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Resumo Fundamento A remodelação adversa dos vasos pulmonares eleva a pressão pulmonar e provoca hipertensão arterial pulmonar (HAP). A HAP resulta em aumento da pós-carga do ventrículo direito (VD), causando hipertrofia ventricular e consequente insuficiência cardíaca. Não existe um tratamento específico para o remodelamento desadaptativo do VD secundário à HAP. Objetivos Este estudo tem como objetivo explorar duas abordagens terapêuticas, o suco de uva (SU) e os hormônios tireoidianos (HT), no tratamento do estresse oxidativo induzido pela HAP e nas alterações funcionais cardíacas. Métodos Parâmetros ecocardiográficos relacionados à resistência dos vasos pulmonares (relação TA/TE), contratilidade do VD (ESPAT) e função diastólica do VD (relação dos picos E/A) foram avaliados. Além disso, foram medidos ROS totais, peroxidação lipídica, enzimas antioxidantes, proteínas de manipulação de cálcio, expressão de proteínas pró-oxidantes e antioxidantes. Valores de p<0,05 foram considerados estatisticamente significativos. Resultados Ambos os tratamentos, com SU e HT, demonstraram uma redução na resistência pulmonar (~22%), além de melhorias na ESPAT (inotropismo ~11%) e na relação TA/TE (~26%) (p<0,05). Não houve alterações entre os grupos na relação do pico de E/A. Embora ROS e TBARS não tenham sido estatisticamente significativos, os tratamentos com SU e HT diminuíram os níveis de xantina oxidase (~49%) e normalizaram a expressão de HSP70 e proteínas de manipulação de cálcio (p<0,05). No entanto, apenas o tratamento com HT melhorou a função diastólica (~50%) e aumentou o imunoconteúdo de NRF2 (~48%) (p<0,05). Conclusões Até onde sabemos, este estudo é pioneiro ao mostrar que o HT administrado em conjunto com o SU promoveu melhorias funcionais e bioquímicas em um modelo de HAP. Além disso, nossos dados sugerem que os tratamentos com SU e HT se mostraram cardioprotetores, sejam combinados ou não, e exibiram seus benefícios ao modular o estresse oxidativo e as proteínas de manipulação do cálcio.
Abstract Background Adverse remodeling of lung vessels elevates pulmonary pressure and provokes pulmonary arterial hypertension (PAH). PAH results in increased right ventricle (RV) afterload, causing ventricular hypertrophy and the onset of heart failure. There is no specific treatment for maladaptive RV remodeling secondary to PAH. Objectives This study aims to explore two therapeutic approaches, grape juice (GJ) and thyroid hormones (TH), on PAH-induced oxidative stress and cardiac functional changes. Methods Parameters of echocardiography related to lung vessel resistance (AT/ET ratio), RV contractility (TAPSE), and RV diastolic function (E/A peaks ratio) were evaluated. Also, total ROS, lipid peroxidation, antioxidant enzymes, calcium handling proteins, pro-oxidant and antioxidant protein expression were measured. Values of p<0.05 were considered statistically significant. Results Both GJ and TH treatments demonstrated reductions in pulmonary resistance (~22%) and improvements in TAPSE (inotropism ~11%) and AT/ET ratio (~26%) (p<0.05). There were no changes amongst groups regarding the E/A peak ratio. Although ROS and TBARS were not statistically significant, GJ and TH treatments decreased xanthine oxidase (~49%) levels and normalized HSP70 and calcium handling protein expression (p<0.05). However, only TH treatment ameliorated diastolic function (~50%) and augmented NRF2 immunocontent (~48%) (p<0.05). Conclusions To the best of our knowledge, this study stands as a pioneer in showing that TH administered together with GJ promoted functional and biochemical improvements in a PAH model. Moreover, our data suggest that GJ and TH treatments were cardioprotective, combined or not, and exhibited their beneficial effects by modulating oxidative stress and calcium-handling proteins.
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Objective To investigate the effect of BMAL1 on H2O2-induced cardiomyocyte injury through NRF2-regulated ROS/NLRP3 inflammasome pathway.Methods H9c2 cells and H9c2 cells with stable over-expressed BMAL1 were cultured and divided into the control group,the H2O2 group,the BMAL1-OE group,the BMAL1-OE+H2O2 group,the BMAL1-OE+ML385 group and the BMAL1-OE+ML385+H2O2 group.All groups were pre-intervened with corresponding inhibitors,and then treated with 0.2 mmol/L H2O2,except for the control group and the BMAL1-OE group.After the intervention,CCK-8 assay was used to measure cell viability,fluorescent probe DCFH-DA was used to measure ROS generation and Western blot assay was used to detect BMAL1,NRF2 and NLRP3 protein expressions.ELISA was used to determine IL-1β release.Results Compared with the control group,the cell viability was decreased,ROS generation was increased,BMAL1 and NRF2 protein expressions were decreased,NLRP3 expression and IL-1β release were increased in the H2O2 group(P＜0.05).Compared with the H2O2 group,the cell viability was increased,ROS generation was decreased,BMAL1-OE and NRF2 protein expressions were increased,NLRP3 expression and IL-1β release were decreased in the BMAL1-OE+H2O2 group(P＜0.05).Compared with the BMAL1-OE+H2O2 group,the cell viability was decreased,ROS generation was increased,NLRP3 expression and IL-1β release were increased in the BMAL1-OE+ML385+H2O2 group(P＜0.05).Conclusion BMAL1 attenuates H2O2-induced H9c2 cardiomyocyte injury,and its mechanism may be related to the regulation of ROS/NLRP3 inflammasome pathway through NRF2.
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Objective To explore the mechanism of Wumei pill on ulcerative colitis(UC)in mice based on the anti oxidative stress pathway of nuclear factor erythroid 2-related factor 2(Nrf2)/antioxidant response element(ARE).Methods Seventy SPF male C57BL/6 mice were randomly divided into the control group,the UC group,the mesalazine group(MES group,0.82 g/kg MES),the low dose Wumei pill group(WMW-L group,5 g/kg crude drug),the middle dose Wumei pill group(WMW-M group,10 g/kg crude drug),the high dose Wumei pill group(WMW-H group,20 g/kg crude drug)and the high dose Wumei pills+Nrf2 inhibitor ML-385 group(WMW-H+ML-385 group,Wumei pills crude drug 20 g/kg+20 mg/kg ML-385),with 10 rats in each group.The disease activity index(DAI)score and colonic mucosa injury score were performed in mice after the last administration.Pathological changes of colonic mucosa in mice were observed by HE staining.The levels of interleukin(IL)-1β,tumor necrosis factor-α(TNF-α)and IL-6 in serum and colon tissue of mice were measured by enzyme-linked immunosorbent assay(ELISA).The content of malondialdehyde(MDA)in serum and colon tissue of mice was determined by thiobarbituric acid colorimetry(TBA).The activity of superoxide dismutase(SOD)in serum and colon tissue of mice was measured by xanthine oxidase method.The activity of glutathione peroxidase(GSH-px)in serum and colon tissue of mice was determined by direct method with dithiodinitrobenzoic acid(DTNB).The positive expression of Nrf2 in colon tissue of mice was observed by immunohistochemistry.The expression of heme oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase-1(NQO1)proteins in colon tissue of mice were detected by Western blot assay.Results Compared with the control group,the DAI score,colonic mucosa injury score,colonic histopathology score,levels of IL-1β,TNF-α,IL-6 and MDA in serum and colonic tissue,and expression levels of Nrf2,HO-1 and NQO1 protein in colonic tissue of mice were increased in the UC group,levels of SOD and GSH-px in serum and colon tissue decreased(P＜0.05),the colon mucosa of mice was seriously damaged.Compared with the UC group,changes of corresponding indexes were contrary to the above in the MES group,the WMW-M group and the WMW-H group.However,the expression levels of Nrf2,HO-1 and NQO1 proteins in colon tissue were increased(P＜0.05),and the damage of colon mucosa in mice was alleviated.Changes of the above indexes were dose-dependent in the WMW-L group,the WMW-M group and the WMW-H group.There were no significant differences in the above indexes between the WMW-H group and the MES group.ML-385 attenuated the improvement effect of high dose Wumei pill on colon mucosa injury.Conclusion Wumei pill may alleviate the colon mucosal damage of UC mice by activating Nrf2/ARE antioxidant stress pathway.
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Objective:To evaluate the role of reactive oxygen species (ROS) in attenuation of hypoxia-reoxygenation (H/R) injury in rat cardiomyocytes by pinacidil postconditioning and the relationship with nuclear factor erythrid 2-related factor 2 (Nrf2)-antioxidant response element (ARE) signaling pathway.Methods:Adult rat cardiomyocytes were isolated and cultured and then divided into 4 groups ( n=20 each) by a random number table method: control group (group C), H/R group, pinacidil postconditioning group (group P) and reactive oxygen scavenger N-(2-mercaptopropionyl)-glycine(MPG)+ pinacidil postconditioning group (group MPG+ P). Group C was continuously exposed to 95%O 2+ 5%CO 2 in an incubator at 37 ℃ for 105 min. The cells were exposed to 5%CO 2+ 1%O 2+ 94%N 2 in an incubator at 37 ℃ for 45 min followed by reoxygenation for 60 min to prepare H/R injury model. The cells were exposed to hypoxia for 45 min and then treated with pinacidil 50 μmol/L for 5 min followed by reoxygenation for 60 min in group P. The cells were exposed to hypoxia for 45 min, treated with MPG 2 mmol/L for 10 min, and then treated with pinacidil for 5 min followed by reoxygenation for 60 min in group MPG+ P. The content of Ca 2+ and activity of Nrf2 in cardiomyocytes were measured at the end of reoxygenation. The ultrastructure of cardiomyocytes was observed, and mitochondrial ultrastructure was evaluated using mitochondrial Flameng score. The expression of Nrf2, superoxide dismutase (SOD1), quinone oxidoreductase 1 (NQO1), and heme oxygenase 1 (HO-1) protein and mRNA was detected using Western blot and real-time polymerase chain reaction. Results:Compared with group C, the Ca 2+ content, Nrf2 activity and mitochondrial Flameng score were significantly increased, the expression of Nrf2, SOD1, NQO1 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the damage to the ultrastructure of cardiomyocytes was aggravated in group H/R. Compared with H/R group, the Ca 2+ content and mitochondrial Flameng score were significantly decreased, the Nrf2 activity was increased, the expression of Nrf2, SOD1, NQO1 and HO-1 protein and mRNA was up-regulated ( P<0.05), and the damage to the ultrastructure of cardiomyocytes was attenuated in P group. Compared with P group, the Ca 2+ content and mitochondrial Flameng score were significantly increased, the Nrf2 activity was decreased, the expression of Nrf2, SOD1, NQO1 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the damage to the ultrastructure of cardiomyocytes was aggravated in MPG+ P group. Conclusions:ROS is involved in attenuation of H/R injury by pinacidil postconditioning, which is associated with activation of the Nrf2-ARE signaling pathway in rat cardiomyocytes.
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Objective:To evaluate the role of nuclear factor E2-related factor 2 (Nrf2)/heme oxidase-1 (HO-1) in reduction of renal ischemia-reperfusion (I/R) injury by the human umbilical cord mesenchymal stem cells (hucMSCs)-derived exosomes (hucMSCs-exo) in mice.Methods:The hucMSCs were cultured, and exosomes were extracted and identified by transmission electron microscopy, nanoparticle tracking analysis and Western blot. Thirty-six male SPF-grade C57BL/6 mice, weighing 20-25 g, were used. Thirty mice were selected and divided into 5 groups ( n=6 each) by a random number table method: sham operation group (Sham group), sham operation + Nrf2 inhibitor ML385 group (Sham + ML385 group), renal I/R group (I/R group), renal I/R + exosome group (I/R+ EXO group), and renal I/R + exosome + Nrf2 inhibitor ML385 group (I/R+ EXO+ ML385 group). A model of renal I/R injury was prepared by clamping the bilateral renal pedicles for 45 min followed by perfusion in anesthetized animals. ML385 30 mg/kg was intraperitoneally injected at 45 min before preparing the model in Sham+ ML385 group and I/R+ EXO+ ML385 group, and hucMSCs-exo 100 μg was injected via the tail vein at 15 min before reperfusion in I/R+ EXO group and I/R+ EXO+ ML385 group. Serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations were detected at 24 h of reperfusion. The renal tissues were obtained for examination of the pathological changes and for determination of contents of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and malondialdehyde (MDA), superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels and expression of Nrf2 and HO-1 protein and mRNA (by Western blot and quantitative real-time polymerase chain reaction). The left 6 mice were allocated to sham operation group (Sham-IM group, n=3) and renal I/R group (I/R-IM group, n=3) by a random number table method for VISQUE in living imaging observation. Results:The exosomes showed a typical cup-shaped morphology with a transmission electron microscope, the nanoparticles tracked and analyzed the average diameter of the exosome, with an average diameter of 96.7 nm, and the positive expression of surface markers CD9, CD63 and TSG101 was detected using Western blot. The renal fluorescence intensity value was significantly increased in I/R-IM group as compared with Sham-IM group ( P<0.05). Compared with Sham group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R group, and no significant change was found in serum BUN and Cr concentrations in Sham+ ML385 group ( P>0.05). Compared with I/R group, the serum BUN and Cr concentrations were significantly decreased, the contents of IL-6, TNF-α and MDA and ROS levels were decreased, the activity of SOD was increased, the expression of Nrf2 and HO-1 protein and mRNA was up-regulated ( P<0.05), and the pathological changes of renal tissues were significantly attenuated in I/R+ EXO group. Compared with I/R+ EXO group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R+ EXO+ ML385 group. Conclusions:The mechanism by which hucMSCs-exo reduces renal I/R injury may be related to activation of the Nrf2/HO-1 signaling pathway in mice.
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ABSTRACT After the discovery of anti-vascular endothelial growth factor agents as treatment of wet age-related macular degeneration, the number of studies with the objective to understand the molecular mechanisms involved in the age-re lated macular degeneration genesis has increased. The importance of the nuclear factor e2-related factor 2 lies in its activation-derived proteins being involved in the maintenance of the redox balance and consequent prevention of degenerative macular disease. This article aims to present the characteristics of nuclear factor e2-related factor 2 and describe the main nuclear factor e2-related factor 2-activated antioxidant enzymes that contribute to the preservation of vision.
RESUMO Após a descoberta do anti fator de crescimento en dotelial vascular no tratamento da degeneração macular relacionada à idade úmida, muitas pesquisas têm sido realizadas com o intuito de elucidar os mecanismos moleculares envolvidos na gênese da degeneração macular relacionada à idade. O fator nuclear eritroide 2 relacionado ao fator 2 destaca-se pelo fato de diversas proteínas, oriundas de sua ativação, estarem envolvidas na manutenção do equilíbrio do estado redox e consequente prevenção da doença macular degenerativa. Este artigo mostra as características do fator nuclear eritroide 2 relacionado ao fator 2 e descreve as principais enzimas antioxidantes originadas da ativação que contribuem para a preservação da visão.
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The incidence rate of alcoholic liver disease (ALD) is increasing year by year China, and there is a gradual increase in disease burden among Chinese people. Oxidative stress response in hepatocytes is an important pathogenic mechanism of ALD. The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway is an important endogenous anti-oxidative stress pathway in the body, and Nrf2 is activated in response to oxidative stress and exerts its transcriptional activity to induce high HO-1 expression. HO-1 is an important oxidative stress response protein and plays a role in anti-inflammation, anti- oxidation, and cell apoptosis regulation together with heme hydrolysis products (bilirubin, carbon monoxide, and iron). This article reviews the research advances in the role of the Nrf2/HO-1 signaling pathway in ALD in recent years, so as to find a theoretical basis for the development and progression of ALD and an entry point for treatment.
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Objective To investigate the therapeutic effect of Dange Jiecheng decoction on a rat model of alcoholic liver disease (ALD) and the anti-oxidative stress mechanism of Dange Jiecheng decoction. Methods A total of 96 Sprague-Dawley rats were randomly divided into blank group with 13 rats and ALD group with 83 rats, and the rats in the ALD group were given liquor by gavage to establish a model of ALD. Then the ALD group was randomly divided into model group, high-dose Dange Jiecheng decoction group (24 g/kg), low-dose Dange Jiecheng decoction group (6 g/kg), and Yiganling tablet group (21 mg/kg), with 17 rats in each group. The rats in the blank group and the model group were given normal saline by gavage, and those in the other groups were given corresponding drugs by gavage, for 4 consecutive weeks. HE staining was used to observe the pathological changes of liver tissue; Western blot was used to measure the contents of Kelch-like ECH-associated protein 1 (Keap1), nuclear factor erythroid 2-related factor 2 (Nrf2), and heme oxygenase-1 (HO-1) in liver tissue; quantitative real-time PCR was used to measure the mRNA expression levels of Keap1 and HO-1 in liver tissue. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups. Results Compared with the blank group, the model group had disordered arrangement of hepatocytes with necrosis, massive inflammatory cell infiltration, and a large number of lipid droplet vacuoles, significant increases in the protein and mRNA expression levels of Keap1 ( P < 0.05), and significant reductions in the protein expression levels of Nrf2 and HO-1 and the mRNA expression level of HO-1 ( P < 0.05). Compared with the model group, the high- and low-dose Dange Jiecheng decoction groups and the Yiganling tablet group had ordered arrangement of hepatocytes, reductions in hepatocyte necrosis and inflammatory cells, and occasional lipid droplet vacuoles, as well as significant reductions in the protein and mRNA expression levels of Keap1 ( P < 0.05) and significant increases in the protein expression levels of Nrf2 and HO-1 and the mRNA expression level of HO-1 ( P < 0.05). Conclusion By regulating the Keap1/Nrf2 signaling pathway, Dange Jiecheng decoction can promote the nuclear import of Nrf2, upregulate the expression of HO-1, and alleviate oxidative stress response, thereby exerting a protective effect on ALD rats.
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Nuclear factor-erythroid 2-related factor 2 (Nrf2) is an important transcription factor that regulates redox, lipid metabolism and protein dynamic balance, and plays an important role in protecting the body from oxidative stress damage. Recently, more and more studies have shown that Nrf2 is activated in ovarian cancer by various mechanisms to induce increased antioxidant enzymes, change sex hormone metabolism and induce downstream targets. Further studying the mechanism of Nrf2 in promoting the development of ovarian cancer, exploring its role in drug resistance and seeking new therapeutic targets can provide new ideas for the treatment of drug-resistant ovarian cancer.
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Objective:To investigate the role of miR-144-3p in cisplatin resistance of bladder cancer.Methods:Bladder cancer T24 cells were cultured in vitro and divided into blank group (untreated), mimetic control group, miR-144-3p mimetic transfection group, inhibitor control group, and miR-144-3p inhibitor transfection group. Real time fluorescence quantitative polymerase chain reaction (qRT-PCR) was used to verify the transfection effect, methyl thiazolyl tetrazolium (MTT) method was used to detect the survival rate of cells treated with cisplatin in each group, and Western blot was used to detect the expression of the target protein. The targeting relationship between miR-144-3p and nuclear factor E2 related factor 2 (Nrf2) was validated using dual fluorescence reporter gene experiments. Furthermore, Nrf2 was knocked out in each group of cells, and the mRNA and protein expression levels of HO-1, Bcl-2, and Caspase-3 were detected by qRT-PCR and Western blot in each group of cells.Results:Compared with the control group, bladder cancer cells in the miR-144-3p mimetic transfection group were more sensitive to cisplatin, while the miR-144-3p inhibitor transfection group had the opposite effect; The miR-144-3p simulant transfection group can effectively inhibit the mRNA and protein expression level of Nrf2 in bladder cancer cells (all P<0.05), while the miR-144-3p inhibitor transfection group can up regulate the mRNA and protein level of Nrf2 (all P<0.05). The miR-144-3p mimetic transfection group showed significant downregulation of mRNA and protein expression of HO-1 and Bcl-2, while the expression of Caspase-3 was upregulated (all P<0.05), while the miR-144-3p inhibitor transfection group showed the opposite results. The luciferase results confirmed that miR 144 3p can directly bind to the 3′- UTR region of Nrf2, reducing the mRNA level of Nrf2. When Nrf2 was knocked out, whether miR-144-3p mimetic transfection group or miR-144-3p inhibitor transfection group, the mRNA and protein expression levels of HO-1, Bcl-2 and Caspase-3 did not change significantly, and miR-144-3p lost the ability to regulate the cisplatin sensitivity of bladder cancer cells. Conclusions:miR-144-3p targets to regulate the sensitivity of Nrf2 to cisplatin in bladder cancer, and miR-144-3p is expected to become a new target for the treatment of cisplatin resistant or refractory bladder cancer.
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Objective:To evaluate the role of nuclear factor erythroid 2-related factor 2 (Nrf2)/nucleotide-binding oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3) signaling pathway in propofol postconditioning-induced reduction of hippocampal neuron injury in a rat model of oxygen-glucose deprivation and restoration (OGD/R).Methods:The hippocampal neurons were isolated from fetal rats of Wistar rats at 16-18 days of gestation and primarily cultured for 7 days and then divided into 4 groups ( n=42 each) using a random number table method: control group (group C), OGD/R group (group O), propofol post-conditioning group (group P) and Nrf2 siRNA(-) transfection group (group N). The cells were routinely cultured in group C. The cells were subjected to oxygen-glucose deprivation for 1 h followed by oxygen and glucose supply in group O. Propofol (final concentration 1.2 μg/ml) was added immediately after oxygen and glucose supply, the cells were then cultured for 2 h, and the culture medium was replaced with the normal culture medium in group P. The primarily cultured neurons were transfected with Nrf2 gene knockout lentivirus on 3rd day of culture, 24 h later the cells were then routinely cultured, and the model was prepared and propofol conditioning was performed on 7th day. Cells were collected at 24 h of incubation for determination of the cell apoptosis (by flow cytometry), expression of Nrf2 and NLRP3 mRNA and protein (using quantitative real-time polymerase chain reaction or Western blot), concentrations of tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and IL-1β, and activities of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT) (kit method). Results:Compared with group C, the apoptosis rate of neurons was significantly increased, concentrations of TNF-α, IL-6 and IL-1β were increased, the levels of GSH, SOD and CAT were decreased, the expression of Nrf2 and NLRP3 protein and mRNA was up-regulated, and the nuclear/plasma ratio of Nrf2 was increased in O and P groups ( P<0.05). Compared with group O, the apoptosis rate of neurons was significantly decreased, the concentrations of TNF-α, IL-6 and IL-1 β were decreased, the levels of GSH, SOD and CAT were increased, the expression of Nrf2 protein and mRNA was up-regulated, the nuclear/plasma ratio of Nrf2 was increased, and the expression of NLRP3 protein and mRNA was down-regulated in group P ( P<0.05). Compared with group P, the apoptosis rate of neurons was significantly increased, concentrations of TNF-α, IL-6 and IL-1β were increased, the levels of GSH, SOD and CAT were decreased, the expression of Nrf2 protein and mRNA was down-regulated, the nuclear/plasma ratio of Nrf2 was decreased, and the expression of NLRP3 protein and mRNA was up-regulated in group N ( P<0.05). Conclusions:Nrf2/NLRP3 signaling pathway is involved in propofol postconditioning-induced reduction of hippocampal neuron injury in a rat model of OGD/R.
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Objective:To evaluate the role of NF-E2-related factor 2 (Nrf2)/heme oxygenase (HO-1) signaling pathway in reduction of endotoxin-induced acute lung injury (ALI) by esketamine and the relationship with NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome-mediated pyroptosis in mice.Methods:SPF male wild-type (WT) and Nrf2 knockout (KO) C57BL/6J mice, aged 6-8 weeks, weighing 20-25 g, were divided into 3 groups ( n=6 each) using a random number table method: control group (WT+ C group, KO+ C group), ALI group (WT+ ALI group, KO+ ALI group) and ALI+ esketamine group (WT+ ALI+ E group, KO+ ALI+ E group). ALI model was developed by injection of lipopolysaccharide (LPS) 15 mg/kg via the tail vein. Esketamine 10 mg/kg was intraperitoneally injected at 30 min after LPS injection, and 6 h later the medication was repeated for one time in WT+ ALI+ E and KO+ ALI+ E groups, while the equal volume of normal saline was given in the other groups. The mice were anesthetized at 12 h after LPS injection, and blood samples were obtained by cardiac puncture for determination of serum interleukin-1beta (IL-1β) and IL-18 concentrations, and bilateral lung tissues were also obtained for examination of the pathological changes of lung tissues(with the light microscope) which were scored and for determination of the content of reduced glutathione (GSH) and expression of Nrf2, HO-1 and NLRP3 inflammasome-mediated pyroptosis-related proteins (NLRP3, apoptosis-associated speck-like protein containing a CARD[ASC], pro-caspase-1, cleaved-caspase-1, gasdermin D[GSDMD]) (by Western blot). Results:Compared with the corresponding C group (WT+ C group or KO+ C group), the lung injury score and concentrations of IL-1β and IL-18 were significantly increased, the content of GSH in lung tissues was decreased, and the expression of NLRP3, ASC, pro-caspase-1, cleved-caspase-1 and GSDMD was up-regulated in WT+ ALI group and KO+ ALI group ( P<0.05), and the expression of Nrf2 and HO-1 was significantly up-regulated in WT+ ALI group( P<0.05). Compared with the corresponding ALI group (WT+ ALI group or KO+ ALI group), the lung injury score and concentrations of IL-1β and IL-18 were significantly decreased, the content of GSH in lung tissues was increased, and the expression of NLRP3, ASC, pro-caspase-1, cleved-caspase-1 and GSDMD was down-regulated in WT+ ALI+ E group and KO+ ALI+ E group ( P<0.05), and Nrf2 and HO-1 expression was significantly up-regulated in WT+ ALI+ E group( P<0.05). Compared with WT+ ALI+ E group, the lung injury score and concentrations of IL-1β and IL-18 were significantly increased, the content of GSH in lung tissues was decreased, the expression of Nrf2 and HO-1 was down-regulated, and the expression of NLRP3, ASC, pro-caspase-1, cleved-caspase-1 and GSDMD was up-regulated in KO+ ALI+ E group ( P<0.05). Conclusions:The mechanism by which esketamine reduces endotoxin-induced ALI may be related to activation of Nrf2/HO-1 signaling pathway, thus inhibiting NLRP3 inflammasome-mediated pyroptosis in mice.
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Objective:To evaluate the effect of panaxydol on ventilator-induced lung injury(VILI) in mice, and the relationship with Kelch-like ECH-associated protein 1 (Keap1)/nuclear factor E2-related factor 2 (Nrf2) signaling pathway.Methods:Fifty healthy clean-grade male C57BL/6 mice, aged 6-8 weeks, weighing 20-25 g, were divided into 5 groups ( n=10 each) using a random number table method: control group (group C), VILI group, low-dose panaxydol group (L-PX group, 5 mg/kg), medium-dose panaxydol group (M-PX group, 10 mg/kg) and high-dose panaxydol group (H-PX group, 20 mg/kg). The corresponding doses of panaxydol were intraperitoneally injected for 7 consecutive days once a day in L-PX group, M-PX group and H-PX group. The equal volume of normal saline was given instead in C group and VILI group. Only tracheotomy was performed and animals kept spontaneous breathing for 4 h in group C, and the animals were mechanically ventilated (tidal volume 30 ml/kg, respiratory rate 70 breaths/min, inspiratory/expiratory ratio 1∶2, fraction of inspired oxygen 21%) for 4 h in VILI, L-PX, M-PX and H-PX groups. Blood samples from the femoral artery were collected for arterial blood gas analysis at 4 h of ventilation, and PaO 2 was recorded. The mice were then sacrificed under deep anesthesia, and bronchoalveolar lavage fluid (BALF), lung tissues and serum samples were collected. The concentrations of TNF-α and IL-1β in BALF and serum were measured by enzyme-linked immunosorbent assay. The wet/dry lung weight (W/D) ratio was measured, the protein concentrations in BALF were measured by bicinchoninic acid assay, the pathological changes of lung tissues were examined by HE staining, lung injury was scored, and the level of ROS in lung tissues was detected by DCFH-DA fluorescence probe.The expression of Keap1 and Nrf2 in lung tissues was detected by Western blot. Results:Compared with group C, the PaO 2 was significantly decreased, the lung injury score, W/D ratio, protein concentrations in BALF and concentrations of TNF-α and IL-1β in BALF and serum were increased, the expression of Keap1 and Nrf2 was up-regulated, and the fluorescence of ROS was enhanced in the other four groups ( P<0.05). Compared with group VILI, PaO 2 was significantly increased, the lung injury score was decreased, lung W/D ratio, protein concentrations in BALF, and concentrations of TNF-α and IL-1 β in BALF and serum were decreased, and the fluorescence of ROS was weakened in L-PX, M-PX, and H-PX groups, and the expression of Keap1 was down-regulated, the fluorescence of ROS was weakened, and the expression of Nrf2 was up-regulated in M-PX and H-PX groups ( P<0.05). Compared with group L-PX, PaO 2 was significantly increased, the lung injury score, W/D ratio, protein concentrations in BALF and concentrations of TNF-α and IL-1β in BALF were decreased, the expression of Keap1 was down-regulated, and the expression of Nrf2 was up-regulated and the fluorescence of ROS was weakened in M-PX and H-PX groups ( P<0.05). Compared with group M-PX, PaO 2 was significantly increased, the lung injury score, W/D ratio, protein concentrations in BALF and concentrations of TNF-α and IL-1β in BALF were decreased, the expression of Keap1 was down-regulated, the expression of Nrf2 was up-regulated, and the fluorescence of ROS was weakened in H-PX group( P<0.05). Conclusions:Panaxydol can reduce VILI in mice, and the mechanism may be related to activation of the Keap1/Nrf2 signaling pathway and inhibition of oxidative stress.
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Objective:To evaluate the role of silencing information regulatory factor 1/nuclear factor E2 related factor 2 (SIRT1/Nrf2) signaling pathway in berberine preconditioning-induced reduction of intestinal ischemia-reperfusion (I/R) injury in mice and the relationship with ferroptosis.Methods:Thirty-six SPF-grade healthy male C57BL/6 mice, aged 8-10 weeks, weighing 22-25 g, were divided into 6 groups ( n=6 each) by a random number table method: sham operation group (S group), sham operation + berberine preconditioning group (SB group), intestinal I/R group (IR group), intestinal I/R + berberine preconditioning group (B group), intestinal I/R + berberine preconditioning + SIRT1 inhibitor EX527 group (BE group) and berberine preconditioning + intestinal I/R + ferroptosis inducer RSL3 group (BR group). The model of intestinal I/R injury was prepared by clamping the superior mesenteric artery for 45 min followed by 30-min reperfusion in IR group, B group, BE group and BR group, while the superior mesenteric artery was only isolated without ligation in S group and SB group. Berberine 50 mg/kg was administered by intragastric gavage once a day starting from 7 days before developing the model in SB group, B group, BE group and BR group. EX527 5 mg/kg and RSL3 5 mg/kg were intraperitoneally injected once a day at 3 days before surgery in BE group and BR group, respectively. The equal volume of normal saline was given in the other groups. The mice were sacrificed at 30 min of reperfusion, and the intestinal tissues were taken for microscopic examination of the pathological changes of intestinal mucosa (with a light microscope) which was scored according to Chiu and for determination of the contents of Fe 2+ and malondialdehyde (MDA) and superoxide dismutase (SOD) activity (by colorimetry), glutathione (GSH) content (by enzyme-linked immunosorbent assay), reactive oxygen species (ROS) content (by fluorescence staining), and expression of glutathione peroxidase 4 (GPX4), SIRT1 and Nrf2 (by Western blot). Results:Compared with S group, Chiu′s score was significantly increased, the contents of Fe 2+, MDA and ROS were increased, the content of GSH and activity of SOD were decreased, the expression of GPX4 was down-regulated, and the expression of SIRT1 and Nrf2 was up-regulated in IR group ( P<0.05), and no significant change was found in Chiu′s score in SB group ( P>0.05). Compared with IR group, Chiu′s score was significantly decreased, the contents of Fe 2+, MDA and ROS were decreased, the content of GSH and activity of SOD were increased, the expression of GPX4 was up-regulated, and the expression of SIRT1 and Nrf2 was up-regulated in B group ( P<0.05). Compared with B group, Chiu′s score was significantly increased, the contents of Fe 2+, MDA and ROS were increased, the content of GSH and activity of SOD were decreased, and the expression of GPX4 was down-regulated in BE and BR groups, and the expression of SIRT1 and Nrf2 was down-regulated in BE group( P<0.05). Conclusions:The mechanism by which berberine preconditioning reduces intestinal I/R injury may be associated with activation of SIRT1/Nrf2 signaling pathway, thus inhibiting ferroptosis in mice.
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Objective:To evaluate the role of nuclear factor-erythroid 2-related factor 2 (Nrf2)/glutathione peroxidase-4 (GPX4) signaling pathway-mediated ferroptosis in midazolam-induced reduction of hypoxic-ischemic brain damage (HIBD) in neonatal rats.Methods:Ninety healthy 7-day-old neonatal rats, weighing 16-20 g, were divided into 6 groups ( n=15 each) using the random number table method: sham operation group (Sham group), HIBD group, low-dose midazolam (10 mg/kg) group (group L), medium-dose midazolam (20 mg/kg) group (group M), high-dose midazolam (40 mg/kg) group (group H), and Nrf2 inhibitor ML385 group (group I). The HIBD model was developed by ligating the left carotid artery and exposing to a hypoxic condition for 2 h in anesthetized animals. Starting from 2nd day after developing the model, the corresponding doses of midazolam were intraperitoneally injected in midazolam groups, the equal volume of normal saline was intraperitoneally injected in Sham and HIBD groups, midazolam 40 mg/kg and Nrf2 inhibitor ML385 30 mg/kg were intraperitoneally injected once a day for 8 consecutive days in group I. The rats were weighed and subjected to the Morris water maze test after the end of administration. Blood samples were taken from the abdominal aorta after the end of the Morris water maze test, and then the animals were sacrificed to remove the brain for determination of the concentrations of serum iron, interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) (by enzyme-linked immunosorbent assay), contents of iron and GSH in hippocampal tissues (by ultraviolet spectrophotometry and micro method), the number of Nrf2/neuronal nuclear antigen (NeuN) and GPX4/NeuN positive cells (by immunofluorescent staining), and expression of Nrf2, GPX4, and 4-hydroxynonaenoic acid (4-HNE) in hippocampal tissues and for microscopic examination of the pathological changes of hippocampal neurons in brain tissues (after HE staining and Nissl staining). Results:Compared with Sham group, the first time to arrival at platform was significantly prolonged, the number of crossing the origional platform was reduced, and the time of staying at the target quadrant was shortened, the iron content in the hippocampal tissues was increased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were decreased, the expression of Nrf2 and GPX4 was down-regulated, the expression of 4-HNE was up-regulated, the concentrations of serum iron, IL-6 and TNF-α were increased, and the injury to hippocampal neurons was marked in HIBD group ( P<0.05). Compared with HIBD group, the first time to arrival at platform was significantly shortened, the number of crossing the origional platform was increased, and the time of staying at the target quadrant was prolonged, the iron content in the hippocampus tissues was decreased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were increased, the expression of Nrf2 and GPX4 was up-regulated, the expression of 4-HNE was down-regulated, the concentrations of serum iron, IL-6 and TNF-α were decreased ( P<0.05), and the injury to hippocampal neurons was significantly reduced in H, M and L groups. Compared with group H, the first time to arrival at platform was significantly prolonged, the number of crossing the origional platform was reduced, and the time of staying at the target quadrant was shortened, the iron content in the hippocampus tissue was increased, the content of GSH and the number of Nrf2/NeuN and GPX4/NeuN positive cells were decreased, the expression of Nrf2 and GPX4 was down-regulated, the expression of 4-HNE was up-regulated, the concentrations of serum iron, IL-6 and TNF-α were increased ( P<0.05), and the injury to hippocampal neurons was aggravated in group I. Conclusions:The mechanism by which midazolam reduces HIBD may be related to activation of the Nrf2/GPX4 signaling pathway and inhibition of hippocampal neuronal ferroptosis in neonatal rats.
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Objective:To evaluate the role of nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway in edaravone-induced attenuation of long-term cognitive impairment caused by long-time sedation with propofol in the neonatal rats.Methods:Eighty SPF healthy newborn Sprague-Dawley rats of both sexes, aged 7 days, weighing 15-20 g, were divided into 4 groups ( n=20 each) using a random number table method: control group (group C), propofol group (group P), edaravone+ propofol group (group EP) and Nrf2 inhibitor ML385+ edaravone+ propofol group (group MEP). Propofol 75 mg/kg was intraperitoneally injected once a day for 7 consecutive days in P group, EP group and MEP group, respectively, while the equal volume of medium/long chain fat emulsion injection was intraperitoneally injected in C group. Edaravone 3 mg/kg was intraperitoneally injected at 30 min before each propofol injection in EP and MEP groups, and ML385 15 mg/kg was intraperitoneally injected simultaneously in group MEP. The spontaneous activity was evaluated by the open field test on day 29 after birth, and the cognitive function was assessed by Morris water maze test on days 30-34 after birth. The rats were sacrificed after the end of water maze test, and brains were removed and hippocampal tissues were obtained for determination of reactive oxygen species (ROS) levels (by flow cytometry), superoxide dismutase (SOD) and malondialdehyde (MDA) levels (by enzyme-linked immunosorbent assay) and expression of Nrf2 and HO-1 (by Western blot) and for microscopic examination of the pathological changes in the hippocampal CA1 area (using HE staining). Results:There was no significant difference in the speed, distance and time of stay at the center of the open field among the four groups ( P>0.05). Compared with C group, the escape latency was significantly prolonged, the number of crossing the original platform quadrant was reduced, the levels of MDA and ROS were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 was down-regulated ( P<0.05), and the pathological injury was observed in the hippocampal CA1 region in group P. Compared with P group, the escape latency was significantly shortened, the number of crossing the original platform quadrant was increased, the levels of MDA and ROS in the hippocampus were decreased, the activity of SOD was increased, the expression of Nrf2 and HO-1 was up-regulated ( P<0.05), and the pathological injury in the hippocampal CA1 region was significantly alleviated in EP group. Compared with EP group, the escape latency was significantly prolonged, the number of crossing the original platform quadrant was reduced, the levels of MDA and ROS were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 was down-regulated ( P<0.05), and the pathological injury was aggravated in the hippocampal CA1 region in MEP group. Conclusions:The mechanism by which edaravone attenuates long-term cognitive impairment caused by long-time sedation with propofol is related to activation of Nrf2/HO-1 signaling pathway and inhibition of oxidative stress in the neonatal rats.
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ObjectiveTo investigate the protective effect of safranal against sepsis-related liver injury （SRLI） induced by lipopolysaccharide （LPS） in mice and its mechanism. MethodsA total of 32 experimental male C57BL/6 mice were divided into control group， single drug group， model group， and treatment group using the simple random method， with 8 mice in each group. The mice in the single drug group and the treatment group were intraperitoneally injected with safranal （60 mg/kg） for 7 days of pretreatment， and the mice in the model group and the treatment group were intraperitoneally injected with LPS （10 mg/kg） to induce acute liver injury. The activities of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were measured； HE staining was used to observe liver tissue sections； immunohistochemistry was used to analyze the expression of the downstream protein heme oxygenase-1 （HO-1） in the signal pathway； TUNEL was used to analyze the apoptosis of hepatocytes； Western blot was used to measure the expression of total proteins （nuclear factor erythroid 2-related factor 2 ［Nrf-2］ and HO-1） in liver tissue. The human liver cell line L02 was pretreated with safranal （100 μmol/L）， followed by induction of acute hepatocellular injury with LPS （100 ng/mL）， and DCFH-DA fluorescent labeling was used to detect reactive oxygen species （ROS）. ResultsAfter safranal pretreatment， the treatment group had significantly lower levels of ALT and AST than the model group （both P<0.001）， with a relatively intact pseudolobular structure and a smaller necrotic area in the liver. Compared with the model group， the treatment group had significant increases in the expression levels of Nrf2 and HO-1 in liver tissue after safranal+LPS treatment （both P<0.001）， and immunohistochemistry showed that safranal pretreatment increased the number of HO-1-positive cells. In the cell model of LPS-induced acute liver injury， the treatment group had a significant reduction in the production of ROS compared with the model group. ConclusionSafranal can exert a protective effect against SRLI induced by LPS in mice through the Nrf2/HO-1 pathway.
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Objective:To evaluate the relationship between nuclear factor E2-related factor 2 (Nrf2) and ferroptosis during lung ischemia-reperfusion (I/R) in rats.Methods:Fifty-four healthy male Sprague-Dawley rats, weighing 220-250 g, were divided into 3 groups ( n=18 each) using a random number table method: sham operation group (Sham group), lung I/R group (IR group), and lung I/R+ Nrf2 agonist sulforaphane group (IR+ SFP group). Lung I/R model was developed by clamping the left pulmonary hilum for 60 min followed by 120 min of reperfusion.In IR+ SFP group, SFP 500 μg/kg was intraperitoneally injected at 3 days before lung ischemia once a day for 3 consecutive days, and the model was developed at 2 h after the end of administration.The rats were sacrificed at the end of reperfusion, and the bronchoalveolar lavage fluid (BALF) was collected to determine the protein concentration (using bicinchoninic acid method), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) concentrations (by enzyme-linked immunosorbent assay). The animals were then sacrificed, and lung tissue specimens were harvested for microscopic examination of the pathological changes (with a transmission electron microscope) and for determination of wet/dry weight (W/D) ratio, contents of iron, malondialdehyde (MDA) and glutathione (GSH) (by chemical colorimetric) and expression of nuclear Nrf2, glutathione peroxidase 4 (GPX4) and acyl-CoA synthetase long-chain family member 4 (ACSL4) (by Western blot). Results:Compared with Sham group, the concentrations of protein, IL-6 and TNF-α in BALF, W/D ratio, and contents of Fe 2+ and MDA were significantly increased, GSH content was decreased, GPX4 expression was down-regulated, the expression of nuclear Nrf2and ACSL4 was up-regulated ( P<0.05), and the mitochondrial morphology of type Ⅱalveolar epithelial cells showed the characteristic changes of ferroptosis, including the presence of smaller mitochondria and reduced cristae in IR group.Compared with IR group, the concentrations of protein, IL-6 and TNF-α in BALF, W/D ratio, and contents of Fe 2+ and MDA were significantly decreased, GSH content was increased, the expression of nuclear Nrf2 and GPX4 expression was up-regulated, ACSL4 expression was down-regulated ( P<0.05), and the pathological changes of lung tissues were significantly attenuated in IR+ SFP group. Conclusions:Nrf2 can inhibit ferroptosis during lung I/R and is involved in the endogenous protective mechanism in rats.
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Objective:To evaluate the role of adenosine monophosphate-dependent protein kinase/p38 mitogen-activated protein kinase/nuclear factor E2-associated factor 2 (AMPK/p38 MAPK/Nrf2) pathway in myocardial ischemia-reperfusion (I/R) injury in diabetic rats.Methods:Clean-grade healthy Sprague-Dawley male rats, aged 2-3 months, weighing 220-280 g, were fed with a high fat diet, and 1% streptozotocin 50 mg/kg was intraperitoneally injected for 4 consecutive days to develop the model of diabetes mellitus.Thirty diabetic rats were divided into 3 groups ( n=10 each) using the random number table method: sham operation group (sham group), myocardial I/R group (I/R group), and AMPK inhibitor compound C+ myocardial I/R group (C+ I/R group). The model of myocardial I/R injury was developed by ligation of the left anterior descending coronary artery for 30 min followed by 120 min reperfusion.Compound C 0.5 mg/kg was injected via the caudal vein at 30 min before ischemia in C+ I/R group, while the equal volume of normal saline was given instead in Sham group and I/R group.At 120 min of reperfusion, the percentage of myocardial infarct size was calculated, the serum concentrations of creatine kinase isoenzymes (CK-MB) and lactic dehydrogenase (LDH) were determined by enzyme-linked immunosorbent assay, the levels of glutathione (GSH), superoxide dismutase (SOD) and reactive oxygen species (ROS) in myocardial tissues were measured by enzyme-linked immunosorbent assay, and the expression of AMPK, phosphorylated AMPK (p-AMPK), phosphorylated p38 MAPK (p-p38 MAPK), Nrf2 and heme oxygenase-1 (HO-1) in myocardium was determined by Western blot. Results:Compared with Sham group, the percentage of myocardial infarct size and serum CK-MB and LDH levels were significantly increased, the levels of GSH and SOD in myocardial tissues were decreased, ROS level was increased, and the expression of AMPK, p-AMPK, p-p38 MAPK, Nrf2 and HO-1 was up-regulated in I/R group ( P<0.05). Compared with I/R group, the percentage of myocardial infarct size and serum CK-MB and LDH levels were significantly increased, the levels of GSH and SOD in myocardial tissues were decreased, ROS level was increased, and the expression of AMPK, Nrf2 and HO-1 was down-regulated in C+ I/R group ( P<0.05). Conclusions:AMPK/p38 MAPK/Nrf2 signaling pathway is involved in the mechanism of endogenous antioxidant stress during myocardial I/R in diabetic rats.
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Objective:To evaluate the effects of hydrogen-rich saline on acute lung injury in rats with traumatic brain injury (TBI) and the role of nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1 (HO-1) signaling pathway.Methods:Forty-eight adult male Sprague-Dawley rats, weighing 220-250 g, were divided into 4 groups ( n=12 each) using a random number table method: sham operation group (S group), TBI group (T group), TBI plus hydrogen-rich saline group (T+ H group), and TBI plus hydrogen-rich saline plus brusatol group (T+ H+ B group). TBI model was developed by controlled cortical impact.Nrf2 inhibitor brusatol 0.4 mg/kg was intraperitoneally injected every other day starting from 10 days before development of TBI model in T+ H+ B group.Hydrogen-rich fluid 10 ml/kg was intraperitoneally injected at 1 and 6 h after development of TBI model in T+ H group and T+ H+ B group.At 24 h after development of TBI model, the bronchoalveolar lavage fluid (BALF) was collected to detect the concentration of protein, blood samples from the right common carotid artery were collected and lung tissues were obtained for determination of the levels of tumor necrosis factor-alpha (TNF-α), interleukin-10 (IL-10) and high-mobility group box 1 protein (HMGB1) in serum and lung tissues (by enzyme-linked immunosorbent assay), wet to dry lung weight ratio (W/D ratio), expression of nuclear-Nrf2, total-Nrf2 and HO-1 in lung tissues (by Western blot), and expression of HO-1 mRNA (by real-time polymerase chain reaction) and for microscopic examination of histopathologic changes (by haematoxylin and eosin staining) which were scored. Results:Compared with S group, the concentrations of protein in BALF, W/D ratio of lung tissues and lung injury score were significantly increased, the levels of TNF-α, HMGB1 and IL-10 in serum and lung tissues were increased, and the expression of nuclear Nrf2, total Nrf2 and HO-1 protein and mRNA in lung tissues was up-regulated in T and T+ H groups ( P<0.05). Compared with T group, the concentrations of protein in BALF, W/D ratio of lung tissues and lung injury score were significantly decreased, the levels of TNF-α and HMGB1 in serum and lung tissues were decreased, the level of IL-10 in serum and lung tissues was increased, and the expression of nuclear Nrf2, total Nrf2 and HO-1 protein and mRNA in lung tissues was up-regulated in T+ H group ( P<0.05), and no significant changes were found in the parameters mentioned above in T+ H+ B group ( P>0.05). Compared with T+ H group, the concentrations of protein in BALF, W/D ratio of lung tissues and lung injury score were significantly increased, the levels of TNF-α and HMGB1 in serum and lung tissues were increased, the level of IL-10 in serum and lung tissues was decreased, and the expression of nuclear Nrf2, total Nrf2 and HO-1 protein and mRNA in lung tissues was down-regulated in T+ H+ B group ( P<0.05). Conclusions:Hydrogen-rich solution can alleviate acute lung injury in rats with traumatic brain injury, and the mechanism is related to activation of Nrf2/HO-1 signaling pathway and inhibition of the inflammatory responses.