ABSTRACT
Aim To explore the effect of Suanzaoren decoction(SZRD) on mitochondrial dysfunction in AD model of APP/PS1 mice via AMPK/SIRT1/PGC-1α signaling pathway and to reveal the possible mechanism. Methods Thirty APP/PS1 mice were randomly divided into app /PS1 group, low-dose SZRD group(L-SZRD) and high-dose SZRD group(H-SZRD). Ten C57BL/6JNju mice were set as control group(WT). Morris water maze test was used to detect the learning and memory ability of mice. Thioflavin T staining was used to observe senile plaques hippocampus. Immunohistochemistry was performed to detect the expression level of Aβ in hippocampus. Transmission electron microscope was used to observe the mitochondrial morph hology in hippocampus. Kits were employed to detect the contents of ATP and ROS in hippocampus; Western blot was employed to detect the expression levels of AMPK, p-AMPKThrK172, SIRT1, PGC-1α, NRF1, NRF2 and TFAM in hippocampus. Results Compared to the APP/PS1 group, L-SZRD and H-SZRD induced mouse cognitive impairment, reduced the deposition of senile plaques, inhibited the expression of Aβ, improved the damage of mitochondrial structure, increased the content of ATP in the hippocampus, reduced the expression level of ROS in hippocampus and increased the expression of p-AMPK-ThrK172, SIRT1, PGC-1α, NRF1, NRF2, TFAM Conclusions SZRD could improve the cognitive impairment, senile plaque deposition and mitochondrial dysfunction of AD mice, and its mechanism may be involved in the up-regulation of the expression of AMPK/SIRT1/PGC-1α signaling pathway.Reduced the Deposition of Senile Plaques, Inhibited the Expression of Aβ, Improved The Damage of Mitochondric Structure, Increased the Content of At in TH. E hippocampus, Reduced the Expression level of Ros in Hippocampus and Increased The Expression of P-Ampk-Thrk172, SIRT1, SIRT1 PGC-1α, NRF1, NRF2, TFAM. Conclusions SZRD could improve the cognitive impairment, senile plaque deposition and mitochondrial dysfunction of AD mice, and its mechanism may be involved in the up-regulation of the expression of AMPK/SIRT1/PGC-1α signaling pathway.Reduced the Deposition of Senile Plaques, Inhibited the Expression of Aβ, Improved The Damage of Mitochondric Structure, Increased the Content of At in TH. E hippocampus, Reduced the Expression level of Ros in Hippocampus and Increased The Expression of P-Ampk-Thrk172, SIRT1, SIRT1 PGC-1α, NRF1, NRF2, TFAM. Conclusions SZRD could improve the cognitive impairment, senile plaque deposition and mitochondrial dysfunction of AD mice, and its mechanism may be involved in the up-regulation of the expression of AMPK/SIRT1/PGC-1α signaling pathway.Senile plaque deposition and mitochondrial dysfunction of AD mice, and its mechanism may be involved in the up-regulation of the expression of AMPK/SIRT1/PGC-1α signaling pathway.Senile plaque deposition and mitochondrial dysfunction of AD mice, and its mechanism may be involved in the up-regulation of the expression of AMPK/SIRT1/PGC-1α signaling pathway.
ABSTRACT
Objective::To investigate the possible mechanism of Dabuyuan Jian to promote neurogenesis by studying the effect of Dabuyuan Jian on Wnt/β-catenin signaling pathway in hippocampus of amyloid precursor protein/presenilil(APP/PS1) mice. Method::Totally 30 5-month-old APP/PS1 mice and 10 wild mice were divided into control group, model group, donepezil group (6.5×10-4 g·kg-1·d-1) and Dabuyuan Jian group (13.2 g·kg-1·d-1), and given drugs by gavage for 30 days. The control group and the model group were given an equal volume of saline. The learning and memory of mice were evaluated by water maze. The pathological changes of hippocampal neurons were observed by hematoxylin-eosin (HE) staining. The immunohistochemistry (IHC) was used to detect label positive cells of 5-bromodeoxyuridine (Brdu), adrenocortical hormone (Dcx) and neuronal nuclear antigen (NeuN). Real-time fluorescence quantitative polymerase chain reaction (Real-time PCR) and Western bolt were used to detect the mRNA and protein expression levels of β-catenin and glycogen synthase kinase-3β(GSK-3β) in hippocampus of mice. Result::Compared with the control group, the latency and swimming total distance of the model group were significantly increased (P<0.01), while the number of crossing platforms and the target quadrant time were significantly reduced (P<0.01). Compared with the model group, the platform latency and the total swimming distance of the donepezil group and the Dabuyuan Jian group were decreased (P<0.05, P<0.01), while the number of crossing platforms and the target quadrant time were increased (P<0.05). Compared with the control group, the number of neurons in the hippocampal dentate gyrus (DG) area of the model group was decreased, and necrotic neurons were observed. Compared with the model group, the number of neurons in the hippocampal DG area of the mice in the donepezil group and the Dabuyuan Jian group was increased, while the number of necrotic neurons was decreased. Compared with the control group, the number of positive cells labeled with Brdu, Dcx and NeuN in the hippocampal DG area of the model group was significantly decreased (P<0.01). Compared with the model group, the number of positive cells labeled with Brdu, Dcx and NeuN in the hippocampal DG area of the donepezil group and the Dabuyuan Jian group was increased (P<0.05, P<0.01). Compared with the control group, gene and protein expression levels of β-catenin in the hippocampus of the model group were significantly decreased (P<0.01), whereas gene and protein expression levels of GSK-3β were significantly increased (P<0.01). Compared with the model group, gene and protein expression levels of β-catenin in hippocampus of donepezil group and Dabuyuan Jian group were increased (P<0.05, P<0.01), while gene and protein expression levels of GSK-3β were increased (P<0.05, P<0.01). Conclusion::Dabuyuan Jian could promote hippocampal neurogenesis in APP/PS1 double transgenic mice by regulating Wnt/β-catenin signaling pathway.
ABSTRACT
Objective:To observe the effect of Dabuyuan Jian on the synaptic plasticity of hippocampus and the brain derived neurotrophic factor （BDNF）/tyrosine kinase receptor （TrkB）/cyclic adenosine phosphate reactive element binding protein （CREB） signaling pathway in amyloid precursor protein/presenilil （APP/PS1） mice， and to explore its possible mechanism for improving synaptic plasticity. Method:Totally 36 APP/PS1 mice were divided into model group， donepezil group（6.5×10-4 g·kg-1·d-1） and Dabuyuan Jian group （13.2 g·kg-1·d-1）， and another wild mice were set as control group. The mice in control group and model group received an equal volume of saline， and the mice in each group received drugs by gavage for 30 days. The learning ability and memory of mice in each group were detected by Morris water maze. The pathological changes of neurons and synapses in the hippocampus of each group were observed by Nissl staining and Golgi staining. The expression levels of postsynaptic density protein 95 （PSD95） and synaptophysin （SYN） in hippocampus of each group were detected by immunofluorescence （IF）. The protein expression levels of BDNF， TrkB， CREB and phosphorylated CREB （p-CREB） in hippocampus were detected by Western blot. Result:As compared with the control group， the platform latency and total swimming distance of the model group were increased in the model group （P<0.01）， with decreased times of crossing the platform and staying time in the target quadrant （P<0.01）， the intracellular Nissl bodies of neurons in hippocampal CA3 area decreased or disappeared in model group， with decreased number of neurons and dendritic branches and decreased density of dendritic spine in hippocampal CA3 area of the mice （P<0.01）， and the protein expression levels of SYN， PSD95， BDNF， TrkB and p-CREB in hippocampus of mice were also decreased in model group （P<0.05， P<0.01）. As compared with the model group， the platform latency and total swimming distance were decreased in the donepezil group and Dabuyuan Jian group （P<0.05， P<0.01）， with increased times of crossing platform and staying time in target quadrant （P<0.05， P<0.01）， the number of Nissl bodies of neurons in hippocampal CA3 area was increased in the donepezil group and Dabuyuan Jian group， with increased number of neurons and dendritic branches and increased density of dendritic spine in hippocampal CA3 area of the mice， and the protein expression levels of SYN， PSD95， BDNF， TrkB and p-CREB in hippocampus of mice were increased in the donepezil group and Dabuyuan Jian group （P<0.05， P<0.01）. Conclusion:Dabuyuan Jian can improve the synaptic plasticity of APP/PS1 double transgenic mice， and its mechanism may be related to its up-regulation of BDNF/TrkB/CREB signal pathway in mouse hippocampus.
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Objective:To observe the effect of Suanzaoren Tang on hippocampal neuroinflammation in APP/PS1 mice and to explore its possible mechanism of neuroprotection. Method:The mice were randomly divided into blank group, model group, donepezil group(0.92 mg·kg-1), Suanzaoren Tang low and high-dose groups(12.96,25.92 g·kg-1). After 30 days of continuous administration in each group, pathological changes of dentate gyrus (DG) in hippocampus of mice in each group were observed by Nissl staining.The levels of tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β) in serum of each group were detected by enzyme-linked immunosorbent assay (ELISA). Real-time quantitative polymerase chain reaction (Real-time PCR) was used to detect the mRNA expression levels of TNF-α and IL-1β in hippocampus of each group. The expression levels of glial fibrillary acidic protein (GFAP) and ionic calcium binding protein 1 (IBA1) in hippocampus of each group were detected by immunohistochemical staining (ICH) and Western blot. Result:Compared with blank group, the granule cells in DG region were unevenly arranged in model group, with obvious cell loss, and the nissl bodies in some neurons disappeared or condensed, serum TNF-α and IL-1β content significantly increased (Pα and IL-1β mRNA expression quantity significantly increased (PPα and IL-1β in the serum were decreased(PPα and IL-1β mRNA in the hippocampus were decreased(PPPPConclusion:Suanzaoren Tang can improve neuronal loss in APP/PS1 double transgenic mice, and its mechanism may be related to the regulation of hippocampal neuroinflammation in mice.
