OBJECTIVE To investigate icariside(ICS)Ⅱ protects against PC12 cel damage induced by oxygen-glucose deprivation and reoxygenation and explore its mechanism.METHODS The oxidative stress injury model was induced by oxy...OBJECTIVE To investigate icariside(ICS)Ⅱ protects against PC12 cel damage induced by oxygen-glucose deprivation and reoxygenation and explore its mechanism.METHODS The oxidative stress injury model was induced by oxygen-glucose deprivation/reoxygenation(OGD/R) 2 h/24 h in PC12 cells.N-acetyl-lcysteine(NAC),a classical anti-oxidant,was used as positive control.Pharmacodynamic experimental study groups as follows:control,control+ICS Ⅱ50 μmol·L^(-1),OGD/R,OGD/R+ICSⅡ 12.5 μmol·L^(-1),OGD/R + ICS Ⅱ 25 μmol·L^(-1),OGD/R + ICS Ⅱ50 μmol·L^(-1),and OGD/R+NAC 100 μmol·L^(-1) groups.Cell viability and lactate dehydrogenase(LDH) leakage rate were measured by MTT assay and LDH ELISA kit,respectively.Moreover,reactive oxygen species(ROS) ELISA kit was used for detection of intracellular ROS generation,Mito-SOX fluorescence staining was used for detecting production of ROS in mitochondria and mitochondrial membrane potential(MMP)was detected by rhodamine 123 dye.In addition,PC12 cells apoptosis was detected by one-step TUNEL assay.Furthermore,the expressions of nuclear factor erythroid 2-related factors(Nrf2),Keap1,HO^(-1),NQO^(-1),silent information regulator 3(SIRT3),IDH2,Bax,Bcl-2 and caspase 3 were detected by Western blotting analysis.RESULTS The results of MTT and LDH assay showed that OGD/R reduced the cell viability and improved LDH release compared with the control or ICSⅡ 50 μmol·L^(-1) alone(P<0.01).Meanwhile,OGD/R not only increased intracellular and mitochondrial ROS generation,but also elevated the fluorescence intensity of TUNEL staining,at the same time,the MMP was declined when challenged by OGD/R.Furthermore,the Western blotting results showed that OGD/R induced the increase in the expression of cytoplasm-Nrf2,Keap1,Bax and cleaved-caspase 3 level,while the decrease in the expression of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).However,ICS Ⅱ significantly increased the viability of PC12 cells and reduced LDH leakage(P<0.01).Notably,ICS Ⅱ also suppressed ROS generation both in the intracellular and mitochondria,as well as restored MMP.It was also worthy to note that ICS Ⅱ decreased the expressions of cytoplasmNrf2,Keap1,Bax and the level of cleaved-caspase3,whereas,it increased the expressions of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).CONCLUSION ICSⅡ reduced OGD/Rinduced oxidative damage in PC12 cells under the laboratory conditions,and its underlying mechanism may be related to the regulation of Nrf2/SIRT3 signaling pathway.展开更多
Epimedium Brevicornum is a traditional Chinese medicinal plant possessing properties of sweet, warm, tonifying kidney, strong bones and rheumatism. Icariin, a flavonoid compound, is one of the main active ingredients ...Epimedium Brevicornum is a traditional Chinese medicinal plant possessing properties of sweet, warm, tonifying kidney, strong bones and rheumatism. Icariin, a flavonoid compound, is one of the main active ingredients of Epimedium. Icariinriside(ICS) is the main metabolite of icariin. Icariinand ICS have multiple pharmacological effects such as anti-tumor, anti-oxidative stress, improvement of cardiovascular and cerebrovascular, and regulation of endocrine. We have conducted a series of studies on the neuroprotection and mechanisms of action of icariin and ICS for many years. The main findings are reported as follows.(1) Effect on Alzheimer disease(AD) model animals: Icariin significantly attenuated learning and memory loss, hippocampal neuron loss and senile plaque formation in APP/PS1 transgenic AD model mice, which may be related to inhibition of Aβ production and reduction of PDE5(phosphodiesterase 5).In addition, icariin significantly attenuated Aβ25-35-induced learning and memory decline and hippocampal neuronal apoptosis in rats, which may be related to lowering PDE5 content and up-regulating BDNF/Trkb/CREB signaling pathway, inhibiting MAPK and NF-κB signaling pathways, and increasing expression of acetylcholinesterase(ACHE) and choline acetyltransferase(CHAT) in the hippocampus. At the same time, icariin can significantly improve the learning and memory dysfunction induced by amanita proline in rats, which may be related to the inhibition of hippocampal neuronal apoptosis, antiexcitatory amino acid toxicity and regulation of MAPK and NF-κB signaling pathways.(2) Effects on Parkinson disease(PD) model animals: The study found that in LPS-induced dopaminergic neuron injury animal models and cell models, icariin can inhibit microglia by inhibiting the expression of inflammatory factors such as TNF-α, IL-1β, NO and COX-2. Activation of glial cells increases the expression of neurotrophic factors such as BDNF and GDNF, increases the content of dopamine(DA) and its metabolites 3, 4-dihydroxyphenylacetic acid(DOPAC) and homovanillic acid(HVA), inhibits MAPK and the NF-κB signaling pathway, protecting dopaminergic neurons. In addition, icariin significantly attenuated6-OHDA-induced dopaminergic neuronal damage. In Nrf2 knockout mice, the neuroprotective effect of icariin disappeared, suggesting that Nrf2 may be one of the targets of icariin to play neuroprotective effects.(3) Effects on vascular dementia(VD) model animals: Icarin can improve the learning and memory ability and memory function of chronic hypoperfusion rats, and its mechanism may be related to increase the level of VEGF/VEGFR2 protein in the brain and activate multiple downstream signaling pathways to promote angiogenesis to play an indirect protective effect on neurons;The level of BDNF/Trk B protein in the brain increases the phosphorylation level of CREB and exerts direct neuroprotective effects.(4)Effect on cerebral ischemia: In a model of ischemic brain injury, icariin acts to up-regulate Sirt1 by activating p38, thereby exerting an anti-ischemic injury and protecting neuronal cells. In addition, icariin has neuroprotective effects on cerebral ischemia-reperfusion injury in rats, which may increase GSH-Px,SOD activity, decrease MDA content, inhibit free radical damage, reduce NO content, NOS activity,and inhibit neurotoxic damage. Reduction of MPO activity, TNF-α, IL-1β content is associated with inhibition of inflammatory response.(5) Cell protection: Icariin has a protective effect on 6-OHDA-induced oxidative damage in PC12 cells, which may be related to inhibition of apoptosis and regulation of Keap1/Nrf2/ARE signaling pathway, while ICS can attenuate oxygen-glucose deprivation/reoxygenation-induced cellular damage in PC12 cells. The mechanism of cellular oxidative damage may be related to inhibition of apoptosis and regulation of Nrf2/SIRT3 signaling pathway.Icariin and ICS have good preventive and therapeutic effects on central nervous system diseases such as AD, PD, VD, etc. However, due to the complexity of the molecular mechanisms of icariin and ICS, the molecular mechanisms of the central nervous system are still worthy of further study.展开更多
OBJECTIVE Alzheimer disease(AD) is a progressive neurodegenerative disorder involving a gradual decline in many cognitive processes and in neurons.The endoplasmic reticulum(ER) is involved in several crucial cellular ...OBJECTIVE Alzheimer disease(AD) is a progressive neurodegenerative disorder involving a gradual decline in many cognitive processes and in neurons.The endoplasmic reticulum(ER) is involved in several crucial cellular functions,eg protein folding and quality control.Massive misfolded or unfolded proteins in ER can disturb the function of ER and induce ER stress,which results in neuronal death in AD.Icariin(ICA) has a wide range of neuro protection and has been researched in AD treatment.However,whether ICA has the effect on ER stress in AD condition,and how ICA affects ER stress remains stil unclear.Therefore,the current study aimed to investigate the mechanism of ICA against cognitive impairments in AD model through ER stress pathway and apoptosis.METHODS Twelve months male APP/PS1 or wild-type(WT)mice were randomly divided into four groups:APP/PS1,and APP/PS1+ICA,WT and WT+ICA groups.The treated mice were given ICA60 mg·kg-1 per day and control mice were received the same volume distilled water for consecutive 3 months.The Morris water maze and novel object recognition were used to detect animals′ behavior.Nissl staining was used to observe the neuronal morphology in hippocampus area.The protein and(or) phosphorylation level of GRP78,p-PERK,PERK,p-IRE1,IRE1,ATF6,p-e IF2α,eIF2α,ATF4,CHOP,the level of cleaved-casepase 3,Bax and Bcl-2 were examined by Western blotting.RESULTS The behavior performance testing by Morris water maze and novel object recognition deteriorated in APP/PS1 mice compared with WT mice,however,ICA significantly improved the behavior performance when compared with APP/PS1.The neuron impairments in APP/PS1 mice also were ameliorated after ICA treatment.The protein expression of GRP78,ATF4,CHOP,and the level of p-PERK and p-eI F2α were higher in APP/PS1 mice than that in WT mice.The Bax/Bcl-2 ratio elevation and caspase 3 activation have been found in APP/PS1 mice.After treated with ICA,those above-mentioned parameters were decreased compared with APP/PS1.However,the levels of IRE1,p-IRE1 and ATF6 were not change among other groups.CONCLUSION ICA may decrease the ER stress and apoptosis in AD model,and may be through inhibiting the PERK/eI F2α pathway,not IRE and ATF6 pathways.展开更多
OBJECTIVE To investigate the effect of icariin Ⅱ(ICS Ⅱ) on lipopolysaccharide(LPS)-induced inflammation and amyloid production in astrocytes.METHODS The cerebral cortex of newborn SD rats was isolated in vitro,and t...OBJECTIVE To investigate the effect of icariin Ⅱ(ICS Ⅱ) on lipopolysaccharide(LPS)-induced inflammation and amyloid production in astrocytes.METHODS The cerebral cortex of newborn SD rats was isolated in vitro,and the primary astrocytes were extracted and cultured.Astrocytes were pre-treated with ICSⅡ(5,10 and20 μmol·L^(-1)) or dexamethasone(1 μmol·L^(-1)) for1 h.Cell inflammation models were established with LPS and treated with ICS Ⅱ or dexamethasone for another 24 h.The anti-neuroinflammation and anti-amyloid effects of ICS Ⅱ in astrocytes were detected by ELISA and Western blotting respectively.RESULTS ICS Ⅱ decreased the levels of beta secretase 1(BACE1),Aβ1-40 and Aβ1-42 in astrocytes in a concentration-dependent manner.Moreover,the levels of tumor necrosis factor-alpha,interleukin-1β,reactive oxygen species,inducible nitric oxide synthase,cyclooxygenase-2 and transforming growth factor-β1 in astrocytes were significantly inhibited by ICS II(5,10 and 20 μmol·L^(-1)).In addition,ICSⅡhas a significant inhibitory effect on LPS-induced IκB-α degradation and NF-κB activation.CONCLUSION ICS Ⅱ exerts neuroprotective effects on LPS-induced inflammation in astrocytes,through regulating IKK/IκB/NF-κB signaling pathway.展开更多
OBJECTIVE To explore the effect of icariside Ⅱ(ICS Ⅱ) on oxygen-glucose deprivation and reoxygenation(OGD/R)-induced injury in cerebral cortical neuronal cels.METHODS Primary cerebral cortical neuronal cells were de...OBJECTIVE To explore the effect of icariside Ⅱ(ICS Ⅱ) on oxygen-glucose deprivation and reoxygenation(OGD/R)-induced injury in cerebral cortical neuronal cels.METHODS Primary cerebral cortical neuronal cells were deprived of oxygen and glucose for 2 h to simulate ischemic stroke injury in vitro.The experiment was divided into 8 groups,which were control,control+ICSⅡ 25 μmol·L^(-1),OGD/R,OGD/R+ICSⅡ(6.25,12.5,25 μmol·L^(-1)),OGD/R+3-methyladenine(3-MA) and OGD/R+Rapamycin(Rap).The protective effect of ICS Ⅱ were detected by MTT assay and lactate dehydrogenase(LDH),respectively.Autophagic flux and autophagy related proteins expressions were detected by using adenovirus harboring tf-LC3 and Western blotting,respectively.RESULTS Compared with OGD/R group,the cell viability treated with ICSⅡwas elevated in a concentration-dependent manner,and the leakage rate of LDH was lowed.Moreover,ICSⅡ not only suppressed OGD/R-induced autophagic flux,but also inhibited the increase of LC3-Ⅱ/LC3-Ⅰ ratio and Beclin 1 after OGD/R insulted.CONCLUSION ICS Ⅱ exerts protective effects on OGD/R-induced cerebral cortical neuronal cells through inhibiting excessive autophagy.展开更多
OBJECTIVE To explore the effects and mechanism of icariside Ⅱ(ICS Ⅱ),a pharmacologically active compound derived from herbal Epimedii with previous study-proved phosphodiesterase 5(PDE5) inhibitors,was investigated ...OBJECTIVE To explore the effects and mechanism of icariside Ⅱ(ICS Ⅱ),a pharmacologically active compound derived from herbal Epimedii with previous study-proved phosphodiesterase 5(PDE5) inhibitors,was investigated in vivo using a middle cerebral artery occlusion/reperfusion(MCAO/R) model in rats and in vitro using an oxygen-glucose deprivation/reperfusion(OGD/R) model in primary hippocampal neurons.METHODS Laser Doppler flowmeter was introduced to examine the cerebral blood flow of MCAO/R rats.The neurological deficits scores,brain water content and infarction volume were assessed after MCAO/R.OGD/R-induced primary hippocampal neuronal injury and apoptosis were examined by MTT,lactate dehydrogenase(LDH) release,TUNEL staining and flow cytometry,respectively.Expressions of PDE5 A and memory-related signaling pathways were measured using Western blotting analysis.The direct interaction between ICS Ⅱand PDE5 was further evaluated by molecular docking.RESULTS ICS Ⅱ significantly decreased the infraction volume in MCAO/R rats.Furthermore,ICS Ⅱ significantly abrogated OGD/R-induced hippocampal neuronal death.Moreover,ICSⅡ not only effectively restored the 3′ 5′-cyclic guanosine monophosphate(cGMP) level and protein kinase G(PKG) activity both in vivo and in vitro,but also increased brain-derived neurotrophic factor(BDNF),tyrosine protein kinase B(TrkB) and cAMP response element-binding protein(CREB) expressions,thereby inhibited hippocampal neuronal apoptosis.Mechanistically,the beneficial effects of ICS Ⅱ was attributed to its activation of the PKG/TrkB/BDNF via increasing BDNF expression,evidenced by that the inhibition effects of ICSⅡ was abrogated by Rp-8-BrcGMPS,a PKG inhibitor,or ANA-12,a TrkB inhibitor.ICSⅡ also decreased both protein level and activity of PDE5.Notably,ICSⅡ might effectively bind and inhibite PDE5 as demonstrated by relatively high binding score.CONCLUSION ICSⅡ significantly protect against cerebral ischemia/reperfusion injury in rats and rescues OGD/Rinduced hippocampal neuronal injury,and the underling mechanisms are,at least partly,due to inhibition of PDE5 and activation of BDNF/TrkB/CREB signaling pathway.Hence ICS Ⅱ may be an effective agent for combating cerebral ischemia/reperfusion injury.展开更多
OBJECTIVE To investigate the inhibitory effect and mechanism of sodium ferulate(SF)on myocardial hypertrophy in spontaneously hypertensive(SHR).METHODS Forty 14-week-old SHR male rats were randomly divided into model ...OBJECTIVE To investigate the inhibitory effect and mechanism of sodium ferulate(SF)on myocardial hypertrophy in spontaneously hypertensive(SHR).METHODS Forty 14-week-old SHR male rats were randomly divided into model group(SHR,receive distilled water)and SF treatment groups(SF 20,40 and 80 mg·kg^-1 per day,respectively).Age-matched male Wistar-Kyoto(WKY)rats gavaged with distilled water served as controls.After 12 weeks of treatment,the effects of SF on cardiac hypertrophy were evaluated using echocardiographic measurement,pathological analysis and the expression of atrial natriuretic peptide(ANP),myosin heavy chainβ(β-MHC)-a gene related to myocardial hypertrophy.In order to explore the mechanism of SF on myocardial hypertrophy,the calcium-sensing receptor(CaSR),calcineurin(CaN),nuclear factor of activated T cell 3(NFAT3),phosphorylation NFAT3(p-NFAT3),zinc finger transcription factor(GATA4),phosphorylation GATA4(p-GATA4),protein kinase Cβ(PKC-β),Raf-1,extracellular regulated protein kinase 1/2(ERK 1/2),phosphorylation ERK1/2(p-ERK 1/2)and mitogen-activated protein kinase phosphatase-1(MKP-1)were detected.RESULTS The myocardial hypertrophy parameters,myocardial cell cross section area,left ventricular wall thickness and expression of ANP and β-MHC,CaSR,CaN,NFAT3,p-GATA4,PKC-β,Raf-1,and p-ERK 1/2 were significantly increased,while the left ventricular cavity was significantly smaller,expression of p-NFAT3 and MKP-1 were significantly decreased,meanwhile,the ultra⁃structure of cardiomyocytes was significantly damaged in 26-week-old SHR rats.Notably,SF significantly ameliorated myocardial hyper⁃trophy in 26-week-old SHR rats;suppressed the overexpression of ANP,β-MHC,CaSR,CaN,NFAT3,p-GATA4,PKC-β,Raf-1,and p-ERK 1/2 and increased the expression of p-NFAT3 and MKP-1.CONCLUSION SF can inhibit cardiac hypertrophy in SHR rats,and the mechanism may be related to the inhibition of CaSR mediated signaling pathway.展开更多
Objective: To investigate the effects of evodiamine(Evo), a component of Evodiaminedia rutaecarpa(Juss.) Benth, on cardiomyocyte hypertrophy induced by angiotensin Ⅱ(Ang Ⅱ) and further explore the potential mechanis...Objective: To investigate the effects of evodiamine(Evo), a component of Evodiaminedia rutaecarpa(Juss.) Benth, on cardiomyocyte hypertrophy induced by angiotensin Ⅱ(Ang Ⅱ) and further explore the potential mechanisms. Methods: Cardiomyocytes from neonatal Sprague Dawley rats were isolated and characterized, and then the cadiomyocyte cultures were randomly divided into control, model(Ang Ⅱ 0.1 μmol/L), and Evo(0.03, 0.3, 3 μmol/L) groups. The cardiomyocyte surface area, protein level, intracellular free calcium([Ca]i) concentration, activity of nitric oxide synthase(NOS) and content of nitric oxide(NO) were measured, respectively. The m RNA expressions of atrial natriuretic factor(ANF), calcineurin(CaN), extracellular signal-regulated kinase-2(ERK-2), and endothelial nitric oxide synthase(e NOS) of cardiomyocytes were analyzed by real-time reverse transcriptionpolymerase chain reaction. The protein expressions of calcineurin catalytic subunit(CnA) and mitogen-activated protein kinase phosphatase-1(MKP-1) were detected by Western blot analysis. Results: Compared with the control group, Ang Ⅱ induced cardiomyocytes hypertrophy, as evidenced by increased cardiomyocyte surface area, protein content, and ANF m RNA expression; increased intracellular free calcium([Ca]i) concentration and expressions of CaN m RNA, CnA protein, and ERK-2 m RNA, but decreased MKP-1 protein expression(P<0.05 or P<0.01). Compared with Ang Ⅱ, Evo(0.3, 3 μmol/L) significantly attenuated Ang Ⅱ-induced cardiomyocyte hypertrophy, decreased the [Ca]i concentration and expressions of CaN m RNA, CnA protein, and ERK-2 m RNA, but increased MKP-1 protein expression(P<0.05 or P<0.01). Most interestingly, Evo increased the NOS activity and NO production, and upregulated the e NOS m RNA expression(P<0.05). Conclusion: Evo significantly attenuated Ang Ⅱ-induced cardiomyocyte hypertrophy, and this effect was partly due to promotion of NO production, reduction of [Ca]i concentration, and inhibition of CaN and ERK-2 signal transduction pathways.展开更多
基金National Natural Science Foundation of China(81560666)Program for Excellent Young Talents of Zunyi Medical Uiverstity(15zy-002)+1 种基金Science and Technology Innovation Talent Team of Guizhou Province(20154023)the ″Hundred″Level of High-level Innovative Talents in Guizhou Province(QKHRCPT 20165684);and Program forChangjiang Scholars and Innovative ResearchTeam in University of China(IRT一17R113).
文摘OBJECTIVE To investigate icariside(ICS)Ⅱ protects against PC12 cel damage induced by oxygen-glucose deprivation and reoxygenation and explore its mechanism.METHODS The oxidative stress injury model was induced by oxygen-glucose deprivation/reoxygenation(OGD/R) 2 h/24 h in PC12 cells.N-acetyl-lcysteine(NAC),a classical anti-oxidant,was used as positive control.Pharmacodynamic experimental study groups as follows:control,control+ICS Ⅱ50 μmol·L^(-1),OGD/R,OGD/R+ICSⅡ 12.5 μmol·L^(-1),OGD/R + ICS Ⅱ 25 μmol·L^(-1),OGD/R + ICS Ⅱ50 μmol·L^(-1),and OGD/R+NAC 100 μmol·L^(-1) groups.Cell viability and lactate dehydrogenase(LDH) leakage rate were measured by MTT assay and LDH ELISA kit,respectively.Moreover,reactive oxygen species(ROS) ELISA kit was used for detection of intracellular ROS generation,Mito-SOX fluorescence staining was used for detecting production of ROS in mitochondria and mitochondrial membrane potential(MMP)was detected by rhodamine 123 dye.In addition,PC12 cells apoptosis was detected by one-step TUNEL assay.Furthermore,the expressions of nuclear factor erythroid 2-related factors(Nrf2),Keap1,HO^(-1),NQO^(-1),silent information regulator 3(SIRT3),IDH2,Bax,Bcl-2 and caspase 3 were detected by Western blotting analysis.RESULTS The results of MTT and LDH assay showed that OGD/R reduced the cell viability and improved LDH release compared with the control or ICSⅡ 50 μmol·L^(-1) alone(P<0.01).Meanwhile,OGD/R not only increased intracellular and mitochondrial ROS generation,but also elevated the fluorescence intensity of TUNEL staining,at the same time,the MMP was declined when challenged by OGD/R.Furthermore,the Western blotting results showed that OGD/R induced the increase in the expression of cytoplasm-Nrf2,Keap1,Bax and cleaved-caspase 3 level,while the decrease in the expression of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).However,ICS Ⅱ significantly increased the viability of PC12 cells and reduced LDH leakage(P<0.01).Notably,ICS Ⅱ also suppressed ROS generation both in the intracellular and mitochondria,as well as restored MMP.It was also worthy to note that ICS Ⅱ decreased the expressions of cytoplasmNrf2,Keap1,Bax and the level of cleaved-caspase3,whereas,it increased the expressions of nucleus-Nrf2,HO^(-1),NQO^(-1),SIRT3,IDH2 and Bcl-2(P<0.05).CONCLUSION ICSⅡ reduced OGD/Rinduced oxidative damage in PC12 cells under the laboratory conditions,and its underlying mechanism may be related to the regulation of Nrf2/SIRT3 signaling pathway.
文摘Epimedium Brevicornum is a traditional Chinese medicinal plant possessing properties of sweet, warm, tonifying kidney, strong bones and rheumatism. Icariin, a flavonoid compound, is one of the main active ingredients of Epimedium. Icariinriside(ICS) is the main metabolite of icariin. Icariinand ICS have multiple pharmacological effects such as anti-tumor, anti-oxidative stress, improvement of cardiovascular and cerebrovascular, and regulation of endocrine. We have conducted a series of studies on the neuroprotection and mechanisms of action of icariin and ICS for many years. The main findings are reported as follows.(1) Effect on Alzheimer disease(AD) model animals: Icariin significantly attenuated learning and memory loss, hippocampal neuron loss and senile plaque formation in APP/PS1 transgenic AD model mice, which may be related to inhibition of Aβ production and reduction of PDE5(phosphodiesterase 5).In addition, icariin significantly attenuated Aβ25-35-induced learning and memory decline and hippocampal neuronal apoptosis in rats, which may be related to lowering PDE5 content and up-regulating BDNF/Trkb/CREB signaling pathway, inhibiting MAPK and NF-κB signaling pathways, and increasing expression of acetylcholinesterase(ACHE) and choline acetyltransferase(CHAT) in the hippocampus. At the same time, icariin can significantly improve the learning and memory dysfunction induced by amanita proline in rats, which may be related to the inhibition of hippocampal neuronal apoptosis, antiexcitatory amino acid toxicity and regulation of MAPK and NF-κB signaling pathways.(2) Effects on Parkinson disease(PD) model animals: The study found that in LPS-induced dopaminergic neuron injury animal models and cell models, icariin can inhibit microglia by inhibiting the expression of inflammatory factors such as TNF-α, IL-1β, NO and COX-2. Activation of glial cells increases the expression of neurotrophic factors such as BDNF and GDNF, increases the content of dopamine(DA) and its metabolites 3, 4-dihydroxyphenylacetic acid(DOPAC) and homovanillic acid(HVA), inhibits MAPK and the NF-κB signaling pathway, protecting dopaminergic neurons. In addition, icariin significantly attenuated6-OHDA-induced dopaminergic neuronal damage. In Nrf2 knockout mice, the neuroprotective effect of icariin disappeared, suggesting that Nrf2 may be one of the targets of icariin to play neuroprotective effects.(3) Effects on vascular dementia(VD) model animals: Icarin can improve the learning and memory ability and memory function of chronic hypoperfusion rats, and its mechanism may be related to increase the level of VEGF/VEGFR2 protein in the brain and activate multiple downstream signaling pathways to promote angiogenesis to play an indirect protective effect on neurons;The level of BDNF/Trk B protein in the brain increases the phosphorylation level of CREB and exerts direct neuroprotective effects.(4)Effect on cerebral ischemia: In a model of ischemic brain injury, icariin acts to up-regulate Sirt1 by activating p38, thereby exerting an anti-ischemic injury and protecting neuronal cells. In addition, icariin has neuroprotective effects on cerebral ischemia-reperfusion injury in rats, which may increase GSH-Px,SOD activity, decrease MDA content, inhibit free radical damage, reduce NO content, NOS activity,and inhibit neurotoxic damage. Reduction of MPO activity, TNF-α, IL-1β content is associated with inhibition of inflammatory response.(5) Cell protection: Icariin has a protective effect on 6-OHDA-induced oxidative damage in PC12 cells, which may be related to inhibition of apoptosis and regulation of Keap1/Nrf2/ARE signaling pathway, while ICS can attenuate oxygen-glucose deprivation/reoxygenation-induced cellular damage in PC12 cells. The mechanism of cellular oxidative damage may be related to inhibition of apoptosis and regulation of Nrf2/SIRT3 signaling pathway.Icariin and ICS have good preventive and therapeutic effects on central nervous system diseases such as AD, PD, VD, etc. However, due to the complexity of the molecular mechanisms of icariin and ICS, the molecular mechanisms of the central nervous system are still worthy of further study.
基金National Natural Science Foundation of China(81560594).
文摘OBJECTIVE Alzheimer disease(AD) is a progressive neurodegenerative disorder involving a gradual decline in many cognitive processes and in neurons.The endoplasmic reticulum(ER) is involved in several crucial cellular functions,eg protein folding and quality control.Massive misfolded or unfolded proteins in ER can disturb the function of ER and induce ER stress,which results in neuronal death in AD.Icariin(ICA) has a wide range of neuro protection and has been researched in AD treatment.However,whether ICA has the effect on ER stress in AD condition,and how ICA affects ER stress remains stil unclear.Therefore,the current study aimed to investigate the mechanism of ICA against cognitive impairments in AD model through ER stress pathway and apoptosis.METHODS Twelve months male APP/PS1 or wild-type(WT)mice were randomly divided into four groups:APP/PS1,and APP/PS1+ICA,WT and WT+ICA groups.The treated mice were given ICA60 mg·kg-1 per day and control mice were received the same volume distilled water for consecutive 3 months.The Morris water maze and novel object recognition were used to detect animals′ behavior.Nissl staining was used to observe the neuronal morphology in hippocampus area.The protein and(or) phosphorylation level of GRP78,p-PERK,PERK,p-IRE1,IRE1,ATF6,p-e IF2α,eIF2α,ATF4,CHOP,the level of cleaved-casepase 3,Bax and Bcl-2 were examined by Western blotting.RESULTS The behavior performance testing by Morris water maze and novel object recognition deteriorated in APP/PS1 mice compared with WT mice,however,ICA significantly improved the behavior performance when compared with APP/PS1.The neuron impairments in APP/PS1 mice also were ameliorated after ICA treatment.The protein expression of GRP78,ATF4,CHOP,and the level of p-PERK and p-eI F2α were higher in APP/PS1 mice than that in WT mice.The Bax/Bcl-2 ratio elevation and caspase 3 activation have been found in APP/PS1 mice.After treated with ICA,those above-mentioned parameters were decreased compared with APP/PS1.However,the levels of IRE1,p-IRE1 and ATF6 were not change among other groups.CONCLUSION ICA may decrease the ER stress and apoptosis in AD model,and may be through inhibiting the PERK/eI F2α pathway,not IRE and ATF6 pathways.
基金National Natural Science Foundation of China (81560585).
文摘OBJECTIVE To investigate the effect of icariin Ⅱ(ICS Ⅱ) on lipopolysaccharide(LPS)-induced inflammation and amyloid production in astrocytes.METHODS The cerebral cortex of newborn SD rats was isolated in vitro,and the primary astrocytes were extracted and cultured.Astrocytes were pre-treated with ICSⅡ(5,10 and20 μmol·L^(-1)) or dexamethasone(1 μmol·L^(-1)) for1 h.Cell inflammation models were established with LPS and treated with ICS Ⅱ or dexamethasone for another 24 h.The anti-neuroinflammation and anti-amyloid effects of ICS Ⅱ in astrocytes were detected by ELISA and Western blotting respectively.RESULTS ICS Ⅱ decreased the levels of beta secretase 1(BACE1),Aβ1-40 and Aβ1-42 in astrocytes in a concentration-dependent manner.Moreover,the levels of tumor necrosis factor-alpha,interleukin-1β,reactive oxygen species,inducible nitric oxide synthase,cyclooxygenase-2 and transforming growth factor-β1 in astrocytes were significantly inhibited by ICS II(5,10 and 20 μmol·L^(-1)).In addition,ICSⅡhas a significant inhibitory effect on LPS-induced IκB-α degradation and NF-κB activation.CONCLUSION ICS Ⅱ exerts neuroprotective effects on LPS-induced inflammation in astrocytes,through regulating IKK/IκB/NF-κB signaling pathway.
基金National Natural Science Foundation of China(81560666)Program for Changjiang Scholarsand Innovative Research Team in University, China(IRT_17R113).
文摘OBJECTIVE To explore the effect of icariside Ⅱ(ICS Ⅱ) on oxygen-glucose deprivation and reoxygenation(OGD/R)-induced injury in cerebral cortical neuronal cels.METHODS Primary cerebral cortical neuronal cells were deprived of oxygen and glucose for 2 h to simulate ischemic stroke injury in vitro.The experiment was divided into 8 groups,which were control,control+ICSⅡ 25 μmol·L^(-1),OGD/R,OGD/R+ICSⅡ(6.25,12.5,25 μmol·L^(-1)),OGD/R+3-methyladenine(3-MA) and OGD/R+Rapamycin(Rap).The protective effect of ICS Ⅱ were detected by MTT assay and lactate dehydrogenase(LDH),respectively.Autophagic flux and autophagy related proteins expressions were detected by using adenovirus harboring tf-LC3 and Western blotting,respectively.RESULTS Compared with OGD/R group,the cell viability treated with ICSⅡwas elevated in a concentration-dependent manner,and the leakage rate of LDH was lowed.Moreover,ICSⅡ not only suppressed OGD/R-induced autophagic flux,but also inhibited the increase of LC3-Ⅱ/LC3-Ⅰ ratio and Beclin 1 after OGD/R insulted.CONCLUSION ICS Ⅱ exerts protective effects on OGD/R-induced cerebral cortical neuronal cells through inhibiting excessive autophagy.
基金National Natural Science Foundation of China(81560585)Program for Excellent Young Talentsof Zunyi Medical University(15zy-002)+2 种基金Scienceand Technology Innovation Talent Team of GuizhouProvince(20154023)the hundred”Level of High—level Innovative Talents in Guizhou Province(QKHRCPT 20165684):Education Department of Guizhou Province of China[GNYL(2017)006,YLXKJS—YS一06]Program for Changjiang Scholars and lnnovative Research Team in University,China(IRT-17R113).
文摘OBJECTIVE To explore the effects and mechanism of icariside Ⅱ(ICS Ⅱ),a pharmacologically active compound derived from herbal Epimedii with previous study-proved phosphodiesterase 5(PDE5) inhibitors,was investigated in vivo using a middle cerebral artery occlusion/reperfusion(MCAO/R) model in rats and in vitro using an oxygen-glucose deprivation/reperfusion(OGD/R) model in primary hippocampal neurons.METHODS Laser Doppler flowmeter was introduced to examine the cerebral blood flow of MCAO/R rats.The neurological deficits scores,brain water content and infarction volume were assessed after MCAO/R.OGD/R-induced primary hippocampal neuronal injury and apoptosis were examined by MTT,lactate dehydrogenase(LDH) release,TUNEL staining and flow cytometry,respectively.Expressions of PDE5 A and memory-related signaling pathways were measured using Western blotting analysis.The direct interaction between ICS Ⅱand PDE5 was further evaluated by molecular docking.RESULTS ICS Ⅱ significantly decreased the infraction volume in MCAO/R rats.Furthermore,ICS Ⅱ significantly abrogated OGD/R-induced hippocampal neuronal death.Moreover,ICSⅡ not only effectively restored the 3′ 5′-cyclic guanosine monophosphate(cGMP) level and protein kinase G(PKG) activity both in vivo and in vitro,but also increased brain-derived neurotrophic factor(BDNF),tyrosine protein kinase B(TrkB) and cAMP response element-binding protein(CREB) expressions,thereby inhibited hippocampal neuronal apoptosis.Mechanistically,the beneficial effects of ICS Ⅱ was attributed to its activation of the PKG/TrkB/BDNF via increasing BDNF expression,evidenced by that the inhibition effects of ICSⅡ was abrogated by Rp-8-BrcGMPS,a PKG inhibitor,or ANA-12,a TrkB inhibitor.ICSⅡ also decreased both protein level and activity of PDE5.Notably,ICSⅡ might effectively bind and inhibite PDE5 as demonstrated by relatively high binding score.CONCLUSION ICSⅡ significantly protect against cerebral ischemia/reperfusion injury in rats and rescues OGD/Rinduced hippocampal neuronal injury,and the underling mechanisms are,at least partly,due to inhibition of PDE5 and activation of BDNF/TrkB/CREB signaling pathway.Hence ICS Ⅱ may be an effective agent for combating cerebral ischemia/reperfusion injury.
基金National Natural Science Foundation of China(81860732)Scientific and Technological Projects for Social Development in Guizhou Province of China([2011]3036)the State Key Laboratory of Cardiovascular Disease(2017kf-03)
文摘OBJECTIVE To investigate the inhibitory effect and mechanism of sodium ferulate(SF)on myocardial hypertrophy in spontaneously hypertensive(SHR).METHODS Forty 14-week-old SHR male rats were randomly divided into model group(SHR,receive distilled water)and SF treatment groups(SF 20,40 and 80 mg·kg^-1 per day,respectively).Age-matched male Wistar-Kyoto(WKY)rats gavaged with distilled water served as controls.After 12 weeks of treatment,the effects of SF on cardiac hypertrophy were evaluated using echocardiographic measurement,pathological analysis and the expression of atrial natriuretic peptide(ANP),myosin heavy chainβ(β-MHC)-a gene related to myocardial hypertrophy.In order to explore the mechanism of SF on myocardial hypertrophy,the calcium-sensing receptor(CaSR),calcineurin(CaN),nuclear factor of activated T cell 3(NFAT3),phosphorylation NFAT3(p-NFAT3),zinc finger transcription factor(GATA4),phosphorylation GATA4(p-GATA4),protein kinase Cβ(PKC-β),Raf-1,extracellular regulated protein kinase 1/2(ERK 1/2),phosphorylation ERK1/2(p-ERK 1/2)and mitogen-activated protein kinase phosphatase-1(MKP-1)were detected.RESULTS The myocardial hypertrophy parameters,myocardial cell cross section area,left ventricular wall thickness and expression of ANP and β-MHC,CaSR,CaN,NFAT3,p-GATA4,PKC-β,Raf-1,and p-ERK 1/2 were significantly increased,while the left ventricular cavity was significantly smaller,expression of p-NFAT3 and MKP-1 were significantly decreased,meanwhile,the ultra⁃structure of cardiomyocytes was significantly damaged in 26-week-old SHR rats.Notably,SF significantly ameliorated myocardial hyper⁃trophy in 26-week-old SHR rats;suppressed the overexpression of ANP,β-MHC,CaSR,CaN,NFAT3,p-GATA4,PKC-β,Raf-1,and p-ERK 1/2 and increased the expression of p-NFAT3 and MKP-1.CONCLUSION SF can inhibit cardiac hypertrophy in SHR rats,and the mechanism may be related to the inhibition of CaSR mediated signaling pathway.
基金Supported by the National Natural Science Foundation of China(No.81160528)Foundation of Administration of Traditional Chinese Medicine of Guizhou Province(No.2009-79)
文摘Objective: To investigate the effects of evodiamine(Evo), a component of Evodiaminedia rutaecarpa(Juss.) Benth, on cardiomyocyte hypertrophy induced by angiotensin Ⅱ(Ang Ⅱ) and further explore the potential mechanisms. Methods: Cardiomyocytes from neonatal Sprague Dawley rats were isolated and characterized, and then the cadiomyocyte cultures were randomly divided into control, model(Ang Ⅱ 0.1 μmol/L), and Evo(0.03, 0.3, 3 μmol/L) groups. The cardiomyocyte surface area, protein level, intracellular free calcium([Ca]i) concentration, activity of nitric oxide synthase(NOS) and content of nitric oxide(NO) were measured, respectively. The m RNA expressions of atrial natriuretic factor(ANF), calcineurin(CaN), extracellular signal-regulated kinase-2(ERK-2), and endothelial nitric oxide synthase(e NOS) of cardiomyocytes were analyzed by real-time reverse transcriptionpolymerase chain reaction. The protein expressions of calcineurin catalytic subunit(CnA) and mitogen-activated protein kinase phosphatase-1(MKP-1) were detected by Western blot analysis. Results: Compared with the control group, Ang Ⅱ induced cardiomyocytes hypertrophy, as evidenced by increased cardiomyocyte surface area, protein content, and ANF m RNA expression; increased intracellular free calcium([Ca]i) concentration and expressions of CaN m RNA, CnA protein, and ERK-2 m RNA, but decreased MKP-1 protein expression(P<0.05 or P<0.01). Compared with Ang Ⅱ, Evo(0.3, 3 μmol/L) significantly attenuated Ang Ⅱ-induced cardiomyocyte hypertrophy, decreased the [Ca]i concentration and expressions of CaN m RNA, CnA protein, and ERK-2 m RNA, but increased MKP-1 protein expression(P<0.05 or P<0.01). Most interestingly, Evo increased the NOS activity and NO production, and upregulated the e NOS m RNA expression(P<0.05). Conclusion: Evo significantly attenuated Ang Ⅱ-induced cardiomyocyte hypertrophy, and this effect was partly due to promotion of NO production, reduction of [Ca]i concentration, and inhibition of CaN and ERK-2 signal transduction pathways.