In vitro inhibition of carnosic acid against influenza A virus infections / 药学学报

Carnosic acid (CA) is the main phenolic diterpenoid active ingredient in plants such as rosemary and sage, and has antiviral, antioxidant, anti-inflammatory effects and so on, however, its antiviral activity against influenza virus infections was not reported. In this study, antiviral activities against influenza A virus infections of three main bioactive ingredients from rosemary, including rosmarinic acid, CA and ursolic acid, were evaluated using virus titer titration assay, and CA showed remarkable inhibition on influenza H5N1 replication in A549 cells. The antiviral activity of CA was further confirmed and its mechanism of action was investigated using the indirect immunofluorescence assay (IFA), Western blot and real-time fluorescence quantification polymerase chain reaction (qRT-PCR). The results showed that the 50% effective concentration (EC50) of CA against influenza H5N1 in A549 cells and MDCK cells were 4.30 and 3.64 μmol·L-1, respectively. Meanwhile, CA also showed inhibition on influenza virus 2009panH1N1 (EC50: 10.1 μmol·L-1) and H3N2 (EC50: 12.8 μmol·L-1) replications in A549 cells. Mechanistic studies showed that antiviral activity of CA is related to its induction of heme oxygenase-1 (HO-1) in A549 cells and suppression on production of reactive oxygen in H5N1-infected cells.

Red light-emitting diode light mediated by the KEAP1-NRF2/HO-1 pathway induces osteogenic differentiation and attenuates the oxidative stress damage of human periodontal ligament stem cells induced by high glucose / 口腔疾病防治

Objective@# To explore the effects of red LED light mediated by the Kelch-like ECH-associated protein 1-nuclear factor erythroid 2-related factor 2/heme oxygenase-1 (KEAP1-NRF2/HO-1) pathway on osteogenic differentiation and oxidative stress damage of human periodontal ligament stem cells (hPDLSCs) induced by high glucose, which provides a basis for the application of red light-emitting diode (LED) light in cell antioxidative damage.@*Methods@#hPDLSCs were identified by flow cytometric analysis, alkaline phosphatase (ALP) staining and Alizarin red-S staining; hPDLSCs were pretreated in a high glucose environment for 48 hours and irradiated with 1, 3, or 5 J/cm2 red LED light. A CCK-8 assay was performed to choose the radiant exposure that had the strongest effect on promoting the cell proliferation rate for subsequent experiments. hPDLSCs were divided into a control group, a high glucose group and a high glucose+light exposure group. ALP staining, ALP activity, Alizarin red-S staining and quantitative calcified nodules were used to detect the osteogenic differentiation of hPDLSCs; qRT-PCR and Western blot were used to detect the gene and protein expression levels of ALP, runt-related transcription factor 2 (RUNX2) and osterix (OSX); the relative mRNA expression levels of antioxidant enzyme-related genes superoxide dismutase 2 (SOD2) and catalase (CAT) in hPDLSCs were detected by qRT-PCR; reactive oxygen species (ROS) levels were detected by fluorescence microscopy and flow cytometry; the tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) levels in cell supernatants were detected by ELISA; the NRF2-specific inhibitor ML385 was used to inhibit the NRF2 pathway; ALP staining and ALP activity were used to detect the markers of early osteogenic differentiation; qRT-PCR was used to detect the gene expression of ALP, RUNX2 and OSX; and the protein expression levels of KEAP1, NRF2 and HO-1 were detected by Western blot.@*Results @# Identified, and irradiant exposure of 5 J/cm2 was chosen for subsequent experiments. Red LED light irradiation (5 J/cm2) improved the osteogenic differentiation of hPDLSCs induced by high glucose (P<0.05), increased the mRNA and protein levels of ALP, RUNX2 and OSX (P<0.05), upregulated the mRNA expression levels of SOD2 and CAT (P<0.05), reduced the levels of ROS (P<0.05), and reduced TNF-α and IL-1β levels in the cell supernatants (P<0.05). When ML385 was added to inhibit the NRF2 pathway, the ALP activity of cells was decreased (P<0.05); the gene expression levels of ALP, RUNX2 and OSX were downregulated (P<0.05); the protein level of KEAP1 was upregulated (P<0.05); and the protein levels of NRF2 and HO-1 were downregulated (P<0.05)@*Conclusion@#Red LED light may promote the proliferation and osteoblastic differentiation of hPDLSCs induced by high glucose through the KEAP1-NRF2/HO-1 pathway and reduce the oxidative stress damage to hPDLSCs induced by high glucose.

Role of the nuclear factor erythroid 2-related factor 2/heme oxygenase-1 signaling pathway in alcoholic liver disease / 临床肝胆病杂志

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.

Effect and mechanism of Reduning injection on influenza A virus / 药学学报

The purpose of this study is to investigate the effect of Reduning injection (RI) on influenza A virus (IAV) and its mechanism. We evaluated the cytotoxicity of RI in A549 and MDCK cells by cell counting kit-8 (CCK-8) assay. Western blot and cytopathic effect (CPE) assays were applied to test the effects of RI on viral protein, CPE and virus virulence to evaluate its inhibitory effect. The proteins level of heme oxygenase 1 (HO-1), nuclear factor erythroid 2-related factor 2 (Nrf2), phosphorylation of P38 mitogen-activated protein kinases (MAPK) and extracellular signal-regulated kinases 1/2 (ERK1/2) were detected by Western blot. Real-time fluorescence quantitative PCR (qRT-PCR) was used to detect the RNA expression of interferon-α/β (IFN-α/β). The relative luciferase reporter assay was used to analyze the promoter activity and transcriptional regulation of Nrf2. The results indicated that RI inhibited IAV-induced MDCK cytopathies in a dose-dependent manner, decreased M2 protein of influenza virus and viral titer, indicating that it has definite effect on inhibiting IAV. RI promotes the phosphorylation of P38 MAPK and ERK1/2, activates the activity of Nrf2 nuclear transcription factor, increases the expression of Nrf2 protein in the nucleus, thus up-regulates the expression of HO-1 protein, and ultimately increases the IFN-α/β mRNA level. In summary, our results demonstrated that RI inhibits the replication of IAV by activating MAPK/Nrf2/HO-1 signaling pathway, revealing a new mechanism of RI against influenza virus, and providing theoretical basis for clinical treatment of influenza virus.

Effect of Glycyrrhizae Radix et Rhizoma-containing Serum on LPS-induced Inflammation in Caco2 Cells Based on Inhibition of Ferroptosis by Nrf2/HO-1 Pathway / 中国实验方剂学杂志

ObjectiveTo investigate the effect of Glycyrrhizae Radix et Rhizoma （GR）-containing serum on lipopolysaccharide （LPS）-induced inflammation in human colon epithelial adenocarcinoma cells （Caco2） based on inhibition of ferroptosis by the nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） pathway. MethodCaco2 cells were divided into a normal group， a model group （LPS， 200 μg·L-1）， low-， medium-， and high-dose GR-containing serum groups （5%， 10%， 20%）， and a ferroptosis inhibitor group （3-amino-4-cyclohexylamino-benzoic acid ethyl ester， Fer-1， 10 μmol·L-1）. The cells in the normal group were cultured normally， while those in other groups underwent the induction of an inflammation model. The cells in the low-， medium-， and high-dose GR-containing serum groups were treated with 5%， 10%， and 20% GR-containing serum for 24 hours， respectively， and the cells in the ferroptosis inhibitor group were treated with Fer-1 for 24 hours. Transmission electron microscopy was used to observe mitochondrial morphology in each group. Flow cytometry was used to detect intracellular Fe2+ levels. Microplate assays were performed to measure superoxide dismutase （SOD） activity， malondialdehyde （MDA） and glutathione peroxidase （GSH-Px） levels. Enzyme-linked immunosorbent assay （ELISA） was used to measure interleukin-1β （IL-1β）， IL-6， IL-10， and tumor necrosis factor-α （TNF-α） levels. Western blot was used to measure the expression levels of Nrf2， HO-1， ferritin heavy chain 1 （FTH1）， and glutathione peroxidase 4 （GSH-Px4） proteins. Small interfering RNA （siRNA） was used to investigate the role of Nrf2 in ferroptosis regulation. The cells after interference were divided into a negative control （NC） group， a Si-Nrf2 group， a GR-containing serum （20%） + Si-Nrf2 group， and a GR-containing serum （20%） + NC group. Microplate assays were performed to measure MDA， SOD， and GSH-Px levels， and Western blot was used to measure the expression levels of Nrf2， HO-1， FTH1， and GSH-Px4 proteins. ResultCompared with the normal group， the model group showed mitochondrial contraction， increased mitochondrial membrane thickness， and smaller mitochondrial morphology， increased Fe2+ content （P<0.01）， blunted SOD activity （P<0.01）， decreased GSH-Px expression （P<0.01）， increased MDA content （P<0.01）， reduced expression levels of Nrf2 and HO-1 （P<0.05）， reduced FTH1 expression （P<0.01）， and down-regulated GSH-Px4 expression （P<0.01）. In the GR-containing serum groups， the medium- and high-dose groups showed a significant decrease in Fe2+ content （P<0.01）， potentiated SOD and GSH-Px activities （P<0.01）， and decreased MDA levels （P<0.01）. The high-dose group showed a significant increase in Nrf2 expression （P<0.05）， and the medium-dose group showed increased expression of HO-1 and GSH-Px4 proteins （P<0.05）. The expression levels of FTH1 significantly increased in the low-， medium-， and high-dose groups （P<0.01）. The study on mechanism revealed that compared with the NC group， the cells transfected with Nrf2 siRNA showed increased MDA content （P<0.01）， blunted SOD activity （P<0.01）， decreased GSH-Px activity （P<0.01）， decreased expression of Nrf2 and HO-1 （P<0.01）， and reduced levels of FTH1 and GSH-Px4 proteins （P<0.01）. Compared with the Si-Nrf2 group， the cells treated with GR-containing serum showed a decrease in MDA content （P<0.01）， an increase in SOD activity （P<0.01）， an increase in GSH-Px activity （P<0.01）， increased expression of Nrf2 and FTH1 proteins （P<0.05）， and higher expression levels of HO-1 and GSH-Px4 proteins （P<0.01）. ConclusionGR-containing serum can reduce the inflammatory cytokines and oxidative stress levels in LPS-induced Caco2 cells. Its mechanism is related to the promotion of Nrf2/HO-1 signaling pathway expression， alleviating intracellular lipid peroxidation and inhibiting ferroptosis.

Role of Nrf2/HO-1 Signaling Pathway in Myocardial Infarction and Traditional Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Myocardial infarction （MI） is a common cardiovascular disease in clinical practice and one of the main causes of cardiovascular mortality. Its pathogenesis is complex and associated with oxidative stress reactions. Nuclear factor E2-related factor 2 （Nrf2） is a key factor in regulating oxidative stress reactions. It can regulate the expression of heme oxygenase-1 （HO-1）， playing a role in maintaining the oxidative-reductive homeostasis in the body. During the course of MI， the biological activity and levels of Nrf2 and HO-1 decrease， leading to weakened tissue antioxidant and anti-inflammatory capabilities， endothelial damage in myocardial blood vessels， release of vascular cell adhesion factors， and impaired endothelial function. In recent years， many basic research studies have explored the role and mechanisms of traditional Chinese medicine （TCM） in treating MI by modulating the Nrf2/HO-1 signaling pathway. The results have indicated that the Nrf2/HO-1 signaling pathway is an important potential target for TCM in the treatment of MI. This article reviewed the mechanism of the Nrf2/HO-1 signaling pathway in MI and the research progress of TCM in targeting and regulating this pathway， aiming to provide a theoretical basis for the prevention and treatment of MI and further drug development.

Effect and mechanism of safranal in a mouse model of sepsis-related liver injury induced by lipopolysaccharide / 临床肝胆病杂志

‍ 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.

Correlation between serum nesfatin-1, apelin and HO-1 levels and the severity of diabetic retinopathy / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To analyze the correlation between serum nesfatin-1, apelin and heme oxygenase-1(HO-1)levels and the severity of diabetic retinopathy(DR).METHODS:Totally 100 patients with type 2 diabetes mellitus(T2DM)who were admitted to the hospital from September 2020 to September 2022 were selected. They were divided into non-DR(NDR)group(35 cases), nonproliferative DR(NPDR)group(33 cases)and proliferative DR(PDR)group(32 cases)according to the condition of fundus lesions. Another 30 healthy individuals who received health check-ups in the hospital during the same period were selected as the control group. Serum nesfatin-1, apelin and HO-1 levels in each group were detected, and panretinal ischemia index(ISI)was evaluated.RESULTS:Serum nesfatin-1 and HO-1 levels in the T2DM patients were lower, and apelin level was higher as compared with the control group. The levels of nesfatin-1 and HO-1 in the PDR group were the lowest, while the apelin level was the highest. Panretinal ISI in the PDR group was higher than that in the NPDR group(4.56±0.57 vs. 2.05±0.29, P&#x0026;#x003C;0.05). Correlation analysis found that serum nesfatin-1 and HO-1 levels were negatively correlated with panretinal ISI in patients with DR, while apelin level was positively correlated with panretinal ISI. The receiver operator characteristic(ROC)curve analysis found that the areas under the curves of serum nesfatin-1, apelin and HO-1 for predicting PDR were 0.842, 0.833 and 0.807 respectively.CONCLUSION:Serum nesfatin-1, apelin and HO-1 levels are closely related to the severity of DR. Dynamic monitoring of serum nesfatin-1, apelin and HO-1 levels is important for the early detection of PDR.

Role of Nrf2/HO-1 signaling pathway in edaravone-induced attenuation of long-term cognitive impairment caused by long-time sedation with propofol in neonatal rats / 中华麻醉学杂志

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.

Effect of diosmetin on ferroptosis of hippocampal cells in rats with bacterial meningitis and the mechanism of SIRT1-Nrf2 signaling pathway / 中华行为医学与脑科学杂志

Objective:To explore the effect and mechanism of diosmetin (Dio) on neuronal ferroptosis in rats with bacterial meningitis (BM).Methods:Male SD rats aged 6-7 weeks of SPF grade were selected for the experiment. The BM model was established by injecting group B hemolytic streptococcus into the cisterna magna of cerebellum. Sixty BM model rats were successfully modeled and divided into model group, low-dose Dio group, medium-dose Dio group, high-dose Dio group and inhibitor group according to the random number table method, with 12 rats in each group. Another 12 weight-matched rats were taken as the control group.The rats in the low-dose Dio group, medium-dose Dio group, high-dose Dio group and the inhibitor group were intragastrically administered with Dio at 50 mg/kg, 100 mg/kg, 200 mg/kg and 200 mg/kg, respectively. The rats in the control group were intragastrically administered with an equal volume of 0.9 % sodium chloride solution. On the day of intragastric administration, the rats in the inhibitor group were intraperitoneally injected with SIRT1 pathway inhibitor EX527 (10 mg/kg), and the rats in the other groups were injected with an equal volume of 0.9% sodium chloride solution. The above interventions were performed once a day for 28 consecutive days. Loeffler neurological score was used to evaluate the neurological impairment in rats. Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in cerebrospinal fluid of rats were detected by ELISA. The number of white blood cells in cerebrospinal fluid was detected by a blood cell analyzer. Glutathione (GSH) was detected by micro-enzyme labeling method, malondialdehyde (MDA) was detected by thiobarbituric acid colorimetric method, reactive oxygen species(ROS) was detected by colorimetry, and Fe 2+ level was detected by ferrozine method. Hematoxylin-eosin staining, Prussian blue staining and TUNEL staining were used to observe the pathological damage, iron accumulation and apoptosis in the hippocampus, respectively.Western blot was applied to measure the expression of transferrin (Tf), proliferating cell nuclear antigen (PCNA), Bcl-2-associated X protein (Bax), caspase-3 and SIRT1/Nrf2/HO-1/Gpx4 signaling pathway proteins. Graphpad Prism 9.0 was used for data analysis. One-way ANOVA was used for statistical analysis, and SNK- q test was used for further pairwise comparisons. Results:(1) There was a statistically significant difference in neurological function scores among the 6 groups of rats ( F=125.451, P<0.001). The neurological function score of the model group was lower than that of control group, while the neurological function scores of the low-dose Dio group, medium-dose Dio group, and high-dose Dio group were higher than those of the model group (all P<0.05). The neurological function score of the inhibitor group ((2.57±0.26)) was lower than that of high-dose Dio group ((4.34±0.48)) ( P<0.05). (2) There were statistically significant differences in the levels of IL-6, TNF-α and the number of white blood cells in the cerebrospinal fluid of rats among the 6 groups ( F=127.817, 102.413, 180.967, all P<0.001). The levels of IL-6, TNF-α and the number of white blood cells in model group were higher than those of control group(all P<0.05). The levels of IL-6, TNF-α and the number of white blood cells in low-dose Dio group, medium-dose Dio group and high-dose Dio group were lower than those of model group (all P<0.001), and those in inhibitor group were all higher than those in high-dose Dio group(all P<0.001). (3) There were statistically significant differences in iron deposition rate and neuronal apoptosis rate among the 6 groups of rats ( F=90.857, 88.835, both P<0.001). The iron deposition rate ((18.37±3.14)%) and neuronal apoptosis rate ((27.58±2.63)%) in the inhibitor group were higher than those in the high-dose Dio group ((6.35±1.08)%, (14.02±1.87)%) (both P<0.05). (4) The levels of GSH, ROS, MDA, and Fe 2+ in the hippocampus of the 6 groups of rats showed statistically significant differences ( F=54.465, 106.453, 55.969, 105.457, all P<0.001). The GSH content in the inhibitor group ((103.48±8.76) mmol/g) was lower than that in the high-dose Dio group ((133.97±10.54) mmol/g), while the contents of ROS, MDA, Fe 2+ ((225.17±16.32) μmol/mg, (10.73±1.58) μmol/mg, (62.71±5.43) μg/g) were higher than those of the high-dose Dio group ((131.87±11.67) μmol/mg, (4.35±0.87) μmol/mg, (34.86±2.95) μg/g) (all P<0.05). (5)There were statistically significant differences in the protein levels of Tf, PCNA, Bax, caspase-3, SIRT1, Nrf2, HO-1 and Gpx4 in the hippocampus of the 6 groups of rats ( F=120.179, 107.568, 157.265, 98.031, 90.932, 52.283, 59.424, 114.539, all P<0.001). The protein levels of Tf, Bax and caspase-3 in the hippocampus of inhibitor group were higher than those of the high-dose Dio group, while the protein levels of PCNA, SIRT1, Nrf2, HO-1, Gpx4 were lower than those of the high-dose Dio group (all P<0.05). Conclusion:Diosmetin can activate SIRT1/Nrf2/HO-1/Gpx4 signaling pathway, thereby inhibiting neuronal ferroptosis in BM rats.

Effect of SIRT1 regulating Nrf2/HO-1 signaling pathway on sepsis-induced acute lung injury / 中华危重病急救医学

Objective:To investigate whether silence information regulator 1 (SIRT1) could regulate nuclear factor E2-related factor 2/heme oxygenase 1 (Nrf2/HO-1) signaling pathway and its role in acute lung injury (ALI) in sepsis rats.Methods:Twenty-four male Sprague-Dawley (SD) rats were randomly divided into sham operation group (Sham group), cecal ligation and puncture (CLP) induced sepsis group (CLP group), sepsis+SIRT1 specific agonist group (CLP+SRT1720 group,10 mg/kg SRT1720 was intraperitoneally injected 2 hours before CLP), sepsis+SIRT1 specific inhibitor group (CLP+EX527 group, 10 mg/kg EX527 was intraperitoneally injected 2 hours before CLP), with 6 rats in each group. The rats were killed 24 hours after modeling and their lung tissues were taken for pathological score (Smith score), superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), 8-hydroxydeoxyguanosine (8-OHdG), tumor necrosis factor-α (TNF-α), interleukins (IL-6, IL-1β), and SIRT1, Nrf2 and HO-1 mRNA and protein expression were detected.Results:The lung tissue of the CLP group mice was severely damaged, the alveolar interval was widened and a large number of inflammatory cells infiltrated, and there was visible pulmonary capillary hyperemia. The Smith score, the levels of TNF-α, IL-6, IL-1β, MDA and 8-OHdG were significantly increased, the levels of SOD, GSH, SIRT1, Nrf2 and HO-1 were significantly decreased in CLP group. After using SIRT1 specific agonist, the lung injury in CLP+SRT1720 group was significantly alleviated compared with that in CLP group, Smith score and lung tissue TNF-α, IL-6, and IL-1β levels were significantly decreased [Smith score: 2.83±0.75 vs. 5.67±0.52, TNF-α (ng/L): 36.78±5.36 vs. 66.99±5.44, IL-6 (ng/L): 23.97±3.76 vs. 45.70±4.16, IL-1β (ng/L): 16.76±1.39 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content increased [SOD (kU/g): 115.88±3.31 vs. 101.65±1.09, GSH (μmol/g): 8.42±0.81 vs. 5.74±0.46, both P < 0.05], MDA and 8-OHdG contents decreased [MDA (μmol/g): 5.24±0.33 vs. 9.86±0.66, 8-OHdG (ng/L): 405.76±8.54 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were increased [SIRT1 mRNA (2 -ΔΔCT): 1.49±0.15 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 1.19±0.08 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 1.80±0.41 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 1.03±0.06 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 1.14±0.10 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 1.01±0.11 vs. 0.73±0.03, all P < 0.05]. The lung injury in CLP+EX527 group was more severe than that in CLP group, Smith score and lung tissue TNF-α, IL-6, IL-1β levels were significantly increased [Smith score: 8.00±0.89 vs. 5.67±0.52, TNF-α (ng/L): 87.15±4.23 vs. 66.99±5.44, IL-6 (ng/L): 66.79±2.93 vs. 45.70±4.16, IL-1β (ng/L): 58.99±2.12 vs. 39.64±2.59, all P < 0.05], SOD activity and GSH content decreased [SOD (kU/g): 72.84±3.85 vs. 101.65±1.09, GSH (μmol/g): 3.30±0.67 vs. 5.74±0.46, both P < 0.05], the contents of MDA and 8-OHdG were increased [MDA (μmol/g): 14.14±0.70 vs. 9.86±0.66, 8-OHdG (ng/L): 927.66±11.47 vs. 647.12±10.64, both P < 0.05], the mRNA and protein expressions of SIRT1, Nrf2 and HO-1 were decreased [SIRT1 mRNA (2 -ΔΔCT): 0.40±0.07 vs. 0.64±0.03, Nrf2 mRNA (2 -ΔΔCT): 0.48±0.07 vs. 0.84±0.02, HO-1 mRNA (2 -ΔΔCT): 0.27±0.14 vs. 0.64±0.11, SIRT1 protein (SIRT1/β-actin): 0.20±0.05 vs. 0.52±0.05, Nrf2 protein (Nrf2/β-actin): 0.45±0.01 vs. 0.63±0.05, HO-1 protein (HO-1/β-actin): 0.36±0.08 vs. 0.73±0.03, all P < 0.05]. Conclusions:In the rat model of ALI induced by sepsis, SIRT1 can regulate the activation of Nrf2/HO-1 signaling pathway, upregulate the expression of downstream antioxidant enzymes, reduce oxidative stress injury, and then alleviate the ALI induced by sepsis in rats.

Protective effect of proanthocyanidins on neurotoxicity of benzoapyrene / 环境与职业医学

Background Benzo[a]pyrene (BaP) is neurotoxic and can cause neuronal damage by oxidative stress. Proanthocyanidin (PC) has antioxidant activity, and its mechanism may related to nuclear factor-erythroid 2-related factor 2 (Nrf2)-heme oxygenase-1 (HO-1) signaling pathway. Objective To explore potential protective effect of PC on hippocampal neuron injury induced by BaP oxidative stress. Methods Hippocampal neurons of neonatal SD rats delivered within 24 h were isolated and cultured, and cell activity was detected by cell counting kit-8 (CCK-8) method. According to the pre-experimental results, a control group and three BaP groups of 10, 20 and 40 µmol·L−1 were set up for Stage I experiment. The length of neurites and number of branches of hippocampal neurons in each group were observed by immunofluorescence method. Reactive oxygen species (ROS) fluorescence probe method was used to measure ROS levels in cells. Real-time quantitative fluorescent polymerase chain reaction (qRT-PCR) and Western blotting were used to detect the mRNA and protein expression of Nrf2, Kelch-like epichlorohydrin associated protein-1 (Keap1), HO-1, B-cell lymphoma-2 (Bcl-2), and Bcl-2-associated X (Bax) in hippocampal neurons of each group, respectively. According to the results of Stage I experiment, three group were set up, including control group, BaP alone treatment group (BaP 20 µmol·L−1), and PC intervention group (BaP 20 µmol·L−1 + PC 2.5 µg·mL−1) for Stage II experiment, with the same protocol as Stage I. Results For Stage I experiment, compared with the control group, the 10, 20, and 40 µmol·L−1 BaP groups showed gradually shortened length of neurites [(177.60±3.49), (142.40±6.52), and (100.50±19.40) µm] (P<0.05) and decreased number of branches (8.00±1.00, 6.33±1.53, 4.33± 0.58) of hippocampal neurons (P<0.05); increased ROS production (2.38±0.33, 8.08±0.26, 9.86±0.19) (P<0.05); the qRT-PCR results showed that the mRNA expression levels of Nrf2 (0.35±0.03, 0.25±0.01, 0.13±0.03), Keap1 (0.70±0.01, 0.47±0.03, 0.15±0.02), HO-1 (0.77±0.02, 0.60±0.02, 0.32±0.01), and Bcl-2 (0.65±0.03, 0.47±0.02, 0.18±0.02) gradually decreased, and the mRNA expression level of Bax gradually increased (1.24±0.01, 2.25±0.15, 4.98±0.30) (P<0.05); the Western blotting results showed that the protein expression trends of Nrf2, Keap1, HO-1, Bcl-2, and Bax were consistent with the mRNA results. For Stage II experiment, compared with the BaP alone treatment group, the length of neurites in the PC intervention group became longer, (149.90±3.01) μm vs (202.00±4.45) μm (P<0.05), the number of branches increased, (4.67±0.58) vs (8.33±0.58) (P<0.05); the ROS production reduced, (10.81±0.63) vs (7.31±0.70) (P<0.05); the mRNA expression levels of Nrf2, Keap1, HO-1, and Bcl-2 increased (P<0.05), and the mRNA expression levels of Bax decreased (P<0.05); the Nrf2, Keap1, HO-1, and Bcl-2 protein expression levels increased (P<0.05), and Bax protein expression level decreased (P<0.05). Conclusion PC may exert neuroprotective effects by activating the Nrf2-HO-1 signaling pathway, inhibiting BaP-induced oxidative stress in neuronal cells, and reducing cytotoxicity.

The effect of heme oxygenase-1 on liver sinusoidal endothelial cells proliferation and pro-regeneration / 中华肝胆外科杂志

Objective:To investigate the effects of heme oxygenase-1 (HO-1) on hepatic sinusoidal endothelial cells (LSECs) proliferation, migration, and hepatocyte proliferation.Methods:Eighteen male C57BL/6 mouse aged 6-8 weeks old were underwent partial hepatectomy. Cell proliferation and HO-1 expression in residual liver tissue were detected by immunofluorescence histochemistry at 0 d, 2 d and 4 d after operation. In vitro, LSECs were transfected with adenovirus carrying HO-1 gene (HO-1 group), and the cells were transfected with empty vector adenovirus and the non-transfected cells were used as control. In addition, LSECs from different transfection groups were co-cultured with hepatocyte without contact to evaluate the effect of HO-1 expression on promoting hepatocyte proliferation. Western Blotting and RT-PCR were used to detect the protein and mRNA expression of HO-1, inhibitor of DNA binding and or differentiation (Id1), hepatocyte growth factor (HGF) and Wnt2. Cell proliferation was detected by EdU. The ability of cell migration was detected by Transwell migration assay.Results:Compared with 0 d after hepatectomy, LSECs proliferation and HO-1 expression within LSECs were increased significantly at 4 d after surgery. EdU positive rate of LSECs in HO-1 group (27.20±4.80)% was higher than that in empty vector group (12.47±3.30)% and non-transfected group (15.97±2.50)%. The number of LSECs migration in HO-1 group (258.70±36.56) was higher than that in empty vector group (122.00±38.16) and non-transfected group (107.70±30.01). The protein and mRNA expression level of HO-1, Id1, HGF and Wnt2 in HO-1 group were higher than that in empty vector group and non-transfected group. EdU positive rate of hepatocytes that co-cultured with LSECs in HO-1 group (18.33±2.52) % was higher than that in empty vector group (11.33±1.53)% and non-transfected group (11.7±2.08)%. The differences were statistically significant (all P<0.05). Conclusion:Up-regulation of HO-1 promoted LSECs proliferation and migration of, as well as up-regulation of HO-1 in LSECs enhanced the capacity of LSECs to promote hepatocyte proliferation.

Protective effect and mechanism of heme oxygenase-1 in atherosclerosis / 国际脑血管病杂志

Atherosclerosis is closely associated with vascular diseases such as ischemic stroke and ischemic heart disease. Its main pathological mechanisms include inflammatory cell infiltration, oxidative stress, and vascular endothelial dysfunction. As an endogenous antioxidant enzyme, heme oxygenase-1 (HO-1) plays an anti-inflammatory, antioxidant and vasodilating role in the process of atherosclerosis, which can inhibit the occurrence of atherosclerosis and prevent the progress of unstable plaques. This article reviews the protective effect and mechanism of HO-1 in atherosclerosis, and discusses the important significance of HO-1 as a potential therapeutic target for atherosclerotic diseases.

Rhamnus crenata leaf extracts exhibit anti-inflammatory activity via modulating the Nrf2/HO-1 and NF-κB/MAPK signaling pathways

Objective: To elucidate the potential anti-inflammatory mechanisms of Rhamnus crenata leaf extracts using RAW264.7 cells. Methods: We used 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay to measure cell viability. Nitric oxide (NO) production was measured using Griess reagent. Western blotting and RT-PCR assays were carried out for analyzing the protein and gene expressions of pro-inflammatory mediators, respectively. Moreover, PD98059 (ERK1/2 inhibitor), SB203580 (p38 inhibitor), SP600125 (JNK inhibitor), and BAY11-7082 (NF-κB inhibitor) were used to evaluate the anti-inflammatory mechanism of Rhamnus crenata leaf extract. Results: Rhamnus crenata leaf extracts significantly inhibited the production of the pro-inflammatory mediators such as NO, iNOS, COX-2, IL-1β, and TNF-α in lipopolysaccharide (LPS)-stimulated RAW264.7 cells. Rhamnus crenata leaf extracts also suppressed LPS-induced degradation of IκB-α and nuclear accumulation of p65, which resulted in the inhibition of NF-κB activation in RAW264.7 cells. Additionally, the extracts attenuated the phosphorylation of p38, ERK1/2, and JNK in LPS-stimulated RAW264.7 cells. Moreover, HO-1 expression induced by Rhamnus crenata leaf extracts was significantly downregulated by SB230580, PD98059, SP600125 and BAY11-7082. Conclusions: Rhamnus crenata leaf extract may upregulate HO-1 expression through inhibition of p38, ERK1/2, and NF-κB activation, which may contribute to the anti-inflammatory activity of the extracts. Rhamnus crenata leaf extracts may have great potential for the development of anti-inflammatory drugs to treat acute and chronic inflammatory diseases.

Role of Nrf2/HO-1 Signaling Pathway in Osteoporosis and Chinese Medicine Intervention： A Review / 中国实验方剂学杂志

Osteoporosis is a chronic skeletal disease characterized by low bone mass， destruction of bone tissue microarchitecture， and imbalance of bone homeostasis， leading to increased bone fragility and increased risk of fractures. Oxidative stress caused by the disruption of the balance between excess reactive oxygen species （ROS） and the anti-oxidative system is an important factor in the occurrence and progression of osteoporosis. Nuclear factor E2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） is an important anti-oxidative stress pathway. Nrf2 is a primary factor in regulating cellular oxidative stress. Activating Nrf2 can stimulate the expression of HO-1. HO-1 is a key enzyme whose metabolites are bile green Oxygen， carbon monoxide， and free iron. The metabolites can scavenge ROS， thereby exerting an antioxidant effect in cells. At present， domestic and foreign scholars have reported that the Nrf2/HO-1 signaling pathway is closely related to the occurrence and development of osteoporosis and the mechanism of drugs. Chinese medicine can effectively solve the insufficiency of western medicine with multi-target， multi-channel， and multi-level advantages. Chinese medicine can resist oxidative stress， inflammatory response， and apoptosis by regulating the Nrf2/HO-1 signaling pathway， thus treating osteoporosis. This article reviewed the relationship between Nrf2/HO-1 signaling pathway and its key target protein factors and osteoporosis， to clarify the important role of the Nrf2/HO-1 signaling pathway in osteoporosis. At the same time， a systematic summary of Chinese medicines targeting and regulating the Nrf2/HO-1 signaling pathway for the treatment of osteoporosis was conducted， to provide a theoretical basis for further precise treatment of osteoporosis.

Pin1 aggravates renal injury induced by ischemia and reperfusion in rats via Nrf2/HO-1 mediated endoplasmic reticulum stress

Purpose: To investigate the role of peptidyl-prolyl cis/trans isomerase 1 (Pin1) on renal ischemia-reperfusion (I/R) injury and underlying mechanism. Methods: By establishing the in vitro and in vivo models of renal I/R, the role of Pin1 was explored by using molecular assays. Results: In renal I/R, endogenous Pin1 level was up-regulated in I/R-impaired kidney. Suppression of Pin1 with juglone afforded protection against I/R-mediated kidney dysfunction, and reduced I/R-induced endoplasmic reticulum (ER) stress in vivo. Consistent with the in vivo results, repression of Pin1 with juglone or gene knockdown with si-Pin1 conferred cytoprotection and restricted hypoxia/reoxygenation (H/R)-driven ER stress in HK-2 cells. Simultaneously, further study uncovered that Nrf-2/HO-1 signals was the association between Pin1 and ER stress in response to renal I/R. In addition, Nrf-2/HO-1 signal pathway was inactivated after kidney exposed to I/R, as indicated by the down-regulation of Nrf-2/HO-1 levels. Furthermore, inhibition of Pin1 remarkably rescued the inactivation ofNrf-2/HO-1. Conclusions: Pin1 modulated I/R-mediated kidney injury in ER stress manner dependent on Nrf2-HO-1 pathway in I/R injury.

Effect of Buyang Huanwutang on Keap1/Nrf2/HO-1 Antioxidant Signaling Pathway in Rats with Idiopathic Pulmonary Fibrosis / 中国实验方剂学杂志

ObjectiveTo study the effect of Buyang Huanwutang on Kelch-like Ech-related protein 1 （Keap1）/nuclear factor E2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） antioxidant signaling pathway in rats with idiopathic pulmonary fibrosis （IPF） and explore the mechanism of this prescription in the treatment of IPF. MethodForty SPF-grade male SD rats were assigned into a sham operation group， a model group， a Buyang Huanwutang group， and a nintedanib group according to random number table method， with 10 rats in each group. IPF rat model was established by intratracheal infusion of bleomycin （0.005 g·kg-1） in other groups except the sham operation group. Buyang Huanwutang group was administrated with Buyang Huanwutang (14.84 g·kg-1)，intragastric administration of nitedanib suspension (0.1 g·kg-1)，sham operation group and model group were given equal volume of normal saline， for 28 days. After lung function test， serum and lung tissue samples were collected. Hematoxylin-eosin （HE） staining and Masson trichrome staining were employed to observe the pathological changes of the lung tissue. The content of hydroxyproline （HYP） in lung tissue was detected. The levels of malondialdehyde （MDA） in serum and lung tissue， and the activities of superoxide dismutase （SOD）， glutathione peroxidase （GSH-Px） and catalase （CAT） were determined. The mRNA and protein levels of Keap1， Nrf2， and HO-1 was determined by Real-time fluorescent quantitative polymerase chain reaction， immunohistochemical staining， and Western blot. ResultCompared with the sham operation group， the modeling increased the resistance and elasticity and decreased the compliance of respiratory system （P<0.01）， elevated the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and enriched MDA in serum and lung tissue， while it decreased the activities of SOD， GSH-Px， and CAT （P<0.01）. Furthermore， the modeling down-regulated the mRNA and protein levels of Keap1 and up-regulated those of Nrf2 and HO-1 in lung tissue （P<0.01）. Compared with the model group， Buyang Huanwutang decreased the resistance and elasticity and increased the compliance of respiratory system （P<0.01）， lowered the lung index， pathological score， and HYP content in lung tissue （P<0.01）， and reduced MDA in serum and lung tissue， while it increased the activities of SOD， GSH-Px， and CAT （P<0.01）. Additionally， Buyang Huanwutang down-regulated the expression of Keap1 and up-regulated that of Nrf2 and HO-1 in lung tissue （P<0.05， P<0.01）. ConclusionBuyang Huanwutang can activate Keap1/Nrf2/HO-1 signaling pathway to enhance the antioxidant capacity and slow down the pathological process of IPF in rats.

Protective Effects of Anthocyanins Extracted from Vaccinium Uliginosum on 661W Cells Against Microwave-Induced Retinal Damage / 中国结合医学杂志

OBJECTIVE@#To study the protective effect of anthocyanins extracted from Vaccinium Uliginosum (VU) on retinal 661W cells against microwave radiation induced retinal injury.@*METHODS@#661W cells were divided into 6 groups, including control, model [661W cells radiated by microwave (30 mW/cm2, 1 h)] and VU groups [661W cells pretreated with anthocyanins extracted from VU (25, 50, 100 and 200 µg/mL, respectively) for 48 h, and radiated by microwave 30 mW/cm2, 1 h]. After treatment with different interventions, the cell apoptosis index (AI) was determined using Heochst staining; contents of malonaldehyde (MDA), glutataione (GSH), and activity of superoxide dismutase (SOD) were measured. mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2) and heme oxygenase 1(HO-1) were detected by real time quantitative polymerase chain reaction, and the expression of HO-1 protein was examined by Western blot analysis. Nucleus and cytoplasm were separated and Nrf2 protein expression was further verified by Western blot analysis.@*RESULTS@#There was significant difference in AI among the groups (F=322.83, P<;0.05). Compared with the control group, AI was significantly higher in the model group and was lower in 4 VU-pretreated groups (P<;0.05). Linear regression analysis showed the decline of AI was in a dose-dependent manner with VU treatment (r=0.8419, P<;0.05). The MDA and GSH contents of 661W cells in VU-treated groups were significantly lower than the model group (P<;0.05). Compared with the model group, the SOD activity in the VU-treated groups (50, 100 and 200 µg/mL) was significantly higher (all P<;0.05). The Nrf2 and HO-1 mRNA expressions were slightly increased after irradiation, and obviously increased in 100 µg/mL VU-treated group. After irradiation, the relative expressions of HO-1 and Nrf2 proteins in nucleus were slightly increased (P<;0.05), and the changes in cytoplasm were not obvious, whereas it was significantly increased in both nucleus and cytoplasm in the VU treatment groups.@*CONCLUSIONS@#Anthocyanins extracted from VU could reduce apoptosis, stabilize cell membrane, and alleviate oxidant injury of mouse retinal photoreceptor 661W cells. The mechanism might be through activating Nrf2/HO-1 signal pathway and inducing HO-1 transcription and translation.

Abdominal puncture drainage alleviates severe acute pancreatitis in rats by activating Nrf-2/HO-1 pathway and promoting autophagy / 南方医科大学学报

OBJECTIVE@#To assess the effect of early abdominal puncture drainage (APD) on autophagy and Nrf-2/HO-1 pathway in rats with severe acute pancreatitis (SAP) and explore the possibile mechanism.@*METHODS@#Thirty-two male SD rats were randomly divided into sham-operated (SO) group, SAP group with retrograde injection of 4% sodium taurocholate, APD group with insertion of a drainage tube into the lower right abdomen after SAP induction, and APD + ZnPP group with intraperitoneal injection of 30 mg/kg ZnPP 12 h before APD modeling. Blood samples were collected from the rats 12 h after modeling for analysis of amylase and lipase levels and serum inflammatory factors. The pathological changes of the pancreatic tissue were observed with HE staining. Oxidative stress in the pancreatic tissue was detected with colorimetry, and sub-organelle structure and autophagy in pancreatic acinar cells were observed by transmission electron microscopy. The expressions of autophagy-related proteins and Nrf-2/HO-1 pathway were detected using RT-PCR and Western blotting.@*RESULTS@#Compared with those in SAP group, the rats with APD treatment showed significantly alleviated pathologies in the pancreas, reduced serum levels of lipase, amylase and inflammatory factors, lowered levels of oxidative stress, and activated expressions of Nrf-2/HO-1 pathway in the pancreas. The ameliorating effect of ADP was significantly inhibited by ZnPP treatment before modeling. APD obviously reversed mitochondrial and endoplasmic reticulum damages and p62 accumulation induced by SAP.@*CONCLUSION@#APD treatment can suppress oxidative stress and repair impaired autophagy in rats with SAP by activating the Nrf-2/HO-1 pathway, thereby reducing the severity of SAP.