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Bradykinin is a mediator of vasogenic brain edema formation. Recent reports suggest that bradykinin interacts with nitric oxide synthase (NOS) system in the central nervous system (CNS). However, role of bradykinin in spinal cord injury (SCI) induced alterations in the blood-spinal cord barrier (BSCB), spinal cord blood flow (SCBF), edema formation and cell changes are still not well known. Our previous reports showed that SCI induces marked upregulation of neuronal NOS (nNOS) in the cord associated with BSCB disruption, edema formation and cell injury. Thus, a possibility exists that bradykinin participates in SCI induced nNOS upregulation and cord pathology. To explore this idea a potent bradykinin B2 receptor antagonist HOE-140 was used in our rat model of SCI and cord pathology. SCI was inflicted in Equithesin anesthetized rats by making a longitudinal incision (2mm deep and 5mm long) into the right dorsal horn of the T10-11 segment. The animals were allowed to survive 5h after injury. A focal SCI significantly disrupted BSCB to Evans blue and I-[131]-sodium in the traumatized and adjacent segments. Interestingly, far remote spinal cord segments C4 and T5 segments also affected within 5 h. These spinal cord segments also exhibited pronounced reductions in the SCBF (mean-30%), increased edematous swelling and profound neuronal damages. Upregulation of nNOS expression is seen in both the dorsal and ventral horns of the spinal cord exhibiting cord pathology. At the ultrastructural level, exudation of lanthanum is seen within the endothelial cell cytoplasm and occasionally in the basal lamina. Pretreatment with low doses of HOE-140 (0. 1mg to 1mg/kg, i.v.) 30 min prior to SCI significantly enhanced the SCBF and reduced the BSCB disruption, edema formation, nNOS upregulation and cell injury. However, HOE-140 in doses ranging from 2mg to 5mg/kg, i.v. did not induce significant neuroprotection. These observations are the first to suggest that bradykinin B2 receptors pl

5-Hydroxytryptophan (5-HTP), a precursor of serotonin, is therapeutically used for several psychiatric disorders such as anxiety and depression in the clinic. However, severe side effects, including abnormal mental functions, behavioral disturbances and intolerance are associated with this treatment. 5-HTP-induced elevation of plasma and brain serotonin levels may affect blood-brain barrier (BBB) breakdown, edema formation and regional cerebral blood flow (CBF) disturbances. Breakdown of BBB to serum proteins leads to vasogenic brain edema formation and cellular injuries. However, 5-HTP-neurotoxicity is still not well known. In this investigations 5-HTP induced elevation of endogenous plasma and brain serotonin levels and its effect on BBB breakdown, edema formation neuronal injuries was examined in a rat model. Furthermore, potential role of oxidative stress and nitric oxide (NO) was evaluated. In addition, several neurochemical agents such as p-CPA (5-HT synthesis inhibitor) indomethacin (prostaglandin synthase inhibitor), diazepam (ant stress drug), cyproheptadine, ketanserin (5-HT2 receptor antagonists) and vinblastine (inhibitor of microtubule function) were examined on 5-HT neurotoxicity. Our observations suggest that 4h after 5-HTP administrations, the endogenous serotonin levels increased by fourfold (150mg/kg) in the plasma and brain associated with profound hyperthermia (+3.86 +/- 0.24 degrees C, oxidative stress and NO upregulation. Breakdown of the BBB to Evans blue albumin (EBA) in 8 brain regions and to ([131])Iodine in 14 brain regions was observed. The CBF exhibited marked reduction in all the brain regions examined. Brain edema and cellular injuries are present in the areas associated with BBB disruption. Drug treatments reduced the BBB breakdown, edema formation NO production and brain pathology. These observations are the first to point out that 5-HTP-neurotoxicity caused by BBB breakdown, edema formation and NO production is instrumental in causi

Spinal cord injury (SCI) is a devastating disease inflicting lifetime disability to the victims. Military personnel are quite often victims of SCI for which no suitable therapeutic strategies have been developed so far. The main reason for SCI induced disability is loss of neural connections below and above the lesion site causing motor paralysis and somatosensory disturbances Loss of neuronal connections thwart spinal cord conduction resulting in motor function disability. To enhance spinal cord conduction grafting of peripheral nerves, implant of hydrogels filled with neuroprotective drugs is used but so far, no satisfactory results re achieved. In this regards implants of microelectrode for enhancing tissue connectivity is suggested that is still under experimental state. We have used titanium implant with or without TiO2 nanowires in a focal spinal cord injury and studies spinal cord pathology and motor function. In addition, we also combined with nanowired delivery of a potential neuroprotective drug DL-3-n-butylphthalide (DL-NBP) to the spinal cord in a rat model. Our observations show that a combination of titanium implant with nanowired delivery of DL-NBP induces superior neuroprotection and enhance motor functions after SCI. This treatment also restored blood-spinal cord barrier (BSCB) function and reduces edema formation and cell injury after SCI, not reports earlier.

There is a growing trend of hypertension among military and civilian populations due to lifetime stressful situations. If hypertension is uncontrolled it leads to development of diabetes and serious neurological complications. Most of the World populations live in temperate zone across the World. Thus, a possibility exists that these hypertensive and diabetic people may have external heat as potential risk factors for brain damage. We have seen brain edema and brain damage following exposure to heat stress at 38 degrees C for 4h. A possibility exists that heat exposure in diabetic-hypertensive (DBHY) cases exacerbates exacerbation of brain pathology and edema formation. This hypothesis is examined in a rat model. The role of nitric oxide (NO) in exacerbation of HS-induced brain pathology was also evaluated using nitric oxide synthase (NOS) immunoreactivity. Hypertensive rats (produced by two-kidney one clip (2K1C) method) were made diabetic with streptozotocine (50 mg/kg, i.p./day for 3 days) treatment. After 6 weeks, DBHY rats show 20-30 mM/L Blood Glucose and hypertension (180-200 mmHg). Subjection of these rats to 4h HS resulted in six- to eightfold higher BBB breakdown, brain edema formation and brain pathology. At this time, neuronal or inducible NOS expression was four- to sixfold higher in DBHY rats compared to controls. Interestingly, iNOS expression was higher than nNOS in DBHY rats. Cerebrolysin in high doses (10-mL/kg, i.v. instead of 5-mL/kg) induced significant neuroprotection and downregulation of nNOS and iNOS in DBHY animals whereas normal animals need only 5-mL/kg doses for this purpose. Our observations demonstrate that co-morbidly factors exacerbate brain damage in HS through NOS expression and require double dose of cerebrolysin for neuroprotection as compared to normal rats, not reported earlier.

Several lines of evidences show that anesthetics influence neurotoxicity and neuroprotection. The possibility that different anesthetic agents potentially influence the pathophysiological and functional outcome following neurotrauma was examined in a rat model of concussive head injury (CHI). The CHI was produced by an impact of 0.224N on the right parietal bone by dropping a weight of 114.6g from a 20cm height under different anesthetic agents, e.g., inhaled ether anesthesia or intraperitoneally administered ketamine, pentobarbital, equithesin or urethane anesthesia. Five hour CHI resulted in profound volume swelling and brain edema formation in both hemispheres showing disruption of the blood-brain barrier (BBB) to Evans blue and radio-iodine. A marked decrease in the cortical CBF and a profound increase in plasma or brain serotonin levels were seen at this time. Neuronal damages were present in several parts of the brain. These pathological changes were most marked in CHI under ether anesthesia followed by ketamine (35mg/kg, i.p.), pentobarbital (50 mg/kg, i.p.), equithesin (3 mL/kg, i.p.) and urethane (1 g/kg, i.p.). The functional outcome on Rota Rod performances or grid walking tests was also most adversely affected after CHI under ether anesthesia followed by pentobarbital, equithesin and ketamine. Interestingly, the plasma and brain serotonin levels strongly correlated with the development of brain edema in head injured animals in relation to different anesthetic agents used. These observations suggest that anesthetic agents are detrimental to functional and pathological outcomes in CHI probably through influencing the circulating plasma and brain serotonin levels, not reported earlier. Whether anesthetics could also affect the efficacy of different neuroprotective agents in CNS injuries is a new subject that is currently being examined in our laboratory.

Introduction/Rational: Traumatic injuries to the central nervous system (CNS) occurring at cold or hot environments may affect the pathological outcome. In addition, this is not known whether injuries at these ambient temperatures may also affect the therapeutic potential of the drug treatments. Military personnel engaged in combat operations are often exposed to high environmental heat and thus under such situations if they are inflicted with trauma to the CNS their pathological outcome and drug therapy requires further investigation. In this investigation pathology and pharmacology of a focal spinal cord injury (SCI) at high environment was examined in a model experiment. Method/Approach: SCI was produced in Equithesin anesthetized rats either at room temperature (21 ± 1°C) or animals exposed to 38°C 1 h daily for 1 week by making a longitudinal incision (4 mm long and 2 mm deep) of the right dorsal horn of the T10-11 segments. In separate groups, Cerebrolsyin (2.5 ml or 5 ml/kg; Ever NeuroPharma, Austria) either as such or with TiO2 nanowired formulations was delivered intravenously 4 and 8 after SCI. After 48 h SCI blood-spinal cord barrier (BSCB), edema and neuronal injuries were examined. Uninjured animals at room or hot temperatures served as controls. Results/Effects: A focal SCI inflicted at hot environment resulted in marked exacerbation of BSCB breakdown to Evans blue albumin, edema formation and neuronal injuries as compared to identical SCI at room temperature. Treatment with 2.5 ml/kg cerebrolysin resulted in good neuroprotection in SCI at room temperature. However, either TiO2 nanowired cerebrolysin (2.5 ml) or higher dose of the drug (5 ml/kg) is needed to induce significant neuroprotection in SCI at inflicted at hot environment. TiO2 nanowires alone or TiO2 nanowired cerebrolysin did not influence cord pathology in normal animals at room temperature or at hot environment. Conclusions/Limitations: These observations are the first to demonstrate that, Meeting Abstract: 0009

Introduction/Rational: Military personnel are highly vulnerable to concussive head injury (CHI) during combat operations resulting in long-term disability. Since no suitable treatments are available novel therapeutic strategies using combination therapy is needed. Since, stem cells and/or neurotrophic factors are shown to induce neuroprotection in central nervous system (CSN) injuries and nanodelivery of therapeutic agents have superior effects on neuroprotection in brain injury, in this investigation we used nanowired delivery of mesenchymal stem cells (MSCs) together with a multimodal drug cerebrolysin- a powerful combination of various neurotrophic factors and active peptide fragments in CHI to induce neuroprotection in CHI. Method/Approach: CHI was inflicted in rats using a weight drop of 114.6 g on the right parietal skull under Equithesin anesthesia from a 20 cm height causing an impact of 0.224 N and mimic the “counter-coup” phenomenon as seen 48 h after the primary insult. In separate groups, commercially available MSCs (1 million cells) in combination with Cerebrolsyin (2.5 ml/kg; Ever NeuroPharma, Austria) either as such or with TiO2 nanowired formulations were delivered intravenously 4 and 8 after CHI. After 48 h CHI blood-brain barrier (BBB) to Evans blue and radioiodine, brain edema and neuronal injuries were examined. Results/Effects: A focal CHI induced massive breakdown of the BBB to Evans blue albumin and [131]-Iodine and volume swelling at 48 h that was significantly higher in the left hemisphere as compared to the right side. Neuronal damages using Nissl staining was also prominent in the cortex, hippocampus, thalamus and hypothalamus in the left side. Treatment with TiO2 nanowired MSCs and cerebrolysin resulted in significant reduction in brain pathology that was seen in both the right and left hemispheres. Whereas, normal MSCs and cerebrolysin were able to reduce brain pathology largely in the right side only. Conclusions/Limitations: These obse, Meeting Abstract: 0008

Introduction/Rational: Military personnel engaged in combat operation are often exposed to desert storm resulting in silica dust (SiO2 nanoparticles) intoxication. In addition, combat stress, sleep deprivation and continuous attention for enemy group results in mild to moderate hypertension. Under such situations, any traumatic brain or spinal cord injury could result in massive brain pathology due to stress induced hypertension and possibly SiO2 nanoparticles intoxication. However, effects of trauma in hypertension and SiO2 intoxication are still not well known. In present study we investigated the effects of hypertension and SiO2 intoxication of the pathophysiology of traumatic brain injury (TBI). Method/Approach: Male Wistar rats (250-300 g) were made renal hypertensive by 2kidney 1clip (2K1C) procedure allowing mean arterial blood pressure (MABP) reaching 180 ± 8 torr over 6 weeks. These hypertensive rats were exposed to SiO2NPs (40-50 nm) once daily (50 mg/kg, i.p.) for 8 days. On the 9th day these hypertensive and SiO2NPs intoxicated animals were subjected to TBI under anesthesia by making an incision (3 mm long and 2.5 mm deep) on the right parietal cerebral cortex after opening the skull (4mmOD) on both sides. The animas were allowed to survive 48 h after TBI. Results/Effects: TBI in hypertensive and SiO2 nanoparticles intoxicated rats showed 4-to-6 fold higher breakdown of the blood-brain barrier (BBB) to Evans blue albumin (EBA) and [131]-Iodine, edema formation and neuronal injuries as compared to TBI in normal animals at 48 h. Treatment with a multimodal drug Cerebrolysin-containing balanced composition of neurotrophic factors and active peptide fragments (10 ml/kg, i.v.) started 4 h after TBI followed by 4 injections at every 8 h markedly reduced brain pathologies. Whereas only 5 ml/kg of the drug is needed to achieve identical neuroprotection in normal rats after TBI. Conclusions/Limitations: These observations are the first to show that a combination, Meeting Abstract: 0010