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>

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>