The input-output relationship of neuronal networks depends heavily on the intrinsic properties of their neuronal elements.Profound changes in intrinsic properties have been observed in various physiological and pathol...The input-output relationship of neuronal networks depends heavily on the intrinsic properties of their neuronal elements.Profound changes in intrinsic properties have been observed in various physiological and pathological processes,such as learning,memory and epilepsy.However,the cellular and molecular mechanisms underlying acquired changes in intrinsic excitability are still not fully understood.Here,we demonstrate that ERG3 channels are critically involved in the regulation of intrinsic excitability in hippocampal CA1 pyramidal neurons and DG granule cells.Knock-down of ERG3 channels significantly increases neuronal intrinsic excitability,which is mainly caused by decreased fast afterhyperpolarization,delayed time to the generation of an action potential and enhanced summation of somatic excitatory post-synaptic potentials.Interestingly,the expression level of ERG3 protein is significantly reduced in human and mouse brain tissues with temporal lobe epilepsy.Moreover,ERG3 channel knock-down in hippocampus significantly enhanced seizure susceptibility,while mice treated with ERG3 channel activator NS1643 were less prone to epileptogenesis.Taken together,our results suggest ERG3 channels play an important role in determining the excitability of hippocampal neurons and dysregulation of these channels may be involved in the generation of epilepsy.ERG3 channels may thus be a novel therapeutic target for the prevention of epilepsy.展开更多
OBJECTIVE Diabetes-induced endothelial cell(EC) dysfunction and neovasculariza.tion impairment constitute vascular complications with limited treatment regimens.Transcription factor FOXO1 is a key angiogenic regulator...OBJECTIVE Diabetes-induced endothelial cell(EC) dysfunction and neovasculariza.tion impairment constitute vascular complications with limited treatment regimens.Transcription factor FOXO1 is a key angiogenic regulator and plays a pathologic role in progression of diabetes.The pres.ent study was designed to determine the involvement of FOXO1 in impaired EC function and post-isch.emic neovascularization in diabetes and investigate underlying mechanisms.RESULTS We found that FOXO1-selective inhibitor AS1842856 improved blood flow recovery and capillary density in ischemic hindlimb,and rescued the delay of wound closure with a concomitant augmentation of mean perfusion rate in diabetic mice.In vitro,treatment with AS1842856 or FOXO1 siRNA abrogated high glucose-in.duced apoptosis and ameliorated capillary tube formation in human umbilical vein endothelial cells(HU.VECs).FOXO1 inhibition relieved alterations in mitochondrial networks and significantly suppressed the over production of mitochondrial reactive oxygen species(mtROS) induced by high glucose in ECs.Expression of dynamin-relatedprotein-1(Drp1) and phosphorylation at Ser616,a protein required for mitochondrial fission,were enhanced by hyperglycemia,which could be neutralized by FOXO1 inhibition.Moreover,the transcription of Rho-associated coiled-coil containing protein kinase 1(ROCK1),which phosphorylates Drp1 at Ser616,was shown by luciferase assay to be directly regulated by FOXO1.CONCLUSION These findings suggested that FOXO1 is critical to preserve mitochondrial quantity and func.tion in ECs,and FOXO1 may serve as a therapeutic target for microvascular complications of diabetes.展开更多
OBJECTIVE Compound Kushen injection(CKI)is a bis-herbal formulation extracted from Kushen(Radix Sophorae Flavescentis)and Baituling(Rhizoma Heterosmilacis Japonicae).Clinically,it is used as the adjuvant treatment of ...OBJECTIVE Compound Kushen injection(CKI)is a bis-herbal formulation extracted from Kushen(Radix Sophorae Flavescentis)and Baituling(Rhizoma Heterosmilacis Japonicae).Clinically,it is used as the adjuvant treatment of cancer.However,with the increased application,the cases of immediate hypersensitivity reactions(IHRs)also gradually rise.In this study,we investigated the underlying mechanism(s)and active constituent(s)for CKI-induced IHRs in experimental models.METHODS T helper 2(Th2)immunity-amplified mice were prepared by aluminum adjuvant.Anaphylactic shock was detected by measuring rectal thermometry in propranolol pretreated mice.For evaluating microvascular permeability,Evans blue extravasation assay was used.Platelet-activating factor(PAF),serum total IgE(tIgE)and mouse mast cell protease 1(MMCP1)were measured by ELISA.RESULTS The obtained results showed that CKI did not elevate serum tIgE and MMCP1 after consecutive immunization for five weeks,but could induce Evans blue extravasation(local)and cause obvious hypothermia(systemic)after a single injection.Further study showed that alkaloids in Kushen,especially matrine,were responsible for CKI-induced IHRs.Mechanism study showed that various PAF receptor antagonists could significantly counter CKI-induced IHRs locally or systemically.In cell system,CKI was able to promote PAF production in a non-cell-selective manner.In cell lysate,the effect of CKI on PAF production became stronger and could be abolished by blocking de novo pathway.CONCLUSION In conclusion,our study identifies,for the first time,that CKI is a PAF inducer.It causes non-immunologic IHRs,rather than IgE-dependent IHRs,by promoting PAF production through de novo pathway.Alkaloids in Kushen,especially matrine,are the prime culprits for IHRs.Our findings may provide a potential approach for preventing and treating CKI-induced IHRs.展开更多
OBJECTIVE Non-alcoholic fatty liver disease(NAFLD) encompasses a series of patho.logic changes ranging from steatosis to steatohepatitis,which may progress to cirrhosis and hepatocel.lular carcinoma.The purpose of thi...OBJECTIVE Non-alcoholic fatty liver disease(NAFLD) encompasses a series of patho.logic changes ranging from steatosis to steatohepatitis,which may progress to cirrhosis and hepatocel.lular carcinoma.The purpose of this study was to determine whether Ganoderma lucidum polysaccha.ride peptide(GLPP) has therapeutic effect on NAFLD.METHODS ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic path.ways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophospholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7 A1,CYP8 B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1 c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepato.cytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a therapeutic drug for NAFLD.展开更多
Gefitinib is widely used for the treatment of lung cancer in patients with sensitizing epidermal growth factor receptor mutations,but patients tend to develop resistance after an average of 10 months.Low molecular wei...Gefitinib is widely used for the treatment of lung cancer in patients with sensitizing epidermal growth factor receptor mutations,but patients tend to develop resistance after an average of 10 months.Low molecular weight heparins,such as enoxaparin,potently inhibit experimental metastasis.This study aimed to determine the potential of combined enoxaparin and gefitinib(enoxaparin+gefitinib)treatment to inhibit tumor resistance to gefitinib both in vitro and in vivo.A549 and H1975 cell migration was analyzed in wound closure and Transwell assays.Akt and extracellular signal related kinase 1/2(Erk1/2)signaling pathways were identified,and a proteomics analysis was conducted using SDSPAGE/liquid chromatography-tandem mass spectrometry analysis.Molecular interaction networks were visualized using the cytoscape bioinformatics platform.Protein expression of dedicator of cytokinesis1(DOCK1)and cytoskeleton intermediate filament vimentin were identified using an enzyme-linked immunosorbent assay,Western blotting,and small interfering RNA transfection of A549 cells.In xenograft A549-luc-C8 tumors in nude mice,enoxaparin+gefitinib inhibited tumor growth and reduced lung colony formation compared with gefitinib alone.Furthermore,the combination had stronger inhibitory effects on cell migration than either agent used individually.Additional enoxaparin administration resulted in better effective inhibition of Akt activity compared with gefitinib alone.Proteomics and network analysis implicated DOCK1 as the key node molecule.Western blot verified the effective inhibition of the expression of DOCK1 and vimentin phosphorylation by enoxaparin+gefitinib comparedwith gefitinib alone.DOCK1 knockdown confirmed its role in cell migration,Akt expression,and vimentin phosphorylation.Our data indicate that enoxaparin sensitizes gefitinib antitumor and antimigration activity in lung cancer by suppressing DOCK1 expression,Akt activity,and vimentin phosphorylation.展开更多
Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration ...Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Iα-loop-helix Iβmotif which corresponds to helix I of other P 450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,theγ-domain.The structure reveals a homodimer in which theγ-domain of one molecule interacts with theβ-domain of another.The plane of heme group makes an angle of approximately 40°with the helix Iα-loop-helix Iβmotif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recognition.Phe-301,Ser-303 and Gly-305 from the helix Iα-loop-helix Iβmotif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.展开更多
OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to ...OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to determine whether GLPP could attenuate RIRI via counteracting the oxidative stress.METHODS Mice subjected to uninephrectomy with the right kidney ischemia for 35 min and reperfusion for 24 hwere used to explore the protective activity of GLPP against RIRI.In GLPP-treated group,100mg·kg-1·d-1 of GLPP were intraperitoneally injected for 7dbefore the procedure.In vitro,NRK-52 Ecells subjected to hypoxia-reoxygenation(H/R)and tunicamycin were used to explore the protective effect of GLPP against oxidative stress.The mechanisms in which GLPP protected kidney from RIRI were studied using a series of physiological and molecular biological methods.RESULTS Kidneys undergone ischemia-reperfusion showed renal dysfunction and characteristic morphological changes including cellular necrosis,brush border loss,cast formation,vacuolization and tubular dilatation while these damages were significantly attenuated by GLPP treatment.The abnormal levels of MPO,MDA and SOD caused by renal ischemia-reperfusion were significantly reversed by GLPP treatment.More apoptotic cells were found in the renal ischemia-reperfusion group than the sham group whereas GLPP reduced apoptotic cells in the ischemia-reperfusion mice by21.75%(P<0.01).The GLPPs(25-1μg·mL)alleviated H/R induced cell viability loss by 20.12%(P<0.01)andΔφm dissipation by 27.3%(P<0.01)in vitro as well and its pretreatment dramatically reduced H/R and tunicamycin induced cell injury.CONCLUSION Our study found that GLPP had a protective effect on RIRI via its anti-oxidative capacity,which suggests that GLPP may be developed as a candidate drug for preventing acute kidney injury.展开更多
OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%....OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%.The purpose of this study was to determine whether GLPP has therapeutic effect on Non-alcoholic fatty liver disease(NAFLD).METHODS Ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic pathways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophos⁃pholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7A1,CYP8B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepatocytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a ther⁃apeutic drug for NAFLD.展开更多
OBJECTIVE Our group mainly focuses on the target identification and pharmacological mechanism study of TCM.We deeply identified the direct targets of the active ingredients in TCM using molecule probe-'Target Fish...OBJECTIVE Our group mainly focuses on the target identification and pharmacological mechanism study of TCM.We deeply identified the direct targets of the active ingredients in TCM using molecule probe-'Target Fishing' technology in chemical biology,and explored the related signaling pathways to explain the traditional efficiency of TCM.METHODS We synthesized biotin-tagged mole.cule probe by connecting biotin tag to TCM active molecule using PGE as a linker.Then,the biotintagged molecule probe was bound to the surface of solid beads by strong biotin-avidin interaction.Thus,the molecule probe-bound beads were mixed with cell lysates to capture the potential targets and identified by MS.RESULTS Our study found that SA which was an anti-inflammatory compound.could selectively bind to IMPDH2 in microglial cells,and SA showed weaker anti-inflammatory effect on IMPDH2-knock down microglial cells,suggesting IMPDH2 as a key anti-inflammatory target for SA.Ad.ditionally,handelin was a key anti-inflammatory compound.We identified the target protein of handelin as Hsp70 from microglial cells using target pull-down technology.Moreover,handelin showed weaker anti-inflammatory effect on Hsp70-knock down microglial cells,revealing that Hsp70 was the direct antiinflammatory target of handelin.CONCLUSION Our study provided methodology references for TCM target identification in the future,and also showed a new insight for exploring the pharmacological mechanism of TCM active ingredients.More importantly,we can perform scientific annotation for TCM efficiency by clarifying the biological functions of each target protein,showing important significance on modernization and internationalization of TCM.展开更多
OBJECTIVE Autosomal dominant polycystic kidney disease(ADPKD)is a common inherited disease with a high morbidity around 1/1000-1/400,characterized by progressive enlargement of fluid-fil ed cysts derived from renal tu...OBJECTIVE Autosomal dominant polycystic kidney disease(ADPKD)is a common inherited disease with a high morbidity around 1/1000-1/400,characterized by progressive enlargement of fluid-fil ed cysts derived from renal tubular epithelial cells.Massive cysts gradually compress renal parenchyma destroying normal renal structures and compromising renal functions.Unfortunately,it will cause end-stage renal disease in most of the patients but without effective therapy now,who have to live on hemodialysis or kidney transplantation.Based on this present situation,it is of great significance to find early intervention to inhibit renal cyst development.The projective of this study was to investigate whether Ganoderma triterpenes(GT)can inhibit renal cyst development and study the related mechanism.METHODS and RESULTS First,we used MDCK cyst model,cultivated MDCK cells in vitro to form fluid-filled cysts surrounded by monolayer cells.GT inhibited MDCK cyst formation significantly,and inhibited cyst enlargement dose-dependently proving GT cyst inhibition in vitro.Then we used an embryonic kidney cyst model,wile-type mice kidneys were taken out on embryonic day 13.5 to form renal cysts stimulated with 8-Br-c AMP.GT inhibited embryonic kidney cyst development significantly in a dosedependent and reversible manner proving GT cyst inhibition at organ level.Furthermore,we used two ADPKD mouse models with severe cystic kidney disease phenotypes.GT dramatically inhibited renal cyst development,decreased ADPKD mouse kidney volume and the cyst index inside proving GT cyst inhibition in vivo.By Western blot,we proved GT down-regulated Ras/MAPK signal pathway without detectable effect on m TOR signal pathway both in MDCK cells and two ADPKD mouse kidneys.CONCLUSION GT retard renal cyst development both in vitro and in vivo significantly.The related mechanisms were involved in GT promoting renal tubular epithelial cell differentiation,down-regulating intracellular c AMP level and Ras/MAPK signal pathway.展开更多
文摘The input-output relationship of neuronal networks depends heavily on the intrinsic properties of their neuronal elements.Profound changes in intrinsic properties have been observed in various physiological and pathological processes,such as learning,memory and epilepsy.However,the cellular and molecular mechanisms underlying acquired changes in intrinsic excitability are still not fully understood.Here,we demonstrate that ERG3 channels are critically involved in the regulation of intrinsic excitability in hippocampal CA1 pyramidal neurons and DG granule cells.Knock-down of ERG3 channels significantly increases neuronal intrinsic excitability,which is mainly caused by decreased fast afterhyperpolarization,delayed time to the generation of an action potential and enhanced summation of somatic excitatory post-synaptic potentials.Interestingly,the expression level of ERG3 protein is significantly reduced in human and mouse brain tissues with temporal lobe epilepsy.Moreover,ERG3 channel knock-down in hippocampus significantly enhanced seizure susceptibility,while mice treated with ERG3 channel activator NS1643 were less prone to epileptogenesis.Taken together,our results suggest ERG3 channels play an important role in determining the excitability of hippocampal neurons and dysregulation of these channels may be involved in the generation of epilepsy.ERG3 channels may thus be a novel therapeutic target for the prevention of epilepsy.
基金supported by National Natural Science Foundation of China(8167348681373405a+3 种基金30901803) Beijing Natural Science Foundation(7172119) Beijing Higher Education Young Elite Teacher Project(YETP0053) Beijing Golden Bridge Seed Capital Project(ZZ16019)
文摘OBJECTIVE Diabetes-induced endothelial cell(EC) dysfunction and neovasculariza.tion impairment constitute vascular complications with limited treatment regimens.Transcription factor FOXO1 is a key angiogenic regulator and plays a pathologic role in progression of diabetes.The pres.ent study was designed to determine the involvement of FOXO1 in impaired EC function and post-isch.emic neovascularization in diabetes and investigate underlying mechanisms.RESULTS We found that FOXO1-selective inhibitor AS1842856 improved blood flow recovery and capillary density in ischemic hindlimb,and rescued the delay of wound closure with a concomitant augmentation of mean perfusion rate in diabetic mice.In vitro,treatment with AS1842856 or FOXO1 siRNA abrogated high glucose-in.duced apoptosis and ameliorated capillary tube formation in human umbilical vein endothelial cells(HU.VECs).FOXO1 inhibition relieved alterations in mitochondrial networks and significantly suppressed the over production of mitochondrial reactive oxygen species(mtROS) induced by high glucose in ECs.Expression of dynamin-relatedprotein-1(Drp1) and phosphorylation at Ser616,a protein required for mitochondrial fission,were enhanced by hyperglycemia,which could be neutralized by FOXO1 inhibition.Moreover,the transcription of Rho-associated coiled-coil containing protein kinase 1(ROCK1),which phosphorylates Drp1 at Ser616,was shown by luciferase assay to be directly regulated by FOXO1.CONCLUSION These findings suggested that FOXO1 is critical to preserve mitochondrial quantity and func.tion in ECs,and FOXO1 may serve as a therapeutic target for microvascular complications of diabetes.
文摘OBJECTIVE Compound Kushen injection(CKI)is a bis-herbal formulation extracted from Kushen(Radix Sophorae Flavescentis)and Baituling(Rhizoma Heterosmilacis Japonicae).Clinically,it is used as the adjuvant treatment of cancer.However,with the increased application,the cases of immediate hypersensitivity reactions(IHRs)also gradually rise.In this study,we investigated the underlying mechanism(s)and active constituent(s)for CKI-induced IHRs in experimental models.METHODS T helper 2(Th2)immunity-amplified mice were prepared by aluminum adjuvant.Anaphylactic shock was detected by measuring rectal thermometry in propranolol pretreated mice.For evaluating microvascular permeability,Evans blue extravasation assay was used.Platelet-activating factor(PAF),serum total IgE(tIgE)and mouse mast cell protease 1(MMCP1)were measured by ELISA.RESULTS The obtained results showed that CKI did not elevate serum tIgE and MMCP1 after consecutive immunization for five weeks,but could induce Evans blue extravasation(local)and cause obvious hypothermia(systemic)after a single injection.Further study showed that alkaloids in Kushen,especially matrine,were responsible for CKI-induced IHRs.Mechanism study showed that various PAF receptor antagonists could significantly counter CKI-induced IHRs locally or systemically.In cell system,CKI was able to promote PAF production in a non-cell-selective manner.In cell lysate,the effect of CKI on PAF production became stronger and could be abolished by blocking de novo pathway.CONCLUSION In conclusion,our study identifies,for the first time,that CKI is a PAF inducer.It causes non-immunologic IHRs,rather than IgE-dependent IHRs,by promoting PAF production through de novo pathway.Alkaloids in Kushen,especially matrine,are the prime culprits for IHRs.Our findings may provide a potential approach for preventing and treating CKI-induced IHRs.
基金supported by National Natural Science Foundation of China(8133007481620108029+1 种基金81261160507) Beijing Natural Science Foundation(7172113)
文摘OBJECTIVE Non-alcoholic fatty liver disease(NAFLD) encompasses a series of patho.logic changes ranging from steatosis to steatohepatitis,which may progress to cirrhosis and hepatocel.lular carcinoma.The purpose of this study was to determine whether Ganoderma lucidum polysaccha.ride peptide(GLPP) has therapeutic effect on NAFLD.METHODS ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic path.ways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophospholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7 A1,CYP8 B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1 c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepato.cytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a therapeutic drug for NAFLD.
文摘Gefitinib is widely used for the treatment of lung cancer in patients with sensitizing epidermal growth factor receptor mutations,but patients tend to develop resistance after an average of 10 months.Low molecular weight heparins,such as enoxaparin,potently inhibit experimental metastasis.This study aimed to determine the potential of combined enoxaparin and gefitinib(enoxaparin+gefitinib)treatment to inhibit tumor resistance to gefitinib both in vitro and in vivo.A549 and H1975 cell migration was analyzed in wound closure and Transwell assays.Akt and extracellular signal related kinase 1/2(Erk1/2)signaling pathways were identified,and a proteomics analysis was conducted using SDSPAGE/liquid chromatography-tandem mass spectrometry analysis.Molecular interaction networks were visualized using the cytoscape bioinformatics platform.Protein expression of dedicator of cytokinesis1(DOCK1)and cytoskeleton intermediate filament vimentin were identified using an enzyme-linked immunosorbent assay,Western blotting,and small interfering RNA transfection of A549 cells.In xenograft A549-luc-C8 tumors in nude mice,enoxaparin+gefitinib inhibited tumor growth and reduced lung colony formation compared with gefitinib alone.Furthermore,the combination had stronger inhibitory effects on cell migration than either agent used individually.Additional enoxaparin administration resulted in better effective inhibition of Akt activity compared with gefitinib alone.Proteomics and network analysis implicated DOCK1 as the key node molecule.Western blot verified the effective inhibition of the expression of DOCK1 and vimentin phosphorylation by enoxaparin+gefitinib comparedwith gefitinib alone.DOCK1 knockdown confirmed its role in cell migration,Akt expression,and vimentin phosphorylation.Our data indicate that enoxaparin sensitizes gefitinib antitumor and antimigration activity in lung cancer by suppressing DOCK1 expression,Akt activity,and vimentin phosphorylation.
文摘Isoflavones which mainly distributed in leguminous plants have plenty of health benefits.Isoflavone synthase(IFS)is a membrane-associated cytochrome P450 enzyme(CYP450)which carries out the unique aryl-ring migration and hydroxylation.So far,few crystal structures of plant P450s have been obtained.We determined the crystal structure of IFS from Medicago truncatula at 1.9 by MAD method using a selenomethionine substituted crystal and conducted molecular docking and mutagenesis study.The structure of IFS complexed with imidazole exhibits the helix Iα-loop-helix Iβmotif which corresponds to helix I of other P 450s.Compared with structures of common P450s,IFS/imidazole structure contains an extra domain,i.e.,theγ-domain.The structure reveals a homodimer in which theγ-domain of one molecule interacts with theβ-domain of another.The plane of heme group makes an angle of approximately 40°with the helix Iα-loop-helix Iβmotif.Molecular docking combined with mutagenesis study suggested that Trp-128 and Asp-300 might play important roles in substrate binding and recognition.Phe-301,Ser-303 and Gly-305 from the helix Iα-loop-helix Iβmotif may play important roles in the aryl-ring migration.These novel structural features reveal insights into the unique reaction mechanism of IFS and provide a basis for engineering IFS in leguminous crops for health purpose.
基金The project supported by National Natural Science Foundation of China(81330074,81261160507,81170632,81370783,41376166)the 111Project,and International Science&Technology Cooperation Program of China 2012DFA11070
文摘OBJECTIVE Ganoderma lucidum polysaccharide peptides(GLPP)have an anti-oxidant activity.The oxidative stress implicates in the pathogenesis of renal ischemia-reperfusion injury(RIRI).The objective of this study was to determine whether GLPP could attenuate RIRI via counteracting the oxidative stress.METHODS Mice subjected to uninephrectomy with the right kidney ischemia for 35 min and reperfusion for 24 hwere used to explore the protective activity of GLPP against RIRI.In GLPP-treated group,100mg·kg-1·d-1 of GLPP were intraperitoneally injected for 7dbefore the procedure.In vitro,NRK-52 Ecells subjected to hypoxia-reoxygenation(H/R)and tunicamycin were used to explore the protective effect of GLPP against oxidative stress.The mechanisms in which GLPP protected kidney from RIRI were studied using a series of physiological and molecular biological methods.RESULTS Kidneys undergone ischemia-reperfusion showed renal dysfunction and characteristic morphological changes including cellular necrosis,brush border loss,cast formation,vacuolization and tubular dilatation while these damages were significantly attenuated by GLPP treatment.The abnormal levels of MPO,MDA and SOD caused by renal ischemia-reperfusion were significantly reversed by GLPP treatment.More apoptotic cells were found in the renal ischemia-reperfusion group than the sham group whereas GLPP reduced apoptotic cells in the ischemia-reperfusion mice by21.75%(P<0.01).The GLPPs(25-1μg·mL)alleviated H/R induced cell viability loss by 20.12%(P<0.01)andΔφm dissipation by 27.3%(P<0.01)in vitro as well and its pretreatment dramatically reduced H/R and tunicamycin induced cell injury.CONCLUSION Our study found that GLPP had a protective effect on RIRI via its anti-oxidative capacity,which suggests that GLPP may be developed as a candidate drug for preventing acute kidney injury.
基金National Natural Science Foundation of China(8133007481620108029+1 种基金81261160507)Beijing Natural Science Foundation(7172113)
文摘OBJECTIVE Ganoderma lucidum polysaccharide peptide(GLPP)is a group of extract from Ganoderma lucidum with a molecular mass of approximately 5×10^5,which ratio of polysaccharide to peptide is approximately 95%/5%.The purpose of this study was to determine whether GLPP has therapeutic effect on Non-alcoholic fatty liver disease(NAFLD).METHODS Ob/ob mouse model and ApoC3 transgenic mouse model were used for exploring the effect of GLPP on NAFLD.Key metabolic pathways and enzymes were identified by metabolomics combining with KEGG and PIUmet analyses and key enzymes were detected by Western blotting.Hepatosteatosis models of HepG2 cells and primary hepatocytes were used to further confirm the therapeutic effect of GLPP on NAFLD.RESULTS GLPP administrated for a month alleviated hepatosteatosis,dyslipidemia,liver dysfunction and liver insulin resistance.Pathways of glycerophos⁃pholipid metabolism,fatty acid metabolism and primary bile acid biosynthesis were involved in the therapeutic effect of GLPP on NAFLD.Detection of key enzymes revealed that GLPP reversed low expression of CYP7A1,CYP8B1,FXR,SHP and high expression of FGFR4 in ob/ob mice and ApoC3 mice.Besides,GLPP inhibited fatty acid synthesis by reducing the expression of SREBP1c,FAS and ACC via a FXR-SHP dependent mechanism.Additionally,GLPP reduced the accumulation of lipid droplets and the content of TG in HepG2 cells and primary hepatocytes induced by oleic acid and palmitic acid.CONCLUSION GLPP significantly improves NAFLD via regulating bile acid synthesis dependent on FXR-SHP/FGF pathway,which finally inhibits fatty acid synthesis,indicating that GLPP might be developed as a ther⁃apeutic drug for NAFLD.
基金supported by National Natural Science Foundation of China(81773932)
文摘OBJECTIVE Our group mainly focuses on the target identification and pharmacological mechanism study of TCM.We deeply identified the direct targets of the active ingredients in TCM using molecule probe-'Target Fishing' technology in chemical biology,and explored the related signaling pathways to explain the traditional efficiency of TCM.METHODS We synthesized biotin-tagged mole.cule probe by connecting biotin tag to TCM active molecule using PGE as a linker.Then,the biotintagged molecule probe was bound to the surface of solid beads by strong biotin-avidin interaction.Thus,the molecule probe-bound beads were mixed with cell lysates to capture the potential targets and identified by MS.RESULTS Our study found that SA which was an anti-inflammatory compound.could selectively bind to IMPDH2 in microglial cells,and SA showed weaker anti-inflammatory effect on IMPDH2-knock down microglial cells,suggesting IMPDH2 as a key anti-inflammatory target for SA.Ad.ditionally,handelin was a key anti-inflammatory compound.We identified the target protein of handelin as Hsp70 from microglial cells using target pull-down technology.Moreover,handelin showed weaker anti-inflammatory effect on Hsp70-knock down microglial cells,revealing that Hsp70 was the direct antiinflammatory target of handelin.CONCLUSION Our study provided methodology references for TCM target identification in the future,and also showed a new insight for exploring the pharmacological mechanism of TCM active ingredients.More importantly,we can perform scientific annotation for TCM efficiency by clarifying the biological functions of each target protein,showing important significance on modernization and internationalization of TCM.
基金supported by National Natural Science Foundation of China(81261160507,81330074,81620108029 and 81170632)Beijing Natural Science Foundation(7172113)
文摘OBJECTIVE Autosomal dominant polycystic kidney disease(ADPKD)is a common inherited disease with a high morbidity around 1/1000-1/400,characterized by progressive enlargement of fluid-fil ed cysts derived from renal tubular epithelial cells.Massive cysts gradually compress renal parenchyma destroying normal renal structures and compromising renal functions.Unfortunately,it will cause end-stage renal disease in most of the patients but without effective therapy now,who have to live on hemodialysis or kidney transplantation.Based on this present situation,it is of great significance to find early intervention to inhibit renal cyst development.The projective of this study was to investigate whether Ganoderma triterpenes(GT)can inhibit renal cyst development and study the related mechanism.METHODS and RESULTS First,we used MDCK cyst model,cultivated MDCK cells in vitro to form fluid-filled cysts surrounded by monolayer cells.GT inhibited MDCK cyst formation significantly,and inhibited cyst enlargement dose-dependently proving GT cyst inhibition in vitro.Then we used an embryonic kidney cyst model,wile-type mice kidneys were taken out on embryonic day 13.5 to form renal cysts stimulated with 8-Br-c AMP.GT inhibited embryonic kidney cyst development significantly in a dosedependent and reversible manner proving GT cyst inhibition at organ level.Furthermore,we used two ADPKD mouse models with severe cystic kidney disease phenotypes.GT dramatically inhibited renal cyst development,decreased ADPKD mouse kidney volume and the cyst index inside proving GT cyst inhibition in vivo.By Western blot,we proved GT down-regulated Ras/MAPK signal pathway without detectable effect on m TOR signal pathway both in MDCK cells and two ADPKD mouse kidneys.CONCLUSION GT retard renal cyst development both in vitro and in vivo significantly.The related mechanisms were involved in GT promoting renal tubular epithelial cell differentiation,down-regulating intracellular c AMP level and Ras/MAPK signal pathway.
