模拟微重力诱导成骨细胞微丝变化对一氧化氮/一氧化氮合酶系统的影响  

Disruption of the microfilament cytoskeleton induced by simulated microgravity affects NO/ NOS system of osteoblasts

作　　者：王脉桃[1] 黄震[2] 杨锐[1] 苏嘉霖[1] 麦燕兴[1] 周焕成[3] 邓伟民[4] 

机构地区：[1]南方医科大学珠江医院内分泌科,广东广州51028 [2]南方医科大学珠江医院外科学教研室,广东广州510282 [3]南方医科大学珠江医院肝胆外科,广东广州510282 [4]广州军区总医院华侨科,广东广州510010

出　　处：《南方医科大学学报》2010年第7期1658-1662,共5页Journal of Southern Medical University

摘　　要：目的研究模拟微重力诱导细胞微丝结构变化对一氧化氮/一氧化氮合酶(NO/NOS)系统的调控作用,探讨失重导致骨质疏松的机制。方法本研究以小鼠成骨样细胞株(MC3T3-E1)作对象,以回转器模拟微重力效应。实验将细胞分为4组:模拟微重力组、5μg/ml细胞松弛素B组、模拟微重力+0.5μg/ml细胞松弛素B组及对照组正常重力组。培养48h后,利用FITC-Phallacidin进行免疫荧光染色,在激光共聚焦显微镜下观察各组细胞微丝的变化;同时使用NOS分型试剂盒测定各组细胞NOS的酶活性,通过硝酸还原酶法检测各组细胞培养液中NO浓度。结果除了正常重力组外,其余各组呈现不同程度的细胞微丝结构解聚,张力纤维减少,且排列紊乱,以模拟微重力+0.5μg/ml细胞松弛素B组改变最为明显。与正常重力组相比,其余各组诱导型一氧化氮合酶(iNOS)的酶活性和NO的浓度均提高,内皮型一氧化氮合酶(eNOS)的酶活性则有所下降,均以模拟微重力+0.5μg/ml细胞松弛素B组变化最为明显。结论我们推测微重力诱导细胞骨架微丝解聚,可以调控NO/NOS系统而影响信号传导。Objective To study the effect of microfilament cytoskeleton changes induced by simulated microgravity on the NO/NOS system of osteoblasts, and explore the mechanism of weightlessness leading to osteoporosis. Methods Mouse osteoblast-like cell line MC3T3-E1 were divided into simulated microgravity （by rotating clinostat） group, 0.5 μg/ml cytochalasins B group, simulated microgravity ＋ cytochalasins B group, and normal gravity group. After cell culture for 48 h with corresponding treatments, immunofluorescence staining of the cells by FITC-phallacidin was performed to observe the changes of microfilament under laser confocal microscope. NOS activity of the cells was tested with NOS detection kit, and the NO concentration in the cell supernatant was measured with nitrate reductase method. Results Depolymerization of the microfilament cytoskeleton with irregular arrangement and reduced tension fibers occurred in the cells except for those in the normal gravity group, which was especially obvious in the microgravity＋ cytochalasins B group. Compared with the normal gravity group, the cells in the other groups showed increased iNOS activity and NO concentration but decreased eNOS activity, especially obvious in simulated microgravity＋ cytochalasins B group. Conclusion Disruption of the microfilament cytoskeleton induced by simulated microgravity can regulate the NO/NOS system to influence the signal transduction of the osteoblasts.

关 键 词：微重力 成骨细胞 细胞骨架 一氧化氮 一氧化氮合酶 

分 类 号：R85[医药卫生—航空、航天与航海医学]