Summary: In order to investigate the relationship between the expression of heme oxygenase-2 (HO-2) mRNA and the pathogenesis of Hirschsprung's disease (HD), total ribonucleic acid (RNA) was extracted in the agang...Summary: In order to investigate the relationship between the expression of heme oxygenase-2 (HO-2) mRNA and the pathogenesis of Hirschsprung's disease (HD), total ribonucleic acid (RNA) was extracted in the aganglionic and ganglionic segments of colon respectively from 15 cases of HD. The single-stranded cDNA of HO-2 was synthesized and further amplified by reverse transcription-polymerase chain reaction (RT-PCR). The expression of HO-2 mRNA was normal in ganglionic segments, but absent in aganglionic segments. It is concluded that the absence of HO-2 mRNA expression may be an important mechanism responsible for HD.展开更多
Interfering with the ferroptosis pathway is a new strategy for the treatment of spinal cord injury.Fibroblast growth factor 21 can inhibit ferro ptosis and promote neurofunctional recovery,while heme oxygenase-1 is a ...Interfering with the ferroptosis pathway is a new strategy for the treatment of spinal cord injury.Fibroblast growth factor 21 can inhibit ferro ptosis and promote neurofunctional recovery,while heme oxygenase-1 is a regulator of iron and reactive oxygen species homeostasis.The relationship between heme oxygenase-1and ferroptosis remains controve rsial.In this study,we used a spinal co rd injury rat model to show that the levels of fibroblast growth factor 21 in spinal co rd tissue decreased after spinal cord injury.In addition,there was a significant aggravation of ferroptosis and a rapid increase in heme oxygenase-1 expression after spinal cord injury.Furthe r,heme oxygenase-1 aggravated fe rroptosis after spinal cord injury,while fibroblast growth factor 21 inhibited fe rroptosis by downregulating heme oxygenase-1.Thus,the activation of fibroblast growth factor 21 may provide a potential treatment for spinal co rd injury.These findings could provide a new potential mechanistic explanation for fibroblast growth factor 21 in the treatment of spinal cord injury.展开更多
Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox...Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox homeostasis.Metformin is a classic drug used to treat type 2 diabetes that can inhibit ferroptosis.Previous studies have shown that,when used to treat cardiovascular and digestive system diseases,metformin can also upregulate heme oxygenase-1 expression.Therefore,we hypothesized that heme oxygenase-1 plays a significant role in mediating the beneficial effects of metformin on neuronal ferroptosis after spinal cord injury.To test this,we first performed a bioinformatics analysis based on the GEO database and found that heme oxygenase-1 was upregulated in the lesion of rats with spinal cord injury.Next,we confirmed this finding in a rat model of T9 spinal cord compression injury that exhibited spinal cord nerve cell ferroptosis.Continuous intraperitoneal injection of metformin for 14 days was found to both upregulate heme oxygenase-1 expression and reduce neuronal ferroptosis in rats with spinal cord injury.Subsequently,we used a lentivirus vector to knock down heme oxygenase-1 expression in the spinal cord,and found that this significantly reduced the effect of metformin on ferroptosis after spinal cord injury.Taken together,these findings suggest that metformin inhibits neuronal ferroptosis after spinal cord injury,and that this effect is partially dependent on upregulation of heme oxygenase-1.展开更多
AIM:To investigate the efficacy and molecularmechanisms of induced heme oxygenase(HO)-1 in protecting liver from warm ischemia/reperfusion(I/R)injury.METHODS:Partial warm ischemia was produced in the left and middle h...AIM:To investigate the efficacy and molecularmechanisms of induced heme oxygenase(HO)-1 in protecting liver from warm ischemia/reperfusion(I/R)injury.METHODS:Partial warm ischemia was produced in the left and middle hepatic lobes of SD rats for 75min,followed by 6 h of reperfusion.Rats were treated with saline,cobalt protoporphyrin(Co PP)or zinc protoporphyrin(Zn PP)at 24 h prior to the ischemia insult.Blood and samples of ischemic lobes subjected to ischemia were collected at 6 h after reperfusion.Serum transaminases level,plasma lactate dehydrogenase and myeloperoxidase activity in liver were measured.Liver histological injury and inflammatory cell infiltration were evaluated by tissue section and liver immunohistochemical analysis.We used quantitative reverse transcription polymerase chain reaction to analyze liver expression of inflammatory cytokines and chemokines.The cell lysates were subjected to immunoprecipitation with anti-Toll-IL-1R-containing adaptor inducing interferon-β(TRIF)and anti-myeloid differentiation factor 88(My D88),and then the immunoprecipitates were analyzed by SDS-PAGE and immunoblotted with the indicated antibodies.RESULTS:HO-1 protected livers from I/R injury,as evidenced by diminished liver enzymes and wellpreserved tissue architecture.In comparison with Zn PP livers 6 h after surgery,Co PP treatment livers showed a significant increase inflammatory cell infiltration of lymphocytes,plasma cells,neutrophils and macrophages.The Toll-like receptor(TLR)-4 and TANK binding kinase1 protein levels of rats treated with Co PP significantly reduced in TRIF-immunoprecipitated complex,as compared with Zn PP treatment.In addition,pretreatment with Co PP reduced the expression levels of TLR2,TLR4,IL-1R-associated kinase(IRAK)-1 and tumor necrosis factor receptor-associated factor 6 in My D88-immunoprecipitated complex.The inflammatory cytokines and chemokines m RNA expression rapidly decreased inCo PP-pretreated liver,compared with the Zn PP-treated group.However,the expression of negative regulators Tollinteracting protein,suppressor of cytokine signaling-1,IRAK-M and Src homology 2 domain-containing inositol-5-phosphatase-1 in Co PP treatment rats were markedly up-regulated as compared with Zn PP-treated rats.CONCLUSION:HO-1 protects liver against I/R injury by inhibiting TLR2/TLR4-triggered My D88-and TRIFdependent signaling pathways and increasing expression of negative regulators of TLR signaling in rats.展开更多
This study examined the ability of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (β-PGG) to induce the expression of heme oxygenase-1 (HO-1) in the PC12 cells and its regulation in the PC12 cells.One week before treatment w...This study examined the ability of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (β-PGG) to induce the expression of heme oxygenase-1 (HO-1) in the PC12 cells and its regulation in the PC12 cells.One week before treatment with the drug,nerve growth factor (NGF) was added to the cultures at a final concentration of 50 ng/mL to induce neuronal differentiation.After drug treatment,HO-1 gene transcription was analyzed by reverse transcription polymerase chain reaction (RT-PCR).Expression of HO-1 and NF-E2-related factor2 (Nrf2) and activation of extracellular signal-regulated kinase (ERK) and Akt were detected by Western blotting.The viability of the PC12 cells treated with different medicines was examined by MTT assay.The oxidative stress in the PC12 cells was evaluated qualitatively and quantitatively by DCFH-DA.The results showed that β-PGG up-regulated HO-1 expression and this increased expression provided neuroprotection against MPP+-induced oxidative injury.Moreover,β-PGG induced Nrf2 nuclear translocation,which was found to be upstream of β-PGG-induced HO-1 expression,and the activation of ERK and Akt,a pathway that is involved in β-PGG-induced Nrf2 nuclear translocation,HO-1 expression and neuroprotection.In conclusion,β-PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-and Akt-dependent manner,and HO-1 expression by β-PGG may provide the PC12 cells with an acquired antioxidant defense capacity to survive the oxidative stress.展开更多
Previous studies have demonstrated that sericin effectively reduces blood glucose, and protects islet cells, as well as the gonads and kidneys. However, whether sericin improves diabetes mellitus-induced structural an...Previous studies have demonstrated that sericin effectively reduces blood glucose, and protects islet cells, as well as the gonads and kidneys. However, whether sericin improves diabetes mellitus-induced structural and functional problems in the central nervous system remains poorly understood. Rat models of type 2 diabetes mellitus were established by intraperitoneal injection of streptozotocin. The present study observed histological changes in the hippocampus and cerebral cortex, as well as heme oxygenase-1 expression, and explored sericin effects on the central nervous system in diabetic rats. Pathological damage to neural cells in the rat hippocampus and cerebral cortex was relieved following intragastric administration of sericin at a dose of 2.4 g/kg for 35 consecutive days. Heme oxygenase-1 protein and mRNA expressions were decreased in the hippocampus and cerebral cortex of diabetes mellitus rats after sericin treatment. The results suggest that sericin plays a protective effect on the nervous system by decreasing the high expression of heme oxygenase-1 following diabetes mellitus.展开更多
Objective To assess the effect of atorvastatin on lipopolysaccharide （LPS）-induced TNF-a production in RAW264.7 macrophages. Methods RAW264.7 macrophages were treated in different LPS concentrations or at different ...Objective To assess the effect of atorvastatin on lipopolysaccharide （LPS）-induced TNF-a production in RAW264.7 macrophages. Methods RAW264.7 macrophages were treated in different LPS concentrations or at different time points with or without atorvastatin. TNF-a level in supernatant was measured. Expressions of TNF-a mRNA and protein and heme oxygenase-1 （HO-1） were detected by ELISA, PCR, and Western blot, respectively. HO activity was assayed. Results LPS significantly increased the TNF-a expression and secretion in a dose- and time-dependent manner. The HO-1 activity and HO-1 expression level were significantly higher after atorvastatin treatment than before atorvastatin treatment and attenuated by SB203580 and PD98059 but not by SP600125, suggesting that the ERK and p38 mitogen-activated protein kinase （MAPK） pathways participate in regulating the above-mentioned effects of atorvastatin. Moreover, the HO-1 activity suppressed by SnPP or the HO-1 expression inhibited by siRNA significantly attenuated the effect of atorvastatin on TNF-c~ expression and production in LPS-stimulated macrophages. Conclusion Atorvastatin can attenuate LPS-induced TNF-e expression and production by activating HO-1 via the ERK and p38 MAPK pathways, suggesting that atorvastatin can be used in treatment of inflammatory diseases such as sepsis, especially in those with atherosclerotic diseases.展开更多
BACKGROUND Sinapic acid(SA)has been shown to have various pharmacological properties such as antioxidant,antifibrotic,anti-inflammatory,and anticancer activities.Its mechanism of action is dependent upon its ability t...BACKGROUND Sinapic acid(SA)has been shown to have various pharmacological properties such as antioxidant,antifibrotic,anti-inflammatory,and anticancer activities.Its mechanism of action is dependent upon its ability to curb free radical production and protect against oxidative stress-induced tissue injuries.AIM To study the hepatoprotective effects of SA against lipopolysaccharide(LPS)/Dgalactosamine(D-GalN)-induced acute liver failure(ALF)in rats.METHODS Experimental ALF was induced with an intraperitoneal(i.p.)administration of 8μg LPS and 800 mg/kg D-GalN in normal saline.SA was administered orally once daily starting 7 d before LPS/D-GalN treatment.RESULTS Data showed that SA ameliorates acute liver dysfunction,decreases serum levels of alanine transaminase(ALT),and aspartate aminotransferase(AST),as well as malondialdehyde(MDA)and NO levels in ALF model rats.However,pretreatment with SA(20 mg/kg and 40 mg/kg)reduced nuclear factor kappalight-chain-enhancer of activated B cells(NF-κB)activation and levels of inflammatory cytokines(tumor necrosis factor-αand interleukin 6).Also,SA increased the activity of the nuclear factor erythroid-related factor 2/heme oxygenase-1(Nrf2/HO-1)signaling pathway.CONCLUSION In conclusion,SA offers significant protection against LPS/D-GalN-induced ALF in rats by upregulating Nrf2/HO-1 and downregulating NF-κB.展开更多
AIM: To examine the potency of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG) as a hepatic heme oxygen-ase-1(HO-1) inducer and its regulation in HepG2 cells. METHODS: Expression of HO-1 and NF-E2-related factor 2 (Nrf2)...AIM: To examine the potency of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG) as a hepatic heme oxygen-ase-1(HO-1) inducer and its regulation in HepG2 cells. METHODS: Expression of HO-1 and NF-E2-related factor 2 (Nrf2) and activation of mitogen-activated protein (MAP) kinases were analyzed by Western blot, immuno-fluorescence assay, and flow cytometry. Transfections of HO-1 gene, small interfering RNAs for HO-1 and Nrf2, and dominant-negative gene for MAP/extracellular signal-regulated kinase (ERK) were carried out to dissect the signaling pathways leading to HO-1 expression in HepG 2 cells. RESULTS: PGG up-regulated HO-1 expression and this expression conferred cytoprotection against oxidative injury induced by t-butyl hydroperoxide. Moreover, PGG induced Nrf2 nuclear translocation, which was found to be an upstream step of PGG-induced HO-1 expression, and ERK activation, of which pathway was involved in PGG-induced Nrf2 nuclear translocation, HO-1 expression and cytoprotection. CONCLUSION: PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-depen-dent manner, and HO-1 expression by PGG may serve as one of the important mechanisms for its hepatoprotective effects.展开更多
Opioids,such as morphine,are the most potent drugs used to treat pain.Long-term use results in high tolerance to morphine.High mobility group box-1(HMGB1) has been shown to participate in neuropathic or inflammatory p...Opioids,such as morphine,are the most potent drugs used to treat pain.Long-term use results in high tolerance to morphine.High mobility group box-1(HMGB1) has been shown to participate in neuropathic or inflammatory pain,but its role in morphine tolerance is unclear.In this study,we established rat and mouse models of morphine tolerance by intrathecal injection of morphine for 7 consecutive days.We found that morphine induced rat spinal cord neurons to release a large amount of HMGB1.HMGB1 regulated nuclear factor κB p65 phosphorylation and interleukin-1β production by increasing Toll-like receptor 4receptor expression in microglia,thereby inducing morphine tolerance.Glycyrrhizin,an HMGB1 inhibito r,markedly attenuated chronic morphine tole rance in the mouse model.Finally,compound C(adenosine 5’-monophosphate-activated protein kinase inhibitor) and zinc protoporphyrin(heme oxygenase-1 inhibitor)alleviated the morphine-induced release of HMGB1 and reduced nuclear factor κB p65 phosphorylation and interleukin-1β production in a mouse model of morphine tolerance and an SH-SY5Y cell model of morphine tole rance,and alleviated morphine tolerance in the mouse model.These findings suggest that morphine induces HMGB1 release via the adenosine 5’-monophosphate-activated protein kinase/heme oxygenase-1 signaling pathway,and that inhibiting this signaling pathway can effectively reduce morphine tole rance.展开更多
BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF...BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF-secreted toxin(BFT).Dendritic cells(DCs)play an important role in directing the nature of adaptive immune responses to bacterial infection and heme oxygenase-1(HO-1)is involved in the regulation of DC function.AIM To investigate the role of BFT in HO-1 expression in DCs.METHODS Murine DCs were generated from specific pathogen-free C57BL/6 and Nrf2−/−knockout mice.DCs were exposed to BFT,after which HO-1 expression and the related signaling factor activation were measured by quantitative RT-PCR,EMSA,fluorescent microscopy,immunoblot,and ELISA.RESULTS HO-1 expression was upregulated in DCs stimulated with BFT.Although BFT activated transcription factors such as NF-κB,AP-1,and Nrf2,activation of NF-κB and AP-1 was not involved in the induction of HO-1 expression in BFT-exposed DCs.Instead,upregulation of HO-1 expression was dependent on Nrf2 activation in DCs.Moreover,HO-1 expression via Nrf2 in DCs was regulated by mitogenactivated protein kinases such as ERK and p38.Furthermore,BFT enhanced the production of reactive oxygen species(ROS)and inhibition of ROS production resulted in a significant decrease of phospho-ERK,phospho-p38,Nrf2,and HO-1 CONCLUSION These results suggest that signaling pathways involving ROS-mediated ERK and p38 mitogen-activated protein kinases-Nrf2 activation in DCs are required for HO-1 induction during exposure to ETBF-produced BFT.展开更多
文摘Summary: In order to investigate the relationship between the expression of heme oxygenase-2 (HO-2) mRNA and the pathogenesis of Hirschsprung's disease (HD), total ribonucleic acid (RNA) was extracted in the aganglionic and ganglionic segments of colon respectively from 15 cases of HD. The single-stranded cDNA of HO-2 was synthesized and further amplified by reverse transcription-polymerase chain reaction (RT-PCR). The expression of HO-2 mRNA was normal in ganglionic segments, but absent in aganglionic segments. It is concluded that the absence of HO-2 mRNA expression may be an important mechanism responsible for HD.
基金supported by grants from Jiangsu Commission of Health,No.Z2021086(to XL)Science and Technology Program of Suzhou,Nos.SYSD2020008(to XL),SKYD2022012(to XL)+1 种基金Suzhou Municipal Health Commission,No.KJXW2020058(to XL)Science and Technology Program of Zhangjiagang,No.ZKS2018(to XL)。
文摘Interfering with the ferroptosis pathway is a new strategy for the treatment of spinal cord injury.Fibroblast growth factor 21 can inhibit ferro ptosis and promote neurofunctional recovery,while heme oxygenase-1 is a regulator of iron and reactive oxygen species homeostasis.The relationship between heme oxygenase-1and ferroptosis remains controve rsial.In this study,we used a spinal co rd injury rat model to show that the levels of fibroblast growth factor 21 in spinal co rd tissue decreased after spinal cord injury.In addition,there was a significant aggravation of ferroptosis and a rapid increase in heme oxygenase-1 expression after spinal cord injury.Furthe r,heme oxygenase-1 aggravated fe rroptosis after spinal cord injury,while fibroblast growth factor 21 inhibited fe rroptosis by downregulating heme oxygenase-1.Thus,the activation of fibroblast growth factor 21 may provide a potential treatment for spinal co rd injury.These findings could provide a new potential mechanistic explanation for fibroblast growth factor 21 in the treatment of spinal cord injury.
文摘Previous studies have reported upregulation of heme oxygenase-1 in different central nervous system injury models.Heme oxygenase-1 plays a critical anti-inflammatory role and is essential for regulating cellular redox homeostasis.Metformin is a classic drug used to treat type 2 diabetes that can inhibit ferroptosis.Previous studies have shown that,when used to treat cardiovascular and digestive system diseases,metformin can also upregulate heme oxygenase-1 expression.Therefore,we hypothesized that heme oxygenase-1 plays a significant role in mediating the beneficial effects of metformin on neuronal ferroptosis after spinal cord injury.To test this,we first performed a bioinformatics analysis based on the GEO database and found that heme oxygenase-1 was upregulated in the lesion of rats with spinal cord injury.Next,we confirmed this finding in a rat model of T9 spinal cord compression injury that exhibited spinal cord nerve cell ferroptosis.Continuous intraperitoneal injection of metformin for 14 days was found to both upregulate heme oxygenase-1 expression and reduce neuronal ferroptosis in rats with spinal cord injury.Subsequently,we used a lentivirus vector to knock down heme oxygenase-1 expression in the spinal cord,and found that this significantly reduced the effect of metformin on ferroptosis after spinal cord injury.Taken together,these findings suggest that metformin inhibits neuronal ferroptosis after spinal cord injury,and that this effect is partially dependent on upregulation of heme oxygenase-1.
基金Supported by National Natural Science Foundation of China,No.81360079Yunnan Provincial Science and Technology Department and Kunming Medical University Collaborative Fund,No.2013FB142
文摘AIM:To investigate the efficacy and molecularmechanisms of induced heme oxygenase(HO)-1 in protecting liver from warm ischemia/reperfusion(I/R)injury.METHODS:Partial warm ischemia was produced in the left and middle hepatic lobes of SD rats for 75min,followed by 6 h of reperfusion.Rats were treated with saline,cobalt protoporphyrin(Co PP)or zinc protoporphyrin(Zn PP)at 24 h prior to the ischemia insult.Blood and samples of ischemic lobes subjected to ischemia were collected at 6 h after reperfusion.Serum transaminases level,plasma lactate dehydrogenase and myeloperoxidase activity in liver were measured.Liver histological injury and inflammatory cell infiltration were evaluated by tissue section and liver immunohistochemical analysis.We used quantitative reverse transcription polymerase chain reaction to analyze liver expression of inflammatory cytokines and chemokines.The cell lysates were subjected to immunoprecipitation with anti-Toll-IL-1R-containing adaptor inducing interferon-β(TRIF)and anti-myeloid differentiation factor 88(My D88),and then the immunoprecipitates were analyzed by SDS-PAGE and immunoblotted with the indicated antibodies.RESULTS:HO-1 protected livers from I/R injury,as evidenced by diminished liver enzymes and wellpreserved tissue architecture.In comparison with Zn PP livers 6 h after surgery,Co PP treatment livers showed a significant increase inflammatory cell infiltration of lymphocytes,plasma cells,neutrophils and macrophages.The Toll-like receptor(TLR)-4 and TANK binding kinase1 protein levels of rats treated with Co PP significantly reduced in TRIF-immunoprecipitated complex,as compared with Zn PP treatment.In addition,pretreatment with Co PP reduced the expression levels of TLR2,TLR4,IL-1R-associated kinase(IRAK)-1 and tumor necrosis factor receptor-associated factor 6 in My D88-immunoprecipitated complex.The inflammatory cytokines and chemokines m RNA expression rapidly decreased inCo PP-pretreated liver,compared with the Zn PP-treated group.However,the expression of negative regulators Tollinteracting protein,suppressor of cytokine signaling-1,IRAK-M and Src homology 2 domain-containing inositol-5-phosphatase-1 in Co PP treatment rats were markedly up-regulated as compared with Zn PP-treated rats.CONCLUSION:HO-1 protects liver against I/R injury by inhibiting TLR2/TLR4-triggered My D88-and TRIFdependent signaling pathways and increasing expression of negative regulators of TLR signaling in rats.
基金supported by National 11th Five-Year Plan Research Foundation of China (No.2006BAI01A14)
文摘This study examined the ability of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (β-PGG) to induce the expression of heme oxygenase-1 (HO-1) in the PC12 cells and its regulation in the PC12 cells.One week before treatment with the drug,nerve growth factor (NGF) was added to the cultures at a final concentration of 50 ng/mL to induce neuronal differentiation.After drug treatment,HO-1 gene transcription was analyzed by reverse transcription polymerase chain reaction (RT-PCR).Expression of HO-1 and NF-E2-related factor2 (Nrf2) and activation of extracellular signal-regulated kinase (ERK) and Akt were detected by Western blotting.The viability of the PC12 cells treated with different medicines was examined by MTT assay.The oxidative stress in the PC12 cells was evaluated qualitatively and quantitatively by DCFH-DA.The results showed that β-PGG up-regulated HO-1 expression and this increased expression provided neuroprotection against MPP+-induced oxidative injury.Moreover,β-PGG induced Nrf2 nuclear translocation,which was found to be upstream of β-PGG-induced HO-1 expression,and the activation of ERK and Akt,a pathway that is involved in β-PGG-induced Nrf2 nuclear translocation,HO-1 expression and neuroprotection.In conclusion,β-PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-and Akt-dependent manner,and HO-1 expression by β-PGG may provide the PC12 cells with an acquired antioxidant defense capacity to survive the oxidative stress.
基金supported by the Grant of Department of Education of Hebei Province (GH/IGF-1 action mechanism in diabetes mellitus-induced gonadal axis injury and protective effects of sericin),No.2006301the Grant of the Department of Technology of Hebei Province (Protective effects of sericin on testicular dysfunction following diabetes mellitus),No.08276101D-19
文摘Previous studies have demonstrated that sericin effectively reduces blood glucose, and protects islet cells, as well as the gonads and kidneys. However, whether sericin improves diabetes mellitus-induced structural and functional problems in the central nervous system remains poorly understood. Rat models of type 2 diabetes mellitus were established by intraperitoneal injection of streptozotocin. The present study observed histological changes in the hippocampus and cerebral cortex, as well as heme oxygenase-1 expression, and explored sericin effects on the central nervous system in diabetic rats. Pathological damage to neural cells in the rat hippocampus and cerebral cortex was relieved following intragastric administration of sericin at a dose of 2.4 g/kg for 35 consecutive days. Heme oxygenase-1 protein and mRNA expressions were decreased in the hippocampus and cerebral cortex of diabetes mellitus rats after sericin treatment. The results suggest that sericin plays a protective effect on the nervous system by decreasing the high expression of heme oxygenase-1 following diabetes mellitus.
基金supported by National Natural Science Foundation of China(No.81270212)Natural Science Foundation of Guangdong Province(S2013010014011)Young Teacher Key Support Project by Sun Yat-Sen University
文摘Objective To assess the effect of atorvastatin on lipopolysaccharide （LPS）-induced TNF-a production in RAW264.7 macrophages. Methods RAW264.7 macrophages were treated in different LPS concentrations or at different time points with or without atorvastatin. TNF-a level in supernatant was measured. Expressions of TNF-a mRNA and protein and heme oxygenase-1 （HO-1） were detected by ELISA, PCR, and Western blot, respectively. HO activity was assayed. Results LPS significantly increased the TNF-a expression and secretion in a dose- and time-dependent manner. The HO-1 activity and HO-1 expression level were significantly higher after atorvastatin treatment than before atorvastatin treatment and attenuated by SB203580 and PD98059 but not by SP600125, suggesting that the ERK and p38 mitogen-activated protein kinase （MAPK） pathways participate in regulating the above-mentioned effects of atorvastatin. Moreover, the HO-1 activity suppressed by SnPP or the HO-1 expression inhibited by siRNA significantly attenuated the effect of atorvastatin on TNF-c~ expression and production in LPS-stimulated macrophages. Conclusion Atorvastatin can attenuate LPS-induced TNF-e expression and production by activating HO-1 via the ERK and p38 MAPK pathways, suggesting that atorvastatin can be used in treatment of inflammatory diseases such as sepsis, especially in those with atherosclerotic diseases.
基金Deanship of Scientific Research at King Saud University,No.RG-1439-083.
文摘BACKGROUND Sinapic acid(SA)has been shown to have various pharmacological properties such as antioxidant,antifibrotic,anti-inflammatory,and anticancer activities.Its mechanism of action is dependent upon its ability to curb free radical production and protect against oxidative stress-induced tissue injuries.AIM To study the hepatoprotective effects of SA against lipopolysaccharide(LPS)/Dgalactosamine(D-GalN)-induced acute liver failure(ALF)in rats.METHODS Experimental ALF was induced with an intraperitoneal(i.p.)administration of 8μg LPS and 800 mg/kg D-GalN in normal saline.SA was administered orally once daily starting 7 d before LPS/D-GalN treatment.RESULTS Data showed that SA ameliorates acute liver dysfunction,decreases serum levels of alanine transaminase(ALT),and aspartate aminotransferase(AST),as well as malondialdehyde(MDA)and NO levels in ALF model rats.However,pretreatment with SA(20 mg/kg and 40 mg/kg)reduced nuclear factor kappalight-chain-enhancer of activated B cells(NF-κB)activation and levels of inflammatory cytokines(tumor necrosis factor-αand interleukin 6).Also,SA increased the activity of the nuclear factor erythroid-related factor 2/heme oxygenase-1(Nrf2/HO-1)signaling pathway.CONCLUSION In conclusion,SA offers significant protection against LPS/D-GalN-induced ALF in rats by upregulating Nrf2/HO-1 and downregulating NF-κB.
基金Supported by the Korean Research Foundation Grant(KRF-2004-005-200038)
文摘AIM: To examine the potency of 1,2,3,4,6-penta-O-galloyl-β-D-glucose (PGG) as a hepatic heme oxygen-ase-1(HO-1) inducer and its regulation in HepG2 cells. METHODS: Expression of HO-1 and NF-E2-related factor 2 (Nrf2) and activation of mitogen-activated protein (MAP) kinases were analyzed by Western blot, immuno-fluorescence assay, and flow cytometry. Transfections of HO-1 gene, small interfering RNAs for HO-1 and Nrf2, and dominant-negative gene for MAP/extracellular signal-regulated kinase (ERK) were carried out to dissect the signaling pathways leading to HO-1 expression in HepG 2 cells. RESULTS: PGG up-regulated HO-1 expression and this expression conferred cytoprotection against oxidative injury induced by t-butyl hydroperoxide. Moreover, PGG induced Nrf2 nuclear translocation, which was found to be an upstream step of PGG-induced HO-1 expression, and ERK activation, of which pathway was involved in PGG-induced Nrf2 nuclear translocation, HO-1 expression and cytoprotection. CONCLUSION: PGG up-regulates HO-1 expression by stimulating Nrf2 nuclear translocation in an ERK-depen-dent manner, and HO-1 expression by PGG may serve as one of the important mechanisms for its hepatoprotective effects.
基金supported by the National Natural Science Foundation of ChinaNos.81971047 (to WTL) and 82073910 (to XFW)+2 种基金the Natural Science Foundation of Jiangsu Province,No.BK20191253 (to XFW)Key R&D Program (Social Development) Project of Jiangsu Province,No.BE2019 732 (to WTL)Jiangsu Province Hospital (the First Affiliated Hospital of Nanjing Medical University) Clinical Capacity Enhancement Project,No.JSPH-511B2018-8 (to YBP)。
文摘Opioids,such as morphine,are the most potent drugs used to treat pain.Long-term use results in high tolerance to morphine.High mobility group box-1(HMGB1) has been shown to participate in neuropathic or inflammatory pain,but its role in morphine tolerance is unclear.In this study,we established rat and mouse models of morphine tolerance by intrathecal injection of morphine for 7 consecutive days.We found that morphine induced rat spinal cord neurons to release a large amount of HMGB1.HMGB1 regulated nuclear factor κB p65 phosphorylation and interleukin-1β production by increasing Toll-like receptor 4receptor expression in microglia,thereby inducing morphine tolerance.Glycyrrhizin,an HMGB1 inhibito r,markedly attenuated chronic morphine tole rance in the mouse model.Finally,compound C(adenosine 5’-monophosphate-activated protein kinase inhibitor) and zinc protoporphyrin(heme oxygenase-1 inhibitor)alleviated the morphine-induced release of HMGB1 and reduced nuclear factor κB p65 phosphorylation and interleukin-1β production in a mouse model of morphine tolerance and an SH-SY5Y cell model of morphine tole rance,and alleviated morphine tolerance in the mouse model.These findings suggest that morphine induces HMGB1 release via the adenosine 5’-monophosphate-activated protein kinase/heme oxygenase-1 signaling pathway,and that inhibiting this signaling pathway can effectively reduce morphine tole rance.
基金Supported by the Basic Science Research Program through the National Research Foundation of Korea funded by the Ministry of Education,Science and Technology,South Korea,No.NRF-2018R1D1A1B07043350
文摘BACKGROUND Enterotoxigenic Bacteroides fragilis(ETBF)causes colitis and diarrhea,and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers.These diseases are dependent on ETBF-secreted toxin(BFT).Dendritic cells(DCs)play an important role in directing the nature of adaptive immune responses to bacterial infection and heme oxygenase-1(HO-1)is involved in the regulation of DC function.AIM To investigate the role of BFT in HO-1 expression in DCs.METHODS Murine DCs were generated from specific pathogen-free C57BL/6 and Nrf2−/−knockout mice.DCs were exposed to BFT,after which HO-1 expression and the related signaling factor activation were measured by quantitative RT-PCR,EMSA,fluorescent microscopy,immunoblot,and ELISA.RESULTS HO-1 expression was upregulated in DCs stimulated with BFT.Although BFT activated transcription factors such as NF-κB,AP-1,and Nrf2,activation of NF-κB and AP-1 was not involved in the induction of HO-1 expression in BFT-exposed DCs.Instead,upregulation of HO-1 expression was dependent on Nrf2 activation in DCs.Moreover,HO-1 expression via Nrf2 in DCs was regulated by mitogenactivated protein kinases such as ERK and p38.Furthermore,BFT enhanced the production of reactive oxygen species(ROS)and inhibition of ROS production resulted in a significant decrease of phospho-ERK,phospho-p38,Nrf2,and HO-1 CONCLUSION These results suggest that signaling pathways involving ROS-mediated ERK and p38 mitogen-activated protein kinases-Nrf2 activation in DCs are required for HO-1 induction during exposure to ETBF-produced BFT.
