The labeling of C57BL/6j derived embryonic stem cells with enhanced green fluorescent protein / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To labele MESPU35, a embryonic stem (ES) cell line derived from C57BL/6j mouse, with enhanced green fluorescent protein (EGFP) for further application.</p><p><b>METHODS</b>The EGFP gene was controlled by the hybrid CA promoter/enhancer (CMV enhancer/chicken beta-actin promoter/beta-actin intron) to construct the vector of the transgene, pCA-EGFP. The vector was transfected into MESPU35 by electroporation.</p><p><b>RESULTS</b>We generated EGFP expressing ES cells demonstrating normal properties. The green fluorescence of EGFP expressing cells was maintained in propagation of the ES cells for more than 30 passages as well as in differentiated cells. Cultured in suspension, the "green" ES cells aggregated, and formed embryoid bodies maintaining the green fluorescence at varying developmental stages. The "green" embryoid bodies could expand and differentiate into various types of cells, exhibiting ubiquitous green fluorescence.</p><p><b>CONCLUSIONS</b>The hybrid CA promoter/enhancer used to control the EGFP expressing ES cells, resulted in more intense and ubiquitous activity. The EGFP transfected cells yield bright green fluorescence, which can be visualized in real time and in situ. In addition, the ES cells, MESPU35, are derived from C57BL/6j mice, which are the most widely used in oncology, physiology and genetics. Compared to 129 substrains, C57BL/6j mice avoid a number of potential problems apparent in the other strains.</p>

Effect of emodin on proliferation and differentiation of 3T3-L1 preadipocyte and FAS activity / 中华医学杂志(英文版)

<p><b>OBJECTIVE</b>To study the effects of emodin on proliferation and differentiation of 3T3-L1 preadipocyte and the possible mechanism.</p><p><b>METHODS</b>Cell proliferation was determined by MTT spectrophotometry, cell differentiation was determined by Oil Red O staining,and fatty acid synthase (FAS) activity was determined by spectrophotometry.</p><p><b>RESULTS</b>Emodin promoted proliferation of 3T3-L1 preadipocyte at low concentration and inhibited the proliferation at high concentration in a dose-related manner. In contrast, it inhibited cell differentiation into adipocyte at low concentration in a dose-related manner. In vitro emodin inhibited the activity of FAS in a dose-related manner.</p><p><b>CONCLUSIONS</b>The effects of emodin on 3T3-L1 cell's proliferation and differentiation are dose dependent. Emodin inhibits the activity of FAS. Our results suggest that emodin should have a potential to serve as a fat-reducing drug.</p>