ABSTRACT
Objective To investigate the effect of granulocyte colony-stimulating factor(G-CSF)and its effect on the cognation in the PDGF hAPPV717I transgenic mice of Alzheimer's disease model.Methods Totally 36 PDGF hAPPV717I transgenic mice were randomly divided into two groups:G-CSF group and control group.The G CSF group was subcutaneously injected with 50 μg · kg-1 · d-1 of G-CSF for 7 days.The control group was injected subcutaneously with an equal volume of PBS in parallel.The animals were tested in Morris water maze on the 7th,14th,and 28th days after the last day of the injection,and the escape latency was recorded.Once the test was completed,the peripheral blood was taken to evaluate the effect of G-CSF to induce hematopoietic stem cells (HSCs) via flow cytometry.Then the mice were killed,their brains were quickly removed and frozen on dry ice.With the immunohistochemical staining and double immunofluorescence staining,the neurogenesis could be observed in the model mice.Results We found that G-CSF significantly shortened the escape latencies in PDGF-hAPPV717I transgenic mice compared to controls on the 7th,14th,and 28th day after G-CSF treatment [7 d:(27.19±4.07) s and (46.07±7.21) s,P＜0.000; 14 d:(26.48±5.29) sand (42.99±11.70) s,P＜0.010; 28 d:(24.97±3.61) s and (45.54±9.55) s,P＜0.002)].At the same time,we found that the percentage of CD34+/CD45+ cells in the peripheral blood was 0.358±0.161,0.223±0.038,0.168±0.049 on the 7th,14th,and 28th day after G-CSF treatment,respectively.Compared with the control group (0.073±0.026,0.067±0.034,0.072± 0.037),the percentage of CD34′ /CD45+ cells in the peripheral blood were increased (P＜0.001).BrdU+ cells were found in dentate gyrus (DG) of hippocampus and the cortex of the G-CSF group,where the BrdU+ /Ncstin- and BrdU-/MAP-2+ cells were also detected positively.Conclusions Subcutaneous administration of G- CSF may improve the cognition in APP transgenic mouse model of AD.G-CSF may mediate the proliferation,differentiation of hcmatopoietic stem cells (HSCs).and may induce the neural stem cells into the brain.
ABSTRACT
AIM: To study cellular and molecular mechanisms of cardiac development associated genes ex- pression and its function during early stage cardiomyogenesis. METHODS: (1 ) Mouse embryonic stem cells (ESC) line D3 culture. (2) Inductive culals of ESC differentiated into cardiac myocytes in vitro.(3) Identification of ESC -derived cardiac myocytes: RNA isolation; synthesis of specific primer and RT - PCR; Label of RT - PCR products with [? - 32P] dATP as probes, purifyed by sephadex G - 50 columns, determined the yield of DNA. RNA dot hy- bridization. RESULTS: 80% of ESC differentiated into cardiomyocytes by improved conditional medium. Cardiomy- ocytes contraCted in a synchronous manner. The results of RT - PCR and RNA blot showed that cardiac genes were expressed abundantly and specifically during the early cardiomyogenesis. CONCLUSIONS: ESC were able to be dif- ferentiate into cardiomyocytes. Different concentrations and components of RA, DMSO and FCS affected ESC car- diomyogenesis in de. The optimal result obtained was from the conditional medium, a mixturce of 2 nmol/L retinoic acid (RA), 0.6% dimethyl sulfoxide (DMSO) and 20% fend calf serum (FCS).