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Concussive head injury (CHI) often associated with military personnel, soccer players and related sports personnel leads to serious clinical situation causing lifetime disabilities. About 3-4k head injury per 100k populations are recorded in the United States since 2000-2014. The annual incidence of concussion has now reached to 1.2% of population in recent years. Thus, CHI inflicts a huge financial burden on the society for rehabilitation. Thus, new efforts are needed to explore novel therapeutic strategies to treat CHI cases to enhance quality of life of the victims. CHI is well known to alter endogenous balance of excitatory and inhibitory amino acid neurotransmitters in the central nervous system (CNS) leading to brain pathology. Thus, a possibility exists that restoring the balance of amino acids in the CNS following CHI using therapeutic measures may benefit the victims in improving their quality of life. In this investigation, we used a multimodal drug Cerebrolysin (Ever NeuroPharma, Austria) that is a well-balanced composition of several neurotrophic factors and active peptide fragments in exploring its effects on CHI induced alterations in key excitatory (Glutamate, Aspartate) and inhibitory (GABA, Glycine) amino acids in the CNS in relation brain pathology in dose and time-dependent manner. CHI was produced in anesthetized rats by dropping a weight of 114.6g over the right exposed parietal skull from a distance of 20cm height (0.224N impact) and blood-brain barrier (BBB), brain edema, neuronal injuries and behavioral dysfunctions were measured 8, 24, 48 and 72h after injury. Cerebrolysin (CBL) was administered (2.5, 5 or 10mL/kg, i.v.) after 4-72h following injury. Our observations show that repeated CBL induced a dose-dependent neuroprotection in CHI (5-10mL/kg) and also improved behavioral functions. Interestingly when CBL is delivered through TiO

Military personnel are vulnerable to environmental or industrial exposure of engineered nanoparticles (NPs) from metals. Long-term exposure of NPs from various sources affect sensory-motor or cognitive brain functions. Thus, a possibility exists that chronic exposure of NPs affect blood-brain barrier (BBB) breakdown and brain pathology by inducing oxidative stress and/or nitric oxide production. This hypothesis was examined in the rat intoxicated with Ag, Cu or Al (50-60nm) nanoparticles (50mg/kg, i.p. once daily) for 7 days. In these NPs treated rats the BBB permeability, brain edema, neuronal nitric oxide synthase (nNOS) immunoreactivity and brain oxidants levels, e.g., myeloperoxidase (MP), malondialdehyde (MD) and glutathione (GT) was examined on the 8th day. Cu and Ag but not Al nanoparticles increased the MP and MD levels by twofold in the brain although, GT showed 50% decline. At this time increase in brain water content and BBB breakdown to protein tracers were seen in areas exhibiting nNOS positive neurons and cell injuries. Pretreatment with insulin like growth factor-1 (IGF-1) in high doses (1μg/kg, i.v. but not 0.5μg/kg daily for 7 days) together with NPs significantly reduced the oxidative stress, nNOS upregulation, BBB breakdown, edema formation and cell injuries. These novel observations demonstrate that (i) NPs depending on their metal constituent (Cu, Ag but not Al) induce oxidative stress and nNOS expression leading to BBB disruption, brain edema and cell damage, and (ii) IGF-1 depending on doses exerts powerful neuroprotection against nanoneurotoxicity, not reported earlier.

Military personnel are often exposed to high altitude (HA, ca. 4500-5000m) for combat operations associated with neurological dysfunctions. HA is a severe stressful situation and people frequently use methamphetamine (METH) or other psychostimulants to cope stress. Since military personnel are prone to different kinds of traumatic brain injury (TBI), in this review we discuss possible effects of METH on concussive head injury (CHI) at HA based on our own observations. METH exposure at HA exacerbates pathophysiology of CHI as compared to normobaric laboratory environment comparable to sea level. Increased blood-brain barrier (BBB) breakdown, edema formation and reductions in the cerebral blood flow (CBF) following CHI were exacerbated by METH intoxication at HA. Damage to cerebral microvasculature and expression of beta catenin was also exacerbated following CHI in METH treated group at HA. TiO2-nanowired delivery of H-290/51 (150mg/kg, i.p.), a potent chain-breaking antioxidant significantly enhanced CBF and reduced BBB breakdown, edema formation, beta catenin expression and brain pathology in METH exposed rats after CHI at HA. These observations are the first to point out that METH exposure in CHI exacerbated brain pathology at HA and this appears to be related with greater production of oxidative stress induced brain pathology, not reported earlier.

Military personnel are often exposed to high environmental heat associated with industrial or ambient abundance of nanoparticles (NPs) affecting brain function. We have shown that engineered metal NPs Ag and Cu exacerbate hyperthermia induced brain pathology. Thus, exploration of novel drug therapy is needed for effective neuroprotection in heat stroke intoxicated with NPs. In this investigation neuroprotective effects of cerebrolysin, a balanced composition of several neurotrophic factors and active peptides fragments exhibiting powerful antioxidant and anti-ischemic effects was examined in heat stroke after NPs intoxication. In addition, its efficacy is compared to currently used drugs in post-stroke therapies in clinics. Thus, levertiracetam, pregabalin, topiramat and valproate were compared in standard doses with cerebrolysin in heat stroke intoxicated with Cu or Ag NPs (50-60nm, 50mg/kg, i.p./day for 7 days). Rats were subjected to 4h heat stress (HS) in a biological oxygen demand incubator at 38°C (Relative Humidity 45-47%; Wind velocity 22.4-25.6cm/s) that resulted in profound increase in oxidants Luminol, Lucigenin, Malondialdehyde and Myeloperoxidase, and a marked decrease in antioxidant Glutathione. At this time severe reductions in the cerebral blood flow (CBF) was seen together with increased blood-brain barrier (BBB) breakdown and brain edema formation. These pathophysiological responses were exacerbated in NPs treated heat-stressed animals. Pretreatment with cerebrolysin (2.5mL/kg, i.v.) once daily for 3 days significantly attenuated the oxidative stress, BBB breakdown and brain edema and improved CBF in the heat stressed group. The other drugs were least effective on brain pathology following heat stroke. However, in NPs treated heat stressed animals 5mL/kg conventional cerebrolysin and 2.5mL/kg nanowired cerebrolysin is needed to attenuate oxidative stress, BBB breakdown, brain edema and to improve CBF. Interestingly, the other drugs even in higher doses used are unable to alter brain pathologies in NPs and heat stress. These observations are the first to demonstrate that cerebrolysin is the most superior antioxidant and anti-ischemic drug in NPs exposed heat stroke, not reported earlier.

Nanoparticles affect blood-brain barrier (BBB) and brain edema formation resulting in sensory-motor dysfunction. Exposure of Mn nanoparticles from industrial sources in humans could target basal ganglia resulting in Parkinson's disease. In present investigation, Mn exposure on brain pathology in a rat model was examined. Rats received Mn nanoparticles (30-40nm size) in a dose of 10 or 20mg/kg, i.p. once daily for 7 days and behavioral dysfunctions on Rota Rod performance, inclined plane angle and grid-walking tests as well as gait performances were examined. In addition, BBB breakdown to Evans blue and radioiodine, brain edema formation and neural injuries were also evaluated. Mn nanoparticles treated rats exhibited cognitive and motor dysfunction on the 8th day. At this time, BBB disruption, reduction in cerebral blood flow (CBF), brain edema formation and brain pathology were most marked in the sensory-motor cortex, hippocampus, caudate putamen, cerebellum and thalamus followed by hypothalamus, pons, medulla and spinal cord. In these brain areas, neuronal injuries using Nissl staining was clearly seen. These effects of Mn nanoparticle are dose dependent. These results are the first to demonstrate that Mn nanoparticles induce selective brain pathology resulting in cognitive and motor dysfunction, not reported earlier.

Oxidative stress plays an important role in neuronal injuries after cardiac arrest. Increased production of carbon monoxide (CO) by the enzyme hemeoxygenase (HO) in the brain is induced by the oxidative stress. HO is present in the CNS in two isoforms, namely the inducible HO-1 and the constitutive HO-2. Elevated levels of serum HO-1 occurs in cardiac arrest patients and upregulation of HO-1 in cardiac arrest is seen in the neurons. However, the role of HO-2 in cardiac arrest is not well known. In this review involvement of HO-1 and HO-2 enzymes in the porcine brain following cardiac arrest and resuscitation is discussed based on our own observations. In addition, neuroprotective role of methylene blue- an antioxidant dye on alterations in HO under in cardiac arrest is also presented. The biochemical findings of HO-1 and HO-2 enzymes using ELISA were further confirmed by immunocytochemical approach to localize selective regional alterations in cardiac arrest. Our observations are the first to show that cardiac arrest followed by successful cardiopulmonary resuscitation results in significant alteration in cerebral concentrations of HO-1 and HO-2 levels indicating a prominent role of CO in brain pathology and methylene blue during CPR followed by induced hypothermia leading to superior neuroprotection after return of spontaneous circulation (ROSC), not reported earlier.

Sleep deprivation (SD) is common in military personnel engaged in combat operations leading to brain dysfunction. Military personnel during acute or chronic SD often prone to traumatic brain injury (TBI) indicating the possibility of further exacerbating brain pathology. Several lines of evidence suggest that in both TBI and SD alpha-melanocyte-stimulating hormone (α-MSH) and brain-derived neurotrophic factor (BDNF) levels decreases in plasma and brain. Thus, a possibility exists that exogenous supplement of α-MSH and/or BDNF induces neuroprotection in SD compounded with TBI. In addition, mesenchymal stem cells (MSCs) are very portent in inducing neuroprotection in TBI. We examined the effects of concussive head injury (CHI) in SD on brain pathology. Furthermore, possible neuroprotective effects of α-MSH, MSCs and neurotrophic factors treatment were explored in a rat model of SD and CHI. Rats subjected to 48h SD with CHI exhibited higher leakage of BBB to Evans blue and radioiodine compared to identical SD or CHI alone. Brain pathology was also exacerbated in SD with CHI group as compared to SD or CHI alone together with a significant reduction in α-MSH and BDNF levels in plasma and brain and enhanced level of tumor necrosis factor-alpha (TNF-α). Exogenous administration of α-MSH (250μg/kg) together with MSCs (1×10

Spinal cord evoked potentials (SCEP) are good indicators of spinal cord function in health and disease. Disturbances in SCEP amplitudes and latencies during spinal cord monitoring predict spinal cord pathology following trauma. Treatment with neuroprotective agents preserves SCEP and reduces cord pathology after injury. The possibility that cerebrolysin, a balanced composition of neurotrophic factors improves spinal cord conduction, attenuates blood-spinal cord barrier (BSCB) disruption, edema formation, and cord pathology was examined in spinal cord injury (SCI). SCEP is recorded from epidural space over rat spinal cord T9 and T12 segments after peripheral nerves stimulation. SCEP consists of a small positive peak (MPP), followed by a prominent negative peak (MNP) that is stable before SCI. A longitudinal incision (2mm deep and 5mm long) into the right dorsal horn (T10 and T11 segments) resulted in an immediate long-lasting depression of the rostral MNP with an increase in the latencies. Pretreatment with either cerebrolysin (CBL 5mL/kg, i.v. 30min before) alone or TiO

The possibility that stress associated with chronic forced swim (FS) may exacerbate methamphetamine (METH) neurotoxicity was examined in a rat model. Rats were subjected to FS in a pool (30 °C) for 15 min daily for 8 days. Control rats were kept at room temperature. METH was administered (9 mg/kg, s.c.) in both control and FS rats and allowed to survive 4 h after the drug injection. METH in FS rats exacerbated BBB breakdown to Evans blue albumin (EBA) by 150 to 220% and [131]-Iodine by 250 to 380% as compared to naive rats after METH. The METH-induced BBB leakage was most pronounced in the cerebral cortex followed by the hippocampus, cerebellum, thalamus, and hypothalamus in both FS and naive rats. The regional BBB changes were associated with a reduction in the local cerebral blood flow (CBF). Brain edema was also higher by 2 to 4% in FS rats after METH than in naive animals. Neuronal and glial cell injuries were aggravated by threefold to fivefold after METH in FS than the control group. Pretreatment with ondansetron (1 mg/kg, i.p.) 30 min before METH injection in naive rats reduced the brain pathology and improved the CBF. However, TiO2-nanowired delivery of ondansetron (1 mg/kg, i.p.) was needed to reduce METH-induced brain damage, BBB leakage, reduction in CBF, and edema formation in FS. Taken together, these observations are the first to show that METH exacerbates BBB breakdown leading to neurotoxicity in FS animals. This effect of METH-induced BBB breakdown and brain pathology in naive and FS rats is attenuated by ondansetron treatment indicating an involvement of 5-HT3 receptors, not reported earlier.

The possibility that traumatic brain injury (TBI) occurring in a cold environment exacerbates brain pathology and oxidative stress was examined in our rat model. TBI was inflicted by making a longitudinal incision into the right parietal cerebral cortex (2 mm deep and 4 mm long) in cold-acclimatized rats (5 °C for 3 h daily for 5 weeks) or animals at room temperature under Equithesin anesthesia. TBI in cold-exposed rats exhibited pronounced increase in brain lucigenin (LCG), luminol (LUM), and malondialdehyde (MDA) and marked pronounced decrease in glutathione (GTH) as compared to identical TBI at room temperature. The magnitude and intensity of BBB breakdown to radioiodine and Evans blue albumin, edema formation, and neuronal injuries were also exacerbated in cold-exposed rats after injury as compared to room temperature. Nanowired delivery of H-290/51 (50 mg/kg) 6 and 8 h after injury in cold-exposed group significantly thwarted brain pathology and oxidative stress whereas normal delivery of H-290/51 was neuroprotective after TBI at room temperature only. These observations are the first to demonstrate that (i) cold aggravates the pathophysiology of TBI possibly due to an enhanced production of oxidative stress, (ii) and in such conditions, nanodelivery of antioxidant compound has superior neuroprotective effects, not reported earlier.

Neprilysin (NPL), the rate-limiting enzyme for amyloid beta peptide (AβP), appears to play a crucial role in the pathogenesis of Alzheimer's disease (AD). Since mesenchymal stem cells (MSCs) and/or cerebrolysin (CBL, a combination of neurotrophic factors and active peptide fragments) have neuroprotective effects in various CNS disorders, we examined nanowired delivery of MSCs and CBL on NPL content and brain pathology in AD using a rat model. AD-like symptoms were produced by intraventricular (i.c.v.) administration of AβP (1-40) in the left lateral ventricle (250 ng/10 μl, once daily) for 4 weeks. After 30 days, the rats were examined for NPL and AβP concentrations in the brain and related pathology. Co-administration of TiO2-nanowired MSCs (106 cells) with 2.5 ml/kg CBL (i.v.) once daily for 1 week after 2 weeks of AβP infusion significantly increased the NPL in the hippocampus (400 pg/g) from the untreated control group (120 pg/g; control 420 ± 8 pg/g brain) along with a significant decrease in the AβP deposition (45 pg/g from untreated control 75 pg/g; saline control 40 ± 4 pg/g). Interestingly, these changes were much less evident when the MSCs or CBL treatment was given alone. Neuronal damages, gliosis, and myelin vesiculation were also markedly reduced by the combined treatment of TiO2, MSCs, and CBL in AD. These observations are the first to show that co-administration of TiO2-nanowired CBL and MSCs has superior neuroprotective effects in AD probably due to increasing the brain NPL level effectively, not reported earlier.

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 TiO

Alzheimer's disease (AD) is estimated to be afflicting over 55 millions of individual worldwide in 2018-19 for which no suitable clinical therapeutic measures have been developed so far. Thus, there is an urgent need to explore novel therapeutic strategies using nanodelivery of drugs and agents either alone or in combination for superior neuroprotection in AD and enhanced quality of life of the affected individuals. There are reports that AD is often associated with diminished neurotrophic factors and neprilysin together with enhancement of phosphorylated Tau (p-Tau) within the brain and in the cerebrospinal fluid (CSF). Thus, studies aiming to enhance neurotrophic factors and neprilysin together with neutralizing p-Tau within the central nervous system (CNS) may alleviate brain pathology in AD. In this review these strategies are discussed using nanotechnological approaches largely based on our own investigations in relation to current literature in the field.

Parkinson's disease (PD) is affecting10 million people worldwide for which no suitable cure has been developed so far. Roughly, about two people per thousand populations are affected with PD like symptoms especially over the age of 50. About 1% of the populations above 60 years suffer from PD-like disease. The prevalence of the disease is increasing over the years, and future projections by 2020 could be 12-14 millions people affected by the disease. Thus, exploration of suitable therapeutic measures is the need of the hour to enhance quality of the life of PD patients. PD induced brain pathology includes loss of dopaminergic neurons in the substantia niagra that could later extends to other cortical regions causing loss of voluntary motor control. Deposition of α-synuclein in the brain further leads to neurodegeneration. However, the exact cause of PD is still unknown. It appears that breakdown of the blood-brain barrier (BBB) and leakage of serum component into the brain could lead to neurodegeneration in PD. Thus, novel treatment strategies that are able to restore BBB breakdown and enhance neuronal plasticity and neuroregeneration in PD could be effective in future therapy. With the advancement of nanotechnology, it is worthwhile to understand the role of nanodelivery of selected agents in PD to enhance neuroprotection. In this review new role of BBB, brain edema, and neuropathology in PD is discussed. In addition, superior neuroprotection induced by nanowired delivery of a multimodal drug cerebrolysin in PD is summarized based on our own investigations.

Concussive head injury (CHI) is quite prevalent in military personnel leading to lifetime disability in more than 85% of cases. Other reasons of CHI include motor vehicle accident, fall or blunt trauma under various conditions. In United States of America (USA) alone more than 150k cases of head injury are added every year for which no suitable therapeutic strategies are still available. Thus, there is a need to expand our knowledge in treating CHI cases with novel therapeutic measures to enhance the quality of life of head injury victims. With recent advancements in nanodelivery of drugs for superior neuroprotective effects in neurological diseases, our laboratory is engaged in understanding the role of nanowired delivery of suitable drugs in treating CHI and other neurodegenerative diseases. DL-3-n-butylphthalide (NBP) is an extract of Chinese celery and is able to induce profound neuroprotection following ischemic stroke and other related neurological dysfunction. Thus, it is quite likely that synthetic NBP could have pronounced neuroprotective effects in CHI as well. We believe that nanodelivery of NBP have superior neuroprotection in CHI. In this review neuroprotective effects of nanowired delivery of NBP in CHI induced brain pathology is described. Our experimental observations show that nanowired delivery of NBP results in superior neuroprotection than the regular NBP in CHI. The probable mechanisms and functional significance of our finding in relation to military medicine is discussed based on our own investigations.

The blood-brain barrier (BBB) is a physiological regulator of transport of essential items from blood to brain for the maintenance of homeostasis of the central nervous system (CNS) within narrow limits. The BBB is also responsible for export of harmful or metabolic products from brain to blood to keep the CNS fluid microenvironment healthy. However, noxious insults to the brain caused by trauma, ischemia or environmental/chemical toxins alter the BBB function to small as well as large molecules e.g., proteins. When proteins enter the CNS fluid microenvironment, development of brain edema occurs due to altered osmotic balance between blood and brain. On the other hand, almost all neurodegenerative diseases and traumatic insults to the CNS and subsequent BBB dysfunction lead to edema formation and cell injury. To treat these brain disorders suitable drug therapy reaching their brain targets is needed. However, due to edema formation or only a focal disruption of the BBB e.g., around brain tumors, many drugs are unable to reach their CNS targets in sufficient quantity. This results in poor therapeutic outcome. Thus, new technology such as nanodelivery is needed for drugs to reach their CNS targets and be effective. In this review, use of nanowires as a possible novel tool to enhance drug delivery into the CNS in various disease models is discussed based on our investigations. These data show that nanowired delivery of drugs may have superior neuroprotective ability to treat several CNS diseases effectively indicating their role in future therapeutic strategies.

Nanoscience provides us with new opportunities to develop nanotechnologies for treating, in particular, central nervous system disorders such as Alzheimer disease and multiple sclerosis. From a methodological point of view, it is challenging to deliver drugs effectively across the blood-brain barrier and blood-cerebrospinal fluid barrier. Our 10-year data and reports from both in vivo and in vitro studies, however, have consistently proved that therapeutic drugs of different types can be generally loaded in/on the nanocarriers for targeted and programmable deliveries to the central nervous system with a high degree of efficacy. This chapter presents a protocol for the synthesis of biocompatible titanate nanofibers as low-cost drug delivery cargos. In addition, a procedure for loading the neuroprotective agent Cerebrolysin onto the nanofibers is briefly described. Finally, experimental observations on the use of nanodrug delivery for superior neuroprotective effects of Cerebrolysin in traumatic brain injury are given as a proof of concept as compared to normal drug alone.

More than 5.5 million Americans of all ages are suffering from Alzheimer's disease (AD) till today for which no suitable therapy has been developed so far. Thus, there is an urgent need to explore novel therapeutic measures to contain brain pathology in AD. The hallmark of AD includes amyloid-beta peptide (AβP) deposition and phosphorylation of tau in AD brain. Recent evidences also suggest a marked decrease in neurotrophic factors in AD. Thus, exogenous supplement of neurotrophic factors could be one of the possible ways for AD therapy. Human postmortem brain in AD shows alterations in histamine receptors as well, indicating an involvement of the amine in AD-induced brain pathology. In this review, we focused on role of histamine 3 and 4 receptor-modulating drugs in the pathophysiology of AD. Moreover, antibodies to histamine and tau appear to be also beneficial in reducing brain pathology, blood-brain barrier breakdown, and edema formation in AD. Interestingly, TiO

Previous studies from our laboratory show that intraperitoneal injections of 1-metyl-4-phenyl-1,2,3,6-tetrahydropyridin (MPTP, 20 mg/kg) daily within 2-h intervals for 5 days in mice induce Parkinson’s disease (PD)-like symptoms on the 8th day. A significant decrease in dopamine (DA) and its metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) along with a marked decrease in the number of tyrosine hydroxylase (TH)-positive cells in the substantia nigra pars compacta (SNpc) and striatum (STr) confirms the validity of this model for studying PD. Since cerebrolysin (CBL) is a well-balanced composition of several neurotrophic factors and active peptide fragments, in the present investigation we examined the timed release of CBL using titanate nanospheres (TiNS) in treating PD in our mouse model. Our observations show that TiNS-CBL (in a dose of 3 ml/kg, i.v.) given after 2 days of MPTP administration for 5 days resulted in a marked increase in TH-positive cells in the SNpc and STr as compared to normal CBL. Also, TiNS-CBL resulted in significantly higher levels of DA, DOPAC, and HVA in SNpc and STr on the 8th day as compared to normal CBL therapy. TiNS-CBL also thwarted increased α-synuclein levels in the brain and in the cerebrospinal fluid (CSF) as well as neuronal nitric oxide synthase (nNOS) in the in PD brain as compared to untreated group. Behavioral function was also significantly improved in MPTP-treated animals that received TiNS-CBL. These observations are the first to demonstrate that timed release of TiNS-CBL has far more superior neuroprotective effects in PD than normal CBL.

DL-3-n-butylphthalide (DL-NBP) is one of the constituents of Chinese celery extract that is used to treat stroke, dementia, and ischemic diseases. However, its role in traumatic brain injury is less well known. In this investigation, neuroprotective effects of DL-NBP in concussive head injury (CHI) on brain pathology were explored in a rat model. CHI was inflicted in anesthetized rats by dropping a weight of 114.6 g from a height of 20 cm through a guide tube on the exposed right parietal bone inducing an impact of 0.224 N and allowed them to survive 4 to 24 h after the primary insult. DL-NBP was administered (40 or 60 mg/kg, i.p.) 2 and 4 h after injury in 8-h survival group and 8 and 12 h after trauma in 24-h survival group. In addition, TiO

Nanoparticles from the environment or through industrial sources can induce profound alterations in human health, often leading to brain dysfunction. However, it is still unclear whether nanoparticle intoxication could also alter the physiological or pathological responses of additional brain injury, stress response or disease processes. Military personals engaged in combat or peacekeeping operations are often exposed to nanoparticles from various environmental sources, e.g., Ag, Cu, Si, C, Al. In addition, these military personals are often exposed to high environmental heat, or gun and missle explosion injury leading to head or spinal trauma. Thus it is likely that additional CNS injury or stress-induced pathophysiological processes are influenced by nanoparticle intoxication. In this situation, when a combination of nanoparticles and central nervous system (CNS) injury or stress exist together, drug therapy needed to correct these anomalies may not work as effectively as in normal situation. Previous studies from our laboratory show that nanoparticle-intoxicated animals when subjected to hyperthermia resulted in exacerbation of brain pathology. In these animals, antioxidant compounds, e.g., H-290/51 that inhibits free radical formation and induces marked neuroprotection in normal rats after heat stress, failed to protect brain damage when a combination of nanoparticles and heat exposure was used. However, nanowired H-290/51 resulted in better neuroprotection in nanoparticles intoxicated animals after heat stress. Interestingly, high doses of the normal compound induced some neuroprotection in these nanoparticle-treated, heat-stressed rats. These observations suggest that a combination of nanoparticles and heat stress is dangerous and in such situations modification of drug dosage is needed to achieve comparable neuroprotection. In this review possible mechanisms of nanoparticle-induced exacerbation of heat induced neurotoxicity and brain protection achieved by nanowired drug delivery is discussed that is largely based on our own investigations.

The possibility that chronic exposure of nanoparticles may alter stress reaction and brain pathology following hyperthermia was examined in a rat model. Engineered nanoparticles from Ag or Cu (approximately equal to 50-60 nm) were administered (30 mg/kg, i.p.) once daily for 1 week in young male rats. On the 8th day these animals were subjected to 4 h heat stress at 38 degrees C in a BOD incubator. In these animals stress symptoms, blood-brain barrier (BBB) permeability, cognitive and motor functions and brain pathology were examined. Subjection of nanoparticle treated rats to heat stress showed exacerbation of stress symptoms i.e., hyperthermia, salivation and prostration and exhibited greater BBB disruption, brain edema formation, impairment of cognitive and motor functions and brain damage compared to normal animals. This enhanced brain pathology in heat stress was most marked in animals that received Ag nanoparticles compared to Cu treatment. Treatment with antioxidant compound H-290/51 either 30 min or 60 min after heat stress did not alter hyperthermia induce brain pathology in nanoparticle treated rats. Whereas, administration of nanowired-H-290/51 after 30 min or 60 min heat stress markedly attenuated BBB disruption, sensory motor function and brain pathology. These results suggest that chronic nanoparticles treatment exacerbate hyperthermia induced brain pathology that is significantly attenuated by nanowired but not normal H-290/51 compound. Taken together, our observations suggest that nano-wired drug delivery of H-290/51 is a promising approach to induce neuroprotection in hyperthermia induced brain pathology, not reported earlier.

Previous studies from our laboratory showed that topical application of growth hormone (GH) induced neuroprotection 5 h after spinal cord injury (SCI) in a rat model. Since nanodelivery of drugs exerts superior neuroprotective effects, a possibility exists that nanodelivery of GH will induce long-term neuroprotection after a focal SCI. SCI induces GH deficiency that is coupled with insulin-like growth factor-1 (IGF-1) reduction in the plasma. Thus, an exogenous supplement of GH in SCI may enhance the IGF-1 levels in the cord and induce neuroprotection. In the present investigation, we delivered TiO2-nanowired growth hormone (NWGH) after a longitudinal incision of the right dorsal horn at the T10–11 segments in anesthetized rats and compared the results with normal GH therapy on IGF-1 and GH contents in the plasma and in the cord in relation to blood-spinal cord barrier (BSCB) disruption, edema formation, and neuronal injuries. Our results showed a progressive decline in IGF-1 and GH contents in the plasma and the T9 and T12 segments of the cord 12 and 24 h after SCI. Marked increase in the BSCB breakdown, as revealed by extravasation of Evans blue and radioiodine, was seen at these time points after SCI in association with edema and neuronal injuries. Administration of NWGH markedly enhanced the IGF-1 levels and GH contents in plasma and cord after SCI, whereas normal GH was unable to enhance IGF-1 or GH levels 12 or 24 h after SCI. Interestingly, NWGH was also able to reduce BSCB disruption, edema formation, and neuronal injuries after trauma. On the other hand, normal GH was ineffective on these parameters at all time points examined. Taken together, our results are the first to demonstrate that NWGH is quite effective in enhancing IGF-1 and GH levels in the cord and plasma that may be crucial in reducing pathophysiology of SCI.

Military personnel are often subjected to sleep deprivation (SD) during combat operations. Since SD is a severe stress and alters neurochemical metabolism in the brain, a possibility exists that acute or long-term SD will influence blood-brain barrier (BBB) function and brain pathology. This hypothesis was examined in young adult rats (age 12 to 14 weeks) using an inverted flowerpot model. Rats were placed over an inverted flowerpot platform (6.5 cm diameter) in a water pool where the water levels are just 3 cm below the surface. In this model, animals can go to sleep for brief periods but cannot achieve deep sleep as they would fall into water and thus experience sleep interruption. These animals showed leakage of Evans blue in the cerebellum, hippocampus, caudate nucleus, parietal, temporal, occipital, cingulate cerebral cortices, and brain stem. The ventricular walls of the lateral and fourth ventricles were also stained blue, indicating disruption of the BBB and the blood-cerebrospinal fluid barrier (BCSFB). Breakdown of the BBB or the BCSFB fluid barrier was progressive in nature from 12 to 48 h but no apparent differences in BBB leakage were seen between 48 and 72 h of SD. Interestingly, rats treated with metal nanoparticles, e.g., Cu or Ag, showed profound exacerbation of BBB disruption by 1.5- to 4-fold, depending on the duration of SD. Measurement of plasma and brain serotonin showed a close correlation between BBB disruption and the amine level. Repeated treatment with the serotonin 5-HT3 receptor antagonist ondansetron (1 mg/kg, s.c.) 4 and 8 h after SD markedly reduced BBB disruption and brain pathology after 12 to 24 h SD but not following 48 or 72 h after SD. However, TiO2-nanowired ondansetron (1 mg/kg, s.c) in an identical manner induced neuroprotection in rats following 48 or 72 h SD. However, plasma and serotonin levels were not affected by ondansetron treatment. Taken together, our observations are the first to show that (i) SD could induce BBB disruption and brain pathology, (ii) nanoparticles exacerbate SD-induced brain damage, and (iii) serotonin 5-HT3 receptor antagonist ondansetron is neuroprotective in SD that is further potentiated byTiO2-nanowired delivery, not reported earlier.

Neurotoxicity caused by diverse psychostimulant drugs, for example, methamphetamine, 3,4-methylenedioxy-methamphetamine, cocaine or morphine is a cause of concern to human populations especially the young generation across the world. These recreational drugs affect brain function severely leading to addiction and brain pathology. Use of psychostimulants may induce breakdown of the blood-brain barrier to serum proteins resulting in adverse brain microenvironment, edema cell injury or eventually neuronal death. Thus, there is an urgent need to find out detailed mechanisms of psychostimulants-induced neurotoxicity in vivo models for suitable therapeutic strategies to induce neuroprotection and also to help de-addiction in clinical situations.In this review, psychostimulants drugs-induced neurotoxicity is discussed in view of recent literature and the financial burden it may pose on our society due to rehabilitation and de-addiction. Furthermore, experimental evidences of drug-induced neuroprotection are also discussed.Use of in vivo models of neurotoxicity caused by psychostimulants is discussed based on author's own research and to find suitable drugs that could induce neuroprotection including nanodelivery. Furthermore, novel therapeutic agents for de-addiction and reducing neurotoxicity following psychostimulants administration are presented.

Spinal cord injury (SCI) is a serious clinical situation for which no suitable drug therapy exists. SCI often results in paraplegia or quadriplegia and, apart from the personal trauma leads to huge costs to society for rehabilitation or day-to-day life support. Sensory motor dysfunction following SCI is mainly a consequence of the slowly progressing cord pathology after primary injury that worsens over tine. Thus, almost all sensory and motor nerve control and pathways passing through spinal cord and reflexes are compromised in SCI patients. As a result their peripheral nervous system, autonomic nervous function and central nervous system regulations are adversely affected. Experiments carried out in our laboratory show that various therapeutic agents, if given within 10 to 30 minutes after primary SCI could correct morphological changes to a certain extent. In these rat models of SCI reduction in cord pathology, e.g., bloodspinal cord barrier (BSCB) breakdown, edema formation and cell injury by the neuroprotective agents that also limited sensory motor dysfunction and improved functional behavior. However, these drugs if given beyond 30 minutes after SCI showed a markedly reduced neuroprotective efficacy. Thus, new strategies are needed to enhance neuroprotection in SCI to prevent structural and functional changes over longer periods of time. To that end our laboratory has initiated a series of investigations in which nanowired delivery of various neurotherapeutic agents are applied after different time periods of SCI, that resulted in a much better outcome than with the parent compounds under identical conditions. The superior neuroprotective activity of nanowired compound delivery could be due to a reduced metabolism of active compounds in the central nervous system (CNS) or by sustained release of the drug for longer times. In addition, nanowired drugs may penetrate the CNS faster and could reach widespread areas once entering the spinal cord. Thus, nanowired drug delivery to treat SCI may have potential therapeutic value. These aspects of nanowired drug delivery to enhance neuroprotection in SCI are discussed in this review based on our own investigations.

The possibility that drugs attached to nanowires enhance their therapeutic efficacy was examined in a rat model of spinal cord injury (SCI). Three Acure compounds AP-173, AP-713 and AP-364 were tagged with TiO(2)-based nanowires (50-60 nm) and applied over the traumatized cord either 5 or 60 min after SCI in rats produced by a longitudinal incision into the right dorsal horn of the T10-11 segments under equithesin anaesthesia. Normal compounds were used for comparison. After 5 h SCI, behavioral outcome, blood-spinal cord barrier (BSCB) permeability, edema formation and cell injury were examined. Topical application of nanowired compound AP-713 (10 microg in 20 microL) when applied either 5 or 60 min after injury markedly attenuated behavioral dysfunction at 2-3 h after SCI and reduces BSCB disruption, edema formation and cord pathology at 5 h compared to other compounds. Whereas normal compounds applied at 5 min after injury (but not after 60 min) had some significant but less beneficial effects compared to their nanowired combinations. On the other hand, nanowires alone did not influence spinal cord pathology or motor function after SCI. Taken together, our results indicate that the nanowired-drug-delivery enhances the neuroprotective efficacy of drugs in SCI and reduces functional outcome compared to normal compounds even applied at a later stage following trauma, not reported earlier.

The possibility that drugs attached to innocuous nanowires enhance their delivery within the central nervous system (CNS) and thereby increase their therapeutic efficacy was examined in a rat model of spinal cord injury (SCI). Three compounds--AP173 (SCI-1), AP713 (SCI-2), and AP364 (SCI-5) (Acure Pharma, Uppsala, Sweden)--were tagged with TiO(2)-based nanowires using standard procedure. Normal compounds were used for comparison. SCI was produced by making a longitudinal incision into the right dorsal horn of the T10-T11 segments under Equithesin anesthesia. The compounds, either alone or tagged with nanowires, were applied topically within 5 to 10 min after SCI. In these rats, behavioral outcome, blood-spinal cord barrier (BSCB) permeability, edema formation, and cell injury were examined at 5 h after injury. Topical application of normal compounds in high quantity (10 microg in 20 microL) attenuated behavioral dysfunction (3 h after trauma), edema formation, and cell injury, as well as reducing BSCB permeability to Evans blue albumin and (131)I. These beneficial effects are most pronounced with AP713 (SCI-2) treatment. Interestingly, when these compounds were administered in identical conditions after tagging with nanowires, their beneficial effects on functional recovery and spinal cord pathology were further enhanced. However, topical administration of nanowires alone did not influence trauma-induced spinal cord pathology or motor functions. Taken together, our results, probably for the first time, indicate that drug delivery and therapeutic efficacy are enhanced when the compounds are administered with nanowires.

Burgeoning applications of nanotechnology are altering practices in traditional medicine. Promoted by the National Institutes of Health, nanomedicinal research is advancing technologies and revolutionizing strategies in clinical science by providing easy access to innovative nanodevices and nanosystems based on the rational design and precise integration of functional nanomaterials. Many long-standing challenges in clinical science could be met through advancement and revolutionization. Nanomedicinal diagnostics could acquire critical information regarding the status of diseased tissues and organs quickly and inexpensively with minimal sampling size and invasion. New strategies in therapeutic and regenerative nanomedicines will enable clinicians to take actions in a timely fashion and patient-friendly manner.