RESUMO
Prematurity has physical consequences, such as lower birth weight, decreased muscle mass and increased risk of adult-onset metabolic disease. Insulin-like growth factor 1 (IGF-1) has therapeutic potential to improve the growth and quality of muscle and tendon in premature births, and thus attenuate some of these sequalae. We investigated the effect of IGF-1 on extensor carpi radialis muscle and biceps brachii tendon of preterm piglets. The preterm group consisted of 19-day-old preterm (10 days early) piglets, treated with either IGF-1 or vehicle. Term controls consisted of groups of 9-day-old piglets (D9) and 19-day-old piglets (D19). Muscle samples were analysed by immunofluorescence to determine the cross-sectional area (CSA) of muscle fibres, fibre type composition, satellite cell content and central nuclei-containing fibres in the muscle. Tendon samples were analysed for CSA, collagen content and maturation, and vascularization. Gene expression of the tendon was measured by RT-qPCR. Across all endpoints, we found no significant effect of IGF-1 treatment on preterm piglets. Preterm piglets had smaller muscle fibre CSA compared to D9 and D19 control group. Satellite cell content was similar across all groups. For tendon, we found an effect of age on tendon CSA, and mRNA levels of COL1A1, tenomodulin and scleraxis. Immunoreactivity for elastin and CD31, and several markers of tendon maturation, were increased in D9 compared to the preterm piglets. Collagen content was similar across groups. IGF-1 treatment of preterm-born piglets does not influence the growth and maturation of skeletal muscle and tendon.
RESUMO
Newborns exposed to birth asphyxia transiently experience deficient blood flow and a lack of oxygen, potentially inducing hypoxic-ischaemic encephalopathy and subsequent neurological damage. Immunomodulatory components in plasma may dampen these responses. Using caesarean-delivered pigs as a model, we hypothesized that dietary plasma supplementation improves brain outcomes in pigs exposed to birth asphyxia. Mild birth asphyxia was induced by temporary occlusion of the umbilical cord prior to caesarean delivery. Motor development was assessed in asphyxiated (ASP) and control (CON) piglets using neonatal arousal, physical activity and gait test parameters before euthanasia on Day 4. The ASP pigs exhibited increased plasma lactate at birth, deficient motor skills and increased glial fibrillary acidic protein levels in CSF and astrogliosis in the putamen. The expression of genes related to oxidative stress, inflammation and synaptic functions was transiently altered in the motor cortex and caudate nucleus. The number of apoptotic cells among CTIP2-positive neurons in the motor cortex and striatal medium spiny neurons was increased, and maturation of preoligodendrocytes in the internal capsule was delayed. Plasma supplementation improved gait performance in the beam test, attenuated neuronal apoptosis and affected gene expression related to neuroinflammation, neurotransmission and antioxidants (motor cortex, caudate). We present a new clinically relevant animal model of moderate birth asphyxia inducing structural and functional brain damage. The components in plasma that support brain repair remain to be identified but may represent a therapeutic potential for infants and animals after birth asphyxia.
Assuntos
Animais Recém-Nascidos , Asfixia Neonatal , Encéfalo , Modelos Animais de Doenças , Animais , Suínos , Asfixia Neonatal/terapia , Encéfalo/metabolismo , Feminino , Estresse Oxidativo/fisiologia , Hipóxia-Isquemia Encefálica/terapia , Hipóxia-Isquemia Encefálica/metabolismo , Neurônios/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Asfixia/terapia , Gravidez , Córtex Motor/metabolismoRESUMO
BACKGROUND: Reduced insulin-like growth factor-1 (IGF-1) levels may contribute to impaired organ development in preterm infants. Using preterm pigs as a model, we hypothesized that IGF-1 supplementation improves health and gut development during the first three weeks of life. METHODS: First, clinical and organ endpoints were compared between artificially-reared, cesarean-delivered preterm pigs and vaginally-delivered, sow-reared term pigs at 5, 9 and 19 days. Next, preterm pigs were treated with recombinant human IGF-1 for 19 days (2.25 mg/kg/day, systemically). RESULTS: Relative to term pigs, preterm pigs had lower body weight, fat, bone contents, relative weights of liver and spleen and a longer and thinner intestine at 19 days. Preterm birth reduced intestinal villi heights and peptidase activities, but only at 5 and 9 days. In preterm pigs, IGF-1 reduced mortality primarily occurring from gastrointestinal complications and with a tendency towards salvaging smaller pigs. IGF-1 supplementation also increased spleen and kidney weights, small intestine length and maltase to lactase activity, reflecting gut maturation. CONCLUSION: Preterm birth affects body composition and gut maturation in the first 1-2 weeks, but differences are marginal thereafter. Supplemental IGF-1 may improve gut health in pigs and infants in the first few weeks after preterm birth. IMPACT: Insulin-like growth factor 1 (IGF-1) supplementation may improve gut health and development in prematurity, but whether the effects are sustained beyond the immediate postnatal period is unclear. In preterm pigs, the prematurity effects on IGF-1 and gut health deficiencies are most pronounced during the first week of life and diminishes thereafter. In preterm pigs, IGF-1 supplementation beyond the first week of life reduced mortality. The present study provides evidence of a sustained effect of IGF-1 supplementation on the gastrointestinal tract after the immediate postnatal period.
RESUMO
Introduction: Preterm infants have increased risk of impaired neurodevelopment to which reduced systemic levels of insulin-like growth factor 1 (IGF-1) in the weeks after birth may play a role. Hence, we hypothesized that postnatal IGF-1 supplementation would improve brain development in preterm pigs, used as a model for preterm infants. Methods: Preterm pigs delivered by cesarean section received recombinant human IGF-1/IGF binding protein-3 complex (rhIGF-1/rhIGFBP-3, 2.25 mg/kg/day) or vehicle from birth to postnatal day 19. Motor function and cognition were assessed by monitoring of in-cage and open field activities, balance beam test, gait parameters, novel object recognition and operant conditioning tests. Collected brains were subject to magnetic resonance imaging (MRI), immunohistochemistry, gene expression analyses and protein synthesis measurements. Results: The IGF-1 treatment increased cerebellar protein synthesis rates (both in vivo and ex vivo). Performance in the balance beam test was improved by IGF-1 but not in other neurofunctional tests. The treatment decreased total and relative caudate nucleus weights, without any effects to total brain weight or grey/white matter volumes. Supplementation with IGF-1 reduced myelination in caudate nucleus, cerebellum, and white matter regions and decreased hilar synapse formation, without effects to oligodendrocyte maturation or neuron differentiation. Gene expression analyses indicated enhanced maturation of the GABAergic system in the caudate nucleus (decreased NKCC1:KCC2 ratio) with limited effects in cerebellum or hippocampus. Conclusion: Supplemental IGF-1 during the first three weeks after preterm birth may support motor function by enhancing GABAergic maturation in the caudate nucleus, despite reduced myelination. Supplemental IGF-1 may support postnatal brain development in preterm infants, but more studies are required to identify optimal treatment regimens for subgroups of very or extremely preterm infants.
RESUMO
Very preterm infants show low levels of insulin-like growth factor-1 (IGF-1), which is associated with postnatal growth restriction and poor neurologic outcomes. It remains unknown whether supplemental IGF-1 may stimulate neurodevelopment in preterm neonates. Using cesarean-delivered preterm pigs as a model of preterm infants, we investigated the effects of supplemental IGF-1 on motor function and on regional and cellular brain development. Pigs were treated with 2.25 mg/kg/d recombinant human IGF-1/IGF binding protein-3 complex from birth until day 5 or 9 before the collection of brain samples for quantitative immunohistochemistry (IHC), RNA sequencing, and quantitative PCR analyses. Brain protein synthesis was measured using in vivo labeling with [2H5] phenylalanine. We showed that the IGF-1 receptor was widely distributed in the brain and largely coexisted with immature neurons. Region-specific quantification of IHC labeling showed that IGF-1 treatment promoted neuronal differentiation, increased subcortical myelination, and attenuated synaptogenesis in a region-dependent and time-dependent manner. The expression levels of genes involved in neuronal and oligodendrocyte maturation, and angiogenic and transport functions were altered, reflecting enhanced brain maturation in response to IGF-1 treatment. Cerebellar protein synthesis was increased by 19% at day 5 and 14% at day 9 after IGF-1 treatment. Treatment had no effect on Iba1+ microglia or regional brain weights and did not affect motor development or the expression of genes related to IGF-1 signaling. In conclusion, the data show that supplemental IGF-1 promotes brain maturation in newborn preterm pigs. The results provide further support for IGF-1 supplementation therapy in the early postnatal period in preterm infants.
Assuntos
Recém-Nascido Prematuro , Fator de Crescimento Insulin-Like I , Gravidez , Feminino , Animais , Suínos , Recém-Nascido , Humanos , Fator de Crescimento Insulin-Like I/farmacologia , Fator de Crescimento Insulin-Like I/metabolismo , Encéfalo/metabolismo , Cerebelo/metabolismo , Suplementos NutricionaisRESUMO
A challenge in neurology is the lack of efficient brain-penetrable neuroprotectants targeting multiple disease mechanisms. Plasmonic gold nanostars are promising candidates to deliver standard-of-care drugs inside the brain but have not been trialed as carriers for neuroprotectants. Here, we conjugated custom-made peptide dendrimers (termed H3/H6), encompassing motifs of the neurotrophic S100A4-protein, onto star-shaped and spherical gold nanostructures (H3/H6-AuNS/AuNP) and evaluated their potential as neuroprotectants and interaction with neurons. The H3/H6 nanostructures crossed a model blood-brain barrier, bound to plasma membranes, and induced neuritogenesis with the AuNS, showing higher potency/efficacy than the AuNP. The H3-AuNS/NP protected neurons against oxidative stress, the H3-AuNS being more potent, and against Parkinson's or Alzheimer's disease (PD/AD)-related cytotoxicity. Unconjugated S100A4 motifs also decreased amyloid beta-induced neurodegeneration, introducing S100A4 as a player in AD. Using custom-made dendrimers coupled to star-shaped nanoparticles is a promising route to activate multiple neuroprotective pathways and increase drug potency to treat neurodegenerative disorders.
Assuntos
Doença de Alzheimer , Dendrímeros , Fármacos Neuroprotetores , Humanos , Fármacos Neuroprotetores/química , Peptídeos beta-Amiloides , Dendrímeros/farmacologia , Dendrímeros/uso terapêutico , Neurônios , Ouro/química , Doença de Alzheimer/tratamento farmacológicoRESUMO
Alzheimer's disease (AD) is a progressive and irreversible neurodegenerative disease characterized by the accumulation of aggregated amyloid beta (Aß) and hyperphosphorylated tau along with a slow decline in cognitive functions. Unlike advanced AD, the initial steps of AD pathophysiology have been poorly investigated, partially due to limited availability of animal models focused on the early, plaque-free stages of the disease. The aim of this study was to evaluate the early behavioral, anatomical and molecular alterations in wild-type rats following intracerebroventricular injections of human Aß oligomers (AßOs). Bioactive human AD and nondemented control brain tissue extracts were characterized using ELISA and proteomics approaches. Following a bilateral infusion, rats underwent behavioral testing, including the elevated plus maze, social recognition test, Morris water maze and Y-maze within 6 weeks postinjection. An analysis of brain structure was performed with manganese-enhanced MRI. Collected brain tissues were analyzed using stereology, immunohistochemistry, ELISA and qPCR. No sensorimotor deficits affecting motor performance on different maze tasks were observed, nor was spatial memory disturbed in AD rats. In contrast, a significant impairment of social memory became evident at 21 days postinjection. This deficit was associated with a significantly decreased volume of the lateral entorhinal cortex and a tendency toward a decrease in the total brain volume. Significant increase of cleaved caspase-3-positive cells, microglial activation and proinflammatory responses accompanied by altered expression of synaptic markers were observed in the hippocampus of AD rats with immunohistochemical and qPCR approaches at 6 weeks postinjection. Our data suggest that the social memory impairment observed in AßO-injected rats might be determined by neuroinflammatory responses and synaptopathy. An infusion of native oligomeric Aß in the rat brain represents a feasible tool to model early plaque-free events associated with AD.
Assuntos
Doença de Alzheimer , Doenças Neurodegenerativas , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Modelos Animais de Doenças , Hipocampo/metabolismo , Humanos , Aprendizagem em Labirinto/fisiologia , Doenças Neurodegenerativas/metabolismo , Placa Amiloide/metabolismo , RatosRESUMO
Infants with neonatal cholestasis are prone to neurodevelopmental deficits, however, the underlying pathogenesis is unclear. Lipid malabsorption and accumulation of potentially neurotoxic molecules in the blood such as bile acids are important yet relatively unexplored pathways. Here, we developed a translational piglet model to understand how the molecular bile acid and lipid composition of the brain is affected by this disease and relates to motor function. Piglets (8-days old) had bile duct ligation or sham surgery and were fed a formula diet for 3 weeks. Alongside sensory-motor deficits observed in bile duct-ligated animals, we found a shift toward a more hydrophilic and conjugated bile acid profile in the brain. Additionally, comprehensive lipidomics of the cerebellum revealed a decrease in total lipids including phosphatidylinositols and phosphatidylserines and increases in lysophospholipid species. This was paralleled by elevated cerebellar expression of genes related to inflammation and tissue damage albeit without significant impact on the brain transcriptome. This study offers new insights into the developing brain's molecular response to neonatal cholestasis indicating that bile acids and lipids may contribute in mediating motor deficits.
Assuntos
Ácidos e Sais Biliares , Colestase , Animais , Ductos Biliares/metabolismo , Encéfalo/metabolismo , Colestase/metabolismo , Humanos , Lipídeos , SuínosRESUMO
Newborn infants are prone to sepsis and related inflammation of different organs. Neuroinflammation has been associated with long-term adverse neuronal (neuropsychiatric/neurodegenerative) outcomes, including attention deficit hyperactivity disorder (ADHD) or even Alzheimer's disease. Despite a vast number of findings on sepsis-induced inflammatory responses in the central nervous system (CNS), how neuroinflammation affects brain development remains largely elusive. In this study, neonates with clinical sepsis and screened for meningitis were included and classified by the neuroinflammation status based on cerebrospinal fluid (CSF) parameters (INF vs. NOINF). CSF samples collected from clinical screening were subjected to proteomics analysis. Proteins with differential abundance were subjected to enrichment analysis to reveal affected biological pathways. INF and NOINF infants had similar demographic data and hematological and biochemical parameters in blood and CSF. The CSF proteomes were essentially different between the two groups. All 65 proteins with differential abundance showed lower abundance in the INF group and functionally covered pivotal developmental processes, including axonal and synaptic function and extracellular homeostasis. CSF proteins, PTPRZ1 and IGFBP4, were correlated with C-reactive protein (CRP) and ratios of immature/total neutrophils in blood. In general, a substantial change in the CSF protein profile was found under neuroinflammation, and these changes are related to systemic conditions. The results suggest that changes in CSF proteins may be involved in sepsis-affected neurodevelopment, such as disturbances in circuit formation, which has the potential to predispose neonates to long-term adverse outcomes.
RESUMO
Breast milk has neurodevelopmental advantages compared to infant formula, especially in low-birth-weight infants, which may in part relate to the fat source. This study compared neurodevelopmental outcomes in three-day-old normal birth weight (NBW) and intrauterine growth restricted (IUGR) piglets fed a formula diet with either vegetable oil (VEG) or bovine milk fat sources (MILK) for three weeks in a 2 × 2 factorial design. Behavioural tests, lipidomics, MRI and RNA sequencing analyses of plasma and brain tissue were conducted. The absolute levels of 82% and 11% of lipid molecules were different between dietary groups in plasma and hippocampus, respectively. Of the lipid molecules with differential abundance in the hippocampus, the majority were upregulated in MILK versus VEG, and they mainly belonged to the group of glycerophospholipids. Lower absolute brain weights, absolute grey and white matter volumes and behaviour and motor function scores, and higher relative total brain weights were present in IUGR compared to NBW with minor influence of diet. Cognitive function and cerebellar gene expression profiles were similar for dietary and weight groups, and overall only minor interactive effects between diet and birth weight were observed. Overall, we show that the dietary fat source influences the plasma and to a lesser degree the hippocampal lipidome and is unable to improve on IUGR-induced brain structural and functional impairments.
Assuntos
Lipidômica , Verduras , Animais , Peso ao Nascer , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Dieta , Gorduras na Dieta , Retardo do Crescimento Fetal/metabolismo , Humanos , SuínosRESUMO
Chorioamnionitis (CA) is a risk factor for preterm birth and is associated with neurodevelopmental delay and cognitive disorders. Prenatal inflammation-induced brain injury may resolve during the immediate postnatal period when rapid brain remodeling occurs. Cerebrospinal fluid (CSF) collected at birth may be a critical source of predictive biomarkers. Using pigs as a model of preterm infants exposed to CA, we hypothesized that prenatal lipopolysaccharide (LPS) exposure induces proteome changes in the CSF and brain at birth and postnatally. Fetal piglets (103 days gestation of full-term at 117 days) were administered intra-amniotic (IA) lipopolysaccharide (LPS) 3 days before preterm delivery by caesarian section. CSF and brain tissue were collected on postnatal Days 1 and 5 (P1 and P5). CSF and hippocampal proteins were profiled by LC-MS-based quantitative proteomics. Neuroinflammatory responses in the cerebral cortex, periventricular white matter and hippocampus were evaluated by immunohistochemistry, and gene expression was evaluated by qPCR. Pigs exposed to LPS in utero showed changes in CSF protein levels at birth but not at P5. Complement protein C3, hemopexin, vasoactive intestinal peptide, carboxypeptidase N subunit 2, ITIH1, and plasminogen expression were upregulated in the CSF, while proteins associated with axon growth and synaptic functions (FGFR1, BASP1, HSPD1, UBER2N, and RCN2), adhesion (talin1), and neuronal survival (Atox1) were downregulated. Microglia, but not astrocytes, were activated by LPS at P5 in the hippocampus but not in other brain regions. At this time, marginal increases in complement protein C3, LBP, HIF1a, Basp1, Minpp1, and FGFR1 transcription indicated hippocampal proinflammatory responses. In conclusion, few days exposure to endotoxin prenatally induce proteome changes in the CSF and brain at birth, but most changes resolve a few days later. The developing hippocampus has high neuronal plasticity in response to perinatal inflammation. Changes in CSF protein expression at birth may predict later structural brain damage in preterm infants exposed to variable types and durations of CA-related inflammation in utero.
Assuntos
Lesões Encefálicas , Corioamnionite , Nascimento Prematuro , Animais , Encéfalo , Lesões Encefálicas/complicações , Proteínas de Ligação ao Cálcio , Corioamnionite/induzido quimicamente , Proteínas do Sistema Complemento/efeitos adversos , Proteínas de Transporte de Cobre , Endotoxinas/toxicidade , Feminino , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Inflamação , Lipopolissacarídeos/farmacologia , Chaperonas Moleculares , Gravidez , Proteoma , Proteômica , SuínosRESUMO
Insight into the bidirectional signaling between primary human myogenic cells and neurons is lacking. For this purpose, human myogenic cells were derived from the semitendinosus and gracilis muscles of five healthy individuals and co-cultured with cerebellar granule neurons from two litters of 7-day-old Wistar rat pups, in muscle medium or neural medium, alongside monocultures of myogenic cells or neurons. RT-PCR was performed to determine human mRNA levels of GAPDH, Ki67, myogenin, and MUSK, and the acetylcholine receptor subtypes CHRNA1, CHRNB1, CHRNG, CHRND, and CHRNE, and rat mRNA levels of GAPDH, Fth1, Rack1, vimentin, Cdh13, and Ppp1r1a. Immunocytochemistry was used to evaluate neurite outgrowth (GAP43) in the presence and absence of myogenic cells. Co-culture with primary neurons lead to higher myogenic cell gene expression levels of GAPDH, myogenin, MUSK, CHRNA1, CHRNG, and CHRND, compared to myogenic cells cultured alone. It appeared that neurons preferentially attached to myotubes and that neurite outgrowth was enhanced when neurons were cultured with myogenic cells compared to monoculture. In neural medium, rat mRNA levels of GAPDH, vimentin, Cdh13, and Ppp1r1a were greater in co-culture, versus monoculture, whereas in muscle medium co-culture lead to lower levels of Fth1, Rack1, vimentin, and Cdh13 than monoculture. These findings demonstrate mutually beneficial stimulatory signaling between rat cerebellar granule neurons and human myogenic cells, providing support for an active role for both the neuron and the muscle cell in stimulating neurite growth and myogenesis. Bidirectional muscle nerve signaling.
Assuntos
Comunicação Celular , Mioblastos/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Transdução de Sinais , Adolescente , Adulto , Animais , Células Cultivadas , Cerebelo/citologia , Técnicas de Cocultura/métodos , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/genética , Gliceraldeído-3-Fosfato Desidrogenase (Fosforiladora)/metabolismo , Humanos , Antígeno Ki-67/genética , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Mioblastos/citologia , Miogenina/genética , Miogenina/metabolismo , Crescimento Neuronal , Ratos , Ratos Wistar , Receptores Colinérgicos/genética , Receptores Colinérgicos/metabolismo , Vimentina/genética , Vimentina/metabolismoRESUMO
Skeletal muscle is an endocrine organ secreting exercise-induced factors (exerkines), which play a pivotal role in interorgan cross talk. Using mass spectrometry (MS)-based proteomics, we characterized the secretome and identified thymosin ß4 (TMSB4X) as the most upregulated secreted protein in the media of contracting C2C12 myotubes. TMSB4X was also acutely increased in the plasma of exercising humans irrespective of the insulin resistance condition or exercise mode. Treatment of mice with TMSB4X did not ameliorate the metabolic disruptions associated with diet induced-obesity, nor did it enhance muscle regeneration in vivo. However, TMSB4X increased osteoblast proliferation and neurite outgrowth, consistent with its WADA classification as a prohibited growth factor. Therefore, we report TMSB4X as a human exerkine with a potential role in cellular cross talk.
Assuntos
Proliferação de Células/efeitos dos fármacos , Contração Muscular , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Crescimento Neuronal/efeitos dos fármacos , Osteoblastos/efeitos dos fármacos , Timosina/metabolismo , Timosina/farmacologia , Animais , Estudos de Casos e Controles , Linhagem Celular Tumoral , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Modelos Animais de Doenças , Humanos , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Músculo Esquelético/fisiopatologia , Doenças Musculares/metabolismo , Doenças Musculares/patologia , Doenças Musculares/fisiopatologia , Osteoblastos/patologia , Resistência Física , Proteômica , Transdução de Sinais , Espectrometria de Massas em TandemRESUMO
Gene therapy to treat pharmacoresistant temporal lobe epilepsy in humans is now being developed using an AAV vector (CG01) that encodes the combination of neuropeptide Y and its antiepileptic receptor Y2. With this in mind, the present study aimed to provide important preclinical data on the effects of CG01 on the duration of transgene expression, cellular tropism, and potential side effects on body weight and cognitive function. The CG01 vector was administered unilaterally into the dorsal and ventral hippocampus of adult male rats and expression of both transgenes was found to remain elevated without a sign of decline at 6 months post-injection. CG01 appeared to mediate expression selectively in hippocampal neurons, without expression in astrocytes or oligodendrocytes. No effects were seen on body weight as well as on short- or long-term memory as revealed by testing in the Y-maze or Morris water maze tests. Thus these data show that unilateral CG01 vector treatment as future gene therapy in pharmacoresistant temporal lobe epilepsy patients should result in stable and long-term expression predominantly in neurons and be well tolerated without side effects on body weight and cognitive function.
RESUMO
Amyotrophic lateral sclerosis (ALS) is a devastating incurable neurological disorder characterized by motor neuron (MN) death and muscle dysfunction leading to mean survival time after diagnosis of only 2-5 years. A potential ALS treatment is to delay the loss of MNs and disease progression by the delivery of trophic factors. Previously, we demonstrated that implanted mesoporous silica nanoparticles (MSPs) loaded with trophic factor peptide mimetics support survival and induce differentiation of co-implanted embryonic stem cell (ESC)-derived MNs. Here, we investigate whether MSP loaded with peptide mimetics of ciliary neurotrophic factor (Cintrofin), glial-derived neurotrophic factor (Gliafin), and vascular endothelial growth factor (Vefin1) injected into the cervical spinal cord of mutant SOD1 mice affect disease progression and extend survival. We also transplanted boundary cap neural crest stem cells (bNCSCs) which have been shown previously to have a positive effect on MN survival in vitro and in vivo. We show that mimetic-loaded MSPs and bNCSCs significantly delay disease progression and increase survival of mutant SOD1 mice, and also that empty particles significantly improve the condition of ALS mice. Our results suggest that intraspinal delivery of MSPs is a potential therapeutic approach for the treatment of ALS.
Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Esclerose Lateral Amiotrófica/patologia , Sobrevivência Celular/efeitos dos fármacos , Dióxido de Silício/farmacologia , Esclerose Lateral Amiotrófica/metabolismo , Animais , Células Cultivadas , Medula Cervical/efeitos dos fármacos , Medula Cervical/metabolismo , Medula Cervical/patologia , Modelos Animais de Doenças , Progressão da Doença , Células-Tronco Embrionárias/efeitos dos fármacos , Células-Tronco Embrionárias/metabolismo , Células-Tronco Embrionárias/patologia , Feminino , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Camundongos , Neurônios Motores/efeitos dos fármacos , Neurônios Motores/metabolismo , Neurônios Motores/patologia , Crista Neural/efeitos dos fármacos , Crista Neural/metabolismo , Crista Neural/patologia , Células-Tronco Neurais/efeitos dos fármacos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Superóxido Dismutase/metabolismo , Superóxido Dismutase-1/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
Vascular endothelial growth factor B (VEGFB) is a pleiotropic trophic factor, which in contrast to the closely related VEGFA is known to have a limited effect on angiogenesis. VEGFB improves survival in various tissues including the nervous system, where the effect was observed mainly for peripheral neurons. The neurotrophic effect of VEGFB on central nervous system neurons has been less investigated. Here we demonstrated that VEGFB promotes neurite outgrowth from primary cerebellar granule, hippocampal, and retinal neurons in vitro. VEGFB protected hippocampal and retinal neurons from both oxidative stress and glutamate-induced neuronal death. The VEGF receptor 1 (VEGFR1) is required for VEGFB-induced neurotrophic and neuroprotective effects. Using a structure-based approach, we designed short peptides, termed Vefin1-7, mimicking the binding interface of VEGFB to VEGFR1. Vefins were analyzed for their secondary structure and binding to VEGF receptors and compared with previously described peptides derived from VEGFA, another ligand of VEGFR1. We show that Vefins have neurotrophic and neuroprotective effects on primary hippocampal, cerebellar granule, and retinal neurons in vitro with potencies comparable to VEGFB. Similar to VEGFB, Vefins were not mitogenic for MCF-7 cancer cells. Furthermore, one of the peptides, Vefin7, even dose-dependently inhibited the proliferation of MCF-7 cells in vitro. Unraveling the neurotrophic and neuroprotective potentials of VEGFB, the only nonangiogenic factor of the VEGF family, is promising for the development of neuroprotective peptide-based therapies.
Assuntos
Fator B de Crescimento do Endotélio Vascular , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Sistema Nervoso Central , Neurônios , Peptídeos/farmacologiaRESUMO
Background: Neonatal infection and sepsis are common for preterm infants due to their immature immune system. Early diagnosis is important for effective treatment, but few early markers of systemic and neuro-inflammatory responses in neonates are known. We hypothesised that systemic infection with Staphylococcus epidermidis (SE), a Gram-positive bacteria, induces acute changes to proteins in the plasma and cerebrospinal fluid (CSF), potentially affecting the immature brain of preterm neonates. Methods: Using preterm pigs as a model for preterm infants, plasma and CSF samples were collected up to 24 h after SE infection and investigated by untargeted mass spectrometry (MS)-based proteomics. Multiple differentially expressed proteins were further studied in vitro. Results: The clinical signs of sepsis and neuroinflammation in SE-infected piglets were associated with changes of multiple CSF and plasma proteins. Eight plasma proteins, including APOA4, haptoglobin, MBL1, vWF, LBP, and sCD14, were affected 6 h after infection. Acute phase reactants, including complement components, showed a time-dependent activation pattern after infection. Feeding bovine colostrum reduced the sepsis-related changes in clinical indices and plasma proteins. Neuroinflammation-related neuropeptide Y (NPY), IL-18, and MMP-14 showed distinct changes in the CSF and several brain regions (the prefrontal cortex, PVWM, and hippocampus) 24 h after infection. These changes were verified in TLR2 agonist-challenged primary microglia cells, where exogenous NPY suppressed the inflammatory response. Conclusion: Systemic infection with SE induces inflammation with rapid proteome changes in the plasma and CSF in preterm newborn pigs. The observed early markers of sepsis and neuroinflammation in preterm pigs may serve as novel biomarkers for sepsis in preterm infants.
Assuntos
Proteínas Sanguíneas/análise , Neuropeptídeo Y/líquido cefalorraquidiano , Proteoma , Sepse/imunologia , Infecções Estafilocócicas/imunologia , Staphylococcus epidermidis , Proteínas de Fase Aguda/análise , Proteínas de Fase Aguda/líquido cefalorraquidiano , Animais , Animais Recém-Nascidos , Células Cultivadas , Feminino , Interleucina-18/líquido cefalorraquidiano , Metaloproteinase 14 da Matriz/líquido cefalorraquidiano , Infecções Estafilocócicas/metabolismo , SuínosRESUMO
In the present study, we developed an in vitro model of Huntington disease (HD) by transfecting primary rat hippocampal neurons with plasmids coding for m-htt exon 1 with different number of CAG repeats (18, 50 and 115) and demonstrated the influence of the length of polyQ sequence on neurite elongation. We found that exogenously applied FGF2 significantly rescued the m-htt-induced loss of neurite outgrowth. Moreover, the Enreptin peptide, an FGFR1 and NCAM dual agonist, had a similar neuritogenic effect to FGF2 in clinically relevant m-htt 50Q-expressing neurons. This study has developed an in vitro model of primary hippocampal neurons transfected with m-htt-coding vectors that is a powerful tool to study m-htt-related effects on neuronal placticity.
Assuntos
Fator 2 de Crescimento de Fibroblastos/farmacologia , Hipocampo/efeitos dos fármacos , Proteína Huntingtina/metabolismo , Moléculas de Adesão de Célula Nervosa/farmacologia , Crescimento Neuronal/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Oligopeptídeos/farmacologia , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos , Animais , Modelos Animais de Doenças , Proteína Huntingtina/genética , Moléculas de Adesão de Célula Nervosa/agonistas , Ratos , Receptor Tipo 1 de Fator de Crescimento de Fibroblastos/agonistas , Proteínas RecombinantesRESUMO
Neurodegenerative disorders such as Alzheimer's disease (AD) are characterized by the irreversible neuronal loss and memory impairment, and current treatments are merely symptomatic. Erythropoietin (EPO) has been shown to possess neurotrophic, neuroprotective, anti-inflammatory, and memory-enhancing effects, which could be therapeutically beneficial in the different aspects of AD. However, the hematopoietic effect of EPO has hampered its potential as a neuroprotective and procognitive agent. In this study, we characterized a novel small peptide, NL100, derived from a conserved C-helix region of EPO. NL100 was shown to bind to the EPO receptor, induce neuritogenesis, and protect hippocampal neurons from oxidative- and Aß25-35-induced neurodegeneration in vitro. Importantly, long-term NL100 treatment did not induce hematopoiesis, overcoming this challenge associated with EPO. Memory-enhancing effects were demonstrated after NL100 treatment in social recognition test for short-term memory, in both healthy rats and rats challenged centrally with Aß25-35 peptide, and in the Morris water maze test for spatial memory. Moreover, NL100 was shown to reverse Aß25-35-induced hippocampal degeneration and gliosis as well as pilocarpine-induced suppression of long-term potentiation in rats. In conclusion, NL100 is a novel EPO-derived nonhematopoietic peptide with neuroprotective and memory-enhancing effects and could therefore be a potential candidate for the development of new treatments for neurodegenerative disorders and dementia.