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1.
Life Sci ; 234: 116739, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31400352

RESUMO

AIM: This study aimed to investigate the effect of icariin (referred as ICA) on Alzheimer's disease (AD) model through endoplasmic reticulum (ER) stress pathway. MAIN METHODS: Nine months male APP/PS1 and wild-type (WT) mice were randomly divided into four groups: APP/PS1 control, APP/PS1 + ICA, WT control and WT + ICA groups. The treated mice were given ICA 60 mg/kg/d and control mice were received the same volume distilled water for consecutive 3 months. The Morris water maze and Novel object recognition were used to detect animals' behavior. Nissl staining was used to observe the neuronal morphology in hippocampus area. Aß deposition in hippocampal region was observed by immunofluorescence staining. TUNEL staining was used to observe apoptosis. Detection of expression of ER stress related factors by Western blot and real time RT-PCR. KEY FINDINGS: Chronically administrated with ICA compared with APP/PS1 control mice significantly improved the behavior performance, reduced neuronal apoptosis, as well as suppressing the ER stress signaling pathway, including that decreased the level of glucose-regulated protein 78, phosphorylated ER-regulated kinase and phosphorylated eukaryotic initiation factor α, as well activating transcription factor-4, C/EBP homologous protein, DNA damage inducible protein 34 and tribbles homologous protein 3. SIGNIFICANCE: Our data indicated that ICA suppressed the ER stress signaling to protect against AD animal model, these findings suggest that a potential point for researching the effect of ICA on neurodegeneration.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Precursor de Proteína beta-Amiloide/metabolismo , Cognição/efeitos dos fármacos , Medicamentos de Ervas Chinesas/uso terapêutico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Flavonoides/uso terapêutico , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Medicamentos de Ervas Chinesas/farmacologia , Flavonoides/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Masculino , Memória/efeitos dos fármacos , Camundongos
2.
Life Sci ; 234: 116775, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31425697

RESUMO

AIMS: The activation of the angiotensin (Ang) II after acute kidney injury (AKI) triggers oxidative stress and inflammatory cascade which involved not only the kidneys but also the brain. Ang II through the Ang II type 1 receptor (AT1R) may have deleterious effects on hippocampal synaptic transmission and cognitive functions under uremic encephalopathy. The present study was conducted to examine the effects of AT1R antagonist on AKI-induced cognitive and synaptic plasticity impairment. MAIN METHODS: Here, we investigated the effect of AKI and possible pathophysiological roles of AT1R with the selective AT1R antagonist losartan (10 mg/kg/day for consecutive 9 days) on cognitive performance using passive avoidance and Morris water maze tests. In order to understand the synaptic transmission, in vivo short and long-term plasticity were evaluated at the Schaffer collateral-CA1 synapse. Biochemical analysis was also performed to detect possible hippocampal nitric oxide and oxidative stress mechanisms. KEY FINDINGS: Our data provide evidence of hippocampal complication following AKI with increased level of nitrite (P < 0.01 vs. sham) as well as oxidative stress (P < 0.01 vs. sham) that may be responsible for behavioral dysfunction under uremia (spatial memory, P < 0.001; passive avoidance P < 0.01 vs. sham). Losartan treatment effectively protects against cognitive (spatial memory, P < 0.01; passive avoidance P < 0.05 vs. AKI-veh) and synaptic plasticity impairments induced by AKI possibly via modulation of oxidative stress in the hippocampus (P < 0.01 vs. AKI-veh). SIGNIFICANCE: The present study conclusively demonstrated a protective role of AT1R antagonist losartan in hippocampal complication and neurocognitive dysfunction after AKI via modulating oxidative stress.


Assuntos
Lesão Renal Aguda/complicações , Bloqueadores do Receptor Tipo 1 de Angiotensina II/uso terapêutico , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Hipocampo/efeitos dos fármacos , Losartan/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Lesão Renal Aguda/metabolismo , Lesão Renal Aguda/fisiopatologia , Animais , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/fisiopatologia , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Masculino , Memória/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Ratos Wistar , Receptor Tipo 1 de Angiotensina/metabolismo
3.
Chem Biol Interact ; 312: 108775, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31369746

RESUMO

Postnatal exposure to valproic acid (VPA) in rodents induces autism-like neurobehavioral defects which are comparable to the motor and cognitive deficits observed in humans with autism spectrum disorder (ASD). Histamine H3 receptor (H3R) and acetylcholine esterase (AChE) are involved in several cognitive disorders such as Alzheimer's disease, schizophrenia, anxiety, and narcolepsy, all of which are comorbid with ASD. Therefore, the present study aimed at evaluating effect of the novel dual-active ligand E100 with high H3R antagonist affinity and balanced AChE inhibition on autistic-like repetitive behavior, anxiety parameters, locomotor activity, and neuroinflammation in a mouse model of VPA-induced ASD in C57BL/6 mice. E100 (5, 10, and 15 mg/kg) dose-dependently and significantly ameliorated repetitive and compulsive behaviors by reducing the increased percentages of nestlets shredded (all P < 0.05). Moreover, pretreatment with E100 (10 and 15 mg/kg) attenuated disturbed anxiety levels (P < 0.05) but failed to restore the hyperactivity observed in the open field test. Furthermore, pretreatment with E100 (10 mg/kg) the increased microglial activation, proinflammatory cytokines and expression of NF-κB, iNOS, and COX-2 in the cerebellum as well as the hippocampus (all P < 0.05). These results demonstrate the ameliorative effects of E100 on repetitive compulsive behaviors in a mouse model of ASD. To our knowledge, this is the first in vivo demonstration of the effectiveness of a potent dual-active H3R antagonist and AChE inhibitor against autistic-like repetitive compulsive behaviors and neuroinflammation, and provides evidence for the role of such compounds in treating ASD.


Assuntos
Transtorno do Espectro Autista/patologia , Comportamento Animal/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Antagonistas dos Receptores Histamínicos H3/farmacologia , Animais , Transtorno do Espectro Autista/induzido quimicamente , Transtorno do Espectro Autista/tratamento farmacológico , Inibidores da Colinesterase/uso terapêutico , Citocinas/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Hipocampo/metabolismo , Antagonistas dos Receptores Histamínicos H3/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Transcrição RelA/metabolismo , Ácido Valproico/toxicidade
4.
Toxicol Lett ; 314: 106-116, 2019 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-31306743

RESUMO

Chronic low-level lead exposure alters cognitive function in young children however the mechanisms mediating these deficits in the brain are not known. Previous studies in our laboratory showed that early lead exposure reduced the number of microglial cells in hippocampus/dentate gyrus of C57BL/6 J mice. In the current study, C-C chemokine receptor 7 (CCR7) and major histocompatibility complex II (MHC II) were examined to investigate whether these neuroimmune factors which are known to trigger cell migration and antigen presentation, were altered by early chronic lead exposure. Thirty-six C57BL/6 J male mice were exposed to 0 ppm (controls, n = 12), 30 ppm (low-dose, n = 12), or 430 ppm (higher-dose, n = 12) of lead acetate via dams' milk from postnatal day (PND) 0 to 28. Flow cytometry was used to quantify cell types and cell surface expression of MHC II and CCR7 in hippocampal and whole brain microglia. Non-parametric independent samples median tests were used to test for statistically significant differences between groups. As compared to controls, CCR7 in hippocampal microglia was decreased in the low-dose group, measured as geometric mean fluorescence intensity (GMFI); in the higher-dose group CCR7+MHC II- hippocampal microglia were decreased. Further analyses revealed that the higher-dose group had decreased percentage of CCR7+MHC II- hippocampal macrophages as compared to controls but increased MHC II levels in CCR7+MHC II+ hippocampal macrophages as compared to controls. It was also noted that lead exposure disrupted the balance of MHC II and/or CCR7 in lead exposed animals. Reduced CCR7 in hippocampal microglia might alter the neuroimmune environment in hippocampi of lead exposed animals. Additional studies are needed to test this possibility.


Assuntos
Hipocampo/efeitos dos fármacos , Intoxicação do Sistema Nervoso por Chumbo na Infância/etiologia , Microglia/efeitos dos fármacos , Compostos Organometálicos/toxicidade , Receptores CCR7/metabolismo , Animais , Animais Recém-Nascidos , Regulação para Baixo , Feminino , Hipocampo/metabolismo , Hipocampo/patologia , Antígenos de Histocompatibilidade Classe II/metabolismo , Lactação , Intoxicação do Sistema Nervoso por Chumbo na Infância/metabolismo , Intoxicação do Sistema Nervoso por Chumbo na Infância/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Fatores de Tempo
5.
J Agric Food Chem ; 67(32): 9039-9049, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31353898

RESUMO

This study focused on the effects of oxidized tyrosine products (OTPs) and major component dityrosine (DT) on the brain and behavior of growing mice. Male and female mice were treated with daily intragastric administration of either tyrosine (Tyr; 420 µg/kg body weight), DT (420 µg/kg body weight), or OTPs (1909 µg/kg body weight) for 35 days. We found that pure DT and OTPs caused redox state imbalance, elevated levels of inflammatory factors, hippocampal oxidative damage, and neurotransmitter disorders while activating the mitochondrial apoptosis pathway in the hippocampus and downregulating the genes associated with learning and memory. These events eventually led to growing mice learning and memory impairment, lagging responses, and anxiety-like behaviors. Furthermore, the male mice exhibited slightly more oxidative damage than the females. These findings imply that contemporary diets and food-processing strategies of the modern world should be modified to reduce oxidized protein intake.


Assuntos
Transtornos da Memória/etiologia , Aprendizagem Espacial , Tirosina/análogos & derivados , Tirosina/efeitos adversos , Tirosina/química , Animais , Comportamento Animal , Feminino , Hipocampo/crescimento & desenvolvimento , Hipocampo/metabolismo , Humanos , Masculino , Transtornos da Memória/metabolismo , Transtornos da Memória/fisiopatologia , Transtornos da Memória/psicologia , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , Estresse Oxidativo , Tirosina/metabolismo
6.
Chem Pharm Bull (Tokyo) ; 67(7): 699-706, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31257325

RESUMO

In our search for novel orally active α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor antagonists, we found that conversion of an allyl group in the lead compound 2-[allyl(4-methylphenyl)amino]-4H-pyrido[3,2-e][1,3]thiazin-4-one (4) to a 2-cyanoethyl group significantly increased inhibitory activity against AMPA receptor-mediated kainate-induced toxicity in rat hippocampal cultures. Here, we synthesized 10 analogs bearing a 2-cyanoethyl group and administered them to mice to evaluate their anticonvulsant activity in maximal electroshock (MES)- and pentylenetetrazol (PTZ)-induced seizure tests, and their effects on motor coordination in a rotarod test. 3-{(4-Oxo-4H-pyrido[3,2-e][1,3]thiazin-2-yl)[4-(trifluoromethoxy)phenyl]amino}propanenitrile (25) and 3-[(2,2-difluoro-2H-1,3-benzodioxol-5-yl)(4-oxo-4H-pyrido[3,2-e][1,3]thiazin-2-yl)amino]propanenitrile (27) exhibited potent anticonvulsant activity in both seizure tests and induced minor motor disturbances as indicated in the rotarod test. The protective index values of 25 and 27 for MES-induced seizures (10.7 and 12.0, respectively) and PTZ-induced seizures (6.0 and 5.6, respectively) were considerably higher compared with those of YM928 (5) and talampanel (1).


Assuntos
Anticonvulsivantes/síntese química , Nitrilos/química , Receptores de AMPA/antagonistas & inibidores , Administração Oral , Animais , Anticonvulsivantes/farmacologia , Anticonvulsivantes/uso terapêutico , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Locomoção/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos ICR , Microssomos Hepáticos/metabolismo , Nitrilos/farmacologia , Nitrilos/uso terapêutico , Pentilenotetrazol/toxicidade , Ratos , Ratos Wistar , Receptores de AMPA/metabolismo , Convulsões/induzido quimicamente , Convulsões/tratamento farmacológico , Convulsões/veterinária , Relação Estrutura-Atividade
7.
Life Sci ; 232: 116611, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31260683

RESUMO

PURPOSE: To observe the effect of dexmedetomidine (DEX) on mitochondrial apoptosis of hippocampal neurons in hypoxia/reoxygenation (H/R) brain injury in developing rats, and to investigate its regulatory mechanism on HIF-1α/p53 signaling pathway. METHODS: Hypoxia/reoxygenation model was used in this study. TUNEL assay was performed to detect cell apoptosis. Immunohistochemical analysis and Western-blotting analysis were conducted to detect Cytochrome-C (Cyt-c), APAF-1, Caspase-3, Neuroglobin (Ngb), HIF-1α and p53 expression. After 28 days, Morris water maze (MWM) was performed. RESULTS: 50 µg/kg DEX improved H/R-induced brain injury and inhibited mitochondrial apoptosis in rats. Western-blotting and Immunohistochemical results demonstrated that DEX could up-regulate Ngb through α2 receptor to inhibit H/R-induced mitochondrial apoptosis. In addition, by adding inhibitors yohimbine and 2-methoxyestradiol (2ME2), we found that DEX could activate HIF-1α/p53 signaling pathway. MWM test showed that DEX could enhance long-term learning and memory of H/R brain injury rats. CONCLUSION: DEX alleviates H/R-induced brain injury and mitochondrial apoptosis in developing rats through α2 receptor, which may be related to activation of HIF-1α/p53 signaling pathway to up-regulate the expression of Ngb.


Assuntos
Hipóxia Celular/efeitos dos fármacos , Dexmedetomidina/farmacologia , Hipocampo/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Neurônios/efeitos dos fármacos , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Hipocampo/metabolismo , Hipocampo/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Masculino , Mitocôndrias/metabolismo , Neurônios/metabolismo , Neurônios/patologia , Substâncias Protetoras/farmacologia , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/metabolismo , Transdução de Sinais/efeitos dos fármacos , Proteína Supressora de Tumor p53/efeitos dos fármacos
8.
Life Sci ; 232: 116667, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31326567

RESUMO

AIMS: Gamma amino butyric acid (GABA) imbalance plays a critical role in most neurological disorders including epilepsy. This study assessed the involvement of mild exercise on GABA imbalance following by seizure induction in rats. MAIN METHODS: Seizure was induced by pentylentetrazole (PTZ) injection. Animals were divided into sham, seizure, exercise (EX), co-seizure-induced exercise (Co-SI EX) and Pre-SI EX groups. In the Co-SI EX group, doing exercise and seizure induction was carried out during four weeks. Animals in the Pre-SI EX group exercised in week 1 to week 8 and seizures were induced in week 5 to week 8. Seizure properties, neural viability and expressions of glutamic acid decarboxylase 65 (GAD65) and GABAA receptor α1 in the hippocampus were assessed. KEY FINDINGS: Seizure severity reduced and latency increased in the Co-SI EX and Pre-SI EX groups compared to seizure group. The mean number of dark neurons decreased in all exercise groups compared to seizure group in both CA1 and CA3 areas. The gene level of GAD65 and GABAA receptor α1 was highly expressed in the Co-SI EX group in the hippocampal area. Distribution of GAD65 in the both CA1 and CA3 areas increased in the EX and Co-SI EX groups. GABAA receptor α1 was up-regulated in the CA3 area of Co-SI EX group and down-regulated in the CA1 and CA3 areas of Pre-SI EX group. SIGNIFICANCE: These findings suggest that exercise develop anti-epileptic as well as neuroprotective effects by modulating of GABA disinhibition.


Assuntos
Condicionamento Físico Animal , Convulsões/induzido quimicamente , Transdução de Sinais , Ácido gama-Aminobutírico/metabolismo , Animais , Modelos Animais de Doenças , Expressão Gênica , Glutamato Descarboxilase/genética , Glutamato Descarboxilase/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/enzimologia , Hipocampo/metabolismo , Masculino , Pentilenotetrazol/administração & dosagem , Pentilenotetrazol/toxicidade , Ratos , Ratos Wistar , Receptores de GABA-A/genética , Receptores de GABA-A/metabolismo , Convulsões/metabolismo
9.
Nat Commun ; 10(1): 2489, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-31171815

RESUMO

Down syndrome (DS), trisomy of human chromosome 21 (Hsa21), results in a broad range of phenotypes. A recent study reported that DS cells show genome-wide transcriptional changes in which up- or down-regulated genes are clustered in gene expression dysregulation domains (GEDDs). GEDDs were also reported in fibroblasts derived from a DS mouse model duplicated for some Hsa21-orthologous genes, indicating cross-species conservation of this phenomenon. Here we investigate GEDDs using the Dp1Tyb mouse model of DS, which is duplicated for the entire Hsa21-orthologous region of mouse chromosome 16. Our statistical analysis shows that GEDDs are present both in DS cells and in Dp1Tyb mouse fibroblasts and hippocampus. However, we find that GEDDs do not depend on the DS genotype but occur whenever gene expression changes. We conclude that GEDDs are not a specific feature of DS but instead result from the clustering of co-regulated genes, a function of mammalian genome organisation.


Assuntos
Síndrome de Down/genética , Fibroblastos/metabolismo , Expressão Gênica/genética , Hipocampo/metabolismo , Animais , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Genoma , Genótipo , Camundongos , Família Multigênica , Fenótipo
10.
Nat Commun ; 10(1): 2819, 2019 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-31249307

RESUMO

Hippocampal hyperactivity is correlated with psychosis in schizophrenia patients and likely attributable to deficits in GABAergic signaling. Here we attempt to reverse this deficit by overexpression of the α5-GABAA receptor within the ventral hippocampus (vHipp). Indeed, this is sufficient to normalize vHipp activity and downstream alterations in dopamine neuron function in the MAM rodent model. This approach also attenuated behavioral deficits in cognitive flexibility. To understand the specific pathways that mediate these effects, we used chemogenetics to manipulate discrete projections from the vHipp to the nucleus accumbens (NAc) or prefrontal cortex (mPFC). We found that inhibition of the vHipp-NAc, but not the vHipp-mPFC pathway, normalized aberrant dopamine neuron activity. Conversely, inhibition of the vHipp-mPFC improved cognitive function. Taken together, these results demonstrate that restoring GABAergic signaling in the vHipp improves schizophrenia-like deficits and that distinct behavioral alterations are mediated by discrete projections from the vHipp to the NAc and mPFC.


Assuntos
Hipocampo/metabolismo , Receptores de GABA-A/metabolismo , Sinapses/metabolismo , Animais , Comportamento Animal , Cognição , Neurônios Dopaminérgicos/metabolismo , Feminino , Masculino , Vias Neurais , Núcleo Accumbens/metabolismo , Córtex Pré-Frontal/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/genética , Sinapses/genética
11.
Gen Physiol Biophys ; 38(4): 365-368, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31219430

RESUMO

The role of vascular endothelial growth factor (VEGF) in chronic stress and neurodevelopmental disorders is of growing research interest. Here we show that post-weaning isolation rearing of rats decreased gene expression of VEGF in the hippocampus. Gene expression of VEGF upstream regulator fibroblast growth factor-2 (FGF-2) or its downstream mediator endothelial nitric oxide synthase (eNOS) was unchanged. Other signaling pathways appear to be involved in isolation-induced reduction in VEGF gene expression. Sex differences in VEGF and eNOS gene expression with significantly higher mRNA levels in females than males were revealed.


Assuntos
Regulação para Baixo , Hipocampo/metabolismo , Isolamento Social , Fator A de Crescimento do Endotélio Vascular/genética , Desmame , Animais , Feminino , Fator 2 de Crescimento de Fibroblastos/genética , Masculino , Óxido Nítrico Sintase Tipo III/genética , RNA Mensageiro/análise , RNA Mensageiro/genética , Ratos
12.
Biomed Environ Sci ; 32(5): 345-356, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31217051

RESUMO

OBJECTIVE: To investigate the molecular mechanisms of the adverse effects of exposure to sulfamonomethoxin (SMM) in pregnancy on the neurobehavioral development of male offspring. METHODS: Pregnant mice were randomly divided into four groups: control- (normal saline), low- [10 mg/(kg•day)], middle- [50 mg/(kg•day)], and high-dose [200 mg/(kg•day)] groups, which received SMM by gavage daily during gestational days 1-18. We measured the levels of short-chain fatty acids (SCFAs) in feces from dams and male pups. Furthermore, we analyzed the mRNA and protein levels of genes involved in the mammalian target of rapamycin (mTOR) pathway in the hippocampus of male pups by RT-PCR or Western blotting. RESULTS: Fecal SCFA concentrations were significantly decreased in dams. Moreover, the production of individual fecal SCFAs was unbalanced, with a tendency for an increased level of total fecal SCFAs in male pups on postnatal day (PND) 22 and 56. Furthermore, the phosphatidylinositol 3-kinase (PI3k)/protein kinase B (AKT)/mTOR or mTOR/ribosomal protein S6 kinase 1 (S6K1)/4EBP1 signaling pathway was continuously upregulated until PND 56 in male offspring. In addition, the expression of Sepiapterin Reductase (SPR), a potential target of mTOR, was inhibited. CONCLUSION: In utero exposure to SMM, persistent upregulation of the hippocampal mTOR pathway related to dysfunction of the gut (SCFA)-brain axis may contribute to cognitive deficits in male offspring.


Assuntos
Anti-Infecciosos/toxicidade , Hipocampo/efeitos dos fármacos , Memória/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Sulfamonometoxina/toxicidade , Oxirredutases do Álcool/metabolismo , Animais , Ácidos Graxos Voláteis/análise , Fezes/química , Feminino , Hipocampo/metabolismo , Masculino , Camundongos Endogâmicos ICR , Gravidez , Serina-Treonina Quinases TOR/metabolismo
13.
Life Sci ; 230: 169-177, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150685

RESUMO

AIMS: Hippocampal oxidative stress and apoptosis of CA1 neurons play significant roles in the pathophysiology of diabetes-associated cognitive decline (DACD). The present study was aimed to elucidate the putative effects of sesamin, a major lignan of sesame seed, against DACD, and possible involvement of anti-oxidative and anti-apoptotic mechanisms. MAIN METHODS: Fifty adult male Wistar rats were randomly divided into control, control-sesamin (30 mg/kg/day), diabetic, diabetic-sesamin (30 mg/kg/day), and diabetic-insulin (6 IU/rat/day) groups. Diabetic rats were treated with sesamin (P.O.) or insulin (S.C.) for eight consecutive weeks. Cognitive performance was evaluated in a Morris Water Maze (MWM) test; in addition, superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), and malondialdehyde (MDA) concentrations were assayed in the hippocampus using assay kits. Moreover, hematoxylin-eosin (HE), TUNEL, and immunohistochemistry (IHC) stainings were conducted to evaluate histological changes, the apoptosis status and expression of pro- and anti-apoptotic proteins in the hippocampal CA1 neurons, respectively. KEY FINDINGS: The results showed that diabetes reduced the spatial cognitive ability in MWM, which was accompanied by decrease in SOD, CAT, and GPx activities and increase in MDA level in the hippocampus. Additionally, diabetes resulted in neuronal loss, enhanced apoptotic index, elevated the expression of pro-apoptotic Bax protein, and decreased the expression of anti-apoptotic Bcl-2 protein in the hippocampal CA1 neurons. Interestingly, sesamin treatment improved all the above-mentioned deficits of diabetes at a comparable level with insulin therapy. SIGNIFICANCE: The results suggest that sesamin could be a promising potential therapeutic agent against DACD, possibly through its intertwined anti-hyperglycemic, anti-oxidative, and anti-apoptotic properties.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Complicações do Diabetes/tratamento farmacológico , Dioxóis/farmacologia , Lignanas/farmacologia , Animais , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Diabetes Mellitus Experimental/metabolismo , Dioxóis/metabolismo , Glutationa Peroxidase/metabolismo , Hipocampo/metabolismo , Insulina/farmacologia , Lignanas/metabolismo , Masculino , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Ratos , Ratos Wistar , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo
14.
Nat Commun ; 10(1): 2394, 2019 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-31160584

RESUMO

To understand the molecular processes that link Aß amyloidosis, tauopathy and neurodegeneration, we screened for tau-interacting proteins by immunoprecipitation/LC-MS. We identified the carboxy-terminal PDZ ligand of nNOS (CAPON) as a novel tau-binding protein. CAPON is an adaptor protein of neuronal nitric oxide synthase (nNOS), and activated by the N-methyl-D-aspartate receptor. We observed accumulation of CAPON in the hippocampal pyramidal cell layer in the AppNL-G-F -knock-in (KI) brain. To investigate the effect of CAPON accumulation on Alzheimer's disease (AD) pathogenesis, CAPON was overexpressed in the brain of AppNL-G-F mice crossbred with MAPT (human tau)-KI mice. This produced significant hippocampal atrophy and caspase3-dependent neuronal cell death in the CAPON-expressing hippocampus, suggesting that CAPON accumulation increases neurodegeneration. CAPON expression also induced significantly higher levels of phosphorylated, oligomerized and insoluble tau. In contrast, CAPON deficiency ameliorated the AD-related pathological phenotypes in tauopathy model. These findings suggest that CAPON could be a druggable AD target.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Doença de Alzheimer/metabolismo , Hipocampo/metabolismo , Agregação Patológica de Proteínas/metabolismo , Células Piramidais/metabolismo , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Atrofia , Caspase 3/metabolismo , Morte Celular , Cromatografia Líquida , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Hipocampo/patologia , Humanos , Imunoprecipitação , Espectrometria de Massas , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Agregação Patológica de Proteínas/patologia , Células Piramidais/patologia , Tauopatias , Proteínas tau/metabolismo
15.
J Agric Food Chem ; 67(27): 7684-7693, 2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31203623

RESUMO

This study investigated the alleviative effect of caffeic acid (CA) on Alzheimer's disease (AD) pathogenesis and associated mechanisms in high-fat (HF) diet-induced hyperinsulinemic rats. The results of a Morris water maze indicated that, by administrating CA (30 mg/kg b.w./day) for 30 weeks, the memory and learning impairments in HF-induced hyperinsulinemic rats were significantly ameliorated. CA also enhanced superoxide dismutase and glutathione free radical scavenger activity in hyperinsulinemic rats. The Western blot data further confirmed that protein expressions of phosphorylated-glycogen synthase kinase 3ß (GSK3ß) were significantly increased, whereas the expression of phosphorylated-tau protein decreased in the hippocampus of rats administered with CA in comparison with the HF group. Moreover, the expression of amyloid precursor protein (APP) and ß-site APP cleaving enzyme were attenuated, subsequently lowering the level of ß-amyloid 1-42 (Aß 1-42) in the hippocampus of CA-treated hyperinsulinemic rats. CA also significantly increased the expression of synaptic proteins in HF rats.


Assuntos
Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Ácidos Cafeicos/administração & dosagem , Insulina/metabolismo , Plasticidade Neuronal/efeitos dos fármacos , Doença de Alzheimer/metabolismo , Animais , Antioxidantes/química , Córtex Cerebral/química , Córtex Cerebral/enzimologia , Córtex Cerebral/metabolismo , Dieta Hiperlipídica , Modelos Animais de Doenças , Glutationa/metabolismo , Glicogênio Sintase Quinase 3 beta/análise , Glicogênio Sintase Quinase 3 beta/metabolismo , Hipocampo/química , Hipocampo/enzimologia , Hipocampo/metabolismo , Hiperinsulinismo/etiologia , Hiperinsulinismo/metabolismo , Masculino , Fosforilação , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Proteínas tau/análise , Proteínas tau/metabolismo
16.
Life Sci ; 231: 116532, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31170417

RESUMO

AIMS: It is a promising approach to search the therapeutic strategies for treating lead (Pb) toxicity. Allicin, a natural compound extracted from Allium sativum (garlic), has been reported to have many beneficially biological properties. In this study, we investigated the protective effects of allicin on learning and memory function of rats exposed by lead acetate at developmental stage. MATERIALS AND METHODS: Rats received lead acetate for inducing toxicity, and gavaged with allicin to ameliorate this toxicity. Morris water maze test was performed to determine learning and memory function. Superoxide dismutase (SOD), glutathione (GSH) and methane dicarboxylic aldehyde (MDA) was measured to determine oxidative stress. Immunofluorescence was carried out to analyze GFAP-positive cells. The protein expression of ERK, p-ERK, EGFR and p-EGFR were detected using western blot. KEY FINDINGS: We found that allicin ameliorated lead acetate-caused learning and memory deficits by promoting hippocampus astrocyte differentiation, which mainly through EGFR/ERK signaling. Moreover, allicin attenuated the increased ROS level by regulating the oxidative defense system. SIGNIFICANCE: These results suggest that allicin is a potent agent able to ameliorate lead acetate-induced learning and memory deficits during early development, and may thus be useful for defeating lead acetate toxicity.


Assuntos
Transtornos de Aprendizagem/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Ácidos Sulfínicos/farmacologia , Animais , Antioxidantes/farmacologia , Feminino , Glutationa/metabolismo , Hipocampo/metabolismo , Chumbo/efeitos adversos , Intoxicação por Chumbo/tratamento farmacológico , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Memória/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Compostos Organometálicos/efeitos adversos , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ratos , Ratos Wistar , Ácidos Sulfínicos/metabolismo , Superóxido Dismutase/metabolismo
17.
Life Sci ; 231: 116566, 2019 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31201846

RESUMO

AIMS: Diabetes mellitus can cause cognitive impairments, a state between normal aging and dementia. Effective clinical interventions are urgently needed to prevent or treat this complication. Liraglutide as a glucagon-like peptide 1 analog has been shown to exert memory-enhancing and neuroprotective effects on neurodegenerative diseases. This study aims to investigate the neuroprotective effects of liraglutide in streptozotocin (STZ)-induced diabetic mice with cognitive deficits. METHODS: Male C57BL/6J mice were intraperitoneal injected with STZ (65 mg/kg body weight daily for 5 days) to induce type 1 diabetes model. Then the mice were treated with liraglutide (250 mg/kg/day, for 6 weeks) or saline. Weekly changes of body weight and fasting blood glucose were measured. Cognitive performance was evaluated by Morris water maze test. The ultrastructure of hippocampus was observed by transmission electron microscope. The superoxide dismutase activities and malondialdehyde levels in the hippocampus were detected by biochemistry assay. Apoptosis-related proteins and phosphoinositide 3-kinase (PI3K)/protein kinase-B (Akt) signaling were detected by Western blotting. KEY FINDINGS: We found that STZ-induced diabetic mice exhibited impaired learning and memory, ultrastructure damage of hippocampal neurons and synapses, exacerbated oxidative stress and neuronal apoptosis, as compared to the control mice. These effects were attenuated by the treatment with liraglutide. Furthermore, liraglutide reversed diabetes-induced alterations in PI3K/Akt signaling pathway that plays an essential role in modulating neuronal survival, apoptosis and plasticity. SIGNIFICANCE: These data suggest that the neuroprotective effects of liraglutide on diabetes-induced cognitive impairments are associated with the improvements of hippocampal synapses and inhibition of neuronal apoptosis.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Complicações do Diabetes/tratamento farmacológico , Liraglutida/farmacologia , Animais , Apoptose/efeitos dos fármacos , Glicemia/efeitos dos fármacos , Cognição/efeitos dos fármacos , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/metabolismo , Modelos Animais de Doenças , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipoglicemiantes/farmacologia , Liraglutida/metabolismo , Masculino , Memória/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Neurônios/efeitos dos fármacos , Neurônios/fisiologia , Neuroproteção/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , Estreptozocina/efeitos adversos , Sinapses/efeitos dos fármacos , Sinapses/fisiologia
18.
Cell Mol Life Sci ; 76(16): 3141-3156, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31168660

RESUMO

Neurotrauma, a term referencing both traumatic brain and spinal cord injuries, is unique to neurodegeneration in that onset is clearly defined. From the perspective of matrix metalloproteinases (MMPs), there is opportunity to define their temporal participation in injury and recovery beginning at the level of the synapse. Here we examine the diverse roles of MMPs in the context of targeted insults (optic nerve lesion and hippocampal and olfactory bulb deafferentation), and clinically relevant focal models of traumatic brain and spinal cord injuries. Time-specific MMP postinjury signaling is critical to synaptic recovery after focal axonal injuries; members of the MMP family exhibit a signature temporal profile corresponding to axonal degeneration and regrowth, where they direct postinjury reorganization and synaptic stabilization. In both traumatic brain and spinal cord injuries, MMPs mediate early secondary pathogenesis including disruption of the blood-brain barrier, creating an environment that may be hostile to recovery. They are also critical players in wound healing including angiogenesis and the formation of an inhibitory glial scar. Experimental strategies to reduce their activity in the acute phase result in long-term neurological recovery after neurotrauma and have led to the first clinical trial in spinal cord injured pet dogs.


Assuntos
Metaloproteinases da Matriz/metabolismo , Traumatismos da Medula Espinal/patologia , Animais , Axônios/metabolismo , Barreira Hematoencefálica/metabolismo , Hipocampo/metabolismo , Humanos , Bulbo Olfatório/metabolismo , Nervo Óptico/metabolismo , Traumatismos da Medula Espinal/metabolismo , Sinapses/fisiologia
19.
Chem Biol Interact ; 308: 279-287, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31150628

RESUMO

The dose-dependent neuroprotective role of licorice-derived glycyrrhizin during subacute neuroterminal norepinephrine (NE) depletion was studied in rat brain. Experimental design included thirty 5-week-old male rats randomly divided into five groups. Compared to the saline-injected control group, the group receiving daily intraperitoneal injection of fusaric acid (FA; 5 mg/kg/b.w.) for 30 days showed pharmacological depletion of NE. The neuroprotective effects of three successively increasing oral doses of glycyrrhizin were examined in FA-treated rats. Neurochemical parameters and histo-/immunohistopathological changes in the hippocampus were examined. FA generated global hippocampal stress with altered neurobiochemical parameters, accompanied by immune-confirmed inflammatory tissue damage, and noticeable behavioral changes. Although glycyrrhizin after FA-induced intoxication did not correct the recorded drop in the NE level, it decreased the dopamine levels to control levels. Similarly, glycyrrhizin at a high dose restored the serotonin level to its normal value and blocked the FA-induced increase in the level of its metabolite, 5-hydroxyindoleacetic acid. The FA-induced rise in γ-aminobutyric acid (GABA) and histamine was alleviated after administration of a high dose of glycyrrhizin. This was accompanied by improvements in the bioenergetic status and neuronal regenerative capacity through recovery of ATP and brain-derived neurotrophic factor levels to the pre-intoxicated values. High doses of glycyrrhizin also ameliorated the FA-generated behavioral changes and oxidative damage, manifested by the reduction in the expression of cortical pro-apoptotic caspase 3 in the same group. This study suggests that glycyrrhizin can potentially mend most of the previously evoked neuronal damage induced by FA intoxication in the brain of an experimental rat model.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Ácido Glicirrízico/farmacologia , Hipocampo/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Norepinefrina/metabolismo , Acetilcolinesterase/metabolismo , Animais , Comportamento Animal/efeitos dos fármacos , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/patologia , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Ácido Fusárico/toxicidade , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Síndromes Neurotóxicas/tratamento farmacológico , Síndromes Neurotóxicas/patologia , Síndromes Neurotóxicas/veterinária , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Regulação para Cima/efeitos dos fármacos , Ácido gama-Aminobutírico/metabolismo
20.
Int J Mol Sci ; 20(9)2019 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-31067671

RESUMO

Effects of fructose 1,6-bisphosphate (F-1,6-P2) towards N-methyl-d-aspartate NMDA excitotoxicity were evaluated in rat organotypic hippocampal brain slice cultures (OHSC) challenged for 3 h with 30 µM NMDA, followed by incubations (24, 48, and 72 h) without (controls) and with F-1,6-P2 (0.5, 1 or 1.5 mM). At each time, cell necrosis was determined by measuring LDH in the medium. Energy metabolism was evaluated by measuring ATP, GTP, ADP, AMP, and ATP catabolites (nucleosides and oxypurines) in deproteinized OHSC extracts. Gene expressions of phosphofructokinase, aldolase, and glyceraldehyde-3-phosphate dehydrogenase were also measured. F-1,6-P2 dose-dependently decreased NMDA excitotoxicity, abolishing cell necrosis at the highest concentration tested (1.5 mM). Additionally, F-1,6-P2 attenuated cell energy imbalance caused by NMDA, ameliorating the mitochondrial phosphorylating capacity (increase in ATP/ADP ratio) Metabolism normalization occurred when using 1.5 mM F-1,6-P2. Remarkable increase in expressions of phosphofructokinase, aldolase and glyceraldehyde-3-phosphate dehydrogenase (up to 25 times over the values of controls) was also observed. Since this phenomenon was recorded even in OHSC treated with F-1,6-P2 with no prior challenge with NMDA, it is highly conceivable that F-1,6-P2 can enter into intact cerebral cells producing significant benefits on energy metabolism. These effects are possibly mediated by changes occurring at the gene level, thus opening new perspectives for F-1,6-P2 application as a useful adjuvant to rescue mitochondrial metabolism of cerebral cells under stressing conditions.


Assuntos
Frutose-Bifosfatase/farmacologia , Hipocampo/efeitos dos fármacos , N-Metilaspartato/toxicidade , Fármacos Neuroprotetores/farmacologia , Animais , Metabolismo Energético , Frutose-Bifosfato Aldolase/metabolismo , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Hipocampo/metabolismo , Hipocampo/patologia , Necrose , Fosfofrutoquinases/metabolismo , Nucleosídeos de Purina/metabolismo , Ratos , Ratos Wistar
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