Induction-dependent neural marker expression and electrophysiological characteristics of bone marrow mesenchymal stem cells that naturally express high levels of nestin

• 来源期刊: 科学通报(英文版)
• 学科: 医学
• 年，卷（期）: 2011,（7）
• 页码范围: 640-646
• 页数: 7页
• 分类号: R741
• 语种: 中文

摘要

Under certain experimental conditions, bone marrow mesenchymal stem cells (MSCs) express neuronal phenotypes and neuronal markers, which suggests that they could be used to treat various neurological diseases. In the present study, MSCs were isolated from adult rat bone marrow, cultivated, and evaluated for neurotrophin expression profiles, as well as the potential to differentiate into functional neuronal-like cells in vitro. MSCs from passage 5 were pre-induced with DMEM/F12 medium containing 10% fetal bovine serum (FBS) and 10 ng/mL bFGF (fibroblast growth factor-2). Subsequently, a chemical inductor containing Di-methyl Sulphoxide (DMSO), Butylated Hydroxyanisole (BHA) and forskolin were used to induce neural expression of MSCs. Expression patterns of nestin, NF-200, and GFAP at time points before and after induction were detected by immunofluorescence. Nerve Growth Factor (NGF), brain-derived neurotrophic factor (BDNF) expressions in MSCs were evaluated by RT-PCR. The whole-cell patch clamp technique was utilized to elucidate the electrical behavior of MSC before and after 24-h differentia-tion induction. Immunofluorescence analysis revealed that MSCs expressed nestin (57.1% ± 6.9%), but not NF-200 or GFAP. Following neural induction, the cells exhibited a neuronal-like appearance. Nestin and NF-200 expression was positive in the neuronal-like cells, but GFAP expression was negative. After 6-, 12-and 24-h induction, the ratio of nestin-positive cells was 96.5% ± 1.9%, 88.1% ± 5.4%, and 33.5% ± 5.4%. NF-200 positive cells were 90.1% ± 2.9%, 97.5% ± 1.3%, and 98.1% ± 1.6%, respectively. However, prior to induction, MSCs already expressed NGF and BDNF. With a stimulus impulse of 40 mV, the den-sity of the transient outward K current was (9.95 ± 4.85) pA/pF (n = 9) and (328.50 ± 30.62) pA/pF (n = 9) before and after induc-tion, and the density of transient calcium ion currents was (–0.059 ± 0.027) pA/pF (n = 7) and (–6.66 ± 0.50) pA/pF (n = 7), re-spectively. Transient outward potassium currents and calcium ions currents gradually increased following induction. In addition, MSCs isolated from bone marrow exhibited characteristics of neuronal progenitor cells and expressed neurotrophins. These cells exhibited the capacity to differentiate into functional neuronal-like cells in vitro. These results suggested that MSCs express high levels of nestin and could be utilized for therapeutic strategies to treat nervous system diseases.