Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic development.Lut...Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic development.Luteolin(Lut)has been documented for its protective effects against oxidative stress in various studies.However,its specific role in embryonic development remains unexplored.This study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying mechanism.Results After undergoing parthenogenetic activation(PA)or in vitro fertilization,embryos supplemented with 0.5μmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates,with an increase in total cell numbers and a decrease in the apoptosis rate compared to the control.Measurements on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the control.Moreover,Lut supplementation significantly augmented mitochondrial content and membrane potential.Intriguingly,activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut,leading to the upregulation of antioxidant-related gene transcription levels.To further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development,we cultured PA embryos in a medium supplemented with brusatol,with or without the inclusion of Lut.The positive effects of Lut on developmental competence were negated by brusatol treatment.Conclusions Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence,and offers insight into the mechanisms regulating early embryonic development.展开更多
BACKGROUND Diabetic foot ulcers(DFU),as severe complications of diabetes mellitus(DM),significantly compromise patient health and carry risks of amputation and mortality.AIM To offer new insights into the occurrence a...BACKGROUND Diabetic foot ulcers(DFU),as severe complications of diabetes mellitus(DM),significantly compromise patient health and carry risks of amputation and mortality.AIM To offer new insights into the occurrence and development of DFU,focusing on the therapeutic mechanisms of X-Paste(XP)of wound healing in diabetic mice.METHODS Employing traditional Chinese medicine ointment preparation methods,XP combines various medicinal ingredients.High-performance liquid chromatography(HPLC)identified XP’s main components.Using streptozotocin(STZ)-induced diabetic,we aimed to investigate whether XP participated in the process of diabetic wound healing.RNA-sequencing analyzed gene expression differences between XP-treated and control groups.Molecular docking clarified XP’s treatment mechanisms for diabetic wound healing.Human umbilical vein endothelial cells(HUVECs)were used to investigate the effects of Andrographolide(Andro)on cell viability,reactive oxygen species generation,apoptosis,proliferation,and metastasis in vitro following exposure to high glucose(HG),while NF-E2-related factor-2(Nrf2)knockdown elucidated Andro’s molecular mechanisms.RESULTS XP notably enhanced wound healing in mice,expediting the healing process.RNA-sequencing revealed Nrf2 upregulation in DM tissues following XP treatment.HPLC identified 21 primary XP components,with Andro exhibiting strong Nrf2 binding.Andro mitigated HG-induced HUVECs proliferation,metastasis,angiogenic injury,and inflammation inhibition.Andro alleviates HG-induced HUVECs damage through Nrf2/HO-1 pathway activation,with Nrf2 knockdown reducing Andro’s proliferative and endothelial protective effects.CONCLUSION XP significantly promotes wound healing in STZ-induced diabetic models.As XP’s key component,Andro activates the Nrf2/HO-1 signaling pathway,enhancing cell proliferation,tubule formation,and inflammation reduction.展开更多
Objective:To observe the protective effect of hesperidin on myocardial ischemia/reperfusion injury in type 2 diabetes mellitus and its effect on SIRT1/Nrf2/HO-1 signaling pathway.Methods:50 Sprague-Dawley(SD)rats were...Objective:To observe the protective effect of hesperidin on myocardial ischemia/reperfusion injury in type 2 diabetes mellitus and its effect on SIRT1/Nrf2/HO-1 signaling pathway.Methods:50 Sprague-Dawley(SD)rats were randomly assigned to the normal control group(NC),model group,ischemia-reperfusion group(IR),hesperidin group,SIRT1 inhibitor group and hesperidin plus SIRT1 inhibitor group.In addition to NC,the rats in the remaining groups were replicated by intraperitoneal of high-fat diet combined with injection of streptozotocin for type 2 diabetic rats.After then,the myocardial ischemia/reperfusion injury(MIRI)rat model was established by LAd for 30 minutes with 2 hours reperfusion.He staining was used to observe the pathological changes of myocardial tissue,and the levels of serum LDH,CK-MB and SOD,GSH and MDA in myocardial tissue were detected by kit methods,and the expression abundance of related proteins in 4-HNE and SIRT1/Nrf2/HO-1 signal pathway were detected by immunohistochemistry and Western blot;Results:Hesperidin could significantly inhibit cardiomyocyte necrosis and inflammatory cell infiltration,reduce LDH activity,CK-MB and MDA level,and increase SOD activity,GSH and 4-HNE level,the differences were statistically significant when compared with IR group(P<0.01).In addition,compared with the ischemia-reperfusion group,the expressions of SIRT1,Nrf2 and HO-1 proteins in hesperidin group were significantly up-regulated,the differences were statistically significant(P<0.01);Conclusion:Hesperidin inhibits oxidative stress by activating SIRT1/Nrf2/HO-1 signaling pathway,and play a protective effect of myocardial ischemia reperfusion injury in diabetic rats.展开更多
Objective:This study aimed to explore the therapeutic effect of nuciferine on high-fat diet-induced obesity in rats and the influence of nuciferine on nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1...Objective:This study aimed to explore the therapeutic effect of nuciferine on high-fat diet-induced obesity in rats and the influence of nuciferine on nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)signaling pathway in the adipose tissue.Methods:A total of 40 male Sprague Dawley(SD)rats were evenly divided into the normal,model,positive control,and nuciferine groups,using the random number table method.Except for the normal group,rats in the other groups were fed with high-fat diet for 12 weeks to establish the obesity model.During the model establishment,rats in the positive control group received atorvastatin calcium 2 mg/kg,rats in the nuciferine group received nuciferine 20 mg/kg,and rats in the normal and model groups received normal saline 2 mL,daily through intragastric administration for 12 consecutive weeks.After model establishment and administration,the body weight,Lee’s index,and blood lipids of rats in each group were measured,and hematoxylin and eosin(HE)staining was performed on the liver and adipose tissues to evaluate the therapeutic effect of nuciferine on obesity rat model.Additionally,the levels of superoxide dismutase(SOD),malondialdehyde(MDA),and glutathione peroxidase(GSH-Px)in the serum of rats in each group were determined,and the gene expressions of Nrf2 and HO-1 in the adipose tissue of rats in each group were detected through quantitative polymerase chain reaction(qPCR)to investigate the mechanism of action of nuciferine in the treatment of obesity.Results:After 12 weeks of model establishment and administration,we observed that compared with the model group,nuciferine could significantly reduce the body weight,Lee’s index,and serum triglyceride(TG),total cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C)levels and increase the serum high-density lipoprotein cholesterol(HDL-C)level in obesity rat model(P<0.05 or P<0.01).HE staining revealed that nuciferine could significantly alleviate liver steatosis in obesity rat model and improve the cell morphology in epididymal adipose tissue.Moreover,nuciferine could elevate serum SOD and GSH-Px activities in obesity rat model and lower the serum MDA level(P<0.05 or P<0.01).The qPCR indicated that nuciferine could upregulate the gene expression of Nrf2 and HO-1 in the adipose tissue of obesity rat model(P<0.05 or P<0.01).展开更多
Objective:To investigate the protective mechanism of Xuduan Zhongzi prescription against epididymal oxidative damage in oligoasthenospermia model rats.Methods:Forty SD rats were randomly divided into blank group,model...Objective:To investigate the protective mechanism of Xuduan Zhongzi prescription against epididymal oxidative damage in oligoasthenospermia model rats.Methods:Forty SD rats were randomly divided into blank group,model group,Xuduan Zhongzi prescription group(10g/kg)and L-carnitine group(0.1g/kg).Except blank group,all induced oligoasmospermia.The blank group and model group were given normal saline intragastric administration,the Xuduan Zhongzi prescription group was given Xuduan Zhongzi prescription solution intragastric administration,and the L-carnitine group was given L-carnitine intragastric administration.HE staining was used to observe the epididymis structure after 8 weeks.The concentration and activity rate of epididymis sperm were measured by sperm quality.MRNA and protein expression levels of Nrf2,NQO1 andγ-GCs in epididymis were detected by RT-qPCR and immunohistochemistry.Results:①HE staining:in the blank group,the epididymis tubes were arranged tightly and regularly,the tissue structure was complete,the epithelial cells were arranged orderly,and the lumen sperm were numerous and evenly distributed.The epididymis of model group showed structural atrophy,loose arrangement,enlarged mesenchyme,increased cell debris and significantly reduced sperm cells.Compared with the model group,the lumen lesions of epididymis in Xuduan Zhongzi prescription group and L-carnitine group were significantly improved,and the amount of normal sperm in lumen was increased and the distribution was uniform.②Results of sperm quality comparison among each group:sperm density and sperm motility rate:compared with blank group,sperm density and sperm motility rate in other groups were significantly decreased(P<0.05),and sperm density and sperm motility rate in model group were significantly decreased(P<0.05);Compared with model group,the sperm density and motility rate in Xuduan Zhongzi prescription group and L-carnitine group were significantly increased(P<0.05).③RT-qPCR and immunohistochemistry:Compared with the blank group,the mRNA and protein levels of Nrf2,NQO1 andγ-GCs in epididymal rats in model group were significantly decreased(P<0.05),while the mRNA and protein levels of Nrf2,NQO1 andγ-GCs were significantly increased in L-carnitine group and Continua seed formula group(P<0.05).Conclusion:Xuduan Zhongzi prescription can reduce oxidative stress damage and improve sperm quality of oligoasthenospermia.The mechanism may related to promoting the activation of Nrf2-NQO1/γ-GCS pathway in epididymis of oligoasthenospermia rats,and up-regulate the expressions of Nrf2,NQO1 andγ-GCS proteins.展开更多
Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in...Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in CD-1 mice(Beijing Vital River Laboratory Animal Technology, Beijing, China) by occluding the right middle cerebral artery for 1 hour and allowing reperfusion for 24 hours. After intraperitoneally injecting model mice with 10, 20, or 40 mg/kg RA, functional neurological deficits were evaluated using modified Longa scores. Subsequently, cerebral infarct volume was measured using TTC staining and ischemic brain tissue was examined for cell apoptosis with TUNEL staining. Superoxide dismutase activity and malondialdehyde levels were measured by spectrophometry. Expression of heme oxygenase-1(HO-1), nuclear factor erythroid 2-related factor 2(Nrf2), Bcl-2, Bax, Akt, and phospho-Ser473 Akt proteins in ischemic brain tissue was detected by western blot, while mRNA levels of Nrf2, HO-1, Bcl-2, and Bax were analyzed using real time quantitative PCR. In addition, HO-1 enzyme activity was measured spectrophotometrically. RA(20 and 40 mg/kg) greatly improved neurological function, reduced infarct volume, decreased cell apoptosis, upregulated Bcl-2 protein and mRNA expression, downregulated Bax protein and mRNA expression, increased HO-1 and Nrf2 protein and mRNA expression, increased superoxide dismutase activity, and decreased malondialdehyde levels in ischemic brain tissue of model mice. However, intraperitoneal injection of a HO-1 inhibitor(10 mg/kg zinc protoporphyrin IX) reversed the neuroprotective effects of RA on HO-1 enzyme activity and Bcl-2 and Bax protein expression. The PI3 K/Akt signaling pathway inhibitor LY294002(10 mM) inhibited Akt phosphorylation, as well as Nrf2 and HO-1 expression. Our findings suggest that RA has anti-oxidative and anti-apoptotic properties that protect against ischemic stroke by a mechanism involving upregulation of Nrf2 and HO-1 expression via the PI3 K/Akt signaling pathway.展开更多
基金supported by the Korea Research Institute of Bioscience and Biotechnology(KRIBB)Research Initiative Program(KGM4252331,KGM5382322),Republic of Korea.
文摘Background Oxidative stress,caused by an imbalance in the production and elimination of intracellular reactive oxygen species(ROS),has been recognized for its detrimental effects on mammalian embryonic development.Luteolin(Lut)has been documented for its protective effects against oxidative stress in various studies.However,its specific role in embryonic development remains unexplored.This study aims to investigate the influence of Lut on porcine embryonic development and to elucidate the underlying mechanism.Results After undergoing parthenogenetic activation(PA)or in vitro fertilization,embryos supplemented with 0.5μmol/L Lut displayed a significant enhancement in cleavage and blastocyst formation rates,with an increase in total cell numbers and a decrease in the apoptosis rate compared to the control.Measurements on D2 and D6 revealed that embryos with Lut supplementation had lower ROS levels and higher glutathione levels compared to the control.Moreover,Lut supplementation significantly augmented mitochondrial content and membrane potential.Intriguingly,activation of the Nrf2/Keap1 signaling pathway was observed in embryos supplemented with Lut,leading to the upregulation of antioxidant-related gene transcription levels.To further validate the relationship between the Nrf2/Keap1 signaling pathway and effects of Lut in porcine embryonic development,we cultured PA embryos in a medium supplemented with brusatol,with or without the inclusion of Lut.The positive effects of Lut on developmental competence were negated by brusatol treatment.Conclusions Our findings indicate that Lut-mediated activation of the Nrf2/Keap1 signaling pathway contributes to the enhanced production of porcine embryos with high developmental competence,and offers insight into the mechanisms regulating early embryonic development.
基金Supported by the Shanghai Science and Technology Innovation Project,One Belt One Road International Joint Laboratory of Medical Mycology,No.21410750500。
文摘BACKGROUND Diabetic foot ulcers(DFU),as severe complications of diabetes mellitus(DM),significantly compromise patient health and carry risks of amputation and mortality.AIM To offer new insights into the occurrence and development of DFU,focusing on the therapeutic mechanisms of X-Paste(XP)of wound healing in diabetic mice.METHODS Employing traditional Chinese medicine ointment preparation methods,XP combines various medicinal ingredients.High-performance liquid chromatography(HPLC)identified XP’s main components.Using streptozotocin(STZ)-induced diabetic,we aimed to investigate whether XP participated in the process of diabetic wound healing.RNA-sequencing analyzed gene expression differences between XP-treated and control groups.Molecular docking clarified XP’s treatment mechanisms for diabetic wound healing.Human umbilical vein endothelial cells(HUVECs)were used to investigate the effects of Andrographolide(Andro)on cell viability,reactive oxygen species generation,apoptosis,proliferation,and metastasis in vitro following exposure to high glucose(HG),while NF-E2-related factor-2(Nrf2)knockdown elucidated Andro’s molecular mechanisms.RESULTS XP notably enhanced wound healing in mice,expediting the healing process.RNA-sequencing revealed Nrf2 upregulation in DM tissues following XP treatment.HPLC identified 21 primary XP components,with Andro exhibiting strong Nrf2 binding.Andro mitigated HG-induced HUVECs proliferation,metastasis,angiogenic injury,and inflammation inhibition.Andro alleviates HG-induced HUVECs damage through Nrf2/HO-1 pathway activation,with Nrf2 knockdown reducing Andro’s proliferative and endothelial protective effects.CONCLUSION XP significantly promotes wound healing in STZ-induced diabetic models.As XP’s key component,Andro activates the Nrf2/HO-1 signaling pathway,enhancing cell proliferation,tubule formation,and inflammation reduction.
基金Construction Project of Traditional Chinese Medicine Academic Genre Inheritance Studio of the State Administration of Traditional Chinese Medicine(No.LPGZS2012-14)Construction Project of National Famous and old Traditional Chinese Medicine Expert Inheritance Studio of the State Administration of Traditional Chinese Medicine。
文摘Objective:To observe the protective effect of hesperidin on myocardial ischemia/reperfusion injury in type 2 diabetes mellitus and its effect on SIRT1/Nrf2/HO-1 signaling pathway.Methods:50 Sprague-Dawley(SD)rats were randomly assigned to the normal control group(NC),model group,ischemia-reperfusion group(IR),hesperidin group,SIRT1 inhibitor group and hesperidin plus SIRT1 inhibitor group.In addition to NC,the rats in the remaining groups were replicated by intraperitoneal of high-fat diet combined with injection of streptozotocin for type 2 diabetic rats.After then,the myocardial ischemia/reperfusion injury(MIRI)rat model was established by LAd for 30 minutes with 2 hours reperfusion.He staining was used to observe the pathological changes of myocardial tissue,and the levels of serum LDH,CK-MB and SOD,GSH and MDA in myocardial tissue were detected by kit methods,and the expression abundance of related proteins in 4-HNE and SIRT1/Nrf2/HO-1 signal pathway were detected by immunohistochemistry and Western blot;Results:Hesperidin could significantly inhibit cardiomyocyte necrosis and inflammatory cell infiltration,reduce LDH activity,CK-MB and MDA level,and increase SOD activity,GSH and 4-HNE level,the differences were statistically significant when compared with IR group(P<0.01).In addition,compared with the ischemia-reperfusion group,the expressions of SIRT1,Nrf2 and HO-1 proteins in hesperidin group were significantly up-regulated,the differences were statistically significant(P<0.01);Conclusion:Hesperidin inhibits oxidative stress by activating SIRT1/Nrf2/HO-1 signaling pathway,and play a protective effect of myocardial ischemia reperfusion injury in diabetic rats.
基金This work was supported by the Science and Technology Project of Jiaxing.(No.2018AY3207)。
文摘Objective:This study aimed to explore the therapeutic effect of nuciferine on high-fat diet-induced obesity in rats and the influence of nuciferine on nuclear factor erythroid 2-related factor 2(Nrf2)/heme oxygenase-1(HO-1)signaling pathway in the adipose tissue.Methods:A total of 40 male Sprague Dawley(SD)rats were evenly divided into the normal,model,positive control,and nuciferine groups,using the random number table method.Except for the normal group,rats in the other groups were fed with high-fat diet for 12 weeks to establish the obesity model.During the model establishment,rats in the positive control group received atorvastatin calcium 2 mg/kg,rats in the nuciferine group received nuciferine 20 mg/kg,and rats in the normal and model groups received normal saline 2 mL,daily through intragastric administration for 12 consecutive weeks.After model establishment and administration,the body weight,Lee’s index,and blood lipids of rats in each group were measured,and hematoxylin and eosin(HE)staining was performed on the liver and adipose tissues to evaluate the therapeutic effect of nuciferine on obesity rat model.Additionally,the levels of superoxide dismutase(SOD),malondialdehyde(MDA),and glutathione peroxidase(GSH-Px)in the serum of rats in each group were determined,and the gene expressions of Nrf2 and HO-1 in the adipose tissue of rats in each group were detected through quantitative polymerase chain reaction(qPCR)to investigate the mechanism of action of nuciferine in the treatment of obesity.Results:After 12 weeks of model establishment and administration,we observed that compared with the model group,nuciferine could significantly reduce the body weight,Lee’s index,and serum triglyceride(TG),total cholesterol(TC),and low-density lipoprotein cholesterol(LDL-C)levels and increase the serum high-density lipoprotein cholesterol(HDL-C)level in obesity rat model(P<0.05 or P<0.01).HE staining revealed that nuciferine could significantly alleviate liver steatosis in obesity rat model and improve the cell morphology in epididymal adipose tissue.Moreover,nuciferine could elevate serum SOD and GSH-Px activities in obesity rat model and lower the serum MDA level(P<0.05 or P<0.01).The qPCR indicated that nuciferine could upregulate the gene expression of Nrf2 and HO-1 in the adipose tissue of obesity rat model(P<0.05 or P<0.01).
基金The central government guides local science and technology development projects(No.Guike ZY20198022)Guangxi University of Traditional Chinese Medicine Graduate Education Innovation Program(No.YCSZ2020013,YCSY2020051,YCXJ2021067)。
文摘Objective:To investigate the protective mechanism of Xuduan Zhongzi prescription against epididymal oxidative damage in oligoasthenospermia model rats.Methods:Forty SD rats were randomly divided into blank group,model group,Xuduan Zhongzi prescription group(10g/kg)and L-carnitine group(0.1g/kg).Except blank group,all induced oligoasmospermia.The blank group and model group were given normal saline intragastric administration,the Xuduan Zhongzi prescription group was given Xuduan Zhongzi prescription solution intragastric administration,and the L-carnitine group was given L-carnitine intragastric administration.HE staining was used to observe the epididymis structure after 8 weeks.The concentration and activity rate of epididymis sperm were measured by sperm quality.MRNA and protein expression levels of Nrf2,NQO1 andγ-GCs in epididymis were detected by RT-qPCR and immunohistochemistry.Results:①HE staining:in the blank group,the epididymis tubes were arranged tightly and regularly,the tissue structure was complete,the epithelial cells were arranged orderly,and the lumen sperm were numerous and evenly distributed.The epididymis of model group showed structural atrophy,loose arrangement,enlarged mesenchyme,increased cell debris and significantly reduced sperm cells.Compared with the model group,the lumen lesions of epididymis in Xuduan Zhongzi prescription group and L-carnitine group were significantly improved,and the amount of normal sperm in lumen was increased and the distribution was uniform.②Results of sperm quality comparison among each group:sperm density and sperm motility rate:compared with blank group,sperm density and sperm motility rate in other groups were significantly decreased(P<0.05),and sperm density and sperm motility rate in model group were significantly decreased(P<0.05);Compared with model group,the sperm density and motility rate in Xuduan Zhongzi prescription group and L-carnitine group were significantly increased(P<0.05).③RT-qPCR and immunohistochemistry:Compared with the blank group,the mRNA and protein levels of Nrf2,NQO1 andγ-GCs in epididymal rats in model group were significantly decreased(P<0.05),while the mRNA and protein levels of Nrf2,NQO1 andγ-GCs were significantly increased in L-carnitine group and Continua seed formula group(P<0.05).Conclusion:Xuduan Zhongzi prescription can reduce oxidative stress damage and improve sperm quality of oligoasthenospermia.The mechanism may related to promoting the activation of Nrf2-NQO1/γ-GCS pathway in epididymis of oligoasthenospermia rats,and up-regulate the expressions of Nrf2,NQO1 andγ-GCS proteins.
基金supported by the National Natural Science Foundation of China,No.81571292(to XJZ)、81601152(to YY)the Natural Science Foundation of Hebei Province of China,No.H2017206338(to RC)
文摘Rosmarinic acid(RA) can elicit a neuroprotective effect against ischemic stroke, but the precise molecular mechanism remains poorly understood. In this study, an experimental ischemic stroke model was established in CD-1 mice(Beijing Vital River Laboratory Animal Technology, Beijing, China) by occluding the right middle cerebral artery for 1 hour and allowing reperfusion for 24 hours. After intraperitoneally injecting model mice with 10, 20, or 40 mg/kg RA, functional neurological deficits were evaluated using modified Longa scores. Subsequently, cerebral infarct volume was measured using TTC staining and ischemic brain tissue was examined for cell apoptosis with TUNEL staining. Superoxide dismutase activity and malondialdehyde levels were measured by spectrophometry. Expression of heme oxygenase-1(HO-1), nuclear factor erythroid 2-related factor 2(Nrf2), Bcl-2, Bax, Akt, and phospho-Ser473 Akt proteins in ischemic brain tissue was detected by western blot, while mRNA levels of Nrf2, HO-1, Bcl-2, and Bax were analyzed using real time quantitative PCR. In addition, HO-1 enzyme activity was measured spectrophotometrically. RA(20 and 40 mg/kg) greatly improved neurological function, reduced infarct volume, decreased cell apoptosis, upregulated Bcl-2 protein and mRNA expression, downregulated Bax protein and mRNA expression, increased HO-1 and Nrf2 protein and mRNA expression, increased superoxide dismutase activity, and decreased malondialdehyde levels in ischemic brain tissue of model mice. However, intraperitoneal injection of a HO-1 inhibitor(10 mg/kg zinc protoporphyrin IX) reversed the neuroprotective effects of RA on HO-1 enzyme activity and Bcl-2 and Bax protein expression. The PI3 K/Akt signaling pathway inhibitor LY294002(10 mM) inhibited Akt phosphorylation, as well as Nrf2 and HO-1 expression. Our findings suggest that RA has anti-oxidative and anti-apoptotic properties that protect against ischemic stroke by a mechanism involving upregulation of Nrf2 and HO-1 expression via the PI3 K/Akt signaling pathway.