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Objective:To explore the molecules mechanism of Pin1 in severe heat stroke induced acute lung injury by observing Pin1 regulate oxidative stress and apoptosis formation in pulmonary microvascular endothelial cells (PMVECs) and lung tissue in heat stressed mice.Methods:In vitro, a PMVECs heat stress (HS) model was established. In the control group, PMVECs were placed in a standard 37 °C, 5% CO 2 cell incubator; in the HS group, PMVECs were placed in a 43 °C cell incubator for 2 h, then the cells were further incubated at 37 °C for 1, 3, 6 or 12 h. PMVECs were pretreated with Pin1 inhibitor Juglone (1 μmol/L) 1 h before 43 °C of HS. In vivo, a severe heat stroke mouse model was established. In the HS group, the mice were kept at the simulation of climate chamber with temperature (35.5±0.5) °C, humidity (60±5)%, the rectum temperature in mice was measured by the anal rectal temperature table, when the temperature reached 42 °C, the heat exposure was stopped, and the mice were sacrificed at 1, 3, 6 or 12 h after HS. In the control group, the mice were kept at room temperature (25±0.5) °C. Mice received daily intraperitoneal administration of Pin1 inhibitor Juglone (1 mg/kg) for 3 d before HS. The protein level of Pin1, cleaved caspase-9 and cleaved caspase-3 were analyzed by Western blot, the level of O 2-˙ in cells was observed by DHE staining and fluorescence microscopy, the levels of malondialdehyde (MDA) and the activity of superoxide dismutase (SOD) in lung tissue were measured by ELISA, the pathological changes of mice in different group were detected by HE staining, and the expression of Pin1 in the lung tissue of different groups was detected by immunohistochemical staining, the apoptosis rate of the lung tissue in different groups was tested by TUNEL staining. Results:At 1 h after HS, the protein expression of Pin1 in PMVECs and lung tissue began to increase in a rewarming time-dependent manner ( F=771.6, P<0.05; F=1 035, P<0.05). Cleaved caspase-9 protein in PMVECs and lung tissue started to increase at 3 h post-HS, then increased with a rewarming time-dependent manner ( F=729.8, P<0.05; F=1 773, P<0.05). The protein expression of cleaved caspase-3 in PMVECs and lung tissue also started to increase at 3 h after HS and the expression continued to be increased with prolonged rewarming time, and the trend was consistent with cleaved caspase-9 ( F=1 084, P<0.05; F=1 252, P<0.05). In addition, HS induced the increased release of O 2-˙ from PMVECs, HS induced the imbalance of oxidation-antioxidant system in lung tissue of mice after HS which verified by the continuous release of MDA ( F=114.2, P<0.05) and the continuous inhibition of SOD activity ( F=99.15, P<0.05). Compared with the HS group, pretreatment with Pin1 inhibitor Juglone in PMVECs and mice before HS significantly inhibited the protein expression of Pin1, cleaved caspase-9 and cleaved caspase-3 (all P<0.05), pretreatment with Pin1 inhibitor greatly reduced the release of O 2-˙ in PMVECs after HS, and promoted the restore of the oxidation-antioxidant system balance of lung tissue in mice with severe heat stroke. In addition, compared with the HS group, inhibiting the expression of Pin1 significantly decreased HS induced MDA release [(11.53±0.84) nmol/mL vs (9.65±0.69) nmol/mL, t=12.52, P<0.05], promoted the restore of SOD activity [(41.18±3.45) U/mL vs (57.52±4.83) U/mL, t=5.57, P<0.05] and improved the pathological damage of lung tissue as well as decreased the occurrence of apoptosis in post-HS mice. Conclusion:It was confirmed that Pin1 is involved in heat stress induced acute lung injury mainly through mediating oxidative stress response and apoptosis.
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Objective To observe the oxidative stress, integrity of lysosome and apoptosis of intestinal epithelial cells 6 (IEC-6) after heat stress, and explore the pathogenesis of intestinal damage caused by heat stress.Methods In the heat stress groups,the cells were incubated at 43℃ for 1 hour, then, further incubated at 37℃ and 5% CO2 for 0, 1, 3, 6 and 12 hours respectively; in the medicine intervention group, the cells were pretreated with the medicine 1h before heat stress; while in control group, the cells were incubated at 37℃ and 5% CO2. The amount of reactive oxygen species (ROS) was assayed with 2', 7'-dichlorofluorescin diacetate (DCFH-DA) and dihydroethidium (DHE) staining. The stability of lysosome membrane was checked by AO staining. Apoptosis was analyzed by flow cytometry using annexinⅤ-FITC/PI staining, CCK-8 assay was used to assess cellular viability.Results Compared with control group, cell viability decreased and apoptosis increased at 1 h after heat stress, which was the most obvious at 12h after rewarming (P<0.05). While ROS and pale cells increased immediately after heat stress and the increase become the most obvious (P<0.05). The cell viability in E-64 pretreatment group was significantly improved such as apoptosis reduction, compared with heat stress group (P<0.05).Conclusion Heat stress could induce robust increase of ROS, which mediates lysosome damage and results in cell apoptosis, thus suggesting that ROS-lysosome pathway may play an important role in intestinal injury in heat stress.
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Objective To explore the protective effect of propofol on endothelial cells during heat stress and its protective effect to mitochondra. Methods Heat stress model of human umbilical vein endothelial cell was established when cells were incubated at 43℃ for 2h, then further incubted at 37℃, 5%CO2 for 6h. The experimental group was subdivided into six groups, including 37℃ group, 37℃ plus intralipid group (negative control group), 37℃ plus propofol group, 43℃ plus propofol group, 43℃ plus intralipid group, H2O2 plus propofol group (positive control group); Pretreated with 50μmol/L propofol, 0.2ml intralipid or 25μmol/L H2O2 before heat stress at 43℃, while the cells in the control group were incubated at 37℃. Cell viability was tested by CCK-8. ROS, mitochondrial membrane potential and the changes in mitochondrial permeability transition pore were determined by flow cytometry. The level of ATP was detected by fluorescein-luciferase. The changes of caspase-9 and caspase-3 were analyzed by Caspase Activity Assay Kit. Results HUVESs cell viability and damage of mitochondra were significantly decreased after heat stress. Compared with 43℃ heat stress group, pretreatment with propofol induced the recovery of cell viability and the ROS levels were significantly decreased in HUVEC cells (P<0.05). Meanwhile, the number of cells representing the decrease of mitochondrial membrane potential (the proportion of JC-1 monomer) was significantly decreased (P<0.05) by propofol. The average fluorescence intensity of calcein which representing the MPTP changes and intracellular ATP content was significantly increased (P<0.05). In addition, the activation of mitochondrial apoptotic pathway mediated by caspase-9/3 was also inhibited. Conclusions Propofol have anti-oxidative, anti-apoptosis and mitochondria protective effect against endothelial cell injury during heat stress.
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Objective To investigate the relation between the balloon occlusion test ( BOT) and the anatomy of the circle of Willis ( CW) , and to explore the role of balloon occlusion test in the treatment of internal carotid artery permanent occlusion. Methods Selected the clinical data of 49 patients (52 sides) who had BOT in our hospital from October 2009 to June 2015,and analyzed the relationship be-tween the occurrence rate of anterior communicating artery ( AcoA) / posterior communicating artery ( PcoA) and the positive rate of BOT retrospectively. Results The occurrence rate of the AcoA was 97. 9%, and the occurrence rate of PcoA in one side was 82. 7%. Negative rate BOT accounted for 92. 3% and AcoA occurred in all, while the positive rate accounted for 7. 7%, including 2 cases of right superior ar-teria cerebri anterior combined with ipsilateral PcoAs absence, 1 case of left superior arteria cerebri anterior combined with ipsilateral PcoAs absence, and 1 case of AcoA and PcoAs absence. Conclusion Before the permanent occlusion of the internal carotid artery, it’ s necessary to clarify the redistribution of the compensatory way of blood flow in the AcoA-absent cases. Implementing permanent occlusion for cases with complete circle of Willis would cause less ischemic risk.