Chinese Astronaut Research and Training Center

Chinese, China

Chinese Astronaut Research and Training Center

Chinese, China
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Shi J.,Peking University | Wang Y.,Peking University | He J.,Chinese Astronaut Research and Training Center | Li P.,Shenyang University | And 9 more authors.
FASEB Journal | Year: 2017

Exposure to microgravity leads to alterations in multiple systems, but microgravity-related changes in the gastrointestinal tract and its clinical significance have not been well studied. We used the hindlimb unloading (HU) mouse model to simulate a microgravity condition and investigated the changes in intestinal microbiota and colonic epithelial cells. Compared with ground-based controls (Ctrls), HU affected fecal microbiota composition with a profile that was characterized by the expansion of Firmicutes and decrease of Bacteroidetes. The colon epithelium of HU mice showed decreased goblet cell numbers, reduced epithelial cell turnover, and decreased expression of genes that are involved in defense and inflammatory responses. As a result, increased susceptibility to dextran sulfate sodium–induced epithelial injury was observed in HU mice. Cohousing of Ctrl mice with HU mice resulted in HU-like epithelial changes in Ctrl mice. Transplantation of feces from Ctrl to HU mice alleviated these epithelial changes in HU mice. Results indicate that HU changes intestinal microbiota, which leads to altered colonic epithelial cell homeostasis, impaired barrier function, and increased susceptibility to colitis. We further demonstrate that alteration in gastrointestinal motility may contribute to HU-associated dysbiosis. These animal results emphasize the necessity of evaluating astronauts’ intestinal homeostasis during distant space travel.—Shi, J., Wang, Y., He, J., Li, P., Jin, R., Wang, K., Xu, X., Hao, J., Zhang, Y., Liu, H., Chen, X., Wu, H., Ge, Q. Intestinal microbiota contributes to colonic epithelial changes in simulated microgravity mouse model. © FASEB.

PubMed | Chinese Astronaut Research and Training Center and Peking University
Type: Journal Article | Journal: Molecular medicine reports | Year: 2016

Rhodiolarosea (R.rosea), a type of adaptogen, has been previously reported to exhibit immunostimulating activity in rodents and in human peripheral blood mononuclear cells (PBMCs)invitro. To examine the effect of R.rosea on Tcells under simulated microgravity, spaceflight analogs of human headdown bed rest (HDBR) at 6 and murine hind limb unloading (HU) were used. A decrease in the levels of interferon (IFN) and interleukin17 (IL17) and an increase in regulatory T (Treg) cells were observed in the placebo group following HDBR. The R.rosea treated HBDR group demonstrated further decreased IFN production, however, R.rosea exhibited no effect on the ratio of circulating Tregs or Treg cell differentiation. By contrast, the treatment of R.rosea on human Tcellsinvitro did not alter IFN secretion, however, Treg differentiation was significantly reduced. An R.roseainduced upregulation of hypoxiainducible factor1 (HIF1) contributed to the suppression of Treg differentiationinvitro. Differences in the effect of R.roseainvitro andinvivo were also observed using a mouse model of microgravity. The results of the current study suggest that R.rosea has differential modulatory effects on Tcellsinvivo andinvitro and care should be taken when evaluating the effects of R.rosea on the immune system.

Lv C.,China Agricultural University | Bai Y.,China Agricultural University | Yang S.,China Agricultural University | Zhao G.,China Agricultural University | Chen B.,Chinese Astronaut Research and Training Center
Food Chemistry | Year: 2013

Plant ferritin from legume seeds co-exists with coenzyme NADH (a reduced form of nicotinamide-adenine dinucleotide) in many foodstuffs. In the present study, the interaction of NADH with apo pea seed ferritin (PSF) was investigated by fluorescence resonance energy transfer (FRET), fluorescence titration, transmission electron microscope (TEM), and isothermal titration calorimetry (ITC). We found that NADH molecules bound on the outer surface of PSF close to the 4-fold channels, which was 1.58 nm from tryptophan residue (Trp). Consequently, such binding facilitates iron release from holo PSF, which might have a negative effect on PSF as an iron supplement, while NADH was oxidised into NAD+. However, the binding of NADH to the protein does not affect the entry of toxic ferrous ions into the apo protein shell, where these ferrous ions were oxidised into less toxic ferric ions. Moreover, NADH binding markedly affects the tertiary structure around Trp residues of PSF. These findings advanced our understanding of the interactions between different naturally occurring components in a complex food system. © 2013 Elsevier Ltd.

Lu C.,China Agricultural University | Zhao G.,China Agricultural University | Zhao G.,Chinese Astronaut Research and Training Center
Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering | Year: 2015

Calcium is an essential nutrient required for critical biological functions such as nerve conduction, muscle contraction, mitosis, blood coagulation, and structural support of the skeleton. Dietary calcium intake is of general interest for human beings, particularly for infants and young children, when growth is accelerated. Milk and milk products as effective calcium supplements are generally accepted by human race with their high bioavailability. However, less consumption of milk in industrialized countries leads to inadequate calcium intake. Therefore, it is important to explore an alternate source for calcium supplement. On the other hand, dried grape seeds are likewise rich in lipids (22.07%), carbohydrates (12.51%) and proteins (11.94%) (w/w) and grape seeds as by-product during juice production can be an alternative source of protein. Meanwhile, this study demonstrates that grape seeds are rich in calcium ((5.62±0.01) g/kg for embryonic cells and (6.32± 0.01) g/kg for intact grape seeds), which was identified by ICP-AES. The calcium was mainly distributed in the stroma of the amyloplasts and around the starch granules, which was observed under TEM (Transmission Electron Microscope). Further study indicates that water-soluble protein from grape (Vitis vinifera L.) seeds (WSPG) contained two major components, one of which was 11S globulin-like protein mainly responsible for the binding of calcium in WSPG and the other was a novel protein (Protein A). The calcium contents of protein isolate from each step were identified by ICP-AES as well. When a traditional alkali extraction and acid precipitation method was used for isolation of WSPG, many binding calcium ions were lost. It is worth noting that the protein composition of grape seed protein obtained by both 30%-50% (NH4)2SO4 sediment and the alkali extraction and acid precipitation method was nearly identical, which consisted of protein A and protein B at a ratio of 2 to 3, but the content of calcium in the grape seed protein by the ammonium sulfate sediment was approximately 3-fold larger than that by the traditional method, demonstrating that the ammonium sulfate sediment was a better way to isolate mineral-containing protein as compared to the traditional method. A high yield of calcium by the ammonium sulfate sediment could be derived from its mild condition, whereas acid and alkaline used in the alkali extraction and acid precipitation possibly inhibits the binding of calcium ions with grape seed protein. The following FT-IR (Fourier transform infrared spectroscopy) study showed that the prominent band of apo grape seed protein attributed to random coils turns (1 666 cm-1) was shifted to lower wave number (1 660 cm-1) with a marked decreased in intensity upon calcium binding with the protein and indicated that the binding of calcium to the protein stabilizes the secondary structure of WGSP by changing state of C=O. Moreover, the abundant amino acid residues were found in WGSP to be glutamic and aspartic acids, which accounted for about 26.7% and 9.0% of the total amino acid, respectively, and these amino acids might be beneficial for calcium binding. This study could provide a foundation for the preparation of mineral-containing protein in food industry. This method may have a potential use in food industry for isolation of mineral-containing protein from other sources. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.

Lin M.,Xi'an University of Science and Technology | Lin M.,Xi'an Jiaotong University | Zhao Y.,Xi'an Jiaotong University | Liu M.,Xi'an Jiaotong University | And 9 more authors.
Journal of Materials Chemistry C | Year: 2014

Preparation of well-defined NaYF4 crystals with bright upconversion emission remains a major challenge. The complicated chemical reactions as well as the effect of structure, phase and morphology on the emission efficiency require fine tuning of multiple parameters during the growth of NaYF4 crystals. In this study, we successfully synthesized NaYF4:Yb3+,Er3+ microcrystals with well-controlled morphologies (e.g., sphere and tube) and enhanced luminescent intensity through tuning pH values and ion concentrations in the initial reaction solution. With increasing reaction time, the phase of NaYF 4:Yb3+,Er3+ changes from cubic to hexagonal, while the morphology follows the change from spheres to microtubes and then to microrods. Upon excitation by 980 nm infrared light, hexagonal NaYF 4:Yb3+,Er3+ microtubes show a significant enhancement in green upconversion emission, which is much stronger than that observed in particles with other morphologies. This phase and morphology dependent strong upconversion emission holds great potential for applications in photonic devices and bioanalyses. © 2014 the Partner Organisations.

Wang Y.-C.,PLA Fourth Military Medical University | Wang Y.-C.,Chinese Astronaut Research and Training Center | Yang C.-B.,PLA Fourth Military Medical University | Wu Y.-H.,PLA Fourth Military Medical University | And 6 more authors.
European Journal of Applied Physiology | Year: 2011

We have shown previously that combined short-arm centrifuge and aerobic exercise training preserved several physiologically important cardiovascular functions in humans. We hypothesized that artificial gravity (AG) and exercise is effective to prevent changes of physical problems during head-down bed rest (HDBR). To test this hypothesis, 12 healthy male subjects had undergone 4 days of 6° HDBR. Six of them were exposed to AG of an alternating 2-min intervals of +1.0 and +2.0 Gz at foot level for 30 min twice per day with ergometric exercise of 40 W as a countermeasure during bed rest (CM group), while the remaining six served as untreated controls (no-CM group). Before and after 4 days of bed rest, leg venous hemodynamics was assessed by venous occlusion plethysmography and autonomic cardiovascular control estimated by power spectral analysis of blood pressure and heart rate. Further, orthostatic tolerance was evaluated by a 75° head-up tilt test and physical working capacity was surveyed by near maximal physical working capacity test before and after bed rest. The data showed that combined centrifuge and exercise applied twice daily for a total of 60 min during 4 days of HDBR prevented (a) a decrease in working capacity, (b) autonomic dysfunction (a decrease in the activity of parasympathetic cardiac innervation) and (c) an increase in leg venous flow resistance. The combination of a 30 min alternating of +1.0 and +2.0 Gz for twice per day of AG with 40 W ergometric exercise may offer a promising countermeasure to short duration simulated microgravity. © Springer-Verlag 2011.

Shi F.,PLA Fourth Military Medical University | Wang Y.-C.,PLA Fourth Military Medical University | Zhao T.-Z.,PLA Fourth Military Medical University | Zhang S.,PLA Fourth Military Medical University | And 4 more authors.
PLoS ONE | Year: 2012

Endothelial cells are very sensitive to microgravity and the morphological and functional changes in endothelial cells are believed to be at the basis of weightlessness-induced cardiovascular deconditioning. It has been shown that the proliferation, migration, and morphological differentiation of endothelial cells play critical roles in angiogenesis. However, the influence of microgravity on the ability of endothelial cells to foster angiogenesis remains to be explored in detail. In the present study, we used a clinostat to simulate microgravity, and we observed tube formation, migration, and expression of endothelial nitric oxide synthase (eNOS) in human umbilical vein endothelial cells (HUVEC-C). Specific inhibitors of eNOS and phosphoinositide 3-kinase (PI3K) were added to the culture medium and gravity-induced changes in the pathways that mediate angiogenesis were investigated. After 24 h of exposure to simulated microgravity, HUVEC-C tube formation and migration were significantly promoted.This was reversed by co-incubation with the specific inhibitor of N-nitro-L-arginine methyl ester hydrochloride (eNOS). Immunofluorescence assay, RT-PCR, and Western blot analysis demonstrated that eNOS expression in the HUVEC-C was significantly elevated after simulated microgravity exhibition. Ultrastructure observation via transmission electron microscope showed the number of caveolae organelles in the membrane of HUVEC-C to be significantly reduced. This was correlated with enhanced eNOS activity. Western blot analysis then showed that phosphorylation of eNOS and serine/threonine kinase (Akt) were both up-regulated after exposure to simulated microgravity. However, the specific inhibitor of PI3K not only significantly downregulated the expression of phosphorylated Akt, but also downregulated the phosphorylation of eNOS. This suggested that the PI3K-Akt signal pathway might participate in modulating the activity of eNOS. In conclusion, the present study indicates that 24 h of exposure to simulated microgravity promote angiogenesis among HUVEC-C and that this process is mediated through the PI3K-Akt-eNOS signal pathway. © 2012 Shi et al.

Yang C.-B.,PLA Fourth Military Medical University | Wang Y.-C.,PLA Fourth Military Medical University | Gao Y.,PLA Fourth Military Medical University | Geng J.,PLA Fourth Military Medical University | And 5 more authors.
Cytokine | Year: 2011

Cardiovascular and musculoskeletal deconditioning occurring in long-term spaceflight requires new strategies to counteract these adverse effects. We previously reported that a short-arm centrifuge produced artificial gravity (AG), together with ergometer, has an approving effect on promoting cardiovascular function. The current study sought to investigate whether the cardiac and cerebrovascular functions were maintained and improved using a strategy of AG combined with exercise training on cardiovascular function during 4-day head-down bed rest (HDBR). Twelve healthy male subjects were assigned to a control group (CONT, n= 6) and an AG combined with ergometric exercise training group (CM, n= 6). Simultaneously, cardiac pumping and systolic functions, cerebral blood flow were measured before, during, and after HDBR. The results showed that AG combined with ergometric exercise caused an increase trend of number of tolerance, however, there was no significant difference between the two groups. After 4-day HDBR in the CONT group, heart rate increased significantly (59 ± 6 vs 66 ± 7. beats/min), while stroke volume (98 ± 12 vs 68 ± 13. mL) and cardiac output (6 ± 1 vs 4 ± 1. L/min) decreased significantly (p< 0.05). All subjects had similar drops on cerebral vascular function. Volume regulating hormone aldosterone increased in both groups (by 119.9% in CONT group and 112.8% in the CM group), but only in the CONT group there were a significant changes (p< 0.05). Angiotensin II was significantly increased by 140.5% after 4-day HDBR in the CONT group (p< 0.05), while no significant changes were observed in the CM group. These results indicated that artificial gravity with ergometric exercise successfully eliminated changes induced by simulated weightlessness in heart rate, volume regulating hormones, and cardiac pumping function and partially maintained cardiac systolic function. Hence, a daily 1. h alternating +1.0 and +2.0. Gz with 40. W exercise training appear to be an effective countermeasure against cardiac deconditioning. © 2011 Elsevier Ltd.

Wen Y.,Chongqing Medical University | Huang Z.,Chinese Astronaut Research and Training Center | Zhang X.,Chongqing Medical University | Gao B.,Chongqing Medical University | He Y.,Chongqing Medical University
International Journal of Clinical and Experimental Medicine | Year: 2015

Objective: A number of studies have investigated the relationship between the PON1 gene polymorphisms and breast cancer risk, but the conclusions are not consistent. In this paper, a meta-analysis was conducted to explore the possible reasons for these inconsistencies, expecting to further clarify the correlation between PON1 gene polymorphisms and breast cancer risk. Methods: After searches in the database such as MEDLINE, EBSCO, ProQuest, Google Scholar, High-Wire, SID (Scientific Information Database) and PubMed, 7 literatures were collected. RevMan 5.2 software was used to perform the meta-analysis. Random-effects or fixed-effects model was used to analyze the odds ratio (OR) and 95% confidence intervals. Results: The analysis of L55M single nucleotide polymorphisms (SNPs) showed that M allele frequency was positively correlated with the incidence risk of breast cancer (OR=1.34, 95% CI: 1.03-1.74). While we did not found Q192R polymorphism associated with the risk of breast cancer (OR=1.0, 95% CI: 0.71-1.42). Conclusion: For PON1 gene, the frequencies of M allele were associated with the incidence risk of breast cancer. © 2015 E-Century Publishing Corporation. All rights reserved.

Wan J.,CAS Institute of Microelectronics | Jia X.,CAS Institute of Microelectronics | Jia X.,Chinese Astronaut Research and Training Center | Yang J.,CAS Institute of Microelectronics | Wang S.,CAS Institute of Microelectronics
IEEE Transactions on Plasma Science | Year: 2010

A stable plasma sheet with an area of 250 × 300mm2 was generated between two different pairs of electrode models, a pair of hollow electrodes discharge model, a single hollow cathode, and a metal plate anode discharge model, by direct current discharge under an axial magnetic field. The electron density distribution across the sheet plasmas in the two different discharge models were compared by the measurements using Langmuir probe. The results showed that the electric field configuration of the pair of hollow electrodes discharge model was more effective to confine the electrons and showed higher electron density in the sheet plasma. The microwave return loss of the sheet plasma had been studied by using a microwave scale network analyzer and the sheet plasma exhibited almost the same reflection capability with an aluminum plate in a microwave range of 2.2 to 4 GHz, which indicated that the sheet plasma with high electron density could be used to reflect electromagnetic wave, and hopefully replace metal plate antenna. © 2010 IEEE.

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