Therapeutic potential of sulforaphane: modulation of NRF2 mediated PI3/AKT/mTOR pathway in oral fibrosis / Potencial terapêutico do sulforafano: modulação do NRF-2 mediado o pela via PI3/AKT/mTOR na fibrose oral

Oral Submucous Fibrosis is a potentially malignant disorder caused by habitual areca nut chewing, which contributes to the dispersion of active alkaloids into subepithelial tissues, stimulating excessive extracellular matrix deposition. Various treatment modalities are available; however, their efficacy in inhibiting fibrosis progression remains limited. Sulforaphane (SFN), an isothiocyanate found abundantly in cruciferous plants, is known to have effective antifibrotic properties. Objective: The present study investigated the antifibrotic effect of SFN via phosphatidylinositol 3 kinase (PI3K), Serine/Threonine Kinase 1 (AKT-1), mammalian target of rapamycin (mTOR) pathway in arecoline (AER) induced fibrosis in human gingival fibroblasts [HGFs]. Material and Methods: MTT assay determined the half-maximal inhibitory concentration of AER and SFN at 24h in the HGF cell line. Expression levels of transforming growth factor ß1 (TGFß1), collagen type 1 alpha 2 (COL1A2), hydroxyproline (HYP), PI3, AKT, mTOR, and nuclear factor erythroid 2­related factor 2 (NRF2) were assessed post-AER and SFN treatment using qPCR and western blot analysis. Results: The findings of the study revealed that AER elicited a stimulatory effect, upregulating TGFß1, COL1A2, HYP, PI3K, AKT, and mTOR and downregulating NRF2 expression. Conversely, SFN treatment significantly upregulated NRF2, inhibiting TGFß1 mediated PI3/AKT/mTOR pathway. Conclusion: These observations suggest that SFN can be used as a promising synergistic antifibrotic agent to combat fibrogenesis via the non-Smad pathway (AU)

Fibrose submucosa oral é uma desordem potencialmente maligna causada pelo habito de mascar a noz da areca, o que contribui para a dispersão de alcalóides ativos nos tecidos subepiteliais, estimulando a deposição excessiva de matriz extracelular. Há várias modalidades terapêuticas, no entanto, com eficácia limitada no controle da progressão da fibrose. O sulforafano (SFN), isotiocianato encontrado abundantemente em plantas crucíferas, é conhecido por suas propriedades antifibróticas. Objetivo: Investigar os efeitos antifibróticos do SFN na via fosfatidilinositol3-quinase (PI3K), via quinase serina/treonina 1 (AKT-1), via do alvo da rapamicina em mamíferos (mTOR), na fibrose induzida por arecolina (AER) em fibroblastos gengivais de humanos (HGFs). Material e Métodos: A meia concentração inibitória mínima de AER e SFN em 24 horas nas células HGFs foi determinada por MTT. Os níveis de expressão de ß1 (TGFß1), colágeno tipo 1 alfa 2 (COL1A2), hidroxiprolina (HYP), PI3K, AKT, mTOR, fator nuclear eritroide 2 relacionado ao fator 2 (NRF2) foram analisados após tratamento com ERA e SFN através de qPCR e western blot. Resultados: O ERA apresentou efeito estimulatório aumentando a expressão de TGFß1, COL1A2, HYP, PI3K, AKT e mTOR e diminuindo a expressão de NRF2. Por outro lado, tratamento com SFN aumentou significativamente a expressão de NRF2, inibindo a liberação de TGFß1 mediada pela via PI3/AKT/mTOR. Conclusão: Esses achados sugerem que o SFN pode ser um agente antifibrótico promissor no combate à fibrogênese decorrente da via não-Smad (AU)

Research Progress of Traditional Chinese Medicine Intervention in Nrf2/HO-1 Signaling Pathway for Acute Pancreatitis： A Review / 中国实验方剂学杂志

Acute pancreatitis （AP） is a common clinical acute abdominal disease， which is characterized by acute onset， rapid development， severe disease， many complications， and high mortality rate. It can progress to severe AP （SAP） if not treated promptly in the early stage. The pathogenesis of AP is complex and involves multiple cellular and molecular levels. It is now clear that oxidative stress and reactive oxygen species （ROS） production are involved in the physiopathological process of AP， which is associated with a low quantity and activity of antioxidant enzymes in pancreatic cells. Nuclear factor E2-related factor 2 （Nrf2） serves as the ''golden key'' to maintain redox homeostasis in tissue cells and constitutes an important signaling pathway for antioxidant response and inflammation in vivo by collaborating with downstream antioxidant enzymes such as heme oxygenase-1 （HO-1）. Traditional Chinese medicine has unique efficacy in treating diseases due to its multi-component， multi-target， multi-drug delivery， and multi-formulation characteristics. Based on the concept of synergy between traditional Chinese and Western medicine， traditional Chinese medicine is becoming a new craze in the treatment of AP. The level of oxidative stress and Nrf2/HO-1 signaling pathway in AP pancreatic tissue are in a dynamic change process， and the intervention of traditional Chinese medicine can clean ROS production， affect the inflammatory pathway， and reduce oxidative stress damage， so as to protect against pancreatic injury. This suggests that this pathway plays an important role in AP. This article reviews the recent literature on the regulation of the Nrf2/HO-1 signaling pathway by traditional Chinese medicine for AP and summarizes that the monomers of traditional Chinese medicine targeting this pathway are mainly heat-clearing and detoxifying， blood-activating and blood-stasis-removing， and Qi benefiting and middle warming， and the compounds of traditional Chinese medicine include Yinchenhao Decoction and QingYi Ⅱ， so as to provide a new direction for the prevention and treatment of AP and further drug development.

Phenolic constituents of Sanguisorba officinalis and their Nrf2 agonistic effect / 药学学报

Thirty-one phenolic constituents were isolated and purified from the 95% ethanol extract of Sanguisorbae Radix by using various chromatographic techniques, including macroporous resin, silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC. Their structures were elucidated by physicochemical properties, spectroscopic data (MS and NMR) and electronic circular dichroism (ECD) spectra, and identified as 3-methoxyl-2S,3S-epoxyflavanone (1a), 3-methoxyl-2R,3R-epoxyflavanone (1b), longifoin B (2), longifoin C (3), eriodictyol (4), naringenin (5), liquiritigenin (6), 5,3ʹ-dihydroxy-7,4ʹ-dimethoxyflavanone (7), naringenin-7-O-β-D-glucopyranoside (8), dihydroquercetin (9), dihydrokaempferol (10), (-)-garbanzol (11), (2R,3R)-4-methoxyl-distylin (12), kaempferol (13), quercetin (14), α,4,2′,4′-tetrahydroxydihydrochalcone (15), phloretin (16), (+)-catechin (17), ethyl (+)-cyanidan-3-ol-8-carboxylate (18), phyllocoumarin (19), methyl 3-methoxy-4,5-dihydroxybenzoate (20), 4,5-dimethoxy-3-hydroxybenzoic acid methyl ester (21), 3,4′-di-O-methylellagic acid (22), 3,4,3′-O-trimethylellagic acid (23), 3,3ʹ,4ʹ-O-trimethylellagic acid-4-O-β-D-xyloside (24), (3R)-thunberginol C (25), resveratrol (26), 1-hydroxypinoresinol (27), (7S,8S)-3-methoxy-3′,7-epoxy-8,4′-oxyneoligna-4,9,9′-triol (28), emodin-8-O-β-D-glucoside (29), phloracetophenone (30) and 4-(4′-hydroxyphenyl)-butan-2-one (31). Among them, compound 1a and 1b is a pair of new flavonoid enantiomers, compounds 2 and 3 are a pair of new epimers, while compounds 4, 5, 6, 9, 10, 13, 16 and 26 were obtained from S. officinalis for the first time, compounds 7, 8, 27, 30 and 31 were isolated for the first time from the S. officinalis genus, and compounds 11, 12, 15, 18, 19, 25, 28 and 29 were isolated for the first time from the Rosaceae. The antioxidant activities of compounds 1-24 were evaluated by activating the Nrf2 transcriptional pathway, which were measured by the dual-luciferase reporter gene assay in 293T cells. Compounds 4, 6-10, 12, 14, 17, 19, 20 and 22-24 showed significant Nrf2 agonistic effect compared with the control group at 25 μmol·L-1, which provided reference for the research of their antioxidant activity.

Effects of Guben Fangxiao Beverage （固本防哮饮） on Lung Tissue Oxidative Stress and AMPK/Nrf2/HO-1 Pathway in Mice with Bronchial Asthma in Remission / 中医杂志

ObjectiveTo investigate the possible mechanism of Guben Fangxiao Beverage （固本防哮饮） for the prevention and treatment of chronic airway inflammation during asthma remission. MethodsThirty-six female Balb/c mice were randomly divided into normal group， model group， low-， medium-， and high-dose of Guben Fangxiao Beverage group and montelukast sodium group， with 6 mice in each group. Except for the normal group， ovalbumin and respiratory syncytial virus were used in other groups to establish a mouse model of bronchial asthma in remission stage. After molding， the low-， medium-， and high-dose groups of Guben Fangxiao Beverage were respectively given 12， 24， and 36 g/（kg·d）， the montelukast sodium group was given montelukast sodium granule 2.6 mg/（kg·d）， and the mice in the normal group and model group were given 20 ml of double-distilled water， all by gavage， once a day for 28 days. The levels of interleukin 4 （IL-4） and interleukin 5 （IL-5） in the lung tissue of mice were detected； HE staining was used to observe the pathology of the lung tissue and to score the inflammation； DHE staining was used to observe the level of reactive oxygen species （ROS） in the lung tissue， and the activities of mitochondrial respiratory chain complexes Ⅰ， Ⅱ， Ⅲ， Ⅳ， and Ⅴ in the lung tissue were detected； the levels of serum superoxide dismutase （SOD）， catalase （CAT）， malondialdehyde （MDA） and adenosine triphosphate （ATP） were detected； the protein expression levels of phosphorylated adenosine monophosphate-activated protein kinase （p-AMPK）， nuclear factor erythroid 2-related factor 2 （Nrf2）， haem oxygenase 1 （HO-1） and cAMP responsive element binding protein （CREB） in the lung tissues of the model group were detected by Western blot. ResultsCompared with the normal group， the histopathological results of the lungs of mice in the model group showed an increase in inflammatory cells around the airways and an increase in inflammatory score； DHE staining showed an increase in the level of ROS， and an increase in the levels of IL-4 and IL-5 in the lung tissues； the levels of serum SOD， CAT， and ATP were reduced， and the level of MDA was elevated； the activities of the mitochondrial respiratory chain complexes Ⅰ， Ⅱ， Ⅲ， Ⅳ， and Ⅴ of the lung tissues were reduced， and the activities of p-AMPK， Nrf2， CREB protein expression decreased （P＜0.05）. Compared with the model group， the lung tissue inflammatory cells and inflammation scores of mice in each Guben Fangxiao Beverage dose group and montelukast sodium group were reduced； the levels of ROS， IL-4 and IL-5 in the lung tissue were reduced； the levels of CAT and ATP in the serum increased， and the content of MDA was reduced； and the activities of mitochondrial respiratory chain complexes Ⅰ and Ⅱ， as well as the expression of CREB protein， were elevated in the lung tissue （P＜0.05）. Compared with the high-dose group， the MDA level of the medium-dose Guben Fangxiao Beverage group decreased （P＜0.05）. The activity of mitochondrial respiratory chain complex V in the medium-dose group was higher than that in the montelukast sodium group， and the activity of mitochondrial respiratory chain complex Ⅳ in the medium- and high-dose groups was higher than that in the low-dose group （P＜0.05）. ConclusionGuben Fangxiao Beverage can inhibit oxidative stress and improve mitochondrial function to relieve chronic airway inflammation in bronchial asthma model mice during asthma remission， and its mechanism may be related to the activation of AMPK/Nrf2/HO-1 signaling pathway.

Earthworm Protein Protects Vascular Endothelial Function in Spontaneously Hypertensive Rats via PI3K/Akt/Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of earthworm protein on the expression of phosphatidylinositol 3-kinase/protein kinase B/nuclear factor E2-related factor 2 （PI3K/Akt/Nrf2） pathway in the aorta of spontaneously hypertensive rats （SHR） and explore mechanism of earthworm protein in treating hypertensive vascular endothelial dysfunction （VED）. MethodTen 10-week-old Wistar Kyoto （WKY） rats and fifty SHR rats were selected for a week of adaptive feeding. WKY rats were selected as the normal group， and fifty SHR rats were randomized according to body weight into model， valsartan （8×10-3 g·kg-1·d-1）， and high-， medium-， and low-dose （0.2， 0.1， 0.05 g·kg-1·d-1， respectively） earthworm protein groups. The normal and model groups were administrated with equal volume of double distilled water by gavage. During the drug intervention period， the general situations of rats in each group were observed and their blood pressure was monitored at specific time points every other week before and after administration. After 8 weeks of drug intervention， enzyme-linked immunosorbent assay was employed to measure the levels of angiotensin-Ⅱ （Ang-Ⅱ） and endothelin-1 （ET-1） in the serum of rats in each group. The corresponding kits were used to determine the levels of nitric oxide （NO）， malondialdehyde （MDA）， glutathione peroxidase （GPX）， superoxide dismutase （SOD）， and ferrous ion （Fe2+）. Hematoxylin-eosin （HE） staining was employed to observe the changes in the intima of the aorta. Fluorescence quantitative polymerase chain reaction （Real-time PCR） was employed to measure the mRNA levels of PI3K， Akt， Nrf2， heme oxygenase-1 （HO-1）， and glutathione peroxidase 4 （GPX4） in the aortic tissue. Western blotting was used to determine the protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the thoracic aorta. ResultCompared with the normal group， the model group had decreased body mass， increased irritability， severe endothelial damage， elevated blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， lowered NO level （P<0.01）， and down-regulated mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 in the aortic tissue （P<0.01）. Compared with the model group， drug intervention caused no significant change in the body mass， calmed the rats， alleviated the endothelial damage， lowered blood pressure and serum levels of Ang-Ⅱ， ET1， MDA， and Fe2+ （P<0.01）， elevated the NO level （P<0.05）， and up-regulated the mRNA and protein levels of p-PI3K （Tyr467/199）， PI3K， p-Akt （Ser473）， Akt， Nrf2， HO-1， and GPX4 （P<0.05）. ConclusionThe earthworm protein can exert antihypertensive effects by ameliorating VED in SHR. Specifically， it may regulate the PI3K/Akt/Nrf2 signaling pathway to inhibit oxidative stress and ferroptosis.

Buzhong Yiqitang Regulates Apoptosis via Nrf2/ROS Pathway to Alleviate Cisplatin Resistance in A549/DDP Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of Buzhong Yiqitang-containing serum in alleviating the cisplatin resistance in human non-small cell lung cancer （A549/DDP） cells via regulating the nuclear factor E2-related factor 2 （Nrf2）/reactive oxygen species （ROS） signaling pathway. MethodThe serum containing Buzhong Yiqitang was prepared and A549/DDP cells were cultured and randomly grouped： blank （10% blank serum）， cisplatin （10% blank serum+20 mg·L-1 cisplatin）， Buzhong Yiqitang （10% Buzhong Yiqitang-containing serum+20 mg·L-1 cisplatin）， ML385 （10% blank serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin）， Buzhong Yiqitang+ML385 （10% Buzhong Yiqitang-containing serum+5 μmol·L-1 ML385+20 mg·L-1 cisplatin）， tertiary butylhydroquinone （TBHQ） （10% blank serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin）， and Buzhong Yiqitang+TBHQ （10% Buzhong Yiqitang-containing serum+5 μmol·L-1 TBHQ+20 mg·L-1 cisplatin）. The median inhibitory concentration （IC50） of cisplatin in each group was determined by the cell counting kit-8 （CCK-8） method and the resistance index （RI） was calculated. The apoptosis rate was detected by flow cytometry. The ROS content of each group was determined with the DCFH-DA fluorescence probe. Western blot was employed to determine the protein levels of Nrf2， cleaved cysteinyl aspartate-specific protease-3 （cleaved Caspase-3）， cytochrome C （Cyt C）， and B-cell lymphoma-2 （Bcl-2）. ResultCompared with those in the cisplatin group， the IC50 and RI of A549/DDP cells to cisplatin in Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups decreased （P˂0.05）. Compared with the blank group， the cisplatin， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 groups showed increased apoptosis rate of A549/DDP cells （P˂0.05）. Compared with the blank group， cisplatin promoted the expression of Nrf2 （P˂0.05）. Compared with the cisplatin group， Buzhong Yiqitang， ML385， and Buzhong Yiqitang+ML385 inhibited the expression of Nrf2 （P<0.05）， elevated the ROS level （P˂0.05）， up-regulated the protein levels of cleaved Caspase-3 and Cyt C， and down-regulated the protein level of Bcl-2 （P<0.05）， which were the most significant in the Buzhong Yiqitang+ML385 group. Compared with the cisplatin group， the TBHQ group showed increased IC50 and RI of cisplatin （P<0.05）， decreased apoptosis rate of A549/DDP cells （P<0.05）， up-regulated protein levels of Nrf2 and Bcl-2 （P<0.05）， lowered level of ROS （P˂0.05）， and down-regulated protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. Compared with the TBHQ group， Buzhong Yiqitang+TBHQ decreased the IC50 and RI of cisplatin in A549/DDP cells （P<0.05）， increased the apoptosis rate （P<0.05）， down-regulated the protein levels of Nrf2 and Bcl-2 （P<0.05）， increased ROS （P˂0.05）， and up-regulated the protein levels of cleaved Caspase-3 and Cyt C （P<0.05）. ConclusionBuzhong Yiqitang induced apoptosis by inhibiting Nrf2/ROS pathway to alleviate cisplatin resistance in A549/DDP cells.

Celastrol targeting Nedd4 reduces Nrf2-mediated oxidative stress in astrocytes after ischemic stroke / 药物分析学报

Stroke is the second leading cause of death worldwide,and oxidative stress plays a crucial role.Celastrol exhibits strong antioxidant properties in several diseases;however,whether it can affect oxidation in cerebral ischemic-reperfusion injury(CIRI)remains unclear.This study aimed to determine whether celastrol could reduce oxidative damage during CIRI and to elucidate the underlying mechanisms.Here,we found that celastrol attenuated oxidative injury in CIRI by upregulating nuclear factor E2-related factor 2(Nrf2).Using alkynyl-tagged celastrol and liquid chromatography-tandem mass spectrometry,we showed that celastrol directly bound to neuronally expressed developmentally downregulated 4(Nedd4)and then released Nrf2 from Nedd4 in astrocytes.Nedd4 promoted the degradation of Nrf2 through K48-linked ubiquitination and thus contributed to astrocytic reactive oxygen species production in CIRI,which was significantly blocked by celastrol.Furthermore,by inhibiting oxidative stress and astrocyte activation,celastrol effectively rescued neurons from axon damage and apoptosis.Our study uncovered Nedd4 as a direct target of celastrol,and that celastrol exerts an antioxidative effect on as-trocytes by inhibiting the interaction between Nedd4 and Nrf2 and reducing Nrf2 degradation in CIRI.

Effects of the Nrf2 signaling pathway on the occurrence and development of cataract / 中华实验眼科杂志

Cataract is the leading cause of blindness worldwide, and the common mechanism for its onset and development is oxidative damage to the lens.The expression of a large number of antioxidant genes is regulated by nuclear factor erythroid 2-related factor 2 (Nrf2), and the Nrf2 oxidative defense system is one of the main defense systems for antioxidant damage in the body.The activity of Nrf2 signaling pathway is primarily regulated by Kelch-like ECH-associated protein 1 (Keap1), and Keap1 mediates Nrf2 protein degradation thereby inhibiting the activation of the Nrf2 pathway in a Keap1-dependent manner.Increasing research has revealed other mechanisms of Nrf2 regulation in a Keap1-independent manner, including phosphorylation and acetylation of Nrf2 (PKC, PI3K/Akt, JNK, and P300/CBP) and epigenetic factors (promoter methylation, histone modification, and microRNAs-144, -28 and -34). Reduced expression of Nrf2 and its downstream antioxidant genes has been shown to play an important role in the onset and development of various types of cataracts.Many compounds, such as morin, hyperoside, sulforaphane, rosae laevigatae extract, 3-n-butylphthalide, and acetyl-L-carnitine, have been found to be able to upregulate the expression of antioxidant genes by activating Nrf2 signaling pathway to protect lens epithelial cells from oxidative stress to prevent or alleviate cataract.This article reviewed recent researches on Nrf2 signaling pathway and the relationship between Nrf2 activators and cataract to provide a theoretical basis for the prevention and treatment of cataract.

Inhibitory effect of astaxanthin on oxidative stress damage in lens epithelial cells and its mechanism / 中华实验眼科杂志

Objective:To investigate the regulatory effect of astaxanthin on oxidative stress injury induced by hydrogen peroxide (H 2O 2) in lens epithelial cells and its possible mechanism. Methods:The HLEB-3 cells were cultured with different concentrations (0, 50, 100, 200, 500, 750 μmol/L) of H 2O 2.The cell inhibition rate was detected by the methyl thiazolyl tetrazolium (MTT) method, and the 50%inhibiting concentration (IC50) was calculated.HLEB-3 cells were cultured with different concentrations (0, 5, 10, 20, 50 μmol/L) of astaxanthin.The cell survival rate was detected by the MTT method.HLEB-3 cells were divided into four groups for 24-hour culture, namely normal control group cultured with complete medium, oxidative stress group cultured with 250 μmol/L H 2O 2, 10 μmol/L astaxanthin group cultured with 10 μmol/L astaxanthin and 250 μmol/L H 2O 2, and 20 μmol/L astaxanthin group cultured with 20 μmol/L astaxanthin and 250 μmol/L H 2O 2.The cell apoptosis rate was determined by flow cytometry.The nitric oxide (NO) concentration, superoxide dismutase (SOD) activity, glutathione (GSH) activity and malondialdehyde (MDA) content were detected by ELISA.The protein expressions of nuclear factor erythroid-2 related factor 2 (Nrf2) in nuclei, cytoplasmic Nrf2, heme oxygenase-1 (HO-1) and NAD (P) H, quinine oxidoreductase 1 (NQO1) were detected by Western bolt.The cells were divided into four groups, namely normal control-small interfering RNA (NC-siRNA) group, Nrf2-siRNA group, NC-siRNA+ astaxanthin group and Nrf2-siRNA+ astaxanthin group.The cells were transfected with NC-siRNA or Nrf2-siRNA accordingly.The cells were co-cultured for 24 hours with 0/10 μmol/L astaxanthin and 250 μmol/L H 2O 2 24 hours after transfection, respectively.The cell apoptosis rate was determined by flow cytometry.The NO concentration, SOD activity, GSH activity and MDA content were detected by ELISA. Results:With the increase of H 2O 2 concentration, the inhibition rate of HLEB-3 cells increased.There were significant differences in the inhibition rate of HLEB-3 cells treated with different concentrations of H 2O 2 ( F=12.358, P<0.05). The IC50 value of H 2O 2 on HLEB-3 cells was 264.20 μmol/L.The survival rates of HLEB-3 cells treated with 0, 5, 10, 20 and 50 μmol/L astaxanthin were (100.00±0.00)%, (102.20±1.34)%, (109.50±3.60)%, (115.40±4.13)%, (93.60±2.59)%, respectively.Then 10 μmol/L and 20 μmol/L were chosen as the experimental dose.The cell apoptosis rate of oxidative stress group was (38.50±2.38)%, which was higher than (9.20±0.24)% of normal control group, with a statistically significant difference ( P<0.05). The cell apoptosis rate of 10 μmol/L astaxanthin group was (27.60±4.33)%, which was lower than (38.50±2.38)% of oxidative stress group, but higher than (14.90±1.23)% of 20 μmol/L astaxanthin group and (9.20±0.24)% of normal control group, showing statistically significant differences (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in oxidative stress group than in normal control group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and the differences were statistically significant (all at P<0.05). The NO and MDA contents were higher and the SOD and GSH concentrations were lower in 10 μmol/L astaxanthin group than in normal control group and 20 μmol/L astaxanthin groups, and the differences were statistically significant (all at P<0.05). There were significant differences in the relative expression levels of nuclear Nrf2, cytoplasmic Nrf2, HO-1 and NQO1 proteins among normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group ( F=43.512, 20.381, 31.014, 23.435; all at P<0.001). The relative expression of nuclear Nrf2 protein gradually decreased, and the relative expression of nuclear Nrf2, HO-1 and NQO1 proteins increased gradually in normal control group, oxidative stress group, 10 μmol/L astaxanthin group and 20 μmol/L astaxanthin group, and there were significant differences when compared in pairs (all at P<0.05). The apoptosis rates of Nrf2-siRNA group and Nrf2-siRNA+ astaxanthin group were higher than those of NC-siRNA group and NC-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). The cell apoptosis rate was higher in NC-siRNA group than in NC-siRNA+ astaxanthin group, showing a statistically significant difference ( P<0.05). There was no significant difference in the apoptosis rate between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group ( P>0.05). The NO and MDA concentrations were higher and the SOD and GSH activities were lower in Nrf2-siRNA group than in the NC-siRNA group, with statistically significant differences (all at P<0.05). The NO and MDA concentrations were lower and the SOD and GSH activities were higher in NC-siRNA+ astaxanthin group than in NC-siRNA group and Nrf2-siRNA+ astaxanthin group, and the differences were statistically significant (all at P<0.05). There was no significant difference in NO and MDA concentrations or the SOD and GSH activities between Nrf2-siRNA+ astaxanthin group and Nrf2-siRNA group (all at P>0.05). Conclusions:Astaxanthin enhances the resistance of lens epithelial cells to H 2O 2-induced oxidative stress damage, which may be achieved by activating the Nrf2-related signaling pathway.

Plumbagin Induces Ferroptosis Through Nrf-2/Keap1 Signaling Pathway in Bladder Cancer Cells / 中国实验方剂学杂志

ObjectiveTo explore the mechanism of plumbagin as a novel ferroptosis inducer in bladder cancer inhibition. MethodBladder cancer T24 cells were used in this study. The effect of different concentrations of plumbagin （0.1， 1， 2， 3， 6， 12， 24， 48 μmol·L-1） on the viability of T24 cells was detected by cell counting kit-8 （CCK-8）. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the apoptosis of T24 cells was detected by annexin V-fluorescein isothiocyanate （Annexin V FITC）/PI apoptosis kit. Different inhibitors （ferroptosis inhibitor Fer-1， apoptosis inhibitor VAD， and necroptosis inhibitor Nec-1） were used in combination with plumbagin （6 μmol·L-1）. Reactive oxygen species （ROS） fluorescent probe （DCFH-DA）， malonaldehyde （MDA）， and glutathione （GSH） kits were used to detect the effects of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the level of ROS and the content of MDA and GSH in T24 cells， respectively. The effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on peroxide levels in T24 cells was detected by C11-BODIPY fluorescent probe. Western blot was used to detect the effect of different concentrations of plumbagin （1.5， 3， 6 μmol·L-1） on the protein expression of solute carrier family 7 member 11 （SLC7A11）， glutathione peroxidase 4 （GPX4）， nuclear factor E2-related factor-2 （Nrf-2）， and Kelch-like ECH-associated protein 1 （Keap1）. ResultCompared with the blank group， plumbagin could inhibit the activity of T24 cells （P<0.05） with IC50 of 3.52 μmol·L-1. At the concentrations of 1.5， 3， 6 μmol·L-1， plumbagin significantly promoted the apoptosis of T24 cells （P<0.05） as compared with the blank group. Compared with the plumbagin group at 6 μmol·L-1， the ferroptosis inhibitor and apoptosis inhibitor groups could reverse the inhibitory effect of 6 μmol·L-1 plumbagin on the proliferation of T24 cells （P<0.05）. Compared with the blank group， the plumbagin groups at 1.5， 3， 6 μmol·L-1 showed increased content of ROS， MDA， and lipid peroxides in T24 cells， decreased GSH level， and reduced SLC7A11， GPX4， and Nrf-2/Keap1 （P<0.05）. Conclusionplumbagin can induce ferroptosis， and its mechanism is related to the Nrf-2/Keap1 signaling pathway.

Mechanisms mediating the inhibitory effects of quercetin against phthalates-induced testicular oxidative damage in rats / 南方医科大学学报

OBJECTIVE@#To explore the mechanism underlying the inhibitory effect of quercetin against testicular oxidative damage induced by a mixture of 3 commonly used phthalates (MPEs) in rats.@*METHODS@#Forty male Sprague-Dawley rats were randomly divided into control group, MPEs exposure group, and MPEs with low-, median- and high-dose quercetin treatment groups. For MPEs exposure, the rats were subjected to intragastric administration of MPEs at the daily dose of 900 mg/kg for 30 consecutive days; Quercetin treatments were administered in the same manner at the daily dose of 10, 30, and 90 mg/kg. After the treatments, serum levels of testosterone, luteinizing hormone (LH), follicle stimulating hormone (FSH), and testicular malondialdeyhde (MDA), catalase (CAT) and superoxide dismutase (SOD) were detected, and testicular pathologies of the rats were observed with HE staining. The expressions of nuclear factor-E2-related factor 2 (Nrf2), Kelch-like ECH2 associated protein 1 (Keap1) and heme oxygenase 1 (HO-1) in the testis were detected using immunofluorescence assay and Western blotting.@*RESULTS@#Compared with the control group, the rats with MPEs exposure showed significant reductions of the anogenital distance, weight of the testis and epididymis, and the coefficients of the testis and epididymis with lowered serum testosterone, LH and FSH levels (P < 0.05). Testicular histological examination revealed atrophy of the seminiferous tubules, spermatogenic arrest, and hyperplasia of the Leydig cells in MPEs-exposed rats. MPEs exposure also caused significant increments of testicular Nrf2, MDA, SOD, CAT and HO-1 expressions and lowered testicular Keap1 expression (P < 0.05). Treatment with quercetin at the median and high doses significantly ameliorated the pathological changes induced by MPEs exposure (P < 0.05).@*CONCLUSION@#Quercetin treatment inhibits MPEs-induced oxidative testicular damage in rats possibly by direct scavenging of free radicals to lower testicular oxidative stress and restore the regulation of the Nrf2 signaling pathway.

Effect and mechanism of Bajitianwan on preventing D-galactose-induced osteoblast bone loss / 药学实践杂志

Objective To explore the effect and mechanism of Bajitianwan on preventing D-galactose (D-gal)-induced osteoblast bone loss. Methods Osteoblasts isolated from 24 h old Wistar rats were injured by D-gal and intervened with Bajitianwan extract. The osteoblastic proliferation and differentiation were determined by MTT and alkaline phosphatase (ALP), respectively. The cell reactive oxygen species (ROS) levels were detected by DCFH-DA fluorescent probes. The expression of cellular oxidation-related protein nuclear factor erythroid 2-related factor 2 (Nrf2), phosphorylated protein kinase B (p-AKT), protein kinase B (AKT), heme oxygenase-1 (HO-1), and NADPH quinone oxidoreductase 1 (NQO1) were detected by Western blotting. The intranuclear expression of Nrf2 protein was measured by immunofluorescence. Results Bajitianwan extract had significantly increased the osteoblastic proliferation and differentiation, and significantly reduced the intracellular ROS level. Bajitianwan extract had activated the PI3K/AKT pathway via activating the phosphorylation of AKT in osteoblasts, and promoted NQO1 and HO-1 expression. In addition, Bajitianwan had significantly promoted the expression of Nrf2 in the nucleus of osteoblasts, activating Nrf2 signaling pathway, and further promoted bone formation. Conclusion This study confirmed that Bajitianwan could prevent D-gal injured osteoblastic bone loss for the first time. The mechanism might be related to the regulation of oxidative stress associated PI3K/AKT and Nrf2 signaling pathway.

Effects of obacunone on renal interstitial fibrosis and ferroptosis in unilateral ureteral obstruction model mice / 中国药房

OBJECTVE To study the improvement effects of obacunone on renal interstitial fibrosis （RIF） in unilateral ureteral obstruction （UUO） model mice， and to investigate its mechanism based on ferroptosis mediated by nuclear factor erythroid 2- related factor 2（Nrf2）/glutathione peroxidase 4 （GPx4） signaling pathway. METHODS Thirty mice were randomly divided into sham operation group， model group， irbesartan group （positive control， 20 mg/kg）， obacunone low-dose and high-dose groups （10， 40 mg/kg）， with 6 mice in each group. Except for sham operation group， UUO model was established by ligation of unilateral ureter in other groups. After operation， administration groups were given intraperitoneal injection of relevant medicine， and sham operation group and model group were given intraperitoneal injection of constant volume of normal saline， once a day， for 7 consecutive days. The levels of creatinine （Cr） and blood urea nitrogen （BUN）， the content of malondialdehyde （MDA） and the activities of total superoxide dismutase （T-SOD） in serum and the concentration of Fe2+ in renal tissue were all detected. HE staining and Masson staining were performed to observe the morphology and the fibrosis of renal tissues. Immunohisto- chemical staining was used to determine expressions of the fibronectin （Fn）， α-smooth muscle actin （α-SMA）， GPx4 964083717@qq.com and Nrf2 in renal tissue. Western blot and real-time quantitative polymerase chain reaction （RT-qPCR） were used E-mail：834300205@qq.com to detect the protein and mRNA levels of Fn， α-SMA， Nrf2， GPx4 and SLC7A11 in the renal tissues. RESULTS Compared with sham operation group， serum levels of Cr and BUN， the concentration of Fe2+ in renal tissue， the protein and mRNA levels of Fn and α-SMA in model group were increased significantly （P＜0.05）， while the activity of T-SOD in serum， protein and mRNA expressions of Nrf2， GPx4， SLC7A11 in kidney tissue were significantly decreased （P＜0.05）； in the kidney tissue， the renal tubules were dilated， the collagen deposition was obvious， the fibrous bands were thicker and darker， and the renal interstitial inflammatory cells infiltrated significantly. After intervened with obacunone， the levels of above indexes （except for mRNA expression of SLC7A11 in obacunone low-dose group） in serum and renal tissue were reversed significantly （P＜0.05）， and pathological damage and collagen deposition of kidney tissue were alleviated. CONCLUSIONS Obacunone can improve renal interstitial fibrosis of UUO model mice， the mechanism of which may be associated with activating the Nrf2/GPx4 pathway and then inhibiting ferroptosis to relieve RIF in UUO model mice.

Neuroprotection of Natural Products Based on Keap1/Nrf2/ARE Signaling Pathway： A Review / 中国实验方剂学杂志

The pathological manifestations of neurodegenerative diseases， such as Alzheimer's disease， Parkinson's disease， and multiple sclerosis， are abnormal protein aggregation and accumulation， microglia activation， and mitochondrial dysfunction， which eventually lead to the gradual loss of neuronal structure or function and deteriorate over time. These pathological processes are related to the production of reactive oxygen species （ROS）， which can cause oxidative stress and damage proteins， lipids， and DNA， leading to cell and tissue injuries. The Kelch-like ECH-associated protein 1 （Keap1）/nuclear factor E2-related factor 2 （Nrf2）/antioxidant response element （ARE） signaling pathway is the main mechanism to maintain the redox balance of the body and defend against oxidative stress injury. Nrf2 activates the expression of a series of antioxidant genes related to ARE through the dissociation of Keap1 and nuclear transfer in the cytoplasm to protect the body from oxidative damage. Therefore， the discovery and study of the Keap1/Nrf2/ARE signaling pathway activator is of great significance for the prevention and treatment of neurodegenerative diseases. Because of the remarkable biological activity and slight side effects， natural products are a treasure trove for new drug research and development. Studies have shown that a variety of natural products can activate the Keap1/Nrf2/ARE signaling pathway and play a neuroprotective role. According to the structural characteristics， natural products can be divided into flavonoids， terpenoids， volatile oils， polyphenols， and phenylpropanoids. This study summarized the underlying mechanism of the Keap1/Nrf2/ARE signaling pathway in regulating diseases and reviewed the research progress on natural products based on this signaling pathway in neuroprotection to provide references for the development of clinical drugs for the prevention and treatment of neurodegenerative diseases.

Anti-oxidative Stress Effect and Mechanism of Huangqintang on Caco-2 Cells Through Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo verify the anti-oxidative stress effect of Huangqintang based on the nuclear factor E2-related factor 2 （Nrf2） signaling pathway by using Caco-2 cells as a carrier and RNA interference （RNAi） technology with in vitro experiments. MethodThe Caco-2 cells in the logarithmic growth phase were transfected with siRNA to construct siRNA Caco-2 cells. After normal Caco-2 cells and siRNA Caco-2 cells were incubated with Huangqintang of different doses， RNA and protein were extracted. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot were used to detect the mRNA and protein expression of heme oxygenase-1 （HO-1）， NAD（P）H quinone oxidoreductase 1 （NQO1）， glutathione S-transferase （GST）， Kelch-like ECH-associated protein 1 （Keap1）， and Nrf2. Meanwhile， the activities of superoxide dismutase （SOD） and GSH-Px， as well as the expression levels of malondialdehyde （MDA） and reactive oxygen species （ROS）， were detected by the colorimetric method and the probe method. ResultCompared with the results in the normal group， only the 400 mg·L-1 Huangqintang group and the sulforaphane （SFN） group could reduce the content of ROS and MDA in Caco-2 cells （P<0.01）， while the activities of SOD and GSH-Px in the cells of the Huangqintang groups and the SFN group showed an upward trend. Furthermore， there were significant differences in the 400 mg·L-1 Huangqintang group/the SFN group and the normal group （P<0.01）. Meanwhile， the protein and mRNA expression levels of HO-1， GST， Keap1， NQO1， and Nrf2 showed an upward trend in all groups （P<0.05， P<0.01）. After transfection， compared with the normal group， the model group showed increased content of MDA and ROS， blunted activities of GSH-Px and SOD， and reduced protein and mRNA expression of HO-1， GST， Keap1， and NQO1 （P<0.05， P<0.01）. After drug incubation， compared with the model group， the SFN group showed potentiated SOD activity， and the SFN group and the Huangqintang groups showed enhanced GSH-Px activity （P<0.01）. Moreover， the activities of SOD and GSH-Px in the 400 and 200 mg·L-1 Huangqintang groups and the SFN group showed an upward trend （P<0.01）， and the content of MDA in the 400 mg·L-1 Huangqintang group and the SFN group showed a downward trend. ROS decreased in all groups with drug intervention （P<0.01）， and the protein and mRNA expression of HO-1， GST， Keap1， NQO1， and Nrf2 increased to varying degrees （P<0.05， P<0.01）. ConclusionHuangqintang can play an anti-oxidative stress role by regulating the Nrf2 pathway.

Effect of Shenling Baizhusan on Alcoholic Liver Injury in Rats by Regulating Ferroptosis Based on Nrf2 Signaling Pathway / 中国实验方剂学杂志

ObjectiveTo observe the effect of Shenling Baizhusan on the intervention of the nuclear factor erythroid 2-related factor 2 （Nrf2） signaling pathway by regulating ferroptosis in rats with alcoholic liver injury. MethodForty SD rats were randomly divided into model group， polyene phosphatidylcholine group， and high， medium， and low-dose Shenling Baizhusan groups， with 8 rats in each group. Another 8 SD rats were taken as blank group. The model group， polyene phosphatidylcholine group， high， medium， and low-dose Shenling Baizhusan groups were given 10 mL·kg-1 liquor by gavage for modeling， and the blank group was given equal volume of distilled water by gavage. After 4 h of daily alcoholic administration， 143.64 mg·kg-1 of polyene phosphatidylcholine group was given to the polyene phosphatidylcholine group， 15， 7.5， 3.75 mg·kg-1 of Shenling Baizhusan were given to Shenling Baizhusan high， medium， and low-dose groups， respectively， and the blank group and the model group were given equal volume of distilled water. The gavage lasted for 6 weeks. The levels of alanine aminotransferase （ALT）， aspartate aminotransferase （AST）， glutamyl transpeptidase （GGT）， total cholesterol （TC）， and triglyceride （TG） were detected by automatic biochemical analyzer. The levels of tumor necrosis factor-α （TNF-α） and interleukin-β （IL-β） were detected by the enzyme-linked immunosorbent assay （ELISA）. The levels of lipopolysaccharide （LPS）， malondialdehyde （MDA）， superoxide dismutase （SOD）， glutathione （GSH）， and Fe+ were detected by biochemical assay. The pathological changes in the liver were observed by hematoxylin-eosin （HE） staining and oil red O staining. The mRNA expression levels of Nrf2， heme oxygenase-1 （HO-1）， glutathione peroxidase 4 （GPX4）， ferritin heavy polypeptide 1 （FTH1）， and nuclear factor-κB （NF-κB） were detected by Real-time polymerase chain reaction （Real-time PCR）. The protein expression levels of Nrf2， HO-1， GPX4， FTH1， p65， and phosphorylation （p）-p65 were detected by Western blot. ResultAs compared with the blank group， the levels of liver function （ALT， AST， and GGT） and blood lipids （TC and TG） in the model group were significantly increased （P<0.05）. The liver showed obvious steatosis， with a large number of fat deposition， the oxidative stress and inflammatory factors were significantly increased （P<0.05）， and the level of Fe+ was significantly increased in model group （P<0.05）. The protein expression levels of Nrf2， HO-1， GPX4， and FTH1 was significantly down-regulated （P<0.05）， and those of p65 and p-p65 was significantly up-regulated in the model group （P<0.05）. The mRNA expression levels of Nrf2， HO-1， GPX4， and FTH1 were significantly down-regulated （P<0.05）， and the mRNA expression level of NF-κB was significantly up-regulated （P<0.05）. As compared with the model group， the levels of liver function （ALT， AST， and GGT） and blood lipids （TC and TG） in the high-dose and medium-dose Shenling Baizhusan groups were significantly decreased （P<0.05）， liver steatosis was significantly improved， fat deposition was significantly reduced， oxidative stress and inflammatory factors were significantly decreased （P<0.05 ）， and Fe+ level was significantly decreased （P<0.05）. In the high-dose and medium-dose Shenling Baizhusan， the protein expression levels of Nrf2， HO-1， GPX4， and FTH1 were significantly up-regulated （P<0.05）， and those of p65， p-p65 were significantly down-regulated （P<0.05）. The mRNA expression levels of Nrf2， HO-1， GPX4， and FTH1 were significantly up-regulated （P<0.05）， and the mRNA expression level of NF-κB was significantly down-regulated （P<0.05）. ConclusionShenling Baizhusan can effectively reduce liver injury in rats with ALD， regulate steatosis and fat deposition， and play an antioxidant and anti-inflammatory role in the liver. Its mechanism may be related to the inhibition of ferroptosis in hepatocytes by up-regulating the Nrf2 signaling pathway to improve oxidative stress

Antidepressant mechanism of Shenling Kaixin Granules based on BDNF/TrkB/CREB pathway / 中国中药杂志

To investigate the antidepressant mechanism of Shenling Kaixin Granules(SLKX) in treating chronic unpredictable mild stress(CUMS) model rats. Ninety male SD rats were randomly divided into control group, model group, Shugan Jieyu Capsules(110 mg·kg~(-1)) group and SLKX low-(90 mg·kg~(-1)), medium-(180 mg·kg~(-1)), and high-dose(360 mg·kg~(-1)) groups. Depression rat model was replicated by CUMS method. After treatment, the behavioral changes of rats were evaluated by sugar preference, open field, elevated cross maze and forced swimming experiments. The contents of interleukin 1 beta(IL-1β), tumor necrosis factor α(TNF-α), brain-derived neurotrophic factor(BDNF) and 5-hydroxytryptamine(5-HT) in serum were determined by enzyme linked immunosorbent assay(ELISA), and the activities of superoxide dismutase(SOD) and catalase(CAT) in hippocampal CA1 region were also detected. Pathological changes in hippocampal CA1 region were detected by hematoxylin-eosin(HE) staining, and Western blot was used to determine the expression of nerve growth factor(NGF), BDNF, phospho-tyrosine kinase receptor(p-TrkB)/TrkB, phospho-cAMP-response element binding protein(p-CREB)/CREB, nuclear factor E2 related factor 2(Nrf2), heme oxygenase 1(HO-1), B-cell lymphoma-2(Bcl-2)/Bcl-2 associated X protein(Bax) and caspase-3 in hippocampal CA1 region. RESULTS:: showed that compared with the control group, the model group had decreased sugar preference, reduced number of entries and time spent in the center of open field and shortened total distance of movement, reduced number of entries and proportion of time spent in open arm, and increased number and time of immobility in forced swimming experiment. Additionally, the serum contents of IL-1β and TNF-α and the expression of caspase-3 were higher, while the contents of BDNF and 5-HT, the activities of SOD and CAT in hippocampal CA1 region, the expressions of NGF, BDNF, p-TrkB/TrkB, p-CREB/CREB, HO-1 and Bcl-2/Bax, and the Nrf2 nuclear translocation were lower in model group than in control group. Compared with the conditions in model group, the sugar preference, the number of entries and time spent in the center of open, total distance of movement, and the number of entries and proportion of time spent in open arm in treatment groups were increased while the number and time of immobility in forced swimming experiment were decreased; the serum contents of IL-1β and TNF-α and the expression of caspase-3 were down regulated, while the contents of BDNF and 5-HT, the activities of SOD and CAT in hippocampal CA1 region, the expressions of NGF, BDNF, p-TrkB/TrkB, p-CREB/CREB, HO-1, Bcl-2/Bax, and Nrf2 nuclear translocation were enhanced. In conclusion, SLKX might regulate the Nrf2 nucleus translocation by activating BDNF/TrkB/CREB pathway, lower oxidative stress damage in hippocampus, inhibit caspase-3 activity, and reduce apoptosis of hippocampal nerve cells, thereby playing an antidepressant role.

Leonurine inhibits ferroptosis in renal tubular epithelial cells by activating p62/Nrf2/HO-1 signaling pathway / 中国中药杂志

To investigate the protective effect and the potential mechanism of leonurine(Leo) against erastin-induced ferroptosis in human renal tubular epithelial cells(HK-2 cells), an in vitro erastin-induced ferroptosis model was constructed to detect the cell viability as well as the expressions of ferroptosis-related indexes and signaling pathway-related proteins. HK-2 cells were cultured in vitro, and the effects of Leo on the viability of HK-2 cells at 10, 20, 40, 60, 80 and 100 μmol·L~(-1) were examined by CCK-8 assay to determine the safe dose range of Leo administration. A ferroptosis cell model was induced by erastin, a common ferroptosis inducer, and the appropriate concentrations were screened. CCK-8 assay was used to detect the effects of Leo(20, 40, 80 μmol·L~(-1)) and positive drug ferrostatin-1(Fer-1, 1, 2 μmol·L~(-1)) on the viability of ferroptosis model cells, and the changes of cell morphology were observed by phase contrast microscopy. Then, the optimal concentration of Leo was obtained by Western blot for nuclear factor erythroid 2-related factor 2(Nrf2) activation, and transmission electron microscope was further used to detect the characteristic microscopic morphological changes during ferroptosis. Flow cytometry was performed to detect reactive oxygen species(ROS), and the level of glutathione(GSH) was measured using a GSH assay kit. The expressions of glutathione peroxidase 4(GPX4), p62, and heme oxygenase 1(HO-1) in each group were quantified by Western blot. RESULTS:: showed that Leo had no side effects on the viability of normal HK-2 cells in the concentration range of 10-100 μmol·L~(-1). The viability of HK-2 cells decreased as the concentration of erastin increased, and 5 μmol·L~(-1) erastin significantly induced ferroptosis in the cells. Compared with the model group, Leo dose-dependently increased cell via-bility and improved cell morphology, and 80 μmol·L~(-1) Leo promoted the translocation of Nrf2 from the cytoplasm to the nucleus. Further studies revealed that Leo remarkably alleviated the characteristic microstructural damage of ferroptosis cells caused by erastin, inhibited the release of intracellular ROS, elevated GSH and GPX4, promoted the nuclear translocation of Nrf2, and significantly upregulated the expression of p62 and HO-1 proteins. In conclusion, Leo exerted a protective effect on erastin-induced ferroptosis in HK-2 cells, which might be associated with its anti-oxidative stress by activating p62/Nrf2/HO-1 signaling pathway.

Eucommia lignans alleviate the progression of diabetic nephropathy through mediating the AR/Nrf2/HO-1/AMPK axis in vivo and in vitro / 中国天然药物

Lignans derived from Eucommia ulmoides Oliver (Eucommia lignans) inhibit the progression of inflammatory diseases, while their effect on the progression of diabetic nephropathy (DN) remained unclear. This work was designed to assess the function of Eucommia lignans in DN. The major constituents of Eucommia lignans were analyzed by UPLC-Q-TOF-MS/MS. The binding between Eucommia lignans and aldose reductase (AR) was predicted by molecular docking. Eucommia lignans (200, 100, and 50 mg·kg-1) were used in model animals to evaluate their renal function changes. Rat glomerular mesangial cells (HBZY-1) were transfected with sh-AR, sh-AMPK, and oe-AR in the presence of high glucose (HG) or HG combined with Eucommia lignans to evaluate whether Eucommia lignans affected HG-induced cell injury and mitochondrial dysfunction through the AR/Nrf2/HO-1/AMPK axis. Eucommia lignans significantly attenuated the progression of DN in vivo. Eucommia lignans notably reversed HG-induced upregulation of inflammatory cytokines and mitochondrial injury, while downregulating the levels of Cyto c, caspase 9, AR, and NOX4 in HBZY-1 cells. In contrast, HG-induced downregulation of Nrf2, HO-1 and p-AMPKα levels were abolished by Eucommia lignans. Meanwhile, knockdown of AR exerted similar therapeutic effect of Eucommia lignans on DN progression, and AR overexpression reversed the effect of Eucommia lignans. Eucommia lignans alleviated renal injury through the AR/Nrf2/HO-1/AMPK axis. Thus, these findings might provide evidence for the use of Eucommia lignans in treating DN.

Engineered Bacillus subtilis alleviates intestinal oxidative injury through Nrf2-Keap1 pathway in enterotoxigenic Escherichia coli (ETEC) K88-infected piglet / 浙江大学学报（英文版）（B辑：生物医学和生物技术）

Engineered probiotics can serve as therapeutics based on their ability of produce recombinant immune-stimulating properties. In this study, we built the recombinant Bacillus subtilis WB800 expressing antimicrobial peptide KR32 (WB800-KR32) using genetic engineering methods and investigated its protective effects of nuclear factor-E2-related factor 2 (Nrf2)‍-Kelch-like ECH-associated protein 1 (Keap1) pathway activation in intestinal oxidative disturbance induced by enterotoxigenic Escherichia coli (ETEC) K88 in weaned piglets. Twenty-eight weaned piglets were randomly distributed into four treatment groups with seven replicates fed with a basal diet. The feed of the control group (CON) was infused with normal sterilized saline; meanwhile, the ETEC, ETEC+WB800, and ETEC+WB800-KR32 groups were orally administered normal sterilized saline, 5×1010 CFU (CFU: colony forming units) WB800, and 5×1010 CFU WB800-KR32, respectively, on Days 1‍‒‍14 and all infused with ETEC K88 1×1010 CFU on Days 15‍‒‍17. The results showed that pretreatment with WB800-KR32 attenuated ETEC-induced intestinal disturbance, improved the mucosal activity of antioxidant enzyme (catalase (CAT), superoxide dismutase (SOD), and glutathione peroxidase (GPx)) and decreased the content of malondialdehyde (MDA). More importantly, WB800-KR32 downregulated genes involved in antioxidant defense (GPx and SOD1). Interestingly, WB800-KR32 upregulated the protein expression of Nrf2 and downregulated the protein expression of Keap1 in the ileum. WB800-KR32 markedly changed the richness estimators (Ace and Chao) of gut microbiota and increased the abundance of Eubacterium_rectale_ATCC_33656 in the feces. The results suggested that WB800-KR32 may alleviate ETEC-induced intestinal oxidative injury through the Nrf2-Keap1 pathway, providing a new perspective for WB800-KR32 as potential therapeutics to regulate intestinal oxidative disturbance in ETEC K88 infection.