Intracerebroventricular transplantation of human amniotic epithelial cells ameliorates spatial memory deficit in the doubly transgenic mice coexpressing APPswe and PS1ΔE9-deleted genes / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human amniotic epithelial cells (HAECs), which have characteristics of both embryonic and pluripotent stem cells, are therefore a candidate in cell therapy without creating legal or ethical problems. In the present study, we aimed to investigate the effects of intracerebroventricular transplantation of HAECs on doubly transgenic mice of Alzheimer's disease (AD) coexpressing presenilin-1 (PS1) and mutant Sweden amyloid precursor protein (APPswe) genes.</p><p><b>METHODS</b>The offspring mice genotypes were detected using PCR identification of APPswe and PS1 gene. The doubly transgenic (TG) mice (n = 20) and wild-type (WT) mice (n = 20) were randomly divided into two groups respectively: the transplantation group treated with HAECs and the control group with phosphate buffered saline. Six radial arm water maze test was used to assess the spatial memory in the TG and WT mice. Amyloid plaques and neurofibrillary tangles were analyzed using congo red and acid-silver methenamine staining respectively. Immunofluorescence cytochemistry was used to track the survival of HAECs. Immunohistochemistry was used to determine the expression of octamer-binding protein 4 (Oct-4) and Nanog in the HAECs. High performance liquid chromatography was used to measure acetylcholine in hippocampus. The density of cholinergic neurons in basal forebrain and nerve fibers in hippocampus was measured using acetylcholinesterase staining.</p><p><b>RESULTS</b>Amyloid deposition occurred in hippocampus and frontal cortex in the double TG mice aged 8 months, but not in WT mice. The results also showed that transplanted HAECs can survive for at least 8 weeks and migrate to the third ventricle without immune rejection. The graft HAECs can also express the specific marker Oct-4 and Nanog of stem cell. Compared with the control group, transplantation of HAECs can not only significantly improve the spatial memory of the TG mice, but also increase acetylcholine concentration and the number of hippocampal cholinergic neurites.</p><p><b>CONCLUSIONS</b>These results demonstrate that intracerebroventricular transplantation of HAECs can improve the spatial memory of the double TG mice. The higher content of acetylcholine in hippocampus released by more survived cholinergic neurites is one of the causes of this improvement.</p>

An analysis of vascular factors of Alzheimer′s disease and an experimental intervention of tanshinone Ⅱ A on mouse models of AD / 中华神经医学杂志

Objective To evaluate the relationship between Alzheimer′s disease(AD)and its partial vascular risk factors,and investigate the effect of tanshinone ⅡA(Tan ⅡA)on experimental models of AD combined with chronic cerebral ischemia and its potential mechanism.Methods Eight hundred and forty-nine patients with dementia(549 having diagnosis of AD and 300 without AD),admitted to our hospital from 1975 to 2009,were collected in our study; univariate analysis was performed on the relation between AD and vascular risk factors.Besides that,Tg+ mice were employed in our study and randomly divided into 5 groups,namely,sham-operated group,vehicle group,low Tan ⅡA treatment group,medium Tan ⅡA treatment group and high Tan ⅡA treatment group; or these mice were randomly divided into sham-operated group,vehicle group,Tan ⅡA treatment group(treated with 10 mg/kg daily).Mouse models of AD and chronic cerebral ischemia were established,and Tan ⅡA treatment was given to the Tan ⅡA treatment group.The relationship between AD and vascular factors was assessed by means of analyzing the clinicopathological data of AD cohort.The changes of learning and memory abilities in the mouse models were detected by Morris water maze test.Enzyme-linked immuno sorbent assay(ELISA)was employed to detect the level of VEGF; the protein expressions of betaA4-amyloid precursor protein (APP),VEGF and VEGFR-1 were determined by Western blotting,and the mRNA expressions of APP,VEGF and VEGFR-1 were observed by quantitative RT PCR.The effect of Tan ⅡA on canaliculization of human umbilical vein endothelial cells(HUVECs)was also investigated fiom cellular level.Results AD was significantly positively correlated with such vascular risk factors as hypertension,diabetes mellitus,coronary disease,cerebrovascular disease and hyperlipemia(P＜0.05),while no correlation was noted between AD and pneumonia.The mice of the medium Tan ⅡA treatment group and high Tan ⅡA treatment group had obviously shortened times of searching the platform and swimming distance,prolonged latency of avoiding darkness,decreased frequency of wrong behaviors,and decreased level of VEGF as compared with the vehicle group(P＜0.05).The life span in mice of the Tan ⅡA treatment group (treated with 10 mg/kg daily)was prolonged for approximately 24 d as compared with that in the vehicle group; the expressions of APP and VEGF were down-regulated and that of VEGFR-1 in mice of the Tan ⅡA treatment group(treated with 10 mg/kg daily)was up-regulated as compared with those in the vehicle group(P＜0.05).The canaliculization of HUVECs was enhanced after incubation with Tan ⅡA for 48 h,followed by increase of VEGFR-1 expression.Conclusion AD is significantly correlated with its vascular factors.Tan ⅡA could improve the learning and memory abilities of dementia mouse through up-regnlation of VEGFR-1 expression and promotion of vascular integrity,indicating the crucial role of vascular factors in treatment of AD.

Therapeutic effect of human amniotic epithelial cell transplantation into the lateral ventricle of hemiparkinsonian rats / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Human amniotic epithelial cells (HAECs) are able to secrete biologically active neurotrophins such as brain-derived neurotrophic factor and neurotrophin-3, both of which exhibit trophic activities on dopamine neurons. Previous study showed that when human amniotic epithelial cells were transplanted into the striatum of 6-hydroxydopamine (6-OHDA)-induced Parkinson disease rats, the cells could survive and exert functional effects. The purpose of this study was to investigate the survival and the differentiation of human amniotic epithelial cells after being transplanted into the lateral ventricle of Parkinson's disease (PD) rats, and to investigate the effects of grafts on healing PD in models.</p><p><b>METHODS</b>The Parkinson's model was made with stereotactic microinjection of 6-hydroxydopamine (6-OHDA) into the striatum of a rat. The PD models were divided into two groups: the HAECs group and the normal saline (NS) group. Some untreated rats were taken as the control. The rotational asymmetry induced by apomorphine of the HAECs group and the NS group were measured post cell transplantation. The expression of nestin and vimentin in grafts were determined by immunohistology. Ten weeks after transplantation the density of tyrosine hydroxylase positive cells in the substantia nigra of the HAECs group, NS group and the untreated group was determined. The differentiation of grafts was determined by TH immunohistology. High performance liquid chromatography (HPLC) was used to determine monoamine neurotransmitter levels in the striatum.</p><p><b>RESULTS</b>The rotational asymmetry induced by apomorphine of the HAECs group was ameliorated significantly compared to the NS group two weeks after transplantation (P < 0.01). The grafts expressed nestin and vimentin five weeks after transplantation. TH immunohistochemistry indicated that the TH positive cells in the substantia nigra of the HAECs group increased significantly compared to the NS group (P < 0.01). Tyrosine hydroxylase (TH) positive cells in the substantia nigra of the HAEC group and the NS group were decreased compared to the untreated group (P < 0.01). Dopamine and DOPAC levels in the striatum of the HAECs group increased significantly compared to the NS group (P < 0.05). Homovanillic acid (HVA) levels in the striatum of the HAECs group increased significantly compared to the NS group (P < 0.01). In addition dopamine, DOPAC, and HVA levels in the striatum and dopamine levels in the cerebrospinal fluid of the HAECs group and the NS group were decreased compared to the untreated group (P < 0.05).</p><p><b>CONCLUSIONS</b>Human amniotic epithelial cells could be used to ameliorate the rotational asymmetry induced by apomorphine of the PD models. This could have been due to the increased content of dopamine and its metabolic products, DOPAC and HVA, in the striatum in the PD models.</p>