SIRT1 exerts protective effects against paraquat-induced injury in mouse type II alveolar epithelial cells by deacetylating NRF2 in vitro.

Silent information regulator 2-related enzyme 1 (SIRT1), a protein deacetylase, is known to strongly protect cells against oxidative stress-induced injury. The nuclear factor E2-related factor 2 (NRF2)-antioxidant response element (ARE) antioxidant pathway plays important regulatory roles in the antioxidant therapy of paraquat (PQ) poisoning. In the present study, we investigated whether the SIRT1/NRF2/ARE signaling pathway plays an important role in lung injury induced by PQ. For this purpose, mouse type II alveolar epithelial cells (AECs­II) were exposed to various concentrations of PQ. The overexpression or silencing of SIRT1 was induced by transfecting the cells with a SIRT1 overexpression vector or shRNA targeting SIRT1, respectively. The protein expression levels of SIRT1 and NRF2 were measured by western blot analysis. The superoxide dismutase (SOD) and catalase (CAT) activities, as well as the glutathione (GSH) and malondialdehyde (MDA) levels were measured using respective kits. Heme oxygenase-1 (HO-1) activity was also determined by ELISA. In addition, cell apoptosis was determined by flow cytometry. The protein stability of NRF2 was analyzed using cycloheximide and its acetylation in the cells was also determined. The following findings were obtained: i) SIRT1 overexpression markedly increased NRF2 protein expression; ii) SIRT1 promoted the transcriptional activity of NRF2 and upregulated the expression of the NRF2 downstream genes, SOD, CAT, GSH and HO-1, thus inhibiting the apoptosis of AECs­II; iii) the inhibition of SIRT1 activity further induced the production of malondialdehyde (MDA), which resulted in increased oxidative damage; iv) SIRT1 promoted the stability of NRF2 by regulating the deacetylation and activation of the NRF2/ARE antioxidant pathway. The findings of this study demonstrate that the protective effects of SIRT1 are associated with the activation of the NRF2/ARE antioxidant pathway in lung injury induced by PQ poisoning.

Protective Effects of Growth Arrest-Specific Protein 6 (Gas6) on Sepsis-Induced Acute Kidney Injury.

Acute kidney injury (AKI) is a serious complication of sepsis, which has a high mortality rate. Growth arrest-specific protein 6 (Gas6), the protein product of the growth arrest specific gene 6, has been shown to have an anti-apoptotic effect as well as pro-survival capability. Here, we investigated the effects of Gas6 on sepsis-associated AKI in mice subjected to cecal ligation and puncture (CLP). We found that the administration of rmGas6 significantly reduced serum urea nitrogen and creatinine and improved the survival of septic mice. Furthermore, the renal pathological damage induced by CLP was attenuated by rmGas6 treatment. Finally, rmGas6 reduced the renal tissue apoptotic index and the expression of Bax, while it upregulated the expression of Bcl-2. The data suggest that rmGas6 might be used as a potential therapeutic agent for sepsis-induced AKI.

Cycloartenyl Ferulate Inhibits Paraquat-Induced Apoptosis in HK-2 Cells With the Involvement of ABCC1.

Nephrotoxicity induced by chemicals such as paraquat (PQ) is a common clinical phenomenon; therefore, searching for drugs with renal protective effect is of a great practical significance. Our previous investigation found that cycloartenyl ferulate (CF) can antagonize the cytotoxic effect of PQ, and recent studies also revealed a variety of bioactivities of CF. However, specific molecular mechanisms underlying the protective effect of CF have not been explored yet. HPLC detection of PQ content indicated that CF reduced PQ accumulation in HK-2 cells and thereby improved cell survival. Western blot results showed that both PQ and CF did not affect the expression of ABCB1; however, while PQ suppressed the expression of ABCC1, CF upregulated ABCC1 expression and thereby reversed the inhibitory effect of PQ on ABCC1 expression. Meanwhile, HK-2 cells did not express ABCG2. When the expression of ABCC1 was knocked down with siRNA, the inhibitory effect of CF on intracellular PQ accumulation was blocked. Further flow cytometric analysis showed that while PQ significantly induced the appearance of sub-G1 apoptotic peak in cells, CF evidently inhibited apoptosis. TUNEL-DAPI double-staining also detected that PQ significantly induced the occurrence of DNA fragmentation in cells, whereas CF effectively inhibited the effect of PQ. Further results showed that ABCC1 siRNA effectively abolished the protective effect of CF on PQ-induced apoptosis. Taken together, these data demonstrated that in HK-2 cells, CF could antagonize PQ-induced toxicity with the involvement of regulatiion of ABCC1 protein expression, which provides a new strategy for treatments of nephrotoxicity.

[Functional polymorphism of NRF2 gene promoter -617C/A in lipopolysaccharide-stimulated peripheral blood mononuclear cellular inflammatory response in patients with alcoholic liver disease].

OBJECTIVE: To investigate the influence of NRF2 gene polymorphism at locus -617 on inflammatory response of lipopolysaccharide (LPS)-stimulated peripheral blood mononuclear cells (PBMCs) in patients with alcoholic liver disease (ALD). METHODS: Venous blood samples from 82 patients with ALD were collected and PBMCs were separated using Ficoll density gradient centrifugation. T cell subgroup was detected by flow cytometry. The polymorphisms in NRF2 gene promoter -617C/A was determined by gene sequencing. According to the results of gene sequencing, patients were divided into non-mutation group (genotype CA and AA) and mutation group (genotype CC). After stimulation with LPS, the expression levels of NRF2, tumor necrosis factor (TNF)α, interleukin (IL)-1ß and IL-10 were measured by reverse transcription-PCR (RT-PCR) and enzyme linked immunosorbent assay (ELISA), respectively. RESULTS: Among the 82 patients with ALD, 32 were homozygous for the C allele (CC), 44 heterozygous (CA), and 6 AA. The frequencies of allele C and A were 65.9% and 34.1%, respectively. There were no differences in clinical data, such as liver function and distribution of T cell subsets between the two groups (all P values >0.05) .Under LPS stimulation, the NRF2 mRNA expression in the non-mutation group was significantly higher than that in the mutation group (P < 0.05). The TNFα, IL-1ß mRNA and protein expression in the mutation group were significantly higher than those in the non-mutation group (P < 0.05) and IL-10 mRNA and protein expression of the mutation group was higher than that in the non-mutation group without statistical significance (P > 0.05). CONCLUSION: The gene promoter NRF2-617C mutated to A in LPS-stimulated PBMC of patients with ALD significantly decreases the expression of NRF2 and releases early proinflammatory cytokines.

[Effects of NF-E2-related factor-2 promoter polymorphism on lipopolysaccharide-induced inflammatory responses in macrophages].

OBJECTIVE: To explore the effects of NF-E2-related factor-2 (NRF2)-617C/A promoter polymorphism on NRF2 expression as well as lipopolysaccharide-induced inflammatory responses in macrophages. METHODS: NRF2-617C/A promoter fragments were synthesized by chemical method and cloned into a pUC57 vector. The dul-luciferase reporter assay was employed to determine the activity of promoters. Then recombinant adenoviral vectors were constructed and transfected into macrophages. The expression of Nrf2 was examined by Western blotting and reverse transcription (RT)-PCR. The expressions of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and interleukin-10 (IL-10) in macrophages after the stimulation of LPS were determined by enzyme-linked immunosorbent assay (ELISA). RESULTS: The activity of NRF2-617C promoter-luciferase reporter (FLuc/RLuc activity ratio) was significantly higher than that of NRF2-617A group (0.584 ± 0.016 vs 0.258 ± 0.018, P < 0.05).The NRF2 protein and mRNA levels in -617C group were much higher than those of 617A group (1.123 ± 0.080 vs 0.951 ± 0.057,1.889 ± 0.031 vs 1.647 ± 0.323, both P < 0.05). After the stimulation of LPS, the NRF2 protein expression in macrophages significantly increased (0.584 ± 0.016 vs 0.258 ± 0.018, P < 0.05). Compared with -617A group, there was a significantly higher expression of NRF2 in -617C group (0.671 ± 0.033 vs 0.751 ± 0.014, P < 0.05). Additionally, the productions of IL-6 and IL-10 in -617C group were markedly lower than those in -617A group as well as IL-6/IL-10 (both P < 0.05). However, no significant difference existed in the levels of TNF-α between -617C and -617A groups (P > 0.05). CONCLUSIONS: The -617C/A promoter polymorphism of NRF2 may influence the NRF2 expression. And it appears to be associated with the LPS-induced inflammatory responses in macrophages.

The reversal of paraquat-induced mitochondria-mediated apoptosis by cycloartenyl ferulate, the important role of Nrf2 pathway.

In this study, we demonstrate the protective effects of Cycloartenyl ferulate (CF) against Paraquat (PQ)-induced cytotoxicity and elucidate the underlying molecular mechanisms. The results show that, CF could reverse the PQ-induced growth inhibition and release of lactate dehydrogenase in HK-2 human proximal tubular cells. Treatment with PQ induced apoptosis in HK-2 cells, as evidenced by accumulation of sub-G1 cell population, chromatin condensation, DNA fragmentation, and translocation of phosphatidylserine, which were significantly attenuated by co-incubation with CF. Mitochondria-mediated apoptosis pathway contributed importantly to PQ-induced apoptosis, as revealed by the activation of caspase-3/-9, cleavage of PARP, depletion of mitochondrial membrane potential regulated by Bcl-2 family members, and overproduction of reactive oxygen species, which were also effectively blocked by CF. Moreover, treatments of PQ strongly inhibited the expression of Nrf2 and the downstream effectors, HO1 and NQO1. However, co-treatment with CF effectively reversed this action of PQ. Furthermore, silencing of Nrf2 by the siRNA technique significantly blocked the cytoprotective effects of CF against PQ-induced apoptosis, which suggest the important role of Nrf2 signaling pathway an cell apoptosis induced by PQ. Taken together, this study provides a novel strategy for molecular intervention against PQ-induced nephrotoxicity by using phytochemicals.

[Comparison of sedative effects of propofol and midazolam on emergency critical patients on mechanical ventilation].

OBJECTIVE: To compare the sedative effects of propofol and midazolam, or combination of them on emergency critically ill patients on mechanical ventilation. METHODS: Medical records of 68 patients treated in emergency intensive care unit (EICU) receiving mechanical ventilation and sedation care from August 2007 to July 2011 were reviewed retrospectively. According to the type of sedatives used, patients were assigned to propofol group (n=28), midazolam group (n=20), combination of propofol and midazolam group (combination group, n=20). Patients in the former two groups were given a loading dose of propofol or midazolam and followed by continuous infusion of the same drugs. Those in the combination group were given a loading dose of propofol and followed by continuous infusion of propofol together with midazolam. In this study, Ramsay anesthesia score was used to evaluate the effectiveness of sedation. The patients in three groups were maintained at depth of sedation level 2-4 according to the Ramsay score, and reassessed every 1-2 hours after the initiation. The change in vital signs and respirator related parameters were observed before and after administration in three groups, and the treatment information of sedative and mechanical ventilation were recorded. RESULTS: Heart rate (HR), respiratory rate (RR), systolic blood pressure (SBP), diastolic blood pressure (DBP), tidal volume (VT) were decreased at 1 hour after treatment compared with those before treatment in all the three groups, while the blood oxygen saturation (SpO2) was increased. There were no significant differences in RR and SpO2 at 1 hour after treatment among three groups. HR, SBP, DBP at 1 hour after treatment in propofol group were significantly decreased compared with those in midazolam group and combination group (HR: 20.43 ± 13.52 bpm vs. 15.27 ± 13.71 bpm, 18.54 ± 10.07 bpm; SBP: 39.26 ± 16.64 mm Hg vs. 25.80 ± 21.09 mm Hg, 31.50 ± 28.20 mm Hg; DBP: 21.35 ± 12.91 mm Hg vs. 14.07 ± 10.53 mm Hg, 16.42 ± 13.55 mm Hg, P<0.05 or P<0.01). VT at 1 hour after beginning of the treatment in combination group was decreased significantly compared with propofol group and midazolam group (121.06 ± 96.50 ml vs. 33.36 ± 28.49 ml, 39.94 ± 33.24 ml, both P<0.01). The drug dosage in combination group was decreased significantly compared with propofol group and midazolam group (total dosage of propofol: 25.21 ± 15.33 mg/kg vs. 90.83 ± 17.42 mg/kg, total dosage of midazolam: 2.37 ± 1.87 mg/kg vs. 4.02 ± 3.62 mg/kg, both P<0.01), but there was no significant difference in sedation time among groups. EICU stay days in combination group was shortened significantly compared with propofol group and midazolam group (7.75 ± 5.20 days vs. 12.53 ± 8.24 days, 15.20 ± 8.33 days, both P<0.05), but there was no significant difference in mechanical ventilation duration among groups. CONCLUSIONS: A combination of propofol with midazolam for emergency critically ill patients on mechanical ventilation not only can achieve a good sedative effect, reduce total amount of the drug, but also alleviate the inhibitory effect of propofol on the circulation, improve the symptoms of asynchronous ventilation, and reduce stay time in EICU.

[To evaluate the therapeutic efficacy of hemoperfusion in treating intermediate syndrome following acute organophosphate poisoning].

OBJECTIVE: To evaluate the therapeutic efficacy of hemoperfusion in the treatment of intermediate myasthenia syndrome (IMS) following acute organophosphate poisoning (AOPP). METHODS: Eighty cases of IMS following AOPP, who were admitted to the Emergency Department of our hospital from 2006 to 2011 and had complete clinical records, were divided into HP treatment group (n = 36) and non-HP (NHP) treatment group (n = 44). The therapeutic efficacy of HP was evaluated by comparing the clinical data of the two groups. RESULTS: The HP treatment group showed significantly increased serum cholinesterase activity at 24h and 72 h after admission (P < 0.05), while the NHP treatment group showed significantly increased serum cholinesterase activity at 72 h after admission (P < 0.05). The serum cholinesterase activity in the HP treatment group was significantly higher than that in the NHP treatment group at 24 h after admission (P < 0.05). Compared with the NHP treatment group, the HP treatment group had significantly decreased total atropine dose, time of ventilatory assistance, length of ICU stay, recovery time from coma, incidence of pulmonary infection, and mortality due to respiratory failure (P < 0.05). There were no significant differences in the incidence of upper gastrointestinal hemorrhage and total mortality between the two groups (P > 0.05). CONCLUSION: Hemoperfusion is an effective therapy for improving clinical symptoms, shorten the course of disease, reducing complications, and decreasing the mortality due to respiratory failure in the patients with IMS following AOPP.

Thrombolytic therapy for cardiac arrest due to pulmonary embolism after varicose vein surgery.

Anticoagulant therapy is the mainstay in the management of venous thromboembolism. Nevertheless, the situation is entirely different in the patients with submassive or massive pulmonary embolism (PE) and cardiac arrest, and the diagnosis and therapy strategy for such conditions are lacking. This patient, who presented with a cardiac arrest event after varicose vein surgery, was diagnosed as acute pulmonary embolism. She survived after administration of 50 mg recombinant tissue plasminogen activator (rt-PA) for over half an hour, along with continued anticoagulant therapy. Unfortunately, gastrointestinal and cerebral hemorrhaging occurred during the process.

Curcumin inhibits suppressive capacity of naturally occurring CD4+CD25+ regulatory T cells in mice in vitro.

Accumulating evidence has demonstrated that naturally occurring CD4(+)CD25(+) regulatory T cells (Tregs) are critical for maintenance of immunological tolerance and have been shown to be important in regulating the immune responses in many diseases. Curcumin, a phytochemical obtained from the rhizome of the plant Curcuma longa, has achieved the potential therapeutic interest to numerous immune-related disorders. However, the effect and mechanism of curcumin on Tregs remain largely elusive. In the present study, curcumin inhibition of the suppressive activity of CD4(+)CD25(+) regulatory T cells appears to be dependent on three categories: inhibiting cell-cell contact by down-regulation of CTLA-4, suppressing inhibitory cytokine secretion and decreasing the ability to consume IL-2 and/or suppress IL-2 production. In addition, Foxp3 expression was also reduced on Tregs after curcumin stimulation. Moreover, we found that nuclear translocation of p65 and c-Rel, which is critical for Foxp3 and CD25 expressions, was markedly decreased in Tregs with curcumin stimulation. Based on the role of curcumin in the suppressive activity of Tregs, it may be feasible to use curcumin as an immunotherapy for Treg-related diseases, such as tumors and sepsis.

[Effects of hemoperfusion on oxidative stress, matrix metalloproteinases and their inhibitors in acute paraquat poisoning rabbits].

OBJECTIVE: To observe the effects of hemoperfusion on oxidative stress status and the levels of matrix metallo proteinase (MMP-2, MMP-9), tissue inhibitor of metalloproteinase (TIMP-1) in lungs, livers and kidneys in paraquat poisoning rabbits, and to explore the mechanism of therapeutic effects induced by HP on acute paraquat poisoning. METHODS: Seventy eight rabbits were randomly divided into normal control group (N group, n=6), exposure groups (PQ group, n=24), hemoperfusion treatment group (HP treatment group, n= 24) and blank control group (HP group, n=24). The PQ, HPQ and HP groups were divided into 4 observation time groups (1, 3, 7 and 21 d). N group was exposed to 5 ml normal saline and PQ group was exposed to 50 mg/kg PQ by oral gavage. In 1 h after PQ exposure, HPQ group was exposed to the activated carbon hemoperfusion for 2 h. The content or activity of MDA, SOD and GSH-Px in lungs, livers and kidneys were detected, the expression levels of MMP-2, MMP-9 and TIMP-1 were measured with immunohistochemical SP method for all groups. RESULTS: The contents of MDA in lungs, livers and kidneys of PQ and HPQ groups decreased and the activities of SOD and GSH-Px in lungs, livers and kidneys of PQ and HPQ groups increased with observation time. The expression levels of MMP-2, MMP-9 and TIMP-1 in PQ and HPQ groups enhanced on the first day, PQ group was most obvious. Along with the observation time extended, all kinds of positive expression were still high. Compared with normal control group, the activities of serum SOD and GSH-Px in PQ and HPQ groups declined significantly, but the contents of serum MDA increased; the expression levels of MMP-2, MMP-9 and TIMP-1 in lung, liver and kidney tissues increased obviously, the ration between MMP-9 and TIMP-1 significantly increased (P < 0.05). Compared with PQ group, the activities of SOD and GSH-Px in HPQ group significantly increased, the content of MDA declined, the expression levels of MMP-2, MMP-9 and TIMP-1 in lung, liver and kidney tissues declined obviously, the ration between MMP-9 and TIMP-1 significantly declined, but higher than N group, the differences were statistically significant (P < 0.05). CONCLUSION: The oxidative stress and MMPs may be involved in the pathogenesis of tissue injuries induced by paraquat. The treatment with HP could obviously reduce oxidative stress and the expression levels of MMP-2, MMP-9 and TIMP-1, enhance the ration between MMP-9 and TIMP-1. So HP treatment could play a role in rescuing the PQ poisoning and protecting the organs function.

[Effect of ulinastatin on oxidative stress and nuclear factor E2-related factor 2 expression in the lung tissues of acute hydrogen sulfide intoxicated rats].

OBJECTIVE: To investigate the dynamic changes of oxidative stress and nuclear factor-E2 related factor 2 (Nrf2) expression in the lung tissues of acute hydrogen sulfide (H2S) intoxicated rats and intervention effects of ulinastatin (UTI). METHODS: A total of 96 SD rats of clean grade were divided randomly into four groups: normal control group (n = 8), UTI control group (n = 8), H2S -intoxicated model group (n = 40), and UTI treatment group (n = 40). The H2S-intoxicated model group and UTI treatment group were exposed to H2S (283.515 mg/m3) by inhalation for 1h, then UTI treatment group was intraperitoneally exposed to UTI at the dose of 10(5) U/kg for 2 h. H2S-intoxicated model group and UTI treatment group were sacrificed at 2, 6, 12, 24 and 48 h after exposure, respectively. The levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione (GSH) in the rat lung tissues were measured. The expression levels of Nrf2 mRNA in the rat lung tissues were detected. Pathological changes of rat lung tissues were observed under a light microscope and the lung injury scores were evaluated. RESULTS: Compared with control group, the pulmonary SOD, CAT and GSH levels at 2,6 and 12 h after exposure and the pulmonary GSH-Px levels at 2, 6, 12 and 24 h after exposure in H2S-intoxicated model group significantly decreased (P < 0.05 or P < 0.01). The levels of pulmonary MDA at 2, 6, 12 and 24 h after exposure in H2S-intoxicated model group were significantly higher than those in normal control group (P < 0.01). As compared with H2S -intoxicated model group, the pulmonary GSH-Px activities at 6 and 12 h after exposure, the pulmonary CAT activities at 2, 6 and 12 h after exposure, the pulmonary GSH levels at 2, 6, 12 and 24 h after exposure and the pulmonary SOD activities at 2, 6, 12, 24 and 48 h after exposure in UTI treatment group significantly increased (P < 0.05 or P < 0.01), the pulmonary MDA levels at 2, 6 and 12 h after exposure in UTI treatment group significantly decreased (P < 0.01). The expression levels of Nrf2 mRNA at 2, 6, 12, 24 h after exposure in H2S-intoxicated model group were 0.314 +/- 0.011, 0.269 +/- 0.010, 0.246 +/- 0.011 and 0.221 +/- 0.018, respectively, which were significantly higher than those (0.149 +/- 0.012) in control group (P < 0.01). As compared with H2S-intoxicated model group, the expression levels (0.383 +/- 0.017, 0.377 +/- 0.014, 0.425 +/- 0.017, 0.407 +/- 0.011 and 0.381 +/- 0.010) of Nrf2 mRNA at 2, 6, 12, 24 and 48 h after exposure in UTI treatment group significantly increased (P < 0.01). The lung injury at 24 h after exposure in H2S-intoxicated model group was higher than that in UTI treatment group. Histopathological examination showed that the scores of lung injury at 12, 24 and 48 h after exposure in UTI treatment group was significantly lower than those in H2S-intoxicated model group (P < 0.01). CONCLUSION: Oxidative stress and Nrf2 activation may be the important factors in rat lung injury induced by H2S-intoxicated, UTI may reduce the rat lung injury and protect the rat lung from damage induced by H2S by inhibiting ROS, improving the imbalance in redox and up-regulating Nrf2 mRNA expression.

Surgical treatment of 19 cases with vibrio necrotising fasciitis.

BACKGROUND: Necrotising fasciitis and sepsis caused by the infection of vibrio is a rare but dangerous clinical emergency, with a mortality of 50-100%. Early diagnosis and surgical treatment may improve the prognosis significantly. However, valid emergency operation indications are scarce and need to be explored, which will be helpful for the early recognition and selection of operational procedures in patients with vibrio necrotising fasciitis. METHODS: We retrospectively analysed the patients with vibrio necrotising fasciitis admitted to the emergency department of our hospital from July 2000 to June 2009. The surgical treatment strategy was summarised in order to provide clinical evidence for surgical treatment of vibrio necrotising fasciitis. RESULTS: A total of 19 cases of vibrio necrotising fasciitis were selected in our study. All the patients were living along the coast, and 68.4% had a history of chronic liver disease, 78.9% had a history of ethanol abuse, 52.6% had fever, 89.5% were complicated with septic shock and 31.6% progressed to multiple-organ dysfunction syndrome. Rapidly progressive local swelling and pain as well as skin superficial venous stasis were the early presentations of vibrio necrotising fasciitis, while skin ecchymosis, blisters or blood blisters, necrosis and subcutaneous crepitation were the presentations of the advanced stage. Seventeen patients received emergency incision and drainage, subcutaneous vein thrombosis, subcutaneous tissue necrosis, muscle and full-thickness necrosis observed in the operation, and necrotising fasciitis was confirmed by exploration or pathologic examination. Selective debridement and skin graft was performed to repair the wound after operation, and amputation was performed on two patients to close the wound. The average length of stay was 21.3 days (1-82 days), and eight patients died, with mortality being 42.1%. CONCLUSION: Rapidly progressive local damage and acute deterioration of the patients are the most distinctive clinical manifestations of vibrio necrotising fasciitis. Recognition of the signs of local skin and tissue damage in early stage is crucial for early diagnosis and surgical intervention. Emergency incision and drainage, combined with selective debridement and skin graft, could improve the prognosis of the patients, and preserve the integrity of the patient's limbs as much as possible.

[The effects of NF-E2-related factor-2 prompter polymorphism on alcoholic liver disease with Vibrio vulnificus sepsis].

OBJECTIVE: To investigate the influence of genetic polymorphism in NF-E2-related factor-2 (nrf2) gene promoter locus at 336 in alcoholic liver disease (ALD) with Vibrio vulnificus (VV) sepsis. METHODS: Through the simple random sampling method, C57B6 male mice were divided into normal feeding group (group A, 10 mice), alcoholic liver disease group (group B, 10 mice), normal feeding group infected with VV through intraperitoneal injection (group C, 8 mice), alcoholic liver disease group infected with VV (group D, 110 mice). Through gene sequencing method, nrf2 gene promoter 336 polymorphism in D group was analyzed and grouped into: non-mutation group (336T) (group D1, 7 mice) and mutation group (336C) (group D2, 10 mice). Through RT-PCR, Western-blotting and ELISA method, expressions of nrf2, tumor necrosis factor-α (TNF-α), interleukin-10 (IL-10), high mobility group protein 1 (HMGB(1)) gene and protein of liver were measured. The pathological changes in liver were recorded with light microscope. RESULTS: After infected with VV for 48 hours for A, B, C, D1, D2 group, the expression medians of nrf2 mRNA in liver were 0.115, 0.173, 0.211, 0.764, 0.352, respectively (χ(2) = 40.64, P < 0.05), the expression medians of IL-10 mRNA in liver were 0.338, 0.637, 1.002, 1.825, 1.403, respectively (χ(2) = 41.05, P < 0.05), the expression medians of TNF-α mRNA in liver were 0.140, 0.254, 0.372, 0.399, 0.699, respectively (χ(2) = 38.16, P < 0.05), the expression medians of HMGB(1) mRNA in liver were 0.230, 0.410, 0.668, 0.508, 1.021, respectively (χ(2) = 31.45, P < 0.05). After infected with VV 48 hours for mice in A, B, C, D1, D2 group, the expression medians of nrf2 protein in liver were 0.908, 1.461, 2.061, 3.982, 2.243, respectively (χ(2) = 33.72, P < 0.05), the expression medians of IL-10 protein in liver were 13.97, 22.54, 30.14, 57.98, 41.53, respectively (χ(2) = 37.31, P < 0.05), the expression medians of TNF-α protein in liver were 114.07, 142.94, 175.44, 174.60, 266.11, respectively (χ(2) = 32.29, P < 0.05), the expression medians of HMGB(1) protein in liver were 2.01, 6.05, 9.62, 6.24, 12.89, respectively (χ(2) = 36.94, P < 0.05). Compared with group A, there were large amount of fat drops, fatty changes in group B, inflammatory cell infiltration, disorder of hepatic cell in group C, and extension of hepatic duct and vein, edema of liver cells and disorder of hepatic cells in group D. CONCLUSION: The nrf2 gene promoter of T336C mutation in C57B6 mouse of ALD can significantly decrease the expression of nrf2, and intensify organ inflammation and damage when they were infected by VV.

[In vitro construction and confirmation of adenovirus containing a mifepristone (RU486)-inducible regulation system for NRF2 gene].

OBJECTIVE: To construct an adenovirus containing a mifepristone (RU486)-inducible regulation system for NRF2 gene, express the product in H460 cell and verify whether the mentioned system can control the gene expression and assess its efficiency. METHODS: A RU486-inducible regulation system for Nrf2 gene was introduced into an adenovirus. The confirmation was performed through the LUC and Dsred genes. And the expression pattern of Nrf2 at the viral level was examined by Western blot and RT-PCR (reverse transcription-polymerase chain reaction). RESULTS: The expressions of LUC and Dsred showed a rising trend with the incremental dose of RU486. After the transfection H460 cell with Ad-RUNrf2, the results of RT-PCR and Western blot demonstrated that the expression of Nrf2 was elevated with a rising dose of RU486. After the removal of RU486, the expression of Nrf2 was reduced. CONCLUSION: The construction of an adenovirus carrying Nrf2 gene regulated by a RU486-inducible system is successful, and RU486 can adjust the cellular expression of Nrf2 factor. The LUC and the Dsred expression assumes the dosage dependence along with RU486 to increase; after the Ad-RUNrf2 infects the H460 cell, through RTPCR and Western the Blot result demonstrated that the expression of Nrf2 increases along with the RU486 dosage increases, after removing RU486, the Nrf2 expression is weaken. Showing the construction of the adenovirus carrying Nrf2 gene regulated by the mifepristone (RU486)-inducible system is successful, and RU486 can adjust the Nrf2 factor in the cell the expression.

Expression of high mobility group protein B1 in the lungs of rats with sepsis.

BACKGROUND: Vibrio vulnificus inside the body could activate the NF-κB signaling pathway and initiate the inflammatory cascade. The lung is one of the earliest organs affected by sepsis associated with acute lung injury. High mobility group protein B1 (HMGB1) is an important late-acting pro-inflammatory cytokine involving in the pathophysiology of sepsis. It is also involved in the injury process in the lung, liver and intestine. There has been no report on the involvement of HMGB1 in Vibrio vulnificus sepsis-induced lung injury. METHODS: Sixty rats were randomly divided into a normal control group (group A, n=10) and a Vibrio vulnificus sepsis group (group B, n=50). Sepsis was induced in the rats by subcutaneous injection of Vibrio vulnificus (concentration 6×10(8) cfu/mL, volume 0.1 mL/100g)) into the left lower limbs. The rats in group B were sacrificed separately 1, 6, 12, 24, and 48 hours after the infection. Their lungs were stored as specimens, lung water content was measured, and lung pathology was observed under a light microscope. The expressions of the HMGB1 gene and protein in the lungs were detected by RT-PCR and Western blot. Data were analyzed with one-way analysis of variance (ANOVA) and the LSD method for pair-wise comparison between the two groups. P<0.05 was considered statistically significant. RESULTS: Compared to group A (0.652±0.177), HMGB1 mRNA expression in the lungs of group B was significantly higher at 0 hour (1.161±0.358, P=0.013), 24 hours (1.679±0.235, P=0.000), and 48 hours (1.258±0.274, P=0.004) (P<0.05), and peaked at 24 hours. Compared to group A (0.594±0.190), HMGB1 protein expression at 6 hours (1.408±0.567, P=0.026) after infection was significantly increased (P<0. 05), and peaked at 24 hours (2.415±1.064, P=0.000) after infection. Compared to group A (0.699±0.054), lung water content was significantly increased at 6 hours (0.759±0.030, P=0.001),12 hours (0.767±0.023, P=0.000), 24 hours (0.771±0.043, P=0.000) and 48 hours (0.789±0.137, P=0.000) after infection (P<0.05). Compared to group A, pathological changes at 12 hours in group B indicate marked pulmonary vascular congestion, interstitial edema and inflammatory infiltration. Alveolar cavity collapse and boundaries of the alveolar septum could not be clearly identified. CONCLUSION: Vibrio vulnificus sepsis can lead to injury in rat lungs, and increased HMGB1 expression in lung tissue may be one of the mechanisms for injury from Vibrio vulnificus sepsis.

[Effects of hemoperfusion on plasma concentration and histopathological changes in paraquat poisoning rabbits].

OBJECTIVE: To observe the effects of hemoperfusion on plasma concentration and histopathological changes in paraquat (PQ) poisoning rabbits. METHODS: Sixteen rabbits were randomly divided into exposure group (PQ group, n = 8) and hemoperfusion plus PQ exposure group (HPQ group, n = 8). HPQ group were given hemoperfusion in 45 min after exposure to PQ. The plasma PQ concentrations at 0.5, 1.0, 1.5, 2.0, 3.0, 6.0, 12.0, 24.0, 48.0 and 72.0 hours after exposure were measure in 2 groups. The histopathological changes of lung, liver and kidney were examined, the behavior changes and the survival number of 7 days were observed. RESULTS: The poisoning symptoms of HPQ group were generally better than those of PQ group, in each group six animals survived for 7d. The plasma PQ concentrations at 1.0, 1.5, 2.0, 3.0, 6.0, 12.0, 24.0, 48.0, 72.0 h after exposure in HPQ group were significantly lower than those in PQ group (P < 0.05 or P < 0.01). In HPQ group, the plasma PQ peak concentration [(5.01 ± 0.15] µg/L], area under the curve [(54.03 ± 5.31) mg×h(-1)×L(-1)] and PQ half-life time [(16.29 ± 3.26) h] after treatment of HP were significantly lower than those [(11.97 ± 0.75) µg/L, (141.40 ± 10.10) mg×h(-1)×L(-1) and (31.16 ± 9.85) h] in PQ group (P < 0.05). The apparent volume of distribution and PQ clearance rate in HPQ group were significantly higher than those in PQ group (P < 0.05). Congestion, edema, cell infiltration and other pathological changes were found in lung, liver and kidney in PQ group under the light microscope, which were significantly more severe than those in HPQ group. The pathologic scores of lung tissue, liver and renal tubular damage on the 1st, 3rd, 7th days after exposure in HPQ group were significantly lower than those in PQ group (P < 0.05). CONCLUSION: When acute PQ poising, rabbits appeared the quick absorption, high toxicity and long half-life time of PQ. The early hemoperfusion can effectively remove the toxicant in plasma and reduce the pathological injury in major organs, which may be beneficial for further treatment.

[Intervention effect of dimercaptopropansulfonate sodium on central toxic induced by bromoxynil in vivo].

OBJECTIVE: to investigate the changes of γ-aminobutyric acid (GABA) and glutamate (Glu) in the cerebral cortex following acute bromoxynil intoxication in mice and the protective effect of sodium dimercaptopropane sulfonate (Na-DMPS). METHODS: 30 ICR mice were randomly divided into blank control group (10), exposure group (10) and Na-DMPS protection group (10). The levels of GABA and Glu in the cerebral cortex were measured by RP-HPLC. The glutamine (Gln) level and the glutamine synthetase (GS), glutamate decarboxylation enzyme (GAD), γ-aminobutyric acid transaminase (GABA-T) activity in the cerebral cortex were determined by UV colorimetric. RESULTS: compared with the control group [GABA: (3.41 ± 0.12) micromol/g, Glu (14.00 ± 0.16) micromol/g, Gln (1.25 ± 0.19) micromol/g, GAD (13.50 ± 0.25) micromol × g(-1) × h(-1), GABA-T (25.51 ± 0.21) micromol × g(-1) × h(-1), GS(142.19 ± 1.31) U/mg pro], the level of GABA [(3.14 ± 0.14) micromol/g] was decreased (P < 0.05), whereas the level of Glu [(17.54 ± 0.40) micromol/g] and Gln [(3.35 ± 0.27) micromol/g] were increased (P < 0.05), the activity of GAD [(11.93 ± 0.15 micromol × g(-1) × h(-1)], GABA-T [(24.15 ± 0.22) micromol × g(-1) × h(-1)], GS [(140.75 ± 1.01) U/mg pro] was decreased (P < 0.05) in acute intoxication group; Compared with the acute intoxication group, the level of GABA [(3.52 ± 0.30) micromol/g] was increased (P < 0.05), whereas the level of Glu [(14.20 ± 0.32) micromol/g] and Gln [(1.32 ± 0.17) micromol/g] were decreased (P < 0.05), the activity of GAD [(13.01 ± 0.45 micromol × g(-1) × h(-1)], GABA-T [(25.19 ± 0.26) micromol × g(-1) × h(-1), GS [(142.35 ± 1.20) U/mg pro] was increased (P < 0.05); In contrast, the levels of GABA, Glu, Gln and the activity of GAD, GABA-T, and GS in Na-DMPS protection group were not significantly different in comparison with control group (P > 0.05). CONCLUSION: the central toxic effects of mice with acute bromoxynil intoxication may be related to the changes of GABA and Glu content in the cerebral cortex;Na-DMPS can protect mice from bromoxynil-induced central toxic effects and GABA and Glu abnormal change in the cerebral cortex.