Nuclear factor-E2-related factor 2(Nrf2)is a member of C′n′C transcription factor family.It is an important transcrip-tion factor for regulation of cellular redox status and can be seen in all kinds of tissues .Recent studies have demonstrated that rapid deg-radation of Nrf2 after gene-induced antioxidative stress is as important as transcription and activation of Nrf 2 and the nuclear export of Nrf2 is a prerequisite for rapid degradation of Nrf2 in the cytosol.This review focuses on the mechanism of nuclear export of Nrf 2.

Objective To establish the model of serum-caused damage to pulmonary microvascular endothelial cells (PMVECs) of mice with renal ischemia-reperfusion (I/R) injury.Methods Mice PMVECs were cultured to measure the standard trans-endothelial electrical resistance (TER) in the monolayer of PMVECs.When PMVECs were cultured and arranged in compact monolayer and TER was achieved,they were divided into 4 groups (n =3 each) using a random number table:serum of normal mice group (NS group) and different concentrations (5％,10％ and 20％) of serum of mice with renal I/R injury groups (IRS5 group,IRS10group and IRS20 group).The PMVECs were cultured for 1 h in the serum-free endothelial culture medium.The 0.8 and 0.2 ml culture medium containing 20％ serum of normal mice were then added to the upper and lower chambers,respectively,in group NS.The 0.8 and 0.2 ml culture medium containing 5％,10％ and 20％ serum of mice with renal I/R injury were then added to the upper and lower chambers in IRS5,IRS10 and IRS20 groups,respectively.100 μg/ml FITC-BSA 100 μl was added to the upper chamber in the four groups.At 3,6,9,12,15,18,21 and 24 h of incubation,the PMVEC monolayer permeability (apparent permeability coefficient,Pa) was detected.Results Compared with NS group,the Pa was significantly increased at 12 and 15 h of incubation in IRS5 group,and the Pa was increased at 6-24 h of incubation in IRS10 and IRS20 groups.Compared with IRS5 group,the Pa at 21 and 24 h in IRS10 group and at 9-24 h in IRS20 group were significantly increased.Conclusion Both 10％ and 20％ serum of mice with renal I/R injury can successfully establish the model of damage to PMVECs,and 20％ serum causes a more severe damage.

Objective To evaluate the role of Src kinase in liver injury in endotoxemic mice.Methods Forty-eight female BABL/c mice,aged 3-4 months,weighing 15-20 g,were randomly divided into 3 groups (n =16 each) using a random number table:control group (C group),endotoxemia group (lipopolysaccharide (LPS) group) and Src kinase inhibitor PP2 group (PP2 group).Endotoxemia was induced by intraperitoneal LPS 20 mg/kg in LPS and PP2 groups,while the equal volume of PBS was given in group C.In PP2 group,PP2 1 mg/kg was injected intraperitoneally at 2 h after LPS administration.At 6 h after LPS or PBS injection,8 mice in each group were chosen,and blood samples were collected from the abdominal aorta for determination of the serum levels of alkaline phosphatase (ALP).The mice were then sacrificed and livers were removed for determination of nuclear factor E2-related factor 2 (Nrf2) level,superoxide dismutase (SOD) activity,malondialdehyde (MDA) content and myeloperoxidase (MPO) activity in liver tissues.The other 8 mice in each group were sacrificed at 24 h after LPS or PBS injection,and the livers were harvested for examination of pathological changes.Results Compared with C group,the serum levels of ALP and MDA content and MPO activity in liver tissues were significantly increased,and SOD activity and Nrf2 levels in liver tissues were decreased in LPS and PP2 groups.Compared with LPS group,the serum levels of ALP and MDA content and MPO activity in liver tissues were significantly decreased,and SOD activity and Nrf2 levels in liver tissues were increased in PP2 group.The pathological changes of liver tissues were significantly attenuated in PP2 group as compared with LPS group.Conclusion Src kinase is involved in endotoxemia-induced liver injury in mice.

Objective To evaluate the effect of the serum of rats with hepato-pulmonary syndrome (HPS) on the expression of caveolin-1 and VE-cadherin in pulmonary microvascular endothelial cells (PMVECs).Methods Among the 40 healthy Sprague-Dawley rats,aged 3-4 months,weighing 220-250 g,20 rats were taken randomly for establishment the model of HPS which was produced by chronic ligation of the common bile duct,and the left 20 rats served as sham operation group.Primary PMVECs were harvested from healthy adult Sprague-Dawley rats and inoculated in ECM culture medium or on 96-well culture plate.The PMVECs of 4th-9th generation were randomly divided into 2 groups (n =36 each):control group (group C) and HPS group.In group C,the serum obtained from normal rats in sham operation group was added to PMVECs,while the serum obtained from rats with HPS was added in HPS group.The final concentration of serum was 10％.After being incubated for 12,24 and 36 h (T1-3),the expression of caveolin-1 and VE-cadherin in PMVECs was detected by Western blot,and the PMVEC adhesion rate and proliferation were determined by CKK-8 method.Results Compared with group C,the expression of caveolin-1 and VE-cadherin was significantly down-regulated,the cell adhesion rate was decreased,and the proliferation of PMVECs was enhanced in HPS group.Conclusion The serum of rats with HPS induces weakened PMVEC contact inhibition through down-regulating caveolin-1 and VE-cadherin expression.

Objective To investigate the effects of methionine restriction(MR)on macrophages in lipopolysaccharide(LPS)-induced acute lung injury(ALI)and to explore the underlying mechanism.Methods According to the random number table method,36 male C57BL/6J mice(6～8 weeks old,23±2 g)were divided into 3 groups with 12 mice in each group:the sham group,the LPS group and the LPS+MR group.HE staining and pathological scoring of lung injury were performed in lung tissues.The expression of LPS-binding protein(LBP)and Toll-like receptor-4(TLR4)was detected by RT-qPCR and Western blotting.Macrophage-colony stimulating factor(M-CSF),granulocyte-macrophage-colony stimulating factor(GM-CSF)and chemokine C-C motif ligand 3(CCL3)which are all macrophage-associated chemokines were analyzed by immunohistochemistry.Results Compared with the sham group,the pathological score of lung injury in the LPS group was significantly increased(P＜0.01);The mRNA and protein expression levels of LBP and TLR4 were significantly increased;The number of positive cells of CD11b,F4/80,M-CSF,GM-CSF and CCL3 were significantly increased(P＜0.01).MR significantly improved LPS-induced ALI,and decreased the pathological score of lung injury(P＜0.01);The mRNA and protein expression levels of LBP and TLR4 were decreased;Compared with the LPS group,the number of positive cells of CD11 b,F4/80,M-CSF,GM-CSF and CCL3 were reduced in the LPS+MR group(P＜0.01).Conclusion MR could attenuate LPS-induced ALI by inhibiting the expression of macrophage chemokines and preventing infiltration and activation of macrophage to lungs.

Objective:To evaluate the effects of biorhythm factors on the occurrence of acute kidney injury (AKI) after cardiac surgery using cardiopulmonary bypass.Methods:This was a retrospective cohort study. Data from patients undergoing heart surgery involving cardiopulmonary bypass from June 2018 to December 2019 were collected and divided into 2 groups ( n=125 each) based on the time of anesthesia operation: morning rhythm group (group Ⅰ) and afternoon rhythm group (group Ⅱ). Anesthesia operation was performed from 8: 00 to 12: 00 in group Ⅰ. Anesthesia was performed from 14: 00 to 18: 00 in group Ⅱ. The occurrence of postoperative AKI and other postoperative complications (pulmonary infection, sepsis, cerebral infarction) was recorded. Results:Compared with group Ⅱ, the incidence of postoperative AKI was significantly increased, the relative risk was 3.2 (95% confidence interval 1.31-7.70), and no significant change was found in the incidence of pulmonary infection, sepsis and cerebral infarction in group Ⅰ ( P>0.05). Conclusions:Biorhythm factors affect the development of AKI after cardiac surgery using cardiopulmonary bypass, and performing surgeries in the afternoon rather than the morning helps reduce the risk of postoperative AKI.

Objective To investigate the impact and mechanism of efaproxiral (RSR13),a hemoglobin allosteric agent,on lung injury in rats caused by explosion-induced shock waves in plateau areas. Methods Eighty-two healthy male SD rats (8-week-old,transferred from an altitude of 2 880 m to 4700 m within 6 h)were randomly divided into blast injury group and RSR13+blast injury group (intraperitoneal injection of 150 mg/kg RSR132 h before explosion).Sixty rats were positioned at 5 m from the explosion source and divided into 5-m blast injury group (n=30)and 5-m RSR13+blast injury group (n=30). Additionally,16 rats were positioned at 6 m from the explosion source and then assigned into 6-m blast injury group (n=8)and 6-m RSR13+blast injury group (n=8).The left 6 rats served as control (n=6).Survival outcomes of each rat group positioned 5 m from the explosion source were observed over a 24-hour period.HE staining was used to evaluate the pathological score of the surviving rats positioned at 6 m from the explosion source in 24 h after explosion,along with arterial blood gas analysis.The contents of glutathione (GSH),malondialdehyde (MDA ) and superoxide dismutase (SOD ) in the lung tissues were determined by colorimetry.Western blotting was conducted to measure the expression levels of cleaved caspase-3 and occludin in the lung tissue.Results RSR13 pretreatment increased the survival rate immediately after explosion (93.3％ vs 46.7％,P<0.01 )and at 1 h after explosion (86.7％ vs 46.7％,P<0.01 )in plateau areas of 5 m from the explosion source.At high altitude,RSR13 pretreatment reduced the pathological score of lung injury in rats 6 m away from the explosion source (8.27±0.93 vs 13.70±0.78,P<0.01 ),but had no significant effect on the results of arterial blood gas analysis in rats with lung blast injury (P>0.05 ).In addition,RSR13 pretreatment also increased GSH content (40.27±12.47 vs 22.62±10.88 μg/g,P<0.05),but showed no obvious effect on MDA content and SOD activity (P>0.05 ),decreased the protein level of cleaved caspase-3 (P<0.01 )and increased that of occludin (P<0.05 )in the lung tissues.Conclusion RSR13 exerts significant protective effect on lung injury in rats caused by explosion-induced shock waves in high-altitude environment,which may be related to its increasing antioxidant capacity,reducing cell apoptosis and decreasing barrier permeability of lung ventilation.

Objective To explore the anti-depression mechanism of Kai-Xin-San(KXS)via regulation of neurogenesis in hippocampus of depression-like mice.Methods The extracts of KXS were prepared and the anti-depression effects of KXS were evaluated by behavioral tests on chronic unpredictable mild stress(CUMS)induced depression-like mice.Evaluating depression-like behavior in CUMS mice through sucrose preference test,forced swimming test,tail suspension test,and other methods.Neurogenesis in hippocampus were determined by immunofluorescence assay.In addition,effects of KXS on regulating nestin expression and Wnt/b-catenin signaling pathway were explored by western blotting analysis.Amounts of cortisol,corticotropin-releasing factor(CRF),adrenocorticotropic hormone(ACTH),brain-derived neurotrophic factor(BDNF)and nerve growth factor(NGF)were determined by ELISA tests.Mouse primary neural stem cells(NSC)was used to evaluate the effect of KXS on promoting its proliferation by immunofluorescence assay.In addition,effects of KXS on regulating nestin and Wnt/β-catenin signaling pathway were also explored by Western blotting analysis.Results KXS significantly ameliorated the depression-like behaviors in presence of increased sucrose preference rate and decreased immobile time of tail suspension and forced swimming.KXS significantly promoted the neurogenesis in the hippocampus and expressions of nestin,reduced the expressions of cortisol,CRF,ACTH,increased the expressions of BDNF,NGF,and regulated Wnt/β-catenin signaling pathway.KXS also promoted the proliferation of NSCs and expressions of nestin,enhanced the translocation of b-catenin into nucleus,and regulated the expressions of proteins of Wnt/β-catenin signaling pathway.Conclusion KXS promoted neurogenesis in hippocampus and regulated Wnt/β-catenin pathway,which might contribute to its antidepressant effect.

Objective To investigate the beneficial effect of Kai-Xin-San combined with fluoxetine in improving depression-like behaviors on chronic unpredictable mild stress(CUMS)induced depression model mice.Methods The present study aimed to assess the potential of Kai-Xin-San in combination with fluoxetine to ameliorate depression-like behaviors in a CUMS induced mouse depression model.Behavioral tests,such as the sucrose preference test were employed to evaluate the efficacy of the treatment.Additionally,the levels of suppressed stress factors were measured using the ELISA method.The morphology of hippocampal tissue was evaluated using the HE staining method,Nissl Staining and TUNEL staining methods.Furthermore,western blotting analysis was utilized to determine the expression levels of proteins such as Caspase-3,and Caspase-9.Results The co-administration of Kai-Xin-San and fluoxetine resulted in a significant increase in sucrose preference rate in model mice.This effect was comparable to that of fluoxetine alone at the standard clinical dose.Furthermore,the combination treatment up-regulated the levels of suppressed stress factors,reduced the apoptosis of hippocampus induced by depression and regulated the apoptosis signaling pathway in hippocampus.Conclusion The combination of Kai-Xin-San and fluoxetine has been shown to be an effective treatment for depression-like behavior in animal models,resulting in a reduction in the required clinical dosage of fluoxetine.This effect may be attributed to the up-regulation of neurotransmitter expression,inhibition of stress axis activation,and central nervous inflammation.

Objective Evaluation of the effect and mechanism research of Qi-Shen-Yi-Zhi formula on improving learning and memory ability in mice injected with Aβ1-42 in hippocampus.Methods Alzheimer's disease model mice were constructed by injecting β amyloid peptide 1-42 into hippocampus and treated with water extracts of Qi-Shen-Yi-Zhi formula.The cognitive abilities of mice were assessed using Morris water maze and Y maze tests,which measure learning and memory capabilities.HE staining was used to observe the damage and TUNEL method was used to determine apoptosis of hippocampus.Detection of the expression of oxidative factors,inflammatory factors,and related antioxidant proteins and apoptotic proteins in the hippocampal tissue of a mouse model of dementia.Results Both high-dose and low-dose groups of Qi-Shen-Yi-Zhi formula significantly improved cognitive dysfunction in mice injected with Aβ1-42 in hippocampus,and attenuated the damage and apoptosis of the hippocampus.It also inhibited oxidative stress and downregulated the expressions of inflammatory factors IL-6,IL-1β and TNF-a,increased the expression of antioxidant proteins Nrf2 and HO-1,and regulated the expressions of apoptotic proteins Caspase-9,Caspase-3,Bax and Bcl-2.Conclusion Qi-Shen-Yi-Zhi formula improves the learning and memory abilities of mice injected with Aβ1-42 in hippocampus,which might be related to the attenuation of oxidative stress and neuronal inflammation of hippocampus.