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81.
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Inhibition of the adenosinergic pathway: the indispensable part of oncological therapy in the future
Huang Yi Gu Zili Fan Yang Zhai Guangxi Zhao Xiaogang Sun Qifeng Shi Yanbin Lin Guimei 《Purinergic signalling》2019,15(1):53-67
Purinergic Signalling - In recent years, immunotherapy has produced many unexpected breakthroughs in oncological therapy; however, it still has many deficiencies. For example, the number of... 相似文献
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Xiao‐Xi Pan Cheng‐Chao Ruan Xiu‐Ying Liu Ling‐Ran Kong Yu Ma Qi‐Hong Wu Hai‐Qing Li Yan‐Jun Sun An‐Qing Chen Qiang Zhao Fang Wu Xiu‐Jie Wang Ji‐Guang Wang Ding‐Liang Zhu Ping‐Jin Gao 《Aging cell》2019,18(4)
Aging is an independent risk factor for vascular diseases. Perivascular adipose tissue (PVAT), an active component of the vasculature, contributes to vascular dysfunction during aging. Identification of underlying cell types and their changes during aging may provide meaningful insights regarding the clinical relevance of aging‐related vascular diseases. Here, we take advantage of single‐cell RNA sequence to characterize the resident stromal cells in the PVAT (PVASCs) and identified different clusters between young and aged PVASCs. Bioinformatics analysis revealed decreased endothelial and brown adipogenic differentiation capacities of PVASCs during aging, which contributed to neointimal hyperplasia after perivascular delivery to ligated carotid arteries. Mechanistically, in vitro and in vivo studies both suggested that aging‐induced loss of peroxisome proliferator‐activated receptor‐γ coactivator‐1 α (PGC1α) was a key regulator of decreased brown adipogenic differentiation in senescent PVASCs. We further demonstrated the existence of human PVASCs (hPVASCs) and overexpression of PGC1α improved hPVASC delivery‐induced vascular remodeling. Our finding emphasizes that differentiation capacities of PVASCs alter during aging and loss of PGC1α in aged PVASCs contributes to vascular remodeling via decreased brown adipogenic differentiation. 相似文献
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Huanhuan Chen Lei Zhang Zhenqiang Wang Haoya Chang Xiaogang Xie Liangzheng Fu Yong Zhang Fusheng Quan 《Molecular reproduction and development》2019,86(7):862-870
Resveratrol (Res) has been reported to be able to improve oocyte vitrification because of its antioxidative properties. The objective of this study was to further assess the positive effect of Res addition on the developmental potential of vitrified mouse oocytes from the perspective of epigenetic alterations. First, 2 μM Res was chosen as the optimal concentration on the basis of its effects on survival and its antioxidative properties. We found that Res addition significantly promoted fertilization (63.8% vs. 42.9%) and blastocyst formation (68.3% vs. 50.2%) after oocyte vitrification. The quality of the derived blastocysts was also higher after Res treatment. Regarding epigenetic aspects, the expression of the important deacetylase SIRT1 was found to decrease significantly upon vitrification, but it was rescued by Res. The abnormal levels of H3K9 acetylation and DNA methylation in vitrified oocytes were restored by Res addition. Moreover, the expression of several imprinted genes was affected by oocyte vitrification. Among them, abnormal Gtl2 and Peg3 expression levels were restored by Res addition. Therefore, the methylation of their imprinted control regions (ICRs) was examined. Surprisingly, the abnormal patterns of Gtl2 and Peg3 methylation in blastocysts developed from vitrified oocytes were both restored by Res addition. Finally, the full‐term embryonic development showed that the birth rate was improved significantly by Res addition (56.2% vs. 38.1%). Collectively, Res was beneficial for the pre‐ and postimplantation embryonic development. Except for the antioxidative activity, Res also played a role in the correction of some abnormal epigenetic modifications caused by oocyte vitrification. 相似文献
87.
Physiological response of riparian plants to watering in hyper-arid areas of Tarim River, China 总被引:1,自引:0,他引:1
The physiological responses and adaptive strategies of Populus euphratica Oliv. (arbor species), Tamarix ramosissima Ldb. (bush species), and Apocynum venetum L. (herb species) to variations in water and salinity stress were studied in the hyper-arid environment of the Tarim River
in China. The groundwater table, the saline content of the groundwater, as well as the content of free proline, soluble sugars,
plant endogenous hormones (abscisic acid (ABA), and cytokinins (CTK)) of the leaves of the three species were monitored and
analyzed at the lower reaches of the Tarim River in the study area where five transects were fixed at 100 m intervals along
a vertical sampling line before and after water release. Saline stress dramatically increased soluble sugar concentration
of the three species. Differences in sugar accumulation were determined among the species at different transects. The free
proline concentration of the leaves of T. ramosissima and P. euphratica showed a proportional decrease with various degrees of elevation of the groundwater table after water release. There was
a least correlation between the soluble sugars and proline stimulation in T. ramosissima. It was strongly suggested that T. ramosissima developed a different strategy to accumulate organic solutes to adapt to the stress environment. The soluble sugars and proline
accumulation responded to the changes of groundwater table independently: the former occurred under salt stress, whereas the
latter was more significant under drought stress. The concentration and the increase in concentration of ABA and CTK involved
in stress resistance of the three species were also determined. This increase in the hormone concentration in P. euphratica was different from that of the other two species. Expressed as a function of increase of ABA concentration in leaves, A. venetum and T. ramosissima showed a different solute accumulation in response to groundwater table. There was a significant correlation between ABA
accumulation and Δ [proline] in A. venetum as well as between ABA accumulation and Δ [sugar] in T. ramosissima.
Translated from Acta Ecologica Sinica, 2005, 25(8): 1966–1973 [译自: 生态学报] 相似文献
88.
Immobilized metal affinity chromatography (IMAC) is a commonly used technique for phosphoproteome analysis due to its high affinity for adsorption of phosphopeptides. Miniaturization of IMAC column is essential for the analysis of a small amount of sample. Nanoscale IMAC column was prepared by chemical modification of silica monolith with iminodiacetic acid (IDA) followed by the immobilization of Fe3+ ion inside the capillary. It was demonstrated that Fe3+-IDA silica monolithic IMAC capillary column could specifically capture the phosphopeptides from tryptic digest of alpha-casein with analysis by MALDI-TOF MS. The silica monolithic IMAC capillary column was manually coupled with nanoflow RPLC/nanospray ESI mass spectrometer (muRPLC-nanoESI MS) for phosphoproteome analysis. The system was validated by analysis of standard phosphoproteins and then it was applied to the analysis of protein phosphorylation in mouse liver lysate. Besides MS/MS spectra, MS/MS/MS spectra were also collected for neutral loss peak. After database search and manual validation with conservative criteria, 29 singly phosphorylated peptides were identified by analyzing a tryptic digest of only 12 mug mouse liver lysate. The results demonstrated that the silica monolithic IMAC capillary column coupled with muRPLC-nanoESI MS was very suitable for the phosphoproteome analysis of minute sample. 相似文献
89.
In this work, a fundamental regulatory role of formate on thuringiensin production by resting cell of Bacillus thuringiensis YBT-032 was investigated. Nicotinamide adenine dinucleotide (NADH) production and formate dehydrogenase activity increased
with formate addition from 0.5 to 2.0 g/L, respectively. However, with the formate addition of 1.5 g/L, the activities of
pyruvate kinase and glucose 6-phosphate dehydrogenase reached a peak and increased by 316 and 150% relative to those of the
control, respectively. In addition, intracellular production of pyruvate, aspartate, citrate and adenine were significantly
enhanced by 75, 66, 32 and 78% as well. An improvement (90%) of thuringiensin production was also successfully obtained. Interestingly
to point out, thuringiensin yield was closely correlative with adenine production, and the linear relationship was also observed.
The results suggest that appropriate formate addition did act as a modulator and facilitate carbon flux in glycolysis and
pentose phosphate pathway to synthesize adenine and thuringiensin via intracellular NADH availability. 相似文献