1.PTK2B affects the levels of Aβ in blood and brain and behavioral functions via targeting LRP-1 transporter in Aβ-induced cognitive dysfunction mice.
Kai-Min HAO ; Zhen LIU ; Hao-Yu WANG ; Kun LI ; Wen-Xiu QI
Acta Physiologica Sinica 2021;73(5):845-854
The aim of the present study was to explore the correlation between ptk2b/PTK2B (protein tyrosine kinase 2 beta, a ptk2b-encoded protein) and the level of low density lipoprotein receptor-related protein-1 (LRP-1), as well as to uncover the relationship between the changes in beta amyloid protein (Aβ) levels in blood and brain and the expression of ptk2b in Aβ-induced cognitive dysfunction mice. A total of 64 3-month-old C57BL/6J mice were divided randomly into the experimental group and control group. All mice underwent the intracerebroventricular (i.c.v.) intubation. Mice in the experimental group received the i.c.v. infusion of oligomeric Aβ
Alzheimer Disease
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Amyloid beta-Peptides/metabolism*
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Animals
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Brain
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Cognitive Dysfunction/chemically induced*
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Disease Models, Animal
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Focal Adhesion Kinase 2
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Hippocampus/metabolism*
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Mice
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Mice, Inbred C57BL
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Peptide Fragments
3.Dexmedetomidine-mediated Wnt Pathway Inhibits Sevoflurane-induced Cognitive Impairment in Neonatal Rats.
Yue YANG ; Lei YANG ; Yu WU ; Jun YUAN
Acta Academiae Medicinae Sinicae 2021;43(2):235-246
Objective To explore the effect of dexmedetomidine(Dex)on sevoflurane-induced cognitive impairment in neonatal rats through Wnt signaling pathway. Methods Sixty 7-day-old SD rats were assigned into five groups:control group(without any intervention),Dex group(intraperitoneal injection of 25 μg/kg Dex),sevoflurane group(3% sevoflurane treatment for 4 hours),sevoflurane+Dex group(inhalation of 3% sevoflurane after injection of 25 μg/kg Dex for 4 hours),and sevoflurane+Dex+Wnt inhibitor group(Wnt inhibitor XAV393 and 25 μg/kg Dex were injected and 3% sevoflurane was inhaled for 4 hours).Three weeks later,Morris water maze was used to detect the cognitive function;TdT-mediated dUTP nick end labeling(TUNEL)staining was performed to detect the apoptosis of hippocampal neurons;neuronal nuclei (NeuN) staining was conducted to detect the survival of hippocampal neurons;Western blot was carried out to detect the expression of apoptosis-related proteins.The expression of the factors involved in Wnt/GSK-3β/β-catenin signaling pathway was detected by fluorescence quantitative polymerase chain reaction,and Western blot. Results Compared with the control group,there was no significant difference in the escape latency of Dex group(t=0.304,P=0.768);the escape latency in sevoflurane group(t=5.823,P=0.002),sevoflurane+Dex group(t=3.188,P=0.010),and sevoflurane+Dex+Wnt inhibitor group(t=5.784,P=0.002)was significantly prolonged.Compared with that in the sevoflurane group,the escape latency in sevoflurane+Dex group(t=3.646,P=0.005)was significantly shortened.Compared with that in sevoflurane+Dex group,the escape latency in sevoflurane+Dex+Wnt inhibitor group(t=3.296,P=0.008)was prolonged.Compared with that in the control group,the times of crossing platform in sevoflurane group(t=5.179, P=0.004),sevoflurane+Dex group(t=2.309,P=0.043),and sevoflurane+Dex+Wnt inhibitor group(t=3.871, P=0.003)decreased.Compared with that in sevoflurane group,the times of crossing platform in sevoflurane+Dex group(t=3.296,P=0.008)significantly increased.Compared with that in sevoflurane+Dex group,the times of crossing platform in sevoflurane+Dex+Wnt inhibitor group(t=2.361, P=0.041)reduced.Compared with the control group,there was no significant difference in the number of apoptotic cells in Dex group(t=1.920,P=0.127),and the number of apoptotic cells in sevoflurane group,sevoflurane+Dex group,and sevoflurane+Dex+Wnt inhibitor group increased by 16%(t=13.436,P=0.002),5%(t=7.752, P=0.001),and 11.5%(t=12.612,P=0.002),respectively.Compared with that in the sevoflurane group,the number of apoptotic cells in sevoflurane+Dex group and sevoflurane+Dex+Wnt inhibitor group decreased by 11%(t=8.521,P=0.002)and 5.5%(t=3.123,P=0.036),respectively.Compared with that in the sevoflurane+Dex group,the number of apoptotic cells in sevoflurane+Dex+Wnt inhibitor group increased by 6.5%(t=6.250,P=0.003).Compared with that in the control group,the number of positive cells in 0.15 mm
Animals
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Animals, Newborn
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Cognitive Dysfunction/chemically induced*
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Dexmedetomidine/pharmacology*
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Glycogen Synthase Kinase 3 beta
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Rats
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Rats, Sprague-Dawley
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Sevoflurane/toxicity*
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Wnt Signaling Pathway
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beta Catenin/metabolism*
4.Effect of rutaecarpine on Alzheimer's disease-like cognitive impairments induced by high glucose in rats.
Jian Guo CHEN ; Ya Geng WU ; Xiang LI
Chinese Journal of Applied Physiology 2019;35(2):178-182
OBJECTIVE:
To investigate the effects of rutaecarpine on high glucose-induced Alzheimer's disease-like pathological and cognitive dysfunction and its mechanism in rats.
METHODS:
Adult male SD rats were randomly divided into three groups (n=20): control group, high glucose group and rutaecarpine group. Rats in the control group were fed with conventional feed and tap water. The rats in the high glucose group were fed with conventional feed and 20% sucrose water. The rutaecarpine group was fed with fodder contain 0.01% rutaecarpine and 20% sucrose water. Morris water maze test was used to detect learning and memory and cognitive function of three groups rats after 24 weeks of feeding. Western blot analysis was used to detect tau protein at Thr205 and Ser214 sites in each group. Phosphorylation levels of GSK-3β in serine 9 site (S9-GSK-3β) and PP2A at cycline 307 site (Y307-PP2AC) were also detected. Immunohistochemistry further confirmed tau protein at Thr205 site in each group both in hippocampus and cortex.
RESULTS:
Compared with the control group, Morris water maze results showed that the latency of finding the hidden platform of the rats in high glucose group was increased significantly and the number of crossing platforms and the target quadrant residence time were significantly decreased (all P<0.05). Immunohistochemistry showed that the phosphorylation level of tau protein at Thr205 site was significantly increased in the high glucose group compared with the control group, and the phosphorylation level of tau protein at Thr205 site in the rutaecarpine group was higher than that in the high glucose group. Western blot analysis showed that the phosphorylation level of tau protein in the high glucose group was significantly increased at Thr205 and Ser214 site compared with the control group, but the phosphorylation level of pS9-GSK-3β was significantly decreased (all P <0.05). Compared with the high glucose group, the latency of finding the hidden platform of the rats in rutaecarpine group was significantly decreased, and the number of crossing platforms and the target quadrant residence time were significantly increased (both P<0.05). Compared with the high glucose group, the phosphorylation levels of tau protein at Thr205 and Ser214 sites showed a significant decrease, but the phosphorylation level of pS9-GSK-3β was significantly increased (all P<0.05).
CONCLUSION
Rutaecarpine can alleviate AD-like cognitive dysfunction induced by high glucose, possibly by enhancing pS9-GSK-3β phosphorylation, down-regulating GSK-3β activity, and thus reducing hyperphosphorylation of tau-associated sites.
Alzheimer Disease
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chemically induced
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drug therapy
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Animals
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Cognitive Dysfunction
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chemically induced
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drug therapy
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Glucose
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Glycogen Synthase Kinase 3 beta
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chemistry
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Indole Alkaloids
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pharmacology
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Male
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Maze Learning
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Phosphorylation
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Quinazolines
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pharmacology
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Random Allocation
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Rats
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Rats, Sprague-Dawley
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tau Proteins
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chemistry