Effects of Total Intravenous Anesthesia on Circadian Rhythms in Patients Undergoing Cardiac Transcatheter Closure.

Objective To evaluate the effects of total intravenous anesthesia on the circadian rhythms in the patients undergoing cardiac transcatheter closure. Methods Thirty patients undergoing cardiac transcatheter closure under elective intravenous anesthesia were included in this study.Paired t-tests were performed to compare the mRNA levels of the genes encoding circadian locomotor output cycles kaput(CLOCK),brain and muscle ARNT-1 like protein-1(BMAL1),cryptochrome 1(CRY1),and period circadian clock 2(PER2),the Munich Chronotype Questionnaire(MCTQ)score,and the Pittsburgh Sleep Quality Index(PSQI)score before and after anesthesia.Multiple stepwise regression analysis was performed to screen the factors influencing sleep chronotype and PSQI total score one week after surgery. Results The postoperative mRNA level of CLOCK was higher [1.38±1.23 vs.1.90±1.47;MD(95%CI):0.52(0.20-0.84),t=3.327,P=0.002] and the postoperative mRNA levels of CRY1 [1.56±1.50 vs.1.13±0.98;MD(95%CI):-0.43(-0.81--0.05),t=-2.319,P=0.028] and PER2 [0.82±0.63 vs.0.50±0.31;MD(95%CI):-0.33(-0.53--0.12),t=-3.202,P=0.003] were lower than the preoperative levels.One week after surgery,the patients presented advanced sleep chronotype [3∶03±0∶59 vs.2∶42±0∶37;MD(95%CI):-21(-40--1),t=-2.172,P=0.038],shortened sleep latency [(67±64)min vs.(37±21)min;MD(95%CI):-30.33(-55.28--5.39),t=-2.487,P=0.019],lengthened sleep duration [(436±83)min vs.(499±83)min;MD(95%CI):62.80(26.93-98.67),t=3.581,P=0.001],increased sleep efficiency [(87.59±10.35)% vs.(92.98±4.27)%;MD(95%CI):5.39(1.21-9.58),t=2.636,P=0.013],decreased sleep quality score [1.13±0.78 vs.0.80±0.71;MD(95%CI):-0.33(-0.62--0.05),t=-2.408,P=0.023],and declined PSQI total score [6.60±3.17 vs.4.03±2.58;MD(95%CI):-2.57(-3.87--1.27),t=-4.039,P<0.001].Body mass index(BMI)(B=-227.460,SE=95.475,t=-2.382,P=0.025),anesthesia duration(B=-47.079,SE=18.506,t=-2.544,P=0.017),and mRNA level of PER2(B=2815.804,SE=1080.183,t=2.607,P=0.015)collectively influenced the sleep chronotype,and the amount of anesthesia medicine(B=0.067,SE=0.028,t=2.385,P=0.024)independently influenced the PSQI one week after surgery. Conclusions Total intravenous anesthesia can improve sleep habits by advancing sleep chronotype.BMI,anesthesia duration,and mRNA level of PER2 collectively influence sleep chronotype one week after surgery.The amount of anesthesia medicine independently influences the PSQI total score one week after surgery.

[Excess Oxygen Supply for Different Time Periods Affect Energy Metabolism in Rat Alveolar Epithelial Type â ¡ Cells].

Objective To observe the effect of excess oxygen supply for different time periods on the mitochondrial energy metabolism in alveolar epithelial type Ⅱ cells. Methods Rat RLE-6TN cells were assigned into a control group (21% O2 for 4 h) and excess oxygen supply groups (95% O2 for 1,2,3,and 4 h,res-pectively).The content of adenosine triphosphate (ATP),the activity of mitochondrial respiratory chain complex V,and the mitochondrial membrane potential were determined by luciferase assay,micro-assay,and fluorescent probe JC-1,respectively.Real-time fluorescence quantitative PCR was employed to determine the mRNA levels of NADH dehydrogenase subunit 1 (ND1),cytochrome b (Cytb),cytochrome C oxidase subunit I (COXI),and adenosine triphosphatase 6 (ATPase6) in the core subunits of mitochondrial respiratory chain complexes Ⅰ,Ⅲ,Ⅳ,and Ⅴ,respectively. Results Compared with the control group,excess oxygen supply for 1,2,3,and 4 h down-regulated the mRNA levels of ND1 (q=24.800,P<0.001;q=13.650,P<0.001;q=9.869,P<0.001;q=20.700,P<0.001),COXI (q=16.750,P<0.001;q=10.120,P<0.001;q=8.476,P<0.001;q=14.060,P<0.001),and ATPase6 (q=22.770,P<0.001;q=15.540,P<0.001;q=12.870,P<0.001;q=18.160,P<0.001).Moreover,excess oxygen supply for 1 h and 4 h decreased the ATPase activity (q=9.435,P<0.001;q=11.230,P<0.001) and ATP content (q=5.615,P=0.007;q=5.029,P=0.005).The excess oxygen supply for 2 h and 3 h did not cause significant changes in ATPase activity (q=0.156,P=0.914;q=3.197,P=0.116) and ATP content (q=0.859,P=0.557;q=1.273,P=0.652).There was no significant difference in mitochondrial membrane potential among the groups (F=0.303,P=0.869). Conclusion Short-term excess oxygen supply down-regulates the expression of the core subunits of mitochondrial respiratory chain complexes and reduces the activity of ATPase,leading to the energy metabolism disorder of alveolar epithelial type Ⅱ cells.

[Overwork Affects Extracellular Matrix of Arterial Vessel Wall in Rats].

Objective To explore the effect of overwork (OW) on extracellular matrix of arterial vessel wall in rats. Methods Random number grouping method was employed to assign 18 Sprague-Dawley rats into three groups(n=6):the control group(no special treatment),group OW(forced swimming twice a day for 15 days),and sleep deficiency(SD)+OW group(in addition to forced swimming twice a day,the rats were put on the platforms in water to limit sleep for 15 days).On the 16th day,the abdominal aorta and common carotid artery were collected after blood sampling from heart under deep anesthesia.A part of the abdominal aorta sample was taken for Masson staining of collagen fiber,and Verhoeff-Van Gieson staining was carried out for the elastic fiber of common carotid artery.Image J was employed for the quantitative analysis of collagen fiber and elastic fiber content.The expression of collagen 1(Col-1) protein was quantified by immunohistochemistry and the ultrastructure of vascular matrix was examined by transmission electron microscopy.The other part of the abdominal aorta sample was used to determine the mRNA levels of matrix metalloproteinase(MMP)-1,MMP-2,MMP-9,tissue inhibitor of metalloproteinases-1(TIMP-1),and Col-1 by quantitative real-time polymerase chain reaction. Results Compared with that in control group,the content of collagen fiber in groups OW and SD+OW had no significant change(all P>0.05);the content of elastic fiber in groups OW and SD+OW decreased(all P<0.001) and had no significant difference between each other(P>0.05).The vascular vessel wall of group OW showed slight fiber breakage,while that of group SD+OW presented wormhole-like or spongy fiber fragmentation.The mRNA levels of MMP-1 and MMP-2 in groups OW and SD+OW had no significant difference between each other(P>0.05) but were higher than that in control group(all P<0.001).The mRNA levels of MMP-9 and TIMP-1 had no significant difference among the three groups(all P>0.05).Groups OW and SD+OW had lower mRNA level(all P<0.001) and protein level(all P<0.001) of Col-1 than control group,while the mRNA and protein levels of Col-1 had no significant difference between groups OW and SD+OW(P>0.05). Conclusion OW can reduce the content of Col-1 and elastic fibers in the extracellular matrix of arterial vessels,destroy the elastic lamina of vascular wall,up-regulate the expression of MMP-1 and MMP-2,thereby injuring arterial vessels.

Lung injury induced by short-term mechanical ventilation with hyperoxia and its mitigation by deferoxamine in rats.

BACKGROUND: Long-term mechanical ventilation with hyperoxia can induce lung injury. General anesthesia is associated with a very high incidence of hyperoxaemia, despite it usually lasts for a relatively short period of time. It remains unclear whether short-term mechanical ventilation with hyperoxia has an adverse impact on or cause injury to the lungs. The present study aimed to assess whether short-term mechanical ventilation with hyperoxia may cause lung injury in rats and whether deferoxamine (DFO), a ferrous ion chelator, could mitigate such injury to the lungs and explore the possible mechanism. METHODS: Twenty-four SD rats were randomly divided into 3 groups (n = 8/group): mechanical ventilated with normoxia group (MV group, FiO2 = 21%), with hyperoxia group (HMV group, FiO2 = 90%), or with hyperoxia + DFO group (HMV + DFO group, FiO2 = 90%). Mechanical ventilation under different oxygen concentrations was given for 4 h, and ECG was monitored. The HMV + DFO group received continuous intravenous infusion of DFO at 50 mg•kg- 1•h- 1, while the MV and HMV groups received an equal volume of normal saline. Carotid artery cannulation was carried out to monitor the blood gas parameters under mechanical ventilation for 2 and 4 h, respectively, and the PaO2/FiO2 ratio was calculated. After 4 h ventilation, the right anterior lobe of the lung and bronchoalveolar lavage fluid from the right lung was sampled for pathological and biochemical assays. RESULTS: PaO2 in the HMV and HMV + DFO groups were significantly higher, but the PaO2/FiO2 ratio were significantly lower than those of the MV group (all p < 0.01), while PaO2 and PaO2/FiO2 ratio between HMV + DFO and HMV groups did not differ significantly. The lung pathological scores and the wet-to-dry weight ratio (W/D) in the HMV and HMV + DFO groups were significantly higher than those of the MV group, but the lung pathological score and the W/D ratio were reduced by DFO (p < 0.05, HMV + DFO vs. HMV). Biochemically, HMV resulted in significant reductions in Surfactant protein C (SP-C), Surfactant protein D (SP-D), and Glutathion reductase (GR) levels and elevation of xanthine oxidase (XOD) in both the Bronchoalveolar lavage fluid and the lung tissue homogenate, and all these changes were prevented or significantly reverted by DFO. CONCLUSIONS: Mechanical ventilation with hyperoxia for 4 h induced oxidative injury of the lungs, accompanied by a dramatic reduction in the concentrations of SP-C and SP-D. DFO could mitigate such injury by lowering XOD activity and elevating GR activity.