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BACKGROUND: GPR65 (G protein-coupled receptor 65) can sense extracellular acidic environment to regulate pathophysiological processes. Pretreatment with the GPR65 agonist BTB09089 has been proven to produce neuroprotection in acute ischemic stroke. However, whether delayed BTB09089 treatment and neuronal GPR65 activation promote neurorestoration remains unknown. METHODS: Ischemic stroke was induced in wild-type (WT) or GPR65 knockout (GPR65-/-) mice by photothrombotic ischemia. Male mice were injected intraperitoneally with BTB09089 every other day at days 3, 7, or 14 poststroke. AAV-Syn-GPR65 (adenoassociated virus-synapsin-GPR65) was utilized to overexpress GPR65 in the peri-infarct cortical neurons of GPR65-/- and WT mice. Motor function was monitored by grid-walk and cylinder tests. The neurorestorative effects of BTB09089 were observed by immunohistochemistry, Golgi-Cox staining, and Western blotting. RESULTS: BTB09089 significantly promoted motor outcomes in WT but not in GPR65-/- mice, even when BTB09089 was delayed for 3 to 7 days. BTB09089 inhibited the activation of microglia and glial scar progression in WT but not in GPR65-/- mice. Meanwhile, BTB09089 reduced the decrease in neuronal density in WT mice, but this benefit was abolished in GPR65-/- mice and reemerged by overexpressing GPR65 in peri-infarct cortical neurons. Furthermore, BTB09089 increased the GAP43 (growth-associated protein-43) and synaptophysin puncta density, dendritic spine density, dendritic branch length, and dendritic complexity by overexpressing GPR65 in the peri-infarct cortical neurons of GPR65-/- mice, which was accompanied by increased levels of p-CREB (phosphorylated cAMP-responsive element-binding protein). In addition, the therapeutic window of BTB09089 was extended to day 14 by overexpressing GPR65 in the peri-infarct cortical neurons of WT mice. CONCLUSIONS: Our findings indicated that delayed BTB09089 treatment improved neurological functional recovery and brain tissue repair poststroke through activating neuronal GRP65. GPR65 overexpression may be a potential strategy to expand the therapeutic time window of GPR65 agonists for neurorehabilitation after ischemic stroke.
Assuntos
AVC Isquêmico , Camundongos Knockout , Neurônios , Receptores Acoplados a Proteínas G , Animais , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/agonistas , Camundongos , AVC Isquêmico/metabolismo , Masculino , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Reabilitação do Acidente Vascular Cerebral , Fármacos Neuroprotetores/farmacologia , Camundongos Endogâmicos C57BLRESUMO
ABSTRACT: Studies have examined the therapeutic effect of levosimendan on cardiovascular diseases such as heart failure, perioperative cardiac surgery, and septic shock, but the specific mechanism in mice remains largely unknown. This study aimed to investigate the relaxation mechanism of levosimendan in the thoracic aorta smooth muscle of mice. Levosimendan-induced relaxation of isolated thoracic aortic rings that were precontracted with norepinephrine or KCl was recorded in an endothelium-independent manner. Vasodilatation by levosimendan was not associated with the production of the endothelial relaxation factors nitric oxide and prostaglandins. The voltage-dependent K + channel (K V ) blocker (4-aminopyridine) and selective K Ca blocker (tetraethylammonium) had no effect on thoracic aortas treated with levosimendan, indicating that K V and K Ca channels may not be involved in the levosimendan-induced relaxation mechanism. Although the inwardly rectifying K + channel (K ir ) blocker (barium chloride) and the K ATP channel blocker (glibenclamide) significantly inhibited levosimendan-induced vasodilation in the isolated thoracic aorta, barium chloride had a much stronger inhibitory effect on levosimendan-induced vasodilation than glibenclamide, suggesting that levosimendan-induced vasodilation may be mediated by K ir channels. The vasodilation effect and expression of K ir 2.1 induced by levosimendan were further enhanced by the PKC inhibitor staurosporine. Extracellular calcium influx was inhibited by levosimendan without affecting intracellular Ca 2+ levels in the isolated thoracic aorta. These results suggest that K ir channels play a more important role than K ATP channels in regulating vascular tone in larger arteries and that the activity of the K ir channel is enhanced by the PKC pathway.
Assuntos
Aorta Torácica , Músculo Liso Vascular , Proteína Quinase C , Simendana , Vasodilatação , Animais , Aorta Torácica/efeitos dos fármacos , Aorta Torácica/metabolismo , Simendana/farmacologia , Masculino , Vasodilatação/efeitos dos fármacos , Proteína Quinase C/metabolismo , Proteína Quinase C/antagonistas & inibidores , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Camundongos , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/antagonistas & inibidores , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Vasodilatadores/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Bloqueadores dos Canais de Potássio/farmacologiaRESUMO
PURPOSE: This study aimed to investigate whether inhibition of glucagon-like peptide-1 (GLP-1) on pressure overload induced cardiac hypertrophy and apoptosis is related to activation of ATP sensitive potassium (KATP) channels. METHODS: Male SD rats were randomly divided into five groups: sham, control (abdominal aortic constriction), GLP-1 analog liraglutide (0.3 mg/kg/twice day), KATP channel blocker glibenclamide (5 mg/kg/day), and liraglutide plus glibenclamide. RESULTS: Relative to the control on week 16, liraglutide upregulated protein and mRNA levels of KATP channel subunits Kir6.2/SUR2 and their expression in the myocardium, vascular smooth muscle, aortic endothelium, and cardiac microvasculature. Consistent with a reduction in aortic wall thickness (61.4 ± 7.6 vs. 75.0 ± 7.6 µm, p < 0.05), liraglutide enhanced maximal aortic endothelium-dependent relaxation in response to acetylcholine (71.9 ± 8.7 vs. 38.6 ± 4.8%, p < 0.05). Along with a reduction in heart to body weight ratio (2.6 ± 0.1 vs. 3.4 ± 0.4, mg/g, p < 0.05) by liraglutide, hypertrophied cardiomyocytes (371.0 ± 34.4 vs. 933.6 ± 156.6 µm2, p < 0.05) and apoptotic cells (17.5 ± 8.2 vs. 44.7 ± 7.9%, p < 0.05) were reduced. Expression of anti-apoptotic protein BCL-2 and contents of myocardial ATP were augmented, and expression of cleaved-caspase 3 and levels of serum Tn-I/-T were reduced. Echocardiography and hemodynamic measurement showed that cardiac systolic function was enhanced as evidenced by increased ejection fraction (88.4 ± 4.8 vs. 73.8 ± 5.1%, p < 0.05) and left ventricular systolic pressure (105.2 ± 10.8 vs. 82.7 ± 7.9 mmHg, p < 0.05), and diastolic function was preserved as shown by a reduction of ventricular end-diastolic pressure (-3.1 ± 2.9 vs. 6.7 ± 2.8 mmHg, p < 0.05). Furthermore, left ventricular internal diameter at end-diastole (5.8 ± 0.5 vs. 7.7 ± 0.6 mm, p < 0.05) and left ventricular internal diameter at end-systole (3.0 ± 0.6 vs. 4.7 ± 0.4 mm, p < 0.05) were improved. Dietary administration of glibenclamide alone did not alter all the parameters measured but significantly blocked liraglutide-exerted cardioprotection. CONCLUSION: Liraglutide ameliorates cardiac hypertrophy and apoptosis, potentially via activating KATP channel-mediated signaling pathway. These data suggest that liraglutide might be considered as an adjuvant therapy to treat patients with heart failure.
Assuntos
Apoptose/efeitos dos fármacos , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Glibureto/farmacologia , Canais KATP/efeitos dos fármacos , Liraglutida/farmacologia , Animais , Cardiomegalia , Quimioterapia Combinada , Masculino , Distribuição Aleatória , Ratos , Ratos Sprague-DawleyRESUMO
BACKGROUND: Lung cancer is the most prevalent and deadliest cancer worldwide. The present study aims to determine the prognosis value of low expression long non-coding RNAs (lncRNAs) in LUAD. METHODS: RNA-seq data and clinical information were downloaded from The Cancer Genome Atlas (TCGA) data-base. Dysregulated genes between LUAD and paracancerous tissue were screened by GeneSpringGX. Prognostic lncRNAs which were low expressed in LUAD were filtrated by Ualcan, then further verified through the TCGA database. The association between clinicopathological features and the expression level of these lncRNAs was tested by chi-square test. Cox regression analysis was performed to test independent prognosis risk factors. Diagnostic efficiency was predicted by receiver operating characteristic (ROC) analysis. Gene Ontology (GO) functional and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to explore potential functions of these prognostic signatures. RESULTS: Nine prognostic lncRNAs (LINC00092, LINC00908, WWC2-AS2, RPL13AP17, CHIAP2, SFTA1P, SIGLEC17P, CYP2B7P1, CYP4Z2P) were screened out through Ualcan and further verified by TCGA. Among them, six lncRNAs (RPL13AP17, CHIAP2, SFTA1P, SIGLEC17P, CYP2B7P1, CYP4Z2P) were pseudogene transcripts. Multivariate Cox regression analysis showed that three lnRNAs (LINC00908, WWC2-AS2 CYP2B7P) were independent prognostic risk factors for OS and two lncRNAs (WWC2-AS2, SIGLEC17P) were independent prognostic risk factors for RFS in LUAD patients. Meanwhile, they showed powerful diagnostic value by ROC curve analysis. GO analysis revealed correlation genes of prognostic signatures were mainly enriched in plasma membrane, plasma membrane part, purine nucleotide binding, cytoskeleton and ribonucleotide binding and KEGG pathway analysis showed mainly enriched in cell adhesion molecules. CONCLUSIONS: The results illuminated that four lncRNAs (LINC00908, WWC2-AS2, CYP2B7P, SIGLEC17P) may be a powerful diagnostic and prognostic assessment tool for human LUAD.
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Adenocarcinoma de Pulmão , Neoplasias Pulmonares , RNA Longo não Codificante , Adenocarcinoma de Pulmão/diagnóstico , Adenocarcinoma de Pulmão/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Prognóstico , RNA Longo não Codificante/genéticaRESUMO
Earlier electroencephalographic studies have compared attractive and unattractive faces and between faces with other objects, such as flowers, without revealing if a recognition memory bias toward faces and flowers exists or whether humans exhibit enhanced specific components toward all attractive objects or only toward attractive faces. For objects with similar degrees of attractiveness, we sought to determine if the N170, P1, and N250 reflect upon the attractiveness of faces and flowers and demonstrated by comparing event-related potentials of humans' different perceptual mechanisms recognizing high attractive faces and high attractive flowers. The repeated high attractive faces tended to elicit a larger N170. Simultaneously, the P1 was preferentially associated with the repeated high attractive flowers, but both indicated that the repetitive enhancement effect only occurred on repeated attractive faces. Thus, differences existed in the perceptual mechanisms for processing repeated high attractive faces and repeated high attractive flowers. However, there was no significant difference in N250 between repeated faces and repeated flowers or between high attractive faces and high attractive flowers. Consequently, high attractive faces and high attractive flowers capture the beholder's memory bias in different processing stages. The N170 and P1 components are affected by attractiveness, thereby demonstrating the differences between human perceptual mechanisms in recognizing high attractive faces and objects.
Assuntos
Beleza , Potenciais Evocados/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Percepção Social , Adulto , Eletroencefalografia , Reconhecimento Facial/fisiologia , Feminino , Humanos , Masculino , Adulto JovemRESUMO
T-cell death-associated gene 8 (TDAG8), a G-protein-coupled receptor sensing physiological or weak acids, regulates inflammatory responses. However, its role in traumatic brain injury (TBI) remains unknown. Our recent study showed that delayed CO2 postconditioning (DCPC) has neuroreparative effects after TBI. We hypothesized that activating astrocytic TDAG8 is a key mechanism for DCPC. WT and TDAG8-/- mice received DCPC daily by transiently inhaling 10% CO2 after controlled cortical impact (CCI). HBAAV2/9-GFAP-m-TDAG8-3xflag-EGFP was used to overexpress TDAG8 in astrocytes. The beam walking test, mNSS, immunofluorescence and Golgi-Cox staining were used to evaluate motor function, glial activation and dendritic plasticity. DCPC significantly improved motor function; increased total dendritic length, neuronal complexity and spine density; inhibited overactivation of astrocytes and microglia; and promoted the expression of astrocytic brain-derived neurotrophic factor in WT but not TDAG8-/- mice. Overexpressing TDAG8 in astrocytes surrounding the lesion in TDAG8-/- mice restored the beneficial effects of DCPC. Although the effects of DCPC on Days 14-28 were much weaker than those of DCPC on Days 3-28 in WT mice, these effects were further enhanced by overexpressing astrocytic TDAG8. Astrocytic TDAG8 is a key target of DCPC for TBI rehabilitation. Its overexpression is a strategy that broadens the therapeutic window and enhances the effects of DCPC.
RESUMO
Acidic postconditioning by transient CO2 inhalation applied within minutes after reperfusion has neuroprotective effects in the acute phase of stroke. However, the effects of delayed chronic acidic postconditioning (DCAPC) initiated during the subacute phase of stroke or other acute brain injuries are unknown. Mice received daily DCAPC by inhaling 5%/10%/20% CO2 for various durations (three cycles of 10- or 20-min CO2 inhalation/10-min break) at days 3-7, 7-21, or 3-21 after photothrombotic stroke. Grid-walk, cylinder, and gait tests were used to assess motor function. DCAPC with all CO2 concentrations significantly promoted motor functional recovery, even when DCAPC was delayed for 3-7 days. DCAPC enhanced the puncta density of GAP-43 (a marker of axon growth and regeneration) and synaptophysin (a marker of synaptogenesis) and reduced the amoeboid microglia number, glial scar thickness and mRNA expression of CD16 and CD32 (markers of proinflammatory M1 microglia) compared with those of the stroke group. Cerebral blood flow (CBF) increased in response to DCAPC. Furthermore, the mRNA expression of TDAG8 (a proton-activated G-protein-coupled receptor) was increased during the subacute phase of stroke, while DCAPC effects were blocked by systemic knockout of TDAG8, except for those on CBF. DCAPC reproduced the benefits by re-expressing TDAG8 in the peri-infarct cortex of TDAG8-/- mice infected with HBAAV2/9-CMV-TDAG8-3flag-ZsGreen. Taken together, we first showed that DCAPC promoted functional recovery and brain tissue repair after stroke with a wide therapeutic time window of at least 7 days after stroke. Brain-derived TDAG8 is a direct target of DCAPC that induces neuroreparative effects.
RESUMO
AIMS: Few treatments are available in the subacute phase of traumatic brain injury (TBI) except rehabilitation training. We previously reported that transient CO2 inhalation applied within minutes after reperfusion has neuroprotective effects against cerebral ischemia/reperfusion injury. In this study, it was hypothesized that delayed CO2 postconditioning (DCPC) starting at the subacute phase may promote neurological recovery of TBI. METHODS: Using a cryogenic TBI (cTBI) model, mice received DCPC daily by inhaling 5%/10%/20% CO2 for various time-courses (one/two/three cycles of 10-min inhalation/10-min break) at Days 3-7, 3-14 or 7-18 after cTBI. Beam walking and gait tests were used to assess the effect of DCPC. Lesion size, expression of GAP-43 and synaptophysin, amoeboid microglia number and glia scar area were detected. Transcriptome and recombinant interferon regulatory factor 7 (Irf7) adeno-associated virus were applied to investigate the molecular mechanisms. RESULTS: DCPC significantly promoted recovery of motor function in a concentration and time-course dependent manner with a wide therapeutic time window of at least 7 days after cTBI. The beneficial effects of DCPC were blocked by intracerebroventricular injection of NaHCO3 . DCPC also increased puncta density of GAP-43 and synaptophysin, and reduced amoeboid microglia number and glial scar formation in the cortex surrounding the lesion. Transcriptome analysis showed many inflammation-related genes and pathways were altered by DCPC, and Irf7 was a hub gene, while overexpression of IRF7 blocked the motor function improvement of DCPC. CONCLUSIONS: We first showed that DCPC promoted functional recovery and brain tissue repair, which opens a new therapeutic time window of postconditioning for TBI. Inhibition of IRF7 is a key molecular mechanism for the beneficial effects of DCPC, and IRF7 may be a potential therapeutic target for rehabilitation after TBI.
Assuntos
Lesões Encefálicas Traumáticas , Dióxido de Carbono , Fator Regulador 7 de Interferon , Animais , Camundongos , Lesões Encefálicas Traumáticas/metabolismo , Dióxido de Carbono/metabolismo , Dióxido de Carbono/uso terapêutico , Modelos Animais de Doenças , Proteína GAP-43/metabolismo , Fator Regulador 7 de Interferon/metabolismo , Fator Regulador 7 de Interferon/uso terapêutico , Sinaptofisina/metabolismo , Sinaptofisina/uso terapêuticoRESUMO
BACKGROUND: Protective effects of ischemic preconditioning in rat small intestine have been shown to be related to the release of calcitonin gene-related peptide. AIMS: The purpose of the present study was to explore whether monophosphoryl lipid A participated in the protective process of the delayed ischemic preconditioning in the peripheral vascular bed (the anse intestinalis of rat), and whether endogenous calcitonin gene-related peptide is a mediator in this process. METHODS: Intestinal ischemia was induced by occlusion of the superior mesenteric artery for 30 min, followed by reperfusion for 60 min. The intestinal lesions were evaluated by the measurement of serum lactate dehydrogenase, myeloperoxidase levels, and small intestine tissue contents of malondialdehyde. In addition, calcitonin gene-related peptide in plasma and superior mesenteric vein effluent were also examined. RESULTS: Pretreatment with monophosphoryl lipid A (500 µg/kg. i.p.) 24 h prior to ischemia-reperfusion significantly alleviated the intestinal tissue histology lesions, decreased serum levels of lactate dehydrogenase, myeloperoxidase, and reduced tissue content of malondialdehyde. Moreover, monophosphoryl lipid A markedly increased plasma concentrations of calcitonin gene-related peptide. Pretreatment with capsaicin, which specifically depletes the neurotransmitter content of sensory nerves or calcitonin gene-related peptide-(8-37), a selective calcitonin gene-related peptide receptor antagonist, inhibited the increased calcitonin gene-related peptide release and subsequently abrogated the protection by monophosphoryl lipid A. CONCLUSIONS: In conclusion, monophosphoryl lipid A pharmacologically mimics delayed preconditioning and the protective effects are related to the stimulation of calcitonin gene-related peptide release in rat small intestine.
Assuntos
Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Intestino Delgado/efeitos dos fármacos , Lipídeo A/análogos & derivados , Traumatismo por Reperfusão/metabolismo , Animais , Peptídeo Relacionado com Gene de Calcitonina/antagonistas & inibidores , Peptídeo Relacionado com Gene de Calcitonina/genética , Capsaicina , Regulação da Expressão Gênica/fisiologia , Intestino Delgado/metabolismo , Precondicionamento Isquêmico , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Lipídeo A/farmacologia , Masculino , Malondialdeído/metabolismo , Peroxidase/genética , Peroxidase/metabolismo , Ratos , Ratos WistarRESUMO
Given that a substantial proportion of the subgroup of COVID-19 patients that face a severe disease course are younger than 60 years, it is critical to understand the disease-specific characteristics of young COVID-19 patients. Risk factors for a severe disease course for young COVID-19 patients and possible non-linear influences remain unknown. Data were analyzed from COVID-19 patients with clinical outcome in a single hospital in Wuhan, China, collected retrospectively from Jan 24th to Mar 27th. Clinical, demographic, treatment and laboratory data were collected from patients' medical records. Uni- and multivariable analysis using logistic regression and random forest, with the latter allowing the study of non-linear influences, were performed to investigate the clinical characteristics of a severe disease course. A total of 762 young patients (median age 47 years, interquartile range [IQR] 38-55, range 18-60; 55.9% female) were included, as well as 714 elderly patients as a comparison group. Among the young patients, 362 (47.5%) had a severe/critical disease course and the mean age was statistically significantly higher in the severe subgroup than in the mild subgroup (59.3 vs. 56.0, Student's t-test: p < 0.001). The uni- and multivariable analysis suggested that several covariates such as elevated levels of serum amyloid A (SAA), C-reactive protein (CRP) and lactate dehydrogenase (LDH), and decreased lymphocyte counts influence disease severity independently of age. Elevated levels of complement C3 (odds ratio [OR] 15.6, 95% CI 2.41-122.3; p = 0.039) are particularly associated with the risk of developing severe COVID-19 specifically in young patients, whereas no such influence seems to exist for elderly patients. Additional analysis suggests that the influence of complement C3 in young patients is independent of age, gender, and comorbidities. Variable importance values and partial dependence plots obtained using random forests delivered additional insights, in particular indicating non-linear influences of risk factors on disease severity. This study identified increased levels of complement C3 as a unique risk factor for adverse outcomes specific to young COVID-19 patients.
Assuntos
COVID-19/sangue , Complemento C3/análise , Adolescente , Adulto , Área Sob a Curva , COVID-19/imunologia , China/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Análise Multivariada , Dinâmica não Linear , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Adulto JovemRESUMO
OBJECTIVE: Osteosarcoma is one of the most common types of bone sarcoma with a poor prognosis. However, identifying the predictive factors that contribute to the response to neoadjuvant chemotherapy remains a significant challenge. METHODS: A public data series (GSE87437) was downloaded to identify differentially expressed genes (DEGs) and differentially expressed lncRNAs (DElncRNAs) between osteosarcoma patients that do and do not respond to preoperative chemotherapy. Subsequently, functional analysis of the transcriptome expression profile, regulatory networks of DEGs and DElncRNAs, competing endogenous RNAs (ceRNA) and protein-protein interaction networks were performed. Furthermore, the function, pathway, and survival analysis of hub genes was performed and drug and disease relationship prediction of DElncRNA was carried out. RESULTS: A total of 626 DEGs, 26 DElncRNAs, and 18 hub genes were identified. However, only one gene and two lncRNAs were found to be suitable as candidate gene and lncRNAs respectively. CONCLUSION: The DEGs, hub genes, candidate gene, and candidate lncRNAs screened out in this context were considered as potential biomarkers for the response to neoadjuvant chemotherapy of osteosarcoma.
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Neoplasias Ósseas/tratamento farmacológico , Biologia Computacional/métodos , Redes Reguladoras de Genes , Osteossarcoma/tratamento farmacológico , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/cirurgia , Bases de Dados Genéticas , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Terapia Neoadjuvante , Osteossarcoma/genética , Osteossarcoma/cirurgia , Prognóstico , Análise de SobrevidaRESUMO
Accumulating evidence suggests that chronic metformin posttreatment offers potent neuroreparative effects against acute brain injury. However, in previous studies, metformin was not initially administered beyond 24 h postinjury, and the effects of delayed metformin treatment in traumatic brain injury (TBI) and other types of acute brain injury and the related mechanisms are unclear. To test this, male C57BL/6 mice received once daily metformin treatment (20, 50 or 100 mg/kg/d, i.p.) at day 1-14, day 1-2, day 1-10, day 3-10, day 5-12 or day 5-28 after cryogenic TBI (cTBI). The results showed that 100 mg/kg/d metformin administered at day 1-14 postinjury significantly promoted motor functional recovery in the beam walking and gait tests and reduced the infarct volume. Metformin (100 mg/kg/d) administered at day 1-10 or day 3-10 but not day 1-2 or day 5-12 after cTBI significantly improved motor functional outcomes at day 7 and 14, and reduced the infarct volume at day 14. Interestingly, the therapeutic time window was further expanded when the duration of metformin treatment starting at day 5 postinjury was extended to 2 weeks. Furthermore, compared with cTBI, the administration of metformin at day 3-10 or day 5-28 after cTBI significantly elevated the expression of phosphorylated adenosine monophosphate-activated protein kinase (AMPK) and growth associated protein 43 (an axonal regeneration marker) and the number of vascular branch points and decreased the area of glial scar and the number of amoeboid microglia in the peri-infarct area at day 14 or 28 postinjury. The above beneficial effects of metformin were blocked by the intracerebroventricular injection of the AMPK inhibitor compound C (40 µg/mouse/d). Our data provide the first evidence that metformin has a wide therapeutic time window for at least 5 days after cTBI, during which it can improve functional recovery by promoting tissue repair and inhibiting glial scar formation and microglial activation in a central AMPK-dependent manner.
Assuntos
Adenilato Quinase/metabolismo , Lesões Encefálicas Traumáticas/tratamento farmacológico , Encéfalo/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Destreza Motora/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Recuperação de Função Fisiológica/efeitos dos fármacos , Animais , Encéfalo/metabolismo , Lesões Encefálicas Traumáticas/metabolismo , Modelos Animais de Doenças , Hipoglicemiantes/farmacologia , Masculino , Metformina/farmacologia , Camundongos , Fármacos Neuroprotetores/farmacologia , Fosforilação/efeitos dos fármacosRESUMO
PURPOSE: Dofetilide (DOF), a novel Class III antiarrhythmic drug, prolongs the action potential duration (APD) and shows a positive inotropic effect in guinea pig papillary muscle. The present experiments were designed to study the positive inotropic effect of DOF on rat ventricle and explore its possible mechanism(s). METHODS: Hearts from male Wistar rats (260-320 g) were divided into five groups and perfused in Langendorff mode. Ventricular myocytes were enzymatically isolated from male Wistar rats. Whole-cell voltage-clamping technique was used to test the Na(+)-Ca(2+) exchange (NCE) current (I(NCX)); Calcium transients and cell shortening provoked by field stimulation or using calcium current command waveform were observed synchronously with an ionic imaging system. RESULTS: DOF (0.03-1.0 microM) increased left ventricular function in isolated rat hearts in a concentration-dependent manner. DOF (0.03-1.0 microM) also concentration-dependently increased both inward and outward I (NCX) in isolated rat ventricular cells. The EC(50) values of DOF were 0.149 microM for the inward I(NCX) and 0.249 microM for outward I(NCX), respectively. DOF 0.2 microM significantly enhanced Ca(2+) transient and cell shortening in single rat ventricular myocytes driven by field electric stimulation. When the patch clamp system was connected to the ionic imaging system, Ca(2+) current (I(Ca)), Ca(2+) transient and cell shortening amplitude in a same cell were recorded synchronously. Application of DOF 0.2 microM had no effect on I(Ca), but significantly increased Ca(2+) transient and cell shortening. NCX inhibitor KB-R7943 0.6 microM significantly depressed the effects of DOF on Ca(2+) transient and cell shortening. CONCLUSIONS: We conclude that DOF enhanced contractility of rat ventricular myocytes. The enhancement of NCE may be involved in the positive inotropic action of DOF.
Assuntos
Antiarrítmicos/farmacologia , Contração Miocárdica/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Fenetilaminas/farmacologia , Trocador de Sódio e Cálcio/agonistas , Sulfonamidas/farmacologia , Função Ventricular Esquerda/efeitos dos fármacos , Potenciais de Ação/efeitos dos fármacos , Animais , Sinalização do Cálcio/efeitos dos fármacos , Ventrículos do Coração/citologia , Ventrículos do Coração/efeitos dos fármacos , Ventrículos do Coração/metabolismo , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/fisiologia , Técnicas de Patch-Clamp , Ratos , Ratos Wistar , Trocador de Sódio e Cálcio/antagonistas & inibidores , Tioureia/análogos & derivados , Tioureia/farmacologiaRESUMO
Glial scar impedes axon regeneration and functional recovery following traumatic brain injury (TBI). Although it has been shown that rapamycin (a specific inhibitor of mammalian target of rapamycin) can reduce astrocyte reactivation in the early stage of TBI, its effect on glial scar formation has not been characterized in TBI and other acute brain injury models. To test this, ICR mice received daily administration of rapamycin (0.5 or 1.5â¯mg/kg, i.p.) beginning at 1â¯h after cryogenic TBI (cTBI). The results showed that at 3 d post-injury, 1.5â¯mg/kg rapamycin increased cTBI-induced motor functional deficits and infarct size, and attenuated astrocyte reactivation in the ipsilateral cortex, while 0.5â¯mg/kg rapamycin did not worsen brain damage and only slightly attenuated astrocyte reactivation. Furthermore, at 7 and 14 d after cTBI, 0.5â¯mg/kg rapamycin group showed a better motor functional performance than cTBI group. At 14 d post-injury, 0.5â¯mg/kg rapamycin significantly reduced the area and thickness of glial scar and chondroitin sulfate proteoglycan expression, accompanied by decreased expression of p-S6 and enhanced expression of growth associated protein 43 (an axon regeneration marker) in the region of glial scar. Our data suggest that long-term treatment with rapamycin can inhibit glial scar formation after cTBI, which may be involved in the mechanisms of increased axon regeneration and improved neurological functional recovery, and low-dose rapamycin may be more beneficial for such a therapy.
Assuntos
Astrócitos/efeitos dos fármacos , Lesões Encefálicas Traumáticas/complicações , Encéfalo/efeitos dos fármacos , Cicatriz/metabolismo , Sirolimo/administração & dosagem , Animais , Astrócitos/metabolismo , Axônios/efeitos dos fármacos , Comportamento Animal/efeitos dos fármacos , Encéfalo/metabolismo , Proteoglicanas de Sulfatos de Condroitina/metabolismo , Cicatriz/etiologia , Temperatura Baixa , Masculino , Camundongos Endogâmicos ICR , Regeneração Nervosa/efeitos dos fármacos , Recuperação de Função Fisiológica , Teste de Desempenho do Rota-Rod , Serina-Treonina Quinases TOR/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismoRESUMO
The aberrant expression of retinoic acid receptor-α (RARα) has been reported in various types of cancer. However, its association with the prognosis and development of laryngeal squamous cell carcinoma (LSCC) has not yet been determined. Therefore, the present study aimed to examine the expression and function of RARα in patients with LSCC. The expression of RARα in LSCC tissues was investigated using immunostaining. An MTT assay and flow cytometry analysis were also performed to investigate the function of RARα in the proliferation and cell cycle of LSCC cells. The expression of RARα was significantly elevated in LSCC tissues compared with adjacent noncancerous tissues (78.1 vs. 6.3%, P<0.05). The overexpression of RARα was associated with poorly differentiated features of LSCC (P<0.05). Furthermore, the downregulation of RARα inhibited the proliferation of LSCC cells, and arrested the cell cycle at the G1 phase via upregulation of cyclin dependent kinase inhibitor 1A, which may be associated with inhibition of the protein kinase B signaling pathway. Therefore, the overexpression of RARα may contribute to the development of LSCC through the regulation of the cell cycle. The results of the present study provide evidence that RARα serves an important function in LSCC development and may be a potential therapeutic target or prognostic predictor for LSCC.
RESUMO
OBJECTIVE: To investigate a new method to construct tissue-engineering bone that will be applicable clinically. METHODS: The cultured 5th generation rabbit bone marrow stroma osteoblasts (MSO) was dissolved in 3% sodium alginate solution (the final concentration of sodium alginate in the solution being 1%, and MSO, 5x10(6)/L), and then inoculated into prepared true bone ceramic (TBC) and gelatinized the bone by dribbling with calcium gluconate. The standard bone defect models were made in 48 adult New Zealand rabbit's both radius. Among the 48 rabbits, 24 were in Groups A and B, in which the left radius was implanted with gelatinized MSO-TBC (Group A) and right radius implanted with autograft-bone (Group B); and the other 24 were in control group whose left radius was implanted with non-gelatinized MSO-TBC (Group C) and right radius implanted with gelatinized TBC (Group D). Outcomes of the implanted bones were assessed by radiology, pathological histology, osteogenetic quantitative analysis, and biomechanics at 2, 4, 8, 12 weeks postoperatively. RESULTS: In Groups A and B, a satisfactory bone reparation and bony union was noted within 12 weeks. In Groups C and D, bone reparation was not satisfied compared with Group A in terms of ostogenetic quantity and biomechanics. CONCLUSIONS: Gelatinized MSO-TBC is an ideal artificial active bone that overcomes TBC shortcomings of fragileness and smooth surface that is not eligible for seed cell's adhesion. It is promising to put into clinical use extensively.
Assuntos
Doenças Ósseas/terapia , Células da Medula Óssea/citologia , Substitutos Ósseos , Osteoblastos/citologia , Osteoblastos/transplante , Engenharia Tecidual/métodos , Animais , Biomassa , Doenças Ósseas/diagnóstico por imagem , Doenças Ósseas/patologia , Cerâmica , Modelos Animais de Doenças , Feminino , Gelatina , Masculino , Osteogênese , Coelhos , Radiografia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/lesões , Rádio (Anatomia)/patologia , Rádio (Anatomia)/cirurgia , Células Estromais/citologia , Células Estromais/transplante , Resultado do TratamentoRESUMO
OBJECTIVE: To explore the relationship between multidrug resistance (Mdr) and malignancy. To observe whether P-glycoprotein (P-gp) overexpression had the same bioactivity as osteogenic stem cell turning into more mature cell or more complex phenotype when parent cell line turned to Mdr phenotype. METHODS: Six cell sublines of Mdr phenotype with different expression degree were analyzed. Stathmin generally identified in malignancy cell and stem cell, was a microtubule associated protein and the signal of differentiation in osteogenic stem cell. RT-PCR and hybridization in situ were used to analyze the relationship between Mdr1 mRNA and expression of Stathmin mRNA and VEGF mRNA. RESULTS: Morphological and functional analysis of Mdr phenotype showed the P-gp-positive cell lines were more differentiated than the parent cells in terms of enhanced activity of cellular alkaline phosphatase. These subclones all displayed a decrease in potential malignancy such as tumor growth rate and metastatic ability. A significant negative correlation could be identified between Mdr1 mRNA and expression of VEGF and Stathmin mRNA. CONCLUSION: Expression of Mdr1/P170 indicated osteosarcoma cells differentiated towards more mature state, which will develop the new research field of Mdr and supply the new research method of the function of P- gp.
Assuntos
Diferenciação Celular , Resistência a Múltiplos Medicamentos , Resistencia a Medicamentos Antineoplásicos , Osteossarcoma/fisiopatologia , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/genética , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Expressão Gênica , Humanos , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Osteossarcoma/genética , Osteossarcoma/metabolismo , Fator A de Crescimento do Endotélio Vascular/genética , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
OBJECTIVE: To test and evaluate the olfactory function of patient after total laryngectomy, seek to a practical method to ameliorate olfactory function and rise the qualitative character of these patients. METHODS: Using the T&T olfactory examination to evaluate the olfactory function of 60 cases. Four cases olfactory mucosae were observed by electron microscope. Observing relation among the remains olfaction, the time after operation and whether or not undergone the voice reconstruction. And analyse the reasons of the above hyposomnia. Using the closing-mouth and nasal out-word airflow maneuver (CNOAM) as the intervention in the patients of tracheoesophageal fistula voice reconstruction after total laryngectomy to observe the amelioration after intervention. RESULTS: It shows various degree of hyposmia and anosmia in the cases after total laryngectomy with or without tracheoesophageal fistula voice reconstruction, with significant deference (P < 0.01) compared to the normal person respectively. There are precisely correlation among the time after operation and whether or not undergone the voice reconstruction. The longer time leads to less remaining olfaction. The patients after total laryngectomy without tracheoesophageal fistula voice reconstruction have lost their olfaction thoroughly within 5 years. But for the patients after total laryngectomy with tracheoesophageal fistula voice reconstruction, they have a middle hyposmia within 5 years, with significant deference (P < 0.01) between the patients in 5 years and after 5 years. There were significant differences (P < 0.01) between the values of patients with and without tracheoesophageal fistula voice reconstruction. The ultrastructure of 4 cases of olfactory epithelium shows the apoptosis change. After the treatment of CNOAM, the remaining olfaction of most patients were improved, with significant deference (P < 0.01) compared to those before the treatment of CNOAM. CONCLUSIONS: The proceed hypofunction of olfaction may be influenced by the reform of respiratory air, the extinction of air velocity bypass the nasal cavity and the apoptosis of epithelial cells in the patients after total laryngectomy. But if we give an early intervention study such as tracheoesophageal fistula voice reconstruction and CNOAM, the olfactory function may be maintenance. During the intervention, the ending of olfactory nerves may be get uninterrupt stimulation. This may help the patients keep a better existing quality than those fail to accept the interventions.
Assuntos
Laringectomia/efeitos adversos , Nervo Olfatório/fisiopatologia , Olfato , Adulto , Idoso , Carcinoma de Células Escamosas/fisiopatologia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Laríngeas/fisiopatologia , Masculino , Pessoa de Meia-Idade , Período Pós-OperatórioRESUMO
OBJECTIVE: To evaluate the quality of voice restored by using a tracheoesophageal slit-like fistula objectively through acoustic analysis. METHODS: Seven objective voice parameters (fundamental frequency, intensity, duration, formant F1, F2, F3 and their energy, jitter, and shimmer) of esophageal speech, Blom-Singer prosthesis voice, tracheoesophageal slit-like fistula voice, primary or modified surgical restored, and normal voice were analyzed and compared. RESULTS: T test was used for statistical analysis. The maximum phonation time of slit-like fistula voice was shorter than that of normal voice, longer than that of esophageal voice, no significant difference compared with that of Blom-Singer prosthesis voice. Its sound intensity of it was similar to that of normal voice and Blom-Singer voice, better than that of esophageal voice. Its fundamental frequency was lower than that of normal voice. Its shimmer and jitter was more than that of normal voice, less than that of esophageal voice, and similar to that of Blom-singer one. Compared with esophageal voice, all formants but F1 of it were not statistically different. No statistical difference between the 2 groups of slit-like fistula patients, i.e., the instant slit-like fistula construction after total laryngectomy and the second stage slit-like fistula construction. CONCLUSION: The voice quality of the patients with tracheoesophageal slit-like fistula is similar to that of the normal and could meet the needs of daily life.