RESUMEN
OBJECTIVES: To study the protective effect of melatonin (Mel) against oxygen-induced retinopathy (OIR) in neonatal mice and the role of the HMGB1/NF-κB/NLRP3 axis. METHODS: Neonatal C57BL/6J mice, aged 7 days, were randomly divided into a control group, a model group (OIR group), and a Mel treatment group (OIR+Mel group), with 9 mice in each group. The hyperoxia induction method was used to establish a model of OIR. Hematoxylin and eosin staining and retinal flat-mount preparation were used to observe retinal structure and neovascularization. Immunofluorescent staining was used to measure the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis and lymphocyte antigen 6G. Colorimetry was used to measure the activity of myeloperoxidase. RESULTS: The OIR group had destruction of retinal structure with a large perfusion-free area and neovascularization, while the OIR+Mel group had improvement in destruction of retinal structure with reductions in neovascularization and perfusion-free area. Compared with the control group, the OIR group had significant increases in the expression of proteins and inflammatory factors associated with the HMGB1/NF-κB/NLRP3 axis, the expression of lymphocyte antigen 6G, and the activity of myeloperoxidase (P<0.05). Compared with the OIR group, the OIR+Mel group had significant reductions in the above indices (P<0.05). Compared with the control group, the OIR group had significant reductions in the expression of melatonin receptors in the retina (P<0.05). Compared with the OIR group, the OIR+Mel group had significant increases in the expression of melatonin receptors (P<0.05). CONCLUSIONS: Mel can alleviate OIR-induced retinal damage in neonatal mice by inhibiting the HMGB1/NF-κB/NLRP3 axis and may exert an effect through the melatonin receptor pathway.
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Proteína HMGB1 , Melatonina , Enfermedades de la Retina , Animales , Ratones , Melatonina/farmacología , Melatonina/uso terapéutico , Ratones Endogámicos C57BL , FN-kappa B , Proteína con Dominio Pirina 3 de la Familia NLR , Oxígeno/efectos adversos , Peroxidasa , Receptores de Melatonina , Enfermedades de la Retina/inducido químicamente , Enfermedades de la Retina/tratamiento farmacológicoRESUMEN
Adenosine deaminase acting on RNA (ADAR) enzyme-mediated A-to-I RNA editing is widely distributed in the transcriptome. It plays an important role in autoimmune surveillance, tumorigenesis, and development. Recently, several site-directed RNA editing (SDRE) systems have been developed to target disease causative point mutations by flexibly exploiting the catalytic adenosine deamination properties of ADARs. This is based on the fact that A-to-I RNA editing is essentially an adenosine-guanine transition. In contrast to genome editing, RNA editing is tunable and transient, and there are still some shortcomings that need to be addressed. Here, we outline several SDRE systems that rely on the catalytic deamination activity of endogenous or exogenous ADARs, attempting to illustrate their strategies and discuss numerous shortcomings that need to be overcome in the future.
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Edición de ARN , Proteínas de Unión al ARN , Proteínas de Unión al ARN/genética , Adenosina/genéticaRESUMEN
BACKGROUND: The behavioral characteristics of children with autism spectrum disorder (ASD) are not only affected by their disease, but also by their parenting environment. HR-ASD has the risk of developing internalization and externalization problems. How the early development of these behavioral problems is affected by parent-child interaction is worth exploring. We tested whether parent-child interactions and parenting characteristics were associated with behavioural problems during the infant periods. METHODS: This study collected data from 91 infants at high risk for ASD and 68 matched typically developing (TD) infants, about their internalizing and externalizing behavioural problems and engagement states (i.e. positive, negative, and parent-child interactions), using free play paradigm. Parent measures were assessed using the Broad Autism Phenotypic Questionnaire (BAPQ) and Parenting Stress Index Short Form (PSI-SF) questionnaire. The core symptoms of ASD were assessed using the the Autism Diagnostic Observational Schedule (ADOS). RESULTS: During free play, infants in the HR-ASD group showed more internalizing (P < 0.001) and externalizing (P < 0.05) behaviours and less positive engagement (P < 0.01) than the TD group. In the regression analysis, we found that parenting stress had an impact on the infants' externalizing behaviours (â³R2 = 0.215). Parent negative engagement had an impact on the infants' internalizing behaviours (â³R2 = 0.451). CONCLUSIONS: The present study revealed that children at high risk for ASD exhibited more severe internalizing and externalizing behavioural problems than TD group. The parent negative engagement is associated with behavioural problems. The findings on the contribution of parents' factors to behavioural problems suggests that the parenting stress and parent-child interactions are important factors for mitigating behavioural problems.
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Trastorno del Espectro Autista , Problema de Conducta , Humanos , Lactante , Relaciones Padres-Hijo , Responsabilidad Parental , PadresRESUMEN
The centromere is an evolutionarily conserved eukaryotic protein machinery essential for precision segregation of the parental genome into two daughter cells during mitosis. Centromere protein A (CENP-A) organizes the functional centromere via a constitutive centromere-associated network composing the CENP-T complex. However, how CENP-T assembles onto the centromere remains elusive. Here we show that CENP-T binds directly to Holliday junction recognition protein (HJURP), an evolutionarily conserved chaperone involved in loading CENP-A. The binding interface of HJURP was mapped to the C terminus of CENP-T. Depletion of HJURP by CRISPR-elicited knockout minimized recruitment of CENP-T to the centromere, indicating the importance of HJURP in CEPN-T loading. Our immunofluorescence analyses indicate that HJURP recruits CENP-T to the centromere in S/G2 phase during the cell division cycle. Significantly, the HJURP binding-deficient mutant CENP-T6L failed to locate to the centromere. Importantly, CENP-T insufficiency resulted in chromosome misalignment, in particular chromosomes 15 and 18. Taken together, these data define a novel molecular mechanism underlying the assembly of CENP-T onto the centromere by a temporally regulated HJURP-CENP-T interaction.
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Proteína A Centromérica/metabolismo , Centrómero/metabolismo , Proteínas Cromosómicas no Histona/metabolismo , Proteínas de Unión al ADN/metabolismo , Fase G2/fisiología , Fase S/fisiología , Centrómero/genética , Proteína A Centromérica/genética , Proteínas Cromosómicas no Histona/genética , Proteínas de Unión al ADN/genética , Células HEK293 , Células HeLa , HumanosRESUMEN
Many non-small cell lung cancer (NSCLC) patients initially benefiting from gefitinib are confronted with acquired resistance. MiR-138 was previously stated as a growth inhibitor of several cancer cell lines including NSCLC cells and its expression level was significantly lower in gefitinib-resistant cells. The role of miR-138 in NSCLC cell lines PC9 and A549 was verified using methyl thiazolyl tetrazolium (MTT) assay and colony formation assay. Quantitative real-time PCR (RT-PCR) was employed to assess the level of miR-138 in gefitinib-sensitive PC9 cells and gefitinib-resistant PC9GR cells. Bioinformatic algorithms (TargetScan) and rVISTA 2.0 were used to predict binding sites on miR-138 and its target genes. MiR-138 inhibited cell proliferation of PC9 and A549 cells. In PC9GR cells, miR-138 expression was inhibited. Gefitinib treatment negatively regulated miR-138 in PC9 cells. Transfection of PC9GR cells with miR-138 mimics significantly reduced cell viability. MiR-138 was directly regulated by Homeobox A4 (HOXA4) via an HOXA4-binding site on the promoter region. TargetScan predicted numerous miR-138 target genes and EGFR was found to be the functional downstream effector of miR-138. We demonstrated that miR-138 is regulated by HOXA4 and exerts its functions via inhibiting EGFR expression in NSCLC cells.
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Carcinoma de Pulmón de Células no Pequeñas/genética , Resistencia a Antineoplásicos , Proteínas de Homeodominio/genética , Neoplasias Pulmonares/genética , MicroARNs/genética , Regiones no Traducidas 5' , Células A549 , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Receptores ErbB/genética , Gefitinib/farmacología , Regulación Neoplásica de la Expresión Génica , Proteínas de Homeodominio/química , Humanos , Factores de TranscripciónRESUMEN
Context: Hepatic ischemia-reperfusion injury (HIRI) is a complex process observed during liver resection and transplantation. N-acetyl-l-tryptophan (l-NAT), an antagonist of neurokinin 1 receptor, has been used for the treatment of nausea and neurodegenerative diseases. Objective: This study investigates the protective effect of l-NAT against HIRI and explores the potential underlying mechanisms. Materials and methods: Adult male Sprague-Dawley (SD) rats were randomly divided into three groups: sham, I/R and I/R + l-NAT. HIRI model was generated by clamping the hepatic artery, portal vein and common bile duct with a microvascular bulldog clamp for 45 min, and then removing the clamp and allowing reperfusion for 6 h. BRL cells were exposed to 200 µM H2O2 with or without 10 µM l-NAT for 6 h. Results: After l-NAT intervention, the structure of hepatic lobules was intact, and no swelling was noted in the cells. Furthermore, cell viability was found to be significantly enhanced when compared with the controls (p < 0.05). The mRNA and protein expression levels of serine-threonine kinase 2 (RIP2) and interleukin-1ß (IL-1ß) were significantly increased in the I/R and H2O2 groups when compared with the controls; however, these levels were significantly decreased after l-NAT intervention. Similarly, IL-1ß activity and caspase-1 activity were significantly decreased in the H2O2 group when compared with the controls, after l-NAT intervention. Conclusions: Our findings indicated that l-NAT may exert a hepatoprotective role in HIRI through inhibiting RIP2/caspase-1/IL-1ß signaling pathway, which can provide evidence for l-NAT to be a potential effective drug against HIRI during clinical practice.
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Caspasa 1/metabolismo , Interleucina-1beta/metabolismo , Hígado/irrigación sanguínea , Hígado/efectos de los fármacos , Proteína Serina-Treonina Quinasa 2 de Interacción con Receptor/metabolismo , Daño por Reperfusión/metabolismo , Daño por Reperfusión/prevención & control , Triptófano/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Peróxido de Hidrógeno/metabolismo , Hígado/metabolismo , Hígado/patología , Masculino , Estrés Oxidativo/efectos de los fármacos , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/cirugía , Transducción de Señal/efectos de los fármacos , Triptófano/farmacologíaRESUMEN
Digestion in the stomach depends on acidification of the lumen. Histamine-elicited acid secretion is triggered by activation of the PKA cascade, which ultimately results in the insertion of gastric H,K-ATPases into the apical plasma membranes of parietal cells. Our recent study revealed the functional role of PKA-MST4-ezrin signaling axis in histamine-elicited acid secretion. However, it remains uncharacterized how the PKA-MST4-ezrin signaling axis operates the insertion of H,K-ATPases into the apical plasma membranes of gastric parietal cells. Here we show that MST4 phosphorylates ACAP4, an ARF6 GTPase-activating protein, at Thr545 Histamine stimulation activates MST4 and promotes MST4 interaction with ACAP4. ACAP4 physically interacts with MST4 and is a cognate substrate of MST4 during parietal cell activation. The phosphorylation site of ACAP4 by MST4 was mapped to Thr545 by mass spectrometric analyses. Importantly, phosphorylation of Thr545 is essential for acid secretion in parietal cells because either suppression of ACAP4 or overexpression of non-phosphorylatable ACAP4 prevents the apical membrane reorganization and proton pump translocation elicited by histamine stimulation. In addition, persistent overexpression of MST4 phosphorylation-deficient ACAP4 results in inhibition of gastric acid secretion and blockage of tubulovesicle fusion to the apical membranes. Significantly, phosphorylation of Thr545 enables ACAP4 to interact with ezrin. Given the location of Thr545 between the GTPase-activating protein domain and the first ankyrin repeat, we reason that MST4 phosphorylation elicits a conformational change that enables ezrin-ACAP4 interaction. Taken together, these results define a novel molecular mechanism linking the PKA-MST4-ACAP4 signaling cascade to polarized acid secretion in gastric parietal cells.
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Proteínas del Citoesqueleto/metabolismo , Proteínas Activadoras de GTPasa/metabolismo , ATPasa Intercambiadora de Hidrógeno-Potásio/metabolismo , Modelos Biológicos , Células Parietales Gástricas/metabolismo , Procesamiento Proteico-Postraduccional , Proteínas Serina-Treonina Quinasas/metabolismo , Sustitución de Aminoácidos , Animales , Membrana Celular/enzimología , Membrana Celular/metabolismo , Membrana Celular/ultraestructura , Polaridad Celular , Células Cultivadas , Biología Computacional , Proteínas del Citoesqueleto/química , Proteínas del Citoesqueleto/genética , Bases de Datos de Proteínas , Proteínas Activadoras de GTPasa/química , Proteínas Activadoras de GTPasa/genética , Microscopía Electrónica de Transmisión , Mutación , Células Parietales Gástricas/citología , Células Parietales Gástricas/ultraestructura , Fosforilación , Conformación Proteica , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Transporte de Proteínas , Conejos , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/metabolismoRESUMEN
The function of melatonin as a protective agent against newborn hypoxic-ischemic (H-I) brain injury is not yet well studied, and the mechanisms by which melatonin causes neuroprotection in neurological diseases are still evolving. This study was designed to investigate whether expression of MT1 receptors is reduced in newborn H-I brain injury and whether the protective action of melatonin is by alterations of the MT1 receptors. We demonstrated that there was significant reduction in MT1 receptors in ischemic brain of mouse pups in vivo following H-I brain injury and that melatonin offers neuroprotection through upregulation of MT1 receptors. The role of MT1 receptors was further supported by observation of increased mortality in MT1 knockout mice following H-I brain injury and the reversal of the inhibitory role of melatonin on mitochondrial cell death pathways by the melatonin receptor antagonist, luzindole. These data demonstrate that melatonin mediates its neuroprotective effect in mouse models of newborn H-I brain injury, at least in part, by the restoration of MT1 receptors, the inhibition of mitochondrial cell death pathways and the suppression of astrocytic and microglial activation.
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Hipoxia-Isquemia Encefálica/tratamiento farmacológico , Hipoxia-Isquemia Encefálica/metabolismo , Melatonina/uso terapéutico , Receptor de Melatonina MT1/metabolismo , Animales , Astrocitos/citología , Western Blotting , Células Cultivadas , Femenino , Genotipo , Hipocampo/citología , Inmunohistoquímica , Masculino , Potenciales de la Membrana/fisiología , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Modelos Teóricos , Receptor de Melatonina MT1/genéticaRESUMEN
Cell migration is orchestrated by dynamic interactions of microtubules with the plasma membrane cortex. How these interactions facilitate these dynamic processes is still being actively investigated. TIP150 is a newly characterized microtubule plus end tracking protein essential for mitosis and entosis (Ward, T., Wang, M., Liu, X., Wang, Z., Xia, P., Chu, Y., Wang, X., Liu, L., Jiang, K., Yu, H., Yan, M., Wang, J., Hill, D. L., Huang, Y., Zhu, T., and Yao, X. (2013) Regulation of a dynamic interaction between two microtubule-binding proteins, EB1 and TIP150, by the mitotic p300/CBP-associated factor (PCAF) orchestrates kinetochore microtubule plasticity and chromosome stability during mitosis. J. Biol. Chem. 288, 15771-15785; Xia, P., Zhou, J., Song, X., Wu, B., Liu, X., Li, D., Zhang, S., Wang, Z., Yu, H., Ward, T., Zhang, J., Li, Y., Wang, X., Chen, Y., Guo, Z., and Yao, X. (2014) Aurora A orchestrates entosis by regulating a dynamic MCAK-TIP150 interaction. J. Mol. Cell Biol. 6, 240-254). Here we show that TIP150 links dynamic microtubules to steer cell migration by interacting with cortactin. Mechanistically, TIP150 binds to cortactin via its C-terminal tail. Interestingly, the C-terminal TIP150 proline-rich region (CT150) binds to the Src homology 3 domain of cortactin specifically, and such an interaction is negatively regulated by EGF-elicited tyrosine phosphorylation of cortactin. Importantly, suppression of TIP150 or overexpression of phospho-mimicking cortactin inhibits polarized cell migration. In addition, CT150 disrupts the biochemical interaction between TIP150 and cortactin in vitro, and perturbation of the TIP150-cortactin interaction in vivo using a membrane-permeable TAT-CT150 peptide results in an inhibition of directional cell migration. We reason that a dynamic TIP150-cortactin interaction orchestrates directional cell migration via coupling dynamic microtubule plus ends to the cortical cytoskeleton.
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Movimiento Celular/fisiología , Cortactina/metabolismo , Proteínas Asociadas a Microtúbulos/metabolismo , Microtúbulos/metabolismo , Cortactina/genética , Células HEK293 , Humanos , Proteínas Asociadas a Microtúbulos/genética , Microtúbulos/genética , Unión Proteica , Dominios Homologos srcRESUMEN
The digestive function of the stomach depends on acidification of the gastric lumen. Acid secretion into the lumen is triggered by activation of the PKA cascade, which ultimately results in the insertion of gastric H,K-ATPases into the apical plasma membranes of parietal cells. A coupling protein is ezrin, whose phosphorylation at Ser-66 by PKA is required for parietal cell activation. However, little is known regarding the molecular mechanism(s) by which this signaling pathway operates in gastric acid secretion. Here we show that PKA cooperates with MST4 to orchestrate histamine-elicited acid secretion by phosphorylating ezrin at Ser-66 and Thr-567. Histamine stimulation activates PKA, which phosphorylates MST4 at Thr-178 and then promotes MST4 kinase activity. Interestingly, activated MST4 then phosphorylates ezrin prephosphorylated by PKA. Importantly, MST4 is important for acid secretion in parietal cells because either suppression of MST4 or overexpression of non-phosphorylatable MST4 prevents the apical membrane reorganization and proton pump translocation elicited by histamine stimulation. In addition, overexpressing MST4 phosphorylation-deficient ezrin results in an inhibition of gastric acid secretion. Taken together, these results define a novel molecular mechanism linking the PKA-MST4-ezrin signaling cascade to polarized epithelial secretion in gastric parietal cells.
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Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Ácido Gástrico/metabolismo , Histamina/farmacología , Células Parietales Gástricas/efectos de los fármacos , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Proteínas del Citoesqueleto/metabolismo , Células Parietales Gástricas/metabolismo , Fosforilación , Unión Proteica , Conejos , Transducción de SeñalRESUMEN
N-acetylserotonin (NAS) is an immediate precursor of melatonin, which we have reported is neuroprotective against ischemic injury. Here we test whether NAS is a potential neuroprotective agent in experimental models of ischemic injury. We demonstrate that NAS inhibits cell death induced by oxygen-glucose deprivation or H2O2 in primary cerebrocortical neurons and primary hippocampal neurons in vitro, and organotypic hippocampal slice cultures ex vivo and reduces hypoxia/ischemia injury in the middle cerebral artery occlusion mouse model of cerebral ischemia in vivo. We find that NAS is neuroprotective by inhibiting the mitochondrial cell death pathway and the autophagic cell death pathway. The neuroprotective effects of NAS may result from the influence of mitochondrial permeability transition pore opening, mitochondrial fragmentation, and inhibition of the subsequent release of apoptogenic factors cytochrome c, Smac, and apoptosis-inducing factor from mitochondria to cytoplasm, and activation of caspase-3, -9, as well as the suppression of the activation of autophagy under stress conditions by increasing LC3-II and Beclin-1 levels and decreasing p62 level. However, NAS, unlike melatonin, does not provide neuroprotection through the activation of melatonin receptor 1A. We demonstrate that NAS reaches the brain subsequent to intraperitoneal injection using liquid chromatography/mass spectrometry analysis. Given that it occurs naturally and has low toxicity, NAS, like melatonin, has potential as a novel therapy for ischemic injury.
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Autofagia/efectos de los fármacos , Isquemia Encefálica/patología , Muerte Celular/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Fármacos Neuroprotectores , Serotonina/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Proteínas Reguladoras de la Apoptosis/genética , Proteínas Reguladoras de la Apoptosis/fisiología , Células Cultivadas , Corteza Cerebral/citología , Corteza Cerebral/patología , Hipocampo/citología , Hipocampo/patología , Peróxido de Hidrógeno/toxicidad , Inmunohistoquímica , Infarto de la Arteria Cerebral Media/patología , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Ratones , Ratones Endogámicos C57BL , Permeabilidad , Serotonina/metabolismo , Serotonina/farmacología , Transducción de Señal/efectos de los fármacos , Fracciones Subcelulares/efectos de los fármacosRESUMEN
Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease characterized by progressive motor neuron loss. Evidence suggests that mitochondrial dysfunction, apoptosis, oxidative stress, inflammation, glutamate excitotoxicity, and proteasomal dysfunction are all responsible for ALS pathogenesis. N-acetyl-tryptophan has been identified as an inhibitor of mitochondrial cytochrome c release and therefore is a potential neuroprotective agent. By quantifying cell death, we demonstrate that N-acetyl-l-tryptophan (L-NAT) and N-acetyl-DL-tryptophan are neuroprotective in NSC-34 motor neuron-like cells and/or primary motor neurons, while their isomer N-acetyl-d-tryptophan has no protective effect. These findings are consistent with energy minimization and molecular modeling analysis, confirming that L-NAT generates the most stable complex with the neurokinin-1 receptor (NK-1R). L-NAT inhibits the secretion of Substance P and IL-1ß (Enzyme-Linked Immunosorbent Assay and/or dot blots) and mitochondrial dysfunction by effectively inhibiting the release of cytochrome c/Smac/AIF from mitochondria into the cytoplasm and activation of apoptotic pathways, including the activation of caspase-1, -9, and -3, as well as proteasomal dysfunction through restoring chymotrypsin-like, trypsin-like, and caspase-like proteasome activity. These data provide insight into the molecular mechanisms by which L-NAT offers neuroprotection in models of ALS and suggest its potential as a novel therapeutic strategy for ALS. We demonstrate that L-NAT (N-acetyl-l-tryptophan), but not D-NAT, rescues NSC-34 cells and primary motor neurons from cell death. L-NAT inhibits the secretion of Substance P and IL-1ß, and caspase-1 activation, the release of cytochrome c/Smac/AIF, and the activation of caspase -9, and -3, as well as proteasomal dysfunction. The data suggest the potential of L-NAT as a novel therapeutic strategy for amyotrophic lateral sclerosis (ALS). AIF, apoptosis-inducing factor.
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Esclerosis Amiotrófica Lateral/patología , Neuronas Motoras/efectos de los fármacos , Antagonistas del Receptor de Neuroquinina-1/farmacología , Fármacos Neuroprotectores/farmacología , Triptófano/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Caspasas/metabolismo , Línea Celular , Citocromos c/metabolismo , Evaluación Preclínica de Medicamentos , Células Híbridas , Interleucina-1beta/metabolismo , Ratones , Mitocondrias/efectos de los fármacos , Neuronas Motoras/patología , Complejo de la Endopetidasa Proteasomal/metabolismo , Receptores de Neuroquinina-1 , Estereoisomerismo , Sustancia P/metabolismo , Triptófano/farmacologíaRESUMEN
INTRODUCTION: Interleukin-22 (IL-22) has been proven to exhibit a protective role in hepatic ischemia-reperfusion injury (HIRI). This study aimed to explore the change of IL-22 and IL-22 receptor 1 (IL-22R1) axis in HIRI and its role in mitochondrial apoptosis associated with STAT3 activation. MATERIALS AND METHODS: I/R mice were examined for the expression of IL-22, IL-22R1 and IL-22BP. The roles of IL-22 in hepatic histopathology and oxidative stress injuries (ALT, MDA and SOD) were determined. Oxidative stress damages of AML-12 cells were induced by H2O2, and were indicated by apoptosis, Ca2+ concentration, and mitochondrial function. The effects of IL-22 on p-STAT3Try705 were analyzed. RESULTS: We found that the expression of IL-22, IL-22R1, and IL-22BP was elevated 24 h after I/R induction, while decreased 48 h after I/R induction. Furthermore, we also discovered that IL-22 rescued the morphological damages and dysfunction of hepatocytes induced by H2O2, which were antagonized by IL-22BP, an endogenous antagonist of IL-22. Additionally, increased levels of Ca2+ concentration, MDA, ROS, apoptosis and mitochondrial dysfunction were noticed in H2O2-treated hepatocytes. However, IL-22 ameliorated the effects of I/R or H2O2. The protective effects of IL-22 were reversed by AG490, a specific antagonist of STAT3. CONCLUSIONS: In conclusion, our results indicated that IL-22 inhibited I/R-induced oxidative stress injury, Ca2+ overload, and mitochondrial apoptosis via STAT3 activation.
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Interleucina-22 , Daño por Reperfusión , Animales , Ratones , Ratas , Apoptosis , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/metabolismo , Hígado/metabolismo , Mitocondrias/metabolismo , Estrés Oxidativo , Ratas Sprague-Dawley , Daño por Reperfusión/metabolismoRESUMEN
Caspase-mediated cell death contributes to the pathogenesis of motor neuron degeneration in the mutant SOD1(G93A) transgenic mouse model of amyotrophic lateral sclerosis (ALS), along with other factors such as inflammation and oxidative damage. By screening a drug library, we found that melatonin, a pineal hormone, inhibited cytochrome c release in purified mitochondria and prevented cell death in cultured neurons. In this study, we evaluated whether melatonin would slow disease progression in SOD1(G93A) mice. We demonstrate that melatonin significantly delayed disease onset, neurological deterioration and mortality in ALS mice. ALS-associated ventral horn atrophy and motor neuron death were also inhibited by melatonin treatment. Melatonin inhibited Rip2/caspase-1 pathway activation, blocked the release of mitochondrial cytochrome c, and reduced the overexpression and activation of caspase-3. Moreover, for the first time, we determined that disease progression was associated with the loss of both melatonin and the melatonin receptor 1A (MT1) in the spinal cord of ALS mice. These results demonstrate that melatonin is neuroprotective in transgenic ALS mice, and this protective effect is mediated through its effects on the caspase-mediated cell death pathway. Furthermore, our data suggest that melatonin and MT1 receptor loss may play a role in the pathological phenotype observed in ALS. The above observations indicate that melatonin and modulation of Rip2/caspase-1/cytochrome c or MT1 pathways may be promising therapeutic approaches for ALS.
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Esclerosis Amiotrófica Lateral/tratamiento farmacológico , Antioxidantes/uso terapéutico , Muerte Celular/efectos de los fármacos , Muerte Celular/ética , Melatonina/uso terapéutico , Transducción de Señal/efectos de los fármacos , Esclerosis Amiotrófica Lateral/genética , Análisis de Varianza , Animales , Caspasa 3/metabolismo , Citocromos c/metabolismo , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Ensayo de Inmunoadsorción Enzimática , Ratones , Ratones Transgénicos , Receptor de Melatonina MT1/metabolismo , Superóxido Dismutasa/genéticaRESUMEN
The purpose of this study was to investigate the possible protective effect of N-acetylserotonin (NAS) against acute hepatic ischemia-reperfusion (I/R) injury in mice. Adult male mice were randomly divided into three groups: sham, I/R, and I/R + NAS. The hepatic I/R injury model was generated by clamping the hepatic artery, portal vein, and common bile duct with a microvascular bulldog clamp for 30 min, and then removing the clamp and allowing reperfusion for 6 h. Morphologic changes and hepatocyte apoptosis were evaluated by hematoxylin-eosin (HE) and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, respectively. Activated caspase-3 expression was evaluated by immunohistochemistry and Western blot. The activation of aspartate aminotransferase (AST), malondialdehyde (MDA), and superoxide dismutase (SOD) was evaluated by enzyme-linked immunosorbent assay (ELISA). The data show that NAS rescued hepatocyte morphological damage and dysfunction, decreased the number of apoptotic hepatocytes, and reduced caspase-3 activation. Our work demonstrates that NAS ameliorates hepatic IR injury.
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Hígado/efectos de los fármacos , Hígado/metabolismo , Daño por Reperfusión/tratamiento farmacológico , Daño por Reperfusión/metabolismo , Serotonina/análogos & derivados , Animales , Apoptosis/efectos de los fármacos , Aspartato Aminotransferasas/sangre , Western Blotting , Caspasa 3/metabolismo , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Hígado/lesiones , Masculino , Malondialdehído/sangre , Ratones , Serotonina/uso terapéutico , Superóxido Dismutasa/sangreRESUMEN
Melatonin mediates neuroprotection in several experimental models of neurodegeneration. It is not yet known, however, whether melatonin provides neuroprotection in genetic models of Huntington's disease (HD). We report that melatonin delays disease onset and mortality in a transgenic mouse model of HD. Moreover, mutant huntingtin (htt)-mediated toxicity in cells, mice, and humans is associated with loss of the type 1 melatonin receptor (MT1). We observe high levels of MT1 receptor in mitochondria from the brains of wild-type mice but much less in brains from HD mice. Moreover, we demonstrate that melatonin inhibits mutant htt-induced caspase activation and preserves MT1 receptor expression. This observation is critical, because melatonin-mediated protection is dependent on the presence and activation of the MT1 receptor. In summary, we delineate a pathologic process whereby mutant htt-induced loss of the mitochondrial MT1 receptor enhances neuronal vulnerability and potentially accelerates the neurodegenerative process.
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Enfermedad de Huntington/metabolismo , Melatonina/farmacología , Mutación/genética , Proteínas del Tejido Nervioso/genética , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Proteínas Nucleares/genética , Receptor de Melatonina MT1/metabolismo , Análisis de Varianza , Animales , Encéfalo/citología , Encéfalo/efectos de los fármacos , Encéfalo/metabolismo , Caspasa 3/análisis , Caspasa 3/metabolismo , Caspasa 9/análisis , Caspasa 9/metabolismo , Muerte Celular/efectos de los fármacos , Muerte Celular/genética , Células Cultivadas , Modelos Animales de Enfermedad , Embrión de Mamíferos , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica/genética , Proteínas Fluorescentes Verdes/genética , Humanos , Proteína Huntingtina , Enfermedad de Huntington/tratamiento farmacológico , Enfermedad de Huntington/patología , Peróxido de Hidrógeno/toxicidad , Masculino , Melatonina/uso terapéutico , Ratones , Ratones Mutantes , Persona de Mediana Edad , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Neuronas/ultraestructura , Proteínas Nucleares/metabolismo , Cambios Post Mortem , ARN Mensajero/metabolismo , ARN Interferente Pequeño/farmacología , Ratas , Receptor de Melatonina MT1/genética , Receptor de Melatonina MT2/genética , Receptor de Melatonina MT2/metabolismo , Estadísticas no Paramétricas , Factores de Tiempo , Transfección/métodosRESUMEN
Although the limbic system is closely related to emotion and social behaviors, little is known about the integrity of limbic pathways and how genetics influence the anatomical abnormalities of limbic networks in children with autism spectrum disorder (ASD). Therefore, we used an ASD twin study design to evaluate the microstructural integrity and autism-related differences in limbic pathways of young children with ASD and to estimate the heritability of limbic tracts microstructure variance. We obtained diffusion tensor imaging scans from 33 pairs of twins with ASD aged 2-9 years and 20 age-matched typically developing children. The ACE model was used to estimate the relative effects of additive genetic factors (A), shared environmental factors (C) and specific environmental factors (E) on the variability of diffusivity measurements. We found a significant decrease in fractional anisotropy (FA) in the bilateral fornix and uncinate fasciculus (UF), as well as increased mean diffusivity (MD) and radial diffusivity (RD) in the bilateral fornix and right UF of ASD children. Correlation analysis showed that FA, MD, and lateralization indices of UF were correlated with autism diagnostic observation schedule scores. The ACE model revealed that genetic effects may drive some of the variability of microstructure in the bilateral fornix, cingulum, and left UF. In conclusion, in children with ASD, there are abnormalities in the white matter microstructure of the limbic system, which is related to the core symptoms; these abnormalities may be related to the relative contribution of genetic and environmental effects on specific tracts. LAY SUMMARY: Autism spectrum disorder (ASD) children have abnormal white matter structure in limbic system related to ASD symptoms, and genetic factors play an important role in the development of limbic tracts.
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Trastorno del Espectro Autista , Sustancia Blanca , Anisotropía , Trastorno del Espectro Autista/diagnóstico por imagen , Trastorno del Espectro Autista/genética , Niño , Preescolar , Imagen de Difusión por Resonancia Magnética , Imagen de Difusión Tensora/métodos , HumanosRESUMEN
Inflammation is one of the most crucial mechanism underlying hepatic ischemia-reperfusion injury (HIRI). Several studies have shown that Ac2-26, the active N-terminal peptide of Annexin A1, could modulate anti-inflammatory processes and protect the organs from ischemia-reperfusion injury (IRI). However the effects of Ac2-26 on an HIRI model have not been reported to date. The purpose of the present study was to determine whether Ac2-26 pretreatment could protect hepatocytes against acute HIRI by inhibiting neutrophil infiltration through regulation of the high mobility group box protein 1 (HMGB1)/Toll-like receptor 4 (TLR4)/NF-κB signaling pathway. To this end, a total of 72 adult C57BL/6 mice were randomly divided into sham operation (sham), ischemia-reperfusion (I/R), I/R + Ac2-26 and Ac2-26 groups. The HIRI model was established by occluding the branch of the hepatic pedicle to the left and median liver lobes with an atraumatic vascular clamp for 45 min, followed by reperfusion for 24 h. The expression of HMGB1, TLR4, NF-κB, IκBα and lymphocyte antigen 6 complex locus G6D (Ly6G) was detected using reverse transcription-quantitative PCR, western blotting and immunohistochemical staining; serum levels of HMGB1 were evaluated using an enzyme-linked immunosorbent assay. Flow cytometry was used to detect the proportion of neutrophil. The results indicated that Ac2-26 preconditioning rescued hepatocyte dysfunctions induced by HIRI. In addition, HIRI was associated with a significant increase in HMGB1 expression and release, accompanied by increased expression of TLR4, which was significantly inhibited by Ac2-26. Furthermore, the expression of phosphorylated (p)-NF-κB and the ratio of p-NF-κB to NF-κB were markedly increased, while the expression of IκBα was decreased in the I/R group compared with those in the sham group; however, these effects were reversed by Ac2-26 administration. Additionally, Ac2-26 administration significantly inhibited neutrophil infiltration and resulted in low levels of neutrophils and Ly6G as well as reduced myeloperoxidase activity. Taken together, these results indicated that Ac2-26 pretreatment serves a protective role against HIRI by regulating the HMGB1/TLR4/NF-κB signaling pathway and inhibiting neutrophil infiltration.
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BACKGROUND: Neuronal cell apoptosis is associated with radiation exposure. It is urgent to study the radiation protection of hippocampal neurons. OBJECTIVE: The purpose of this study was to investigate the protective effect of anthocyanins on radiation and its potential mechanism. MATERIALS AND METHODS: The irradiation was carried out at room temperature with 4-Gy dose. Anthocyanins were intraperitoneally administered to rats prior to radiation exposure. The immunohistology and survival of neurons within the hippocampi, neuroprotective effects of anthocyanin, mean ROS accumulation and SIRT3 expression by Western Blot and qRTPCR were performed. RESULTS: Anthocyanins inhibit radiation-induced apoptosis by activating SIRT3. SIRT3 mRNA increased 24 hours after anthocyanin performed, accompanied by an increase in SIRT3 protein and activity. CONCLUSION: Anthocyanin can effectively resist radiation-induced oxidation and support its role in scavenging cellular reactive oxygen species. The results showed that anthocyanin protected hippocampal neurons from apoptosis through the activity of SIRT3 after irradiation.
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Antocianinas , Hipocampo , Sirtuina 3 , Animales , Antocianinas/farmacología , Apoptosis , Hipocampo/efectos de la radiación , Neuronas , Estrés Oxidativo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Sirtuina 3/genética , Sirtuina 3/metabolismo , SirtuinasRESUMEN
Hepatic ischemia-reperfusion injury (HIRI) is one of the major sources of mortality and morbidity associated with hepatic surgery. Ac2-26, a short peptide of Annexin A1 protein, has been proved to have a protective effect against IRI. However, whether it exerts a protective effect on HIRI has not been reported. The HIRI mice model and the oxidative damage model of H2O2-induced AML12 cells were established to investigate whether Ac2-26 could alleviate HIRI by regulating the activation of IL-22/IL-22R1/STAT3 signaling. The protective effect of Ac2-26 was measured by various biochemical parameters related to liver function, apoptosis, inflammatory reaction, mitochondrial function and the expressions of IL-22, IL-22R1, p-STAT3Tyr705. We discovered that Ac2-26 reduced the Suzuki score and cell death rate, and increased the cell viability after HIRI. Moreover, we unraveled that Ac2-26 significantly decreased the number of apoptotic hepatocytes, and the expressions of cleaved-caspase-3 and Bax/Bcl-2 ratio. Furthermore, HIRI increased the contents of malondialdehyde (MDA), NADP+/NADPH ratio and reactive oxygen species (ROS), whereas Ac2-26 decreased them significantly. Additionally, Ac2-26 remarkably alleviated mitochondria dysfunction, which was represented by an increase in the adenosine triphosphate (ATP) content and mitochondrial membrane potential, a decrease in mitochondrial DNA (mtDNA) damage. Finally, we revealed that Ac2-26 pretreatment could significantly inhibit the activation of IL-22/IL22R1/STAT3 signaling. In conclusion, this work demonstrated that Ac2-26 ameliorated HIRI by reducing oxidative stress and inhibiting the mitochondrial apoptosis pathway, which might be closely related to the inhibition of the IL-22/IL22R1/STAT3 signaling pathway.