高脂饮食对去卵巢大鼠骨强度及骨代谢的影响

Effects of high-fat diet on bone strength and metabolic indices of ovariectomized rats

目的观察高脂饮食对去卵巢大鼠骨强度及骨代谢指标的影响。方法雌性SD大鼠随机分为假手术基础饲料组(SHAM组)、假手术高脂饲料组(HFD组)、去卵巢基础饲料组(OVX组)和去卵巢高脂饲料组(OVX-HFD组)。HFD组和OVX-HFD组予30%高脂饲料喂养28周。实验结束时检测血清N端中段骨钙素(N-MID-OT)和抗酒石酸酸性磷酸酶(TRAP)水平,右股骨和腰椎骨密度(BMD)和骨矿含量(BMC),左股骨生物力学性能,左股骨钙、磷和羟脯氨酸含量,测量右股骨远端骨小梁HE染色形态计量学静态参数。结果与SHAM组比较,OVX组血清TRAP显著升高(P=0.000),股骨骨小梁分离度显著增加(P=0.035),股骨BMD和BMC、股骨弹性载荷和最大载荷、股骨羟脯氨酸和钙含量显著降低(P<0.05,P<0.01),HFD组血清N-MID-OT和TRAP显著升高(P=0.007、0.000),股骨和腰椎BMD、BMC显著增加(P<0.05,P<0.01),股骨弹性载荷和最大载荷、钙含量、骨小梁面积百分数、骨小梁厚度显著增加(P<0.05,P<0.01);与OVX组比较,OVX-HFD组血清N-MIDOT和TRAP升高,差异无统计学意义,股骨和腰椎BMD、BMC、股骨弹性载荷和最大载荷、钙含量、骨小梁面积百分数、骨小梁厚度显著增加(P<0.05,P<0.01)。结论 30%高脂饮食对去卵巢大鼠骨可能有保护作用。

Objective To observe the effects of high-fat diet on bone strength and metabolic indices of ovariecto- mized rats. Methods Female SD rats were randomly divided into sham operated group fed normal chow（ SHAM）, sham operated group fed high-fat diet （HFD）, ovariectomized group fed normal chow （OVX） and ovariectomized group treated with high-fat diet （OVX-HFD）. The HFD and OVX-HFD group were fed high-fat diet containing 30% fat for 28 weeks. At the end of the experiment, serum N-MID osteocalcin（N-MID-OT） and tartrate-resistant acid phosphatase（TRAP） were detected; the bone mineral density （BMD） and bone mineral content （BMC） of rats＇ right femurs and lumbar vertebras, the biomechanics of rats＇ left femurs and contents of hydroxyproline, calci- um and phosphorus of rats＇ left femurs were determined. HE staining was used to observe the morphology of rat tra- becula in the distal femoral metaphysis and the static parameters of distal femoral cancellous bone histomorphometry were calculated. Results Compared with SHAM group, serum TRAP level and femoral trabecular bone separation were significantly increased（P =0. 000,0. 035 ）, while femoral BMD,BMC,elastic load, maximum load and con- tents of hydroxyproline and calcium were decreased remarkably（ P 〈 0. 05 ,P 〈 0. 01 ）in OVX group. Compared with those in SHAM group, the serum levels of N-MID-OT and TRAP were elevated significantly （P = 0. 007,0. 000）, and the BMD, BMC of femurs and lumbar vertebras, elastic load, maximum load, femoral calcium contents, the percentage of femoral trabecular bone area and trabecular bone thickness were increased （ P 〈 0. 05, P 〈 0. 01 ） in HFD group. Compared with OVX group, the BMD, BMC of femursand lumbar vertebras, elastic load, maximum load, femoral calcium contents, the percentage of femoral trabecular bone area and trabecular bone thickness were significantly increased（P 〈0. 05 ,P 〈0. 01 ）, while serum levels of N-MID-OT and TRAP were increased without obvious differences in OVX-HFD group. Conclusion The high-fat diet containing 30% fat may have a protective effect on bone of ovariectomized rats.