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1.
Aesthet Surg J ; 44(7): 746-756, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38271268

RESUMO

BACKGROUND: Large and long ears are regarded as symbols of wealth and health in East Asian culture, and people with lying ears often want their ears to be more exposed and prominent. Surgeries to correct lying ears have been documented. OBJECTIVES: The aim of this study was to report the correction of lying ears and the aesthetic modification of helix and ear lobule with hyaluronic acid (HA) injections. METHODS: HA injections were performed at the auriculocephalic sulcus to increase the cranioauricular angle (CA) and correct lying ears. The injections at helix and lobule were case specific. The CA was measured and photographs were taken at baseline and at 1-, 3-, 6-, and 10-month follow-ups. Efficacy was assessed with the 5-point Global Aesthetic Improvement Scale (GAIS). Adverse events were recorded. RESULTS: Forty-six patients (92 ears) received HA injections and completed follow-ups. Instant correction outcomes were observed. Sixteen (34.8%) patients received 1 touch-up injection, the clinical efficacy of which persisted for 1 to 1.5 years. For over 90% of cases with touch-up treatment the GAIS was "very much improved" or "much improved" at all follow-ups. The GAIS for over 70% of cases without touch-up treatment was "very much improved" or "much improved" at 1-, 3-, and 6-month follow-ups. CA increased significantly compared with the baseline. Patients also reported "more V-shaped face shape" and "lifted jawline" effects. No serious adverse events occurred. CONCLUSIONS: As an alternative technique to surgeries, HA filler injections at the auriculocephalic sulcus effectively corrected lying ears. This technique produced immediate, long-lasting, and aesthetically pleasing results. The side effects and downtime were minimal.


Assuntos
Povo Asiático , Técnicas Cosméticas , Preenchedores Dérmicos , Estética , Ácido Hialurônico , Humanos , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/efeitos adversos , Feminino , Adulto , Técnicas Cosméticas/efeitos adversos , Preenchedores Dérmicos/administração & dosagem , Preenchedores Dérmicos/efeitos adversos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Adulto Jovem , China , Orelha Externa , Injeções , Satisfação do Paciente , Pavilhão Auricular/cirurgia , Seguimentos , População do Leste Asiático
2.
Artigo em Inglês | MEDLINE | ID: mdl-37170988

RESUMO

BACKGROUND: Structural maintenance of chromosome protein 4 (SMC4) is crucial for chromosome assembly and separation, but its role and mechanism in cardia adenocarcinoma (CA) are unknown. METHODS: SMC4 expression levels were initially detected by protein profiling in 20 pairs of CA tumor tissues and adjacent normal tissues. The level of SMC4 expression in CA cells was then evaluated using a western blot analysis. Cell proliferation was evaluated by CCK-8 and clone formation tests. Scratch and transwell tests were used to investigate cell migration as well as invasion, while through the flow cytometry, we examined the cell apoptosis and progression of the cell cycle. The regulatory effects of the epithelial-mesenchymal transition (EMT) and the Wnt/ß-catenin pathway were investigated using western blot. A tumorigenesis experiment was used to investigate the influence of SMC4 on tumor development in nude mice. RESULTS: This study showed overexpression of SMC4 in CA tissues and cells. Knockdown of SMC4 can significantly inhibit the proliferation, migration and invasion, stimulate cell apoptosis, induce cell cycle arrest in the G0/G1 phase of CA cells, and inhibit tumor growth in vivo. In addition, down-regulation of SMC4 resulted in decreased expression of Bcl-2, Cyclin D1, CDK4, CDK6, ß-catenin, phosphorylated GSK-3ß, N-cadherin, and Vimentin, with an increased level of proteins, i.e., Bax, cleaved-caspase3, and E-cadherin. When SMC4 was overexpressed, these effects were reversed. CONCLUSION: SMC4 can facilitate the biological progression of CA, suggesting that SMC4 could be a potential therapeutic target for the disease.

3.
Anim Nutr ; 11: 350-358, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36329682

RESUMO

The purpose of this study was to investigate the effects of dietary L-theanine supplementation on apparent nutrient digestibility, milk yield, milk composition, and blood biochemical indices of dairy cows under heat stress. Thirty Chinese Holstein cows (19.84 ± 2.42 kg milk/d, 192.36 ± 40.77 d in milk and 2 ± 0.93 parities) were divided into 3 groups of 10 animals each. The control group was fed a basal total mixed ration (TMR) diet, while treatment 1 (LTA16) and treatment 2 (LTA32) groups were fed a basal TMR diet supplemented with L-theanine at 16 and 32 g/cow per day, respectively. The results showed that feeding the dairy cows with LTA16 treatment decreased (P < 0.05) their rectal temperature, whereas feeding with LTA32 treatment decreased (P < 0.05) their rumen fluid ammonia nitrogen content. In comparison to the control group, the supplementation of L-theanine had no significant effect (P > 0.05) on the dry matter intake, nutrient digestibility, total volatile fatty acid (TVFA) concentration and molar proportion of volatile fatty acid, milk yield, milk composition, feed efficiency and antioxidant capacity of the dairy cows. The triglyceride (TG) content of the LTA32 group was significantly greater (P = 0.014) than that of the control group. With the increase in L-theanine dosage, the serum cholesterol (CHOL) content significantly increased (P = 0.013). The serum albumin (ALB; P = 0.067), low-density lipoprotein cholesterol (LDL-C; P = 0.053), and high-density lipoprotein cholesterol (HDL-C; P = 0.067) contents showed an upward trend as L-theanine dosage increased. Ultimately, the results of this study show that supplementing dairy cow diet with L-theanine could decrease dairy cow rectal temperature, affect lipid metabolism, and potentially relieve the heat stress of dairy cows to some extent.

4.
J Healthc Eng ; 2022: 8756844, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432843

RESUMO

Background: Gastric cancer (GC) is a highly prevalent tumor type. The dysregulated expression of melanoma deficiency factor 2 (AIM2) has been observed in a range of tumor types. Herein, we explore the role of AIM2 in the regulation of GC progression. Methods: Gastric cancer cells BGC-823 and MGC-803 in logarithmic growth phase were divided into blank group (control), Control group (NC) and SH-AIM2 group, respectively. Control group and SH-AIM2 group were transfected with AIM2 NC and SH-AIM2, respectively. Nude mice were divided into blank group (control) and SH-AIM2 group, and the treatment methods were the same as above. Differential AIM2 expression in GC tissues was assessed via bioinformatics analyses, after which western blotting was used for analyzing the AIM2 levels in tumor and paracancerous tissues from five stomach cancer patients. In addition, qPCR and protein imprinting were used to assess AIM2 expression levels in GC cells, and AIM2 knockdown was conducted in MGC-803 and BGC-823cells, after which colony formation and EdU incorporation assay were utilized to assess cell proliferation. The oncogenic role of AIM2 was then assessed in mice and validated through immunohistochemical analyses. Results: GC tissues and cell lines exhibited marked AIM2 overexpression. AIM2 knockdown significantly impaired GC cell proliferation and migration, as confirmed through in vitro assays. In vivo experiments showed that both the increment ability and invasion and migration ability of AIM2 knockdown group were significantly lower than that of control and NC the change of AIM2 protein level would affect the change of MAPK pathway related protein level. Conclusions: AIM2 knockdown markedly suppresses the proliferation, migration, as well as invasion of GC cells via the inhibition of MAPK signaling, thereby slowing tumor progression. Overall, these results suggest that further analyses of AIM2 may offer clinically valuable insights that can aid in the treatment of human GC.


Assuntos
Neoplasias Gástricas , Animais , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos Nus , Transdução de Sinais , Neoplasias Gástricas/metabolismo
5.
Anim Nutr ; 7(4): 1253-1257, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34786498

RESUMO

The present trial was performed to reveal the regulatory effects of L-theanine on the levels of lipopolysaccharide (LPS) endotoxin within different biofluids, as well as relevant inflammatory responses of dairy cattle under heat stress conditions. Thirty lactating Chinese Holstein dairy cattle (189 ± 47 days in milk, and 2 ± 1 parities) were allocated in a completely randomized design to each of 3 dietary treatments: the control (CON, 0 g/d per cow L-theanine), the low L-theanine dosage treatment (LL, 16 g/d per cow L-theanine), and the high L-theanine dosage treatment (HL, 32 g/d per cow L-theanine). This trial consisted of 38 d (7 d for adaption and 31 d for data and sample collection), and sample collection for rumen liquid, blood plasma or serum, and milk were conducted on the d 27 and 38, respectively. Dairy cattle were constantly exposed to environmental heat stress during this experiment according to the recorded temperature-humidity index (THI). In the LL treatment, LPS concentration in rumen liquid was higher (P < 0.05), whilst LPS densities in plasma and milk were lower (P < 0.05) than those of the CON. Supplementing L-theanine at 2 dosages both significantly lowered (P < 0.05) the level of interleukin (IL)-1ß in the serum. Results of the present study suggested that L-theanine could be a promising additive in reducing the detrimental effects of heat stress on dairy cows, and L-theanine supplementation at 16 g/d per cow is preferred because it reduced the LPS translocation into the peripheral blood and LPS accumulation in the milk, as well as mitigated LPS-induced inflammatory reactions in dairy cows during heat stress. Further studies are necessitated to investigate the underlying mechanisms of L-theanine in LPS alteration and inflammation alleviation.

6.
Biomed Res Int ; 2020: 5159796, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32832551

RESUMO

A systemic design was carried out to investigate the optimal combination of BET, Met-Cr, CLA, and CS for improving the meat tenderness in rats. A total of 104 six-week old male Sprague-Dawley rats were randomly assigned to 13 treatments with 4 replicates of 2 rats each. The experiments lasted for 5 weeks. The results showed that inclusion of Met-Cr decreased the contents of intramuscular fat (IMF), fat among muscle cells, and lipid droplets inside muscle cells (P < 0.05), and inclusion of CLA or Met-Cr increased the contents of IMF, fat among muscle cells, and lipid droplets inside muscle cells (P < 0.05). CS increased the contents of total collagen (TC) and soluble collagen (SC), and CLA decreased the contents of TC and SC (P < 0.05). The combination of BET and CLA increased IMF and SC contents and decreased TC contents (P < 0.05). The combination of BET and CS could increase fat contents among muscle cells and decrease TC and SC contents (P < 0.05). The combination of CLA and Met-Cr decreased IMF contents (P < 0.05). The combination of CLA and CS, as well as Met-Cr and CS, decreased fat contents among muscle cells (P < 0.05). These combinations may regulate lipogenesis and decrease the deposition of fat in muscles. There existed a significant positive correlation between IMF and SC content, which might indicate that IMF content improves meat's tenderness partly by increasing SC content in muscle.


Assuntos
Betaína/farmacologia , Cisteamina/farmacologia , Suplementos Nutricionais , Ácidos Linoleicos Conjugados/farmacologia , Carne , Metionina/farmacologia , Músculo Esquelético/metabolismo , Animais , Masculino , Ratos , Ratos Sprague-Dawley
7.
Anat Rec (Hoboken) ; 291(7): 775-80, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18543291

RESUMO

To study the regional and cellular distribution of xeroderma pigmentosum group A and B (XPA and XPB) proteins, two nucleotide excision repair (NER) factors, in the mammalian brain we used immunohistochemistry and triple fluorescent immunostaining combined with confocal microscope scanning in brain slices of adult rat brain, including the cerebral cortex, striatum, substantia nigra compacta, ventral tegmental area, red nucleus, hippocampus, and cerebellum. Both XPA and XPB proteins were mainly expressed in neurons, because the XPA- or XPB-immunopositive cells were only costained with NeuN, a specific neuronal marker, but not with glial fibrillary acidic acid, a specific astrocyte marker, in the striatum. Furthermore, XPA- and XPB-positive staining were observed in the neuronal nuclei. Such subcellular distribution was consistent with the location of the NER in the cells. This study provides the first evidence that NER factors XPA and XPB exist in the nuclei of neurons in the brain, suggesting that the NER may play important roles in the process of DNA repair in adult brain neurons.


Assuntos
Encéfalo/metabolismo , DNA Helicases/metabolismo , Reparo do DNA , Proteínas de Ligação a DNA/metabolismo , Proteína de Xeroderma Pigmentoso Grupo A/metabolismo , Animais , Encéfalo/anatomia & histologia , Imuno-Histoquímica , Masculino , Neurônios/metabolismo , Ratos , Ratos Sprague-Dawley , Distribuição Tecidual
8.
Neurobiol Dis ; 24(2): 345-56, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16996745

RESUMO

To determine whether Bcl-2 could influence adult neurogenesis and prevent apoptosis of newborn neurons, we injected Bcl-2 expressing plasmid into the lateral ventricle of rat brain immediately following a 30-min occlusion of the middle cerebral artery (MCAO). We found that Bcl-2 increased neural progenitor cells (BrdU+-DCX+) in the ipsilateral striatum, newborn immature neurons (BrdU+-Tuj-1+) and newborn mature neurons (BrdU+-MAP-2+) in the ipsilateral striatum and frontal cortex at 1 to 4 weeks following MCAO. Bcl-2 overexpression promoted development of newborn neurons into GABAergic and cholinergic neurons in the ipsilateral striatum. Moreover, Bcl-2 significantly decreased the apoptosis of newborn neurons, determined by double staining of Tuj-1 and activated caspase-3 (Tuj-1+-Casp+). These results indicate that overexpression of Bcl-2 in adult rat brain enhances neurogenesis and survival of newborn neurons. Increasing neurogenesis and preventing the death of newborn neuron may be a strategy to aid in the repair of adult brain after stroke.


Assuntos
Apoptose/genética , Infarto da Artéria Cerebral Média/metabolismo , Degeneração Neural/metabolismo , Neurônios/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Células-Tronco/metabolismo , Animais , Caspase 3/metabolismo , Diferenciação Celular/genética , Proliferação de Células , Citoproteção/genética , Modelos Animais de Doenças , Proteína Duplacortina , Vetores Genéticos/genética , Infarto da Artéria Cerebral Média/fisiopatologia , Infarto da Artéria Cerebral Média/terapia , Interneurônios/citologia , Interneurônios/metabolismo , Masculino , Degeneração Neural/fisiopatologia , Degeneração Neural/prevenção & controle , Neurônios/citologia , Prosencéfalo/citologia , Prosencéfalo/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Ratos , Ratos Sprague-Dawley , Células-Tronco/citologia , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/fisiopatologia , Acidente Vascular Cerebral/terapia , Transfecção , Resultado do Tratamento , Tubulina (Proteína)/metabolismo , Regulação para Cima/genética
9.
Anat Rec A Discov Mol Cell Evol Biol ; 287(2): 1236-45, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16265626

RESUMO

Abnormal hyperphosphorylation of the cytoskeletal protein tau is a characteristic feature of neurodegeneration in Alzheimer's disease (AD) brain. Okadaic acid (OA), a protein phosphatase inhibitor, induces neuronal death and hyperphosphorylation of tau. In the present study using a model of microinjection of OA into rat frontal cortex, we aimed to investigate if OA-induced hyperphosphorylation of tau and neuronal death are related to the expression of Bcl-2, an apoptosis inhibitor, or Bax, an apoptosis inducer. Immunohistochemistry and Western blot analysis showed that OA injection dose- and time-dependently induced the expression of Bcl-2 and Bax protein in the surrounding of OA injection areas, which were similar with that of AT8 immunostaining, a marker of hyperphosphorylated tau. However, the ratios of Bcl-2 over Bax had a negative relationship to the expression of AT8. Furthermore, double fluorescent staining showed that AT8-positive neurons mainly costained with terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labeling, a marker of DNA damage, indicating that tau hyperphosphorylation may be associated with DNA damage in the neurons of rat brain. In the areas more adjacent to the OA injection site, most neurons with AT8-positive staining showed vulnerability to OA toxicity and could be triple-stained with Bcl-2 and Bax or double-stained with Bcl-2. However, in the areas further from the OA injection site, neurons with few AT8-positive staining showed resistance to OA toxicity and only stained with Bcl-2, but not Bax. The results suggest that the ratios of Bcl-2 over Bax expression may have an effect on tau hyperphosphorylation and neuronal death following OA injection.


Assuntos
Apoptose/efeitos dos fármacos , Córtex Cerebral/efeitos dos fármacos , Inibidores Enzimáticos/toxicidade , Neurônios/efeitos dos fármacos , Ácido Okadáico/toxicidade , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Proteína X Associada a bcl-2/biossíntese , Proteínas tau/metabolismo , Animais , Contagem de Células , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Técnicas Imunoenzimáticas , Marcação In Situ das Extremidades Cortadas , Masculino , Neurônios/metabolismo , Neurônios/patologia , Fosforilação , Ratos , Ratos Sprague-Dawley
10.
Acta Pharmacol Sin ; 24(12): 1205-11, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14653945

RESUMO

AIM: To study the expression of collapsing response mediated protein-4 (CRMP-4) and nestin in the ischemic adult rat brain following transient brain ischemia. METHODS: Brain ischemia was induced by transient left middle cerebral artery occlusion (MCAO) for 60 min in adult rats. The expression of CRMP-4, nestin and bromodeoxyuridine (BrdU) was analyzed by immunohistochemical method. The co-localization of CRMP-4 and nestin or BrdU was analyzed by double staining combined with confocal laser scanning microscopy. RESULTS: CRMP-4, a marker of immature neuron, could be expressed in the ipsilateral striatum and cerebral cortex at 1st and 2nd week after the ischemia-reperfusion; nestin, a marker of neural stem cell, occurred in above regions from several hours to 2 weeks. CRMP-4 costained with nestin and with BrdU incorporation. CONCLUSION: Neural stem cells may present in the striatum and cerebral cortex of adult rat and can be triggered to differentiate into newborn neuron there by ischemic brain trauma.


Assuntos
Corpo Estriado/metabolismo , Ataque Isquêmico Transitório/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Animais , Bromodesoxiuridina/metabolismo , Córtex Cerebral/metabolismo , Proteínas de Filamentos Intermediários/metabolismo , Ataque Isquêmico Transitório/complicações , Masculino , Nestina , Ratos , Ratos Sprague-Dawley
11.
Anat Rec A Discov Mol Cell Evol Biol ; 274(1): 851-6, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-12923895

RESUMO

Double-fluorescence staining was combined with confocal laser scanning microscopy to localize fetal liver kinase-1 (Flk-1) and fms-like tyrosine kinase-1 (Flt-1) in the neonatal rat brain. The results showed that Flk-1 and Flt-1 immunostaining was observed in the cells with neuron-specific enolase, a neuronal marker, and with factor VIII (F VIII), an endothelium marker, but not in cells with glial fibrillary acidic protein (GFAP), a glial marker, of brain sections from rats on postnatal day 7 (P7). This indicates that both vascular endothelial growth factor (VEGF) receptors were distributed in the neurons and the vascular endothelium. A regional analysis showed that Flt-1 was distributed most densely in the hippocampus, followed by the retrosplenial agranular cortex and the striatum, and Flk-1 was evenly distributed throughout the brain. In a comparison of the density of immunopositive staining neurons, Flt-1 was much higher than Flk-1 in most of the brain regions. A time-course analysis showed that both Flt-1 and Flk-1 were highly expressed in the cerebral vessel of rats on P1, P7, and P14, and then declined in adults, consistent with the development of angiogenesis in neonates. In the neurons, Flt-1 was highest in the cerebral cortex and hippocampus of P1-P14 rats, and then gradually decreased, whereas Flk-1 abruptly increased and reached its highest level in adults. The results suggest that Flt-1 and Flk-1 are expressed in the neurons with their individual time-dependent manners and regional distribution in the brain. However, the significance of the neuronal distribution of Flt-1 and Flk-1 remains to be determined.


Assuntos
Envelhecimento/metabolismo , Animais Recém-Nascidos/metabolismo , Encéfalo/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Ratos/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Imuno-Histoquímica/métodos , Masculino , Microscopia Confocal , Ratos Sprague-Dawley , Coloração e Rotulagem , Distribuição Tecidual , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
12.
J Neurosci Res ; 70(2): 140-9, 2002 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-12271463

RESUMO

The antisense knockdown technique and confocal laser scanning microscopic analysis were used to elucidate vascular endothelial growth factor (VEGF) induction and its effect on DNA damage and repair in rat brain following a transient middle cerebral artery occlusion. Immunohistochemical study and in situ hybridization showed that the expression of VEGF and its mRNA was enhanced in the ischemic core and penumbra of ischemic brain. Western blot analysis further illustrated that VEGF induction was time-dependently changed in these areas. Double-staining analysis indicated that VEGF-positive staining existed in the neuron, but not in the glia, and it colocalized with excision repair cross-complementing group 6 (ERCC6) mRNA, a DNA repair factor. VEGF antisense oligodeoxynucleotide infusion reduced VEGF induction and resulted in an enlargement of infarct volume of the brain caused by ischemia. Moreover, it also increased the number of DNA damaged cells and lessened the induction of ERCC6 mRNA in ischemic brains. These results suggest that the induction of endogenous VEGF in ischemic neurons plays a neuroprotective role probably associated with the expression of ERCC6 mRNA.


Assuntos
Dano ao DNA , Reparo do DNA , Fatores de Crescimento Endotelial/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Ataque Isquêmico Transitório/fisiopatologia , Linfocinas/metabolismo , Neurônios/metabolismo , Animais , Western Blotting , Encéfalo/irrigação sanguínea , Encéfalo/metabolismo , Encéfalo/patologia , DNA Helicases/genética , DNA Helicases/metabolismo , Modelos Animais de Doenças , Fatores de Crescimento Endotelial/genética , Imuno-Histoquímica , Hibridização In Situ , Marcação In Situ das Extremidades Cortadas , Peptídeos e Proteínas de Sinalização Intercelular/genética , Ataque Isquêmico Transitório/patologia , Linfocinas/genética , Masculino , Neurônios/patologia , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima , Fator A de Crescimento do Endotélio Vascular , Fatores de Crescimento do Endotélio Vascular
13.
Sheng Li Xue Bao ; 54(4): 287-93, 2002 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-12195275

RESUMO

To study the relationship between tau hyperphosphorylation and the function of glutamate transporter okadaic acid (OA), a protein phosphatase inhibitor, 20 ng in a 0.5 microl volume, was injected into the frontal cortex of rat brain and immunostaining was used to observe the phosphorylation of tau protein and the expression of excitatory amino acid transporter 1 (EAAT1) in the brain following the injection. The results showed that (1) the neurons in the center of the injection region displayed cytoplasmic shrinkage, swelling, nuclear pyknosis, and dislocation at the early stage, and necrosis appeared 3 d after the injection. However, most neurons in the peri-injected areas showed normal morphological characters with immuno positive reaction for AT8, a tau phosphorylated marker; (2) morphological analysis showed that tau hyperphosphorylation caused by OA treatment was mainly observed in the axons and dendrites of neuronal cells at 6 h in the cell body at 1 d, which brought about dystrophic neurites and neurofibrillary tangle (NFT)-like pathological changes; (3) the induction of glutamate transporter EAAT1 was observed in the involved areas corresponding to that with AT8 immunopositive staining, and the number of EAAT1-positive staining cells markedly increased at 12 h (P<0.01), peaked at 1 d (P<0.001), then decreased at 3 d following the injection. Combined with a confocal laser scanning microscopic analysis, double fluorescent immunostaining showed that EAAT1 positive staining appeared in neurons as well as astrocytes in the peri-injected areas of the frontal cortex. These results demonstrate that OA increases glutamate transporter EAAT1 expression in neurons while it induces tau hyperphosphorylation. However, the mechanism and significance of the induction of glutamate transporter EAAT1 expression remain to be further elucidated.


Assuntos
Encéfalo/citologia , Transportador 1 de Aminoácido Excitatório/metabolismo , Neurônios/efeitos dos fármacos , Ácido Okadáico/farmacologia , Animais , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Axônios/efeitos dos fármacos , Axônios/metabolismo , Dendritos/efeitos dos fármacos , Dendritos/metabolismo , Emaranhados Neurofibrilares/patologia , Neurônios/metabolismo , Fosforilação , Ratos , Proteínas tau/metabolismo
14.
J Pineal Res ; 33(1): 48-56, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12121485

RESUMO

In the present study, double fluorescence staining combined with confocal laser scanning microscopy analysis were used to examine the effects of melatonin on ischemia-induced neuronal DNA strand breaks and its possible mechanisms in a transient middle cerebral artery (MCA) occlusion model. Results showed that melatonin dose-dependently reduced infarct areas and decreased both DNA double and single strand breaks (DSB and SSB) and enhanced cell viability in the peri-ischemic brain regions. Furthermore, Bcl-2 induction in the ischemic brain was further enhanced by melatonin treatment. Double staining analysis indicated that the cells costained for Bcl-2 and TdT-mediated-deoxyuridine triphosphate (dUTP) nick-end labeling (TUNEL), a DSB marker, displayed a relative regular morphology compared with the cells only stained with TUNEL. Transient ischemia induced an expression of excision repair cross-complementing factor 6 (ERCC6) mRNA, a gene essential for the preferential repair of nuclear excision repair, in the injured neurons. Double labeling showed that ERCC6 only co-localized with proliferating cell nuclear antigen (PCNA), a member of the nuclear excision repair complex, but not with TUNEL. Melatonin further and statistical significantly up-regulated ERCC6 mRNA expression in the peri-ischemic region of rat brains. The results suggest that neuroprotection by melatonin against ischemic injury may be related to modulation of apoptosis and DNA repair capacity.


Assuntos
Isquemia Encefálica/prevenção & controle , Dano ao DNA/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Melatonina/farmacologia , Neurônios/patologia , Fármacos Neuroprotetores/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Isquemia Encefálica/patologia , Artérias Cerebrais , DNA/efeitos dos fármacos , DNA Helicases/efeitos dos fármacos , DNA Helicases/genética , DNA Helicases/metabolismo , DNA de Cadeia Simples/efeitos dos fármacos , Modelos Animais de Doenças , Marcação In Situ das Extremidades Cortadas , Masculino , Microscopia Confocal , Neurônios/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Ratos , Ratos Sprague-Dawley
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