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ObjectiveBased on the nuclear factor erythroid 2 related factor 2 （Nrf2）/heme oxygenase-1 （HO-1） signaling pathway， this paper explores the effect of Sinisan （SNS） on liver oxidative stress injury in cholestatic hepatitis rats and its mechanism. MethodThirty 6-week-old male SD rats were randomly divided into a control group， model group， low and high dose groups of SNS （2.5 and 5 g·kg-1） and ursodeoxycholic acid group （UDCA， 63 mg·kg-1）， with six rats in each group. Rats were administrated for seven consecutive days. On the 5th day， the control group was given olive oil of 10 mL·kg-1， and the other groups were given alpha-naphthalene isothiocyanate （ANIT） of 80 mg·kg-1. The serum biochemical indicator levels of cholestasis and the content of antioxidant factors in rat liver were detected by enzyme-linked immunosorbent assay （ELISA）. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in liver tissue. The relative mRNA and protein expressions of Nrf2， HO-1， and quinone oxidoreductase 1 （NQO1） in liver tissue were detected by real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） and Western blot. ResultCompared with the control group， the model group showed a significant increase in the serum biochemical indicator levels of cholestasis and the content of antioxidant factors in liver tissue （P<0.01）. There were obvious pathological changes in the model group such as the disordered arrangement of hepatocytes， obvious congestion and necrosis in the portal area， infiltration of inflammatory cells， and destruction of the interlobular bile duct. The relative mRNA and protein expressions of Nrf2， HO-1， and NQO1 in liver tissue were significantly down-regulated in the model group （P<0.05， P<0.01）. Compared with the model group， the groups of SNS showed a significant decrease in the serum biochemical indicator levels of cholestasis and the content of antioxidant factors in liver tissue （P<0.01）， and the pathological liver injury was obviously improved. The necrotic area was reduced， and the infiltration of inflammatory cells was decreased. In addition， there was a small amount of extravasated blood in the interlobular vein. The relative mRNA and protein expressions of Nrf2， HO-1， and NQO1 in liver tissue were significantly up-regulated （P<0.05， P<0.01）. ConclusionSNS can significantly improve liver injury in cholestatic hepatitis rats， and its mechanism may be related to the inhibition of oxidative stress response mediated by the Nrf2/HO-1 signaling pathway.
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Objective To investigate the role of heme oxygenase-1(HO-1)on HBV replication and the antiviral effect of HO-1 combined with α-interferon(IFN-α).Methods HepG2.2.15 cells and HBV1.3-transfected HepG2 cells(HepG2-HBV1.3)were used as HBV replicating cell models;Hemin treated HepG2.2.15 and HepG2-HBV1.3 cells,to induce the expression of HO-1 molecules.CCK-8 method was used to assess the toxic effects of Hemin on HepG2 and HepG2.2.15;chemiluminescence method was used to analyze HBsAg and HBeAg in the supernatants of Hemin-treated group and si-HO-1 and other experimental groups;RT-qPCR was used to ana-lyze HO-1,IFN-β and HBV-DNA;Western blot was used to analyze the expression of IRF-3 and the expression of related molecules in the JAK/STAT signaling pathway;Hemin combined with IFN-α treated HepG2.2.15 to moni-tor whether HO-1 had synergistic IFN-α antiviral effect.Results Hemin dose-dependently induced HO-1,and HO-1 was induced to exert a significant anti-HBV effect,while the expression of IFN-β,IRF-3,and IRF-9 and MxA,downstream molecules of the JAK/STAT signaling pathway,were all increased.Silencing HO-1 expression reversed the antiviral effect in the Hemin-induced group,and at the same time,type Ⅰ interferon IFN-β showed low expression,and the expression of IRF-9 and MxA in the JAK/STAT signaling pathway was inhibited as well.He-min combined with IFN-α exerted stronger antiviral effects.Conclusion HO-1 can exert an anti-HBV effect,which may be due to increased phosphorylation of IRF-3 to induce type Ⅰ interferon expression and thus activate the JAK/STAT signaling pathway to exert an antiviral effect;HO-1 can synergize with IFN-α to exert an antiviral effect.
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Objective:To discuss the protective effect of gingerone on the hippocampal neuron HT22 cells after oxygen-glucose deprivation/reoxygenation(OGD/R),and to clarify the related mechanism.Methods:The HT22 cells were cultured,and the OGD/R cell injury model was established by setting the gradient of OGD/R time.The HT22 cells were divided into control group,OGD/R group,OGD/R+ 1 μmol·L-1 gingerone group,OGD/R + 10 μmol·L-1 gingerone group,OGD/R+100 μmol·L-1 gingerone group,and OGD/R+0.2%dimethyl sulfoxide(DMSO)group.The viability of the cells in various groups was detected by CCK-8 assay;the survival rates of the cells in various groups were calculated to determine the optimal drug concentration of gingerone.The cells were divided into control,OGD/R group,OGD/R+ gingerone,and OGD/R+gingerone+nuclear factor erythroid-2-related factor 2(Nrf2)inhibitor(ML385)groups.The cells in OGD/R + gingerone group were treated with gingerone for 4 h before OGD treatment for 8 h followed by reoxygenation for 8 h,and the cells in OGD/R+gingerone+ ML385 group were treated with 10 μmol·L-1 ML385 for 6 h before gingerone treatment.The viability of the cells in various groups was detected by CCK-8 assay;the expression levels of Nrf2,heme oxygenase-1(HO-1),B-cell lymphoma-2(Bcl-2),and Bcl-2-associated X protein(Bax)proteins in the cells in various groups were detected by Western blotting method;the activity of superoxide dismutase(SOD)and the level of malondialdehyde(MDA)in the cell culture supernatant in various groups were detected by enzyme-linked immunosorbent assay(ELISA)method.Results:Compared with control group,the survival rate of the HT22 cells was below 50%after treated with OGD for 8 h and reoxygenation for 8 h,so the HT22 cell OGD/R model was established by treated with OGD for 8 h and reoxygenation for 8 h.Compared with OGD/R group,the survival rates of the cells in OGD/R+different doses of gingerone groups were increased to various extents,and the survival rate of the cells in OGD/R+ 100 μmol·L-1 gingerone group was significantly increased(P<0.01);so 100 μmol·L-1 gingerone was used for the subsequent experiment.Compared with control group,the viability of the cells in OGD/R group was significantly decreased(P<0.01),and the expression levels of Nrf2,HO-1,and Bax proteins in the cells were significantly increased(P<0.01),while the expression level of Bcl-2 protein in the cells was significantly decreased(P<0.05),and the SOD activity in the cell culture supernatant was significantly decreased(P<0.01),and the level of MDA was significantly increased(P<0.01);compared with OGD/R group,the viability of the cells in OGD/R + gingerone group was significantly increased(P<0.01),and the expression levels of Nrf2,HO-1,and Bcl-2 proteins in the cells were significantly increased(P<0.05 or P<0.01),while the expression level of Bax protein in the cells was decreased(P<0.05),the SOD activity in the cell culture supernatant was significantly increased(P<0.01),and the level of MDA was significantly decreased(P<0.01);compared with OGD/R + gingerone group,the viability of the cells in OGD/R + gingerone + ML385 group was significantly decreased(P<0.01),and the expression levels of Nrf2,HO-1,and Bcl-2 proteins were significantly decreased(P<0.01),while the expression level of Bax protein in the cells was significantly increased(P<0.01),the SOD activity in the cell culture supernatant was significantly decreased(P<0.01),and the level of MDA was significantly increased(P<0.05).Conclusion:Gingerone alleviates the oxidative stress damage,and thereby plays an inhibiory effect on the apoptosis of the HT22 neurons by activating the Nrf2/HO-1 signaling pathway after OGD/R.
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BACKGROUND:Studies have shown that atorvastatin can up-regulate the expression of heme oxygenase-1 and enhance the anti-inflammation and anti-oxidative damage ability of cells.However,whether atorvastatin can regulate macrophage polarization,inhibit inflammation and reduce cholesterol accumulation by inducing heme oxygenase-1 expression remains unclear. OBJECTIVE:To investigate the effect of atorvastatin on polarization,inflammation and cholesterol content of oxidized low-density lipoprotein stimulated RAW264.7 macrophages by inducing heme oxygenase-1 expression and its related mechanism. METHODS:Firstly,RAW264.7 cells were randomly divided into six groups and incubated with different concentrations of atorvastatin for 24 hours.The expression of heme oxygenase-1 protein and cell activity were detected to explore the optimal dose of atorvastatin for subsequent studies.RAW264.7 cells were randomly divided into control group,atorvastatin group and heme oxygenase-1 inhibition group.Cells were preincubated with pure medium,atorvastatin 20 μmol/L and atorvastatin 20 μmol/L + zinc protoporphyrin IX 10 μmol/L for 24 hours,and then oxidized low-density lipoprotein 50 mg/L was added for 48 hours.The polarization of macrophages was detected by flow cytometry.The secretion of inflammatory factors such as transforming growth factor β,interleukin 10,interleukin 1β,and tumor necrosis factor α was detected by ELISA.The expression levels of heme oxygenase-1,LC3II,LC3I,P62,PPARγ and ABCA1 were detected by western blot assay.The intracellular cholesterol content was measured with the oxidose method and the accumulation degree of intracellular lipid droplets was evaluated by oil red O staining. RESULTS AND CONCLUSION:(1)Atorvastatin could induce the expression of heme oxygenase-1 protein in macrophages in a dose-dependent manner.(2)Oxidized low-density lipoprotein could induce macrophages to polarize towards M1,secrete proinflammatory factors,and increase the accumulation of intracellular cholesterol.(3)Compared with the control group,the heme oxygenase-1 protein expression of macrophages was increased after atorvastatin intervention,and the cells turned to M2-type polarization and mainly secreted anti-inflammatory factors such as transforming growth factor-β and interleukin-10.PPARγ,ABCA1,LC3II/I and other signal molecules reflecting cholesterol efflux and autophagy increased,and the contents of intracellular cholesterol and lipid droplets decreased significantly(P<0.05).(4)The heme oxygenase-1 inhibition group treated with zinc protoporphyrin IX significantly reversed the above changes in the atorvastatin group.(5)The results have shown that atorvastatin may promote the polarization of macrophages stimulated by oxidized low-density lipoprotein to M2 type and inhibit inflammation by up-regulating the expression of heme oxygenase-1 and by up-regulating PPARγ/ABCA1 signaling pathway and enhancing autophagy.Atorvastatin can increase the outflow of intracellular cholesterol and reduce the accumulation of intracellular lipids.
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BACKGROUND:Intervertebral disc degeneration is the basis of spinal degenerative diseases;however,there is no effective treatment. OBJECTIVE:To investigate whether sinomenine can inhibit interleukin-1β-induced apoptosis in nucleus pulposus cells and its molecular mechanism. METHODS:Rat nucleus pulposus cells were cultured in vitro by trypsin combined with type II collagenase digestion,and the cell growth curve was plotted.An appropriate sinomenine concentration was determined using the cell counting kit-8 kit.Nucleus pulposus cells were divided into control group,sinomenine group,interleukin-1β group,sinomenine+interleukin-1β group,zinc protoporphyrin group,zinc protoporphyrin+sinomenine group,zinc protoporphyrin+interleukin-1β group,and sinomenine+zinc protoporphyrin+interleukin-1β group.Proliferative activity,reactive oxygen species content,apoptosis rate,and heme oxygenase-1 expression in nucleus pulposus cells were detected. RESULTS AND CONCLUSION:The rat nucleus pulposus cells cultured in vitro were polygonal,triangular,and short wedge-shaped,and the cell growth showed an"S"curve.The cells grew slowly in the first 3 days of culture,rapidly in 4-6 days,and slowly again in 7-8 days.The cells then entered the"platform stage"where the number of cells no longer increased.The proliferative activity of myeloid cells showed no significant changes when the concentration of sinomenine was≤80 μmol/L(P>0.05).Interleukin-1β significantly reduced the proliferative activity of nucleus pulposus cells,increased the content of reactive oxygen species and led to apoptosis(P<0.01).Sinomenine intervention not only promoted heme oxygenase-1 expression(P<0.05)but also inhibited interleukin-1β-induced decrease in proliferative activity and increase in reactive oxygen species content and apoptosis rate in nucleus pulposus cells(P<0.05).These effects could be reversed by zinc protoporphyrin(P<0.01).
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BACKGROUND:With the aging of the global population,the incidence rate of osteoporosis is also increasing.It is very important to further understand its pathogenesis and propose new therapeutic targets.Recent studies have shown that ferroptosis is closely related to the pathogenesis of some bone diseases,such as inflammatory arthritis,osteoporosis and osteoarthritis. OBJECTIVE:To summarize the previous studies on the mechanism of ferroptosis in osteoporosis,so as to provide new therapeutic ideas and potential therapeutic targets for osteoporosis. METHODS:The first author used the computer to search the documents published from 2000 to 2022 in CNKI,WanFang,VIP,PubMed and Web of Science with the key words of"ferroptosis,osteoporosis,osteoblasts,osteoclasts,iron chelators,reactive oxygen species,nuclear factor erythroid 2-related factor 2,heme oxygenase-1,glutathione peroxidase 4,review"in Chinese and English.A total of 70 articles were finally included according to the inclusion criteria. RESULTS AND CONCLUSION:Ferroptosis is significantly different from necrosis,apoptosis and autophagy.In terms of cell morphology and function,it does not have the morphological characteristics of typical necrosis,nor does it have the characteristics of traditional apoptosis,such as cell contraction,chromatin condensation,the formation of apoptotic bodies and the disintegration of cytoskeleton.Contrary to autophagy,ferroptosis does not form a classical closed bilayer membrane structure(autophagic vacuole).Morphologically,ferroptosis is mainly manifested by obvious contraction of mitochondria,increased membrane density,and reduction or disappearance of mitochondrial cristae,which are different from other cell death modes.Iron overload can destroy bone homeostasis by significantly inhibiting osteogenic differentiation and stimulating osteoclast formation,leading to osteoporosis.Iron overload interferes with the differentiation of stem cells to osteoblasts,leading to a weakened osteoblast function and further imbalance of bone metabolism in the body,which eventually leads to osteoporosis.Stimulated by iron overload,osteoclast bone resorption is enhanced and bone loss exceeds new bone formation.Iron chelators have been proved to have osteoprotective effects by inhibiting osteoclast activity and stimulating osteogenic differentiation of osteoblasts.Its potential mechanism is related to inhibiting osteoclast differentiation and promoting osteoblast differentiation.Antioxidants can prevent reactive oxygen species production and inhibit bone absorption,thus improving bone metabolism and effectively preventing osteoporosis.
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BACKGROUND:Glucocorticoid-induced osteoporosis is a common complication of systemic glucocorticoid therapy,which is mainly characterized by its inhibitory effect on osteoblasts.Eriodictyol inhibits osteoclast differentiation and osteoporosis-induced by ovariectomy.However,it is unclear whether eriodictyol regulates glucocorticoid-induced osteoblasts. OBJECTIVE:To explore whether eriodictyol plays a role in glucocorticoid-induced osteoblast apoptosis and its potential regulatory mechanisms. METHODS:Dexamethasone-pretreated osteoblasts MC3T3-E1 were treated with the different concentrations(0,0.5,1,2.5,5,10 μmol/L)of eriodictyol or 5 μmol/L 3-methyladenine,an autophagy inhibitor,and then transfected with heme oxygenase 1 overexpression vector(pcDNA-HMOX1)and empty vector(pcDNA vector).Cell proliferation and apoptosis were assessed by using cell counting kit-8 assay and flow cytometry,respectively.The activity of caspase-3 was detected with ELISA.Western blot assay was used to detect the protein expression of autophagy-related proteins LC3-Ⅱ/LC3-Ⅰ,p62,Atg5 and Atg12,the expression of apoptotic related proteins Bax and Bcl-2,as well as the protein expression of AMPK and p-AMPK. RESULTS AND CONCLUSION:Low concentrations of eriodictyol were non-toxic to MC3T3-E1 cells and promoted cell proliferation,as well as increased the expression of autophagy related proteins LC3-Ⅱ/LC3-Ⅰ,p62,Atg5 and Atg12,decreased caspase-3 enzyme activity,inhibited Bax protein expression,promoted Bcl-2 protein expression and reduced dexamethasone-induced apoptosis in MC3T3-E1 cells in a dose-dependent manner.Moreover,eriodictyol significantly promoted heme oxygenase 1 expression in osteoblasts,whereas overexpression of heme oxygenase 1 promoted AMPK phosphorylation,activated autophagy,and inhibited dexamethasone-induced osteoblast apoptosis.While 3-methyladenine treatment counteracted the effects of heme oxygenase 1 overexpression on MC3T3-E1 cells.To conclude,low concentration of Eriodictyol is non-toxic to osteoblasts and activates AMPK signaling pathway by upregulating the expression of heme oxygenase 1,thereby promoting autophagy and inhibiting dexamethasone-induced osteoblast apoptosis.Eriodictyol has great potential for the treatment of glucocorticoid-induced osteoporosis.
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AIM:To observe the effect of curcumin on a C57BL/6J mouse liver cancer model induced by N-ni-trosodiethylamine(DEN)combined with carbon tetrachloride(CCl4),and to explore its mechanism.METHODS:Forty young male C57BL/6J mice were intraperitoneally injected with DEN(25 mg/kg)14 d after birth and randomly divided in-to the following 4 groups at the 4th week(10 in each group):model control group and curcumin(100,200 and 400 mg/kg)groups.Ten male mice of the same age were used as normal control group.The mice in model group and curcumin groups were gavaged with 10%CCl4(5 mL/kg)twice a week from the 8th week on.At the same time,the mice in curcumin groups were gavaged with curcumin,and the mice in normal control group were gavaged with the same volume of distilled water once a day for 14 weeks.After administration,the mice were sacrificed,the liver surface was observed,and the number of tumor nodules was compared.The activity of alanine aminotransferase(ALT)and aspartate aminotransferase(AST)in serum was detected by an automatic biochemical instrument.The pathological changes of liver tissues were ob-served by HE staining.The mRNA expression levels of heme oxygenase-1(HO-1)and NAD(P)H-quinone oxidoreductase 1(NQO1)were detected by RT-qPCR,and the protein expression levels of HO-1,NQO1 and Ki67 were detected by Western blot and immunohistochemistry.RESULTS:Compared with normal control group,the body weight of the mice in model group was decreased significantly(P＜0.01),the liver index was increased significantly(P＜0.01),and the se-rum levels of ALT and AST were increased obviously(P＜0.01).There was no significant difference in the mRNA expres-sion levels of HO-1 and NQO1(P＞0.05),the protein levels of HO-1 and NQO1 were increased distinctly(P＜0.05),and the positive expression rate of Ki67 was increased significantly(P＜0.05).After curcumin treatment,the body weight of the mice was significantly increased(P＜0.01),the liver index was not changed(P＞0.05),and the number of tumor nodules in the liver was decreased significantly(P＜0.05 or P＜0.01).The serum level of AST was decreased significantly(P＜0.01),the mRNA and protein expression levels of HO-1 and NQO1 were decreased significantly(P＜0.05),and the posi-tive expression rate of Ki67 was decreased significantly(P＜0.05).CONCLUSION:Curcumin significantly protects against liver cancer in a C57BL/6J mouse model induced by DEN combined with CCl4,and its mechanism may be related to the inhibition of HO-1 and NQO1 expression.
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Objective:To explore the expression and clinical significance of heme oxygenase-1 (HO-1) and quinone oxidoreductase (NQO-1) in children with different severity levels of mycoplasma pneumoniae (MP) infection.Methods:A total of 140 children with MP infection who were treated at the Affiliated Hospital of Jining Medical University from January to June 2022 were selected as the observation group, while 100 healthy children who underwent physical examination were selected as the control group. The serum levels of interleukin-2 (IL-2), IL-6, IL-10, IL-1β, tumor necrosis factor α (TNF-α), interferon γ (IFN-γ), HO-1, and relative expression of NQO-1 protein were compared between the control group and the observation group, as well as between children with different degrees of MP infection, Forced vital capacity (FVC), maximum expiratory volume in the first second (FEV 1), peak expiratory flow rate (PEF), 50% forced expiratory flow rate and maximum mid expiratory flow rate (MEF 25-70), 50% forced expiratory flow rate (MEF 50), and 25% forced expiratory flow rate (MEF 25). Pearson correlation method was used to analyze the correlation between the expression of HO-1 and NQO-1 with inflammatory factors and lung function indicators. The receiver operating characteristic (ROC) curve was used to analyze the value of HO-1 and NQO-1 expression in predicting severe MP. Results:The serum levels of IL-2, IL-6, IL-10, IL-1β, TNF-α, IFN-γ, and HO-1 in the observation group were significantly higher than those in the control group (all P<0.05), while the relative expression level of NQO-1 protein was significantly lower than that in the control group ( P<0.05). The FVC, FEV 1, PEF, MEF 25-70, MEF 50, and MEF 25 in the observation group were significantly lower than those in the control group (all P<0.05). The serum levels of IL-2, IL-6, IL-10, IL-1β, TNF-α, IFN-γ, and HO-1 in the observation group of severe children were significantly higher than those in mild children (all P<0.05), while the relative expression of NQO-1 protein, FVC, FEV 1, PEF, MEF 25-70, MEF 50, and MEF 25 were significantly lower than those in mild children (all P<0.05). HO-1 in children with MP infection is positively correlated with IL-6, IL-1β, and IFN-γ, while the relative expression level of NQO-1 protein is negatively correlated with IL-6, IL-1β, and IFN-γ (all P<0.05); HO-1 was negatively correlated with MEF 50 and MEF 25, while the relative expression level of NQO-1 protein was positively correlated with MEF 50 (all P<0.05). The area under the ROC curve for predicting the relative expression levels of HO-1 and NQO-1 proteins in severe MP was 0.871 and 0.934, respectively (all P<0.05). Conclusions:The expression of serum HO-1 and NQO-1 in children with MP infection is correlated with cytokines and lung function indicators, and has certain application value in predicting severe illness.
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ObjectiveTo investigate the effect and mechanism of Shenqi Tangluo pill （SQTLP） on oxidative stress injury of skeletal muscle of type 2 diabetes mellitus （T2DM） mice based on nuclear factor erythroid 2-related factor 2 （Nrf2）/heme oxygenase-1 （HO-1）/NAD（P）H quinone oxidoreductase 1 （NQO1） pathway. MethodA total of 60 7-week-old male db/db mice ［specific pathogen-free （SPF） grade］ were selected and fed for one week for adaption. They were divided into the model control group， SQTLP low-， medium- and high-dose （19， 38， and 76 g·kg-1） groups and metformin group （0.26 g·kg-1） by gavage. Each group consisted of 12 mice. Twelve male db/m mice of the same age were selected as the blank group. The intervention was implemented continuously for 8 weeks. Fasting blood glucose （FBG） was detected. Fasting serum insulin （FINS） levels were detected by enzyme-linked immunosorbent assay （ELISA）， and the homeostasis model assessment-insulin resistance （HOMA-IR） index and the homeostasis model assessment-insulin sensitivity index （HOMA-ISI） were calculated. Oral glucose tolerance test （OGTT） and insulin tolerance test （ITT） were conducted. The activities of superoxide dismutase （SOD） and glutathione peroxidase （GSH-Px） and the contents of malondialdehyde （MDA） and reduced nicotinamide adenine dinucleotide phosphate （NADPH） in skeletal muscle tissues were detected by biochemical kits. Hematoxylin-eosin （HE） staining was used to observe the pathological changes in skeletal muscle tissues. The levels of reactive oxygen species （ROS） and 4-hydroxynonenal （4-HNE） in skeletal muscle tissue were detected by immunofluorescence （IF）. The expression levels of Nrf2， HO-1， NQO1 and glutamate-cysteine ligase catalytic subunit （GCLC） proteins in skeletal muscle tissues were detected by Western blot. ResultCompared with those in the blank group， FBG， FINS and HOMA-IR in the model group were significantly increased （P<0.05）， while HOMA-ISI was decreased （P<0.05）. The results of OGTT and ITT showed that blood glucose was significantly increased at all time points （P<0.05）， and glucose tolerance and insulin tolerance were significantly impaired. SOD and GSH-Px activities in skeletal muscle tissues were significantly decreased （P<0.05）， and MDA and NADPH contents were significantly increased （P<0.05）. In skeletal muscle tissues， the arrangement of muscle fibers was loose， the nucleus was disordered， and inflammatory cells were infiltrated. The expression levels of ROS and 4-HNE in skeletal muscle tissues were significantly increased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly decreased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the metformin group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that blood glucose in the metformin group was significantly decreased at all time points （P<0.05）. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue of the metformin group. The expressions of ROS and 4-HNE in skeletal muscle tissues were decreased （P<0.05）. The protein expression levels of Nrf2， HO-1， NQO1 and GCLC in skeletal muscle tissues were significantly increased （P<0.05）. Compared with those in the model group， FBG， FINS and HOMA-IR in the SQTLP medium- and high-dose groups were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the glucose tolerance and insulin tolerance of mice were improved in each dose group of SQTLP. The GSH-Px activity in the SQTLP low-dose group was significantly increased （P<0.05）， and the NADPH content was decreased （P<0.05）. The activities of SOD and GSH-Px in the SQTLP medium- and high-dose groups were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. The skeletal muscle tissue injury of mice in each dose group of SQTLP was ameliorated to different degrees. In the SQTLP medium- and high-dose groups， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05）. Compared with those in the SQTLP low-dose group， FBG and HOMA-IR in the SQTLP high-dose group were significantly decreased （P<0.05）， while HOMA-ISI was increased （P<0.05）. The results of OGTT and ITT showed that the SQTLP high-dose group significantly improved the glucose tolerance and insulin tolerance of mice. The activities of SOD and GSH-Px in skeletal muscle tissues were significantly increased （P<0.05）， while the contents of MDA and NADPH were significantly decreased （P<0.05）. No obvious abnormality was found in the skeletal muscle tissue， the expressions of ROS and 4-HNE were decreased （P<0.05）， and the protein expression levels of Nrf2， HO-1， NQO1 and GCLC were significantly increased （P<0.05） in the skeletal muscle tissue of the SQTLP high-dose group. ConclusionSQTLP can significantly improve IR in T2DM mice， and the mechanism is related to SQTLP activating the Nrf2/HO-1/NQO1 signaling pathway， promoting the expression of antioxidant enzymes， and thus improving the oxidative stress injury in the skeletal muscle.
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[Objective]To investigate the protective effect and mechanism of Ganoderma lucidum extract(GLE)on liver cirrhosis in mice.[Methods]Ten male C57BL/6 mice were randomly selected as control group,the remaining forty mice were intraperitoneally injected with carbon tetrachloride olive oil suspension to induce liver cirrhosis model.They were randomly divided into model group and GLE low(50 mg/kg·d),medium(100 mg/kg·d)and high(200 mg/kg·d)dose groups,while the control group and model group received 0.9％sodium chloride solution gastric irrigation,and the control group mice were given the same volume of olive oil solution twice a week.Liver index was calculated.The activities of alanine aminotransferase(ALT),aspartate transaminase(AST)and the levels of total cholesterol(TC),total bilirubin(TB)and creatinine(Cr)in serum of mice were detected by automatic biochemical analyzer.Hematoxylin eosin(HE)staining was used to observe the histopathological changes of liver,and Masson staining was used to observe the degree of liver fibrosis.Terminal-deoxynucleotidyl transferase mediated dUTP nick end labeling(TUNEL)staining was used to observe the apoptosis of hepatocytes.The levels of tumor necrosis factor-α(TNF-α),interleukin-1β(IL-1β),IL-6,malondialdehyde(MDA)and activity of superoxide dismutase(SOD)and glutathione peroxidase(GSH-Px)in serum were detected by enzyme linked immunosorbent assay(ELISA).The relative expression of nuclear factor E2 related factor 2(Nrf2)and nuclear Nrf2,heme oxygenase-1(HO-1)and NAD(P)H:quinone oxidoreductase 1(NQO1),α-smooth muscle actin(α-SMA),Collagen Ⅰ and E-cadherin protein in liver tissue were detected by Western blot.[Results]Compared with control group,the liver had significant damage,the liver index,serum ALT,AST activities,TC,TB and Cr levels,liver fibrosis degree,hepatocyte apoptosis index,the levels of serum TNF-α,IL-1 β,IL-6 and MDA,the relative expression of α-SMA and Collagen I protein increased(P＜0.05),while the activity levels of serum SOD and GSH-Px,and the relative expression of total Nrf2 and nuclear Nrf2,HO-1,NQO1 and E-cadherin protein in liver tissue decreased in model group(P＜0.05).Compared with model group,liver injury gradually reduced,the liver index,serum ALT,AST activities,TC,TB and Cr levels,liver fibrosis degree,hepatocyte apoptosis index,the levels of serum TNF-α,IL-1β,IL-6,MDA and the relative expression of α-SMA,Collagen I protein decreased(P＜0.05),while the activity levels of serum SOD and GSH-Px,and the relative expression of Nrf2 and nuclear Nrf2,HO-1,NQO1 and E-cadherin protein in liver tissue increased in GLE low,medium and high dose groups(P＜0.05).[Conclusion]GLE can alleviate the histopathological damage and improve liver function in cirrhotic mice.This may be related to the decreased level of oxidative stress and inflammatory reaction after activation of Nrf2/ARE signaling pathway,which may interfere with liver fibrosis.
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ObjectiveTo investigate the effect of linalool against acute liver injury induced by aflatoxin B1（AFB1） in rats and explore its protective mechanism. MethodTwenty male SPF SD rats were randomly divided into three groups： Control （n=6）， AFB1 （n=7）， and linalool （n=7） groups. Linalool solution （200 mg·kg-1） was administered preventatively for 14 days， while the control and AFB1 groups intragastrically received an equivalent volume of double distilled water. After preventative administration of linalool， AFB1 solution （1 mg·kg-1， dissolved in saline） was intraperitoneally injected for two consecutive days to induce acute liver injury in rats. Samples were collected and processed 14 days after model establishment. Pathological changes in liver tissue of rats were observed using Hematoxylin-eosin（HE） staining and Masson staining. Biochemical detection was performed to measure the levels of alanine transaminase（ALT）， aspartate transaminase（AST）， γ-glutamyl transferase（GGT）， lactate dehydrogenase（LDH）， alkaline phosphatase（ALP）， total bilirubin（TBil）， direct bilirubin（DBil）， indirect bilirubin（IBil）， malondialdehyde（MDA）， superoxidedismutase（SOD）， catalase（CAT） ， glutathione（GSH）， Fe3+， and Fe2+ in the liver tissue. Western blot was adopted to assess protein expression levels of nuclear factor-erythroid 2-related factor 2（Nrf2） and heme oxygenase-1（HO-1）. Molecular docking was performed to verify the binding between linalool and key proteins of the Nrf2/HO-1 signaling pathway. Molecular dynamics techniques were used to confirm the stability and affinity of linalool binding with key proteins of the Nrf2/HO-1 signaling pathway. ResultPathological results showed that compared to that in the AFB1 group， the liver structure in the linalool group tended to be normal， with a significant decrease in blue collagen fibers. The linalool group exhibited significantly reduced levels of ALT， AST， GGT， LDH， ALP， TBil， DBil， and IBil （P<0.01）， Fe3+ and Fe2+ content， and oxidative stress marker MDA （P<0.01）. The levels of antioxidants SOD， CAT， and GSH significantly increased （P<0.01）. Molecular docking showed a molecular docking energy between linalool and Nrf2 and HO-1 targets of -5.495 6 and -5.199 4 kcal·mol-1（1 cal≈4.186 J）， respectively. Molecular dynamics results indicated strong affinity in the binding of linalool with Nrf2 and HO-1. Western blot revealed a significant increase in Nrf2 protein expression （P<0.05） and a decrease in HO-1 protein expression （P<0.01） in the linalool group. ConclusionLinalool may protect against AFB1-induced acute liver injury by modulating the Nrf2/HO-1 ferroptosis signaling pathway to inhibit liver cell ferroptosis and regulate hepatic oxidative stress levels.
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ObjectiveTo investigate the effect and mechanism of Zhenwutang on renal oxidative damage in the mouse model of diabetic kidney disease with the syndrome of spleen-kidney Yang deficiency via the nuclear factor erythroid 2-related factor-2 （Nrf2）/heme oxygenase-1 （HO-1）/glutathione peroxidase 4 （GPX4） signaling pathway. MethodTwenty-five 7-week-old SPF-grade male db/m mice and 95 7-week-old SPF-grade male db/db mice were adaptively fed for a week. A blank group was set with the db/m mice without treatment， and the other mice were administrated with Rhei Radix et Rhizoma decoction and hydrocortisone for the modeling of diabetic kidney disease with the syndrome of spleen-kidney Yang deficiency. The modeled mice were randomized into the model， irbesartan （25 mg·kg-1）， and high-， medium-， low-dose （33.8， 16.9， 8.45 g·kg-1） Zhenwutang groups （n=15） and administrated with corresponding drugs for 8 weeks. The survival status of mice was observed， and the traditional Chinese medicine （TCM） syndrome score was recorded. The indicators related to spleen-kidney Yang deficiency， fasting blood glucose （FBG）， and renal function indicators were determined. Hematoxylin-eosin staining was employed to observe the histopathological changes of the renal tissue in each group. Biochemical kits were used to determine the oxidative stress-related indicators in the renal tissue. Real-time polymerase chain reaction and Western blotting were employed to determine the mRNA and protein levels， respectively， of Nrf2， HO-1， glutamate-cysteine ligase catalytic subunit （GCLC）， and GPX4 in the renal tissue of mice in each group. ResultCompared with the blank group， the modeling increased the TCM syndrome score （P<0.05）， elevated the estradiol （E2） and FBG levels （P<0.05）， lowered the testosterone （T）， triiodothyronine （T3）， and tetraiodothyronine （T4） levels （P<0.05）， and weakened the renal function （P<0.05）. In addition， the modeling led to glomerular hypertrophy and glomerular mesangial and basal thickening， decreased the catalase （CAT） activity， total antioxidant capacity （T-AOC）， and glutathione （GSH） content （P<0.05）， increased the malondialdehyde （MDA） content （P<0.05）， and down-regulated the mRNA and protein levels of Nrf2， HO-1， GCLC， and GPX4 in the renal tissue （P<0.05）. Compared with the model group， high and medium doses of Zhenwutang decreased the TCM syndrome score and E2 content （P<0.05）， increased the T， T3， and T4 content （P<0.05）， improved the renal function （P<0.05）， alleviated the pathological changes in the renal tissue， increased CAT， T-AOC， and GSH （P<0.05）， reduced MDA （P<0.05）， and up-regulated the mRNA and protein levels of Nrf2， HO-1， GCLC， and GPX4 in the renal tissue （P<0.05）. ConclusionZhenwutang can improve the general state and renal function and reduce the oxidative damage and pathological changes in the renal tissue of db/db mice with spleen-kidney Yang deficiency by regulating the Nrf2/HO-1/GPX4 signaling pathway.
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Objective:To evaluate the role of nuclear factor E2-related factor 2 (Nrf2)/heme oxidase-1 (HO-1) in reduction of renal ischemia-reperfusion (I/R) injury by the human umbilical cord mesenchymal stem cells (hucMSCs)-derived exosomes (hucMSCs-exo) in mice.Methods:The hucMSCs were cultured, and exosomes were extracted and identified by transmission electron microscopy, nanoparticle tracking analysis and Western blot. Thirty-six male SPF-grade C57BL/6 mice, weighing 20-25 g, were used. Thirty mice were selected and divided into 5 groups ( n=6 each) by a random number table method: sham operation group (Sham group), sham operation + Nrf2 inhibitor ML385 group (Sham + ML385 group), renal I/R group (I/R group), renal I/R + exosome group (I/R+ EXO group), and renal I/R + exosome + Nrf2 inhibitor ML385 group (I/R+ EXO+ ML385 group). A model of renal I/R injury was prepared by clamping the bilateral renal pedicles for 45 min followed by perfusion in anesthetized animals. ML385 30 mg/kg was intraperitoneally injected at 45 min before preparing the model in Sham+ ML385 group and I/R+ EXO+ ML385 group, and hucMSCs-exo 100 μg was injected via the tail vein at 15 min before reperfusion in I/R+ EXO group and I/R+ EXO+ ML385 group. Serum blood urea nitrogen (BUN) and creatinine (Cr) concentrations were detected at 24 h of reperfusion. The renal tissues were obtained for examination of the pathological changes and for determination of contents of interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α) and malondialdehyde (MDA), superoxide dismutase (SOD) activity and reactive oxygen species (ROS) levels and expression of Nrf2 and HO-1 protein and mRNA (by Western blot and quantitative real-time polymerase chain reaction). The left 6 mice were allocated to sham operation group (Sham-IM group, n=3) and renal I/R group (I/R-IM group, n=3) by a random number table method for VISQUE in living imaging observation. Results:The exosomes showed a typical cup-shaped morphology with a transmission electron microscope, the nanoparticles tracked and analyzed the average diameter of the exosome, with an average diameter of 96.7 nm, and the positive expression of surface markers CD9, CD63 and TSG101 was detected using Western blot. The renal fluorescence intensity value was significantly increased in I/R-IM group as compared with Sham-IM group ( P<0.05). Compared with Sham group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R group, and no significant change was found in serum BUN and Cr concentrations in Sham+ ML385 group ( P>0.05). Compared with I/R group, the serum BUN and Cr concentrations were significantly decreased, the contents of IL-6, TNF-α and MDA and ROS levels were decreased, the activity of SOD was increased, the expression of Nrf2 and HO-1 protein and mRNA was up-regulated ( P<0.05), and the pathological changes of renal tissues were significantly attenuated in I/R+ EXO group. Compared with I/R+ EXO group, the serum BUN and Cr concentrations were significantly increased, the contents of IL-6, TNF-α and MDA and ROS levels were increased, the activity of SOD was decreased, the expression of Nrf2 and HO-1 protein and mRNA was down-regulated ( P<0.05), and the pathological changes of renal tissues were aggravated in I/R+ EXO+ ML385 group. Conclusions:The mechanism by which hucMSCs-exo reduces renal I/R injury may be related to activation of the Nrf2/HO-1 signaling pathway in mice.
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ObjectiveTo investigate the protective effect of safranal against sepsis-related liver injury （SRLI） induced by lipopolysaccharide （LPS） in mice and its mechanism. MethodsA total of 32 experimental male C57BL/6 mice were divided into control group， single drug group， model group， and treatment group using the simple random method， with 8 mice in each group. The mice in the single drug group and the treatment group were intraperitoneally injected with safranal （60 mg/kg） for 7 days of pretreatment， and the mice in the model group and the treatment group were intraperitoneally injected with LPS （10 mg/kg） to induce acute liver injury. The activities of serum alanine aminotransferase （ALT） and aspartate aminotransferase （AST） were measured； HE staining was used to observe liver tissue sections； immunohistochemistry was used to analyze the expression of the downstream protein heme oxygenase-1 （HO-1） in the signal pathway； TUNEL was used to analyze the apoptosis of hepatocytes； Western blot was used to measure the expression of total proteins （nuclear factor erythroid 2-related factor 2 ［Nrf-2］ and HO-1） in liver tissue. The human liver cell line L02 was pretreated with safranal （100 μmol/L）， followed by induction of acute hepatocellular injury with LPS （100 ng/mL）， and DCFH-DA fluorescent labeling was used to detect reactive oxygen species （ROS）. ResultsAfter safranal pretreatment， the treatment group had significantly lower levels of ALT and AST than the model group （both P<0.001）， with a relatively intact pseudolobular structure and a smaller necrotic area in the liver. Compared with the model group， the treatment group had significant increases in the expression levels of Nrf2 and HO-1 in liver tissue after safranal+LPS treatment （both P<0.001）， and immunohistochemistry showed that safranal pretreatment increased the number of HO-1-positive cells. In the cell model of LPS-induced acute liver injury， the treatment group had a significant reduction in the production of ROS compared with the model group. ConclusionSafranal can exert a protective effect against SRLI induced by LPS in mice through the Nrf2/HO-1 pathway.
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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.
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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.
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The incidence rate of alcoholic liver disease (ALD) is increasing year by year China, and there is a gradual increase in disease burden among Chinese people. Oxidative stress response in hepatocytes is an important pathogenic mechanism of ALD. The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) signaling pathway is an important endogenous anti-oxidative stress pathway in the body, and Nrf2 is activated in response to oxidative stress and exerts its transcriptional activity to induce high HO-1 expression. HO-1 is an important oxidative stress response protein and plays a role in anti-inflammation, anti- oxidation, and cell apoptosis regulation together with heme hydrolysis products (bilirubin, carbon monoxide, and iron). This article reviews the research advances in the role of the Nrf2/HO-1 signaling pathway in ALD in recent years, so as to find a theoretical basis for the development and progression of ALD and an entry point for treatment.
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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.
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Liver transplantation is a vital treatment for end-stage liver disease. However, the shortage of donor livers has limited the development of liver transplantation. How to expand the source of donor livers has become a challenge in the academic community. In recent years, the proportion of donors with non-alcoholic fatty liver disease (NAFLD) has been increased. Rational use of steatotic donor livers is a feasible approach to expand the donor pool. Cold ischemia injury during donor liver preservation before liver transplantation increases the risk of postoperative organ dysfunction. Therefore, it is of significance to unravel the mechanism and intervention measures of cold ischemia injury of steatotic donor livers. Cold ischemia injury of steatotic donor livers is characterized as the damage of mitochondria, lysosomes and endoplasmic reticulum at the organelle level, and up-regulated expression of adenosine monphosphate activated protein kinase (AMPK), aldehyde dehydrogenase 2 (ALDH2) and heme oxygenase (HO)-1 at the protein level. In this article, the research progresses on cold ischemia injury of steatotic donor livers and relevant intervention measures were reviewed.