RESUMEN

BACKGROUND: The emergence of the Nerve Growth Factor (NGF) has promoted the development of neuroprotective therapy; however, it has little effect on cerebral ischemia because of its poor Blood-Brain Barrier (BBB) permeability. Specific Mode Electroacupuncture Stimulation (SMES) can open BBB safely and effectively; however, it has shown inconclusive clinical effects and indirect clinical evidence in the recovery phase. Hence, the authors conducted a multicentre, randomized, placebo-controlled, assessor-blinded clinical trial to assess the effectiveness and safety of SMES combined with NGF treatment used during ischaemic stroke recovery. METHODS: A total of 288 stroke patients from three hospitals will be recruited and randomly allocated to four groups: acupuncture + placebo, acupuncture + NGF, SMES + placebo, and SMES + NGF, in a 1:1:1:1 ratio. Assessment data will be collected at baseline, 2-weeks, and 4-weeks during the treatment period, as well as at the 4-week and 8-week follow-up after treatment completion. The primary outcome measure will be the basic cure rate. The secondary outcome measures include the simplified Modified Barthel Index, Timed Up and Go Test, Fugl-Meyer Assessment of Motor Function Score, Tinetti Performance Oriented Mobility Assessment, Montreal Cognitive Assessment, and Loewenstein Occupational Therapy Cognitive Assessment. Moreover, resting-state functional magnetic resonance imaging and Functional near-infrared spectroscopy can detect changes in cerebral blood flow and brain function and investigate the relationship between the clinical efficacy and mechanism of the prescribed interventions. CONCLUSION: This study will provide clinical evidence for the efficacy and safety of SMES combined with NGF in the treatment of stroke patients.

Asunto(s)

Electroacupuntura , Accidente Cerebrovascular Isquémico , Factor de Crecimiento Nervioso , Humanos , Electroacupuntura/métodos , Accidente Cerebrovascular Isquémico/terapia , Resultado del Tratamiento , Terapia Combinada , Masculino , Femenino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Adulto

RESUMEN

The nerve growth factor (NGF) participates in cell survival and glucose-stimulated insulin secretion (GSIS) processes in rat adult beta cells. GSIS is a complex process in which metabolic events and ionic channel activity are finely coupled. GLUT2 and glucokinase (GK) play central roles in GSIS by regulating the rate of the glycolytic pathway. The biphasic release of insulin upon glucose stimulation characterizes mature adult beta cells. On the other hand, beta cells obtained from neonatal, suckling, and weaning rats are considered immature because they secrete low levels of insulin and do not increase insulin secretion in response to high glucose. The weaning of rats (at postnatal day 20 in laboratory conditions) involves a dietary transition from maternal milk to standard chow. It is characterized by increased basal plasma glucose levels and insulin levels, which we consider physiological insulin resistance. On the other hand, we have observed that incubating rat beta cells with NGF increases GSIS by increasing calcium currents in neonatal cells. In this work, we studied the effects of NGF on the regulation of cellular distribution and activity of GLUT2 and GK to explore its potential role in the maturation of GSIS in beta cells from P20 rats. Pancreatic islet cells from both adult and P20 rats were isolated and incubated with 5.6 mM or 15.6 mM glucose with and without NGF for 4 hours. Specific immunofluorescence assays were conducted following the incubation period to detect insulin and GLUT2. Additionally, we measured glucose uptake, glucokinase activity, and insulin secretion assays at 5.6 mM or 15.6 mM glucose concentrations. We observed an age-dependent variation in the distribution of GLUT2 in pancreatic beta cells and found that glucose plays a regulatory role in GLUT2 distribution independently of age. Moreover, NGF increases GLUT2 abundance, glucose uptake, and GSIS in P20 beta cells and GK activity in adult beta cells. Our results suggest that besides increasing calcium currents, NGF regulates metabolic components of the GSIS, thereby contributing to the maturation process of pancreatic beta cells.

Asunto(s)

Glucoquinasa , Transportador de Glucosa de Tipo 2 , Glucosa , Células Secretoras de Insulina , Factor de Crecimiento Nervioso , Animales , Masculino , Ratas , Células Cultivadas , Glucoquinasa/metabolismo , Glucosa/metabolismo , Transportador de Glucosa de Tipo 2/metabolismo , Insulina/metabolismo , Secreción de Insulina/efectos de los fármacos , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/efectos de los fármacos , Factor de Crecimiento Nervioso/metabolismo , Factor de Crecimiento Nervioso/farmacología , Ratas Wistar

RESUMEN

Orofacial nerve injuries may result in temporary or long-term loss of sensory function and decreased quality of life in patients. B vitamins are required for DNA synthesis and the repair and maintenance of phospholipids. In particular, vitamins B1, B6, and B12 are essential for neuronal function. Deficiency in vitamin B complex (VBC) has been linked to increased oxidative stress, inflammation and demyelination. Photobiomodulation (PBM) has antioxidant activity and is neuroprotective. In addition, a growing literature attests to the positive effects of PBM on nerve repair. To assess the effect of PBM and VBC on regenerative process we evaluated the expression of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), myelin basic protein (MBP), laminin and neurofilaments (NFs) using Western blotting to identify regenerative pattern after chronic constriction injury of the infraorbital nerve (CCI IoN) treated by PBM, VBC or its combination. After CCI IoN, the rats were divided into six groups naive, sham, injured (CCI IoN), treated with photobiomodulation (904 nm, 6.23 J/cm2, CCI IoN + PBM), treated with VBC (containing B1, B6 and B12) 5 times, CCI IoN + VBC) and treated with PBM and VBC (CCI IoN + VBC + PBM). The treatments could revert low expression of BDNF, MBP and laminin. Also reverted the higher expression of neurofilaments and enhanced expression of NGF. PBM and VBC could accelerate injured infraorbital nerve repair in rats through reducing the expression of neurofilaments, increasing the expression of BDNF, laminin and MBP and overexpressing NGF. These data support the notion that the use of PBM and VBC may help in the treatment of nerve injuries. This finding has potential clinical applications.

Asunto(s)

Factor Neurotrófico Derivado del Encéfalo , Modelos Animales de Enfermedad , Terapia por Luz de Baja Intensidad , Factor de Crecimiento Nervioso , Regeneración Nerviosa , Complejo Vitamínico B , Animales , Ratas , Regeneración Nerviosa/efectos de la radiación , Terapia por Luz de Baja Intensidad/métodos , Factor Neurotrófico Derivado del Encéfalo/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Masculino , Laminina/metabolismo , Traumatismos del Nervio Facial/radioterapia , Traumatismos del Nervio Facial/terapia , Ratas Wistar , Proteína Básica de Mielina/metabolismo

RESUMEN

We investigated the locomotor muscle metaboreflex control of ventilation, circulation, and dyspnea in patients with chronic obstructive pulmonary disease (COPD). Ten patients [forced expiratory volume in 1 second (FEV1; means ± SD) = 43 ± 17% predicted] and nine age- and sex-matched controls underwent 1) cycling exercise followed by postexercise circulatory occlusion (PECO) to activate the metaboreflex or free circulatory flow to inactivate it, 2) cold pressor test to interpret whether any altered reflex response was specific to the metaboreflex arc, and 3) muscle biopsy to explore the metaboreflex arc afferent side. We measured airflow, dyspnea, heart rate, arterial pressure, muscle blood flow, and vascular conductance during reflexes activation. In addition, we measured fiber types, glutathione redox balance, and metaboreceptor-related mRNAs in the vastus lateralis. Metaboreflex activation increased ventilation versus free flow in patients (∼15%, P < 0.020) but not in controls (P > 0.450). In contrast, metaboreflex activation did not change dyspnea in patients (P = 1.000) but increased it in controls (∼100%, P < 0.001). Other metaboreflex-induced responses were similar between groups. Cold receptor activation increased ventilation similarly in both groups (P = 0.46). Patients had greater type II skeletal myocyte percentage (14%, P = 0.010), lower glutathione ratio (-34%, P = 0.015), and lower nerve growth factor (NGF) mRNA expression (-60%, P = 0.031) than controls. Therefore, COPD altered the locomotor muscle metaboreflex control of ventilation. It increased type II myocyte percentage and elicited redox imbalance, potentially producing more muscle metaboreceptor stimuli. Moreover, it decreased NGF expression, suggesting a downregulation of metabolically sensitive muscle afferents.NEW & NOTEWORTHY This study's integrative physiology approach provides evidence for a specific alteration in locomotor muscle metaboreflex control of ventilation in patients with COPD. Furthermore, molecular analyses of a skeletal muscle biopsy suggest that the amount of muscle metaboreceptor stimuli derived from type II skeletal myocytes and redox imbalance overcame a downregulation of metabolically sensitive muscle afferents.

Asunto(s)

Factor de Crecimiento Nervioso , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Factor de Crecimiento Nervioso/metabolismo , Reflejo/fisiología , Músculo Esquelético/fisiología , Disnea , Glutatión/metabolismo , Presión Sanguínea/fisiología

RESUMEN

PURPOSE: To evaluate the neuroprotective effects of Rilmenidine on diabetic peripheral neuropathy (DPN) in a rat model of diabetes induced by streptozotocin (STZ). METHODS: STZ (60 mg/kg) was administered to adult Sprague-Dawley rats to induce diabetes. On the 30th day after STZ administration, electromyography (EMG) and motor function tests confirmed the presence of DPN. Group 1: Control (n = 10), Group 2: DM + 0.1 mg/kg Rilmenidine (n = 10), and Group 3: DM + 0.2 mg/kg Rilmenidine (n = 10) were administered via oral lavage for four weeks. EMG, motor function test, biochemical analysis, and histological and immunohistochemical analysis of sciatic nerves were then performed. RESULTS: The administration of Rilmenidine to diabetic rats substantially reduced sciatic nerve inflammation and fibrosis and prevented electrophysiological alterations. Immunohistochemistry of sciatic nerves from saline-treated rats revealed increased perineural thickness, HMGB-1, tumor necrosis factor-α, and a decrease in nerve growth factor (NGF), LC-3. In contrast, Rilmendine significantly inhibited inflammation markers and prevented the reduction in NGF expression. In addition, Rilmenidine significantly decreased malondialdehyde and increased diabetic rats' total antioxidative capacity. CONCLUSIONS: The findings of this study suggest that Rilmenidine may have therapeutic effects on DNP by modulating antioxidant and autophagic pathways.

Asunto(s)

Diabetes Mellitus Experimental , Neuropatías Diabéticas , Ratas , Animales , Neuropatías Diabéticas/tratamiento farmacológico , Neuropatías Diabéticas/patología , Ratas Sprague-Dawley , Diabetes Mellitus Experimental/complicaciones , Diabetes Mellitus Experimental/tratamiento farmacológico , Diabetes Mellitus Experimental/patología , Rilmenidina/farmacología , Rilmenidina/uso terapéutico , Factor de Crecimiento Nervioso/metabolismo , Factor de Crecimiento Nervioso/farmacología , Factor de Crecimiento Nervioso/uso terapéutico , Nervio Ciático/patología , Antioxidantes/uso terapéutico , Inflamación/patología

RESUMEN

This study aimed to evaluate Haloperidol's (Hal) effects on the behavioral, neurotrophic factors, and epigenetic parameters in an animal model of schizophrenia (SCZ) induced by ketamine (Ket). Injections of Ket or saline were administered intraperitoneal (once a day) between the 1st and 14th days of the experiment. Water or Hal was administered via gavage between the 8th and 14th experimental days. Thirty minutes after the last injection, the animals were subjected to behavioral analysis. The activity of DNA methyltransferase (DNMT), histone deacetylase (HDAC), and histone acetyltransferase and levels of brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT-3), and glial-derived neurotrophic factor (GDNF) were evaluated in the frontal cortex, hippocampus, and striatum. Ket increased the covered distance and time spent in the central area of the open field, and Hal did not reverse these behavioral alterations. Significant increases in the DNMT and HDAC activities were detected in the frontal cortex and striatum from rats that received Ket, Hal, or a combination thereof. Besides, Hal per se increased the activity of DNMT and HDAC in the hippocampus of rats. Hal per se or the association of Ket plus Hal decreased BDNF, NGF, NT-3, and GDNF, depending on the brain region and treatment regimen. The administration of Hal can alter the levels of neurotrophic factors and the activity of epigenetic enzymes, which can be a factor in the development of effect collateral in SCZ patients. However, the precise mechanisms involved in these alterations are still unclear.

Asunto(s)

Ketamina , Esquizofrenia , Humanos , Ratas , Animales , Haloperidol/farmacología , Esquizofrenia/inducido químicamente , Esquizofrenia/tratamiento farmacológico , Esquizofrenia/genética , Ketamina/toxicidad , Factor Neurotrófico Derivado del Encéfalo/genética , Factor Neurotrófico Derivado de la Línea Celular Glial , Factor de Crecimiento Nervioso/genética , Modelos Animales de Enfermedad , Epigénesis Genética

RESUMEN

Nerve growth factor (NGF) was the first neurotrophin described. This neurotrophin contributes to organogenesis by promoting sensory innervation and angiogenesis in the endocrine and immune systems. Neuronal and non-neuronal cells produce and secrete NGF, and several cell types throughout the body express the high-affinity neurotrophin receptor TrkA and the low-affinity receptor p75NTR. NGF is essential for glucose-stimulated insulin secretion and the complete development of pancreatic islets. Plus, this factor is involved in regulating lipolysis and thermogenesis in adipose tissue. Immune cells produce and respond to NGF, modulating their inflammatory phenotype and the secretion of cytokines, contributing to insulin resistance and metabolic homeostasis. This neurotrophin regulates the synthesis of gonadal steroid hormones, which ultimately participate in the metabolic homeostasis of other tissues. Therefore, we propose that this neurotrophin's imbalance in concentrations and signaling during metabolic syndrome contribute to its pathophysiology. In the present work, we describe the multiple roles of NGF in immunoendocrine organs that are important in metabolic homeostasis and related to the pathophysiology of metabolic syndrome.

Asunto(s)

Síndrome Metabólico , Factor de Crecimiento Nervioso , Humanos , Síndrome Metabólico/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Neuronas/metabolismo , Receptor de Factor de Crecimiento Nervioso/metabolismo , Receptor trkA/metabolismo , Receptores de Factor de Crecimiento Nervioso/metabolismo

RESUMEN

Doxycycline (DOX) is a widely used antibiotic that is able to cross the blood-brain barrier. Several studies have shown its neuroprotective effect against neurodegeneration and have associated it with antioxidant, anti-apoptotic, and anti-inflammatory mechanisms. We have recently demonstrated that DOX mimics nerve growth factor (NGF) signaling in PC12 cells. However, the involvement of this mechanism in the neuroprotective effect of DOX is unknown. Axonal degeneration and synaptic loss are key events at the early stages of neurodegeneration, and precede the neuronal death in neurodegenerative diseases, including Parkinson's disease (PD). Therefore, the regeneration of the axonal and synaptic network might be beneficial in PD. The effect of DOX in PC12 cells treated with the Parkinsonian neurotoxin 1-methyl-4-phenylpyridinium (MPP+) was addressed. Doxycycline reduced the inhibition of neuritogenesis induced by MPP+, even in cells deprived of NGF. The mechanism involved the upregulation of GAP-43, synapsin I, ß-III-tubulin, F-actin, and neurofilament-200, proteins that are associated with axonal and synaptic plasticity. Considering the role of axonal degeneration and synaptic loss at the initial stages of PD, the recent advances in early diagnosis of neurodegeneration, and the advantages of drug repurposing, doxycycline is a promising candidate to treat PD.

Asunto(s)

Fármacos Neuroprotectores , Enfermedad de Parkinson , Ratas , Animales , Humanos , Regulación hacia Arriba , Doxiciclina/farmacología , Doxiciclina/uso terapéutico , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Factor de Crecimiento Nervioso/metabolismo , Factor de Crecimiento Nervioso/uso terapéutico , Proteínas/metabolismo , Enfermedad de Parkinson/tratamiento farmacológico , Células PC12 , Tubulina (Proteína)/metabolismo , 1-Metil-4-fenilpiridinio/toxicidad , 1-Metil-4-fenilpiridinio/uso terapéutico

RESUMEN

The pathophysiology of sepsis may involve the activation of the NOD-type receptor containing the pyrin-3 domain (NLPR-3), mitochondrial and oxidative damages. One of the primary essential oxidation products is 8-oxoguanine (8-oxoG), and its accumulation in mitochondrial DNA (mtDNA) induces cell dysfunction and death, leading to the hypothesis that mtDNA integrity is crucial for maintaining neuronal function during sepsis. In sepsis, the modulation of NLRP-3 activation is critical, and mefenamic acid (MFA) is a potent drug that can reduce inflammasome activity, attenuating the acute cerebral inflammatory process. Thus, this study aimed to evaluate the administration of MFA and its implications for the reduction of inflammatory parameters and mitochondrial damage in animals submitted to polymicrobial sepsis. To test our hypothesis, adult male Wistar rats were submitted to the cecal ligation and perforation (CLP) model for sepsis induction and after receiving an injection of MFA (doses of 10, 30, and 50 mg/kg) or sterile saline (1 mL/kg). At 24 h after sepsis induction, the frontal cortex and hippocampus were dissected to analyze the levels of TNF-α, IL-1ß, and IL-18; oxidative damage (thiobarbituric acid reactive substances (TBARS), carbonyl, and DCF-DA (oxidative parameters); protein expression (mitochondrial transcription factor A (TFAM), NLRP-3, 8-oxoG; Bax, Bcl-2 and (ionized calcium-binding adaptor molecule 1 (IBA-1)); and the activity of mitochondrial respiratory chain complexes. It was observed that the septic group in both structures studied showed an increase in proinflammatory cytokines mediated by increased activity in NLRP-3, with more significant oxidative damage and higher production of reactive oxygen species (ROS) by mitochondria. Damage to mtDNA it was also observed with an increase in 8-oxoG levels and lower levels of TFAM and NGF-1. In addition, this group had an increase in pro-apoptotic proteins and IBA-1 positive cells. However, MFA at doses of 30 and 50 mg/kg decreased inflammasome activity, reduced levels of cytokines and oxidative damage, increased bioenergetic efficacy and reduced production of ROS and 8-oxoG, and increased levels of TFAM, NGF-1, Bcl-2, reducing microglial activation. As a result, it is suggested that MFA induces protection in the central nervous system early after the onset of sepsis.

Asunto(s)

Ácido Mefenámico , Sepsis , Animales , Ratas , Masculino , Especies Reactivas de Oxígeno/metabolismo , Ácido Mefenámico/metabolismo , Ácido Mefenámico/farmacología , Ratas Wistar , Inflamasomas/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Mitocondrias , Sepsis/complicaciones , Sepsis/tratamiento farmacológico , ADN Mitocondrial , Citocinas/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo

RESUMEN

HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is a neurodegenerative disease that leads to motor impairment due to a chronic inflammatory process in the central nervous system (CNS). However, the HAM/TSP pathogenesis is not completely clear, and biomarkers to define the disease prognosis are still necessary. Thus, we aimed to identify biomarkers for HAM/TSP and potential mechanisms involved in disease development. To that end, the concentrations of VILIP-1, BDNF, VEGF, ß-NGF, TGF-ß1, fractalkine/CX3CL1, IL-6, IL-18, and TNF-α, and the soluble forms of TREM-1, TREM-2, and RAGE, were assessed using a multiplex bead-based immunoassay in paired cerebrospinal fluid (CSF) and serum samples from HAM/TSP patients (n = 20), asymptomatic HTLV-1 carriers (AC) (n = 13), and HTLV-1-seronegative individuals (n = 9), with the results analyzed according to the speed of HAM/TSP progression. HAM/TSP patients had elevated fractalkine in the serum but not in the CSF, particularly those with low neuroinflammatory activity (CSF/serum ratio of neopterin <1 and of CXCL10 < 2). HAM/TSP patients with normal CSF levels of neurofilament light chain (NfL) showed elevated ß-NGF in serum, and serum BDNF levels were increased in HTLV-1-infected individuals, particularly in HTLV-1 AC. Both HTLV-1 AC and HAM/TSP patients had lower TGF-ß1 levels in CSF compared to uninfected individuals, and HAM/TSP patients with active CNS inflammation showed higher CSF levels of IL-18, which correlated with markers of inflammation, neuronal death, and blood−brain-barrier permeability. Although none of the factors evaluated were associated with the speed of HAM/TSP progression, reduced TGF-ß1 levels in CSF suggest that suppressive responses to control subclinical and/or active neurodegeneration are impaired, while increased CSF IL-18 indicates the involvement of inflammasome-mediated mechanisms in HAM/TSP development.

Asunto(s)

Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Enfermedades Neurodegenerativas , Paraparesia Espástica Tropical , Humanos , Quimiocina CX3CL1 , Interleucina-18 , Factor de Crecimiento Transformador beta1 , Factor de Crecimiento Nervioso , Neopterin/líquido cefalorraquídeo , Factor de Necrosis Tumoral alfa , Inflamasomas , Factor Neurotrófico Derivado del Encéfalo , Interleucina-6 , Receptor Activador Expresado en Células Mieloides 1 , Factor A de Crecimiento Endotelial Vascular , Biomarcadores , Inflamación , Infecciones por HTLV-I/patología

RESUMEN

Recently, it has been proposed that bruxism could represent an overlearned behavior due to the absence of corticomotor plasticity following a relevant tooth-clenching task (TCT). This study assessed the modulatory effects of a nerve growth factor (NGF) injection on masseter muscle corticomotor excitability, jaw motor performance, pain, and limitation in bruxer and control participants following a TCT. Participants characterized as definitive bruxers or controls were randomly assigned to have injected into the right masseter muscle either NGF or isotonic saline (IS), resulting in a study with 4 arms: IS_Control (n = 7), IS_Bruxer (n = 7); NGF_Control (n = 6), and NGF_Bruxer (n = 8). The primary outcome was the masseter motor evoked potential (MEP) amplitude measured at baseline and after a TCT. After the interventions, significantly higher and lower MEP amplitude and corticomotor map area were observed, respectively, in the IS_Control and NGF_Control groups (P < 0.05). Precision and accuracy depended on the series and target force level with significant between-group differences (P < 0.01). NGF-induced masseter muscle sensitization, in combination with a training-induced effect, can significantly impact the corticomotor excitability of the masseter muscle in control participants indicating substantial changes in corticomotor excitability, which are not observed in bruxers. These preliminary findings may have therapeuthic implications for the potential to "detrain" and manage bruxism, but further studies with larger sample sizes will be needed to test this new concept.

Asunto(s)

Bruxismo , Músculo Masetero , Humanos , Músculo Masetero/fisiología , Factor de Crecimiento Nervioso/farmacología , Prueba de Estudio Conceptual , Electromiografía/métodos , Potenciales Evocados Motores/fisiología , Estimulación Magnética Transcraneal

RESUMEN

BACKGROUND: Hepatic encephalopathy (HE) is a neuropsychiatric syndrome that involves cognitive and motor dysfunctions due to hepatic failure. The clinical and experimental studies suggest that the angiotensin (Ang) converting enzyme (ACE), Ang II, and angiotensin type 1 receptor (AT1R), which compose the classical pathway of the renin-angiotensin system (RAS), exacerbate neuroinflammation in different neurologic diseases. Conversely, Ang-(1-7), ACE2, and Mas receptor, which integrate the alternative RAS axis, have been shown as promising therapeutic targets in neuropsychiatric disorders, leading to neuroprotection. OBJECTIVE: This study aimed to investigate the potential participation of the RAS components in thioacetamide (TAA)-induced HE in mice. METHODS: We also evaluated the levels of neurotrophic factors, pro-inflammatory cytokines, and chemokine in the central nervous system of TAA-induced HE in mice. Mice were submitted to acute liver failure induced by TAA administration by intraperitoneal route. Measurements of RAS components (ACE, Ang II, ACE2 and Ang1-7) and neurotrophic factors (BDNF, GDNF and NGF) were obtained by ELISA assay. Pro-inflammatory cytokines (TNF, IFN-γ, IL-6, IL-12p70) and the chemokine (CCL2) were quantified by cytometric bead array. The student's t-test was applied for statistical analysis. RESULTS: Mice presented increased cortical levels of ACE, while Ang-(1-7) levels were decreased in cortical and hippocampal samples compared to controls. Moreover, HE mice had an increase in the Ang II/Ang-(1-7) ratio along with reduced levels of neural growth factor (NGF) in the prefrontal cortex. They also showed elevated levels of IFN-γ and CCL2 in the prefrontal cortex and of TNF, IL-6, IL-12, and CCL2 in the hippocampus compared with controls. CONCLUSION: This study suggested that the reduction of components of the alternative RAS axis was associated with the deleterious effects of neuroinflammation and lower neuroprotective effects of NGF during TAA-induced HE.

Asunto(s)

Encefalopatía Hepática , Fármacos Neuroprotectores , Ratones , Animales , Renina , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/uso terapéutico , Enzima Convertidora de Angiotensina 2 , Factor de Crecimiento Nervioso/metabolismo , Enfermedades Neuroinflamatorias , Interleucina-6/metabolismo , Peptidil-Dipeptidasa A/metabolismo , Angiotensina II/metabolismo , Fragmentos de Péptidos/metabolismo , Tioacetamida , Hipocampo/metabolismo , Lóbulo Frontal/metabolismo

RESUMEN

The perception of noxious environmental stimuli by nociceptive sensory neurons is an essential mechanism for the prevention of tissue damage. Etv4 is a transcriptional factor expressed in most nociceptors in dorsal root ganglia (DRG) during the embryonic development. However, its physiological role remains unclear. Here, we show that Etv4 ablation results in defects in the development of the peripheral peptidergic projections in vivo, and in deficits in axonal elongation and growth cone morphology in cultured sensory neurons in response to NGF. From a mechanistic point of view, our findings reveal that NGF regulates Etv4-dependent gene expression of molecules involved in extracellular matrix (ECM) remodeling. Etv4-null mice were less sensitive to noxious heat stimuli and chemical pain, and this behavioral phenotype correlates with a significant reduction in the expression of the pain-transducing ion channel TRPV1 in mutant mice. Together, our data demonstrate that Etv4 is required for the correct innervation and function of peptidergic sensory neurons, regulating a transcriptional program that involves molecules associated with axonal growth and pain transduction.

Asunto(s)

Factor de Crecimiento Nervioso , Nocicepción , Proteínas Proto-Oncogénicas c-ets/metabolismo , Animales , Ganglios Espinales/metabolismo , Ratones , Factor de Crecimiento Nervioso/genética , Nocicepción/fisiología , Dolor/metabolismo , Células Receptoras Sensoriales/metabolismo

RESUMEN

Genetic variations in components of the immune response seem to be an important factor that contributes to the manifestation of symptoms of some diseases related to HTLV-1 infection. Nerve growth factor (NGF) and the p75 neurotrophin receptor (p75NTR) are related to the maintenance of neurons and the activation of the immune response. In this study, we evaluated the association of the NGF -198C/T, NGF Ala35Val, and p75NTR Ser205Leu polymorphisms with HTLV-1 infection and plasma cytokine levels in 166 samples from individuals infected with HTLV-1 (59 symptomatic and 107 asymptomatic). The genotyping and quantification of the proviral load were performed by real-time PCR, and cytokine levels were measured by ELISA. The NGF -198C/T and NGF Ala35Val polymorphisms were not associated with HTLV-1 infection. The frequency of the Ser/Leu genotype of p75NTR Ser205Leu was more frequent in the control group (p = 0.0385), and the Ser/Leu genotype and allele Leu were more frequent among the asymptomatic (p < 0.05), especially with respect to the HTLV-1-associated myelopathy (HAM) group (p < 0.05). The symptomatic showed a higher proviral load and higher TNF-α and IL-10 levels (p < 0.05). Asymptomatic carriers of the Ser/Leu genotype (p = 0.0797) had lower levels of proviral load and higher levels of TNF-α (p = 0.0507). Based on the results obtained, we conclude that the p75NTR Ser205Leu polymorphism may be associated with reduced susceptibility to HTLV-1 infection, a lower risk of developing symptoms, including HAM, and better infection control.

Asunto(s)

Infecciones por HTLV-I , Virus Linfotrópico T Tipo 1 Humano , Paraparesia Espástica Tropical , Citocinas , Virus Linfotrópico T Tipo 1 Humano/genética , Humanos , Factor de Crecimiento Nervioso , Provirus/genética , Receptor de Factor de Crecimiento Nervioso , Factor de Necrosis Tumoral alfa , Carga Viral

RESUMEN

Sepsis is a life-threatening organ dysfunction, which demands notable attention for its treatment, especially in view of the involvement of immunodepressed patients, as the case of patients with diabetes mellitus (DM), who constitute a population susceptible to develop infections. Thus, considering this endocrine pathology as an implicatory role on the immune system, the aim of this study was to show the relationship between this disease and sepsis on neuroinflammatory and neurochemical parameters. Levels of IL-6, IL-10, brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), and mitochondrial respiratory chain complexes were evaluated in the hippocampus and prefrontal cortex 24 h after sepsis by cecal ligation and perforation (CLP) in Wistar rats induced to type 1 diabetes by alloxan (150 mg/kg). It was verified that diabetes implied immune function after 24 h of sepsis, since it contributed to the increase of the inflammatory process with higher production of IL-6 and decreased levels of IL-10 only in the hippocampus. In the same brain area, a several decrease in NGF level and activity of complexes I and II of the mitochondrial respiratory chain were observed. Thus, diabetes exacerbates neuroinflammation and results in mitochondrial impairment and downregulation of NGF level in the hippocampus after sepsis.

Asunto(s)

Diabetes Mellitus , Sepsis , Animales , Ratas , Ratas Wistar , Factor de Crecimiento Nervioso/metabolismo , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Enfermedades Neuroinflamatorias , Encéfalo/metabolismo , Sepsis/metabolismo , Mitocondrias/metabolismo , Modelos Animales de Enfermedad

RESUMEN

OBJECTIVE: Bladder wall thickness (BWTh) measurements and Nerve Growth Factor (NGF) /creatinine (Cr) values, as noninvasive tools, were found to predict daytime voiding problems in children with overactive bladder (OAB). The goal of this research was to examine if bladder wall thickness together with urine NGF/Cr could be a clinical utility in treatment outcome of OAB in children. PATIENTS AND METHODS: A total of 60 children with OAB, (Group 1; n=40) and healthy normal controls (Group 2; n=20), aged 6-14 years old were involved in this prospective study. Children were evaluated with detailed history and physical examination, including neurologic examination, and were asked to complete a self-reported questionnaire and a 3-day bladder diary with the aid of their parents. Uroflowmetry was performed in all cases. Urinary nerve growth factor levels were measured by the ELISA and BWTh was measured trans-abdominally by one uro-radiologist specialized in pediatric ultrasonography. Urinary NGF levels were normalized by urinary creatinine levels and compared among all subgroups. Children with OAB received urotherapy as first line treatment at least for three months. 18 children refractory to urotherapy received anticholinergic therapy defined as group 3. RESULTS: The median age of the study group was 10 (range 6 to 16). After urotherapy, 22 children had similar BWTh and NGF/Cr values compared to controls. (2.75 ± 1.15; 2.40 ± 1.00 mm; p=0.86 and 1.02 ± 0.10; 0.78 ± 0.15; p=0.12, respectively). After anticholinergic treatment, BWTh levels (2.25 ± 0.90; 2.40 ± 1.00 mm; p=0.94) and NGF/Cr values (0.95 ± 0.10; 0.78 ± 0.15; p=0.42, respectively) had no significantly difference compared to controls (Group 2). In receiver operating characteristic analysis, bladder wall thickness was found to have sensitivity of 85% and specificity of 84.2% (3,20 AUC ,913; 95 %) and NGF/Cr had sensitivity of 90% and specificity of 92.1% (1,595; AUC ,947; 95 %) in predicting treatment outcome in children with OAB. CONCLUSIONS: Bladder wall thickness measurements and NGF/Cr values, as noninvasive tools, could guide outcomes in the treatment of children with overactive bladder.

Asunto(s)

Vejiga Urinaria Hiperactiva , Adolescente , Biomarcadores/orina , Niño , Humanos , Factor de Crecimiento Nervioso/uso terapéutico , Factor de Crecimiento Nervioso/orina , Estudios Prospectivos , Resultado del Tratamiento , Vejiga Urinaria/diagnóstico por imagen , Vejiga Urinaria Hiperactiva/tratamiento farmacológico

RESUMEN

Chronic pain is a major health issue, and the search for new analgesics has become increasingly important because of the addictive properties and unwanted side effects of opioids. To explore potentially new drug targets, we investigated mutations in the NTRK1 gene found in individuals with congenital insensitivity to pain with anhidrosis (CIPA). NTRK1 encodes tropomyosin receptor kinase A (TrkA), the receptor for nerve growth factor (NGF) and that contributes to nociception. Molecular modeling and biochemical analysis identified mutations that decreased the interaction between TrkA and one of its substrates and signaling effectors, phospholipase Cγ (PLCγ). We developed a cell-permeable phosphopeptide derived from TrkA (TAT-pQYP) that bound the Src homology domain 2 (SH2) of PLCγ. In HEK-293T cells, TAT-pQYP inhibited the binding of heterologously expressed TrkA to PLCγ and decreased NGF-induced, TrkA-mediated PLCγ activation and signaling. In mice, intraplantar administration of TAT-pQYP decreased mechanical sensitivity in an inflammatory pain model, suggesting that targeting this interaction may be analgesic. The findings demonstrate a strategy to identify new targets for pain relief by analyzing the signaling pathways that are perturbed in CIPA.

Asunto(s)

Hipohidrosis , Mutación , Insensibilidad Congénita al Dolor , Fosfolipasa C gamma , Receptor trkA , Analgésicos/farmacología , Animales , Canalopatías/genética , Canalopatías/metabolismo , Células HEK293 , Humanos , Hipohidrosis/genética , Hipohidrosis/metabolismo , Ratones , Factor de Crecimiento Nervioso/genética , Factor de Crecimiento Nervioso/farmacología , Dolor/genética , Dolor/metabolismo , Insensibilidad Congénita al Dolor/genética , Insensibilidad Congénita al Dolor/metabolismo , Fosfolipasa C gamma/genética , Fosfolipasa C gamma/metabolismo , Receptor trkA/genética , Receptor trkA/metabolismo

RESUMEN

Neurodegenerative diseases are characterized by progressive loss of the structure and function of specific neuronal populations, and have been associated with reduced neurotrophic support. Neurotrophins, like NGF (nerve growth factor), are endogenous proteins that induce neuritogenesis and modulate axonal growth, branching, and synapsis; however, their therapeutic application is limited mainly by low stability, short half-life, and inability to cross the blood-brain barrier (BBB). Small neurotrophic molecules that have suitable pharmacokinetics and are able to cross the BBB are potential candidates for neuroprotection. Baccharin is a bioactive small molecule isolated from Brazilian green propolis. In the present study, we investigated the neurotrophic and neuroprotective potential of baccharin in the PC12 cell neuronal model. We used pharmacological inhibitors (K252a, LY294002, and U0126), and ELISA (phospho-trkA, phospho-Akt, and phospho-MEK) to investigate the involvement of trkA receptor, PI3k/Akt pathway, and MAPK/Erk pathway, respectively. Additionally, we evaluated the expression of axonal (GAP-43) and synaptic (synapsin I) proteins by western blot. The results showed that baccharin induces neuritogenesis in NGF-deprived PC12 cells, through activation of trkA receptor and the downstream signaling cascades (PI3K/Akt and MAPK/ERK), which is the same neurotrophic pathway activated by NGF in PC12 cells and neurons. Baccharin also induced the expression of GAP-43 and synapsin I, which mediate axonal and synaptic plasticity, respectively. Additionally, in silico predictions of baccharin showed favorable physicochemical properties, pharmacokinetics, drug-likeness, and medicinal chemistry friendliness. Altogether, these findings suggest that baccharin is a promising neurotrophic agent whose therapeutic application in neurodegeneration should be further investigated.

Asunto(s)

Factor de Crecimiento Nervioso , Própolis , Animales , Brasil , Proteína GAP-43/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Factor de Crecimiento Nervioso/farmacología , Células PC12 , Fosfatidilinositol 3-Quinasas/metabolismo , Própolis/farmacología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ratas , Receptor trkA/metabolismo , Transducción de Señal , Sinapsinas/metabolismo , Tricotecenos

RESUMEN

Nerve growth factor (NGF) and its high-affinity receptor TRKA are overexpressed in epithelial ovarian cancer (EOC) displaying a crucial role in the disease progression. Otherwise, NGF interacts with its low-affinity receptor P75, activating pro-apoptotic pathways. In neurons, P75 could be cleaved by metalloproteinases (α and γ-secretases), leading to a decrease in P75 signaling. Therefore, this study aimed to evaluate whether the shedding of P75 occurs in EOC cells and whether NGF/TRKA could promote the cleavage of the P75 receptor. The immunodetection of the α-secretase, ADAM17, TRKA, P75, and P75 fragments was assessed by immunohisto/cytochemistry and Western blot in biopsies and ovarian cell lines. The TRKA and secretases' inhibition was performed using specific inhibitors. The results show that P75 immunodetection decreased during EOC progression and was negatively correlated with the presence of TRKA in EOC biopsies. NGF/TRKA increases ADAM17 levels and the fragments of P75 in ovarian cells. This effect is abolished when cells are previously treated with ADAM17, γ-secretase, and TRKA inhibitors. These results indicate that NGF/TRKA promotes the shedding of P75, involving the activation of secretases such as ADAM17. Since ADAM17 has been proposed as a screening marker for early detection of EOC, our results contribute to understanding better the role of ADAM17 and NGF/TRKA in EOC pathogenesis, which includes the NGF/TRKA-mediated cleavage of P75.

Asunto(s)

Proteína ADAM17/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Factor de Crecimiento Nervioso/metabolismo , Neoplasias Ováricas/metabolismo , Ovario/metabolismo , Receptor trkA/metabolismo , Factores de Transcripción/metabolismo , Carcinoma Epitelial de Ovario/metabolismo , Carcinoma Epitelial de Ovario/patología , Línea Celular , Línea Celular Tumoral , Femenino , Humanos , Persona de Mediana Edad , Neuronas/metabolismo , Neoplasias Ováricas/patología , Ovario/patología , Transducción de Señal/fisiología

RESUMEN

PURPOSE: Colorectal cancer (CRC) is one most cancer type of high incidence and high mortality rate. Metastasis play an important role in survival rate and life quality of colorectal cancer patients. Nerve growth factor (NGF) has been shown to be involved in the metastasis and deterioration in many cancers, but the detail mechanisms in promoting the metastasis of colorectal cancer remain unknown. In this study, we aimed to explore the mechanism of NGF promoting colorectal cancer metastasis to provide new insights for developing NGF anti-colorectal cancer drugs. METHODS: We examined the expression of NGF in human colorectal cancer by immunohistochemical staining, and Western blot to evaluate the relationship between NGF and colorectal cancer metastasis. Using biochemical experiments including wound healing assay, transwell migration and invasion assay, RT-PCR, Western blot and ELISA to explore the relative mechanism of NGF promoting colorectal cancer cells metastasis in vivo. RESULTS: Our results found that the high expression of NGF was related with high incidence of metastasis. The binding of NGF to TrkA phosphorylated TrkA, which activated MAPK/Erk signaling pathway increasing the expression NGAL to enhance the activity of MMP2 and MMP9, promoted colorectal cancer metastasis. CONCLUSION: Our finding demonstrated that NGF increased NGAL expression to enhance MMPs activity to promoted colorectal cancer cell metastasis by TrkA-MAPK/Erk axis.

Asunto(s)

Neoplasias Colorrectales/patología , Lipocalina 2/fisiología , Metaloproteinasas de la Matriz/fisiología , Factor de Crecimiento Nervioso/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia