ADA2013：脂肪肝对骨微结构有不利影响

在成人和青少年，已经有研究证明非酒精性脂肪肝（NAFLD）对骨矿密度（BMD）有不利影响。然而，大部分的证据来自于临床横断面研究，不能确保这种不利影响。为此，来自同济大学医学院的曲伸教授及其团队进行了一项研究，该研究发现小鼠高脂饮食诱导的脂肪肝对骨微结构有不利影响。

该研究中，实验开始时，选择46只8-10周、平均体重15-20g的C57雄性小鼠，并分为2组：饲养12周的标准饲料（对照组；21只）或高脂饮食（2%胆固醇，7%猪油，8.3%蛋黄，16.7%蔗糖和66%基础饲料，HFD组；25例）。处死后，收集股骨、胫骨和肝脏标本。在高分辨率扫描模式（体素大小和层面厚度为20mm）中，使用显微CT系统（mCT-80；Scanco医疗公司）扫描骨标本。

在HFD组，20只小鼠通过肝活检证实脂肪肝。比较对照组和NAFLD组之间的组织骨密度（TMD）、总骨体积分数（BV/TV）、骨小梁厚度（Tb.Th）、骨小梁数码（Tb.N）、骨小梁间距（Tb.Sp）、连接密度（Conn.D）和结构模型指数（SMI）。

该研究结果表明，与对照组相比，脂肪肝组有更低水平的TMD（59.741±23.038 vs 112.196±54.940；P=0.028）、BV/TV（0.017±0.003 vs 0.068±0.044；P=0.007）、SMI（3.918±0.568 vs 2.860±0.579；P=0.006）和Tb.Th（0.050±0.006 vs 0.063±0.006；P＜0.001）。在胫骨，脂肪肝小鼠同时有更低水平的TMD（25.078±19.822 vs 85.462±34.011；P=0.021）、BV/TV（0.023±0.012 vs 0.068±0.017；P＜0.001）、Conn.D（0.359±1.688 vs 8.522±6.458；P=0.023）、SMI (3.428±.412 vs 2.529±.454；P=0.002) 、Tb.Th (0.048±0.007 vs 0.061±0.007；P=0.004)、Tb.Sp (0.636±0.158 vs 0.441±0.145；P=0.022).和Tb.Th（0.050±0.006 vs 0.063±0.006；P＜0.001）。

该研究结果证实，小鼠高脂饮食诱导的脂肪肝对骨微结构有不利影响。然而，需要进一步的研究探讨其中的机制。

It has been proved that non-alcoholic fatty liver disease (NAFLD) had detrimental effect on bone mineral density (BMD) in both adults and adolescents. However most of the evidence was from clinical cross section study which cannot ensure the adverse effect.

Thus we performed an animal experiment to certify this phenomenon.46 C57 male mice 8-10 weeks old average body weight 15-20g at the beginning of the experiment were enrolled and divided into two groups feeding for 12 weeks either standard chow (control; N = 21) or high-fat diet (2% cholesterol 7% lard 8.3% yolk 16.7% sucrose and 66% base forage HFD; N = 25). Femur Tibia and liver samples were collected after sacrifice. The bone samples were scanned using a micro-CT system (mCT-80; Scanco Medical AG) in a high-resolution scanning mode (a voxel size and slice thickness of 20 mm).

 In HFD group 20 mice were proved with fatty liver by liver biopsy. Tissue mineral density (TMD) total bone volume fraction (BV/TV) trabecular thickness (Tb.Th) trabecular number (Tb.N) trabecular separation (Tb.Sp) connectivity density (Conn.D) and structure model index (SMI) were compared between control and NAFLD group.

Compared to control group fatty liver group had a lower level of TMD (59.741±23.038 vs. 112.196±54.940 P=0.028) BV/TV (0.017±0.003 vs. 0.068±0.044 P=0.007) SMI (3.918±0.568 vs. 2.860±0.579 P=0.006) and Tb.Th (0.050±0.006 vs. 0.063±0.006 P<0.001). For tibia fatty liver also had a lower level in TMD (25.078±19.822 vs. 85.462±34.011 P=0.021) BV/TV (0.023±0.012 vs. 0.068±0.017 P<0.001) Conn.D (0.359±1.688 vs. 8.522±6.458 P=0.023) SMI (3.428±.412 vs. 2.529±.454 P=0.002) Tb.Th (0.048±0.007 vs. 0.061±0.007 P=0.004) and Tb.Sp (0.636±0.158 vs. 0.441±0.145 P=0.022).

 Our results convinced the adverse effect on bone microstructure of high fat diet induced fatty liver mice. However further study was needed to investigate the mechanism.

编辑： 葛根    来源：丁香园