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1.
Adv Neurobiol ; 32: 353-384, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37480466

RESUMO

Military personnel during combat or peacekeeping operations are exposed to extreme climates of hot or cold environments for longer durations. Spinal cord injury is quite common in military personnel following central nervous system (CNS) trauma indicating a possibility of altered pathophysiological responses at different ambient temperatures. Our previous studies show that the pathophysiology of brain injury is exacerbated in animals acclimated to cold (5 °C) or hot (30 °C) environments. In these diverse ambient temperature zones, trauma exacerbated oxidative stress generation inducing greater blood-brain barrier (BBB) permeability and cell damage. Extracts of Ginkgo biloba EGb-761 and BN-52021 treatment reduces brain pathology following heat stress. This effect is further improved following TiO2 nanowired delivery in heat stress in animal models. Several studies indicate the role of EGb-761 in attenuating spinal cord induced neuronal damages and improved functional deficit. This is quite likely that these effects are further improved following nanowired delivery of EGb-761 and BN-52021 with cerebrolysin-a balanced composition of several neurotrophic factors and peptide fragments in spinal cord trauma. In this review, TiO2 nanowired delivery of EGb-761 and BN-52021 with nanowired cerebrolysin is examined in a rat model of spinal cord injury at cold environment. Our results show that spinal cord injury aggravates cord pathology in cold-acclimated rats and nanowired delivery of EGb-761 and BN-52021 with cerebrolysin significantly induced superior neuroprotection, not reported earlier.


Assuntos
Bilobalídeos , Ginkgo biloba , Fármacos Neuroprotetores , Traumatismos da Medula Espinal , Animais , Ratos , Temperatura Baixa , Sistemas de Liberação de Medicamentos , Nanofios , Fármacos Neuroprotetores/uso terapêutico , Extratos Vegetais/uso terapêutico , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/fisiopatologia , China
2.
Prog Brain Res ; 265: 249-315, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34560923

RESUMO

Military personnel often exposed to high summer heat are vulnerable to heat stroke (HS) resulting in abnormal brain function and mental anomalies. There are reasons to believe that leakage of the blood-brain barrier (BBB) due to hyperthermia and development of brain edema could result in brain pathology. Thus, exploration of suitable therapeutic strategies is needed to induce neuroprotection in HS. Extracts of Gingko Biloba (EGb-761) is traditionally used in a variety of mental disorders in Chinese traditional medicine since ages. In this chapter, effects of TiO2 nanowired EGb-761 and BN-52021 delivery to treat brain pathologies in HS is discussed based on our own investigations. We observed that TiO2 nanowired delivery of EGb-761 or TiO2 BN-52021 is able to attenuate more that 80% reduction in the brain pathology in HS as compared to conventional drug delivery. The functional outcome after HS is also significantly improved by nanowired delivery of EGb-761 and BN-52021. These observations are the first to suggest that nanowired delivery of EGb-761 and BN-52021 has superior therapeutic effects in HS not reported earlier. The clinical significance in relation to the military medicine is discussed.


Assuntos
Bilobalídeos , Golpe de Calor , Fármacos Neuroprotetores , China , Ginkgo biloba , Ginkgolídeos , Humanos , Lactonas , Fármacos Neuroprotetores/farmacologia , Extratos Vegetais
3.
Prog Brain Res ; 258: 1-77, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33223033

RESUMO

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 (1×106) and cerebrolysin (a balanced composition of several neurotrophic factors and active peptide fragments) (5mL/kg) significantly induced neuroprotection in SD with CHI. Interestingly, TiO2 nanowired delivery of α-MSH (100µg), MSCs, and cerebrolysin (2.5mL/kg) induced enhanced neuroprotection with higher levels of α-MSH and BDNF and decreased the TNF-α in SD with CHI. These observations are the first to show that TiO2 nanowired administration of α-MSH, MSCs and cerebrolysin induces superior neuroprotection following SD in CHI, not reported earlier. The clinical significance of our findings in light of the current literature is discussed.


Assuntos
Traumatismos Craniocerebrais , Células-Tronco Mesenquimais , Aminoácidos , Animais , Radioisótopos do Iodo , Neuroproteção , Ratos , Privação do Sono , Titânio , alfa-MSH
4.
Mol Neurobiol ; 52(2): 867-81, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26133300

RESUMO

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.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Edema Encefálico/prevenção & controle , Cobre/toxicidade , Nanopartículas/toxicidade , Fármacos Neuroprotetores/farmacologia , Ondansetron/farmacologia , Agonistas do Receptor 5-HT3 de Serotonina/farmacologia , Prata/toxicidade , Privação do Sono/fisiopatologia , Animais , Proteínas Sanguíneas/metabolismo , Encéfalo/irrigação sanguínea , Encéfalo/patologia , Encéfalo/fisiopatologia , Química Encefálica/efeitos dos fármacos , Edema Encefálico/etiologia , Edema Encefálico/fisiopatologia , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/fisiopatologia , Transtornos Cognitivos/prevenção & controle , Corantes/farmacocinética , Cobre/administração & dosagem , Avaliação Pré-Clínica de Medicamentos , Implantes de Medicamento , Azul Evans/farmacocinética , Fadiga/etiologia , Fadiga/fisiopatologia , Fadiga/prevenção & controle , Radioisótopos do Iodo/farmacocinética , Masculino , Nanofios , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/uso terapêutico , Ondansetron/administração & dosagem , Ondansetron/uso terapêutico , Ratos , Ratos Sprague-Dawley , Teste de Desempenho do Rota-Rod , Transtornos de Sensação/etiologia , Transtornos de Sensação/fisiopatologia , Transtornos de Sensação/prevenção & controle , Serotonina/análise , Agonistas do Receptor 5-HT3 de Serotonina/administração & dosagem , Agonistas do Receptor 5-HT3 de Serotonina/uso terapêutico , Prata/administração & dosagem , Privação do Sono/complicações , Fatores de Tempo
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