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1.
J Med Chem ; 64(2): 1180-1196, 2021 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-33439019

RESUMO

G-protein coupled receptors (GPCRs) exist in an equilibrium of multiple conformational states, including different active states, which depend on the nature of the bound ligand. In consequence, different conformational states can initiate specific signal transduction pathways. The study identified compound 7e, which acts as a potent 5-hydroxytryptamine type 6 receptor (5-HT6R) neutral antagonist at Gs and does not impact neurite growth (process controlled by Cdk5). MD simulations highlighted receptor conformational changes for 7e and inverse agonist PZ-1444. In cell-based assays, neutral antagonists of the 5-HT6R (7e and CPPQ), but not inverse agonists (SB-258585, intepirdine, PZ-1444), displayed glioprotective properties against 6-hydroxydopamine-induced and doxorubicin-induced cytotoxicity. These suggest that targeting the activated conformational state of the 5-HT6R with neutral antagonists implicates the protecting properties of astrocytes. Additionally, 7e prevented scopolamine-induced learning deficits in the novel object recognition test in rats. We propose 7e as a probe for further understanding of the functional outcomes of different states of the 5-HT6R.


Assuntos
Imidazóis/síntese química , Imidazóis/farmacologia , Piridinas/síntese química , Piridinas/farmacologia , Receptores de Serotonina/efeitos dos fármacos , Antagonistas da Serotonina/síntese química , Antagonistas da Serotonina/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Humanos , Deficiências da Aprendizagem/induzido quimicamente , Deficiências da Aprendizagem/prevenção & controle , Masculino , Conformação Molecular , Neuritos/efeitos dos fármacos , Neuroglia/efeitos dos fármacos , Fármacos Neuroprotetores/síntese química , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas-G/efeitos dos fármacos , Agonistas do Receptor de Serotonina/farmacologia , Relação Estrutura-Atividade
2.
J Agric Food Chem ; 69(2): 668-675, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33398984

RESUMO

A chemical study on the fruiting bodies of cultivated edible mushroom Inonotus hispidus resulted in 14 metabolites including three new hispolon congeners, named inonophenols A-B and one new lanostane triterpenoid, named inonoterpene A. These structures were identified by NMR, high-resolution electrospray ionization mass spectrometry (HRESIMS), and electronic circular dichroism (ECD) data analysis. All metabolites were assessed for neurotrophic, anti-inflammatory, and antioxidative activities. Among them, inonophenols B and C were the most active in promoting PC-12 cell neurite outgrowth at a concentration of 10 µM. The phenolic derivatives reduced NO generation by lipopolysaccharide (LPS)-induced BV-2 microglial cells by suppressing the expression of toll-like receptor-4 (TLR-4) and the nuclear factor-kappa-B (NF-κB) signaling pathway as well as the inflammatory mediators including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Moreover, the phenolics showed antioxidant effects in DPPH scavenging assay with the IC50 values of 9.82-21.43 µM. These findings showed that I. hispidus may be a new source of neurotrophic and protective agents against neurodegenerative disorders.


Assuntos
/química , Fenóis/química , Extratos Vegetais/química , Esteroides/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Espectrometria de Massas , Camundongos , NF-kappa B/genética , NF-kappa B/imunologia , Neuritos/efeitos dos fármacos , Neuritos/imunologia , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/imunologia , Células PC12 , Fenóis/farmacologia , Extratos Vegetais/farmacologia , Células RAW 264.7 , Ratos , Esteroides/farmacologia
3.
Toxicol Lett ; 338: 85-96, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33309997

RESUMO

Disruption of neurite outgrowth is a marker for neurotoxicity. Persistent organic pollutants (POPs) are potential developmental neurotoxicants. We investigated their effect on neurite outgrowth in PC12 rat pheochromocytoma cells, in absence or presence of nerve growth factor (NGF), an inducer of neuronal differentiation. Cells were exposed for 72 h to a defined mixture of POPs with chemical composition and concentrations based on blood levels in the Scandinavian population. We also evaluated perfluorooctane sulfonic acid (PFOS) alone, the most abundant compound in the POP mixture. Only higher concentrations of POP mixture reduced tetrazolium salt (MTT) conversion. High-content analysis showed a decrease in cell number, but no changes for nuclear and mitochondrial cellular health parameters. Robust glutathione levels were observed in NGF-differentiated cells. Live imaging, using the IncuCyte ZOOM platform indicated ongoing cell proliferation over time, but slower in presence of NGF. The pollutants did not inhibit neuritogenesis, but rather increased NGF-induced neurite length. PFOS induced neurite outgrowth to about 50 % of the level seen with the POP mixture. Neither the POP mixture nor PFOS affected neurite length in the absence of NGF. Our observations indicate that realistic complex mixtures of environmental pollutants can affect neuronal connectivity via NGF-induced neurite outgrowth.


Assuntos
Ácidos Alcanossulfônicos/toxicidade , Poluentes Ambientais/toxicidade , Fluorcarbonetos/toxicidade , Fator de Crescimento Neural/farmacologia , Neuritos/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Síndromes Neurotóxicas/etiologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Glutamato-Cisteína Ligase/genética , Glutamato-Cisteína Ligase/metabolismo , Glutationa/metabolismo , Neuritos/metabolismo , Neuritos/patologia , Síndromes Neurotóxicas/metabolismo , Síndromes Neurotóxicas/patologia , Células PC12 , Ratos , Fatores de Tempo
4.
Life Sci ; 267: 118952, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33383048

RESUMO

AIMS: Huntington's disease (HD) is a neurodegenerative disease that causes deficits in neurite outgrowth, which suggests that enhancement of neurite outgrowth is a potential direction by which to improve HD. Our previous publications showed that fibroblast growth factor 9 (FGF9) provides anti-apoptosis and anti-oxidative functions in striatal cell models of HD through the extracellular signal-regulated kinases (ERK) pathway, and FGF9 also stimulates cytoskeletons to enhance neurite outgrowth via nuclear factor kappa B (NF-kB) signaling. In this study, we further demonstrate the importance of the ERK pathway for the neurite outgrowth induced by FGF9 in HD striatal models. MATERIALS AND METHODS: FGF9 was treated with ERK (U0126) or NF-kB (BAY11-7082) inhibitors in STHdhQ7/Q7 and STHdhQ111/Q111 striatal knock-in cell lines to examine neurite outgrowth, cytoskeletal markers, and synaptic proteins via immunofluorescence staining and Western blotting. NF-kB activity was analyzed by NF-kB promoter reporter assay. KEY FINDINGS: Here, we show that suppression of ERK signaling significantly inhibits FGF9-induced neurite outgrowth, cytoskeletal markers, and synaptic proteins in HD striatal cells. In addition, we also show suppression of ERK signaling significantly decreases FGF9-induced NF-kB activation, whereas suppression of NF-kB does not decrease FGF9-induced ERK signaling. These results suggest that FGF9 activates ERK signaling first, stimulates NF-kB upregulation, and then enhances neurite outgrowth in HD striatal cells. SIGNIFICANCE: We elucidate the more detailed mechanisms of neurite outgrowth enhanced by FGF9 in these HD striatal cells. This study may provide insights into targeting neurite outgrowth for HD therapy.


Assuntos
Fator 9 de Crescimento de Fibroblastos/metabolismo , Fator 9 de Crescimento de Fibroblastos/farmacologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Neuritos/metabolismo , Animais , Butadienos/farmacologia , Linhagem Celular , Células Cultivadas , Corpo Estriado/metabolismo , Inibidores Enzimáticos/farmacologia , Fator 9 de Crescimento de Fibroblastos/antagonistas & inibidores , Humanos , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/metabolismo , Camundongos , Camundongos Transgênicos , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neuritos/efeitos dos fármacos , Crescimento Neuronal/fisiologia , Nitrilos/farmacologia , Proteínas Nucleares/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Transdução de Sinais , Sulfonas/farmacologia
5.
Food Chem ; 337: 127765, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799161

RESUMO

ß-Casomorphin-7 (BCM-7) is a heptapeptide dietary molecule derived from the digestion of the ß-casein of dairy and dairy products. In this review, we have covered the extensive details about BCM and its derived peptides out of the gastrointestinal and enzymatic digestion of milk and milk products, its structure and properties, and its immunological aspects related to human health among infants and adults of both genders. We have left judgment about BCM's pros and cons to the reader by describing the details in a cyclopedic perspective. In addition, a section on the possible ways to detect BCMs from their sources using proteomics, genome-based techniques, such as PCR and aptamers, and other analytical techniques equip the reader to get an idea about the details of the diagnostics available and possible applications in future. Overall, this review will provide information to the end-users of milk and milk products to enable them to make their own decisions about BCMs.


Assuntos
Endorfinas/química , Animais , Transtorno Autístico/patologia , Caseínas/química , Caseínas/metabolismo , Endorfinas/sangue , Endorfinas/farmacologia , Humanos , Imunidade Inata/efeitos dos fármacos , Leite/química , Leite/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Fragmentos de Peptídeos/sangue , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/farmacologia , Linfócitos T/citologia , Linfócitos T/efeitos dos fármacos , Linfócitos T/metabolismo
6.
PLoS One ; 15(8): e0237025, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32797057

RESUMO

Troxerutin (TRX) is a water-soluble flavonoid which occurs commonly in the edible plants. Recent studies state that TRX improves the functionality of the nervous system and neutralizes Amyloid-ß induced neuronal toxicity. In this study, an in vitro assay based upon Neural stem cell (NSCs) isolated from the subventricular zone of the postnatal balb/c mice was established to explore the impact of TRX on individual neurogenesis processes in general and neuroprotective effect against ß-amyloid 1-42 (Aß42) induced inhibition in differentiation in particular. NSCs were identified exploiting immunostaining of the NSCs markers. Neurosphere clonogenic assay and BrdU/Ki67 immunostaining were employed to unravel the impact of TRX on proliferation. Differentiation experiments were carried out for a time span lasting from 48 h to 7 days utilizing ß-tubulin III and GFAP as neuronal and astrocyte marker respectively. Protective effects of TRX on Aß42 induced depression of NSCs differentiation were determined after 48 h of application. A neurosphere migration assay was carried out for 24 h in the presence and absence of TRX. Interestingly, TRX enhanced neuronal differentiation of NSCs in a dose-dependent manner after 48 h and 7 days of incubation and significantly enhanced neurite growth. A higher concentration of TRX also neutralized the inhibitory effects of Aß42 on neurite outgrowth and length after 48 h of incubation. TRX significantly stimulated cell migration. Overall, TRX not only promoted NSCs differentiation and migration but also neutralized the inhibitory effects of Aß42 on NSCs. TRX, therefore, offers an interesting lead structure from the perspective of drug design especially to promote neurogenesis in neurological disorders i.e. Alzheimer's disease.


Assuntos
Hidroxietilrutosídeo/análogos & derivados , Neuritos/efeitos dos fármacos , Crescimento Neuronal/fisiologia , Precursor de Proteína beta-Amiloide/farmacologia , Animais , Astrócitos/metabolismo , Diferenciação Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Flavonoides/farmacologia , Hidroxietilrutosídeo/metabolismo , Hidroxietilrutosídeo/farmacologia , Ventrículos Laterais/efeitos dos fármacos , Ventrículos Laterais/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Neurogênese , Neurônios/metabolismo , Neuroproteção , Fármacos Neuroprotetores/metabolismo , Fármacos Neuroprotetores/farmacologia
7.
Sci Rep ; 10(1): 6734, 2020 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-32317735

RESUMO

Oxaliplatin is a platinum-based antineoplastic drug commonly used for treating colorectal, gastric, and pancreatic cancer. However, it frequently causes peripheral neuropathy as dose-limiting toxicity and is lacking a strategy for prevention. Alogliptin, a dipeptidyl peptidase 4 (DPP-4) inhibitor, is an oral antidiabetic drug. Previous studies have shown that DPP-4 inhibitors have pleiotropic effects, including neuroprotection. In this study, we investigated the effects of alogliptin on oxaliplatin-induced peripheral neuropathy using in vitro and in vivo models. In PC12 cells, alogliptin attenuated neurite disorders induced by oxaliplatin and cisplatin. The repeated injection of oxaliplatin caused mechanical allodynia and axonal degeneration of the sciatic nerve in rats. These neuropathies were ameliorated by co-administration of alogliptin. Moreover, alogliptin did not attenuate tumor cytotoxicity of oxaliplatin in the cultured colon, gastric, or pancreatic cancer cell lines and tumor-bearing mice. These findings suggest that alogliptin may be beneficial for preventing oxaliplatin-induced peripheral neuropathy.


Assuntos
Antineoplásicos/efeitos adversos , Cisplatino/efeitos adversos , Hiperalgesia/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Oxaliplatina/efeitos adversos , Doenças do Sistema Nervoso Periférico/prevenção & controle , Piperidinas/farmacologia , Uracila/análogos & derivados , Aloenxertos , Animais , Axônios/efeitos dos fármacos , Axônios/patologia , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Relação Dose-Resposta a Droga , Células HCT116 , Humanos , Hiperalgesia/induzido quimicamente , Hiperalgesia/fisiopatologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Neuritos/efeitos dos fármacos , Neuritos/patologia , Células PC12 , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/fisiopatologia , Ratos , Ratos Sprague-Dawley , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiopatologia , Carga Tumoral/efeitos dos fármacos , Uracila/farmacologia
8.
Eur J Histochem ; 64(2)2020 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-32236088

RESUMO

Schwann cells (SC) are characterized by a remarkable plasticity that enables them to promptly respond to nerve injury promoting axonal regeneration. In peripheral nerves after damage SC convert to a repair-promoting phenotype activating a sequence of supportive functions that drive myelin clearance, prevent neuronal death, and help axon growth and guidance. Regeneration of peripheral nerves after damage correlates inversely with thrombin levels. Thrombin is not only the key regulator of the coagulation cascade but also a protease with hormone-like activities that affects various cells of the central and peripheral nervous system mainly through the protease-activated receptor 1 (PAR1). Aim of the present study was to investigate if and how thrombin could affect the axon supportive functions of SC. In particular, our results show that the activation of PAR1 in rat SC cultures with low levels of thrombin or PAR1 agonist peptides induces the release of molecules, which favor neuronal survival and neurite elongation. Conversely, the stimulation of SC with high levels of thrombin or PAR1 agonist peptides drives an opposite effect inducing SC to release factors that inhibit the extension of neurites. Moreover, high levels of thrombin administered to sciatic nerve ex vivo explants induce a dramatic change in SC morphology causing disappearance of the Cajal bands, enlargement of the Schmidt-Lanterman incisures and calcium-mediated demyelination of the paranodes. Our results indicate thrombin as a novel modulator of SC plasticity potentially able to favor or inhibit SC pro-regenerative properties according to its level at the site of lesion.


Assuntos
Neurogênese/efeitos dos fármacos , Nós Neurofibrosos/efeitos dos fármacos , Células de Schwann/efeitos dos fármacos , Trombina/farmacologia , Animais , Cálcio/metabolismo , Feminino , Masculino , Neuritos/efeitos dos fármacos , Células PC12 , Pirróis/farmacologia , Quinazolinas/farmacologia , Ratos , Ratos Wistar , Receptor PAR-1/metabolismo , Nervo Isquiático/efeitos dos fármacos , Tapsigargina/farmacologia
9.
Mol Med Rep ; 21(1): 320-328, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31939614

RESUMO

Cortex Mori Radicis extract (CMR) has various pharmacological properties, such as anti­inflammatory, anti­allergic and anti­hyperglycemic effects. However, the effects and mechanisms of CMR in the neuroregeneration of diabetic peripheral neuropathy (DPN) are unclear. In the present study, the effects of CMR on neurite outgrowth of dorsal root ganglia (DRG) neurons in diabetic rats were investigated and its underlying mechanisms were explored. SD rats were subjected to a high­fat diet with low­dose streptozotocin to induce a Type II diabetes model with peripheral neuropathy. CMR was then applied for four weeks continuously with or without injection of small interfere (si)RNA targeting the transient receptor potential canonical channel 1 (TRPC1) via the tail vein. Blood glucose levels, the number of Nissl bodies, neurite outgrowth and growth cone turning in DRG neurons were evaluated. The expression of TRPC1 protein, Ca2+ influx and activation of the PI3K/AKT signaling pathway were also investigated. The results of the present study showed that CMR significantly lowered blood glucose levels, reversed the loss of Nissl bodies, induced neurite outgrowth and restored the response of the growth cone of DRG neurons in diabetic rats. CMR exerted neurite outgrowth­promoting effects by increasing TRPC1 expression, reducing Ca2+ influx and enhancing AKT phosphorylation. siRNA targeting TRPC1 in the CMR group abrogated its anti­diabetic and neuroregenerative effects, suggesting the involvement of TRPC1 in the biological effects of CMR on DPN.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Neuropatias Diabéticas/tratamento farmacológico , Morus , Neuritos/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Extratos Vegetais/farmacologia , Animais , Glicemia/efeitos dos fármacos , Cálcio/metabolismo , Células Cultivadas , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/metabolismo , Neuropatias Diabéticas/sangue , Neuropatias Diabéticas/genética , Neuropatias Diabéticas/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/crescimento & desenvolvimento , Gânglios Espinais/metabolismo , Masculino , Neuritos/efeitos dos fármacos , Neuritos/patologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Corpos de Nissl/efeitos dos fármacos , Corpos de Nissl/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação , Extratos Vegetais/uso terapêutico , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Interferente Pequeno , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Canais de Cátion TRPC/genética , Canais de Cátion TRPC/metabolismo , Regulação para Cima
10.
Exp Neurol ; 326: 113177, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31926166

RESUMO

Preconditioning peripheral nerve injury primes the sensory neurons in the dorsal root ganglia (DRGs) to acquire axon regeneration competence. Transcription of a large set of regeneration-associated-genes (RAGs) contributes to the enhanced intrinsic axonal regeneration capacity. However, the mechanism underlying the coordinated upregulation of RAGs orchestrated by preconditioning injury is unclear. We sought to determine potential influence of DNA methylation change on transcriptional activation of RAGs in the L4-L6 DRGs following sciatic nerve injury. Genome-wide sequencing revealed that about 20% of the methylated DNA fragments were differentially methylated, and >3000 genes contained differentially methylated regions. Not only demethylation but also increased methylation was observed to a similar extent. The change in the global DNA methylation did not correlate with the gene expression level of most genes, including the well-documented RAGs. However, pharmacological inhibition or activation of DNA methylation markedly attenuated the axon growth capacity of the preconditioned DRG neurons. Pharmacological perturbation of DNA methylation resulted in simultaneous downregulation of many highly overlapping non-transcription factor RAGs, which was accompanied by a concurrent, robust upregulation of SOCS3 and Serpine1. Overexpression of SOCS3 and Serpine1 in the DRG neurons overrode injury-induced axon growth competence, corroborating their roles as the negative regulators of axon regeneration. We conclude that the injury-induced global alteration of DNA methylome strongly influences the axon growth competence in preconditioned DRG neurons. Our results also suggest a possibility that perturbing DNA methylome changes might lead to the upregulation of negative regulator RAGs thereby attenuating axon growth capacity.


Assuntos
Axônios/patologia , Metilação de DNA , Precondicionamento Isquêmico , Traumatismos dos Nervos Periféricos/patologia , Células Receptoras Sensoriais/patologia , Animais , Células Cultivadas , Metilação de DNA/efeitos dos fármacos , Gânglios Espinais/citologia , Gânglios Espinais/patologia , Regulação da Expressão Gênica/genética , Masculino , Regeneração Nervosa/genética , Neuritos/efeitos dos fármacos , Inibidor 1 de Ativador de Plasminogênio/biossíntese , Inibidor 1 de Ativador de Plasminogênio/genética , Ratos , Ratos Sprague-Dawley , Proteína 3 Supressora da Sinalização de Citocinas/biossíntese , Proteína 3 Supressora da Sinalização de Citocinas/genética , Ativação Transcricional
11.
Exp Neurol ; 324: 113115, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31734318

RESUMO

We recently identified excessive cerebral kallikrein-8 (KLK8) mRNA and protein levels at incipient stages of Alzheimer's disease (AD) in AD patients and TgCRND8 mice. Additionally, we showed that antibody-mediated KLK8 inhibition exerts therapeutic effects on AD along with enhancing neuroplasticity, resulting in improved spatial memory in mice. Mounting evidence further substantiates an important role of the protease KLK8 in neuroplasticity. In the present study we sought to gain new mechanistic insights in the interplay between KLK8, neuroplasticity and tau phosphorylation in the context of AD. We here demonstrate that KLK8 inhibition increased the number of hippocampal Ki-67 and doublecortin positive, proliferative neuronal progenitor cells in transgenic mice, whereas the same action in wildtypes had no effect. In line with these results, KLK8 inhibition reduced the levels of its pro-proliferative interaction partners KLK6 and protease-activated receptor 2 only in wildtypes, while the levels of its proliferation-supporting substrate neuregulin-1 and the non-complexed form of its complexing-partner phosphatidylethanolamine binding protein 1 were enhanced in both genotypes. Concomitant incubation of beta-amyloid (Aß)-producing primary neurons with KLK8 and its inhibitory antibody increased neurite complexity and soma size. KLK8 inhibition in SH-SY5Y cells or in primary neurons increased levels of the neuroplasticity-supporting KLK8 substrate ephrin receptor B2 (EPHB2) and total tau while decreasing the relative amount of phospho-tau in relation to total tau. KLK8 blockade further enhanced cell proliferation in SH-SY5Y cells. Additional co-incubation with an inhibitory anti-EPHB2 antibody decreased total tau levels and neurite complexity and increased the ratio of phospho-tau/total tau, underlining the key role of EPHB2 on this plastic change. In a reverse in vitro approach, KLK8 induction reduced EPHB2 and total tau and increased the ratio of phospho-tau/total tau, leading to impaired proliferation and neuronal differentiation. These results underline the therapeutic potential of KLK8 inhibition by counteracting plasticity deficits in AD-affected brain.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Calicreínas/antagonistas & inibidores , Plasticidade Neuronal/efeitos dos fármacos , Doença de Alzheimer/psicologia , Animais , Anticorpos Bloqueadores/administração & dosagem , Anticorpos Bloqueadores/farmacologia , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Humanos , Injeções Intraventriculares , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuritos/efeitos dos fármacos , Neuritos/ultraestrutura , Neurônios/efeitos dos fármacos , Fosforilação , Receptor EphB2/antagonistas & inibidores , Receptor EphB2/imunologia , Receptor EphB2/metabolismo , Memória Espacial , Proteínas tau/metabolismo
12.
J Orthop Res ; 38(5): 1016-1026, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31825104

RESUMO

Pain originating from an intervertebral disc (discogenic pain) is a major source of chronic low back pain. Pathological innervation of the disc by pain-sensing nerve fibers is thought to be a key component of discogenic pain, so treatment with biomaterials that have the ability to inhibit neurite growth will greatly benefit novel disc therapeutics. Currently, disc therapeutic biomaterials are rarely screened for their ability to modulate nerve growth, mainly due to a lack of models to screen neuromodulation. To address this deficit, our lab has engineered a three dimensional in vitro disc innervation model that mimics the interface between primary sensory nerves and the intervertebral disc. Further, herein we have demonstrated the utility of this model to screen the efficacy of chondroitin sulfate biomaterials to inhibit nerve fiber invasion into the model disc. Biomaterials containing chondroitin-4-sulfate (CS-A) decrease neurite growth in a uniform gel and at an interface between a growth-permissive and a growth-inhibitory gel, while chondroitin-6-sulfate (CS-C) is less neuroinhibitory. This in vitro model holds great potential for screening inhibitors of nerve fiber growth to further improve intervertebral disc replacements and therapeutics. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:1016-1026, 2020.


Assuntos
Sulfatos de Condroitina/administração & dosagem , Técnicas de Cultura , Disco Intervertebral/inervação , Neuritos/efeitos dos fármacos , Animais , Materiais Biocompatíveis , Hidrogéis , Ratos
13.
J Med Chem ; 63(2): 490-511, 2020 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-31518122

RESUMO

Injury to the adult central nervous system (CNS) usually leads to permanent deficits of cognitive, sensory, and/or motor functions. The failure of axonal regeneration in the damaged CNS limits functional recovery. The lack of information concerning the biological mechanism of axonal regeneration and its complexity has delayed the process of drug discovery for many years compared to other drug classes. Starting in the early 2000s, the ability of many molecules to stimulate axonal regrowth was evaluated through automated screening techniques; many hits and some new mechanisms involved in axonal regeneration were identified. In this Perspective, we discuss the rise of the CNS regenerative drugs, the main biological techniques used to test these drug candidates, some of the most important screens performed so far, and the main challenges following the identification of a drug that is able to induce axonal regeneration in vivo.


Assuntos
Fármacos do Sistema Nervoso Central/farmacologia , Regeneração Nervosa/efeitos dos fármacos , Animais , Axônios/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Humanos , Neuritos/efeitos dos fármacos
14.
Brain ; 143(1): 266-288, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31848580

RESUMO

Huntington's disease is associated with a reactive microglial response and consequent inflammation. To address the role of these cells in disease pathogenesis, we depleted microglia from R6/2 mice, a rapidly progressing model of Huntington's disease marked by behavioural impairment, mutant huntingtin (mHTT) accumulation, and early death, through colony-stimulating factor 1 receptor inhibition (CSF1Ri) with pexidartinib (PLX3397) for the duration of disease. Although we observed an interferon gene signature in addition to downregulated neuritogenic and synaptic gene pathways with disease, overt inflammation was not evident by microglial morphology or cytokine transcript levels in R6/2 mice. Nonetheless, CSF1Ri-induced microglial elimination reduced or prevented disease-related grip strength and object recognition deficits, mHTT accumulation, astrogliosis, and striatal volume loss, the latter of which was not associated with reductions in cell number but with the extracellular accumulation of chondroitin sulphate proteoglycans (CSPGs)-a primary component of glial scars. A concurrent loss of proteoglycan-containing perineuronal nets was also evident in R6/2 mice, and microglial elimination not only prevented this but also strikingly increased perineuronal nets in the brains of naïve littermates, suggesting a new role for microglia as homeostatic regulators of perineuronal net formation and integrity.


Assuntos
Aminopiridinas/farmacologia , Matriz Extracelular/efeitos dos fármacos , Proteína Huntingtina/efeitos dos fármacos , Doença de Huntington/metabolismo , Microglia/efeitos dos fármacos , Neostriado/efeitos dos fármacos , Pirróis/farmacologia , Reconhecimento Psicológico/efeitos dos fármacos , Animais , Astrócitos/efeitos dos fármacos , Proteoglicanas de Sulfatos de Condroitina/efeitos dos fármacos , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Citocinas/efeitos dos fármacos , Citocinas/genética , Modelos Animais de Doenças , Regulação para Baixo , Matriz Extracelular/metabolismo , Força da Mão , Humanos , Proteína Huntingtina/genética , Proteína Huntingtina/metabolismo , Doença de Huntington/genética , Doença de Huntington/patologia , Doença de Huntington/fisiopatologia , Inflamação , Camundongos , Camundongos Transgênicos , Neostriado/patologia , Neuritos/efeitos dos fármacos , RNA Mensageiro/metabolismo , Receptores de Fator Estimulador das Colônias de Granulócitos e Macrófagos/antagonistas & inibidores , Sinapses/efeitos dos fármacos , Transcriptoma
15.
Histochem Cell Biol ; 153(3): 177-184, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31879799

RESUMO

Zonisamide, an anti-epileptic and anti-Parkinson's disease drug, displays neurotrophic activity on cultured motor neurons and facilitates axonal regeneration after peripheral nerve injury in mice, but its underlying mechanisms remain unclear. In this study, zonisamide enhanced neurite outgrowth from cultured adult rat dorsal root ganglion (DRG) neurons in a concentration-dependent manner (1 µM < 10 µM < 100 µM), and its activity was significantly attenuated by co-treatment with a phosphatidyl inositol-3'-phosphate-kinase (PI3K) inhibitor LY294002 or a mitogen-activated protein kinase (MAPK) inhibitor U0126. In agreement with these findings, 100 µM zonisamide for 1 h induced phosphorylation of AKT and ERK1/2, key molecules of PI3K and MAPK signaling pathways, respectively in mouse neuroblastoma × rat DRG neuron hybrid cells ND7/23. In contrast, zonisamide failed to promote proliferation or migration of immortalized Fischer rat Schwann cells 1 (IFRS1). These findings suggest that the beneficial effects of zonisamide on peripheral nerve regeneration may be attributable to its direct actions on neurons through PI3K and MAPK pathways, rather than the stimulation of Schwann cells.


Assuntos
Anticonvulsivantes/farmacologia , Gânglios Espinais/efeitos dos fármacos , Neuritos/efeitos dos fármacos , Crescimento Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Zonisamida/farmacologia , Animais , Movimento Celular , Proliferação de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Gânglios Espinais/metabolismo , Neuritos/metabolismo , Neurônios/metabolismo , Ratos , Ratos Wistar , Células de Schwann/citologia , Células de Schwann/metabolismo , Relação Estrutura-Atividade
16.
J Alzheimers Dis ; 73(2): 517-528, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31796678

RESUMO

The cell surface level of apolipoprotein E receptor 2 (ApoER2) increases by cyclic transport of ApoER2 and then activates Reelin signaling pathway to exert neuroprotective function in AD. ApoER2 ligand Apolipoprotein E4 (ApoE4) inhibits the recycling of ApoER2 to the cell surface rendering neurons unresponsive to Reelin. Carnosic acid (CA) is proven to possess neuroprotective and neurotrophic functions in Alzheimer's disease (AD) mouse model. However, there are few reports about how ApoE4 impairs the recycling of ApoER2 and if CA can affect the cyclic transport of ApoER2. In this study, we demonstrated that ApoE4 attenuates the binding of sorting nexin 17 (SNX17) to ApoER2 and inhibits the recycling of ApoER2, resulting in decreased cell surface level of ApoER2. Further, we found that CA enhances the binding of SNX17 to ApoER2, counteracts the negative effects of ApoE4 on the cell surface level of ApoER2 to reverse the ApoE4-induced reduction in Reelin signaling activation by increasing the phosphorylation of the N-methyl-D-aspartate receptor (NMDAR) and cAMP-response element-binding protein (CREB) and the expression of Gria2. Thus, CA promotes neurite growth inhibited by ApoE4. Our work suggests that CA may be a potential approach to attenuate the risk of ApoE4-associated AD.


Assuntos
Abietanos/farmacologia , Apolipoproteína E4/antagonistas & inibidores , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/antagonistas & inibidores , Proteínas do Tecido Nervoso/metabolismo , Fármacos Neuroprotetores/farmacologia , Serina Endopeptidases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Feminino , Humanos , Proteína-1 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Neuritos/efeitos dos fármacos , Células PC12 , Gravidez , Ratos , Receptores de AMPA/biossíntese , Receptores de AMPA/genética , Receptores de Superfície Celular/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Nexinas de Classificação/metabolismo
17.
Am J Physiol Gastrointest Liver Physiol ; 318(1): G53-G65, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31682159

RESUMO

Detection of nutritional and noxious food components in the gut is a crucial component of gastrointestinal function. Contents in the gut lumen interact with enteroendocrine cells dispersed throughout the gut epithelium. Enteroendocrine cells release many different hormones, neuropeptides, and neurotransmitters that communicate either directly or indirectly with the central nervous system and the enteric nervous system, a network of neurons and glia located within the gut wall. Several populations of enteric neurons extend processes that innervate the gastrointestinal lamina propria; however, how these processes develop and begin to transmit information from the mucosa is not fully understood. In this study, we found that Tuj1-immunoreactive neurites begin to project out of the myenteric plexus at embryonic day (E)13.5 in the mouse small intestine, even before the formation of villi. Using live calcium imaging, we discovered that neurites were capable of transmitting electrical information from stimulated villi to the plexus by E15.5. In unpeeled gut preparations where all layers were left intact, we also mimicked the basolateral release of 5-HT from enteroendocrine cells, which triggered responses in myenteric cell bodies at postnatal day (P)0. Altogether, our results show that enteric neurons extend neurites out of the myenteric plexus early during mouse enteric nervous system development, innervating the gastrointestinal mucosa, even before villus formation in mice of either sex. Neurites are already able to conduct electrical information at E15.5, and responses to 5-HT develop postnatally.NEW & NOTEWORTHY How enteric neurons project into the gut mucosa and begin to communicate with the epithelium during development is not known. Our study shows that enteric neurites project into the lamina propria as early as E13.5 in the mouse, before development of the submucous plexus and before formation of intestinal villi. These neurites are capable of transmitting electrical signals back to their cell bodies by E15.5 and respond to serotonin applied to neurite terminals by birth.


Assuntos
Mucosa Intestinal/inervação , Intestino Delgado/inervação , Microvilosidades/fisiologia , Plexo Mientérico/crescimento & desenvolvimento , Neuritos/fisiologia , Neurogênese , Animais , Células Enteroendócrinas/metabolismo , Células Enteroendócrinas/fisiologia , Potenciais Evocados , Feminino , Idade Gestacional , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Plexo Mientérico/efeitos dos fármacos , Plexo Mientérico/metabolismo , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Serotonina/farmacologia , Tubulina (Proteína)/metabolismo
18.
Sci Rep ; 9(1): 19353, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31852910

RESUMO

Neuroblastoma is the most commonly diagnosed extracranial tumor in the first year of life. Approximately 9% of neuroblastoma patients present germline or somatic aberrations in the gene encoding for anaplastic lymphoma kinase (ALK). This increases in high-risk neuroblastomas, which have a 14% frequency of ALK aberrations at the time of diagnosis and show increasing numbers at relapse. Abrogating ALK activity with kinase inhibitors is employed as clinical therapy in malignancies such as non-small cell lung cancer and has shown good results in pediatric inflammatory myofibroblastic tumors and anaplastic large cell lymphomas. A phase I clinical trial of the first generation ALK inhibitor, crizotinib, in neuroblastoma patients showed modest results and suggested that further investigation was needed. Continuous development of ALK inhibitors has resulted in the third generation inhibitor repotrectinib (TPX-0005), which targets the active kinase conformations of ALK, ROS1 and TRK receptors. In the present study we investigated the effects of repotrectinib in a neuroblastoma setting in vitro and in vivo. Neuroblastoma cell lines were treated with repotrectinib to investigate inhibition of ALK and to determine its effect on proliferation. PC12 cells transfected with different ALK mutant variants were used to study the efficacy of repotrectinib to block ALK activation/signaling. The in vivo effect of repotrectinib was also analyzed in a neuroblastoma xenograft model. Our results show that repotrectinib is capable of inhibiting signaling activity of a range of ALK mutant variants found in neuroblastoma patients and importantly it exhibits strong antitumor effects in a xenograft model of neuroblastoma.


Assuntos
Quinase do Linfoma Anaplásico/metabolismo , Compostos Macrocíclicos/uso terapêutico , Neuroblastoma/tratamento farmacológico , Neuroblastoma/patologia , Pirazóis/uso terapêutico , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Humanos , Concentração Inibidora 50 , Compostos Macrocíclicos/farmacologia , Camundongos Endogâmicos BALB C , Mutação/genética , Neovascularização Patológica/tratamento farmacológico , Neuritos/efeitos dos fármacos , Neuritos/metabolismo , Neuroblastoma/irrigação sanguínea , Neuroblastoma/enzimologia , Células PC12 , Fosforilação/efeitos dos fármacos , Poli(ADP-Ribose) Polimerases/metabolismo , Pirazóis/farmacologia , Ratos , Ensaios Antitumorais Modelo de Xenoenxerto
19.
BMC Complement Altern Med ; 19(1): 339, 2019 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-31783843

RESUMO

BACKGROUND: The dried fruits of Forsythia suspensa has generally been used to clear heat and detoxify in traditional Korean and Chinese medicine. Oxaliplatin is a first-line treatment chemotherapeutic agent for advanced colorectal cancer, but it induces peripheral neuropathy as an adverse side effect affecting the treatment regimen and the patient's quality of life. The present study was conducted to evaluate the neuroprotective effects of an aqueous extract of F. suspensa fruits (EFSF) on oxaliplatin-induced peripheral neuropathy. METHODS: The chemical components from EFSF were characterized and quantified using the ultra-high performance liquid chromatography-diode array detector system. The cytotoxicities of anticancer drugs in cancer cells and PC12 cells were assessed by the Ez-Cytox viability assay. To measure the in vitro neurotoxicity, the neurite outgrowth was analyzed in the primary dorsal root ganglion (DRG) cells, and neural PC12 cells that were differentiated with nerve growth factor. To evaluate the in vivo neuroprotective activity, the von Frey test was performed in six-week-old male mice (C57BL/6) receiving EFSF (60-600 mg/kg) in the presence of 20-30 mg/kg cumulative doses of oxaliplatin. Thereafter, the mice were euthanized for immunohistochemical staining analysis with an antibody against PGP9.5. RESULTS: EFSF attenuated the cytotoxic activities of the various anticancer drugs in neural PC12 cells, but did not affect the anticancer activity of oxaliplatin in human cancer cells. Oxaliplatin remarkably induced neurotoxicities including cytotoxicity and the inhibited neurite outgrowth of DRG and neural PC12 cells. However, the co-treatment of EFSF (100 µg/ml) with oxaliplatin completely reversed the oxaliplatin-induced neurotoxicity. Forsythoside A, the major component of EFSF, also exerted remarkable neuroprotective effects against the oxaliplatin-induced neurotoxicity. In addition, EFSF (60-200 mg/kg) significantly alleviated the oxaliplatin-induced mechanical allodynia and loss of intra-epidermal nerve fiber to the levels of the vehicle control in the mouse peripheral neuropathy model. CONCLUSIONS: EFSF could be considered a useful herbal medicine for the treatment of peripheral neuropathy in cancer patients receiving chemotherapy with oxaliplatin.


Assuntos
Forsythia , Fármacos Neuroprotetores/farmacologia , Oxaliplatina/toxicidade , Extratos Vegetais/farmacologia , Animais , Antineoplásicos/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Frutas/química , Células HCT116 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neuritos/efeitos dos fármacos , Neurotoxinas/toxicidade , Células PC12 , Ratos
20.
PLoS One ; 14(10): e0224022, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31671109

RESUMO

Neurotrophins and their mimetics are potential treatments for hearing disorders because of their trophic effects on spiral ganglion neurons (SGNs) whose connections to hair cells may be compromised in many forms of hearing loss. Studies in noise or ototoxin-exposed animals have shown that local delivery of NT-3 or BDNF has beneficial effects on SGNs and hearing. We evaluated several TrkB or TrkC monoclonal antibody agonists and small molecules, along with BDNF and NT-3, in rat cochlea ex vivo models. The TrkB agonists BDNF and a monoclonal antibody, M3, had the greatest effects on SGN survival, neurite outgrowth and branching. In organotypic cochlear explants, BDNF and M3 enhanced synapse formation between SGNs and inner hair cells and restored these connections after excitotoxin-induced synaptopathy. Loss of these synapses has recently been implicated in hidden hearing loss, a condition characterized by difficulty hearing speech in the presence of background noise. The unique profile of M3 revealed here warrants further investigation, and the broad activity profile of BDNF observed underpins its continued development as a hearing loss therapeutic.


Assuntos
Anticorpos Monoclonais/imunologia , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Cóclea/citologia , Perda Auditiva/patologia , Neuritos/metabolismo , Receptor trkA/agonistas , Sinapses/metabolismo , Animais , Linhagem Celular , Sobrevivência Celular , Modelos Animais de Doenças , Perda Auditiva/imunologia , Humanos , Neuritos/efeitos dos fármacos , Neuritos/imunologia , Ratos , Receptor trkA/imunologia , Sinapses/efeitos dos fármacos , Sinapses/imunologia
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