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1.
Acta Biomater ; 145: 200-209, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35430336

RESUMO

Gemcitabine (GEM) is among the most used chemotherapies for advanced malignancies including non-small cell lung cancer. The clinical efficacy of GEM is, however, downplayed by its poor bioavailability, short half-life, drug resistance, and dose-limiting toxicities (e.g. myelosuppression). In spite of many approaches exploited to improve the efficacy and safety of GEM, limited success was achieved. The short A6 peptide (sequence: Ac-KPSSPPEE-NH2) is clinically validated for specific binding to CD44 on metastatic tumors. Here, we designed a robust and CD44-specific GEM nanotherapeutics by encapsulating hydrophobic phosphorylated gemcitabine prodrug (HPG) into the core of A6 peptide-functionalized disulfide-crosslinked micelles (A6-mHPG), which exhibited reduction-triggered HPG release and specific targetability to CD44 overexpressing tumor cells. Interestingly, A6 greatly enhanced the internalization and inhibitory activity of micellar HPG (mHPG) in CD44 positive A549 cells, and increased its accumulation in A549 cancerous lung, leading to potent repression of orthotopic tumor growth, depleted toxicity, and marked survival benefits compared to free HPG and mHPG (median survival time: 59 days versus 30 and 45 days, respectively). The targeted delivery of gemcitabine prodrug with disulfide-crosslinked biodegradable micelles appears to be a highly appealing strategy to boost gemcitabine therapy for advance tumors. STATEMENT OF SIGNIFICANCE: Gemcitabine (GEM) though widely used in clinics for treating advanced tumors is associated with poor bioavailability, short half-life and dose-limiting toxicities. Development of clinically translatable GEM formulations to improve its anti-tumor efficacy and safety is of great interest. Here, we report on CD44-targeting GEM nanotherapeutics obtained by encapsulating hydrophobic phosphorylated GEM prodrug (HPG), a single isomer of NUC-1031, into A6 peptide-functionalized disulfide-crosslinked micelles (A6-mHPG). A6-mHPG demonstrates stability against degradation, enhanced internalization and inhibition toward CD44+ cells, and increased accumulation in A549 lung tumor xenografts, leading to potent repression of orthotopic tumor growth, depleted toxicity and marked survival benefits. The targeted delivery of GEM prodrug using A6-mHPG is a highly appealing strategy to GEM cancer therapy.


Assuntos
Antineoplásicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Pró-Fármacos , Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Desoxicitidina/análogos & derivados , Dissulfetos , Humanos , Receptores de Hialuronatos , Pulmão , Neoplasias Pulmonares/tratamento farmacológico , Metoxi-Hidroxifenilglicol , Micelas , Pró-Fármacos/química , Pró-Fármacos/farmacologia
2.
Int J Mol Sci ; 23(2)2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-35054851

RESUMO

Norepinephrine is a neurotransmitter that also has an immunomodulatory effect and is involved in multiple sclerosis (MS) pathogenesis. This study aimed to clarify the role of the ß2-adrenoreceptor in the norepinephrine-mediated modulation of interleukin-17 (IL-17) and interferon-γ (IFN-γ) production, which play a critical pathogenetic role in MS. CD4+ T cells obtained from twenty-five relapsing-remitting MS patients and sixteen healthy subjects were cultured ex vivo with norepinephrine and/or ß2-adrenoreceptor antagonist or agonist, followed by a cytokine production analysis using ELISA. Norepinephrine suppressed IL-17 and IFN-γ production by the anti-CD3/anti-CD28-microbead-stimulated CD4+ T cells in both groups. Blockade of the ß2-adrenoreceptor with the specific antagonist ICI 118.551 enhanced norepinephrine-mediated IL-17 suppression but decreased its inhibitory effect on IFN-γ production in MS patients. In contrast, the ß2-adrenoreceptor agonist formoterol did not influence norepinephrine's inhibitory effect on cytokine production in both groups. The blockade of the ß2-adrenoreceptor, even in the absence of exogenous norepinephrine, suppressed IL-17 production but did not influence IFN-γ production in both groups. Conversely, ß2-adrenoreceptor activation by formoterol decreased IFN-γ production and did not affect IL-17 production in both groups. These data illustrate the inhibitory effect of norepinephrine on IL-17 and IFN-γ production by CD4+ T cells in MS. The inhibitory effect of norepinephrine on IFN-γ production by CD4+ T cells in MS could be mediated via ß2-adrenoreceptor activation.


Assuntos
Interferon gama/biossíntese , Interleucina-17/biossíntese , Esclerose Múltipla/imunologia , Receptores Adrenérgicos beta 2/metabolismo , Linfócitos T/imunologia , Adulto , Linfócitos T CD4-Positivos/imunologia , Estudos de Casos e Controles , Citocinas/metabolismo , Epinefrina/sangue , Feminino , Humanos , Masculino , Metoxi-Hidroxifenilglicol , Esclerose Múltipla/sangue , Norepinefrina/sangue
3.
Psychoneuroendocrinology ; 136: 105598, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34894424

RESUMO

Anxiety and depression are linked to both explicit and implicit memory biases, which are defined as the tendency to preferentially recall emotionally negative information at conscious and subconscious levels, respectively. Functional connectivity (FC) of the basolateral amygdala (BLA) and related stress hormones (i.e., cortisol and norepinephrine) are purportedly implicated in these biases. However, previous findings on memory biases in anxiety and depression have been inconsistent, likely due to their symptomatic complications. Therefore, the underlying neurobiological mechanism remains unclear. We thus investigated whether anxiety and depression as premorbid predispositions are related to the memory biases, and whether FC of BLA, cortisol, and 3-methoxy-4-hydroxyphenylglycol (MHPG: a major metabolite of norepinephrine) would affect the anxiety/depression-related biased memory recall in 100 participants without psychiatric symptomatology. Psycho-behavioral assessment, resting-state fMRI scans, and saliva collection at 10-points-in-time across two days were conducted. Correlations of memory biases with anxiety/depression and neurobiological markers were explored. As a result, neither anxiety nor depression were correlated with explicit memory bias to negative (vs. positive) information, although depression was associated with better recall of the negative stimuli only when they were perceived as self-relevant. In contrast, both anxiety and depression were correlated with implicit memory bias; however, the effects were solely explained by anxiety. Furthermore, FC of the BLA with subgenual anterior cingulate cortex (sgACC) and the synergetic effect of cortisol and MHPG uniquely affected the implicit memory bias. These findings suggest that anxiety facilitates an initial snapshot of negative information and can be accompanied by depression when the information creates negative semantic associations with the self. The BLA-sgACC neural connectivity and cortisol-norepinephrine interaction that are associated with the implicit memory bias might be one of the important neurobiological targets in the prevention and treatment for comorbid anxiety and depressive disorders.


Assuntos
Complexo Nuclear Basolateral da Amígdala , Hidrocortisona , Ansiedade , Depressão , Humanos , Imageamento por Ressonância Magnética , Metoxi-Hidroxifenilglicol , Norepinefrina
4.
Cell Rep ; 37(9): 110076, 2021 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-34852231

RESUMO

A core network of widely expressed proteins within the glutamatergic post-synapse mediates activity-dependent synaptic plasticity throughout the brain, but the specific proteomic composition of synapses differs between brain regions. Here, we address the question, how does proteomic composition affect activity-dependent protein-protein interaction networks (PINs) downstream of synaptic activity? Using quantitative multiplex co-immunoprecipitation, we compare the PIN response of in vivo or ex vivo neurons derived from different brain regions to activation by different agonists or different forms of eyeblink conditioning. We report that PINs discriminate between incoming stimuli using differential kinetics of overlapping and non-overlapping PIN parameters. Further, these "molecular logic rules" differ by brain region. We conclude that although the PIN of the glutamatergic post-synapse is expressed widely throughout the brain, its activity-dependent dynamics show remarkable stimulus-specific and brain-region-specific diversity. This diversity may help explain the challenges in developing molecule-specific drug therapies for neurological disorders.


Assuntos
Piscadela/efeitos dos fármacos , Encéfalo/metabolismo , Metoxi-Hidroxifenilglicol/análogos & derivados , N-Metilaspartato/farmacologia , Mapas de Interação de Proteínas , Proteoma/metabolismo , Sinapses/metabolismo , Animais , Encéfalo/efeitos dos fármacos , Condicionamento Palpebral , Agonistas de Aminoácidos Excitatórios/farmacologia , Feminino , Masculino , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos , Plasticidade Neuronal , Proteoma/análise , Sinapses/efeitos dos fármacos
5.
Neurobiol Dis ; 159: 105466, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34390832

RESUMO

Group I metabotropic glutamate receptors (mGluRs), mGluR1 and mGluR5, in the spinal cord are implicated in nociceptive transmission and plasticity through G protein-mediated second messenger cascades leading to the activation of various protein kinases such as extracellular signal-regulated kinase (ERK). In this study, we demonstrated that cytohesin-2, a guanine nucleotide exchange factor for ADP ribosylation factors (Arfs), is abundantly expressed in subsets of excitatory interneurons and projection neurons in the superficial dorsal horn. Cytohesin-2 is enriched in the perisynapse on the postsynaptic membrane of dorsal horn neurons and forms a protein complex with mGluR5 in the spinal cord. Central nervous system-specific cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia in inflammatory and neuropathic pain models. Pharmacological blockade of cytohesin catalytic activity with SecinH3 similarly reduced mechanical allodynia and inhibited the spinal activation of Arf6, but not Arf1, in both pain models. Furthermore, cytohesin-2 conditional knockout mice exhibited reduced mechanical allodynia and ERK1/2 activation following the pharmacological activation of spinal mGluR1/5 with 3,5-dihydroxylphenylglycine (DHPG). The present study suggests that cytothesin-2 is functionally associated with mGluR5 during the development of mechanical allodynia through the activation of Arf6 in spinal dorsal horn neurons.


Assuntos
/metabolismo , Proteínas Ativadoras de GTPase/genética , Hiperalgesia/genética , Neuralgia/genética , Células do Corno Posterior/metabolismo , Receptor de Glutamato Metabotrópico 5/metabolismo , Medula Espinal/metabolismo , Fator 1 de Ribosilação do ADP/efeitos dos fármacos , Fator 1 de Ribosilação do ADP/metabolismo , Animais , Proteínas Ativadoras de GTPase/antagonistas & inibidores , Proteínas Ativadoras de GTPase/metabolismo , Hiperalgesia/metabolismo , Inflamação/genética , Inflamação/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/genética , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos , Camundongos Knockout , Neuralgia/metabolismo , Densidade Pós-Sináptica/metabolismo , Células do Corno Posterior/efeitos dos fármacos , Receptor de Glutamato Metabotrópico 5/agonistas , Receptores de Glutamato Metabotrópico/agonistas , Medula Espinal/efeitos dos fármacos , Corno Dorsal da Medula Espinal , Triazóis/farmacologia
6.
Sci Rep ; 11(1): 16276, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381165

RESUMO

Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder. Traumatic stress during adolescence increases the risk of IBS in adults. The aim of this study was to characterize the juvenile social defeat stress (SDS)-associated IBS model in mice. Juvenile mice were exposed to an aggressor mouse for 10 min once daily for 10 consecutive days. Behavioral tests, visceral sensitivity, immune responses, and fecal bacteria in the colon were evaluated in 5 weeks after SDS exposure. Social avoidance, anxiety- and depression-like behavior, and visceral hypersensitivity were observed. Juvenile SDS exposure significantly increased the number of 5-HT-containing cells and calcitonin gene-related peptide-positive neurons in the colon. The gut microbiota was largely similar between the control and juvenile SDS groups. The alterations in fecal pellet output, bead expulsion time, plasma corticosterone concentration, and colonic 5-HT content in response to restraint stress were exacerbated in the juvenile SDS group compared with the control group. The combination of juvenile SDS and restraint stress increased the noradrenaline metabolite 3-Methoxy-4-hydroxyphenylglycol (MHPG) content and MHPG/noradrenaline ratio in the amygdala when compared with restraint stress in control mice. These results suggest that juvenile SDS exposure results in later onset of IBS-like symptoms.


Assuntos
Síndrome do Intestino Irritável/etiologia , Síndrome do Intestino Irritável/psicologia , Derrota Social , Estresse Psicológico/complicações , Estresse Psicológico/psicologia , Dor Abdominal , Fatores Etários , Animais , Ansiedade , Aprendizagem da Esquiva , Comportamento Animal , Colo/metabolismo , Modelos Animais de Doenças , Síndrome do Intestino Irritável/metabolismo , Masculino , Metoxi-Hidroxifenilglicol/metabolismo , Camundongos , Norepinefrina/metabolismo , Serotonina/metabolismo , Comportamento Social , Estresse Psicológico/etiologia , Estresse Psicológico/metabolismo
7.
J Neurosci ; 41(35): 7340-7349, 2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34290083

RESUMO

Alzheimer's disease (AD) is a progressive neurodegenerative disease marked by the accumulation of amyloid-ß (Aß) plaques and neurofibrillary tangles. Aß oligomers cause synaptic dysfunction early in AD by enhancing long-term depression (LTD; a paradigm for forgetfulness) via metabotropic glutamate receptor (mGluR)-dependent regulation of striatal-enriched tyrosine phosphatase (STEP61). Reelin is a neuromodulator that signals through ApoE (apolipoprotein E) receptors to protect the synapse against Aß toxicity (Durakoglugil et al., 2009) Reelin signaling is impaired by ApoE4, the most important genetic risk factor for AD, and Aß-oligomers activate metabotropic glutamate receptors (Renner et al., 2010). We therefore asked whether Reelin might also affect mGluR-LTD. To this end, we induced chemical mGluR-LTD using DHPG (Dihydroxyphenylglycine), a selective mGluR5 agonist. We found that exogenous Reelin reduces the DHPG-induced increase in STEP61, prevents the dephosphorylation of GluA2, and concomitantly blocks mGluR-mediated LTD. By contrast, Reelin deficiency increased expression of Ca2+-permeable GluA2-lacking AMPA receptors along with higher STEP61 levels, resulting in occlusion of DHPG-induced LTD in hippocampal CA1 neurons. We propose a model in which Reelin modulates local protein synthesis as well as AMPA receptor subunit composition through modulation of mGluR-mediated signaling with implications for memory consolidation or neurodegeneration.SIGNIFICANCE STATEMENT Reelin is an important neuromodulator, which in the adult brain controls synaptic plasticity and protects against neurodegeneration. Amyloid-ß has been shown to use mGluRs to induce synaptic depression through endocytosis of NMDA and AMPA receptors, a mechanism referred to as LTD, a paradigm of forgetfulness. Our results show that Reelin regulates the phosphatase STEP, which plays an important role in neurodegeneration, as well as the expression of calcium-permeable AMPA receptors, which play a role in memory formation. These data suggest that Reelin uses mGluR LTD pathways to regulate memory formation as well as neurodegeneration.


Assuntos
Depressão Sináptica de Longo Prazo/fisiologia , Neurônios/fisiologia , Proteínas Tirosina Fosfatases não Receptoras/fisiologia , Receptores de Glutamato Metabotrópico/fisiologia , /fisiologia , 2-Amino-5-fosfonovalerato/farmacologia , Animais , Região CA1 Hipocampal/citologia , Região CA1 Hipocampal/efeitos dos fármacos , Cálcio/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Indução Enzimática/efeitos dos fármacos , Depressão Sináptica de Longo Prazo/efeitos dos fármacos , Memória/fisiologia , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos , Degeneração Neural/fisiopatologia , Neurônios/efeitos dos fármacos , Técnicas de Patch-Clamp , Fosforilação/efeitos dos fármacos , Picrotoxina/farmacologia , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Receptores de AMPA/metabolismo , Receptores de Glutamato Metabotrópico/agonistas , Proteínas Recombinantes/metabolismo , /genética
8.
Asian J Psychiatr ; 62: 102711, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34090249

RESUMO

AIM: The purpose of this meta-analysis was to critically examine the data from individual studies on CSF neurotransmitter metabolites to see whether there were consistencies in the results of the comparison of suicide attempters and psychiatric controls and of the comparison of attempted suicides using violent versus nonviolent methods. METHOD: Systematic literature search across different electronic databases using PubMed/Google Scholar/EMBASE/Cochrane library was conducted for studies that reported concentration of CSF-neurotransmitter metabolites: 5-hydroxyindoleacetic acid (5-HIAA), homovanillic acid (HVA) and 3-methoxy-4-hydroxy phenylglycol (MHPG) in suicide attempters, from January'1981 to November'2020. Standardized mean differences (SMDs) and corresponding 95 % confidence interval (CIs) were deduced for outcome measures. I2 statistics were used to assess heterogeneity within studies. Data were analyzed using STATA software. RESULTS: A total of 36 studies (N = 1987 attempted suicide and N = 1235 psychiatry control) were included for the meta-analysis. We found CSF levels of all the 3 metabolites i.e. 5-HIAA (SMD= -0.43; 95 %CI: -0.61, -0.24), HVA (SMD= -0.16; 95 %CI: -0.33, -0.00) and MHPG (SMD= -0.33; 95 %CI: -0.71, -0.05) were lower in suicide attempters. While the findings were consistent for 5-HIAA, they were inconsistent for the HVA and MHPG. CSF levels of 5-HIAA (SMD= -0.66; 95 %; CI: -1.01, -0.31), HVA (SMD= -0.14; 95 %CI: -0.45, 0.16) and MHPG (SMD= -0.12; 95 %CI: -0.56, 0.31) were significantly lower in violent suicide attempters than non-violent attempters. No significant publication bias found in any study. CONCLUSION: We found a significant association between lower levels of CSF 5-HIAA in suicide attempters, particularly the violent ones, compared to psychiatric controls, whereas findings from CSF HVA and MHPG were inconsistent.


Assuntos
Metoxi-Hidroxifenilglicol , Tentativa de Suicídio , Agressão , Ácido Homovanílico , Humanos , Ácido Hidroxi-Indolacético
9.
Reprod Domest Anim ; 56(7): 1004-1014, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33908088

RESUMO

Supplementing the extender with antioxidants with low molecular weight can enhance the quality of the post-thaw sperm during the freezing process. This study was aimed at determining the impacts of 3,4-dihydroxyphenyl glycol (DHPG) on the spermatozoa of the canine undergoing freeze-thawing process. In this study, 24 ejaculates were obtained from three mixed-breed dogs and were diluted in a Tris-based extender. The diluted semen was divided into aliquots for supplementation of 10, 30, 50 and 70 µg/ml of DHPG, control (without antioxidant) and control sham (DMSO). After being extended, the semen was equilibrated at a temperature of 4°C and then transferred to the straws and kept 4 cm above the liquid nitrogen for 20 min and was finally immersed in the liquid nitrogen. They were cryopreserved for seven days; then, sperm parameters including sperm motility evaluation, motility characteristics, viability, DNA and plasma membrane integrity, total antioxidant capacity (TAC), reduced glutathione content (GSH), antioxidant enzymes (superoxide dismutase [SOD], catalase [CAT] and glutathione peroxidase [GPx]) activity malondialdehyde (MDA) levels were evaluated. This study showed that spermatozoa cryopreservation with 50, 30 and 70 µg/ml of DHPG concentrations had better progressive motility, Curvilinear Velocity, Linearity, viability, intact plasma membrane and the levels of TAC, GPx and GSH were higher than the control group. The 50, 30 and 70 µg/ml of DHPG concentrations led to the significant decrease of DNA damage compared to the control group. Total motility, average path velocity, straight-line velocity and CAT activity were significantly improved in 30 and 50 µg/ml of DHPG concentrations, compared to the control group. Also, the 50 and 30 µg/ml of DHPG concentrations, decreased MDA levels compared to the other groups, significantly. In conclusion, our study showed that the addition 50 µg/ml of DHPG to the canine semen extender improved the semen characteristics and oxidative markers in the cryopreservation process.


Assuntos
Criopreservação/veterinária , Crioprotetores/farmacologia , Cães , Metoxi-Hidroxifenilglicol/farmacologia , Animais , Antioxidantes , Criopreservação/métodos , Dano ao DNA , Congelamento , Masculino , Análise do Sêmen/veterinária , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade Espermática/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos
10.
J Neurochem ; 158(2): 554-568, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33894018

RESUMO

The synucleinopathies Parkinson's disease (PD), multiple system atrophy (MSA), and pure autonomic failure (PAF) are characterized by intra-cytoplasmic deposition of the protein alpha-synuclein and by catecholamine depletion. PAF, which manifests with neurogenic orthostatic hypotension (nOH) and no motor signs of central neurodegeneration, can evolve into PD+nOH. The cerebrospinal fluid (CSF) levels of catecholamine metabolites may indicate central catecholamine deficiency in these synucleinopathies, but the literature is inconsistent and incomplete. In this retrospective cohort study we reviewed data about CSF catecholamines, the dopamine metabolites 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA), and the norepinephrine metabolites 3,4-dihydroxyphenylglycol (DHPG) and 3-methoxy-4-hydroxyphenylglycol (MHPG). The compounds were measured in 36 patients with PD, 37 patients with MSA, and 19 patients with PAF and in 38 controls. Compared to the control group, the PD, MSA, and PAF groups had decreased CSF MHPG (p < .0001 each by Dunnett's post hoc test), DHPG (p = .004; p < .0001; p < .0001) and norepinephrine (p = .017; p = .0003; p = .044). CSF HVA and DOPAC were decreased in PD (p < .0001 each) and MSA (p < .0001 each) but not in PAF. The three synucleinopathies therefore have in common in vivo evidence of central noradrenergic deficiency but differ in the extents of central dopaminergic deficiency-prominent in PD and MSA, less apparent in PAF. Data from putamen 18 F-DOPA and cardiac 18 F-dopamine neuroimaging in the same patients, post-mortem tissue catecholamines in largely separate cohorts, and review of the neuropathology literature fit with these distinctions. The results suggest a 'norepinephrine first' ascending pathogenetic sequence in synucleinopathies, with degeneration of pontine locus ceruleus noradrenergic neurons preceding the loss of midbrain substantia nigra dopaminergic neurons.


Assuntos
Dopamina/líquido cefalorraquidiano , Norepinefrina/líquido cefalorraquidiano , Sinucleinopatias/líquido cefalorraquidiano , Ácido 3,4-Di-Hidroxifenilacético/líquido cefalorraquidiano , Idoso , Estudos de Coortes , Neurônios Dopaminérgicos/patologia , Feminino , Ácido Homovanílico/líquido cefalorraquidiano , Humanos , Masculino , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano , Pessoa de Meia-Idade , Atrofia de Múltiplos Sistemas/líquido cefalorraquidiano , Atrofia de Múltiplos Sistemas/patologia , Neurônios/patologia , Doença de Parkinson/líquido cefalorraquidiano , Doença de Parkinson/patologia , Insuficiência Autonômica Pura/líquido cefalorraquidiano , Insuficiência Autonômica Pura/patologia , Estudos Retrospectivos , Sinucleinopatias/patologia
11.
Neurobiol Aging ; 102: 17-22, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33667876

RESUMO

Advanced Alzheimer's disease (AD) is characterized by higher noradrenaline metabolite levels that may be associated with AD pathology. The locus coeruleus (LC) is the main site for cerebral noradrenaline synthesis and LC volume loss occurs as early as Braak stage 1. This study investigates the association between noradrenergic turnover and brain morphology, and the modifying effect of AD pathology. The study sample included 77 memory clinic patients (37 cognitively unimpaired and 40 cognitively impaired (mild cognitive impairment or AD dementia)). Cortical thickness and volumetric analyses were performed using FreeSurfer. Cerebrospinal fluid was analyzed for noradrenergic metabolite 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG), Aß42 and phosphorylated tau. Higher MHPG was associated with lower cortical thickness and hippocampal volume at lower, but subthreshold, levels of Aß42 and at higher p-tau levels. These associations remained significant after adding APOE-E4 or cognitive status as covariates. Our results suggest that greater MHPG together with worse AD pathology contributes to neurodegeneration, possibly before significant amyloidosis. The noradrenergic system may play an important role in early detection of AD-related processes.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Córtex Cerebral/patologia , Locus Cerúleo/metabolismo , Locus Cerúleo/patologia , Norepinefrina/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/etiologia , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Cognição , Feminino , Humanos , Masculino , Metoxi-Hidroxifenilglicol/líquido cefalorraquidiano , Pessoa de Meia-Idade , Degeneração Neural , Tamanho do Órgão , Fragmentos de Peptídeos/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
12.
Clin Auton Res ; 31(3): 395-403, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33782836

RESUMO

PURPOSE: Ampreloxetine is a novel, selective, long-acting norepinephrine reuptake (NET) inhibitor being investigated as a once-daily oral treatment for symptomatic neurogenic orthostatic hypotension (nOH) in patients with autonomic synucleinopathies. The purpose of this study was to characterize the pharmacokinetic and pharmacodynamic profiles of ampreloxetine in this target population. METHODS: Patients with nOH were enrolled in a multicenter, phase II clinical trial of ampreloxetine (NCT02705755). They received escalating doses over 5 days in the clinical research unit, followed by 20 weeks of open-label treatment and then a 4-week withdrawal. As neurochemical biomarkers of NET inhibition, we assayed plasma concentrations of norepinephrine (NE) and its main intraneuronal metabolite 3,4-dihydroxyphenylglycol (DHPG) pre- and post-ampreloxetine. RESULTS: Thirty-four patients with nOH were enrolled. Plasma ampreloxetine concentrations increased with repeated escalating doses, with peak concentrations observed 6-9 h post-drug administration. The median ampreloxetine dose in the 20-week treatment phase was 10 mg once daily. Plasma ampreloxetine concentrations reached steady state by 2 weeks, with stable plasma levels over 24 h. No influence of age or renal function on ampreloxetine plasma concentrations was observed. On treatment, compared to baseline, plasma NE significantly increased by 71% (p < 0.005), plasma DHPG significantly declined by 22% (p < 0.05), and the NE:DHPG ratio significantly increased (p < 0.001). CONCLUSIONS: Persistent elevation of plasma NE levels accompanied by reduced DHPG levels after ampreloxetine suggests reduced neuronal reuptake and metabolism of NE in postganglionic efferent sympathetic neurons. The findings are consistent with long-lasting NET inhibition, which may increase vasoconstrictor tone, supporting once-daily ampreloxetine dosing in patients with nOH.


Assuntos
Hipotensão Ortostática , Sistema Nervoso Autônomo , Humanos , Hipotensão Ortostática/tratamento farmacológico , Metoxi-Hidroxifenilglicol , Norepinefrina
13.
J Alzheimers Dis ; 80(2): 521-526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33554915

RESUMO

The noradrenergic (NE) locus coeruleus (LC) is vulnerable to hyperphosphorylated tau, and dysregulated NE-metabolism is linked to greater tau and disease progression. We investigated whether elevated NE-metabolism alone predicts memory decline or whether concomitant presence of tau and amyloid-ß is required. Among 114 memory clinic participants, time trends (max. six years) showed dose-response declines in learning across groups with elevated NE-metabolite 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) with no, one, or two Alzheimer's disease biomarkers; and no decline in the low MHPG group. Elevated MHPG is required and sufficient to detect learning declines, supporting a pathophysiologic model including the LC-NE system contributing to initial Alzheimer's disease-related processes.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/psicologia , Transtornos da Memória/psicologia , Norepinefrina/metabolismo , Idoso , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Disfunção Cognitiva/patologia , Disfunção Cognitiva/psicologia , Estudos de Coortes , Progressão da Doença , Feminino , Humanos , Aprendizagem , Locus Cerúleo/metabolismo , Masculino , Transtornos da Memória/patologia , Metoxi-Hidroxifenilglicol/metabolismo , Pessoa de Meia-Idade , Testes Neuropsicológicos , Norepinefrina/líquido cefalorraquidiano , Valor Preditivo dos Testes , Proteínas tau/genética , Proteínas tau/metabolismo
14.
Neurotox Res ; 39(3): 634-644, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33464538

RESUMO

Aluminum demonstrates clear neurotoxicity and can cause Alzheimer's disease (AD)-like symptoms, including cognitive impairment. One toxic effect of aluminum is a decrease in synaptic plasticity, but the specific mechanism remains unclear. In this study, PC12 cells were treated with Al(mal)3 to construct a toxic cell model. (S)-3,5-Dihydroxyphenylglycine (DHPG), α-methyl-4-carboxyphenylglycine (MCPG), and mGluR1-siRNA were used to interfere with the expression of metabotropic glutamate receptor subtype 1 (mGluR1). Polymerase chain reaction and western blotting were used to investigate the expression of mGluR1, protein kinase C (PKC), and N-methyl-D-aspartate receptor (NMDAR) subunits. ELISA was used to detect PKC enzyme activity. In PC12 cells, mRNA and protein expressions of PKC and NMDAR subunits were inhibited by Al(mal)3. Aluminum may further regulate the expression of NMDAR1 and NMDAR2B through mGluR1 to regulate PKC enzyme activity, thereby affecting learning and memory functions. Furthermore, the results implied that the mGluR1-PKC-NMDAR signaling pathway may predominately involve positive regulation. These findings provide new targets for studying the neurotoxic mechanism of aluminum.


Assuntos
Alumínio/toxicidade , Proteína Quinase C/biossíntese , Receptores de Glutamato Metabotrópico/biossíntese , Receptores de N-Metil-D-Aspartato/biossíntese , Animais , Expressão Gênica , Glicina/análogos & derivados , Glicina/farmacologia , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Células PC12 , Ratos , Receptores de Glutamato Metabotrópico/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
15.
Mol Autism ; 11(1): 78, 2020 10 14.
Artigo em Inglês | MEDLINE | ID: mdl-33054857

RESUMO

BACKGROUND: Mutations in TSC2 are the most common cause of tuberous sclerosis (TSC), a disorder with a high incidence of autism and intellectual disability. TSC2 regulates mRNA translation required for group 1 metabotropic glutamate receptor-dependent synaptic long-term depression (mGluR-LTD) and behavior, but the identity of mRNAs responsive to mGluR-LTD signaling is largely unknown. METHODS: We utilized Tsc2+/- mice as a mouse model of TSC and prepared hippocampal slices from these animals. We induced mGluR-LTD synaptic plasticity in slices and processed the samples for RNA-seq and ribosome profiling to identify differentially expressed genes in Tsc2+/- and following mGluR-LTD synaptic plasticity. RESULTS: Ribosome profiling reveals that in Tsc2+/- mouse hippocampal slices, the expression of several mRNAs was dysregulated: terminal oligopyrimidine (TOP)-containing mRNAs decreased, while FMRP-binding targets increased. Remarkably, we observed the opposite changes of FMRP binding targets in Fmr1-/y hippocampi. In wild-type hippocampus, induction of mGluR-LTD caused rapid changes in the steady-state levels of hundreds of mRNAs, many of which are FMRP targets. Moreover, mGluR-LTD failed to promote phosphorylation of eukaryotic elongation factor 2 (eEF2) in TSC mice, and chemically mimicking phospho-eEF2 with low cycloheximide enhances mGluR-LTD in TSC mice. CONCLUSION: These results suggest a molecular basis for bidirectional regulation of synaptic plasticity and behavior by TSC2 and FMRP. Our study also suggests that altered mGluR-regulated translation elongation contributes to impaired synaptic plasticity in Tsc2+/- mice.


Assuntos
Proteína do X Frágil de Retardo Mental/metabolismo , Hipocampo/metabolismo , Plasticidade Neuronal , Ribossomos/metabolismo , Proteína 2 do Complexo Esclerose Tuberosa/metabolismo , Animais , Síndrome do Cromossomo X Frágil/patologia , Síndrome do Cromossomo X Frágil/fisiopatologia , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos Endogâmicos C57BL , Fator 2 de Elongação de Peptídeos/metabolismo , Ligação Proteica , Biossíntese de Proteínas , Sequência de Oligopirimidina na Região 5' Terminal do RNA/genética , Receptores de Glutamato Metabotrópico/metabolismo , Transdução de Sinais/efeitos dos fármacos
16.
Mol Cell Proteomics ; 19(12): 1952-1968, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32912969

RESUMO

At neuronal synapses, activation of group I metabotropic glutamate receptors (mGluR1/5) triggers a form of long-term depression (mGluR-LTD) that relies on new protein synthesis and the internalization of AMPA-type glutamate receptors. Dysregulation of these processes has been implicated in the development of mental disorders such as autism spectrum disorders and therefore merit a better understanding on a molecular level. Here, to study mGluR-induced signaling pathways, we integrated quantitative phosphoproteomics with the analyses of newly synthesized proteins via bio-orthogonal amino acids (azidohomoalanine) in a pulsed labeling strategy in cultured hippocampal neurons stimulated with DHPG, a specific agonist for group I mGluRs. We identified several kinases with important roles in DHPG-induced mGluR activation, which we confirmed using small molecule kinase inhibitors. Furthermore, changes in the AMPA receptor endocytosis pathway in both protein synthesis and protein phosphorylation were identified, whereby Intersectin-1 was validated as a novel player in this pathway. This study revealed several new insights into the molecular pathways downstream of group I mGluR activation in hippocampal neurons, and provides a rich resource for further analyses.


Assuntos
Neurônios/metabolismo , Biossíntese de Proteínas , Proteômica , Receptores de Glutamato Metabotrópico/metabolismo , Sequência de Aminoácidos , Animais , Endocitose/efeitos dos fármacos , Hipocampo/metabolismo , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Neurônios/efeitos dos fármacos , Fosforilação/efeitos dos fármacos , Biossíntese de Proteínas/efeitos dos fármacos , Ratos , Receptores de AMPA/metabolismo , Receptores de Glutamato Metabotrópico/química , Transdução de Sinais/efeitos dos fármacos , Fatores de Tempo
17.
Biochem Biophys Res Commun ; 531(3): 383-389, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32800547

RESUMO

Tumor necrosis factor-alpha (TNF-α), a major inflammatory factor released from activated retinal glial cells, is implicated in the pathogenesis of glaucoma. In this study, we investigated whether and how TNF-α may affect functional conditions of activated retinal Müller cells. Our results showed that in the group I metabotropic glutamate receptor (mGluR I) agonist DHPG-activated cultured Müller cells, TNF-α treatment aggravated cell gliosis, as evidenced by significantly increased expression of glial fibrillary acidic protein (GFAP). TNF-α treatment of the DHPG-activated Müller cells decreased cell proliferation and induced cell apoptosis. In normal Müller cells, TNF-α treatment increased the mRNA levels of leukocyte inhibitory factor (LIF), intercellular cell adhesion molecule (ICAM), vascular cell adhesion molecule (VCAM), and chemokine C-C-motif ligand 2 (CCL2), which could be significantly attenuated when Müller cells were pre-activated. However, TNF-α-induced elevation in mRNA levels of inflammatory factors, such as TNF-α, inducible nitric oxide synthase (iNOS), and interleukin-6 (IL-6), in normal Müller cells still kept higher levels when Müller cells were pre-activated. Furthermore, the TNF-α-induced changes of cytokines were partially mediated by NF-κB signaling pathway. Our results suggest that TNF-α may promote gliosis and inflammatory response of activated Müller cells, thus aggravating RGC injury in glaucoma.


Assuntos
Células Ependimogliais/patologia , Gliose/patologia , Inflamação/patologia , Fator de Necrose Tumoral alfa/toxicidade , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citocinas/metabolismo , Células Ependimogliais/efeitos dos fármacos , Células Ependimogliais/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Gliose/complicações , Inflamação/complicações , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos
18.
Learn Mem ; 27(9): 380-389, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32817304

RESUMO

Cannabinoid receptors are widely expressed throughout the hippocampal formation, but are particularly dense in the dentate gyrus (DG) subregion. We, and others, have shown in mice that cannabinoid type 1 receptors (CB1Rs) are involved in a long-term depression (LTD) that can be induced by prolonged 10 Hz stimulation of the medial perforant path (MPP)-granule cell synaptic input to the DG. Here, we extend this work to examine the involvement of CB1Rs in other common forms of LTD in the hippocampus of juvenile male and female Sprague-Dawley rats (Rattus norvegicus). We found, as in mice, that prolonged 10 Hz stimulation (6000 pulses) could reliably induce a form of LTD that was dependent upon CB1R activation. In addition, we also discovered a role for both CB1R and mGluR proteins in LTD induced with 1 Hz low-frequency stimulation (1 Hz-LTD; 900 pulses) and in LTD induced by bath application of the group I mGluR agonist (RS)-3,5-Dihydroxyphenylglycine (DHPG; DHPG-LTD). This study elucidates an essential role for endocannabinoid receptors in a number of forms of LTD in the rat DG, and identifies a novel role for CB1Rs as potential therapeutic targets for conditions that involve impaired LTD in the DG.


Assuntos
Giro Denteado/metabolismo , Depressão Sináptica de Longo Prazo/fisiologia , Receptor CB1 de Canabinoide/fisiologia , Animais , Estimulação Elétrica , Feminino , Masculino , Metoxi-Hidroxifenilglicol/análogos & derivados , Metoxi-Hidroxifenilglicol/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de Glutamato Metabotrópico/agonistas
19.
PLoS One ; 15(5): e0232233, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32365077

RESUMO

The physiological actions of orally ingested peptides on the brain remain poorly understood. This study examined the effects of 39 orally administered synthetic Tyr-containing dipeptides on the enhancement of brain norepinephrine metabolism in mice by comparing the concentration of 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG). Although Tyr-Tyr administration increased blood and cerebral cortex (Cx) Tyr concentrations the most, Tyr-Trp increased Cx MHPG concentration the most. The oral administration of Tyr-Trp ameliorated a short-term memory deficit of a mouse model of cognitive dysfunction induced by amyloid beta peptide 25-35. Gene expression profiling of mouse brain using a microarray indicated that Tyr-Trp administration led to a wide variety of changes in mRNA levels, including the upregulation of genes encoding molecules involved in catecholamine metabolism. A comparative metabolome analysis of the Cx of mice given Tyr-Trp or Tyr-Tyr demonstrated that Tyr-Trp administration yielded higher concentrations of Trp and kynurenine pathway metabolites than Tyr-Tyr administration, as well as higher L-dopa levels, which is the initial product of catecholamine metabolism. Catecholamines were not significantly increased in the Cx of the Tyr-Tyr group compared with the Tyr-Trp group, despite a marked increase in Tyr. Presumably, Tyr-Trp administration enhances catecholamine synthesis and metabolism via the upregulation of genes involved in Tyr and Trp metabolism as well as metabolites of Tyr and Trp. These findings strongly suggest that orally ingested Tyr-Trp modulates the brain metabolome involved in catecholamine metabolism and contributes to higher brain function.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Dipeptídeos/administração & dosagem , Memória de Curto Prazo/efeitos dos fármacos , Metoxi-Hidroxifenilglicol/análise , Administração Oral , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/genética , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/efeitos adversos , Animais , Catecolaminas/biossíntese , Córtex Cerebral/química , Córtex Cerebral/efeitos dos fármacos , Dipeptídeos/farmacologia , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Redes Reguladoras de Genes/efeitos dos fármacos , Humanos , Masculino , Metaboloma/efeitos dos fármacos , Camundongos , Fragmentos de Peptídeos/efeitos adversos
20.
Biochem Pharmacol ; 177: 114011, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32380090

RESUMO

Allosteric modulators of metabotropic glutamate receptor subtype 5 (mGlu5) represent an attractive therapeutic strategy for multiple CNS disorders. Chemically distinct mGlu5 positive allosteric modulators (PAMs) that interact with a common binding site can demonstrate biased allosteric agonism relative to the orthosteric agonist, DHPG, when comparing activity in signaling assays such as IP1 accumulation, ERK1/2 phosphorylation (pERK1/2) and iCa2+ mobilization. However, the structural basis for such biased agonism is not well understood. Therefore, we evaluated biased allosteric agonism mediated by four mGlu5 PAM-agonists from diverse chemical scaffolds (i.e., DPFE, VU0409551, VU29, and VU0424465) for three measures of mGlu5 activation (i.e., iCa2+ mobilization, IP1 accumulation and ERK1/2 phosphorylation) at eight single-point mutations within the common allosteric binding pocket of mGlu5. In particular, mGlu5 allosteric site mutations had differential effects on the intrinsic efficacy of mGlu5 PAMs for multiple signaling pathways. Specifically, a loss of agonism for iCa2+ mobilization was evident for DPFE and VU0409551 for most mutants, whereas IP1 accumulation and ERK phosphorylation were retained, albeit with reduced maximal responses. Additionally, bias profiles between iCa2+ mobilization and IP1/ERK pathways remained similar to wild type for most mutants. However, W784A and A809G mutants lost bias between IP1 accumulation and ERK phosphorylation for VU0424465, whereas a loss of bias between iCa2+ mobilization and ERK1/2 phosphorylation was evident for F787A, S808A and A809G mutants. These data provide further insight into the structural requirements for allosteric agonism across multiple mGlu5-mediated signaling pathways. An understanding of mGlu5 biased agonism at a structural level may provide the foundation for rational structure-based design of biased allosteric ligands for the treatment of neurological disorders.


Assuntos
Metoxi-Hidroxifenilglicol/análogos & derivados , Niacinamida/análogos & derivados , Oxazóis/farmacologia , Piperazinas/farmacologia , Piridinas/farmacologia , Receptor de Glutamato Metabotrópico 5/agonistas , Receptor de Glutamato Metabotrópico 5/metabolismo , Regulação Alostérica/efeitos dos fármacos , Sítio Alostérico , Animais , Sítios de Ligação , Cálcio/metabolismo , Relação Dose-Resposta a Droga , Células HEK293 , Humanos , Fosfatos de Inositol/metabolismo , Metoxi-Hidroxifenilglicol/farmacologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Mutação , Niacinamida/química , Niacinamida/farmacologia , Oxazóis/química , Fosforilação/efeitos dos fármacos , Piridinas/química , Ratos , Receptor de Glutamato Metabotrópico 5/genética
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