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Haruhiro Muratsubaki Akiko Yamaki 《Indian journal of clinical biochemistry : IJCB》2011,26(4):416-419
The effect of acute hypoxic hypoxia on the profile of plasma amino acids in rats was studied and compared to that resulting
from acute liver injury induced by giving carbon tetrachloride. In hypoxic rats exposed to 45% air in N2 for 5 h, the concentrations of branched chain amino acids, including valine, leucine and isoleucine, and aromatic amino acids
such as phenylalanine and tyrosine were significantly increased as compared to those in normoxic rats. The ratio of branched-chain
to aromatic amino acids (Fischer’s ratio) was significantly decreased. The levels of arginine and citrulline, which are related
to the urea cycle, were also depressed. Furthermore, plasma proline level was reduced in hypoxic rats. The activities of plasma
marker enzymes for tissue damage remained unchanged during hypoxia, indicating that tissue injury was not induced by exposure
to hypoxic conditions. We suggest that the characteristic profile of plasma amino acids and the Fischer ratio are valuable
tools for understanding the pathology of acute hypoxia in the absence of systemic tissue damage. 相似文献
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目的:探讨常压低氧(13.6%氧含量)运动对大鼠心肌核转录因子NF-κB、Cyt c和自噬相关基因Beclin1的影响,为运动与低氧适应机制的研究和高原训练方案的制定提供理论依据。方法:采用酶联免疫吸附技术(ELISA)分别测大鼠心肌NF-κB、Cyt c和Beclin1的含量。结果:通过运动训练、低氧适应或者是低氧运动适应,都能使NF-κB和Beclin1不同程度升高,其中以HC和HiLo较为显著,Cyt c变化不明显,提示运动训练、低氧适应或者低氧运动适应都能诱导自噬的发生。结论:自噬相关基因Beclin1在低氧训练中产生的低氧适应机制可能是低氧刺激后细胞内产生ROS,ROS激活了NF-κB信号通路,使得Beclinl与NF-κB活性增高;通过长期的运动与低氧适应,可能ROS降低有效抑制NF-κB信号通路,使Beclinl和NF-κB产生了适应性变化,Cyt c从线粒体释放较少,提示细胞凋亡率减少,从而保护心肌细胞的作用。 相似文献
3.
Feng Gao Xin-yang Hu Xiao-jie Xie Qi-yuan Xu Ya-ping Wang Xian-bao Liu Mei-xiang Xiang Yong Sun Jian-an Wang 《Journal of Zhejiang University. Science. B》2010,11(8):608-617
Mesenchymal stem cell(MSC)transplantation has shown a therapeutic potential to repair the ischemic and infracted myocardium,but the effects are limited by the apoptosis and loss of donor cells in host cardiac microenvironment.The aim of this study is to explore the cytoprotection of heat shock protein 90(Hsp90)against hypoxia and serum deprivation-induced apoptosis and the possible mechanisms in rat MSCs.Cell viability was determined by3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT)assay.Apoptosis was assessed by Hoechst 33258nuclear staining and flow cytometric analysis with annexin V/PI staining.The gene expression of Toll-like receptor-4(TLR-4)and V-erb-b2 erythroblastic leukemia viral oncogene homolog 2(ErbB2)was detected by real-time polymerase chain reaction(PCR).The protein levels of cleaved caspase-3,Bcl-2,Bcl-xL,Bax,total-ERK,phospho-ERK,totaI-Akt,phospho-Akt,and Hsp90 were detected by Western blot.The production of nitric oxide was measured by spectrophotometric assay.Hsp90 improves MSC viability and protects MSCs against apoptosis induced by serum deprivation and hypoxia.The protective role of Hsp90 not only elevates Bcl-2/Bax and Bcl-xL/Bax expression and attenuates cleaved caspase-3 expression via down-regulating membrane TLR-4 and ErbB2 receptors and then activating their downstream PI3K/Akt and ERK1/2 pathways,but also enhances the paracrine effect of MSCs.These findings demonstrated a novel and effective treatment strategy against MSC apoptosis in cell transplantation. 相似文献
4.
Mikhail Santos Cerqueira Jose Diego Sales Do Nascimento Daniel Germano Maciel Jean Artur Mendonca Barboza Wouber Herickson De Brito Vieira 《运动与健康科学(英文)》2020,9(2):152-159
Purpose:To investigate whether blood flow restriction(BFR) without concomitant exercise mitigated strength reduction and atrophy of thigh muscles in subjects under immobilization for lower limbs.Methods:The following databases were searched:PubMed,CINAHL,PEDro,Web of Science,Central,and Scopus.Results:The search identified 3 eligible studies,and the total sample in the identified studies consisted of 38 participants.Isokinetic and isometric torque of the knee flexors and extensors was examined in 2 studies.Cross-sectional area of thigh muscles was evaluated in 1 study,and thigh girth was measured in 2 studies.The BFR protocol was 5 sets of 5 min of occlusion and 3 min of free flow,twice daily for approximately 2 weeks.As a whole,the included studies indicate that BFR without exercise is able to minimize strength reduction and muscular atrophy after immobilization.It is crucial to emphasize,however,that the included studies showed a high risk of bias,especially regarding allocation concealment,blinding of outcome assessment,intention-to-treat analyses,and group similarity at baseline.Conclusion:Although potentially useful,the high risk of bias presented by original stodies limits the indication of BFR without concomitant exercise as an effective countermeasure against strength reduction and atrophy mediated by immobilization. 相似文献
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Myungjin Jung Liye Zou Jane Jie Yu Seungho Ryu Zhaowei Kong Lin Yang Minsoo Kang Jingyuan Lin Hong Li Lee Smith Paul D. Loprinzi 《运动与健康科学(英文)》2020,9(6):562-577
ObjectiveThis study aimed to examine (1) the independent effects of hypoxia on cognitive function and (2) the effects of exercise on cognition while under hypoxia.MethodsDesign: Systematic review with meta-analysis. Data sources: PubMed, Scopus, Web of Science, PsychInfo, and SPORTDiscus were searched. Eligibility criteria for selecting studies: randomized controlled trials and nonrandomized controlled studies that investigated the effects of chronic or acute exercise on cognition under hypoxia were considered (Aim 2), as were studies investigating the effects of hypoxia on cognition (Aim 1).ResultsIn total, 18 studies met our inclusionary criteria for the systematic review, and 12 studies were meta-analyzed. Exposure to hypoxia impaired attentional ability (standardized mean difference (SMD) = –0.4), executive function (SMD = –0.18), and memory function (SMD = –0.26), but not information processing (SMD = 0.27). Aggregated results indicated that performing exercise under a hypoxia setting had a significant effect on cognitive improvement (SMD = 0.3, 95% confidence interval: 0.14 – 0.45, I2 = 54%, p < 0.001). Various characteristics (e.g., age, cognitive task type, exercise type, exercise intensity, training type, and hypoxia level) moderated the effects of hypoxia and exercise on cognitive function.ConclusionExercise during exposure to hypoxia improves cognitive function. This association appears to be moderated by individual and exercise/hypoxia-related characteristics. 相似文献
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本文以29名竞技体育学院在校健康男性大学生为研究对象,研究了120w定量负荷运动时模拟低氧环境对HRV频域指标的影响。结果显示:2500m模拟低氧环境120w定量负荷运动时,受试者的低频值(LF)较常氧环境显著性降低,高频值(HF)较常氧环境显著性降低,而LF/HF较常氧环境无显著性差异。研究结论:LF反映交感神经活动水平,模拟低氧(2500m)环境下LF比常氧下低,交感神经活动水平降低;HF反映副交感神经活动水平,模拟低氧(2500m)环境下HF比常氧下低,副交感神经活动水平降低;模拟低氧(2500m)环境下LF/HF较常氧无显著性差异,说明低氧对交感神经与副交感神经均衡性的影响结果不明显。 相似文献
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BackgroundQaidam cattle are local breeds that habitats in northwest China. It has many excellent characteristics, such as high cold and roughage tolerance, low oxygen adaptability, and tender meat quality. Copy number variation (CNV) can induce phenotypic changes in animals by a variety of effects, and thus affects the biological functions of the animals. To explore the molecular mechanism of its adaptation to extreme cold weather and muscle fat development, the CNV variations in the genome of three Qaidam cattle were detected by whole-genome sequencing, in this study.ResultsA total of 16,743 CNVs and 9498 copy number variable regions (CNVRs) were obtained after the screening, which accounts for 2.18% of the bovine genome. The CNVR length detected ranged from 0.3 KB to 10.77 KB, with a total length of 58.17 MB and an average length of 6.12 KB/ CNVR. Through functional enrichment of CNVR related genes, LDHB, and ME1 genes were screened as the key genes for Qaidam cattle to adapt to the cold and low oxygen environments, whereas KIT and FGF18 genes might be related to the coat color and growth. In the CNVR overlapped with QTLs, variation in CAPN1 and CAST genes might be closely related to the tender meat quality of Qaidam cattle.ConclusionsTherefore, this study provides new genetic insights on the environmental adaptability and important economic traits of Qaidam cattle.How to cite: Guo S, Wu X, Pei J, et al. Genome-wide CNV analysis reveals variants associated with high-altitude adaptation and meat traits in Qaidam cattle. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.07.006 相似文献
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为了讨论男子散打项目低氧环境下心率及主观体力感觉等级变化特征,以8名优秀男子散打运动员为研究对象,采用文献资料法、实验测试法、数理统计法对低氧环境下若干指标动态变化情况进行分析。本研究认为,同等负荷下模拟高度变化是引起散打运动员心率升高的主要因素,有无低氧刺激对于散打运动员心率影响较明显,主观体力感觉（RPE）变化特征与心率变化吻合程度较高。提示散打运动员低氧训练改变模拟高度时应遵循渐进性原则,加强首次接触低氧刺激时心率监控,在散打低氧训练中可以采用心率和主观体力感觉（RPE）结合使用,使负荷安排更合理并得到及时反馈。 相似文献
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低氧运动对大鼠促红细胞生成素的影响 总被引：8，自引：0，他引：8
目的:探讨低氧运动对大鼠血清促红细胞生成素(EPO)浓度及其在肾脏中EPO mRNA基因表达的影响,为高原训练方案的制定提供理论依据。方法:采用ELISA和RT-PCR技术分别测定大鼠血清EPO浓度和肾脏EPO mRNA表达水平。结果:低氧应激后,大鼠血清EPO均显著性升高(p<0.05),大鼠肾脏EPO mRNA表达虽呈上升趋势,但只有急性低氧安静组、急性低氧运动组和急性低氧训练组有显著性升高(p<0.05),而间歇低氧安静组和间歇低氧训练组变化不明显。结论:低氧应激,血清EPO和肾脏EPO mRNA表达升高是机体自我保护机制之一,低氧训练能使血清E-PO升高,可能是低氧环境和运动缺氧共同刺激的结果;而低氧训练后EPO mRNA表达水平变化不明显,可能是4000m海拔高度缺氧的刺激较强烈,对后续的表达造成反馈抑制作用的原因。 相似文献