Vakakis N, Bower J, Austin L
Department of Biochemistry, Monash University, Clayton, Australia.
Neurochem Int. 1995 Oct-Nov;27(4-5):329-35. doi: 10.1016/0197-0186(95)00014-y.
Leukemia inhibitory factor (LIF) is a pleiotropic cytokine which exerts a variety of effects on many cell types including neuronal cells, and is a potent mitogen for myoblasts. At concentrations of 0.1-0.3 ng/ml, the peptide stimulates a maximal increase in cell number. LIF initiates a prolonged proliferative response lasting up to 13 days, when myoblasts are exposed to it in culture. LIF expression can be detected in vivo during development of limb muscle and in adult regenerating skeletal muscle tissue. Here, we studied the levels of expression of alpha-bungarotoxin-binding sites as a measure of acetylcholine receptors (AChRs), myosin light chain pattern and rate of myotube formation in fused, control and LIF-treated muscle cultures derived from mouse hind-limb muscles. We found that both the level of expression of AChRs and myosin light chain pattern, are normal, following exposure of the cells to LIF. There was no difference in the rate of myotube formation between LIF-stimulated and control myoblasts over a 10-fold concentration range (0.3-3.0 ng/ml) as determined by nuclei counts. Taken together, these results suggest that LIF, in combination with other cytokines, may act in vivo to stimulate rapid growth, without significant differentiation, during the early phases of myogenesis.
白血病抑制因子（LIF）是一种多效性细胞因子，对包括神经元细胞在内的多种细胞类型具有多种作用，并且是成肌细胞的强效促有丝分裂原。在浓度为0.1 - 0.3纳克/毫升时，该肽刺激细胞数量最大程度增加。当成肌细胞在培养中暴露于LIF时，LIF引发持续长达13天的延长增殖反应。在肢体肌肉发育期间的体内以及成年再生骨骼肌组织中均可检测到LIF表达。在此，我们研究了源自小鼠后肢肌肉的融合、对照和LIF处理的肌肉培养物中作为乙酰胆碱受体（AChRs）指标的α-银环蛇毒素结合位点的表达水平、肌球蛋白轻链模式以及肌管形成速率。我们发现，细胞暴露于LIF后，AChRs的表达水平和肌球蛋白轻链模式均正常。通过细胞核计数确定，在10倍浓度范围（0.3 - 3.0纳克/毫升）内，LIF刺激的成肌细胞与对照成肌细胞之间的肌管形成速率没有差异。综上所述，这些结果表明，LIF与其他细胞因子结合，可能在体内发挥作用，在肌发生的早期阶段刺激快速生长，而无明显分化。
