Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 74
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Molecules ; 28(9)2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37175152

RESUMO

Versican is a chondroitin sulfate proteoglycan (CSPG), which deposits in perineurium as a physical barrier and prevents the growth of axons out of the fascial boundary. Several studies have indicated that the chondroitin sulfate (CS) chains on versican have several possible functions beyond the physical barrier, including the ability to stabilize versican core protein in the extracellular matrix. As chondroitin sulfate synthase 1 (Chsy1) is a crucial enzyme for CS elongation, we hypothesized that in vivo knockdown of Chsy1 at peripheral nerve lesion site may decrease CS and versican accumulation, and result in accelerating neurite regeneration. In the present study, end-to-side neurorrhaphy (ESN) in Wistar rats was used as an in vivo model of peripheral nerve injury to evaluate nerve regeneration after surgical intervention. The distribution and expression of versican and Chsy1 in regenerating axons after ESN was studied using confocal microscopy and western blotting. Chsy1 was silenced at the nerve lesion (surgical) site using in vivo siRNA transfection. The results indicated that Chsy1 was successfully silenced in nerve tissue, and its downregulation was associated with functional recovery of compound muscle action potential. Silencing of Chsy1 also decreased the accumulation of versican core protein, suggesting that transient treating of Chsy1-siRNA may be an alternative and an effective strategy to promote injured peripheral nerve regeneration.


Assuntos
Sulfatos de Condroitina , Versicanas , Ratos , Animais , Versicanas/genética , Sulfatos de Condroitina/farmacologia , Ratos Wistar , Axônios/metabolismo , Regeneração Nervosa , RNA Interferente Pequeno/farmacologia
2.
Histochem Cell Biol ; 155(3): 355-367, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33170350

RESUMO

Syndecan-3 (SDC3) and Syndecan-4 (SDC4) are distributed throughout the nervous system (NS) and are favourable factors in motor neuron development. They are also essential for regulation of neurite outgrowth in the CNS. However, their roles in the reconstruction of the nodes of Ranvier after peripheral nerve injury (PNI) are still unclear. Present study used an in vivo model of end-to-side neurorrhaphy (ESN) for 1-3 months. The recovery of neuromuscular function was evaluated by grooming test. Expression and co-localization of SDC3, SDC4, and Nav1.6 channel (Nav1.6) at regenerating axons were detected by proximity ligation assay and confocal microscopy after ESN. Time-of-flight secondary ion mass spectrometry was used for imaging ions distribution on tissue. Our data showed that the re-clustering of sodium and Nav1.6 at nodal regions of the regenerating nerve corresponded to the distribution of SDC3 after ESN. Furthermore, the re-establishment of sodium and Nav1.6 correlated with the recovery of muscle power 3 months after ESN. This study suggested syndecans may involve in stabilizing Nav1.6 and further modulate the distribution of sodium at nodal regions after remyelination. The efficiency of sodium re-clustering was improved by the assistance of anionic syndecan, resulting in a better functional repair of PNI.


Assuntos
Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Procedimentos Neurocirúrgicos , Nós Neurofibrosos/metabolismo , Sódio/metabolismo , Sindecana-3/metabolismo , Animais , Masculino , Canal de Sódio Disparado por Voltagem NAV1.6/análise , Canal de Sódio Disparado por Voltagem NAV1.6/genética , Regeneração Nervosa , Ratos , Ratos Wistar , Sódio/análise , Sindecana-3/análise , Sindecana-3/genética
3.
Exp Physiol ; 106(8): 1814-1828, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34086374

RESUMO

NEW FINDINGS: What is the central question of this study? Imbalance of activities between GABAergic and glutamatergic systems is involved in epilepsy. It is not known whether simultaneously increasing GABAergic and decreasing glutamatergic activity using valproic acid and ceftriaxone, respectively, leads to better seizure control. What is the central question of this study? Ceftriaxone suppressed seizure and cognitive deficits and restored neuronal density and the number of newborn cells in the hippocampus in a rat model of epilepsy. Combined treatment with ceftriaxone and valproic acid showed additive effects in seizure suppression. ABSTRACT: The pathophysiology of epilepsy is typically considered as an imbalance between inhibitory GABA and excitatory glutamate neurotransmission. Valproic acid (Val), a GABA agonist, is one of the first-line antiepileptic drugs in the treatment of epilepsy, but it exhibits adverse effects. Ceftriaxone (CEF) elevates expression of glutamate transporter-1, enhances the reuptake of synaptic glutamate, increases the number of newborn cells and exhibits neuroprotective effects in animal studies. In this study, we evaluated effects of the combination of CEF and Val on behavioural and neuronal measures in a rat epilepsy model. Male Wistar rats were injected i.p. with pentylenetetrazol (35 mg/kg, every other day for 13 days) to induce the epilepsy model. Ceftriaxone (10 or 50 mg/kg), Val (50 or 100 mg/kg) or the combination of CEF and Val were injected daily after the fourth pentylenetetrazol injection for seven consecutive days. Epileptic rats exhibited seizure and impairments in motor and cognitive functions. Treatment with CEF and Val reduced the seizure and enhanced motor and cognitive functions in a dose-dependent manner. The combination of CEF (10 mg/kg) and Val (50 mg/kg) improved behaviours considerably. Histologically, compared with control animals, epileptic rats exhibited lower neuronal density and a reduction in hippocampal newborn cells but higher apoptosis in the basolateral amygdala, all of which were restored by the treatment with CEF, Val or the combination of CEF and Val. The study findings demonstrated that the combination of low doses of CEF and Val has beneficial effects on seizure suppression, neuroprotection and improvement in motor and cognitive functions in epilepsy.


Assuntos
Ceftriaxona , Epilepsia , Animais , Ceftriaxona/farmacologia , Ceftriaxona/uso terapêutico , Epilepsia/tratamento farmacológico , Masculino , Neurônios/fisiologia , Ratos , Ratos Wistar , Ácido Valproico/farmacologia , Ácido Valproico/uso terapêutico
4.
Int J Mol Sci ; 22(16)2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-34445125

RESUMO

Huntington's disease (HD) is an autosomal-dominant brain disorder caused by mutant huntingtin (mHtt). Although the detailed mechanisms remain unclear, the mutational expansion of polyglutamine in mHtt is proposed to induce protein aggregates and neuronal toxicity. Previous studies have shown that the decreased insulin sensitivity is closely related to mHtt-associated impairments in HD patients. However, how mHtt interferes with insulin signaling in neurons is still unknown. In the present study, we used a HD cell model to demonstrate that the miR-302 cluster, an embryonic stem cell-specific polycistronic miRNA, is significantly downregulated in mHtt-Q74-overexpressing neuronal cells. On the contrary, restoration of miR-302 cluster was shown to attenuate mHtt-induced cytotoxicity by improving insulin sensitivity, leading to a reduction of mHtt aggregates through the enhancement of autophagy. In addition, miR-302 also promoted mitophagy and stimulated Sirt1/AMPK-PGC1α pathway thereby preserving mitochondrial function. Taken together, these results highlight the potential role of miR-302 cluster in neuronal cells, and provide a novel mechanism for mHtt-impaired insulin signaling in the pathogenesis of HD.


Assuntos
Autofagia/genética , Proteína Huntingtina/genética , Doença de Huntington/genética , Resistência à Insulina/genética , Insulina/genética , MicroRNAs/genética , Transdução de Sinais/genética , Células Cultivadas , Regulação para Baixo/genética , Células-Tronco Embrionárias/patologia , Humanos , Mitocôndrias/genética , Mitofagia/genética , Neurônios/patologia
5.
Int J Mol Sci ; 19(9)2018 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-30149534

RESUMO

Huntington's disease (HD) is a progressive and fatal neurodegenerative disease caused by CAG repeat expansion in the coding region of huntingtin (HTT) protein. The accumulation of mutant HTT (mHTT) contributes to neurotoxicity by causing autophagy defects and oxidative stress that ultimately lead to neuronal death. Interestingly, epidemiologic studies have demonstrated that the prevalence of type-2 diabetes, a metabolic disease mainly caused by defective insulin signaling, is higher in patients with HD than in healthy controls. Although the precise mechanisms of mHTT-mediated toxicity remain unclear, the blockade of brain insulin signaling may initiate or exacerbate mHTT-induced neurodegeneration. In this study, we used an in vitro HD model to investigate whether neuronal insulin signaling is involved in mHTT-mediated neurotoxicity. Our results demonstrated that mHTT overexpression significantly impairs insulin signaling and causes apoptosis in neuronal cells. However, treatment with liraglutide, a GLP-1 analogue, markedly restores insulin sensitivity and enhances cell viability. This neuroprotective effect may be attributed to the contribution of the upregulated expression of genes associated with endogenous antioxidant pathways to oxidative stress reduction. In addition, liraglutide stimulates autophagy through AMPK activation, which attenuates the accumulation of HTT aggregates within neuronal cells. Our findings collectively suggest that liraglutide can rescue impaired insulin signaling caused by mHTT and that GLP-1 may potentially reduce mHTT-induced neurotoxicity in the pathogenesis of HD.


Assuntos
Proteína Huntingtina/genética , Insulina/metabolismo , Liraglutida/farmacologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Linhagem Celular Tumoral , Peptídeo 1 Semelhante ao Glucagon/análogos & derivados , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Humanos , Proteína Huntingtina/metabolismo , Hipoglicemiantes/farmacologia , Imuno-Histoquímica
6.
J Pineal Res ; 63(2)2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28480587

RESUMO

Prolonged exposure to gamma-hydroxybutyric acid (GHB) would cause drug intoxication in which impaired cognitive function results from enhanced hippocampal oxidative stress may serve as a major symptom in this deficiency. Considering melatonin possesses significant anti-oxidative efficacy, this study aimed to determine whether melatonin would successfully promote the nuclear factor erythroid 2-related factor 2 and antioxidant responsive element (Nrf2-ARE) signaling, depress oxidative stress, and rescue hippocampal bioenergetics and cognitive function following drug intoxication injury. Adolescent rats subjected to 10 days of GHB were received melatonin at doses of either 10 or 100 mg/kg. Time-of-flight secondary ion mass spectrometry, biochemical assay, quantitative histochemistry, [14 C]-2-deoxyglucose analysis, together with Morris water maze were employed to detect the molecular signaling, oxidative status, bioenergetic level, as well as the cognitive performances, respectively. Results indicated that in GHB-intoxicated rats, enhanced oxidative stress, increased cholesterol level, and decreased anti-oxidative enzymes activities were detected in hippocampal regions. Intense oxidative stress paralleled well with reduced bioenergetics and poor performance in behavioral testing. However, in rats treated with melatonin following GHB intoxication, all above parameters and cognitive function were gradually returned to nearly normal levels. Melatonin also remarkably promoted the translocation of Nrf2 from cytoplasm to nucleus in a dose-dependent manner, thereby increased the Nrf2-ARE signaling-related downstream anti-oxidative enzymes activities. As melatonin effectively rescues hippocampal bioenergetics through depressing the oxidative stress by promoting Nrf2-ARE molecular machinery, this study thus highlights for the first time that clinical use of melatonin may serve as a therapeutic strategy to improve the cognitive function in unsuspecting victims suffered from GHB intoxication injury.


Assuntos
Elementos de Resposta Antioxidante , Cognição/efeitos dos fármacos , Hipocampo , Melatonina/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Oxibato de Sódio/efeitos adversos , Animais , Comportamento Animal/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/patologia , Hipocampo/fisiopatologia , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar , Oxibato de Sódio/farmacologia
7.
Horm Behav ; 67: 38-47, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25461972

RESUMO

Amphetamine (AMPH)-induced appetite suppression has been attributed to its inhibition of neuropeptide Y (NPY)-containing neurons in the hypothalamus. This study examined whether hypothalamic cocaine- and amphetamine-regulated transcript (CART)-containing neurons and NPY Y1 receptor (Y1R) were involved in the action of AMPH. Rats were treated daily with AMPH for four days, and changes in feeding behavior and expression levels of NPY, CART, and POMC were assessed and compared. The results showed that both feeding behavior and NPY expression decreased during AMPH treatment, with the biggest reduction occurring on Day 2. By contrast, the expression of CART and melanocortin 3 receptor (MC3R), a member of the POMC neurotransmission, increased with the maximum response on Day 2, directly opposite to the NPY expression results. The intracerebroventricular infusion of NPY antisense or Y1R inhibitor both modulated AMPH-induced anorexia and the expression levels of MC3R and CART. The results suggest that in the hypothalamus both POMC- and CART-containing neurons participate in regulating NPY-mediated appetite control during AMPH treatment. These results may advance the knowledge of molecular mechanism of anorectic drugs.


Assuntos
Anfetamina/farmacologia , Depressores do Apetite/farmacologia , Regulação do Apetite/fisiologia , Hipotálamo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Neuropeptídeo Y/metabolismo , Receptores de Neuropeptídeo Y/metabolismo , Anfetamina/administração & dosagem , Animais , Depressores do Apetite/administração & dosagem , Regulação do Apetite/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Masculino , Oligonucleotídeos Antissenso/metabolismo , Fragmentos de Peptídeos/metabolismo , Pró-Opiomelanocortina/metabolismo , Ratos , Ratos Wistar
8.
Chin J Physiol ; 58(5): 322-31, 2015 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-26387656

RESUMO

Osteoporosis is a major disease associated with aging. We have previously demonstrated that diosgenin prevents osteoporosis in both menopause and D-galactose-induced aging rats. OXYS rats reveal an accelerated senescence and are used as a suitable model of osteoporosis. The aim of the present study was to analyze microarchitecture and morphological changes in femur of OXYS rats using morphological tests and microcomputed tomography scanning, and to evaluate the effects of oral administration of diosgenin at 10 and 50 mg/kg/day on femur in OXYS rats. The result showed that, compared with age-matched Wistar rats, the femur of OXYS rats revealed lower bone length, bone weight, bone volume, frame volume, frame density, void volume, porosity, external and internal diameters, cortical bone area, BV/TV, Tb.N, and Tb.Th, but higher Tb.Sp. Eight weeks of diosgenin treatment decreased porosity and Tb.Sp, but increased BV/TV, cortical bone area, Tb.N and bone mineral density, compared with OXYS rats treated with vehicle. These data reveal that microarchitecture and morphological changes in femur of OXYS rats showed osteoporotic aging features and suggest that diosgenin may have beneficial effects on aging-induced osteoporosis.


Assuntos
Dioscorea , Diosgenina/uso terapêutico , Fêmur/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Fitoterapia , Envelhecimento/patologia , Animais , Diosgenina/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Fêmur/patologia , Masculino , Osteoporose/patologia , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Wistar
9.
BMC Complement Altern Med ; 14: 491, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25510435

RESUMO

BACKGROUND: Wedelia chinensis is traditionally used as a hepatoprotective herb in Taiwan. The aim of this study was to evaluate the neuroprotective potential of W. chinensis. METHODS: An ethyl acetate extract of W. chinensis (EAW) was prepared and analyzed by HPLC. The neuroprotective potential of EAW was assessed by tert-butylhydroperoxide (t-BHP)-induced damage in PC12 cells and D-galactose-induced damage in mouse cortex. RESULTS: EAW exhibited potent radical scavenging property and highly contained luteolin and wedelolactone. EAW decreased t-BHP-induced reactive oxygen species (ROS) accumulation, cytotoxicity and apoptosis in PC12 cells. EAW and its major constituents blocked t-BHP-induced cytochrome C release and Bcl-2 family protein ratio change. EAW and its major constituents increased the endogenous antioxidant capacity evaluated by the binding activity assay of nuclear factor E2-related factor 2 (Nrf2) to antioxidant response element (ARE) and nuclear translocation of Nrf2 respectively in PC12 cells. Finally, EAW inhibited D-galactose-induced lipid peroxidation, apoptosis and neuron loss in the cerebral cortex of mice. CONCLUSION: These results demonstrate that W. chinensis has neuroprotective potential through blocking oxidative stress-induced damage and that luteolin and wedelolactone contribute to the protective action.


Assuntos
Apoptose/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Cumarínicos/farmacologia , Luteolina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Extratos Vegetais/farmacologia , Wedelia/química , Animais , Antioxidantes/análise , Antioxidantes/farmacologia , Encéfalo/metabolismo , Cumarínicos/análise , Citocromos c/metabolismo , Galactose , Peroxidação de Lipídeos/efeitos dos fármacos , Luteolina/análise , Medicina Tradicional Chinesa , Camundongos Endogâmicos ICR , Fator 2 Relacionado a NF-E2/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/análise , Fármacos Neuroprotetores/farmacologia , Células PC12 , Extratos Vegetais/química , Ratos , Espécies Reativas de Oxigênio/metabolismo , Taiwan , terc-Butil Hidroperóxido
10.
Chin J Physiol ; 57(3): 121-7, 2014 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-24826780

RESUMO

D-galactose is known to cause oxidative stress and induce aging-related diseases. Our previous study demonstrated that diosgenin can prevent osteoporosis in menopausal rats. The aim of the present study was to determine the effects of oral administration of diosgenin on bone loss in a D-galactose-induced aging rat model. Three groups of twelve-week-old male Wistar rats received a daily injection of D-galactose (150 mg/kg/day, i.p.) and orally administered diosgenin (0, 10, or 50 mg/kg/day) for eight weeks, while a control group received saline injection (1 ml/kg/day, i.p.), then the femurs were taken to measure mechanical and morphological properties. The results showed that frame volume and femur volume decreased and porosity and frame density increased in the D-galactose-induced aging rats compared to controls and that these effects were prevented by co-administration of diosgenin. This suggests that diosgenin might prevent bone loss during aging and provide beneficial effects in osteoporosis in the elderly.


Assuntos
Dioscorea/química , Diosgenina/farmacologia , Galactose/toxicidade , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Envelhecimento , Animais , Modelos Animais de Doenças , Fêmur/efeitos dos fármacos , Fêmur/patologia , Osteoporose/patologia , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Wistar
11.
Psychiatry Res ; 337: 115970, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38810537

RESUMO

Substance use disorder (SUD) exacerbates the impact of Long-COVID, particularly increasing the risk of taste and olfactory disorders. Analyzing retrospective cohort data from TriNetX and over 33 million records (Jan 2020-Dec 2022), this study focused on 1,512,358 participants, revealing that SUD significantly heightens the likelihood of experiencing taste disturbances and anosmia in Long-COVID sufferers. Results indicated that individuals with SUD face a higher incidence of sensory impairments compared to controls, with older adults and women being particularly vulnerable. Smokers with SUD were found to have an increased risk of olfactory and taste dysfunctions. The findings underscore the importance of early screening, diagnosis, and interventions for Long-COVID patients with a history of SUD, suggesting a need for clinicians to monitor for depression and anxiety linked to sensory dysfunction for comprehensive care.


Assuntos
COVID-19 , Transtornos do Olfato , Transtornos Relacionados ao Uso de Substâncias , Distúrbios do Paladar , Humanos , Feminino , COVID-19/complicações , COVID-19/epidemiologia , COVID-19/psicologia , Masculino , Estudos Retrospectivos , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , Pessoa de Meia-Idade , Adulto , Distúrbios do Paladar/etiologia , Distúrbios do Paladar/epidemiologia , Transtornos do Olfato/etiologia , Transtornos do Olfato/epidemiologia , Transtornos do Olfato/fisiopatologia , Idoso , Anosmia/etiologia , Anosmia/fisiopatologia , Anosmia/epidemiologia , Síndrome de COVID-19 Pós-Aguda , Estados Unidos/epidemiologia , Adulto Jovem
12.
Am J Cancer Res ; 13(7): 2998-3012, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37559985

RESUMO

Aberrant chondroitin sulfate (CS) accumulation in glioblastoma (GBM) tissue has been documented, but the role of excessive CS in GBM progression and whether it can be a druggable target are largely unknown. The aim of this study is to clarify the biological functions of CHST11 in GBM cells, and evaluate therapeutic effects of blocking CHST11-derived chondroitin 4-sulfate (C4S). We investigated the expression of CHST11 in glioma tissue by immunohistochemistry, and analyzed CHST11 associated genes using public RNA sequencing datasets. The effects of CHST11 on aggressive cell behaviors have been studied in vitro and in vivo. We demonstrated that CHST11 is frequently overexpressed in GBM tissue, promoting GBM cell mobility and modulating C4S on GBM cells. We further discovered that CSPG4 is positively correlated with CHST11, and CSPG4 involved in CHST11-mediated cell invasiveness. In addition, GBM patients with high expression of CHST11 and CSPG4 have a significantly shorter survival time. We examined the effects of treating C4S-specific binding peptide (C4Sp) as a therapeutic agent in vitro and in vivo. C4Sp treatment attenuated GBM cell invasiveness and, notably, improved survival rate of orthotopic glioma cell transplant mice. Our results propose a possible mechanism of CHST11 in regulating GBM malignancy and highlight a novel strategy for targeting aberrant chondroitin sulfate in GBM cells.

13.
Brain Behav Immun ; 26(2): 277-83, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21983278

RESUMO

Interleukin (IL)-2 regulates the immune response through the proliferation of activated T-cells and also exerts effects on the central nervous system (CNS). Alongside having marked neurobehavioral effects, IL-2 has been suggested to impact on various psychiatric disorders. The immune-CNS communication of IL-2 remains unclear, although, it is suggested that microglia are the source and target of IL-2. Here, we analyzed changes in brain metabolites following a peripheral IL-2 challenge and examined the contribution of microglia in mediating these effects. Rats were assessed by magnetic resonance spectroscopy (MRS) in a 9.4 T scanner for baseline metabolite levels in the prefrontal cortex (PFC) and the hippocampus. After 7 days animals were scanned again following a single injection of IL-2 (2.5 µg/kg) and then tested on the elevated plus-maze for the correlation of IL-2-induced brain metabolites and measures of anxiety. In another experiment CD25(+) microglia cells were determined. A separate group of rats was injected either with IL-2 or vehicle, and afterward the PFC and hippocampus were dissected and fluorescence activated cell sorting (FACS) analysis was performed. The MRS scans in the intra-individual study design showed a significant increase in myo-inositol in the analyzed regions. A significant correlation of anxiety-like measures and myo-inositol, a marker for microglia activity, was found in the hippocampus. The FACS analysis showed a significant increase in CD25(+) microglia in the hippocampus compared to controls. The results support the role of microglia as a mediator in the immune-CNS communication and the effects of peripheral IL-2.


Assuntos
Química Encefálica/efeitos dos fármacos , Interleucina-2/farmacologia , Microglia/fisiologia , Animais , Citometria de Fluxo , Hipocampo/química , Hipocampo/citologia , Hipocampo/efeitos dos fármacos , Inositol/análise , Imageamento por Ressonância Magnética , Microglia/efeitos dos fármacos , Neuroimagem , Córtex Pré-Frontal/química , Córtex Pré-Frontal/citologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Ratos Wistar , Ácido gama-Aminobutírico/análise
14.
Br J Nutr ; 107(12): 1787-92, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21929837

RESUMO

Subcutaneous (s.c.) D-galactose (DG) treatment has been shown to facilitate the development of biomarkers for Alzheimer's disease in C57BL/6J mice. The aim of the present study was to determine whether this treatment in young BALB/cJ mice, another mouse strain, enhanced oxidative stress to similar extents shown in older mice, and to further determine the effects of fructo-oligosaccharide (FO), a prebiotic fibre and vitamin E (antioxidant control) on the DG-induced oxidative damage of lipids, proteins and mitochondrial DNA, and erythrocyte antioxidant enzyme activities. Mice (12 weeks of age, n 40) were divided into four groups: vehicle (s.c. saline)+control (modified rodent chow); DG (s.c. 1·2 g/kg body weight)+control; DG+FO (5 %, w/w); DG+vitamin E (α-tocopherol, 0·2 %). Then, the animals were killed after 52 d of treatment. Another natural ageing (NA) group without any injection was killed at 47 weeks of age, which served as an aged control. The results indicated that the DG treatment enhanced malonaldehyde dimethyl acetal (MDA) levels in the plasma, liver and cerebral cortex, and protein carbonyl levels in the liver and hippocampus to similar levels shown in the NA group. FO, similar to α-tocopherol, systemically normalised DG-induced elevations in the levels of MDA in the plasma, liver and cerebral cortex, protein carbonyls in the liver and hippocampus, hepatic mitochondrial 8-oxo-deoxyguanosine and erythrocyte superoxide dismutase activity. In conclusion, the s.c. DG treatment in younger BALB/cJ mice resembled the oxidative status in older mice. FO supplementation systemically prevented DG-induced oxidative stress, probably through its fermentation products and prebiotic effect.


Assuntos
Antioxidantes/farmacologia , Encéfalo/efeitos dos fármacos , Galactose/efeitos adversos , Fígado/efeitos dos fármacos , Oligossacarídeos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Prebióticos , 8-Hidroxi-2'-Desoxiguanosina , Fatores Etários , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Animais , Antioxidantes/metabolismo , Encéfalo/metabolismo , Desoxiguanosina/análogos & derivados , Desoxiguanosina/metabolismo , Fibras na Dieta/farmacologia , Suplementos Nutricionais , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Galactose/administração & dosagem , Injeções Subcutâneas , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Masculino , Malondialdeído/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Oxirredução , Carbonilação Proteica/efeitos dos fármacos , Superóxido Dismutase/metabolismo , Vitamina E/farmacologia
15.
Chin J Physiol ; 55(4): 245-52, 2012 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-23282165

RESUMO

Complete vascular ring is a term describing a group of congenital aortic arch abnormalities that is often observed in infancy and leads to tracheoesophageal compression and airway obstruction. We investigated the effects of chronic resistive airway loading on anxiety and learning behavior in Wistar rats. The trachea were obstructed by a circumferential tracheal band to increase respiratory esophageal pressure. All of the rats were subjected to the elevated plus-maze test and the active avoidance test at 2 or 4 weeks after the obstruction surgery. One set of rats received surgical relief of the tracheal obstruction on week 2 or 3 after obstruction. At 4, but not 2, weeks after tracheal obstruction, the rats showed impairment of learning in the active avoidance test and this impairment was prevented by surgical relief of tracheal obstruction performed on week 2, but not week 3. In contrast, anxiety-like behavior in the elevated plus-maze test was not affected at either 2 or 4 weeks after tracheal obstruction. Body weight was not affected by tracheal obstruction and no differences were seen in arterial blood gases after 4 weeks of tracheal obstruction. These results suggest that chronic tracheal obstruction causes learning deficits and that surgical intervention is necessary and should be performed as early as possible to prevent long-term sequelae.


Assuntos
Obstrução das Vias Respiratórias , Animais , Ratos , Ratos Wistar
16.
Chin J Physiol ; 55(2): 91-100, 2012 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-22559733

RESUMO

Neuroimmune system is involved in communication between the endocrine and nervous systems, which may take part in the effects of dioscorea, reversing changes of anxiety-like behavior and interleukin (IL)-2 levels in the brains of ovariectomized (OVX) rats. This study was aimed at evaluating administration of diosgenin, an ingredient of dioscorea, on neuroimmune and behavioral functions in OVX animals. One month after ovariectomy, female Wistar rats were fed daily with diosgenin (0, 10, 50 or 100 mg/kg/day) and the elevated plus-maze and learned helplessness tests were used to measure anxiety-like and depressive behaviors after 23 and 24 days of diosgenin treatment, respectively. In the learned helplessness test, the rats needed to cross from one compartment of the shuttle box to the opposite compartment to avoid or escape the shock. If the rat failed to escape the shock in 10 sec, a "failure" was recorded. Two days after the behavioral tests, the brain was removed to measure levels of IL-2 which was used as an indicator of neuroimmune function. Anxiety-like behavior in the OVX rats was not affected by diosgenin treatment. However, avoidance behavior in the learned helplessness test in the OVX rats with high anxiety (HA) levels was improved by treatment with diosgenin at the dosage of 10mg/kg/day. Interestingly, the number of failures in the same test was increased when the dosage of diosgenin was increased to 50 mg/kg/day, and this was accompanied by an increase in IL-2 levels in the pituitary gland. In addition, treatment with 100 mg/kg/day of diosgenin resulted in decreased IL-2 levels in the amygdala and prefrontal cortex of the OVX rats with low anxiety levels, and in increased IL-2 levels in the amygdala of OVX HA rats. These results show that chronic diosgenin treatment influences IL-2 levels in the brain of OVX rats and affects depressive behavior in OVX HA rats, but not OVX low anxiety rats.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Diosgenina/farmacologia , Interleucina-2/metabolismo , Menopausa/fisiologia , Ovariectomia , Animais , Ansiedade/tratamento farmacológico , Ansiedade/fisiopatologia , Comportamento Animal/fisiologia , Encéfalo/metabolismo , Depressão/tratamento farmacológico , Depressão/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Desamparo Aprendido , Aprendizagem em Labirinto/efeitos dos fármacos , Aprendizagem em Labirinto/fisiologia , Neuroimunomodulação/efeitos dos fármacos , Neuroimunomodulação/fisiologia , Ratos , Ratos Wistar
17.
Biomolecules ; 12(10)2022 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-36291547

RESUMO

Diabetic neuropathy (DN) is a type of sensory nerve damage that can occur in patients with diabetes. Although the understanding of pathophysiology is incomplete, DN is often associated with structural and functional alterations of the affected neurons. Among all possible causes of nerve damage, Schwann cells (SCs) are thought to play a key role in repairing peripheral nerve injury, suggesting that functional deficits occurring in SCs may potentially exhibit their pathogenic roles in DN. Therefore, elucidating the mechanisms that underlie this pathology can be used to develop novel therapeutic targets. In this regard, glucagon-like peptide-1 receptor agonists (GLP-1 RAs) have recently attracted great attention in ameliorating SCs' dysfunction. However, the detailed mechanisms remain uncertain. In the present study, we investigated how GLP-1 RA Liraglutide protects against RSC96 SCs dysfunction through a diabetic condition mimicked by high glucose and high free fatty acid (FFA). Our results showed that high glucose and high FFAs reduced the viability of RSC96 SCs by up to 51%, whereas Liraglutide reduced oxidative stress by upregulating antioxidant enzymes, and thus protected cells from apoptosis. Liraglutide also inhibited NFκB-mediated inflammation, inducing SCs to switch from pro-inflammatory cytokine production to anti-inflammatory cytokine production. Moreover, Liraglutide upregulated the production of neurotrophic factors and myelination-related proteins, and these protective effects appear to be synergistically linked to insulin signaling. Taken together, our findings demonstrate that Liraglutide ameliorates diabetes-related SC dysfunction through the above-mentioned mechanisms, and suggest that modulating GLP-1 signaling in SCs may be a promising strategy against DN.


Assuntos
Neuropatias Diabéticas , Liraglutida , Humanos , Liraglutida/farmacologia , Liraglutida/metabolismo , Liraglutida/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/metabolismo , Ácidos Graxos não Esterificados , Antioxidantes/farmacologia , Células de Schwann/metabolismo , Neuropatias Diabéticas/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/metabolismo , Insulina/metabolismo , Inflamação/metabolismo , Glucose/metabolismo , Fatores de Crescimento Neural/farmacologia , Citocinas/metabolismo
18.
Steroids ; 179: 108980, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35157911

RESUMO

BACKGROUND: The anti-apoptotic effects of diosgenin, a steroid saponin, on hearts in female with estrogen deficiency have been less studied. This study aimed to evaluate the anti-apoptotic effects of diosgenin on cardiac widely dispersed apoptosis in a bilateral ovariectomized animal model. METHODS: A total of 60 female Wistar rats, aged 6-7 months, were divided into the sham-operated group (Sham), bilateral ovariectomized rats for 2 months, and ovariectomized rats administered with 0, 10, 50, or 100 mg/kg diosgenin daily (OVX, OVX 10, OVX 50, and OVX 100, respectively) in the second month. The excised hearts were analyzed by H&E staining, TUNEL(+) assays and Western Blot. RESULT: Cardiac TUNEL(+) apoptotic cells, the levels of Fas ligand, Fas death receptors, Fas-associated death domain, active caspase-8, and active caspase-3 (FasL/Fas-mediated pathways) as well as the levels of Bax, Bad, Bax/Bcl2, Bad/p-Bad, cytosolic Cytochrome c, active caspase-9, and active caspase-3 (mitochondria-initiated pathway) were increased in OVX compared with Sham group but those were decreased in OVX 50 compared with OVX. CONCLUSION: Diosgenin appeared to prevent or suppress ovariectomy-induced cardiac FasL/Fas-mediated and mitochondria-initiated apoptosis. These findings might provide one of the possible therapeutic approaches of diosgenin for potentially preventing cardiac apoptosis in women after bilateral ovariectomy or women with estrogen deficiency.


Assuntos
Diosgenina , Animais , Apoptose , Diosgenina/metabolismo , Diosgenina/farmacologia , Feminino , Coração , Humanos , Miocárdio/metabolismo , Ovariectomia , Ratos , Ratos Wistar , Receptor fas/metabolismo
19.
Behav Brain Res ; 435: 114035, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-35926562

RESUMO

Dementia with Lewy bodies (DLB), a highly prevalent neurodegenerative disorder, causes motor and cognitive deficits. The main pathophysiologies of DLB are glutamate excitotoxicity and accumulation of Lewy bodies comprising α-synuclein (α-syn) and ß-amyloid (Aß). Amitriptyline (AMI) promotes expression of glutamate transporter-1 and glutamate reuptake. In this study, we measured the effects of AMI on behavioral and neuronal function in a DLB rat model. We used rivastigmine (RIVA) as a positive control. To establish the DLB rat model, male Wistar rats were stereotaxically injected with recombinant adenoassociated viral vector with the SNCA gene (10 µg/10 µL) and Aß (5 µg/2.5 µL) into the left ventricle and prefrontal cortex, respectively. AMI (10 mg/kg/day, i.p.), RIVA (2 mg/kg/day, i.p.), or saline was injected intraperitoneally after surgery. From the 29th day, behavioral tests were performed to evaluate the motor and cognitive functions of the rats. Immunohistochemical staining was used to assess neuronal changes. We measured the α-syn level, number of newborn cells, and neuronal density in the hippocampus and in the nigrostriatal dopaminergic system. The DLB group exhibited deficit in object recognition. Both the AMI and RIVA treatments reversed these deficits. Histologically, the DLB rats exhibited cell loss in the substantia nigra pars compacta and in the hippocampal CA1 area. AMI reduced this cell loss, but RIVA did not. In addition, the DLB rats exhibited a lower number of newborn cells and higher α-syn levels in the dentate gyrus (DG). AMI did not affect α-syn accumulation but recovered neurogenesis in the DG of the rats, whereas RIVA reversed the α-syn accumulation but did not affect neurogenesis in the rats. We suggest that AMI may have potential for use in the treatment of DLB.


Assuntos
Doença por Corpos de Lewy , Amitriptilina , Animais , Cognição , Glutamatos , Doença por Corpos de Lewy/tratamento farmacológico , Doença por Corpos de Lewy/metabolismo , Doença por Corpos de Lewy/patologia , Masculino , Ratos , Ratos Wistar , alfa-Sinucleína/metabolismo
20.
Cells ; 10(12)2021 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-34944101

RESUMO

Chondroitin sulfate (CS) is a major component of the extracellular matrix found to be abnormally accumulated in several types of cancer tissues. Previous studies have indicated that CS synthases and modification enzymes are frequently elevated in human gliomas and are associated with poor prognosis. However, the underlying mechanisms of CS in cancer progression and approaches for interrupting its functions in cancer cells remain largely unexplored. Here, we have found that CS was significantly enriched surrounding the vasculature in a subset of glioma tissues, which was akin to the perivascular niche for cancer-initiating cells. Silencing or overexpression of the major CS synthase, chondroitin sulfate synthase 1 (CHSY1), significantly regulated the glioma cell invasive phenotypes and modulated integrin expression. Furthermore, we identified CD44 as a crucial chondroitin sulfate proteoglycan (CSPG) that was modified by CHSY1 on glioma cells, and the suppression of CS formation on CD44 by silencing the CHSY1-inhibited interaction between CD44 and integrin ß1 on the adhesion complex. Moreover, we tested the CS-specific binding peptide, resulting in the suppression of glioma cell mobility in a fashion similar to that observed upon the silencing of CHSY1. In addition, the peptide demonstrated significant affinity to CD44, promoted CD44 degradation, and suppressed integrin ß1 expression in glioma cells. Overall, this study proposes a potential regulatory loop between CS, CD44, and integrin ß1 in glioma cells, and highlights the importance of CS in CD44 stability. Furthermore, the targeting of CS by specific binding peptides has potential as a novel therapeutic strategy for glioma.


Assuntos
Sulfatos de Condroitina/metabolismo , Glioma/metabolismo , Glioma/patologia , Receptores de Hialuronatos/metabolismo , Integrina beta1/metabolismo , Animais , Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Regulação Neoplásica da Expressão Gênica , Glioma/irrigação sanguínea , Glioma/genética , Glucuronosiltransferase/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Enzimas Multifuncionais/metabolismo , N-Acetilgalactosaminiltransferases/metabolismo , Gradação de Tumores , Invasividade Neoplásica , Peptídeos/metabolismo , Fenótipo , Proteólise
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA