.

As a result of the progressive decrease in efficacy of drugs used to treat Parkinson's disease (PD) and the rapid development of motor complications, effective alternative treatments for PD are required. In a 6-hydroxydopamine (6-OHDA)-induced Parkinson's rat model, intracerebral peripheral blood stem cell (CD34(+)) (PBSC) transplantation significantly protected dopaminergic neurons from 6-OHDA-induced neurotoxicity, enhanced neural repair of tyrosine hydroxylase neurons through up-regulation of Bcl-2, facilitated stem cell plasticity, and attenuated activation of microglia, in comparison with vehicle-control rats. The 6-OHDA-lesioned hemi-Parkinsonian rats receiving intrastriatal transplantation of PBSCs also showed: 1) enhanced glucose metabolism in the lesioned striatum and thalamus, demonstrated by [(18)F]fluoro-2-deoxyglucose positron emission tomography (FDG-PET), 2) improved neurochemical activity as shown by proton magnetic resonance spectroscopy ((1)H-MRS), and 3) significantly reduced rotational behavior in comparison with control lesioned rats. These observations might be explained by an up-regulation of growth-associated protein 43 (GAP-43) expression because improvements in neurological dysfunction were blocked by injection of MK-801 in the PBSC-treated group. In addition, a significant increase in neurotrophic factor expression was found in the ipsilateral hemisphere of the PBSC-treated group. In summary, this protocol may be a useful strategy for the treatment of clinical PD.

Delayed formation of hematomas with ethanol preconditioning in experimental intracerebral hemorrhage rats.

OBJECTIVE: Spontaneous intracerebral hemorrhage (ICH) accounts for 10%-15% of all strokes and causes high mortality and morbidity. In the previous study, we demonstrated that ethanol could aggravate the severity of brain injury after ICH by increasing neuroinflammation and oxidative stress. In this study, we further investigate the acute effects of ethanol on brain injury within 24 h after ICH. MATERIALS AND METHODS: Totally, 66 male Sprague-Dawley rats were assigned randomly into two groups: saline pretreatment before ICH (saline + ICH), and ethanol pretreatment before ICH (ethanol + ICH). Normal saline (10 mL/kg) or ethanol (3 g/kg, in 10 mL/kg normal saline) was administered intraperitoneally 1 h before induction of experimental ICH. Bacterial collagenase VII-S (0.23 U in 1.0 µL sterile saline) was injected into the right striatum to induce ICH in the rats. We evaluated the hematoma expansion, hemodynamic parameters (heart rate and blood pressure), activated partial thromboplastin time (aPTT), prothrombin time (PT), and striatal matrix metallopeptidase 9 (MMP-9) expressions at 3, 6, 9, and 24 h after ICH. RESULTS: The ethanol + ICH group exhibited decreased hematoma at 3 h after ICH; nevertheless, there was a larger hematoma compared with the saline + ICH group at 9 and 24 h after ICH. The ethanol + ICH group had lower blood pressure at 3, 6, and 9 h post-ICH, but both groups maintained similar heart rates after ICH. There was no significant difference in the aPTT and PT between the two groups. Incremental ethanol concentrations had no influence on collagenase VII-S activity at 120 min in vitro. MMP-9 expression was upregulated in the right striata of the ethanol + ICH group, especially at 3 and 9 h after ICH. CONCLUSION: Ethanol delayed hematoma formation in the first 3 h due to a hypotensive effect; however, the accelerated growth of hematomas after 9 h may be a sequela of ethanol-induced MMP-9 activation.

Therapeutic effects of human urocortin-1, -2 and -3 in intracerebral hemorrhage of rats.

Urocortin exerts neuroprotective effects in intracerebral hemorrhage (ICH) of rats. For pre-clinical trial, we intended to study the neuroprotective efficacy of human UCN (hUCN)-1, -2 and -3 in treating ICH rats. ICH was induced by infusing bacterial collagenase VII (0.23 U in sterile saline) to the striatum. The hUCN-1, -2, and -3 were administrated (2.5µg/kg, i.p.) at 1h after ICH insult, respectively. Neurological deficits were evaluated by modified Neurological Severity Scores. Brain edema and hematoma expansion was evaluated by coronal T2-WI and DWI magnetic resonance imaging on 1, 3, 6, 24, and 56h after ICH insult. Blood-brain barrier permeability was evaluated by Evans blue assay on day 3 after ICH. Brain lesion volume was evaluated by morphormetric measurement on day 7 after ICH. Our results demonstrated that the hUCN-1 significantly reduced hematoma, blood-brain barrier disruption and neurological deficits on day 3, and brain lesion volume on day 7 after ICH insult. The prediction of secondary structure of the hUCNs clarifies that the percentage of alpha-helix, random coil and extended strand between rat-UCN (rUCN)-1 and hUCN-1 are the same. The structure similarity between human- and rat-UCN-1 may be one of the reasons that both can exert similar therapeutic potential in ICH rats.

Therapeutic benefit of urocortin in rats with intracerebral hemorrhage.

OBJECT: Intracerebral hemorrhage (ICH) accounts for about 15% of all deaths due to stroke. It frequently causes brain edema, leading to an expansion of brain volume that exerts a negative impact on ICH outcomes. The ICH-induced brain edema involves inflammatory mechanisms. The authors' in vitro study shows that urocortin (UCN) exhibits antiinflammatory and neuroprotective effects. Therefore, the neuroprotective effect of UCN on ICH in rats was investigated. METHODS: Intracerebral hemorrhage was induced by an infusion of bacteria collagenase type VII-S or autologous blood into the unilateral striatum of anesthetized rats. At 1 hour after the induction of ICH, UCN (0.05, 0.5, and 5 µg) was infused into the lateral ventricle on the ipsilateral side. The authors examined the injury area, brain water content, blood-brain barrier permeability, and neurological function. RESULTS: The UCN, administered in the ipsilateral lateral ventricle, was able to penetrate into the injured striatum. Posttreatment with UCN reduced the injury area, brain edema, and blood-brain barrier permeability and improved neurological deficits of rats with ICH. CONCLUSIONS: Posttreatment with UCN through improving neurological deficits of rats with ICH dose dependently provided a potential therapeutic agent for patients with ICH or other brain injuries.