1.Identification of role of PI3K in mediating necroptosis of L929 cells induced by tumor necrosis factor alpha
Xixi CHANG ; Shiping HU ; Yu WANG ; Lili WANG ; Shuai WU ; Zicheng WANG ; Zhiyan DU ; Jiyun YU ; Yi ZHANG ; Guozhu CHEN
Military Medical Sciences 2017;41(1):25-32
Objective To identify the role of phosphatidylinositol-3-kinase(PI3K) in mediating necroptosis induced by tumor necrosis factor alpha (TNFα) and the involved mechanism.Methods Knockdown of p110α,receptor-interacting protein 1(RIP1) or both p110αand RIP1 was mediated by the specific short hairpin RNA (shRNA) lentivirus and verified by RT-PCR or Western blotting .In addition , Western blotting was used to detect phosphorylation of mixed lineage kinase domain-like protein(MLKL) and protein kinase B(AKT) or tetramerization of MLKL.Cell death was measured by micros-copy and flow cytometry.Results AKT phosphorylation and TNFα-induced necroptosis of L929 cells were suppressed by the inhibitors of PI3K or AKT, as well as p110αknockdown.Moreover, RIP1 knockdown did not inhibit L929 cell death induced by TNFαplus Z-VAD, but the RIP1-independent necroptosis was inhibited by p 110αknockdown.In addition, p110αknockdown suppressed MLKL phosphorylation and tetramerization induced by TNFαwith Z-VAD in L929 cells. Conclusion PI3K mediates necroptosis of L929 cells induced by TNFαby activating AKT and MLKL, respectively.
2.Quantitative proteomic analysis of S-nitrosated proteins in diabetic mouse liver with ICAT switch method.
Xu ZHANG ; Bo HUANG ; Xixi ZHOU ; Chang CHEN
Protein & Cell 2010;1(7):675-687
In this study we developed a quantitative proteomic method named ICAT switch by introducing isotope-coded affinity tag (ICAT) reagents into the biotin-switch method, and used it to investigate S-nitrosation in the liver of normal control C57BL/6J mice and type 2 diabetic KK-Ay mice. We got fifty-eight S-nitrosated peptides with quantitative information in our research, among which thirty-seven had changed S-nitrosation levels in diabetic mouse liver. The S-nitrosated peptides belonged to forty-eight proteins (twenty-eight were new S-nitrosated proteins), some of which were new targets of S-nitrosation and known to be related with diabetes. S-nitrosation patterns were different between diabetic and normal mice. Gene ontology enrichment results suggested that S-nitrosated proteins are more abundant in amino acid metabolic processes. The network constructed for S-nitrosated proteins by text-mining technology provided clues about the relationship between S-nitrosation and type 2 diabetes. Our work provides a new approach for quantifying S-nitrosated proteins and suggests that the integrative functions of S-nitrosation may take part in pathophysiological processes of type 2 diabetes.
Amino Acid Sequence
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Animals
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Computational Biology
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Diabetes Mellitus, Experimental
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metabolism
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pathology
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Female
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Isotope Labeling
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Liver
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chemistry
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pathology
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Mice
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Mice, Inbred C57BL
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Molecular Sequence Data
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Nitrosation
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Peptides
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analysis
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Proteome
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chemistry
3.Discriminante analysis of risk factors Nomograms of myopia in children and adolescents in Yunnan Province
Chinese Journal of School Health 2023;44(9):1387-1391
Objective:
To explore the related factors of myopia among children and adolescents in Yunnan Province, and to predict and evaluate the influencing factors, so as to provide a scientific theoretical basis for the prevention and control of myopia.
Methods:
From March 9 to 14, 2023, 848 students from 6 primary and secondary schools in Dali and Lijiang of Yunnan Province were selected by multi stage stratified random cluster sampling method for visual acuity detection and questionnaire survey on myopia related factors. Multivariate Logistic regression analysis was used to establish a Nomogram prediction model for the selected influencing factors.
Results:
The overall myopia rate of the respondents was 68.3%, the myopia rate of boys (63.4%) was lower than that of girls (72.9%), and the myopia rate of primary school students (46.7%) was lower than that of junior high school students (81.1%), and the difference was statistically significant( χ 2=8.71, 108.07, P <0.05). Daily eye exercises, activities outside the teaching building during recess, having daily sleep time of 7-9 and >9 h, having both parents without myopia were negatively correlated with the occurrence of myopia in children and adolescents in Yunnan Province ( OR=0.64, 0.63, 0.56, 0.28, 0.48, P < 0.05 ). The reading and writing time after school ≥3 h per day and parents unrestricted time to play video games were positively correlated with myopia ( OR=1.94, 1.78, P <0.05). Based on the influencing factors, a Nomogram prediction model was established to quantitatively evaluate the risk of myopia. The results showed that greater risk for myopia was associated with sleep duration, parental history of myopia, and the time spent reading and writing after school every day.
Conclusion
Both genetic factors and environmental factors are related to myopia in children and adolescents. The prediction model of nomogram is beneficial for screening high risk factors of myopia and taking corresponding prevention and treatment measures.
4.Bosentan ameliorates hypertension in rats exposed to chronic intermittent hypoxia through inhibiting renal sympathetic nerve activity.
Sheng-Chang YANG ; Ya-Jing GUO ; Fu-Yang YU ; Ling-Ling CHEN ; Wen-Ya LI ; En-Sheng JI
Acta Physiologica Sinica 2018;70(4):354-360
The purpose of this study is to investigate the effect of the oral endothelin antagonist Bosentan on blood pressure and renal sympathetic nerve activity (RSNA) in rats exposed to chronic intermittent hypoxia (CIH), and to explore the sympathoexcitation mechanism of endothelin-1 (ET-1) in CIH-induced hypertension. Twenty-four male SD rats were randomly divided into normoxia, CIH and Bosentan groups. Rats in the normoxia group were exposed to normoxic environment, and rats in CIH or Bosentan group were exposed to intermittent hypoxia for 3 weeks. Bosentan was given at 50 mg/kg by intragastric administration before intermittent hypoxia exposure in Bosentan group. Systolic blood pressure (SBP) was measured by BP-2000, and the change of RSNA to sodium nitroprusside (SNP) or phenylephrine (PE) was recorded by PowerLab signal acquisition system. Serums of all rats were collected and the contents of ET-1 and norepinephrine (NE) were measured by ELISA. Results showed that blood pressure was gradually increased following CIH exposure compared with the normoxia group during the 3 weeks (P < 0.01, P < 0.01, P < 0.001). The basal RSNA was increased and baroreflex sensitivity was decreased in rats exposed to CIH. Furthermore, the blood pressure was positively correlated with the level of ET-1 in serum in rats exposed to CIH (r = 0.833, P = 0.01). Bosentan administration significantly decreased SBP and basal RSNA, increased the baroreflex sensitivity, and decreased serum NE level in rats exposed to CIH. These results suggest that ET-1 is related with blood pressure elevation in rats exposed to CIH, and Bosentan reverses CIH-induced hypertension by decreasing RSNA.