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1.
Biomed Res Int ; 2021: 2237370, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34527734

RESUMO

Currently, the impact of electromagnetic field (EMF) exposure on the nervous system is an increasingly arousing public concern. The present study was designed to explore the effects of continuous long-term exposure to L-band high-power microwave (L-HPM) on brain function and related mechanisms. Forty-eight male Institute of Cancer Research (ICR) mice were exposed to L-HPM at various power densities (0.5, 1.0, and 1.5 W/m2) and the brain function was examined at different time periods after exposure. The morphology of the brain was examined by hematoxylin-eosin (HE) and deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) staining. Furthermore, cholinergic markers, oxidative stress markers, and the expression of c-fos were evaluated to identify a "potential" mechanism. The results showed that exposure to L-HPM at 1.5 W/m2 can cause generalized injuries in the hippocampus (CA1 and CA3) and cerebral cortex (the first somatosensory cortex) of mice, including cell apoptosis, cholinergic dysfunction, and oxidative damage. Moreover, the deleterious effects were closely related to the power density and exposure time, indicating that long-term and high-power density exposure may be detrimental to the nervous system.


Assuntos
Encéfalo/efeitos da radiação , Cognição/efeitos da radiação , Micro-Ondas/efeitos adversos , Acetilcolinesterase , Animais , Apoptose/fisiologia , Encéfalo/metabolismo , Córtex Cerebral/metabolismo , Córtex Cerebral/efeitos da radiação , China , Colina O-Acetiltransferase , Campos Eletromagnéticos/efeitos adversos , Hipocampo/metabolismo , Hipocampo/efeitos da radiação , Masculino , Camundongos , Camundongos Endogâmicos ICR , Neurônios/metabolismo , Neurônios/efeitos da radiação , Estresse Oxidativo/fisiologia , Proteínas Proto-Oncogênicas c-fos/metabolismo , Superóxido Dismutase-1
2.
Mol Med Rep ; 22(4): 2775-2782, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32945403

RESUMO

The restrictive nature of the blood brain barrier (BBB) brings a particular challenge to the treatment of central nervous system (CNS) disorders. The effect of ultra­wide band electromagnetic pulses (UWB­EMPs) on BBB permeability was examined in the present study in order to develop a safe and effective technology that opens the BBB to improve treatment options for CNS diseases. Rats were exposed to a single UWB­EMP at various field strengths (50, 200 or 400 kV/m) and the BBB was examined using albumin immunohistochemistry and Evans blue staining at different time periods (0.5, 3, 6 and 24 h) after exposure. The expression and distribution of zonula occludens 1 (ZO­1) were evaluated using western blotting to identify a potential mechanism underlying BBB permeability. The results showed that the BBB permeability of rats exposed to UWB­EMP increased immediately following UWM­EMP treatment and peaked between 3 and 6 h after UWB­EMP exposure, returning to pre­exposure levels 24 h later. The data suggested that UWB­EMP at 200 and 400 kV/m could induce BBB opening, while 50 kV/m UWB­EMP could not. The levels of ZO­1 in the cerebral cortex were significantly decreased at 3 and 6 h after exposure; however, no change was observed in the distribution of ZO­1. The present study indicated that UWB­EMP­induced BBB opening was field strength­dependent and reversible. Decreased expression of ZO­1 may be involved in the effect of UWB­EMP on BBB permeability.


Assuntos
Barreira Hematoencefálica/metabolismo , Magnetoterapia/métodos , Proteína da Zônula de Oclusão-1/metabolismo , Animais , Transporte Biológico , Regulação para Baixo , Masculino , Permeabilidade , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
3.
J Pharm Biomed Anal ; 170: 54-62, 2019 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-30904740

RESUMO

Protandim is an over-the-counter herbal dietary supplement. The key components of Protandim, i.e., epigallocatechin-3-gallate (EGCG), silibinin (SIL), and curcumin (CUR) were simultaneously analyzed through a liquid chromatography-tandem mass spectrometric (LC-MS/MS) method in plasma and different tissues after administration of Protandim in rats. The developed and validated method was employed to assess the pharmacokinetic profiles and the accumulation of EGCG, SIL, CUR in rat plasma and tissue homogenates. The plasma and tissue homogenates were subjected to liquid-liquid extraction and separated on a Hypurity C18 column (50 × 4.6 mm) with a gradient elution of water and acetonitrile. Mass spectrometric detection was performed in the multiple reaction monitoring mode (MRM) following the transitions: m/z 457.3/169.3, m/z 481.3/125.0, m/z 367.3/149.3 and m/z 609.4 /300.2 for EGCG, SIL, CUR, and RU (rutin), respectively. The concentrations of all the analytes in the range from 2 to 1000 ng/mL showed linear relationships with respective peak areas in different matrices. For all matrices, the values of inter-day and intra-day precisions and accuracies were less than 10.3% of the nominal concentration. The matrix effect, extraction recovery, dilution integrity, and stability values were all within acceptable levels. This method was successfully applied for determining the pharmacokinetics and tissue distribution of the components in rats after the intragastrical administration of a single-dose (364.5 mg/kg) or multiple-doses (1458 mg/kg) of Protandim. The data showed that EGCG, SIL, and CUR did not accumulate in rats after multiple doses of Protandim, and the three main components were distributed mainly in the small intestine.


Assuntos
Catequina/análogos & derivados , Cromatografia Líquida/métodos , Curcumina/química , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacocinética , Plasma/química , Espectrometria de Massas em Tandem/métodos , Animais , Catequina/sangue , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Distribuição Tecidual
4.
Rejuvenation Res ; 22(3): 218-229, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30215298

RESUMO

Fibrosis is the major pathological feature of chronic kidney disease (CKD). Aloe-emodin (AE), one of the main active compounds in Rhubarb, is widely used for renal protection. However, mechanisms implied in the modulation of kidney fibrosis after AE treatment for CKD remain elusive. Here, we explored the protective effects of AE for renal fibrosis and the involved mechanisms in vivo and in vitro. The renal fibrosis mice model was established by unilateral ureteral obstruction (UUO). We found that AE administration significantly ameliorated UUO-induced impairment of kidney, evidenced by improved histopathological abnormalities, body weight, and abnormal renal function in mice model. Immunohistochemical staining showed that TGF-ß1 and Fibronectin expressions were significantly decreased in UUO mice compared with sham group. Meanwhile, we found that AE suppressed the activation of the PI3K/Akt/mTOR pathway induced by TGF-ß1 in vivo. AE improved cell survival and decreased the level of fibrosis-related proteins under TGF-ß1-induced fibrosis in HK-2 cells as well as in vitro. Furthermore, both wortmannin, an inhibitor of PI3K, and short-hairpin RNAs of PI3K knockdown abrogated TGF-ß1-induced phosphorylation of Akt and mTOR, and decreased the suppression of fibrosis. These findings indicated that AE alleviated fibrosis by inhibiting PI3K/Akt/mTOR pathway in vivo and in vitro, which may provide a potential therapeutic option for CKD.


Assuntos
Antraquinonas/farmacologia , Rim/metabolismo , Rim/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo , Animais , Fibrose , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Rim/efeitos dos fármacos , Masculino , Camundongos Endogâmicos C57BL , Substâncias Protetoras/farmacologia , Transdução de Sinais/efeitos dos fármacos , Fator de Crescimento Transformador beta1 , Obstrução Ureteral/genética , Obstrução Ureteral/patologia
5.
Environ Toxicol Pharmacol ; 54: 155-161, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28735146

RESUMO

Public concern is growing about the exposure to electromagnetic fields (EMF) and its effect on male reproductive health. Detrimental effect of EMF exposure on sex hormones, reproductive performance and sex-ratio was reported. The present study was designed to clarify whether paternal exposure to electromagnetic pulse (EMP) affects offspring sex ratio in mice. 50 male BALB/c mice aged 5-6 weeks were exposed to EMP daily for 2 weeks before mated with non-exposed females at 0d, 7d, 14d, 21d and 28d after exposure. Sex hormones including total testosterone, LH, FSH, and GnRH were detected using radioimmunoassay. The sex ratio was examined by PCR and agarose gel electrophoresis. The results of D0, D21 and D28 showed significant increases compared with sham-exposed groups. The serum testosterone increased significantly in D0, D14, D21, and D28 compared with sham-exposed groups (p<0.05). Overall, this study suggested that EMP exposure may lead to the disturbance of reproductive hormone levels and affect the offspring sex ratio.


Assuntos
Campos Eletromagnéticos , Razão de Masculinidade , Testosterona/sangue , Animais , Feminino , Hormônio Liberador de Gonadotropina/sangue , Hormônio Luteinizante/sangue , Masculino , Camundongos Endogâmicos BALB C , Reprodução
6.
OMICS ; 21(2): 81-89, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28186865

RESUMO

Networked 21st century society, globalization, and communications technologies are paralleled by the rise of electromagnetic energy intensity in our environments and the growing pressure of the environtome on human biology and health. The latter is the entire complement of environmental factors, including the electromagnetic energy and the technologies that generate them, enacting on the digital citizen in the new century. Electromagnetic pulse (EMP) irradiation might have serious damaging effects not only on electronic equipment but also in the whole organism and reproductive health, through nonthermal effects and oxidative stress. We sought to determine whether EMP exposure (1) induces biological damage on reproductive health and (2) the extent to which selenium-rich Cordyceps fungi (daily coadministration) offer protection on the testicles and spermatozoa. In a preclinical randomized study, 3-week-old male BALB/c mice were repeatedly exposed to EMP (peak intensity 200 kV/m, pulse edge 3.5 ns, pulse width 15 ns, 0.1 Hz, and 400 pulses/day) 5 days per week for four consecutive weeks, with or without coadministration of daily selenium-rich Cordyceps fungi (100 mg/kg). Testicular index and spermatozoa formation were measured at baseline and 1, 7, 14, 28, and 60 day time points after EMP exposure. The group without Cordyceps cotreatment displayed decreased spermatozoa formation, shrunk seminiferous tubule diameters, and diminished antioxidative capacity at 28 and 60 days after exposure (p < 0.05). The Cordyceps daily cotreatment alleviated the testicular damage by EMP exposure, increased spermatozoa formation, and reduced apoptotic spermatogenic cells. These observations warrant further preclinical and clinical studies as an innovative approach for potential protection against electromagnetic radiation in the current age of networked society and digital citizenship.


Assuntos
Cordyceps/metabolismo , Selênio/metabolismo , Testículo/efeitos da radiação , Animais , Biomarcadores , Fenômenos Eletromagnéticos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Estresse Oxidativo/efeitos da radiação , Espermatozoides/efeitos da radiação
7.
Artigo em Inglês | MEDLINE | ID: mdl-29295490

RESUMO

More studies that are focused on the bioeffects of radio-frequency (RF) electromagnetic radiation that is generated from the communication devices, but there were few reports with confirmed results about the bioeffects of RF radiation on reproductive cells. To explore the effects of 1950 MHz RF electromagnetic radiation (EMR) on mouse Leydig (TM3) cells. TM3 cells were irradiated or sham-irradiated continuously for 24 h by the specific absorption rate (SAR) 3 W/kg radiation. At 0, 1, 2, 3, 4, and 5 days after irradiation, cell proliferation was detected by cell counting kit-8 (CCK-8) method, cell cycle distribution, percentage of apoptosis, and cellular reactive oxygen species (ROS) were examined by flow cytometry, Testosterone level was measured using enzyme-linked immunosorbent assay (ELISA) assay, messenger ribonucleic acid (mRNA) expression level of steroidogenic acute regulatory protein (StAR) and P450scc in TM3 cells was detected by real-time polymerase chain reaction (PCR). After being irradiated for 24 h, cell proliferation obviously decreased and cell cycle distribution, secretion capacity of Testosterone, and P450scc mRNA level were reduced. While cell apoptosis, ROS, and StAR mRNA level did not change significantly. The current results indicated that 24 h of exposure at 1950 MHz 3 W/kg radiation could cause some adverse effects on TM3 cells proliferation and Testosterone secretion, further studies about the biological effects in the reproductive system that are induced by RF radiation are also needed.


Assuntos
Células Intersticiais do Testículo/efeitos da radiação , Ondas de Rádio/efeitos adversos , Testosterona/antagonistas & inibidores , Animais , Apoptose/efeitos da radiação , Ciclo Celular/efeitos da radiação , Linhagem Celular , Proliferação de Células/efeitos da radiação , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , RNA Mensageiro/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Testosterona/metabolismo
8.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 31(6): 624-7, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24437301

RESUMO

OBJECTIVE: This study aims to develop a mandibular impression technique for type four edentulous jaws. METHODS: Twenty patients with type four edentulous jaws were selected for this study. The mandibular impression for each patient was made using both a traditional impression technique and the impression technique with a tissue-stop area. After the cast was made for each impression, the temporary denture bases were constructed on each cast. When the patients wear temporary denture bases, they must appreciate the degree of comfortability provided by each denture base. Whether the soft tissues that had been pushed away was also recorded. For 10 of the randomly selected patients, a complete denture was made using the traditional impression technique; the remaining ten subjects were given complete dentures constructed by the impression technique with a tissue-stop area. The number of times a review for misfit was recorded. The tissue fitness of each denture was also recorded. RESULTS: A paired t-test showed that the soft tissues that stacked on the residual ridge were more readily pushed away by the impression technique with a tissue-stop area than by the traditional impression technique. However, for all patients, the degree of comfortability did not vary when different techniques were used. The independent t-test results indicated that the differences between the fitness of dentures constructed using different impression techniques were not significant. The number of times a review for misfit conducted by the impression technique with a tissue-stop area was considerably lower than that for patients wearing traditionally dentures. CONCLUSION: Using the impression technique with a tissue-stop area can more readily push away the soft tissues packed on the residual ridge and reduce the times of review for misfit compared with using the traditional technique. However, the degree of comfortability and fitness of denture are not improved.


Assuntos
Técnica de Moldagem Odontológica , Planejamento de Dentadura , Bases de Dentadura , Humanos , Arcada Edêntula , Mandíbula
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