Effect Of Naoling Decoction On The Expression Of IGF-1 And IGF-1R In Hippocampal CA3 Region Of The Rat With Synthetic Alzheimer Disease

Objects:Alzheimer's disease (Alzheimer's disease, AD) is a progressive central nervous system, progressive degenerative disease, which is mainly manifested as cognitive impairment, decline in activities of daily living and behavioral and psychological symptoms. The Main pathological features are senile plaques (senilep laque, SP), neurofibrillary tangles (neurofibrillaryt angles, NFT) and the selective loss of neurons and synapses.The current prevalence rate of AD increased with age,the prevalence increased by almost 1 times with age by 5 years. Modern medicine in prevention and treatment of this disease has yet to breakthrough. In the study of type 2 diabetes and the relationship between AD, scholars found associated with type 2 diabetes patients, a higher than normal risk of suffering from AD, but the specific cause is not clear? insulin-like growth factor-Ⅰ(insulin-like growth factor-Ⅰ, IGF-Ⅰ) more and more important in the pathogenesis of AD research.Multi-target advantage of Chinese medicine on prevention and treatment of AD provides a broad prospect. This article discusses the Nao-ling Decoction on Alzheimer's disease (AD) model rats behavior, morphology, and hippocampal CA3 hippocampal area of insulin signal transduction pathway associated protein expression of IGF-1 and its receptor influence.This experiment,which is Exposed part of AD pathogenesis and mechanism of Nao-ling Decoctionis To guide the clinical application and development of new drugs to provide theoretical and experimental evidence.Methods:There were 30 pure line SD rats,then they were divided in random into 5 groups:a normal group,a sham operation group,a model group,a wester medicine group,Nao-ling Decoction group(that was traditional chinese medicine group,TCM group).each group is 6 rats.After feed a week,the AD model rats were established by injectionβ-amoyloid 1-42(Aβ1-42) into hippocampus,then feed three weeks, their ability of learning and memory were detected by Y-maze and Morris water maze test after cured for four weeks,.The brain tissue of rats removed to be made frozen sections aim to do for Congo red staining Aβdeposition within the hippocampus.Morphological changes in hippocampus were observed by HE stain. The changes of insulin signal transduction pathway related protein IGF-1 and IGF-1 receptor (IGF-1R) in rat hippocampal CA3 area are shown by immunohistochemical stain.Results:(1).Y-maze test:The highest number of electrical stimulation required is model group.The times of the wester medicine group (P< 0.05) and the TCM group (P< 0.05) to avoid electrical stimulation were significantly less than the required number of model group,with statistical significance. The two treatment groups were not significantly different. (2) Morris water maze test:the model group escape latency of the longest, which TCM group and wester medicine group were significantly different (P<0.05) in hidden platform search experiments. Exploration experiments: we found that the average pass through times in normal group and sham operation group were more than that of other ones. wester medicine group and TCM group the number of times rats crossed more than the model group, which has significant difference (P<0.05). Model group, TCM group and western medicine group have Aβdeposition phenomenon, but TCM and western medicine group than in model group were significantly reduced. Normal group and sham group did not see the deposition of Aβ.TCM group and western medicine group relatively more than the model group in Hippocampal CA3 area in the number of neurons, and the cells were arranged in order. (3) Congo red stain: Although there was deposition ofβ-amoyloid protein both in model group,wester medicine group and TCM group hippocampus sector.there was obviously less in TCM group and wester medicine group than in model group.(4)HE stain: normal group and sham group rat hippocampal CA3 pyramidal cells were arranged in neat with no significant loss of neurons. There is sparse arrangement of pyramidal cells, disorder, significantly reduced the number of pyramidal cells (P<0.05) in Hippocampus in the model group and the number of the model group CA3 neurons decreased. TCM group and western medicine group of hippocampal CA3 neurons than the number of multi-model group, and the cells were arranged in order.(5) Immunohistochemistry: In model group, hippocampal CA3 area IGF-1 and the IGF-1R positive cells at least. the masculine cells about IGF-1 and IGF-1R of Western medicine group and TCM group less than the normal group and sham operation group with statistical significance.Conclusions:(1)The experimental results show that the bilateral hippocampal injection of Aβ1-42 AD model rats, existing pathological changes and learning and memory dysfunction, indicate a successful modeling AD model (2) AD model rats significantly decreased learning and memory, Nao-ling Decoction rats can significantly improve learning and memory. (3) Nao-ling Decoction can reduce the AD hippocampal CA3 neurons lost phenomenon, and to improve the AD hippocampal pyramidal cell morphology, indicating that Nao-ling Decoction has a protective effect in AD brain hippocampal CA3 neurons. (4) Nao-ling Decoction can increases nerve growth factor IGF-I and IGF-IR expression in hippocampal.The study shows part of the mechanism of action.that Nao-ling Decoction may be the treatment of Alzheimer's disease.