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1.
Pak J Pharm Sci ; 34(3): 909-914, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34602413

RESUMO

N-Methyl-D-aspartate receptor (NMDAR)-induced antioxidation is a significant cause of neuronal injury after ischemic stroke. In a previous work, we verified the neuroprotective roles of geniposide during tMCAO in vivo. However, it remains unknown whether geniposide ameliorates injury to hippocampal neurons during Ischemic Long Term Potentiation (iLTP) induction in vitro. After induction of cells oxygen-glucose deprivation or hydrogen peroxide, the protection of geniposide evaluated by MTT assay and electrophysiological tests. In this study, we suggested neuronal cell apoptosis was attenuated by geniposide. Furthermore, field excitatory postsynaptic potentials (fEPSCs) following postischemic LTP were assessed by electrophysiological tests. Finally, we determined that medium and high doses of geniposide attenuated oxidative stress insult and improved iLTP. Importantly, these effects were abolished by cotreatment with geniposide and the GluN2A antagonist NVP. In contrast, the GluN2B inhibitor ifenprodil failed to have an effect. In conclusion, we suggest for the first time that treatment with geniposide can attenuate postischemic LTP induction in a concentration-dependent manner. We infer that GluN2A-containing NMDARs are involved in the neuroprotection induced by geniposide treatment in ischemia.

2.
Mater Sci Eng C Mater Biol Appl ; 128: 112354, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474902

RESUMO

In this paper, silk fibroin (SF) porous microcarriers containing strontium were constructed as injectable bone tissue engineering vehicles. The effects of SF concentration and strontium content on micromorphology, element distribution, strontium ion release and cellular behavior of the constructed microcarriers were investigated. The microcarriers with an open interconnected pore can be fabricated by controlling the concentration of SF. The strontium functionalized SF microcarriers showed the sustained release of strontium ion and allowed bone mesenchymal stem cells (BMSCs) to attach, proliferate and secrete extracellular matrix. Furthermore, the strontium functionalized SF microcarriers improved the osteogenic capability of BMSCs in vitro compared with those microcarriers without sustained release of strontium ion. This study presents a valuable approach to fabricate polymeric microcarriers with the capability of sustained release of strontium ion that show potential in bone tissue engineering applications.


Assuntos
Fibroínas , Diferenciação Celular , Osteogênese , Porosidade , Estrôncio , Engenharia Tecidual , Tecidos Suporte
3.
Aging (Albany NY) ; 13(5): 7314-7329, 2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33639616

RESUMO

The pedunculopontine nucleus (PPN) undergoes significant anatomic and electrophysiological alterations in Parkinson's disease (PD), severely impacting locomotion. However, the effect of 6-hydroxydopamine (6-OHDA) lesion and levodopa (L-DOPA) therapy on the relationships between spike activities and local field potential (LFP) within the PPN is not well-understood. Synchronisation between the spike activity of individual neurones and LFP of neuronal ensembles is a crucial problem in the pathogenesis of PD. In this study, LFP signals and spikes in the PPN of rats in control, lesioned, and L-DOPA groups were recorded synchronously with a multi-unit electrical signal acquisition system and analysed for their coherence value, spike-field coherence, and phase-lock relationship. The spike-LFP relationship in the PPN was markedly increased in specific frequency bands because of the 6-OHDA lesion but differed depending on the animal locomotion state and neuronal type. L-DOPA had a limited therapeutic effect on the 6-OHDA-induced increase in the coherence value. Our study demonstrates that the PPN spike-LFP relationship is involved in the pathogenesis of PD and is critical for the effects of L-DOPA, providing a basis for the clinical treatment of refractory PD symptoms.


Assuntos
Potenciais de Ação/efeitos dos fármacos , Levodopa/uso terapêutico , Transtornos Parkinsonianos/tratamento farmacológico , Núcleo Tegmental Pedunculopontino/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/fisiologia , Locomoção/efeitos dos fármacos , Locomoção/fisiologia , Masculino , Oxidopamina/farmacologia , Transtornos Parkinsonianos/fisiopatologia , Núcleo Tegmental Pedunculopontino/fisiopatologia , Ratos , Ratos Wistar
4.
Front Psychiatry ; 11: 295, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351418

RESUMO

Premenstrual dysphoric disorder (PMDD) is a severe form of premenstrual syndrome (PMS), a common mental health disturbance associated with several periodic psychological symptoms in women. Selective serotonin reuptake inhibitors (SSRIs) are the first-line treatment for PMS/PMDD patients; however, side effects are inevitable, especially in long-term treatment. In previous studies, the natural compound paeonol in Moutan Cortex was found to play effective roles in central nervous system disorders with its anti-inflammatory, anti-oxidant, and neuroprotective effects. Consequently, we assume that paeonol might produce positive effects in the treatment of PMS/PMDD. In this study, the open-field test (OFT) and elevated plus maze (EPM) and light dark box (LDB) tests were performed in mice to determine the optimal dose of paeonol for treating anxiety. Then, paeonol was used to treat the progesterone withdrawal (PWD) and resident intruder paradigm (RIP) rat models of PMDD. Using these two reliable models, the OFT and EPM, LDB, and composite aggressive tests were performed to evaluate the effect of the drug on behavioural symptoms of PMDD. From the dosage screening results, the optimal anti-anxiety dose of paeonol was identified as 17.5 mg/kg/d for 7 days. With regard to the effect of paeonol on PMDD rat models, a significantly improvement was found in the behavioural symptoms, but the effective dose varied in different models. For the PWD model rats, treatment with 6.05 mg/kg paeonol could significantly improve anxiety and irritability, while that with 24.23 mg/kg paeonol resulted in anxiety-like effects in behavioural tests. In RIP model rats, treatment with 12.11 mg/kg paeonol demonstrated excellent effects in improving anxiety, particularly irritable emotional behaviour. In conclusion, our study indicates that paeonol is a potential therapeutic compound for PMS/PMDD; it is a drug option that helps establish dosage guidance for treatment of this condition.

5.
Front Neurosci ; 13: 1034, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31616246

RESUMO

The pedunculopontine nucleus (PPN) is composed of a morphologically and neurochemically heterogeneous population of neurons, which is severely affected by Parkinson's disease (PD). However, the role of each subtype of neurons within the PPN in the pathophysiology of PD has not been completely elucidated. In this study, we present the discharge profiles of three classified subtypes of PPN neurons and their alterations after 6-hydroxydopamine (6-OHDA) lesion. Following 6-OHDA lesion, the spike timing of the Type II (GABAergic) and Type III (glutamatergic) neurons had phase-lock with the oscillations in the delta and beta band frequency range in the PPN, respectively. Morphological evidence has shown distinct alteration in three kinds of neurons after 6-OHDA lesion. These findings revealed that the changes in the firing characteristics of neurons in PPN in hemi-parkinsonism rats are closely associated with damaged neuronal morphology, which would make contributions to the divergence of dysfunctions in Parkinsonism.

6.
Neuroscience ; 404: 470-483, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30710670

RESUMO

The pedunculopontine nucleus (PPN) shows altered electrophysiological and anatomic characteristics in Parkinson's disease (PD), but little is known about the effect of 6-hydroxydopamine (6-OHDA) lesion and levodopa (L-DOPA) therapy on the relationship between spike and local field potential (LFP) activities in the PPN and motor cortex. Aiming to investigate this, synchronous spike and LFP signals in the PPN and primary motor cortex (M1) were recorded. The spike-LFP relationship was evaluated using coherence analysis, phase-lock and spike-field coherence (SFC). The results suggested that 6-OHDA lesion had a significant effect on the spike-LFP relationship between the PPN and M1 in rats under a rest or locomotion state. The significantly altered frequency bands varied across different neuron types and animal activity states. In addition, the altered coherence values between PPN spike and M1 LFP were refractory to long-term L-DOPA therapy although all other changes could be reversed by this drug treatment. All results provided evidence of the spike-LFP relationship between the PPN and M1 in PD, revealing some network mechanisms of the cortico-basal ganglia circuitry and PPN, which might be an underlying candidate for PD pathophysiology and therapy.


Assuntos
Potenciais de Ação/fisiologia , Modelos Animais de Doenças , Córtex Motor/fisiologia , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/fisiopatologia , Núcleo Tegmental Pedunculopontino/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Levodopa/farmacologia , Levodopa/uso terapêutico , Masculino , Córtex Motor/efeitos dos fármacos , Oxidopamina/toxicidade , Transtornos Parkinsonianos/tratamento farmacológico , Núcleo Tegmental Pedunculopontino/efeitos dos fármacos , Ratos , Ratos Wistar
7.
Medicine (Baltimore) ; 97(34): e11595, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30142753

RESUMO

In this study, we tried to describe the characteristics of pain and explore the association between the incidence of pain and abnormal laboratory test results in patients during the acute phase of Guillain-Barré syndrome (GBS).This retrospective cohort study enrolled 252 patients with GBS who were in the acute phase of the disease. We collected data regarding the location and type of pain, the onset time, clinical variables and laboratory tests, including the levels of uric acid (UA), albumin, cerebrospinal fluid protein (CSFP), cerebrospinal fluid glucose (CSFG), fasting glucose upon admission, and blood creatinine. The pain descriptors were compared to the severity of disease and laboratory examination results.Around 34.5% of the patients reported pain during the acute phase of GBS. Pain was negatively correlated with the disease severity during the acute phase. In total, 29 of the 87 (33.3%) patients reported pain during the 2 weeks preceding the onset of weakness. The concentration of CSFP was positively associated with the incidence of pain, while the concentrations of UA and albumin were not correlated with the incidence of pain.We found that 33.3% of the GBS patients experienced pain within 2 weeks of onset, and the pain was positively associated with CSFP concentration but was not correlated with disease severity.


Assuntos
Síndrome de Guillain-Barré/complicações , Dor/epidemiologia , Doença Aguda , Adulto , Idoso , Biomarcadores/metabolismo , Proteínas do Líquido Cefalorraquidiano/metabolismo , Feminino , Síndrome de Guillain-Barré/metabolismo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
8.
Behav Brain Res ; 315: 1-9, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27515286

RESUMO

Levodopa (l-DOPA) has been proved to reverse the pathologic neuron activities in many brain regions related to Parkinson's disease (PD). But little is known about the effect of l-DOPA on the altered electrophysiological coherent activities between pedunculopontine nucleus (PPN) and motor cortex. To investigate this, local field potentials (LFPs) of PPN and primary motor cortex (M1) were recorded simultaneously in control, 6-hydroxydopamine lesioned and lesioned rats with l-DOPA chronic treatment. The results revealed that in resting state, chronic l-DOPA treatment could correct the suppressed power of LFPs in PPN and M1 in low-frequency band (1-7Hz) and the enhanced power in high-frequency band (7-70Hz in PPN and 12-70Hz in M1) of lesioned rats. In locomotor state, l-DOPA treatment could correct the alterations in most of frequency bands except the δ band in PPN and α band in M1. Moreover, l-DOPA could also reverse the altered coherent relationships caused by dopamine depletion in resting state between PPN and M1 in ß band. And in locomotor state, l-DOPA had therapeutic effect on the alterations in δ and ß bands but not in the α band. These findings provide evidence that l-DOPA can reverse the altered LFP activities in PPN and M1 and their relationships in a rat model of PD, which contributes to better understanding the electrophysiological mechanisms of the pathophysiology and therapy of PD.


Assuntos
Antiparkinsonianos/farmacologia , Potenciais Evocados/efeitos dos fármacos , Levodopa/farmacologia , Córtex Motor/efeitos dos fármacos , Doença de Parkinson/patologia , Núcleo Tegmental Pedunculopontino/efeitos dos fármacos , Animais , Antiparkinsonianos/uso terapêutico , Benserazida/farmacologia , Benserazida/uso terapêutico , Condicionamento Operante/efeitos dos fármacos , Modelos Animais de Doenças , Análise de Fourier , Levodopa/uso terapêutico , Locomoção/efeitos dos fármacos , Masculino , Oxidopamina/toxicidade , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/etiologia , Ratos , Ratos Wistar , Fatores de Tempo
9.
Neuroscience ; 330: 57-71, 2016 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-27238892

RESUMO

Several studies have suggested that the thalamic centromedian-parafascicular (CM/PF or the PF in rodents) is implicated in the pathophysiology of Parkinson's disease (PD). However, inconsistent changes in the neuronal firing rate and pattern have been reported in parkinsonian animals. To investigate the impact of a dopaminergic cell lesion on PF extracellular discharge in behaving rats, the PF neural activities in the spike and local field potential (LFP) were recorded in unilaterally 6-hydroxydopamine- (6-OHDA) lesioned and neurologically intact control rats during rest and limb movement. During rest, the two PF neuronal subtypes was less spontaneously active, with no difference in the spike firing rates between the control and lesioned rats; only the lesioned rats reshaped their spike firing pattern. Furthermore, the simultaneously recorded LFP in the lesioned rats exhibited a significant increase in power at 12-35 and 35-70Hz and a decrease in power at 0.7-12Hz. During the execution of a voluntary movement, two subtypes of PF neurons were identified by a rapid increase in the discharge activity in both the control and lesioned rats. However, dopamine lesioning was associated with a decrease in neuronal spiking fire rate and reshaping in the firing pattern in the PF. The simultaneously recorded LFP activity exhibited a significant increase in power at 12-35Hz and a decrease in power at 0.7-12Hz compared with the control rats. These findings indicate that 6-OHDA induces modifications in PF spike and LFP activities in rats during rest and movement and suggest that PF dysfunction may be an important contributor to the pathophysiology of parkinsonian motor impairment.


Assuntos
Potenciais de Ação/fisiologia , Núcleos Intralaminares do Tálamo/fisiopatologia , Atividade Motora/fisiologia , Neurônios/fisiologia , Transtornos Parkinsonianos/fisiopatologia , Animais , Dopamina/metabolismo , Lateralidade Funcional , Imuno-Histoquímica , Núcleos Intralaminares do Tálamo/patologia , Masculino , Microeletrodos , Neurônios/patologia , Oxidopamina , Transtornos Parkinsonianos/patologia , Ratos Wistar , Fatores de Tempo
10.
Behav Brain Res ; 305: 57-64, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26924016

RESUMO

The pedunculopontine nucleus (PPN) is a new deep brain stimulation target for treating Parkinson's disease (PD). But the alterations of the PPN electrophysiological activities in PD are still debated. To investigate these potential alterations, extracellular single unit and local field potential (LFP) activities in the PPN were recorded in unilateral hemispheric 6-hydroxydopamine (6-OHDA) lesioned rats and in control rats, respectively. The spike activity results revealed two types of neurons (Type I and Type II) with distinct electrophysiological characteristics in the PPN. Both types of neurons had increased firing rate and changed firing pattern in lesioned rats when compared to control rats. Specifically, Type II neurons showed an increased firing rate when the rat state was switched from rest to locomotion. The LFP results demonstrated that lesioned rats had lower LFP power at 0.7-12Hz and higher power at 12-30Hz than did control animals in either resting or locomotor state. These findings provide a better understanding of the effects of 6-OHDA lesion on neuronal activities in the PPN and also provide a proof of the link between this structure and locomotion, which contributes to better understanding the mechanisms of the PPN functioning in the pathophysiology of PD.


Assuntos
Potenciais de Ação/fisiologia , Neurônios/fisiologia , Doença de Parkinson/patologia , Núcleo Tegmental Pedunculopontino/patologia , Potenciais de Ação/efeitos dos fármacos , Adrenérgicos/toxicidade , Animais , Modelos Animais de Doenças , Estimulação Elétrica , Masculino , Feixe Prosencefálico Mediano/lesões , Neurônios/efeitos dos fármacos , Oxidopamina/toxicidade , Doença de Parkinson/etiologia , Doença de Parkinson/fisiopatologia , Desempenho Psicomotor/efeitos dos fármacos , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Tirosina 3-Mono-Oxigenase/metabolismo
11.
Gastroenterol Res Pract ; 2016: 4618672, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26843857

RESUMO

Background. Until now, the effect of arginine vasopressin (AVP) in the DMV on gastric motility and the possible modulating pathway between the DMV and the gastrointestinal system remain poorly understood. Objectives. We aimed to explore the role of AVP in the DMV in regulating gastric motility and the possible central and peripheral pathways. Material and Methods. Firstly, we microinjected different doses of AVP into the DMV and investigated its effects on gastric motility in rats. Then, the possible central and peripheral pathways that regulate gastric motility were also discussed by microinjecting SR49059 (a specific AVP receptor antagonist) into the DMV and intravenous injection of hexamethonium (a specific neuronal nicotinic cholinergic receptor antagonist) before AVP microinjection. Results. Following microinjection of AVP (180 pmol and 18 pmol) into the DMV, the gastric motility (including total amplitude, total duration, and motility index of gastric contraction) was significantly inhibited (P < 0.05). Moreover, the inhibitory effect of AVP (180 pmol) on gastric motility could be blocked completely by both SR49059 (320 pmol) and hexamethonium (8 µmol). Conclusions. It is concluded that AVP inhibits the gastric motility by acting on the specific AVP receptor in the DMV, with the potential involvement of the parasympathetic preganglionic cholinergic fibers.

13.
J Neurol Sci ; 348(1-2): 231-40, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25542079

RESUMO

The involvement of dopamine (DA) neuron loss in the etiology of Parkinson's disease has been well documented. The neural mechanisms underlying the effects of DA loss and the resultant motor dysfunction remain unknown. To gain insights into how loss of DA disrupts the electrical processes in the cortico-subcortical network, the present study explores the effects of DA neuron depletion on electrical activity in the primary motor cortex (M1), on the external and the internal segment of the globus pallidus (GPe and GPi respectively), and on their temporal relationships. Comparison of local field potentials (LFPs) in these brain regions from unilateral hemispheric DA neuron depleted rats and neurologically intact rats revealed that the spectrum power of LFPs in 12-70Hz (for M1, and GPe) and in 25-40Hz (for GPi) was significantly greater in the DA depleted rats than that in the control group. These changes were associated with a shortening of latency in LFP activities between M1 and GPe, from several hundred milliseconds in the intact animals to close to zero in the DA depleted animals. LFP oscillations in M1 were significantly more synchronized with those in GPe in the DA depleted rats compared with those in the control rats. By contrast, the synchronization of oscillation in LFP activities between M1 and GPi did not differ between the DA depleted and intact rats. Not surprisingly, rats that had DA neuron depletion spent more time along the ladder compared with the control rats. These data suggest that enhanced oscillatory activity and increased synchronization of LFPs may contribute to movement impairment in the rat model of Parkinson's disease.


Assuntos
Comportamento Animal/fisiologia , Neurônios Dopaminérgicos/patologia , Fenômenos Eletrofisiológicos/fisiologia , Globo Pálido/fisiopatologia , Córtex Motor/fisiopatologia , Doença de Parkinson/fisiopatologia , Animais , Modelos Animais de Doenças , Masculino , Ratos , Ratos Wistar
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