Zhang Yan, Leung Ping-Chung, Che Chun-Tao, Chow Hung-Kay, Wu Chun-Fu, Wong Man-Sau
Shenzhen Research Institute of the Hong Kong Polytechnic University, State Ky Laboratory of Chinese Medicine and Molecular Pharmacology, Shenzhen, PRC.
Br J Nutr. 2008 Mar;99(3):494-502. doi: 10.1017/S0007114507801589. Epub 2007 Sep 3.
Fructus Ligustri Lucidi (FLL), a kidney-tonifying Chinese herb, was shown to regulate Ca balance in ovariectomized (OVX) rats in our previous study. This study investigated whether it could improve bone properties in aged normal and OVX rats and increase osteoblastic differentiation in rat osteoblast-like UMR-106 cells. Ten-month-old aged rats underwent sham-operation or ovariectomy, were orally administered with FLL extracts or its vehicle and fed with diets containing different levels of Ca (LCD, 0.1 % Ca; MCD, 0.6 % Ca; HCD, 1.2 % Ca) for 12 weeks. Ovariectomy induced bone loss at multiple-sites of both tibia and femur in all rats being studied. FLL extract increased bone mineral density and bone mineral content at both tibial and femoral diaphysis as well as the lumbar vertebra (LV-2) in rats fed either LCD or MCD. In addition, FLL increased biomechanical strength of the tibial diaphysis in these rats. Combination of FLL and high-Ca diet significantly improved bone mass of cortical and trabecular bone at appendicular bones and LV-2 and decreased bone loss associated with ovarietomy and low-Ca feeding. Treatment of UMR-106 cells with FLL extracts accelerated the formation of calcified matrix and increased extracellular Ca and P depositions in time- and dose-dependent manner. The level of mineralization reached a maximum by 6 d incubation at the dosage of 10 mug FLL extract/ml. Our study indicated that FLL extract could improve bone properties in aged rats possibly via its direct action on osteoblastic cells by enhancement of the mineralization process.
女贞子，一种补肾的中草药，在我们之前的研究中显示可调节去卵巢（OVX）大鼠的钙平衡。本研究调查了其是否能改善老年正常大鼠和去卵巢大鼠的骨骼特性，并增加大鼠成骨样UMR-106细胞的成骨细胞分化。10月龄的老年大鼠接受假手术或去卵巢手术，口服给予女贞子提取物或其溶剂，并喂食含不同钙水平的饲料（低钙饮食，0.1%钙；中钙饮食，0.6%钙；高钙饮食，1.2%钙），持续12周。在所有研究的大鼠中，去卵巢导致胫骨和股骨多处骨质流失。在喂食低钙饮食或中钙饮食的大鼠中，女贞子提取物增加了胫骨和股骨干以及腰椎（LV-2）的骨矿物质密度和骨矿物质含量。此外，女贞子增加了这些大鼠胫骨骨干的生物力学强度。女贞子与高钙饮食联合使用显著改善了四肢骨和LV-2皮质骨和小梁骨的骨量，并减少了与去卵巢和低钙喂养相关的骨质流失。用女贞子提取物处理UMR-106细胞可加速钙化基质的形成，并以时间和剂量依赖性方式增加细胞外钙和磷的沉积。在10μg女贞子提取物/ml的剂量下孵育6天，矿化水平达到最高。我们的研究表明，女贞子提取物可能通过增强矿化过程对成骨细胞的直接作用来改善老年大鼠的骨骼特性。
