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1.
J Cell Biochem ; 2019 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-30775803

RESUMO

Postoperative cognitive dysfunction (POCD) is a common complication in elderly patients who undergo surgery involving anesthesia. Its underlying mechanisms remain unclear. Autophagy plays an important role in the damage and repair of the nervous system and is associated with the development of POCD. Using a rat model, adenosine monophosphate-activated protein kinase α1 (AMPKα1), an important autophagy regulator, was found to be significantly downregulated in rats with POCD that was induced by sevoflurane anesthesia or by appendectomy. Overexpression of AMPKα1-ameliorated POCD, as indicated by decreased escape latencies and increased target quadrant swimming times, swimming distances, and platform crossing times during Morris water maze tests. AMPKα1 overexpression activated autophagy signals by increasing the expression of light chain 3 II (LC3-II) and Beclin1 and decreasing the expression of p62 in the hippocampus of rats with POCD. Moreover, blocking autophagy by 3-methyladenine partly attenuated AMPKα1-mediated POCD improvement. Furthermore, overexpression of AMPKα1 could upregulate the expression of p-AMPK and Sirt1 in the hippocampus of rats with POCD. Intriguingly, inhibiting AMPK signals via Compound C effectively attenuated AMPKα1-mediated POCD improvement, concomitant with the downregulation of p-AMPK, Sirt1, LC3-II, and Beclin1 and the upregulation of p62. We thus concluded that overexpression of AMPKα1 can improve POCD via the AMPK-Sirt1 and autophagy signaling pathway.

2.
Mol Med Rep ; 12(2): 2175-80, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25891763

RESUMO

The aim of the present study was to investigate the ultrastructural damage and the expression of heat shock protein 70 (HSP70) in the rat adenohypophysis following pulsed electromagnetic wave (PEMW) exposure. The rats were randomly divided into four groups: Sham PEMW exposure, 1 x 10(4) pulses of PEMW exposure, 1 x 10(5) pulses of PEMW exposure and 3 x 10(5) pulses of PEMW exposure. Whole body radiation of 1 x 10(4) pulses, 1 x 10(5) pulses and 3 x 10(5) pulses of PEMW were delivered with a field strength of 100 kV/m. The rats in each group (n=6 in each) were sacrificed 12, 24, 48 and 96 h after PEMW exposure. Transmission electron microscopy was then used to detect the ultrastructural changes and immunocytochemistry was used to examine the expression of HSP70. Cellular damage, including mitochondrial vacuolation occurred as early as 12 h after PEMW exposure.More severe cellular damages, including cell degeneration and necrosis, occurred 24 and 48 h after PEMW exposure. The PEMW-induced cellular damage increased as the number of PEMW pulses increased. In addition, the expression of HSP70 significantly increased following PEMW exposure and peaked after 12 h. These findings suggested that PEMW induced ultrastructural damages in the rat adenohypophysis and that HSP70 may have contributed to the PEMW-induced adenohypophyseal damage.


Assuntos
Proteínas de Choque Térmico HSP70/análise , Adeno-Hipófise/patologia , Adeno-Hipófise/efeitos da radiação , Regulação para Cima/efeitos da radiação , Animais , Radiação Eletromagnética , Imuno-Histoquímica , Masculino , Ratos , Ratos Sprague-Dawley
3.
Zhonghua Yi Xue Za Zhi ; 90(45): 3231-4, 2010 Dec 07.
Artigo em Chinês | MEDLINE | ID: mdl-21223775

RESUMO

OBJECTIVE: To investigate the exposure effect of electromagnetic pulse (EMP) on the structure and secretion of pituitary gland in rats. METHODS: Forty-eight male SD rats were randomly divided into eight groups. Four groups were subject to the EMP exposure of 200 kV/m and the others received a sham exposure. At different time points (12, 24, 48 & 96 h) post-exposure, the pathological changes of pituitary gland were observed by light and transmission electron microscope. And the serum levels of prolactin (PRL), growth hormone (GH), adrenocorticotropic hormone (ACTH), thyroid stimulating hormone (TSH) and luteinizing hormone (LH) were measured dynamically by radioimmunoassay. RESULTS: At 12 h post-exposure, swollen mitochondria with cristae loss, dilatation of Golgi complex and diffusive lysosomes were found in endocrine cells of pituitary gland. The above changes became gradually worse. Mitochondrial vacuolization, the formation of myelin figures, distinct dilatation of endoplasmic reticulum, the occurrence of numerous secondary lysosomes and the clustering of heterochromatin under the nuclear membranes could be observed at 48 h. These lesions were alleviated to some degree at 96 h. The serum levels of PRL and ACTH both increased significantly at 12 h (P < 0.01, P < 0.05) and returned to normal at 24 h. The level of GH decreased significantly at 12 h and then returned gradually to normal at 48 h. The level of TSH decreased at 12 h and reached the lowest point at 24 h, then returned to normal at 96 h. LH increased significantly from 24 h to 96 h. CONCLUSION: The EMP exposure of 200 kV/m may induce the changes of the structure and secretion of pituitary gland in rats.


Assuntos
Campos Eletromagnéticos , Hipófise/metabolismo , Hipófise/ultraestrutura , Animais , Masculino , Hipófise/efeitos da radiação , Ratos , Ratos Sprague-Dawley
4.
Int J Radiat Biol ; 83(6): 421-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17487681

RESUMO

PURPOSE: To investigate the effects of exposure to electromagnetic pulses (EMP) on functional indices of the cardiovascular system in male Sprague-Dawley rats. MATERIALS AND METHODS: A tapered parallel plate Gigahertz Transverse Electromagnetic cell (GTEM cell) with a flared rectangular coaxial transmission line was used to expose the rats to EMP (0.5 pps, total 200 pulses and whole-body averaged specific absorption rate 50 mW/kg at 200 kV/m or 75 mW/kg at 400 kV/m). Concurrent sham-exposed animals were used as controls. Cardiovascular functions, namely, heart rate, and systolic, mean and diastolic blood pressures were measured immediately and up to 4 weeks post-exposure using a non-invasive tail-cuff photoelectric sensor sphygmomanometer. RESULTS: The heart rates in sham- and EMP-exposed rats were not significantly changed. In the exposed rats, increased systolic blood pressure (SBP) occurred at 0 h and decreased SBP occurred at 1 day and 3 days after exposure. Significantly higher diastolic blood pressure (DBP) was found at 0 h and significantly lower DBP was found at 12 h, 1 day, and 1 month after exposure. Significantly higher mean arterial pressure (MAP) was noted at 0 h and significantly lower MAP was noted at 1 day. CONCLUSIONS: Significant alterations in arterial blood pressure were observed in rats exposed to EMP exposure while heart rate was not altered.


Assuntos
Velocidade do Fluxo Sanguíneo/efeitos da radiação , Pressão Sanguínea/efeitos da radiação , Campos Eletromagnéticos , Frequência Cardíaca/efeitos da radiação , Fluxo Pulsátil/efeitos da radiação , Irradiação Corporal Total/métodos , Animais , Velocidade do Fluxo Sanguíneo/fisiologia , Pressão Sanguínea/fisiologia , Relação Dose-Resposta à Radiação , Frequência Cardíaca/fisiologia , Masculino , Fluxo Pulsátil/fisiologia , Doses de Radiação , Ratos , Ratos Sprague-Dawley
5.
World J Gastroenterol ; 6(5): 709-717, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11819679

RESUMO

AIM:To clone expressed genes associated with repair of irradiation-damaged mice intestinal gland cells treated by small intestinal RNA, and to explore the molecular mechanism of exogenous nucleic acids improving repair of intestinal crypt.METHODS:The animal mode of test group and control group was established, forty-five mice being irradiated by gamma ray were treated with small intestinal RNA as test group, forty mice being irradiated by gamma ray were treated with physiological saline as control group,five mice without irradiation were used as normal control, their jejunal specimens were collected respectively at 6h, 12h,24h, 4d and 8d after irradiation. Then by using LD-PCR based on subtractive hybridization, these gene fragments differentially expressed between test group and control group were obtained, and then were cloned into T vectors as well as being sequenced. Obtained sequences were screened against. GeneBank, if being new sequences, they were submitted to GeneBank.RESULTS:Ninety clones were associated with repair of irradiation-damaged intestinal gland cells treated by intestinal RNA. These clones from test group of 6h, 12h, 24h, 4d and 8d were respectively 18, 22, 25, 13, 12. By screening against GeneBank, 18 of which were new sequences, the others were dramatically similar to the known sequences, mainly similar to hsp, Nmi,Dutt1, alkaline phosphatase, homeobox, anti-CEA ScFv antibody, arginine/serine kinase and BMP-4,repA. Eighteen gene fragments were new sequences,their accept numbers in GeneBank were respectively AF240164-AF240181.CONCLUSION:Ninety clones were obtained to be associated with repair of irradiation damaged mice intestinal gland cells treated by small intestinal RNA, which may be related to abnormal expression of genes and matched proteins of hsp, Nmi, Dutt1, Na, K-ATPase,alkalineph-osphatase, glkA, single stranded replicative centromeric gene as well as 18 new sequences.

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