Ⅰ型神经纤维瘤病基因型小鼠的破骨细胞功能研究

目的 观察Ⅰ型神经纤维瘤病基因型小鼠的破骨细胞功能变化,探讨Ⅰ型神经纤维瘤病引起骨质疏松的发病机制.方法 选取神经纤维瘤病基因杂合型(Nfl+/-)和野生型(Nfl+/+)小鼠为研究对象,取胫骨干骺端行抗酒石酸酸性磷酸酶(TRAP)染色,比较两组小鼠骨内破骨细胞含量.体外实验取两种基因型小鼠的骨髓单核细胞,观察在巨噬细胞集落刺激因子(M-CSF)和细胞核因子KB受体活化因子配基(RANKL)诱导下的破骨细胞分化能力,测定两组破骨细胞形成、分化、贴附、迁移和骨吸收功能.结果 Nfl+/一小鼠骨内成熟破骨细胞数量比Nn+/+增多,细胞体积明显增大(TRAP阳性区面积占总面积的百分比分别为Nfl+/+,(0.8800±0.0014)%;Nfl+/-,(2.3300±0.0013)%,P<0.01),差异有统计学意义;体外培养的Nn+/-破骨细胞形成增多,(每1×105骨髓单核细胞形成的破骨细胞数分别为Nfl+/+,41.75±13.14:N仃+/-,61.17±18.17,P<0.01)差异有统计学意义;体外诱导培养的破骨细胞的黏附、迁移、骨吸收功能强(黏附细胞数量Nn+/+,53.00±11.08;Nil+/-,108.00±11.67,JP<0.01;迁移细胞数量Nn+/+,88.33±12.40;Nn+/-,239.83±67.77,P<0.01骨吸收面积百分比Nfl+/+.18.37%±0.0367;Nfl+/-,(40.4400±0.1052)%,P<0.01).两者差异有统计学意义.结论 破骨细胞增多,功能增强是Ⅰ型神经纤维瘤病引起骨质疏松的发病机制之一.

Osteoclast hyperfunction in neurofibromatosis type 1 murine model

Objective To investigate cellular functions of osteoclasts derived from Nfl hcterozygote ( Nil +/- ) and wild type ( Nil +/+ ) mice,and analyze the mechanism of the osteopomrosis in neurofibromatosis type Ⅰ. Methods Stain histological sections of tibias from Nil +/- and Nfl +/+ mice with H＆E or for tartrate-resistant acid phosphatase (TRAP) activity, and measure the osteoclasts contained in metaphysis;Cuhure the low density bone marrow cells from Nfl +/- and Nfl +/+ mice with macrophage colony-stimulating factor (M-CSF) and receptor activator of NF-κB ligand (RANKL) ,examine the frequency of nsteoclast progenitor, and evaluate multiple functions, including migration, adhesion, and bone absorption. Results Nfl +/- mice contain numerons enlarged hypernucleated osteoclasts in vivo than Nil-/- mice. (TRAP+ area/total area Nil +/+,0.88% +0.0014;Nfl +/- ,2.33% s0. 0013 ,P <0.01 ) ,The number of Nfl +/- osteoclast formated from 1 x 10s low dencity bone marrow cells are higher than that of Nfl + / + with significant difference. ( Nil + / + ,41.75±13.14 ; Nfl + / - ,61.17 ±18.17,P <0.01 ). The mutiple functions of osteoclasts derived from Nil heterozygote are higher than those of wild type with significant difference(adhesion Nil +/+ ,53±11.08;Nil +/- ,108±11.67,P <0.01 ;migration Nil +/+ ,88.33±12.40;Nfl +/- ,239.83±67.77, P < 0.01 ;pit formation Nil +/ +,18.37%±0.0367;Nfl +/-40.44,%±0.1052,P<0.01). Conclusion The hyper osteoclast fuc-tions in Nil +/- mice may be responsible for the pathogenesis of NF1 osteopmais.