1.Effects of sevoflurane on expression of Egr-1 and Egr-2 in suprachiasmatic nuclei of sleep-deprived rats
Qianni SHEN ; Jiabao HOU ; Bo ZHAO ; Yang WU ; Lian LIU ; Qingtao MENG ; Zhongyuan XIA
Chinese Journal of Anesthesiology 2017;37(9):1102-1104
Objective To evaluate the effects of sevoflurane on the expression of early growth response gene 1 (Egr-1) and Egr-2 in the suprachiasmatic nuclei (SCN) of sleep-deprived rats.Methods Forty-eight pathogen-free healthy male Sprague-Dawley rats,were divided into 4 groups (n =12 each) using a random number table:control group (group C),sleep deprivation group (group SD),sevoflurane group (group SEV) and sleep deprivation plus sevoflurane group (group SD+SEV).The rats were subjected to sleep deprivation for 96 h in group SD.The rats inhaled 2.5% sevoflurane for 3 h in group SEV.The rats inhaled 2.5% sevoflurane for 3 h after being subjected to sleep deprivation for 96 h in group SD+SEV.The mechanical paw withdrawal threshold (MWT) was measured at 12 h,3 days and 7 days after emergence from anesthesia (T1-3).The animals were sacrificed after blood samples were obtained from the external carotid artery,and the cerebral SCN was removed for determination of Egr-1 and Egr-2 expression by Western blot.Results Compared with group C,the MWT was significantly decreased at T1-3 in SD,SEV and SD+SEV groups,the expression of Egr-1 and Egr-2 in SCN was significantly up-regulated at T1-3 in SD and SD+SEV groups,and the expression of Egr-1 in SCN was significantly up-regulated at T1-3,and the expression of Egr-2 in SCN was up-regulated at T1 in group SEV (P<0.05).Compared with SD and SEV groups,the MWT was significantly decreased at T1-3 in group SD+SEV,and the expression of Egr-1 and Egr-2 in SCN was significantly up-regulated at T1-3 in group SD+SEV (P<0.05).Conclusion The mechanism by which sevoflurane aggravates hyperalgesia is related to up-regulation of Egr-1 and Egr-2 expression in SCN of sleepdeprived rats.
2.Effect of SIRT3 overexpression on hypoxia-reoxygenation injury to hippocampal neurons of mice exposed to high glucose: relationship with SOD2
Lian LIU ; Zhongyuan XIA ; Bingyu LI ; Yanan LI ; Qianni SHEN ; Bo ZHAO
Chinese Journal of Anesthesiology 2021;41(5):621-624
Objective:To evaluate the effect of sirtuin 3 (SIRT3) overexpression on hypoxia-reoxygenation (H/R) injury to hippocampal neurons of mice exposed to high glucose and its relationship with SOD2.Methods:The normally cultured HT22 neurons at the logarithmic phase were selected and divided into 3 groups ( n=12 each) using a random number table method: high-glucose normoxia group (HG group), high glucose+ H/R group (HHR group) and high glucose+ H/R+ SIRT3 overexpression group (HHR+ SIRT3 group). To establish high glucose model, the neurons in 3 groups were cultured in high-glucose culture medium (glucose concentration of 50 mmol/L) for 8 h. In HHR and HHR+ SIRT3 groups, the cells were exposed to glucose-free and hypoxia for 6 h and then cultured in the high-glucose normoxic environment for 24 h to establish the high glucose and HR injury model.In HHR+ SIRT3 group, the neurons were transfected with SIRT3 overexpressed lentivirus.The cell viability was recorded by the cell counting kit-8 assay, reactive oxygen species (ROS) content was detected by flow cytometry, mitochondrial malonaldehyde (MDA) content, superoxide dismutase (SOD) activity, catalase (CAT) activity and adenosine triphosphate (ATP) content were determined by colorimetry, mitochondrial membrane potential (MMP) was detected by JC-1 probe, and the expression of nuclear respiratory factor 1 (NRF1), mitochondrial transcription factor A (TFAM), SIRT3, SOD2 and acetylated SOD2 (ac-SOD2) was detected by Western blot. Results:Compared with HG group, cell viability, SOD activity, CAT activity, ATP content, MMP, NRF1 and the expression of TFAM and SIRT3 were significantly decreased, and ROS content, MDA content and ac-SOD2/SOD2 ratio were increased in group HHR and group HHR+ SIRT3 ( P<0.05). Compared with HHR group, cell viability, SOD activity, CAT activity, ATP content, MMP, NRF1 and the expression of TFAM and SIRT3 were significantly increased, and ROS content, MDA content and ac-SOD2 /SOD2 ratio were decreased in HHR+ SIRT3 group ( P<0.05). Conclusion:SIRT3 overexpression can alleviate hypoxia-reoxygenation (H/R) injury to hippocampal neurons of mice incubated in high glucose medium, and the mechanism is related to activation of SOD2 deacetylation.
3.Regulating effect of REV-ERBα on working memory after laparotomy and its mechanism in rats exposed to sleep deprivation
Jiabao HOU ; Xing WAN ; Qianni SHEN ; Xuke LIU ; Yang WU ; Wenqin SONG ; Zhongyuan XIA ; Bo ZHAO
Chinese Journal of Neuromedicine 2020;19(3):253-259
Objective:To investigate the protective effect of REV-ERBα agonist SR9009 on hippocampal working memory in rats with acute rapid eye movement (REM) sleep deprivation after exploratory laparotomy and its possible mechanism.Methods:Ninety SD rats were randomly divided into control group, sleep deprivation group, exploratory laparotomy group, sleep deprivation+exploratory laparotomy group, and sleep deprivation+exploratory laparotomy+SR9009 group ( n=18). Rats in the sleep deprivation group, exploratory laparotomy group, and sleep deprivation+exploratory laparotomy group were given REM sleep deprivation for 96 h or (and) exploratory laparotomy, respectively. Rats in the sleep deprivation+exploratory laparotomy+SR9009 group accepted exploratory laparotomy after REM sleep deprivation for 96 h, and accepted intraperitoneal injection of 100 mg/kg SR9009 daily from the day after surgery to the 6 th d of surgery. The reversall escape latency of rats was recorded by contrapuntal space exploration training one-5 d after surgery. On the 5 th d of surgery, reversal space exploration experiment was conducted to record the number of times of rats crossing the original platform. Western blotting was used to detect the protein expressions of REV-ERBα and BMAL1 in the hippocampus of rats. The levels of interleukin (IL)-1β and IL-6 in the hippocampus of rats were detected by enzyme-linked immunosorbent assay. Immunofluorescent staining was used to detect the expressions of neuronal nucleoprotein (NeuN) and glial fibrillary acidic protein (GFAP). Results:(1) The escape latency in the sleep deprivation group, exploratory laparotomy group, and sleep deprivation+exploratory laparotomy group was significantly longer than that in the control group on the first, 2 nd, 3 rd, 4 th, 5 th d of surgery ( P<0.05); while the escape latency in the sleep deprivation group and sleep deprivation+exploratory laparotomy group was significantly longer than that in the exploratory laparotomy group ( P<0.05); on the 2 nd, 3 rd, 4 th, 5 th d of surgery, the reversal escape latency in the sleep deprivation+exploratory laparotomy+SR9009 group was statistically shorter than that in the sleep deprivation+exploratory laparotomy group ( P<0.05). The number of times of rats crossing the original platform in the sleep deprivation group, exploratory laparotomy group, and sleep deprivation+exploratory laparotomy group was significantly smaller than that of the control group ( P<0.05); that of rats in the sleep deprivation+exploratory laparotomy group was significantly smaller than that of the exploratory laparotomy group, and that of rats in the sleep deprivation+exploratory laparotomy+SR9009 group was significantly larger than that of the sleep deprivation+exploratory laparotomy group ( P<0.05). (2) As compared with the control group, the exploratory laparotomy group, sleep deprivation group and sleep deprivation+exploratory laparotomy group had significantly decreased expressions of REV-ERBα and BMAL1, and statistically increased IL-1β and IL-6 levels in the hippocampal tissues ( P<0.05); as compared with the sleep deprivation+exploratory laparotomy group, the sleep deprivation+exploratory laparotomy+SR9009 group had significantly increased expressions of REV-ERBα and BMAL1, and statistically decreased IL-1β and IL-6 levels ( P<0.05). (3) As compared with the control group, the exploratory laparotomy group, sleep deprivation group and sleep deprivation+exploratory laparotomy group had decreased amount of neurons in the hippocampal CA3 area and increased amount of activated astrocytes; as compared with the sleep deprivation+exploratory laparotomy group, the sleep deprivation+exploratory laparotomy+SR9009 group had increased amount of neurons in the hippocampal CA3 area and decreased amount of activated astrocytes. Conclusion:Acute REM sleep deprivation can lead to work memory impairment in rats accepted exploratory laparotomy, which might be associated with neuroinflammation and REV-ERBα/BMAL1 pathway, and SR9009 could alleviate the damage.
4.Production of L-citrulline by a recombinant Corynebacterium crenatum SYPA 5-5 whole-cell biocatalyst.
Qianni LIU ; Meijuan XU ; Rongzhen ZHANG ; Meizhou WANG ; Xian ZHANG ; Taowei YANG ; Zhiming RAO
Chinese Journal of Biotechnology 2017;33(11):1889-1894
Arginine deiminase (ADI) was first high-efficient expressed in Corynebacterium crenatum SYPA 5-5. The ADI was purified by Ni-NTA affinity chromatography and SDS-PAGE analysis showed the molecular weight (MW) was 46.8 kDa. The optimal temperature and pH of ADI were 37 ℃ and 6.5 respectively. The Michaelis constant was 12.18 mmol/L and the maximum velocity was 0.36 μmol/(min·mL). Under optimal conditions, 300 g/L of arginine was transformed and the productivity reach 8 g/(L·h). The recombinant strain was cultivated in a 5-L fermentor and used for whole-cell transformation of 300 g/L arginine, under repeated-batch bioconversion, the cumulative production reached 1 900 g/L.