Notch pathway activation maintains neural stem cells in a proliferating state and increases nerve repair capacity. To date, studies have rarely focused on changes or damage to signal transduc- tion pathways during cer...Notch pathway activation maintains neural stem cells in a proliferating state and increases nerve repair capacity. To date, studies have rarely focused on changes or damage to signal transduc- tion pathways during cerebral hemorrhage. Here, we examined the effect of acupuncture in a rat model of cerebral hemorrhage. We examined four groups： in the control group, rats received no treatment. In the model group, cerebral hemorrhage models were established by infusing non-hep-arinized blood into the Brain. In the acupuncture group, modeled rats had Baihui （DU20） and Qubin （GBT） acupoints treated once a day for 30 minutes. In the DAPT group, modeled rats had 0.15 μg/mL DAPT solution （10 mL） infused into the brain. Immunohistochemistry and western blot results showed that acupuncture effectively inhibits Notch 1 and Hesl protein expression in rat basal ganglia. These inhibitory effects were identical to DAPT, a Notch signaling pathway inhibitor. Our results suggest that acupuncture has a neuroprotective effect on cerebral hemorrhage by in- hibiting Notch-Hes signaling pathway transduction in rat basal ganglia after cerebral hemorrhage.展开更多
As an inhibitor of the Notch signaling pathway, N-[N-(3,5-difluorohenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester(DAPT) may protect brain tissue from serious ischemic injury. This study aimed to explore neuropro...As an inhibitor of the Notch signaling pathway, N-[N-(3,5-difluorohenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester(DAPT) may protect brain tissue from serious ischemic injury. This study aimed to explore neuroprotection by DAPT after cerebral ischemia/reperfusion(I/R) injury. DAPT was intraperitoneally injected 3 hours before the establishment of a focal cerebral I/R model in the right middle cerebral artery of obstructed mice. Longa scores were used to assess neurological changes of mice. Nissl staining and TdT-mediated dUTP-biotin nick-end labeling staining were used to examine neuronal damage and cell apoptosis in the right prefrontal cortex, while immunofluorescence staining was used to detect glial fibrillary acidic protein-and Notch1-positive cells. Protein expression levels of Hes1 and Hes5 were detected by western blot assay in the right prefrontal cortex. Our results demonstrated that DAPT significantly improved neurobehavioral scores and relieved neuronal morphological damage. DAPT decreased the number of glial fibrillary acidic protein-and Notch1-positive cells in the right prefrontal cortex, while also reducing the number of apoptotic cells and decreasing interleukin-6 and tumor necrosis factor-α contents, and simultaneously downregulating Hes1 and Hes5 protein expression. These findings verify that DAPT alleviates pathological lesions and strengthens the anti-inflammatory response after cerebral I/R injury. Thus, DAPT might be developed as an effective drug for the prevention of cerebral I/R injury.展开更多
Background Brain dysfunction is a frequent complication of sepsis,usually defined as sepsis-associated encephalopathy （SAE）.Although the Notch signaling pathway has been proven to be involved in both ischemia and ne...Background Brain dysfunction is a frequent complication of sepsis,usually defined as sepsis-associated encephalopathy （SAE）.Although the Notch signaling pathway has been proven to be involved in both ischemia and neuronal proliferation,its role in SAE is still unknown.Here,the effect of the Notch signaling pathway involved γ-secretase inhibitor DAPT on SAE in septic rats was investigated in a cecal ligation and puncture （CLP） model.Methods Fifty-nine Sprague-Dawley rats were randomly divided into four groups,with the septic group receiving the CLP operation.Twenty-four hours after CLP or sham treatment,rats were sacrificed and their hippocampus was harvested for Western blot analysis.TNF-αexpression was determined using an enzyme-linked immunosorbent assay （ELISA） kit.Neuronal apoptosis was assessed by TUNEL staining,and neuronal cell death was detected by H＆E staining.Finally,a novel object recognition experiment was used to evaluate memory impairment.Results Our data showed that sepsis can increase the expression of hippocampal Notch receptor intracellular domain （NICD） and poly （adenosine diphosphate [ADP]-ribose） polymerase-1 （PARP-1）,as well as the inflammatory response,neuronal apoptosis,neuronal death,and memory dysfunction in rats.The γ-secretase inhibitor N-[N-（3,5-difluorophenacetyl）-1-alanyl]-S-phenylglycine t-butyl ester （DAPT） can significantly decrease the level of NICD and PARP-1,reduce hippocampal neuronal apoptosis and death,attenuate TNF-α release and rescue cognitive impairment caused by CLP.Conclusion The neuroprotective effect of DAPT on neuronal death and memory impairment in septic rats,which could be a new therapeutic approach for treating SAE in the future.展开更多
Aim To investigate the effect of DAPT （γ-secretase inhibitor） on the growth of human tongue carcinoma cells and to determine the molecular mechanism to enable the potential application of DAPT to the treatment of t...Aim To investigate the effect of DAPT （γ-secretase inhibitor） on the growth of human tongue carcinoma cells and to determine the molecular mechanism to enable the potential application of DAPT to the treatment of tongue carcinoma. Methodology Human tongue carcinoma Tca8113 cells were cultured with DAPT. Cell growth was determined using Indigotic Reduction method. The cell cycle and apoptosis were analyzed by flow cytometry. Real-time PCR and Immuno-Fluorescence （IF） were employed to determine the intracellular expression levels. Results DAPT inhibited the growth of human tongue carcinoma Tca8113 cells by inducing G0-G1 cell cycle arrest and apoptosis, The mRNA levels of Hairy/Enhancer of Split-1 （Hes-1）, a target of Notch activation, were reduced by DAPT in a dose-dependent manner. Coincident with this observation, DAPT induced a dose-dependent promotion of constitutive Caspase-3 in Tca8113 cells. Conclusion DAPT may have a therapeutic value for human tongue carcinoma. Moreover, the effects of DAPT in tumor inhibition may arise partly via the modulation of Notch- 1 and Caspase-3.展开更多
Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regenera...Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased. Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.展开更多
基金supported by the National Natural Science Foundation of China,No.81273824,30772840Ministry of Education Doctoral Fund in China,No.20102327110003+1 种基金the Natural Science Foundation of Heilongjiang Province in China,No.ZD201204Special funds for Technological Innovation Research of Harbin,China,No.2012RFXXS062
文摘Notch pathway activation maintains neural stem cells in a proliferating state and increases nerve repair capacity. To date, studies have rarely focused on changes or damage to signal transduc- tion pathways during cerebral hemorrhage. Here, we examined the effect of acupuncture in a rat model of cerebral hemorrhage. We examined four groups： in the control group, rats received no treatment. In the model group, cerebral hemorrhage models were established by infusing non-hep-arinized blood into the Brain. In the acupuncture group, modeled rats had Baihui （DU20） and Qubin （GBT） acupoints treated once a day for 30 minutes. In the DAPT group, modeled rats had 0.15 μg/mL DAPT solution （10 mL） infused into the brain. Immunohistochemistry and western blot results showed that acupuncture effectively inhibits Notch 1 and Hesl protein expression in rat basal ganglia. These inhibitory effects were identical to DAPT, a Notch signaling pathway inhibitor. Our results suggest that acupuncture has a neuroprotective effect on cerebral hemorrhage by in- hibiting Notch-Hes signaling pathway transduction in rat basal ganglia after cerebral hemorrhage.
基金supported by the National Natural Science Foundation of China,No.81660243(to JDZ)a grant from the Social Development Science and Technology Plan Project of Science and Technology Department of Guizhou Province of China,No.SY [2015] 3041(to JDZ)a grant from the Science and Technology Department of Guizhou Province of China,No.LG [2012] 028(to JDZ)
文摘As an inhibitor of the Notch signaling pathway, N-[N-(3,5-difluorohenacetyl)-l-alanyl]-S-phenylglycine tert-butyl ester(DAPT) may protect brain tissue from serious ischemic injury. This study aimed to explore neuroprotection by DAPT after cerebral ischemia/reperfusion(I/R) injury. DAPT was intraperitoneally injected 3 hours before the establishment of a focal cerebral I/R model in the right middle cerebral artery of obstructed mice. Longa scores were used to assess neurological changes of mice. Nissl staining and TdT-mediated dUTP-biotin nick-end labeling staining were used to examine neuronal damage and cell apoptosis in the right prefrontal cortex, while immunofluorescence staining was used to detect glial fibrillary acidic protein-and Notch1-positive cells. Protein expression levels of Hes1 and Hes5 were detected by western blot assay in the right prefrontal cortex. Our results demonstrated that DAPT significantly improved neurobehavioral scores and relieved neuronal morphological damage. DAPT decreased the number of glial fibrillary acidic protein-and Notch1-positive cells in the right prefrontal cortex, while also reducing the number of apoptotic cells and decreasing interleukin-6 and tumor necrosis factor-α contents, and simultaneously downregulating Hes1 and Hes5 protein expression. These findings verify that DAPT alleviates pathological lesions and strengthens the anti-inflammatory response after cerebral I/R injury. Thus, DAPT might be developed as an effective drug for the prevention of cerebral I/R injury.
文摘Background Brain dysfunction is a frequent complication of sepsis,usually defined as sepsis-associated encephalopathy （SAE）.Although the Notch signaling pathway has been proven to be involved in both ischemia and neuronal proliferation,its role in SAE is still unknown.Here,the effect of the Notch signaling pathway involved γ-secretase inhibitor DAPT on SAE in septic rats was investigated in a cecal ligation and puncture （CLP） model.Methods Fifty-nine Sprague-Dawley rats were randomly divided into four groups,with the septic group receiving the CLP operation.Twenty-four hours after CLP or sham treatment,rats were sacrificed and their hippocampus was harvested for Western blot analysis.TNF-αexpression was determined using an enzyme-linked immunosorbent assay （ELISA） kit.Neuronal apoptosis was assessed by TUNEL staining,and neuronal cell death was detected by H＆E staining.Finally,a novel object recognition experiment was used to evaluate memory impairment.Results Our data showed that sepsis can increase the expression of hippocampal Notch receptor intracellular domain （NICD） and poly （adenosine diphosphate [ADP]-ribose） polymerase-1 （PARP-1）,as well as the inflammatory response,neuronal apoptosis,neuronal death,and memory dysfunction in rats.The γ-secretase inhibitor N-[N-（3,5-difluorophenacetyl）-1-alanyl]-S-phenylglycine t-butyl ester （DAPT） can significantly decrease the level of NICD and PARP-1,reduce hippocampal neuronal apoptosis and death,attenuate TNF-α release and rescue cognitive impairment caused by CLP.Conclusion The neuroprotective effect of DAPT on neuronal death and memory impairment in septic rats,which could be a new therapeutic approach for treating SAE in the future.
基金funded by the National Natural Science Foundation of China(30801304)Specialized Research Fund for the Doctoral Program of Higher Education(20070610062)+1 种基金Opening Funding of the State Key Laboratory of Oral Diseases, Sichuan University(SKLOD011)the Applied Fundarmental Project of Sichuan Province(2008 JY0028-2)
文摘Aim To investigate the effect of DAPT （γ-secretase inhibitor） on the growth of human tongue carcinoma cells and to determine the molecular mechanism to enable the potential application of DAPT to the treatment of tongue carcinoma. Methodology Human tongue carcinoma Tca8113 cells were cultured with DAPT. Cell growth was determined using Indigotic Reduction method. The cell cycle and apoptosis were analyzed by flow cytometry. Real-time PCR and Immuno-Fluorescence （IF） were employed to determine the intracellular expression levels. Results DAPT inhibited the growth of human tongue carcinoma Tca8113 cells by inducing G0-G1 cell cycle arrest and apoptosis, The mRNA levels of Hairy/Enhancer of Split-1 （Hes-1）, a target of Notch activation, were reduced by DAPT in a dose-dependent manner. Coincident with this observation, DAPT induced a dose-dependent promotion of constitutive Caspase-3 in Tca8113 cells. Conclusion DAPT may have a therapeutic value for human tongue carcinoma. Moreover, the effects of DAPT in tumor inhibition may arise partly via the modulation of Notch- 1 and Caspase-3.
基金supported by the National Natural Science Foundation of China,No.81420108010,81271084,81200740,81371093
文摘Atoh1 overexpression in cochlear epithelium induces new hair cell formation. Use of adenovirus-mediated Atoh1 overexpression has mainly focused on the rat lesser epithelial ridge and induces ectopic hair cell regeneration. The sensory region of rat cochlea is difficult to transfect, thus new hair cells are rarely produced in situ in rat cochlear explants. After culturing rat cochleae in medium containing 10% fetal bovine serum, adenovirus successfully infected the sensory region as the width of the supporting cell area was significantly increased. Adenovirus encoding Atoh1 infected the sensory region and induced hair cell formation in situ. Combined application of the Notch inhibitor DAPT and Atoh1 increased the Atoh1 expression level and decreased hes1 and hes5 levels, further promoting hair cell generation. Our results demonstrate that DAPT enhances Atoh1 activity to promote hair cell regeneration in rat cochlear sensory epithelium in vitro.
