骨碎补总黄酮对去卵巢大鼠下颌骨结构、血清E2及OPG/RANKL的影响
Effects of drynaria total flavonoids on mandible structure, serum E2 and OPG/RANKL balance in ovariectomized rats

摘要：目的 探讨骨碎补总黄酮对去卵巢大鼠下颌骨结构及血清雌二醇(E2)水平、血清骨保护素/细胞核因子κB受体活化因子配基(OPG/RANKL)平衡的影响。方法 将40只3月龄雌性SD大鼠随机分为假手术组(Sham)、去卵巢模型组(OVX)、骨碎补总黄酮高剂量组(GB-H)、骨碎补总黄酮低剂量组(GB-L)和戊酸雌二醇组(EV)。采用摘除大鼠双侧卵巢的方法构建下颌骨骨质疏松模型，给药12周后处死大鼠。截取大鼠下颌磨牙段进行组织切片观察和形态计量学测量，放射免疫法检测血清E2水平，ELISA法检测血清OPG、RANKL水平。结果 与Sham组相比，OVX组大鼠下颌骨呈疏松样改变，E2水平显著降低(P<0.001)，OPG和OPG/RANKL比值显著降低(P<0.001，P<0.001)。与OVX组相比，EV组大鼠下颌骨结构获得良好修复，血清E？？2回升(P<0.001)，OPG/RANKL比值显著增加(P<0.001)。与OVX组相比，GB-H、GB-L组下颌骨骨小梁面积百分率均增加(P<0.001，P=0.029)及血清OPG/RANKL比值(P<0.001，P=0.007)均增高，GB-H组下颌骨骨小梁厚度及血清OPG水平增加(P=0.019，P<0.001)，骨小梁间距减小(P=0.001)，但均对血清E2水平无影响(P=0.432，P=0.459)。 结论 骨碎补总黄酮能抑制去卵巢大鼠的下颌骨结构破坏，从而减缓下颌骨骨量丢失，但不能提高血清E2水平，其途径可能是通过调节OPG/RANKL平衡实现的。
ABSTRACT: Objective To explore the effects of drynaria total flavonoids on serum estrogen (E2) level, OPG/RANKL balance and bone microarchitecture of mandible in a rat model of bone loss induced by ovariectomy. Methods We randomly divided 40 three-month-old female Sprague-Dawley rats into 5 groups (n=8 per group): sham-operation group (Sham), ovariectomized group (OVX), low-dose drynaria total flavonoids group (GB-L), high-dose drynaria total flavonoids group (GB-H) and estradiol valerate group (EV). The mandibular osteoporosis model was established by removing the rats’ ovaries. After 12 weeks the rats were killed, and the serum estrogen levels were measured. OPG and RANKL were detected using ELISA method. Therapeutic effect of drynaria total flavonoids was observed by pathomorphology and histomorphometry of the mandibular molar sections. Results Compared with those in the sham group, the mandible of rats in OVX group was loosely changed, the level of E2 decreased significantly (P<0.001), and OPG/RANKL decreased significantly (P<0.001). Compared with OVX group, the mandible microstructure of rats in EV group got a good repair, while the serum E2 level and OPG/RANKL increased significantly (both P<0.001). Compared with OVX group, the percentage of trabecular bone (%Tb.Ar) and OPG/RANKL increased in all the GB groups (P<0.001, P=0.029), (P<0.001, P=0.007), while GB-H group also had increased thickness of trabecular bone (Tb.Th) and serum OPG levels (P=0.019, P<0.001), reduced trabecular spacing (Tb.Sp)(P=0.001), but no effect on serum E2 level (P=0.432, P=0.459). Conclusion Drynaria total flavonoids can inhibit the destruction of the mandibular trabecular structure, thus slowing down the mandibular resorption process. However, they cannot improve E2 concentration. The mechanism is realized by adjusting the balance of OPG/RANKL