BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP...BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B （NF- K B） expression in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS： L-NBP （purity 〉 98%） was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide （MTT）, and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS： Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups： the control group, the Aβ1-42 group （2 μmol/L）, the Aβ1-42 ＋ 0.1 μmol/L L-NBP group, the Aβ1-42 ＋ 1 μ mol/L L-NBP group, and the Aβ1-42 ＋ 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 （2 μmol/L） alone or in combination with L-NBP （0.1, 1, 10 μmol/L） for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES： Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS： Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression （P 〈 0.05）. L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression （P 〈 0.05）, and improved cell viability, especially at the high dose （P 〈 0.05）. CONCLUSION： AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.展开更多
AIM To investigate whether glucagon-like peptide-2(GLP-2) influences the neurally-induced responses in gastric strips from mice, since no data are available. METHODS For functional experiments, gastric fundal strips w...AIM To investigate whether glucagon-like peptide-2(GLP-2) influences the neurally-induced responses in gastric strips from mice, since no data are available. METHODS For functional experiments, gastric fundal strips were mounted in organ baths containing Krebs-Henseleit solution. Mechanical responses were recorded via forcedisplacement transducers, which were coupled to a polygraph for continuous recording of isometric tension. Electrical field stimulation(EFS) was applied via two platinum wire rings through which the preparationwas threaded. The effects of GLP-2(2 and 20 nmol/L) were evaluated on the neurally-induced contractile and relaxant responses elicited by EFS. Neuronal nitric oxide synthase(n NOS) enzyme was evaluated by immunohistochemistry.RESULTS In the functional experiments, electrical field stimulation(EFS, 4-16 Hz) induced tetrodotoxin(TTX)-sensitive contractile responses, which were reduced in amplitude by GLP-2(P < 0.05). In the presence of the nitric oxide(NO) synthesis inhibitor L-NNA, GLP-2 no longer influenced the neurally-evoked contractile responses(P > 0.05). The direct smooth muscle response to methacholine was not influenced by GLP-2(P > 0.05). In the presence of guanethidine and carbachol, the addition of GLP-2 to the bath medium evoked TTX-sensitive relaxant responses that were unaffected by L-NNA(P > 0.05). EFS induced a fast NO-mediated relaxation, whose amplitude was enhanced in the presence of the hormone(P < 0.05). Immunohistochemical experiments showed a significant increase(P < 0.05) in n NOS immunoreactivity in the nerve structures after GLP-2 exposure. CONCLUSION The results demonstrate that in gastric fundal strips, GLP-2 influences the amplitude of neurally-induced responses through the modulation of the nitrergic neurotransmission and increases n NOS expression.展开更多
基金Supported by:the Medicine and Health Scientific Research Projects of Shandong Province,No. 2007HZ065
文摘BACKGROUND： L-3-n-butylphthalide （L-NBP） can inhibit phosphorylation of tau protein and reduce the neurotoxicity of beta-amyloid peptide 1-42 （Aβ1-42）. OBJECTIVE： To observe the neuroprotective effects of L-NBP on caspase-3 and nuclear factor kappa-B （NF- K B） expression in a rat model of Alzheimer＇s disease. DESIGN, TIME AND SETTING： A cell experiment was performed at the Central Laboratory of Provincial Hospital affiliated to Shandong University between January 2008 and August 2008. MATERIALS： L-NBP （purity 〉 98%） was provided by Shijiazhuang Pharma Group NBP Pharmaceutical Company Limited. Aβ1-42, 3-[4,5-dimethylthiazolo-2]-2,5 iphenyltetrazolium bromide （MTT）, and rabbit anti-Caspase-3 polyclonal antibody were provided by Cell Signaling, USA; goat anti-choactase and rabbit anti-NF- kB antibodies were provided by Santa Cruz, USA. METHODS： Primary cultures were generated from rat basal forebrain and hippocampal neurons at 17 or 19 days of gestation. The cells were assigned into five groups： the control group, the Aβ1-42 group （2 μmol/L）, the Aβ1-42 ＋ 0.1 μmol/L L-NBP group, the Aβ1-42 ＋ 1 μ mol/L L-NBP group, and the Aβ1-42 ＋ 10μmol/L L-NBP group. The neurons were treated with Aβ1-42 （2 μmol/L） alone or in combination with L-NBP （0.1, 1, 10 μmol/L） for 48 hours. Cells in the control group were incubated in PBS. MAIN OUTCOME MEASURES： Morphologic changes were evaluated using inverted microscopy, viability using the M-I-I- method, and the changes in caspase-3 and NF- k B expression using Western blot. RESULTS： Induction with Aβ1-42 for 48 hours caused cell death and soma atrophy, and increased caspase-3 and NF- K B expression （P 〈 0.05）. L-NBP blocked these changes in cell morphology, decreased caspase-3 and NF- k B expression （P 〈 0.05）, and improved cell viability, especially at the high dose （P 〈 0.05）. CONCLUSION： AI3^-42 is toxic to basal forebrain and hippocampal primary neurons; L-NBP protects against this toxicity and inhibits the induction of caspase-3 and NF- K B expression.
文摘AIM To investigate whether glucagon-like peptide-2(GLP-2) influences the neurally-induced responses in gastric strips from mice, since no data are available. METHODS For functional experiments, gastric fundal strips were mounted in organ baths containing Krebs-Henseleit solution. Mechanical responses were recorded via forcedisplacement transducers, which were coupled to a polygraph for continuous recording of isometric tension. Electrical field stimulation(EFS) was applied via two platinum wire rings through which the preparationwas threaded. The effects of GLP-2(2 and 20 nmol/L) were evaluated on the neurally-induced contractile and relaxant responses elicited by EFS. Neuronal nitric oxide synthase(n NOS) enzyme was evaluated by immunohistochemistry.RESULTS In the functional experiments, electrical field stimulation(EFS, 4-16 Hz) induced tetrodotoxin(TTX)-sensitive contractile responses, which were reduced in amplitude by GLP-2(P < 0.05). In the presence of the nitric oxide(NO) synthesis inhibitor L-NNA, GLP-2 no longer influenced the neurally-evoked contractile responses(P > 0.05). The direct smooth muscle response to methacholine was not influenced by GLP-2(P > 0.05). In the presence of guanethidine and carbachol, the addition of GLP-2 to the bath medium evoked TTX-sensitive relaxant responses that were unaffected by L-NNA(P > 0.05). EFS induced a fast NO-mediated relaxation, whose amplitude was enhanced in the presence of the hormone(P < 0.05). Immunohistochemical experiments showed a significant increase(P < 0.05) in n NOS immunoreactivity in the nerve structures after GLP-2 exposure. CONCLUSION The results demonstrate that in gastric fundal strips, GLP-2 influences the amplitude of neurally-induced responses through the modulation of the nitrergic neurotransmission and increases n NOS expression.
