OBJECTIVE To investigate the effects of Radix Cynanchum bungei extract(RCBE) on cerebral ischemia-reperfusion(I/R) and acute cerebral ischemia induced impairment in mice.METHODS I/R model was induced by bilateral caro...OBJECTIVE To investigate the effects of Radix Cynanchum bungei extract(RCBE) on cerebral ischemia-reperfusion(I/R) and acute cerebral ischemia induced impairment in mice.METHODS I/R model was induced by bilateral carotid artery occlusion(BCAO)-reperfusion method and Y-maze learning and memory performance was assessed after reperfusion. Na^+-K^+-ATPase,Ca^(2+)-ATPase and SOD activity,as well as MDA content in mouse brain tissue were measured. Numbers of mouth-opening breaths of the isolated mouse head were observed in acute cerebral ischemia mice.RESULTS Learning and memory ability in mice with RCBE were improved significantly compared with model group. The activity of SOD,Na^+-K^+-ATPase and Ca^(2+)-ATPase were increased,while MDA contents decreased after RCBE(0.5,1.0 and 2.0 g·kg^(-1)) and piracetam(0.5 g·kg^(-1)) treatment compared with the model group. RCBE at all concentrations significantly prolonged the number of mouth-opening breaths of the isolated mouse head. CONCLUSION RCBE preconditioning exerts a marked neuroprotective effect on the ischemia brain,which is related to improve the learning and memory via regulating energy metabolism and anti-oxidation.展开更多
OBJECTIVE Astrocytic gap junctions formed by connexin 43(Cx43) are crucial for intercellular communication between spinal cord astrocytes. Various neurological disorders include chronic pain are associated with dysfun...OBJECTIVE Astrocytic gap junctions formed by connexin 43(Cx43) are crucial for intercellular communication between spinal cord astrocytes. Various neurological disorders include chronic pain are associated with dysfunctional Cx43-gap junctions. A previous study showed that treatment of spinal astrocytes in culture with pro-inflammatory cytokines tumor necrosis factor-α(TNF-α) and interferon-γ(IFN-γ) decreased both Cx43 expression and gap junction intercellular communication(GJIC)via a c-jun terminal kinase-dependent pathway. However,the exact mechanism that Cx43 does this in the context of spinal astrocytic dysfunction is unclear. The current study investigated the downstream signaling of Cx43-gap junction in rat primary cultured spinal astrocytes stimulated with cytokines.METHODS Wefocused on the glutamate transporters,examined the alteration of GLT-1 and glutamate-aspartate transporter(GLAST)expression and function in rat primary cultured spinal astrocytes stimulated with cytokines by real-time PCR and Western blotting. The function of GLT-1 was analyzed using the carbon 14. To elucidate the effect of Cx43 on glutamate transporters in spinal astrocytes,changes in glutamate transporters expression and function were quantified after Cx43 siRNA treatment.RESULTS The transcriptional and translational levels of Cx43 were reduced after 12 hr co-treatment with TNF-α(10 ng·mL^(-1)) or IFN-γ(5 ng·mL^(-1)). Furthermore,transcriptional and translational levels of GLT-1 and GLAST were also significantly reduced 24 and 48 h co-treatment with TNF-α or IFN-γ.Moreover,functional GLT-1 and GLAST uptake were inhibited by the mixture of TNF-α and IFN-γ. In addition,Both the decrease of GLT-1 expression and the reduction in functional GLT-1 uptake induced by the Cx43 si RNA,but both the expression and functional GLAST were no changes. CONCLUSION These results indicate that a Cx43 downregulation is induced under inflammatory condition that disrupts spinal astrocytic GLT-1 expression and function,leading to astrocytic dysfunction and the maintenance of the neuroinflammatory state.展开更多
OBJECTIVE Cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling has been shown to regulate alcohol consumption.The phosphodiesterase 7(PDE7)enzyme is one of the PDE families responsible for controlling i...OBJECTIVE Cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling has been shown to regulate alcohol consumption.The phosphodiesterase 7(PDE7)enzyme is one of the PDE families responsible for controlling intracellular levels of cAMP.However,the role of PDE7 in alcohol consump⁃tion remains unknown.C57BL/6J(B6)mice innately consume larger amounts of alcohol while DBA/2J(DBA)mice do the opposite,ie,they drink little alcohol.In the present study,we evaluated whether PDE7 plays a role in regulat⁃ing alcohol intake using adult B6 and DBA mice.METHODS Adult male B6 and DBA mice were tested for ethanol(7%and 10%,V/V)intake and preference using the two-bottle choice task.In addition,a separate set of B6 and DBA mice was examined for PDE7 expression in the striatum,a brain region critical for ethanol drinking,using Western blotting.Further,PDE7 subtype expres⁃sion in the striatum of B6 mice in response to ethanol drinking was examined.Finally,the effect of the PDE7 inhibitor BRL-50481 on etha⁃nol consumption was examined in B6 mice.RESULTS①Comparison of ethanol drinking behavior between B6 and DBA mice.Compared to DBA mice,B6 mice had significantly higher ethanol intake and preference,without altering sucrose intake and preference or quinine intake and preference.②Comparison of the expres⁃sion of PDE7 subtypes in the brain striatum of B6 and DBA mice.Compared to DBA mice,naive B6 mice showed significant lower expres⁃sion of PDE7A(P<0.01),but not PDE7B in the striatum.③PDE7A in the striatum of naive and ethanol-drinking B6 mice.After ethanol drinking for 10 d,B6 mice showed significant increases in expression of PDE7A in the striatum(P<0.01)relative to naive controls,but no changes in PDE7B.④Effect of BRL-50481 on ethanol drinking behavior in B6 mice.BRL-50481(0.3-3 mf·kg-1)reduced ethanol intake(P<0.01 for 0.3 and 1 mg·kg-1;P<0.05 for 3 mg·kg-1)and preference(P<0.05 for all doses)without altering the total fluid intake in B6 mice.CON⁃CLUSION PDE7A expression is relatively high in the striatum of alcohol preferring mice such as B6 and can be further increased following etha⁃nol drinking.PDE7A is an important player in the regulation of alcohol consumption.Drugs inhibiting PDE7A can be novel treatments for alcoholism.展开更多
Objective:To observe the effects of biochanin A on learning and memory of ovariectomized rats and the histopathological changes in uterus and breast tissues,so as to look for a new drug instead of estradiol to prevent...Objective:To observe the effects of biochanin A on learning and memory of ovariectomized rats and the histopathological changes in uterus and breast tissues,so as to look for a new drug instead of estradiol to prevent or treat neuro-degenerative diseases after menopause.Method:A total of 48 six-month-old female rats were randomly divided into six groups:sham group,model group,17β-estrodiol,Biochanin A high-dose group,middle-dose group and low-dose group.The changes of the spatial learning and memory function were observed through Morris water maze.After the treatment,morphous of the hippocampus were observed after HE stained by microscope.Internal structure of hippocampal neurons was observed under transmission electron microscope.Colorimetry method was used to test SOD and GSH-PX activity and MDA content in the left cerebral homogenate.Western Blot was used to examine the expression of PPAR gamma and MMP-2 in right hippocampus of rats.After the treatment,the histopathological changes in uterus and breast tissues were observed to probe its safety for therapy.Result:Biochanin A could significantly antagonize the decrease of spatial learning and memory induced by OVX.Under the optical microscope and Electron microscopy observation,The number of necrosis nerve cells in Biochanin A treatment groups were significantly reduced.Biochanin A groups could decrease the content of MDA,and increase the activity of GSH-PX,SOD.The expression of PPAR gamma was down regulated and the expression of MMP-2 was up regulated in Biochanin A groups.The number of acini decreased,tissue atrophy in model group,low-dose group and middle-dose group,but the situatiion reserved in high-dose group.Conclusion:Biochanin A could significantly improve memory dysfunction due to lower estrogen levels in rats,the mechanism of which may be related to antioxidative stress.展开更多
Background and Objective:Increased blood pressure variability(BPV),which has been considered to cause brain damage,can be induced by sinoaortic denervation(SAD)in rats.This study was designed to test the hypothesis th...Background and Objective:Increased blood pressure variability(BPV),which has been considered to cause brain damage,can be induced by sinoaortic denervation(SAD)in rats.This study was designed to test the hypothesis that increased BPV impairs learning and memory in rats with SAD.Methods:SAD was performed in male Sprague-Dawley rats.Passive avoidance trial was used to evaluate learning and memory ability.Results:Compared with shamoperated(Sham)group,there was no significant difference in the latency of passive avoidance in adaption trial.The latency of avoiding darkness in retention trial in SAD group was significantly lower than that in Sham group both 2 and 16 weeks after SAD(P<0.05,P<0.01).Westernblot assay revealed that all the expression of choline acetyltransferase,vesicular acetylcholine transporter andα7 nicotinic acetylcholine receptor decreaed in both cerebral cortex(P<0.05)and hippocampus(P<0.05)16 weeks after SAD(P<0.05),while only level ofα7 nicotinic acetylcholine receptor was reduced in hippocampus 2 weeks after SAD(P<0.05).Conclusion:Increasd BPV reduces memory ability in SAD rats,potentially through cholinergic pathway.展开更多
Objective:To observe the effects of estrogen/plant estrogen(Biochanin A,BCA)on learning and memory of ovariectomized rats,so as to explore the possible mechanisms of neuroprotective effect on endogenous growth hormone...Objective:To observe the effects of estrogen/plant estrogen(Biochanin A,BCA)on learning and memory of ovariectomized rats,so as to explore the possible mechanisms of neuroprotective effect on endogenous growth hormone.Method:A total of 50 six-month-old female rats were randomly divided into five groups:sham group,model group,17β-estrodiol,Biochanin A high-dose group,and low-dose group.The changes of the spatial learning and memory function were observed through Morris water maze and shuttle box.After the treatment,morphological structures of rat neurons were observed by HE staining and electron microscopy.The contents of E2 and GH in serum were determined by ELISA and associated proteins of growth hormone JAK/STAT signaling pathway were examined by western blot.Result:Estrogen/BCA could enhance learning and memory ability of the aging rats,improve the structures of the nerve cells,increase E2,GH and IGF1 levels,improve STAT5 and p-STAT5 protein expression and reduce SOCS2 protein expression.Conclusion:Estrogen/BCA could significantly improve memory dysfunction,the mechanisms may be related to increase secretion of endogenous growth hormone,regulate growth hormone JAK/STAT signaling pathway.展开更多
Background:Phosphodiesterase 4(PDE4),one of the 11 PDE enzyme families that hydrolyze cyclic nucleotides,is critical for controlling intracellular cyclic AMP(cAMP)concentrations and plays an important role in regulati...Background:Phosphodiesterase 4(PDE4),one of the 11 PDE enzyme families that hydrolyze cyclic nucleotides,is critical for controlling intracellular cyclic AMP(cAMP)concentrations and plays an important role in regulating alcohol consumption and mediating memory in dementia such as Alzheimer’s disease(AD).Chronic alcohol consumption can cause alcohol-related dementia and 50%~75%of detoxified alcoholics have memory or cognition impairment.However,the role of PDE4 and its mechanism remain to be characterized and elucidated.Methods:Using the water-maze,passive avoidance,or novel object recognition test,we examined the effects of rolipram,a prototypical PDE4 inhibitor,and roflumilast,a potent PDE4 inhibitor which has been approved for treatment of chronic obstructive pulmonary disease(COPD)in humans,on memory loss in APP/PS1 double transgenic mice,a widely used model for AD.In addition,we tested the effects of the PDE4 inhibitors,via ip,intra-gastric,or intrastriatum infusion,on ethanol intake and preference using the mouse two-bottle choice paradigm.Mice deficient in PDE4A,PDE4B,or PDE4D(4AKO,4BKO,and 4DKO,respectively)and their wild type(WT)controls were tested for ethanol consumption and memory;the latter was measured in the absence or presence of beta-amyloid peptide 1-42(Abeta42)infused into the dorsal hippocampus.Results:Similar to rolipram,roflumilast reversed memory deficits in APP/PS1 mice in all the memory tests and reduced ethanol intake and preference in C57BL/6 mice in two-bottle choice.Consistent with the results in the memory tests,roflumilast reduced the loss of neurons and neurocyte apoptosis in AD mice,as shown using HE and Nissl staining.It also reversed the decreased ratio of Bcl-2/BAX in the cerebral cortex and hippocampus of AD mice.In addition,roflumilast reversed the decreased levels of cAMP and expression of phosphorylated cAMP response element-binding protein(CREB)and brain derived neurotrophic factor(BDNF)in AD mice.Compared to the WT controls,4AKO mice displayed significant decreases in ethanol intake and preference and reversal of Abeta42-induced memory deficits.In contrast,4BKO mice only mimicked the ability of 4AKO mice to reduce alcohol consumption while 4DKO mice only to reverse Abeta42-induced memory deficits.In addition,levels of cAMP and phospho-CREB(pCREB)were increased in the hippocampus of 4AKO or 4DKO mice,which also showed reversal of Abeta42-induced decreases in pCREB.Conclusions:These data suggest that PDE4 inhibitors such as roflumilast improve learning and memory in AD and reduce ethanol intake and preference likely via cAMP/CREB/BDNF signaling-mediated neuroprotection.PDE4 isoforms have different roles in mediating ethanol-drinking behavior and memory in AD.The results indicate PDE4A as a potential new target for alcohol-related dementia,although studies with animal models of alcoholrelated dementia are needed to clarify this.展开更多
Objective:To investigate the neuroprotective effects of estradiol(E2)may be related to the interact with Grow Hormone(GH).Method:The protective effect of GH in different dose level(5,25,125,250,500 ng·mL-1)was ob...Objective:To investigate the neuroprotective effects of estradiol(E2)may be related to the interact with Grow Hormone(GH).Method:The protective effect of GH in different dose level(5,25,125,250,500 ng·mL-1)was observed in primary culture of rat hippocampal neurons for 24 hours through CCK-8 colorimetry.Phosphorylated-STAT5(P-STAT5)and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with different doses of GH(0.1~20 ng·mL-1),or different time of GH(15~90 min)to observe GH the optimal concentration and action time.SOCS2 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with different doses of E2(10-11~10-7 mol·L-1),or different time of E2(15~90 min)to observe E2 the optimal concentration and action time.P-STAT5 and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with GH(5 ng·mL-1),or E2(10-8 mol·L-1),or E2+GH.In this latter case E2 was added 60 min before GH.SOCS1,SOCS2 and SOCS3 mRNA and protein levels were detected in 24 h serum starved rat hippocampal neurons after 60 min treatment with E2(10-8 mol·L-1).SOCS2 mRNA and protein levels were detected in 24 h serum starved rat hippocampal neurons after 60 min treatment with GH(5 ng·mL-1),or E2(10-8 mol·L-1),or E2+GH.In this latter case E2 was added 60 min before GH.Result:It was testified that GH was nontoxic to rat hippocampal neurons in the range of 5~250 ng·mL-1.However,if GH concentration was over 250 ng·mL-1,the activity of hippocampal neurons began to decrease.STAT5 and P-STAT5 protein levels were response to increasing concentrations of GH(0.1~20 ng·mL-1)in rat hippocampal neurons after 60 min of treatment,which determined optimal concentration and effect time of GH.SOCS2 protein levels were response to increasing concentrations of E2(10-11~10-7 mol·L-1)in rat hippocampal neurons after 60 min of treatment,which determined optimal concentration and effect time of E2.P-STAT5 and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 60 min GH(5 ng·mL-1)or E2(10-8 mol·L-1)treatment.For the combined treatment with the two hormones,E2 pretreatment(10-8 mol·L-1)60 min before GH induced a significant increase of P-STAT5 and STAT5 compared with GH alone.Treatment for 60 min with E2(10-8 mol·L-1)did not modify neither protein levels nor RNAs of SOCS1 and SOCS3 in rat hippocampal neurons,while E2 significantly reduced SOCS2 protein level without affecting its mRNA level.Neither 60 min treatment with GH(5 ng·mL-1)or E2(10-8 mol·L-1)nor the combined treatment with the two hormones induced any modifi cation of SOCS2 mRNA,whereas E2 pretreatment 60 min before GH was able to induce a signifi cant reduction of SOCS2 protein levels.Conclusion:E2 amplifies intracellular GH signaling by favoring SOCS2 degradation through the proteasome machinery.展开更多
基金The project supported by Medical Science and Technology Development Plan of Shandong Province(2016WS0611)Science and Technology Development Plan of Tai'an City(2016NS1070)
文摘OBJECTIVE To investigate the effects of Radix Cynanchum bungei extract(RCBE) on cerebral ischemia-reperfusion(I/R) and acute cerebral ischemia induced impairment in mice.METHODS I/R model was induced by bilateral carotid artery occlusion(BCAO)-reperfusion method and Y-maze learning and memory performance was assessed after reperfusion. Na^+-K^+-ATPase,Ca^(2+)-ATPase and SOD activity,as well as MDA content in mouse brain tissue were measured. Numbers of mouth-opening breaths of the isolated mouse head were observed in acute cerebral ischemia mice.RESULTS Learning and memory ability in mice with RCBE were improved significantly compared with model group. The activity of SOD,Na^+-K^+-ATPase and Ca^(2+)-ATPase were increased,while MDA contents decreased after RCBE(0.5,1.0 and 2.0 g·kg^(-1)) and piracetam(0.5 g·kg^(-1)) treatment compared with the model group. RCBE at all concentrations significantly prolonged the number of mouth-opening breaths of the isolated mouse head. CONCLUSION RCBE preconditioning exerts a marked neuroprotective effect on the ischemia brain,which is related to improve the learning and memory via regulating energy metabolism and anti-oxidation.
文摘OBJECTIVE Astrocytic gap junctions formed by connexin 43(Cx43) are crucial for intercellular communication between spinal cord astrocytes. Various neurological disorders include chronic pain are associated with dysfunctional Cx43-gap junctions. A previous study showed that treatment of spinal astrocytes in culture with pro-inflammatory cytokines tumor necrosis factor-α(TNF-α) and interferon-γ(IFN-γ) decreased both Cx43 expression and gap junction intercellular communication(GJIC)via a c-jun terminal kinase-dependent pathway. However,the exact mechanism that Cx43 does this in the context of spinal astrocytic dysfunction is unclear. The current study investigated the downstream signaling of Cx43-gap junction in rat primary cultured spinal astrocytes stimulated with cytokines.METHODS Wefocused on the glutamate transporters,examined the alteration of GLT-1 and glutamate-aspartate transporter(GLAST)expression and function in rat primary cultured spinal astrocytes stimulated with cytokines by real-time PCR and Western blotting. The function of GLT-1 was analyzed using the carbon 14. To elucidate the effect of Cx43 on glutamate transporters in spinal astrocytes,changes in glutamate transporters expression and function were quantified after Cx43 siRNA treatment.RESULTS The transcriptional and translational levels of Cx43 were reduced after 12 hr co-treatment with TNF-α(10 ng·mL^(-1)) or IFN-γ(5 ng·mL^(-1)). Furthermore,transcriptional and translational levels of GLT-1 and GLAST were also significantly reduced 24 and 48 h co-treatment with TNF-α or IFN-γ.Moreover,functional GLT-1 and GLAST uptake were inhibited by the mixture of TNF-α and IFN-γ. In addition,Both the decrease of GLT-1 expression and the reduction in functional GLT-1 uptake induced by the Cx43 si RNA,but both the expression and functional GLAST were no changes. CONCLUSION These results indicate that a Cx43 downregulation is induced under inflammatory condition that disrupts spinal astrocytic GLT-1 expression and function,leading to astrocytic dysfunction and the maintenance of the neuroinflammatory state.
基金National Natural Science Foundation of China(81773717)National Natural Science Foundation of China(81801510)+1 种基金Academic Promotion Program of Shandong First Medical University(2019QL011)and Science and Technology Development Plan Project in Tai′an City(2017NS0237).
文摘OBJECTIVE Cyclic adenosine monophosphate(cAMP)-protein kinase A(PKA)signaling has been shown to regulate alcohol consumption.The phosphodiesterase 7(PDE7)enzyme is one of the PDE families responsible for controlling intracellular levels of cAMP.However,the role of PDE7 in alcohol consump⁃tion remains unknown.C57BL/6J(B6)mice innately consume larger amounts of alcohol while DBA/2J(DBA)mice do the opposite,ie,they drink little alcohol.In the present study,we evaluated whether PDE7 plays a role in regulat⁃ing alcohol intake using adult B6 and DBA mice.METHODS Adult male B6 and DBA mice were tested for ethanol(7%and 10%,V/V)intake and preference using the two-bottle choice task.In addition,a separate set of B6 and DBA mice was examined for PDE7 expression in the striatum,a brain region critical for ethanol drinking,using Western blotting.Further,PDE7 subtype expres⁃sion in the striatum of B6 mice in response to ethanol drinking was examined.Finally,the effect of the PDE7 inhibitor BRL-50481 on etha⁃nol consumption was examined in B6 mice.RESULTS①Comparison of ethanol drinking behavior between B6 and DBA mice.Compared to DBA mice,B6 mice had significantly higher ethanol intake and preference,without altering sucrose intake and preference or quinine intake and preference.②Comparison of the expres⁃sion of PDE7 subtypes in the brain striatum of B6 and DBA mice.Compared to DBA mice,naive B6 mice showed significant lower expres⁃sion of PDE7A(P<0.01),but not PDE7B in the striatum.③PDE7A in the striatum of naive and ethanol-drinking B6 mice.After ethanol drinking for 10 d,B6 mice showed significant increases in expression of PDE7A in the striatum(P<0.01)relative to naive controls,but no changes in PDE7B.④Effect of BRL-50481 on ethanol drinking behavior in B6 mice.BRL-50481(0.3-3 mf·kg-1)reduced ethanol intake(P<0.01 for 0.3 and 1 mg·kg-1;P<0.05 for 3 mg·kg-1)and preference(P<0.05 for all doses)without altering the total fluid intake in B6 mice.CON⁃CLUSION PDE7A expression is relatively high in the striatum of alcohol preferring mice such as B6 and can be further increased following etha⁃nol drinking.PDE7A is an important player in the regulation of alcohol consumption.Drugs inhibiting PDE7A can be novel treatments for alcoholism.
文摘Objective:To observe the effects of biochanin A on learning and memory of ovariectomized rats and the histopathological changes in uterus and breast tissues,so as to look for a new drug instead of estradiol to prevent or treat neuro-degenerative diseases after menopause.Method:A total of 48 six-month-old female rats were randomly divided into six groups:sham group,model group,17β-estrodiol,Biochanin A high-dose group,middle-dose group and low-dose group.The changes of the spatial learning and memory function were observed through Morris water maze.After the treatment,morphous of the hippocampus were observed after HE stained by microscope.Internal structure of hippocampal neurons was observed under transmission electron microscope.Colorimetry method was used to test SOD and GSH-PX activity and MDA content in the left cerebral homogenate.Western Blot was used to examine the expression of PPAR gamma and MMP-2 in right hippocampus of rats.After the treatment,the histopathological changes in uterus and breast tissues were observed to probe its safety for therapy.Result:Biochanin A could significantly antagonize the decrease of spatial learning and memory induced by OVX.Under the optical microscope and Electron microscopy observation,The number of necrosis nerve cells in Biochanin A treatment groups were significantly reduced.Biochanin A groups could decrease the content of MDA,and increase the activity of GSH-PX,SOD.The expression of PPAR gamma was down regulated and the expression of MMP-2 was up regulated in Biochanin A groups.The number of acini decreased,tissue atrophy in model group,low-dose group and middle-dose group,but the situatiion reserved in high-dose group.Conclusion:Biochanin A could significantly improve memory dysfunction due to lower estrogen levels in rats,the mechanism of which may be related to antioxidative stress.
基金This work was supported by the Natural Science Foundation of Shandong Province of China(ZR2014HQ007,ZR2017MH048),the Foundation of Overseas Distinguished Taishan Scholars of Shandong Province of China(to H-TZ)and Collaborative Innovation Center for Research and Development of Traditional Chinese Medicine in Mount Tai.
文摘Background and Objective:Increased blood pressure variability(BPV),which has been considered to cause brain damage,can be induced by sinoaortic denervation(SAD)in rats.This study was designed to test the hypothesis that increased BPV impairs learning and memory in rats with SAD.Methods:SAD was performed in male Sprague-Dawley rats.Passive avoidance trial was used to evaluate learning and memory ability.Results:Compared with shamoperated(Sham)group,there was no significant difference in the latency of passive avoidance in adaption trial.The latency of avoiding darkness in retention trial in SAD group was significantly lower than that in Sham group both 2 and 16 weeks after SAD(P<0.05,P<0.01).Westernblot assay revealed that all the expression of choline acetyltransferase,vesicular acetylcholine transporter andα7 nicotinic acetylcholine receptor decreaed in both cerebral cortex(P<0.05)and hippocampus(P<0.05)16 weeks after SAD(P<0.05),while only level ofα7 nicotinic acetylcholine receptor was reduced in hippocampus 2 weeks after SAD(P<0.05).Conclusion:Increasd BPV reduces memory ability in SAD rats,potentially through cholinergic pathway.
文摘Objective:To observe the effects of estrogen/plant estrogen(Biochanin A,BCA)on learning and memory of ovariectomized rats,so as to explore the possible mechanisms of neuroprotective effect on endogenous growth hormone.Method:A total of 50 six-month-old female rats were randomly divided into five groups:sham group,model group,17β-estrodiol,Biochanin A high-dose group,and low-dose group.The changes of the spatial learning and memory function were observed through Morris water maze and shuttle box.After the treatment,morphological structures of rat neurons were observed by HE staining and electron microscopy.The contents of E2 and GH in serum were determined by ELISA and associated proteins of growth hormone JAK/STAT signaling pathway were examined by western blot.Result:Estrogen/BCA could enhance learning and memory ability of the aging rats,improve the structures of the nerve cells,increase E2,GH and IGF1 levels,improve STAT5 and p-STAT5 protein expression and reduce SOCS2 protein expression.Conclusion:Estrogen/BCA could significantly improve memory dysfunction,the mechanisms may be related to increase secretion of endogenous growth hormone,regulate growth hormone JAK/STAT signaling pathway.
文摘Background:Phosphodiesterase 4(PDE4),one of the 11 PDE enzyme families that hydrolyze cyclic nucleotides,is critical for controlling intracellular cyclic AMP(cAMP)concentrations and plays an important role in regulating alcohol consumption and mediating memory in dementia such as Alzheimer’s disease(AD).Chronic alcohol consumption can cause alcohol-related dementia and 50%~75%of detoxified alcoholics have memory or cognition impairment.However,the role of PDE4 and its mechanism remain to be characterized and elucidated.Methods:Using the water-maze,passive avoidance,or novel object recognition test,we examined the effects of rolipram,a prototypical PDE4 inhibitor,and roflumilast,a potent PDE4 inhibitor which has been approved for treatment of chronic obstructive pulmonary disease(COPD)in humans,on memory loss in APP/PS1 double transgenic mice,a widely used model for AD.In addition,we tested the effects of the PDE4 inhibitors,via ip,intra-gastric,or intrastriatum infusion,on ethanol intake and preference using the mouse two-bottle choice paradigm.Mice deficient in PDE4A,PDE4B,or PDE4D(4AKO,4BKO,and 4DKO,respectively)and their wild type(WT)controls were tested for ethanol consumption and memory;the latter was measured in the absence or presence of beta-amyloid peptide 1-42(Abeta42)infused into the dorsal hippocampus.Results:Similar to rolipram,roflumilast reversed memory deficits in APP/PS1 mice in all the memory tests and reduced ethanol intake and preference in C57BL/6 mice in two-bottle choice.Consistent with the results in the memory tests,roflumilast reduced the loss of neurons and neurocyte apoptosis in AD mice,as shown using HE and Nissl staining.It also reversed the decreased ratio of Bcl-2/BAX in the cerebral cortex and hippocampus of AD mice.In addition,roflumilast reversed the decreased levels of cAMP and expression of phosphorylated cAMP response element-binding protein(CREB)and brain derived neurotrophic factor(BDNF)in AD mice.Compared to the WT controls,4AKO mice displayed significant decreases in ethanol intake and preference and reversal of Abeta42-induced memory deficits.In contrast,4BKO mice only mimicked the ability of 4AKO mice to reduce alcohol consumption while 4DKO mice only to reverse Abeta42-induced memory deficits.In addition,levels of cAMP and phospho-CREB(pCREB)were increased in the hippocampus of 4AKO or 4DKO mice,which also showed reversal of Abeta42-induced decreases in pCREB.Conclusions:These data suggest that PDE4 inhibitors such as roflumilast improve learning and memory in AD and reduce ethanol intake and preference likely via cAMP/CREB/BDNF signaling-mediated neuroprotection.PDE4 isoforms have different roles in mediating ethanol-drinking behavior and memory in AD.The results indicate PDE4A as a potential new target for alcohol-related dementia,although studies with animal models of alcoholrelated dementia are needed to clarify this.
文摘Objective:To investigate the neuroprotective effects of estradiol(E2)may be related to the interact with Grow Hormone(GH).Method:The protective effect of GH in different dose level(5,25,125,250,500 ng·mL-1)was observed in primary culture of rat hippocampal neurons for 24 hours through CCK-8 colorimetry.Phosphorylated-STAT5(P-STAT5)and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with different doses of GH(0.1~20 ng·mL-1),or different time of GH(15~90 min)to observe GH the optimal concentration and action time.SOCS2 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with different doses of E2(10-11~10-7 mol·L-1),or different time of E2(15~90 min)to observe E2 the optimal concentration and action time.P-STAT5 and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 24 h of serum starvation and treated for 60 min with GH(5 ng·mL-1),or E2(10-8 mol·L-1),or E2+GH.In this latter case E2 was added 60 min before GH.SOCS1,SOCS2 and SOCS3 mRNA and protein levels were detected in 24 h serum starved rat hippocampal neurons after 60 min treatment with E2(10-8 mol·L-1).SOCS2 mRNA and protein levels were detected in 24 h serum starved rat hippocampal neurons after 60 min treatment with GH(5 ng·mL-1),or E2(10-8 mol·L-1),or E2+GH.In this latter case E2 was added 60 min before GH.Result:It was testified that GH was nontoxic to rat hippocampal neurons in the range of 5~250 ng·mL-1.However,if GH concentration was over 250 ng·mL-1,the activity of hippocampal neurons began to decrease.STAT5 and P-STAT5 protein levels were response to increasing concentrations of GH(0.1~20 ng·mL-1)in rat hippocampal neurons after 60 min of treatment,which determined optimal concentration and effect time of GH.SOCS2 protein levels were response to increasing concentrations of E2(10-11~10-7 mol·L-1)in rat hippocampal neurons after 60 min of treatment,which determined optimal concentration and effect time of E2.P-STAT5 and STAT5 protein levels were tested in primary culture of rat hippocampal neurons after 60 min GH(5 ng·mL-1)or E2(10-8 mol·L-1)treatment.For the combined treatment with the two hormones,E2 pretreatment(10-8 mol·L-1)60 min before GH induced a significant increase of P-STAT5 and STAT5 compared with GH alone.Treatment for 60 min with E2(10-8 mol·L-1)did not modify neither protein levels nor RNAs of SOCS1 and SOCS3 in rat hippocampal neurons,while E2 significantly reduced SOCS2 protein level without affecting its mRNA level.Neither 60 min treatment with GH(5 ng·mL-1)or E2(10-8 mol·L-1)nor the combined treatment with the two hormones induced any modifi cation of SOCS2 mRNA,whereas E2 pretreatment 60 min before GH was able to induce a signifi cant reduction of SOCS2 protein levels.Conclusion:E2 amplifies intracellular GH signaling by favoring SOCS2 degradation through the proteasome machinery.
