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111.
Skin aging caused by intrinsic or extrinsic processes characterized with functional proteomics
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Jia‐You Fang Pei‐Wen Wang Chun‐Hsun Huang Mu‐Hong Chen Yun‐Ru Wu Tai‐Long Pan 《Proteomics》2016,16(20):2718-2731
The skin provides protection against environmental stress. However, intrinsic and extrinsic aging causes significant alteration to skin structure and components, which subsequently impairs molecular characteristics and biochemical processes. Here, we have conducted an immunohistological investigation and established the proteome profiles on nude mice skin to verify the specific responses during aging caused by different factors. Our results showed that UVB‐elicited aging results in upregulation of proliferating cell nuclear antigen and strong oxidative damage in DNA, whereas chronological aging abolished epidermal cell growth and increased the expression of caspase‐14, as well as protein carbonylation. Network analysis indicated that the programmed skin aging activated the ubiquitin system and triggered obvious downregulation of 14‐3‐3 sigma, which might accelerate the loss of cell growth capacity. On the other hand, UVB stimulation enhanced inflammation and the risk of skin carcinogenesis. Collectively, functional proteomics could provide large‐scale investigation of the potent proteins and molecules that play important roles in skin subjected to both intrinsic and extrinsic aging. 相似文献
112.
Wu Man Liyuan Zhang Xihua Li Xiaobing Xie Wenfeng Pei Jiwen Yu Shuxun Yu Jinfa Zhang 《Molecular genetics and genomics : MGG》2016,291(4):1749-1767
113.
Hsueh-Tzu Shih Wei-Yu Chen Kwei-Yan Liu Zong-Siou Shih Yi-Jyun Chen Paul-Chen Hsieh Kuan-Lin Kuo Kuo-How Huang Pang-Hung Hsu Ya-Wen Liu Shih-Peng Chan Hsiu-Hsiang Lee Yu-Chen Tsai June-Tai Wu 《PLoS genetics》2016,12(9)
To maintain a particular cell fate, a unique set of genes should be expressed while another set is repressed. One way to repress gene expression is through Polycomb group (PcG) proteins that compact chromatin into a silent configuration. In addition to cell fate maintenance, PcG proteins also maintain normal cell physiology, for example cell cycle. In the absence of PcG, ectopic activation of the PcG-repressed genes leads to developmental defects and malignant tumors. Little is known about the molecular nature of ectopic gene expression; especially what differentiates expression of a given gene in the orthotopic tissue (orthotopic expression) and the ectopic expression of the same gene due to PcG mutations. Here we present that ectopic gene expression in PcG mutant cells specifically requires dBRWD3, a negative regulator of HIRA/Yemanuclein (YEM)-mediated histone variant H3.3 deposition. dBRWD3 mutations suppress both the ectopic gene expression and aberrant tissue overgrowth in PcG mutants through a YEM-dependent mechanism. Our findings identified dBRWD3 as a critical regulator that is uniquely required for ectopic gene expression and aberrant tissue overgrowth caused by PcG mutations. 相似文献
114.
C Luo X Yao J Li B He Q Liu H Ren F Liang M Li H Lin J Peng T F Yuan Z Pei H Su 《Cell death & disease》2016,7(3):e2160
Subarachnoid hemorrhage (SAH) is a devastating disease with high mortality. The mechanisms underlying its pathological complications have not been fully identified. Here, we investigate the potential involvement of the glymphatic system in the neuropathology of SAH. We demonstrate that blood components rapidly enter the paravascular space following SAH and penetrate into the perivascular parenchyma throughout the brain, causing disastrous events such as cerebral vasospasm, delayed cerebral ischemia, microcirculation dysfunction and widespread perivascular neuroinflammation. Clearance of the paravascular pathway with tissue-type plasminogen activator ameliorates the behavioral deficits and alleviates histological injury of SAH. Interestingly, AQP4−/− mice showed no improvements in neurological deficits and neuroinflammation at day 7 after SAH compared with WT control mice. In conclusion, our study proves that the paravascular pathway dynamically mediates the pathological complications following acute SAH independently of glymphatic control.Cerebral aneurysm rupture causes subarachnoid hemorrhage (SAH), which is associated with a high mortality due to its secondary complications, including hemorrhage, hydrocephalus and delayed cerebral ischemia (DCI).1, 2, 3 Therapeutic interventions against the secondary complications, especially DCI, are yet limited, as the pathological mechanism underlying that is not fully understood.2, 3, 4, 5, 6, 7 Current hypotheses of the development of the secondary complications mainly include cerebral vasospasm (CVS) and the microcirculation disturbance, as well as parenchymal arterial lesions, microthrombosis and neuroinflammation.1, 2, 4, 7, 8, 9Previous studies have shown that the blockade of cerebral lymphatic drainage deteriorated the secondary cerebral ischemia after SAH, suggesting that the cerebral lymphatic drainage pathway could be involved in the pathological mechanism of SAH.10, 11 However, the central nervous system (CNS) was considered lack of a conventional lymphatic drainage system in the past. Recently, several studies have shown that the brain has in fact the proper lymphatic system, including sinus-associated lymphatic vessels and the glymphatic system (GS).12, 13, 14, 15 Sinus-associated lymphatic vessels express all of the molecular hallmarks of lymphatic endothelial cells, contain cerebrospinal fluid (CSF) and immune cells, and drain into the deep cervical lymph nodes.12, 13There is a histologically defined space in the brain, the Virchow–Robin space, where the subarachnoid space meets the paravascular space (or perivascular space in somewhere, PVS).16 The GS is a specialized brain-wide anatomic structure locating at the PVS surrounding the brain vasculature, which is ensheathed with the astroglial endfeet and astroglial water channel aquaporin-4 (AQP4).14, 15 The GS facilitates the efficient lymphatic clearance of extracellular solutes and fluid in the brain through astroglial-mediated interstitial fluid bulk flow.14Impairment of GS involves neurological conditions including traumatic brain injuries,17 ischemic stroke18 and aged brain.19 Interestingly, brain imaging study with magnetic resonance imaging reported weakened GS perfusion following acute stroke or SAH.18, 20 However, little is known about whether the GS is involved in the secondary complications of SAH. Here, we examined the potential involvement of GS in SAH-associated pathology progression with in vivo two-photon microscopy and CLARITY technique.21, 22 Our data showed that subarachnoid blood flowed into the brain parenchyma rapidly through the PVS, causing CVS, vasculitis, widespread microinfraction and neuroinflammation in the animal model of SAH and SAH patients. Prevention of CVS with Fasudil23 did not improve the neurological impairment nor alleviated the pathology, while the PVS clearance with tissue-type plasminogen activator (tPA) infusion improved the behavioral recovery and reduced neuroinflammation in the brain. Interestingly, AQP4−/− mice showed no improvements in neurological deficits and neuroinflammation at day 7 after SAH compared with WT control mice. Our study therefore suggested that the paravacular pathway dynamically mediates the pathological complications following acute SAH independently of glymphatic control. 相似文献
115.
116.
Yu-Chen Han Han-Ming Huang Ling Sun Chao-Ming Tan Min Gao Hong Liu Ri-Ning Tang Yan-Li Wang Bei Wang Kun-Ling Ma Bi-Cheng Liu 《PloS one》2016,11(2)
Background
The growing burden of end-stage renal disease (ESRD) has been a great challenge to the health care system of China. However, the exact epidemiological data for ESRD in China remain unclear. We aimed to investigate the epidemiology of ESRD treated by renal replacement therapy (RRT) in Nanjing based on analysing ten-year data of Nanjing three million insurance covered population.Methods
Using the electronic registry system of Urban Employee Basic Medical Insurance (UEBMI), we included all subjects insured by UEBMI in Nanjing from 2005 to 2014 and identified subjects who developed ESRD and started RRT in this cohort.Results
The UEBMI population in Nanjing increased from 1,301,882 in 2005 to 2,921,065 in 2014, among which a total of 5,840 subjects developed ESRD and received RRT. Over the 10-year period, the adjusted incidence rates of RRT in the UEBMI cohort gradually decreased from 289.3pmp in 2005 to 218.8pmp in 2014. However, the adjusted prevalence rate increased steadily from 891.7pmp in 2005 to 1,228.6pmp in 2014. The adjusted annual mortality rate decreased from 138.4 per 1000 patient-years in 2005 to 97.8 per 1000 patient-years in 2014. The long-term survival rate fluctuated over the past decade, with the 1-year survival rate ranging from 85.1% to 91.7%, the 3-year survival rate from 69.9% to 78.3% and the 5-year survival rate from 58% to 65.4%.Conclusion
Nanjing is facing an increasing burden of ESRD with its improvement of medical reform. The ten-year complete registry data on RRT in urban employees in Nanjing provided a unique opportunity to understand the real threat of ESRD confronting China during its process of health care transition. 相似文献117.
118.
BackgroundSingle nucleotide polymorphisms (SNPs) in the estrogen receptor gene (ESR1) play critical roles in breast cancer (BC) susceptibility. Genome-wide association studies have reported that SNPs in ESR1 are associated with BC susceptibility; however, the results of recent studies have been inconsistent. Therefore, we performed this meta-analysis to obtain more accurate and credible results.MethodsWe pooled published literature from PubMed, EMBASE, and Web of Science and calculated odds ratios (ORs) with 95% confidence intervals (CIs) to assess the strength of associations using fixed effects models and random effects models. Twenty relevant case-control and cohort studies of the 3 related SNPs were identified.ResultsThree SNPs of the ESR1 gene, rs2077647:T>C, rs2228480:G>A and rs3798577:T>C, were not associated with increased BC risk in our overall meta-analysis. Stratified analysis by ethnicity showed that in Caucasians, the rs2228480 AA genotype was associated with a 26% decreased risk of BC compared with the GG genotype (OR = 0.740, 95% CI: 0.555–0.987). The C allele of the rs3798577:T>C variant was associated with decreased BC risk in Asians (OR = 0.828, 95% CI: 0.730–0.939), while Caucasians with this allele were found to experience significantly increased BC risk (OR = 1.551, 95% CI: 1.037–2.321). A non-significant association between rs2077647 and BC risk was identified in all of the evaluated ethnic populations.ConclusionRs3798577 was associated with an increased risk of BC in Caucasian populations but a decreased risk in Asians. Rs2228480 had a large protective effect in Caucasians, while rs2077647 was not associated with BC risk. 相似文献
119.
Long Jin Hai-Ying Zhu Qing Guo Xiao-Chen Li Yu-Chen Zhang Guang-Lei Zhang Xiao-Xu Xing Mei-Fu Xuan Qi-Rong Luo Xi-Jun Yin Jin-Dan Kang 《Biotechnology letters》2016,38(9):1433-1441
Objective
To examine the effect of PCI-24781 (abexinostat) on the blastocyst formation rate in pig somatic cell nuclear transferred (SCNT) embryos and acetylation levels of the histone H3 lysine 9 and histone H4 lysine 12.Results
Treatment with 0.5 nM PCI-24781 for 6 h significantly improved the development of cloned embryos, in comparison to the control group (25.3 vs. 10.5 %, P < 0.05). Furthermore, PCI-24781 treatment led to elevated acetylation of H3K9 and H4K12. TUNEL assay and Hoechst 33342 staining revealed that the percentage of apoptotic cells in blastocysts was significantly lower in PCI-24781-treated SCNT embryos than in untreated embryos. Also, PCI-24781-treated embryos were transferred into three surrogate sows, one of whom became pregnant and two fetuses developed.Conclusion
PCI-24781 improves nuclear reprogramming and the developmental potential of pig SCNT embryos.120.
Xiangqian Zhang Xu Zheng Shanwen Ke Haitao Zhu Fang Liu Zemin Zhang Xinxiang Peng Lin Guo Ruizhen Zeng Pei Hou Ziqiang Liu Suowei Wu Meifang Song Jianping Yang Guiquan Zhang 《Plant molecular biology》2016,92(6):701-715
Most environmental perturbations have a direct or indirect deleterious impact on photosynthesis, and, in consequence, the overall energy status of the cell. Despite our increased understanding of convergent energy and stress signals, the connections between photosynthesis, energy and stress signals through putative common nodes are still unclear. Here we identified an endoplasmic reticulum (ER)-localized adenine nucleotide transporter1 (ER-ANT1), whose deficiency causes seedling lethality in air but viable under high CO2, exhibiting the typical photorespiratory phenotype. Metabolic analysis suggested that depletion of ER-ANT1 resulted in circadian rhythm disorders in sucrose synthesis and induced sucrose signaling pathways, indicating that the ER is involved in the regulation of vital energy metabolism in plants. In addition, the defect of ER-ANT1 triggers ER stress and activates the unfolded protein response in plant cells, suggesting ER stress and photorespiration are closely linked. These findings provide an important evidence for a key role of ER-localized ER-ANT1 in convergent energy and stress signals in rice. Our findings support the idea that ATP is a central signal involved in the plant response to a variety of stresses. 相似文献